Actual source code: mpiaij.c

  1: #include <../src/mat/impls/aij/mpi/mpiaij.h>
  2: #include <petsc/private/vecimpl.h>
  3: #include <petsc/private/sfimpl.h>
  4: #include <petsc/private/isimpl.h>
  5: #include <petscblaslapack.h>
  6: #include <petscsf.h>
  7: #include <petsc/private/hashmapi.h>

  9: /* defines MatSetValues_MPI_Hash(), MatAssemblyBegin_MPI_Hash(), and MatAssemblyEnd_MPI_Hash() */
 10: #define TYPE AIJ
 11: #define TYPE_AIJ
 12: #include "../src/mat/impls/aij/mpi/mpihashmat.h"
 13: #undef TYPE
 14: #undef TYPE_AIJ

 16: static PetscErrorCode MatReset_MPIAIJ(Mat mat)
 17: {
 18:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

 20:   PetscFunctionBegin;
 21:   PetscCall(PetscLogObjectState((PetscObject)mat, "Rows=%" PetscInt_FMT ", Cols=%" PetscInt_FMT, mat->rmap->N, mat->cmap->N));
 22:   PetscCall(MatStashDestroy_Private(&mat->stash));
 23:   PetscCall(VecDestroy(&aij->diag));
 24:   PetscCall(MatDestroy(&aij->A));
 25:   PetscCall(MatDestroy(&aij->B));
 26: #if PetscDefined(USE_CTABLE)
 27:   PetscCall(PetscHMapIDestroy(&aij->colmap));
 28: #else
 29:   PetscCall(PetscFree(aij->colmap));
 30: #endif
 31:   PetscCall(PetscFree(aij->garray));
 32:   PetscCall(VecDestroy(&aij->lvec));
 33:   PetscCall(VecScatterDestroy(&aij->Mvctx));
 34:   PetscCall(PetscFree2(aij->rowvalues, aij->rowindices));
 35:   PetscCall(PetscFree(aij->ld));
 36:   PetscFunctionReturn(PETSC_SUCCESS);
 37: }

 39: static PetscErrorCode MatResetHash_MPIAIJ(Mat mat)
 40: {
 41:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
 42:   /* Save the nonzero states of the component matrices because those are what are used to determine
 43:     the nonzero state of mat */
 44:   PetscObjectState Astate = aij->A->nonzerostate, Bstate = aij->B->nonzerostate;

 46:   PetscFunctionBegin;
 47:   PetscCall(MatReset_MPIAIJ(mat));
 48:   PetscCall(MatSetUp_MPI_Hash(mat));
 49:   aij->A->nonzerostate = ++Astate, aij->B->nonzerostate = ++Bstate;
 50:   PetscFunctionReturn(PETSC_SUCCESS);
 51: }

 53: PetscErrorCode MatDestroy_MPIAIJ(Mat mat)
 54: {
 55:   PetscFunctionBegin;
 56:   PetscCall(MatReset_MPIAIJ(mat));

 58:   PetscCall(PetscFree(mat->data));

 60:   /* may be created by MatCreateMPIAIJSumSeqAIJSymbolic */
 61:   PetscCall(PetscObjectCompose((PetscObject)mat, "MatMergeSeqsToMPI", NULL));

 63:   PetscCall(PetscObjectChangeTypeName((PetscObject)mat, NULL));
 64:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatStoreValues_C", NULL));
 65:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatRetrieveValues_C", NULL));
 66:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatGetMultPetscSF_C", NULL));
 67:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatIsTranspose_C", NULL));
 68:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetPreallocation_C", NULL));
 69:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatResetPreallocation_C", NULL));
 70:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatResetHash_C", NULL));
 71:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetPreallocationCSR_C", NULL));
 72:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatDiagonalScaleLocal_C", NULL));
 73:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpibaij_C", NULL));
 74:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpisbaij_C", NULL));
 75: #if PetscDefined(HAVE_CUDA)
 76:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijcusparse_C", NULL));
 77: #endif
 78: #if PetscDefined(HAVE_HIP)
 79:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijhipsparse_C", NULL));
 80: #endif
 81: #if PetscDefined(HAVE_KOKKOS_KERNELS)
 82:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijkokkos_C", NULL));
 83: #endif
 84:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpidense_C", NULL));
 85: #if PetscDefined(HAVE_ELEMENTAL)
 86:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_elemental_C", NULL));
 87: #endif
 88: #if PetscDefined(HAVE_SCALAPACK) && (PetscDefined(USE_REAL_SINGLE) || PetscDefined(USE_REAL_DOUBLE))
 89:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_scalapack_C", NULL));
 90: #endif
 91: #if PetscDefined(HAVE_HYPRE)
 92:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_hypre_C", NULL));
 93:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_transpose_mpiaij_mpiaij_C", NULL));
 94: #endif
 95:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_is_C", NULL));
 96:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_is_mpiaij_C", NULL));
 97:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_mpiaij_mpiaij_C", NULL));
 98:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetUseScalableIncreaseOverlap_C", NULL));
 99:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijperm_C", NULL));
100:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijsell_C", NULL));
101: #if PetscDefined(HAVE_MKL_SPARSE)
102:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijmkl_C", NULL));
103: #endif
104:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijcrl_C", NULL));
105:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_is_C", NULL));
106:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpisell_C", NULL));
107:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatSetPreallocationCOO_C", NULL));
108:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatSetValuesCOO_C", NULL));
109:   PetscFunctionReturn(PETSC_SUCCESS);
110: }

112: static PetscErrorCode MatGetRowIJ_MPIAIJ(Mat A, PetscInt oshift, PetscBool symmetric, PetscBool inodecompressed, PetscInt *m, const PetscInt *ia[], const PetscInt *ja[], PetscBool *done)
113: {
114:   Mat B;

116:   PetscFunctionBegin;
117:   PetscCall(MatMPIAIJGetLocalMat(A, MAT_INITIAL_MATRIX, &B));
118:   PetscCall(PetscObjectCompose((PetscObject)A, "MatGetRowIJ_MPIAIJ", (PetscObject)B));
119:   PetscCall(MatGetRowIJ(B, oshift, symmetric, inodecompressed, m, ia, ja, done));
120:   PetscCall(MatDestroy(&B));
121:   PetscFunctionReturn(PETSC_SUCCESS);
122: }

124: static PetscErrorCode MatRestoreRowIJ_MPIAIJ(Mat A, PetscInt oshift, PetscBool symmetric, PetscBool inodecompressed, PetscInt *m, const PetscInt *ia[], const PetscInt *ja[], PetscBool *done)
125: {
126:   Mat B;

128:   PetscFunctionBegin;
129:   PetscCall(PetscObjectQuery((PetscObject)A, "MatGetRowIJ_MPIAIJ", (PetscObject *)&B));
130:   PetscCall(MatRestoreRowIJ(B, oshift, symmetric, inodecompressed, m, ia, ja, done));
131:   PetscCall(PetscObjectCompose((PetscObject)A, "MatGetRowIJ_MPIAIJ", NULL));
132:   PetscFunctionReturn(PETSC_SUCCESS);
133: }

135: /*MC
136:    MATAIJ - MATAIJ = "aij" - A matrix type to be used for sparse matrices.

138:    This matrix type is identical to` MATSEQAIJ` when constructed with a single process communicator,
139:    and `MATMPIAIJ` otherwise.  As a result, for single process communicators,
140:   `MatSeqAIJSetPreallocation()` is supported, and similarly `MatMPIAIJSetPreallocation()` is supported
141:   for communicators controlling multiple processes.  It is recommended that you call both of
142:   the above preallocation routines for simplicity.

144:    Options Database Key:
145: . -mat_type aij - sets the matrix type to `MATAIJ` during a call to `MatSetFromOptions()`

147:   Developer Note:
148:   Level: beginner

150:     Subclasses include `MATAIJCUSPARSE`, `MATAIJPERM`, `MATAIJSELL`, `MATAIJMKL`, `MATAIJCRL`, `MATAIJKOKKOS`,and also automatically switches over to use inodes when
151:    enough exist.

153: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateAIJ()`, `MatCreateSeqAIJ()`, `MATBAIJ`
154: M*/

156: /*MC
157:    MATAIJCRL - MATAIJCRL = "aijcrl" - A matrix type to be used for sparse matrices.

159:    This matrix type is identical to `MATSEQAIJCRL` when constructed with a single process communicator,
160:    and `MATMPIAIJCRL` otherwise.  As a result, for single process communicators,
161:    `MatSeqAIJSetPreallocation()` is supported, and similarly `MatMPIAIJSetPreallocation()` is supported
162:   for communicators controlling multiple processes.  It is recommended that you call both of
163:   the above preallocation routines for simplicity.

165:    Options Database Key:
166: . -mat_type aijcrl - sets the matrix type to `MATMPIAIJCRL` during a call to `MatSetFromOptions()`

168:   Level: beginner

170: .seealso: [](ch_matrices), `Mat`, `MatCreateMPIAIJCRL`, `MATSEQAIJCRL`, `MATMPIAIJCRL`, `MATSEQAIJ`, `MATMPIAIJ`, `MATAIJ`
171: M*/

173: static PetscErrorCode MatBindToCPU_MPIAIJ(Mat A, PetscBool flg)
174: {
175:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

177:   PetscFunctionBegin;
178: #if PetscDefined(HAVE_CUDA) || PetscDefined(HAVE_HIP) || PetscDefined(HAVE_VIENNACL)
179:   A->boundtocpu = flg;
180: #endif
181:   if (a->A) PetscCall(MatBindToCPU(a->A, flg));
182:   if (a->B) PetscCall(MatBindToCPU(a->B, flg));

184:   /* In addition to binding the diagonal and off-diagonal matrices, bind the local vectors used for matrix-vector products.
185:    * This maybe seems a little odd for a MatBindToCPU() call to do, but it makes no sense for the binding of these vectors
186:    * to differ from the parent matrix. */
187:   if (a->lvec) PetscCall(VecBindToCPU(a->lvec, flg));
188:   if (a->diag) PetscCall(VecBindToCPU(a->diag, flg));
189:   PetscFunctionReturn(PETSC_SUCCESS);
190: }

192: static PetscErrorCode MatSetBlockSizes_MPIAIJ(Mat M, PetscInt rbs, PetscInt cbs)
193: {
194:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)M->data;

196:   PetscFunctionBegin;
197:   if (mat->A) {
198:     PetscCall(MatSetBlockSizes(mat->A, rbs, cbs));
199:     PetscCall(MatSetBlockSizes(mat->B, rbs, 1));
200:   }
201:   PetscFunctionReturn(PETSC_SUCCESS);
202: }

204: static PetscErrorCode MatFindNonzeroRows_MPIAIJ(Mat M, IS *keptrows)
205: {
206:   Mat_MPIAIJ      *mat = (Mat_MPIAIJ *)M->data;
207:   Mat_SeqAIJ      *a   = (Mat_SeqAIJ *)mat->A->data;
208:   Mat_SeqAIJ      *b   = (Mat_SeqAIJ *)mat->B->data;
209:   const PetscInt  *ia, *ib;
210:   const MatScalar *aa, *bb, *aav, *bav;
211:   PetscInt         na, nb, i, j, *rows, cnt = 0, n0rows;
212:   PetscInt         m = M->rmap->n, rstart = M->rmap->rstart;

214:   PetscFunctionBegin;
215:   *keptrows = NULL;

217:   ia = a->i;
218:   ib = b->i;
219:   PetscCall(MatSeqAIJGetArrayRead(mat->A, &aav));
220:   PetscCall(MatSeqAIJGetArrayRead(mat->B, &bav));
221:   for (i = 0; i < m; i++) {
222:     na = ia[i + 1] - ia[i];
223:     nb = ib[i + 1] - ib[i];
224:     if (!na && !nb) {
225:       cnt++;
226:       goto ok1;
227:     }
228:     aa = aav + ia[i];
229:     for (j = 0; j < na; j++) {
230:       if (aa[j] != 0.0) goto ok1;
231:     }
232:     bb = PetscSafePointerPlusOffset(bav, ib[i]);
233:     for (j = 0; j < nb; j++) {
234:       if (bb[j] != 0.0) goto ok1;
235:     }
236:     cnt++;
237:   ok1:;
238:   }
239:   PetscCallMPI(MPIU_Allreduce(&cnt, &n0rows, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)M)));
240:   if (!n0rows) {
241:     PetscCall(MatSeqAIJRestoreArrayRead(mat->A, &aav));
242:     PetscCall(MatSeqAIJRestoreArrayRead(mat->B, &bav));
243:     PetscFunctionReturn(PETSC_SUCCESS);
244:   }
245:   PetscCall(PetscMalloc1(M->rmap->n - cnt, &rows));
246:   cnt = 0;
247:   for (i = 0; i < m; i++) {
248:     na = ia[i + 1] - ia[i];
249:     nb = ib[i + 1] - ib[i];
250:     if (!na && !nb) continue;
251:     aa = aav + ia[i];
252:     for (j = 0; j < na; j++) {
253:       if (aa[j] != 0.0) {
254:         rows[cnt++] = rstart + i;
255:         goto ok2;
256:       }
257:     }
258:     bb = PetscSafePointerPlusOffset(bav, ib[i]);
259:     for (j = 0; j < nb; j++) {
260:       if (bb[j] != 0.0) {
261:         rows[cnt++] = rstart + i;
262:         goto ok2;
263:       }
264:     }
265:   ok2:;
266:   }
267:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)M), cnt, rows, PETSC_OWN_POINTER, keptrows));
268:   PetscCall(MatSeqAIJRestoreArrayRead(mat->A, &aav));
269:   PetscCall(MatSeqAIJRestoreArrayRead(mat->B, &bav));
270:   PetscFunctionReturn(PETSC_SUCCESS);
271: }

273: static PetscErrorCode MatDiagonalSet_MPIAIJ(Mat Y, Vec D, InsertMode is)
274: {
275:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)Y->data;
276:   PetscBool   cong;

278:   PetscFunctionBegin;
279:   PetscCall(MatHasCongruentLayouts(Y, &cong));
280:   if (Y->assembled && cong) PetscCall(MatDiagonalSet(aij->A, D, is));
281:   else PetscCall(MatDiagonalSet_Default(Y, D, is));
282:   PetscFunctionReturn(PETSC_SUCCESS);
283: }

285: static PetscErrorCode MatFindZeroDiagonals_MPIAIJ(Mat M, IS *zrows)
286: {
287:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)M->data;
288:   PetscInt    i, rstart, nrows, *rows;

290:   PetscFunctionBegin;
291:   *zrows = NULL;
292:   PetscCall(MatFindZeroDiagonals_SeqAIJ_Private(aij->A, &nrows, &rows));
293:   PetscCall(MatGetOwnershipRange(M, &rstart, NULL));
294:   for (i = 0; i < nrows; i++) rows[i] += rstart;
295:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)M), nrows, rows, PETSC_OWN_POINTER, zrows));
296:   PetscFunctionReturn(PETSC_SUCCESS);
297: }

299: static PetscErrorCode MatGetColumnReductions_MPIAIJ(Mat A, PetscInt type, PetscReal *reductions)
300: {
301:   Mat_MPIAIJ        *aij = (Mat_MPIAIJ *)A->data;
302:   PetscInt           i, m, n, *garray = aij->garray;
303:   Mat_SeqAIJ        *a_aij = (Mat_SeqAIJ *)aij->A->data;
304:   Mat_SeqAIJ        *b_aij = (Mat_SeqAIJ *)aij->B->data;
305:   const PetscScalar *dummy;

307:   PetscFunctionBegin;
308:   PetscCall(MatGetSize(A, &m, &n));
309:   PetscCall(PetscArrayzero(reductions, n));
310:   PetscCall(MatSeqAIJGetArrayRead(aij->A, &dummy));
311:   PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &dummy));
312:   PetscCall(MatSeqAIJGetArrayRead(aij->B, &dummy));
313:   PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &dummy));
314:   if (type == NORM_2) {
315:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) reductions[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i] * a_aij->a[i]);
316:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) reductions[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i] * b_aij->a[i]);
317:   } else if (type == NORM_1) {
318:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) reductions[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i]);
319:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) reductions[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i]);
320:   } else if (type == NORM_INFINITY) {
321:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) reductions[A->cmap->rstart + a_aij->j[i]] = PetscMax(PetscAbsScalar(a_aij->a[i]), reductions[A->cmap->rstart + a_aij->j[i]]);
322:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) reductions[garray[b_aij->j[i]]] = PetscMax(PetscAbsScalar(b_aij->a[i]), reductions[garray[b_aij->j[i]]]);
323:   } else if (type == REDUCTION_SUM_REALPART || type == REDUCTION_MEAN_REALPART) {
324:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) reductions[A->cmap->rstart + a_aij->j[i]] += PetscRealPart(a_aij->a[i]);
325:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) reductions[garray[b_aij->j[i]]] += PetscRealPart(b_aij->a[i]);
326:   } else {
327:     PetscCheck(type == REDUCTION_SUM_IMAGINARYPART || type == REDUCTION_MEAN_IMAGINARYPART, PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONG, "Unknown reduction type");
328:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) reductions[A->cmap->rstart + a_aij->j[i]] += PetscImaginaryPart(a_aij->a[i]);
329:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) reductions[garray[b_aij->j[i]]] += PetscImaginaryPart(b_aij->a[i]);
330:   }
331:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, reductions, n, MPIU_REAL, type == NORM_INFINITY ? MPIU_MAX : MPIU_SUM, PetscObjectComm((PetscObject)A)));
332:   if (type == NORM_2) {
333:     for (i = 0; i < n; i++) reductions[i] = PetscSqrtReal(reductions[i]);
334:   } else if (type == REDUCTION_MEAN_REALPART || type == REDUCTION_MEAN_IMAGINARYPART) {
335:     for (i = 0; i < n; i++) reductions[i] /= m;
336:   }
337:   PetscFunctionReturn(PETSC_SUCCESS);
338: }

340: static PetscErrorCode MatFindOffBlockDiagonalEntries_MPIAIJ(Mat A, IS *is)
341: {
342:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)A->data;
343:   IS              sis, gis;
344:   const PetscInt *isis, *igis;
345:   PetscInt        n, *iis, nsis, ngis, rstart, i;

347:   PetscFunctionBegin;
348:   PetscCall(MatFindOffBlockDiagonalEntries(a->A, &sis));
349:   PetscCall(MatFindNonzeroRows(a->B, &gis));
350:   PetscCall(ISGetSize(gis, &ngis));
351:   PetscCall(ISGetSize(sis, &nsis));
352:   PetscCall(ISGetIndices(sis, &isis));
353:   PetscCall(ISGetIndices(gis, &igis));

355:   PetscCall(PetscMalloc1(ngis + nsis, &iis));
356:   PetscCall(PetscArraycpy(iis, igis, ngis));
357:   PetscCall(PetscArraycpy(iis + ngis, isis, nsis));
358:   n = ngis + nsis;
359:   PetscCall(PetscSortRemoveDupsInt(&n, iis));
360:   PetscCall(MatGetOwnershipRange(A, &rstart, NULL));
361:   for (i = 0; i < n; i++) iis[i] += rstart;
362:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)A), n, iis, PETSC_OWN_POINTER, is));

364:   PetscCall(ISRestoreIndices(sis, &isis));
365:   PetscCall(ISRestoreIndices(gis, &igis));
366:   PetscCall(ISDestroy(&sis));
367:   PetscCall(ISDestroy(&gis));
368:   PetscFunctionReturn(PETSC_SUCCESS);
369: }

371: /*
372:   Local utility routine that creates a mapping from the global column
373: number to the local number in the off-diagonal part of the local
374: storage of the matrix.  When PETSC_USE_CTABLE is used this is scalable at
375: a slightly higher hash table cost; without it it is not scalable (each processor
376: has an order N integer array but is fast to access.
377: */
378: PetscErrorCode MatCreateColmap_MPIAIJ_Private(Mat mat)
379: {
380:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
381:   PetscInt    n   = aij->B->cmap->n, i;

383:   PetscFunctionBegin;
384:   PetscCheck(!n || aij->garray, PETSC_COMM_SELF, PETSC_ERR_PLIB, "MPIAIJ Matrix was assembled but is missing garray");
385: #if PetscDefined(USE_CTABLE)
386:   PetscCall(PetscHMapICreateWithSize(n, &aij->colmap));
387:   for (i = 0; i < n; i++) PetscCall(PetscHMapISet(aij->colmap, aij->garray[i] + 1, i + 1));
388: #else
389:   PetscCall(PetscCalloc1(mat->cmap->N + 1, &aij->colmap));
390:   for (i = 0; i < n; i++) aij->colmap[aij->garray[i]] = i + 1;
391: #endif
392:   PetscFunctionReturn(PETSC_SUCCESS);
393: }

395: #define MatSetValues_SeqAIJ_A_Private(row, col, value, addv, orow, ocol) \
396:   do { \
397:     if (col <= lastcol1) low1 = 0; \
398:     else high1 = nrow1; \
399:     lastcol1 = col; \
400:     while (high1 - low1 > 5) { \
401:       t = (low1 + high1) / 2; \
402:       if (rp1[t] > col) high1 = t; \
403:       else low1 = t; \
404:     } \
405:     for (_i = low1; _i < high1; _i++) { \
406:       if (rp1[_i] > col) break; \
407:       if (rp1[_i] == col) { \
408:         if (addv == ADD_VALUES) { \
409:           ap1[_i] += value; \
410:           /* Not sure LogFlops will slow down the code or not */ \
411:           (void)PetscLogFlops(1.0); \
412:         } else ap1[_i] = value; \
413:         goto a_noinsert; \
414:       } \
415:     } \
416:     if (value == 0.0 && ignorezeroentries && row != col) { \
417:       low1  = 0; \
418:       high1 = nrow1; \
419:       goto a_noinsert; \
420:     } \
421:     if (nonew == 1) { \
422:       low1  = 0; \
423:       high1 = nrow1; \
424:       goto a_noinsert; \
425:     } \
426:     PetscCheck(nonew != -1, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Inserting a new nonzero at global row/column (%" PetscInt_FMT ", %" PetscInt_FMT ") into matrix", orow, ocol); \
427:     MatSeqXAIJReallocateAIJ(A, am, 1, nrow1, row, col, rmax1, aa, ai, aj, rp1, ap1, aimax, nonew, MatScalar); \
428:     N = nrow1++ - 1; \
429:     a->nz++; \
430:     high1++; \
431:     /* shift up all the later entries in this row */ \
432:     PetscCall(PetscArraymove(rp1 + _i + 1, rp1 + _i, N - _i + 1)); \
433:     PetscCall(PetscArraymove(ap1 + _i + 1, ap1 + _i, N - _i + 1)); \
434:     rp1[_i] = col; \
435:     ap1[_i] = value; \
436:   a_noinsert:; \
437:     ailen[row] = nrow1; \
438:   } while (0)

440: #define MatSetValues_SeqAIJ_B_Private(row, col, value, addv, orow, ocol) \
441:   do { \
442:     if (col <= lastcol2) low2 = 0; \
443:     else high2 = nrow2; \
444:     lastcol2 = col; \
445:     while (high2 - low2 > 5) { \
446:       t = (low2 + high2) / 2; \
447:       if (rp2[t] > col) high2 = t; \
448:       else low2 = t; \
449:     } \
450:     for (_i = low2; _i < high2; _i++) { \
451:       if (rp2[_i] > col) break; \
452:       if (rp2[_i] == col) { \
453:         if (addv == ADD_VALUES) { \
454:           ap2[_i] += value; \
455:           (void)PetscLogFlops(1.0); \
456:         } else ap2[_i] = value; \
457:         goto b_noinsert; \
458:       } \
459:     } \
460:     if (value == 0.0 && ignorezeroentries) { \
461:       low2  = 0; \
462:       high2 = nrow2; \
463:       goto b_noinsert; \
464:     } \
465:     if (nonew == 1) { \
466:       low2  = 0; \
467:       high2 = nrow2; \
468:       goto b_noinsert; \
469:     } \
470:     PetscCheck(nonew != -1, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Inserting a new nonzero at global row/column (%" PetscInt_FMT ", %" PetscInt_FMT ") into matrix", orow, ocol); \
471:     MatSeqXAIJReallocateAIJ(B, bm, 1, nrow2, row, col, rmax2, ba, bi, bj, rp2, ap2, bimax, nonew, MatScalar); \
472:     N = nrow2++ - 1; \
473:     b->nz++; \
474:     high2++; \
475:     /* shift up all the later entries in this row */ \
476:     PetscCall(PetscArraymove(rp2 + _i + 1, rp2 + _i, N - _i + 1)); \
477:     PetscCall(PetscArraymove(ap2 + _i + 1, ap2 + _i, N - _i + 1)); \
478:     rp2[_i] = col; \
479:     ap2[_i] = value; \
480:   b_noinsert:; \
481:     bilen[row] = nrow2; \
482:   } while (0)

484: static PetscErrorCode MatSetValuesRow_MPIAIJ(Mat A, PetscInt row, const PetscScalar v[])
485: {
486:   Mat_MPIAIJ  *mat = (Mat_MPIAIJ *)A->data;
487:   Mat_SeqAIJ  *a = (Mat_SeqAIJ *)mat->A->data, *b = (Mat_SeqAIJ *)mat->B->data;
488:   PetscInt     l, *garray                         = mat->garray, diag;
489:   PetscScalar *aa, *ba;

491:   PetscFunctionBegin;
492:   /* code only works for square matrices A */

494:   /* find size of row to the left of the diagonal part */
495:   PetscCall(MatGetOwnershipRange(A, &diag, NULL));
496:   row = row - diag;
497:   for (l = 0; l < b->i[row + 1] - b->i[row]; l++) {
498:     if (garray[b->j[b->i[row] + l]] > diag) break;
499:   }
500:   if (l) {
501:     PetscCall(MatSeqAIJGetArray(mat->B, &ba));
502:     PetscCall(PetscArraycpy(ba + b->i[row], v, l));
503:     PetscCall(MatSeqAIJRestoreArray(mat->B, &ba));
504:   }

506:   /* diagonal part */
507:   if (a->i[row + 1] - a->i[row]) {
508:     PetscCall(MatSeqAIJGetArray(mat->A, &aa));
509:     PetscCall(PetscArraycpy(aa + a->i[row], v + l, a->i[row + 1] - a->i[row]));
510:     PetscCall(MatSeqAIJRestoreArray(mat->A, &aa));
511:   }

513:   /* right of diagonal part */
514:   if (b->i[row + 1] - b->i[row] - l) {
515:     PetscCall(MatSeqAIJGetArray(mat->B, &ba));
516:     PetscCall(PetscArraycpy(ba + b->i[row] + l, v + l + a->i[row + 1] - a->i[row], b->i[row + 1] - b->i[row] - l));
517:     PetscCall(MatSeqAIJRestoreArray(mat->B, &ba));
518:   }
519:   PetscFunctionReturn(PETSC_SUCCESS);
520: }

522: PetscErrorCode MatSetValues_MPIAIJ(Mat mat, PetscInt m, const PetscInt im[], PetscInt n, const PetscInt in[], const PetscScalar v[], InsertMode addv)
523: {
524:   Mat_MPIAIJ *aij   = (Mat_MPIAIJ *)mat->data;
525:   PetscScalar value = 0.0;
526:   PetscInt    i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
527:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
528:   PetscBool   roworiented = aij->roworiented;

530:   /* Some Variables required in the macro */
531:   Mat         A     = aij->A;
532:   Mat_SeqAIJ *a     = (Mat_SeqAIJ *)A->data;
533:   PetscInt   *aimax = a->imax, *ai = a->i, *ailen = a->ilen, *aj = a->j;
534:   PetscBool   ignorezeroentries = a->ignorezeroentries;
535:   Mat         B                 = aij->B;
536:   Mat_SeqAIJ *b                 = (Mat_SeqAIJ *)B->data;
537:   PetscInt   *bimax = b->imax, *bi = b->i, *bilen = b->ilen, *bj = b->j, bm = aij->B->rmap->n, am = aij->A->rmap->n;
538:   MatScalar  *aa, *ba;
539:   PetscInt   *rp1, *rp2, ii, nrow1, nrow2, _i, rmax1, rmax2, N, low1, high1, low2, high2, t, lastcol1, lastcol2;
540:   PetscInt    nonew;
541:   MatScalar  *ap1, *ap2;

543:   PetscFunctionBegin;
544:   PetscCall(MatSeqAIJGetArray(A, &aa));
545:   PetscCall(MatSeqAIJGetArray(B, &ba));
546:   for (i = 0; i < m; i++) {
547:     if (im[i] < 0) continue;
548:     PetscCheck(im[i] < mat->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Row too large: row %" PetscInt_FMT " max %" PetscInt_FMT, im[i], mat->rmap->N - 1);
549:     if (im[i] >= rstart && im[i] < rend) {
550:       row      = im[i] - rstart;
551:       lastcol1 = -1;
552:       rp1      = PetscSafePointerPlusOffset(aj, ai[row]);
553:       ap1      = PetscSafePointerPlusOffset(aa, ai[row]);
554:       rmax1    = aimax[row];
555:       nrow1    = ailen[row];
556:       low1     = 0;
557:       high1    = nrow1;
558:       lastcol2 = -1;
559:       rp2      = PetscSafePointerPlusOffset(bj, bi[row]);
560:       ap2      = PetscSafePointerPlusOffset(ba, bi[row]);
561:       rmax2    = bimax[row];
562:       nrow2    = bilen[row];
563:       low2     = 0;
564:       high2    = nrow2;

566:       for (j = 0; j < n; j++) {
567:         if (v) value = roworiented ? v[i * n + j] : v[i + j * m];
568:         if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES) && im[i] != in[j]) continue;
569:         if (in[j] >= cstart && in[j] < cend) {
570:           col   = in[j] - cstart;
571:           nonew = a->nonew;
572:           MatSetValues_SeqAIJ_A_Private(row, col, value, addv, im[i], in[j]);
573:         } else if (in[j] < 0) {
574:           continue;
575:         } else {
576:           PetscCheck(in[j] < mat->cmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column too large: col %" PetscInt_FMT " max %" PetscInt_FMT, in[j], mat->cmap->N - 1);
577:           if (mat->was_assembled) {
578:             if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
579: #if PetscDefined(USE_CTABLE)
580:             PetscCall(PetscHMapIGetWithDefault(aij->colmap, in[j] + 1, 0, &col)); /* map global col ids to local ones */
581:             col--;
582: #else
583:             col = aij->colmap[in[j]] - 1;
584: #endif
585:             if (col < 0 && !((Mat_SeqAIJ *)aij->B->data)->nonew) { /* col < 0 means in[j] is a new col for B */
586:               PetscCall(MatDisAssemble_MPIAIJ(mat, PETSC_FALSE));  /* Change aij->B from reduced/local format to expanded/global format */
587:               col = in[j];
588:               /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
589:               B     = aij->B;
590:               b     = (Mat_SeqAIJ *)B->data;
591:               bimax = b->imax;
592:               bi    = b->i;
593:               bilen = b->ilen;
594:               bj    = b->j;
595:               ba    = b->a;
596:               rp2   = PetscSafePointerPlusOffset(bj, bi[row]);
597:               ap2   = PetscSafePointerPlusOffset(ba, bi[row]);
598:               rmax2 = bimax[row];
599:               nrow2 = bilen[row];
600:               low2  = 0;
601:               high2 = nrow2;
602:               bm    = aij->B->rmap->n;
603:               ba    = b->a;
604:             } else if (col < 0 && !(ignorezeroentries && value == 0.0)) {
605:               PetscCheck(1 == ((Mat_SeqAIJ *)aij->B->data)->nonew, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Inserting a new nonzero at global row/column (%" PetscInt_FMT ", %" PetscInt_FMT ") into matrix", im[i], in[j]);
606:               PetscCall(PetscInfo(mat, "Skipping of insertion of new nonzero location in off-diagonal portion of matrix %g(%" PetscInt_FMT ",%" PetscInt_FMT ")\n", (double)PetscRealPart(value), im[i], in[j]));
607:             }
608:           } else col = in[j];
609:           nonew = b->nonew;
610:           MatSetValues_SeqAIJ_B_Private(row, col, value, addv, im[i], in[j]);
611:         }
612:       }
613:     } else {
614:       PetscCheck(!mat->nooffprocentries, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Setting off process row %" PetscInt_FMT " even though MatSetOption(,MAT_NO_OFF_PROC_ENTRIES,PETSC_TRUE) was set", im[i]);
615:       if (!aij->donotstash) {
616:         mat->assembled = PETSC_FALSE;
617:         if (roworiented) {
618:           PetscCall(MatStashValuesRow_Private(&mat->stash, im[i], n, in, PetscSafePointerPlusOffset(v, i * n), (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
619:         } else {
620:           PetscCall(MatStashValuesCol_Private(&mat->stash, im[i], n, in, PetscSafePointerPlusOffset(v, i), m, (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
621:         }
622:       }
623:     }
624:   }
625:   PetscCall(MatSeqAIJRestoreArray(A, &aa)); /* aa, bb might have been free'd due to reallocation above. But we don't access them here */
626:   PetscCall(MatSeqAIJRestoreArray(B, &ba));
627:   PetscFunctionReturn(PETSC_SUCCESS);
628: }

630: /*
631:     This function sets the j and ilen arrays (of the diagonal and off-diagonal part) of an MPIAIJ-matrix.
632:     The values in mat_i have to be sorted and the values in mat_j have to be sorted for each row (CSR-like).
633:     No off-processor parts off the matrix are allowed here and mat->was_assembled has to be PETSC_FALSE.
634: */
635: PetscErrorCode MatSetValues_MPIAIJ_CopyFromCSRFormat_Symbolic(Mat mat, const PetscInt mat_j[], const PetscInt mat_i[])
636: {
637:   Mat_MPIAIJ *aij    = (Mat_MPIAIJ *)mat->data;
638:   Mat         A      = aij->A; /* diagonal part of the matrix */
639:   Mat         B      = aij->B; /* off-diagonal part of the matrix */
640:   Mat_SeqAIJ *a      = (Mat_SeqAIJ *)A->data;
641:   Mat_SeqAIJ *b      = (Mat_SeqAIJ *)B->data;
642:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, col;
643:   PetscInt   *ailen = a->ilen, *aj = a->j;
644:   PetscInt   *bilen = b->ilen, *bj = b->j;
645:   PetscInt    am          = aij->A->rmap->n, j;
646:   PetscInt    diag_so_far = 0, dnz;
647:   PetscInt    offd_so_far = 0, onz;

649:   PetscFunctionBegin;
650:   /* Iterate over all rows of the matrix */
651:   for (j = 0; j < am; j++) {
652:     dnz = onz = 0;
653:     /*  Iterate over all non-zero columns of the current row */
654:     for (col = mat_i[j]; col < mat_i[j + 1]; col++) {
655:       /* If column is in the diagonal */
656:       if (mat_j[col] >= cstart && mat_j[col] < cend) {
657:         aj[diag_so_far++] = mat_j[col] - cstart;
658:         dnz++;
659:       } else { /* off-diagonal entries */
660:         bj[offd_so_far++] = mat_j[col];
661:         onz++;
662:       }
663:     }
664:     ailen[j] = dnz;
665:     bilen[j] = onz;
666:   }
667:   PetscFunctionReturn(PETSC_SUCCESS);
668: }

670: /*
671:     This function sets the local j, a and ilen arrays (of the diagonal and off-diagonal part) of an MPIAIJ-matrix.
672:     The values in mat_i have to be sorted and the values in mat_j have to be sorted for each row (CSR-like).
673:     No off-processor parts off the matrix are allowed here, they are set at a later point by MatSetValues_MPIAIJ.
674:     Also, mat->was_assembled has to be false, otherwise the statement aj[rowstart_diag+dnz_row] = mat_j[col] - cstart;
675:     would not be true and the more complex MatSetValues_MPIAIJ has to be used.
676: */
677: PetscErrorCode MatSetValues_MPIAIJ_CopyFromCSRFormat(Mat mat, const PetscInt mat_j[], const PetscInt mat_i[], const PetscScalar mat_a[])
678: {
679:   Mat_MPIAIJ  *aij  = (Mat_MPIAIJ *)mat->data;
680:   Mat          A    = aij->A; /* diagonal part of the matrix */
681:   Mat          B    = aij->B; /* off-diagonal part of the matrix */
682:   Mat_SeqAIJ  *aijd = (Mat_SeqAIJ *)aij->A->data, *aijo = (Mat_SeqAIJ *)aij->B->data;
683:   Mat_SeqAIJ  *a      = (Mat_SeqAIJ *)A->data;
684:   Mat_SeqAIJ  *b      = (Mat_SeqAIJ *)B->data;
685:   PetscInt     cstart = mat->cmap->rstart, cend = mat->cmap->rend;
686:   PetscInt    *ailen = a->ilen, *aj = a->j;
687:   PetscInt    *bilen = b->ilen, *bj = b->j;
688:   PetscInt     am          = aij->A->rmap->n, j;
689:   PetscInt    *full_diag_i = aijd->i, *full_offd_i = aijo->i; /* These variables can also include non-local elements, which are set at a later point. */
690:   PetscInt     col, dnz_row, onz_row, rowstart_diag, rowstart_offd;
691:   PetscScalar *aa = a->a, *ba = b->a;

693:   PetscFunctionBegin;
694:   /* Iterate over all rows of the matrix */
695:   for (j = 0; j < am; j++) {
696:     dnz_row = onz_row = 0;
697:     rowstart_offd     = full_offd_i[j];
698:     rowstart_diag     = full_diag_i[j];
699:     /*  Iterate over all non-zero columns of the current row */
700:     for (col = mat_i[j]; col < mat_i[j + 1]; col++) {
701:       /* If column is in the diagonal */
702:       if (mat_j[col] >= cstart && mat_j[col] < cend) {
703:         aj[rowstart_diag + dnz_row] = mat_j[col] - cstart;
704:         aa[rowstart_diag + dnz_row] = mat_a[col];
705:         dnz_row++;
706:       } else { /* off-diagonal entries */
707:         bj[rowstart_offd + onz_row] = mat_j[col];
708:         ba[rowstart_offd + onz_row] = mat_a[col];
709:         onz_row++;
710:       }
711:     }
712:     ailen[j] = dnz_row;
713:     bilen[j] = onz_row;
714:   }
715:   PetscFunctionReturn(PETSC_SUCCESS);
716: }

718: static PetscErrorCode MatGetValues_MPIAIJ(Mat mat, PetscInt m, const PetscInt idxm[], PetscInt n, const PetscInt idxn[], PetscScalar v[])
719: {
720:   Mat_MPIAIJ  *aij = (Mat_MPIAIJ *)mat->data;
721:   PetscInt     i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
722:   PetscInt     cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
723:   PetscBool    roworiented = aij->roworiented;
724:   PetscScalar *value;

726:   PetscFunctionBegin;
727:   for (i = 0; i < m; i++) {
728:     if (idxm[i] < 0) continue; /* negative row */
729:     PetscCheck(idxm[i] < mat->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Row too large: row %" PetscInt_FMT " max %" PetscInt_FMT, idxm[i], mat->rmap->N - 1);
730:     PetscCheck(idxm[i] >= rstart && idxm[i] < rend, PETSC_COMM_SELF, PETSC_ERR_SUP, "Only local values currently supported, row requested %" PetscInt_FMT " range [%" PetscInt_FMT " %" PetscInt_FMT ")", idxm[i], rstart, rend);
731:     row = idxm[i] - rstart;
732:     for (j = 0; j < n; j++) {
733:       if (idxn[j] < 0) continue; /* negative column */
734:       PetscCheck(idxn[j] < mat->cmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column too large: col %" PetscInt_FMT " max %" PetscInt_FMT, idxn[j], mat->cmap->N - 1);
735:       value = roworiented ? &v[j + i * n] : &v[i + j * m];
736:       if (idxn[j] >= cstart && idxn[j] < cend) {
737:         col = idxn[j] - cstart;
738:         PetscCall(MatGetValues(aij->A, 1, &row, 1, &col, value));
739:       } else {
740:         if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
741: #if PetscDefined(USE_CTABLE)
742:         PetscCall(PetscHMapIGetWithDefault(aij->colmap, idxn[j] + 1, 0, &col));
743:         col--;
744: #else
745:         col = aij->colmap[idxn[j]] - 1;
746: #endif
747:         if ((col < 0) || (aij->garray[col] != idxn[j])) *value = 0.0;
748:         else PetscCall(MatGetValues(aij->B, 1, &row, 1, &col, value));
749:       }
750:     }
751:   }
752:   PetscFunctionReturn(PETSC_SUCCESS);
753: }

755: static PetscErrorCode MatAssemblyBegin_MPIAIJ(Mat mat, MatAssemblyType mode)
756: {
757:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
758:   PetscInt    nstash, reallocs;

760:   PetscFunctionBegin;
761:   if (aij->donotstash || mat->nooffprocentries) PetscFunctionReturn(PETSC_SUCCESS);

763:   PetscCall(MatStashScatterBegin_Private(mat, &mat->stash, mat->rmap->range));
764:   PetscCall(MatStashGetInfo_Private(&mat->stash, &nstash, &reallocs));
765:   PetscCall(PetscInfo(mat, "Stash has %" PetscInt_FMT " entries, uses %" PetscInt_FMT " mallocs.\n", nstash, reallocs));
766:   PetscFunctionReturn(PETSC_SUCCESS);
767: }

769: PetscErrorCode MatAssemblyEnd_MPIAIJ(Mat mat, MatAssemblyType mode)
770: {
771:   Mat_MPIAIJ  *aij = (Mat_MPIAIJ *)mat->data;
772:   PetscMPIInt  n;
773:   PetscInt     i, j, rstart, ncols, flg;
774:   PetscInt    *row, *col;
775:   PetscBool    all_assembled;
776:   PetscScalar *val;

778:   /* do not use 'b = (Mat_SeqAIJ*)aij->B->data' as B can be reset in disassembly */

780:   PetscFunctionBegin;
781:   if (!aij->donotstash && !mat->nooffprocentries) {
782:     while (1) {
783:       PetscCall(MatStashScatterGetMesg_Private(&mat->stash, &n, &row, &col, &val, &flg));
784:       if (!flg) break;

786:       for (i = 0; i < n;) {
787:         /* Now identify the consecutive vals belonging to the same row */
788:         for (j = i, rstart = row[j]; j < n; j++) {
789:           if (row[j] != rstart) break;
790:         }
791:         if (j < n) ncols = j - i;
792:         else ncols = n - i;
793:         /* Now assemble all these values with a single function call */
794:         PetscCall(MatSetValues_MPIAIJ(mat, 1, row + i, ncols, col + i, val + i, mat->insertmode));
795:         i = j;
796:       }
797:     }
798:     PetscCall(MatStashScatterEnd_Private(&mat->stash));
799:   }
800: #if PetscDefined(HAVE_DEVICE)
801:   if (mat->offloadmask == PETSC_OFFLOAD_CPU) aij->A->offloadmask = PETSC_OFFLOAD_CPU;
802:   /* We call MatBindToCPU() on aij->A and aij->B here, because if MatBindToCPU_MPIAIJ() is called before assembly, it cannot bind these. */
803:   if (mat->boundtocpu) {
804:     PetscCall(MatBindToCPU(aij->A, PETSC_TRUE));
805:     PetscCall(MatBindToCPU(aij->B, PETSC_TRUE));
806:   }
807: #endif
808:   PetscCall(MatAssemblyBegin(aij->A, mode));
809:   PetscCall(MatAssemblyEnd(aij->A, mode));

811:   /* determine if any process has disassembled, if so we must
812:      also disassemble ourself, in order that we may reassemble. */
813:   /*
814:      if nonzero structure of submatrix B cannot change then we know that
815:      no process disassembled thus we can skip this stuff
816:   */
817:   if (!((Mat_SeqAIJ *)aij->B->data)->nonew) {
818:     PetscCallMPI(MPIU_Allreduce(&mat->was_assembled, &all_assembled, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));
819:     if (mat->was_assembled && !all_assembled) { /* mat on this rank has reduced off-diag B with local col ids, but globally it does not */
820:       PetscCall(MatDisAssemble_MPIAIJ(mat, PETSC_FALSE));
821:     }
822:   }
823:   if (!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) PetscCall(MatSetUpMultiply_MPIAIJ(mat));
824:   PetscCall(MatSetOption(aij->B, MAT_USE_INODES, PETSC_FALSE));
825: #if PetscDefined(HAVE_DEVICE)
826:   if (mat->offloadmask == PETSC_OFFLOAD_CPU && aij->B->offloadmask != PETSC_OFFLOAD_UNALLOCATED) aij->B->offloadmask = PETSC_OFFLOAD_CPU;
827: #endif
828:   PetscCall(MatAssemblyBegin(aij->B, mode));
829:   PetscCall(MatAssemblyEnd(aij->B, mode));

831:   PetscCall(PetscFree2(aij->rowvalues, aij->rowindices));

833:   aij->rowvalues = NULL;

835:   PetscCall(VecDestroy(&aij->diag));

837:   /* if no new nonzero locations are allowed in matrix then only set the matrix state the first time through */
838:   if ((!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) || !((Mat_SeqAIJ *)aij->A->data)->nonew) {
839:     mat->nonzerostate = aij->A->nonzerostate + aij->B->nonzerostate;
840:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &mat->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)mat)));
841:   }
842: #if PetscDefined(HAVE_DEVICE)
843:   mat->offloadmask = PETSC_OFFLOAD_BOTH;
844: #endif
845:   PetscFunctionReturn(PETSC_SUCCESS);
846: }

848: static PetscErrorCode MatZeroEntries_MPIAIJ(Mat A)
849: {
850:   Mat_MPIAIJ *l = (Mat_MPIAIJ *)A->data;

852:   PetscFunctionBegin;
853:   PetscCall(MatZeroEntries(l->A));
854:   PetscCall(MatZeroEntries(l->B));
855:   PetscFunctionReturn(PETSC_SUCCESS);
856: }

858: static PetscErrorCode MatZeroRows_MPIAIJ(Mat A, PetscInt N, const PetscInt rows[], PetscScalar diag, Vec x, Vec b)
859: {
860:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)A->data;
861:   PetscInt   *lrows;
862:   PetscInt    r, len;
863:   PetscBool   cong;

865:   PetscFunctionBegin;
866:   /* get locally owned rows */
867:   PetscCall(MatZeroRowsMapLocal_Private(A, N, rows, &len, &lrows));
868:   PetscCall(MatHasCongruentLayouts(A, &cong));
869:   /* fix right-hand side if needed */
870:   if (x && b) {
871:     const PetscScalar *xx;
872:     PetscScalar       *bb;

874:     PetscCheck(cong, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Need matching row/col layout");
875:     PetscCall(VecGetArrayRead(x, &xx));
876:     PetscCall(VecGetArray(b, &bb));
877:     for (r = 0; r < len; ++r) bb[lrows[r]] = diag * xx[lrows[r]];
878:     PetscCall(VecRestoreArrayRead(x, &xx));
879:     PetscCall(VecRestoreArray(b, &bb));
880:   }

882:   if (diag != 0.0 && cong) {
883:     PetscCall(MatZeroRows(mat->A, len, lrows, diag, NULL, NULL));
884:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
885:   } else if (diag != 0.0) { /* non-square or non congruent layouts -> if keepnonzeropattern is false, we allow for new insertion */
886:     Mat_SeqAIJ *aijA = (Mat_SeqAIJ *)mat->A->data;
887:     Mat_SeqAIJ *aijB = (Mat_SeqAIJ *)mat->B->data;
888:     PetscInt    nnwA, nnwB;
889:     PetscBool   nnzA, nnzB;

891:     nnwA = aijA->nonew;
892:     nnwB = aijB->nonew;
893:     nnzA = aijA->keepnonzeropattern;
894:     nnzB = aijB->keepnonzeropattern;
895:     if (!nnzA) {
896:       PetscCall(PetscInfo(mat->A, "Requested to not keep the pattern and add a nonzero diagonal; may encounter reallocations on diagonal block.\n"));
897:       aijA->nonew = 0;
898:     }
899:     if (!nnzB) {
900:       PetscCall(PetscInfo(mat->B, "Requested to not keep the pattern and add a nonzero diagonal; may encounter reallocations on off-diagonal block.\n"));
901:       aijB->nonew = 0;
902:     }
903:     /* Must zero here before the next loop */
904:     PetscCall(MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL));
905:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
906:     for (r = 0; r < len; ++r) {
907:       const PetscInt row = lrows[r] + A->rmap->rstart;
908:       if (row >= A->cmap->N) continue;
909:       PetscCall(MatSetValues(A, 1, &row, 1, &row, &diag, INSERT_VALUES));
910:     }
911:     aijA->nonew = nnwA;
912:     aijB->nonew = nnwB;
913:   } else {
914:     PetscCall(MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL));
915:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
916:   }
917:   PetscCall(PetscFree(lrows));
918:   PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
919:   PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));

921:   /* only change matrix nonzero state if pattern was allowed to be changed */
922:   if (!((Mat_SeqAIJ *)mat->A->data)->keepnonzeropattern || !((Mat_SeqAIJ *)mat->A->data)->nonew) {
923:     A->nonzerostate = mat->A->nonzerostate + mat->B->nonzerostate;
924:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &A->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)A)));
925:   }
926:   PetscFunctionReturn(PETSC_SUCCESS);
927: }

929: static PetscErrorCode MatZeroRowsColumns_MPIAIJ(Mat A, PetscInt N, const PetscInt rows[], PetscScalar diag, Vec x, Vec b)
930: {
931:   Mat_MPIAIJ        *l = (Mat_MPIAIJ *)A->data;
932:   PetscInt           n = A->rmap->n;
933:   PetscInt           i, j, r, m, len = 0;
934:   PetscInt          *lrows, *owners = A->rmap->range;
935:   PetscMPIInt        p = 0;
936:   PetscSFNode       *rrows;
937:   PetscSF            sf;
938:   const PetscScalar *xx;
939:   PetscScalar       *bb, *mask, *aij_a;
940:   Vec                xmask, lmask;
941:   Mat_SeqAIJ        *aij = (Mat_SeqAIJ *)l->B->data;
942:   const PetscInt    *aj, *ii, *ridx;
943:   PetscScalar       *aa;

945:   PetscFunctionBegin;
946:   /* Create SF where leaves are input rows and roots are owned rows */
947:   PetscCall(PetscMalloc1(n, &lrows));
948:   for (r = 0; r < n; ++r) lrows[r] = -1;
949:   PetscCall(PetscMalloc1(N, &rrows));
950:   for (r = 0; r < N; ++r) {
951:     const PetscInt idx = rows[r];
952:     PetscCheck(idx >= 0 && A->rmap->N > idx, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Row %" PetscInt_FMT " out of range [0,%" PetscInt_FMT ")", idx, A->rmap->N);
953:     if (idx < owners[p] || owners[p + 1] <= idx) { /* short-circuit the search if the last p owns this row too */
954:       PetscCall(PetscLayoutFindOwner(A->rmap, idx, &p));
955:     }
956:     rrows[r].rank  = p;
957:     rrows[r].index = rows[r] - owners[p];
958:   }
959:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
960:   PetscCall(PetscSFSetGraph(sf, n, N, NULL, PETSC_OWN_POINTER, rrows, PETSC_OWN_POINTER));
961:   /* Collect flags for rows to be zeroed */
962:   PetscCall(PetscSFReduceBegin(sf, MPIU_INT, (PetscInt *)rows, lrows, MPI_LOR));
963:   PetscCall(PetscSFReduceEnd(sf, MPIU_INT, (PetscInt *)rows, lrows, MPI_LOR));
964:   PetscCall(PetscSFDestroy(&sf));
965:   /* Compress and put in row numbers */
966:   for (r = 0; r < n; ++r)
967:     if (lrows[r] >= 0) lrows[len++] = r;
968:   /* zero diagonal part of matrix */
969:   PetscCall(MatZeroRowsColumns(l->A, len, lrows, diag, x, b));
970:   /* handle off-diagonal part of matrix */
971:   PetscCall(MatCreateVecs(A, &xmask, NULL));
972:   PetscCall(VecDuplicate(l->lvec, &lmask));
973:   PetscCall(VecGetArray(xmask, &bb));
974:   for (i = 0; i < len; i++) bb[lrows[i]] = 1;
975:   PetscCall(VecRestoreArray(xmask, &bb));
976:   PetscCall(VecScatterBegin(l->Mvctx, xmask, lmask, ADD_VALUES, SCATTER_FORWARD));
977:   PetscCall(VecScatterEnd(l->Mvctx, xmask, lmask, ADD_VALUES, SCATTER_FORWARD));
978:   PetscCall(VecDestroy(&xmask));
979:   if (x && b) { /* this code is buggy when the row and column layout don't match */
980:     PetscBool cong;

982:     PetscCall(MatHasCongruentLayouts(A, &cong));
983:     PetscCheck(cong, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Need matching row/col layout");
984:     PetscCall(VecScatterBegin(l->Mvctx, x, l->lvec, INSERT_VALUES, SCATTER_FORWARD));
985:     PetscCall(VecScatterEnd(l->Mvctx, x, l->lvec, INSERT_VALUES, SCATTER_FORWARD));
986:     PetscCall(VecGetArrayRead(l->lvec, &xx));
987:     PetscCall(VecGetArray(b, &bb));
988:   }
989:   PetscCall(VecGetArray(lmask, &mask));
990:   /* remove zeroed rows of off-diagonal matrix */
991:   PetscCall(MatSeqAIJGetArray(l->B, &aij_a));
992:   ii = aij->i;
993:   for (i = 0; i < len; i++) PetscCall(PetscArrayzero(PetscSafePointerPlusOffset(aij_a, ii[lrows[i]]), ii[lrows[i] + 1] - ii[lrows[i]]));
994:   /* loop over all elements of off process part of matrix zeroing removed columns*/
995:   if (aij->compressedrow.use) {
996:     m    = aij->compressedrow.nrows;
997:     ii   = aij->compressedrow.i;
998:     ridx = aij->compressedrow.rindex;
999:     for (i = 0; i < m; i++) {
1000:       n  = ii[i + 1] - ii[i];
1001:       aj = aij->j + ii[i];
1002:       aa = aij_a + ii[i];

1004:       for (j = 0; j < n; j++) {
1005:         if (PetscAbsScalar(mask[*aj])) {
1006:           if (b) bb[*ridx] -= *aa * xx[*aj];
1007:           *aa = 0.0;
1008:         }
1009:         aa++;
1010:         aj++;
1011:       }
1012:       ridx++;
1013:     }
1014:   } else { /* do not use compressed row format */
1015:     m = l->B->rmap->n;
1016:     for (i = 0; i < m; i++) {
1017:       n  = ii[i + 1] - ii[i];
1018:       aj = aij->j + ii[i];
1019:       aa = aij_a + ii[i];
1020:       for (j = 0; j < n; j++) {
1021:         if (PetscAbsScalar(mask[*aj])) {
1022:           if (b) bb[i] -= *aa * xx[*aj];
1023:           *aa = 0.0;
1024:         }
1025:         aa++;
1026:         aj++;
1027:       }
1028:     }
1029:   }
1030:   if (x && b) {
1031:     PetscCall(VecRestoreArray(b, &bb));
1032:     PetscCall(VecRestoreArrayRead(l->lvec, &xx));
1033:   }
1034:   PetscCall(MatSeqAIJRestoreArray(l->B, &aij_a));
1035:   PetscCall(VecRestoreArray(lmask, &mask));
1036:   PetscCall(VecDestroy(&lmask));
1037:   PetscCall(PetscFree(lrows));

1039:   /* only change matrix nonzero state if pattern was allowed to be changed */
1040:   if (!((Mat_SeqAIJ *)l->A->data)->nonew) {
1041:     A->nonzerostate = l->A->nonzerostate + l->B->nonzerostate;
1042:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &A->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)A)));
1043:   }
1044:   PetscFunctionReturn(PETSC_SUCCESS);
1045: }

1047: static PetscErrorCode MatMult_MPIAIJ(Mat A, Vec xx, Vec yy)
1048: {
1049:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
1050:   PetscInt    nt;
1051:   VecScatter  Mvctx = a->Mvctx;

1053:   PetscFunctionBegin;
1054:   PetscCall(VecGetLocalSize(xx, &nt));
1055:   PetscCheck(nt == A->cmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Incompatible partition of A (%" PetscInt_FMT ") and xx (%" PetscInt_FMT ")", A->cmap->n, nt);
1056:   PetscCall(VecScatterBegin(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1057:   PetscUseTypeMethod(a->A, mult, xx, yy);
1058:   PetscCall(VecScatterEnd(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1059:   PetscUseTypeMethod(a->B, multadd, a->lvec, yy, yy);
1060:   PetscFunctionReturn(PETSC_SUCCESS);
1061: }

1063: static PetscErrorCode MatMultDiagonalBlock_MPIAIJ(Mat A, Vec bb, Vec xx)
1064: {
1065:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1067:   PetscFunctionBegin;
1068:   PetscCall(MatMultDiagonalBlock(a->A, bb, xx));
1069:   PetscFunctionReturn(PETSC_SUCCESS);
1070: }

1072: static PetscErrorCode MatMultAdd_MPIAIJ(Mat A, Vec xx, Vec yy, Vec zz)
1073: {
1074:   Mat_MPIAIJ *a     = (Mat_MPIAIJ *)A->data;
1075:   VecScatter  Mvctx = a->Mvctx;

1077:   PetscFunctionBegin;
1078:   PetscCall(VecScatterBegin(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1079:   PetscUseTypeMethod(a->A, multadd, xx, yy, zz);
1080:   PetscCall(VecScatterEnd(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1081:   PetscUseTypeMethod(a->B, multadd, a->lvec, zz, zz);
1082:   PetscFunctionReturn(PETSC_SUCCESS);
1083: }

1085: static PetscErrorCode MatMultTranspose_MPIAIJ(Mat A, Vec xx, Vec yy)
1086: {
1087:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1089:   PetscFunctionBegin;
1090:   /* do nondiagonal part */
1091:   PetscUseTypeMethod(a->B, multtranspose, xx, a->lvec);
1092:   /* do local part */
1093:   PetscUseTypeMethod(a->A, multtranspose, xx, yy);
1094:   /* add partial results together */
1095:   PetscCall(VecScatterBegin(a->Mvctx, a->lvec, yy, ADD_VALUES, SCATTER_REVERSE));
1096:   PetscCall(VecScatterEnd(a->Mvctx, a->lvec, yy, ADD_VALUES, SCATTER_REVERSE));
1097:   PetscFunctionReturn(PETSC_SUCCESS);
1098: }

1100: static PetscErrorCode MatIsTranspose_MPIAIJ(Mat Amat, Mat Bmat, PetscReal tol, PetscBool *f)
1101: {
1102:   MPI_Comm    comm;
1103:   Mat_MPIAIJ *Aij = (Mat_MPIAIJ *)Amat->data, *Bij = (Mat_MPIAIJ *)Bmat->data;
1104:   Mat         Adia = Aij->A, Bdia = Bij->A, Aoff, Boff, *Aoffs, *Boffs;
1105:   IS          Me, Notme;
1106:   PetscInt    M, N, first, last, *notme, i;
1107:   PetscMPIInt size;

1109:   PetscFunctionBegin;
1110:   /* Easy test: symmetric diagonal block */
1111:   PetscCall(MatIsTranspose(Adia, Bdia, tol, f));
1112:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, f, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)Amat)));
1113:   if (!*f) PetscFunctionReturn(PETSC_SUCCESS);
1114:   PetscCall(PetscObjectGetComm((PetscObject)Amat, &comm));
1115:   PetscCallMPI(MPI_Comm_size(comm, &size));
1116:   if (size == 1) PetscFunctionReturn(PETSC_SUCCESS);

1118:   /* Hard test: off-diagonal block. This takes a MatCreateSubMatrix. */
1119:   PetscCall(MatGetSize(Amat, &M, &N));
1120:   PetscCall(MatGetOwnershipRange(Amat, &first, &last));
1121:   PetscCall(PetscMalloc1(N - last + first, &notme));
1122:   for (i = 0; i < first; i++) notme[i] = i;
1123:   for (i = last; i < M; i++) notme[i - last + first] = i;
1124:   PetscCall(ISCreateGeneral(MPI_COMM_SELF, N - last + first, notme, PETSC_COPY_VALUES, &Notme));
1125:   PetscCall(ISCreateStride(MPI_COMM_SELF, last - first, first, 1, &Me));
1126:   PetscCall(MatCreateSubMatrices(Amat, 1, &Me, &Notme, MAT_INITIAL_MATRIX, &Aoffs));
1127:   Aoff = Aoffs[0];
1128:   PetscCall(MatCreateSubMatrices(Bmat, 1, &Notme, &Me, MAT_INITIAL_MATRIX, &Boffs));
1129:   Boff = Boffs[0];
1130:   PetscCall(MatIsTranspose(Aoff, Boff, tol, f));
1131:   PetscCall(MatDestroyMatrices(1, &Aoffs));
1132:   PetscCall(MatDestroyMatrices(1, &Boffs));
1133:   PetscCall(ISDestroy(&Me));
1134:   PetscCall(ISDestroy(&Notme));
1135:   PetscCall(PetscFree(notme));
1136:   PetscFunctionReturn(PETSC_SUCCESS);
1137: }

1139: static PetscErrorCode MatMultTransposeAdd_MPIAIJ(Mat A, Vec xx, Vec yy, Vec zz)
1140: {
1141:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1143:   PetscFunctionBegin;
1144:   /* do nondiagonal part */
1145:   PetscUseTypeMethod(a->B, multtranspose, xx, a->lvec);
1146:   /* do local part */
1147:   PetscUseTypeMethod(a->A, multtransposeadd, xx, yy, zz);
1148:   /* add partial results together */
1149:   PetscCall(VecScatterBegin(a->Mvctx, a->lvec, zz, ADD_VALUES, SCATTER_REVERSE));
1150:   PetscCall(VecScatterEnd(a->Mvctx, a->lvec, zz, ADD_VALUES, SCATTER_REVERSE));
1151:   PetscFunctionReturn(PETSC_SUCCESS);
1152: }

1154: /*
1155:   This only works correctly for square matrices where the subblock A->A is the
1156:    diagonal block
1157: */
1158: static PetscErrorCode MatGetDiagonal_MPIAIJ(Mat A, Vec v)
1159: {
1160:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1162:   PetscFunctionBegin;
1163:   PetscCheck(A->rmap->N == A->cmap->N, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Supports only square matrix where A->A is diag block");
1164:   PetscCheck(A->rmap->rstart == A->cmap->rstart && A->rmap->rend == A->cmap->rend, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "row partition must equal col partition");
1165:   PetscCall(MatGetDiagonal(a->A, v));
1166:   PetscFunctionReturn(PETSC_SUCCESS);
1167: }

1169: static PetscErrorCode MatScale_MPIAIJ(Mat A, PetscScalar aa)
1170: {
1171:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1173:   PetscFunctionBegin;
1174:   PetscCall(MatScale(a->A, aa));
1175:   PetscCall(MatScale(a->B, aa));
1176:   PetscFunctionReturn(PETSC_SUCCESS);
1177: }

1179: static PetscErrorCode MatView_MPIAIJ_Binary(Mat mat, PetscViewer viewer)
1180: {
1181:   Mat_MPIAIJ        *aij    = (Mat_MPIAIJ *)mat->data;
1182:   Mat_SeqAIJ        *A      = (Mat_SeqAIJ *)aij->A->data;
1183:   Mat_SeqAIJ        *B      = (Mat_SeqAIJ *)aij->B->data;
1184:   const PetscInt    *garray = aij->garray;
1185:   const PetscScalar *aa, *ba;
1186:   PetscInt           header[4], M, N, m, rs, cs, cnt, i, ja, jb;
1187:   PetscInt64         nz, hnz;
1188:   PetscInt          *rowlens;
1189:   PetscInt          *colidxs;
1190:   PetscScalar       *matvals;
1191:   PetscMPIInt        rank;

1193:   PetscFunctionBegin;
1194:   PetscCall(PetscViewerSetUp(viewer));

1196:   M  = mat->rmap->N;
1197:   N  = mat->cmap->N;
1198:   m  = mat->rmap->n;
1199:   rs = mat->rmap->rstart;
1200:   cs = mat->cmap->rstart;
1201:   nz = A->nz + B->nz;

1203:   /* write matrix header */
1204:   header[0] = MAT_FILE_CLASSID;
1205:   header[1] = M;
1206:   header[2] = N;
1207:   PetscCallMPI(MPI_Reduce(&nz, &hnz, 1, MPIU_INT64, MPI_SUM, 0, PetscObjectComm((PetscObject)mat)));
1208:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)mat), &rank));
1209:   if (rank == 0) PetscCall(PetscIntCast(hnz, &header[3]));
1210:   PetscCall(PetscViewerBinaryWrite(viewer, header, 4, PETSC_INT));

1212:   /* fill in and store row lengths  */
1213:   PetscCall(PetscMalloc1(m, &rowlens));
1214:   for (i = 0; i < m; i++) rowlens[i] = A->i[i + 1] - A->i[i] + B->i[i + 1] - B->i[i];
1215:   PetscCall(PetscViewerBinaryWriteAll(viewer, rowlens, m, rs, M, PETSC_INT));
1216:   PetscCall(PetscFree(rowlens));

1218:   /* fill in and store column indices */
1219:   PetscCall(PetscMalloc1(nz, &colidxs));
1220:   for (cnt = 0, i = 0; i < m; i++) {
1221:     for (jb = B->i[i]; jb < B->i[i + 1]; jb++) {
1222:       if (garray[B->j[jb]] > cs) break;
1223:       colidxs[cnt++] = garray[B->j[jb]];
1224:     }
1225:     for (ja = A->i[i]; ja < A->i[i + 1]; ja++) colidxs[cnt++] = A->j[ja] + cs;
1226:     for (; jb < B->i[i + 1]; jb++) colidxs[cnt++] = garray[B->j[jb]];
1227:   }
1228:   PetscCheck(cnt == nz, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Internal PETSc error: cnt = %" PetscInt_FMT " nz = %" PetscInt64_FMT, cnt, nz);
1229:   PetscCall(PetscViewerBinaryWriteAll(viewer, colidxs, nz, PETSC_DETERMINE, PETSC_DETERMINE, PETSC_INT));
1230:   PetscCall(PetscFree(colidxs));

1232:   /* fill in and store nonzero values */
1233:   PetscCall(MatSeqAIJGetArrayRead(aij->A, &aa));
1234:   PetscCall(MatSeqAIJGetArrayRead(aij->B, &ba));
1235:   PetscCall(PetscMalloc1(nz, &matvals));
1236:   for (cnt = 0, i = 0; i < m; i++) {
1237:     for (jb = B->i[i]; jb < B->i[i + 1]; jb++) {
1238:       if (garray[B->j[jb]] > cs) break;
1239:       matvals[cnt++] = ba[jb];
1240:     }
1241:     for (ja = A->i[i]; ja < A->i[i + 1]; ja++) matvals[cnt++] = aa[ja];
1242:     for (; jb < B->i[i + 1]; jb++) matvals[cnt++] = ba[jb];
1243:   }
1244:   PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &aa));
1245:   PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &ba));
1246:   PetscCheck(cnt == nz, PETSC_COMM_SELF, PETSC_ERR_LIB, "Internal PETSc error: cnt = %" PetscInt_FMT " nz = %" PetscInt64_FMT, cnt, nz);
1247:   PetscCall(PetscViewerBinaryWriteAll(viewer, matvals, nz, PETSC_DETERMINE, PETSC_DETERMINE, PETSC_SCALAR));
1248:   PetscCall(PetscFree(matvals));

1250:   /* write block size option to the viewer's .info file */
1251:   PetscCall(MatView_Binary_BlockSizes(mat, viewer));
1252:   PetscFunctionReturn(PETSC_SUCCESS);
1253: }

1255: #include <petscdraw.h>
1256: static PetscErrorCode MatView_MPIAIJ_ASCIIorDraworSocket(Mat mat, PetscViewer viewer)
1257: {
1258:   Mat_MPIAIJ       *aij  = (Mat_MPIAIJ *)mat->data;
1259:   PetscMPIInt       rank = aij->rank, size = aij->size;
1260:   PetscBool         isdraw, isascii, isbinary;
1261:   PetscViewer       sviewer;
1262:   PetscViewerFormat format;

1264:   PetscFunctionBegin;
1265:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERDRAW, &isdraw));
1266:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &isascii));
1267:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
1268:   if (isascii) {
1269:     PetscCall(PetscViewerGetFormat(viewer, &format));
1270:     if (format == PETSC_VIEWER_LOAD_BALANCE) {
1271:       PetscInt i, nmax = 0, nmin = PETSC_INT_MAX, navg = 0, *nz, nzlocal = ((Mat_SeqAIJ *)aij->A->data)->nz + ((Mat_SeqAIJ *)aij->B->data)->nz;
1272:       PetscCall(PetscMalloc1(size, &nz));
1273:       PetscCallMPI(MPI_Allgather(&nzlocal, 1, MPIU_INT, nz, 1, MPIU_INT, PetscObjectComm((PetscObject)mat)));
1274:       for (i = 0; i < size; i++) {
1275:         nmax = PetscMax(nmax, nz[i]);
1276:         nmin = PetscMin(nmin, nz[i]);
1277:         navg += nz[i];
1278:       }
1279:       PetscCall(PetscFree(nz));
1280:       navg = navg / size;
1281:       PetscCall(PetscViewerASCIIPrintf(viewer, "Load Balance - Nonzeros: Min %" PetscInt_FMT "  avg %" PetscInt_FMT "  max %" PetscInt_FMT "\n", nmin, navg, nmax));
1282:       PetscFunctionReturn(PETSC_SUCCESS);
1283:     }
1284:     PetscCall(PetscViewerGetFormat(viewer, &format));
1285:     if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
1286:       MatInfo   info;
1287:       PetscInt *inodes = NULL;

1289:       PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)mat), &rank));
1290:       PetscCall(MatGetInfo(mat, MAT_LOCAL, &info));
1291:       PetscCall(MatInodeGetInodeSizes(aij->A, NULL, &inodes, NULL));
1292:       PetscCall(PetscViewerASCIIPushSynchronized(viewer));
1293:       if (!inodes) {
1294:         PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] Local rows %" PetscInt_FMT " nz %" PetscInt_FMT " nz alloced %" PetscInt_FMT " mem %g, not using I-node routines\n", rank, mat->rmap->n, (PetscInt)info.nz_used, (PetscInt)info.nz_allocated,
1295:                                                      info.memory));
1296:       } else {
1297:         PetscCall(
1298:           PetscViewerASCIISynchronizedPrintf(viewer, "[%d] Local rows %" PetscInt_FMT " nz %" PetscInt_FMT " nz alloced %" PetscInt_FMT " mem %g, using I-node routines\n", rank, mat->rmap->n, (PetscInt)info.nz_used, (PetscInt)info.nz_allocated, info.memory));
1299:       }
1300:       PetscCall(MatGetInfo(aij->A, MAT_LOCAL, &info));
1301:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] on-diagonal part: nz %" PetscInt_FMT " \n", rank, (PetscInt)info.nz_used));
1302:       PetscCall(MatGetInfo(aij->B, MAT_LOCAL, &info));
1303:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] off-diagonal part: nz %" PetscInt_FMT " \n", rank, (PetscInt)info.nz_used));
1304:       PetscCall(PetscViewerFlush(viewer));
1305:       PetscCall(PetscViewerASCIIPopSynchronized(viewer));
1306:       PetscCall(PetscViewerASCIIPrintf(viewer, "Information on VecScatter used in matrix-vector product: \n"));
1307:       PetscCall(VecScatterView(aij->Mvctx, viewer));
1308:       PetscFunctionReturn(PETSC_SUCCESS);
1309:     } else if (format == PETSC_VIEWER_ASCII_INFO) {
1310:       PetscInt inodecount, inodelimit, *inodes;
1311:       PetscCall(MatInodeGetInodeSizes(aij->A, &inodecount, &inodes, &inodelimit));
1312:       if (inodes) {
1313:         PetscCall(PetscViewerASCIIPrintf(viewer, "using I-node (on process 0) routines: found %" PetscInt_FMT " nodes, limit used is %" PetscInt_FMT "\n", inodecount, inodelimit));
1314:       } else {
1315:         PetscCall(PetscViewerASCIIPrintf(viewer, "not using I-node (on process 0) routines\n"));
1316:       }
1317:       PetscFunctionReturn(PETSC_SUCCESS);
1318:     } else if (format == PETSC_VIEWER_ASCII_FACTOR_INFO) {
1319:       PetscFunctionReturn(PETSC_SUCCESS);
1320:     }
1321:   } else if (isbinary) {
1322:     if (size == 1) {
1323:       PetscCall(PetscObjectSetName((PetscObject)aij->A, ((PetscObject)mat)->name));
1324:       PetscCall(MatView(aij->A, viewer));
1325:     } else {
1326:       PetscCall(MatView_MPIAIJ_Binary(mat, viewer));
1327:     }
1328:     PetscFunctionReturn(PETSC_SUCCESS);
1329:   } else if (isascii && size == 1) {
1330:     PetscCall(PetscObjectSetName((PetscObject)aij->A, ((PetscObject)mat)->name));
1331:     PetscCall(MatView(aij->A, viewer));
1332:     PetscFunctionReturn(PETSC_SUCCESS);
1333:   } else if (isdraw) {
1334:     PetscDraw draw;
1335:     PetscBool isnull;
1336:     PetscCall(PetscViewerDrawGetDraw(viewer, 0, &draw));
1337:     PetscCall(PetscDrawIsNull(draw, &isnull));
1338:     if (isnull) PetscFunctionReturn(PETSC_SUCCESS);
1339:   }

1341:   { /* assemble the entire matrix onto first processor */
1342:     Mat A = NULL, Av;
1343:     IS  isrow, iscol;

1345:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat), rank == 0 ? mat->rmap->N : 0, 0, 1, &isrow));
1346:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat), rank == 0 ? mat->cmap->N : 0, 0, 1, &iscol));
1347:     PetscCall(MatCreateSubMatrix(mat, isrow, iscol, MAT_INITIAL_MATRIX, &A));
1348:     PetscCall(MatMPIAIJGetSeqAIJ(A, &Av, NULL, NULL));
1349:     /*  The commented code uses MatCreateSubMatrices instead */
1350:     /*
1351:     Mat *AA, A = NULL, Av;
1352:     IS  isrow,iscol;

1354:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat),rank == 0 ? mat->rmap->N : 0,0,1,&isrow));
1355:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat),rank == 0 ? mat->cmap->N : 0,0,1,&iscol));
1356:     PetscCall(MatCreateSubMatrices(mat,1,&isrow,&iscol,MAT_INITIAL_MATRIX,&AA));
1357:     if (rank == 0) {
1358:        PetscCall(PetscObjectReference((PetscObject)AA[0]));
1359:        A    = AA[0];
1360:        Av   = AA[0];
1361:     }
1362:     PetscCall(MatDestroySubMatrices(1,&AA));
1363: */
1364:     PetscCall(ISDestroy(&iscol));
1365:     PetscCall(ISDestroy(&isrow));
1366:     /*
1367:        Everyone has to call to draw the matrix since the graphics waits are
1368:        synchronized across all processors that share the PetscDraw object
1369:     */
1370:     PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
1371:     if (rank == 0) {
1372:       if (((PetscObject)mat)->name) PetscCall(PetscObjectSetName((PetscObject)Av, ((PetscObject)mat)->name));
1373:       PetscCall(MatView_SeqAIJ(Av, sviewer));
1374:     }
1375:     PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
1376:     PetscCall(MatDestroy(&A));
1377:   }
1378:   PetscFunctionReturn(PETSC_SUCCESS);
1379: }

1381: PetscErrorCode MatView_MPIAIJ(Mat mat, PetscViewer viewer)
1382: {
1383:   PetscBool isascii, isdraw, issocket, isbinary;

1385:   PetscFunctionBegin;
1386:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &isascii));
1387:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERDRAW, &isdraw));
1388:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
1389:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERSOCKET, &issocket));
1390:   if (isascii || isdraw || isbinary || issocket) PetscCall(MatView_MPIAIJ_ASCIIorDraworSocket(mat, viewer));
1391:   PetscFunctionReturn(PETSC_SUCCESS);
1392: }

1394: static PetscErrorCode MatSOR_MPIAIJ(Mat matin, Vec bb, PetscReal omega, MatSORType flag, PetscReal fshift, PetscInt its, PetscInt lits, Vec xx)
1395: {
1396:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)matin->data;
1397:   Vec         bb1 = NULL;
1398:   PetscBool   hasop;

1400:   PetscFunctionBegin;
1401:   if (flag == SOR_APPLY_UPPER) {
1402:     PetscUseTypeMethod(mat->A, sor, bb, omega, flag, fshift, lits, 1, xx);
1403:     PetscFunctionReturn(PETSC_SUCCESS);
1404:   }

1406:   if (its > 1 || ~flag & SOR_ZERO_INITIAL_GUESS || flag & SOR_EISENSTAT) PetscCall(VecDuplicate(bb, &bb1));

1408:   if ((flag & SOR_LOCAL_SYMMETRIC_SWEEP) == SOR_LOCAL_SYMMETRIC_SWEEP) {
1409:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1410:       PetscUseTypeMethod(mat->A, sor, bb, omega, flag, fshift, lits, 1, xx);
1411:       its--;
1412:     }

1414:     while (its--) {
1415:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1416:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1418:       /* update rhs: bb1 = bb - B*x */
1419:       PetscCall(VecScale(mat->lvec, -1.0));
1420:       PetscUseTypeMethod(mat->B, multadd, mat->lvec, bb, bb1);

1422:       /* local sweep */
1423:       PetscUseTypeMethod(mat->A, sor, bb1, omega, SOR_SYMMETRIC_SWEEP, fshift, lits, 1, xx);
1424:     }
1425:   } else if (flag & SOR_LOCAL_FORWARD_SWEEP) {
1426:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1427:       PetscUseTypeMethod(mat->A, sor, bb, omega, flag, fshift, lits, 1, xx);
1428:       its--;
1429:     }
1430:     while (its--) {
1431:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1432:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1434:       /* update rhs: bb1 = bb - B*x */
1435:       PetscCall(VecScale(mat->lvec, -1.0));
1436:       PetscUseTypeMethod(mat->B, multadd, mat->lvec, bb, bb1);

1438:       /* local sweep */
1439:       PetscUseTypeMethod(mat->A, sor, bb1, omega, SOR_FORWARD_SWEEP, fshift, lits, 1, xx);
1440:     }
1441:   } else if (flag & SOR_LOCAL_BACKWARD_SWEEP) {
1442:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1443:       PetscUseTypeMethod(mat->A, sor, bb, omega, flag, fshift, lits, 1, xx);
1444:       its--;
1445:     }
1446:     while (its--) {
1447:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1448:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1450:       /* update rhs: bb1 = bb - B*x */
1451:       PetscCall(VecScale(mat->lvec, -1.0));
1452:       PetscUseTypeMethod(mat->B, multadd, mat->lvec, bb, bb1);

1454:       /* local sweep */
1455:       PetscUseTypeMethod(mat->A, sor, bb1, omega, SOR_BACKWARD_SWEEP, fshift, lits, 1, xx);
1456:     }
1457:   } else if (flag & SOR_EISENSTAT) {
1458:     Vec xx1;

1460:     PetscCall(VecDuplicate(bb, &xx1));
1461:     PetscUseTypeMethod(mat->A, sor, bb, omega, (MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_BACKWARD_SWEEP), fshift, lits, 1, xx);

1463:     PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1464:     PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1465:     if (!mat->diag) {
1466:       PetscCall(MatCreateVecs(matin, &mat->diag, NULL));
1467:       PetscCall(MatGetDiagonal(matin, mat->diag));
1468:     }
1469:     PetscCall(MatHasOperation(matin, MATOP_MULT_DIAGONAL_BLOCK, &hasop));
1470:     if (hasop) PetscCall(MatMultDiagonalBlock(matin, xx, bb1));
1471:     else PetscCall(VecPointwiseMult(bb1, mat->diag, xx));
1472:     PetscCall(VecAYPX(bb1, (omega - 2.0) / omega, bb));

1474:     PetscCall(MatMultAdd(mat->B, mat->lvec, bb1, bb1));

1476:     /* local sweep */
1477:     PetscUseTypeMethod(mat->A, sor, bb1, omega, (MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_FORWARD_SWEEP), fshift, lits, 1, xx1);
1478:     PetscCall(VecAXPY(xx, 1.0, xx1));
1479:     PetscCall(VecDestroy(&xx1));
1480:   } else SETERRQ(PetscObjectComm((PetscObject)matin), PETSC_ERR_SUP, "Parallel SOR not supported");

1482:   PetscCall(VecDestroy(&bb1));

1484:   matin->factorerrortype = mat->A->factorerrortype;
1485:   PetscFunctionReturn(PETSC_SUCCESS);
1486: }

1488: static PetscErrorCode MatPermute_MPIAIJ(Mat A, IS rowp, IS colp, Mat *B)
1489: {
1490:   Mat             aA, aB, Aperm;
1491:   const PetscInt *rwant, *cwant, *gcols, *ai, *bi, *aj, *bj;
1492:   PetscScalar    *aa, *ba;
1493:   PetscInt        i, j, m, n, ng, anz, bnz, *dnnz, *onnz, *tdnnz, *tonnz, *rdest, *cdest, *work, *gcdest;
1494:   PetscSF         rowsf, sf;
1495:   IS              parcolp = NULL;
1496:   PetscBool       done;

1498:   PetscFunctionBegin;
1499:   PetscCall(MatGetLocalSize(A, &m, &n));
1500:   PetscCall(ISGetIndices(rowp, &rwant));
1501:   PetscCall(ISGetIndices(colp, &cwant));
1502:   PetscCall(PetscMalloc3(PetscMax(m, n), &work, m, &rdest, n, &cdest));

1504:   /* Invert row permutation to find out where my rows should go */
1505:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &rowsf));
1506:   PetscCall(PetscSFSetGraphLayout(rowsf, A->rmap, A->rmap->n, NULL, PETSC_OWN_POINTER, rwant));
1507:   PetscCall(PetscSFSetFromOptions(rowsf));
1508:   for (i = 0; i < m; i++) work[i] = A->rmap->rstart + i;
1509:   PetscCall(PetscSFReduceBegin(rowsf, MPIU_INT, work, rdest, MPI_REPLACE));
1510:   PetscCall(PetscSFReduceEnd(rowsf, MPIU_INT, work, rdest, MPI_REPLACE));

1512:   /* Invert column permutation to find out where my columns should go */
1513:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1514:   PetscCall(PetscSFSetGraphLayout(sf, A->cmap, A->cmap->n, NULL, PETSC_OWN_POINTER, cwant));
1515:   PetscCall(PetscSFSetFromOptions(sf));
1516:   for (i = 0; i < n; i++) work[i] = A->cmap->rstart + i;
1517:   PetscCall(PetscSFReduceBegin(sf, MPIU_INT, work, cdest, MPI_REPLACE));
1518:   PetscCall(PetscSFReduceEnd(sf, MPIU_INT, work, cdest, MPI_REPLACE));
1519:   PetscCall(PetscSFDestroy(&sf));

1521:   PetscCall(ISRestoreIndices(rowp, &rwant));
1522:   PetscCall(ISRestoreIndices(colp, &cwant));
1523:   PetscCall(MatMPIAIJGetSeqAIJ(A, &aA, &aB, &gcols));

1525:   /* Find out where my gcols should go */
1526:   PetscCall(MatGetSize(aB, NULL, &ng));
1527:   PetscCall(PetscMalloc1(ng, &gcdest));
1528:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1529:   PetscCall(PetscSFSetGraphLayout(sf, A->cmap, ng, NULL, PETSC_OWN_POINTER, gcols));
1530:   PetscCall(PetscSFSetFromOptions(sf));
1531:   PetscCall(PetscSFBcastBegin(sf, MPIU_INT, cdest, gcdest, MPI_REPLACE));
1532:   PetscCall(PetscSFBcastEnd(sf, MPIU_INT, cdest, gcdest, MPI_REPLACE));
1533:   PetscCall(PetscSFDestroy(&sf));

1535:   PetscCall(PetscCalloc4(m, &dnnz, m, &onnz, m, &tdnnz, m, &tonnz));
1536:   PetscCall(MatGetRowIJ(aA, 0, PETSC_FALSE, PETSC_FALSE, &anz, &ai, &aj, &done));
1537:   PetscCall(MatGetRowIJ(aB, 0, PETSC_FALSE, PETSC_FALSE, &bnz, &bi, &bj, &done));
1538:   for (i = 0; i < m; i++) {
1539:     PetscInt    row = rdest[i];
1540:     PetscMPIInt rowner;
1541:     PetscCall(PetscLayoutFindOwner(A->rmap, row, &rowner));
1542:     for (j = ai[i]; j < ai[i + 1]; j++) {
1543:       PetscInt    col = cdest[aj[j]];
1544:       PetscMPIInt cowner;
1545:       PetscCall(PetscLayoutFindOwner(A->cmap, col, &cowner)); /* Could build an index for the columns to eliminate this search */
1546:       if (rowner == cowner) dnnz[i]++;
1547:       else onnz[i]++;
1548:     }
1549:     for (j = bi[i]; j < bi[i + 1]; j++) {
1550:       PetscInt    col = gcdest[bj[j]];
1551:       PetscMPIInt cowner;
1552:       PetscCall(PetscLayoutFindOwner(A->cmap, col, &cowner));
1553:       if (rowner == cowner) dnnz[i]++;
1554:       else onnz[i]++;
1555:     }
1556:   }
1557:   PetscCall(PetscSFBcastBegin(rowsf, MPIU_INT, dnnz, tdnnz, MPI_REPLACE));
1558:   PetscCall(PetscSFBcastEnd(rowsf, MPIU_INT, dnnz, tdnnz, MPI_REPLACE));
1559:   PetscCall(PetscSFBcastBegin(rowsf, MPIU_INT, onnz, tonnz, MPI_REPLACE));
1560:   PetscCall(PetscSFBcastEnd(rowsf, MPIU_INT, onnz, tonnz, MPI_REPLACE));
1561:   PetscCall(PetscSFDestroy(&rowsf));

1563:   PetscCall(MatCreateAIJ(PetscObjectComm((PetscObject)A), A->rmap->n, A->cmap->n, A->rmap->N, A->cmap->N, 0, tdnnz, 0, tonnz, &Aperm));
1564:   PetscCall(MatSeqAIJGetArray(aA, &aa));
1565:   PetscCall(MatSeqAIJGetArray(aB, &ba));
1566:   for (i = 0; i < m; i++) {
1567:     PetscInt *acols = dnnz, *bcols = onnz; /* Repurpose now-unneeded arrays */
1568:     PetscInt  rowlen;
1569:     rowlen = ai[i + 1] - ai[i];
1570:     for (PetscInt j0 = j = 0; j < rowlen; j0 = j) { /* rowlen could be larger than number of rows m, so sum in batches */
1571:       for (; j < PetscMin(rowlen, j0 + m); j++) acols[j - j0] = cdest[aj[ai[i] + j]];
1572:       PetscCall(MatSetValues(Aperm, 1, &rdest[i], j - j0, acols, aa + ai[i] + j0, INSERT_VALUES));
1573:     }
1574:     rowlen = bi[i + 1] - bi[i];
1575:     for (PetscInt j0 = j = 0; j < rowlen; j0 = j) {
1576:       for (; j < PetscMin(rowlen, j0 + m); j++) bcols[j - j0] = gcdest[bj[bi[i] + j]];
1577:       PetscCall(MatSetValues(Aperm, 1, &rdest[i], j - j0, bcols, ba + bi[i] + j0, INSERT_VALUES));
1578:     }
1579:   }
1580:   PetscCall(MatAssemblyBegin(Aperm, MAT_FINAL_ASSEMBLY));
1581:   PetscCall(MatAssemblyEnd(Aperm, MAT_FINAL_ASSEMBLY));
1582:   PetscCall(MatRestoreRowIJ(aA, 0, PETSC_FALSE, PETSC_FALSE, &anz, &ai, &aj, &done));
1583:   PetscCall(MatRestoreRowIJ(aB, 0, PETSC_FALSE, PETSC_FALSE, &bnz, &bi, &bj, &done));
1584:   PetscCall(MatSeqAIJRestoreArray(aA, &aa));
1585:   PetscCall(MatSeqAIJRestoreArray(aB, &ba));
1586:   PetscCall(PetscFree4(dnnz, onnz, tdnnz, tonnz));
1587:   PetscCall(PetscFree3(work, rdest, cdest));
1588:   PetscCall(PetscFree(gcdest));
1589:   if (parcolp) PetscCall(ISDestroy(&colp));
1590:   *B = Aperm;
1591:   PetscFunctionReturn(PETSC_SUCCESS);
1592: }

1594: static PetscErrorCode MatGetGhosts_MPIAIJ(Mat mat, PetscInt *nghosts, const PetscInt *ghosts[])
1595: {
1596:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

1598:   PetscFunctionBegin;
1599:   PetscCall(MatGetSize(aij->B, NULL, nghosts));
1600:   if (ghosts) *ghosts = aij->garray;
1601:   PetscFunctionReturn(PETSC_SUCCESS);
1602: }

1604: static PetscErrorCode MatGetInfo_MPIAIJ(Mat matin, MatInfoType flag, MatInfo *info)
1605: {
1606:   Mat_MPIAIJ    *mat = (Mat_MPIAIJ *)matin->data;
1607:   Mat            A = mat->A, B = mat->B;
1608:   PetscLogDouble irecv[5];

1610:   PetscFunctionBegin;
1611:   info->block_size = 1.0;
1612:   PetscCall(MatGetInfo(A, MAT_LOCAL, info));

1614:   irecv[0] = info->nz_used;
1615:   irecv[1] = info->nz_allocated;
1616:   irecv[2] = info->nz_unneeded;
1617:   irecv[3] = info->memory;
1618:   irecv[4] = info->mallocs;

1620:   PetscCall(MatGetInfo(B, MAT_LOCAL, info));

1622:   irecv[0] += info->nz_used;
1623:   irecv[1] += info->nz_allocated;
1624:   irecv[2] += info->nz_unneeded;
1625:   irecv[3] += info->memory;
1626:   irecv[4] += info->mallocs;
1627:   if (flag == MAT_LOCAL) {
1628:     info->nz_used      = irecv[0];
1629:     info->nz_allocated = irecv[1];
1630:     info->nz_unneeded  = irecv[2];
1631:     info->memory       = irecv[3];
1632:     info->mallocs      = irecv[4];
1633:   } else if (flag == MAT_GLOBAL_MAX) {
1634:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, irecv, 5, MPIU_PETSCLOGDOUBLE, MPI_MAX, PetscObjectComm((PetscObject)matin)));

1636:     info->nz_used      = irecv[0];
1637:     info->nz_allocated = irecv[1];
1638:     info->nz_unneeded  = irecv[2];
1639:     info->memory       = irecv[3];
1640:     info->mallocs      = irecv[4];
1641:   } else if (flag == MAT_GLOBAL_SUM) {
1642:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, irecv, 5, MPIU_PETSCLOGDOUBLE, MPI_SUM, PetscObjectComm((PetscObject)matin)));

1644:     info->nz_used      = irecv[0];
1645:     info->nz_allocated = irecv[1];
1646:     info->nz_unneeded  = irecv[2];
1647:     info->memory       = irecv[3];
1648:     info->mallocs      = irecv[4];
1649:   }
1650:   info->fill_ratio_given  = 0; /* no parallel LU/ILU/Cholesky */
1651:   info->fill_ratio_needed = 0;
1652:   info->factor_mallocs    = 0;
1653:   PetscFunctionReturn(PETSC_SUCCESS);
1654: }

1656: PetscErrorCode MatSetOption_MPIAIJ(Mat A, MatOption op, PetscBool flg)
1657: {
1658:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1660:   PetscFunctionBegin;
1661:   switch (op) {
1662:   case MAT_NEW_NONZERO_LOCATIONS:
1663:   case MAT_NEW_NONZERO_ALLOCATION_ERR:
1664:   case MAT_UNUSED_NONZERO_LOCATION_ERR:
1665:   case MAT_KEEP_NONZERO_PATTERN:
1666:   case MAT_NEW_NONZERO_LOCATION_ERR:
1667:   case MAT_USE_INODES:
1668:   case MAT_IGNORE_ZERO_ENTRIES:
1669:   case MAT_FORM_EXPLICIT_TRANSPOSE:
1670:     MatCheckPreallocated(A, 1);
1671:     PetscCall(MatSetOption(a->A, op, flg));
1672:     PetscCall(MatSetOption(a->B, op, flg));
1673:     break;
1674:   case MAT_ROW_ORIENTED:
1675:     MatCheckPreallocated(A, 1);
1676:     a->roworiented = flg;

1678:     PetscCall(MatSetOption(a->A, op, flg));
1679:     PetscCall(MatSetOption(a->B, op, flg));
1680:     break;
1681:   case MAT_IGNORE_OFF_PROC_ENTRIES:
1682:     a->donotstash = flg;
1683:     break;
1684:   /* Symmetry flags are handled directly by MatSetOption() and they don't affect preallocation */
1685:   case MAT_SPD:
1686:   case MAT_SYMMETRIC:
1687:   case MAT_STRUCTURALLY_SYMMETRIC:
1688:   case MAT_HERMITIAN:
1689:   case MAT_SYMMETRY_ETERNAL:
1690:   case MAT_STRUCTURAL_SYMMETRY_ETERNAL:
1691:   case MAT_SPD_ETERNAL:
1692:     /* if the diagonal matrix is square it inherits some of the properties above */
1693:     if (a->A && A->rmap->n == A->cmap->n) PetscCall(MatSetOption(a->A, op, flg));
1694:     break;
1695:   case MAT_SUBMAT_SINGLEIS:
1696:     A->submat_singleis = flg;
1697:     break;
1698:   default:
1699:     break;
1700:   }
1701:   PetscFunctionReturn(PETSC_SUCCESS);
1702: }

1704: PetscErrorCode MatGetRow_MPIAIJ(Mat matin, PetscInt row, PetscInt *nz, PetscInt **idx, PetscScalar **v)
1705: {
1706:   Mat_MPIAIJ  *mat = (Mat_MPIAIJ *)matin->data;
1707:   PetscScalar *vworkA, *vworkB, **pvA, **pvB, *v_p;
1708:   PetscInt     i, *cworkA, *cworkB, **pcA, **pcB, cstart = matin->cmap->rstart;
1709:   PetscInt     nztot, nzA, nzB, lrow, rstart = matin->rmap->rstart, rend = matin->rmap->rend;
1710:   PetscInt    *cmap, *idx_p;

1712:   PetscFunctionBegin;
1713:   PetscCheck(!mat->getrowactive, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Already active");
1714:   mat->getrowactive = PETSC_TRUE;

1716:   if (!mat->rowvalues && (idx || v)) {
1717:     /*
1718:         allocate enough space to hold information from the longest row.
1719:     */
1720:     Mat_SeqAIJ *Aa = (Mat_SeqAIJ *)mat->A->data, *Ba = (Mat_SeqAIJ *)mat->B->data;
1721:     PetscInt    max = 1, tmp;
1722:     for (i = 0; i < matin->rmap->n; i++) {
1723:       tmp = Aa->i[i + 1] - Aa->i[i] + Ba->i[i + 1] - Ba->i[i];
1724:       if (max < tmp) max = tmp;
1725:     }
1726:     PetscCall(PetscMalloc2(max, &mat->rowvalues, max, &mat->rowindices));
1727:   }

1729:   PetscCheck(row >= rstart && row < rend, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Only local rows");
1730:   lrow = row - rstart;

1732:   pvA = &vworkA;
1733:   pcA = &cworkA;
1734:   pvB = &vworkB;
1735:   pcB = &cworkB;
1736:   if (!v) {
1737:     pvA = NULL;
1738:     pvB = NULL;
1739:   }
1740:   if (!idx) {
1741:     pcA = NULL;
1742:     if (!v) pcB = NULL;
1743:   }
1744:   PetscUseTypeMethod(mat->A, getrow, lrow, &nzA, pcA, pvA);
1745:   PetscUseTypeMethod(mat->B, getrow, lrow, &nzB, pcB, pvB);
1746:   nztot = nzA + nzB;

1748:   cmap = mat->garray;
1749:   if (v || idx) {
1750:     if (nztot) {
1751:       /* Sort by increasing column numbers, assuming A and B already sorted */
1752:       PetscInt imark = -1;
1753:       if (v) {
1754:         *v = v_p = mat->rowvalues;
1755:         for (i = 0; i < nzB; i++) {
1756:           if (cmap[cworkB[i]] < cstart) v_p[i] = vworkB[i];
1757:           else break;
1758:         }
1759:         imark = i;
1760:         for (i = 0; i < nzA; i++) v_p[imark + i] = vworkA[i];
1761:         for (i = imark; i < nzB; i++) v_p[nzA + i] = vworkB[i];
1762:       }
1763:       if (idx) {
1764:         *idx = idx_p = mat->rowindices;
1765:         if (imark > -1) {
1766:           for (i = 0; i < imark; i++) idx_p[i] = cmap[cworkB[i]];
1767:         } else {
1768:           for (i = 0; i < nzB; i++) {
1769:             if (cmap[cworkB[i]] < cstart) idx_p[i] = cmap[cworkB[i]];
1770:             else break;
1771:           }
1772:           imark = i;
1773:         }
1774:         for (i = 0; i < nzA; i++) idx_p[imark + i] = cstart + cworkA[i];
1775:         for (i = imark; i < nzB; i++) idx_p[nzA + i] = cmap[cworkB[i]];
1776:       }
1777:     } else {
1778:       if (idx) *idx = NULL;
1779:       if (v) *v = NULL;
1780:     }
1781:   }
1782:   *nz = nztot;
1783:   PetscUseTypeMethod(mat->A, restorerow, lrow, &nzA, pcA, pvA);
1784:   PetscUseTypeMethod(mat->B, restorerow, lrow, &nzB, pcB, pvB);
1785:   PetscFunctionReturn(PETSC_SUCCESS);
1786: }

1788: PetscErrorCode MatRestoreRow_MPIAIJ(Mat mat, PetscInt row, PetscInt *nz, PetscInt **idx, PetscScalar **v)
1789: {
1790:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

1792:   PetscFunctionBegin;
1793:   PetscCheck(aij->getrowactive, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "MatGetRow() must be called first");
1794:   aij->getrowactive = PETSC_FALSE;
1795:   PetscFunctionReturn(PETSC_SUCCESS);
1796: }

1798: static PetscErrorCode MatNorm_MPIAIJ(Mat mat, NormType type, PetscReal *norm)
1799: {
1800:   Mat_MPIAIJ      *aij  = (Mat_MPIAIJ *)mat->data;
1801:   Mat_SeqAIJ      *amat = (Mat_SeqAIJ *)aij->A->data, *bmat = (Mat_SeqAIJ *)aij->B->data;
1802:   PetscInt         i, j;
1803:   PetscReal        sum = 0.0;
1804:   const MatScalar *v, *amata, *bmata;

1806:   PetscFunctionBegin;
1807:   if (aij->size == 1) {
1808:     PetscCall(MatNorm(aij->A, type, norm));
1809:   } else {
1810:     PetscCall(MatSeqAIJGetArrayRead(aij->A, &amata));
1811:     PetscCall(MatSeqAIJGetArrayRead(aij->B, &bmata));
1812:     if (type == NORM_FROBENIUS) {
1813:       v = amata;
1814:       for (i = 0; i < amat->nz; i++) {
1815:         sum += PetscRealPart(PetscConj(*v) * (*v));
1816:         v++;
1817:       }
1818:       v = bmata;
1819:       for (i = 0; i < bmat->nz; i++) {
1820:         sum += PetscRealPart(PetscConj(*v) * (*v));
1821:         v++;
1822:       }
1823:       PetscCallMPI(MPIU_Allreduce(&sum, norm, 1, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)mat)));
1824:       *norm = PetscSqrtReal(*norm);
1825:       PetscCall(PetscLogFlops(2.0 * amat->nz + 2.0 * bmat->nz));
1826:     } else if (type == NORM_1) { /* max column norm */
1827:       Vec          col, bcol;
1828:       PetscScalar *array;
1829:       PetscInt    *jj, *garray = aij->garray;

1831:       PetscCall(MatCreateVecs(mat, &col, NULL));
1832:       PetscCall(VecGetArrayWrite(col, &array));
1833:       v  = amata;
1834:       jj = amat->j;
1835:       for (j = 0; j < amat->nz; j++) array[*jj++] += PetscAbsScalar(*v++);
1836:       PetscCall(VecRestoreArrayWrite(col, &array));
1837:       PetscCall(MatCreateVecs(aij->B, &bcol, NULL));
1838:       PetscCall(VecGetArrayWrite(bcol, &array));
1839:       v  = bmata;
1840:       jj = bmat->j;
1841:       for (j = 0; j < bmat->nz; j++) array[*jj++] += PetscAbsScalar(*v++);
1842:       PetscCall(VecSetValues(col, aij->B->cmap->n, garray, array, ADD_VALUES));
1843:       PetscCall(VecRestoreArrayWrite(bcol, &array));
1844:       PetscCall(VecDestroy(&bcol));
1845:       PetscCall(VecAssemblyBegin(col));
1846:       PetscCall(VecAssemblyEnd(col));
1847:       PetscCall(VecNorm(col, NORM_INFINITY, norm));
1848:       PetscCall(VecDestroy(&col));
1849:     } else if (type == NORM_INFINITY) { /* max row norm */
1850:       *norm = 0.0;
1851:       for (j = 0; j < aij->A->rmap->n; j++) {
1852:         v   = PetscSafePointerPlusOffset(amata, amat->i[j]);
1853:         sum = 0.0;
1854:         for (i = 0; i < amat->i[j + 1] - amat->i[j]; i++) {
1855:           sum += PetscAbsScalar(*v);
1856:           v++;
1857:         }
1858:         v = PetscSafePointerPlusOffset(bmata, bmat->i[j]);
1859:         for (i = 0; i < bmat->i[j + 1] - bmat->i[j]; i++) {
1860:           sum += PetscAbsScalar(*v);
1861:           v++;
1862:         }
1863:         if (sum > *norm) *norm = sum;
1864:       }
1865:       PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, norm, 1, MPIU_REAL, MPIU_MAX, PetscObjectComm((PetscObject)mat)));
1866:       PetscCall(PetscLogFlops(PetscMax(amat->nz + bmat->nz - 1, 0)));
1867:     } else SETERRQ(PetscObjectComm((PetscObject)mat), PETSC_ERR_SUP, "No support for two norm");
1868:     PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &amata));
1869:     PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &bmata));
1870:   }
1871:   PetscFunctionReturn(PETSC_SUCCESS);
1872: }

1874: static PetscErrorCode MatTranspose_MPIAIJ(Mat A, MatReuse reuse, Mat *matout)
1875: {
1876:   Mat_MPIAIJ      *a    = (Mat_MPIAIJ *)A->data, *b;
1877:   Mat_SeqAIJ      *Aloc = (Mat_SeqAIJ *)a->A->data, *Bloc = (Mat_SeqAIJ *)a->B->data, *sub_B_diag;
1878:   PetscInt         M = A->rmap->N, N = A->cmap->N, ma, na, mb, nb, row, *cols, *cols_tmp, *B_diag_ilen, i, ncol, A_diag_ncol;
1879:   const PetscInt  *ai, *aj, *bi, *bj, *B_diag_i;
1880:   Mat              B, A_diag, *B_diag;
1881:   const MatScalar *pbv, *bv;

1883:   PetscFunctionBegin;
1884:   if (reuse == MAT_REUSE_MATRIX) PetscCall(MatTransposeCheckNonzeroState_Private(A, *matout));
1885:   ma = A->rmap->n;
1886:   na = A->cmap->n;
1887:   mb = a->B->rmap->n;
1888:   nb = a->B->cmap->n;
1889:   ai = Aloc->i;
1890:   aj = Aloc->j;
1891:   bi = Bloc->i;
1892:   bj = Bloc->j;
1893:   if (reuse == MAT_INITIAL_MATRIX || *matout == A) {
1894:     PetscInt            *d_nnz, *g_nnz, *o_nnz;
1895:     PetscSFNode         *oloc;
1896:     PETSC_UNUSED PetscSF sf;

1898:     PetscCall(PetscMalloc4(na, &d_nnz, na, &o_nnz, nb, &g_nnz, nb, &oloc));
1899:     /* compute d_nnz for preallocation */
1900:     PetscCall(PetscArrayzero(d_nnz, na));
1901:     for (i = 0; i < ai[ma]; i++) d_nnz[aj[i]]++;
1902:     /* compute local off-diagonal contributions */
1903:     PetscCall(PetscArrayzero(g_nnz, nb));
1904:     for (i = 0; i < bi[ma]; i++) g_nnz[bj[i]]++;
1905:     /* map those to global */
1906:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1907:     PetscCall(PetscSFSetGraphLayout(sf, A->cmap, nb, NULL, PETSC_USE_POINTER, a->garray));
1908:     PetscCall(PetscSFSetFromOptions(sf));
1909:     PetscCall(PetscArrayzero(o_nnz, na));
1910:     PetscCall(PetscSFReduceBegin(sf, MPIU_INT, g_nnz, o_nnz, MPI_SUM));
1911:     PetscCall(PetscSFReduceEnd(sf, MPIU_INT, g_nnz, o_nnz, MPI_SUM));
1912:     PetscCall(PetscSFDestroy(&sf));

1914:     PetscCall(MatCreate(PetscObjectComm((PetscObject)A), &B));
1915:     PetscCall(MatSetSizes(B, A->cmap->n, A->rmap->n, N, M));
1916:     PetscCall(MatSetBlockSizes(B, A->cmap->bs, A->rmap->bs));
1917:     PetscCall(MatSetType(B, ((PetscObject)A)->type_name));
1918:     PetscCall(MatMPIAIJSetPreallocation(B, 0, d_nnz, 0, o_nnz));
1919:     PetscCall(PetscFree4(d_nnz, o_nnz, g_nnz, oloc));
1920:   } else {
1921:     B = *matout;
1922:     PetscCall(MatSetOption(B, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_TRUE));
1923:   }

1925:   b           = (Mat_MPIAIJ *)B->data;
1926:   A_diag      = a->A;
1927:   B_diag      = &b->A;
1928:   sub_B_diag  = (Mat_SeqAIJ *)(*B_diag)->data;
1929:   A_diag_ncol = A_diag->cmap->N;
1930:   B_diag_ilen = sub_B_diag->ilen;
1931:   B_diag_i    = sub_B_diag->i;

1933:   /* Set ilen for diagonal of B */
1934:   for (i = 0; i < A_diag_ncol; i++) B_diag_ilen[i] = B_diag_i[i + 1] - B_diag_i[i];

1936:   /* Transpose the diagonal part of the matrix. In contrast to the off-diagonal part, this can be done
1937:   very quickly (=without using MatSetValues), because all writes are local. */
1938:   PetscCall(MatTransposeSetPrecursor(A_diag, *B_diag));
1939:   PetscCall(MatTranspose(A_diag, MAT_REUSE_MATRIX, B_diag));

1941:   /* copy over the B part */
1942:   PetscCall(PetscMalloc1(bi[mb], &cols));
1943:   PetscCall(MatSeqAIJGetArrayRead(a->B, &bv));
1944:   pbv = bv;
1945:   row = A->rmap->rstart;
1946:   for (i = 0; i < bi[mb]; i++) cols[i] = a->garray[bj[i]];
1947:   cols_tmp = cols;
1948:   for (i = 0; i < mb; i++) {
1949:     ncol = bi[i + 1] - bi[i];
1950:     PetscCall(MatSetValues(B, ncol, cols_tmp, 1, &row, pbv, INSERT_VALUES));
1951:     row++;
1952:     if (pbv) pbv += ncol;
1953:     if (cols_tmp) cols_tmp += ncol;
1954:   }
1955:   PetscCall(PetscFree(cols));
1956:   PetscCall(MatSeqAIJRestoreArrayRead(a->B, &bv));

1958:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
1959:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
1960:   if (reuse == MAT_INITIAL_MATRIX || reuse == MAT_REUSE_MATRIX) {
1961:     *matout = B;
1962:   } else {
1963:     PetscCall(MatHeaderMerge(A, &B));
1964:   }
1965:   PetscFunctionReturn(PETSC_SUCCESS);
1966: }

1968: static PetscErrorCode MatDiagonalScale_MPIAIJ(Mat mat, Vec ll, Vec rr)
1969: {
1970:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
1971:   Mat         a = aij->A, b = aij->B;
1972:   PetscInt    s1, s2, s3;

1974:   PetscFunctionBegin;
1975:   PetscCall(MatGetLocalSize(mat, &s2, &s3));
1976:   if (rr) {
1977:     PetscCall(VecGetLocalSize(rr, &s1));
1978:     PetscCheck(s1 == s3, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "right vector non-conforming local size");
1979:     /* Overlap communication with computation. */
1980:     PetscCall(VecScatterBegin(aij->Mvctx, rr, aij->lvec, INSERT_VALUES, SCATTER_FORWARD));
1981:   }
1982:   if (ll) {
1983:     PetscCall(VecGetLocalSize(ll, &s1));
1984:     PetscCheck(s1 == s2, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "left vector non-conforming local size");
1985:     PetscUseTypeMethod(b, diagonalscale, ll, NULL);
1986:   }
1987:   /* scale  the diagonal block */
1988:   PetscUseTypeMethod(a, diagonalscale, ll, rr);

1990:   if (rr) {
1991:     /* Do a scatter end and then right scale the off-diagonal block */
1992:     PetscCall(VecScatterEnd(aij->Mvctx, rr, aij->lvec, INSERT_VALUES, SCATTER_FORWARD));
1993:     PetscUseTypeMethod(b, diagonalscale, NULL, aij->lvec);
1994:   }
1995:   PetscFunctionReturn(PETSC_SUCCESS);
1996: }

1998: static PetscErrorCode MatSetUnfactored_MPIAIJ(Mat A)
1999: {
2000:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2002:   PetscFunctionBegin;
2003:   PetscCall(MatSetUnfactored(a->A));
2004:   PetscFunctionReturn(PETSC_SUCCESS);
2005: }

2007: static PetscErrorCode MatEqual_MPIAIJ(Mat A, Mat B, PetscBool *flag)
2008: {
2009:   Mat_MPIAIJ *matB = (Mat_MPIAIJ *)B->data, *matA = (Mat_MPIAIJ *)A->data;
2010:   Mat         a, b, c, d;

2012:   PetscFunctionBegin;
2013:   a = matA->A;
2014:   b = matA->B;
2015:   c = matB->A;
2016:   d = matB->B;

2018:   PetscCall(MatEqual(a, c, flag));
2019:   if (*flag) PetscCall(MatEqual(b, d, flag));
2020:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, flag, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)A)));
2021:   PetscFunctionReturn(PETSC_SUCCESS);
2022: }

2024: static PetscErrorCode MatCopy_MPIAIJ(Mat A, Mat B, MatStructure str)
2025: {
2026:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
2027:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;

2029:   PetscFunctionBegin;
2030:   /* If the two matrices don't have the same copy implementation, they aren't compatible for fast copy. */
2031:   if ((str != SAME_NONZERO_PATTERN) || (A->ops->copy != B->ops->copy)) {
2032:     /* because of the column compression in the off-processor part of the matrix a->B,
2033:        the number of columns in a->B and b->B may be different, hence we cannot call
2034:        the MatCopy() directly on the two parts. If need be, we can provide a more
2035:        efficient copy than the MatCopy_Basic() by first uncompressing the a->B matrices
2036:        then copying the submatrices */
2037:     PetscCall(MatCopy_Basic(A, B, str));
2038:   } else {
2039:     PetscCall(MatCopy(a->A, b->A, str));
2040:     PetscCall(MatCopy(a->B, b->B, str));
2041:   }
2042:   PetscCall(PetscObjectStateIncrease((PetscObject)B));
2043:   PetscFunctionReturn(PETSC_SUCCESS);
2044: }

2046: /*
2047:    Computes the number of nonzeros per row needed for preallocation when X and Y
2048:    have different nonzero structure.
2049: */
2050: PetscErrorCode MatAXPYGetPreallocation_MPIX_private(PetscInt m, const PetscInt *xi, const PetscInt *xj, const PetscInt *xltog, const PetscInt *yi, const PetscInt *yj, const PetscInt *yltog, PetscInt *nnz)
2051: {
2052:   PetscInt i, j, k, nzx, nzy;

2054:   PetscFunctionBegin;
2055:   /* Set the number of nonzeros in the new matrix */
2056:   for (i = 0; i < m; i++) {
2057:     const PetscInt *xjj = PetscSafePointerPlusOffset(xj, xi[i]), *yjj = PetscSafePointerPlusOffset(yj, yi[i]);
2058:     nzx    = xi[i + 1] - xi[i];
2059:     nzy    = yi[i + 1] - yi[i];
2060:     nnz[i] = 0;
2061:     for (j = 0, k = 0; j < nzx; j++) {                                /* Point in X */
2062:       for (; k < nzy && yltog[yjj[k]] < xltog[xjj[j]]; k++) nnz[i]++; /* Catch up to X */
2063:       if (k < nzy && yltog[yjj[k]] == xltog[xjj[j]]) k++;             /* Skip duplicate */
2064:       nnz[i]++;
2065:     }
2066:     for (; k < nzy; k++) nnz[i]++;
2067:   }
2068:   PetscFunctionReturn(PETSC_SUCCESS);
2069: }

2071: /* This is the same as MatAXPYGetPreallocation_SeqAIJ, except that the local-to-global map is provided */
2072: static PetscErrorCode MatAXPYGetPreallocation_MPIAIJ(Mat Y, const PetscInt *yltog, Mat X, const PetscInt *xltog, PetscInt *nnz)
2073: {
2074:   PetscInt    m = Y->rmap->N;
2075:   Mat_SeqAIJ *x = (Mat_SeqAIJ *)X->data;
2076:   Mat_SeqAIJ *y = (Mat_SeqAIJ *)Y->data;

2078:   PetscFunctionBegin;
2079:   PetscCall(MatAXPYGetPreallocation_MPIX_private(m, x->i, x->j, xltog, y->i, y->j, yltog, nnz));
2080:   PetscFunctionReturn(PETSC_SUCCESS);
2081: }

2083: static PetscErrorCode MatAXPY_MPIAIJ(Mat Y, PetscScalar a, Mat X, MatStructure str)
2084: {
2085:   Mat_MPIAIJ *xx = (Mat_MPIAIJ *)X->data, *yy = (Mat_MPIAIJ *)Y->data;

2087:   PetscFunctionBegin;
2088:   if (str == SAME_NONZERO_PATTERN) {
2089:     PetscCall(MatAXPY(yy->A, a, xx->A, str));
2090:     PetscCall(MatAXPY(yy->B, a, xx->B, str));
2091:   } else if (str == SUBSET_NONZERO_PATTERN) { /* nonzeros of X is a subset of Y's */
2092:     PetscCall(MatAXPY_Basic(Y, a, X, str));
2093:   } else {
2094:     Mat       B;
2095:     PetscInt *nnz_d, *nnz_o;

2097:     PetscCall(PetscMalloc1(yy->A->rmap->N, &nnz_d));
2098:     PetscCall(PetscMalloc1(yy->B->rmap->N, &nnz_o));
2099:     PetscCall(MatCreate(PetscObjectComm((PetscObject)Y), &B));
2100:     PetscCall(PetscObjectSetName((PetscObject)B, ((PetscObject)Y)->name));
2101:     PetscCall(MatSetLayouts(B, Y->rmap, Y->cmap));
2102:     PetscCall(MatSetType(B, ((PetscObject)Y)->type_name));
2103:     PetscCall(MatAXPYGetPreallocation_SeqAIJ(yy->A, xx->A, nnz_d));
2104:     PetscCall(MatAXPYGetPreallocation_MPIAIJ(yy->B, yy->garray, xx->B, xx->garray, nnz_o));
2105:     PetscCall(MatMPIAIJSetPreallocation(B, 0, nnz_d, 0, nnz_o));
2106:     PetscCall(MatAXPY_BasicWithPreallocation(B, Y, a, X, str));
2107:     PetscCall(MatHeaderMerge(Y, &B));
2108:     PetscCall(PetscFree(nnz_d));
2109:     PetscCall(PetscFree(nnz_o));
2110:   }
2111:   PetscFunctionReturn(PETSC_SUCCESS);
2112: }

2114: PETSC_INTERN PetscErrorCode MatConjugate_SeqAIJ(Mat);

2116: static PetscErrorCode MatConjugate_MPIAIJ(Mat mat)
2117: {
2118:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2120:   PetscFunctionBegin;
2121:   PetscCall(MatConjugate_SeqAIJ(aij->A));
2122:   PetscCall(MatConjugate_SeqAIJ(aij->B));
2123:   PetscFunctionReturn(PETSC_SUCCESS);
2124: }

2126: static PetscErrorCode MatRealPart_MPIAIJ(Mat A)
2127: {
2128:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2130:   PetscFunctionBegin;
2131:   PetscCall(MatRealPart(a->A));
2132:   PetscCall(MatRealPart(a->B));
2133:   PetscFunctionReturn(PETSC_SUCCESS);
2134: }

2136: static PetscErrorCode MatImaginaryPart_MPIAIJ(Mat A)
2137: {
2138:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2140:   PetscFunctionBegin;
2141:   PetscCall(MatImaginaryPart(a->A));
2142:   PetscCall(MatImaginaryPart(a->B));
2143:   PetscFunctionReturn(PETSC_SUCCESS);
2144: }

2146: static PetscErrorCode MatGetRowMaxAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2147: {
2148:   Mat_MPIAIJ        *a = (Mat_MPIAIJ *)A->data;
2149:   PetscInt           i, *idxb = NULL, m = A->rmap->n;
2150:   PetscScalar       *vv;
2151:   Vec                vB, vA;
2152:   const PetscScalar *va, *vb;

2154:   PetscFunctionBegin;
2155:   PetscCall(MatCreateVecs(a->A, NULL, &vA));
2156:   PetscCall(MatGetRowMaxAbs(a->A, vA, idx));

2158:   PetscCall(VecGetArrayRead(vA, &va));
2159:   if (idx) {
2160:     for (i = 0; i < m; i++) {
2161:       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
2162:     }
2163:   }

2165:   PetscCall(MatCreateVecs(a->B, NULL, &vB));
2166:   PetscCall(PetscMalloc1(m, &idxb));
2167:   PetscCall(MatGetRowMaxAbs(a->B, vB, idxb));

2169:   PetscCall(VecGetArrayWrite(v, &vv));
2170:   PetscCall(VecGetArrayRead(vB, &vb));
2171:   for (i = 0; i < m; i++) {
2172:     if (PetscAbsScalar(va[i]) < PetscAbsScalar(vb[i])) {
2173:       vv[i] = vb[i];
2174:       if (idx) idx[i] = a->garray[idxb[i]];
2175:     } else {
2176:       vv[i] = va[i];
2177:       if (idx && PetscAbsScalar(va[i]) == PetscAbsScalar(vb[i]) && idxb[i] != -1 && idx[i] > a->garray[idxb[i]]) idx[i] = a->garray[idxb[i]];
2178:     }
2179:   }
2180:   PetscCall(VecRestoreArrayWrite(v, &vv));
2181:   PetscCall(VecRestoreArrayRead(vA, &va));
2182:   PetscCall(VecRestoreArrayRead(vB, &vb));
2183:   PetscCall(PetscFree(idxb));
2184:   PetscCall(VecDestroy(&vA));
2185:   PetscCall(VecDestroy(&vB));
2186:   PetscFunctionReturn(PETSC_SUCCESS);
2187: }

2189: static PetscErrorCode MatGetRowSumAbs_MPIAIJ(Mat A, Vec v)
2190: {
2191:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
2192:   Vec         vB, vA;

2194:   PetscFunctionBegin;
2195:   PetscCall(MatCreateVecs(a->A, NULL, &vA));
2196:   PetscCall(MatGetRowSumAbs(a->A, vA));
2197:   PetscCall(MatCreateVecs(a->B, NULL, &vB));
2198:   PetscCall(MatGetRowSumAbs(a->B, vB));
2199:   PetscCall(VecAXPY(vA, 1.0, vB));
2200:   PetscCall(VecDestroy(&vB));
2201:   PetscCall(VecCopy(vA, v));
2202:   PetscCall(VecDestroy(&vA));
2203:   PetscFunctionReturn(PETSC_SUCCESS);
2204: }

2206: static PetscErrorCode MatGetRowMinAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2207: {
2208:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2209:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2210:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2211:   PetscInt          *cmap = mat->garray;
2212:   PetscInt          *diagIdx, *offdiagIdx;
2213:   Vec                diagV, offdiagV;
2214:   PetscScalar       *a, *diagA, *offdiagA;
2215:   const PetscScalar *ba, *bav;
2216:   PetscInt           r, j, col, ncols, *bi, *bj;
2217:   Mat                B = mat->B;
2218:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2220:   PetscFunctionBegin;
2221:   /* When a process holds entire A and other processes have no entry */
2222:   if (A->cmap->N == n) {
2223:     PetscCall(VecGetArrayWrite(v, &diagA));
2224:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2225:     PetscCall(MatGetRowMinAbs(mat->A, diagV, idx));
2226:     PetscCall(VecDestroy(&diagV));
2227:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2228:     PetscFunctionReturn(PETSC_SUCCESS);
2229:   } else if (n == 0) {
2230:     if (m) {
2231:       PetscCall(VecGetArrayWrite(v, &a));
2232:       for (r = 0; r < m; r++) {
2233:         a[r] = 0.0;
2234:         if (idx) idx[r] = -1;
2235:       }
2236:       PetscCall(VecRestoreArrayWrite(v, &a));
2237:     }
2238:     PetscFunctionReturn(PETSC_SUCCESS);
2239:   }

2241:   PetscCall(PetscMalloc2(m, &diagIdx, m, &offdiagIdx));
2242:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2243:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2244:   PetscCall(MatGetRowMinAbs(mat->A, diagV, diagIdx));

2246:   /* Get offdiagIdx[] for implicit 0.0 */
2247:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2248:   ba = bav;
2249:   bi = b->i;
2250:   bj = b->j;
2251:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2252:   for (r = 0; r < m; r++) {
2253:     ncols = bi[r + 1] - bi[r];
2254:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2255:       offdiagA[r]   = *ba;
2256:       offdiagIdx[r] = cmap[0];
2257:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2258:       offdiagA[r] = 0.0;

2260:       /* Find first hole in the cmap */
2261:       for (j = 0; j < ncols; j++) {
2262:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2263:         if (col > j && j < cstart) {
2264:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2265:           break;
2266:         } else if (col > j + n && j >= cstart) {
2267:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2268:           break;
2269:         }
2270:       }
2271:       if (j == ncols && ncols < A->cmap->N - n) {
2272:         /* a hole is outside compressed Bcols */
2273:         if (ncols == 0) {
2274:           if (cstart) {
2275:             offdiagIdx[r] = 0;
2276:           } else offdiagIdx[r] = cend;
2277:         } else { /* ncols > 0 */
2278:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2279:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2280:         }
2281:       }
2282:     }

2284:     for (j = 0; j < ncols; j++) {
2285:       if (PetscAbsScalar(offdiagA[r]) > PetscAbsScalar(*ba)) {
2286:         offdiagA[r]   = *ba;
2287:         offdiagIdx[r] = cmap[*bj];
2288:       }
2289:       ba++;
2290:       bj++;
2291:     }
2292:   }

2294:   PetscCall(VecGetArrayWrite(v, &a));
2295:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2296:   for (r = 0; r < m; ++r) {
2297:     if (PetscAbsScalar(diagA[r]) < PetscAbsScalar(offdiagA[r])) {
2298:       a[r] = diagA[r];
2299:       if (idx) idx[r] = cstart + diagIdx[r];
2300:     } else if (PetscAbsScalar(diagA[r]) == PetscAbsScalar(offdiagA[r])) {
2301:       a[r] = diagA[r];
2302:       if (idx) {
2303:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2304:           idx[r] = cstart + diagIdx[r];
2305:         } else idx[r] = offdiagIdx[r];
2306:       }
2307:     } else {
2308:       a[r] = offdiagA[r];
2309:       if (idx) idx[r] = offdiagIdx[r];
2310:     }
2311:   }
2312:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2313:   PetscCall(VecRestoreArrayWrite(v, &a));
2314:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2315:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2316:   PetscCall(VecDestroy(&diagV));
2317:   PetscCall(VecDestroy(&offdiagV));
2318:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2319:   PetscFunctionReturn(PETSC_SUCCESS);
2320: }

2322: static PetscErrorCode MatGetRowMin_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2323: {
2324:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2325:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2326:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2327:   PetscInt          *cmap = mat->garray;
2328:   PetscInt          *diagIdx, *offdiagIdx;
2329:   Vec                diagV, offdiagV;
2330:   PetscScalar       *a, *diagA, *offdiagA;
2331:   const PetscScalar *ba, *bav;
2332:   PetscInt           r, j, col, ncols, *bi, *bj;
2333:   Mat                B = mat->B;
2334:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2336:   PetscFunctionBegin;
2337:   /* When a process holds entire A and other processes have no entry */
2338:   if (A->cmap->N == n) {
2339:     PetscCall(VecGetArrayWrite(v, &diagA));
2340:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2341:     PetscCall(MatGetRowMin(mat->A, diagV, idx));
2342:     PetscCall(VecDestroy(&diagV));
2343:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2344:     PetscFunctionReturn(PETSC_SUCCESS);
2345:   } else if (n == 0) {
2346:     if (m) {
2347:       PetscCall(VecGetArrayWrite(v, &a));
2348:       for (r = 0; r < m; r++) {
2349:         a[r] = PETSC_MAX_REAL;
2350:         if (idx) idx[r] = -1;
2351:       }
2352:       PetscCall(VecRestoreArrayWrite(v, &a));
2353:     }
2354:     PetscFunctionReturn(PETSC_SUCCESS);
2355:   }

2357:   PetscCall(PetscCalloc2(m, &diagIdx, m, &offdiagIdx));
2358:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2359:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2360:   PetscCall(MatGetRowMin(mat->A, diagV, diagIdx));

2362:   /* Get offdiagIdx[] for implicit 0.0 */
2363:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2364:   ba = bav;
2365:   bi = b->i;
2366:   bj = b->j;
2367:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2368:   for (r = 0; r < m; r++) {
2369:     ncols = bi[r + 1] - bi[r];
2370:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2371:       offdiagA[r]   = *ba;
2372:       offdiagIdx[r] = cmap[0];
2373:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2374:       offdiagA[r] = 0.0;

2376:       /* Find first hole in the cmap */
2377:       for (j = 0; j < ncols; j++) {
2378:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2379:         if (col > j && j < cstart) {
2380:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2381:           break;
2382:         } else if (col > j + n && j >= cstart) {
2383:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2384:           break;
2385:         }
2386:       }
2387:       if (j == ncols && ncols < A->cmap->N - n) {
2388:         /* a hole is outside compressed Bcols */
2389:         if (ncols == 0) {
2390:           if (cstart) {
2391:             offdiagIdx[r] = 0;
2392:           } else offdiagIdx[r] = cend;
2393:         } else { /* ncols > 0 */
2394:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2395:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2396:         }
2397:       }
2398:     }

2400:     for (j = 0; j < ncols; j++) {
2401:       if (PetscRealPart(offdiagA[r]) > PetscRealPart(*ba)) {
2402:         offdiagA[r]   = *ba;
2403:         offdiagIdx[r] = cmap[*bj];
2404:       }
2405:       ba++;
2406:       bj++;
2407:     }
2408:   }

2410:   PetscCall(VecGetArrayWrite(v, &a));
2411:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2412:   for (r = 0; r < m; ++r) {
2413:     if (PetscRealPart(diagA[r]) < PetscRealPart(offdiagA[r])) {
2414:       a[r] = diagA[r];
2415:       if (idx) idx[r] = cstart + diagIdx[r];
2416:     } else if (PetscRealPart(diagA[r]) == PetscRealPart(offdiagA[r])) {
2417:       a[r] = diagA[r];
2418:       if (idx) {
2419:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2420:           idx[r] = cstart + diagIdx[r];
2421:         } else idx[r] = offdiagIdx[r];
2422:       }
2423:     } else {
2424:       a[r] = offdiagA[r];
2425:       if (idx) idx[r] = offdiagIdx[r];
2426:     }
2427:   }
2428:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2429:   PetscCall(VecRestoreArrayWrite(v, &a));
2430:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2431:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2432:   PetscCall(VecDestroy(&diagV));
2433:   PetscCall(VecDestroy(&offdiagV));
2434:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2435:   PetscFunctionReturn(PETSC_SUCCESS);
2436: }

2438: static PetscErrorCode MatGetRowMax_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2439: {
2440:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2441:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2442:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2443:   PetscInt          *cmap = mat->garray;
2444:   PetscInt          *diagIdx, *offdiagIdx;
2445:   Vec                diagV, offdiagV;
2446:   PetscScalar       *a, *diagA, *offdiagA;
2447:   const PetscScalar *ba, *bav;
2448:   PetscInt           r, j, col, ncols, *bi, *bj;
2449:   Mat                B = mat->B;
2450:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2452:   PetscFunctionBegin;
2453:   /* When a process holds entire A and other processes have no entry */
2454:   if (A->cmap->N == n) {
2455:     PetscCall(VecGetArrayWrite(v, &diagA));
2456:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2457:     PetscCall(MatGetRowMax(mat->A, diagV, idx));
2458:     PetscCall(VecDestroy(&diagV));
2459:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2460:     PetscFunctionReturn(PETSC_SUCCESS);
2461:   } else if (n == 0) {
2462:     if (m) {
2463:       PetscCall(VecGetArrayWrite(v, &a));
2464:       for (r = 0; r < m; r++) {
2465:         a[r] = PETSC_MIN_REAL;
2466:         if (idx) idx[r] = -1;
2467:       }
2468:       PetscCall(VecRestoreArrayWrite(v, &a));
2469:     }
2470:     PetscFunctionReturn(PETSC_SUCCESS);
2471:   }

2473:   PetscCall(PetscMalloc2(m, &diagIdx, m, &offdiagIdx));
2474:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2475:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2476:   PetscCall(MatGetRowMax(mat->A, diagV, diagIdx));

2478:   /* Get offdiagIdx[] for implicit 0.0 */
2479:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2480:   ba = bav;
2481:   bi = b->i;
2482:   bj = b->j;
2483:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2484:   for (r = 0; r < m; r++) {
2485:     ncols = bi[r + 1] - bi[r];
2486:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2487:       offdiagA[r]   = *ba;
2488:       offdiagIdx[r] = cmap[0];
2489:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2490:       offdiagA[r] = 0.0;

2492:       /* Find first hole in the cmap */
2493:       for (j = 0; j < ncols; j++) {
2494:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2495:         if (col > j && j < cstart) {
2496:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2497:           break;
2498:         } else if (col > j + n && j >= cstart) {
2499:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2500:           break;
2501:         }
2502:       }
2503:       if (j == ncols && ncols < A->cmap->N - n) {
2504:         /* a hole is outside compressed Bcols */
2505:         if (ncols == 0) {
2506:           if (cstart) {
2507:             offdiagIdx[r] = 0;
2508:           } else offdiagIdx[r] = cend;
2509:         } else { /* ncols > 0 */
2510:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2511:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2512:         }
2513:       }
2514:     }

2516:     for (j = 0; j < ncols; j++) {
2517:       if (PetscRealPart(offdiagA[r]) < PetscRealPart(*ba)) {
2518:         offdiagA[r]   = *ba;
2519:         offdiagIdx[r] = cmap[*bj];
2520:       }
2521:       ba++;
2522:       bj++;
2523:     }
2524:   }

2526:   PetscCall(VecGetArrayWrite(v, &a));
2527:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2528:   for (r = 0; r < m; ++r) {
2529:     if (PetscRealPart(diagA[r]) > PetscRealPart(offdiagA[r])) {
2530:       a[r] = diagA[r];
2531:       if (idx) idx[r] = cstart + diagIdx[r];
2532:     } else if (PetscRealPart(diagA[r]) == PetscRealPart(offdiagA[r])) {
2533:       a[r] = diagA[r];
2534:       if (idx) {
2535:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2536:           idx[r] = cstart + diagIdx[r];
2537:         } else idx[r] = offdiagIdx[r];
2538:       }
2539:     } else {
2540:       a[r] = offdiagA[r];
2541:       if (idx) idx[r] = offdiagIdx[r];
2542:     }
2543:   }
2544:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2545:   PetscCall(VecRestoreArrayWrite(v, &a));
2546:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2547:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2548:   PetscCall(VecDestroy(&diagV));
2549:   PetscCall(VecDestroy(&offdiagV));
2550:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2551:   PetscFunctionReturn(PETSC_SUCCESS);
2552: }

2554: PetscErrorCode MatGetSeqNonzeroStructure_MPIAIJ(Mat mat, Mat *newmat)
2555: {
2556:   Mat *dummy;

2558:   PetscFunctionBegin;
2559:   PetscCall(MatCreateSubMatrix_MPIAIJ_All(mat, MAT_DO_NOT_GET_VALUES, MAT_INITIAL_MATRIX, &dummy));
2560:   *newmat = *dummy;
2561:   PetscCall(PetscFree(dummy));
2562:   PetscFunctionReturn(PETSC_SUCCESS);
2563: }

2565: static PetscErrorCode MatInvertBlockDiagonal_MPIAIJ(Mat A, const PetscScalar **values)
2566: {
2567:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2569:   PetscFunctionBegin;
2570:   PetscCall(MatInvertBlockDiagonal(a->A, values));
2571:   A->factorerrortype = a->A->factorerrortype;
2572:   PetscFunctionReturn(PETSC_SUCCESS);
2573: }

2575: static PetscErrorCode MatSetRandom_MPIAIJ(Mat x, PetscRandom rctx)
2576: {
2577:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)x->data;

2579:   PetscFunctionBegin;
2580:   PetscCheck(x->assembled || x->preallocated, PetscObjectComm((PetscObject)x), PETSC_ERR_ARG_WRONGSTATE, "MatSetRandom on an unassembled and unpreallocated MATMPIAIJ is not allowed");
2581:   PetscCall(MatSetRandom(aij->A, rctx));
2582:   if (x->assembled) {
2583:     PetscCall(MatSetRandom(aij->B, rctx));
2584:   } else {
2585:     PetscCall(MatSetRandomSkipColumnRange_SeqAIJ_Private(aij->B, x->cmap->rstart, x->cmap->rend, rctx));
2586:   }
2587:   PetscCall(MatAssemblyBegin(x, MAT_FINAL_ASSEMBLY));
2588:   PetscCall(MatAssemblyEnd(x, MAT_FINAL_ASSEMBLY));
2589:   PetscFunctionReturn(PETSC_SUCCESS);
2590: }

2592: static PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ(Mat A, PetscBool sc)
2593: {
2594:   PetscFunctionBegin;
2595:   if (sc) A->ops->increaseoverlap = MatIncreaseOverlap_MPIAIJ_Scalable;
2596:   else A->ops->increaseoverlap = MatIncreaseOverlap_MPIAIJ;
2597:   PetscFunctionReturn(PETSC_SUCCESS);
2598: }

2600: /*@
2601:   MatMPIAIJGetNumberNonzeros - gets the number of nonzeros in the matrix on this MPI rank

2603:   Not Collective

2605:   Input Parameter:
2606: . A - the matrix

2608:   Output Parameter:
2609: . nz - the number of nonzeros

2611:   Level: advanced

2613: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`
2614: @*/
2615: PetscErrorCode MatMPIAIJGetNumberNonzeros(Mat A, PetscCount *nz)
2616: {
2617:   Mat_MPIAIJ *maij = (Mat_MPIAIJ *)A->data;
2618:   Mat_SeqAIJ *aaij = (Mat_SeqAIJ *)maij->A->data, *baij = (Mat_SeqAIJ *)maij->B->data;
2619:   PetscBool   isaij;

2621:   PetscFunctionBegin;
2622:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)A, MATMPIAIJ, &isaij));
2623:   PetscCheck(isaij, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Not for type %s", ((PetscObject)A)->type_name);
2624:   *nz = aaij->i[A->rmap->n] + baij->i[A->rmap->n];
2625:   PetscFunctionReturn(PETSC_SUCCESS);
2626: }

2628: /*@
2629:   MatMPIAIJSetUseScalableIncreaseOverlap - Determine if the matrix uses a scalable algorithm to compute the overlap

2631:   Collective

2633:   Input Parameters:
2634: + A  - the matrix
2635: - sc - `PETSC_TRUE` indicates use the scalable algorithm (default is not to use the scalable algorithm)

2637:   Level: advanced

2639: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`
2640: @*/
2641: PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap(Mat A, PetscBool sc)
2642: {
2643:   PetscFunctionBegin;
2644:   PetscTryMethod(A, "MatMPIAIJSetUseScalableIncreaseOverlap_C", (Mat, PetscBool), (A, sc));
2645:   PetscFunctionReturn(PETSC_SUCCESS);
2646: }

2648: PetscErrorCode MatSetFromOptions_MPIAIJ(Mat A, PetscOptionItems PetscOptionsObject)
2649: {
2650:   PetscBool sc = PETSC_FALSE, flg;

2652:   PetscFunctionBegin;
2653:   PetscOptionsHeadBegin(PetscOptionsObject, "MPIAIJ options");
2654:   if (A->ops->increaseoverlap == MatIncreaseOverlap_MPIAIJ_Scalable) sc = PETSC_TRUE;
2655:   PetscCall(PetscOptionsBool("-mat_increase_overlap_scalable", "Use a scalable algorithm to compute the overlap", "MatIncreaseOverlap", sc, &sc, &flg));
2656:   if (flg) PetscCall(MatMPIAIJSetUseScalableIncreaseOverlap(A, sc));
2657:   PetscOptionsHeadEnd();
2658:   PetscFunctionReturn(PETSC_SUCCESS);
2659: }

2661: static PetscErrorCode MatShift_MPIAIJ(Mat Y, PetscScalar a)
2662: {
2663:   Mat_MPIAIJ *maij = (Mat_MPIAIJ *)Y->data;
2664:   Mat_SeqAIJ *aij  = (Mat_SeqAIJ *)maij->A->data;

2666:   PetscFunctionBegin;
2667:   if (!Y->preallocated) {
2668:     PetscCall(MatMPIAIJSetPreallocation(Y, 1, NULL, 0, NULL));
2669:   } else if (!aij->nz) { /* It does not matter if diagonals of Y only partially lie in maij->A. We just need an estimated preallocation. */
2670:     PetscInt nonew = aij->nonew;
2671:     PetscCall(MatSeqAIJSetPreallocation(maij->A, 1, NULL));
2672:     aij->nonew = nonew;
2673:   }
2674:   PetscCall(MatShift_Basic(Y, a));
2675:   PetscFunctionReturn(PETSC_SUCCESS);
2676: }

2678: static PetscErrorCode MatInvertVariableBlockDiagonal_MPIAIJ(Mat A, PetscInt nblocks, const PetscInt *bsizes, PetscScalar *diag)
2679: {
2680:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2682:   PetscFunctionBegin;
2683:   PetscCall(MatInvertVariableBlockDiagonal(a->A, nblocks, bsizes, diag));
2684:   PetscFunctionReturn(PETSC_SUCCESS);
2685: }

2687: static PetscErrorCode MatEliminateZeros_MPIAIJ(Mat A, PetscBool keep)
2688: {
2689:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2691:   PetscFunctionBegin;
2692:   PetscCall(MatEliminateZeros_SeqAIJ(a->A, keep));        // possibly keep zero diagonal coefficients
2693:   PetscCall(MatEliminateZeros_SeqAIJ(a->B, PETSC_FALSE)); // never keep zero diagonal coefficients
2694:   PetscFunctionReturn(PETSC_SUCCESS);
2695: }

2697: static PetscErrorCode MatGetOrdering_MPIAIJ(Mat A, MatOrderingType type, IS *rperm, IS *cperm)
2698: {
2699:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)A->data;
2700:   IS              lrowperm, lcolperm;
2701:   PetscInt        i, rstart, rend, *idx;
2702:   const PetscInt *lidx;

2704:   PetscFunctionBegin;
2705:   PetscCall(MatGetOrdering(a->A, type, &lrowperm, &lcolperm));
2706:   PetscCall(MatGetOwnershipRange(A, &rstart, &rend));
2707:   /* Remap row index set to global space */
2708:   PetscCall(ISGetIndices(lrowperm, &lidx));
2709:   PetscCall(PetscMalloc1(rend - rstart, &idx));
2710:   for (i = 0; i + rstart < rend; i++) idx[i] = rstart + lidx[i];
2711:   PetscCall(ISRestoreIndices(lrowperm, &lidx));
2712:   PetscCall(ISDestroy(&lrowperm));
2713:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)A), rend - rstart, idx, PETSC_OWN_POINTER, rperm));
2714:   PetscCall(ISSetPermutation(*rperm));
2715:   /* Remap column index set to global space */
2716:   PetscCall(ISGetIndices(lcolperm, &lidx));
2717:   PetscCall(PetscMalloc1(rend - rstart, &idx));
2718:   for (i = 0; i + rstart < rend; i++) idx[i] = rstart + lidx[i];
2719:   PetscCall(ISRestoreIndices(lcolperm, &lidx));
2720:   PetscCall(ISDestroy(&lcolperm));
2721:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)A), rend - rstart, idx, PETSC_OWN_POINTER, cperm));
2722:   PetscCall(ISSetPermutation(*cperm));
2723:   PetscFunctionReturn(PETSC_SUCCESS);
2724: }

2726: static struct _MatOps MatOps_Values = {MatSetValues_MPIAIJ,
2727:                                        MatGetRow_MPIAIJ,
2728:                                        MatRestoreRow_MPIAIJ,
2729:                                        MatMult_MPIAIJ,
2730:                                        /* 4*/ MatMultAdd_MPIAIJ,
2731:                                        MatMultTranspose_MPIAIJ,
2732:                                        MatMultTransposeAdd_MPIAIJ,
2733:                                        NULL,
2734:                                        NULL,
2735:                                        NULL,
2736:                                        /*10*/ NULL,
2737:                                        NULL,
2738:                                        NULL,
2739:                                        MatSOR_MPIAIJ,
2740:                                        MatTranspose_MPIAIJ,
2741:                                        /*15*/ MatGetInfo_MPIAIJ,
2742:                                        MatEqual_MPIAIJ,
2743:                                        MatGetDiagonal_MPIAIJ,
2744:                                        MatDiagonalScale_MPIAIJ,
2745:                                        MatNorm_MPIAIJ,
2746:                                        /*20*/ MatAssemblyBegin_MPIAIJ,
2747:                                        MatAssemblyEnd_MPIAIJ,
2748:                                        MatSetOption_MPIAIJ,
2749:                                        MatZeroEntries_MPIAIJ,
2750:                                        /*24*/ MatZeroRows_MPIAIJ,
2751:                                        NULL,
2752:                                        NULL,
2753:                                        NULL,
2754:                                        NULL,
2755:                                        /*29*/ MatSetUp_MPI_Hash,
2756:                                        NULL,
2757:                                        NULL,
2758:                                        MatGetDiagonalBlock_MPIAIJ,
2759:                                        NULL,
2760:                                        /*34*/ MatDuplicate_MPIAIJ,
2761:                                        NULL,
2762:                                        NULL,
2763:                                        NULL,
2764:                                        NULL,
2765:                                        /*39*/ MatAXPY_MPIAIJ,
2766:                                        MatCreateSubMatrices_MPIAIJ,
2767:                                        MatIncreaseOverlap_MPIAIJ,
2768:                                        MatGetValues_MPIAIJ,
2769:                                        MatCopy_MPIAIJ,
2770:                                        /*44*/ MatGetRowMax_MPIAIJ,
2771:                                        MatScale_MPIAIJ,
2772:                                        MatShift_MPIAIJ,
2773:                                        MatDiagonalSet_MPIAIJ,
2774:                                        MatZeroRowsColumns_MPIAIJ,
2775:                                        /*49*/ MatSetRandom_MPIAIJ,
2776:                                        MatGetRowIJ_MPIAIJ,
2777:                                        MatRestoreRowIJ_MPIAIJ,
2778:                                        NULL,
2779:                                        NULL,
2780:                                        /*54*/ MatFDColoringCreate_MPIXAIJ,
2781:                                        NULL,
2782:                                        MatSetUnfactored_MPIAIJ,
2783:                                        MatPermute_MPIAIJ,
2784:                                        NULL,
2785:                                        /*59*/ MatCreateSubMatrix_MPIAIJ,
2786:                                        MatDestroy_MPIAIJ,
2787:                                        MatView_MPIAIJ,
2788:                                        NULL,
2789:                                        NULL,
2790:                                        /*64*/ MatMatMatMultNumeric_MPIAIJ_MPIAIJ_MPIAIJ,
2791:                                        NULL,
2792:                                        NULL,
2793:                                        NULL,
2794:                                        MatGetRowMaxAbs_MPIAIJ,
2795:                                        /*69*/ MatGetRowMinAbs_MPIAIJ,
2796:                                        NULL,
2797:                                        NULL,
2798:                                        MatFDColoringApply_AIJ,
2799:                                        MatSetFromOptions_MPIAIJ,
2800:                                        MatFindZeroDiagonals_MPIAIJ,
2801:                                        /*75*/ NULL,
2802:                                        NULL,
2803:                                        NULL,
2804:                                        MatLoad_MPIAIJ,
2805:                                        NULL,
2806:                                        /*80*/ NULL,
2807:                                        NULL,
2808:                                        NULL,
2809:                                        /*83*/ NULL,
2810:                                        NULL,
2811:                                        MatMatMultNumeric_MPIAIJ_MPIAIJ,
2812:                                        MatPtAPNumeric_MPIAIJ_MPIAIJ,
2813:                                        NULL,
2814:                                        NULL,
2815:                                        /*89*/ MatBindToCPU_MPIAIJ,
2816:                                        MatProductSetFromOptions_MPIAIJ,
2817:                                        NULL,
2818:                                        NULL,
2819:                                        MatConjugate_MPIAIJ,
2820:                                        /*94*/ NULL,
2821:                                        MatSetValuesRow_MPIAIJ,
2822:                                        MatRealPart_MPIAIJ,
2823:                                        MatImaginaryPart_MPIAIJ,
2824:                                        NULL,
2825:                                        /*99*/ NULL,
2826:                                        NULL,
2827:                                        NULL,
2828:                                        MatGetRowMin_MPIAIJ,
2829:                                        NULL,
2830:                                        /*104*/ MatGetSeqNonzeroStructure_MPIAIJ,
2831:                                        NULL,
2832:                                        MatGetGhosts_MPIAIJ,
2833:                                        NULL,
2834:                                        NULL,
2835:                                        /*109*/ MatMultDiagonalBlock_MPIAIJ,
2836:                                        NULL,
2837:                                        NULL,
2838:                                        NULL,
2839:                                        MatGetMultiProcBlock_MPIAIJ,
2840:                                        /*114*/ MatFindNonzeroRows_MPIAIJ,
2841:                                        MatGetColumnReductions_MPIAIJ,
2842:                                        MatInvertBlockDiagonal_MPIAIJ,
2843:                                        MatInvertVariableBlockDiagonal_MPIAIJ,
2844:                                        MatCreateSubMatricesMPI_MPIAIJ,
2845:                                        /*119*/ NULL,
2846:                                        MatTransposeMatMultNumeric_MPIAIJ_MPIAIJ,
2847:                                        NULL,
2848:                                        NULL,
2849:                                        NULL,
2850:                                        /*124*/ NULL,
2851:                                        MatSetBlockSizes_MPIAIJ,
2852:                                        NULL,
2853:                                        MatFDColoringSetUp_MPIXAIJ,
2854:                                        MatFindOffBlockDiagonalEntries_MPIAIJ,
2855:                                        /*129*/ MatCreateMPIMatConcatenateSeqMat_MPIAIJ,
2856:                                        NULL,
2857:                                        NULL,
2858:                                        NULL,
2859:                                        MatCreateGraph_Simple_AIJ,
2860:                                        /*134*/ NULL,
2861:                                        MatEliminateZeros_MPIAIJ,
2862:                                        MatGetRowSumAbs_MPIAIJ,
2863:                                        NULL,
2864:                                        NULL,
2865:                                        /*139*/ NULL,
2866:                                        MatCopyHashToXAIJ_MPI_Hash,
2867:                                        MatGetCurrentMemType_MPIAIJ,
2868:                                        NULL,
2869:                                        MatADot_Default,
2870:                                        /*144*/ MatANorm_Default,
2871:                                        NULL,
2872:                                        NULL,
2873:                                        MatGetOrdering_MPIAIJ};

2875: static PetscErrorCode MatStoreValues_MPIAIJ(Mat mat)
2876: {
2877:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2879:   PetscFunctionBegin;
2880:   PetscCall(MatStoreValues(aij->A));
2881:   PetscCall(MatStoreValues(aij->B));
2882:   PetscFunctionReturn(PETSC_SUCCESS);
2883: }

2885: static PetscErrorCode MatRetrieveValues_MPIAIJ(Mat mat)
2886: {
2887:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2889:   PetscFunctionBegin;
2890:   PetscCall(MatRetrieveValues(aij->A));
2891:   PetscCall(MatRetrieveValues(aij->B));
2892:   PetscFunctionReturn(PETSC_SUCCESS);
2893: }

2895: PetscErrorCode MatMPIAIJSetPreallocation_MPIAIJ(Mat B, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[])
2896: {
2897:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;
2898:   PetscMPIInt size;

2900:   PetscFunctionBegin;
2901:   if (B->hash_active) {
2902:     B->ops[0]      = b->cops;
2903:     B->hash_active = PETSC_FALSE;
2904:   }
2905:   PetscCall(PetscLayoutSetUp(B->rmap));
2906:   PetscCall(PetscLayoutSetUp(B->cmap));

2908: #if PetscDefined(USE_CTABLE)
2909:   PetscCall(PetscHMapIDestroy(&b->colmap));
2910: #else
2911:   PetscCall(PetscFree(b->colmap));
2912: #endif
2913:   PetscCall(PetscFree(b->garray));
2914:   PetscCall(VecDestroy(&b->lvec));
2915:   PetscCall(VecScatterDestroy(&b->Mvctx));

2917:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)B), &size));

2919:   MatSeqXAIJGetOptions_Private(b->B);
2920:   PetscCall(MatDestroy(&b->B));
2921:   PetscCall(MatCreate(PETSC_COMM_SELF, &b->B));
2922:   PetscCall(MatSetSizes(b->B, B->rmap->n, size > 1 ? B->cmap->N : 0, B->rmap->n, size > 1 ? B->cmap->N : 0));
2923:   PetscCall(MatSetBlockSizesFromMats(b->B, B, B));
2924:   PetscCall(MatSetType(b->B, MATSEQAIJ));
2925:   MatSeqXAIJRestoreOptions_Private(b->B);

2927:   MatSeqXAIJGetOptions_Private(b->A);
2928:   PetscCall(MatDestroy(&b->A));
2929:   PetscCall(MatCreate(PETSC_COMM_SELF, &b->A));
2930:   PetscCall(MatSetSizes(b->A, B->rmap->n, B->cmap->n, B->rmap->n, B->cmap->n));
2931:   PetscCall(MatSetBlockSizesFromMats(b->A, B, B));
2932:   PetscCall(MatSetType(b->A, MATSEQAIJ));
2933:   MatSeqXAIJRestoreOptions_Private(b->A);

2935:   PetscCall(MatSeqAIJSetPreallocation(b->A, d_nz, d_nnz));
2936:   PetscCall(MatSeqAIJSetPreallocation(b->B, o_nz, o_nnz));
2937:   B->preallocated  = PETSC_TRUE;
2938:   B->was_assembled = PETSC_FALSE;
2939:   B->assembled     = PETSC_FALSE;
2940:   PetscFunctionReturn(PETSC_SUCCESS);
2941: }

2943: static PetscErrorCode MatResetPreallocation_MPIAIJ(Mat B)
2944: {
2945:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;
2946:   PetscBool   ondiagreset, offdiagreset, memoryreset;

2948:   PetscFunctionBegin;
2950:   PetscCheck(B->insertmode == NOT_SET_VALUES, PETSC_COMM_SELF, PETSC_ERR_SUP, "Cannot reset preallocation after setting some values but not yet calling MatAssemblyBegin()/MatAssemblyEnd()");
2951:   if (B->num_ass == 0) PetscFunctionReturn(PETSC_SUCCESS);

2953:   PetscCall(MatResetPreallocation_SeqAIJ_Private(b->A, &ondiagreset));
2954:   PetscCall(MatResetPreallocation_SeqAIJ_Private(b->B, &offdiagreset));
2955:   memoryreset = (PetscBool)(ondiagreset || offdiagreset);
2956:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &memoryreset, 1, MPI_C_BOOL, MPI_LOR, PetscObjectComm((PetscObject)B)));
2957:   if (!memoryreset) PetscFunctionReturn(PETSC_SUCCESS);

2959:   PetscCall(PetscLayoutSetUp(B->rmap));
2960:   PetscCall(PetscLayoutSetUp(B->cmap));
2961:   PetscCheck(B->assembled || B->was_assembled, PetscObjectComm((PetscObject)B), PETSC_ERR_ARG_WRONGSTATE, "Should not need to reset preallocation if the matrix was never assembled");
2962:   PetscCall(MatDisAssemble_MPIAIJ(B, PETSC_TRUE));
2963:   PetscCall(VecScatterDestroy(&b->Mvctx));

2965:   B->preallocated  = PETSC_TRUE;
2966:   B->was_assembled = PETSC_FALSE;
2967:   B->assembled     = PETSC_FALSE;
2968:   /* Log that the state of this object has changed; this will help guarantee that preconditioners get re-setup */
2969:   PetscCall(PetscObjectStateIncrease((PetscObject)B));
2970:   PetscFunctionReturn(PETSC_SUCCESS);
2971: }

2973: PetscErrorCode MatDuplicate_MPIAIJ(Mat matin, MatDuplicateOption cpvalues, Mat *newmat)
2974: {
2975:   Mat         mat;
2976:   Mat_MPIAIJ *a, *oldmat = (Mat_MPIAIJ *)matin->data;

2978:   PetscFunctionBegin;
2979:   *newmat = NULL;
2980:   PetscCall(MatCreate(PetscObjectComm((PetscObject)matin), &mat));
2981:   PetscCall(MatSetSizes(mat, matin->rmap->n, matin->cmap->n, matin->rmap->N, matin->cmap->N));
2982:   PetscCall(MatSetBlockSizesFromMats(mat, matin, matin));
2983:   PetscCall(MatSetType(mat, ((PetscObject)matin)->type_name));
2984:   a = (Mat_MPIAIJ *)mat->data;

2986:   mat->factortype = matin->factortype;
2987:   mat->assembled  = matin->assembled;
2988:   mat->insertmode = NOT_SET_VALUES;

2990:   a->size         = oldmat->size;
2991:   a->rank         = oldmat->rank;
2992:   a->donotstash   = oldmat->donotstash;
2993:   a->roworiented  = oldmat->roworiented;
2994:   a->rowindices   = NULL;
2995:   a->rowvalues    = NULL;
2996:   a->getrowactive = PETSC_FALSE;

2998:   PetscCall(PetscLayoutReference(matin->rmap, &mat->rmap));
2999:   PetscCall(PetscLayoutReference(matin->cmap, &mat->cmap));
3000:   if (matin->hash_active) PetscCall(MatSetUp(mat));
3001:   else {
3002:     mat->preallocated = matin->preallocated;
3003:     if (oldmat->colmap) {
3004: #if PetscDefined(USE_CTABLE)
3005:       PetscCall(PetscHMapIDuplicate(oldmat->colmap, &a->colmap));
3006: #else
3007:       PetscCall(PetscMalloc1(mat->cmap->N, &a->colmap));
3008:       PetscCall(PetscArraycpy(a->colmap, oldmat->colmap, mat->cmap->N));
3009: #endif
3010:     } else a->colmap = NULL;
3011:     if (oldmat->garray) {
3012:       PetscInt len;
3013:       len = oldmat->B->cmap->n;
3014:       PetscCall(PetscMalloc1(len, &a->garray));
3015:       if (len) PetscCall(PetscArraycpy(a->garray, oldmat->garray, len));
3016:     } else a->garray = NULL;

3018:     /* It may happen MatDuplicate is called with a non-assembled matrix
3019:       In fact, MatDuplicate only requires the matrix to be preallocated
3020:       This may happen inside a DMCreateMatrix_Shell */
3021:     if (oldmat->lvec) PetscCall(VecDuplicate(oldmat->lvec, &a->lvec));
3022:     if (oldmat->Mvctx) {
3023:       a->Mvctx = oldmat->Mvctx;
3024:       PetscCall(PetscObjectReference((PetscObject)oldmat->Mvctx));
3025:     }
3026:     PetscCall(MatDuplicate(oldmat->A, cpvalues, &a->A));
3027:     PetscCall(MatDuplicate(oldmat->B, cpvalues, &a->B));
3028:   }
3029:   PetscCall(PetscFunctionListDuplicate(((PetscObject)matin)->qlist, &((PetscObject)mat)->qlist));
3030:   *newmat = mat;
3031:   PetscFunctionReturn(PETSC_SUCCESS);
3032: }

3034: PetscErrorCode MatLoad_MPIAIJ(Mat newMat, PetscViewer viewer)
3035: {
3036:   PetscBool isbinary, ishdf5;

3038:   PetscFunctionBegin;
3041:   /* force binary viewer to load .info file if it has not yet done so */
3042:   PetscCall(PetscViewerSetUp(viewer));
3043:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
3044:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERHDF5, &ishdf5));
3045:   if (isbinary) {
3046:     PetscCall(MatLoad_MPIAIJ_Binary(newMat, viewer));
3047:   } else if (ishdf5) {
3048: #if PetscDefined(HAVE_HDF5)
3049:     PetscCall(MatLoad_AIJ_HDF5(newMat, viewer));
3050: #else
3051:     SETERRQ(PetscObjectComm((PetscObject)newMat), PETSC_ERR_SUP, "HDF5 not supported in this build.\nPlease reconfigure using --download-hdf5");
3052: #endif
3053:   } else {
3054:     SETERRQ(PetscObjectComm((PetscObject)newMat), PETSC_ERR_SUP, "Viewer type %s not yet supported for reading %s matrices", ((PetscObject)viewer)->type_name, ((PetscObject)newMat)->type_name);
3055:   }
3056:   PetscFunctionReturn(PETSC_SUCCESS);
3057: }

3059: PetscErrorCode MatLoad_MPIAIJ_Binary(Mat mat, PetscViewer viewer)
3060: {
3061:   PetscInt     header[4], M, N, m, nz, rows, cols, sum, i;
3062:   PetscInt    *rowidxs, *colidxs;
3063:   PetscScalar *matvals;

3065:   PetscFunctionBegin;
3066:   PetscCall(PetscViewerSetUp(viewer));

3068:   /* read in matrix header */
3069:   PetscCall(PetscViewerBinaryRead(viewer, header, 4, NULL, PETSC_INT));
3070:   PetscCheck(header[0] == MAT_FILE_CLASSID, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Not a matrix object in file");
3071:   M  = header[1];
3072:   N  = header[2];
3073:   nz = header[3];
3074:   PetscCheck(M >= 0, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Matrix row size (%" PetscInt_FMT ") in file is negative", M);
3075:   PetscCheck(N >= 0, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Matrix column size (%" PetscInt_FMT ") in file is negative", N);
3076:   PetscCheck(nz >= 0, PETSC_COMM_SELF, PETSC_ERR_FILE_UNEXPECTED, "Matrix stored in special format on disk, cannot load as MPIAIJ");

3078:   /* set block sizes from the viewer's .info file */
3079:   PetscCall(MatLoad_Binary_BlockSizes(mat, viewer));
3080:   /* set global sizes if not set already */
3081:   if (mat->rmap->N < 0) mat->rmap->N = M;
3082:   if (mat->cmap->N < 0) mat->cmap->N = N;
3083:   PetscCall(PetscLayoutSetUp(mat->rmap));
3084:   PetscCall(PetscLayoutSetUp(mat->cmap));

3086:   /* check if the matrix sizes are correct */
3087:   PetscCall(MatGetSize(mat, &rows, &cols));
3088:   PetscCheck(M == rows && N == cols, PETSC_COMM_SELF, PETSC_ERR_FILE_UNEXPECTED, "Matrix in file of different sizes (%" PetscInt_FMT ", %" PetscInt_FMT ") than the input matrix (%" PetscInt_FMT ", %" PetscInt_FMT ")", M, N, rows, cols);

3090:   /* read in row lengths and build row indices */
3091:   PetscCall(MatGetLocalSize(mat, &m, NULL));
3092:   PetscCall(PetscMalloc1(m + 1, &rowidxs));
3093:   PetscCall(PetscViewerBinaryReadAll(viewer, rowidxs + 1, m, PETSC_DECIDE, M, PETSC_INT));
3094:   rowidxs[0] = 0;
3095:   for (i = 0; i < m; i++) rowidxs[i + 1] += rowidxs[i];
3096:   if (nz != PETSC_INT_MAX) {
3097:     PetscCallMPI(MPIU_Allreduce(&rowidxs[m], &sum, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)viewer)));
3098:     PetscCheck(sum == nz, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Inconsistent matrix data in file: nonzeros = %" PetscInt_FMT ", sum-row-lengths = %" PetscInt_FMT, nz, sum);
3099:   }

3101:   /* read in column indices and matrix values */
3102:   PetscCall(PetscMalloc2(rowidxs[m], &colidxs, rowidxs[m], &matvals));
3103:   PetscCall(PetscViewerBinaryReadAll(viewer, colidxs, rowidxs[m], PETSC_DETERMINE, PETSC_DETERMINE, PETSC_INT));
3104:   PetscCall(PetscViewerBinaryReadAll(viewer, matvals, rowidxs[m], PETSC_DETERMINE, PETSC_DETERMINE, PETSC_SCALAR));
3105:   /* store matrix indices and values */
3106:   PetscCall(MatMPIAIJSetPreallocationCSR(mat, rowidxs, colidxs, matvals));
3107:   PetscCall(PetscFree(rowidxs));
3108:   PetscCall(PetscFree2(colidxs, matvals));
3109:   PetscFunctionReturn(PETSC_SUCCESS);
3110: }

3112: /* Not scalable because of ISAllGather() unless getting all columns. */
3113: static PetscErrorCode ISGetSeqIS_Private(Mat mat, IS iscol, IS *isseq)
3114: {
3115:   IS          iscol_local;
3116:   PetscBool   isstride;
3117:   PetscMPIInt gisstride = 0;

3119:   PetscFunctionBegin;
3120:   /* check if we are grabbing all columns*/
3121:   PetscCall(PetscObjectTypeCompare((PetscObject)iscol, ISSTRIDE, &isstride));

3123:   if (isstride) {
3124:     PetscInt start, len, mstart, mlen;
3125:     PetscCall(ISStrideGetInfo(iscol, &start, NULL));
3126:     PetscCall(ISGetLocalSize(iscol, &len));
3127:     PetscCall(MatGetOwnershipRangeColumn(mat, &mstart, &mlen));
3128:     if (mstart == start && mlen - mstart == len) gisstride = 1;
3129:   }

3131:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &gisstride, 1, MPI_INT, MPI_MIN, PetscObjectComm((PetscObject)mat)));
3132:   if (gisstride) {
3133:     PetscInt N;
3134:     PetscCall(MatGetSize(mat, NULL, &N));
3135:     PetscCall(ISCreateStride(PETSC_COMM_SELF, N, 0, 1, &iscol_local));
3136:     PetscCall(ISSetIdentity(iscol_local));
3137:     PetscCall(PetscInfo(mat, "Optimizing for obtaining all columns of the matrix; skipping ISAllGather()\n"));
3138:   } else {
3139:     PetscInt cbs;
3140:     PetscCall(ISGetBlockSize(iscol, &cbs));
3141:     PetscCall(ISAllGather(iscol, &iscol_local));
3142:     PetscCall(ISSetBlockSize(iscol_local, cbs));
3143:   }

3145:   *isseq = iscol_local;
3146:   PetscFunctionReturn(PETSC_SUCCESS);
3147: }

3149: /*
3150:  Used by MatCreateSubMatrix_MPIAIJ_SameRowColDist() to avoid ISAllGather() and global size of iscol_local
3151:  (see MatCreateSubMatrix_MPIAIJ_nonscalable)

3153:  Input Parameters:
3154: +   mat - matrix
3155: .   isrow - parallel row index set; its local indices are a subset of local columns of `mat`,
3156:            i.e., mat->rstart <= isrow[i] < mat->rend
3157: -   iscol - parallel column index set; its local indices are a subset of local columns of `mat`,
3158:            i.e., mat->cstart <= iscol[i] < mat->cend

3160:  Output Parameters:
3161: +   isrow_d - sequential row index set for retrieving mat->A
3162: .   iscol_d - sequential  column index set for retrieving mat->A
3163: .   iscol_o - sequential column index set for retrieving mat->B
3164: -   garray - column map; garray[i] indicates global location of iscol_o[i] in `iscol`
3165:  */
3166: static PetscErrorCode ISGetSeqIS_SameColDist_Private(Mat mat, IS isrow, IS iscol, IS *isrow_d, IS *iscol_d, IS *iscol_o, PetscInt *garray[])
3167: {
3168:   Vec             x, cmap;
3169:   const PetscInt *is_idx;
3170:   PetscScalar    *xarray, *cmaparray;
3171:   PetscInt        ncols, isstart, *idx, m, rstart, *cmap1, count;
3172:   Mat_MPIAIJ     *a    = (Mat_MPIAIJ *)mat->data;
3173:   Mat             B    = a->B;
3174:   Vec             lvec = a->lvec, lcmap;
3175:   PetscInt        i, cstart, cend, Bn = B->cmap->N;
3176:   MPI_Comm        comm;
3177:   VecScatter      Mvctx = a->Mvctx;

3179:   PetscFunctionBegin;
3180:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3181:   PetscCall(ISGetLocalSize(iscol, &ncols));

3183:   /* (1) iscol is a sub-column vector of mat, pad it with '-1.' to form a full vector x */
3184:   PetscCall(MatCreateVecs(mat, &x, NULL));
3185:   PetscCall(VecSet(x, -1.0));
3186:   PetscCall(VecDuplicate(x, &cmap));
3187:   PetscCall(VecSet(cmap, -1.0));

3189:   /* Get start indices */
3190:   PetscCallMPI(MPI_Scan(&ncols, &isstart, 1, MPIU_INT, MPI_SUM, comm));
3191:   isstart -= ncols;
3192:   PetscCall(MatGetOwnershipRangeColumn(mat, &cstart, &cend));

3194:   PetscCall(ISGetIndices(iscol, &is_idx));
3195:   PetscCall(VecGetArray(x, &xarray));
3196:   PetscCall(VecGetArray(cmap, &cmaparray));
3197:   PetscCall(PetscMalloc1(ncols, &idx));
3198:   for (i = 0; i < ncols; i++) {
3199:     xarray[is_idx[i] - cstart]    = (PetscScalar)is_idx[i];
3200:     cmaparray[is_idx[i] - cstart] = i + isstart;        /* global index of iscol[i] */
3201:     idx[i]                        = is_idx[i] - cstart; /* local index of iscol[i]  */
3202:   }
3203:   PetscCall(VecRestoreArray(x, &xarray));
3204:   PetscCall(VecRestoreArray(cmap, &cmaparray));
3205:   PetscCall(ISRestoreIndices(iscol, &is_idx));

3207:   /* Get iscol_d */
3208:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, iscol_d));
3209:   PetscCall(ISGetBlockSize(iscol, &i));
3210:   PetscCall(ISSetBlockSize(*iscol_d, i));

3212:   /* Get isrow_d */
3213:   PetscCall(ISGetLocalSize(isrow, &m));
3214:   rstart = mat->rmap->rstart;
3215:   PetscCall(PetscMalloc1(m, &idx));
3216:   PetscCall(ISGetIndices(isrow, &is_idx));
3217:   for (i = 0; i < m; i++) idx[i] = is_idx[i] - rstart;
3218:   PetscCall(ISRestoreIndices(isrow, &is_idx));

3220:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, m, idx, PETSC_OWN_POINTER, isrow_d));
3221:   PetscCall(ISGetBlockSize(isrow, &i));
3222:   PetscCall(ISSetBlockSize(*isrow_d, i));

3224:   /* (2) Scatter x and cmap using aij->Mvctx to get their off-process portions (see MatMult_MPIAIJ) */
3225:   PetscCall(VecScatterBegin(Mvctx, x, lvec, INSERT_VALUES, SCATTER_FORWARD));
3226:   PetscCall(VecScatterEnd(Mvctx, x, lvec, INSERT_VALUES, SCATTER_FORWARD));

3228:   PetscCall(VecDuplicate(lvec, &lcmap));

3230:   PetscCall(VecScatterBegin(Mvctx, cmap, lcmap, INSERT_VALUES, SCATTER_FORWARD));
3231:   PetscCall(VecScatterEnd(Mvctx, cmap, lcmap, INSERT_VALUES, SCATTER_FORWARD));

3233:   /* (3) create sequential iscol_o (a subset of iscol) and isgarray */
3234:   /* off-process column indices */
3235:   count = 0;
3236:   PetscCall(PetscMalloc1(Bn, &idx));
3237:   PetscCall(PetscMalloc1(Bn, &cmap1));

3239:   PetscCall(VecGetArray(lvec, &xarray));
3240:   PetscCall(VecGetArray(lcmap, &cmaparray));
3241:   for (i = 0; i < Bn; i++) {
3242:     if (PetscRealPart(xarray[i]) > -1.0) {
3243:       idx[count]   = i;                                     /* local column index in off-diagonal part B */
3244:       cmap1[count] = (PetscInt)PetscRealPart(cmaparray[i]); /* column index in submat */
3245:       count++;
3246:     }
3247:   }
3248:   PetscCall(VecRestoreArray(lvec, &xarray));
3249:   PetscCall(VecRestoreArray(lcmap, &cmaparray));

3251:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count, idx, PETSC_COPY_VALUES, iscol_o));
3252:   /* cannot ensure iscol_o has same blocksize as iscol! */

3254:   PetscCall(PetscFree(idx));
3255:   *garray = cmap1;

3257:   PetscCall(VecDestroy(&x));
3258:   PetscCall(VecDestroy(&cmap));
3259:   PetscCall(VecDestroy(&lcmap));
3260:   PetscFunctionReturn(PETSC_SUCCESS);
3261: }

3263: /* isrow and iscol have same processor distribution as mat, output *submat is a submatrix of local mat */
3264: PetscErrorCode MatCreateSubMatrix_MPIAIJ_SameRowColDist(Mat mat, IS isrow, IS iscol, MatReuse call, Mat *submat)
3265: {
3266:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)mat->data, *asub;
3267:   Mat         M = NULL;
3268:   MPI_Comm    comm;
3269:   IS          iscol_d, isrow_d, iscol_o;
3270:   Mat         Asub = NULL, Bsub = NULL;
3271:   PetscInt    n, count, M_size, N_size;

3273:   PetscFunctionBegin;
3274:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));

3276:   if (call == MAT_REUSE_MATRIX) {
3277:     /* Retrieve isrow_d, iscol_d and iscol_o from submat */
3278:     PetscCall(PetscObjectQuery((PetscObject)*submat, "isrow_d", (PetscObject *)&isrow_d));
3279:     PetscCheck(isrow_d, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "isrow_d passed in was not used before, cannot reuse");

3281:     PetscCall(PetscObjectQuery((PetscObject)*submat, "iscol_d", (PetscObject *)&iscol_d));
3282:     PetscCheck(iscol_d, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "iscol_d passed in was not used before, cannot reuse");

3284:     PetscCall(PetscObjectQuery((PetscObject)*submat, "iscol_o", (PetscObject *)&iscol_o));
3285:     PetscCheck(iscol_o, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "iscol_o passed in was not used before, cannot reuse");

3287:     /* Update diagonal and off-diagonal portions of submat */
3288:     asub = (Mat_MPIAIJ *)(*submat)->data;
3289:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->A, isrow_d, iscol_d, PETSC_DECIDE, MAT_REUSE_MATRIX, &asub->A));
3290:     PetscCall(ISGetLocalSize(iscol_o, &n));
3291:     if (n) PetscCall(MatCreateSubMatrix_SeqAIJ(a->B, isrow_d, iscol_o, PETSC_DECIDE, MAT_REUSE_MATRIX, &asub->B));
3292:     PetscCall(MatAssemblyBegin(*submat, MAT_FINAL_ASSEMBLY));
3293:     PetscCall(MatAssemblyEnd(*submat, MAT_FINAL_ASSEMBLY));

3295:   } else { /* call == MAT_INITIAL_MATRIX) */
3296:     PetscInt *garray, *garray_compact;
3297:     PetscInt  BsubN;

3299:     /* Create isrow_d, iscol_d, iscol_o and isgarray (replace isgarray with array?) */
3300:     PetscCall(ISGetSeqIS_SameColDist_Private(mat, isrow, iscol, &isrow_d, &iscol_d, &iscol_o, &garray));

3302:     /* Create local submatrices Asub and Bsub */
3303:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->A, isrow_d, iscol_d, PETSC_DECIDE, MAT_INITIAL_MATRIX, &Asub));
3304:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->B, isrow_d, iscol_o, PETSC_DECIDE, MAT_INITIAL_MATRIX, &Bsub));

3306:     // Compact garray so its not of size Bn
3307:     PetscCall(ISGetSize(iscol_o, &count));
3308:     PetscCall(PetscMalloc1(count, &garray_compact));
3309:     PetscCall(PetscArraycpy(garray_compact, garray, count));

3311:     /* Create submatrix M */
3312:     PetscCall(ISGetSize(isrow, &M_size));
3313:     PetscCall(ISGetSize(iscol, &N_size));
3314:     PetscCall(MatCreateMPIAIJWithSeqAIJ(comm, M_size, N_size, Asub, Bsub, garray_compact, &M));

3316:     /* If Bsub has empty columns, compress iscol_o such that it will retrieve condensed Bsub from a->B during reuse */
3317:     asub = (Mat_MPIAIJ *)M->data;

3319:     PetscCall(ISGetLocalSize(iscol_o, &BsubN));
3320:     n = asub->B->cmap->N;
3321:     if (BsubN > n) {
3322:       /* This case can be tested using ~petsc/src/tao/bound/tutorials/runplate2_3 */
3323:       const PetscInt *idx;
3324:       PetscInt        i, j, *idx_new, *subgarray = asub->garray;
3325:       PetscCall(PetscInfo(M, "submatrix Bn %" PetscInt_FMT " != BsubN %" PetscInt_FMT ", update iscol_o\n", n, BsubN));

3327:       PetscCall(PetscMalloc1(n, &idx_new));
3328:       j = 0;
3329:       PetscCall(ISGetIndices(iscol_o, &idx));
3330:       for (i = 0; i < n; i++) {
3331:         if (j >= BsubN) break;
3332:         while (subgarray[i] > garray[j]) j++;

3334:         PetscCheck(subgarray[i] == garray[j], PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "subgarray[%" PetscInt_FMT "]=%" PetscInt_FMT " cannot < garray[%" PetscInt_FMT "]=%" PetscInt_FMT, i, subgarray[i], j, garray[j]);
3335:         idx_new[i] = idx[j++];
3336:       }
3337:       PetscCall(ISRestoreIndices(iscol_o, &idx));

3339:       PetscCall(ISDestroy(&iscol_o));
3340:       PetscCall(ISCreateGeneral(PETSC_COMM_SELF, n, idx_new, PETSC_OWN_POINTER, &iscol_o));

3342:     } else PetscCheck(BsubN >= n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Columns of Bsub (%" PetscInt_FMT ") cannot be smaller than B's (%" PetscInt_FMT ")", BsubN, asub->B->cmap->N);

3344:     PetscCall(PetscFree(garray));
3345:     *submat = M;

3347:     /* Save isrow_d, iscol_d and iscol_o used in processor for next request */
3348:     PetscCall(PetscObjectCompose((PetscObject)M, "isrow_d", (PetscObject)isrow_d));
3349:     PetscCall(ISDestroy(&isrow_d));

3351:     PetscCall(PetscObjectCompose((PetscObject)M, "iscol_d", (PetscObject)iscol_d));
3352:     PetscCall(ISDestroy(&iscol_d));

3354:     PetscCall(PetscObjectCompose((PetscObject)M, "iscol_o", (PetscObject)iscol_o));
3355:     PetscCall(ISDestroy(&iscol_o));
3356:   }
3357:   PetscFunctionReturn(PETSC_SUCCESS);
3358: }

3360: PetscErrorCode MatCreateSubMatrix_MPIAIJ(Mat mat, IS isrow, IS iscol, MatReuse call, Mat *newmat)
3361: {
3362:   IS        iscol_local = NULL, isrow_d;
3363:   PetscInt  csize;
3364:   PetscInt  n, i, j, start, end;
3365:   PetscBool sameRowDist = PETSC_FALSE, tsameDist[2];
3366:   MPI_Comm  comm;

3368:   PetscFunctionBegin;
3369:   /* If isrow has same processor distribution as mat,
3370:      call MatCreateSubMatrix_MPIAIJ_SameRowDist() to avoid using a hash table with global size of iscol */
3371:   if (call == MAT_REUSE_MATRIX) {
3372:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "isrow_d", (PetscObject *)&isrow_d));
3373:     if (isrow_d) {
3374:       sameRowDist  = PETSC_TRUE;
3375:       tsameDist[1] = PETSC_TRUE; /* sameColDist */
3376:     } else {
3377:       PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_local));
3378:       if (iscol_local) {
3379:         sameRowDist  = PETSC_TRUE;
3380:         tsameDist[1] = PETSC_FALSE; /* !sameColDist */
3381:       }
3382:     }
3383:   } else {
3384:     /* Check if isrow has same processor distribution as mat */
3385:     tsameDist[0] = PETSC_FALSE;
3386:     PetscCall(ISGetLocalSize(isrow, &n));
3387:     if (!n) {
3388:       tsameDist[0] = PETSC_TRUE;
3389:     } else {
3390:       PetscCall(ISGetMinMax(isrow, &i, &j));
3391:       PetscCall(MatGetOwnershipRange(mat, &start, &end));
3392:       if (i >= start && j < end) tsameDist[0] = PETSC_TRUE;
3393:     }

3395:     /* Check if iscol has same processor distribution as mat */
3396:     tsameDist[1] = PETSC_FALSE;
3397:     PetscCall(ISGetLocalSize(iscol, &n));
3398:     if (!n) {
3399:       tsameDist[1] = PETSC_TRUE;
3400:     } else {
3401:       PetscCall(ISGetMinMax(iscol, &i, &j));
3402:       PetscCall(MatGetOwnershipRangeColumn(mat, &start, &end));
3403:       if (i >= start && j < end) tsameDist[1] = PETSC_TRUE;
3404:     }

3406:     PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3407:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, tsameDist, 2, MPI_C_BOOL, MPI_LAND, comm));
3408:     sameRowDist = tsameDist[0];
3409:   }

3411:   if (sameRowDist) {
3412:     if (tsameDist[1]) { /* sameRowDist & sameColDist */
3413:       /* isrow and iscol have same processor distribution as mat */
3414:       PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowColDist(mat, isrow, iscol, call, newmat));
3415:       PetscFunctionReturn(PETSC_SUCCESS);
3416:     } else { /* sameRowDist */
3417:       /* isrow has same processor distribution as mat */
3418:       if (call == MAT_INITIAL_MATRIX) {
3419:         PetscBool sorted;
3420:         PetscCall(ISGetSeqIS_Private(mat, iscol, &iscol_local));
3421:         PetscCall(ISGetLocalSize(iscol_local, &n)); /* local size of iscol_local = global columns of newmat */
3422:         PetscCall(ISGetSize(iscol, &i));
3423:         PetscCheck(n == i, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "n %" PetscInt_FMT " != size of iscol %" PetscInt_FMT, n, i);

3425:         PetscCall(ISSorted(iscol_local, &sorted));
3426:         if (sorted) {
3427:           /* MatCreateSubMatrix_MPIAIJ_SameRowDist() requires iscol_local be sorted; it can have duplicate indices */
3428:           PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowDist(mat, isrow, iscol, iscol_local, MAT_INITIAL_MATRIX, newmat));
3429:           PetscFunctionReturn(PETSC_SUCCESS);
3430:         }
3431:       } else { /* call == MAT_REUSE_MATRIX */
3432:         IS iscol_sub;
3433:         PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_sub));
3434:         if (iscol_sub) {
3435:           PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowDist(mat, isrow, iscol, NULL, call, newmat));
3436:           PetscFunctionReturn(PETSC_SUCCESS);
3437:         }
3438:       }
3439:     }
3440:   }

3442:   /* General case: iscol -> iscol_local which has global size of iscol */
3443:   if (call == MAT_REUSE_MATRIX) {
3444:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "ISAllGather", (PetscObject *)&iscol_local));
3445:     PetscCheck(iscol_local, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");
3446:   } else {
3447:     if (!iscol_local) PetscCall(ISGetSeqIS_Private(mat, iscol, &iscol_local));
3448:   }

3450:   PetscCall(ISGetLocalSize(iscol, &csize));
3451:   PetscCall(MatCreateSubMatrix_MPIAIJ_nonscalable(mat, isrow, iscol_local, csize, call, newmat));

3453:   if (call == MAT_INITIAL_MATRIX) {
3454:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "ISAllGather", (PetscObject)iscol_local));
3455:     PetscCall(ISDestroy(&iscol_local));
3456:   }
3457:   PetscFunctionReturn(PETSC_SUCCESS);
3458: }

3460: /*@C
3461:   MatCreateMPIAIJWithSeqAIJ - creates a `MATMPIAIJ` matrix using `MATSEQAIJ` matrices that contain the "diagonal"
3462:   and "off-diagonal" part of the matrix in CSR format.

3464:   Collective

3466:   Input Parameters:
3467: + comm   - MPI communicator
3468: . M      - the global row size
3469: . N      - the global column size
3470: . A      - "diagonal" portion of matrix
3471: . B      - if garray is `NULL`, B should be the offdiag matrix using global col ids and of size N - if garray is not `NULL`, B should be the offdiag matrix using local col ids and of size garray
3472: - garray - either `NULL` or the global index of `B` columns. If not `NULL`, it should be allocated by `PetscMalloc1()` and will be owned by `mat` thereafter.

3474:   Output Parameter:
3475: . mat - the matrix, with input `A` as its local diagonal matrix

3477:   Level: advanced

3479:   Notes:
3480:   See `MatCreateAIJ()` for the definition of "diagonal" and "off-diagonal" portion of the matrix.

3482:   `A` and `B` becomes part of output mat. The user cannot use `A` and `B` anymore.

3484:   If `garray` is `NULL`, `B` will be compacted to use local indices. In this sense, `B`'s sparsity pattern (nonzerostate) will be changed. If `B` is a device matrix, we need to somehow also update
3485:   `B`'s copy on device.  We do so by increasing `B`'s nonzerostate. In use of `B` on device, device matrix types should detect this change (ref. internal routines `MatSeqAIJCUSPARSECopyToGPU()` or
3486:   `MatAssemblyEnd_SeqAIJKokkos()`) and will just destroy and then recreate the device copy of `B`. It is not optimal, but is easy to implement and less hacky. To avoid this overhead, try to compute `garray`
3487:   yourself, see algorithms in the private function `MatSetUpMultiply_MPIAIJ()`.

3489:   The `NULL`-ness of `garray` doesn't need to be collective, in other words, `garray` can be `NULL` on some processes while not on others.

3491: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateMPIAIJWithSplitArrays()`
3492: @*/
3493: PetscErrorCode MatCreateMPIAIJWithSeqAIJ(MPI_Comm comm, PetscInt M, PetscInt N, Mat A, Mat B, PetscInt *garray, Mat *mat)
3494: {
3495:   PetscInt    m, n;
3496:   MatType     mpi_mat_type;
3497:   Mat_MPIAIJ *mpiaij;
3498:   Mat         C;

3500:   PetscFunctionBegin;
3501:   PetscCall(MatCreate(comm, &C));
3502:   PetscCall(MatGetSize(A, &m, &n));
3503:   PetscCheck(m == B->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Am %" PetscInt_FMT " != Bm %" PetscInt_FMT, m, B->rmap->N);
3504:   PetscCheck(A->rmap->bs == B->rmap->bs, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "A row bs %" PetscInt_FMT " != B row bs %" PetscInt_FMT, A->rmap->bs, B->rmap->bs);

3506:   PetscCall(MatSetSizes(C, m, n, M, N));
3507:   /* Determine the type of MPI matrix that should be created from the type of matrix A, which holds the "diagonal" portion. */
3508:   PetscCall(MatGetMPIMatType_Private(A, &mpi_mat_type));
3509:   PetscCall(MatSetType(C, mpi_mat_type));
3510:   if (!garray) {
3511:     const PetscScalar *ba;

3513:     B->nonzerostate++;
3514:     PetscCall(MatSeqAIJGetArrayRead(B, &ba)); /* Since we will destroy B's device copy, we need to make sure the host copy is up to date */
3515:     PetscCall(MatSeqAIJRestoreArrayRead(B, &ba));
3516:   }

3518:   PetscCall(MatSetBlockSizes(C, A->rmap->bs, A->cmap->bs));
3519:   PetscCall(PetscLayoutSetUp(C->rmap));
3520:   PetscCall(PetscLayoutSetUp(C->cmap));

3522:   mpiaij              = (Mat_MPIAIJ *)C->data;
3523:   mpiaij->A           = A;
3524:   mpiaij->B           = B;
3525:   mpiaij->garray      = garray;
3526:   C->preallocated     = PETSC_TRUE;
3527:   C->nooffprocentries = PETSC_TRUE; /* See MatAssemblyBegin_MPIAIJ. In effect, making MatAssemblyBegin a nop */

3529:   PetscCall(MatSetOption(C, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
3530:   PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
3531:   /* MatAssemblyEnd is critical here. It sets mat->offloadmask according to A and B's, and
3532:    also gets mpiaij->B compacted (if garray is NULL), with its col ids and size reduced
3533:    */
3534:   PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
3535:   PetscCall(MatSetOption(C, MAT_NO_OFF_PROC_ENTRIES, PETSC_FALSE));
3536:   PetscCall(MatSetOption(C, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
3537:   *mat = C;
3538:   PetscFunctionReturn(PETSC_SUCCESS);
3539: }

3541: extern PetscErrorCode MatCreateSubMatrices_MPIAIJ_SingleIS_Local(Mat, PetscInt, const IS[], const IS[], MatReuse, PetscBool, Mat *);

3543: PetscErrorCode MatCreateSubMatrix_MPIAIJ_SameRowDist(Mat mat, IS isrow, IS iscol, IS iscol_local, MatReuse call, Mat *newmat)
3544: {
3545:   PetscInt        i, m, n, rstart, row, rend, nz, j, bs, cbs;
3546:   PetscInt       *ii, *jj, nlocal, *dlens, *olens, dlen, olen, jend, mglobal;
3547:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)mat->data;
3548:   Mat             M, Msub, B = a->B;
3549:   MatScalar      *aa;
3550:   Mat_SeqAIJ     *aij;
3551:   PetscInt       *garray = a->garray, *colsub, Ncols;
3552:   PetscInt        count, Bn = B->cmap->N, cstart = mat->cmap->rstart, cend = mat->cmap->rend;
3553:   IS              iscol_sub, iscmap;
3554:   const PetscInt *is_idx, *cmap;
3555:   PetscBool       allcolumns = PETSC_FALSE;
3556:   MPI_Comm        comm;

3558:   PetscFunctionBegin;
3559:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3560:   if (call == MAT_REUSE_MATRIX) {
3561:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_sub));
3562:     PetscCheck(iscol_sub, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "SubIScol passed in was not used before, cannot reuse");
3563:     PetscCall(ISGetLocalSize(iscol_sub, &count));

3565:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "Subcmap", (PetscObject *)&iscmap));
3566:     PetscCheck(iscmap, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Subcmap passed in was not used before, cannot reuse");

3568:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubMatrix", (PetscObject *)&Msub));
3569:     PetscCheck(Msub, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");

3571:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol_sub, MAT_REUSE_MATRIX, PETSC_FALSE, &Msub));

3573:   } else { /* call == MAT_INITIAL_MATRIX) */
3574:     PetscBool flg;

3576:     PetscCall(ISGetLocalSize(iscol, &n));
3577:     PetscCall(ISGetSize(iscol, &Ncols));

3579:     /* (1) iscol -> nonscalable iscol_local */
3580:     /* Check for special case: each processor gets entire matrix columns */
3581:     PetscCall(ISIdentity(iscol_local, &flg));
3582:     if (flg && n == mat->cmap->N) allcolumns = PETSC_TRUE;
3583:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &allcolumns, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));
3584:     if (allcolumns) {
3585:       iscol_sub = iscol_local;
3586:       PetscCall(PetscObjectReference((PetscObject)iscol_local));
3587:       PetscCall(ISCreateStride(PETSC_COMM_SELF, n, 0, 1, &iscmap));

3589:     } else {
3590:       /* (2) iscol_local -> iscol_sub and iscmap. Implementation below requires iscol_local be sorted, it can have duplicate indices */
3591:       PetscInt *idx, *cmap1, k;
3592:       PetscCall(PetscMalloc1(Ncols, &idx));
3593:       PetscCall(PetscMalloc1(Ncols, &cmap1));
3594:       PetscCall(ISGetIndices(iscol_local, &is_idx));
3595:       count = 0;
3596:       k     = 0;
3597:       for (i = 0; i < Ncols; i++) {
3598:         j = is_idx[i];
3599:         if (j >= cstart && j < cend) {
3600:           /* diagonal part of mat */
3601:           idx[count]     = j;
3602:           cmap1[count++] = i; /* column index in submat */
3603:         } else if (Bn) {
3604:           /* off-diagonal part of mat */
3605:           if (j == garray[k]) {
3606:             idx[count]     = j;
3607:             cmap1[count++] = i; /* column index in submat */
3608:           } else if (j > garray[k]) {
3609:             while (j > garray[k] && k < Bn - 1) k++;
3610:             if (j == garray[k]) {
3611:               idx[count]     = j;
3612:               cmap1[count++] = i; /* column index in submat */
3613:             }
3614:           }
3615:         }
3616:       }
3617:       PetscCall(ISRestoreIndices(iscol_local, &is_idx));

3619:       PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count, idx, PETSC_OWN_POINTER, &iscol_sub));
3620:       PetscCall(ISGetBlockSize(iscol, &cbs));
3621:       PetscCall(ISSetBlockSize(iscol_sub, cbs));

3623:       PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)iscol_local), count, cmap1, PETSC_OWN_POINTER, &iscmap));
3624:     }

3626:     /* (3) Create sequential Msub */
3627:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol_sub, MAT_INITIAL_MATRIX, allcolumns, &Msub));
3628:   }

3630:   PetscCall(ISGetLocalSize(iscol_sub, &count));
3631:   aij = (Mat_SeqAIJ *)Msub->data;
3632:   ii  = aij->i;
3633:   PetscCall(ISGetIndices(iscmap, &cmap));

3635:   /*
3636:       m - number of local rows
3637:       Ncols - number of columns (same on all processors)
3638:       rstart - first row in new global matrix generated
3639:   */
3640:   PetscCall(MatGetSize(Msub, &m, NULL));

3642:   if (call == MAT_INITIAL_MATRIX) {
3643:     /* (4) Create parallel newmat */
3644:     PetscMPIInt rank, size;
3645:     PetscInt    csize;

3647:     PetscCallMPI(MPI_Comm_size(comm, &size));
3648:     PetscCallMPI(MPI_Comm_rank(comm, &rank));

3650:     /*
3651:         Determine the number of non-zeros in the diagonal and off-diagonal
3652:         portions of the matrix in order to do correct preallocation
3653:     */

3655:     /* first get start and end of "diagonal" columns */
3656:     PetscCall(ISGetLocalSize(iscol, &csize));
3657:     if (csize == PETSC_DECIDE) {
3658:       PetscCall(ISGetSize(isrow, &mglobal));
3659:       if (mglobal == Ncols) { /* square matrix */
3660:         nlocal = m;
3661:       } else {
3662:         nlocal = Ncols / size + ((Ncols % size) > rank);
3663:       }
3664:     } else {
3665:       nlocal = csize;
3666:     }
3667:     PetscCallMPI(MPI_Scan(&nlocal, &rend, 1, MPIU_INT, MPI_SUM, comm));
3668:     rstart = rend - nlocal;
3669:     PetscCheck(rank != size - 1 || rend == Ncols, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Local column sizes %" PetscInt_FMT " do not add up to total number of columns %" PetscInt_FMT, rend, Ncols);

3671:     /* next, compute all the lengths */
3672:     jj = aij->j;
3673:     PetscCall(PetscMalloc1(2 * m + 1, &dlens));
3674:     olens = dlens + m;
3675:     for (i = 0; i < m; i++) {
3676:       jend = ii[i + 1] - ii[i];
3677:       olen = 0;
3678:       dlen = 0;
3679:       for (j = 0; j < jend; j++) {
3680:         if (cmap[*jj] < rstart || cmap[*jj] >= rend) olen++;
3681:         else dlen++;
3682:         jj++;
3683:       }
3684:       olens[i] = olen;
3685:       dlens[i] = dlen;
3686:     }

3688:     PetscCall(ISGetBlockSize(isrow, &bs));
3689:     PetscCall(ISGetBlockSize(iscol, &cbs));

3691:     PetscCall(MatCreate(comm, &M));
3692:     PetscCall(MatSetSizes(M, m, nlocal, PETSC_DECIDE, Ncols));
3693:     PetscCall(MatSetBlockSizes(M, bs, cbs));
3694:     PetscCall(MatSetType(M, ((PetscObject)mat)->type_name));
3695:     PetscCall(MatMPIAIJSetPreallocation(M, 0, dlens, 0, olens));
3696:     PetscCall(PetscFree(dlens));

3698:   } else { /* call == MAT_REUSE_MATRIX */
3699:     M = *newmat;
3700:     PetscCall(MatGetLocalSize(M, &i, NULL));
3701:     PetscCheck(i == m, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Previous matrix must be same size/layout as request");
3702:     PetscCall(MatZeroEntries(M));
3703:     /*
3704:          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3705:        rather than the slower MatSetValues().
3706:     */
3707:     M->was_assembled = PETSC_TRUE;
3708:     M->assembled     = PETSC_FALSE;
3709:   }

3711:   /* (5) Set values of Msub to *newmat */
3712:   PetscCall(PetscMalloc1(count, &colsub));
3713:   PetscCall(MatGetOwnershipRange(M, &rstart, NULL));

3715:   jj = aij->j;
3716:   PetscCall(MatSeqAIJGetArrayRead(Msub, (const PetscScalar **)&aa));
3717:   for (i = 0; i < m; i++) {
3718:     row = rstart + i;
3719:     nz  = ii[i + 1] - ii[i];
3720:     for (j = 0; j < nz; j++) colsub[j] = cmap[jj[j]];
3721:     PetscCall(MatSetValues_MPIAIJ(M, 1, &row, nz, colsub, aa, INSERT_VALUES));
3722:     jj += nz;
3723:     aa += nz;
3724:   }
3725:   PetscCall(MatSeqAIJRestoreArrayRead(Msub, (const PetscScalar **)&aa));
3726:   PetscCall(ISRestoreIndices(iscmap, &cmap));

3728:   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
3729:   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));

3731:   PetscCall(PetscFree(colsub));

3733:   /* save Msub, iscol_sub and iscmap used in processor for next request */
3734:   if (call == MAT_INITIAL_MATRIX) {
3735:     *newmat = M;
3736:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "SubMatrix", (PetscObject)Msub));
3737:     PetscCall(MatDestroy(&Msub));

3739:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "SubIScol", (PetscObject)iscol_sub));
3740:     PetscCall(ISDestroy(&iscol_sub));

3742:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "Subcmap", (PetscObject)iscmap));
3743:     PetscCall(ISDestroy(&iscmap));

3745:     if (iscol_local) {
3746:       PetscCall(PetscObjectCompose((PetscObject)*newmat, "ISAllGather", (PetscObject)iscol_local));
3747:       PetscCall(ISDestroy(&iscol_local));
3748:     }
3749:   }
3750:   PetscFunctionReturn(PETSC_SUCCESS);
3751: }

3753: /*
3754:     Not great since it makes two copies of the submatrix, first an SeqAIJ
3755:   in local and then by concatenating the local matrices the end result.
3756:   Writing it directly would be much like MatCreateSubMatrices_MPIAIJ()

3758:   This requires a sequential iscol with all indices.
3759: */
3760: PetscErrorCode MatCreateSubMatrix_MPIAIJ_nonscalable(Mat mat, IS isrow, IS iscol, PetscInt csize, MatReuse call, Mat *newmat)
3761: {
3762:   PetscMPIInt rank, size;
3763:   PetscInt    i, m, n, rstart, row, rend, nz, *cwork, j, bs, cbs;
3764:   PetscInt   *ii, *jj, nlocal, *dlens, *olens, dlen, olen, jend, mglobal;
3765:   Mat         M, Mreuse;
3766:   MatScalar  *aa, *vwork;
3767:   MPI_Comm    comm;
3768:   Mat_SeqAIJ *aij;
3769:   PetscBool   colflag, allcolumns = PETSC_FALSE;

3771:   PetscFunctionBegin;
3772:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3773:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
3774:   PetscCallMPI(MPI_Comm_size(comm, &size));

3776:   /* Check for special case: each processor gets entire matrix columns */
3777:   PetscCall(ISIdentity(iscol, &colflag));
3778:   PetscCall(ISGetLocalSize(iscol, &n));
3779:   if (colflag && n == mat->cmap->N) allcolumns = PETSC_TRUE;
3780:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &allcolumns, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));

3782:   if (call == MAT_REUSE_MATRIX) {
3783:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubMatrix", (PetscObject *)&Mreuse));
3784:     PetscCheck(Mreuse, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");
3785:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol, MAT_REUSE_MATRIX, allcolumns, &Mreuse));
3786:   } else {
3787:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol, MAT_INITIAL_MATRIX, allcolumns, &Mreuse));
3788:   }

3790:   /*
3791:       m - number of local rows
3792:       n - number of columns (same on all processors)
3793:       rstart - first row in new global matrix generated
3794:   */
3795:   PetscCall(MatGetSize(Mreuse, &m, &n));
3796:   PetscCall(MatGetBlockSizes(Mreuse, &bs, &cbs));
3797:   if (call == MAT_INITIAL_MATRIX) {
3798:     aij = (Mat_SeqAIJ *)Mreuse->data;
3799:     ii  = aij->i;
3800:     jj  = aij->j;

3802:     /*
3803:         Determine the number of non-zeros in the diagonal and off-diagonal
3804:         portions of the matrix in order to do correct preallocation
3805:     */

3807:     /* first get start and end of "diagonal" columns */
3808:     if (csize == PETSC_DECIDE) {
3809:       PetscCall(ISGetSize(isrow, &mglobal));
3810:       if (mglobal == n) { /* square matrix */
3811:         nlocal = m;
3812:       } else {
3813:         nlocal = n / size + ((n % size) > rank);
3814:       }
3815:     } else {
3816:       nlocal = csize;
3817:     }
3818:     PetscCallMPI(MPI_Scan(&nlocal, &rend, 1, MPIU_INT, MPI_SUM, comm));
3819:     rstart = rend - nlocal;
3820:     PetscCheck(rank != size - 1 || rend == n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Local column sizes %" PetscInt_FMT " do not add up to total number of columns %" PetscInt_FMT, rend, n);

3822:     /* next, compute all the lengths */
3823:     PetscCall(PetscMalloc1(2 * m + 1, &dlens));
3824:     olens = dlens + m;
3825:     for (i = 0; i < m; i++) {
3826:       jend = ii[i + 1] - ii[i];
3827:       olen = 0;
3828:       dlen = 0;
3829:       for (j = 0; j < jend; j++) {
3830:         if (*jj < rstart || *jj >= rend) olen++;
3831:         else dlen++;
3832:         jj++;
3833:       }
3834:       olens[i] = olen;
3835:       dlens[i] = dlen;
3836:     }
3837:     PetscCall(MatCreate(comm, &M));
3838:     PetscCall(MatSetSizes(M, m, nlocal, PETSC_DECIDE, n));
3839:     PetscCall(MatSetBlockSizes(M, bs, cbs));
3840:     PetscCall(MatSetType(M, ((PetscObject)mat)->type_name));
3841:     PetscCall(MatMPIAIJSetPreallocation(M, 0, dlens, 0, olens));
3842:     PetscCall(PetscFree(dlens));
3843:   } else {
3844:     PetscInt ml, nl;

3846:     M = *newmat;
3847:     PetscCall(MatGetLocalSize(M, &ml, &nl));
3848:     PetscCheck(ml == m, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Previous matrix must be same size/layout as request");
3849:     PetscCall(MatZeroEntries(M));
3850:     /*
3851:          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3852:        rather than the slower MatSetValues().
3853:     */
3854:     M->was_assembled = PETSC_TRUE;
3855:     M->assembled     = PETSC_FALSE;
3856:   }
3857:   PetscCall(MatGetOwnershipRange(M, &rstart, &rend));
3858:   aij = (Mat_SeqAIJ *)Mreuse->data;
3859:   ii  = aij->i;
3860:   jj  = aij->j;

3862:   /* trigger copy to CPU if needed */
3863:   PetscCall(MatSeqAIJGetArrayRead(Mreuse, (const PetscScalar **)&aa));
3864:   for (i = 0; i < m; i++) {
3865:     row   = rstart + i;
3866:     nz    = ii[i + 1] - ii[i];
3867:     cwork = jj;
3868:     jj    = PetscSafePointerPlusOffset(jj, nz);
3869:     vwork = aa;
3870:     aa    = PetscSafePointerPlusOffset(aa, nz);
3871:     PetscCall(MatSetValues_MPIAIJ(M, 1, &row, nz, cwork, vwork, INSERT_VALUES));
3872:   }
3873:   PetscCall(MatSeqAIJRestoreArrayRead(Mreuse, (const PetscScalar **)&aa));

3875:   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
3876:   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));
3877:   *newmat = M;

3879:   /* save submatrix used in processor for next request */
3880:   if (call == MAT_INITIAL_MATRIX) {
3881:     PetscCall(PetscObjectCompose((PetscObject)M, "SubMatrix", (PetscObject)Mreuse));
3882:     PetscCall(MatDestroy(&Mreuse));
3883:   }
3884:   PetscFunctionReturn(PETSC_SUCCESS);
3885: }

3887: static PetscErrorCode MatMPIAIJSetPreallocationCSR_MPIAIJ(Mat B, const PetscInt Ii[], const PetscInt J[], const PetscScalar v[])
3888: {
3889:   PetscInt        m, cstart, cend, j, nnz, i, d, *ld;
3890:   PetscInt       *d_nnz, *o_nnz, nnz_max = 0, rstart, ii, irstart;
3891:   const PetscInt *JJ;
3892:   PetscBool       nooffprocentries;
3893:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)B->data;

3895:   PetscFunctionBegin;
3896:   PetscCall(PetscLayoutSetUp(B->rmap));
3897:   PetscCall(PetscLayoutSetUp(B->cmap));
3898:   m       = B->rmap->n;
3899:   cstart  = B->cmap->rstart;
3900:   cend    = B->cmap->rend;
3901:   rstart  = B->rmap->rstart;
3902:   irstart = Ii[0];

3904:   PetscCall(PetscCalloc2(m, &d_nnz, m, &o_nnz));

3906:   if (PetscDefined(USE_DEBUG)) {
3907:     for (i = 0; i < m; i++) {
3908:       nnz = Ii[i + 1] - Ii[i];
3909:       JJ  = PetscSafePointerPlusOffset(J, Ii[i] - irstart);
3910:       PetscCheck(nnz >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Local row %" PetscInt_FMT " has a negative %" PetscInt_FMT " number of columns", i, nnz);
3911:       PetscCheck(!nnz || !(JJ[0] < 0), PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Row %" PetscInt_FMT " starts with negative column index %" PetscInt_FMT, i, JJ[0]);
3912:       PetscCheck(!nnz || !(JJ[nnz - 1] >= B->cmap->N), PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Row %" PetscInt_FMT " ends with too large a column index %" PetscInt_FMT " (max allowed %" PetscInt_FMT ")", i, JJ[nnz - 1], B->cmap->N);
3913:     }
3914:   }

3916:   for (i = 0; i < m; i++) {
3917:     nnz     = Ii[i + 1] - Ii[i];
3918:     JJ      = PetscSafePointerPlusOffset(J, Ii[i] - irstart);
3919:     nnz_max = PetscMax(nnz_max, nnz);
3920:     d       = 0;
3921:     for (j = 0; j < nnz; j++) {
3922:       if (cstart <= JJ[j] && JJ[j] < cend) d++;
3923:     }
3924:     d_nnz[i] = d;
3925:     o_nnz[i] = nnz - d;
3926:   }
3927:   PetscCall(MatMPIAIJSetPreallocation(B, 0, d_nnz, 0, o_nnz));
3928:   PetscCall(PetscFree2(d_nnz, o_nnz));

3930:   for (i = 0; i < m; i++) {
3931:     ii = i + rstart;
3932:     PetscCall(MatSetValues_MPIAIJ(B, 1, &ii, Ii[i + 1] - Ii[i], PetscSafePointerPlusOffset(J, Ii[i] - irstart), PetscSafePointerPlusOffset(v, Ii[i] - irstart), INSERT_VALUES));
3933:   }
3934:   nooffprocentries    = B->nooffprocentries;
3935:   B->nooffprocentries = PETSC_TRUE;
3936:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
3937:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
3938:   B->nooffprocentries = nooffprocentries;

3940:   /* count number of entries below block diagonal */
3941:   PetscCall(PetscFree(Aij->ld));
3942:   PetscCall(PetscCalloc1(m, &ld));
3943:   Aij->ld = ld;
3944:   for (i = 0; i < m; i++) {
3945:     nnz = Ii[i + 1] - Ii[i];
3946:     j   = 0;
3947:     while (j < nnz && J[j] < cstart) j++;
3948:     ld[i] = j;
3949:     if (J) J += nnz;
3950:   }

3952:   PetscCall(MatSetOption(B, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
3953:   PetscFunctionReturn(PETSC_SUCCESS);
3954: }

3956: /*@
3957:   MatMPIAIJSetPreallocationCSR - Allocates memory for a sparse parallel matrix in `MATAIJ` format
3958:   (the default parallel PETSc format).

3960:   Collective

3962:   Input Parameters:
3963: + B - the matrix
3964: . i - the indices into `j` for the start of each local row (indices start with zero)
3965: . j - the column indices for each local row (indices start with zero)
3966: - v - optional values in the matrix

3968:   Level: developer

3970:   Notes:
3971:   The `i`, `j`, and `v` arrays ARE copied by this routine into the internal format used by PETSc;
3972:   thus you CANNOT change the matrix entries by changing the values of `v` after you have
3973:   called this routine. Use `MatCreateMPIAIJWithSplitArrays()` to avoid needing to copy the arrays.

3975:   The `i` and `j` indices are 0 based, and `i` indices are indices corresponding to the local `j` array.

3977:   A convenience routine for this functionality is `MatCreateMPIAIJWithArrays()`.

3979:   You can update the matrix with new numerical values using `MatUpdateMPIAIJWithArrays()` after this call if the column indices in `j` are sorted.

3981:   If you do **not** use `MatUpdateMPIAIJWithArrays()`, the column indices in `j` do not need to be sorted. If you will use
3982:   `MatUpdateMPIAIJWithArrays()`, the column indices **must** be sorted.

3984:   The format which is used for the sparse matrix input, is equivalent to a
3985:   row-major ordering.. i.e for the following matrix, the input data expected is
3986:   as shown
3987: .vb
3988:         1 0 0
3989:         2 0 3     P0
3990:        -------
3991:         4 5 6     P1

3993:      Process0 [P0] rows_owned=[0,1]
3994:         i =  {0,1,3}  [size = nrow+1  = 2+1]
3995:         j =  {0,0,2}  [size = 3]
3996:         v =  {1,2,3}  [size = 3]

3998:      Process1 [P1] rows_owned=[2]
3999:         i =  {0,3}    [size = nrow+1  = 1+1]
4000:         j =  {0,1,2}  [size = 3]
4001:         v =  {4,5,6}  [size = 3]
4002: .ve

4004: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatCreateAIJ()`,
4005:           `MatCreateSeqAIJWithArrays()`, `MatCreateMPIAIJWithSplitArrays()`, `MatCreateMPIAIJWithArrays()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4006: @*/
4007: PetscErrorCode MatMPIAIJSetPreallocationCSR(Mat B, const PetscInt i[], const PetscInt j[], const PetscScalar v[])
4008: {
4009:   PetscFunctionBegin;
4010:   PetscTryMethod(B, "MatMPIAIJSetPreallocationCSR_C", (Mat, const PetscInt[], const PetscInt[], const PetscScalar[]), (B, i, j, v));
4011:   PetscFunctionReturn(PETSC_SUCCESS);
4012: }

4014: /*@
4015:   MatMPIAIJSetPreallocation - Preallocates memory for a sparse parallel matrix in `MATMPIAIJ` format
4016:   (the default parallel PETSc format).  For good matrix assembly performance
4017:   the user should preallocate the matrix storage by setting the parameters
4018:   `d_nz` (or `d_nnz`) and `o_nz` (or `o_nnz`).

4020:   Collective

4022:   Input Parameters:
4023: + B     - the matrix
4024: . d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4025:            (same value is used for all local rows)
4026: . d_nnz - array containing the number of nonzeros in the various rows of the
4027:            DIAGONAL portion of the local submatrix (possibly different for each row)
4028:            or `NULL` (`PETSC_NULL_INTEGER` in Fortran), if `d_nz` is used to specify the nonzero structure.
4029:            The size of this array is equal to the number of local rows, i.e 'm'.
4030:            For matrices that will be factored, you must leave room for (and set)
4031:            the diagonal entry even if it is zero.
4032: . o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4033:            submatrix (same value is used for all local rows).
4034: - o_nnz - array containing the number of nonzeros in the various rows of the
4035:            OFF-DIAGONAL portion of the local submatrix (possibly different for
4036:            each row) or `NULL` (`PETSC_NULL_INTEGER` in Fortran), if `o_nz` is used to specify the nonzero
4037:            structure. The size of this array is equal to the number
4038:            of local rows, i.e 'm'.

4040:   Example Usage:
4041:   Consider the following 8x8 matrix with 34 non-zero values, that is
4042:   assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4043:   proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4044:   as follows

4046: .vb
4047:             1  2  0  |  0  3  0  |  0  4
4048:     Proc0   0  5  6  |  7  0  0  |  8  0
4049:             9  0 10  | 11  0  0  | 12  0
4050:     -------------------------------------
4051:            13  0 14  | 15 16 17  |  0  0
4052:     Proc1   0 18  0  | 19 20 21  |  0  0
4053:             0  0  0  | 22 23  0  | 24  0
4054:     -------------------------------------
4055:     Proc2  25 26 27  |  0  0 28  | 29  0
4056:            30  0  0  | 31 32 33  |  0 34
4057: .ve

4059:   This can be represented as a collection of submatrices as
4060: .vb
4061:       A B C
4062:       D E F
4063:       G H I
4064: .ve

4066:   Where the submatrices A,B,C are owned by proc0, D,E,F are
4067:   owned by proc1, G,H,I are owned by proc2.

4069:   The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4070:   The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4071:   The 'M','N' parameters are 8,8, and have the same values on all procs.

4073:   The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4074:   submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4075:   corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4076:   Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4077:   part as `MATSEQAIJ` matrices. For example, proc1 will store [E] as a `MATSEQAIJ`
4078:   matrix, and [DF] as another `MATSEQAIJ` matrix.

4080:   When `d_nz`, `o_nz` parameters are specified, `d_nz` storage elements are
4081:   allocated for every row of the local DIAGONAL submatrix, and `o_nz`
4082:   storage locations are allocated for every row of the OFF-DIAGONAL submatrix.
4083:   One way to choose `d_nz` and `o_nz` is to use the maximum number of nonzeros over
4084:   the local rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4085:   In this case, the values of `d_nz`, `o_nz` are
4086: .vb
4087:      proc0  dnz = 2, o_nz = 2
4088:      proc1  dnz = 3, o_nz = 2
4089:      proc2  dnz = 1, o_nz = 4
4090: .ve
4091:   We are allocating `m`*(`d_nz`+`o_nz`) storage locations for every proc. This
4092:   translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4093:   for proc3. i.e we are using 12+15+10=37 storage locations to store
4094:   34 values.

4096:   When `d_nnz`, `o_nnz` parameters are specified, the storage is specified
4097:   for every row, corresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4098:   In the above case the values for `d_nnz`, `o_nnz` are
4099: .vb
4100:      proc0 d_nnz = [2,2,2] and o_nnz = [2,2,2]
4101:      proc1 d_nnz = [3,3,2] and o_nnz = [2,1,1]
4102:      proc2 d_nnz = [1,1]   and o_nnz = [4,4]
4103: .ve
4104:   Here the space allocated is sum of all the above values i.e 34, and
4105:   hence pre-allocation is perfect.

4107:   Level: intermediate

4109:   Notes:
4110:   If the *_nnz parameter is given then the *_nz parameter is ignored

4112:   The `MATAIJ` format, also called compressed row storage (CSR), is compatible with standard Fortran
4113:   storage.  The stored row and column indices begin with zero.
4114:   See [Sparse Matrices](sec_matsparse) for details.

4116:   The parallel matrix is partitioned such that the first m0 rows belong to
4117:   process 0, the next m1 rows belong to process 1, the next m2 rows belong
4118:   to process 2 etc.. where m0,m1,m2... are the input parameter 'm'.

4120:   The DIAGONAL portion of the local submatrix of a processor can be defined
4121:   as the submatrix which is obtained by extraction the part corresponding to
4122:   the rows r1-r2 and columns c1-c2 of the global matrix, where r1 is the
4123:   first row that belongs to the processor, r2 is the last row belonging to
4124:   the this processor, and c1-c2 is range of indices of the local part of a
4125:   vector suitable for applying the matrix to.  This is an mxn matrix.  In the
4126:   common case of a square matrix, the row and column ranges are the same and
4127:   the DIAGONAL part is also square. The remaining portion of the local
4128:   submatrix (mxN) constitute the OFF-DIAGONAL portion.

4130:   If `o_nnz` and `d_nnz` are specified, then `o_nz` and `d_nz` are ignored.

4132:   You can call `MatGetInfo()` to get information on how effective the preallocation was;
4133:   for example the fields mallocs,nz_allocated,nz_used,nz_unneeded;
4134:   You can also run with the option `-info` and look for messages with the string
4135:   malloc in them to see if additional memory allocation was needed.

4137: .seealso: [](ch_matrices), `Mat`, [Sparse Matrices](sec_matsparse), `MATMPIAIJ`, `MATAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatCreateAIJ()`, `MatMPIAIJSetPreallocationCSR()`,
4138:           `MatGetInfo()`, `PetscSplitOwnership()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4139: @*/
4140: PetscErrorCode MatMPIAIJSetPreallocation(Mat B, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[])
4141: {
4142:   PetscFunctionBegin;
4145:   PetscTryMethod(B, "MatMPIAIJSetPreallocation_C", (Mat, PetscInt, const PetscInt[], PetscInt, const PetscInt[]), (B, d_nz, d_nnz, o_nz, o_nnz));
4146:   PetscFunctionReturn(PETSC_SUCCESS);
4147: }

4149: /*@
4150:   MatCreateMPIAIJWithArrays - creates a `MATMPIAIJ` matrix using arrays that contain in standard
4151:   CSR format for the local rows.

4153:   Collective

4155:   Input Parameters:
4156: + comm - MPI communicator
4157: . m    - number of local rows (Cannot be `PETSC_DECIDE`)
4158: . n    - This value should be the same as the local size used in creating the
4159:          x vector for the matrix-vector product $ y = Ax$. (or `PETSC_DECIDE` to have
4160:          calculated if `N` is given) For square matrices n is almost always `m`.
4161: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if `m` is given)
4162: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if `n` is given)
4163: . i    - row indices (of length m+1); that is i[0] = 0, i[row] = i[row-1] + number of elements in that row of the matrix
4164: . j    - global column indices
4165: - a    - optional matrix values

4167:   Output Parameter:
4168: . mat - the matrix

4170:   Level: intermediate

4172:   Notes:
4173:   The `i`, `j`, and `a` arrays ARE copied by this routine into the internal format used by PETSc;
4174:   thus you CANNOT change the matrix entries by changing the values of `a[]` after you have
4175:   called this routine. Use `MatCreateMPIAIJWithSplitArrays()` to avoid needing to copy the arrays.

4177:   The `i` and `j` indices are 0 based, and `i` indices are indices corresponding to the local `j` array.

4179:   Once you have created the matrix you can update it with new numerical values using `MatUpdateMPIAIJWithArray()`

4181:   If you do **not** use `MatUpdateMPIAIJWithArray()`, the column indices in `j` do not need to be sorted. If you will use
4182:   `MatUpdateMPIAIJWithArrays()`, the column indices **must** be sorted.

4184:   The format which is used for the sparse matrix input, is equivalent to a
4185:   row-major ordering, i.e., for the following matrix, the input data expected is
4186:   as shown
4187: .vb
4188:         1 0 0
4189:         2 0 3     P0
4190:        -------
4191:         4 5 6     P1

4193:      Process0 [P0] rows_owned=[0,1]
4194:         i =  {0,1,3}  [size = nrow+1  = 2+1]
4195:         j =  {0,0,2}  [size = 3]
4196:         v =  {1,2,3}  [size = 3]

4198:      Process1 [P1] rows_owned=[2]
4199:         i =  {0,3}    [size = nrow+1  = 1+1]
4200:         j =  {0,1,2}  [size = 3]
4201:         v =  {4,5,6}  [size = 3]
4202: .ve

4204: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4205:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArray()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4206: @*/
4207: PetscErrorCode MatCreateMPIAIJWithArrays(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt M, PetscInt N, const PetscInt i[], const PetscInt j[], const PetscScalar a[], Mat *mat)
4208: {
4209:   PetscFunctionBegin;
4210:   PetscCheck(!i || !i[0], PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
4211:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
4212:   PetscCall(MatCreate(comm, mat));
4213:   PetscCall(MatSetSizes(*mat, m, n, M, N));
4214:   /* PetscCall(MatSetBlockSizes(M,bs,cbs)); */
4215:   PetscCall(MatSetType(*mat, MATMPIAIJ));
4216:   PetscCall(MatMPIAIJSetPreallocationCSR(*mat, i, j, a));
4217:   PetscFunctionReturn(PETSC_SUCCESS);
4218: }

4220: /*@
4221:   MatUpdateMPIAIJWithArrays - updates a `MATMPIAIJ` matrix using arrays that contain in standard
4222:   CSR format for the local rows. Only the numerical values are updated the other arrays must be identical to what was passed
4223:   from `MatCreateMPIAIJWithArrays()`

4225:   Deprecated: Use `MatUpdateMPIAIJWithArray()`

4227:   Collective

4229:   Input Parameters:
4230: + mat - the matrix
4231: . m   - number of local rows (Cannot be `PETSC_DECIDE`)
4232: . n   - This value should be the same as the local size used in creating the
4233:        x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4234:        calculated if N is given) For square matrices n is almost always m.
4235: . M   - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4236: . N   - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4237: . Ii  - row indices; that is Ii[0] = 0, Ii[row] = Ii[row-1] + number of elements in that row of the matrix
4238: . J   - column indices
4239: - v   - matrix values

4241:   Level: deprecated

4243: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4244:           `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArray()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4245: @*/
4246: PetscErrorCode MatUpdateMPIAIJWithArrays(Mat mat, PetscInt m, PetscInt n, PetscInt M, PetscInt N, const PetscInt Ii[], const PetscInt J[], const PetscScalar v[])
4247: {
4248:   PetscInt        nnz, i;
4249:   PetscBool       nooffprocentries;
4250:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)mat->data;
4251:   Mat_SeqAIJ     *Ad  = (Mat_SeqAIJ *)Aij->A->data;
4252:   PetscScalar    *ad, *ao;
4253:   PetscInt        ldi, Iii, md;
4254:   const PetscInt *Adi = Ad->i;
4255:   PetscInt       *ld  = Aij->ld;

4257:   PetscFunctionBegin;
4258:   PetscCheck(Ii[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
4259:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
4260:   PetscCheck(m == mat->rmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Local number of rows cannot change from call to MatUpdateMPIAIJWithArrays()");
4261:   PetscCheck(n == mat->cmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Local number of columns cannot change from call to MatUpdateMPIAIJWithArrays()");

4263:   PetscCall(MatSeqAIJGetArrayWrite(Aij->A, &ad));
4264:   PetscCall(MatSeqAIJGetArrayWrite(Aij->B, &ao));

4266:   for (i = 0; i < m; i++) {
4267:     if (PetscDefined(USE_DEBUG)) {
4268:       for (PetscInt j = Ii[i] + 1; j < Ii[i + 1]; ++j) {
4269:         PetscCheck(J[j] >= J[j - 1], PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column entry number %" PetscInt_FMT " (actual column %" PetscInt_FMT ") in row %" PetscInt_FMT " is not sorted", j - Ii[i], J[j], i);
4270:         PetscCheck(J[j] != J[j - 1], PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column entry number %" PetscInt_FMT " (actual column %" PetscInt_FMT ") in row %" PetscInt_FMT " is identical to previous entry", j - Ii[i], J[j], i);
4271:       }
4272:     }
4273:     nnz = Ii[i + 1] - Ii[i];
4274:     Iii = Ii[i];
4275:     ldi = ld[i];
4276:     md  = Adi[i + 1] - Adi[i];
4277:     PetscCall(PetscArraycpy(ao, v + Iii, ldi));
4278:     PetscCall(PetscArraycpy(ad, v + Iii + ldi, md));
4279:     PetscCall(PetscArraycpy(ao + ldi, v + Iii + ldi + md, nnz - ldi - md));
4280:     ad += md;
4281:     ao += nnz - md;
4282:   }
4283:   nooffprocentries      = mat->nooffprocentries;
4284:   mat->nooffprocentries = PETSC_TRUE;
4285:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->A, &ad));
4286:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->B, &ao));
4287:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->A));
4288:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->B));
4289:   PetscCall(PetscObjectStateIncrease((PetscObject)mat));
4290:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
4291:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
4292:   mat->nooffprocentries = nooffprocentries;
4293:   PetscFunctionReturn(PETSC_SUCCESS);
4294: }

4296: /*@
4297:   MatUpdateMPIAIJWithArray - updates an `MATMPIAIJ` matrix using an array that contains the nonzero values

4299:   Collective

4301:   Input Parameters:
4302: + mat - the matrix
4303: - v   - matrix values, stored by row

4305:   Level: intermediate

4307:   Notes:
4308:   The matrix must have been obtained with `MatCreateMPIAIJWithArrays()` or `MatMPIAIJSetPreallocationCSR()`

4310:   The column indices in the call to `MatCreateMPIAIJWithArrays()` or `MatMPIAIJSetPreallocationCSR()` must have been sorted for this call to work correctly

4312: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4313:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArrays()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4314: @*/
4315: PetscErrorCode MatUpdateMPIAIJWithArray(Mat mat, const PetscScalar v[])
4316: {
4317:   PetscInt        nnz, i, m;
4318:   PetscBool       nooffprocentries;
4319:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)mat->data;
4320:   Mat_SeqAIJ     *Ad  = (Mat_SeqAIJ *)Aij->A->data;
4321:   Mat_SeqAIJ     *Ao  = (Mat_SeqAIJ *)Aij->B->data;
4322:   PetscScalar    *ad, *ao;
4323:   const PetscInt *Adi = Ad->i, *Adj = Ao->i;
4324:   PetscInt        ldi, Iii, md;
4325:   PetscInt       *ld = Aij->ld;

4327:   PetscFunctionBegin;
4328:   m = mat->rmap->n;

4330:   PetscCall(MatSeqAIJGetArrayWrite(Aij->A, &ad));
4331:   PetscCall(MatSeqAIJGetArrayWrite(Aij->B, &ao));
4332:   Iii = 0;
4333:   for (i = 0; i < m; i++) {
4334:     nnz = Adi[i + 1] - Adi[i] + Adj[i + 1] - Adj[i];
4335:     ldi = ld[i];
4336:     md  = Adi[i + 1] - Adi[i];
4337:     PetscCall(PetscArraycpy(ad, v + Iii + ldi, md));
4338:     ad += md;
4339:     if (ao) {
4340:       PetscCall(PetscArraycpy(ao, v + Iii, ldi));
4341:       PetscCall(PetscArraycpy(ao + ldi, v + Iii + ldi + md, nnz - ldi - md));
4342:       ao += nnz - md;
4343:     }
4344:     Iii += nnz;
4345:   }
4346:   nooffprocentries      = mat->nooffprocentries;
4347:   mat->nooffprocentries = PETSC_TRUE;
4348:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->A, &ad));
4349:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->B, &ao));
4350:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->A));
4351:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->B));
4352:   PetscCall(PetscObjectStateIncrease((PetscObject)mat));
4353:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
4354:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
4355:   mat->nooffprocentries = nooffprocentries;
4356:   PetscFunctionReturn(PETSC_SUCCESS);
4357: }

4359: /*@
4360:   MatCreateAIJ - Creates a sparse parallel matrix in `MATAIJ` format
4361:   (the default parallel PETSc format).  For good matrix assembly performance
4362:   the user should preallocate the matrix storage by setting the parameters
4363:   `d_nz` (or `d_nnz`) and `o_nz` (or `o_nnz`).

4365:   Collective

4367:   Input Parameters:
4368: + comm  - MPI communicator
4369: . m     - number of local rows (or `PETSC_DECIDE` to have calculated if M is given)
4370:           This value should be the same as the local size used in creating the
4371:           y vector for the matrix-vector product y = Ax.
4372: . n     - This value should be the same as the local size used in creating the
4373:           x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4374:           calculated if N is given) For square matrices n is almost always m.
4375: . M     - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4376: . N     - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4377: . d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4378:           (same value is used for all local rows)
4379: . d_nnz - array containing the number of nonzeros in the various rows of the
4380:           DIAGONAL portion of the local submatrix (possibly different for each row)
4381:           or `NULL`, if `d_nz` is used to specify the nonzero structure.
4382:           The size of this array is equal to the number of local rows, i.e 'm'.
4383: . o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4384:           submatrix (same value is used for all local rows).
4385: - o_nnz - array containing the number of nonzeros in the various rows of the
4386:           OFF-DIAGONAL portion of the local submatrix (possibly different for
4387:           each row) or `NULL`, if `o_nz` is used to specify the nonzero
4388:           structure. The size of this array is equal to the number
4389:           of local rows, i.e 'm'.

4391:   Output Parameter:
4392: . A - the matrix

4394:   Options Database Keys:
4395: + -mat_no_inode                   - Do not use inodes
4396: . -mat_inode_limit limit          - Sets inode limit (max limit=5)
4397: - -matmult_vecscatter_view viewer - View the vecscatter (i.e., communication pattern) used in `MatMult()` of sparse parallel matrices.
4398:                                     See viewer types in manual of `MatView()`. Of them, ascii_matlab, draw or binary cause the `VecScatter`
4399:                                     to be viewed as a matrix. Entry (i,j) is the size of message (in bytes) rank i sends to rank j in one `MatMult()` call.

4401:   Level: intermediate

4403:   Notes:
4404:   It is recommended that one use `MatCreateFromOptions()` or the `MatCreate()`, `MatSetType()` and/or `MatSetFromOptions()`,
4405:   MatXXXXSetPreallocation() paradigm instead of this routine directly.
4406:   [MatXXXXSetPreallocation() is, for example, `MatSeqAIJSetPreallocation()`]

4408:   If the *_nnz parameter is given then the *_nz parameter is ignored

4410:   The `m`,`n`,`M`,`N` parameters specify the size of the matrix, and its partitioning across
4411:   processors, while `d_nz`,`d_nnz`,`o_nz`,`o_nnz` parameters specify the approximate
4412:   storage requirements for this matrix.

4414:   If `PETSC_DECIDE` or  `PETSC_DETERMINE` is used for a particular argument on one
4415:   processor than it must be used on all processors that share the object for
4416:   that argument.

4418:   If `m` and `n` are not `PETSC_DECIDE`, then the values determine the `PetscLayout` of the matrix and the ranges returned by
4419:   `MatGetOwnershipRange()`, `MatGetOwnershipRanges()`, `MatGetOwnershipRangeColumn()`, and `MatGetOwnershipRangesColumn()`.

4421:   The user MUST specify either the local or global matrix dimensions
4422:   (possibly both).

4424:   The parallel matrix is partitioned across processors such that the
4425:   first `m0` rows belong to process 0, the next `m1` rows belong to
4426:   process 1, the next `m2` rows belong to process 2, etc., where
4427:   `m0`, `m1`, `m2`... are the input parameter `m` on each MPI process. I.e., each MPI process stores
4428:   values corresponding to [m x N] submatrix.

4430:   The columns are logically partitioned with the n0 columns belonging
4431:   to 0th partition, the next n1 columns belonging to the next
4432:   partition etc.. where n0,n1,n2... are the input parameter 'n'.

4434:   The DIAGONAL portion of the local submatrix on any given processor
4435:   is the submatrix corresponding to the rows and columns m,n
4436:   corresponding to the given processor. i.e diagonal matrix on
4437:   process 0 is [m0 x n0], diagonal matrix on process 1 is [m1 x n1]
4438:   etc. The remaining portion of the local submatrix [m x (N-n)]
4439:   constitute the OFF-DIAGONAL portion. The example below better
4440:   illustrates this concept. The two matrices, the DIAGONAL portion and
4441:   the OFF-DIAGONAL portion are each stored as `MATSEQAIJ` matrices.

4443:   For a square global matrix we define each processor's diagonal portion
4444:   to be its local rows and the corresponding columns (a square submatrix);
4445:   each processor's off-diagonal portion encompasses the remainder of the
4446:   local matrix (a rectangular submatrix).

4448:   If `o_nnz`, `d_nnz` are specified, then `o_nz`, and `d_nz` are ignored.

4450:   When calling this routine with a single process communicator, a matrix of
4451:   type `MATSEQAIJ` is returned.  If a matrix of type `MATMPIAIJ` is desired for this
4452:   type of communicator, use the construction mechanism
4453: .vb
4454:   MatCreate(..., &A);
4455:   MatSetType(A, MATMPIAIJ);
4456:   MatSetSizes(A, m, n, M, N);
4457:   MatMPIAIJSetPreallocation(A, ...);
4458: .ve

4460:   By default, this format uses inodes (identical nodes) when possible.
4461:   We search for consecutive rows with the same nonzero structure, thereby
4462:   reusing matrix information to achieve increased efficiency.

4464:   Example Usage:
4465:   Consider the following 8x8 matrix with 34 non-zero values, that is
4466:   assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4467:   proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4468:   as follows

4470: .vb
4471:             1  2  0  |  0  3  0  |  0  4
4472:     Proc0   0  5  6  |  7  0  0  |  8  0
4473:             9  0 10  | 11  0  0  | 12  0
4474:     -------------------------------------
4475:            13  0 14  | 15 16 17  |  0  0
4476:     Proc1   0 18  0  | 19 20 21  |  0  0
4477:             0  0  0  | 22 23  0  | 24  0
4478:     -------------------------------------
4479:     Proc2  25 26 27  |  0  0 28  | 29  0
4480:            30  0  0  | 31 32 33  |  0 34
4481: .ve

4483:   This can be represented as a collection of submatrices as

4485: .vb
4486:       A B C
4487:       D E F
4488:       G H I
4489: .ve

4491:   Where the submatrices A,B,C are owned by proc0, D,E,F are
4492:   owned by proc1, G,H,I are owned by proc2.

4494:   The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4495:   The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4496:   The 'M','N' parameters are 8,8, and have the same values on all procs.

4498:   The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4499:   submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4500:   corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4501:   Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4502:   part as `MATSEQAIJ` matrices. For example, proc1 will store [E] as a `MATSEQAIJ`
4503:   matrix, and [DF] as another SeqAIJ matrix.

4505:   When `d_nz`, `o_nz` parameters are specified, `d_nz` storage elements are
4506:   allocated for every row of the local DIAGONAL submatrix, and `o_nz`
4507:   storage locations are allocated for every row of the OFF-DIAGONAL submatrix.
4508:   One way to choose `d_nz` and `o_nz` is to use the maximum number of nonzeros over
4509:   the local rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4510:   In this case, the values of `d_nz`,`o_nz` are
4511: .vb
4512:      proc0  dnz = 2, o_nz = 2
4513:      proc1  dnz = 3, o_nz = 2
4514:      proc2  dnz = 1, o_nz = 4
4515: .ve
4516:   We are allocating m*(`d_nz`+`o_nz`) storage locations for every proc. This
4517:   translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4518:   for proc3. i.e we are using 12+15+10=37 storage locations to store
4519:   34 values.

4521:   When `d_nnz`, `o_nnz` parameters are specified, the storage is specified
4522:   for every row, corresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4523:   In the above case the values for d_nnz,o_nnz are
4524: .vb
4525:      proc0 d_nnz = [2,2,2] and o_nnz = [2,2,2]
4526:      proc1 d_nnz = [3,3,2] and o_nnz = [2,1,1]
4527:      proc2 d_nnz = [1,1]   and o_nnz = [4,4]
4528: .ve
4529:   Here the space allocated is sum of all the above values i.e 34, and
4530:   hence pre-allocation is perfect.

4532: .seealso: [](ch_matrices), `Mat`, [Sparse Matrix Creation](sec_matsparse), `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4533:           `MATMPIAIJ`, `MatCreateMPIAIJWithArrays()`, `MatGetOwnershipRange()`, `MatGetOwnershipRanges()`, `MatGetOwnershipRangeColumn()`,
4534:           `MatGetOwnershipRangesColumn()`, `PetscLayout`
4535: @*/
4536: PetscErrorCode MatCreateAIJ(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt M, PetscInt N, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[], Mat *A)
4537: {
4538:   PetscMPIInt size;

4540:   PetscFunctionBegin;
4541:   PetscCall(MatCreate(comm, A));
4542:   PetscCall(MatSetSizes(*A, m, n, M, N));
4543:   PetscCallMPI(MPI_Comm_size(comm, &size));
4544:   if (size > 1) {
4545:     PetscCall(MatSetType(*A, MATMPIAIJ));
4546:     PetscCall(MatMPIAIJSetPreallocation(*A, d_nz, d_nnz, o_nz, o_nnz));
4547:   } else {
4548:     PetscCall(MatSetType(*A, MATSEQAIJ));
4549:     PetscCall(MatSeqAIJSetPreallocation(*A, d_nz, d_nnz));
4550:   }
4551:   PetscFunctionReturn(PETSC_SUCCESS);
4552: }

4554: /*@C
4555:   MatMPIAIJGetSeqAIJ - Returns the local pieces of this distributed matrix

4557:   Not Collective

4559:   Input Parameter:
4560: . A - The `MATMPIAIJ` matrix

4562:   Output Parameters:
4563: + Ad     - The local diagonal block as a `MATSEQAIJ` matrix
4564: . Ao     - The local off-diagonal block as a `MATSEQAIJ` matrix
4565: - colmap - An array mapping local column numbers of `Ao` to global column numbers of the parallel matrix

4567:   Level: intermediate

4569:   Note:
4570:   The rows in `Ad` and `Ao` are in [0, Nr), where Nr is the number of local rows on this process. The columns
4571:   in `Ad` are in [0, Nc) where Nc is the number of local columns. The columns are `Ao` are in [0, Nco), where Nco is
4572:   the number of nonzero columns in the local off-diagonal piece of the matrix `A`. The array colmap maps these
4573:   local column numbers to global column numbers in the original matrix.

4575: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatMPIAIJGetLocalMat()`, `MatMPIAIJGetLocalMatCondensed()`, `MatCreateAIJ()`, `MATSEQAIJ`
4576: @*/
4577: PetscErrorCode MatMPIAIJGetSeqAIJ(Mat A, Mat *Ad, Mat *Ao, const PetscInt *colmap[])
4578: {
4579:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
4580:   PetscBool   flg;

4582:   PetscFunctionBegin;
4583:   PetscCall(PetscStrbeginswith(((PetscObject)A)->type_name, MATMPIAIJ, &flg));
4584:   PetscCheck(flg, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "This function requires a MATMPIAIJ matrix as input");
4585:   if (Ad) *Ad = a->A;
4586:   if (Ao) *Ao = a->B;
4587:   if (colmap) *colmap = a->garray;
4588:   PetscFunctionReturn(PETSC_SUCCESS);
4589: }

4591: static PetscErrorCode MatGetMultPetscSF_MPIAIJ(Mat A, PetscSF *sf)
4592: {
4593:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

4595:   PetscFunctionBegin;
4596:   *sf = a->Mvctx;
4597:   PetscFunctionReturn(PETSC_SUCCESS);
4598: }

4600: PetscErrorCode MatCreateMPIMatConcatenateSeqMat_MPIAIJ(MPI_Comm comm, Mat inmat, PetscInt n, MatReuse scall, Mat *outmat)
4601: {
4602:   PetscInt     m, N, i, rstart, nnz, Ii;
4603:   PetscInt    *indx;
4604:   PetscScalar *values;
4605:   MatType      rootType;

4607:   PetscFunctionBegin;
4608:   PetscCall(MatGetSize(inmat, &m, &N));
4609:   if (scall == MAT_INITIAL_MATRIX) { /* symbolic phase */
4610:     PetscInt *dnz, *onz, sum, bs, cbs;

4612:     if (n == PETSC_DECIDE) PetscCall(PetscSplitOwnership(comm, &n, &N));
4613:     /* Check sum(n) = N */
4614:     PetscCallMPI(MPIU_Allreduce(&n, &sum, 1, MPIU_INT, MPI_SUM, comm));
4615:     PetscCheck(sum == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Sum of local columns %" PetscInt_FMT " != global columns %" PetscInt_FMT, sum, N);

4617:     PetscCallMPI(MPI_Scan(&m, &rstart, 1, MPIU_INT, MPI_SUM, comm));
4618:     rstart -= m;

4620:     MatPreallocateBegin(comm, m, n, dnz, onz);
4621:     for (i = 0; i < m; i++) {
4622:       PetscCall(MatGetRow_SeqAIJ(inmat, i, &nnz, &indx, NULL));
4623:       PetscCall(MatPreallocateSet(i + rstart, nnz, indx, dnz, onz));
4624:       PetscCall(MatRestoreRow_SeqAIJ(inmat, i, &nnz, &indx, NULL));
4625:     }

4627:     PetscCall(MatCreate(comm, outmat));
4628:     PetscCall(MatSetSizes(*outmat, m, n, PETSC_DETERMINE, PETSC_DETERMINE));
4629:     PetscCall(MatGetBlockSizes(inmat, &bs, &cbs));
4630:     PetscCall(MatSetBlockSizes(*outmat, bs, cbs));
4631:     PetscCall(MatGetRootType_Private(inmat, &rootType));
4632:     PetscCall(MatSetType(*outmat, rootType));
4633:     PetscCall(MatSeqAIJSetPreallocation(*outmat, 0, dnz));
4634:     PetscCall(MatMPIAIJSetPreallocation(*outmat, 0, dnz, 0, onz));
4635:     MatPreallocateEnd(dnz, onz);
4636:     PetscCall(MatSetOption(*outmat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
4637:   }

4639:   /* numeric phase */
4640:   PetscCall(MatGetOwnershipRange(*outmat, &rstart, NULL));
4641:   for (i = 0; i < m; i++) {
4642:     PetscCall(MatGetRow_SeqAIJ(inmat, i, &nnz, &indx, &values));
4643:     Ii = i + rstart;
4644:     PetscCall(MatSetValues(*outmat, 1, &Ii, nnz, indx, values, INSERT_VALUES));
4645:     PetscCall(MatRestoreRow_SeqAIJ(inmat, i, &nnz, &indx, &values));
4646:   }
4647:   PetscCall(MatAssemblyBegin(*outmat, MAT_FINAL_ASSEMBLY));
4648:   PetscCall(MatAssemblyEnd(*outmat, MAT_FINAL_ASSEMBLY));
4649:   PetscFunctionReturn(PETSC_SUCCESS);
4650: }

4652: static PetscErrorCode MatMergeSeqsToMPIDestroy(PetscCtxRt data)
4653: {
4654:   MatMergeSeqsToMPI *merge = *(MatMergeSeqsToMPI **)data;

4656:   PetscFunctionBegin;
4657:   if (!merge) PetscFunctionReturn(PETSC_SUCCESS);
4658:   PetscCall(PetscFree(merge->id_r));
4659:   PetscCall(PetscFree(merge->len_s));
4660:   PetscCall(PetscFree(merge->len_r));
4661:   PetscCall(PetscFree(merge->bi));
4662:   PetscCall(PetscFree(merge->bj));
4663:   PetscCall(PetscFree(merge->buf_ri[0]));
4664:   PetscCall(PetscFree(merge->buf_ri));
4665:   PetscCall(PetscFree(merge->buf_rj[0]));
4666:   PetscCall(PetscFree(merge->buf_rj));
4667:   PetscCall(PetscFree(merge->coi));
4668:   PetscCall(PetscFree(merge->coj));
4669:   PetscCall(PetscFree(merge->owners_co));
4670:   PetscCall(PetscLayoutDestroy(&merge->rowmap));
4671:   PetscCall(PetscFree(merge));
4672:   PetscFunctionReturn(PETSC_SUCCESS);
4673: }

4675: #include <../src/mat/utils/freespace.h>
4676: #include <petscbt.h>

4678: /*@
4679:   MatCreateMPIAIJSumSeqAIJNumeric - Fill the numerical values of an `MATMPIAIJ` matrix previously created by
4680:   `MatCreateMPIAIJSumSeqAIJSymbolic()` by summing the local `MATSEQAIJ` contributions from each process.

4682:   Collective

4684:   Input Parameters:
4685: + seqmat - the local `MATSEQAIJ` contribution from this process
4686: - mpimat - the target `MATMPIAIJ` matrix created by `MatCreateMPIAIJSumSeqAIJSymbolic()`

4688:   Level: developer

4690: .seealso: `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateMPIAIJSumSeqAIJSymbolic()`, `MatCreateMPIAIJSumSeqAIJ()`
4691: @*/
4692: PetscErrorCode MatCreateMPIAIJSumSeqAIJNumeric(Mat seqmat, Mat mpimat)
4693: {
4694:   MPI_Comm           comm;
4695:   Mat_SeqAIJ        *a = (Mat_SeqAIJ *)seqmat->data;
4696:   PetscMPIInt        size, rank, taga, *len_s;
4697:   PetscInt           N = mpimat->cmap->N, i, j, *owners, *ai = a->i, *aj, m;
4698:   PetscMPIInt        proc, k;
4699:   PetscInt         **buf_ri, **buf_rj;
4700:   PetscInt           anzi, *bj_i, *bi, *bj, arow, bnzi, nextaj;
4701:   PetscInt           nrows, **buf_ri_k, **nextrow, **nextai;
4702:   MPI_Request       *s_waits, *r_waits;
4703:   MPI_Status        *status;
4704:   const MatScalar   *aa, *a_a;
4705:   MatScalar        **abuf_r, *ba_i;
4706:   MatMergeSeqsToMPI *merge;
4707:   PetscContainer     container;

4709:   PetscFunctionBegin;
4710:   PetscCall(PetscObjectGetComm((PetscObject)mpimat, &comm));
4711:   PetscCall(PetscLogEventBegin(MAT_Seqstompinum, seqmat, 0, 0, 0));

4713:   PetscCallMPI(MPI_Comm_size(comm, &size));
4714:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

4716:   PetscCall(PetscObjectQuery((PetscObject)mpimat, "MatMergeSeqsToMPI", (PetscObject *)&container));
4717:   PetscCheck(container, PetscObjectComm((PetscObject)mpimat), PETSC_ERR_PLIB, "Mat not created from MatCreateMPIAIJSumSeqAIJSymbolic");
4718:   PetscCall(PetscContainerGetPointer(container, &merge));
4719:   PetscCall(MatSeqAIJGetArrayRead(seqmat, &a_a));
4720:   aa = a_a;

4722:   bi     = merge->bi;
4723:   bj     = merge->bj;
4724:   buf_ri = merge->buf_ri;
4725:   buf_rj = merge->buf_rj;

4727:   PetscCall(PetscMalloc1(size, &status));
4728:   owners = merge->rowmap->range;
4729:   len_s  = merge->len_s;

4731:   /* send and recv matrix values */
4732:   PetscCall(PetscObjectGetNewTag((PetscObject)mpimat, &taga));
4733:   PetscCall(PetscPostIrecvScalar(comm, taga, merge->nrecv, merge->id_r, merge->len_r, &abuf_r, &r_waits));

4735:   PetscCall(PetscMalloc1(merge->nsend + 1, &s_waits));
4736:   for (proc = 0, k = 0; proc < size; proc++) {
4737:     if (!len_s[proc]) continue;
4738:     i = owners[proc];
4739:     PetscCallMPI(MPIU_Isend(aa + ai[i], len_s[proc], MPIU_MATSCALAR, proc, taga, comm, s_waits + k));
4740:     k++;
4741:   }

4743:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, r_waits, status));
4744:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, s_waits, status));
4745:   PetscCall(PetscFree(status));

4747:   PetscCall(PetscFree(s_waits));
4748:   PetscCall(PetscFree(r_waits));

4750:   /* insert mat values of mpimat */
4751:   PetscCall(PetscMalloc1(N, &ba_i));
4752:   PetscCall(PetscMalloc3(merge->nrecv, &buf_ri_k, merge->nrecv, &nextrow, merge->nrecv, &nextai));

4754:   for (k = 0; k < merge->nrecv; k++) {
4755:     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4756:     nrows       = *buf_ri_k[k];
4757:     nextrow[k]  = buf_ri_k[k] + 1;           /* next row number of k-th recved i-structure */
4758:     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* points to the next i-structure of k-th recved i-structure  */
4759:   }

4761:   /* set values of ba */
4762:   m = merge->rowmap->n;
4763:   for (i = 0; i < m; i++) {
4764:     arow = owners[rank] + i;
4765:     bj_i = bj + bi[i]; /* col indices of the i-th row of mpimat */
4766:     bnzi = bi[i + 1] - bi[i];
4767:     PetscCall(PetscArrayzero(ba_i, bnzi));

4769:     /* add local non-zero vals of this proc's seqmat into ba */
4770:     anzi   = ai[arow + 1] - ai[arow];
4771:     aj     = a->j + ai[arow];
4772:     aa     = a_a + ai[arow];
4773:     nextaj = 0;
4774:     for (j = 0; nextaj < anzi; j++) {
4775:       if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4776:         ba_i[j] += aa[nextaj++];
4777:       }
4778:     }

4780:     /* add received vals into ba */
4781:     for (k = 0; k < merge->nrecv; k++) { /* k-th received message */
4782:       /* i-th row */
4783:       if (i == *nextrow[k]) {
4784:         anzi   = *(nextai[k] + 1) - *nextai[k];
4785:         aj     = buf_rj[k] + *nextai[k];
4786:         aa     = abuf_r[k] + *nextai[k];
4787:         nextaj = 0;
4788:         for (j = 0; nextaj < anzi; j++) {
4789:           if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4790:             ba_i[j] += aa[nextaj++];
4791:           }
4792:         }
4793:         nextrow[k]++;
4794:         nextai[k]++;
4795:       }
4796:     }
4797:     PetscCall(MatSetValues(mpimat, 1, &arow, bnzi, bj_i, ba_i, INSERT_VALUES));
4798:   }
4799:   PetscCall(MatSeqAIJRestoreArrayRead(seqmat, &a_a));
4800:   PetscCall(MatAssemblyBegin(mpimat, MAT_FINAL_ASSEMBLY));
4801:   PetscCall(MatAssemblyEnd(mpimat, MAT_FINAL_ASSEMBLY));

4803:   PetscCall(PetscFree(abuf_r[0]));
4804:   PetscCall(PetscFree(abuf_r));
4805:   PetscCall(PetscFree(ba_i));
4806:   PetscCall(PetscFree3(buf_ri_k, nextrow, nextai));
4807:   PetscCall(PetscLogEventEnd(MAT_Seqstompinum, seqmat, 0, 0, 0));
4808:   PetscFunctionReturn(PETSC_SUCCESS);
4809: }

4811: /*@
4812:   MatCreateMPIAIJSumSeqAIJSymbolic - Create the symbolic (nonzero-pattern) portion of an `MATMPIAIJ` matrix
4813:   obtained by summing local `MATSEQAIJ` contributions from each process.

4815:   Collective

4817:   Input Parameters:
4818: + comm   - the communicator
4819: . seqmat - the local `MATSEQAIJ` contribution from this process
4820: . m      - the number of local rows for the resulting `MATMPIAIJ` matrix, or `PETSC_DECIDE`
4821: - n      - the number of local columns for the resulting `MATMPIAIJ` matrix, or `PETSC_DECIDE`

4823:   Output Parameter:
4824: . mpimat - the newly created `MATMPIAIJ` matrix

4826:   Level: developer

4828:   Note:
4829:   The numerical values are filled in by a subsequent call to `MatCreateMPIAIJSumSeqAIJNumeric()`.

4831: .seealso: `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateMPIAIJSumSeqAIJNumeric()`, `MatCreateMPIAIJSumSeqAIJ()`
4832: @*/
4833: PetscErrorCode MatCreateMPIAIJSumSeqAIJSymbolic(MPI_Comm comm, Mat seqmat, PetscInt m, PetscInt n, Mat *mpimat)
4834: {
4835:   Mat                B_mpi;
4836:   Mat_SeqAIJ        *a = (Mat_SeqAIJ *)seqmat->data;
4837:   PetscMPIInt        size, rank, tagi, tagj, *len_s, *len_si, *len_ri;
4838:   PetscInt         **buf_rj, **buf_ri, **buf_ri_k;
4839:   PetscInt           M = seqmat->rmap->n, N = seqmat->cmap->n, i, *owners, *ai = a->i, *aj = a->j;
4840:   PetscInt           len, *dnz, *onz, bs, cbs;
4841:   PetscInt           k, anzi, *bi, *bj, *lnk, nlnk, arow, bnzi;
4842:   PetscInt           nrows, *buf_s, *buf_si, *buf_si_i, **nextrow, **nextai;
4843:   MPI_Request       *si_waits, *sj_waits, *ri_waits, *rj_waits;
4844:   MPI_Status        *status;
4845:   PetscFreeSpaceList free_space = NULL, current_space = NULL;
4846:   PetscBT            lnkbt;
4847:   MatMergeSeqsToMPI *merge;
4848:   PetscContainer     container;

4850:   PetscFunctionBegin;
4851:   PetscCall(PetscLogEventBegin(MAT_Seqstompisym, seqmat, 0, 0, 0));

4853:   /* make sure it is a PETSc comm */
4854:   PetscCall(PetscCommDuplicate(comm, &comm, NULL));
4855:   PetscCallMPI(MPI_Comm_size(comm, &size));
4856:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

4858:   PetscCall(PetscNew(&merge));
4859:   PetscCall(PetscMalloc1(size, &status));

4861:   /* determine row ownership */
4862:   PetscCall(PetscLayoutCreate(comm, &merge->rowmap));
4863:   PetscCall(PetscLayoutSetLocalSize(merge->rowmap, m));
4864:   PetscCall(PetscLayoutSetSize(merge->rowmap, M));
4865:   PetscCall(PetscLayoutSetBlockSize(merge->rowmap, 1));
4866:   PetscCall(PetscLayoutSetUp(merge->rowmap));
4867:   PetscCall(PetscMalloc1(size, &len_si));
4868:   PetscCall(PetscMalloc1(size, &merge->len_s));

4870:   m      = merge->rowmap->n;
4871:   owners = merge->rowmap->range;

4873:   /* determine the number of messages to send, their lengths */
4874:   len_s = merge->len_s;

4876:   len          = 0; /* length of buf_si[] */
4877:   merge->nsend = 0;
4878:   for (PetscMPIInt proc = 0; proc < size; proc++) {
4879:     len_si[proc] = 0;
4880:     if (proc == rank) {
4881:       len_s[proc] = 0;
4882:     } else {
4883:       PetscCall(PetscMPIIntCast(owners[proc + 1] - owners[proc] + 1, &len_si[proc]));
4884:       PetscCall(PetscMPIIntCast(ai[owners[proc + 1]] - ai[owners[proc]], &len_s[proc])); /* num of rows to be sent to [proc] */
4885:     }
4886:     if (len_s[proc]) {
4887:       merge->nsend++;
4888:       nrows = 0;
4889:       for (i = owners[proc]; i < owners[proc + 1]; i++) {
4890:         if (ai[i + 1] > ai[i]) nrows++;
4891:       }
4892:       PetscCall(PetscMPIIntCast(2 * (nrows + 1), &len_si[proc]));
4893:       len += len_si[proc];
4894:     }
4895:   }

4897:   /* determine the number and length of messages to receive for ij-structure */
4898:   PetscCall(PetscGatherNumberOfMessages(comm, NULL, len_s, &merge->nrecv));
4899:   PetscCall(PetscGatherMessageLengths2(comm, merge->nsend, merge->nrecv, len_s, len_si, &merge->id_r, &merge->len_r, &len_ri));

4901:   /* post the Irecv of j-structure */
4902:   PetscCall(PetscCommGetNewTag(comm, &tagj));
4903:   PetscCall(PetscPostIrecvInt(comm, tagj, merge->nrecv, merge->id_r, merge->len_r, &buf_rj, &rj_waits));

4905:   /* post the Isend of j-structure */
4906:   PetscCall(PetscMalloc2(merge->nsend, &si_waits, merge->nsend, &sj_waits));

4908:   for (PetscMPIInt proc = 0, k = 0; proc < size; proc++) {
4909:     if (!len_s[proc]) continue;
4910:     i = owners[proc];
4911:     PetscCallMPI(MPIU_Isend(aj + ai[i], len_s[proc], MPIU_INT, proc, tagj, comm, sj_waits + k));
4912:     k++;
4913:   }

4915:   /* receives and sends of j-structure are complete */
4916:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, rj_waits, status));
4917:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, sj_waits, status));

4919:   /* send and recv i-structure */
4920:   PetscCall(PetscCommGetNewTag(comm, &tagi));
4921:   PetscCall(PetscPostIrecvInt(comm, tagi, merge->nrecv, merge->id_r, len_ri, &buf_ri, &ri_waits));

4923:   PetscCall(PetscMalloc1(len + 1, &buf_s));
4924:   buf_si = buf_s; /* points to the beginning of k-th msg to be sent */
4925:   for (PetscMPIInt proc = 0, k = 0; proc < size; proc++) {
4926:     if (!len_s[proc]) continue;
4927:     /* form outgoing message for i-structure:
4928:          buf_si[0]:                 nrows to be sent
4929:                [1:nrows]:           row index (global)
4930:                [nrows+1:2*nrows+1]: i-structure index
4931:     */
4932:     nrows       = len_si[proc] / 2 - 1;
4933:     buf_si_i    = buf_si + nrows + 1;
4934:     buf_si[0]   = nrows;
4935:     buf_si_i[0] = 0;
4936:     nrows       = 0;
4937:     for (i = owners[proc]; i < owners[proc + 1]; i++) {
4938:       anzi = ai[i + 1] - ai[i];
4939:       if (anzi) {
4940:         buf_si_i[nrows + 1] = buf_si_i[nrows] + anzi; /* i-structure */
4941:         buf_si[nrows + 1]   = i - owners[proc];       /* local row index */
4942:         nrows++;
4943:       }
4944:     }
4945:     PetscCallMPI(MPIU_Isend(buf_si, len_si[proc], MPIU_INT, proc, tagi, comm, si_waits + k));
4946:     k++;
4947:     buf_si += len_si[proc];
4948:   }

4950:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, ri_waits, status));
4951:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, si_waits, status));

4953:   PetscCall(PetscInfo(seqmat, "nsend: %d, nrecv: %d\n", merge->nsend, merge->nrecv));
4954:   for (i = 0; i < merge->nrecv; i++) PetscCall(PetscInfo(seqmat, "recv len_ri=%d, len_rj=%d from [%d]\n", len_ri[i], merge->len_r[i], merge->id_r[i]));

4956:   PetscCall(PetscFree(len_si));
4957:   PetscCall(PetscFree(len_ri));
4958:   PetscCall(PetscFree(rj_waits));
4959:   PetscCall(PetscFree2(si_waits, sj_waits));
4960:   PetscCall(PetscFree(ri_waits));
4961:   PetscCall(PetscFree(buf_s));
4962:   PetscCall(PetscFree(status));

4964:   /* compute a local seq matrix in each processor */
4965:   /* allocate bi array and free space for accumulating nonzero column info */
4966:   PetscCall(PetscMalloc1(m + 1, &bi));
4967:   bi[0] = 0;

4969:   /* create and initialize a linked list */
4970:   nlnk = N + 1;
4971:   PetscCall(PetscLLCreate(N, N, nlnk, lnk, lnkbt));

4973:   /* initial FreeSpace size is 2*(num of local nnz(seqmat)) */
4974:   len = ai[owners[rank + 1]] - ai[owners[rank]];
4975:   PetscCall(PetscFreeSpaceGet(PetscIntMultTruncate(2, len) + 1, &free_space));

4977:   current_space = free_space;

4979:   /* determine symbolic info for each local row */
4980:   PetscCall(PetscMalloc3(merge->nrecv, &buf_ri_k, merge->nrecv, &nextrow, merge->nrecv, &nextai));

4982:   for (k = 0; k < merge->nrecv; k++) {
4983:     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4984:     nrows       = *buf_ri_k[k];
4985:     nextrow[k]  = buf_ri_k[k] + 1;           /* next row number of k-th recved i-structure */
4986:     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* points to the next i-structure of k-th recved i-structure  */
4987:   }

4989:   MatPreallocateBegin(comm, m, n, dnz, onz);
4990:   len = 0;
4991:   for (i = 0; i < m; i++) {
4992:     bnzi = 0;
4993:     /* add local non-zero cols of this proc's seqmat into lnk */
4994:     arow = owners[rank] + i;
4995:     anzi = ai[arow + 1] - ai[arow];
4996:     aj   = a->j + ai[arow];
4997:     PetscCall(PetscLLAddSorted(anzi, aj, N, &nlnk, lnk, lnkbt));
4998:     bnzi += nlnk;
4999:     /* add received col data into lnk */
5000:     for (k = 0; k < merge->nrecv; k++) { /* k-th received message */
5001:       if (i == *nextrow[k]) {            /* i-th row */
5002:         anzi = *(nextai[k] + 1) - *nextai[k];
5003:         aj   = buf_rj[k] + *nextai[k];
5004:         PetscCall(PetscLLAddSorted(anzi, aj, N, &nlnk, lnk, lnkbt));
5005:         bnzi += nlnk;
5006:         nextrow[k]++;
5007:         nextai[k]++;
5008:       }
5009:     }
5010:     if (len < bnzi) len = bnzi; /* =max(bnzi) */

5012:     /* if free space is not available, make more free space */
5013:     if (current_space->local_remaining < bnzi) PetscCall(PetscFreeSpaceGet(PetscIntSumTruncate(bnzi, current_space->total_array_size), &current_space));
5014:     /* copy data into free space, then initialize lnk */
5015:     PetscCall(PetscLLClean(N, N, bnzi, lnk, current_space->array, lnkbt));
5016:     PetscCall(MatPreallocateSet(i + owners[rank], bnzi, current_space->array, dnz, onz));

5018:     current_space->array += bnzi;
5019:     current_space->local_used += bnzi;
5020:     current_space->local_remaining -= bnzi;

5022:     bi[i + 1] = bi[i] + bnzi;
5023:   }

5025:   PetscCall(PetscFree3(buf_ri_k, nextrow, nextai));

5027:   PetscCall(PetscMalloc1(bi[m], &bj));
5028:   PetscCall(PetscFreeSpaceContiguous(&free_space, bj));
5029:   PetscCall(PetscLLDestroy(lnk, lnkbt));

5031:   /* create symbolic parallel matrix B_mpi */
5032:   PetscCall(MatGetBlockSizes(seqmat, &bs, &cbs));
5033:   PetscCall(MatCreate(comm, &B_mpi));
5034:   if (n == PETSC_DECIDE) PetscCall(MatSetSizes(B_mpi, m, n, PETSC_DETERMINE, N));
5035:   else PetscCall(MatSetSizes(B_mpi, m, n, PETSC_DETERMINE, PETSC_DETERMINE));
5036:   PetscCall(MatSetBlockSizes(B_mpi, bs, cbs));
5037:   PetscCall(MatSetType(B_mpi, MATMPIAIJ));
5038:   PetscCall(MatMPIAIJSetPreallocation(B_mpi, 0, dnz, 0, onz));
5039:   MatPreallocateEnd(dnz, onz);
5040:   PetscCall(MatSetOption(B_mpi, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_FALSE));

5042:   /* B_mpi is not ready for use - assembly will be done by MatCreateMPIAIJSumSeqAIJNumeric() */
5043:   B_mpi->assembled = PETSC_FALSE;
5044:   merge->bi        = bi;
5045:   merge->bj        = bj;
5046:   merge->buf_ri    = buf_ri;
5047:   merge->buf_rj    = buf_rj;
5048:   merge->coi       = NULL;
5049:   merge->coj       = NULL;
5050:   merge->owners_co = NULL;

5052:   PetscCall(PetscCommDestroy(&comm));

5054:   /* attach the supporting struct to B_mpi for reuse */
5055:   PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &container));
5056:   PetscCall(PetscContainerSetPointer(container, merge));
5057:   PetscCall(PetscContainerSetCtxDestroy(container, MatMergeSeqsToMPIDestroy));
5058:   PetscCall(PetscObjectCompose((PetscObject)B_mpi, "MatMergeSeqsToMPI", (PetscObject)container));
5059:   PetscCall(PetscContainerDestroy(&container));
5060:   *mpimat = B_mpi;

5062:   PetscCall(PetscLogEventEnd(MAT_Seqstompisym, seqmat, 0, 0, 0));
5063:   PetscFunctionReturn(PETSC_SUCCESS);
5064: }

5066: /*@
5067:   MatCreateMPIAIJSumSeqAIJ - Creates a `MATMPIAIJ` matrix by adding sequential
5068:   matrices from each processor

5070:   Collective

5072:   Input Parameters:
5073: + comm   - the communicators the parallel matrix will live on
5074: . seqmat - the input sequential matrices
5075: . m      - number of local rows (or `PETSC_DECIDE`)
5076: . n      - number of local columns (or `PETSC_DECIDE`)
5077: - scall  - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5079:   Output Parameter:
5080: . mpimat - the parallel matrix generated

5082:   Level: advanced

5084:   Note:
5085:   The dimensions of the sequential matrix in each processor MUST be the same.
5086:   The input seqmat is included into the container `MatMergeSeqsToMPIDestroy`, and will be
5087:   destroyed when `mpimat` is destroyed. Call `PetscObjectQuery()` to access `seqmat`.

5089: .seealso: [](ch_matrices), `Mat`, `MatCreateAIJ()`
5090: @*/
5091: PetscErrorCode MatCreateMPIAIJSumSeqAIJ(MPI_Comm comm, Mat seqmat, PetscInt m, PetscInt n, MatReuse scall, Mat *mpimat)
5092: {
5093:   PetscMPIInt size;

5095:   PetscFunctionBegin;
5096:   PetscCallMPI(MPI_Comm_size(comm, &size));
5097:   if (size == 1) {
5098:     PetscCall(PetscLogEventBegin(MAT_Seqstompi, seqmat, 0, 0, 0));
5099:     if (scall == MAT_INITIAL_MATRIX) PetscCall(MatDuplicate(seqmat, MAT_COPY_VALUES, mpimat));
5100:     else PetscCall(MatCopy(seqmat, *mpimat, SAME_NONZERO_PATTERN));
5101:     PetscCall(PetscLogEventEnd(MAT_Seqstompi, seqmat, 0, 0, 0));
5102:     PetscFunctionReturn(PETSC_SUCCESS);
5103:   }
5104:   PetscCall(PetscLogEventBegin(MAT_Seqstompi, seqmat, 0, 0, 0));
5105:   if (scall == MAT_INITIAL_MATRIX) PetscCall(MatCreateMPIAIJSumSeqAIJSymbolic(comm, seqmat, m, n, mpimat));
5106:   PetscCall(MatCreateMPIAIJSumSeqAIJNumeric(seqmat, *mpimat));
5107:   PetscCall(PetscLogEventEnd(MAT_Seqstompi, seqmat, 0, 0, 0));
5108:   PetscFunctionReturn(PETSC_SUCCESS);
5109: }

5111: /*@
5112:   MatAIJGetLocalMat - Creates a `MATSEQAIJ` from a `MATAIJ` matrix.

5114:   Not Collective

5116:   Input Parameter:
5117: . A - the matrix

5119:   Output Parameter:
5120: . A_loc - the local sequential matrix generated

5122:   Level: developer

5124:   Notes:
5125:   The matrix is created by taking `A`'s local rows and putting them into a sequential matrix
5126:   with `mlocal` rows and `n` columns. Where `mlocal` is obtained with `MatGetLocalSize()` and
5127:   `n` is the global column count obtained with `MatGetSize()`

5129:   In other words combines the two parts of a parallel `MATMPIAIJ` matrix on each process to a single matrix.

5131:   For parallel matrices this creates an entirely new matrix. If the matrix is sequential it merely increases the reference count.

5133:   Destroy the matrix with `MatDestroy()`

5135: .seealso: [](ch_matrices), `Mat`, `MatMPIAIJGetLocalMat()`
5136: @*/
5137: PetscErrorCode MatAIJGetLocalMat(Mat A, Mat *A_loc)
5138: {
5139:   PetscBool mpi;

5141:   PetscFunctionBegin;
5142:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATMPIAIJ, &mpi));
5143:   if (mpi) PetscCall(MatMPIAIJGetLocalMat(A, MAT_INITIAL_MATRIX, A_loc));
5144:   else {
5145:     *A_loc = A;
5146:     PetscCall(PetscObjectReference((PetscObject)*A_loc));
5147:   }
5148:   PetscFunctionReturn(PETSC_SUCCESS);
5149: }

5151: /*@
5152:   MatMPIAIJGetLocalMat - Creates a `MATSEQAIJ` from a `MATMPIAIJ` matrix.

5154:   Not Collective

5156:   Input Parameters:
5157: + A     - the matrix
5158: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5160:   Output Parameter:
5161: . A_loc - the local sequential matrix generated

5163:   Level: developer

5165:   Notes:
5166:   The matrix is created by taking all `A`'s local rows and putting them into a sequential
5167:   matrix with `mlocal` rows and `n` columns.`mlocal` is the row count obtained with
5168:   `MatGetLocalSize()` and `n` is the global column count obtained with `MatGetSize()`.

5170:   In other words combines the two parts of a parallel `MATMPIAIJ` matrix on each process to a single matrix.

5172:   When `A` is sequential and `MAT_INITIAL_MATRIX` is requested, the matrix returned is the diagonal part of `A` (which contains the entire matrix),
5173:   with its reference count increased by one. Hence changing values of `A_loc` changes `A`. If `MAT_REUSE_MATRIX` is requested on a sequential matrix
5174:   then `MatCopy`(Adiag,*`A_loc`,`SAME_NONZERO_PATTERN`) is called to fill `A_loc`. Thus one can preallocate the appropriate sequential matrix `A_loc`
5175:   and then call this routine with `MAT_REUSE_MATRIX`. In this case, one can modify the values of `A_loc` without affecting the original sequential matrix.

5177: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMatCondensed()`, `MatMPIAIJGetLocalMatMerge()`
5178: @*/
5179: PetscErrorCode MatMPIAIJGetLocalMat(Mat A, MatReuse scall, Mat *A_loc)
5180: {
5181:   Mat_MPIAIJ        *mpimat = (Mat_MPIAIJ *)A->data;
5182:   Mat_SeqAIJ        *mat, *a, *b;
5183:   PetscInt          *ai, *aj, *bi, *bj, *cmap = mpimat->garray;
5184:   const PetscScalar *aa, *ba, *aav, *bav;
5185:   PetscScalar       *ca, *cam;
5186:   PetscMPIInt        size;
5187:   PetscInt           am = A->rmap->n, i, j, k, cstart = A->cmap->rstart;
5188:   PetscInt          *ci, *cj, col, ncols_d, ncols_o, jo;
5189:   PetscBool          match;

5191:   PetscFunctionBegin;
5192:   PetscCall(PetscStrbeginswith(((PetscObject)A)->type_name, MATMPIAIJ, &match));
5193:   PetscCheck(match, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Requires MATMPIAIJ matrix as input");
5194:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)A), &size));
5195:   if (size == 1) {
5196:     if (scall == MAT_INITIAL_MATRIX) {
5197:       PetscCall(PetscObjectReference((PetscObject)mpimat->A));
5198:       *A_loc = mpimat->A;
5199:     } else if (scall == MAT_REUSE_MATRIX) {
5200:       PetscCall(MatCopy(mpimat->A, *A_loc, SAME_NONZERO_PATTERN));
5201:     }
5202:     PetscFunctionReturn(PETSC_SUCCESS);
5203:   }

5205:   PetscCall(PetscLogEventBegin(MAT_Getlocalmat, A, 0, 0, 0));
5206:   a  = (Mat_SeqAIJ *)mpimat->A->data;
5207:   b  = (Mat_SeqAIJ *)mpimat->B->data;
5208:   ai = a->i;
5209:   aj = a->j;
5210:   bi = b->i;
5211:   bj = b->j;
5212:   PetscCall(MatSeqAIJGetArrayRead(mpimat->A, &aav));
5213:   PetscCall(MatSeqAIJGetArrayRead(mpimat->B, &bav));
5214:   aa = aav;
5215:   ba = bav;
5216:   if (scall == MAT_INITIAL_MATRIX) {
5217:     PetscCall(PetscMalloc1(1 + am, &ci));
5218:     ci[0] = 0;
5219:     for (i = 0; i < am; i++) ci[i + 1] = ci[i] + (ai[i + 1] - ai[i]) + (bi[i + 1] - bi[i]);
5220:     PetscCall(PetscMalloc1(1 + ci[am], &cj));
5221:     PetscCall(PetscMalloc1(1 + ci[am], &ca));
5222:     k = 0;
5223:     for (i = 0; i < am; i++) {
5224:       ncols_o = bi[i + 1] - bi[i];
5225:       ncols_d = ai[i + 1] - ai[i];
5226:       /* off-diagonal portion of A */
5227:       for (jo = 0; jo < ncols_o; jo++) {
5228:         col = cmap[*bj];
5229:         if (col >= cstart) break;
5230:         cj[k] = col;
5231:         bj++;
5232:         ca[k++] = *ba++;
5233:       }
5234:       /* diagonal portion of A */
5235:       for (j = 0; j < ncols_d; j++) {
5236:         cj[k]   = cstart + *aj++;
5237:         ca[k++] = *aa++;
5238:       }
5239:       /* off-diagonal portion of A */
5240:       for (j = jo; j < ncols_o; j++) {
5241:         cj[k]   = cmap[*bj++];
5242:         ca[k++] = *ba++;
5243:       }
5244:     }
5245:     /* put together the new matrix */
5246:     PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, am, A->cmap->N, ci, cj, ca, A_loc));
5247:     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5248:     /* Since these are PETSc arrays, change flags to free them as necessary. */
5249:     mat          = (Mat_SeqAIJ *)(*A_loc)->data;
5250:     mat->free_a  = PETSC_TRUE;
5251:     mat->free_ij = PETSC_TRUE;
5252:     mat->nonew   = 0;
5253:   } else if (scall == MAT_REUSE_MATRIX) {
5254:     mat = (Mat_SeqAIJ *)(*A_loc)->data;
5255:     ci  = mat->i;
5256:     cj  = mat->j;
5257:     PetscCall(MatSeqAIJGetArrayWrite(*A_loc, &cam));
5258:     for (i = 0; i < am; i++) {
5259:       /* off-diagonal portion of A */
5260:       ncols_o = bi[i + 1] - bi[i];
5261:       for (jo = 0; jo < ncols_o; jo++) {
5262:         col = cmap[*bj];
5263:         if (col >= cstart) break;
5264:         *cam++ = *ba++;
5265:         bj++;
5266:       }
5267:       /* diagonal portion of A */
5268:       ncols_d = ai[i + 1] - ai[i];
5269:       for (j = 0; j < ncols_d; j++) *cam++ = *aa++;
5270:       /* off-diagonal portion of A */
5271:       for (j = jo; j < ncols_o; j++) {
5272:         *cam++ = *ba++;
5273:         bj++;
5274:       }
5275:     }
5276:     PetscCall(MatSeqAIJRestoreArrayWrite(*A_loc, &cam));
5277:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid MatReuse %d", (int)scall);
5278:   PetscCall(MatSeqAIJRestoreArrayRead(mpimat->A, &aav));
5279:   PetscCall(MatSeqAIJRestoreArrayRead(mpimat->B, &bav));
5280:   PetscCall(PetscLogEventEnd(MAT_Getlocalmat, A, 0, 0, 0));
5281:   PetscFunctionReturn(PETSC_SUCCESS);
5282: }

5284: /*@
5285:   MatMPIAIJGetLocalMatMerge - Creates a `MATSEQAIJ` from a `MATMPIAIJ` matrix by taking all its local rows and putting them into a sequential matrix with
5286:   mlocal rows and n columns. Where n is the sum of the number of columns of the diagonal and off-diagonal part

5288:   Not Collective

5290:   Input Parameters:
5291: + A     - the matrix
5292: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5294:   Output Parameters:
5295: + glob  - sequential `IS` with global indices associated with the columns of the local sequential matrix generated (can be `NULL`)
5296: - A_loc - the local sequential matrix generated

5298:   Level: developer

5300:   Note:
5301:   This is different from `MatMPIAIJGetLocalMat()` since the first columns in the returning matrix are those associated with the diagonal
5302:   part, then those associated with the off-diagonal part (in its local ordering)

5304: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMat()`, `MatMPIAIJGetLocalMatCondensed()`
5305: @*/
5306: PetscErrorCode MatMPIAIJGetLocalMatMerge(Mat A, MatReuse scall, IS *glob, Mat *A_loc)
5307: {
5308:   Mat             Ao, Ad;
5309:   const PetscInt *cmap;
5310:   PetscMPIInt     size;
5311:   PetscErrorCode (*f)(Mat, MatReuse, IS *, Mat *);

5313:   PetscFunctionBegin;
5314:   PetscCall(MatMPIAIJGetSeqAIJ(A, &Ad, &Ao, &cmap));
5315:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)A), &size));
5316:   if (size == 1) {
5317:     if (scall == MAT_INITIAL_MATRIX) {
5318:       PetscCall(PetscObjectReference((PetscObject)Ad));
5319:       *A_loc = Ad;
5320:     } else if (scall == MAT_REUSE_MATRIX) {
5321:       PetscCall(MatCopy(Ad, *A_loc, SAME_NONZERO_PATTERN));
5322:     }
5323:     if (glob) PetscCall(ISCreateStride(PetscObjectComm((PetscObject)Ad), Ad->cmap->n, Ad->cmap->rstart, 1, glob));
5324:     PetscFunctionReturn(PETSC_SUCCESS);
5325:   }
5326:   PetscCall(PetscObjectQueryFunction((PetscObject)A, "MatMPIAIJGetLocalMatMerge_C", &f));
5327:   PetscCall(PetscLogEventBegin(MAT_Getlocalmat, A, 0, 0, 0));
5328:   if (f) PetscCall((*f)(A, scall, glob, A_loc));
5329:   else {
5330:     Mat_SeqAIJ        *a = (Mat_SeqAIJ *)Ad->data;
5331:     Mat_SeqAIJ        *b = (Mat_SeqAIJ *)Ao->data;
5332:     Mat_SeqAIJ        *c;
5333:     PetscInt          *ai = a->i, *aj = a->j;
5334:     PetscInt          *bi = b->i, *bj = b->j;
5335:     PetscInt          *ci, *cj;
5336:     const PetscScalar *aa, *ba;
5337:     PetscScalar       *ca;
5338:     PetscInt           i, j, am, dn, on;

5340:     PetscCall(MatGetLocalSize(Ad, &am, &dn));
5341:     PetscCall(MatGetLocalSize(Ao, NULL, &on));
5342:     PetscCall(MatSeqAIJGetArrayRead(Ad, &aa));
5343:     PetscCall(MatSeqAIJGetArrayRead(Ao, &ba));
5344:     if (scall == MAT_INITIAL_MATRIX) {
5345:       PetscInt k;
5346:       PetscCall(PetscMalloc1(1 + am, &ci));
5347:       PetscCall(PetscMalloc1(ai[am] + bi[am], &cj));
5348:       PetscCall(PetscMalloc1(ai[am] + bi[am], &ca));
5349:       ci[0] = 0;
5350:       for (i = 0, k = 0; i < am; i++) {
5351:         const PetscInt ncols_o = bi[i + 1] - bi[i];
5352:         const PetscInt ncols_d = ai[i + 1] - ai[i];
5353:         ci[i + 1]              = ci[i] + ncols_o + ncols_d;
5354:         /* diagonal portion of A */
5355:         for (j = 0; j < ncols_d; j++, k++) {
5356:           cj[k] = *aj++;
5357:           ca[k] = *aa++;
5358:         }
5359:         /* off-diagonal portion of A */
5360:         for (j = 0; j < ncols_o; j++, k++) {
5361:           cj[k] = dn + *bj++;
5362:           ca[k] = *ba++;
5363:         }
5364:       }
5365:       /* put together the new matrix */
5366:       PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, am, dn + on, ci, cj, ca, A_loc));
5367:       /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5368:       /* Since these are PETSc arrays, change flags to free them as necessary. */
5369:       c          = (Mat_SeqAIJ *)(*A_loc)->data;
5370:       c->free_a  = PETSC_TRUE;
5371:       c->free_ij = PETSC_TRUE;
5372:       c->nonew   = 0;
5373:       PetscCall(MatSetType(*A_loc, ((PetscObject)Ad)->type_name));
5374:     } else if (scall == MAT_REUSE_MATRIX) {
5375:       PetscCall(MatSeqAIJGetArrayWrite(*A_loc, &ca));
5376:       for (i = 0; i < am; i++) {
5377:         const PetscInt ncols_d = ai[i + 1] - ai[i];
5378:         const PetscInt ncols_o = bi[i + 1] - bi[i];
5379:         /* diagonal portion of A */
5380:         for (j = 0; j < ncols_d; j++) *ca++ = *aa++;
5381:         /* off-diagonal portion of A */
5382:         for (j = 0; j < ncols_o; j++) *ca++ = *ba++;
5383:       }
5384:       PetscCall(MatSeqAIJRestoreArrayWrite(*A_loc, &ca));
5385:     } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid MatReuse %d", (int)scall);
5386:     PetscCall(MatSeqAIJRestoreArrayRead(Ad, &aa));
5387:     PetscCall(MatSeqAIJRestoreArrayRead(Ao, &aa));
5388:     if (glob) {
5389:       PetscInt cst, *gidx;

5391:       PetscCall(MatGetOwnershipRangeColumn(A, &cst, NULL));
5392:       PetscCall(PetscMalloc1(dn + on, &gidx));
5393:       for (i = 0; i < dn; i++) gidx[i] = cst + i;
5394:       for (i = 0; i < on; i++) gidx[i + dn] = cmap[i];
5395:       PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)Ad), dn + on, gidx, PETSC_OWN_POINTER, glob));
5396:     }
5397:   }
5398:   PetscCall(PetscLogEventEnd(MAT_Getlocalmat, A, 0, 0, 0));
5399:   PetscFunctionReturn(PETSC_SUCCESS);
5400: }

5402: /*@C
5403:   MatMPIAIJGetLocalMatCondensed - Creates a `MATSEQAIJ` matrix from an `MATMPIAIJ` matrix by taking all its local rows and NON-ZERO columns

5405:   Not Collective

5407:   Input Parameters:
5408: + A     - the matrix
5409: . scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`
5410: . row   - index set of rows to extract (or `NULL`)
5411: - col   - index set of columns to extract (or `NULL`)

5413:   Output Parameter:
5414: . A_loc - the local sequential matrix generated

5416:   Level: developer

5418: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMat()`
5419: @*/
5420: PetscErrorCode MatMPIAIJGetLocalMatCondensed(Mat A, MatReuse scall, IS *row, IS *col, Mat *A_loc)
5421: {
5422:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
5423:   PetscInt    i, start, end, ncols, nzA, nzB, *cmap, imark, *idx;
5424:   IS          isrowa, iscola;
5425:   Mat        *aloc;
5426:   PetscBool   match;

5428:   PetscFunctionBegin;
5429:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATMPIAIJ, &match));
5430:   PetscCheck(match, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Requires MATMPIAIJ matrix as input");
5431:   PetscCall(PetscLogEventBegin(MAT_Getlocalmatcondensed, A, 0, 0, 0));
5432:   if (!row) {
5433:     start = A->rmap->rstart;
5434:     end   = A->rmap->rend;
5435:     PetscCall(ISCreateStride(PETSC_COMM_SELF, end - start, start, 1, &isrowa));
5436:   } else {
5437:     isrowa = *row;
5438:   }
5439:   if (!col) {
5440:     start = A->cmap->rstart;
5441:     cmap  = a->garray;
5442:     nzA   = a->A->cmap->n;
5443:     nzB   = a->B->cmap->n;
5444:     PetscCall(PetscMalloc1(nzA + nzB, &idx));
5445:     ncols = 0;
5446:     for (i = 0; i < nzB; i++) {
5447:       if (cmap[i] < start) idx[ncols++] = cmap[i];
5448:       else break;
5449:     }
5450:     imark = i;
5451:     for (i = 0; i < nzA; i++) idx[ncols++] = start + i;
5452:     for (i = imark; i < nzB; i++) idx[ncols++] = cmap[i];
5453:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, &iscola));
5454:   } else {
5455:     iscola = *col;
5456:   }
5457:   if (scall != MAT_INITIAL_MATRIX) {
5458:     PetscCall(PetscMalloc1(1, &aloc));
5459:     aloc[0] = *A_loc;
5460:   }
5461:   PetscCall(MatCreateSubMatrices(A, 1, &isrowa, &iscola, scall, &aloc));
5462:   if (!col) { /* attach global id of condensed columns */
5463:     PetscCall(PetscObjectCompose((PetscObject)aloc[0], "_petsc_GetLocalMatCondensed_iscol", (PetscObject)iscola));
5464:   }
5465:   *A_loc = aloc[0];
5466:   PetscCall(PetscFree(aloc));
5467:   if (!row) PetscCall(ISDestroy(&isrowa));
5468:   if (!col) PetscCall(ISDestroy(&iscola));
5469:   PetscCall(PetscLogEventEnd(MAT_Getlocalmatcondensed, A, 0, 0, 0));
5470:   PetscFunctionReturn(PETSC_SUCCESS);
5471: }

5473: /*
5474:  * Create a sequential AIJ matrix based on row indices. a whole column is extracted once a row is matched.
5475:  * Row could be local or remote.The routine is designed to be scalable in memory so that nothing is based
5476:  * on a global size.
5477:  * */
5478: static PetscErrorCode MatCreateSeqSubMatrixWithRows_Private(Mat P, IS rows, Mat *P_oth)
5479: {
5480:   Mat_MPIAIJ            *p  = (Mat_MPIAIJ *)P->data;
5481:   Mat_SeqAIJ            *pd = (Mat_SeqAIJ *)p->A->data, *po = (Mat_SeqAIJ *)p->B->data, *p_oth;
5482:   PetscInt               plocalsize, nrows, *ilocal, *oilocal, i, lidx, *nrcols, *nlcols, ncol;
5483:   PetscMPIInt            owner;
5484:   PetscSFNode           *iremote, *oiremote;
5485:   const PetscInt        *lrowindices;
5486:   PetscSF                sf, osf;
5487:   PetscInt               pcstart, *roffsets, *loffsets, *pnnz, j;
5488:   PetscInt               ontotalcols, dntotalcols, ntotalcols, nout;
5489:   MPI_Comm               comm;
5490:   ISLocalToGlobalMapping mapping;
5491:   const PetscScalar     *pd_a, *po_a;

5493:   PetscFunctionBegin;
5494:   PetscCall(PetscObjectGetComm((PetscObject)P, &comm));
5495:   /* plocalsize is the number of roots
5496:    * nrows is the number of leaves
5497:    * */
5498:   PetscCall(MatGetLocalSize(P, &plocalsize, NULL));
5499:   PetscCall(ISGetLocalSize(rows, &nrows));
5500:   PetscCall(PetscCalloc1(nrows, &iremote));
5501:   PetscCall(ISGetIndices(rows, &lrowindices));
5502:   for (i = 0; i < nrows; i++) {
5503:     /* Find a remote index and an owner for a row
5504:      * The row could be local or remote
5505:      * */
5506:     owner = 0;
5507:     lidx  = 0;
5508:     PetscCall(PetscLayoutFindOwnerIndex(P->rmap, lrowindices[i], &owner, &lidx));
5509:     iremote[i].index = lidx;
5510:     iremote[i].rank  = owner;
5511:   }
5512:   /* Create SF to communicate how many nonzero columns for each row */
5513:   PetscCall(PetscSFCreate(comm, &sf));
5514:   /* SF will figure out the number of nonzero columns for each row, and their
5515:    * offsets
5516:    * */
5517:   PetscCall(PetscSFSetGraph(sf, plocalsize, nrows, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
5518:   PetscCall(PetscSFSetFromOptions(sf));
5519:   PetscCall(PetscSFSetUp(sf));

5521:   PetscCall(PetscCalloc1(2 * (plocalsize + 1), &roffsets));
5522:   PetscCall(PetscCalloc1(2 * plocalsize, &nrcols));
5523:   PetscCall(PetscCalloc1(nrows, &pnnz));
5524:   roffsets[0] = 0;
5525:   roffsets[1] = 0;
5526:   for (i = 0; i < plocalsize; i++) {
5527:     /* diagonal */
5528:     nrcols[i * 2 + 0] = pd->i[i + 1] - pd->i[i];
5529:     /* off-diagonal */
5530:     nrcols[i * 2 + 1] = po->i[i + 1] - po->i[i];
5531:     /* compute offsets so that we relative location for each row */
5532:     roffsets[(i + 1) * 2 + 0] = roffsets[i * 2 + 0] + nrcols[i * 2 + 0];
5533:     roffsets[(i + 1) * 2 + 1] = roffsets[i * 2 + 1] + nrcols[i * 2 + 1];
5534:   }
5535:   PetscCall(PetscCalloc1(2 * nrows, &nlcols));
5536:   PetscCall(PetscCalloc1(2 * nrows, &loffsets));
5537:   /* 'r' means root, and 'l' means leaf */
5538:   PetscCall(PetscSFBcastBegin(sf, MPIU_2INT, nrcols, nlcols, MPI_REPLACE));
5539:   PetscCall(PetscSFBcastBegin(sf, MPIU_2INT, roffsets, loffsets, MPI_REPLACE));
5540:   PetscCall(PetscSFBcastEnd(sf, MPIU_2INT, nrcols, nlcols, MPI_REPLACE));
5541:   PetscCall(PetscSFBcastEnd(sf, MPIU_2INT, roffsets, loffsets, MPI_REPLACE));
5542:   PetscCall(PetscSFDestroy(&sf));
5543:   PetscCall(PetscFree(roffsets));
5544:   PetscCall(PetscFree(nrcols));
5545:   dntotalcols = 0;
5546:   ontotalcols = 0;
5547:   ncol        = 0;
5548:   for (i = 0; i < nrows; i++) {
5549:     pnnz[i] = nlcols[i * 2 + 0] + nlcols[i * 2 + 1];
5550:     ncol    = PetscMax(pnnz[i], ncol);
5551:     /* diagonal */
5552:     dntotalcols += nlcols[i * 2 + 0];
5553:     /* off-diagonal */
5554:     ontotalcols += nlcols[i * 2 + 1];
5555:   }
5556:   /* We do not need to figure the right number of columns
5557:    * since all the calculations will be done by going through the raw data
5558:    * */
5559:   PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, nrows, ncol, 0, pnnz, P_oth));
5560:   PetscCall(MatSetUp(*P_oth));
5561:   PetscCall(PetscFree(pnnz));
5562:   p_oth = (Mat_SeqAIJ *)(*P_oth)->data;
5563:   /* diagonal */
5564:   PetscCall(PetscCalloc1(dntotalcols, &iremote));
5565:   /* off-diagonal */
5566:   PetscCall(PetscCalloc1(ontotalcols, &oiremote));
5567:   /* diagonal */
5568:   PetscCall(PetscCalloc1(dntotalcols, &ilocal));
5569:   /* off-diagonal */
5570:   PetscCall(PetscCalloc1(ontotalcols, &oilocal));
5571:   dntotalcols = 0;
5572:   ontotalcols = 0;
5573:   ntotalcols  = 0;
5574:   for (i = 0; i < nrows; i++) {
5575:     owner = 0;
5576:     PetscCall(PetscLayoutFindOwnerIndex(P->rmap, lrowindices[i], &owner, NULL));
5577:     /* Set iremote for diag matrix */
5578:     for (j = 0; j < nlcols[i * 2 + 0]; j++) {
5579:       iremote[dntotalcols].index = loffsets[i * 2 + 0] + j;
5580:       iremote[dntotalcols].rank  = owner;
5581:       /* P_oth is seqAIJ so that ilocal need to point to the first part of memory */
5582:       ilocal[dntotalcols++] = ntotalcols++;
5583:     }
5584:     /* off-diagonal */
5585:     for (j = 0; j < nlcols[i * 2 + 1]; j++) {
5586:       oiremote[ontotalcols].index = loffsets[i * 2 + 1] + j;
5587:       oiremote[ontotalcols].rank  = owner;
5588:       oilocal[ontotalcols++]      = ntotalcols++;
5589:     }
5590:   }
5591:   PetscCall(ISRestoreIndices(rows, &lrowindices));
5592:   PetscCall(PetscFree(loffsets));
5593:   PetscCall(PetscFree(nlcols));
5594:   PetscCall(PetscSFCreate(comm, &sf));
5595:   /* P serves as roots and P_oth is leaves
5596:    * Diag matrix
5597:    * */
5598:   PetscCall(PetscSFSetGraph(sf, pd->i[plocalsize], dntotalcols, ilocal, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
5599:   PetscCall(PetscSFSetFromOptions(sf));
5600:   PetscCall(PetscSFSetUp(sf));

5602:   PetscCall(PetscSFCreate(comm, &osf));
5603:   /* off-diagonal */
5604:   PetscCall(PetscSFSetGraph(osf, po->i[plocalsize], ontotalcols, oilocal, PETSC_OWN_POINTER, oiremote, PETSC_OWN_POINTER));
5605:   PetscCall(PetscSFSetFromOptions(osf));
5606:   PetscCall(PetscSFSetUp(osf));
5607:   PetscCall(MatSeqAIJGetArrayRead(p->A, &pd_a));
5608:   PetscCall(MatSeqAIJGetArrayRead(p->B, &po_a));
5609:   /* operate on the matrix internal data to save memory */
5610:   PetscCall(PetscSFBcastBegin(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5611:   PetscCall(PetscSFBcastBegin(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5612:   PetscCall(MatGetOwnershipRangeColumn(P, &pcstart, NULL));
5613:   /* Convert to global indices for diag matrix */
5614:   for (i = 0; i < pd->i[plocalsize]; i++) pd->j[i] += pcstart;
5615:   PetscCall(PetscSFBcastBegin(sf, MPIU_INT, pd->j, p_oth->j, MPI_REPLACE));
5616:   /* We want P_oth store global indices */
5617:   PetscCall(ISLocalToGlobalMappingCreate(comm, 1, p->B->cmap->n, p->garray, PETSC_COPY_VALUES, &mapping));
5618:   /* Use memory scalable approach */
5619:   PetscCall(ISLocalToGlobalMappingSetType(mapping, ISLOCALTOGLOBALMAPPINGHASH));
5620:   PetscCall(ISLocalToGlobalMappingApply(mapping, po->i[plocalsize], po->j, po->j));
5621:   PetscCall(PetscSFBcastBegin(osf, MPIU_INT, po->j, p_oth->j, MPI_REPLACE));
5622:   PetscCall(PetscSFBcastEnd(sf, MPIU_INT, pd->j, p_oth->j, MPI_REPLACE));
5623:   /* Convert back to local indices */
5624:   for (i = 0; i < pd->i[plocalsize]; i++) pd->j[i] -= pcstart;
5625:   PetscCall(PetscSFBcastEnd(osf, MPIU_INT, po->j, p_oth->j, MPI_REPLACE));
5626:   nout = 0;
5627:   PetscCall(ISGlobalToLocalMappingApply(mapping, IS_GTOLM_DROP, po->i[plocalsize], po->j, &nout, po->j));
5628:   PetscCheck(nout == po->i[plocalsize], comm, PETSC_ERR_ARG_INCOMP, "n %" PetscInt_FMT " does not equal to nout %" PetscInt_FMT " ", po->i[plocalsize], nout);
5629:   PetscCall(ISLocalToGlobalMappingDestroy(&mapping));
5630:   /* Exchange values */
5631:   PetscCall(PetscSFBcastEnd(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5632:   PetscCall(PetscSFBcastEnd(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5633:   PetscCall(MatSeqAIJRestoreArrayRead(p->A, &pd_a));
5634:   PetscCall(MatSeqAIJRestoreArrayRead(p->B, &po_a));
5635:   /* Stop PETSc from shrinking memory */
5636:   for (i = 0; i < nrows; i++) p_oth->ilen[i] = p_oth->imax[i];
5637:   PetscCall(MatAssemblyBegin(*P_oth, MAT_FINAL_ASSEMBLY));
5638:   PetscCall(MatAssemblyEnd(*P_oth, MAT_FINAL_ASSEMBLY));
5639:   /* Attach PetscSF objects to P_oth so that we can reuse it later */
5640:   PetscCall(PetscObjectCompose((PetscObject)*P_oth, "diagsf", (PetscObject)sf));
5641:   PetscCall(PetscObjectCompose((PetscObject)*P_oth, "offdiagsf", (PetscObject)osf));
5642:   PetscCall(PetscSFDestroy(&sf));
5643:   PetscCall(PetscSFDestroy(&osf));
5644:   PetscFunctionReturn(PETSC_SUCCESS);
5645: }

5647: /*
5648:  * Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns of local A
5649:  * This supports MPIAIJ and MAIJ
5650:  * */
5651: PetscErrorCode MatGetBrowsOfAcols_MPIXAIJ(Mat A, Mat P, PetscInt dof, MatReuse reuse, Mat *P_oth)
5652: {
5653:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data, *p = (Mat_MPIAIJ *)P->data;
5654:   Mat_SeqAIJ *p_oth;
5655:   IS          rows, map;
5656:   PetscHMapI  hamp;
5657:   PetscInt    i, htsize, *rowindices, off, *mapping, key, count;
5658:   MPI_Comm    comm;
5659:   PetscSF     sf, osf;
5660:   PetscBool   has;

5662:   PetscFunctionBegin;
5663:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
5664:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAocols, A, P, 0, 0));
5665:   /* If it is the first time, create an index set of off-diag nonzero columns of A,
5666:    *  and then create a submatrix (that often is an overlapping matrix)
5667:    * */
5668:   if (reuse == MAT_INITIAL_MATRIX) {
5669:     /* Use a hash table to figure out unique keys */
5670:     PetscCall(PetscHMapICreateWithSize(a->B->cmap->n, &hamp));
5671:     PetscCall(PetscCalloc1(a->B->cmap->n, &mapping));
5672:     count = 0;
5673:     /* Assume that  a->g is sorted, otherwise the following does not make sense */
5674:     for (i = 0; i < a->B->cmap->n; i++) {
5675:       key = a->garray[i] / dof;
5676:       PetscCall(PetscHMapIHas(hamp, key, &has));
5677:       if (!has) {
5678:         mapping[i] = count;
5679:         PetscCall(PetscHMapISet(hamp, key, count++));
5680:       } else {
5681:         /* Current 'i' has the same value the previous step */
5682:         mapping[i] = count - 1;
5683:       }
5684:     }
5685:     PetscCall(ISCreateGeneral(comm, a->B->cmap->n, mapping, PETSC_OWN_POINTER, &map));
5686:     PetscCall(PetscHMapIGetSize(hamp, &htsize));
5687:     PetscCheck(htsize == count, comm, PETSC_ERR_ARG_INCOMP, " Size of hash map %" PetscInt_FMT " is inconsistent with count %" PetscInt_FMT, htsize, count);
5688:     PetscCall(PetscCalloc1(htsize, &rowindices));
5689:     off = 0;
5690:     PetscCall(PetscHMapIGetKeys(hamp, &off, rowindices));
5691:     PetscCall(PetscHMapIDestroy(&hamp));
5692:     PetscCall(PetscSortInt(htsize, rowindices));
5693:     PetscCall(ISCreateGeneral(comm, htsize, rowindices, PETSC_OWN_POINTER, &rows));
5694:     /* In case, the matrix was already created but users want to recreate the matrix */
5695:     PetscCall(MatDestroy(P_oth));
5696:     PetscCall(MatCreateSeqSubMatrixWithRows_Private(P, rows, P_oth));
5697:     PetscCall(PetscObjectCompose((PetscObject)*P_oth, "aoffdiagtopothmapping", (PetscObject)map));
5698:     PetscCall(ISDestroy(&map));
5699:     PetscCall(ISDestroy(&rows));
5700:   } else if (reuse == MAT_REUSE_MATRIX) {
5701:     /* If matrix was already created, we simply update values using SF objects
5702:      * that as attached to the matrix earlier.
5703:      */
5704:     const PetscScalar *pd_a, *po_a;

5706:     PetscCall(PetscObjectQuery((PetscObject)*P_oth, "diagsf", (PetscObject *)&sf));
5707:     PetscCall(PetscObjectQuery((PetscObject)*P_oth, "offdiagsf", (PetscObject *)&osf));
5708:     PetscCheck(sf && osf, comm, PETSC_ERR_ARG_NULL, "Matrix is not initialized yet");
5709:     p_oth = (Mat_SeqAIJ *)(*P_oth)->data;
5710:     /* Update values in place */
5711:     PetscCall(MatSeqAIJGetArrayRead(p->A, &pd_a));
5712:     PetscCall(MatSeqAIJGetArrayRead(p->B, &po_a));
5713:     PetscCall(PetscSFBcastBegin(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5714:     PetscCall(PetscSFBcastBegin(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5715:     PetscCall(PetscSFBcastEnd(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5716:     PetscCall(PetscSFBcastEnd(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5717:     PetscCall(MatSeqAIJRestoreArrayRead(p->A, &pd_a));
5718:     PetscCall(MatSeqAIJRestoreArrayRead(p->B, &po_a));
5719:   } else SETERRQ(comm, PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown reuse type");
5720:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAocols, A, P, 0, 0));
5721:   PetscFunctionReturn(PETSC_SUCCESS);
5722: }

5724: /*@C
5725:   MatGetBrowsOfAcols - Returns `IS` that contain rows of `B` that equal to nonzero columns of local `A`

5727:   Collective

5729:   Input Parameters:
5730: + A     - the first matrix in `MATMPIAIJ` format
5731: . B     - the second matrix in `MATMPIAIJ` format
5732: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5734:   Output Parameters:
5735: + rowb  - On input index sets of rows of B to extract (or `NULL`), modified on output
5736: . colb  - On input index sets of columns of B to extract (or `NULL`), modified on output
5737: - B_seq - the sequential matrix generated

5739:   Level: developer

5741: .seealso: `Mat`, `MATMPIAIJ`, `IS`, `MatReuse`
5742: @*/
5743: PetscErrorCode MatGetBrowsOfAcols(Mat A, Mat B, MatReuse scall, IS *rowb, IS *colb, Mat *B_seq)
5744: {
5745:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
5746:   PetscInt   *idx, i, start, ncols, nzA, nzB, *cmap, imark;
5747:   IS          isrowb, iscolb;
5748:   Mat        *bseq = NULL;

5750:   PetscFunctionBegin;
5751:   PetscCheck(A->cmap->rstart == B->rmap->rstart && A->cmap->rend == B->rmap->rend, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Matrix local dimensions are incompatible, (%" PetscInt_FMT ", %" PetscInt_FMT ") != (%" PetscInt_FMT ",%" PetscInt_FMT ")",
5752:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
5753:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAcols, A, B, 0, 0));

5755:   if (scall == MAT_INITIAL_MATRIX) {
5756:     start = A->cmap->rstart;
5757:     cmap  = a->garray;
5758:     nzA   = a->A->cmap->n;
5759:     nzB   = a->B->cmap->n;
5760:     PetscCall(PetscMalloc1(nzA + nzB, &idx));
5761:     ncols = 0;
5762:     for (i = 0; i < nzB; i++) { /* row < local row index */
5763:       if (cmap[i] < start) idx[ncols++] = cmap[i];
5764:       else break;
5765:     }
5766:     imark = i;
5767:     for (i = 0; i < nzA; i++) idx[ncols++] = start + i;   /* local rows */
5768:     for (i = imark; i < nzB; i++) idx[ncols++] = cmap[i]; /* row > local row index */
5769:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, &isrowb));
5770:     PetscCall(ISCreateStride(PETSC_COMM_SELF, B->cmap->N, 0, 1, &iscolb));
5771:   } else {
5772:     PetscCheck(rowb && colb, PETSC_COMM_SELF, PETSC_ERR_SUP, "IS rowb and colb must be provided for MAT_REUSE_MATRIX");
5773:     isrowb = *rowb;
5774:     iscolb = *colb;
5775:     PetscCall(PetscMalloc1(1, &bseq));
5776:     bseq[0] = *B_seq;
5777:   }
5778:   PetscCall(MatCreateSubMatrices(B, 1, &isrowb, &iscolb, scall, &bseq));
5779:   *B_seq = bseq[0];
5780:   PetscCall(PetscFree(bseq));
5781:   if (!rowb) {
5782:     PetscCall(ISDestroy(&isrowb));
5783:   } else {
5784:     *rowb = isrowb;
5785:   }
5786:   if (!colb) {
5787:     PetscCall(ISDestroy(&iscolb));
5788:   } else {
5789:     *colb = iscolb;
5790:   }
5791:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAcols, A, B, 0, 0));
5792:   PetscFunctionReturn(PETSC_SUCCESS);
5793: }

5795: // PetscClangLinter pragma disable: -fdoc-sowing-chars
5796: /*
5797:   MatGetBrowsOfAoCols_MPIAIJ - Creates a `MATSEQAIJ` matrix by taking rows of B that equal to nonzero columns
5798:   of the OFF-DIAGONAL portion of local A

5800:   Collective

5802:   Input Parameters:
5803: + A     - the first matrix in `MATMPIAIJ` format
5804: . B     - the second matrix in `MATMPIAIJ` format
5805: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5807:   Output Parameters:
5808: + startsj_s - starting point in B's sending j-arrays, saved for MAT_REUSE (or NULL)
5809: . startsj_r - starting point in B's receiving j-arrays, saved for MAT_REUSE (or NULL)
5810: . bufa_ptr  - array for sending matrix values, saved for MAT_REUSE (or NULL)
5811: - B_oth     - the sequential matrix generated with size aBn=a->B->cmap->n by B->cmap->N

5813:   Level: developer

5815:   Developer Note:
5816:   This directly accesses information inside the VecScatter associated with the matrix-vector product
5817:   for this matrix. This is not desirable.

5819: .seealso: [](ch_mat), `Mat`, `MATMPIAIJ`
5820: */
5821: PetscErrorCode MatGetBrowsOfAoCols_MPIAIJ(Mat A, Mat B, MatReuse scall, PetscInt **startsj_s, PetscInt **startsj_r, MatScalar **bufa_ptr, Mat *B_oth)
5822: {
5823:   Mat_MPIAIJ        *a = (Mat_MPIAIJ *)A->data;
5824:   VecScatter         ctx;
5825:   MPI_Comm           comm;
5826:   const PetscMPIInt *rprocs, *sprocs;
5827:   PetscMPIInt        nrecvs, nsends;
5828:   const PetscInt    *srow, *rstarts, *sstarts;
5829:   PetscInt          *rowlen, *bufj, *bufJ, ncols = 0, aBn = a->B->cmap->n, row, *b_othi, *b_othj, *rvalues = NULL, *svalues = NULL, *cols, sbs, rbs;
5830:   PetscInt           i, j, k = 0, l, ll, nrows, *rstartsj = NULL, *sstartsj, len;
5831:   PetscScalar       *b_otha, *bufa, *bufA, *vals = NULL;
5832:   MPI_Request       *reqs = NULL, *rwaits = NULL, *swaits = NULL;
5833:   PetscMPIInt        size, tag, rank, nreqs;

5835:   PetscFunctionBegin;
5836:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
5837:   PetscCallMPI(MPI_Comm_size(comm, &size));

5839:   PetscCheck(A->cmap->rstart == B->rmap->rstart && A->cmap->rend == B->rmap->rend, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Matrix local dimensions are incompatible, (%" PetscInt_FMT ", %" PetscInt_FMT ") != (%" PetscInt_FMT ",%" PetscInt_FMT ")",
5840:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
5841:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAocols, A, B, 0, 0));
5842:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

5844:   if (size == 1) {
5845:     startsj_s = NULL;
5846:     bufa_ptr  = NULL;
5847:     *B_oth    = NULL;
5848:     PetscFunctionReturn(PETSC_SUCCESS);
5849:   }

5851:   ctx = a->Mvctx;
5852:   tag = ((PetscObject)ctx)->tag;

5854:   PetscCall(VecScatterGetRemote_Private(ctx, PETSC_TRUE /*send*/, &nsends, &sstarts, &srow, &sprocs, &sbs));
5855:   /* rprocs[] must be ordered so that indices received from them are ordered in rvalues[], which is key to algorithms used in this subroutine */
5856:   PetscCall(VecScatterGetRemoteOrdered_Private(ctx, PETSC_FALSE /*recv*/, &nrecvs, &rstarts, NULL /*indices not needed*/, &rprocs, &rbs));
5857:   PetscCall(PetscMPIIntCast(nsends + nrecvs, &nreqs));
5858:   PetscCall(PetscMalloc1(nreqs, &reqs));
5859:   rwaits = reqs;
5860:   swaits = PetscSafePointerPlusOffset(reqs, nrecvs);

5862:   if (!startsj_s || !bufa_ptr) scall = MAT_INITIAL_MATRIX;
5863:   if (scall == MAT_INITIAL_MATRIX) {
5864:     /* i-array */
5865:     /*  post receives */
5866:     if (nrecvs) PetscCall(PetscMalloc1(rbs * (rstarts[nrecvs] - rstarts[0]), &rvalues)); /* rstarts can be NULL when nrecvs=0 */
5867:     for (i = 0; i < nrecvs; i++) {
5868:       rowlen = rvalues + rstarts[i] * rbs;
5869:       nrows  = (rstarts[i + 1] - rstarts[i]) * rbs; /* num of indices to be received */
5870:       PetscCallMPI(MPIU_Irecv(rowlen, nrows, MPIU_INT, rprocs[i], tag, comm, rwaits + i));
5871:     }

5873:     /* pack the outgoing message */
5874:     PetscCall(PetscMalloc2(nsends + 1, &sstartsj, nrecvs + 1, &rstartsj));

5876:     sstartsj[0] = 0;
5877:     rstartsj[0] = 0;
5878:     len         = 0; /* total length of j or a array to be sent */
5879:     if (nsends) {
5880:       k = sstarts[0]; /* ATTENTION: sstarts[0] and rstarts[0] are not necessarily zero */
5881:       PetscCall(PetscMalloc1(sbs * (sstarts[nsends] - sstarts[0]), &svalues));
5882:     }
5883:     for (i = 0; i < nsends; i++) {
5884:       rowlen = svalues + (sstarts[i] - sstarts[0]) * sbs;
5885:       nrows  = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5886:       for (j = 0; j < nrows; j++) {
5887:         row = srow[k] + B->rmap->range[rank]; /* global row idx */
5888:         for (l = 0; l < sbs; l++) {
5889:           PetscCall(MatGetRow_MPIAIJ(B, row + l, &ncols, NULL, NULL)); /* rowlength */

5891:           rowlen[j * sbs + l] = ncols;

5893:           len += ncols;
5894:           PetscCall(MatRestoreRow_MPIAIJ(B, row + l, &ncols, NULL, NULL));
5895:         }
5896:         k++;
5897:       }
5898:       PetscCallMPI(MPIU_Isend(rowlen, nrows * sbs, MPIU_INT, sprocs[i], tag, comm, swaits + i));

5900:       sstartsj[i + 1] = len; /* starting point of (i+1)-th outgoing msg in bufj and bufa */
5901:     }
5902:     /* recvs and sends of i-array are completed */
5903:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5904:     PetscCall(PetscFree(svalues));

5906:     /* allocate buffers for sending j and a arrays */
5907:     PetscCall(PetscMalloc1(len, &bufj));
5908:     PetscCall(PetscMalloc1(len, &bufa));

5910:     /* create i-array of B_oth */
5911:     PetscCall(PetscMalloc1(aBn + 1, &b_othi));

5913:     b_othi[0] = 0;
5914:     len       = 0; /* total length of j or a array to be received */
5915:     k         = 0;
5916:     for (i = 0; i < nrecvs; i++) {
5917:       rowlen = rvalues + (rstarts[i] - rstarts[0]) * rbs;
5918:       nrows  = (rstarts[i + 1] - rstarts[i]) * rbs; /* num of rows to be received */
5919:       for (j = 0; j < nrows; j++) {
5920:         b_othi[k + 1] = b_othi[k] + rowlen[j];
5921:         PetscCall(PetscIntSumError(rowlen[j], len, &len));
5922:         k++;
5923:       }
5924:       rstartsj[i + 1] = len; /* starting point of (i+1)-th incoming msg in bufj and bufa */
5925:     }
5926:     PetscCall(PetscFree(rvalues));

5928:     /* allocate space for j and a arrays of B_oth */
5929:     PetscCall(PetscMalloc1(b_othi[aBn], &b_othj));
5930:     PetscCall(PetscMalloc1(b_othi[aBn], &b_otha));

5932:     /* j-array */
5933:     /*  post receives of j-array */
5934:     for (i = 0; i < nrecvs; i++) {
5935:       nrows = rstartsj[i + 1] - rstartsj[i]; /* length of the msg received */
5936:       PetscCallMPI(MPIU_Irecv(PetscSafePointerPlusOffset(b_othj, rstartsj[i]), nrows, MPIU_INT, rprocs[i], tag, comm, rwaits + i));
5937:     }

5939:     /* pack the outgoing message j-array */
5940:     if (nsends) k = sstarts[0];
5941:     for (i = 0; i < nsends; i++) {
5942:       nrows = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5943:       bufJ  = PetscSafePointerPlusOffset(bufj, sstartsj[i]);
5944:       for (j = 0; j < nrows; j++) {
5945:         row = srow[k++] + B->rmap->range[rank]; /* global row idx */
5946:         for (ll = 0; ll < sbs; ll++) {
5947:           PetscCall(MatGetRow_MPIAIJ(B, row + ll, &ncols, &cols, NULL));
5948:           for (l = 0; l < ncols; l++) *bufJ++ = cols[l];
5949:           PetscCall(MatRestoreRow_MPIAIJ(B, row + ll, &ncols, &cols, NULL));
5950:         }
5951:       }
5952:       PetscCallMPI(MPIU_Isend(PetscSafePointerPlusOffset(bufj, sstartsj[i]), sstartsj[i + 1] - sstartsj[i], MPIU_INT, sprocs[i], tag, comm, swaits + i));
5953:     }

5955:     /* recvs and sends of j-array are completed */
5956:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5957:   } else if (scall == MAT_REUSE_MATRIX) {
5958:     sstartsj = *startsj_s;
5959:     rstartsj = *startsj_r;
5960:     bufa     = *bufa_ptr;
5961:     PetscCall(MatSeqAIJGetArrayWrite(*B_oth, &b_otha));
5962:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Matrix P does not possess an object container");

5964:   /* a-array */
5965:   /*  post receives of a-array */
5966:   for (i = 0; i < nrecvs; i++) {
5967:     nrows = rstartsj[i + 1] - rstartsj[i]; /* length of the msg received */
5968:     PetscCallMPI(MPIU_Irecv(PetscSafePointerPlusOffset(b_otha, rstartsj[i]), nrows, MPIU_SCALAR, rprocs[i], tag, comm, rwaits + i));
5969:   }

5971:   /* pack the outgoing message a-array */
5972:   if (nsends) k = sstarts[0];
5973:   for (i = 0; i < nsends; i++) {
5974:     nrows = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5975:     bufA  = PetscSafePointerPlusOffset(bufa, sstartsj[i]);
5976:     for (j = 0; j < nrows; j++) {
5977:       row = srow[k++] + B->rmap->range[rank]; /* global row idx */
5978:       for (ll = 0; ll < sbs; ll++) {
5979:         PetscCall(MatGetRow_MPIAIJ(B, row + ll, &ncols, NULL, &vals));
5980:         for (l = 0; l < ncols; l++) *bufA++ = vals[l];
5981:         PetscCall(MatRestoreRow_MPIAIJ(B, row + ll, &ncols, NULL, &vals));
5982:       }
5983:     }
5984:     PetscCallMPI(MPIU_Isend(PetscSafePointerPlusOffset(bufa, sstartsj[i]), sstartsj[i + 1] - sstartsj[i], MPIU_SCALAR, sprocs[i], tag, comm, swaits + i));
5985:   }
5986:   /* recvs and sends of a-array are completed */
5987:   if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5988:   PetscCall(PetscFree(reqs));

5990:   if (scall == MAT_INITIAL_MATRIX) {
5991:     Mat_SeqAIJ *b_oth;

5993:     /* put together the new matrix */
5994:     PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, aBn, B->cmap->N, b_othi, b_othj, b_otha, B_oth));

5996:     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5997:     /* Since these are PETSc arrays, change flags to free them as necessary. */
5998:     b_oth          = (Mat_SeqAIJ *)(*B_oth)->data;
5999:     b_oth->free_a  = PETSC_TRUE;
6000:     b_oth->free_ij = PETSC_TRUE;
6001:     b_oth->nonew   = 0;

6003:     PetscCall(PetscFree(bufj));
6004:     if (!startsj_s || !bufa_ptr) {
6005:       PetscCall(PetscFree2(sstartsj, rstartsj));
6006:       PetscCall(PetscFree(bufa_ptr));
6007:     } else {
6008:       *startsj_s = sstartsj;
6009:       *startsj_r = rstartsj;
6010:       *bufa_ptr  = bufa;
6011:     }
6012:   } else if (scall == MAT_REUSE_MATRIX) {
6013:     PetscCall(MatSeqAIJRestoreArrayWrite(*B_oth, &b_otha));
6014:   }

6016:   PetscCall(VecScatterRestoreRemote_Private(ctx, PETSC_TRUE, &nsends, &sstarts, &srow, &sprocs, &sbs));
6017:   PetscCall(VecScatterRestoreRemoteOrdered_Private(ctx, PETSC_FALSE, &nrecvs, &rstarts, NULL, &rprocs, &rbs));
6018:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAocols, A, B, 0, 0));
6019:   PetscFunctionReturn(PETSC_SUCCESS);
6020: }

6022: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCRL(Mat, MatType, MatReuse, Mat *);
6023: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJPERM(Mat, MatType, MatReuse, Mat *);
6024: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJSELL(Mat, MatType, MatReuse, Mat *);
6025: #if PetscDefined(HAVE_MKL_SPARSE)
6026: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJMKL(Mat, MatType, MatReuse, Mat *);
6027: #endif
6028: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIBAIJ(Mat, MatType, MatReuse, Mat *);
6029: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPISBAIJ(Mat, MatType, MatReuse, Mat *);
6030: #if PetscDefined(HAVE_ELEMENTAL)
6031: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_Elemental(Mat, MatType, MatReuse, Mat *);
6032: #endif
6033: #if PetscDefined(HAVE_SCALAPACK) && (PetscDefined(USE_REAL_SINGLE) || PetscDefined(USE_REAL_DOUBLE))
6034: PETSC_INTERN PetscErrorCode MatConvert_AIJ_ScaLAPACK(Mat, MatType, MatReuse, Mat *);
6035: #endif
6036: #if PetscDefined(HAVE_HYPRE)
6037: PETSC_INTERN PetscErrorCode MatConvert_AIJ_HYPRE(Mat, MatType, MatReuse, Mat *);
6038: #endif
6039: #if PetscDefined(HAVE_CUDA)
6040: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCUSPARSE(Mat, MatType, MatReuse, Mat *);
6041: #endif
6042: #if PetscDefined(HAVE_HIP)
6043: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJHIPSPARSE(Mat, MatType, MatReuse, Mat *);
6044: #endif
6045: #if PetscDefined(HAVE_KOKKOS_KERNELS)
6046: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJKokkos(Mat, MatType, MatReuse, Mat *);
6047: #endif
6048: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPISELL(Mat, MatType, MatReuse, Mat *);
6049: PETSC_INTERN PetscErrorCode MatConvert_XAIJ_IS(Mat, MatType, MatReuse, Mat *);
6050: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_IS_XAIJ(Mat);

6052: /*
6053:     Computes (B'*A')' since computing B*A directly is untenable

6055:                n                       p                          p
6056:         [             ]       [             ]         [                 ]
6057:       m [      A      ]  *  n [       B     ]   =   m [         C       ]
6058:         [             ]       [             ]         [                 ]

6060: */
6061: static PetscErrorCode MatMatMultNumeric_MPIDense_MPIAIJ(Mat A, Mat B, Mat C)
6062: {
6063:   Mat At, Bt, Ct;

6065:   PetscFunctionBegin;
6066:   PetscCall(MatTranspose(A, MAT_INITIAL_MATRIX, &At));
6067:   PetscCall(MatTranspose(B, MAT_INITIAL_MATRIX, &Bt));
6068:   PetscCall(MatMatMult(Bt, At, MAT_INITIAL_MATRIX, PETSC_CURRENT, &Ct));
6069:   PetscCall(MatDestroy(&At));
6070:   PetscCall(MatDestroy(&Bt));
6071:   PetscCall(MatTransposeSetPrecursor(Ct, C));
6072:   PetscCall(MatTranspose(Ct, MAT_REUSE_MATRIX, &C));
6073:   PetscCall(MatDestroy(&Ct));
6074:   PetscFunctionReturn(PETSC_SUCCESS);
6075: }

6077: static PetscErrorCode MatMatMultSymbolic_MPIDense_MPIAIJ(Mat A, Mat B, PetscReal fill, Mat C)
6078: {
6079:   PetscBool cisdense;

6081:   PetscFunctionBegin;
6082:   PetscCheck(A->cmap->n == B->rmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "A->cmap->n %" PetscInt_FMT " != B->rmap->n %" PetscInt_FMT, A->cmap->n, B->rmap->n);
6083:   PetscCall(MatSetSizes(C, A->rmap->n, B->cmap->n, A->rmap->N, B->cmap->N));
6084:   PetscCall(MatSetBlockSizesFromMats(C, A, B));
6085:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &cisdense, MATMPIDENSE, MATMPIDENSECUDA, MATMPIDENSEHIP, ""));
6086:   if (!cisdense) PetscCall(MatSetType(C, ((PetscObject)A)->type_name));
6087:   PetscCall(MatSetUp(C));

6089:   C->ops->matmultnumeric = MatMatMultNumeric_MPIDense_MPIAIJ;
6090:   PetscFunctionReturn(PETSC_SUCCESS);
6091: }

6093: static PetscErrorCode MatProductSetFromOptions_MPIDense_MPIAIJ_AB(Mat C)
6094: {
6095:   Mat_Product *product = C->product;
6096:   Mat          A = product->A, B = product->B;

6098:   PetscFunctionBegin;
6099:   PetscCheck(A->cmap->rstart == B->rmap->rstart && A->cmap->rend == B->rmap->rend, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Matrix local dimensions are incompatible, (%" PetscInt_FMT ", %" PetscInt_FMT ") != (%" PetscInt_FMT ",%" PetscInt_FMT ")",
6100:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
6101:   C->ops->matmultsymbolic = MatMatMultSymbolic_MPIDense_MPIAIJ;
6102:   C->ops->productsymbolic = MatProductSymbolic_AB;
6103:   PetscFunctionReturn(PETSC_SUCCESS);
6104: }

6106: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_MPIDense_MPIAIJ(Mat C)
6107: {
6108:   Mat_Product *product = C->product;

6110:   PetscFunctionBegin;
6111:   if (product->type == MATPRODUCT_AB) PetscCall(MatProductSetFromOptions_MPIDense_MPIAIJ_AB(C));
6112:   PetscFunctionReturn(PETSC_SUCCESS);
6113: }

6115: /*
6116:    Merge two sets of sorted nonzeros and return a CSR for the merged (sequential) matrix

6118:   Input Parameters:

6120:     j1,rowBegin1,rowEnd1,jmap1: describe the first set of nonzeros (Set1)
6121:     j2,rowBegin2,rowEnd2,jmap2: describe the second set of nonzeros (Set2)

6123:     mat: both sets' nonzeros are on m rows, where m is the number of local rows of the matrix mat

6125:     For Set1, j1[] contains column indices of the nonzeros.
6126:     For the k-th row (0<=k<m), [rowBegin1[k],rowEnd1[k]) index into j1[] and point to the begin/end nonzero in row k
6127:     respectively (note rowEnd1[k] is not necessarily equal to rwoBegin1[k+1]). Indices in this range of j1[] are sorted,
6128:     but might have repeats. jmap1[t+1] - jmap1[t] is the number of repeats for the t-th unique nonzero in Set1.

6130:     Similar for Set2.

6132:     This routine merges the two sets of nonzeros row by row and removes repeats.

6134:   Output Parameters: (memory is allocated by the caller)

6136:     i[],j[]: the CSR of the merged matrix, which has m rows.
6137:     imap1[]: the k-th unique nonzero in Set1 (k=0,1,...) corresponds to imap1[k]-th unique nonzero in the merged matrix.
6138:     imap2[]: similar to imap1[], but for Set2.
6139:     Note we order nonzeros row-by-row and from left to right.
6140: */
6141: static PetscErrorCode MatMergeEntries_Internal(Mat mat, const PetscInt j1[], const PetscInt j2[], const PetscCount rowBegin1[], const PetscCount rowEnd1[], const PetscCount rowBegin2[], const PetscCount rowEnd2[], const PetscCount jmap1[], const PetscCount jmap2[], PetscCount imap1[], PetscCount imap2[], PetscInt i[], PetscInt j[])
6142: {
6143:   PetscInt   r, m; /* Row index of mat */
6144:   PetscCount t, t1, t2, b1, e1, b2, e2;

6146:   PetscFunctionBegin;
6147:   PetscCall(MatGetLocalSize(mat, &m, NULL));
6148:   t1 = t2 = t = 0; /* Count unique nonzeros of in Set1, Set1 and the merged respectively */
6149:   i[0]        = 0;
6150:   for (r = 0; r < m; r++) { /* Do row by row merging */
6151:     b1 = rowBegin1[r];
6152:     e1 = rowEnd1[r];
6153:     b2 = rowBegin2[r];
6154:     e2 = rowEnd2[r];
6155:     while (b1 < e1 && b2 < e2) {
6156:       if (j1[b1] == j2[b2]) { /* Same column index and hence same nonzero */
6157:         j[t]      = j1[b1];
6158:         imap1[t1] = t;
6159:         imap2[t2] = t;
6160:         b1 += jmap1[t1 + 1] - jmap1[t1]; /* Jump to next unique local nonzero */
6161:         b2 += jmap2[t2 + 1] - jmap2[t2]; /* Jump to next unique remote nonzero */
6162:         t1++;
6163:         t2++;
6164:         t++;
6165:       } else if (j1[b1] < j2[b2]) {
6166:         j[t]      = j1[b1];
6167:         imap1[t1] = t;
6168:         b1 += jmap1[t1 + 1] - jmap1[t1];
6169:         t1++;
6170:         t++;
6171:       } else {
6172:         j[t]      = j2[b2];
6173:         imap2[t2] = t;
6174:         b2 += jmap2[t2 + 1] - jmap2[t2];
6175:         t2++;
6176:         t++;
6177:       }
6178:     }
6179:     /* Merge the remaining in either j1[] or j2[] */
6180:     while (b1 < e1) {
6181:       j[t]      = j1[b1];
6182:       imap1[t1] = t;
6183:       b1 += jmap1[t1 + 1] - jmap1[t1];
6184:       t1++;
6185:       t++;
6186:     }
6187:     while (b2 < e2) {
6188:       j[t]      = j2[b2];
6189:       imap2[t2] = t;
6190:       b2 += jmap2[t2 + 1] - jmap2[t2];
6191:       t2++;
6192:       t++;
6193:     }
6194:     PetscCall(PetscIntCast(t, i + r + 1));
6195:   }
6196:   PetscFunctionReturn(PETSC_SUCCESS);
6197: }

6199: /*
6200:   Split nonzeros in a block of local rows into two subsets: those in the diagonal block and those in the off-diagonal block

6202:   Input Parameters:
6203:     mat: an MPI matrix that provides row and column layout information for splitting. Let's say its number of local rows is m.
6204:     n,i[],j[],perm[]: there are n input entries, belonging to m rows. Row/col indices of the entries are stored in i[] and j[]
6205:       respectively, along with a permutation array perm[]. Length of the i[],j[],perm[] arrays is n.

6207:       i[] is already sorted, but within a row, j[] is not sorted and might have repeats.
6208:       i[] might contain negative indices at the beginning, which means the corresponding entries should be ignored in the splitting.

6210:   Output Parameters:
6211:     j[],perm[]: the routine needs to sort j[] within each row along with perm[].
6212:     rowBegin[],rowMid[],rowEnd[]: of length m, and the memory is preallocated and zeroed by the caller.
6213:       They contain indices pointing to j[]. For 0<=r<m, [rowBegin[r],rowMid[r]) point to begin/end entries of row r of the diagonal block,
6214:       and [rowMid[r],rowEnd[r]) point to begin/end entries of row r of the off-diagonal block.

6216:     Aperm[],Ajmap[],Atot,Annz: Arrays are allocated by this routine.
6217:       Atot: number of entries belonging to the diagonal block.
6218:       Annz: number of unique nonzeros belonging to the diagonal block.
6219:       Aperm[Atot] stores values from perm[] for entries belonging to the diagonal block. Length of Aperm[] is Atot, though it may also count
6220:         repeats (i.e., same 'i,j' pair).
6221:       Ajmap[Annz+1] stores the number of repeats of each unique entry belonging to the diagonal block. More precisely, Ajmap[t+1] - Ajmap[t]
6222:         is the number of repeats for the t-th unique entry in the diagonal block. Ajmap[0] is always 0.

6224:       Atot: number of entries belonging to the diagonal block
6225:       Annz: number of unique nonzeros belonging to the diagonal block.

6227:     Bperm[], Bjmap[], Btot, Bnnz are similar but for the off-diagonal block.

6229:     Aperm[],Bperm[],Ajmap[] and Bjmap[] are allocated separately by this routine with PetscMalloc1().
6230: */
6231: static PetscErrorCode MatSplitEntries_Internal(Mat mat, PetscCount n, const PetscInt i[], PetscInt j[], PetscCount perm[], PetscCount rowBegin[], PetscCount rowMid[], PetscCount rowEnd[], PetscCount *Atot_, PetscCount **Aperm_, PetscCount *Annz_, PetscCount **Ajmap_, PetscCount *Btot_, PetscCount **Bperm_, PetscCount *Bnnz_, PetscCount **Bjmap_)
6232: {
6233:   PetscInt    cstart, cend, rstart, rend, row, col;
6234:   PetscCount  Atot = 0, Btot = 0; /* Total number of nonzeros in the diagonal and off-diagonal blocks */
6235:   PetscCount  Annz = 0, Bnnz = 0; /* Number of unique nonzeros in the diagonal and off-diagonal blocks */
6236:   PetscCount  k, m, p, q, r, s, mid;
6237:   PetscCount *Aperm, *Bperm, *Ajmap, *Bjmap;

6239:   PetscFunctionBegin;
6240:   PetscCall(PetscLayoutGetRange(mat->rmap, &rstart, &rend));
6241:   PetscCall(PetscLayoutGetRange(mat->cmap, &cstart, &cend));
6242:   m = rend - rstart;

6244:   /* Skip negative rows */
6245:   for (k = 0; k < n; k++)
6246:     if (i[k] >= 0) break;

6248:   /* Process [k,n): sort and partition each local row into diag and offdiag portions,
6249:      fill rowBegin[], rowMid[], rowEnd[], and count Atot, Btot, Annz, Bnnz.
6250:   */
6251:   while (k < n) {
6252:     row = i[k];
6253:     /* Entries in [k,s) are in one row. Shift diagonal block col indices so that diag is ahead of offdiag after sorting the row */
6254:     for (s = k; s < n; s++)
6255:       if (i[s] != row) break;

6257:     /* Shift diag columns to range of [-PETSC_INT_MAX, -1] */
6258:     for (p = k; p < s; p++) {
6259:       if (j[p] >= cstart && j[p] < cend) j[p] -= PETSC_INT_MAX;
6260:     }
6261:     PetscCall(PetscSortIntWithCountArray(s - k, j + k, perm + k));
6262:     PetscCall(PetscSortedIntUpperBound(j, k, s, -1, &mid)); /* Separate [k,s) into [k,mid) for diag and [mid,s) for offdiag */
6263:     rowBegin[row - rstart] = k;
6264:     rowMid[row - rstart]   = mid;
6265:     rowEnd[row - rstart]   = s;
6266:     PetscCheck(k == s || j[s - 1] < mat->cmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column index %" PetscInt_FMT " is >= matrix column size %" PetscInt_FMT, j[s - 1], mat->cmap->N);

6268:     /* Count nonzeros of this diag/offdiag row, which might have repeats */
6269:     Atot += mid - k;
6270:     Btot += s - mid;

6272:     /* Count unique nonzeros of this diag row */
6273:     for (p = k; p < mid;) {
6274:       col = j[p];
6275:       do {
6276:         j[p] += PETSC_INT_MAX; /* Revert the modified diagonal indices */
6277:         p++;
6278:       } while (p < mid && j[p] == col);
6279:       Annz++;
6280:     }

6282:     /* Count unique nonzeros of this offdiag row */
6283:     for (p = mid; p < s;) {
6284:       col = j[p];
6285:       do {
6286:         p++;
6287:       } while (p < s && j[p] == col);
6288:       Bnnz++;
6289:     }
6290:     k = s;
6291:   }

6293:   /* Allocation according to Atot, Btot, Annz, Bnnz */
6294:   PetscCall(PetscMalloc1(Atot, &Aperm));
6295:   PetscCall(PetscMalloc1(Btot, &Bperm));
6296:   PetscCall(PetscMalloc1(Annz + 1, &Ajmap));
6297:   PetscCall(PetscMalloc1(Bnnz + 1, &Bjmap));

6299:   /* Re-scan indices and copy diag/offdiag permutation indices to Aperm, Bperm and also fill Ajmap and Bjmap */
6300:   Ajmap[0] = Bjmap[0] = Atot = Btot = Annz = Bnnz = 0;
6301:   for (r = 0; r < m; r++) {
6302:     k   = rowBegin[r];
6303:     mid = rowMid[r];
6304:     s   = rowEnd[r];
6305:     PetscCall(PetscArraycpy(PetscSafePointerPlusOffset(Aperm, Atot), PetscSafePointerPlusOffset(perm, k), mid - k));
6306:     PetscCall(PetscArraycpy(PetscSafePointerPlusOffset(Bperm, Btot), PetscSafePointerPlusOffset(perm, mid), s - mid));
6307:     Atot += mid - k;
6308:     Btot += s - mid;

6310:     /* Scan column indices in this row and find out how many repeats each unique nonzero has */
6311:     for (p = k; p < mid;) {
6312:       col = j[p];
6313:       q   = p;
6314:       do {
6315:         p++;
6316:       } while (p < mid && j[p] == col);
6317:       Ajmap[Annz + 1] = Ajmap[Annz] + (p - q);
6318:       Annz++;
6319:     }

6321:     for (p = mid; p < s;) {
6322:       col = j[p];
6323:       q   = p;
6324:       do {
6325:         p++;
6326:       } while (p < s && j[p] == col);
6327:       Bjmap[Bnnz + 1] = Bjmap[Bnnz] + (p - q);
6328:       Bnnz++;
6329:     }
6330:   }
6331:   /* Output */
6332:   *Aperm_ = Aperm;
6333:   *Annz_  = Annz;
6334:   *Atot_  = Atot;
6335:   *Ajmap_ = Ajmap;
6336:   *Bperm_ = Bperm;
6337:   *Bnnz_  = Bnnz;
6338:   *Btot_  = Btot;
6339:   *Bjmap_ = Bjmap;
6340:   PetscFunctionReturn(PETSC_SUCCESS);
6341: }

6343: /*
6344:   Expand the jmap[] array to make a new one in view of nonzeros in the merged matrix

6346:   Input Parameters:
6347:     nnz1: number of unique nonzeros in a set that was used to produce imap[], jmap[]
6348:     nnz:  number of unique nonzeros in the merged matrix
6349:     imap[nnz1]: i-th nonzero in the set is the imap[i]-th nonzero in the merged matrix
6350:     jmap[nnz1+1]: i-th nonzero in the set has jmap[i+1] - jmap[i] repeats in the set

6352:   Output Parameter: (memory is allocated by the caller)
6353:     jmap_new[nnz+1]: i-th nonzero in the merged matrix has jmap_new[i+1] - jmap_new[i] repeats in the set

6355:   Example:
6356:     nnz1 = 4
6357:     nnz  = 6
6358:     imap = [1,3,4,5]
6359:     jmap = [0,3,5,6,7]
6360:    then,
6361:     jmap_new = [0,0,3,3,5,6,7]
6362: */
6363: static PetscErrorCode ExpandJmap_Internal(PetscCount nnz1, PetscCount nnz, const PetscCount imap[], const PetscCount jmap[], PetscCount jmap_new[])
6364: {
6365:   PetscCount k, p;

6367:   PetscFunctionBegin;
6368:   jmap_new[0] = 0;
6369:   p           = nnz;                /* p loops over jmap_new[] backwards */
6370:   for (k = nnz1 - 1; k >= 0; k--) { /* k loops over imap[] */
6371:     for (; p > imap[k]; p--) jmap_new[p] = jmap[k + 1];
6372:   }
6373:   for (; p >= 0; p--) jmap_new[p] = jmap[0];
6374:   PetscFunctionReturn(PETSC_SUCCESS);
6375: }

6377: static PetscErrorCode MatCOOStructDestroy_MPIAIJ(PetscCtxRt data)
6378: {
6379:   MatCOOStruct_MPIAIJ *coo = *(MatCOOStruct_MPIAIJ **)data;

6381:   PetscFunctionBegin;
6382:   PetscCall(PetscSFDestroy(&coo->sf));
6383:   PetscCall(PetscFree(coo->Aperm1));
6384:   PetscCall(PetscFree(coo->Bperm1));
6385:   PetscCall(PetscFree(coo->Ajmap1));
6386:   PetscCall(PetscFree(coo->Bjmap1));
6387:   PetscCall(PetscFree(coo->Aimap2));
6388:   PetscCall(PetscFree(coo->Bimap2));
6389:   PetscCall(PetscFree(coo->Aperm2));
6390:   PetscCall(PetscFree(coo->Bperm2));
6391:   PetscCall(PetscFree(coo->Ajmap2));
6392:   PetscCall(PetscFree(coo->Bjmap2));
6393:   PetscCall(PetscFree(coo->Cperm1));
6394:   PetscCall(PetscFree2(coo->sendbuf, coo->recvbuf));
6395:   PetscCall(PetscFree(coo));
6396:   PetscFunctionReturn(PETSC_SUCCESS);
6397: }

6399: PetscErrorCode MatSetPreallocationCOO_MPIAIJ(Mat mat, PetscCount coo_n, PetscInt coo_i[], PetscInt coo_j[])
6400: {
6401:   MPI_Comm             comm;
6402:   PetscMPIInt          rank, size;
6403:   PetscInt             m, n, M, N, rstart, rend, cstart, cend; /* Sizes, indices of row/col, therefore with type PetscInt */
6404:   PetscCount           k, p, q, rem;                           /* Loop variables over coo arrays */
6405:   Mat_MPIAIJ          *mpiaij = (Mat_MPIAIJ *)mat->data;
6406:   PetscContainer       container;
6407:   MatCOOStruct_MPIAIJ *coo;

6409:   PetscFunctionBegin;
6410:   PetscCall(PetscFree(mpiaij->garray));
6411:   PetscCall(VecDestroy(&mpiaij->lvec));
6412: #if PetscDefined(USE_CTABLE)
6413:   PetscCall(PetscHMapIDestroy(&mpiaij->colmap));
6414: #else
6415:   PetscCall(PetscFree(mpiaij->colmap));
6416: #endif
6417:   PetscCall(VecScatterDestroy(&mpiaij->Mvctx));
6418:   mat->assembled     = PETSC_FALSE;
6419:   mat->was_assembled = PETSC_FALSE;

6421:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
6422:   PetscCallMPI(MPI_Comm_size(comm, &size));
6423:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
6424:   PetscCall(PetscLayoutSetUp(mat->rmap));
6425:   PetscCall(PetscLayoutSetUp(mat->cmap));
6426:   PetscCall(PetscLayoutGetRange(mat->rmap, &rstart, &rend));
6427:   PetscCall(PetscLayoutGetRange(mat->cmap, &cstart, &cend));
6428:   PetscCall(MatGetLocalSize(mat, &m, &n));
6429:   PetscCall(MatGetSize(mat, &M, &N));

6431:   /* Sort (i,j) by row along with a permutation array, so that the to-be-ignored */
6432:   /* entries come first, then local rows, then remote rows.                     */
6433:   PetscCount n1 = coo_n, *perm1;
6434:   PetscInt  *i1 = coo_i, *j1 = coo_j;

6436:   PetscCall(PetscMalloc1(n1, &perm1));
6437:   for (k = 0; k < n1; k++) perm1[k] = k;

6439:   /* Manipulate indices so that entries with negative row or col indices will have smallest
6440:      row indices, local entries will have greater but negative row indices, and remote entries
6441:      will have positive row indices.
6442:   */
6443:   for (k = 0; k < n1; k++) {
6444:     if (i1[k] < 0 || j1[k] < 0) i1[k] = PETSC_INT_MIN;                /* e.g., -2^31, minimal to move them ahead */
6445:     else if (i1[k] >= rstart && i1[k] < rend) i1[k] -= PETSC_INT_MAX; /* e.g., minus 2^31-1 to shift local rows to range of [-PETSC_INT_MAX, -1] */
6446:     else {
6447:       PetscCheck(!mat->nooffprocentries, PETSC_COMM_SELF, PETSC_ERR_USER_INPUT, "MAT_NO_OFF_PROC_ENTRIES is set but insert to remote rows");
6448:       if (mpiaij->donotstash) i1[k] = PETSC_INT_MIN; /* Ignore offproc entries as if they had negative indices */
6449:     }
6450:   }

6452:   /* Sort by row; after that, [0,k) have ignored entries, [k,rem) have local rows and [rem,n1) have remote rows */
6453:   PetscCall(PetscSortIntWithIntCountArrayPair(n1, i1, j1, perm1));

6455:   /* Advance k to the first entry we need to take care of */
6456:   for (k = 0; k < n1; k++)
6457:     if (i1[k] > PETSC_INT_MIN) break;
6458:   PetscCount i1start = k;

6460:   PetscCall(PetscSortedIntUpperBound(i1, k, n1, rend - 1 - PETSC_INT_MAX, &rem)); /* rem is upper bound of the last local row */
6461:   for (; k < rem; k++) i1[k] += PETSC_INT_MAX;                                    /* Revert row indices of local rows*/

6463:   PetscCheck(n1 == 0 || i1[n1 - 1] < M, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "COO row index %" PetscInt_FMT " is >= the matrix row size %" PetscInt_FMT, i1[n1 - 1], M);

6465:   /*           Send remote rows to their owner                                  */
6466:   /* Find which rows should be sent to which remote ranks*/
6467:   PetscInt        nsend = 0; /* Number of MPI ranks to send data to */
6468:   PetscMPIInt    *sendto;    /* [nsend], storing remote ranks */
6469:   PetscInt       *nentries;  /* [nsend], storing number of entries sent to remote ranks; Assume PetscInt is big enough for this count, and error if not */
6470:   const PetscInt *ranges;
6471:   PetscInt        maxNsend = size >= 128 ? 128 : size; /* Assume max 128 neighbors; realloc when needed */

6473:   PetscCall(PetscLayoutGetRanges(mat->rmap, &ranges));
6474:   PetscCall(PetscMalloc2(maxNsend, &sendto, maxNsend, &nentries));
6475:   for (k = rem; k < n1;) {
6476:     PetscMPIInt owner;
6477:     PetscInt    firstRow, lastRow;

6479:     /* Locate a row range */
6480:     firstRow = i1[k]; /* first row of this owner */
6481:     PetscCall(PetscLayoutFindOwner(mat->rmap, firstRow, &owner));
6482:     lastRow = ranges[owner + 1] - 1; /* last row of this owner */

6484:     /* Find the first index 'p' in [k,n) with i1[p] belonging to next owner */
6485:     PetscCall(PetscSortedIntUpperBound(i1, k, n1, lastRow, &p));

6487:     /* All entries in [k,p) belong to this remote owner */
6488:     if (nsend >= maxNsend) { /* Double the remote ranks arrays if not long enough */
6489:       PetscMPIInt *sendto2;
6490:       PetscInt    *nentries2;
6491:       PetscInt     maxNsend2 = (maxNsend <= size / 2) ? maxNsend * 2 : size;

6493:       PetscCall(PetscMalloc2(maxNsend2, &sendto2, maxNsend2, &nentries2));
6494:       PetscCall(PetscArraycpy(sendto2, sendto, maxNsend));
6495:       PetscCall(PetscArraycpy(nentries2, nentries, maxNsend));
6496:       PetscCall(PetscFree2(sendto, nentries));
6497:       sendto   = sendto2;
6498:       nentries = nentries2;
6499:       maxNsend = maxNsend2;
6500:     }
6501:     sendto[nsend] = owner;
6502:     PetscCall(PetscIntCast(p - k, &nentries[nsend]));
6503:     nsend++;
6504:     k = p;
6505:   }

6507:   /* Build 1st SF to know offsets on remote to send data */
6508:   PetscSF      sf1;
6509:   PetscInt     nroots = 1, nroots2 = 0;
6510:   PetscInt     nleaves = nsend, nleaves2 = 0;
6511:   PetscInt    *offsets;
6512:   PetscSFNode *iremote;

6514:   PetscCall(PetscSFCreate(comm, &sf1));
6515:   PetscCall(PetscMalloc1(nsend, &iremote));
6516:   PetscCall(PetscMalloc1(nsend, &offsets));
6517:   for (k = 0; k < nsend; k++) {
6518:     iremote[k].rank  = sendto[k];
6519:     iremote[k].index = 0;
6520:     nleaves2 += nentries[k];
6521:     PetscCheck(nleaves2 >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of SF leaves is too large for PetscInt");
6522:   }
6523:   PetscCall(PetscSFSetGraph(sf1, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
6524:   PetscCall(PetscSFFetchAndOpWithMemTypeBegin(sf1, MPIU_INT, PETSC_MEMTYPE_HOST, &nroots2 /*rootdata*/, PETSC_MEMTYPE_HOST, nentries /*leafdata*/, PETSC_MEMTYPE_HOST, offsets /*leafupdate*/, MPI_SUM));
6525:   PetscCall(PetscSFFetchAndOpEnd(sf1, MPIU_INT, &nroots2, nentries, offsets, MPI_SUM)); /* Would nroots2 overflow, we check offsets[] below */
6526:   PetscCall(PetscSFDestroy(&sf1));
6527:   PetscAssert(nleaves2 == n1 - rem, PETSC_COMM_SELF, PETSC_ERR_PLIB, "nleaves2 %" PetscInt_FMT " != number of remote entries %" PetscCount_FMT, nleaves2, n1 - rem);

6529:   /* Build 2nd SF to send remote COOs to their owner */
6530:   PetscSF sf2;
6531:   nroots  = nroots2;
6532:   nleaves = nleaves2;
6533:   PetscCall(PetscSFCreate(comm, &sf2));
6534:   PetscCall(PetscSFSetFromOptions(sf2));
6535:   PetscCall(PetscMalloc1(nleaves, &iremote));
6536:   p = 0;
6537:   for (k = 0; k < nsend; k++) {
6538:     PetscCheck(offsets[k] >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of SF roots is too large for PetscInt");
6539:     for (q = 0; q < nentries[k]; q++, p++) {
6540:       iremote[p].rank = sendto[k];
6541:       PetscCall(PetscIntCast(offsets[k] + q, &iremote[p].index));
6542:     }
6543:   }
6544:   PetscCall(PetscSFSetGraph(sf2, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));

6546:   /* Send the remote COOs to their owner */
6547:   PetscInt    n2 = nroots, *i2, *j2; /* Buffers for received COOs from other ranks, along with a permutation array */
6548:   PetscCount *perm2;                 /* Though PetscInt is enough for remote entries, we use PetscCount here as we want to reuse MatSplitEntries_Internal() */
6549:   PetscCall(PetscMalloc3(n2, &i2, n2, &j2, n2, &perm2));
6550:   PetscAssert(rem == 0 || i1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6551:   PetscAssert(rem == 0 || j1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6552:   PetscInt *i1prem = PetscSafePointerPlusOffset(i1, rem);
6553:   PetscInt *j1prem = PetscSafePointerPlusOffset(j1, rem);
6554:   PetscCall(PetscSFReduceWithMemTypeBegin(sf2, MPIU_INT, PETSC_MEMTYPE_HOST, i1prem, PETSC_MEMTYPE_HOST, i2, MPI_REPLACE));
6555:   PetscCall(PetscSFReduceEnd(sf2, MPIU_INT, i1prem, i2, MPI_REPLACE));
6556:   PetscCall(PetscSFReduceWithMemTypeBegin(sf2, MPIU_INT, PETSC_MEMTYPE_HOST, j1prem, PETSC_MEMTYPE_HOST, j2, MPI_REPLACE));
6557:   PetscCall(PetscSFReduceEnd(sf2, MPIU_INT, j1prem, j2, MPI_REPLACE));

6559:   PetscCall(PetscFree(offsets));
6560:   PetscCall(PetscFree2(sendto, nentries));

6562:   /* Sort received COOs by row along with the permutation array     */
6563:   for (k = 0; k < n2; k++) perm2[k] = k;
6564:   PetscCall(PetscSortIntWithIntCountArrayPair(n2, i2, j2, perm2));

6566:   /* sf2 only sends contiguous leafdata to contiguous rootdata. We record the permutation which will be used to fill leafdata */
6567:   PetscCount *Cperm1;
6568:   PetscAssert(rem == 0 || perm1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6569:   PetscCount *perm1prem = PetscSafePointerPlusOffset(perm1, rem);
6570:   PetscCall(PetscMalloc1(nleaves, &Cperm1));
6571:   PetscCall(PetscArraycpy(Cperm1, perm1prem, nleaves));

6573:   /* Support for HYPRE matrices, kind of a hack.
6574:      Swap min column with diagonal so that diagonal values will go first */
6575:   PetscBool hypre;
6576:   PetscCall(PetscStrcmp("_internal_COO_mat_for_hypre", ((PetscObject)mat)->name, &hypre));
6577:   if (hypre) {
6578:     PetscInt *minj;
6579:     PetscBT   hasdiag;

6581:     PetscCall(PetscBTCreate(m, &hasdiag));
6582:     PetscCall(PetscMalloc1(m, &minj));
6583:     for (k = 0; k < m; k++) minj[k] = PETSC_INT_MAX;
6584:     for (k = i1start; k < rem; k++) {
6585:       if (j1[k] < cstart || j1[k] >= cend) continue;
6586:       const PetscInt rindex = i1[k] - rstart;
6587:       if ((j1[k] - cstart) == rindex) PetscCall(PetscBTSet(hasdiag, rindex));
6588:       minj[rindex] = PetscMin(minj[rindex], j1[k]);
6589:     }
6590:     for (k = 0; k < n2; k++) {
6591:       if (j2[k] < cstart || j2[k] >= cend) continue;
6592:       const PetscInt rindex = i2[k] - rstart;
6593:       if ((j2[k] - cstart) == rindex) PetscCall(PetscBTSet(hasdiag, rindex));
6594:       minj[rindex] = PetscMin(minj[rindex], j2[k]);
6595:     }
6596:     for (k = i1start; k < rem; k++) {
6597:       const PetscInt rindex = i1[k] - rstart;
6598:       if (j1[k] < cstart || j1[k] >= cend || !PetscBTLookup(hasdiag, rindex)) continue;
6599:       if (j1[k] == minj[rindex]) j1[k] = i1[k] + (cstart - rstart);
6600:       else if ((j1[k] - cstart) == rindex) j1[k] = minj[rindex];
6601:     }
6602:     for (k = 0; k < n2; k++) {
6603:       const PetscInt rindex = i2[k] - rstart;
6604:       if (j2[k] < cstart || j2[k] >= cend || !PetscBTLookup(hasdiag, rindex)) continue;
6605:       if (j2[k] == minj[rindex]) j2[k] = i2[k] + (cstart - rstart);
6606:       else if ((j2[k] - cstart) == rindex) j2[k] = minj[rindex];
6607:     }
6608:     PetscCall(PetscBTDestroy(&hasdiag));
6609:     PetscCall(PetscFree(minj));
6610:   }

6612:   /* Split local COOs and received COOs into diag/offdiag portions */
6613:   PetscCount *rowBegin1, *rowMid1, *rowEnd1;
6614:   PetscCount *Ajmap1, *Aperm1, *Bjmap1, *Bperm1;
6615:   PetscCount  Annz1, Bnnz1, Atot1, Btot1;
6616:   PetscCount *rowBegin2, *rowMid2, *rowEnd2;
6617:   PetscCount *Ajmap2, *Aperm2, *Bjmap2, *Bperm2;
6618:   PetscCount  Annz2, Bnnz2, Atot2, Btot2;

6620:   PetscCall(PetscCalloc3(m, &rowBegin1, m, &rowMid1, m, &rowEnd1));
6621:   PetscCall(PetscCalloc3(m, &rowBegin2, m, &rowMid2, m, &rowEnd2));
6622:   PetscCall(MatSplitEntries_Internal(mat, rem, i1, j1, perm1, rowBegin1, rowMid1, rowEnd1, &Atot1, &Aperm1, &Annz1, &Ajmap1, &Btot1, &Bperm1, &Bnnz1, &Bjmap1));
6623:   PetscCall(MatSplitEntries_Internal(mat, n2, i2, j2, perm2, rowBegin2, rowMid2, rowEnd2, &Atot2, &Aperm2, &Annz2, &Ajmap2, &Btot2, &Bperm2, &Bnnz2, &Bjmap2));

6625:   /* Merge local COOs with received COOs: diag with diag, offdiag with offdiag */
6626:   PetscInt *Ai, *Bi;
6627:   PetscInt *Aj, *Bj;

6629:   PetscCall(PetscMalloc1(m + 1, &Ai));
6630:   PetscCall(PetscMalloc1(m + 1, &Bi));
6631:   PetscCall(PetscMalloc1(Annz1 + Annz2, &Aj)); /* Since local and remote entries might have dups, we might allocate excess memory */
6632:   PetscCall(PetscMalloc1(Bnnz1 + Bnnz2, &Bj));

6634:   PetscCount *Aimap1, *Bimap1, *Aimap2, *Bimap2;
6635:   PetscCall(PetscMalloc1(Annz1, &Aimap1));
6636:   PetscCall(PetscMalloc1(Bnnz1, &Bimap1));
6637:   PetscCall(PetscMalloc1(Annz2, &Aimap2));
6638:   PetscCall(PetscMalloc1(Bnnz2, &Bimap2));

6640:   PetscCall(MatMergeEntries_Internal(mat, j1, j2, rowBegin1, rowMid1, rowBegin2, rowMid2, Ajmap1, Ajmap2, Aimap1, Aimap2, Ai, Aj));
6641:   PetscCall(MatMergeEntries_Internal(mat, j1, j2, rowMid1, rowEnd1, rowMid2, rowEnd2, Bjmap1, Bjmap2, Bimap1, Bimap2, Bi, Bj));

6643:   /* Expand Ajmap1/Bjmap1 to make them based off nonzeros in A/B, since we     */
6644:   /* expect nonzeros in A/B most likely have local contributing entries        */
6645:   PetscInt    Annz = Ai[m];
6646:   PetscInt    Bnnz = Bi[m];
6647:   PetscCount *Ajmap1_new, *Bjmap1_new;

6649:   PetscCall(PetscMalloc1(Annz + 1, &Ajmap1_new));
6650:   PetscCall(PetscMalloc1(Bnnz + 1, &Bjmap1_new));

6652:   PetscCall(ExpandJmap_Internal(Annz1, Annz, Aimap1, Ajmap1, Ajmap1_new));
6653:   PetscCall(ExpandJmap_Internal(Bnnz1, Bnnz, Bimap1, Bjmap1, Bjmap1_new));

6655:   PetscCall(PetscFree(Aimap1));
6656:   PetscCall(PetscFree(Ajmap1));
6657:   PetscCall(PetscFree(Bimap1));
6658:   PetscCall(PetscFree(Bjmap1));
6659:   PetscCall(PetscFree3(rowBegin1, rowMid1, rowEnd1));
6660:   PetscCall(PetscFree3(rowBegin2, rowMid2, rowEnd2));
6661:   PetscCall(PetscFree(perm1));
6662:   PetscCall(PetscFree3(i2, j2, perm2));

6664:   Ajmap1 = Ajmap1_new;
6665:   Bjmap1 = Bjmap1_new;

6667:   /* Reallocate Aj, Bj once we know actual numbers of unique nonzeros in A and B */
6668:   if (Annz < Annz1 + Annz2) {
6669:     PetscInt *Aj_new;
6670:     PetscCall(PetscMalloc1(Annz, &Aj_new));
6671:     PetscCall(PetscArraycpy(Aj_new, Aj, Annz));
6672:     PetscCall(PetscFree(Aj));
6673:     Aj = Aj_new;
6674:   }

6676:   if (Bnnz < Bnnz1 + Bnnz2) {
6677:     PetscInt *Bj_new;
6678:     PetscCall(PetscMalloc1(Bnnz, &Bj_new));
6679:     PetscCall(PetscArraycpy(Bj_new, Bj, Bnnz));
6680:     PetscCall(PetscFree(Bj));
6681:     Bj = Bj_new;
6682:   }

6684:   /* Create new submatrices for on-process and off-process coupling                  */
6685:   PetscScalar *Aa, *Ba;
6686:   MatType      rtype;
6687:   Mat_SeqAIJ  *a, *b;
6688:   PetscCall(PetscCalloc1(Annz, &Aa)); /* Zero matrix on device */
6689:   PetscCall(PetscCalloc1(Bnnz, &Ba));
6690:   /* make Aj[] local, i.e, based off the start column of the diagonal portion */
6691:   if (cstart) {
6692:     for (k = 0; k < Annz; k++) Aj[k] -= cstart;
6693:   }

6695:   PetscCall(MatGetRootType_Private(mat, &rtype));

6697:   MatSeqXAIJGetOptions_Private(mpiaij->A);
6698:   PetscCall(MatDestroy(&mpiaij->A));
6699:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, n, Ai, Aj, Aa, &mpiaij->A));
6700:   PetscCall(MatSetBlockSizesFromMats(mpiaij->A, mat, mat));
6701:   MatSeqXAIJRestoreOptions_Private(mpiaij->A);

6703:   MatSeqXAIJGetOptions_Private(mpiaij->B);
6704:   PetscCall(MatDestroy(&mpiaij->B));
6705:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, mat->cmap->N, Bi, Bj, Ba, &mpiaij->B));
6706:   PetscCall(MatSetBlockSizesFromMats(mpiaij->B, mat, mat));
6707:   MatSeqXAIJRestoreOptions_Private(mpiaij->B);

6709:   PetscCall(MatSetUpMultiply_MPIAIJ(mat));
6710:   mat->was_assembled = PETSC_TRUE; // was_assembled in effect means the Mvctx is built; doing so avoids redundant MatSetUpMultiply_MPIAIJ
6711:   mat->nonzerostate  = mpiaij->A->nonzerostate + mpiaij->B->nonzerostate;
6712:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &mat->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)mat)));

6714:   a          = (Mat_SeqAIJ *)mpiaij->A->data;
6715:   b          = (Mat_SeqAIJ *)mpiaij->B->data;
6716:   a->free_a  = PETSC_TRUE;
6717:   a->free_ij = PETSC_TRUE;
6718:   b->free_a  = PETSC_TRUE;
6719:   b->free_ij = PETSC_TRUE;
6720:   a->maxnz   = a->nz;
6721:   b->maxnz   = b->nz;

6723:   /* conversion must happen AFTER multiply setup */
6724:   PetscCall(MatConvert(mpiaij->A, rtype, MAT_INPLACE_MATRIX, &mpiaij->A));
6725:   PetscCall(MatConvert(mpiaij->B, rtype, MAT_INPLACE_MATRIX, &mpiaij->B));
6726:   PetscCall(VecDestroy(&mpiaij->lvec));
6727:   PetscCall(MatCreateVecs(mpiaij->B, &mpiaij->lvec, NULL));

6729:   // Put the COO struct in a container and then attach that to the matrix
6730:   PetscCall(PetscMalloc1(1, &coo));
6731:   coo->n       = coo_n;
6732:   coo->sf      = sf2;
6733:   coo->sendlen = nleaves;
6734:   coo->recvlen = nroots;
6735:   coo->Annz    = Annz;
6736:   coo->Bnnz    = Bnnz;
6737:   coo->Annz2   = Annz2;
6738:   coo->Bnnz2   = Bnnz2;
6739:   coo->Atot1   = Atot1;
6740:   coo->Atot2   = Atot2;
6741:   coo->Btot1   = Btot1;
6742:   coo->Btot2   = Btot2;
6743:   coo->Ajmap1  = Ajmap1;
6744:   coo->Aperm1  = Aperm1;
6745:   coo->Bjmap1  = Bjmap1;
6746:   coo->Bperm1  = Bperm1;
6747:   coo->Aimap2  = Aimap2;
6748:   coo->Ajmap2  = Ajmap2;
6749:   coo->Aperm2  = Aperm2;
6750:   coo->Bimap2  = Bimap2;
6751:   coo->Bjmap2  = Bjmap2;
6752:   coo->Bperm2  = Bperm2;
6753:   coo->Cperm1  = Cperm1;
6754:   // Allocate in preallocation. If not used, it has zero cost on host
6755:   PetscCall(PetscMalloc2(coo->sendlen, &coo->sendbuf, coo->recvlen, &coo->recvbuf));
6756:   PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &container));
6757:   PetscCall(PetscContainerSetPointer(container, coo));
6758:   PetscCall(PetscContainerSetCtxDestroy(container, MatCOOStructDestroy_MPIAIJ));
6759:   PetscCall(PetscObjectCompose((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject)container));
6760:   PetscCall(PetscContainerDestroy(&container));
6761:   PetscFunctionReturn(PETSC_SUCCESS);
6762: }

6764: static PetscErrorCode MatSetValuesCOO_MPIAIJ(Mat mat, const PetscScalar v[], InsertMode imode)
6765: {
6766:   Mat_MPIAIJ          *mpiaij = (Mat_MPIAIJ *)mat->data;
6767:   Mat                  A = mpiaij->A, B = mpiaij->B;
6768:   PetscScalar         *Aa, *Ba;
6769:   PetscScalar         *sendbuf, *recvbuf;
6770:   const PetscCount    *Ajmap1, *Ajmap2, *Aimap2;
6771:   const PetscCount    *Bjmap1, *Bjmap2, *Bimap2;
6772:   const PetscCount    *Aperm1, *Aperm2, *Bperm1, *Bperm2;
6773:   const PetscCount    *Cperm1;
6774:   PetscContainer       container;
6775:   MatCOOStruct_MPIAIJ *coo;

6777:   PetscFunctionBegin;
6778:   PetscCall(PetscObjectQuery((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject *)&container));
6779:   PetscCheck(container, PetscObjectComm((PetscObject)mat), PETSC_ERR_PLIB, "Not found MatCOOStruct on this matrix");
6780:   PetscCall(PetscContainerGetPointer(container, &coo));
6781:   sendbuf = coo->sendbuf;
6782:   recvbuf = coo->recvbuf;
6783:   Ajmap1  = coo->Ajmap1;
6784:   Ajmap2  = coo->Ajmap2;
6785:   Aimap2  = coo->Aimap2;
6786:   Bjmap1  = coo->Bjmap1;
6787:   Bjmap2  = coo->Bjmap2;
6788:   Bimap2  = coo->Bimap2;
6789:   Aperm1  = coo->Aperm1;
6790:   Aperm2  = coo->Aperm2;
6791:   Bperm1  = coo->Bperm1;
6792:   Bperm2  = coo->Bperm2;
6793:   Cperm1  = coo->Cperm1;

6795:   PetscCall(MatSeqAIJGetArray(A, &Aa)); /* Might read and write matrix values */
6796:   PetscCall(MatSeqAIJGetArray(B, &Ba));

6798:   /* Pack entries to be sent to remote */
6799:   for (PetscCount i = 0; i < coo->sendlen; i++) sendbuf[i] = v[Cperm1[i]];

6801:   /* Send remote entries to their owner and overlap the communication with local computation */
6802:   PetscCall(PetscSFReduceWithMemTypeBegin(coo->sf, MPIU_SCALAR, PETSC_MEMTYPE_HOST, sendbuf, PETSC_MEMTYPE_HOST, recvbuf, MPI_REPLACE));
6803:   /* Add local entries to A and B */
6804:   for (PetscCount i = 0; i < coo->Annz; i++) { /* All nonzeros in A are either zero'ed or added with a value (i.e., initialized) */
6805:     PetscScalar sum = 0.0;                     /* Do partial summation first to improve numerical stability */
6806:     for (PetscCount k = Ajmap1[i]; k < Ajmap1[i + 1]; k++) sum += v[Aperm1[k]];
6807:     Aa[i] = (imode == INSERT_VALUES ? 0.0 : Aa[i]) + sum;
6808:   }
6809:   for (PetscCount i = 0; i < coo->Bnnz; i++) {
6810:     PetscScalar sum = 0.0;
6811:     for (PetscCount k = Bjmap1[i]; k < Bjmap1[i + 1]; k++) sum += v[Bperm1[k]];
6812:     Ba[i] = (imode == INSERT_VALUES ? 0.0 : Ba[i]) + sum;
6813:   }
6814:   PetscCall(PetscSFReduceEnd(coo->sf, MPIU_SCALAR, sendbuf, recvbuf, MPI_REPLACE));

6816:   /* Add received remote entries to A and B */
6817:   for (PetscCount i = 0; i < coo->Annz2; i++) {
6818:     for (PetscCount k = Ajmap2[i]; k < Ajmap2[i + 1]; k++) Aa[Aimap2[i]] += recvbuf[Aperm2[k]];
6819:   }
6820:   for (PetscCount i = 0; i < coo->Bnnz2; i++) {
6821:     for (PetscCount k = Bjmap2[i]; k < Bjmap2[i + 1]; k++) Ba[Bimap2[i]] += recvbuf[Bperm2[k]];
6822:   }
6823:   PetscCall(MatSeqAIJRestoreArray(A, &Aa));
6824:   PetscCall(MatSeqAIJRestoreArray(B, &Ba));
6825:   PetscFunctionReturn(PETSC_SUCCESS);
6826: }

6828: /*MC
6829:    MATMPIAIJ - MATMPIAIJ = "mpiaij" - A matrix type to be used for parallel sparse matrices.

6831:    Options Database Keys:
6832: . -mat_type mpiaij - sets the matrix type to `MATMPIAIJ` during a call to `MatSetFromOptions()`

6834:    Level: beginner

6836:    Notes:
6837:    `MatSetValues()` may be called for this matrix type with a `NULL` argument for the numerical values,
6838:     in this case the values associated with the rows and columns one passes in are set to zero
6839:     in the matrix

6841:     `MatSetOptions`(,`MAT_STRUCTURE_ONLY`,`PETSC_TRUE`) may be called for this matrix type. In this no
6842:     space is allocated for the nonzero entries and any entries passed with `MatSetValues()` are ignored

6844: .seealso: [](ch_matrices), `Mat`, `MATSEQAIJ`, `MATAIJ`, `MatCreateAIJ()`
6845: M*/
6846: PETSC_EXTERN PetscErrorCode MatCreate_MPIAIJ(Mat B)
6847: {
6848:   Mat_MPIAIJ *b;
6849:   PetscMPIInt size;

6851:   PetscFunctionBegin;
6852:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)B), &size));

6854:   PetscCall(PetscNew(&b));
6855:   B->data       = (void *)b;
6856:   B->ops[0]     = MatOps_Values;
6857:   B->assembled  = PETSC_FALSE;
6858:   B->insertmode = NOT_SET_VALUES;
6859:   b->size       = size;

6861:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)B), &b->rank));

6863:   /* build cache for off array entries formed */
6864:   PetscCall(MatStashCreate_Private(PetscObjectComm((PetscObject)B), 1, &B->stash));

6866:   b->donotstash  = PETSC_FALSE;
6867:   b->colmap      = NULL;
6868:   b->garray      = NULL;
6869:   b->roworiented = PETSC_TRUE;

6871:   /* stuff used for matrix vector multiply */
6872:   b->lvec  = NULL;
6873:   b->Mvctx = NULL;

6875:   /* stuff for MatGetRow() */
6876:   b->rowindices   = NULL;
6877:   b->rowvalues    = NULL;
6878:   b->getrowactive = PETSC_FALSE;

6880:   /* flexible pointer used in CUSPARSE classes */
6881:   b->spptr = NULL;

6883:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetUseScalableIncreaseOverlap_C", MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ));
6884:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatStoreValues_C", MatStoreValues_MPIAIJ));
6885:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatRetrieveValues_C", MatRetrieveValues_MPIAIJ));
6886:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatIsTranspose_C", MatIsTranspose_MPIAIJ));
6887:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetPreallocation_C", MatMPIAIJSetPreallocation_MPIAIJ));
6888:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatResetPreallocation_C", MatResetPreallocation_MPIAIJ));
6889:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatResetHash_C", MatResetHash_MPIAIJ));
6890:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetPreallocationCSR_C", MatMPIAIJSetPreallocationCSR_MPIAIJ));
6891:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatDiagonalScaleLocal_C", MatDiagonalScaleLocal_MPIAIJ));
6892:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijperm_C", MatConvert_MPIAIJ_MPIAIJPERM));
6893:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijsell_C", MatConvert_MPIAIJ_MPIAIJSELL));
6894: #if PetscDefined(HAVE_CUDA)
6895:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijcusparse_C", MatConvert_MPIAIJ_MPIAIJCUSPARSE));
6896: #endif
6897: #if PetscDefined(HAVE_HIP)
6898:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijhipsparse_C", MatConvert_MPIAIJ_MPIAIJHIPSPARSE));
6899: #endif
6900: #if PetscDefined(HAVE_KOKKOS_KERNELS)
6901:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijkokkos_C", MatConvert_MPIAIJ_MPIAIJKokkos));
6902: #endif
6903: #if PetscDefined(HAVE_MKL_SPARSE)
6904:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijmkl_C", MatConvert_MPIAIJ_MPIAIJMKL));
6905: #endif
6906:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijcrl_C", MatConvert_MPIAIJ_MPIAIJCRL));
6907:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpibaij_C", MatConvert_MPIAIJ_MPIBAIJ));
6908:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpisbaij_C", MatConvert_MPIAIJ_MPISBAIJ));
6909:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpidense_C", MatConvert_MPIAIJ_MPIDense));
6910: #if PetscDefined(HAVE_ELEMENTAL)
6911:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_elemental_C", MatConvert_MPIAIJ_Elemental));
6912: #endif
6913: #if PetscDefined(HAVE_SCALAPACK) && (PetscDefined(USE_REAL_SINGLE) || PetscDefined(USE_REAL_DOUBLE))
6914:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_scalapack_C", MatConvert_AIJ_ScaLAPACK));
6915: #endif
6916:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_is_C", MatConvert_XAIJ_IS));
6917:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpisell_C", MatConvert_MPIAIJ_MPISELL));
6918: #if PetscDefined(HAVE_HYPRE)
6919:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_hypre_C", MatConvert_AIJ_HYPRE));
6920:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_transpose_mpiaij_mpiaij_C", MatProductSetFromOptions_Transpose_AIJ_AIJ));
6921: #endif
6922:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_is_mpiaij_C", MatProductSetFromOptions_IS_XAIJ));
6923:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_mpiaij_mpiaij_C", MatProductSetFromOptions_MPIAIJ));
6924:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatSetPreallocationCOO_C", MatSetPreallocationCOO_MPIAIJ));
6925:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatSetValuesCOO_C", MatSetValuesCOO_MPIAIJ));
6926:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatGetMultPetscSF_C", MatGetMultPetscSF_MPIAIJ));
6927:   PetscCall(PetscObjectChangeTypeName((PetscObject)B, MATMPIAIJ));
6928:   PetscFunctionReturn(PETSC_SUCCESS);
6929: }

6931: /*@
6932:   MatCreateMPIAIJWithSplitArrays - creates a `MATMPIAIJ` matrix using arrays that contain the "diagonal"
6933:   and "off-diagonal" part of the matrix in CSR format.

6935:   Collective

6937:   Input Parameters:
6938: + comm - MPI communicator
6939: . m    - number of local rows (Cannot be `PETSC_DECIDE`)
6940: . n    - This value should be the same as the local size used in creating the
6941:          x vector for the matrix-vector product $y = Ax$. (or `PETSC_DECIDE` to have
6942:          calculated if `N` is given) For square matrices `n` is almost always `m`.
6943: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if `m` is given)
6944: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if `n` is given)
6945: . i    - row indices for "diagonal" portion of matrix; that is i[0] = 0, i[row] = i[row-1] + number of elements in that row of the matrix
6946: . j    - column indices, which must be local, i.e., based off the start column of the diagonal portion
6947: . a    - matrix values
6948: . oi   - row indices for "off-diagonal" portion of matrix; that is oi[0] = 0, oi[row] = oi[row-1] + number of elements in that row of the matrix
6949: . oj   - column indices, which must be global, representing global columns in the `MATMPIAIJ` matrix
6950: - oa   - matrix values

6952:   Output Parameter:
6953: . mat - the matrix

6955:   Level: advanced

6957:   Notes:
6958:   The `i`, `j`, and `a` arrays ARE NOT copied by this routine into the internal format used by PETSc (even in Fortran). The user
6959:   must free the arrays once the matrix has been destroyed and not before.

6961:   The `i` and `j` indices are 0 based

6963:   See `MatCreateAIJ()` for the definition of "diagonal" and "off-diagonal" portion of the matrix

6965:   This sets local rows and cannot be used to set off-processor values.

6967:   Use of this routine is discouraged because it is inflexible and cumbersome to use. It is extremely rare that a
6968:   legacy application natively assembles into exactly this split format. The code to do so is nontrivial and does
6969:   not easily support in-place reassembly. It is recommended to use MatSetValues() (or a variant thereof) because
6970:   the resulting assembly is easier to implement, will work with any matrix format, and the user does not have to
6971:   keep track of the underlying array. Use `MatSetOption`(A,`MAT_NO_OFF_PROC_ENTRIES`,`PETSC_TRUE`) to disable all
6972:   communication if it is known that only local entries will be set.

6974: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
6975:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithArrays()`
6976: @*/
6977: PetscErrorCode MatCreateMPIAIJWithSplitArrays(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt M, PetscInt N, PetscInt i[], PetscInt j[], PetscScalar a[], PetscInt oi[], PetscInt oj[], PetscScalar oa[], Mat *mat)
6978: {
6979:   Mat_MPIAIJ *maij;

6981:   PetscFunctionBegin;
6982:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
6983:   PetscCheck(i[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
6984:   PetscCheck(oi[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "oi (row indices) must start with 0");
6985:   PetscCall(MatCreate(comm, mat));
6986:   PetscCall(MatSetSizes(*mat, m, n, M, N));
6987:   PetscCall(MatSetType(*mat, MATMPIAIJ));
6988:   maij = (Mat_MPIAIJ *)(*mat)->data;

6990:   (*mat)->preallocated = PETSC_TRUE;

6992:   PetscCall(PetscLayoutSetUp((*mat)->rmap));
6993:   PetscCall(PetscLayoutSetUp((*mat)->cmap));

6995:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, n, i, j, a, &maij->A));
6996:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, (*mat)->cmap->N, oi, oj, oa, &maij->B));

6998:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
6999:   PetscCall(MatAssemblyBegin(*mat, MAT_FINAL_ASSEMBLY));
7000:   PetscCall(MatAssemblyEnd(*mat, MAT_FINAL_ASSEMBLY));
7001:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_FALSE));
7002:   PetscCall(MatSetOption(*mat, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
7003:   PetscFunctionReturn(PETSC_SUCCESS);
7004: }

7006: typedef struct {
7007:   Mat       *mp;    /* intermediate products */
7008:   PetscBool *mptmp; /* is the intermediate product temporary ? */
7009:   PetscInt   cp;    /* number of intermediate products */

7011:   /* support for MatGetBrowsOfAoCols_MPIAIJ for P_oth */
7012:   PetscInt    *startsj_s, *startsj_r;
7013:   PetscScalar *bufa;
7014:   Mat          P_oth;

7016:   /* may take advantage of merging product->B */
7017:   Mat Bloc; /* B-local by merging diag and off-diag */

7019:   /* cusparse does not have support to split between symbolic and numeric phases.
7020:      When api_user is true, we don't need to update the numerical values
7021:      of the temporary storage */
7022:   PetscBool reusesym;

7024:   /* support for COO values insertion */
7025:   PetscScalar *coo_v, *coo_w; /* store on-process and off-process COO scalars, and used as MPI recv/send buffers respectively */
7026:   PetscInt   **own;           /* own[i] points to address of on-process COO indices for Mat mp[i] */
7027:   PetscInt   **off;           /* off[i] points to address of off-process COO indices for Mat mp[i] */
7028:   PetscBool    hasoffproc;    /* if true, have off-process values insertion (i.e. AtB or PtAP) */
7029:   PetscSF      sf;            /* used for non-local values insertion and memory malloc */
7030:   PetscMemType mtype;

7032:   /* customization */
7033:   PetscBool abmerge;
7034:   PetscBool P_oth_bind;
7035: } MatMatMPIAIJBACKEND;

7037: static PetscErrorCode MatProductCtxDestroy_MatMatMPIAIJBACKEND(PetscCtxRt data)
7038: {
7039:   MatMatMPIAIJBACKEND *mmdata = *(MatMatMPIAIJBACKEND **)data;
7040:   PetscInt             i;

7042:   PetscFunctionBegin;
7043:   PetscCall(PetscFree2(mmdata->startsj_s, mmdata->startsj_r));
7044:   PetscCall(PetscFree(mmdata->bufa));
7045:   PetscCall(PetscSFFree(mmdata->sf, mmdata->mtype, mmdata->coo_v));
7046:   PetscCall(PetscSFFree(mmdata->sf, mmdata->mtype, mmdata->coo_w));
7047:   PetscCall(MatDestroy(&mmdata->P_oth));
7048:   PetscCall(MatDestroy(&mmdata->Bloc));
7049:   PetscCall(PetscSFDestroy(&mmdata->sf));
7050:   for (i = 0; i < mmdata->cp; i++) PetscCall(MatDestroy(&mmdata->mp[i]));
7051:   PetscCall(PetscFree2(mmdata->mp, mmdata->mptmp));
7052:   PetscCall(PetscFree(mmdata->own[0]));
7053:   PetscCall(PetscFree(mmdata->own));
7054:   PetscCall(PetscFree(mmdata->off[0]));
7055:   PetscCall(PetscFree(mmdata->off));
7056:   PetscCall(PetscFree(mmdata));
7057:   PetscFunctionReturn(PETSC_SUCCESS);
7058: }

7060: /* Copy selected n entries with indices in idx[] of A to v[].
7061:    If idx is NULL, copy the whole data array of A to v[]
7062:  */
7063: static PetscErrorCode MatSeqAIJCopySubArray(Mat A, PetscInt n, const PetscInt idx[], PetscScalar v[])
7064: {
7065:   PetscErrorCode (*f)(Mat, PetscInt, const PetscInt[], PetscScalar[]);

7067:   PetscFunctionBegin;
7068:   PetscCall(PetscObjectQueryFunction((PetscObject)A, "MatSeqAIJCopySubArray_C", &f));
7069:   if (f) PetscCall((*f)(A, n, idx, v));
7070:   else {
7071:     const PetscScalar *vv;

7073:     PetscCall(MatSeqAIJGetArrayRead(A, &vv));
7074:     if (n && idx) {
7075:       PetscScalar    *w  = v;
7076:       const PetscInt *oi = idx;

7078:       for (PetscInt j = 0; j < n; j++) *w++ = vv[*oi++];
7079:     } else {
7080:       PetscCall(PetscArraycpy(v, vv, n));
7081:     }
7082:     PetscCall(MatSeqAIJRestoreArrayRead(A, &vv));
7083:   }
7084:   PetscFunctionReturn(PETSC_SUCCESS);
7085: }

7087: static PetscErrorCode MatProductNumeric_MPIAIJBACKEND(Mat C)
7088: {
7089:   MatMatMPIAIJBACKEND *mmdata;
7090:   PetscInt             i, n_d, n_o;

7092:   PetscFunctionBegin;
7093:   MatCheckProduct(C, 1);
7094:   PetscCheck(C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data empty");
7095:   mmdata = (MatMatMPIAIJBACKEND *)C->product->data;
7096:   if (!mmdata->reusesym) { /* update temporary matrices */
7097:     if (mmdata->P_oth) PetscCall(MatGetBrowsOfAoCols_MPIAIJ(C->product->A, C->product->B, MAT_REUSE_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));
7098:     if (mmdata->Bloc) PetscCall(MatMPIAIJGetLocalMatMerge(C->product->B, MAT_REUSE_MATRIX, NULL, &mmdata->Bloc));
7099:   }
7100:   mmdata->reusesym = PETSC_FALSE;

7102:   for (i = 0; i < mmdata->cp; i++) {
7103:     PetscCheck(mmdata->mp[i]->ops->productnumeric, PetscObjectComm((PetscObject)mmdata->mp[i]), PETSC_ERR_PLIB, "Missing numeric op for %s", MatProductTypes[mmdata->mp[i]->product->type]);
7104:     PetscCall((*mmdata->mp[i]->ops->productnumeric)(mmdata->mp[i]));
7105:   }
7106:   for (i = 0, n_d = 0, n_o = 0; i < mmdata->cp; i++) {
7107:     PetscInt noff;

7109:     PetscCall(PetscIntCast(mmdata->off[i + 1] - mmdata->off[i], &noff));
7110:     if (mmdata->mptmp[i]) continue;
7111:     if (noff) {
7112:       PetscInt nown;

7114:       PetscCall(PetscIntCast(mmdata->own[i + 1] - mmdata->own[i], &nown));
7115:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], noff, mmdata->off[i], mmdata->coo_w + n_o));
7116:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], nown, mmdata->own[i], mmdata->coo_v + n_d));
7117:       n_o += noff;
7118:       n_d += nown;
7119:     } else {
7120:       Mat_SeqAIJ *mm = (Mat_SeqAIJ *)mmdata->mp[i]->data;

7122:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], mm->nz, NULL, mmdata->coo_v + n_d));
7123:       n_d += mm->nz;
7124:     }
7125:   }
7126:   if (mmdata->hasoffproc) { /* offprocess insertion */
7127:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_SCALAR, mmdata->coo_w, mmdata->coo_v + n_d));
7128:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_SCALAR, mmdata->coo_w, mmdata->coo_v + n_d));
7129:   }
7130:   PetscCall(MatSetValuesCOO(C, mmdata->coo_v, INSERT_VALUES));
7131:   PetscFunctionReturn(PETSC_SUCCESS);
7132: }

7134: /* Support for Pt * A, A * P, or Pt * A * P */
7135: #define MAX_NUMBER_INTERMEDIATE 4
7136: PetscErrorCode MatProductSymbolic_MPIAIJBACKEND(Mat C)
7137: {
7138:   Mat_Product           *product = C->product;
7139:   Mat                    A, P, mp[MAX_NUMBER_INTERMEDIATE]; /* A, P and a series of intermediate matrices */
7140:   Mat_MPIAIJ            *a, *p;
7141:   MatMatMPIAIJBACKEND   *mmdata;
7142:   ISLocalToGlobalMapping P_oth_l2g = NULL;
7143:   IS                     glob      = NULL;
7144:   const char            *prefix;
7145:   char                   pprefix[256];
7146:   const PetscInt        *globidx, *P_oth_idx;
7147:   PetscInt               i, j, cp, m, n, M, N, *coo_i, *coo_j;
7148:   PetscCount             ncoo, ncoo_d, ncoo_o, ncoo_oown;
7149:   PetscInt               cmapt[MAX_NUMBER_INTERMEDIATE], rmapt[MAX_NUMBER_INTERMEDIATE]; /* col/row map type for each Mat in mp[]. */
7150:                                                                                          /* type-0: consecutive, start from 0; type-1: consecutive with */
7151:                                                                                          /* a base offset; type-2: sparse with a local to global map table */
7152:   const PetscInt *cmapa[MAX_NUMBER_INTERMEDIATE], *rmapa[MAX_NUMBER_INTERMEDIATE];       /* col/row local to global map array (table) for type-2 map type */

7154:   MatProductType ptype;
7155:   PetscBool      mptmp[MAX_NUMBER_INTERMEDIATE], hasoffproc = PETSC_FALSE, iscuda, iship, iskokk;
7156:   PetscMPIInt    size;

7158:   PetscFunctionBegin;
7159:   MatCheckProduct(C, 1);
7160:   PetscCheck(!product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data not empty");
7161:   ptype = product->type;
7162:   if (product->A->symmetric == PETSC_BOOL3_TRUE && ptype == MATPRODUCT_AtB) {
7163:     ptype                                          = MATPRODUCT_AB;
7164:     product->symbolic_used_the_fact_A_is_symmetric = PETSC_TRUE;
7165:   }
7166:   switch (ptype) {
7167:   case MATPRODUCT_AB:
7168:     A          = product->A;
7169:     P          = product->B;
7170:     m          = A->rmap->n;
7171:     n          = P->cmap->n;
7172:     M          = A->rmap->N;
7173:     N          = P->cmap->N;
7174:     hasoffproc = PETSC_FALSE; /* will not scatter mat product values to other processes */
7175:     break;
7176:   case MATPRODUCT_AtB:
7177:     P          = product->A;
7178:     A          = product->B;
7179:     m          = P->cmap->n;
7180:     n          = A->cmap->n;
7181:     M          = P->cmap->N;
7182:     N          = A->cmap->N;
7183:     hasoffproc = PETSC_TRUE;
7184:     break;
7185:   case MATPRODUCT_PtAP:
7186:     A          = product->A;
7187:     P          = product->B;
7188:     m          = P->cmap->n;
7189:     n          = P->cmap->n;
7190:     M          = P->cmap->N;
7191:     N          = P->cmap->N;
7192:     hasoffproc = PETSC_TRUE;
7193:     break;
7194:   default:
7195:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[ptype]);
7196:   }
7197:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)C), &size));
7198:   if (size == 1) hasoffproc = PETSC_FALSE;

7200:   /* defaults */
7201:   for (i = 0; i < MAX_NUMBER_INTERMEDIATE; i++) {
7202:     mp[i]    = NULL;
7203:     mptmp[i] = PETSC_FALSE;
7204:     rmapt[i] = -1;
7205:     cmapt[i] = -1;
7206:     rmapa[i] = NULL;
7207:     cmapa[i] = NULL;
7208:   }

7210:   /* customization */
7211:   PetscCall(PetscNew(&mmdata));
7212:   mmdata->reusesym = product->api_user;
7213:   if (ptype == MATPRODUCT_AB) {
7214:     if (product->api_user) {
7215:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatMatMult", "Mat");
7216:       PetscCall(PetscOptionsBool("-matmatmult_backend_mergeB", "Merge product->B local matrices", "MatMatMult", mmdata->abmerge, &mmdata->abmerge, NULL));
7217:       PetscCall(PetscOptionsBool("-matmatmult_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7218:       PetscOptionsEnd();
7219:     } else {
7220:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_AB", "Mat");
7221:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_mergeB", "Merge product->B local matrices", "MatMatMult", mmdata->abmerge, &mmdata->abmerge, NULL));
7222:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7223:       PetscOptionsEnd();
7224:     }
7225:   } else if (ptype == MATPRODUCT_PtAP) {
7226:     if (product->api_user) {
7227:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatPtAP", "Mat");
7228:       PetscCall(PetscOptionsBool("-matptap_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7229:       PetscOptionsEnd();
7230:     } else {
7231:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_PtAP", "Mat");
7232:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7233:       PetscOptionsEnd();
7234:     }
7235:   }
7236:   a = (Mat_MPIAIJ *)A->data;
7237:   p = (Mat_MPIAIJ *)P->data;
7238:   PetscCall(MatSetSizes(C, m, n, M, N));
7239:   PetscCall(PetscLayoutSetUp(C->rmap));
7240:   PetscCall(PetscLayoutSetUp(C->cmap));
7241:   PetscCall(MatSetType(C, ((PetscObject)A)->type_name));
7242:   PetscCall(MatGetOptionsPrefix(C, &prefix));

7244:   cp = 0;
7245:   switch (ptype) {
7246:   case MATPRODUCT_AB: /* A * P */
7247:     PetscCall(MatGetBrowsOfAoCols_MPIAIJ(A, P, MAT_INITIAL_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));

7249:     /* A_diag * P_local (merged or not) */
7250:     if (mmdata->abmerge) { /* P's diagonal and off-diag blocks are merged to one matrix, then multiplied by A_diag */
7251:       /* P is product->B */
7252:       PetscCall(MatMPIAIJGetLocalMatMerge(P, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7253:       PetscCall(MatProductCreate(a->A, mmdata->Bloc, NULL, &mp[cp]));
7254:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7255:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7256:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7257:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7258:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7259:       mp[cp]->product->api_user = product->api_user;
7260:       PetscCall(MatProductSetFromOptions(mp[cp]));
7261:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7262:       PetscCall(ISGetIndices(glob, &globidx));
7263:       rmapt[cp] = 1;
7264:       cmapt[cp] = 2;
7265:       cmapa[cp] = globidx;
7266:       mptmp[cp] = PETSC_FALSE;
7267:       cp++;
7268:     } else { /* A_diag * P_diag and A_diag * P_off */
7269:       PetscCall(MatProductCreate(a->A, p->A, NULL, &mp[cp]));
7270:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7271:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7272:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7273:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7274:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7275:       mp[cp]->product->api_user = product->api_user;
7276:       PetscCall(MatProductSetFromOptions(mp[cp]));
7277:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7278:       rmapt[cp] = 1;
7279:       cmapt[cp] = 1;
7280:       mptmp[cp] = PETSC_FALSE;
7281:       cp++;
7282:       PetscCall(MatProductCreate(a->A, p->B, NULL, &mp[cp]));
7283:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7284:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7285:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7286:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7287:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7288:       mp[cp]->product->api_user = product->api_user;
7289:       PetscCall(MatProductSetFromOptions(mp[cp]));
7290:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7291:       rmapt[cp] = 1;
7292:       cmapt[cp] = 2;
7293:       cmapa[cp] = p->garray;
7294:       mptmp[cp] = PETSC_FALSE;
7295:       cp++;
7296:     }

7298:     /* A_off * P_other */
7299:     if (mmdata->P_oth) {
7300:       PetscCall(MatSeqAIJCompactOutExtraColumns_SeqAIJ(mmdata->P_oth, &P_oth_l2g)); /* make P_oth use local col ids */
7301:       PetscCall(ISLocalToGlobalMappingGetIndices(P_oth_l2g, &P_oth_idx));
7302:       PetscCall(MatSetType(mmdata->P_oth, ((PetscObject)a->B)->type_name));
7303:       PetscCall(MatBindToCPU(mmdata->P_oth, mmdata->P_oth_bind));
7304:       PetscCall(MatProductCreate(a->B, mmdata->P_oth, NULL, &mp[cp]));
7305:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7306:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7307:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7308:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7309:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7310:       mp[cp]->product->api_user = product->api_user;
7311:       PetscCall(MatProductSetFromOptions(mp[cp]));
7312:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7313:       rmapt[cp] = 1;
7314:       cmapt[cp] = 2;
7315:       cmapa[cp] = P_oth_idx;
7316:       mptmp[cp] = PETSC_FALSE;
7317:       cp++;
7318:     }
7319:     break;

7321:   case MATPRODUCT_AtB: /* (P^t * A): P_diag * A_loc + P_off * A_loc */
7322:     /* A is product->B */
7323:     PetscCall(MatMPIAIJGetLocalMatMerge(A, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7324:     if (A == P) { /* when A==P, we can take advantage of the already merged mmdata->Bloc */
7325:       PetscCall(MatProductCreate(mmdata->Bloc, mmdata->Bloc, NULL, &mp[cp]));
7326:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7327:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7328:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7329:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7330:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7331:       mp[cp]->product->api_user = product->api_user;
7332:       PetscCall(MatProductSetFromOptions(mp[cp]));
7333:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7334:       PetscCall(ISGetIndices(glob, &globidx));
7335:       rmapt[cp] = 2;
7336:       rmapa[cp] = globidx;
7337:       cmapt[cp] = 2;
7338:       cmapa[cp] = globidx;
7339:       mptmp[cp] = PETSC_FALSE;
7340:       cp++;
7341:     } else {
7342:       PetscCall(MatProductCreate(p->A, mmdata->Bloc, NULL, &mp[cp]));
7343:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7344:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7345:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7346:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7347:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7348:       mp[cp]->product->api_user = product->api_user;
7349:       PetscCall(MatProductSetFromOptions(mp[cp]));
7350:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7351:       PetscCall(ISGetIndices(glob, &globidx));
7352:       rmapt[cp] = 1;
7353:       cmapt[cp] = 2;
7354:       cmapa[cp] = globidx;
7355:       mptmp[cp] = PETSC_FALSE;
7356:       cp++;
7357:       PetscCall(MatProductCreate(p->B, mmdata->Bloc, NULL, &mp[cp]));
7358:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7359:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7360:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7361:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7362:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7363:       mp[cp]->product->api_user = product->api_user;
7364:       PetscCall(MatProductSetFromOptions(mp[cp]));
7365:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7366:       rmapt[cp] = 2;
7367:       rmapa[cp] = p->garray;
7368:       cmapt[cp] = 2;
7369:       cmapa[cp] = globidx;
7370:       mptmp[cp] = PETSC_FALSE;
7371:       cp++;
7372:     }
7373:     break;
7374:   case MATPRODUCT_PtAP:
7375:     PetscCall(MatGetBrowsOfAoCols_MPIAIJ(A, P, MAT_INITIAL_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));
7376:     /* P is product->B */
7377:     PetscCall(MatMPIAIJGetLocalMatMerge(P, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7378:     PetscCall(MatProductCreate(a->A, mmdata->Bloc, NULL, &mp[cp]));
7379:     PetscCall(MatProductSetType(mp[cp], MATPRODUCT_PtAP));
7380:     PetscCall(MatProductSetFill(mp[cp], product->fill));
7381:     PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7382:     PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7383:     PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7384:     mp[cp]->product->api_user = product->api_user;
7385:     PetscCall(MatProductSetFromOptions(mp[cp]));
7386:     PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7387:     PetscCall(ISGetIndices(glob, &globidx));
7388:     rmapt[cp] = 2;
7389:     rmapa[cp] = globidx;
7390:     cmapt[cp] = 2;
7391:     cmapa[cp] = globidx;
7392:     mptmp[cp] = PETSC_FALSE;
7393:     cp++;
7394:     if (mmdata->P_oth) {
7395:       PetscCall(MatSeqAIJCompactOutExtraColumns_SeqAIJ(mmdata->P_oth, &P_oth_l2g));
7396:       PetscCall(ISLocalToGlobalMappingGetIndices(P_oth_l2g, &P_oth_idx));
7397:       PetscCall(MatSetType(mmdata->P_oth, ((PetscObject)a->B)->type_name));
7398:       PetscCall(MatBindToCPU(mmdata->P_oth, mmdata->P_oth_bind));
7399:       PetscCall(MatProductCreate(a->B, mmdata->P_oth, NULL, &mp[cp]));
7400:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7401:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7402:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7403:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7404:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7405:       mp[cp]->product->api_user = product->api_user;
7406:       PetscCall(MatProductSetFromOptions(mp[cp]));
7407:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7408:       mptmp[cp] = PETSC_TRUE;
7409:       cp++;
7410:       PetscCall(MatProductCreate(mmdata->Bloc, mp[1], NULL, &mp[cp]));
7411:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7412:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7413:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7414:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7415:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7416:       mp[cp]->product->api_user = product->api_user;
7417:       PetscCall(MatProductSetFromOptions(mp[cp]));
7418:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7419:       rmapt[cp] = 2;
7420:       rmapa[cp] = globidx;
7421:       cmapt[cp] = 2;
7422:       cmapa[cp] = P_oth_idx;
7423:       mptmp[cp] = PETSC_FALSE;
7424:       cp++;
7425:     }
7426:     break;
7427:   default:
7428:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[ptype]);
7429:   }
7430:   /* sanity check */
7431:   if (size > 1)
7432:     for (i = 0; i < cp; i++) PetscCheck(rmapt[i] != 2 || hasoffproc, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Unexpected offproc map type for product %" PetscInt_FMT, i);

7434:   PetscCall(PetscMalloc2(cp, &mmdata->mp, cp, &mmdata->mptmp));
7435:   for (i = 0; i < cp; i++) {
7436:     mmdata->mp[i]    = mp[i];
7437:     mmdata->mptmp[i] = mptmp[i];
7438:   }
7439:   mmdata->cp             = cp;
7440:   C->product->data       = mmdata;
7441:   C->product->destroy    = MatProductCtxDestroy_MatMatMPIAIJBACKEND;
7442:   C->ops->productnumeric = MatProductNumeric_MPIAIJBACKEND;

7444:   /* memory type */
7445:   mmdata->mtype = PETSC_MEMTYPE_HOST;
7446:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iscuda, MATSEQAIJCUSPARSE, MATMPIAIJCUSPARSE, ""));
7447:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iship, MATSEQAIJHIPSPARSE, MATMPIAIJHIPSPARSE, ""));
7448:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iskokk, MATSEQAIJKOKKOS, MATMPIAIJKOKKOS, ""));
7449:   if (iscuda) mmdata->mtype = PETSC_MEMTYPE_CUDA;
7450:   else if (iship) mmdata->mtype = PETSC_MEMTYPE_HIP;
7451:   else if (iskokk) mmdata->mtype = PETSC_MEMTYPE_KOKKOS;

7453:   /* prepare coo coordinates for values insertion */

7455:   /* count total nonzeros of those intermediate seqaij Mats
7456:     ncoo_d:    # of nonzeros of matrices that do not have offproc entries
7457:     ncoo_o:    # of nonzeros (of matrices that might have offproc entries) that will be inserted to remote procs
7458:     ncoo_oown: # of nonzeros (of matrices that might have offproc entries) that will be inserted locally
7459:   */
7460:   for (cp = 0, ncoo_d = 0, ncoo_o = 0, ncoo_oown = 0; cp < mmdata->cp; cp++) {
7461:     Mat_SeqAIJ *mm = (Mat_SeqAIJ *)mp[cp]->data;
7462:     if (mptmp[cp]) continue;
7463:     if (rmapt[cp] == 2 && hasoffproc) { /* the rows need to be scatter to all processes (might include self) */
7464:       const PetscInt *rmap = rmapa[cp];
7465:       const PetscInt  mr   = mp[cp]->rmap->n;
7466:       const PetscInt  rs   = C->rmap->rstart;
7467:       const PetscInt  re   = C->rmap->rend;
7468:       const PetscInt *ii   = mm->i;
7469:       for (i = 0; i < mr; i++) {
7470:         const PetscInt gr = rmap[i];
7471:         const PetscInt nz = ii[i + 1] - ii[i];
7472:         if (gr < rs || gr >= re) ncoo_o += nz; /* this row is offproc */
7473:         else ncoo_oown += nz;                  /* this row is local */
7474:       }
7475:     } else ncoo_d += mm->nz;
7476:   }

7478:   /*
7479:     ncoo: total number of nonzeros (including those inserted by remote procs) belonging to this proc

7481:     ncoo = ncoo_d + ncoo_oown + ncoo2, which ncoo2 is number of nonzeros inserted to me by other procs.

7483:     off[0] points to a big index array, which is shared by off[1,2,...]. Similarly, for own[0].

7485:     off[p]: points to the segment for matrix mp[p], storing location of nonzeros that mp[p] will insert to others
7486:     own[p]: points to the segment for matrix mp[p], storing location of nonzeros that mp[p] will insert locally
7487:     so, off[p+1]-off[p] is the number of nonzeros that mp[p] will send to others.

7489:     coo_i/j/v[]: [ncoo] row/col/val of nonzeros belonging to this proc.
7490:     Ex. coo_i[]: the beginning part (of size ncoo_d + ncoo_oown) stores i of local nonzeros, and the remaining part stores i of nonzeros I will receive.
7491:   */
7492:   PetscCall(PetscCalloc1(mmdata->cp + 1, &mmdata->off)); /* +1 to make a csr-like data structure */
7493:   PetscCall(PetscCalloc1(mmdata->cp + 1, &mmdata->own));

7495:   /* gather (i,j) of nonzeros inserted by remote procs */
7496:   if (hasoffproc) {
7497:     PetscSF  msf;
7498:     PetscInt ncoo2, *coo_i2, *coo_j2;

7500:     PetscCall(PetscMalloc1(ncoo_o, &mmdata->off[0]));
7501:     PetscCall(PetscMalloc1(ncoo_oown, &mmdata->own[0]));
7502:     PetscCall(PetscMalloc2(ncoo_o, &coo_i, ncoo_o, &coo_j)); /* to collect (i,j) of entries to be sent to others */

7504:     for (cp = 0, ncoo_o = 0; cp < mmdata->cp; cp++) {
7505:       Mat_SeqAIJ *mm     = (Mat_SeqAIJ *)mp[cp]->data;
7506:       PetscInt   *idxoff = mmdata->off[cp];
7507:       PetscInt   *idxown = mmdata->own[cp];
7508:       if (!mptmp[cp] && rmapt[cp] == 2) { /* row map is sparse */
7509:         const PetscInt *rmap = rmapa[cp];
7510:         const PetscInt *cmap = cmapa[cp];
7511:         const PetscInt *ii   = mm->i;
7512:         PetscInt       *coi  = coo_i + ncoo_o;
7513:         PetscInt       *coj  = coo_j + ncoo_o;
7514:         const PetscInt  mr   = mp[cp]->rmap->n;
7515:         const PetscInt  rs   = C->rmap->rstart;
7516:         const PetscInt  re   = C->rmap->rend;
7517:         const PetscInt  cs   = C->cmap->rstart;
7518:         for (i = 0; i < mr; i++) {
7519:           const PetscInt *jj = mm->j + ii[i];
7520:           const PetscInt  gr = rmap[i];
7521:           const PetscInt  nz = ii[i + 1] - ii[i];
7522:           if (gr < rs || gr >= re) { /* this is an offproc row */
7523:             for (j = ii[i]; j < ii[i + 1]; j++) {
7524:               *coi++    = gr;
7525:               *idxoff++ = j;
7526:             }
7527:             if (!cmapt[cp]) { /* already global */
7528:               for (j = 0; j < nz; j++) *coj++ = jj[j];
7529:             } else if (cmapt[cp] == 1) { /* local to global for owned columns of C */
7530:               for (j = 0; j < nz; j++) *coj++ = jj[j] + cs;
7531:             } else { /* offdiag */
7532:               for (j = 0; j < nz; j++) *coj++ = cmap[jj[j]];
7533:             }
7534:             ncoo_o += nz;
7535:           } else { /* this is a local row */
7536:             for (j = ii[i]; j < ii[i + 1]; j++) *idxown++ = j;
7537:           }
7538:         }
7539:       }
7540:       mmdata->off[cp + 1] = idxoff;
7541:       mmdata->own[cp + 1] = idxown;
7542:     }

7544:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)C), &mmdata->sf));
7545:     PetscInt incoo_o;
7546:     PetscCall(PetscIntCast(ncoo_o, &incoo_o));
7547:     PetscCall(PetscSFSetGraphLayout(mmdata->sf, C->rmap, incoo_o /*nleaves*/, NULL /*ilocal*/, PETSC_OWN_POINTER, coo_i));
7548:     PetscCall(PetscSFGetMultiSF(mmdata->sf, &msf));
7549:     PetscCall(PetscSFGetGraph(msf, &ncoo2 /*nroots*/, NULL, NULL, NULL));
7550:     ncoo = ncoo_d + ncoo_oown + ncoo2;
7551:     PetscCall(PetscMalloc2(ncoo, &coo_i2, ncoo, &coo_j2));
7552:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_INT, coo_i, coo_i2 + ncoo_d + ncoo_oown)); /* put (i,j) of remote nonzeros at back */
7553:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_INT, coo_i, coo_i2 + ncoo_d + ncoo_oown));
7554:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_INT, coo_j, coo_j2 + ncoo_d + ncoo_oown));
7555:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_INT, coo_j, coo_j2 + ncoo_d + ncoo_oown));
7556:     PetscCall(PetscFree2(coo_i, coo_j));
7557:     /* allocate MPI send buffer to collect nonzero values to be sent to remote procs */
7558:     PetscCall(PetscSFMalloc(mmdata->sf, mmdata->mtype, ncoo_o * sizeof(PetscScalar), (void **)&mmdata->coo_w));
7559:     coo_i = coo_i2;
7560:     coo_j = coo_j2;
7561:   } else { /* no offproc values insertion */
7562:     ncoo = ncoo_d;
7563:     PetscCall(PetscMalloc2(ncoo, &coo_i, ncoo, &coo_j));

7565:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)C), &mmdata->sf));
7566:     PetscCall(PetscSFSetGraph(mmdata->sf, 0, 0, NULL, PETSC_OWN_POINTER, NULL, PETSC_OWN_POINTER));
7567:     PetscCall(PetscSFSetUp(mmdata->sf));
7568:   }
7569:   mmdata->hasoffproc = hasoffproc;

7571:   /* gather (i,j) of nonzeros inserted locally */
7572:   for (cp = 0, ncoo_d = 0; cp < mmdata->cp; cp++) {
7573:     Mat_SeqAIJ     *mm   = (Mat_SeqAIJ *)mp[cp]->data;
7574:     PetscInt       *coi  = coo_i + ncoo_d;
7575:     PetscInt       *coj  = coo_j + ncoo_d;
7576:     const PetscInt *jj   = mm->j;
7577:     const PetscInt *ii   = mm->i;
7578:     const PetscInt *cmap = cmapa[cp];
7579:     const PetscInt *rmap = rmapa[cp];
7580:     const PetscInt  mr   = mp[cp]->rmap->n;
7581:     const PetscInt  rs   = C->rmap->rstart;
7582:     const PetscInt  re   = C->rmap->rend;
7583:     const PetscInt  cs   = C->cmap->rstart;

7585:     if (mptmp[cp]) continue;
7586:     if (rmapt[cp] == 1) { /* consecutive rows */
7587:       /* fill coo_i */
7588:       for (i = 0; i < mr; i++) {
7589:         const PetscInt gr = i + rs;
7590:         for (j = ii[i]; j < ii[i + 1]; j++) coi[j] = gr;
7591:       }
7592:       /* fill coo_j */
7593:       if (!cmapt[cp]) { /* type-0, already global */
7594:         PetscCall(PetscArraycpy(coj, jj, mm->nz));
7595:       } else if (cmapt[cp] == 1) {                        /* type-1, local to global for consecutive columns of C */
7596:         for (j = 0; j < mm->nz; j++) coj[j] = jj[j] + cs; /* lid + col start */
7597:       } else {                                            /* type-2, local to global for sparse columns */
7598:         for (j = 0; j < mm->nz; j++) coj[j] = cmap[jj[j]];
7599:       }
7600:       ncoo_d += mm->nz;
7601:     } else if (rmapt[cp] == 2) { /* sparse rows */
7602:       for (i = 0; i < mr; i++) {
7603:         const PetscInt *jj = mm->j + ii[i];
7604:         const PetscInt  gr = rmap[i];
7605:         const PetscInt  nz = ii[i + 1] - ii[i];
7606:         if (gr >= rs && gr < re) { /* local rows */
7607:           for (j = ii[i]; j < ii[i + 1]; j++) *coi++ = gr;
7608:           if (!cmapt[cp]) { /* type-0, already global */
7609:             for (j = 0; j < nz; j++) *coj++ = jj[j];
7610:           } else if (cmapt[cp] == 1) { /* local to global for owned columns of C */
7611:             for (j = 0; j < nz; j++) *coj++ = jj[j] + cs;
7612:           } else { /* type-2, local to global for sparse columns */
7613:             for (j = 0; j < nz; j++) *coj++ = cmap[jj[j]];
7614:           }
7615:           ncoo_d += nz;
7616:         }
7617:       }
7618:     }
7619:   }
7620:   if (glob) PetscCall(ISRestoreIndices(glob, &globidx));
7621:   PetscCall(ISDestroy(&glob));
7622:   if (P_oth_l2g) PetscCall(ISLocalToGlobalMappingRestoreIndices(P_oth_l2g, &P_oth_idx));
7623:   PetscCall(ISLocalToGlobalMappingDestroy(&P_oth_l2g));
7624:   /* allocate an array to store all nonzeros (inserted locally or remotely) belonging to this proc */
7625:   PetscCall(PetscSFMalloc(mmdata->sf, mmdata->mtype, ncoo * sizeof(PetscScalar), (void **)&mmdata->coo_v));

7627:   /* set block sizes */
7628:   A = product->A;
7629:   P = product->B;
7630:   switch (ptype) {
7631:   case MATPRODUCT_PtAP:
7632:     PetscCall(MatSetBlockSizes(C, P->cmap->bs, P->cmap->bs));
7633:     break;
7634:   case MATPRODUCT_RARt:
7635:     PetscCall(MatSetBlockSizes(C, P->rmap->bs, P->rmap->bs));
7636:     break;
7637:   case MATPRODUCT_ABC:
7638:     PetscCall(MatSetBlockSizesFromMats(C, A, product->C));
7639:     break;
7640:   case MATPRODUCT_AB:
7641:     PetscCall(MatSetBlockSizesFromMats(C, A, P));
7642:     break;
7643:   case MATPRODUCT_AtB:
7644:     PetscCall(MatSetBlockSizes(C, A->cmap->bs, P->cmap->bs));
7645:     break;
7646:   case MATPRODUCT_ABt:
7647:     PetscCall(MatSetBlockSizes(C, A->rmap->bs, P->rmap->bs));
7648:     break;
7649:   default:
7650:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for ProductType %s", MatProductTypes[ptype]);
7651:   }

7653:   /* preallocate with COO data */
7654:   PetscCall(MatSetPreallocationCOO(C, ncoo, coo_i, coo_j));
7655:   PetscCall(PetscFree2(coo_i, coo_j));
7656:   PetscFunctionReturn(PETSC_SUCCESS);
7657: }

7659: PetscErrorCode MatProductSetFromOptions_MPIAIJBACKEND(Mat mat)
7660: {
7661:   Mat_Product *product = mat->product;
7662: #if PetscDefined(HAVE_DEVICE)
7663:   PetscBool match  = PETSC_FALSE;
7664:   PetscBool usecpu = PETSC_FALSE;
7665: #else
7666:   PetscBool match = PETSC_TRUE;
7667: #endif

7669:   PetscFunctionBegin;
7670:   MatCheckProduct(mat, 1);
7671: #if PetscDefined(HAVE_DEVICE)
7672:   if (!product->A->boundtocpu && !product->B->boundtocpu) PetscCall(PetscObjectTypeCompare((PetscObject)product->B, ((PetscObject)product->A)->type_name, &match));
7673:   if (match) { /* we can always fallback to the CPU if requested */
7674:     switch (product->type) {
7675:     case MATPRODUCT_AB:
7676:       if (product->api_user) {
7677:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatMatMult", "Mat");
7678:         PetscCall(PetscOptionsBool("-matmatmult_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
7679:         PetscOptionsEnd();
7680:       } else {
7681:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AB", "Mat");
7682:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
7683:         PetscOptionsEnd();
7684:       }
7685:       break;
7686:     case MATPRODUCT_AtB:
7687:       if (product->api_user) {
7688:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatTransposeMatMult", "Mat");
7689:         PetscCall(PetscOptionsBool("-mattransposematmult_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
7690:         PetscOptionsEnd();
7691:       } else {
7692:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AtB", "Mat");
7693:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
7694:         PetscOptionsEnd();
7695:       }
7696:       break;
7697:     case MATPRODUCT_PtAP:
7698:       if (product->api_user) {
7699:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatPtAP", "Mat");
7700:         PetscCall(PetscOptionsBool("-matptap_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
7701:         PetscOptionsEnd();
7702:       } else {
7703:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_PtAP", "Mat");
7704:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
7705:         PetscOptionsEnd();
7706:       }
7707:       break;
7708:     default:
7709:       break;
7710:     }
7711:     match = (PetscBool)!usecpu;
7712:   }
7713: #endif
7714:   if (match) {
7715:     switch (product->type) {
7716:     case MATPRODUCT_AB:
7717:     case MATPRODUCT_AtB:
7718:     case MATPRODUCT_PtAP:
7719:       mat->ops->productsymbolic = MatProductSymbolic_MPIAIJBACKEND;
7720:       break;
7721:     default:
7722:       break;
7723:     }
7724:   }
7725:   /* fallback to MPIAIJ ops */
7726:   if (!mat->ops->productsymbolic) PetscCall(MatProductSetFromOptions_MPIAIJ(mat));
7727:   PetscFunctionReturn(PETSC_SUCCESS);
7728: }

7730: /*
7731:    Produces a set of block column indices of the matrix row, one for each block represented in the original row

7733:    n - the number of block indices in cc[]
7734:    cc - the block indices (must be large enough to contain the indices)
7735: */
7736: static inline PetscErrorCode MatCollapseRow(Mat Amat, PetscInt row, PetscInt bs, PetscInt *n, PetscInt *cc)
7737: {
7738:   PetscInt        cnt = -1, nidx, j;
7739:   const PetscInt *idx;

7741:   PetscFunctionBegin;
7742:   PetscCall(MatGetRow(Amat, row, &nidx, &idx, NULL));
7743:   if (nidx) {
7744:     cnt     = 0;
7745:     cc[cnt] = idx[0] / bs;
7746:     for (j = 1; j < nidx; j++) {
7747:       if (cc[cnt] < idx[j] / bs) cc[++cnt] = idx[j] / bs;
7748:     }
7749:   }
7750:   PetscCall(MatRestoreRow(Amat, row, &nidx, &idx, NULL));
7751:   *n = cnt + 1;
7752:   PetscFunctionReturn(PETSC_SUCCESS);
7753: }

7755: /*
7756:     Produces a set of block column indices of the matrix block row, one for each block represented in the original set of rows

7758:     ncollapsed - the number of block indices
7759:     collapsed - the block indices (must be large enough to contain the indices)
7760: */
7761: static inline PetscErrorCode MatCollapseRows(Mat Amat, PetscInt start, PetscInt bs, PetscInt *w0, PetscInt *w1, PetscInt *w2, PetscInt *ncollapsed, PetscInt **collapsed)
7762: {
7763:   PetscInt i, nprev, *cprev = w0, ncur = 0, *ccur = w1, *merged = w2, *cprevtmp;

7765:   PetscFunctionBegin;
7766:   PetscCall(MatCollapseRow(Amat, start, bs, &nprev, cprev));
7767:   for (i = start + 1; i < start + bs; i++) {
7768:     PetscCall(MatCollapseRow(Amat, i, bs, &ncur, ccur));
7769:     PetscCall(PetscMergeIntArray(nprev, cprev, ncur, ccur, &nprev, &merged));
7770:     cprevtmp = cprev;
7771:     cprev    = merged;
7772:     merged   = cprevtmp;
7773:   }
7774:   *ncollapsed = nprev;
7775:   if (collapsed) *collapsed = cprev;
7776:   PetscFunctionReturn(PETSC_SUCCESS);
7777: }

7779: // PetscClangLinter pragma disable: -fdoc-sowing-chars
7780: /*
7781:   MatCreateGraph_Simple_AIJ - create simple scalar matrix (graph) from potentially blocked matrix

7783:   Input Parameters:
7784: + Amat       - matrix
7785: . symmetrize - make the result symmetric
7786: . scale      - scale with diagonal
7787: . filter     - threshold for filter
7788: . index_size - length of `index`
7789: - index      - indices of unknown purpose

7791:   Output Parameter:
7792: . a_Gmat - output scalar graph >= 0

7794:   Level: developer

7796: .seealso: `MATAIJ`
7797: */
7798: PETSC_INTERN PetscErrorCode MatCreateGraph_Simple_AIJ(Mat Amat, PetscBool symmetrize, PetscBool scale, PetscReal filter, PetscInt index_size, PetscInt index[], Mat *a_Gmat)
7799: {
7800:   PetscInt  Istart, Iend, Ii, jj, kk, ncols, nloc, NN, MM, bs;
7801:   MPI_Comm  comm;
7802:   Mat       Gmat;
7803:   PetscBool ismpiaij, isseqaij;
7804:   Mat       a, b, c;
7805:   MatType   jtype;

7807:   PetscFunctionBegin;
7808:   PetscCall(PetscObjectGetComm((PetscObject)Amat, &comm));
7809:   PetscCall(MatGetOwnershipRange(Amat, &Istart, &Iend));
7810:   PetscCall(MatGetSize(Amat, &MM, &NN));
7811:   PetscCall(MatGetBlockSize(Amat, &bs));
7812:   nloc = (Iend - Istart) / bs;

7814:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)Amat, MATSEQAIJ, &isseqaij));
7815:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)Amat, MATMPIAIJ, &ismpiaij));
7816:   PetscCheck(isseqaij || ismpiaij, comm, PETSC_ERR_USER, "Require (MPI)AIJ matrix type");

7818:   /* TODO GPU: these calls are potentially expensive if matrices are large and we want to use the GPU */
7819:   /* A solution consists in providing a new API, MatAIJGetCollapsedAIJ, and each class can provide a fast
7820:      implementation */
7821:   if (bs > 1) {
7822:     PetscCall(MatGetType(Amat, &jtype));
7823:     PetscCall(MatCreate(comm, &Gmat));
7824:     PetscCall(MatSetType(Gmat, jtype));
7825:     PetscCall(MatSetSizes(Gmat, nloc, nloc, PETSC_DETERMINE, PETSC_DETERMINE));
7826:     PetscCall(MatSetBlockSizes(Gmat, 1, 1));
7827:     if (isseqaij || ((Mat_MPIAIJ *)Amat->data)->garray) {
7828:       PetscInt  *d_nnz, *o_nnz;
7829:       MatScalar *aa, val, *AA;
7830:       PetscInt  *aj, *ai, *AJ, nc, nmax = 0;

7832:       if (isseqaij) {
7833:         a = Amat;
7834:         b = NULL;
7835:       } else {
7836:         Mat_MPIAIJ *d = (Mat_MPIAIJ *)Amat->data;
7837:         a             = d->A;
7838:         b             = d->B;
7839:       }
7840:       PetscCall(PetscInfo(Amat, "New bs>1 Graph. nloc=%" PetscInt_FMT "\n", nloc));
7841:       PetscCall(PetscMalloc2(nloc, &d_nnz, (isseqaij ? 0 : nloc), &o_nnz));
7842:       for (c = a, kk = 0; c && kk < 2; c = b, kk++) {
7843:         PetscInt       *nnz = (c == a) ? d_nnz : o_nnz;
7844:         const PetscInt *cols1, *cols2;

7846:         for (PetscInt brow = 0, nc1, nc2, ok = 1; brow < nloc * bs; brow += bs) { // block rows
7847:           PetscCall(MatGetRow(c, brow, &nc2, &cols2, NULL));
7848:           nnz[brow / bs] = nc2 / bs;
7849:           if (nc2 % bs) ok = 0;
7850:           if (nnz[brow / bs] > nmax) nmax = nnz[brow / bs];
7851:           for (PetscInt ii = 1; ii < bs; ii++) { // check for non-dense blocks
7852:             PetscCall(MatGetRow(c, brow + ii, &nc1, &cols1, NULL));
7853:             if (nc1 != nc2) ok = 0;
7854:             else {
7855:               for (PetscInt jj = 0; jj < nc1 && ok == 1; jj++) {
7856:                 if (cols1[jj] != cols2[jj]) ok = 0;
7857:                 if (cols1[jj] % bs != jj % bs) ok = 0;
7858:               }
7859:             }
7860:             PetscCall(MatRestoreRow(c, brow + ii, &nc1, &cols1, NULL));
7861:           }
7862:           PetscCall(MatRestoreRow(c, brow, &nc2, &cols2, NULL));
7863:           if (!ok) {
7864:             PetscCall(PetscFree2(d_nnz, o_nnz));
7865:             PetscCall(PetscInfo(Amat, "Found sparse blocks - revert to slow method\n"));
7866:             goto old_bs;
7867:           }
7868:         }
7869:       }
7870:       PetscCall(MatSeqAIJSetPreallocation(Gmat, 0, d_nnz));
7871:       PetscCall(MatMPIAIJSetPreallocation(Gmat, 0, d_nnz, 0, o_nnz));
7872:       PetscCall(PetscFree2(d_nnz, o_nnz));
7873:       PetscCall(PetscMalloc2(nmax, &AA, nmax, &AJ));
7874:       // diag
7875:       for (PetscInt brow = 0, n, grow; brow < nloc * bs; brow += bs) { // block rows
7876:         Mat_SeqAIJ *aseq = (Mat_SeqAIJ *)a->data;

7878:         ai = aseq->i;
7879:         n  = ai[brow + 1] - ai[brow];
7880:         aj = aseq->j + ai[brow];
7881:         for (PetscInt k = 0; k < n; k += bs) {   // block columns
7882:           AJ[k / bs] = aj[k] / bs + Istart / bs; // diag starts at (Istart,Istart)
7883:           val        = 0;
7884:           if (index_size == 0) {
7885:             for (PetscInt ii = 0; ii < bs; ii++) { // rows in block
7886:               aa = aseq->a + ai[brow + ii] + k;
7887:               for (PetscInt jj = 0; jj < bs; jj++) {    // columns in block
7888:                 val += PetscAbs(PetscRealPart(aa[jj])); // a sort of norm
7889:               }
7890:             }
7891:           } else {                                            // use (index,index) value if provided
7892:             for (PetscInt iii = 0; iii < index_size; iii++) { // rows in block
7893:               PetscInt ii = index[iii];
7894:               aa          = aseq->a + ai[brow + ii] + k;
7895:               for (PetscInt jjj = 0; jjj < index_size; jjj++) { // columns in block
7896:                 PetscInt jj = index[jjj];
7897:                 val += PetscAbs(PetscRealPart(aa[jj]));
7898:               }
7899:             }
7900:           }
7901:           PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs (%" PetscInt_FMT ") >= nmax (%" PetscInt_FMT ")", k / bs, nmax);
7902:           AA[k / bs] = val;
7903:         }
7904:         grow = Istart / bs + brow / bs;
7905:         PetscCall(MatSetValues(Gmat, 1, &grow, n / bs, AJ, AA, ADD_VALUES));
7906:       }
7907:       // off-diag
7908:       if (ismpiaij) {
7909:         Mat_MPIAIJ        *aij = (Mat_MPIAIJ *)Amat->data;
7910:         const PetscScalar *vals;
7911:         const PetscInt    *cols, *garray = aij->garray;

7913:         PetscCheck(garray, PETSC_COMM_SELF, PETSC_ERR_USER, "No garray ?");
7914:         for (PetscInt brow = 0, grow; brow < nloc * bs; brow += bs) { // block rows
7915:           PetscCall(MatGetRow(b, brow, &ncols, &cols, NULL));
7916:           for (PetscInt k = 0, cidx = 0; k < ncols; k += bs, cidx++) {
7917:             PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs >= nmax");
7918:             AA[k / bs] = 0;
7919:             AJ[cidx]   = garray[cols[k]] / bs;
7920:           }
7921:           nc = ncols / bs;
7922:           PetscCall(MatRestoreRow(b, brow, &ncols, &cols, NULL));
7923:           if (index_size == 0) {
7924:             for (PetscInt ii = 0; ii < bs; ii++) { // rows in block
7925:               PetscCall(MatGetRow(b, brow + ii, &ncols, &cols, &vals));
7926:               for (PetscInt k = 0; k < ncols; k += bs) {
7927:                 for (PetscInt jj = 0; jj < bs; jj++) { // cols in block
7928:                   PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs (%" PetscInt_FMT ") >= nmax (%" PetscInt_FMT ")", k / bs, nmax);
7929:                   AA[k / bs] += PetscAbs(PetscRealPart(vals[k + jj]));
7930:                 }
7931:               }
7932:               PetscCall(MatRestoreRow(b, brow + ii, &ncols, &cols, &vals));
7933:             }
7934:           } else {                                            // use (index,index) value if provided
7935:             for (PetscInt iii = 0; iii < index_size; iii++) { // rows in block
7936:               PetscInt ii = index[iii];
7937:               PetscCall(MatGetRow(b, brow + ii, &ncols, &cols, &vals));
7938:               for (PetscInt k = 0; k < ncols; k += bs) {
7939:                 for (PetscInt jjj = 0; jjj < index_size; jjj++) { // cols in block
7940:                   PetscInt jj = index[jjj];
7941:                   AA[k / bs] += PetscAbs(PetscRealPart(vals[k + jj]));
7942:                 }
7943:               }
7944:               PetscCall(MatRestoreRow(b, brow + ii, &ncols, &cols, &vals));
7945:             }
7946:           }
7947:           grow = Istart / bs + brow / bs;
7948:           PetscCall(MatSetValues(Gmat, 1, &grow, nc, AJ, AA, ADD_VALUES));
7949:         }
7950:       }
7951:       PetscCall(MatAssemblyBegin(Gmat, MAT_FINAL_ASSEMBLY));
7952:       PetscCall(MatAssemblyEnd(Gmat, MAT_FINAL_ASSEMBLY));
7953:       PetscCall(PetscFree2(AA, AJ));
7954:     } else {
7955:       const PetscScalar *vals;
7956:       const PetscInt    *idx;
7957:       PetscInt          *d_nnz, *o_nnz, *w0, *w1, *w2;
7958:     old_bs:
7959:       /*
7960:        Determine the preallocation needed for the scalar matrix derived from the vector matrix.
7961:        */
7962:       PetscCall(PetscInfo(Amat, "OLD bs>1 CreateGraph\n"));
7963:       PetscCall(PetscMalloc2(nloc, &d_nnz, (isseqaij ? 0 : nloc), &o_nnz));
7964:       if (isseqaij) {
7965:         PetscInt max_d_nnz;

7967:         /*
7968:          Determine exact preallocation count for (sequential) scalar matrix
7969:          */
7970:         PetscCall(MatSeqAIJGetMaxRowNonzeros(Amat, &max_d_nnz));
7971:         max_d_nnz = PetscMin(nloc, bs * max_d_nnz);
7972:         PetscCall(PetscMalloc3(max_d_nnz, &w0, max_d_nnz, &w1, max_d_nnz, &w2));
7973:         for (Ii = 0, jj = 0; Ii < Iend; Ii += bs, jj++) PetscCall(MatCollapseRows(Amat, Ii, bs, w0, w1, w2, &d_nnz[jj], NULL));
7974:         PetscCall(PetscFree3(w0, w1, w2));
7975:       } else if (ismpiaij) {
7976:         Mat             Daij, Oaij;
7977:         const PetscInt *garray;
7978:         PetscInt        max_d_nnz;

7980:         PetscCall(MatMPIAIJGetSeqAIJ(Amat, &Daij, &Oaij, &garray));
7981:         /*
7982:          Determine exact preallocation count for diagonal block portion of scalar matrix
7983:          */
7984:         PetscCall(MatSeqAIJGetMaxRowNonzeros(Daij, &max_d_nnz));
7985:         max_d_nnz = PetscMin(nloc, bs * max_d_nnz);
7986:         PetscCall(PetscMalloc3(max_d_nnz, &w0, max_d_nnz, &w1, max_d_nnz, &w2));
7987:         for (Ii = 0, jj = 0; Ii < Iend - Istart; Ii += bs, jj++) PetscCall(MatCollapseRows(Daij, Ii, bs, w0, w1, w2, &d_nnz[jj], NULL));
7988:         PetscCall(PetscFree3(w0, w1, w2));
7989:         /*
7990:          Over estimate (usually grossly over), preallocation count for off-diagonal portion of scalar matrix
7991:          */
7992:         for (Ii = 0, jj = 0; Ii < Iend - Istart; Ii += bs, jj++) {
7993:           o_nnz[jj] = 0;
7994:           for (kk = 0; kk < bs; kk++) { /* rows that get collapsed to a single row */
7995:             PetscCall(MatGetRow(Oaij, Ii + kk, &ncols, NULL, NULL));
7996:             o_nnz[jj] += ncols;
7997:             PetscCall(MatRestoreRow(Oaij, Ii + kk, &ncols, NULL, NULL));
7998:           }
7999:           if (o_nnz[jj] > (NN / bs - nloc)) o_nnz[jj] = NN / bs - nloc;
8000:         }
8001:       } else SETERRQ(comm, PETSC_ERR_USER, "Require AIJ matrix type");
8002:       /* get scalar copy (norms) of matrix */
8003:       PetscCall(MatSeqAIJSetPreallocation(Gmat, 0, d_nnz));
8004:       PetscCall(MatMPIAIJSetPreallocation(Gmat, 0, d_nnz, 0, o_nnz));
8005:       PetscCall(PetscFree2(d_nnz, o_nnz));
8006:       for (Ii = Istart; Ii < Iend; Ii++) {
8007:         PetscInt dest_row = Ii / bs;

8009:         PetscCall(MatGetRow(Amat, Ii, &ncols, &idx, &vals));
8010:         for (jj = 0; jj < ncols; jj++) {
8011:           PetscInt    dest_col = idx[jj] / bs;
8012:           PetscScalar sv       = PetscAbs(PetscRealPart(vals[jj]));

8014:           PetscCall(MatSetValues(Gmat, 1, &dest_row, 1, &dest_col, &sv, ADD_VALUES));
8015:         }
8016:         PetscCall(MatRestoreRow(Amat, Ii, &ncols, &idx, &vals));
8017:       }
8018:       PetscCall(MatAssemblyBegin(Gmat, MAT_FINAL_ASSEMBLY));
8019:       PetscCall(MatAssemblyEnd(Gmat, MAT_FINAL_ASSEMBLY));
8020:     }
8021:   } else {
8022:     if (symmetrize || filter >= 0 || scale) PetscCall(MatDuplicate(Amat, MAT_COPY_VALUES, &Gmat));
8023:     else {
8024:       Gmat = Amat;
8025:       PetscCall(PetscObjectReference((PetscObject)Gmat));
8026:     }
8027:     if (isseqaij) {
8028:       a = Gmat;
8029:       b = NULL;
8030:     } else {
8031:       Mat_MPIAIJ *d = (Mat_MPIAIJ *)Gmat->data;
8032:       a             = d->A;
8033:       b             = d->B;
8034:     }
8035:     if (filter >= 0 || scale) {
8036:       /* take absolute value of each entry */
8037:       for (c = a, kk = 0; c && kk < 2; c = b, kk++) {
8038:         MatInfo      info;
8039:         PetscScalar *avals;

8041:         PetscCall(MatGetInfo(c, MAT_LOCAL, &info));
8042:         PetscCall(MatSeqAIJGetArray(c, &avals));
8043:         for (int jj = 0; jj < info.nz_used; jj++) avals[jj] = PetscAbsScalar(avals[jj]);
8044:         PetscCall(MatSeqAIJRestoreArray(c, &avals));
8045:       }
8046:     }
8047:   }
8048:   if (symmetrize) {
8049:     PetscBool isset, issym;

8051:     PetscCall(MatIsSymmetricKnown(Amat, &isset, &issym));
8052:     if (!isset || !issym) {
8053:       Mat matTrans;

8055:       PetscCall(MatTranspose(Gmat, MAT_INITIAL_MATRIX, &matTrans));
8056:       PetscCall(MatAXPY(Gmat, 1.0, matTrans, Gmat->structurally_symmetric == PETSC_BOOL3_TRUE ? SAME_NONZERO_PATTERN : DIFFERENT_NONZERO_PATTERN));
8057:       PetscCall(MatDestroy(&matTrans));
8058:     }
8059:     PetscCall(MatSetOption(Gmat, MAT_SYMMETRIC, PETSC_TRUE));
8060:   } else if (Amat != Gmat) PetscCall(MatPropagateSymmetryOptions(Amat, Gmat));
8061:   if (scale) {
8062:     /* scale c for all diagonal values = 1 or -1 */
8063:     Vec diag;

8065:     PetscCall(MatCreateVecs(Gmat, &diag, NULL));
8066:     PetscCall(MatGetDiagonal(Gmat, diag));
8067:     PetscCall(VecReciprocal(diag));
8068:     PetscCall(VecSqrtAbs(diag));
8069:     PetscCall(MatDiagonalScale(Gmat, diag, diag));
8070:     PetscCall(VecDestroy(&diag));
8071:   }
8072:   PetscCall(MatViewFromOptions(Gmat, NULL, "-mat_graph_view"));
8073:   if (filter >= 0) {
8074:     PetscCall(MatFilter(Gmat, filter, PETSC_TRUE, PETSC_TRUE));
8075:     PetscCall(MatViewFromOptions(Gmat, NULL, "-mat_filter_graph_view"));
8076:   }
8077:   *a_Gmat = Gmat;
8078:   PetscFunctionReturn(PETSC_SUCCESS);
8079: }

8081: PETSC_INTERN PetscErrorCode MatGetCurrentMemType_MPIAIJ(Mat A, PetscMemType *memtype)
8082: {
8083:   Mat_MPIAIJ  *mpiaij = (Mat_MPIAIJ *)A->data;
8084:   PetscMemType mD = PETSC_MEMTYPE_HOST, mO = PETSC_MEMTYPE_HOST;

8086:   PetscFunctionBegin;
8087:   if (mpiaij->A) PetscCall(MatGetCurrentMemType(mpiaij->A, &mD));
8088:   if (mpiaij->B) PetscCall(MatGetCurrentMemType(mpiaij->B, &mO));
8089:   *memtype = (mD == mO) ? mD : PETSC_MEMTYPE_HOST;
8090:   PetscFunctionReturn(PETSC_SUCCESS);
8091: }

8093: /*
8094:     Special version for direct calls from Fortran
8095: */

8097: /* Change these macros so can be used in void function */
8098: /* Identical to PetscCallVoid, except it assigns to *_ierr */
8099: #undef PetscCall
8100: #define PetscCall(...) \
8101:   do { \
8102:     PetscErrorCode ierr_msv_mpiaij = __VA_ARGS__; \
8103:     if (PetscUnlikely(ierr_msv_mpiaij)) { \
8104:       *_ierr = PetscError(PETSC_COMM_SELF, __LINE__, PETSC_FUNCTION_NAME, __FILE__, ierr_msv_mpiaij, PETSC_ERROR_REPEAT, " "); \
8105:       return; \
8106:     } \
8107:   } while (0)

8109: #undef SETERRQ
8110: #define SETERRQ(comm, ierr, ...) \
8111:   do { \
8112:     *_ierr = PetscError(comm, __LINE__, PETSC_FUNCTION_NAME, __FILE__, ierr, PETSC_ERROR_INITIAL, __VA_ARGS__); \
8113:     return; \
8114:   } while (0)

8116: #if PetscDefined(HAVE_FORTRAN_CAPS)
8117:   #define matsetvaluesmpiaij_ MATSETVALUESMPIAIJ
8118: #elif !PetscDefined(HAVE_FORTRAN_UNDERSCORE)
8119:   #define matsetvaluesmpiaij_ matsetvaluesmpiaij
8120: #else
8121: #endif
8122: PETSC_EXTERN void matsetvaluesmpiaij_(Mat *mmat, PetscInt *mm, const PetscInt im[], PetscInt *mn, const PetscInt in[], const PetscScalar v[], InsertMode *maddv, PetscErrorCode *_ierr)
8123: {
8124:   Mat         mat = *mmat;
8125:   PetscInt    m = *mm, n = *mn;
8126:   InsertMode  addv = *maddv;
8127:   Mat_MPIAIJ *aij  = (Mat_MPIAIJ *)mat->data;
8128:   PetscScalar value;

8130:   MatCheckPreallocated(mat, 1);
8131:   if (mat->insertmode == NOT_SET_VALUES) mat->insertmode = addv;
8132:   else PetscCheck(mat->insertmode == addv, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Cannot mix add values and insert values");
8133:   {
8134:     PetscInt  i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
8135:     PetscInt  cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
8136:     PetscBool roworiented = aij->roworiented;

8138:     /* Some Variables required in the macro */
8139:     Mat         A     = aij->A;
8140:     Mat_SeqAIJ *a     = (Mat_SeqAIJ *)A->data;
8141:     PetscInt   *aimax = a->imax, *ai = a->i, *ailen = a->ilen, *aj = a->j;
8142:     MatScalar  *aa;
8143:     PetscBool   ignorezeroentries = ((a->ignorezeroentries && (addv == ADD_VALUES)) ? PETSC_TRUE : PETSC_FALSE);
8144:     Mat         B                 = aij->B;
8145:     Mat_SeqAIJ *b                 = (Mat_SeqAIJ *)B->data;
8146:     PetscInt   *bimax = b->imax, *bi = b->i, *bilen = b->ilen, *bj = b->j, bm = aij->B->rmap->n, am = aij->A->rmap->n;
8147:     MatScalar  *ba;
8148:     /* This variable below is only for the PETSC_HAVE_VIENNACL or PETSC_HAVE_CUDA cases, but we define it in all cases because we
8149:      * cannot use "#if defined" inside a macro. */
8150:     PETSC_UNUSED PetscBool inserted = PETSC_FALSE;

8152:     PetscInt  *rp1, *rp2, ii, nrow1, nrow2, _i, rmax1, rmax2, N, low1, high1, low2, high2, t, lastcol1, lastcol2;
8153:     PetscInt   nonew = a->nonew;
8154:     MatScalar *ap1, *ap2;

8156:     PetscFunctionBegin;
8157:     PetscCall(MatSeqAIJGetArray(A, &aa));
8158:     PetscCall(MatSeqAIJGetArray(B, &ba));
8159:     for (i = 0; i < m; i++) {
8160:       if (im[i] < 0) continue;
8161:       PetscCheck(im[i] < mat->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Row too large: row %" PetscInt_FMT " max %" PetscInt_FMT, im[i], mat->rmap->N - 1);
8162:       if (im[i] >= rstart && im[i] < rend) {
8163:         row      = im[i] - rstart;
8164:         lastcol1 = -1;
8165:         rp1      = aj + ai[row];
8166:         ap1      = aa + ai[row];
8167:         rmax1    = aimax[row];
8168:         nrow1    = ailen[row];
8169:         low1     = 0;
8170:         high1    = nrow1;
8171:         lastcol2 = -1;
8172:         rp2      = bj + bi[row];
8173:         ap2      = ba + bi[row];
8174:         rmax2    = bimax[row];
8175:         nrow2    = bilen[row];
8176:         low2     = 0;
8177:         high2    = nrow2;

8179:         for (j = 0; j < n; j++) {
8180:           if (roworiented) value = v[i * n + j];
8181:           else value = v[i + j * m];
8182:           if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES) && im[i] != in[j]) continue;
8183:           if (in[j] >= cstart && in[j] < cend) {
8184:             col = in[j] - cstart;
8185:             MatSetValues_SeqAIJ_A_Private(row, col, value, addv, im[i], in[j]);
8186:           } else if (in[j] < 0) continue;
8187:           else if (PetscUnlikelyDebug(in[j] >= mat->cmap->N)) {
8188:             SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column too large: col %" PetscInt_FMT " max %" PetscInt_FMT, in[j], mat->cmap->N - 1);
8189:           } else {
8190:             if (mat->was_assembled) {
8191:               if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
8192: #if PetscDefined(USE_CTABLE)
8193:               PetscCall(PetscHMapIGetWithDefault(aij->colmap, in[j] + 1, 0, &col));
8194:               col--;
8195: #else
8196:               col = aij->colmap[in[j]] - 1;
8197: #endif
8198:               if (col < 0 && !((Mat_SeqAIJ *)aij->A->data)->nonew) {
8199:                 PetscCall(MatDisAssemble_MPIAIJ(mat, PETSC_FALSE));
8200:                 col = in[j];
8201:                 /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
8202:                 B        = aij->B;
8203:                 b        = (Mat_SeqAIJ *)B->data;
8204:                 bimax    = b->imax;
8205:                 bi       = b->i;
8206:                 bilen    = b->ilen;
8207:                 bj       = b->j;
8208:                 rp2      = bj + bi[row];
8209:                 ap2      = ba + bi[row];
8210:                 rmax2    = bimax[row];
8211:                 nrow2    = bilen[row];
8212:                 low2     = 0;
8213:                 high2    = nrow2;
8214:                 bm       = aij->B->rmap->n;
8215:                 ba       = b->a;
8216:                 inserted = PETSC_FALSE;
8217:               }
8218:             } else col = in[j];
8219:             MatSetValues_SeqAIJ_B_Private(row, col, value, addv, im[i], in[j]);
8220:           }
8221:         }
8222:       } else if (!aij->donotstash) {
8223:         if (roworiented) {
8224:           PetscCall(MatStashValuesRow_Private(&mat->stash, im[i], n, in, v + i * n, (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
8225:         } else {
8226:           PetscCall(MatStashValuesCol_Private(&mat->stash, im[i], n, in, v + i, m, (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
8227:         }
8228:       }
8229:     }
8230:     PetscCall(MatSeqAIJRestoreArray(A, &aa));
8231:     PetscCall(MatSeqAIJRestoreArray(B, &ba));
8232:   }
8233:   PetscFunctionReturnVoid();
8234: }

8236: /* Undefining these here since they were redefined from their original definition above! No
8237:  * other PETSc functions should be defined past this point, as it is impossible to recover the
8238:  * original definitions */
8239: #undef PetscCall
8240: #undef SETERRQ