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 defined(PETSC_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, "MatIsTranspose_C", NULL));
 67:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetPreallocation_C", NULL));
 68:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatResetPreallocation_C", NULL));
 69:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatResetHash_C", NULL));
 70:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetPreallocationCSR_C", NULL));
 71:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatDiagonalScaleLocal_C", NULL));
 72:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpibaij_C", NULL));
 73:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpisbaij_C", NULL));
 74: #if defined(PETSC_HAVE_CUDA)
 75:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijcusparse_C", NULL));
 76: #endif
 77: #if defined(PETSC_HAVE_HIP)
 78:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijhipsparse_C", NULL));
 79: #endif
 80: #if defined(PETSC_HAVE_KOKKOS_KERNELS)
 81:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijkokkos_C", NULL));
 82: #endif
 83:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpidense_C", NULL));
 84: #if defined(PETSC_HAVE_ELEMENTAL)
 85:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_elemental_C", NULL));
 86: #endif
 87: #if defined(PETSC_HAVE_SCALAPACK)
 88:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_scalapack_C", NULL));
 89: #endif
 90: #if defined(PETSC_HAVE_HYPRE)
 91:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_hypre_C", NULL));
 92:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_transpose_mpiaij_mpiaij_C", NULL));
 93: #endif
 94:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_is_C", NULL));
 95:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_is_mpiaij_C", NULL));
 96:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_mpiaij_mpiaij_C", NULL));
 97:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetUseScalableIncreaseOverlap_C", NULL));
 98:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijperm_C", NULL));
 99:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijsell_C", NULL));
100: #if defined(PETSC_HAVE_MKL_SPARSE)
101:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijmkl_C", NULL));
102: #endif
103:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijcrl_C", NULL));
104:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_is_C", NULL));
105:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpisell_C", NULL));
106:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatSetPreallocationCOO_C", NULL));
107:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatSetValuesCOO_C", NULL));
108:   PetscFunctionReturn(PETSC_SUCCESS);
109: }

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

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

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

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

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

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

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

146:   Developer Note:
147:   Level: beginner

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

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

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

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

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

167:   Level: beginner

169: .seealso: [](ch_matrices), `Mat`, `MatCreateMPIAIJCRL`, `MATSEQAIJCRL`, `MATMPIAIJCRL`, `MATSEQAIJCRL`, `MATMPIAIJCRL`
170: M*/

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

176:   PetscFunctionBegin;
177: #if defined(PETSC_HAVE_CUDA) || defined(PETSC_HAVE_HIP) || defined(PETSC_HAVE_VIENNACL)
178:   A->boundtocpu = flg;
179: #endif
180:   if (a->A) PetscCall(MatBindToCPU(a->A, flg));
181:   if (a->B) PetscCall(MatBindToCPU(a->B, flg));

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

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

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

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

213:   PetscFunctionBegin;
214:   *keptrows = NULL;

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

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

277:   PetscFunctionBegin;
278:   PetscCall(MatHasCongruentLayouts(Y, &cong));
279:   if (Y->assembled && cong) {
280:     PetscCall(MatDiagonalSet(aij->A, D, is));
281:   } else {
282:     PetscCall(MatDiagonalSet_Default(Y, D, is));
283:   }
284:   PetscFunctionReturn(PETSC_SUCCESS);
285: }

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

292:   PetscFunctionBegin;
293:   *zrows = NULL;
294:   PetscCall(MatFindZeroDiagonals_SeqAIJ_Private(aij->A, &nrows, &rows));
295:   PetscCall(MatGetOwnershipRange(M, &rstart, NULL));
296:   for (i = 0; i < nrows; i++) rows[i] += rstart;
297:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)M), nrows, rows, PETSC_OWN_POINTER, zrows));
298:   PetscFunctionReturn(PETSC_SUCCESS);
299: }

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

310:   PetscFunctionBegin;
311:   PetscCall(MatGetSize(A, &m, &n));
312:   PetscCall(PetscCalloc1(n, &work));
313:   PetscCall(MatSeqAIJGetArrayRead(aij->A, &dummy));
314:   PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &dummy));
315:   PetscCall(MatSeqAIJGetArrayRead(aij->B, &dummy));
316:   PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &dummy));
317:   if (type == NORM_2) {
318:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) work[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i] * a_aij->a[i]);
319:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i] * b_aij->a[i]);
320:   } else if (type == NORM_1) {
321:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) work[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i]);
322:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i]);
323:   } else if (type == NORM_INFINITY) {
324:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) work[A->cmap->rstart + a_aij->j[i]] = PetscMax(PetscAbsScalar(a_aij->a[i]), work[A->cmap->rstart + a_aij->j[i]]);
325:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] = PetscMax(PetscAbsScalar(b_aij->a[i]), work[garray[b_aij->j[i]]]);
326:   } else if (type == REDUCTION_SUM_REALPART || type == REDUCTION_MEAN_REALPART) {
327:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) work[A->cmap->rstart + a_aij->j[i]] += PetscRealPart(a_aij->a[i]);
328:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] += PetscRealPart(b_aij->a[i]);
329:   } else if (type == REDUCTION_SUM_IMAGINARYPART || type == REDUCTION_MEAN_IMAGINARYPART) {
330:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) work[A->cmap->rstart + a_aij->j[i]] += PetscImaginaryPart(a_aij->a[i]);
331:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] += PetscImaginaryPart(b_aij->a[i]);
332:   } else SETERRQ(PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONG, "Unknown reduction type");
333:   if (type == NORM_INFINITY) {
334:     PetscCallMPI(MPIU_Allreduce(work, reductions, n, MPIU_REAL, MPIU_MAX, PetscObjectComm((PetscObject)A)));
335:   } else {
336:     PetscCallMPI(MPIU_Allreduce(work, reductions, n, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)A)));
337:   }
338:   PetscCall(PetscFree(work));
339:   if (type == NORM_2) {
340:     for (i = 0; i < n; i++) reductions[i] = PetscSqrtReal(reductions[i]);
341:   } else if (type == REDUCTION_MEAN_REALPART || type == REDUCTION_MEAN_IMAGINARYPART) {
342:     for (i = 0; i < n; i++) reductions[i] /= m;
343:   }
344:   PetscFunctionReturn(PETSC_SUCCESS);
345: }

347: static PetscErrorCode MatFindOffBlockDiagonalEntries_MPIAIJ(Mat A, IS *is)
348: {
349:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)A->data;
350:   IS              sis, gis;
351:   const PetscInt *isis, *igis;
352:   PetscInt        n, *iis, nsis, ngis, rstart, i;

354:   PetscFunctionBegin;
355:   PetscCall(MatFindOffBlockDiagonalEntries(a->A, &sis));
356:   PetscCall(MatFindNonzeroRows(a->B, &gis));
357:   PetscCall(ISGetSize(gis, &ngis));
358:   PetscCall(ISGetSize(sis, &nsis));
359:   PetscCall(ISGetIndices(sis, &isis));
360:   PetscCall(ISGetIndices(gis, &igis));

362:   PetscCall(PetscMalloc1(ngis + nsis, &iis));
363:   PetscCall(PetscArraycpy(iis, igis, ngis));
364:   PetscCall(PetscArraycpy(iis + ngis, isis, nsis));
365:   n = ngis + nsis;
366:   PetscCall(PetscSortRemoveDupsInt(&n, iis));
367:   PetscCall(MatGetOwnershipRange(A, &rstart, NULL));
368:   for (i = 0; i < n; i++) iis[i] += rstart;
369:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)A), n, iis, PETSC_OWN_POINTER, is));

371:   PetscCall(ISRestoreIndices(sis, &isis));
372:   PetscCall(ISRestoreIndices(gis, &igis));
373:   PetscCall(ISDestroy(&sis));
374:   PetscCall(ISDestroy(&gis));
375:   PetscFunctionReturn(PETSC_SUCCESS);
376: }

378: /*
379:   Local utility routine that creates a mapping from the global column
380: number to the local number in the off-diagonal part of the local
381: storage of the matrix.  When PETSC_USE_CTABLE is used this is scalable at
382: a slightly higher hash table cost; without it it is not scalable (each processor
383: has an order N integer array but is fast to access.
384: */
385: PetscErrorCode MatCreateColmap_MPIAIJ_Private(Mat mat)
386: {
387:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
388:   PetscInt    n   = aij->B->cmap->n, i;

390:   PetscFunctionBegin;
391:   PetscCheck(!n || aij->garray, PETSC_COMM_SELF, PETSC_ERR_PLIB, "MPIAIJ Matrix was assembled but is missing garray");
392: #if defined(PETSC_USE_CTABLE)
393:   PetscCall(PetscHMapICreateWithSize(n, &aij->colmap));
394:   for (i = 0; i < n; i++) PetscCall(PetscHMapISet(aij->colmap, aij->garray[i] + 1, i + 1));
395: #else
396:   PetscCall(PetscCalloc1(mat->cmap->N + 1, &aij->colmap));
397:   for (i = 0; i < n; i++) aij->colmap[aij->garray[i]] = i + 1;
398: #endif
399:   PetscFunctionReturn(PETSC_SUCCESS);
400: }

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

447: #define MatSetValues_SeqAIJ_B_Private(row, col, value, addv, orow, ocol) \
448:   do { \
449:     if (col <= lastcol2) low2 = 0; \
450:     else high2 = nrow2; \
451:     lastcol2 = col; \
452:     while (high2 - low2 > 5) { \
453:       t = (low2 + high2) / 2; \
454:       if (rp2[t] > col) high2 = t; \
455:       else low2 = t; \
456:     } \
457:     for (_i = low2; _i < high2; _i++) { \
458:       if (rp2[_i] > col) break; \
459:       if (rp2[_i] == col) { \
460:         if (addv == ADD_VALUES) { \
461:           ap2[_i] += value; \
462:           (void)PetscLogFlops(1.0); \
463:         } else ap2[_i] = value; \
464:         goto b_noinsert; \
465:       } \
466:     } \
467:     if (value == 0.0 && ignorezeroentries) { \
468:       low2  = 0; \
469:       high2 = nrow2; \
470:       goto b_noinsert; \
471:     } \
472:     if (nonew == 1) { \
473:       low2  = 0; \
474:       high2 = nrow2; \
475:       goto b_noinsert; \
476:     } \
477:     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); \
478:     MatSeqXAIJReallocateAIJ(B, bm, 1, nrow2, row, col, rmax2, ba, bi, bj, rp2, ap2, bimax, nonew, MatScalar); \
479:     N = nrow2++ - 1; \
480:     b->nz++; \
481:     high2++; \
482:     /* shift up all the later entries in this row */ \
483:     PetscCall(PetscArraymove(rp2 + _i + 1, rp2 + _i, N - _i + 1)); \
484:     PetscCall(PetscArraymove(ap2 + _i + 1, ap2 + _i, N - _i + 1)); \
485:     rp2[_i] = col; \
486:     ap2[_i] = value; \
487:   b_noinsert:; \
488:     bilen[row] = nrow2; \
489:   } while (0)

491: static PetscErrorCode MatSetValuesRow_MPIAIJ(Mat A, PetscInt row, const PetscScalar v[])
492: {
493:   Mat_MPIAIJ  *mat = (Mat_MPIAIJ *)A->data;
494:   Mat_SeqAIJ  *a = (Mat_SeqAIJ *)mat->A->data, *b = (Mat_SeqAIJ *)mat->B->data;
495:   PetscInt     l, *garray                         = mat->garray, diag;
496:   PetscScalar *aa, *ba;

498:   PetscFunctionBegin;
499:   /* code only works for square matrices A */

501:   /* find size of row to the left of the diagonal part */
502:   PetscCall(MatGetOwnershipRange(A, &diag, NULL));
503:   row = row - diag;
504:   for (l = 0; l < b->i[row + 1] - b->i[row]; l++) {
505:     if (garray[b->j[b->i[row] + l]] > diag) break;
506:   }
507:   if (l) {
508:     PetscCall(MatSeqAIJGetArray(mat->B, &ba));
509:     PetscCall(PetscArraycpy(ba + b->i[row], v, l));
510:     PetscCall(MatSeqAIJRestoreArray(mat->B, &ba));
511:   }

513:   /* diagonal part */
514:   if (a->i[row + 1] - a->i[row]) {
515:     PetscCall(MatSeqAIJGetArray(mat->A, &aa));
516:     PetscCall(PetscArraycpy(aa + a->i[row], v + l, a->i[row + 1] - a->i[row]));
517:     PetscCall(MatSeqAIJRestoreArray(mat->A, &aa));
518:   }

520:   /* right of diagonal part */
521:   if (b->i[row + 1] - b->i[row] - l) {
522:     PetscCall(MatSeqAIJGetArray(mat->B, &ba));
523:     PetscCall(PetscArraycpy(ba + b->i[row] + l, v + l + a->i[row + 1] - a->i[row], b->i[row + 1] - b->i[row] - l));
524:     PetscCall(MatSeqAIJRestoreArray(mat->B, &ba));
525:   }
526:   PetscFunctionReturn(PETSC_SUCCESS);
527: }

529: PetscErrorCode MatSetValues_MPIAIJ(Mat mat, PetscInt m, const PetscInt im[], PetscInt n, const PetscInt in[], const PetscScalar v[], InsertMode addv)
530: {
531:   Mat_MPIAIJ *aij   = (Mat_MPIAIJ *)mat->data;
532:   PetscScalar value = 0.0;
533:   PetscInt    i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
534:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
535:   PetscBool   roworiented = aij->roworiented;

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

550:   PetscFunctionBegin;
551:   PetscCall(MatSeqAIJGetArray(A, &aa));
552:   PetscCall(MatSeqAIJGetArray(B, &ba));
553:   for (i = 0; i < m; i++) {
554:     if (im[i] < 0) continue;
555:     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);
556:     if (im[i] >= rstart && im[i] < rend) {
557:       row      = im[i] - rstart;
558:       lastcol1 = -1;
559:       rp1      = PetscSafePointerPlusOffset(aj, ai[row]);
560:       ap1      = PetscSafePointerPlusOffset(aa, ai[row]);
561:       rmax1    = aimax[row];
562:       nrow1    = ailen[row];
563:       low1     = 0;
564:       high1    = nrow1;
565:       lastcol2 = -1;
566:       rp2      = PetscSafePointerPlusOffset(bj, bi[row]);
567:       ap2      = PetscSafePointerPlusOffset(ba, bi[row]);
568:       rmax2    = bimax[row];
569:       nrow2    = bilen[row];
570:       low2     = 0;
571:       high2    = nrow2;

573:       for (j = 0; j < n; j++) {
574:         if (v) value = roworiented ? v[i * n + j] : v[i + j * m];
575:         if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES) && im[i] != in[j]) continue;
576:         if (in[j] >= cstart && in[j] < cend) {
577:           col   = in[j] - cstart;
578:           nonew = a->nonew;
579:           MatSetValues_SeqAIJ_A_Private(row, col, value, addv, im[i], in[j]);
580:         } else if (in[j] < 0) {
581:           continue;
582:         } else {
583:           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);
584:           if (mat->was_assembled) {
585:             if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
586: #if defined(PETSC_USE_CTABLE)
587:             PetscCall(PetscHMapIGetWithDefault(aij->colmap, in[j] + 1, 0, &col)); /* map global col ids to local ones */
588:             col--;
589: #else
590:             col = aij->colmap[in[j]] - 1;
591: #endif
592:             if (col < 0 && !((Mat_SeqAIJ *)aij->B->data)->nonew) { /* col < 0 means in[j] is a new col for B */
593:               PetscCall(MatDisAssemble_MPIAIJ(mat, PETSC_FALSE));  /* Change aij->B from reduced/local format to expanded/global format */
594:               col = in[j];
595:               /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
596:               B     = aij->B;
597:               b     = (Mat_SeqAIJ *)B->data;
598:               bimax = b->imax;
599:               bi    = b->i;
600:               bilen = b->ilen;
601:               bj    = b->j;
602:               ba    = b->a;
603:               rp2   = PetscSafePointerPlusOffset(bj, bi[row]);
604:               ap2   = PetscSafePointerPlusOffset(ba, bi[row]);
605:               rmax2 = bimax[row];
606:               nrow2 = bilen[row];
607:               low2  = 0;
608:               high2 = nrow2;
609:               bm    = aij->B->rmap->n;
610:               ba    = b->a;
611:             } else if (col < 0 && !(ignorezeroentries && value == 0.0)) {
612:               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]);
613:               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]));
614:             }
615:           } else col = in[j];
616:           nonew = b->nonew;
617:           MatSetValues_SeqAIJ_B_Private(row, col, value, addv, im[i], in[j]);
618:         }
619:       }
620:     } else {
621:       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]);
622:       if (!aij->donotstash) {
623:         mat->assembled = PETSC_FALSE;
624:         if (roworiented) {
625:           PetscCall(MatStashValuesRow_Private(&mat->stash, im[i], n, in, PetscSafePointerPlusOffset(v, i * n), (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
626:         } else {
627:           PetscCall(MatStashValuesCol_Private(&mat->stash, im[i], n, in, PetscSafePointerPlusOffset(v, i), m, (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
628:         }
629:       }
630:     }
631:   }
632:   PetscCall(MatSeqAIJRestoreArray(A, &aa)); /* aa, bb might have been free'd due to reallocation above. But we don't access them here */
633:   PetscCall(MatSeqAIJRestoreArray(B, &ba));
634:   PetscFunctionReturn(PETSC_SUCCESS);
635: }

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

656:   PetscFunctionBegin;
657:   /* Iterate over all rows of the matrix */
658:   for (j = 0; j < am; j++) {
659:     dnz = onz = 0;
660:     /*  Iterate over all non-zero columns of the current row */
661:     for (col = mat_i[j]; col < mat_i[j + 1]; col++) {
662:       /* If column is in the diagonal */
663:       if (mat_j[col] >= cstart && mat_j[col] < cend) {
664:         aj[diag_so_far++] = mat_j[col] - cstart;
665:         dnz++;
666:       } else { /* off-diagonal entries */
667:         bj[offd_so_far++] = mat_j[col];
668:         onz++;
669:       }
670:     }
671:     ailen[j] = dnz;
672:     bilen[j] = onz;
673:   }
674:   PetscFunctionReturn(PETSC_SUCCESS);
675: }

677: /*
678:     This function sets the local j, a and ilen arrays (of the diagonal and off-diagonal part) of an MPIAIJ-matrix.
679:     The values in mat_i have to be sorted and the values in mat_j have to be sorted for each row (CSR-like).
680:     No off-processor parts off the matrix are allowed here, they are set at a later point by MatSetValues_MPIAIJ.
681:     Also, mat->was_assembled has to be false, otherwise the statement aj[rowstart_diag+dnz_row] = mat_j[col] - cstart;
682:     would not be true and the more complex MatSetValues_MPIAIJ has to be used.
683: */
684: PetscErrorCode MatSetValues_MPIAIJ_CopyFromCSRFormat(Mat mat, const PetscInt mat_j[], const PetscInt mat_i[], const PetscScalar mat_a[])
685: {
686:   Mat_MPIAIJ  *aij  = (Mat_MPIAIJ *)mat->data;
687:   Mat          A    = aij->A; /* diagonal part of the matrix */
688:   Mat          B    = aij->B; /* off-diagonal part of the matrix */
689:   Mat_SeqAIJ  *aijd = (Mat_SeqAIJ *)aij->A->data, *aijo = (Mat_SeqAIJ *)aij->B->data;
690:   Mat_SeqAIJ  *a      = (Mat_SeqAIJ *)A->data;
691:   Mat_SeqAIJ  *b      = (Mat_SeqAIJ *)B->data;
692:   PetscInt     cstart = mat->cmap->rstart, cend = mat->cmap->rend;
693:   PetscInt    *ailen = a->ilen, *aj = a->j;
694:   PetscInt    *bilen = b->ilen, *bj = b->j;
695:   PetscInt     am          = aij->A->rmap->n, j;
696:   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. */
697:   PetscInt     col, dnz_row, onz_row, rowstart_diag, rowstart_offd;
698:   PetscScalar *aa = a->a, *ba = b->a;

700:   PetscFunctionBegin;
701:   /* Iterate over all rows of the matrix */
702:   for (j = 0; j < am; j++) {
703:     dnz_row = onz_row = 0;
704:     rowstart_offd     = full_offd_i[j];
705:     rowstart_diag     = full_diag_i[j];
706:     /*  Iterate over all non-zero columns of the current row */
707:     for (col = mat_i[j]; col < mat_i[j + 1]; col++) {
708:       /* If column is in the diagonal */
709:       if (mat_j[col] >= cstart && mat_j[col] < cend) {
710:         aj[rowstart_diag + dnz_row] = mat_j[col] - cstart;
711:         aa[rowstart_diag + dnz_row] = mat_a[col];
712:         dnz_row++;
713:       } else { /* off-diagonal entries */
714:         bj[rowstart_offd + onz_row] = mat_j[col];
715:         ba[rowstart_offd + onz_row] = mat_a[col];
716:         onz_row++;
717:       }
718:     }
719:     ailen[j] = dnz_row;
720:     bilen[j] = onz_row;
721:   }
722:   PetscFunctionReturn(PETSC_SUCCESS);
723: }

725: static PetscErrorCode MatGetValues_MPIAIJ(Mat mat, PetscInt m, const PetscInt idxm[], PetscInt n, const PetscInt idxn[], PetscScalar v[])
726: {
727:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
728:   PetscInt    i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
729:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;

731:   PetscFunctionBegin;
732:   for (i = 0; i < m; i++) {
733:     if (idxm[i] < 0) continue; /* negative row */
734:     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);
735:     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);
736:     row = idxm[i] - rstart;
737:     for (j = 0; j < n; j++) {
738:       if (idxn[j] < 0) continue; /* negative column */
739:       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);
740:       if (idxn[j] >= cstart && idxn[j] < cend) {
741:         col = idxn[j] - cstart;
742:         PetscCall(MatGetValues(aij->A, 1, &row, 1, &col, v + i * n + j));
743:       } else {
744:         if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
745: #if defined(PETSC_USE_CTABLE)
746:         PetscCall(PetscHMapIGetWithDefault(aij->colmap, idxn[j] + 1, 0, &col));
747:         col--;
748: #else
749:         col = aij->colmap[idxn[j]] - 1;
750: #endif
751:         if ((col < 0) || (aij->garray[col] != idxn[j])) *(v + i * n + j) = 0.0;
752:         else PetscCall(MatGetValues(aij->B, 1, &row, 1, &col, v + i * n + j));
753:       }
754:     }
755:   }
756:   PetscFunctionReturn(PETSC_SUCCESS);
757: }

759: static PetscErrorCode MatAssemblyBegin_MPIAIJ(Mat mat, MatAssemblyType mode)
760: {
761:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
762:   PetscInt    nstash, reallocs;

764:   PetscFunctionBegin;
765:   if (aij->donotstash || mat->nooffprocentries) PetscFunctionReturn(PETSC_SUCCESS);

767:   PetscCall(MatStashScatterBegin_Private(mat, &mat->stash, mat->rmap->range));
768:   PetscCall(MatStashGetInfo_Private(&mat->stash, &nstash, &reallocs));
769:   PetscCall(PetscInfo(aij->A, "Stash has %" PetscInt_FMT " entries, uses %" PetscInt_FMT " mallocs.\n", nstash, reallocs));
770:   PetscFunctionReturn(PETSC_SUCCESS);
771: }

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

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

784:   PetscFunctionBegin;
785:   if (!aij->donotstash && !mat->nooffprocentries) {
786:     while (1) {
787:       PetscCall(MatStashScatterGetMesg_Private(&mat->stash, &n, &row, &col, &val, &flg));
788:       if (!flg) break;

790:       for (i = 0; i < n;) {
791:         /* Now identify the consecutive vals belonging to the same row */
792:         for (j = i, rstart = row[j]; j < n; j++) {
793:           if (row[j] != rstart) break;
794:         }
795:         if (j < n) ncols = j - i;
796:         else ncols = n - i;
797:         /* Now assemble all these values with a single function call */
798:         PetscCall(MatSetValues_MPIAIJ(mat, 1, row + i, ncols, col + i, val + i, mat->insertmode));
799:         i = j;
800:       }
801:     }
802:     PetscCall(MatStashScatterEnd_Private(&mat->stash));
803:   }
804: #if defined(PETSC_HAVE_DEVICE)
805:   if (mat->offloadmask == PETSC_OFFLOAD_CPU) aij->A->offloadmask = PETSC_OFFLOAD_CPU;
806:   /* We call MatBindToCPU() on aij->A and aij->B here, because if MatBindToCPU_MPIAIJ() is called before assembly, it cannot bind these. */
807:   if (mat->boundtocpu) {
808:     PetscCall(MatBindToCPU(aij->A, PETSC_TRUE));
809:     PetscCall(MatBindToCPU(aij->B, PETSC_TRUE));
810:   }
811: #endif
812:   PetscCall(MatAssemblyBegin(aij->A, mode));
813:   PetscCall(MatAssemblyEnd(aij->A, mode));

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

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

837:   aij->rowvalues = NULL;

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

841:   /* if no new nonzero locations are allowed in matrix then only set the matrix state the first time through */
842:   if ((!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) || !((Mat_SeqAIJ *)aij->A->data)->nonew) {
843:     PetscObjectState state = aij->A->nonzerostate + aij->B->nonzerostate;
844:     PetscCallMPI(MPIU_Allreduce(&state, &mat->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)mat)));
845:   }
846: #if defined(PETSC_HAVE_DEVICE)
847:   mat->offloadmask = PETSC_OFFLOAD_BOTH;
848: #endif
849:   PetscFunctionReturn(PETSC_SUCCESS);
850: }

852: static PetscErrorCode MatZeroEntries_MPIAIJ(Mat A)
853: {
854:   Mat_MPIAIJ *l = (Mat_MPIAIJ *)A->data;

856:   PetscFunctionBegin;
857:   PetscCall(MatZeroEntries(l->A));
858:   PetscCall(MatZeroEntries(l->B));
859:   PetscFunctionReturn(PETSC_SUCCESS);
860: }

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

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

878:     PetscCheck(cong, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Need matching row/col layout");
879:     PetscCall(VecGetArrayRead(x, &xx));
880:     PetscCall(VecGetArray(b, &bb));
881:     for (r = 0; r < len; ++r) bb[lrows[r]] = diag * xx[lrows[r]];
882:     PetscCall(VecRestoreArrayRead(x, &xx));
883:     PetscCall(VecRestoreArray(b, &bb));
884:   }

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

895:     nnwA = aijA->nonew;
896:     nnwB = aijB->nonew;
897:     nnzA = aijA->keepnonzeropattern;
898:     nnzB = aijB->keepnonzeropattern;
899:     if (!nnzA) {
900:       PetscCall(PetscInfo(mat->A, "Requested to not keep the pattern and add a nonzero diagonal; may encounter reallocations on diagonal block.\n"));
901:       aijA->nonew = 0;
902:     }
903:     if (!nnzB) {
904:       PetscCall(PetscInfo(mat->B, "Requested to not keep the pattern and add a nonzero diagonal; may encounter reallocations on off-diagonal block.\n"));
905:       aijB->nonew = 0;
906:     }
907:     /* Must zero here before the next loop */
908:     PetscCall(MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL));
909:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
910:     for (r = 0; r < len; ++r) {
911:       const PetscInt row = lrows[r] + A->rmap->rstart;
912:       if (row >= A->cmap->N) continue;
913:       PetscCall(MatSetValues(A, 1, &row, 1, &row, &diag, INSERT_VALUES));
914:     }
915:     aijA->nonew = nnwA;
916:     aijB->nonew = nnwB;
917:   } else {
918:     PetscCall(MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL));
919:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
920:   }
921:   PetscCall(PetscFree(lrows));
922:   PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
923:   PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));

925:   /* only change matrix nonzero state if pattern was allowed to be changed */
926:   if (!((Mat_SeqAIJ *)mat->A->data)->keepnonzeropattern || !((Mat_SeqAIJ *)mat->A->data)->nonew) {
927:     PetscObjectState state = mat->A->nonzerostate + mat->B->nonzerostate;
928:     PetscCallMPI(MPIU_Allreduce(&state, &A->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)A)));
929:   }
930:   PetscFunctionReturn(PETSC_SUCCESS);
931: }

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

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

986:     PetscCall(MatHasCongruentLayouts(A, &cong));
987:     PetscCheck(cong, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Need matching row/col layout");
988:     PetscCall(VecScatterBegin(l->Mvctx, x, l->lvec, INSERT_VALUES, SCATTER_FORWARD));
989:     PetscCall(VecScatterEnd(l->Mvctx, x, l->lvec, INSERT_VALUES, SCATTER_FORWARD));
990:     PetscCall(VecGetArrayRead(l->lvec, &xx));
991:     PetscCall(VecGetArray(b, &bb));
992:   }
993:   PetscCall(VecGetArray(lmask, &mask));
994:   /* remove zeroed rows of off-diagonal matrix */
995:   PetscCall(MatSeqAIJGetArray(l->B, &aij_a));
996:   ii = aij->i;
997:   for (i = 0; i < len; i++) PetscCall(PetscArrayzero(PetscSafePointerPlusOffset(aij_a, ii[lrows[i]]), ii[lrows[i] + 1] - ii[lrows[i]]));
998:   /* loop over all elements of off process part of matrix zeroing removed columns*/
999:   if (aij->compressedrow.use) {
1000:     m    = aij->compressedrow.nrows;
1001:     ii   = aij->compressedrow.i;
1002:     ridx = aij->compressedrow.rindex;
1003:     for (i = 0; i < m; i++) {
1004:       n  = ii[i + 1] - ii[i];
1005:       aj = aij->j + ii[i];
1006:       aa = aij_a + ii[i];

1008:       for (j = 0; j < n; j++) {
1009:         if (PetscAbsScalar(mask[*aj])) {
1010:           if (b) bb[*ridx] -= *aa * xx[*aj];
1011:           *aa = 0.0;
1012:         }
1013:         aa++;
1014:         aj++;
1015:       }
1016:       ridx++;
1017:     }
1018:   } else { /* do not use compressed row format */
1019:     m = l->B->rmap->n;
1020:     for (i = 0; i < m; i++) {
1021:       n  = ii[i + 1] - ii[i];
1022:       aj = aij->j + ii[i];
1023:       aa = aij_a + ii[i];
1024:       for (j = 0; j < n; j++) {
1025:         if (PetscAbsScalar(mask[*aj])) {
1026:           if (b) bb[i] -= *aa * xx[*aj];
1027:           *aa = 0.0;
1028:         }
1029:         aa++;
1030:         aj++;
1031:       }
1032:     }
1033:   }
1034:   if (x && b) {
1035:     PetscCall(VecRestoreArray(b, &bb));
1036:     PetscCall(VecRestoreArrayRead(l->lvec, &xx));
1037:   }
1038:   PetscCall(MatSeqAIJRestoreArray(l->B, &aij_a));
1039:   PetscCall(VecRestoreArray(lmask, &mask));
1040:   PetscCall(VecDestroy(&lmask));
1041:   PetscCall(PetscFree(lrows));

1043:   /* only change matrix nonzero state if pattern was allowed to be changed */
1044:   if (!((Mat_SeqAIJ *)l->A->data)->nonew) {
1045:     PetscObjectState state = l->A->nonzerostate + l->B->nonzerostate;
1046:     PetscCallMPI(MPIU_Allreduce(&state, &A->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)A)));
1047:   }
1048:   PetscFunctionReturn(PETSC_SUCCESS);
1049: }

1051: static PetscErrorCode MatMult_MPIAIJ(Mat A, Vec xx, Vec yy)
1052: {
1053:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
1054:   PetscInt    nt;
1055:   VecScatter  Mvctx = a->Mvctx;

1057:   PetscFunctionBegin;
1058:   PetscCall(VecGetLocalSize(xx, &nt));
1059:   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);
1060:   PetscCall(VecScatterBegin(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1061:   PetscUseTypeMethod(a->A, mult, xx, yy);
1062:   PetscCall(VecScatterEnd(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1063:   PetscUseTypeMethod(a->B, multadd, a->lvec, yy, yy);
1064:   PetscFunctionReturn(PETSC_SUCCESS);
1065: }

1067: static PetscErrorCode MatMultDiagonalBlock_MPIAIJ(Mat A, Vec bb, Vec xx)
1068: {
1069:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1071:   PetscFunctionBegin;
1072:   PetscCall(MatMultDiagonalBlock(a->A, bb, xx));
1073:   PetscFunctionReturn(PETSC_SUCCESS);
1074: }

1076: static PetscErrorCode MatMultAdd_MPIAIJ(Mat A, Vec xx, Vec yy, Vec zz)
1077: {
1078:   Mat_MPIAIJ *a     = (Mat_MPIAIJ *)A->data;
1079:   VecScatter  Mvctx = a->Mvctx;

1081:   PetscFunctionBegin;
1082:   PetscCall(VecScatterBegin(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1083:   PetscCall((*a->A->ops->multadd)(a->A, xx, yy, zz));
1084:   PetscCall(VecScatterEnd(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1085:   PetscCall((*a->B->ops->multadd)(a->B, a->lvec, zz, zz));
1086:   PetscFunctionReturn(PETSC_SUCCESS);
1087: }

1089: static PetscErrorCode MatMultTranspose_MPIAIJ(Mat A, Vec xx, Vec yy)
1090: {
1091:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1093:   PetscFunctionBegin;
1094:   /* do nondiagonal part */
1095:   PetscCall((*a->B->ops->multtranspose)(a->B, xx, a->lvec));
1096:   /* do local part */
1097:   PetscCall((*a->A->ops->multtranspose)(a->A, xx, yy));
1098:   /* add partial results together */
1099:   PetscCall(VecScatterBegin(a->Mvctx, a->lvec, yy, ADD_VALUES, SCATTER_REVERSE));
1100:   PetscCall(VecScatterEnd(a->Mvctx, a->lvec, yy, ADD_VALUES, SCATTER_REVERSE));
1101:   PetscFunctionReturn(PETSC_SUCCESS);
1102: }

1104: static PetscErrorCode MatIsTranspose_MPIAIJ(Mat Amat, Mat Bmat, PetscReal tol, PetscBool *f)
1105: {
1106:   MPI_Comm    comm;
1107:   Mat_MPIAIJ *Aij = (Mat_MPIAIJ *)Amat->data, *Bij = (Mat_MPIAIJ *)Bmat->data;
1108:   Mat         Adia = Aij->A, Bdia = Bij->A, Aoff, Boff, *Aoffs, *Boffs;
1109:   IS          Me, Notme;
1110:   PetscInt    M, N, first, last, *notme, i;
1111:   PetscBool   lf;
1112:   PetscMPIInt size;

1114:   PetscFunctionBegin;
1115:   /* Easy test: symmetric diagonal block */
1116:   PetscCall(MatIsTranspose(Adia, Bdia, tol, &lf));
1117:   PetscCallMPI(MPIU_Allreduce(&lf, f, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)Amat)));
1118:   if (!*f) PetscFunctionReturn(PETSC_SUCCESS);
1119:   PetscCall(PetscObjectGetComm((PetscObject)Amat, &comm));
1120:   PetscCallMPI(MPI_Comm_size(comm, &size));
1121:   if (size == 1) PetscFunctionReturn(PETSC_SUCCESS);

1123:   /* Hard test: off-diagonal block. This takes a MatCreateSubMatrix. */
1124:   PetscCall(MatGetSize(Amat, &M, &N));
1125:   PetscCall(MatGetOwnershipRange(Amat, &first, &last));
1126:   PetscCall(PetscMalloc1(N - last + first, &notme));
1127:   for (i = 0; i < first; i++) notme[i] = i;
1128:   for (i = last; i < M; i++) notme[i - last + first] = i;
1129:   PetscCall(ISCreateGeneral(MPI_COMM_SELF, N - last + first, notme, PETSC_COPY_VALUES, &Notme));
1130:   PetscCall(ISCreateStride(MPI_COMM_SELF, last - first, first, 1, &Me));
1131:   PetscCall(MatCreateSubMatrices(Amat, 1, &Me, &Notme, MAT_INITIAL_MATRIX, &Aoffs));
1132:   Aoff = Aoffs[0];
1133:   PetscCall(MatCreateSubMatrices(Bmat, 1, &Notme, &Me, MAT_INITIAL_MATRIX, &Boffs));
1134:   Boff = Boffs[0];
1135:   PetscCall(MatIsTranspose(Aoff, Boff, tol, f));
1136:   PetscCall(MatDestroyMatrices(1, &Aoffs));
1137:   PetscCall(MatDestroyMatrices(1, &Boffs));
1138:   PetscCall(ISDestroy(&Me));
1139:   PetscCall(ISDestroy(&Notme));
1140:   PetscCall(PetscFree(notme));
1141:   PetscFunctionReturn(PETSC_SUCCESS);
1142: }

1144: static PetscErrorCode MatMultTransposeAdd_MPIAIJ(Mat A, Vec xx, Vec yy, Vec zz)
1145: {
1146:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1148:   PetscFunctionBegin;
1149:   /* do nondiagonal part */
1150:   PetscCall((*a->B->ops->multtranspose)(a->B, xx, a->lvec));
1151:   /* do local part */
1152:   PetscCall((*a->A->ops->multtransposeadd)(a->A, xx, yy, zz));
1153:   /* add partial results together */
1154:   PetscCall(VecScatterBegin(a->Mvctx, a->lvec, zz, ADD_VALUES, SCATTER_REVERSE));
1155:   PetscCall(VecScatterEnd(a->Mvctx, a->lvec, zz, ADD_VALUES, SCATTER_REVERSE));
1156:   PetscFunctionReturn(PETSC_SUCCESS);
1157: }

1159: /*
1160:   This only works correctly for square matrices where the subblock A->A is the
1161:    diagonal block
1162: */
1163: static PetscErrorCode MatGetDiagonal_MPIAIJ(Mat A, Vec v)
1164: {
1165:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1167:   PetscFunctionBegin;
1168:   PetscCheck(A->rmap->N == A->cmap->N, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Supports only square matrix where A->A is diag block");
1169:   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");
1170:   PetscCall(MatGetDiagonal(a->A, v));
1171:   PetscFunctionReturn(PETSC_SUCCESS);
1172: }

1174: static PetscErrorCode MatScale_MPIAIJ(Mat A, PetscScalar aa)
1175: {
1176:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1178:   PetscFunctionBegin;
1179:   PetscCall(MatScale(a->A, aa));
1180:   PetscCall(MatScale(a->B, aa));
1181:   PetscFunctionReturn(PETSC_SUCCESS);
1182: }

1184: static PetscErrorCode MatView_MPIAIJ_Binary(Mat mat, PetscViewer viewer)
1185: {
1186:   Mat_MPIAIJ        *aij    = (Mat_MPIAIJ *)mat->data;
1187:   Mat_SeqAIJ        *A      = (Mat_SeqAIJ *)aij->A->data;
1188:   Mat_SeqAIJ        *B      = (Mat_SeqAIJ *)aij->B->data;
1189:   const PetscInt    *garray = aij->garray;
1190:   const PetscScalar *aa, *ba;
1191:   PetscInt           header[4], M, N, m, rs, cs, cnt, i, ja, jb;
1192:   PetscInt64         nz, hnz;
1193:   PetscInt          *rowlens;
1194:   PetscInt          *colidxs;
1195:   PetscScalar       *matvals;
1196:   PetscMPIInt        rank;

1198:   PetscFunctionBegin;
1199:   PetscCall(PetscViewerSetUp(viewer));

1201:   M  = mat->rmap->N;
1202:   N  = mat->cmap->N;
1203:   m  = mat->rmap->n;
1204:   rs = mat->rmap->rstart;
1205:   cs = mat->cmap->rstart;
1206:   nz = A->nz + B->nz;

1208:   /* write matrix header */
1209:   header[0] = MAT_FILE_CLASSID;
1210:   header[1] = M;
1211:   header[2] = N;
1212:   PetscCallMPI(MPI_Reduce(&nz, &hnz, 1, MPIU_INT64, MPI_SUM, 0, PetscObjectComm((PetscObject)mat)));
1213:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)mat), &rank));
1214:   if (rank == 0) PetscCall(PetscIntCast(hnz, &header[3]));
1215:   PetscCall(PetscViewerBinaryWrite(viewer, header, 4, PETSC_INT));

1217:   /* fill in and store row lengths  */
1218:   PetscCall(PetscMalloc1(m, &rowlens));
1219:   for (i = 0; i < m; i++) rowlens[i] = A->i[i + 1] - A->i[i] + B->i[i + 1] - B->i[i];
1220:   PetscCall(PetscViewerBinaryWriteAll(viewer, rowlens, m, rs, M, PETSC_INT));
1221:   PetscCall(PetscFree(rowlens));

1223:   /* fill in and store column indices */
1224:   PetscCall(PetscMalloc1(nz, &colidxs));
1225:   for (cnt = 0, i = 0; i < m; i++) {
1226:     for (jb = B->i[i]; jb < B->i[i + 1]; jb++) {
1227:       if (garray[B->j[jb]] > cs) break;
1228:       colidxs[cnt++] = garray[B->j[jb]];
1229:     }
1230:     for (ja = A->i[i]; ja < A->i[i + 1]; ja++) colidxs[cnt++] = A->j[ja] + cs;
1231:     for (; jb < B->i[i + 1]; jb++) colidxs[cnt++] = garray[B->j[jb]];
1232:   }
1233:   PetscCheck(cnt == nz, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Internal PETSc error: cnt = %" PetscInt_FMT " nz = %" PetscInt64_FMT, cnt, nz);
1234:   PetscCall(PetscViewerBinaryWriteAll(viewer, colidxs, nz, PETSC_DETERMINE, PETSC_DETERMINE, PETSC_INT));
1235:   PetscCall(PetscFree(colidxs));

1237:   /* fill in and store nonzero values */
1238:   PetscCall(MatSeqAIJGetArrayRead(aij->A, &aa));
1239:   PetscCall(MatSeqAIJGetArrayRead(aij->B, &ba));
1240:   PetscCall(PetscMalloc1(nz, &matvals));
1241:   for (cnt = 0, i = 0; i < m; i++) {
1242:     for (jb = B->i[i]; jb < B->i[i + 1]; jb++) {
1243:       if (garray[B->j[jb]] > cs) break;
1244:       matvals[cnt++] = ba[jb];
1245:     }
1246:     for (ja = A->i[i]; ja < A->i[i + 1]; ja++) matvals[cnt++] = aa[ja];
1247:     for (; jb < B->i[i + 1]; jb++) matvals[cnt++] = ba[jb];
1248:   }
1249:   PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &aa));
1250:   PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &ba));
1251:   PetscCheck(cnt == nz, PETSC_COMM_SELF, PETSC_ERR_LIB, "Internal PETSc error: cnt = %" PetscInt_FMT " nz = %" PetscInt64_FMT, cnt, nz);
1252:   PetscCall(PetscViewerBinaryWriteAll(viewer, matvals, nz, PETSC_DETERMINE, PETSC_DETERMINE, PETSC_SCALAR));
1253:   PetscCall(PetscFree(matvals));

1255:   /* write block size option to the viewer's .info file */
1256:   PetscCall(MatView_Binary_BlockSizes(mat, viewer));
1257:   PetscFunctionReturn(PETSC_SUCCESS);
1258: }

1260: #include <petscdraw.h>
1261: static PetscErrorCode MatView_MPIAIJ_ASCIIorDraworSocket(Mat mat, PetscViewer viewer)
1262: {
1263:   Mat_MPIAIJ       *aij  = (Mat_MPIAIJ *)mat->data;
1264:   PetscMPIInt       rank = aij->rank, size = aij->size;
1265:   PetscBool         isdraw, isascii, isbinary;
1266:   PetscViewer       sviewer;
1267:   PetscViewerFormat format;

1269:   PetscFunctionBegin;
1270:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERDRAW, &isdraw));
1271:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &isascii));
1272:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
1273:   if (isascii) {
1274:     PetscCall(PetscViewerGetFormat(viewer, &format));
1275:     if (format == PETSC_VIEWER_LOAD_BALANCE) {
1276:       PetscInt i, nmax = 0, nmin = PETSC_INT_MAX, navg = 0, *nz, nzlocal = ((Mat_SeqAIJ *)aij->A->data)->nz + ((Mat_SeqAIJ *)aij->B->data)->nz;
1277:       PetscCall(PetscMalloc1(size, &nz));
1278:       PetscCallMPI(MPI_Allgather(&nzlocal, 1, MPIU_INT, nz, 1, MPIU_INT, PetscObjectComm((PetscObject)mat)));
1279:       for (i = 0; i < size; i++) {
1280:         nmax = PetscMax(nmax, nz[i]);
1281:         nmin = PetscMin(nmin, nz[i]);
1282:         navg += nz[i];
1283:       }
1284:       PetscCall(PetscFree(nz));
1285:       navg = navg / size;
1286:       PetscCall(PetscViewerASCIIPrintf(viewer, "Load Balance - Nonzeros: Min %" PetscInt_FMT "  avg %" PetscInt_FMT "  max %" PetscInt_FMT "\n", nmin, navg, nmax));
1287:       PetscFunctionReturn(PETSC_SUCCESS);
1288:     }
1289:     PetscCall(PetscViewerGetFormat(viewer, &format));
1290:     if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
1291:       MatInfo   info;
1292:       PetscInt *inodes = NULL;

1294:       PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)mat), &rank));
1295:       PetscCall(MatGetInfo(mat, MAT_LOCAL, &info));
1296:       PetscCall(MatInodeGetInodeSizes(aij->A, NULL, &inodes, NULL));
1297:       PetscCall(PetscViewerASCIIPushSynchronized(viewer));
1298:       if (!inodes) {
1299:         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,
1300:                                                      info.memory));
1301:       } else {
1302:         PetscCall(
1303:           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));
1304:       }
1305:       PetscCall(MatGetInfo(aij->A, MAT_LOCAL, &info));
1306:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] on-diagonal part: nz %" PetscInt_FMT " \n", rank, (PetscInt)info.nz_used));
1307:       PetscCall(MatGetInfo(aij->B, MAT_LOCAL, &info));
1308:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] off-diagonal part: nz %" PetscInt_FMT " \n", rank, (PetscInt)info.nz_used));
1309:       PetscCall(PetscViewerFlush(viewer));
1310:       PetscCall(PetscViewerASCIIPopSynchronized(viewer));
1311:       PetscCall(PetscViewerASCIIPrintf(viewer, "Information on VecScatter used in matrix-vector product: \n"));
1312:       PetscCall(VecScatterView(aij->Mvctx, viewer));
1313:       PetscFunctionReturn(PETSC_SUCCESS);
1314:     } else if (format == PETSC_VIEWER_ASCII_INFO) {
1315:       PetscInt inodecount, inodelimit, *inodes;
1316:       PetscCall(MatInodeGetInodeSizes(aij->A, &inodecount, &inodes, &inodelimit));
1317:       if (inodes) {
1318:         PetscCall(PetscViewerASCIIPrintf(viewer, "using I-node (on process 0) routines: found %" PetscInt_FMT " nodes, limit used is %" PetscInt_FMT "\n", inodecount, inodelimit));
1319:       } else {
1320:         PetscCall(PetscViewerASCIIPrintf(viewer, "not using I-node (on process 0) routines\n"));
1321:       }
1322:       PetscFunctionReturn(PETSC_SUCCESS);
1323:     } else if (format == PETSC_VIEWER_ASCII_FACTOR_INFO) {
1324:       PetscFunctionReturn(PETSC_SUCCESS);
1325:     }
1326:   } else if (isbinary) {
1327:     if (size == 1) {
1328:       PetscCall(PetscObjectSetName((PetscObject)aij->A, ((PetscObject)mat)->name));
1329:       PetscCall(MatView(aij->A, viewer));
1330:     } else {
1331:       PetscCall(MatView_MPIAIJ_Binary(mat, viewer));
1332:     }
1333:     PetscFunctionReturn(PETSC_SUCCESS);
1334:   } else if (isascii && size == 1) {
1335:     PetscCall(PetscObjectSetName((PetscObject)aij->A, ((PetscObject)mat)->name));
1336:     PetscCall(MatView(aij->A, viewer));
1337:     PetscFunctionReturn(PETSC_SUCCESS);
1338:   } else if (isdraw) {
1339:     PetscDraw draw;
1340:     PetscBool isnull;
1341:     PetscCall(PetscViewerDrawGetDraw(viewer, 0, &draw));
1342:     PetscCall(PetscDrawIsNull(draw, &isnull));
1343:     if (isnull) PetscFunctionReturn(PETSC_SUCCESS);
1344:   }

1346:   { /* assemble the entire matrix onto first processor */
1347:     Mat A = NULL, Av;
1348:     IS  isrow, iscol;

1350:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat), rank == 0 ? mat->rmap->N : 0, 0, 1, &isrow));
1351:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat), rank == 0 ? mat->cmap->N : 0, 0, 1, &iscol));
1352:     PetscCall(MatCreateSubMatrix(mat, isrow, iscol, MAT_INITIAL_MATRIX, &A));
1353:     PetscCall(MatMPIAIJGetSeqAIJ(A, &Av, NULL, NULL));
1354:     /*  The commented code uses MatCreateSubMatrices instead */
1355:     /*
1356:     Mat *AA, A = NULL, Av;
1357:     IS  isrow,iscol;

1359:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat),rank == 0 ? mat->rmap->N : 0,0,1,&isrow));
1360:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat),rank == 0 ? mat->cmap->N : 0,0,1,&iscol));
1361:     PetscCall(MatCreateSubMatrices(mat,1,&isrow,&iscol,MAT_INITIAL_MATRIX,&AA));
1362:     if (rank == 0) {
1363:        PetscCall(PetscObjectReference((PetscObject)AA[0]));
1364:        A    = AA[0];
1365:        Av   = AA[0];
1366:     }
1367:     PetscCall(MatDestroySubMatrices(1,&AA));
1368: */
1369:     PetscCall(ISDestroy(&iscol));
1370:     PetscCall(ISDestroy(&isrow));
1371:     /*
1372:        Everyone has to call to draw the matrix since the graphics waits are
1373:        synchronized across all processors that share the PetscDraw object
1374:     */
1375:     PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
1376:     if (rank == 0) {
1377:       if (((PetscObject)mat)->name) PetscCall(PetscObjectSetName((PetscObject)Av, ((PetscObject)mat)->name));
1378:       PetscCall(MatView_SeqAIJ(Av, sviewer));
1379:     }
1380:     PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
1381:     PetscCall(MatDestroy(&A));
1382:   }
1383:   PetscFunctionReturn(PETSC_SUCCESS);
1384: }

1386: PetscErrorCode MatView_MPIAIJ(Mat mat, PetscViewer viewer)
1387: {
1388:   PetscBool isascii, isdraw, issocket, isbinary;

1390:   PetscFunctionBegin;
1391:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &isascii));
1392:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERDRAW, &isdraw));
1393:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
1394:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERSOCKET, &issocket));
1395:   if (isascii || isdraw || isbinary || issocket) PetscCall(MatView_MPIAIJ_ASCIIorDraworSocket(mat, viewer));
1396:   PetscFunctionReturn(PETSC_SUCCESS);
1397: }

1399: static PetscErrorCode MatSOR_MPIAIJ(Mat matin, Vec bb, PetscReal omega, MatSORType flag, PetscReal fshift, PetscInt its, PetscInt lits, Vec xx)
1400: {
1401:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)matin->data;
1402:   Vec         bb1 = NULL;
1403:   PetscBool   hasop;

1405:   PetscFunctionBegin;
1406:   if (flag == SOR_APPLY_UPPER) {
1407:     PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, flag, fshift, lits, 1, xx));
1408:     PetscFunctionReturn(PETSC_SUCCESS);
1409:   }

1411:   if (its > 1 || ~flag & SOR_ZERO_INITIAL_GUESS || flag & SOR_EISENSTAT) PetscCall(VecDuplicate(bb, &bb1));

1413:   if ((flag & SOR_LOCAL_SYMMETRIC_SWEEP) == SOR_LOCAL_SYMMETRIC_SWEEP) {
1414:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1415:       PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, flag, fshift, lits, 1, xx));
1416:       its--;
1417:     }

1419:     while (its--) {
1420:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1421:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1423:       /* update rhs: bb1 = bb - B*x */
1424:       PetscCall(VecScale(mat->lvec, -1.0));
1425:       PetscCall((*mat->B->ops->multadd)(mat->B, mat->lvec, bb, bb1));

1427:       /* local sweep */
1428:       PetscCall((*mat->A->ops->sor)(mat->A, bb1, omega, SOR_SYMMETRIC_SWEEP, fshift, lits, 1, xx));
1429:     }
1430:   } else if (flag & SOR_LOCAL_FORWARD_SWEEP) {
1431:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1432:       PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, flag, fshift, lits, 1, xx));
1433:       its--;
1434:     }
1435:     while (its--) {
1436:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1437:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1439:       /* update rhs: bb1 = bb - B*x */
1440:       PetscCall(VecScale(mat->lvec, -1.0));
1441:       PetscCall((*mat->B->ops->multadd)(mat->B, mat->lvec, bb, bb1));

1443:       /* local sweep */
1444:       PetscCall((*mat->A->ops->sor)(mat->A, bb1, omega, SOR_FORWARD_SWEEP, fshift, lits, 1, xx));
1445:     }
1446:   } else if (flag & SOR_LOCAL_BACKWARD_SWEEP) {
1447:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1448:       PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, flag, fshift, lits, 1, xx));
1449:       its--;
1450:     }
1451:     while (its--) {
1452:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1453:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1455:       /* update rhs: bb1 = bb - B*x */
1456:       PetscCall(VecScale(mat->lvec, -1.0));
1457:       PetscCall((*mat->B->ops->multadd)(mat->B, mat->lvec, bb, bb1));

1459:       /* local sweep */
1460:       PetscCall((*mat->A->ops->sor)(mat->A, bb1, omega, SOR_BACKWARD_SWEEP, fshift, lits, 1, xx));
1461:     }
1462:   } else if (flag & SOR_EISENSTAT) {
1463:     Vec xx1;

1465:     PetscCall(VecDuplicate(bb, &xx1));
1466:     PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, (MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_BACKWARD_SWEEP), fshift, lits, 1, xx));

1468:     PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1469:     PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1470:     if (!mat->diag) {
1471:       PetscCall(MatCreateVecs(matin, &mat->diag, NULL));
1472:       PetscCall(MatGetDiagonal(matin, mat->diag));
1473:     }
1474:     PetscCall(MatHasOperation(matin, MATOP_MULT_DIAGONAL_BLOCK, &hasop));
1475:     if (hasop) {
1476:       PetscCall(MatMultDiagonalBlock(matin, xx, bb1));
1477:     } else {
1478:       PetscCall(VecPointwiseMult(bb1, mat->diag, xx));
1479:     }
1480:     PetscCall(VecAYPX(bb1, (omega - 2.0) / omega, bb));

1482:     PetscCall(MatMultAdd(mat->B, mat->lvec, bb1, bb1));

1484:     /* local sweep */
1485:     PetscCall((*mat->A->ops->sor)(mat->A, bb1, omega, (MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_FORWARD_SWEEP), fshift, lits, 1, xx1));
1486:     PetscCall(VecAXPY(xx, 1.0, xx1));
1487:     PetscCall(VecDestroy(&xx1));
1488:   } else SETERRQ(PetscObjectComm((PetscObject)matin), PETSC_ERR_SUP, "Parallel SOR not supported");

1490:   PetscCall(VecDestroy(&bb1));

1492:   matin->factorerrortype = mat->A->factorerrortype;
1493:   PetscFunctionReturn(PETSC_SUCCESS);
1494: }

1496: static PetscErrorCode MatPermute_MPIAIJ(Mat A, IS rowp, IS colp, Mat *B)
1497: {
1498:   Mat             aA, aB, Aperm;
1499:   const PetscInt *rwant, *cwant, *gcols, *ai, *bi, *aj, *bj;
1500:   PetscScalar    *aa, *ba;
1501:   PetscInt        i, j, m, n, ng, anz, bnz, *dnnz, *onnz, *tdnnz, *tonnz, *rdest, *cdest, *work, *gcdest;
1502:   PetscSF         rowsf, sf;
1503:   IS              parcolp = NULL;
1504:   PetscBool       done;

1506:   PetscFunctionBegin;
1507:   PetscCall(MatGetLocalSize(A, &m, &n));
1508:   PetscCall(ISGetIndices(rowp, &rwant));
1509:   PetscCall(ISGetIndices(colp, &cwant));
1510:   PetscCall(PetscMalloc3(PetscMax(m, n), &work, m, &rdest, n, &cdest));

1512:   /* Invert row permutation to find out where my rows should go */
1513:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &rowsf));
1514:   PetscCall(PetscSFSetGraphLayout(rowsf, A->rmap, A->rmap->n, NULL, PETSC_OWN_POINTER, rwant));
1515:   PetscCall(PetscSFSetFromOptions(rowsf));
1516:   for (i = 0; i < m; i++) work[i] = A->rmap->rstart + i;
1517:   PetscCall(PetscSFReduceBegin(rowsf, MPIU_INT, work, rdest, MPI_REPLACE));
1518:   PetscCall(PetscSFReduceEnd(rowsf, MPIU_INT, work, rdest, MPI_REPLACE));

1520:   /* Invert column permutation to find out where my columns should go */
1521:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1522:   PetscCall(PetscSFSetGraphLayout(sf, A->cmap, A->cmap->n, NULL, PETSC_OWN_POINTER, cwant));
1523:   PetscCall(PetscSFSetFromOptions(sf));
1524:   for (i = 0; i < n; i++) work[i] = A->cmap->rstart + i;
1525:   PetscCall(PetscSFReduceBegin(sf, MPIU_INT, work, cdest, MPI_REPLACE));
1526:   PetscCall(PetscSFReduceEnd(sf, MPIU_INT, work, cdest, MPI_REPLACE));
1527:   PetscCall(PetscSFDestroy(&sf));

1529:   PetscCall(ISRestoreIndices(rowp, &rwant));
1530:   PetscCall(ISRestoreIndices(colp, &cwant));
1531:   PetscCall(MatMPIAIJGetSeqAIJ(A, &aA, &aB, &gcols));

1533:   /* Find out where my gcols should go */
1534:   PetscCall(MatGetSize(aB, NULL, &ng));
1535:   PetscCall(PetscMalloc1(ng, &gcdest));
1536:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1537:   PetscCall(PetscSFSetGraphLayout(sf, A->cmap, ng, NULL, PETSC_OWN_POINTER, gcols));
1538:   PetscCall(PetscSFSetFromOptions(sf));
1539:   PetscCall(PetscSFBcastBegin(sf, MPIU_INT, cdest, gcdest, MPI_REPLACE));
1540:   PetscCall(PetscSFBcastEnd(sf, MPIU_INT, cdest, gcdest, MPI_REPLACE));
1541:   PetscCall(PetscSFDestroy(&sf));

1543:   PetscCall(PetscCalloc4(m, &dnnz, m, &onnz, m, &tdnnz, m, &tonnz));
1544:   PetscCall(MatGetRowIJ(aA, 0, PETSC_FALSE, PETSC_FALSE, &anz, &ai, &aj, &done));
1545:   PetscCall(MatGetRowIJ(aB, 0, PETSC_FALSE, PETSC_FALSE, &bnz, &bi, &bj, &done));
1546:   for (i = 0; i < m; i++) {
1547:     PetscInt    row = rdest[i];
1548:     PetscMPIInt rowner;
1549:     PetscCall(PetscLayoutFindOwner(A->rmap, row, &rowner));
1550:     for (j = ai[i]; j < ai[i + 1]; j++) {
1551:       PetscInt    col = cdest[aj[j]];
1552:       PetscMPIInt cowner;
1553:       PetscCall(PetscLayoutFindOwner(A->cmap, col, &cowner)); /* Could build an index for the columns to eliminate this search */
1554:       if (rowner == cowner) dnnz[i]++;
1555:       else onnz[i]++;
1556:     }
1557:     for (j = bi[i]; j < bi[i + 1]; j++) {
1558:       PetscInt    col = gcdest[bj[j]];
1559:       PetscMPIInt cowner;
1560:       PetscCall(PetscLayoutFindOwner(A->cmap, col, &cowner));
1561:       if (rowner == cowner) dnnz[i]++;
1562:       else onnz[i]++;
1563:     }
1564:   }
1565:   PetscCall(PetscSFBcastBegin(rowsf, MPIU_INT, dnnz, tdnnz, MPI_REPLACE));
1566:   PetscCall(PetscSFBcastEnd(rowsf, MPIU_INT, dnnz, tdnnz, MPI_REPLACE));
1567:   PetscCall(PetscSFBcastBegin(rowsf, MPIU_INT, onnz, tonnz, MPI_REPLACE));
1568:   PetscCall(PetscSFBcastEnd(rowsf, MPIU_INT, onnz, tonnz, MPI_REPLACE));
1569:   PetscCall(PetscSFDestroy(&rowsf));

1571:   PetscCall(MatCreateAIJ(PetscObjectComm((PetscObject)A), A->rmap->n, A->cmap->n, A->rmap->N, A->cmap->N, 0, tdnnz, 0, tonnz, &Aperm));
1572:   PetscCall(MatSeqAIJGetArray(aA, &aa));
1573:   PetscCall(MatSeqAIJGetArray(aB, &ba));
1574:   for (i = 0; i < m; i++) {
1575:     PetscInt *acols = dnnz, *bcols = onnz; /* Repurpose now-unneeded arrays */
1576:     PetscInt  j0, rowlen;
1577:     rowlen = ai[i + 1] - ai[i];
1578:     for (j0 = j = 0; j < rowlen; j0 = j) { /* rowlen could be larger than number of rows m, so sum in batches */
1579:       for (; j < PetscMin(rowlen, j0 + m); j++) acols[j - j0] = cdest[aj[ai[i] + j]];
1580:       PetscCall(MatSetValues(Aperm, 1, &rdest[i], j - j0, acols, aa + ai[i] + j0, INSERT_VALUES));
1581:     }
1582:     rowlen = bi[i + 1] - bi[i];
1583:     for (j0 = j = 0; j < rowlen; j0 = j) {
1584:       for (; j < PetscMin(rowlen, j0 + m); j++) bcols[j - j0] = gcdest[bj[bi[i] + j]];
1585:       PetscCall(MatSetValues(Aperm, 1, &rdest[i], j - j0, bcols, ba + bi[i] + j0, INSERT_VALUES));
1586:     }
1587:   }
1588:   PetscCall(MatAssemblyBegin(Aperm, MAT_FINAL_ASSEMBLY));
1589:   PetscCall(MatAssemblyEnd(Aperm, MAT_FINAL_ASSEMBLY));
1590:   PetscCall(MatRestoreRowIJ(aA, 0, PETSC_FALSE, PETSC_FALSE, &anz, &ai, &aj, &done));
1591:   PetscCall(MatRestoreRowIJ(aB, 0, PETSC_FALSE, PETSC_FALSE, &bnz, &bi, &bj, &done));
1592:   PetscCall(MatSeqAIJRestoreArray(aA, &aa));
1593:   PetscCall(MatSeqAIJRestoreArray(aB, &ba));
1594:   PetscCall(PetscFree4(dnnz, onnz, tdnnz, tonnz));
1595:   PetscCall(PetscFree3(work, rdest, cdest));
1596:   PetscCall(PetscFree(gcdest));
1597:   if (parcolp) PetscCall(ISDestroy(&colp));
1598:   *B = Aperm;
1599:   PetscFunctionReturn(PETSC_SUCCESS);
1600: }

1602: static PetscErrorCode MatGetGhosts_MPIAIJ(Mat mat, PetscInt *nghosts, const PetscInt *ghosts[])
1603: {
1604:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

1606:   PetscFunctionBegin;
1607:   PetscCall(MatGetSize(aij->B, NULL, nghosts));
1608:   if (ghosts) *ghosts = aij->garray;
1609:   PetscFunctionReturn(PETSC_SUCCESS);
1610: }

1612: static PetscErrorCode MatGetInfo_MPIAIJ(Mat matin, MatInfoType flag, MatInfo *info)
1613: {
1614:   Mat_MPIAIJ    *mat = (Mat_MPIAIJ *)matin->data;
1615:   Mat            A = mat->A, B = mat->B;
1616:   PetscLogDouble isend[5], irecv[5];

1618:   PetscFunctionBegin;
1619:   info->block_size = 1.0;
1620:   PetscCall(MatGetInfo(A, MAT_LOCAL, info));

1622:   isend[0] = info->nz_used;
1623:   isend[1] = info->nz_allocated;
1624:   isend[2] = info->nz_unneeded;
1625:   isend[3] = info->memory;
1626:   isend[4] = info->mallocs;

1628:   PetscCall(MatGetInfo(B, MAT_LOCAL, info));

1630:   isend[0] += info->nz_used;
1631:   isend[1] += info->nz_allocated;
1632:   isend[2] += info->nz_unneeded;
1633:   isend[3] += info->memory;
1634:   isend[4] += info->mallocs;
1635:   if (flag == MAT_LOCAL) {
1636:     info->nz_used      = isend[0];
1637:     info->nz_allocated = isend[1];
1638:     info->nz_unneeded  = isend[2];
1639:     info->memory       = isend[3];
1640:     info->mallocs      = isend[4];
1641:   } else if (flag == MAT_GLOBAL_MAX) {
1642:     PetscCallMPI(MPIU_Allreduce(isend, irecv, 5, MPIU_PETSCLOGDOUBLE, MPI_MAX, 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:   } else if (flag == MAT_GLOBAL_SUM) {
1650:     PetscCallMPI(MPIU_Allreduce(isend, irecv, 5, MPIU_PETSCLOGDOUBLE, MPI_SUM, PetscObjectComm((PetscObject)matin)));

1652:     info->nz_used      = irecv[0];
1653:     info->nz_allocated = irecv[1];
1654:     info->nz_unneeded  = irecv[2];
1655:     info->memory       = irecv[3];
1656:     info->mallocs      = irecv[4];
1657:   }
1658:   info->fill_ratio_given  = 0; /* no parallel LU/ILU/Cholesky */
1659:   info->fill_ratio_needed = 0;
1660:   info->factor_mallocs    = 0;
1661:   PetscFunctionReturn(PETSC_SUCCESS);
1662: }

1664: PetscErrorCode MatSetOption_MPIAIJ(Mat A, MatOption op, PetscBool flg)
1665: {
1666:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1668:   PetscFunctionBegin;
1669:   switch (op) {
1670:   case MAT_NEW_NONZERO_LOCATIONS:
1671:   case MAT_NEW_NONZERO_ALLOCATION_ERR:
1672:   case MAT_UNUSED_NONZERO_LOCATION_ERR:
1673:   case MAT_KEEP_NONZERO_PATTERN:
1674:   case MAT_NEW_NONZERO_LOCATION_ERR:
1675:   case MAT_USE_INODES:
1676:   case MAT_IGNORE_ZERO_ENTRIES:
1677:   case MAT_FORM_EXPLICIT_TRANSPOSE:
1678:     MatCheckPreallocated(A, 1);
1679:     PetscCall(MatSetOption(a->A, op, flg));
1680:     PetscCall(MatSetOption(a->B, op, flg));
1681:     break;
1682:   case MAT_ROW_ORIENTED:
1683:     MatCheckPreallocated(A, 1);
1684:     a->roworiented = flg;

1686:     PetscCall(MatSetOption(a->A, op, flg));
1687:     PetscCall(MatSetOption(a->B, op, flg));
1688:     break;
1689:   case MAT_IGNORE_OFF_PROC_ENTRIES:
1690:     a->donotstash = flg;
1691:     break;
1692:   /* Symmetry flags are handled directly by MatSetOption() and they don't affect preallocation */
1693:   case MAT_SPD:
1694:   case MAT_SYMMETRIC:
1695:   case MAT_STRUCTURALLY_SYMMETRIC:
1696:   case MAT_HERMITIAN:
1697:   case MAT_SYMMETRY_ETERNAL:
1698:   case MAT_STRUCTURAL_SYMMETRY_ETERNAL:
1699:   case MAT_SPD_ETERNAL:
1700:     /* if the diagonal matrix is square it inherits some of the properties above */
1701:     if (a->A && A->rmap->n == A->cmap->n) PetscCall(MatSetOption(a->A, op, flg));
1702:     break;
1703:   case MAT_SUBMAT_SINGLEIS:
1704:     A->submat_singleis = flg;
1705:     break;
1706:   default:
1707:     break;
1708:   }
1709:   PetscFunctionReturn(PETSC_SUCCESS);
1710: }

1712: PetscErrorCode MatGetRow_MPIAIJ(Mat matin, PetscInt row, PetscInt *nz, PetscInt **idx, PetscScalar **v)
1713: {
1714:   Mat_MPIAIJ  *mat = (Mat_MPIAIJ *)matin->data;
1715:   PetscScalar *vworkA, *vworkB, **pvA, **pvB, *v_p;
1716:   PetscInt     i, *cworkA, *cworkB, **pcA, **pcB, cstart = matin->cmap->rstart;
1717:   PetscInt     nztot, nzA, nzB, lrow, rstart = matin->rmap->rstart, rend = matin->rmap->rend;
1718:   PetscInt    *cmap, *idx_p;

1720:   PetscFunctionBegin;
1721:   PetscCheck(!mat->getrowactive, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Already active");
1722:   mat->getrowactive = PETSC_TRUE;

1724:   if (!mat->rowvalues && (idx || v)) {
1725:     /*
1726:         allocate enough space to hold information from the longest row.
1727:     */
1728:     Mat_SeqAIJ *Aa = (Mat_SeqAIJ *)mat->A->data, *Ba = (Mat_SeqAIJ *)mat->B->data;
1729:     PetscInt    max = 1, tmp;
1730:     for (i = 0; i < matin->rmap->n; i++) {
1731:       tmp = Aa->i[i + 1] - Aa->i[i] + Ba->i[i + 1] - Ba->i[i];
1732:       if (max < tmp) max = tmp;
1733:     }
1734:     PetscCall(PetscMalloc2(max, &mat->rowvalues, max, &mat->rowindices));
1735:   }

1737:   PetscCheck(row >= rstart && row < rend, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Only local rows");
1738:   lrow = row - rstart;

1740:   pvA = &vworkA;
1741:   pcA = &cworkA;
1742:   pvB = &vworkB;
1743:   pcB = &cworkB;
1744:   if (!v) {
1745:     pvA = NULL;
1746:     pvB = NULL;
1747:   }
1748:   if (!idx) {
1749:     pcA = NULL;
1750:     if (!v) pcB = NULL;
1751:   }
1752:   PetscCall((*mat->A->ops->getrow)(mat->A, lrow, &nzA, pcA, pvA));
1753:   PetscCall((*mat->B->ops->getrow)(mat->B, lrow, &nzB, pcB, pvB));
1754:   nztot = nzA + nzB;

1756:   cmap = mat->garray;
1757:   if (v || idx) {
1758:     if (nztot) {
1759:       /* Sort by increasing column numbers, assuming A and B already sorted */
1760:       PetscInt imark = -1;
1761:       if (v) {
1762:         *v = v_p = mat->rowvalues;
1763:         for (i = 0; i < nzB; i++) {
1764:           if (cmap[cworkB[i]] < cstart) v_p[i] = vworkB[i];
1765:           else break;
1766:         }
1767:         imark = i;
1768:         for (i = 0; i < nzA; i++) v_p[imark + i] = vworkA[i];
1769:         for (i = imark; i < nzB; i++) v_p[nzA + i] = vworkB[i];
1770:       }
1771:       if (idx) {
1772:         *idx = idx_p = mat->rowindices;
1773:         if (imark > -1) {
1774:           for (i = 0; i < imark; i++) idx_p[i] = cmap[cworkB[i]];
1775:         } else {
1776:           for (i = 0; i < nzB; i++) {
1777:             if (cmap[cworkB[i]] < cstart) idx_p[i] = cmap[cworkB[i]];
1778:             else break;
1779:           }
1780:           imark = i;
1781:         }
1782:         for (i = 0; i < nzA; i++) idx_p[imark + i] = cstart + cworkA[i];
1783:         for (i = imark; i < nzB; i++) idx_p[nzA + i] = cmap[cworkB[i]];
1784:       }
1785:     } else {
1786:       if (idx) *idx = NULL;
1787:       if (v) *v = NULL;
1788:     }
1789:   }
1790:   *nz = nztot;
1791:   PetscCall((*mat->A->ops->restorerow)(mat->A, lrow, &nzA, pcA, pvA));
1792:   PetscCall((*mat->B->ops->restorerow)(mat->B, lrow, &nzB, pcB, pvB));
1793:   PetscFunctionReturn(PETSC_SUCCESS);
1794: }

1796: PetscErrorCode MatRestoreRow_MPIAIJ(Mat mat, PetscInt row, PetscInt *nz, PetscInt **idx, PetscScalar **v)
1797: {
1798:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

1800:   PetscFunctionBegin;
1801:   PetscCheck(aij->getrowactive, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "MatGetRow() must be called first");
1802:   aij->getrowactive = PETSC_FALSE;
1803:   PetscFunctionReturn(PETSC_SUCCESS);
1804: }

1806: static PetscErrorCode MatNorm_MPIAIJ(Mat mat, NormType type, PetscReal *norm)
1807: {
1808:   Mat_MPIAIJ      *aij  = (Mat_MPIAIJ *)mat->data;
1809:   Mat_SeqAIJ      *amat = (Mat_SeqAIJ *)aij->A->data, *bmat = (Mat_SeqAIJ *)aij->B->data;
1810:   PetscInt         i, j, cstart = mat->cmap->rstart;
1811:   PetscReal        sum = 0.0;
1812:   const MatScalar *v, *amata, *bmata;

1814:   PetscFunctionBegin;
1815:   if (aij->size == 1) {
1816:     PetscCall(MatNorm(aij->A, type, norm));
1817:   } else {
1818:     PetscCall(MatSeqAIJGetArrayRead(aij->A, &amata));
1819:     PetscCall(MatSeqAIJGetArrayRead(aij->B, &bmata));
1820:     if (type == NORM_FROBENIUS) {
1821:       v = amata;
1822:       for (i = 0; i < amat->nz; i++) {
1823:         sum += PetscRealPart(PetscConj(*v) * (*v));
1824:         v++;
1825:       }
1826:       v = bmata;
1827:       for (i = 0; i < bmat->nz; i++) {
1828:         sum += PetscRealPart(PetscConj(*v) * (*v));
1829:         v++;
1830:       }
1831:       PetscCallMPI(MPIU_Allreduce(&sum, norm, 1, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)mat)));
1832:       *norm = PetscSqrtReal(*norm);
1833:       PetscCall(PetscLogFlops(2.0 * amat->nz + 2.0 * bmat->nz));
1834:     } else if (type == NORM_1) { /* max column norm */
1835:       PetscReal *tmp;
1836:       PetscInt  *jj, *garray = aij->garray;
1837:       PetscCall(PetscCalloc1(mat->cmap->N + 1, &tmp));
1838:       *norm = 0.0;
1839:       v     = amata;
1840:       jj    = amat->j;
1841:       for (j = 0; j < amat->nz; j++) {
1842:         tmp[cstart + *jj++] += PetscAbsScalar(*v);
1843:         v++;
1844:       }
1845:       v  = bmata;
1846:       jj = bmat->j;
1847:       for (j = 0; j < bmat->nz; j++) {
1848:         tmp[garray[*jj++]] += PetscAbsScalar(*v);
1849:         v++;
1850:       }
1851:       PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, tmp, mat->cmap->N, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)mat)));
1852:       for (j = 0; j < mat->cmap->N; j++) {
1853:         if (tmp[j] > *norm) *norm = tmp[j];
1854:       }
1855:       PetscCall(PetscFree(tmp));
1856:       PetscCall(PetscLogFlops(PetscMax(amat->nz + bmat->nz - 1, 0)));
1857:     } else if (type == NORM_INFINITY) { /* max row norm */
1858:       PetscReal ntemp = 0.0;
1859:       for (j = 0; j < aij->A->rmap->n; j++) {
1860:         v   = PetscSafePointerPlusOffset(amata, amat->i[j]);
1861:         sum = 0.0;
1862:         for (i = 0; i < amat->i[j + 1] - amat->i[j]; i++) {
1863:           sum += PetscAbsScalar(*v);
1864:           v++;
1865:         }
1866:         v = PetscSafePointerPlusOffset(bmata, bmat->i[j]);
1867:         for (i = 0; i < bmat->i[j + 1] - bmat->i[j]; i++) {
1868:           sum += PetscAbsScalar(*v);
1869:           v++;
1870:         }
1871:         if (sum > ntemp) ntemp = sum;
1872:       }
1873:       PetscCallMPI(MPIU_Allreduce(&ntemp, norm, 1, MPIU_REAL, MPIU_MAX, PetscObjectComm((PetscObject)mat)));
1874:       PetscCall(PetscLogFlops(PetscMax(amat->nz + bmat->nz - 1, 0)));
1875:     } else SETERRQ(PetscObjectComm((PetscObject)mat), PETSC_ERR_SUP, "No support for two norm");
1876:     PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &amata));
1877:     PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &bmata));
1878:   }
1879:   PetscFunctionReturn(PETSC_SUCCESS);
1880: }

1882: static PetscErrorCode MatTranspose_MPIAIJ(Mat A, MatReuse reuse, Mat *matout)
1883: {
1884:   Mat_MPIAIJ      *a    = (Mat_MPIAIJ *)A->data, *b;
1885:   Mat_SeqAIJ      *Aloc = (Mat_SeqAIJ *)a->A->data, *Bloc = (Mat_SeqAIJ *)a->B->data, *sub_B_diag;
1886:   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;
1887:   const PetscInt  *ai, *aj, *bi, *bj, *B_diag_i;
1888:   Mat              B, A_diag, *B_diag;
1889:   const MatScalar *pbv, *bv;

1891:   PetscFunctionBegin;
1892:   if (reuse == MAT_REUSE_MATRIX) PetscCall(MatTransposeCheckNonzeroState_Private(A, *matout));
1893:   ma = A->rmap->n;
1894:   na = A->cmap->n;
1895:   mb = a->B->rmap->n;
1896:   nb = a->B->cmap->n;
1897:   ai = Aloc->i;
1898:   aj = Aloc->j;
1899:   bi = Bloc->i;
1900:   bj = Bloc->j;
1901:   if (reuse == MAT_INITIAL_MATRIX || *matout == A) {
1902:     PetscInt            *d_nnz, *g_nnz, *o_nnz;
1903:     PetscSFNode         *oloc;
1904:     PETSC_UNUSED PetscSF sf;

1906:     PetscCall(PetscMalloc4(na, &d_nnz, na, &o_nnz, nb, &g_nnz, nb, &oloc));
1907:     /* compute d_nnz for preallocation */
1908:     PetscCall(PetscArrayzero(d_nnz, na));
1909:     for (i = 0; i < ai[ma]; i++) d_nnz[aj[i]]++;
1910:     /* compute local off-diagonal contributions */
1911:     PetscCall(PetscArrayzero(g_nnz, nb));
1912:     for (i = 0; i < bi[ma]; i++) g_nnz[bj[i]]++;
1913:     /* map those to global */
1914:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1915:     PetscCall(PetscSFSetGraphLayout(sf, A->cmap, nb, NULL, PETSC_USE_POINTER, a->garray));
1916:     PetscCall(PetscSFSetFromOptions(sf));
1917:     PetscCall(PetscArrayzero(o_nnz, na));
1918:     PetscCall(PetscSFReduceBegin(sf, MPIU_INT, g_nnz, o_nnz, MPI_SUM));
1919:     PetscCall(PetscSFReduceEnd(sf, MPIU_INT, g_nnz, o_nnz, MPI_SUM));
1920:     PetscCall(PetscSFDestroy(&sf));

1922:     PetscCall(MatCreate(PetscObjectComm((PetscObject)A), &B));
1923:     PetscCall(MatSetSizes(B, A->cmap->n, A->rmap->n, N, M));
1924:     PetscCall(MatSetBlockSizes(B, A->cmap->bs, A->rmap->bs));
1925:     PetscCall(MatSetType(B, ((PetscObject)A)->type_name));
1926:     PetscCall(MatMPIAIJSetPreallocation(B, 0, d_nnz, 0, o_nnz));
1927:     PetscCall(PetscFree4(d_nnz, o_nnz, g_nnz, oloc));
1928:   } else {
1929:     B = *matout;
1930:     PetscCall(MatSetOption(B, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_TRUE));
1931:   }

1933:   b           = (Mat_MPIAIJ *)B->data;
1934:   A_diag      = a->A;
1935:   B_diag      = &b->A;
1936:   sub_B_diag  = (Mat_SeqAIJ *)(*B_diag)->data;
1937:   A_diag_ncol = A_diag->cmap->N;
1938:   B_diag_ilen = sub_B_diag->ilen;
1939:   B_diag_i    = sub_B_diag->i;

1941:   /* Set ilen for diagonal of B */
1942:   for (i = 0; i < A_diag_ncol; i++) B_diag_ilen[i] = B_diag_i[i + 1] - B_diag_i[i];

1944:   /* Transpose the diagonal part of the matrix. In contrast to the off-diagonal part, this can be done
1945:   very quickly (=without using MatSetValues), because all writes are local. */
1946:   PetscCall(MatTransposeSetPrecursor(A_diag, *B_diag));
1947:   PetscCall(MatTranspose(A_diag, MAT_REUSE_MATRIX, B_diag));

1949:   /* copy over the B part */
1950:   PetscCall(PetscMalloc1(bi[mb], &cols));
1951:   PetscCall(MatSeqAIJGetArrayRead(a->B, &bv));
1952:   pbv = bv;
1953:   row = A->rmap->rstart;
1954:   for (i = 0; i < bi[mb]; i++) cols[i] = a->garray[bj[i]];
1955:   cols_tmp = cols;
1956:   for (i = 0; i < mb; i++) {
1957:     ncol = bi[i + 1] - bi[i];
1958:     PetscCall(MatSetValues(B, ncol, cols_tmp, 1, &row, pbv, INSERT_VALUES));
1959:     row++;
1960:     if (pbv) pbv += ncol;
1961:     if (cols_tmp) cols_tmp += ncol;
1962:   }
1963:   PetscCall(PetscFree(cols));
1964:   PetscCall(MatSeqAIJRestoreArrayRead(a->B, &bv));

1966:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
1967:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
1968:   if (reuse == MAT_INITIAL_MATRIX || reuse == MAT_REUSE_MATRIX) {
1969:     *matout = B;
1970:   } else {
1971:     PetscCall(MatHeaderMerge(A, &B));
1972:   }
1973:   PetscFunctionReturn(PETSC_SUCCESS);
1974: }

1976: static PetscErrorCode MatDiagonalScale_MPIAIJ(Mat mat, Vec ll, Vec rr)
1977: {
1978:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
1979:   Mat         a = aij->A, b = aij->B;
1980:   PetscInt    s1, s2, s3;

1982:   PetscFunctionBegin;
1983:   PetscCall(MatGetLocalSize(mat, &s2, &s3));
1984:   if (rr) {
1985:     PetscCall(VecGetLocalSize(rr, &s1));
1986:     PetscCheck(s1 == s3, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "right vector non-conforming local size");
1987:     /* Overlap communication with computation. */
1988:     PetscCall(VecScatterBegin(aij->Mvctx, rr, aij->lvec, INSERT_VALUES, SCATTER_FORWARD));
1989:   }
1990:   if (ll) {
1991:     PetscCall(VecGetLocalSize(ll, &s1));
1992:     PetscCheck(s1 == s2, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "left vector non-conforming local size");
1993:     PetscUseTypeMethod(b, diagonalscale, ll, NULL);
1994:   }
1995:   /* scale  the diagonal block */
1996:   PetscUseTypeMethod(a, diagonalscale, ll, rr);

1998:   if (rr) {
1999:     /* Do a scatter end and then right scale the off-diagonal block */
2000:     PetscCall(VecScatterEnd(aij->Mvctx, rr, aij->lvec, INSERT_VALUES, SCATTER_FORWARD));
2001:     PetscUseTypeMethod(b, diagonalscale, NULL, aij->lvec);
2002:   }
2003:   PetscFunctionReturn(PETSC_SUCCESS);
2004: }

2006: static PetscErrorCode MatSetUnfactored_MPIAIJ(Mat A)
2007: {
2008:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2010:   PetscFunctionBegin;
2011:   PetscCall(MatSetUnfactored(a->A));
2012:   PetscFunctionReturn(PETSC_SUCCESS);
2013: }

2015: static PetscErrorCode MatEqual_MPIAIJ(Mat A, Mat B, PetscBool *flag)
2016: {
2017:   Mat_MPIAIJ *matB = (Mat_MPIAIJ *)B->data, *matA = (Mat_MPIAIJ *)A->data;
2018:   Mat         a, b, c, d;
2019:   PetscBool   flg;

2021:   PetscFunctionBegin;
2022:   a = matA->A;
2023:   b = matA->B;
2024:   c = matB->A;
2025:   d = matB->B;

2027:   PetscCall(MatEqual(a, c, &flg));
2028:   if (flg) PetscCall(MatEqual(b, d, &flg));
2029:   PetscCallMPI(MPIU_Allreduce(&flg, flag, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)A)));
2030:   PetscFunctionReturn(PETSC_SUCCESS);
2031: }

2033: static PetscErrorCode MatCopy_MPIAIJ(Mat A, Mat B, MatStructure str)
2034: {
2035:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
2036:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;

2038:   PetscFunctionBegin;
2039:   /* If the two matrices don't have the same copy implementation, they aren't compatible for fast copy. */
2040:   if ((str != SAME_NONZERO_PATTERN) || (A->ops->copy != B->ops->copy)) {
2041:     /* because of the column compression in the off-processor part of the matrix a->B,
2042:        the number of columns in a->B and b->B may be different, hence we cannot call
2043:        the MatCopy() directly on the two parts. If need be, we can provide a more
2044:        efficient copy than the MatCopy_Basic() by first uncompressing the a->B matrices
2045:        then copying the submatrices */
2046:     PetscCall(MatCopy_Basic(A, B, str));
2047:   } else {
2048:     PetscCall(MatCopy(a->A, b->A, str));
2049:     PetscCall(MatCopy(a->B, b->B, str));
2050:   }
2051:   PetscCall(PetscObjectStateIncrease((PetscObject)B));
2052:   PetscFunctionReturn(PETSC_SUCCESS);
2053: }

2055: /*
2056:    Computes the number of nonzeros per row needed for preallocation when X and Y
2057:    have different nonzero structure.
2058: */
2059: 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)
2060: {
2061:   PetscInt i, j, k, nzx, nzy;

2063:   PetscFunctionBegin;
2064:   /* Set the number of nonzeros in the new matrix */
2065:   for (i = 0; i < m; i++) {
2066:     const PetscInt *xjj = PetscSafePointerPlusOffset(xj, xi[i]), *yjj = PetscSafePointerPlusOffset(yj, yi[i]);
2067:     nzx    = xi[i + 1] - xi[i];
2068:     nzy    = yi[i + 1] - yi[i];
2069:     nnz[i] = 0;
2070:     for (j = 0, k = 0; j < nzx; j++) {                                /* Point in X */
2071:       for (; k < nzy && yltog[yjj[k]] < xltog[xjj[j]]; k++) nnz[i]++; /* Catch up to X */
2072:       if (k < nzy && yltog[yjj[k]] == xltog[xjj[j]]) k++;             /* Skip duplicate */
2073:       nnz[i]++;
2074:     }
2075:     for (; k < nzy; k++) nnz[i]++;
2076:   }
2077:   PetscFunctionReturn(PETSC_SUCCESS);
2078: }

2080: /* This is the same as MatAXPYGetPreallocation_SeqAIJ, except that the local-to-global map is provided */
2081: static PetscErrorCode MatAXPYGetPreallocation_MPIAIJ(Mat Y, const PetscInt *yltog, Mat X, const PetscInt *xltog, PetscInt *nnz)
2082: {
2083:   PetscInt    m = Y->rmap->N;
2084:   Mat_SeqAIJ *x = (Mat_SeqAIJ *)X->data;
2085:   Mat_SeqAIJ *y = (Mat_SeqAIJ *)Y->data;

2087:   PetscFunctionBegin;
2088:   PetscCall(MatAXPYGetPreallocation_MPIX_private(m, x->i, x->j, xltog, y->i, y->j, yltog, nnz));
2089:   PetscFunctionReturn(PETSC_SUCCESS);
2090: }

2092: static PetscErrorCode MatAXPY_MPIAIJ(Mat Y, PetscScalar a, Mat X, MatStructure str)
2093: {
2094:   Mat_MPIAIJ *xx = (Mat_MPIAIJ *)X->data, *yy = (Mat_MPIAIJ *)Y->data;

2096:   PetscFunctionBegin;
2097:   if (str == SAME_NONZERO_PATTERN) {
2098:     PetscCall(MatAXPY(yy->A, a, xx->A, str));
2099:     PetscCall(MatAXPY(yy->B, a, xx->B, str));
2100:   } else if (str == SUBSET_NONZERO_PATTERN) { /* nonzeros of X is a subset of Y's */
2101:     PetscCall(MatAXPY_Basic(Y, a, X, str));
2102:   } else {
2103:     Mat       B;
2104:     PetscInt *nnz_d, *nnz_o;

2106:     PetscCall(PetscMalloc1(yy->A->rmap->N, &nnz_d));
2107:     PetscCall(PetscMalloc1(yy->B->rmap->N, &nnz_o));
2108:     PetscCall(MatCreate(PetscObjectComm((PetscObject)Y), &B));
2109:     PetscCall(PetscObjectSetName((PetscObject)B, ((PetscObject)Y)->name));
2110:     PetscCall(MatSetLayouts(B, Y->rmap, Y->cmap));
2111:     PetscCall(MatSetType(B, ((PetscObject)Y)->type_name));
2112:     PetscCall(MatAXPYGetPreallocation_SeqAIJ(yy->A, xx->A, nnz_d));
2113:     PetscCall(MatAXPYGetPreallocation_MPIAIJ(yy->B, yy->garray, xx->B, xx->garray, nnz_o));
2114:     PetscCall(MatMPIAIJSetPreallocation(B, 0, nnz_d, 0, nnz_o));
2115:     PetscCall(MatAXPY_BasicWithPreallocation(B, Y, a, X, str));
2116:     PetscCall(MatHeaderMerge(Y, &B));
2117:     PetscCall(PetscFree(nnz_d));
2118:     PetscCall(PetscFree(nnz_o));
2119:   }
2120:   PetscFunctionReturn(PETSC_SUCCESS);
2121: }

2123: PETSC_INTERN PetscErrorCode MatConjugate_SeqAIJ(Mat);

2125: static PetscErrorCode MatConjugate_MPIAIJ(Mat mat)
2126: {
2127:   PetscFunctionBegin;
2128:   if (PetscDefined(USE_COMPLEX)) {
2129:     Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2131:     PetscCall(MatConjugate_SeqAIJ(aij->A));
2132:     PetscCall(MatConjugate_SeqAIJ(aij->B));
2133:   }
2134:   PetscFunctionReturn(PETSC_SUCCESS);
2135: }

2137: static PetscErrorCode MatRealPart_MPIAIJ(Mat A)
2138: {
2139:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2141:   PetscFunctionBegin;
2142:   PetscCall(MatRealPart(a->A));
2143:   PetscCall(MatRealPart(a->B));
2144:   PetscFunctionReturn(PETSC_SUCCESS);
2145: }

2147: static PetscErrorCode MatImaginaryPart_MPIAIJ(Mat A)
2148: {
2149:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2151:   PetscFunctionBegin;
2152:   PetscCall(MatImaginaryPart(a->A));
2153:   PetscCall(MatImaginaryPart(a->B));
2154:   PetscFunctionReturn(PETSC_SUCCESS);
2155: }

2157: static PetscErrorCode MatGetRowMaxAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2158: {
2159:   Mat_MPIAIJ        *a = (Mat_MPIAIJ *)A->data;
2160:   PetscInt           i, *idxb = NULL, m = A->rmap->n;
2161:   PetscScalar       *vv;
2162:   Vec                vB, vA;
2163:   const PetscScalar *va, *vb;

2165:   PetscFunctionBegin;
2166:   PetscCall(MatCreateVecs(a->A, NULL, &vA));
2167:   PetscCall(MatGetRowMaxAbs(a->A, vA, idx));

2169:   PetscCall(VecGetArrayRead(vA, &va));
2170:   if (idx) {
2171:     for (i = 0; i < m; i++) {
2172:       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
2173:     }
2174:   }

2176:   PetscCall(MatCreateVecs(a->B, NULL, &vB));
2177:   PetscCall(PetscMalloc1(m, &idxb));
2178:   PetscCall(MatGetRowMaxAbs(a->B, vB, idxb));

2180:   PetscCall(VecGetArrayWrite(v, &vv));
2181:   PetscCall(VecGetArrayRead(vB, &vb));
2182:   for (i = 0; i < m; i++) {
2183:     if (PetscAbsScalar(va[i]) < PetscAbsScalar(vb[i])) {
2184:       vv[i] = vb[i];
2185:       if (idx) idx[i] = a->garray[idxb[i]];
2186:     } else {
2187:       vv[i] = va[i];
2188:       if (idx && PetscAbsScalar(va[i]) == PetscAbsScalar(vb[i]) && idxb[i] != -1 && idx[i] > a->garray[idxb[i]]) idx[i] = a->garray[idxb[i]];
2189:     }
2190:   }
2191:   PetscCall(VecRestoreArrayWrite(v, &vv));
2192:   PetscCall(VecRestoreArrayRead(vA, &va));
2193:   PetscCall(VecRestoreArrayRead(vB, &vb));
2194:   PetscCall(PetscFree(idxb));
2195:   PetscCall(VecDestroy(&vA));
2196:   PetscCall(VecDestroy(&vB));
2197:   PetscFunctionReturn(PETSC_SUCCESS);
2198: }

2200: static PetscErrorCode MatGetRowSumAbs_MPIAIJ(Mat A, Vec v)
2201: {
2202:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
2203:   Vec         vB, vA;

2205:   PetscFunctionBegin;
2206:   PetscCall(MatCreateVecs(a->A, NULL, &vA));
2207:   PetscCall(MatGetRowSumAbs(a->A, vA));
2208:   PetscCall(MatCreateVecs(a->B, NULL, &vB));
2209:   PetscCall(MatGetRowSumAbs(a->B, vB));
2210:   PetscCall(VecAXPY(vA, 1.0, vB));
2211:   PetscCall(VecDestroy(&vB));
2212:   PetscCall(VecCopy(vA, v));
2213:   PetscCall(VecDestroy(&vA));
2214:   PetscFunctionReturn(PETSC_SUCCESS);
2215: }

2217: static PetscErrorCode MatGetRowMinAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2218: {
2219:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2220:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2221:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2222:   PetscInt          *cmap = mat->garray;
2223:   PetscInt          *diagIdx, *offdiagIdx;
2224:   Vec                diagV, offdiagV;
2225:   PetscScalar       *a, *diagA, *offdiagA;
2226:   const PetscScalar *ba, *bav;
2227:   PetscInt           r, j, col, ncols, *bi, *bj;
2228:   Mat                B = mat->B;
2229:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2231:   PetscFunctionBegin;
2232:   /* When a process holds entire A and other processes have no entry */
2233:   if (A->cmap->N == n) {
2234:     PetscCall(VecGetArrayWrite(v, &diagA));
2235:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2236:     PetscCall(MatGetRowMinAbs(mat->A, diagV, idx));
2237:     PetscCall(VecDestroy(&diagV));
2238:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2239:     PetscFunctionReturn(PETSC_SUCCESS);
2240:   } else if (n == 0) {
2241:     if (m) {
2242:       PetscCall(VecGetArrayWrite(v, &a));
2243:       for (r = 0; r < m; r++) {
2244:         a[r] = 0.0;
2245:         if (idx) idx[r] = -1;
2246:       }
2247:       PetscCall(VecRestoreArrayWrite(v, &a));
2248:     }
2249:     PetscFunctionReturn(PETSC_SUCCESS);
2250:   }

2252:   PetscCall(PetscMalloc2(m, &diagIdx, m, &offdiagIdx));
2253:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2254:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2255:   PetscCall(MatGetRowMinAbs(mat->A, diagV, diagIdx));

2257:   /* Get offdiagIdx[] for implicit 0.0 */
2258:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2259:   ba = bav;
2260:   bi = b->i;
2261:   bj = b->j;
2262:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2263:   for (r = 0; r < m; r++) {
2264:     ncols = bi[r + 1] - bi[r];
2265:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2266:       offdiagA[r]   = *ba;
2267:       offdiagIdx[r] = cmap[0];
2268:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2269:       offdiagA[r] = 0.0;

2271:       /* Find first hole in the cmap */
2272:       for (j = 0; j < ncols; j++) {
2273:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2274:         if (col > j && j < cstart) {
2275:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2276:           break;
2277:         } else if (col > j + n && j >= cstart) {
2278:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2279:           break;
2280:         }
2281:       }
2282:       if (j == ncols && ncols < A->cmap->N - n) {
2283:         /* a hole is outside compressed Bcols */
2284:         if (ncols == 0) {
2285:           if (cstart) {
2286:             offdiagIdx[r] = 0;
2287:           } else offdiagIdx[r] = cend;
2288:         } else { /* ncols > 0 */
2289:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2290:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2291:         }
2292:       }
2293:     }

2295:     for (j = 0; j < ncols; j++) {
2296:       if (PetscAbsScalar(offdiagA[r]) > PetscAbsScalar(*ba)) {
2297:         offdiagA[r]   = *ba;
2298:         offdiagIdx[r] = cmap[*bj];
2299:       }
2300:       ba++;
2301:       bj++;
2302:     }
2303:   }

2305:   PetscCall(VecGetArrayWrite(v, &a));
2306:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2307:   for (r = 0; r < m; ++r) {
2308:     if (PetscAbsScalar(diagA[r]) < PetscAbsScalar(offdiagA[r])) {
2309:       a[r] = diagA[r];
2310:       if (idx) idx[r] = cstart + diagIdx[r];
2311:     } else if (PetscAbsScalar(diagA[r]) == PetscAbsScalar(offdiagA[r])) {
2312:       a[r] = diagA[r];
2313:       if (idx) {
2314:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2315:           idx[r] = cstart + diagIdx[r];
2316:         } else idx[r] = offdiagIdx[r];
2317:       }
2318:     } else {
2319:       a[r] = offdiagA[r];
2320:       if (idx) idx[r] = offdiagIdx[r];
2321:     }
2322:   }
2323:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2324:   PetscCall(VecRestoreArrayWrite(v, &a));
2325:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2326:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2327:   PetscCall(VecDestroy(&diagV));
2328:   PetscCall(VecDestroy(&offdiagV));
2329:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2330:   PetscFunctionReturn(PETSC_SUCCESS);
2331: }

2333: static PetscErrorCode MatGetRowMin_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2334: {
2335:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2336:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2337:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2338:   PetscInt          *cmap = mat->garray;
2339:   PetscInt          *diagIdx, *offdiagIdx;
2340:   Vec                diagV, offdiagV;
2341:   PetscScalar       *a, *diagA, *offdiagA;
2342:   const PetscScalar *ba, *bav;
2343:   PetscInt           r, j, col, ncols, *bi, *bj;
2344:   Mat                B = mat->B;
2345:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2347:   PetscFunctionBegin;
2348:   /* When a process holds entire A and other processes have no entry */
2349:   if (A->cmap->N == n) {
2350:     PetscCall(VecGetArrayWrite(v, &diagA));
2351:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2352:     PetscCall(MatGetRowMin(mat->A, diagV, idx));
2353:     PetscCall(VecDestroy(&diagV));
2354:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2355:     PetscFunctionReturn(PETSC_SUCCESS);
2356:   } else if (n == 0) {
2357:     if (m) {
2358:       PetscCall(VecGetArrayWrite(v, &a));
2359:       for (r = 0; r < m; r++) {
2360:         a[r] = PETSC_MAX_REAL;
2361:         if (idx) idx[r] = -1;
2362:       }
2363:       PetscCall(VecRestoreArrayWrite(v, &a));
2364:     }
2365:     PetscFunctionReturn(PETSC_SUCCESS);
2366:   }

2368:   PetscCall(PetscCalloc2(m, &diagIdx, m, &offdiagIdx));
2369:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2370:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2371:   PetscCall(MatGetRowMin(mat->A, diagV, diagIdx));

2373:   /* Get offdiagIdx[] for implicit 0.0 */
2374:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2375:   ba = bav;
2376:   bi = b->i;
2377:   bj = b->j;
2378:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2379:   for (r = 0; r < m; r++) {
2380:     ncols = bi[r + 1] - bi[r];
2381:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2382:       offdiagA[r]   = *ba;
2383:       offdiagIdx[r] = cmap[0];
2384:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2385:       offdiagA[r] = 0.0;

2387:       /* Find first hole in the cmap */
2388:       for (j = 0; j < ncols; j++) {
2389:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2390:         if (col > j && j < cstart) {
2391:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2392:           break;
2393:         } else if (col > j + n && j >= cstart) {
2394:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2395:           break;
2396:         }
2397:       }
2398:       if (j == ncols && ncols < A->cmap->N - n) {
2399:         /* a hole is outside compressed Bcols */
2400:         if (ncols == 0) {
2401:           if (cstart) {
2402:             offdiagIdx[r] = 0;
2403:           } else offdiagIdx[r] = cend;
2404:         } else { /* ncols > 0 */
2405:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2406:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2407:         }
2408:       }
2409:     }

2411:     for (j = 0; j < ncols; j++) {
2412:       if (PetscRealPart(offdiagA[r]) > PetscRealPart(*ba)) {
2413:         offdiagA[r]   = *ba;
2414:         offdiagIdx[r] = cmap[*bj];
2415:       }
2416:       ba++;
2417:       bj++;
2418:     }
2419:   }

2421:   PetscCall(VecGetArrayWrite(v, &a));
2422:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2423:   for (r = 0; r < m; ++r) {
2424:     if (PetscRealPart(diagA[r]) < PetscRealPart(offdiagA[r])) {
2425:       a[r] = diagA[r];
2426:       if (idx) idx[r] = cstart + diagIdx[r];
2427:     } else if (PetscRealPart(diagA[r]) == PetscRealPart(offdiagA[r])) {
2428:       a[r] = diagA[r];
2429:       if (idx) {
2430:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2431:           idx[r] = cstart + diagIdx[r];
2432:         } else idx[r] = offdiagIdx[r];
2433:       }
2434:     } else {
2435:       a[r] = offdiagA[r];
2436:       if (idx) idx[r] = offdiagIdx[r];
2437:     }
2438:   }
2439:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2440:   PetscCall(VecRestoreArrayWrite(v, &a));
2441:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2442:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2443:   PetscCall(VecDestroy(&diagV));
2444:   PetscCall(VecDestroy(&offdiagV));
2445:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2446:   PetscFunctionReturn(PETSC_SUCCESS);
2447: }

2449: static PetscErrorCode MatGetRowMax_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2450: {
2451:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2452:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2453:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2454:   PetscInt          *cmap = mat->garray;
2455:   PetscInt          *diagIdx, *offdiagIdx;
2456:   Vec                diagV, offdiagV;
2457:   PetscScalar       *a, *diagA, *offdiagA;
2458:   const PetscScalar *ba, *bav;
2459:   PetscInt           r, j, col, ncols, *bi, *bj;
2460:   Mat                B = mat->B;
2461:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2463:   PetscFunctionBegin;
2464:   /* When a process holds entire A and other processes have no entry */
2465:   if (A->cmap->N == n) {
2466:     PetscCall(VecGetArrayWrite(v, &diagA));
2467:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2468:     PetscCall(MatGetRowMax(mat->A, diagV, idx));
2469:     PetscCall(VecDestroy(&diagV));
2470:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2471:     PetscFunctionReturn(PETSC_SUCCESS);
2472:   } else if (n == 0) {
2473:     if (m) {
2474:       PetscCall(VecGetArrayWrite(v, &a));
2475:       for (r = 0; r < m; r++) {
2476:         a[r] = PETSC_MIN_REAL;
2477:         if (idx) idx[r] = -1;
2478:       }
2479:       PetscCall(VecRestoreArrayWrite(v, &a));
2480:     }
2481:     PetscFunctionReturn(PETSC_SUCCESS);
2482:   }

2484:   PetscCall(PetscMalloc2(m, &diagIdx, m, &offdiagIdx));
2485:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2486:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2487:   PetscCall(MatGetRowMax(mat->A, diagV, diagIdx));

2489:   /* Get offdiagIdx[] for implicit 0.0 */
2490:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2491:   ba = bav;
2492:   bi = b->i;
2493:   bj = b->j;
2494:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2495:   for (r = 0; r < m; r++) {
2496:     ncols = bi[r + 1] - bi[r];
2497:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2498:       offdiagA[r]   = *ba;
2499:       offdiagIdx[r] = cmap[0];
2500:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2501:       offdiagA[r] = 0.0;

2503:       /* Find first hole in the cmap */
2504:       for (j = 0; j < ncols; j++) {
2505:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2506:         if (col > j && j < cstart) {
2507:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2508:           break;
2509:         } else if (col > j + n && j >= cstart) {
2510:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2511:           break;
2512:         }
2513:       }
2514:       if (j == ncols && ncols < A->cmap->N - n) {
2515:         /* a hole is outside compressed Bcols */
2516:         if (ncols == 0) {
2517:           if (cstart) {
2518:             offdiagIdx[r] = 0;
2519:           } else offdiagIdx[r] = cend;
2520:         } else { /* ncols > 0 */
2521:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2522:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2523:         }
2524:       }
2525:     }

2527:     for (j = 0; j < ncols; j++) {
2528:       if (PetscRealPart(offdiagA[r]) < PetscRealPart(*ba)) {
2529:         offdiagA[r]   = *ba;
2530:         offdiagIdx[r] = cmap[*bj];
2531:       }
2532:       ba++;
2533:       bj++;
2534:     }
2535:   }

2537:   PetscCall(VecGetArrayWrite(v, &a));
2538:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2539:   for (r = 0; r < m; ++r) {
2540:     if (PetscRealPart(diagA[r]) > PetscRealPart(offdiagA[r])) {
2541:       a[r] = diagA[r];
2542:       if (idx) idx[r] = cstart + diagIdx[r];
2543:     } else if (PetscRealPart(diagA[r]) == PetscRealPart(offdiagA[r])) {
2544:       a[r] = diagA[r];
2545:       if (idx) {
2546:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2547:           idx[r] = cstart + diagIdx[r];
2548:         } else idx[r] = offdiagIdx[r];
2549:       }
2550:     } else {
2551:       a[r] = offdiagA[r];
2552:       if (idx) idx[r] = offdiagIdx[r];
2553:     }
2554:   }
2555:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2556:   PetscCall(VecRestoreArrayWrite(v, &a));
2557:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2558:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2559:   PetscCall(VecDestroy(&diagV));
2560:   PetscCall(VecDestroy(&offdiagV));
2561:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2562:   PetscFunctionReturn(PETSC_SUCCESS);
2563: }

2565: PetscErrorCode MatGetSeqNonzeroStructure_MPIAIJ(Mat mat, Mat *newmat)
2566: {
2567:   Mat *dummy;

2569:   PetscFunctionBegin;
2570:   PetscCall(MatCreateSubMatrix_MPIAIJ_All(mat, MAT_DO_NOT_GET_VALUES, MAT_INITIAL_MATRIX, &dummy));
2571:   *newmat = *dummy;
2572:   PetscCall(PetscFree(dummy));
2573:   PetscFunctionReturn(PETSC_SUCCESS);
2574: }

2576: static PetscErrorCode MatInvertBlockDiagonal_MPIAIJ(Mat A, const PetscScalar **values)
2577: {
2578:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2580:   PetscFunctionBegin;
2581:   PetscCall(MatInvertBlockDiagonal(a->A, values));
2582:   A->factorerrortype = a->A->factorerrortype;
2583:   PetscFunctionReturn(PETSC_SUCCESS);
2584: }

2586: static PetscErrorCode MatSetRandom_MPIAIJ(Mat x, PetscRandom rctx)
2587: {
2588:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)x->data;

2590:   PetscFunctionBegin;
2591:   PetscCheck(x->assembled || x->preallocated, PetscObjectComm((PetscObject)x), PETSC_ERR_ARG_WRONGSTATE, "MatSetRandom on an unassembled and unpreallocated MATMPIAIJ is not allowed");
2592:   PetscCall(MatSetRandom(aij->A, rctx));
2593:   if (x->assembled) {
2594:     PetscCall(MatSetRandom(aij->B, rctx));
2595:   } else {
2596:     PetscCall(MatSetRandomSkipColumnRange_SeqAIJ_Private(aij->B, x->cmap->rstart, x->cmap->rend, rctx));
2597:   }
2598:   PetscCall(MatAssemblyBegin(x, MAT_FINAL_ASSEMBLY));
2599:   PetscCall(MatAssemblyEnd(x, MAT_FINAL_ASSEMBLY));
2600:   PetscFunctionReturn(PETSC_SUCCESS);
2601: }

2603: static PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ(Mat A, PetscBool sc)
2604: {
2605:   PetscFunctionBegin;
2606:   if (sc) A->ops->increaseoverlap = MatIncreaseOverlap_MPIAIJ_Scalable;
2607:   else A->ops->increaseoverlap = MatIncreaseOverlap_MPIAIJ;
2608:   PetscFunctionReturn(PETSC_SUCCESS);
2609: }

2611: /*@
2612:   MatMPIAIJGetNumberNonzeros - gets the number of nonzeros in the matrix on this MPI rank

2614:   Not Collective

2616:   Input Parameter:
2617: . A - the matrix

2619:   Output Parameter:
2620: . nz - the number of nonzeros

2622:   Level: advanced

2624: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`
2625: @*/
2626: PetscErrorCode MatMPIAIJGetNumberNonzeros(Mat A, PetscCount *nz)
2627: {
2628:   Mat_MPIAIJ *maij = (Mat_MPIAIJ *)A->data;
2629:   Mat_SeqAIJ *aaij = (Mat_SeqAIJ *)maij->A->data, *baij = (Mat_SeqAIJ *)maij->B->data;
2630:   PetscBool   isaij;

2632:   PetscFunctionBegin;
2633:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)A, MATMPIAIJ, &isaij));
2634:   PetscCheck(isaij, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Not for type %s", ((PetscObject)A)->type_name);
2635:   *nz = aaij->i[A->rmap->n] + baij->i[A->rmap->n];
2636:   PetscFunctionReturn(PETSC_SUCCESS);
2637: }

2639: /*@
2640:   MatMPIAIJSetUseScalableIncreaseOverlap - Determine if the matrix uses a scalable algorithm to compute the overlap

2642:   Collective

2644:   Input Parameters:
2645: + A  - the matrix
2646: - sc - `PETSC_TRUE` indicates use the scalable algorithm (default is not to use the scalable algorithm)

2648:   Level: advanced

2650: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`
2651: @*/
2652: PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap(Mat A, PetscBool sc)
2653: {
2654:   PetscFunctionBegin;
2655:   PetscTryMethod(A, "MatMPIAIJSetUseScalableIncreaseOverlap_C", (Mat, PetscBool), (A, sc));
2656:   PetscFunctionReturn(PETSC_SUCCESS);
2657: }

2659: PetscErrorCode MatSetFromOptions_MPIAIJ(Mat A, PetscOptionItems PetscOptionsObject)
2660: {
2661:   PetscBool sc = PETSC_FALSE, flg;

2663:   PetscFunctionBegin;
2664:   PetscOptionsHeadBegin(PetscOptionsObject, "MPIAIJ options");
2665:   if (A->ops->increaseoverlap == MatIncreaseOverlap_MPIAIJ_Scalable) sc = PETSC_TRUE;
2666:   PetscCall(PetscOptionsBool("-mat_increase_overlap_scalable", "Use a scalable algorithm to compute the overlap", "MatIncreaseOverlap", sc, &sc, &flg));
2667:   if (flg) PetscCall(MatMPIAIJSetUseScalableIncreaseOverlap(A, sc));
2668:   PetscOptionsHeadEnd();
2669:   PetscFunctionReturn(PETSC_SUCCESS);
2670: }

2672: static PetscErrorCode MatShift_MPIAIJ(Mat Y, PetscScalar a)
2673: {
2674:   Mat_MPIAIJ *maij = (Mat_MPIAIJ *)Y->data;
2675:   Mat_SeqAIJ *aij  = (Mat_SeqAIJ *)maij->A->data;

2677:   PetscFunctionBegin;
2678:   if (!Y->preallocated) {
2679:     PetscCall(MatMPIAIJSetPreallocation(Y, 1, NULL, 0, NULL));
2680:   } else if (!aij->nz) { /* It does not matter if diagonals of Y only partially lie in maij->A. We just need an estimated preallocation. */
2681:     PetscInt nonew = aij->nonew;
2682:     PetscCall(MatSeqAIJSetPreallocation(maij->A, 1, NULL));
2683:     aij->nonew = nonew;
2684:   }
2685:   PetscCall(MatShift_Basic(Y, a));
2686:   PetscFunctionReturn(PETSC_SUCCESS);
2687: }

2689: static PetscErrorCode MatMissingDiagonal_MPIAIJ(Mat A, PetscBool *missing, PetscInt *d)
2690: {
2691:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2693:   PetscFunctionBegin;
2694:   PetscCheck(A->rmap->n == A->cmap->n, PETSC_COMM_SELF, PETSC_ERR_SUP, "Only works for square matrices");
2695:   PetscCall(MatMissingDiagonal(a->A, missing, d));
2696:   if (d) {
2697:     PetscInt rstart;
2698:     PetscCall(MatGetOwnershipRange(A, &rstart, NULL));
2699:     *d += rstart;
2700:   }
2701:   PetscFunctionReturn(PETSC_SUCCESS);
2702: }

2704: static PetscErrorCode MatInvertVariableBlockDiagonal_MPIAIJ(Mat A, PetscInt nblocks, const PetscInt *bsizes, PetscScalar *diag)
2705: {
2706:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2708:   PetscFunctionBegin;
2709:   PetscCall(MatInvertVariableBlockDiagonal(a->A, nblocks, bsizes, diag));
2710:   PetscFunctionReturn(PETSC_SUCCESS);
2711: }

2713: static PetscErrorCode MatEliminateZeros_MPIAIJ(Mat A, PetscBool keep)
2714: {
2715:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2717:   PetscFunctionBegin;
2718:   PetscCall(MatEliminateZeros_SeqAIJ(a->A, keep));        // possibly keep zero diagonal coefficients
2719:   PetscCall(MatEliminateZeros_SeqAIJ(a->B, PETSC_FALSE)); // never keep zero diagonal coefficients
2720:   PetscFunctionReturn(PETSC_SUCCESS);
2721: }

2723: static struct _MatOps MatOps_Values = {MatSetValues_MPIAIJ,
2724:                                        MatGetRow_MPIAIJ,
2725:                                        MatRestoreRow_MPIAIJ,
2726:                                        MatMult_MPIAIJ,
2727:                                        /* 4*/ MatMultAdd_MPIAIJ,
2728:                                        MatMultTranspose_MPIAIJ,
2729:                                        MatMultTransposeAdd_MPIAIJ,
2730:                                        NULL,
2731:                                        NULL,
2732:                                        NULL,
2733:                                        /*10*/ NULL,
2734:                                        NULL,
2735:                                        NULL,
2736:                                        MatSOR_MPIAIJ,
2737:                                        MatTranspose_MPIAIJ,
2738:                                        /*15*/ MatGetInfo_MPIAIJ,
2739:                                        MatEqual_MPIAIJ,
2740:                                        MatGetDiagonal_MPIAIJ,
2741:                                        MatDiagonalScale_MPIAIJ,
2742:                                        MatNorm_MPIAIJ,
2743:                                        /*20*/ MatAssemblyBegin_MPIAIJ,
2744:                                        MatAssemblyEnd_MPIAIJ,
2745:                                        MatSetOption_MPIAIJ,
2746:                                        MatZeroEntries_MPIAIJ,
2747:                                        /*24*/ MatZeroRows_MPIAIJ,
2748:                                        NULL,
2749:                                        NULL,
2750:                                        NULL,
2751:                                        NULL,
2752:                                        /*29*/ MatSetUp_MPI_Hash,
2753:                                        NULL,
2754:                                        NULL,
2755:                                        MatGetDiagonalBlock_MPIAIJ,
2756:                                        NULL,
2757:                                        /*34*/ MatDuplicate_MPIAIJ,
2758:                                        NULL,
2759:                                        NULL,
2760:                                        NULL,
2761:                                        NULL,
2762:                                        /*39*/ MatAXPY_MPIAIJ,
2763:                                        MatCreateSubMatrices_MPIAIJ,
2764:                                        MatIncreaseOverlap_MPIAIJ,
2765:                                        MatGetValues_MPIAIJ,
2766:                                        MatCopy_MPIAIJ,
2767:                                        /*44*/ MatGetRowMax_MPIAIJ,
2768:                                        MatScale_MPIAIJ,
2769:                                        MatShift_MPIAIJ,
2770:                                        MatDiagonalSet_MPIAIJ,
2771:                                        MatZeroRowsColumns_MPIAIJ,
2772:                                        /*49*/ MatSetRandom_MPIAIJ,
2773:                                        MatGetRowIJ_MPIAIJ,
2774:                                        MatRestoreRowIJ_MPIAIJ,
2775:                                        NULL,
2776:                                        NULL,
2777:                                        /*54*/ MatFDColoringCreate_MPIXAIJ,
2778:                                        NULL,
2779:                                        MatSetUnfactored_MPIAIJ,
2780:                                        MatPermute_MPIAIJ,
2781:                                        NULL,
2782:                                        /*59*/ MatCreateSubMatrix_MPIAIJ,
2783:                                        MatDestroy_MPIAIJ,
2784:                                        MatView_MPIAIJ,
2785:                                        NULL,
2786:                                        NULL,
2787:                                        /*64*/ MatMatMatMultNumeric_MPIAIJ_MPIAIJ_MPIAIJ,
2788:                                        NULL,
2789:                                        NULL,
2790:                                        NULL,
2791:                                        MatGetRowMaxAbs_MPIAIJ,
2792:                                        /*69*/ MatGetRowMinAbs_MPIAIJ,
2793:                                        NULL,
2794:                                        NULL,
2795:                                        MatFDColoringApply_AIJ,
2796:                                        MatSetFromOptions_MPIAIJ,
2797:                                        MatFindZeroDiagonals_MPIAIJ,
2798:                                        /*75*/ NULL,
2799:                                        NULL,
2800:                                        NULL,
2801:                                        MatLoad_MPIAIJ,
2802:                                        NULL,
2803:                                        /*80*/ NULL,
2804:                                        NULL,
2805:                                        NULL,
2806:                                        /*83*/ NULL,
2807:                                        NULL,
2808:                                        MatMatMultNumeric_MPIAIJ_MPIAIJ,
2809:                                        MatPtAPNumeric_MPIAIJ_MPIAIJ,
2810:                                        NULL,
2811:                                        NULL,
2812:                                        /*89*/ MatBindToCPU_MPIAIJ,
2813:                                        MatProductSetFromOptions_MPIAIJ,
2814:                                        NULL,
2815:                                        NULL,
2816:                                        MatConjugate_MPIAIJ,
2817:                                        /*94*/ NULL,
2818:                                        MatSetValuesRow_MPIAIJ,
2819:                                        MatRealPart_MPIAIJ,
2820:                                        MatImaginaryPart_MPIAIJ,
2821:                                        NULL,
2822:                                        /*99*/ NULL,
2823:                                        NULL,
2824:                                        NULL,
2825:                                        MatGetRowMin_MPIAIJ,
2826:                                        NULL,
2827:                                        /*104*/ MatMissingDiagonal_MPIAIJ,
2828:                                        MatGetSeqNonzeroStructure_MPIAIJ,
2829:                                        NULL,
2830:                                        MatGetGhosts_MPIAIJ,
2831:                                        NULL,
2832:                                        /*109*/ NULL,
2833:                                        MatMultDiagonalBlock_MPIAIJ,
2834:                                        NULL,
2835:                                        NULL,
2836:                                        NULL,
2837:                                        /*114*/ MatGetMultiProcBlock_MPIAIJ,
2838:                                        MatFindNonzeroRows_MPIAIJ,
2839:                                        MatGetColumnReductions_MPIAIJ,
2840:                                        MatInvertBlockDiagonal_MPIAIJ,
2841:                                        MatInvertVariableBlockDiagonal_MPIAIJ,
2842:                                        /*119*/ MatCreateSubMatricesMPI_MPIAIJ,
2843:                                        NULL,
2844:                                        NULL,
2845:                                        MatTransposeMatMultNumeric_MPIAIJ_MPIAIJ,
2846:                                        NULL,
2847:                                        /*124*/ NULL,
2848:                                        NULL,
2849:                                        NULL,
2850:                                        MatSetBlockSizes_MPIAIJ,
2851:                                        NULL,
2852:                                        /*129*/ MatFDColoringSetUp_MPIXAIJ,
2853:                                        MatFindOffBlockDiagonalEntries_MPIAIJ,
2854:                                        MatCreateMPIMatConcatenateSeqMat_MPIAIJ,
2855:                                        NULL,
2856:                                        NULL,
2857:                                        /*134*/ NULL,
2858:                                        MatCreateGraph_Simple_AIJ,
2859:                                        NULL,
2860:                                        MatEliminateZeros_MPIAIJ,
2861:                                        MatGetRowSumAbs_MPIAIJ,
2862:                                        /*139*/ NULL,
2863:                                        NULL,
2864:                                        NULL,
2865:                                        MatCopyHashToXAIJ_MPI_Hash,
2866:                                        MatGetCurrentMemType_MPIAIJ};

2868: static PetscErrorCode MatStoreValues_MPIAIJ(Mat mat)
2869: {
2870:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2872:   PetscFunctionBegin;
2873:   PetscCall(MatStoreValues(aij->A));
2874:   PetscCall(MatStoreValues(aij->B));
2875:   PetscFunctionReturn(PETSC_SUCCESS);
2876: }

2878: static PetscErrorCode MatRetrieveValues_MPIAIJ(Mat mat)
2879: {
2880:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2882:   PetscFunctionBegin;
2883:   PetscCall(MatRetrieveValues(aij->A));
2884:   PetscCall(MatRetrieveValues(aij->B));
2885:   PetscFunctionReturn(PETSC_SUCCESS);
2886: }

2888: PetscErrorCode MatMPIAIJSetPreallocation_MPIAIJ(Mat B, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[])
2889: {
2890:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;
2891:   PetscMPIInt size;

2893:   PetscFunctionBegin;
2894:   if (B->hash_active) {
2895:     B->ops[0]      = b->cops;
2896:     B->hash_active = PETSC_FALSE;
2897:   }
2898:   PetscCall(PetscLayoutSetUp(B->rmap));
2899:   PetscCall(PetscLayoutSetUp(B->cmap));

2901: #if defined(PETSC_USE_CTABLE)
2902:   PetscCall(PetscHMapIDestroy(&b->colmap));
2903: #else
2904:   PetscCall(PetscFree(b->colmap));
2905: #endif
2906:   PetscCall(PetscFree(b->garray));
2907:   PetscCall(VecDestroy(&b->lvec));
2908:   PetscCall(VecScatterDestroy(&b->Mvctx));

2910:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)B), &size));

2912:   MatSeqXAIJGetOptions_Private(b->B);
2913:   PetscCall(MatDestroy(&b->B));
2914:   PetscCall(MatCreate(PETSC_COMM_SELF, &b->B));
2915:   PetscCall(MatSetSizes(b->B, B->rmap->n, size > 1 ? B->cmap->N : 0, B->rmap->n, size > 1 ? B->cmap->N : 0));
2916:   PetscCall(MatSetBlockSizesFromMats(b->B, B, B));
2917:   PetscCall(MatSetType(b->B, MATSEQAIJ));
2918:   MatSeqXAIJRestoreOptions_Private(b->B);

2920:   MatSeqXAIJGetOptions_Private(b->A);
2921:   PetscCall(MatDestroy(&b->A));
2922:   PetscCall(MatCreate(PETSC_COMM_SELF, &b->A));
2923:   PetscCall(MatSetSizes(b->A, B->rmap->n, B->cmap->n, B->rmap->n, B->cmap->n));
2924:   PetscCall(MatSetBlockSizesFromMats(b->A, B, B));
2925:   PetscCall(MatSetType(b->A, MATSEQAIJ));
2926:   MatSeqXAIJRestoreOptions_Private(b->A);

2928:   PetscCall(MatSeqAIJSetPreallocation(b->A, d_nz, d_nnz));
2929:   PetscCall(MatSeqAIJSetPreallocation(b->B, o_nz, o_nnz));
2930:   B->preallocated  = PETSC_TRUE;
2931:   B->was_assembled = PETSC_FALSE;
2932:   B->assembled     = PETSC_FALSE;
2933:   PetscFunctionReturn(PETSC_SUCCESS);
2934: }

2936: static PetscErrorCode MatResetPreallocation_MPIAIJ(Mat B)
2937: {
2938:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;
2939:   PetscBool   ondiagreset, offdiagreset, memoryreset;

2941:   PetscFunctionBegin;
2943:   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()");
2944:   if (B->num_ass == 0) PetscFunctionReturn(PETSC_SUCCESS);

2946:   PetscCall(MatResetPreallocation_SeqAIJ_Private(b->A, &ondiagreset));
2947:   PetscCall(MatResetPreallocation_SeqAIJ_Private(b->B, &offdiagreset));
2948:   memoryreset = (PetscBool)(ondiagreset || offdiagreset);
2949:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &memoryreset, 1, MPIU_BOOL, MPI_LOR, PetscObjectComm((PetscObject)B)));
2950:   if (!memoryreset) PetscFunctionReturn(PETSC_SUCCESS);

2952:   PetscCall(PetscLayoutSetUp(B->rmap));
2953:   PetscCall(PetscLayoutSetUp(B->cmap));
2954:   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");
2955:   PetscCall(MatDisAssemble_MPIAIJ(B, PETSC_TRUE));
2956:   PetscCall(VecScatterDestroy(&b->Mvctx));

2958:   B->preallocated  = PETSC_TRUE;
2959:   B->was_assembled = PETSC_FALSE;
2960:   B->assembled     = PETSC_FALSE;
2961:   /* Log that the state of this object has changed; this will help guarantee that preconditioners get re-setup */
2962:   PetscCall(PetscObjectStateIncrease((PetscObject)B));
2963:   PetscFunctionReturn(PETSC_SUCCESS);
2964: }

2966: PetscErrorCode MatDuplicate_MPIAIJ(Mat matin, MatDuplicateOption cpvalues, Mat *newmat)
2967: {
2968:   Mat         mat;
2969:   Mat_MPIAIJ *a, *oldmat = (Mat_MPIAIJ *)matin->data;

2971:   PetscFunctionBegin;
2972:   *newmat = NULL;
2973:   PetscCall(MatCreate(PetscObjectComm((PetscObject)matin), &mat));
2974:   PetscCall(MatSetSizes(mat, matin->rmap->n, matin->cmap->n, matin->rmap->N, matin->cmap->N));
2975:   PetscCall(MatSetBlockSizesFromMats(mat, matin, matin));
2976:   PetscCall(MatSetType(mat, ((PetscObject)matin)->type_name));
2977:   a = (Mat_MPIAIJ *)mat->data;

2979:   mat->factortype = matin->factortype;
2980:   mat->assembled  = matin->assembled;
2981:   mat->insertmode = NOT_SET_VALUES;

2983:   a->size         = oldmat->size;
2984:   a->rank         = oldmat->rank;
2985:   a->donotstash   = oldmat->donotstash;
2986:   a->roworiented  = oldmat->roworiented;
2987:   a->rowindices   = NULL;
2988:   a->rowvalues    = NULL;
2989:   a->getrowactive = PETSC_FALSE;

2991:   PetscCall(PetscLayoutReference(matin->rmap, &mat->rmap));
2992:   PetscCall(PetscLayoutReference(matin->cmap, &mat->cmap));
2993:   if (matin->hash_active) {
2994:     PetscCall(MatSetUp(mat));
2995:   } else {
2996:     mat->preallocated = matin->preallocated;
2997:     if (oldmat->colmap) {
2998: #if defined(PETSC_USE_CTABLE)
2999:       PetscCall(PetscHMapIDuplicate(oldmat->colmap, &a->colmap));
3000: #else
3001:       PetscCall(PetscMalloc1(mat->cmap->N, &a->colmap));
3002:       PetscCall(PetscArraycpy(a->colmap, oldmat->colmap, mat->cmap->N));
3003: #endif
3004:     } else a->colmap = NULL;
3005:     if (oldmat->garray) {
3006:       PetscInt len;
3007:       len = oldmat->B->cmap->n;
3008:       PetscCall(PetscMalloc1(len + 1, &a->garray));
3009:       if (len) PetscCall(PetscArraycpy(a->garray, oldmat->garray, len));
3010:     } else a->garray = NULL;

3012:     /* It may happen MatDuplicate is called with a non-assembled matrix
3013:       In fact, MatDuplicate only requires the matrix to be preallocated
3014:       This may happen inside a DMCreateMatrix_Shell */
3015:     if (oldmat->lvec) PetscCall(VecDuplicate(oldmat->lvec, &a->lvec));
3016:     if (oldmat->Mvctx) {
3017:       a->Mvctx = oldmat->Mvctx;
3018:       PetscCall(PetscObjectReference((PetscObject)oldmat->Mvctx));
3019:     }
3020:     PetscCall(MatDuplicate(oldmat->A, cpvalues, &a->A));
3021:     PetscCall(MatDuplicate(oldmat->B, cpvalues, &a->B));
3022:   }
3023:   PetscCall(PetscFunctionListDuplicate(((PetscObject)matin)->qlist, &((PetscObject)mat)->qlist));
3024:   *newmat = mat;
3025:   PetscFunctionReturn(PETSC_SUCCESS);
3026: }

3028: PetscErrorCode MatLoad_MPIAIJ(Mat newMat, PetscViewer viewer)
3029: {
3030:   PetscBool isbinary, ishdf5;

3032:   PetscFunctionBegin;
3035:   /* force binary viewer to load .info file if it has not yet done so */
3036:   PetscCall(PetscViewerSetUp(viewer));
3037:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
3038:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERHDF5, &ishdf5));
3039:   if (isbinary) {
3040:     PetscCall(MatLoad_MPIAIJ_Binary(newMat, viewer));
3041:   } else if (ishdf5) {
3042: #if defined(PETSC_HAVE_HDF5)
3043:     PetscCall(MatLoad_AIJ_HDF5(newMat, viewer));
3044: #else
3045:     SETERRQ(PetscObjectComm((PetscObject)newMat), PETSC_ERR_SUP, "HDF5 not supported in this build.\nPlease reconfigure using --download-hdf5");
3046: #endif
3047:   } else {
3048:     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);
3049:   }
3050:   PetscFunctionReturn(PETSC_SUCCESS);
3051: }

3053: PetscErrorCode MatLoad_MPIAIJ_Binary(Mat mat, PetscViewer viewer)
3054: {
3055:   PetscInt     header[4], M, N, m, nz, rows, cols, sum, i;
3056:   PetscInt    *rowidxs, *colidxs;
3057:   PetscScalar *matvals;

3059:   PetscFunctionBegin;
3060:   PetscCall(PetscViewerSetUp(viewer));

3062:   /* read in matrix header */
3063:   PetscCall(PetscViewerBinaryRead(viewer, header, 4, NULL, PETSC_INT));
3064:   PetscCheck(header[0] == MAT_FILE_CLASSID, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Not a matrix object in file");
3065:   M  = header[1];
3066:   N  = header[2];
3067:   nz = header[3];
3068:   PetscCheck(M >= 0, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Matrix row size (%" PetscInt_FMT ") in file is negative", M);
3069:   PetscCheck(N >= 0, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Matrix column size (%" PetscInt_FMT ") in file is negative", N);
3070:   PetscCheck(nz >= 0, PETSC_COMM_SELF, PETSC_ERR_FILE_UNEXPECTED, "Matrix stored in special format on disk, cannot load as MPIAIJ");

3072:   /* set block sizes from the viewer's .info file */
3073:   PetscCall(MatLoad_Binary_BlockSizes(mat, viewer));
3074:   /* set global sizes if not set already */
3075:   if (mat->rmap->N < 0) mat->rmap->N = M;
3076:   if (mat->cmap->N < 0) mat->cmap->N = N;
3077:   PetscCall(PetscLayoutSetUp(mat->rmap));
3078:   PetscCall(PetscLayoutSetUp(mat->cmap));

3080:   /* check if the matrix sizes are correct */
3081:   PetscCall(MatGetSize(mat, &rows, &cols));
3082:   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);

3084:   /* read in row lengths and build row indices */
3085:   PetscCall(MatGetLocalSize(mat, &m, NULL));
3086:   PetscCall(PetscMalloc1(m + 1, &rowidxs));
3087:   PetscCall(PetscViewerBinaryReadAll(viewer, rowidxs + 1, m, PETSC_DECIDE, M, PETSC_INT));
3088:   rowidxs[0] = 0;
3089:   for (i = 0; i < m; i++) rowidxs[i + 1] += rowidxs[i];
3090:   if (nz != PETSC_INT_MAX) {
3091:     PetscCallMPI(MPIU_Allreduce(&rowidxs[m], &sum, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)viewer)));
3092:     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);
3093:   }

3095:   /* read in column indices and matrix values */
3096:   PetscCall(PetscMalloc2(rowidxs[m], &colidxs, rowidxs[m], &matvals));
3097:   PetscCall(PetscViewerBinaryReadAll(viewer, colidxs, rowidxs[m], PETSC_DETERMINE, PETSC_DETERMINE, PETSC_INT));
3098:   PetscCall(PetscViewerBinaryReadAll(viewer, matvals, rowidxs[m], PETSC_DETERMINE, PETSC_DETERMINE, PETSC_SCALAR));
3099:   /* store matrix indices and values */
3100:   PetscCall(MatMPIAIJSetPreallocationCSR(mat, rowidxs, colidxs, matvals));
3101:   PetscCall(PetscFree(rowidxs));
3102:   PetscCall(PetscFree2(colidxs, matvals));
3103:   PetscFunctionReturn(PETSC_SUCCESS);
3104: }

3106: /* Not scalable because of ISAllGather() unless getting all columns. */
3107: static PetscErrorCode ISGetSeqIS_Private(Mat mat, IS iscol, IS *isseq)
3108: {
3109:   IS          iscol_local;
3110:   PetscBool   isstride;
3111:   PetscMPIInt gisstride = 0;

3113:   PetscFunctionBegin;
3114:   /* check if we are grabbing all columns*/
3115:   PetscCall(PetscObjectTypeCompare((PetscObject)iscol, ISSTRIDE, &isstride));

3117:   if (isstride) {
3118:     PetscInt start, len, mstart, mlen;
3119:     PetscCall(ISStrideGetInfo(iscol, &start, NULL));
3120:     PetscCall(ISGetLocalSize(iscol, &len));
3121:     PetscCall(MatGetOwnershipRangeColumn(mat, &mstart, &mlen));
3122:     if (mstart == start && mlen - mstart == len) gisstride = 1;
3123:   }

3125:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &gisstride, 1, MPI_INT, MPI_MIN, PetscObjectComm((PetscObject)mat)));
3126:   if (gisstride) {
3127:     PetscInt N;
3128:     PetscCall(MatGetSize(mat, NULL, &N));
3129:     PetscCall(ISCreateStride(PETSC_COMM_SELF, N, 0, 1, &iscol_local));
3130:     PetscCall(ISSetIdentity(iscol_local));
3131:     PetscCall(PetscInfo(mat, "Optimizing for obtaining all columns of the matrix; skipping ISAllGather()\n"));
3132:   } else {
3133:     PetscInt cbs;
3134:     PetscCall(ISGetBlockSize(iscol, &cbs));
3135:     PetscCall(ISAllGather(iscol, &iscol_local));
3136:     PetscCall(ISSetBlockSize(iscol_local, cbs));
3137:   }

3139:   *isseq = iscol_local;
3140:   PetscFunctionReturn(PETSC_SUCCESS);
3141: }

3143: /*
3144:  Used by MatCreateSubMatrix_MPIAIJ_SameRowColDist() to avoid ISAllGather() and global size of iscol_local
3145:  (see MatCreateSubMatrix_MPIAIJ_nonscalable)

3147:  Input Parameters:
3148: +   mat - matrix
3149: .   isrow - parallel row index set; its local indices are a subset of local columns of `mat`,
3150:            i.e., mat->rstart <= isrow[i] < mat->rend
3151: -   iscol - parallel column index set; its local indices are a subset of local columns of `mat`,
3152:            i.e., mat->cstart <= iscol[i] < mat->cend

3154:  Output Parameters:
3155: +   isrow_d - sequential row index set for retrieving mat->A
3156: .   iscol_d - sequential  column index set for retrieving mat->A
3157: .   iscol_o - sequential column index set for retrieving mat->B
3158: -   garray - column map; garray[i] indicates global location of iscol_o[i] in `iscol`
3159:  */
3160: static PetscErrorCode ISGetSeqIS_SameColDist_Private(Mat mat, IS isrow, IS iscol, IS *isrow_d, IS *iscol_d, IS *iscol_o, PetscInt *garray[])
3161: {
3162:   Vec             x, cmap;
3163:   const PetscInt *is_idx;
3164:   PetscScalar    *xarray, *cmaparray;
3165:   PetscInt        ncols, isstart, *idx, m, rstart, *cmap1, count;
3166:   Mat_MPIAIJ     *a    = (Mat_MPIAIJ *)mat->data;
3167:   Mat             B    = a->B;
3168:   Vec             lvec = a->lvec, lcmap;
3169:   PetscInt        i, cstart, cend, Bn = B->cmap->N;
3170:   MPI_Comm        comm;
3171:   VecScatter      Mvctx = a->Mvctx;

3173:   PetscFunctionBegin;
3174:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3175:   PetscCall(ISGetLocalSize(iscol, &ncols));

3177:   /* (1) iscol is a sub-column vector of mat, pad it with '-1.' to form a full vector x */
3178:   PetscCall(MatCreateVecs(mat, &x, NULL));
3179:   PetscCall(VecSet(x, -1.0));
3180:   PetscCall(VecDuplicate(x, &cmap));
3181:   PetscCall(VecSet(cmap, -1.0));

3183:   /* Get start indices */
3184:   PetscCallMPI(MPI_Scan(&ncols, &isstart, 1, MPIU_INT, MPI_SUM, comm));
3185:   isstart -= ncols;
3186:   PetscCall(MatGetOwnershipRangeColumn(mat, &cstart, &cend));

3188:   PetscCall(ISGetIndices(iscol, &is_idx));
3189:   PetscCall(VecGetArray(x, &xarray));
3190:   PetscCall(VecGetArray(cmap, &cmaparray));
3191:   PetscCall(PetscMalloc1(ncols, &idx));
3192:   for (i = 0; i < ncols; i++) {
3193:     xarray[is_idx[i] - cstart]    = (PetscScalar)is_idx[i];
3194:     cmaparray[is_idx[i] - cstart] = i + isstart;        /* global index of iscol[i] */
3195:     idx[i]                        = is_idx[i] - cstart; /* local index of iscol[i]  */
3196:   }
3197:   PetscCall(VecRestoreArray(x, &xarray));
3198:   PetscCall(VecRestoreArray(cmap, &cmaparray));
3199:   PetscCall(ISRestoreIndices(iscol, &is_idx));

3201:   /* Get iscol_d */
3202:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, iscol_d));
3203:   PetscCall(ISGetBlockSize(iscol, &i));
3204:   PetscCall(ISSetBlockSize(*iscol_d, i));

3206:   /* Get isrow_d */
3207:   PetscCall(ISGetLocalSize(isrow, &m));
3208:   rstart = mat->rmap->rstart;
3209:   PetscCall(PetscMalloc1(m, &idx));
3210:   PetscCall(ISGetIndices(isrow, &is_idx));
3211:   for (i = 0; i < m; i++) idx[i] = is_idx[i] - rstart;
3212:   PetscCall(ISRestoreIndices(isrow, &is_idx));

3214:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, m, idx, PETSC_OWN_POINTER, isrow_d));
3215:   PetscCall(ISGetBlockSize(isrow, &i));
3216:   PetscCall(ISSetBlockSize(*isrow_d, i));

3218:   /* (2) Scatter x and cmap using aij->Mvctx to get their off-process portions (see MatMult_MPIAIJ) */
3219:   PetscCall(VecScatterBegin(Mvctx, x, lvec, INSERT_VALUES, SCATTER_FORWARD));
3220:   PetscCall(VecScatterEnd(Mvctx, x, lvec, INSERT_VALUES, SCATTER_FORWARD));

3222:   PetscCall(VecDuplicate(lvec, &lcmap));

3224:   PetscCall(VecScatterBegin(Mvctx, cmap, lcmap, INSERT_VALUES, SCATTER_FORWARD));
3225:   PetscCall(VecScatterEnd(Mvctx, cmap, lcmap, INSERT_VALUES, SCATTER_FORWARD));

3227:   /* (3) create sequential iscol_o (a subset of iscol) and isgarray */
3228:   /* off-process column indices */
3229:   count = 0;
3230:   PetscCall(PetscMalloc1(Bn, &idx));
3231:   PetscCall(PetscMalloc1(Bn, &cmap1));

3233:   PetscCall(VecGetArray(lvec, &xarray));
3234:   PetscCall(VecGetArray(lcmap, &cmaparray));
3235:   for (i = 0; i < Bn; i++) {
3236:     if (PetscRealPart(xarray[i]) > -1.0) {
3237:       idx[count]   = i;                                     /* local column index in off-diagonal part B */
3238:       cmap1[count] = (PetscInt)PetscRealPart(cmaparray[i]); /* column index in submat */
3239:       count++;
3240:     }
3241:   }
3242:   PetscCall(VecRestoreArray(lvec, &xarray));
3243:   PetscCall(VecRestoreArray(lcmap, &cmaparray));

3245:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count, idx, PETSC_COPY_VALUES, iscol_o));
3246:   /* cannot ensure iscol_o has same blocksize as iscol! */

3248:   PetscCall(PetscFree(idx));
3249:   *garray = cmap1;

3251:   PetscCall(VecDestroy(&x));
3252:   PetscCall(VecDestroy(&cmap));
3253:   PetscCall(VecDestroy(&lcmap));
3254:   PetscFunctionReturn(PETSC_SUCCESS);
3255: }

3257: /* isrow and iscol have same processor distribution as mat, output *submat is a submatrix of local mat */
3258: PetscErrorCode MatCreateSubMatrix_MPIAIJ_SameRowColDist(Mat mat, IS isrow, IS iscol, MatReuse call, Mat *submat)
3259: {
3260:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)mat->data, *asub;
3261:   Mat         M = NULL;
3262:   MPI_Comm    comm;
3263:   IS          iscol_d, isrow_d, iscol_o;
3264:   Mat         Asub = NULL, Bsub = NULL;
3265:   PetscInt    n, count, M_size, N_size;

3267:   PetscFunctionBegin;
3268:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));

3270:   if (call == MAT_REUSE_MATRIX) {
3271:     /* Retrieve isrow_d, iscol_d and iscol_o from submat */
3272:     PetscCall(PetscObjectQuery((PetscObject)*submat, "isrow_d", (PetscObject *)&isrow_d));
3273:     PetscCheck(isrow_d, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "isrow_d passed in was not used before, cannot reuse");

3275:     PetscCall(PetscObjectQuery((PetscObject)*submat, "iscol_d", (PetscObject *)&iscol_d));
3276:     PetscCheck(iscol_d, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "iscol_d passed in was not used before, cannot reuse");

3278:     PetscCall(PetscObjectQuery((PetscObject)*submat, "iscol_o", (PetscObject *)&iscol_o));
3279:     PetscCheck(iscol_o, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "iscol_o passed in was not used before, cannot reuse");

3281:     /* Update diagonal and off-diagonal portions of submat */
3282:     asub = (Mat_MPIAIJ *)(*submat)->data;
3283:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->A, isrow_d, iscol_d, PETSC_DECIDE, MAT_REUSE_MATRIX, &asub->A));
3284:     PetscCall(ISGetLocalSize(iscol_o, &n));
3285:     if (n) PetscCall(MatCreateSubMatrix_SeqAIJ(a->B, isrow_d, iscol_o, PETSC_DECIDE, MAT_REUSE_MATRIX, &asub->B));
3286:     PetscCall(MatAssemblyBegin(*submat, MAT_FINAL_ASSEMBLY));
3287:     PetscCall(MatAssemblyEnd(*submat, MAT_FINAL_ASSEMBLY));

3289:   } else { /* call == MAT_INITIAL_MATRIX) */
3290:     PetscInt *garray, *garray_compact;
3291:     PetscInt  BsubN;

3293:     /* Create isrow_d, iscol_d, iscol_o and isgarray (replace isgarray with array?) */
3294:     PetscCall(ISGetSeqIS_SameColDist_Private(mat, isrow, iscol, &isrow_d, &iscol_d, &iscol_o, &garray));

3296:     /* Create local submatrices Asub and Bsub */
3297:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->A, isrow_d, iscol_d, PETSC_DECIDE, MAT_INITIAL_MATRIX, &Asub));
3298:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->B, isrow_d, iscol_o, PETSC_DECIDE, MAT_INITIAL_MATRIX, &Bsub));

3300:     // Compact garray so its not of size Bn
3301:     PetscCall(ISGetSize(iscol_o, &count));
3302:     PetscCall(PetscMalloc1(count, &garray_compact));
3303:     PetscCall(PetscArraycpy(garray_compact, garray, count));

3305:     /* Create submatrix M */
3306:     PetscCall(ISGetSize(isrow, &M_size));
3307:     PetscCall(ISGetSize(iscol, &N_size));
3308:     PetscCall(MatCreateMPIAIJWithSeqAIJ(comm, M_size, N_size, Asub, Bsub, garray_compact, &M));

3310:     /* If Bsub has empty columns, compress iscol_o such that it will retrieve condensed Bsub from a->B during reuse */
3311:     asub = (Mat_MPIAIJ *)M->data;

3313:     PetscCall(ISGetLocalSize(iscol_o, &BsubN));
3314:     n = asub->B->cmap->N;
3315:     if (BsubN > n) {
3316:       /* This case can be tested using ~petsc/src/tao/bound/tutorials/runplate2_3 */
3317:       const PetscInt *idx;
3318:       PetscInt        i, j, *idx_new, *subgarray = asub->garray;
3319:       PetscCall(PetscInfo(M, "submatrix Bn %" PetscInt_FMT " != BsubN %" PetscInt_FMT ", update iscol_o\n", n, BsubN));

3321:       PetscCall(PetscMalloc1(n, &idx_new));
3322:       j = 0;
3323:       PetscCall(ISGetIndices(iscol_o, &idx));
3324:       for (i = 0; i < n; i++) {
3325:         if (j >= BsubN) break;
3326:         while (subgarray[i] > garray[j]) j++;

3328:         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]);
3329:         idx_new[i] = idx[j++];
3330:       }
3331:       PetscCall(ISRestoreIndices(iscol_o, &idx));

3333:       PetscCall(ISDestroy(&iscol_o));
3334:       PetscCall(ISCreateGeneral(PETSC_COMM_SELF, n, idx_new, PETSC_OWN_POINTER, &iscol_o));

3336:     } 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);

3338:     PetscCall(PetscFree(garray));
3339:     *submat = M;

3341:     /* Save isrow_d, iscol_d and iscol_o used in processor for next request */
3342:     PetscCall(PetscObjectCompose((PetscObject)M, "isrow_d", (PetscObject)isrow_d));
3343:     PetscCall(ISDestroy(&isrow_d));

3345:     PetscCall(PetscObjectCompose((PetscObject)M, "iscol_d", (PetscObject)iscol_d));
3346:     PetscCall(ISDestroy(&iscol_d));

3348:     PetscCall(PetscObjectCompose((PetscObject)M, "iscol_o", (PetscObject)iscol_o));
3349:     PetscCall(ISDestroy(&iscol_o));
3350:   }
3351:   PetscFunctionReturn(PETSC_SUCCESS);
3352: }

3354: PetscErrorCode MatCreateSubMatrix_MPIAIJ(Mat mat, IS isrow, IS iscol, MatReuse call, Mat *newmat)
3355: {
3356:   IS        iscol_local = NULL, isrow_d;
3357:   PetscInt  csize;
3358:   PetscInt  n, i, j, start, end;
3359:   PetscBool sameRowDist = PETSC_FALSE, sameDist[2], tsameDist[2];
3360:   MPI_Comm  comm;

3362:   PetscFunctionBegin;
3363:   /* If isrow has same processor distribution as mat,
3364:      call MatCreateSubMatrix_MPIAIJ_SameRowDist() to avoid using a hash table with global size of iscol */
3365:   if (call == MAT_REUSE_MATRIX) {
3366:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "isrow_d", (PetscObject *)&isrow_d));
3367:     if (isrow_d) {
3368:       sameRowDist  = PETSC_TRUE;
3369:       tsameDist[1] = PETSC_TRUE; /* sameColDist */
3370:     } else {
3371:       PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_local));
3372:       if (iscol_local) {
3373:         sameRowDist  = PETSC_TRUE;
3374:         tsameDist[1] = PETSC_FALSE; /* !sameColDist */
3375:       }
3376:     }
3377:   } else {
3378:     /* Check if isrow has same processor distribution as mat */
3379:     sameDist[0] = PETSC_FALSE;
3380:     PetscCall(ISGetLocalSize(isrow, &n));
3381:     if (!n) {
3382:       sameDist[0] = PETSC_TRUE;
3383:     } else {
3384:       PetscCall(ISGetMinMax(isrow, &i, &j));
3385:       PetscCall(MatGetOwnershipRange(mat, &start, &end));
3386:       if (i >= start && j < end) sameDist[0] = PETSC_TRUE;
3387:     }

3389:     /* Check if iscol has same processor distribution as mat */
3390:     sameDist[1] = PETSC_FALSE;
3391:     PetscCall(ISGetLocalSize(iscol, &n));
3392:     if (!n) {
3393:       sameDist[1] = PETSC_TRUE;
3394:     } else {
3395:       PetscCall(ISGetMinMax(iscol, &i, &j));
3396:       PetscCall(MatGetOwnershipRangeColumn(mat, &start, &end));
3397:       if (i >= start && j < end) sameDist[1] = PETSC_TRUE;
3398:     }

3400:     PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3401:     PetscCallMPI(MPIU_Allreduce(&sameDist, &tsameDist, 2, MPIU_BOOL, MPI_LAND, comm));
3402:     sameRowDist = tsameDist[0];
3403:   }

3405:   if (sameRowDist) {
3406:     if (tsameDist[1]) { /* sameRowDist & sameColDist */
3407:       /* isrow and iscol have same processor distribution as mat */
3408:       PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowColDist(mat, isrow, iscol, call, newmat));
3409:       PetscFunctionReturn(PETSC_SUCCESS);
3410:     } else { /* sameRowDist */
3411:       /* isrow has same processor distribution as mat */
3412:       if (call == MAT_INITIAL_MATRIX) {
3413:         PetscBool sorted;
3414:         PetscCall(ISGetSeqIS_Private(mat, iscol, &iscol_local));
3415:         PetscCall(ISGetLocalSize(iscol_local, &n)); /* local size of iscol_local = global columns of newmat */
3416:         PetscCall(ISGetSize(iscol, &i));
3417:         PetscCheck(n == i, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "n %" PetscInt_FMT " != size of iscol %" PetscInt_FMT, n, i);

3419:         PetscCall(ISSorted(iscol_local, &sorted));
3420:         if (sorted) {
3421:           /* MatCreateSubMatrix_MPIAIJ_SameRowDist() requires iscol_local be sorted; it can have duplicate indices */
3422:           PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowDist(mat, isrow, iscol, iscol_local, MAT_INITIAL_MATRIX, newmat));
3423:           PetscFunctionReturn(PETSC_SUCCESS);
3424:         }
3425:       } else { /* call == MAT_REUSE_MATRIX */
3426:         IS iscol_sub;
3427:         PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_sub));
3428:         if (iscol_sub) {
3429:           PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowDist(mat, isrow, iscol, NULL, call, newmat));
3430:           PetscFunctionReturn(PETSC_SUCCESS);
3431:         }
3432:       }
3433:     }
3434:   }

3436:   /* General case: iscol -> iscol_local which has global size of iscol */
3437:   if (call == MAT_REUSE_MATRIX) {
3438:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "ISAllGather", (PetscObject *)&iscol_local));
3439:     PetscCheck(iscol_local, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");
3440:   } else {
3441:     if (!iscol_local) PetscCall(ISGetSeqIS_Private(mat, iscol, &iscol_local));
3442:   }

3444:   PetscCall(ISGetLocalSize(iscol, &csize));
3445:   PetscCall(MatCreateSubMatrix_MPIAIJ_nonscalable(mat, isrow, iscol_local, csize, call, newmat));

3447:   if (call == MAT_INITIAL_MATRIX) {
3448:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "ISAllGather", (PetscObject)iscol_local));
3449:     PetscCall(ISDestroy(&iscol_local));
3450:   }
3451:   PetscFunctionReturn(PETSC_SUCCESS);
3452: }

3454: /*@C
3455:   MatCreateMPIAIJWithSeqAIJ - creates a `MATMPIAIJ` matrix using `MATSEQAIJ` matrices that contain the "diagonal"
3456:   and "off-diagonal" part of the matrix in CSR format.

3458:   Collective

3460:   Input Parameters:
3461: + comm   - MPI communicator
3462: . M      - the global row size
3463: . N      - the global column size
3464: . A      - "diagonal" portion of matrix
3465: . 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
3466: - 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.

3468:   Output Parameter:
3469: . mat - the matrix, with input `A` as its local diagonal matrix

3471:   Level: advanced

3473:   Notes:
3474:   See `MatCreateAIJ()` for the definition of "diagonal" and "off-diagonal" portion of the matrix.

3476:   `A` and `B` becomes part of output mat. The user cannot use `A` and `B` anymore.

3478:   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
3479:   `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
3480:   `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`
3481:   yourself, see algorithms in the private function `MatSetUpMultiply_MPIAIJ()`.

3483:   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.

3485: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateMPIAIJWithSplitArrays()`
3486: @*/
3487: PetscErrorCode MatCreateMPIAIJWithSeqAIJ(MPI_Comm comm, PetscInt M, PetscInt N, Mat A, Mat B, PetscInt *garray, Mat *mat)
3488: {
3489:   PetscInt    m, n;
3490:   MatType     mpi_mat_type;
3491:   Mat_MPIAIJ *mpiaij;
3492:   Mat         C;

3494:   PetscFunctionBegin;
3495:   PetscCall(MatCreate(comm, &C));
3496:   PetscCall(MatGetSize(A, &m, &n));
3497:   PetscCheck(m == B->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Am %" PetscInt_FMT " != Bm %" PetscInt_FMT, m, B->rmap->N);
3498:   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);

3500:   PetscCall(MatSetSizes(C, m, n, M, N));
3501:   /* Determine the type of MPI matrix that should be created from the type of matrix A, which holds the "diagonal" portion. */
3502:   PetscCall(MatGetMPIMatType_Private(A, &mpi_mat_type));
3503:   PetscCall(MatSetType(C, mpi_mat_type));
3504:   if (!garray) {
3505:     const PetscScalar *ba;

3507:     B->nonzerostate++;
3508:     PetscCall(MatSeqAIJGetArrayRead(B, &ba)); /* Since we will destroy B's device copy, we need to make sure the host copy is up to date */
3509:     PetscCall(MatSeqAIJRestoreArrayRead(B, &ba));
3510:   }

3512:   PetscCall(MatSetBlockSizes(C, A->rmap->bs, A->cmap->bs));
3513:   PetscCall(PetscLayoutSetUp(C->rmap));
3514:   PetscCall(PetscLayoutSetUp(C->cmap));

3516:   mpiaij              = (Mat_MPIAIJ *)C->data;
3517:   mpiaij->A           = A;
3518:   mpiaij->B           = B;
3519:   mpiaij->garray      = garray;
3520:   C->preallocated     = PETSC_TRUE;
3521:   C->nooffprocentries = PETSC_TRUE; /* See MatAssemblyBegin_MPIAIJ. In effect, making MatAssemblyBegin a nop */

3523:   PetscCall(MatSetOption(C, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
3524:   PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
3525:   /* MatAssemblyEnd is critical here. It sets mat->offloadmask according to A and B's, and
3526:    also gets mpiaij->B compacted (if garray is NULL), with its col ids and size reduced
3527:    */
3528:   PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
3529:   PetscCall(MatSetOption(C, MAT_NO_OFF_PROC_ENTRIES, PETSC_FALSE));
3530:   PetscCall(MatSetOption(C, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
3531:   *mat = C;
3532:   PetscFunctionReturn(PETSC_SUCCESS);
3533: }

3535: extern PetscErrorCode MatCreateSubMatrices_MPIAIJ_SingleIS_Local(Mat, PetscInt, const IS[], const IS[], MatReuse, PetscBool, Mat *);

3537: PetscErrorCode MatCreateSubMatrix_MPIAIJ_SameRowDist(Mat mat, IS isrow, IS iscol, IS iscol_local, MatReuse call, Mat *newmat)
3538: {
3539:   PetscInt        i, m, n, rstart, row, rend, nz, j, bs, cbs;
3540:   PetscInt       *ii, *jj, nlocal, *dlens, *olens, dlen, olen, jend, mglobal;
3541:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)mat->data;
3542:   Mat             M, Msub, B = a->B;
3543:   MatScalar      *aa;
3544:   Mat_SeqAIJ     *aij;
3545:   PetscInt       *garray = a->garray, *colsub, Ncols;
3546:   PetscInt        count, Bn = B->cmap->N, cstart = mat->cmap->rstart, cend = mat->cmap->rend;
3547:   IS              iscol_sub, iscmap;
3548:   const PetscInt *is_idx, *cmap;
3549:   PetscBool       allcolumns = PETSC_FALSE;
3550:   MPI_Comm        comm;

3552:   PetscFunctionBegin;
3553:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3554:   if (call == MAT_REUSE_MATRIX) {
3555:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_sub));
3556:     PetscCheck(iscol_sub, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "SubIScol passed in was not used before, cannot reuse");
3557:     PetscCall(ISGetLocalSize(iscol_sub, &count));

3559:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "Subcmap", (PetscObject *)&iscmap));
3560:     PetscCheck(iscmap, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Subcmap passed in was not used before, cannot reuse");

3562:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubMatrix", (PetscObject *)&Msub));
3563:     PetscCheck(Msub, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");

3565:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol_sub, MAT_REUSE_MATRIX, PETSC_FALSE, &Msub));

3567:   } else { /* call == MAT_INITIAL_MATRIX) */
3568:     PetscBool flg;

3570:     PetscCall(ISGetLocalSize(iscol, &n));
3571:     PetscCall(ISGetSize(iscol, &Ncols));

3573:     /* (1) iscol -> nonscalable iscol_local */
3574:     /* Check for special case: each processor gets entire matrix columns */
3575:     PetscCall(ISIdentity(iscol_local, &flg));
3576:     if (flg && n == mat->cmap->N) allcolumns = PETSC_TRUE;
3577:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &allcolumns, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));
3578:     if (allcolumns) {
3579:       iscol_sub = iscol_local;
3580:       PetscCall(PetscObjectReference((PetscObject)iscol_local));
3581:       PetscCall(ISCreateStride(PETSC_COMM_SELF, n, 0, 1, &iscmap));

3583:     } else {
3584:       /* (2) iscol_local -> iscol_sub and iscmap. Implementation below requires iscol_local be sorted, it can have duplicate indices */
3585:       PetscInt *idx, *cmap1, k;
3586:       PetscCall(PetscMalloc1(Ncols, &idx));
3587:       PetscCall(PetscMalloc1(Ncols, &cmap1));
3588:       PetscCall(ISGetIndices(iscol_local, &is_idx));
3589:       count = 0;
3590:       k     = 0;
3591:       for (i = 0; i < Ncols; i++) {
3592:         j = is_idx[i];
3593:         if (j >= cstart && j < cend) {
3594:           /* diagonal part of mat */
3595:           idx[count]     = j;
3596:           cmap1[count++] = i; /* column index in submat */
3597:         } else if (Bn) {
3598:           /* off-diagonal part of mat */
3599:           if (j == garray[k]) {
3600:             idx[count]     = j;
3601:             cmap1[count++] = i; /* column index in submat */
3602:           } else if (j > garray[k]) {
3603:             while (j > garray[k] && k < Bn - 1) k++;
3604:             if (j == garray[k]) {
3605:               idx[count]     = j;
3606:               cmap1[count++] = i; /* column index in submat */
3607:             }
3608:           }
3609:         }
3610:       }
3611:       PetscCall(ISRestoreIndices(iscol_local, &is_idx));

3613:       PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count, idx, PETSC_OWN_POINTER, &iscol_sub));
3614:       PetscCall(ISGetBlockSize(iscol, &cbs));
3615:       PetscCall(ISSetBlockSize(iscol_sub, cbs));

3617:       PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)iscol_local), count, cmap1, PETSC_OWN_POINTER, &iscmap));
3618:     }

3620:     /* (3) Create sequential Msub */
3621:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol_sub, MAT_INITIAL_MATRIX, allcolumns, &Msub));
3622:   }

3624:   PetscCall(ISGetLocalSize(iscol_sub, &count));
3625:   aij = (Mat_SeqAIJ *)Msub->data;
3626:   ii  = aij->i;
3627:   PetscCall(ISGetIndices(iscmap, &cmap));

3629:   /*
3630:       m - number of local rows
3631:       Ncols - number of columns (same on all processors)
3632:       rstart - first row in new global matrix generated
3633:   */
3634:   PetscCall(MatGetSize(Msub, &m, NULL));

3636:   if (call == MAT_INITIAL_MATRIX) {
3637:     /* (4) Create parallel newmat */
3638:     PetscMPIInt rank, size;
3639:     PetscInt    csize;

3641:     PetscCallMPI(MPI_Comm_size(comm, &size));
3642:     PetscCallMPI(MPI_Comm_rank(comm, &rank));

3644:     /*
3645:         Determine the number of non-zeros in the diagonal and off-diagonal
3646:         portions of the matrix in order to do correct preallocation
3647:     */

3649:     /* first get start and end of "diagonal" columns */
3650:     PetscCall(ISGetLocalSize(iscol, &csize));
3651:     if (csize == PETSC_DECIDE) {
3652:       PetscCall(ISGetSize(isrow, &mglobal));
3653:       if (mglobal == Ncols) { /* square matrix */
3654:         nlocal = m;
3655:       } else {
3656:         nlocal = Ncols / size + ((Ncols % size) > rank);
3657:       }
3658:     } else {
3659:       nlocal = csize;
3660:     }
3661:     PetscCallMPI(MPI_Scan(&nlocal, &rend, 1, MPIU_INT, MPI_SUM, comm));
3662:     rstart = rend - nlocal;
3663:     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);

3665:     /* next, compute all the lengths */
3666:     jj = aij->j;
3667:     PetscCall(PetscMalloc1(2 * m + 1, &dlens));
3668:     olens = dlens + m;
3669:     for (i = 0; i < m; i++) {
3670:       jend = ii[i + 1] - ii[i];
3671:       olen = 0;
3672:       dlen = 0;
3673:       for (j = 0; j < jend; j++) {
3674:         if (cmap[*jj] < rstart || cmap[*jj] >= rend) olen++;
3675:         else dlen++;
3676:         jj++;
3677:       }
3678:       olens[i] = olen;
3679:       dlens[i] = dlen;
3680:     }

3682:     PetscCall(ISGetBlockSize(isrow, &bs));
3683:     PetscCall(ISGetBlockSize(iscol, &cbs));

3685:     PetscCall(MatCreate(comm, &M));
3686:     PetscCall(MatSetSizes(M, m, nlocal, PETSC_DECIDE, Ncols));
3687:     PetscCall(MatSetBlockSizes(M, bs, cbs));
3688:     PetscCall(MatSetType(M, ((PetscObject)mat)->type_name));
3689:     PetscCall(MatMPIAIJSetPreallocation(M, 0, dlens, 0, olens));
3690:     PetscCall(PetscFree(dlens));

3692:   } else { /* call == MAT_REUSE_MATRIX */
3693:     M = *newmat;
3694:     PetscCall(MatGetLocalSize(M, &i, NULL));
3695:     PetscCheck(i == m, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Previous matrix must be same size/layout as request");
3696:     PetscCall(MatZeroEntries(M));
3697:     /*
3698:          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3699:        rather than the slower MatSetValues().
3700:     */
3701:     M->was_assembled = PETSC_TRUE;
3702:     M->assembled     = PETSC_FALSE;
3703:   }

3705:   /* (5) Set values of Msub to *newmat */
3706:   PetscCall(PetscMalloc1(count, &colsub));
3707:   PetscCall(MatGetOwnershipRange(M, &rstart, NULL));

3709:   jj = aij->j;
3710:   PetscCall(MatSeqAIJGetArrayRead(Msub, (const PetscScalar **)&aa));
3711:   for (i = 0; i < m; i++) {
3712:     row = rstart + i;
3713:     nz  = ii[i + 1] - ii[i];
3714:     for (j = 0; j < nz; j++) colsub[j] = cmap[jj[j]];
3715:     PetscCall(MatSetValues_MPIAIJ(M, 1, &row, nz, colsub, aa, INSERT_VALUES));
3716:     jj += nz;
3717:     aa += nz;
3718:   }
3719:   PetscCall(MatSeqAIJRestoreArrayRead(Msub, (const PetscScalar **)&aa));
3720:   PetscCall(ISRestoreIndices(iscmap, &cmap));

3722:   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
3723:   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));

3725:   PetscCall(PetscFree(colsub));

3727:   /* save Msub, iscol_sub and iscmap used in processor for next request */
3728:   if (call == MAT_INITIAL_MATRIX) {
3729:     *newmat = M;
3730:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "SubMatrix", (PetscObject)Msub));
3731:     PetscCall(MatDestroy(&Msub));

3733:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "SubIScol", (PetscObject)iscol_sub));
3734:     PetscCall(ISDestroy(&iscol_sub));

3736:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "Subcmap", (PetscObject)iscmap));
3737:     PetscCall(ISDestroy(&iscmap));

3739:     if (iscol_local) {
3740:       PetscCall(PetscObjectCompose((PetscObject)*newmat, "ISAllGather", (PetscObject)iscol_local));
3741:       PetscCall(ISDestroy(&iscol_local));
3742:     }
3743:   }
3744:   PetscFunctionReturn(PETSC_SUCCESS);
3745: }

3747: /*
3748:     Not great since it makes two copies of the submatrix, first an SeqAIJ
3749:   in local and then by concatenating the local matrices the end result.
3750:   Writing it directly would be much like MatCreateSubMatrices_MPIAIJ()

3752:   This requires a sequential iscol with all indices.
3753: */
3754: PetscErrorCode MatCreateSubMatrix_MPIAIJ_nonscalable(Mat mat, IS isrow, IS iscol, PetscInt csize, MatReuse call, Mat *newmat)
3755: {
3756:   PetscMPIInt rank, size;
3757:   PetscInt    i, m, n, rstart, row, rend, nz, *cwork, j, bs, cbs;
3758:   PetscInt   *ii, *jj, nlocal, *dlens, *olens, dlen, olen, jend, mglobal;
3759:   Mat         M, Mreuse;
3760:   MatScalar  *aa, *vwork;
3761:   MPI_Comm    comm;
3762:   Mat_SeqAIJ *aij;
3763:   PetscBool   colflag, allcolumns = PETSC_FALSE;

3765:   PetscFunctionBegin;
3766:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3767:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
3768:   PetscCallMPI(MPI_Comm_size(comm, &size));

3770:   /* Check for special case: each processor gets entire matrix columns */
3771:   PetscCall(ISIdentity(iscol, &colflag));
3772:   PetscCall(ISGetLocalSize(iscol, &n));
3773:   if (colflag && n == mat->cmap->N) allcolumns = PETSC_TRUE;
3774:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &allcolumns, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));

3776:   if (call == MAT_REUSE_MATRIX) {
3777:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubMatrix", (PetscObject *)&Mreuse));
3778:     PetscCheck(Mreuse, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");
3779:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol, MAT_REUSE_MATRIX, allcolumns, &Mreuse));
3780:   } else {
3781:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol, MAT_INITIAL_MATRIX, allcolumns, &Mreuse));
3782:   }

3784:   /*
3785:       m - number of local rows
3786:       n - number of columns (same on all processors)
3787:       rstart - first row in new global matrix generated
3788:   */
3789:   PetscCall(MatGetSize(Mreuse, &m, &n));
3790:   PetscCall(MatGetBlockSizes(Mreuse, &bs, &cbs));
3791:   if (call == MAT_INITIAL_MATRIX) {
3792:     aij = (Mat_SeqAIJ *)Mreuse->data;
3793:     ii  = aij->i;
3794:     jj  = aij->j;

3796:     /*
3797:         Determine the number of non-zeros in the diagonal and off-diagonal
3798:         portions of the matrix in order to do correct preallocation
3799:     */

3801:     /* first get start and end of "diagonal" columns */
3802:     if (csize == PETSC_DECIDE) {
3803:       PetscCall(ISGetSize(isrow, &mglobal));
3804:       if (mglobal == n) { /* square matrix */
3805:         nlocal = m;
3806:       } else {
3807:         nlocal = n / size + ((n % size) > rank);
3808:       }
3809:     } else {
3810:       nlocal = csize;
3811:     }
3812:     PetscCallMPI(MPI_Scan(&nlocal, &rend, 1, MPIU_INT, MPI_SUM, comm));
3813:     rstart = rend - nlocal;
3814:     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);

3816:     /* next, compute all the lengths */
3817:     PetscCall(PetscMalloc1(2 * m + 1, &dlens));
3818:     olens = dlens + m;
3819:     for (i = 0; i < m; i++) {
3820:       jend = ii[i + 1] - ii[i];
3821:       olen = 0;
3822:       dlen = 0;
3823:       for (j = 0; j < jend; j++) {
3824:         if (*jj < rstart || *jj >= rend) olen++;
3825:         else dlen++;
3826:         jj++;
3827:       }
3828:       olens[i] = olen;
3829:       dlens[i] = dlen;
3830:     }
3831:     PetscCall(MatCreate(comm, &M));
3832:     PetscCall(MatSetSizes(M, m, nlocal, PETSC_DECIDE, n));
3833:     PetscCall(MatSetBlockSizes(M, bs, cbs));
3834:     PetscCall(MatSetType(M, ((PetscObject)mat)->type_name));
3835:     PetscCall(MatMPIAIJSetPreallocation(M, 0, dlens, 0, olens));
3836:     PetscCall(PetscFree(dlens));
3837:   } else {
3838:     PetscInt ml, nl;

3840:     M = *newmat;
3841:     PetscCall(MatGetLocalSize(M, &ml, &nl));
3842:     PetscCheck(ml == m, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Previous matrix must be same size/layout as request");
3843:     PetscCall(MatZeroEntries(M));
3844:     /*
3845:          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3846:        rather than the slower MatSetValues().
3847:     */
3848:     M->was_assembled = PETSC_TRUE;
3849:     M->assembled     = PETSC_FALSE;
3850:   }
3851:   PetscCall(MatGetOwnershipRange(M, &rstart, &rend));
3852:   aij = (Mat_SeqAIJ *)Mreuse->data;
3853:   ii  = aij->i;
3854:   jj  = aij->j;

3856:   /* trigger copy to CPU if needed */
3857:   PetscCall(MatSeqAIJGetArrayRead(Mreuse, (const PetscScalar **)&aa));
3858:   for (i = 0; i < m; i++) {
3859:     row   = rstart + i;
3860:     nz    = ii[i + 1] - ii[i];
3861:     cwork = jj;
3862:     jj    = PetscSafePointerPlusOffset(jj, nz);
3863:     vwork = aa;
3864:     aa    = PetscSafePointerPlusOffset(aa, nz);
3865:     PetscCall(MatSetValues_MPIAIJ(M, 1, &row, nz, cwork, vwork, INSERT_VALUES));
3866:   }
3867:   PetscCall(MatSeqAIJRestoreArrayRead(Mreuse, (const PetscScalar **)&aa));

3869:   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
3870:   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));
3871:   *newmat = M;

3873:   /* save submatrix used in processor for next request */
3874:   if (call == MAT_INITIAL_MATRIX) {
3875:     PetscCall(PetscObjectCompose((PetscObject)M, "SubMatrix", (PetscObject)Mreuse));
3876:     PetscCall(MatDestroy(&Mreuse));
3877:   }
3878:   PetscFunctionReturn(PETSC_SUCCESS);
3879: }

3881: static PetscErrorCode MatMPIAIJSetPreallocationCSR_MPIAIJ(Mat B, const PetscInt Ii[], const PetscInt J[], const PetscScalar v[])
3882: {
3883:   PetscInt        m, cstart, cend, j, nnz, i, d, *ld;
3884:   PetscInt       *d_nnz, *o_nnz, nnz_max = 0, rstart, ii, irstart;
3885:   const PetscInt *JJ;
3886:   PetscBool       nooffprocentries;
3887:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)B->data;

3889:   PetscFunctionBegin;
3890:   PetscCall(PetscLayoutSetUp(B->rmap));
3891:   PetscCall(PetscLayoutSetUp(B->cmap));
3892:   m       = B->rmap->n;
3893:   cstart  = B->cmap->rstart;
3894:   cend    = B->cmap->rend;
3895:   rstart  = B->rmap->rstart;
3896:   irstart = Ii[0];

3898:   PetscCall(PetscCalloc2(m, &d_nnz, m, &o_nnz));

3900:   if (PetscDefined(USE_DEBUG)) {
3901:     for (i = 0; i < m; i++) {
3902:       nnz = Ii[i + 1] - Ii[i];
3903:       JJ  = PetscSafePointerPlusOffset(J, Ii[i] - irstart);
3904:       PetscCheck(nnz >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Local row %" PetscInt_FMT " has a negative %" PetscInt_FMT " number of columns", i, nnz);
3905:       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]);
3906:       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);
3907:     }
3908:   }

3910:   for (i = 0; i < m; i++) {
3911:     nnz     = Ii[i + 1] - Ii[i];
3912:     JJ      = PetscSafePointerPlusOffset(J, Ii[i] - irstart);
3913:     nnz_max = PetscMax(nnz_max, nnz);
3914:     d       = 0;
3915:     for (j = 0; j < nnz; j++) {
3916:       if (cstart <= JJ[j] && JJ[j] < cend) d++;
3917:     }
3918:     d_nnz[i] = d;
3919:     o_nnz[i] = nnz - d;
3920:   }
3921:   PetscCall(MatMPIAIJSetPreallocation(B, 0, d_nnz, 0, o_nnz));
3922:   PetscCall(PetscFree2(d_nnz, o_nnz));

3924:   for (i = 0; i < m; i++) {
3925:     ii = i + rstart;
3926:     PetscCall(MatSetValues_MPIAIJ(B, 1, &ii, Ii[i + 1] - Ii[i], PetscSafePointerPlusOffset(J, Ii[i] - irstart), PetscSafePointerPlusOffset(v, Ii[i] - irstart), INSERT_VALUES));
3927:   }
3928:   nooffprocentries    = B->nooffprocentries;
3929:   B->nooffprocentries = PETSC_TRUE;
3930:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
3931:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
3932:   B->nooffprocentries = nooffprocentries;

3934:   /* count number of entries below block diagonal */
3935:   PetscCall(PetscFree(Aij->ld));
3936:   PetscCall(PetscCalloc1(m, &ld));
3937:   Aij->ld = ld;
3938:   for (i = 0; i < m; i++) {
3939:     nnz = Ii[i + 1] - Ii[i];
3940:     j   = 0;
3941:     while (j < nnz && J[j] < cstart) j++;
3942:     ld[i] = j;
3943:     if (J) J += nnz;
3944:   }

3946:   PetscCall(MatSetOption(B, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
3947:   PetscFunctionReturn(PETSC_SUCCESS);
3948: }

3950: /*@
3951:   MatMPIAIJSetPreallocationCSR - Allocates memory for a sparse parallel matrix in `MATAIJ` format
3952:   (the default parallel PETSc format).

3954:   Collective

3956:   Input Parameters:
3957: + B - the matrix
3958: . i - the indices into `j` for the start of each local row (indices start with zero)
3959: . j - the column indices for each local row (indices start with zero)
3960: - v - optional values in the matrix

3962:   Level: developer

3964:   Notes:
3965:   The `i`, `j`, and `v` arrays ARE copied by this routine into the internal format used by PETSc;
3966:   thus you CANNOT change the matrix entries by changing the values of `v` after you have
3967:   called this routine. Use `MatCreateMPIAIJWithSplitArrays()` to avoid needing to copy the arrays.

3969:   The `i` and `j` indices are 0 based, and `i` indices are indices corresponding to the local `j` array.

3971:   A convenience routine for this functionality is `MatCreateMPIAIJWithArrays()`.

3973:   You can update the matrix with new numerical values using `MatUpdateMPIAIJWithArrays()` after this call if the column indices in `j` are sorted.

3975:   If you do **not** use `MatUpdateMPIAIJWithArrays()`, the column indices in `j` do not need to be sorted. If you will use
3976:   `MatUpdateMPIAIJWithArrays()`, the column indices **must** be sorted.

3978:   The format which is used for the sparse matrix input, is equivalent to a
3979:   row-major ordering.. i.e for the following matrix, the input data expected is
3980:   as shown
3981: .vb
3982:         1 0 0
3983:         2 0 3     P0
3984:        -------
3985:         4 5 6     P1

3987:      Process0 [P0] rows_owned=[0,1]
3988:         i =  {0,1,3}  [size = nrow+1  = 2+1]
3989:         j =  {0,0,2}  [size = 3]
3990:         v =  {1,2,3}  [size = 3]

3992:      Process1 [P1] rows_owned=[2]
3993:         i =  {0,3}    [size = nrow+1  = 1+1]
3994:         j =  {0,1,2}  [size = 3]
3995:         v =  {4,5,6}  [size = 3]
3996: .ve

3998: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatCreateAIJ()`,
3999:           `MatCreateSeqAIJWithArrays()`, `MatCreateMPIAIJWithSplitArrays()`, `MatCreateMPIAIJWithArrays()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4000: @*/
4001: PetscErrorCode MatMPIAIJSetPreallocationCSR(Mat B, const PetscInt i[], const PetscInt j[], const PetscScalar v[])
4002: {
4003:   PetscFunctionBegin;
4004:   PetscTryMethod(B, "MatMPIAIJSetPreallocationCSR_C", (Mat, const PetscInt[], const PetscInt[], const PetscScalar[]), (B, i, j, v));
4005:   PetscFunctionReturn(PETSC_SUCCESS);
4006: }

4008: /*@
4009:   MatMPIAIJSetPreallocation - Preallocates memory for a sparse parallel matrix in `MATMPIAIJ` format
4010:   (the default parallel PETSc format).  For good matrix assembly performance
4011:   the user should preallocate the matrix storage by setting the parameters
4012:   `d_nz` (or `d_nnz`) and `o_nz` (or `o_nnz`).

4014:   Collective

4016:   Input Parameters:
4017: + B     - the matrix
4018: . d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4019:            (same value is used for all local rows)
4020: . d_nnz - array containing the number of nonzeros in the various rows of the
4021:            DIAGONAL portion of the local submatrix (possibly different for each row)
4022:            or `NULL` (`PETSC_NULL_INTEGER` in Fortran), if `d_nz` is used to specify the nonzero structure.
4023:            The size of this array is equal to the number of local rows, i.e 'm'.
4024:            For matrices that will be factored, you must leave room for (and set)
4025:            the diagonal entry even if it is zero.
4026: . o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4027:            submatrix (same value is used for all local rows).
4028: - o_nnz - array containing the number of nonzeros in the various rows of the
4029:            OFF-DIAGONAL portion of the local submatrix (possibly different for
4030:            each row) or `NULL` (`PETSC_NULL_INTEGER` in Fortran), if `o_nz` is used to specify the nonzero
4031:            structure. The size of this array is equal to the number
4032:            of local rows, i.e 'm'.

4034:   Example Usage:
4035:   Consider the following 8x8 matrix with 34 non-zero values, that is
4036:   assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4037:   proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4038:   as follows

4040: .vb
4041:             1  2  0  |  0  3  0  |  0  4
4042:     Proc0   0  5  6  |  7  0  0  |  8  0
4043:             9  0 10  | 11  0  0  | 12  0
4044:     -------------------------------------
4045:            13  0 14  | 15 16 17  |  0  0
4046:     Proc1   0 18  0  | 19 20 21  |  0  0
4047:             0  0  0  | 22 23  0  | 24  0
4048:     -------------------------------------
4049:     Proc2  25 26 27  |  0  0 28  | 29  0
4050:            30  0  0  | 31 32 33  |  0 34
4051: .ve

4053:   This can be represented as a collection of submatrices as
4054: .vb
4055:       A B C
4056:       D E F
4057:       G H I
4058: .ve

4060:   Where the submatrices A,B,C are owned by proc0, D,E,F are
4061:   owned by proc1, G,H,I are owned by proc2.

4063:   The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4064:   The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4065:   The 'M','N' parameters are 8,8, and have the same values on all procs.

4067:   The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4068:   submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4069:   corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4070:   Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4071:   part as `MATSEQAIJ` matrices. For example, proc1 will store [E] as a `MATSEQAIJ`
4072:   matrix, and [DF] as another `MATSEQAIJ` matrix.

4074:   When `d_nz`, `o_nz` parameters are specified, `d_nz` storage elements are
4075:   allocated for every row of the local DIAGONAL submatrix, and `o_nz`
4076:   storage locations are allocated for every row of the OFF-DIAGONAL submatrix.
4077:   One way to choose `d_nz` and `o_nz` is to use the maximum number of nonzeros over
4078:   the local rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4079:   In this case, the values of `d_nz`, `o_nz` are
4080: .vb
4081:      proc0  dnz = 2, o_nz = 2
4082:      proc1  dnz = 3, o_nz = 2
4083:      proc2  dnz = 1, o_nz = 4
4084: .ve
4085:   We are allocating `m`*(`d_nz`+`o_nz`) storage locations for every proc. This
4086:   translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4087:   for proc3. i.e we are using 12+15+10=37 storage locations to store
4088:   34 values.

4090:   When `d_nnz`, `o_nnz` parameters are specified, the storage is specified
4091:   for every row, corresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4092:   In the above case the values for `d_nnz`, `o_nnz` are
4093: .vb
4094:      proc0 d_nnz = [2,2,2] and o_nnz = [2,2,2]
4095:      proc1 d_nnz = [3,3,2] and o_nnz = [2,1,1]
4096:      proc2 d_nnz = [1,1]   and o_nnz = [4,4]
4097: .ve
4098:   Here the space allocated is sum of all the above values i.e 34, and
4099:   hence pre-allocation is perfect.

4101:   Level: intermediate

4103:   Notes:
4104:   If the *_nnz parameter is given then the *_nz parameter is ignored

4106:   The `MATAIJ` format, also called compressed row storage (CSR), is compatible with standard Fortran
4107:   storage.  The stored row and column indices begin with zero.
4108:   See [Sparse Matrices](sec_matsparse) for details.

4110:   The parallel matrix is partitioned such that the first m0 rows belong to
4111:   process 0, the next m1 rows belong to process 1, the next m2 rows belong
4112:   to process 2 etc.. where m0,m1,m2... are the input parameter 'm'.

4114:   The DIAGONAL portion of the local submatrix of a processor can be defined
4115:   as the submatrix which is obtained by extraction the part corresponding to
4116:   the rows r1-r2 and columns c1-c2 of the global matrix, where r1 is the
4117:   first row that belongs to the processor, r2 is the last row belonging to
4118:   the this processor, and c1-c2 is range of indices of the local part of a
4119:   vector suitable for applying the matrix to.  This is an mxn matrix.  In the
4120:   common case of a square matrix, the row and column ranges are the same and
4121:   the DIAGONAL part is also square. The remaining portion of the local
4122:   submatrix (mxN) constitute the OFF-DIAGONAL portion.

4124:   If `o_nnz` and `d_nnz` are specified, then `o_nz` and `d_nz` are ignored.

4126:   You can call `MatGetInfo()` to get information on how effective the preallocation was;
4127:   for example the fields mallocs,nz_allocated,nz_used,nz_unneeded;
4128:   You can also run with the option `-info` and look for messages with the string
4129:   malloc in them to see if additional memory allocation was needed.

4131: .seealso: [](ch_matrices), `Mat`, [Sparse Matrices](sec_matsparse), `MATMPIAIJ`, `MATAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatCreateAIJ()`, `MatMPIAIJSetPreallocationCSR()`,
4132:           `MatGetInfo()`, `PetscSplitOwnership()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4133: @*/
4134: PetscErrorCode MatMPIAIJSetPreallocation(Mat B, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[])
4135: {
4136:   PetscFunctionBegin;
4139:   PetscTryMethod(B, "MatMPIAIJSetPreallocation_C", (Mat, PetscInt, const PetscInt[], PetscInt, const PetscInt[]), (B, d_nz, d_nnz, o_nz, o_nnz));
4140:   PetscFunctionReturn(PETSC_SUCCESS);
4141: }

4143: /*@
4144:   MatCreateMPIAIJWithArrays - creates a `MATMPIAIJ` matrix using arrays that contain in standard
4145:   CSR format for the local rows.

4147:   Collective

4149:   Input Parameters:
4150: + comm - MPI communicator
4151: . m    - number of local rows (Cannot be `PETSC_DECIDE`)
4152: . n    - This value should be the same as the local size used in creating the
4153:          x vector for the matrix-vector product $ y = Ax$. (or `PETSC_DECIDE` to have
4154:          calculated if `N` is given) For square matrices n is almost always `m`.
4155: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if `m` is given)
4156: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if `n` is given)
4157: . 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
4158: . j    - global column indices
4159: - a    - optional matrix values

4161:   Output Parameter:
4162: . mat - the matrix

4164:   Level: intermediate

4166:   Notes:
4167:   The `i`, `j`, and `a` arrays ARE copied by this routine into the internal format used by PETSc;
4168:   thus you CANNOT change the matrix entries by changing the values of `a[]` after you have
4169:   called this routine. Use `MatCreateMPIAIJWithSplitArrays()` to avoid needing to copy the arrays.

4171:   The `i` and `j` indices are 0 based, and `i` indices are indices corresponding to the local `j` array.

4173:   Once you have created the matrix you can update it with new numerical values using `MatUpdateMPIAIJWithArray()`

4175:   If you do **not** use `MatUpdateMPIAIJWithArray()`, the column indices in `j` do not need to be sorted. If you will use
4176:   `MatUpdateMPIAIJWithArrays()`, the column indices **must** be sorted.

4178:   The format which is used for the sparse matrix input, is equivalent to a
4179:   row-major ordering, i.e., for the following matrix, the input data expected is
4180:   as shown
4181: .vb
4182:         1 0 0
4183:         2 0 3     P0
4184:        -------
4185:         4 5 6     P1

4187:      Process0 [P0] rows_owned=[0,1]
4188:         i =  {0,1,3}  [size = nrow+1  = 2+1]
4189:         j =  {0,0,2}  [size = 3]
4190:         v =  {1,2,3}  [size = 3]

4192:      Process1 [P1] rows_owned=[2]
4193:         i =  {0,3}    [size = nrow+1  = 1+1]
4194:         j =  {0,1,2}  [size = 3]
4195:         v =  {4,5,6}  [size = 3]
4196: .ve

4198: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4199:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArray()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4200: @*/
4201: PetscErrorCode MatCreateMPIAIJWithArrays(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt M, PetscInt N, const PetscInt i[], const PetscInt j[], const PetscScalar a[], Mat *mat)
4202: {
4203:   PetscFunctionBegin;
4204:   PetscCheck(!i || !i[0], PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
4205:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
4206:   PetscCall(MatCreate(comm, mat));
4207:   PetscCall(MatSetSizes(*mat, m, n, M, N));
4208:   /* PetscCall(MatSetBlockSizes(M,bs,cbs)); */
4209:   PetscCall(MatSetType(*mat, MATMPIAIJ));
4210:   PetscCall(MatMPIAIJSetPreallocationCSR(*mat, i, j, a));
4211:   PetscFunctionReturn(PETSC_SUCCESS);
4212: }

4214: /*@
4215:   MatUpdateMPIAIJWithArrays - updates a `MATMPIAIJ` matrix using arrays that contain in standard
4216:   CSR format for the local rows. Only the numerical values are updated the other arrays must be identical to what was passed
4217:   from `MatCreateMPIAIJWithArrays()`

4219:   Deprecated: Use `MatUpdateMPIAIJWithArray()`

4221:   Collective

4223:   Input Parameters:
4224: + mat - the matrix
4225: . m   - number of local rows (Cannot be `PETSC_DECIDE`)
4226: . n   - This value should be the same as the local size used in creating the
4227:        x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4228:        calculated if N is given) For square matrices n is almost always m.
4229: . M   - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4230: . N   - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4231: . Ii  - row indices; that is Ii[0] = 0, Ii[row] = Ii[row-1] + number of elements in that row of the matrix
4232: . J   - column indices
4233: - v   - matrix values

4235:   Level: deprecated

4237: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4238:           `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArray()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4239: @*/
4240: PetscErrorCode MatUpdateMPIAIJWithArrays(Mat mat, PetscInt m, PetscInt n, PetscInt M, PetscInt N, const PetscInt Ii[], const PetscInt J[], const PetscScalar v[])
4241: {
4242:   PetscInt        nnz, i;
4243:   PetscBool       nooffprocentries;
4244:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)mat->data;
4245:   Mat_SeqAIJ     *Ad  = (Mat_SeqAIJ *)Aij->A->data;
4246:   PetscScalar    *ad, *ao;
4247:   PetscInt        ldi, Iii, md;
4248:   const PetscInt *Adi = Ad->i;
4249:   PetscInt       *ld  = Aij->ld;

4251:   PetscFunctionBegin;
4252:   PetscCheck(Ii[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
4253:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
4254:   PetscCheck(m == mat->rmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Local number of rows cannot change from call to MatUpdateMPIAIJWithArrays()");
4255:   PetscCheck(n == mat->cmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Local number of columns cannot change from call to MatUpdateMPIAIJWithArrays()");

4257:   PetscCall(MatSeqAIJGetArrayWrite(Aij->A, &ad));
4258:   PetscCall(MatSeqAIJGetArrayWrite(Aij->B, &ao));

4260:   for (i = 0; i < m; i++) {
4261:     if (PetscDefined(USE_DEBUG)) {
4262:       for (PetscInt j = Ii[i] + 1; j < Ii[i + 1]; ++j) {
4263:         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);
4264:         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);
4265:       }
4266:     }
4267:     nnz = Ii[i + 1] - Ii[i];
4268:     Iii = Ii[i];
4269:     ldi = ld[i];
4270:     md  = Adi[i + 1] - Adi[i];
4271:     PetscCall(PetscArraycpy(ao, v + Iii, ldi));
4272:     PetscCall(PetscArraycpy(ad, v + Iii + ldi, md));
4273:     PetscCall(PetscArraycpy(ao + ldi, v + Iii + ldi + md, nnz - ldi - md));
4274:     ad += md;
4275:     ao += nnz - md;
4276:   }
4277:   nooffprocentries      = mat->nooffprocentries;
4278:   mat->nooffprocentries = PETSC_TRUE;
4279:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->A, &ad));
4280:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->B, &ao));
4281:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->A));
4282:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->B));
4283:   PetscCall(PetscObjectStateIncrease((PetscObject)mat));
4284:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
4285:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
4286:   mat->nooffprocentries = nooffprocentries;
4287:   PetscFunctionReturn(PETSC_SUCCESS);
4288: }

4290: /*@
4291:   MatUpdateMPIAIJWithArray - updates an `MATMPIAIJ` matrix using an array that contains the nonzero values

4293:   Collective

4295:   Input Parameters:
4296: + mat - the matrix
4297: - v   - matrix values, stored by row

4299:   Level: intermediate

4301:   Notes:
4302:   The matrix must have been obtained with `MatCreateMPIAIJWithArrays()` or `MatMPIAIJSetPreallocationCSR()`

4304:   The column indices in the call to `MatCreateMPIAIJWithArrays()` or `MatMPIAIJSetPreallocationCSR()` must have been sorted for this call to work correctly

4306: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4307:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArrays()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4308: @*/
4309: PetscErrorCode MatUpdateMPIAIJWithArray(Mat mat, const PetscScalar v[])
4310: {
4311:   PetscInt        nnz, i, m;
4312:   PetscBool       nooffprocentries;
4313:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)mat->data;
4314:   Mat_SeqAIJ     *Ad  = (Mat_SeqAIJ *)Aij->A->data;
4315:   Mat_SeqAIJ     *Ao  = (Mat_SeqAIJ *)Aij->B->data;
4316:   PetscScalar    *ad, *ao;
4317:   const PetscInt *Adi = Ad->i, *Adj = Ao->i;
4318:   PetscInt        ldi, Iii, md;
4319:   PetscInt       *ld = Aij->ld;

4321:   PetscFunctionBegin;
4322:   m = mat->rmap->n;

4324:   PetscCall(MatSeqAIJGetArrayWrite(Aij->A, &ad));
4325:   PetscCall(MatSeqAIJGetArrayWrite(Aij->B, &ao));
4326:   Iii = 0;
4327:   for (i = 0; i < m; i++) {
4328:     nnz = Adi[i + 1] - Adi[i] + Adj[i + 1] - Adj[i];
4329:     ldi = ld[i];
4330:     md  = Adi[i + 1] - Adi[i];
4331:     PetscCall(PetscArraycpy(ad, v + Iii + ldi, md));
4332:     ad += md;
4333:     if (ao) {
4334:       PetscCall(PetscArraycpy(ao, v + Iii, ldi));
4335:       PetscCall(PetscArraycpy(ao + ldi, v + Iii + ldi + md, nnz - ldi - md));
4336:       ao += nnz - md;
4337:     }
4338:     Iii += nnz;
4339:   }
4340:   nooffprocentries      = mat->nooffprocentries;
4341:   mat->nooffprocentries = PETSC_TRUE;
4342:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->A, &ad));
4343:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->B, &ao));
4344:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->A));
4345:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->B));
4346:   PetscCall(PetscObjectStateIncrease((PetscObject)mat));
4347:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
4348:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
4349:   mat->nooffprocentries = nooffprocentries;
4350:   PetscFunctionReturn(PETSC_SUCCESS);
4351: }

4353: /*@
4354:   MatCreateAIJ - Creates a sparse parallel matrix in `MATAIJ` format
4355:   (the default parallel PETSc format).  For good matrix assembly performance
4356:   the user should preallocate the matrix storage by setting the parameters
4357:   `d_nz` (or `d_nnz`) and `o_nz` (or `o_nnz`).

4359:   Collective

4361:   Input Parameters:
4362: + comm  - MPI communicator
4363: . m     - number of local rows (or `PETSC_DECIDE` to have calculated if M is given)
4364:           This value should be the same as the local size used in creating the
4365:           y vector for the matrix-vector product y = Ax.
4366: . n     - This value should be the same as the local size used in creating the
4367:           x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4368:           calculated if N is given) For square matrices n is almost always m.
4369: . M     - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4370: . N     - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4371: . d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4372:           (same value is used for all local rows)
4373: . d_nnz - array containing the number of nonzeros in the various rows of the
4374:           DIAGONAL portion of the local submatrix (possibly different for each row)
4375:           or `NULL`, if `d_nz` is used to specify the nonzero structure.
4376:           The size of this array is equal to the number of local rows, i.e 'm'.
4377: . o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4378:           submatrix (same value is used for all local rows).
4379: - o_nnz - array containing the number of nonzeros in the various rows of the
4380:           OFF-DIAGONAL portion of the local submatrix (possibly different for
4381:           each row) or `NULL`, if `o_nz` is used to specify the nonzero
4382:           structure. The size of this array is equal to the number
4383:           of local rows, i.e 'm'.

4385:   Output Parameter:
4386: . A - the matrix

4388:   Options Database Keys:
4389: + -mat_no_inode                     - Do not use inodes
4390: . -mat_inode_limit <limit>          - Sets inode limit (max limit=5)
4391: - -matmult_vecscatter_view <viewer> - View the vecscatter (i.e., communication pattern) used in `MatMult()` of sparse parallel matrices.
4392:                                       See viewer types in manual of `MatView()`. Of them, ascii_matlab, draw or binary cause the `VecScatter`
4393:                                       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.

4395:   Level: intermediate

4397:   Notes:
4398:   It is recommended that one use `MatCreateFromOptions()` or the `MatCreate()`, `MatSetType()` and/or `MatSetFromOptions()`,
4399:   MatXXXXSetPreallocation() paradigm instead of this routine directly.
4400:   [MatXXXXSetPreallocation() is, for example, `MatSeqAIJSetPreallocation()`]

4402:   If the *_nnz parameter is given then the *_nz parameter is ignored

4404:   The `m`,`n`,`M`,`N` parameters specify the size of the matrix, and its partitioning across
4405:   processors, while `d_nz`,`d_nnz`,`o_nz`,`o_nnz` parameters specify the approximate
4406:   storage requirements for this matrix.

4408:   If `PETSC_DECIDE` or  `PETSC_DETERMINE` is used for a particular argument on one
4409:   processor than it must be used on all processors that share the object for
4410:   that argument.

4412:   If `m` and `n` are not `PETSC_DECIDE`, then the values determine the `PetscLayout` of the matrix and the ranges returned by
4413:   `MatGetOwnershipRange()`, `MatGetOwnershipRanges()`, `MatGetOwnershipRangeColumn()`, and `MatGetOwnershipRangesColumn()`.

4415:   The user MUST specify either the local or global matrix dimensions
4416:   (possibly both).

4418:   The parallel matrix is partitioned across processors such that the
4419:   first `m0` rows belong to process 0, the next `m1` rows belong to
4420:   process 1, the next `m2` rows belong to process 2, etc., where
4421:   `m0`, `m1`, `m2`... are the input parameter `m` on each MPI process. I.e., each MPI process stores
4422:   values corresponding to [m x N] submatrix.

4424:   The columns are logically partitioned with the n0 columns belonging
4425:   to 0th partition, the next n1 columns belonging to the next
4426:   partition etc.. where n0,n1,n2... are the input parameter 'n'.

4428:   The DIAGONAL portion of the local submatrix on any given processor
4429:   is the submatrix corresponding to the rows and columns m,n
4430:   corresponding to the given processor. i.e diagonal matrix on
4431:   process 0 is [m0 x n0], diagonal matrix on process 1 is [m1 x n1]
4432:   etc. The remaining portion of the local submatrix [m x (N-n)]
4433:   constitute the OFF-DIAGONAL portion. The example below better
4434:   illustrates this concept. The two matrices, the DIAGONAL portion and
4435:   the OFF-DIAGONAL portion are each stored as `MATSEQAIJ` matrices.

4437:   For a square global matrix we define each processor's diagonal portion
4438:   to be its local rows and the corresponding columns (a square submatrix);
4439:   each processor's off-diagonal portion encompasses the remainder of the
4440:   local matrix (a rectangular submatrix).

4442:   If `o_nnz`, `d_nnz` are specified, then `o_nz`, and `d_nz` are ignored.

4444:   When calling this routine with a single process communicator, a matrix of
4445:   type `MATSEQAIJ` is returned.  If a matrix of type `MATMPIAIJ` is desired for this
4446:   type of communicator, use the construction mechanism
4447: .vb
4448:   MatCreate(..., &A);
4449:   MatSetType(A, MATMPIAIJ);
4450:   MatSetSizes(A, m, n, M, N);
4451:   MatMPIAIJSetPreallocation(A, ...);
4452: .ve

4454:   By default, this format uses inodes (identical nodes) when possible.
4455:   We search for consecutive rows with the same nonzero structure, thereby
4456:   reusing matrix information to achieve increased efficiency.

4458:   Example Usage:
4459:   Consider the following 8x8 matrix with 34 non-zero values, that is
4460:   assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4461:   proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4462:   as follows

4464: .vb
4465:             1  2  0  |  0  3  0  |  0  4
4466:     Proc0   0  5  6  |  7  0  0  |  8  0
4467:             9  0 10  | 11  0  0  | 12  0
4468:     -------------------------------------
4469:            13  0 14  | 15 16 17  |  0  0
4470:     Proc1   0 18  0  | 19 20 21  |  0  0
4471:             0  0  0  | 22 23  0  | 24  0
4472:     -------------------------------------
4473:     Proc2  25 26 27  |  0  0 28  | 29  0
4474:            30  0  0  | 31 32 33  |  0 34
4475: .ve

4477:   This can be represented as a collection of submatrices as

4479: .vb
4480:       A B C
4481:       D E F
4482:       G H I
4483: .ve

4485:   Where the submatrices A,B,C are owned by proc0, D,E,F are
4486:   owned by proc1, G,H,I are owned by proc2.

4488:   The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4489:   The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4490:   The 'M','N' parameters are 8,8, and have the same values on all procs.

4492:   The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4493:   submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4494:   corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4495:   Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4496:   part as `MATSEQAIJ` matrices. For example, proc1 will store [E] as a `MATSEQAIJ`
4497:   matrix, and [DF] as another SeqAIJ matrix.

4499:   When `d_nz`, `o_nz` parameters are specified, `d_nz` storage elements are
4500:   allocated for every row of the local DIAGONAL submatrix, and `o_nz`
4501:   storage locations are allocated for every row of the OFF-DIAGONAL submatrix.
4502:   One way to choose `d_nz` and `o_nz` is to use the maximum number of nonzeros over
4503:   the local rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4504:   In this case, the values of `d_nz`,`o_nz` are
4505: .vb
4506:      proc0  dnz = 2, o_nz = 2
4507:      proc1  dnz = 3, o_nz = 2
4508:      proc2  dnz = 1, o_nz = 4
4509: .ve
4510:   We are allocating m*(`d_nz`+`o_nz`) storage locations for every proc. This
4511:   translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4512:   for proc3. i.e we are using 12+15+10=37 storage locations to store
4513:   34 values.

4515:   When `d_nnz`, `o_nnz` parameters are specified, the storage is specified
4516:   for every row, corresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4517:   In the above case the values for d_nnz,o_nnz are
4518: .vb
4519:      proc0 d_nnz = [2,2,2] and o_nnz = [2,2,2]
4520:      proc1 d_nnz = [3,3,2] and o_nnz = [2,1,1]
4521:      proc2 d_nnz = [1,1]   and o_nnz = [4,4]
4522: .ve
4523:   Here the space allocated is sum of all the above values i.e 34, and
4524:   hence pre-allocation is perfect.

4526: .seealso: [](ch_matrices), `Mat`, [Sparse Matrix Creation](sec_matsparse), `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4527:           `MATMPIAIJ`, `MatCreateMPIAIJWithArrays()`, `MatGetOwnershipRange()`, `MatGetOwnershipRanges()`, `MatGetOwnershipRangeColumn()`,
4528:           `MatGetOwnershipRangesColumn()`, `PetscLayout`
4529: @*/
4530: 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)
4531: {
4532:   PetscMPIInt size;

4534:   PetscFunctionBegin;
4535:   PetscCall(MatCreate(comm, A));
4536:   PetscCall(MatSetSizes(*A, m, n, M, N));
4537:   PetscCallMPI(MPI_Comm_size(comm, &size));
4538:   if (size > 1) {
4539:     PetscCall(MatSetType(*A, MATMPIAIJ));
4540:     PetscCall(MatMPIAIJSetPreallocation(*A, d_nz, d_nnz, o_nz, o_nnz));
4541:   } else {
4542:     PetscCall(MatSetType(*A, MATSEQAIJ));
4543:     PetscCall(MatSeqAIJSetPreallocation(*A, d_nz, d_nnz));
4544:   }
4545:   PetscFunctionReturn(PETSC_SUCCESS);
4546: }

4548: /*@C
4549:   MatMPIAIJGetSeqAIJ - Returns the local pieces of this distributed matrix

4551:   Not Collective

4553:   Input Parameter:
4554: . A - The `MATMPIAIJ` matrix

4556:   Output Parameters:
4557: + Ad     - The local diagonal block as a `MATSEQAIJ` matrix
4558: . Ao     - The local off-diagonal block as a `MATSEQAIJ` matrix
4559: - colmap - An array mapping local column numbers of `Ao` to global column numbers of the parallel matrix

4561:   Level: intermediate

4563:   Note:
4564:   The rows in `Ad` and `Ao` are in [0, Nr), where Nr is the number of local rows on this process. The columns
4565:   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
4566:   the number of nonzero columns in the local off-diagonal piece of the matrix `A`. The array colmap maps these
4567:   local column numbers to global column numbers in the original matrix.

4569: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatMPIAIJGetLocalMat()`, `MatMPIAIJGetLocalMatCondensed()`, `MatCreateAIJ()`, `MATSEQAIJ`
4570: @*/
4571: PetscErrorCode MatMPIAIJGetSeqAIJ(Mat A, Mat *Ad, Mat *Ao, const PetscInt *colmap[])
4572: {
4573:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
4574:   PetscBool   flg;

4576:   PetscFunctionBegin;
4577:   PetscCall(PetscStrbeginswith(((PetscObject)A)->type_name, MATMPIAIJ, &flg));
4578:   PetscCheck(flg, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "This function requires a MATMPIAIJ matrix as input");
4579:   if (Ad) *Ad = a->A;
4580:   if (Ao) *Ao = a->B;
4581:   if (colmap) *colmap = a->garray;
4582:   PetscFunctionReturn(PETSC_SUCCESS);
4583: }

4585: PetscErrorCode MatCreateMPIMatConcatenateSeqMat_MPIAIJ(MPI_Comm comm, Mat inmat, PetscInt n, MatReuse scall, Mat *outmat)
4586: {
4587:   PetscInt     m, N, i, rstart, nnz, Ii;
4588:   PetscInt    *indx;
4589:   PetscScalar *values;
4590:   MatType      rootType;

4592:   PetscFunctionBegin;
4593:   PetscCall(MatGetSize(inmat, &m, &N));
4594:   if (scall == MAT_INITIAL_MATRIX) { /* symbolic phase */
4595:     PetscInt *dnz, *onz, sum, bs, cbs;

4597:     if (n == PETSC_DECIDE) PetscCall(PetscSplitOwnership(comm, &n, &N));
4598:     /* Check sum(n) = N */
4599:     PetscCallMPI(MPIU_Allreduce(&n, &sum, 1, MPIU_INT, MPI_SUM, comm));
4600:     PetscCheck(sum == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Sum of local columns %" PetscInt_FMT " != global columns %" PetscInt_FMT, sum, N);

4602:     PetscCallMPI(MPI_Scan(&m, &rstart, 1, MPIU_INT, MPI_SUM, comm));
4603:     rstart -= m;

4605:     MatPreallocateBegin(comm, m, n, dnz, onz);
4606:     for (i = 0; i < m; i++) {
4607:       PetscCall(MatGetRow_SeqAIJ(inmat, i, &nnz, &indx, NULL));
4608:       PetscCall(MatPreallocateSet(i + rstart, nnz, indx, dnz, onz));
4609:       PetscCall(MatRestoreRow_SeqAIJ(inmat, i, &nnz, &indx, NULL));
4610:     }

4612:     PetscCall(MatCreate(comm, outmat));
4613:     PetscCall(MatSetSizes(*outmat, m, n, PETSC_DETERMINE, PETSC_DETERMINE));
4614:     PetscCall(MatGetBlockSizes(inmat, &bs, &cbs));
4615:     PetscCall(MatSetBlockSizes(*outmat, bs, cbs));
4616:     PetscCall(MatGetRootType_Private(inmat, &rootType));
4617:     PetscCall(MatSetType(*outmat, rootType));
4618:     PetscCall(MatSeqAIJSetPreallocation(*outmat, 0, dnz));
4619:     PetscCall(MatMPIAIJSetPreallocation(*outmat, 0, dnz, 0, onz));
4620:     MatPreallocateEnd(dnz, onz);
4621:     PetscCall(MatSetOption(*outmat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
4622:   }

4624:   /* numeric phase */
4625:   PetscCall(MatGetOwnershipRange(*outmat, &rstart, NULL));
4626:   for (i = 0; i < m; i++) {
4627:     PetscCall(MatGetRow_SeqAIJ(inmat, i, &nnz, &indx, &values));
4628:     Ii = i + rstart;
4629:     PetscCall(MatSetValues(*outmat, 1, &Ii, nnz, indx, values, INSERT_VALUES));
4630:     PetscCall(MatRestoreRow_SeqAIJ(inmat, i, &nnz, &indx, &values));
4631:   }
4632:   PetscCall(MatAssemblyBegin(*outmat, MAT_FINAL_ASSEMBLY));
4633:   PetscCall(MatAssemblyEnd(*outmat, MAT_FINAL_ASSEMBLY));
4634:   PetscFunctionReturn(PETSC_SUCCESS);
4635: }

4637: static PetscErrorCode MatDestroy_MPIAIJ_SeqsToMPI(void **data)
4638: {
4639:   Mat_Merge_SeqsToMPI *merge = (Mat_Merge_SeqsToMPI *)*data;

4641:   PetscFunctionBegin;
4642:   if (!merge) PetscFunctionReturn(PETSC_SUCCESS);
4643:   PetscCall(PetscFree(merge->id_r));
4644:   PetscCall(PetscFree(merge->len_s));
4645:   PetscCall(PetscFree(merge->len_r));
4646:   PetscCall(PetscFree(merge->bi));
4647:   PetscCall(PetscFree(merge->bj));
4648:   PetscCall(PetscFree(merge->buf_ri[0]));
4649:   PetscCall(PetscFree(merge->buf_ri));
4650:   PetscCall(PetscFree(merge->buf_rj[0]));
4651:   PetscCall(PetscFree(merge->buf_rj));
4652:   PetscCall(PetscFree(merge->coi));
4653:   PetscCall(PetscFree(merge->coj));
4654:   PetscCall(PetscFree(merge->owners_co));
4655:   PetscCall(PetscLayoutDestroy(&merge->rowmap));
4656:   PetscCall(PetscFree(merge));
4657:   PetscFunctionReturn(PETSC_SUCCESS);
4658: }

4660: #include <../src/mat/utils/freespace.h>
4661: #include <petscbt.h>

4663: PetscErrorCode MatCreateMPIAIJSumSeqAIJNumeric(Mat seqmat, Mat mpimat)
4664: {
4665:   MPI_Comm             comm;
4666:   Mat_SeqAIJ          *a = (Mat_SeqAIJ *)seqmat->data;
4667:   PetscMPIInt          size, rank, taga, *len_s;
4668:   PetscInt             N = mpimat->cmap->N, i, j, *owners, *ai = a->i, *aj, m;
4669:   PetscMPIInt          proc, k;
4670:   PetscInt           **buf_ri, **buf_rj;
4671:   PetscInt             anzi, *bj_i, *bi, *bj, arow, bnzi, nextaj;
4672:   PetscInt             nrows, **buf_ri_k, **nextrow, **nextai;
4673:   MPI_Request         *s_waits, *r_waits;
4674:   MPI_Status          *status;
4675:   const MatScalar     *aa, *a_a;
4676:   MatScalar          **abuf_r, *ba_i;
4677:   Mat_Merge_SeqsToMPI *merge;
4678:   PetscContainer       container;

4680:   PetscFunctionBegin;
4681:   PetscCall(PetscObjectGetComm((PetscObject)mpimat, &comm));
4682:   PetscCall(PetscLogEventBegin(MAT_Seqstompinum, seqmat, 0, 0, 0));

4684:   PetscCallMPI(MPI_Comm_size(comm, &size));
4685:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

4687:   PetscCall(PetscObjectQuery((PetscObject)mpimat, "MatMergeSeqsToMPI", (PetscObject *)&container));
4688:   PetscCheck(container, PetscObjectComm((PetscObject)mpimat), PETSC_ERR_PLIB, "Mat not created from MatCreateMPIAIJSumSeqAIJSymbolic");
4689:   PetscCall(PetscContainerGetPointer(container, (void **)&merge));
4690:   PetscCall(MatSeqAIJGetArrayRead(seqmat, &a_a));
4691:   aa = a_a;

4693:   bi     = merge->bi;
4694:   bj     = merge->bj;
4695:   buf_ri = merge->buf_ri;
4696:   buf_rj = merge->buf_rj;

4698:   PetscCall(PetscMalloc1(size, &status));
4699:   owners = merge->rowmap->range;
4700:   len_s  = merge->len_s;

4702:   /* send and recv matrix values */
4703:   PetscCall(PetscObjectGetNewTag((PetscObject)mpimat, &taga));
4704:   PetscCall(PetscPostIrecvScalar(comm, taga, merge->nrecv, merge->id_r, merge->len_r, &abuf_r, &r_waits));

4706:   PetscCall(PetscMalloc1(merge->nsend + 1, &s_waits));
4707:   for (proc = 0, k = 0; proc < size; proc++) {
4708:     if (!len_s[proc]) continue;
4709:     i = owners[proc];
4710:     PetscCallMPI(MPIU_Isend(aa + ai[i], len_s[proc], MPIU_MATSCALAR, proc, taga, comm, s_waits + k));
4711:     k++;
4712:   }

4714:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, r_waits, status));
4715:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, s_waits, status));
4716:   PetscCall(PetscFree(status));

4718:   PetscCall(PetscFree(s_waits));
4719:   PetscCall(PetscFree(r_waits));

4721:   /* insert mat values of mpimat */
4722:   PetscCall(PetscMalloc1(N, &ba_i));
4723:   PetscCall(PetscMalloc3(merge->nrecv, &buf_ri_k, merge->nrecv, &nextrow, merge->nrecv, &nextai));

4725:   for (k = 0; k < merge->nrecv; k++) {
4726:     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4727:     nrows       = *buf_ri_k[k];
4728:     nextrow[k]  = buf_ri_k[k] + 1;           /* next row number of k-th recved i-structure */
4729:     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* points to the next i-structure of k-th recved i-structure  */
4730:   }

4732:   /* set values of ba */
4733:   m = merge->rowmap->n;
4734:   for (i = 0; i < m; i++) {
4735:     arow = owners[rank] + i;
4736:     bj_i = bj + bi[i]; /* col indices of the i-th row of mpimat */
4737:     bnzi = bi[i + 1] - bi[i];
4738:     PetscCall(PetscArrayzero(ba_i, bnzi));

4740:     /* add local non-zero vals of this proc's seqmat into ba */
4741:     anzi   = ai[arow + 1] - ai[arow];
4742:     aj     = a->j + ai[arow];
4743:     aa     = a_a + ai[arow];
4744:     nextaj = 0;
4745:     for (j = 0; nextaj < anzi; j++) {
4746:       if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4747:         ba_i[j] += aa[nextaj++];
4748:       }
4749:     }

4751:     /* add received vals into ba */
4752:     for (k = 0; k < merge->nrecv; k++) { /* k-th received message */
4753:       /* i-th row */
4754:       if (i == *nextrow[k]) {
4755:         anzi   = *(nextai[k] + 1) - *nextai[k];
4756:         aj     = buf_rj[k] + *nextai[k];
4757:         aa     = abuf_r[k] + *nextai[k];
4758:         nextaj = 0;
4759:         for (j = 0; nextaj < anzi; j++) {
4760:           if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4761:             ba_i[j] += aa[nextaj++];
4762:           }
4763:         }
4764:         nextrow[k]++;
4765:         nextai[k]++;
4766:       }
4767:     }
4768:     PetscCall(MatSetValues(mpimat, 1, &arow, bnzi, bj_i, ba_i, INSERT_VALUES));
4769:   }
4770:   PetscCall(MatSeqAIJRestoreArrayRead(seqmat, &a_a));
4771:   PetscCall(MatAssemblyBegin(mpimat, MAT_FINAL_ASSEMBLY));
4772:   PetscCall(MatAssemblyEnd(mpimat, MAT_FINAL_ASSEMBLY));

4774:   PetscCall(PetscFree(abuf_r[0]));
4775:   PetscCall(PetscFree(abuf_r));
4776:   PetscCall(PetscFree(ba_i));
4777:   PetscCall(PetscFree3(buf_ri_k, nextrow, nextai));
4778:   PetscCall(PetscLogEventEnd(MAT_Seqstompinum, seqmat, 0, 0, 0));
4779:   PetscFunctionReturn(PETSC_SUCCESS);
4780: }

4782: PetscErrorCode MatCreateMPIAIJSumSeqAIJSymbolic(MPI_Comm comm, Mat seqmat, PetscInt m, PetscInt n, Mat *mpimat)
4783: {
4784:   Mat                  B_mpi;
4785:   Mat_SeqAIJ          *a = (Mat_SeqAIJ *)seqmat->data;
4786:   PetscMPIInt          size, rank, tagi, tagj, *len_s, *len_si, *len_ri;
4787:   PetscInt           **buf_rj, **buf_ri, **buf_ri_k;
4788:   PetscInt             M = seqmat->rmap->n, N = seqmat->cmap->n, i, *owners, *ai = a->i, *aj = a->j;
4789:   PetscInt             len, *dnz, *onz, bs, cbs;
4790:   PetscInt             k, anzi, *bi, *bj, *lnk, nlnk, arow, bnzi;
4791:   PetscInt             nrows, *buf_s, *buf_si, *buf_si_i, **nextrow, **nextai;
4792:   MPI_Request         *si_waits, *sj_waits, *ri_waits, *rj_waits;
4793:   MPI_Status          *status;
4794:   PetscFreeSpaceList   free_space = NULL, current_space = NULL;
4795:   PetscBT              lnkbt;
4796:   Mat_Merge_SeqsToMPI *merge;
4797:   PetscContainer       container;

4799:   PetscFunctionBegin;
4800:   PetscCall(PetscLogEventBegin(MAT_Seqstompisym, seqmat, 0, 0, 0));

4802:   /* make sure it is a PETSc comm */
4803:   PetscCall(PetscCommDuplicate(comm, &comm, NULL));
4804:   PetscCallMPI(MPI_Comm_size(comm, &size));
4805:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

4807:   PetscCall(PetscNew(&merge));
4808:   PetscCall(PetscMalloc1(size, &status));

4810:   /* determine row ownership */
4811:   PetscCall(PetscLayoutCreate(comm, &merge->rowmap));
4812:   PetscCall(PetscLayoutSetLocalSize(merge->rowmap, m));
4813:   PetscCall(PetscLayoutSetSize(merge->rowmap, M));
4814:   PetscCall(PetscLayoutSetBlockSize(merge->rowmap, 1));
4815:   PetscCall(PetscLayoutSetUp(merge->rowmap));
4816:   PetscCall(PetscMalloc1(size, &len_si));
4817:   PetscCall(PetscMalloc1(size, &merge->len_s));

4819:   m      = merge->rowmap->n;
4820:   owners = merge->rowmap->range;

4822:   /* determine the number of messages to send, their lengths */
4823:   len_s = merge->len_s;

4825:   len          = 0; /* length of buf_si[] */
4826:   merge->nsend = 0;
4827:   for (PetscMPIInt proc = 0; proc < size; proc++) {
4828:     len_si[proc] = 0;
4829:     if (proc == rank) {
4830:       len_s[proc] = 0;
4831:     } else {
4832:       PetscCall(PetscMPIIntCast(owners[proc + 1] - owners[proc] + 1, &len_si[proc]));
4833:       PetscCall(PetscMPIIntCast(ai[owners[proc + 1]] - ai[owners[proc]], &len_s[proc])); /* num of rows to be sent to [proc] */
4834:     }
4835:     if (len_s[proc]) {
4836:       merge->nsend++;
4837:       nrows = 0;
4838:       for (i = owners[proc]; i < owners[proc + 1]; i++) {
4839:         if (ai[i + 1] > ai[i]) nrows++;
4840:       }
4841:       PetscCall(PetscMPIIntCast(2 * (nrows + 1), &len_si[proc]));
4842:       len += len_si[proc];
4843:     }
4844:   }

4846:   /* determine the number and length of messages to receive for ij-structure */
4847:   PetscCall(PetscGatherNumberOfMessages(comm, NULL, len_s, &merge->nrecv));
4848:   PetscCall(PetscGatherMessageLengths2(comm, merge->nsend, merge->nrecv, len_s, len_si, &merge->id_r, &merge->len_r, &len_ri));

4850:   /* post the Irecv of j-structure */
4851:   PetscCall(PetscCommGetNewTag(comm, &tagj));
4852:   PetscCall(PetscPostIrecvInt(comm, tagj, merge->nrecv, merge->id_r, merge->len_r, &buf_rj, &rj_waits));

4854:   /* post the Isend of j-structure */
4855:   PetscCall(PetscMalloc2(merge->nsend, &si_waits, merge->nsend, &sj_waits));

4857:   for (PetscMPIInt proc = 0, k = 0; proc < size; proc++) {
4858:     if (!len_s[proc]) continue;
4859:     i = owners[proc];
4860:     PetscCallMPI(MPIU_Isend(aj + ai[i], len_s[proc], MPIU_INT, proc, tagj, comm, sj_waits + k));
4861:     k++;
4862:   }

4864:   /* receives and sends of j-structure are complete */
4865:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, rj_waits, status));
4866:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, sj_waits, status));

4868:   /* send and recv i-structure */
4869:   PetscCall(PetscCommGetNewTag(comm, &tagi));
4870:   PetscCall(PetscPostIrecvInt(comm, tagi, merge->nrecv, merge->id_r, len_ri, &buf_ri, &ri_waits));

4872:   PetscCall(PetscMalloc1(len + 1, &buf_s));
4873:   buf_si = buf_s; /* points to the beginning of k-th msg to be sent */
4874:   for (PetscMPIInt proc = 0, k = 0; proc < size; proc++) {
4875:     if (!len_s[proc]) continue;
4876:     /* form outgoing message for i-structure:
4877:          buf_si[0]:                 nrows to be sent
4878:                [1:nrows]:           row index (global)
4879:                [nrows+1:2*nrows+1]: i-structure index
4880:     */
4881:     nrows       = len_si[proc] / 2 - 1;
4882:     buf_si_i    = buf_si + nrows + 1;
4883:     buf_si[0]   = nrows;
4884:     buf_si_i[0] = 0;
4885:     nrows       = 0;
4886:     for (i = owners[proc]; i < owners[proc + 1]; i++) {
4887:       anzi = ai[i + 1] - ai[i];
4888:       if (anzi) {
4889:         buf_si_i[nrows + 1] = buf_si_i[nrows] + anzi; /* i-structure */
4890:         buf_si[nrows + 1]   = i - owners[proc];       /* local row index */
4891:         nrows++;
4892:       }
4893:     }
4894:     PetscCallMPI(MPIU_Isend(buf_si, len_si[proc], MPIU_INT, proc, tagi, comm, si_waits + k));
4895:     k++;
4896:     buf_si += len_si[proc];
4897:   }

4899:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, ri_waits, status));
4900:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, si_waits, status));

4902:   PetscCall(PetscInfo(seqmat, "nsend: %d, nrecv: %d\n", merge->nsend, merge->nrecv));
4903:   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]));

4905:   PetscCall(PetscFree(len_si));
4906:   PetscCall(PetscFree(len_ri));
4907:   PetscCall(PetscFree(rj_waits));
4908:   PetscCall(PetscFree2(si_waits, sj_waits));
4909:   PetscCall(PetscFree(ri_waits));
4910:   PetscCall(PetscFree(buf_s));
4911:   PetscCall(PetscFree(status));

4913:   /* compute a local seq matrix in each processor */
4914:   /* allocate bi array and free space for accumulating nonzero column info */
4915:   PetscCall(PetscMalloc1(m + 1, &bi));
4916:   bi[0] = 0;

4918:   /* create and initialize a linked list */
4919:   nlnk = N + 1;
4920:   PetscCall(PetscLLCreate(N, N, nlnk, lnk, lnkbt));

4922:   /* initial FreeSpace size is 2*(num of local nnz(seqmat)) */
4923:   len = ai[owners[rank + 1]] - ai[owners[rank]];
4924:   PetscCall(PetscFreeSpaceGet(PetscIntMultTruncate(2, len) + 1, &free_space));

4926:   current_space = free_space;

4928:   /* determine symbolic info for each local row */
4929:   PetscCall(PetscMalloc3(merge->nrecv, &buf_ri_k, merge->nrecv, &nextrow, merge->nrecv, &nextai));

4931:   for (k = 0; k < merge->nrecv; k++) {
4932:     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4933:     nrows       = *buf_ri_k[k];
4934:     nextrow[k]  = buf_ri_k[k] + 1;           /* next row number of k-th recved i-structure */
4935:     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* points to the next i-structure of k-th recved i-structure  */
4936:   }

4938:   MatPreallocateBegin(comm, m, n, dnz, onz);
4939:   len = 0;
4940:   for (i = 0; i < m; i++) {
4941:     bnzi = 0;
4942:     /* add local non-zero cols of this proc's seqmat into lnk */
4943:     arow = owners[rank] + i;
4944:     anzi = ai[arow + 1] - ai[arow];
4945:     aj   = a->j + ai[arow];
4946:     PetscCall(PetscLLAddSorted(anzi, aj, N, &nlnk, lnk, lnkbt));
4947:     bnzi += nlnk;
4948:     /* add received col data into lnk */
4949:     for (k = 0; k < merge->nrecv; k++) { /* k-th received message */
4950:       if (i == *nextrow[k]) {            /* i-th row */
4951:         anzi = *(nextai[k] + 1) - *nextai[k];
4952:         aj   = buf_rj[k] + *nextai[k];
4953:         PetscCall(PetscLLAddSorted(anzi, aj, N, &nlnk, lnk, lnkbt));
4954:         bnzi += nlnk;
4955:         nextrow[k]++;
4956:         nextai[k]++;
4957:       }
4958:     }
4959:     if (len < bnzi) len = bnzi; /* =max(bnzi) */

4961:     /* if free space is not available, make more free space */
4962:     if (current_space->local_remaining < bnzi) PetscCall(PetscFreeSpaceGet(PetscIntSumTruncate(bnzi, current_space->total_array_size), &current_space));
4963:     /* copy data into free space, then initialize lnk */
4964:     PetscCall(PetscLLClean(N, N, bnzi, lnk, current_space->array, lnkbt));
4965:     PetscCall(MatPreallocateSet(i + owners[rank], bnzi, current_space->array, dnz, onz));

4967:     current_space->array += bnzi;
4968:     current_space->local_used += bnzi;
4969:     current_space->local_remaining -= bnzi;

4971:     bi[i + 1] = bi[i] + bnzi;
4972:   }

4974:   PetscCall(PetscFree3(buf_ri_k, nextrow, nextai));

4976:   PetscCall(PetscMalloc1(bi[m] + 1, &bj));
4977:   PetscCall(PetscFreeSpaceContiguous(&free_space, bj));
4978:   PetscCall(PetscLLDestroy(lnk, lnkbt));

4980:   /* create symbolic parallel matrix B_mpi */
4981:   PetscCall(MatGetBlockSizes(seqmat, &bs, &cbs));
4982:   PetscCall(MatCreate(comm, &B_mpi));
4983:   if (n == PETSC_DECIDE) {
4984:     PetscCall(MatSetSizes(B_mpi, m, n, PETSC_DETERMINE, N));
4985:   } else {
4986:     PetscCall(MatSetSizes(B_mpi, m, n, PETSC_DETERMINE, PETSC_DETERMINE));
4987:   }
4988:   PetscCall(MatSetBlockSizes(B_mpi, bs, cbs));
4989:   PetscCall(MatSetType(B_mpi, MATMPIAIJ));
4990:   PetscCall(MatMPIAIJSetPreallocation(B_mpi, 0, dnz, 0, onz));
4991:   MatPreallocateEnd(dnz, onz);
4992:   PetscCall(MatSetOption(B_mpi, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_FALSE));

4994:   /* B_mpi is not ready for use - assembly will be done by MatCreateMPIAIJSumSeqAIJNumeric() */
4995:   B_mpi->assembled = PETSC_FALSE;
4996:   merge->bi        = bi;
4997:   merge->bj        = bj;
4998:   merge->buf_ri    = buf_ri;
4999:   merge->buf_rj    = buf_rj;
5000:   merge->coi       = NULL;
5001:   merge->coj       = NULL;
5002:   merge->owners_co = NULL;

5004:   PetscCall(PetscCommDestroy(&comm));

5006:   /* attach the supporting struct to B_mpi for reuse */
5007:   PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &container));
5008:   PetscCall(PetscContainerSetPointer(container, merge));
5009:   PetscCall(PetscContainerSetCtxDestroy(container, MatDestroy_MPIAIJ_SeqsToMPI));
5010:   PetscCall(PetscObjectCompose((PetscObject)B_mpi, "MatMergeSeqsToMPI", (PetscObject)container));
5011:   PetscCall(PetscContainerDestroy(&container));
5012:   *mpimat = B_mpi;

5014:   PetscCall(PetscLogEventEnd(MAT_Seqstompisym, seqmat, 0, 0, 0));
5015:   PetscFunctionReturn(PETSC_SUCCESS);
5016: }

5018: /*@
5019:   MatCreateMPIAIJSumSeqAIJ - Creates a `MATMPIAIJ` matrix by adding sequential
5020:   matrices from each processor

5022:   Collective

5024:   Input Parameters:
5025: + comm   - the communicators the parallel matrix will live on
5026: . seqmat - the input sequential matrices
5027: . m      - number of local rows (or `PETSC_DECIDE`)
5028: . n      - number of local columns (or `PETSC_DECIDE`)
5029: - scall  - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5031:   Output Parameter:
5032: . mpimat - the parallel matrix generated

5034:   Level: advanced

5036:   Note:
5037:   The dimensions of the sequential matrix in each processor MUST be the same.
5038:   The input seqmat is included into the container "Mat_Merge_SeqsToMPI", and will be
5039:   destroyed when `mpimat` is destroyed. Call `PetscObjectQuery()` to access `seqmat`.

5041: .seealso: [](ch_matrices), `Mat`, `MatCreateAIJ()`
5042: @*/
5043: PetscErrorCode MatCreateMPIAIJSumSeqAIJ(MPI_Comm comm, Mat seqmat, PetscInt m, PetscInt n, MatReuse scall, Mat *mpimat)
5044: {
5045:   PetscMPIInt size;

5047:   PetscFunctionBegin;
5048:   PetscCallMPI(MPI_Comm_size(comm, &size));
5049:   if (size == 1) {
5050:     PetscCall(PetscLogEventBegin(MAT_Seqstompi, seqmat, 0, 0, 0));
5051:     if (scall == MAT_INITIAL_MATRIX) {
5052:       PetscCall(MatDuplicate(seqmat, MAT_COPY_VALUES, mpimat));
5053:     } else {
5054:       PetscCall(MatCopy(seqmat, *mpimat, SAME_NONZERO_PATTERN));
5055:     }
5056:     PetscCall(PetscLogEventEnd(MAT_Seqstompi, seqmat, 0, 0, 0));
5057:     PetscFunctionReturn(PETSC_SUCCESS);
5058:   }
5059:   PetscCall(PetscLogEventBegin(MAT_Seqstompi, seqmat, 0, 0, 0));
5060:   if (scall == MAT_INITIAL_MATRIX) PetscCall(MatCreateMPIAIJSumSeqAIJSymbolic(comm, seqmat, m, n, mpimat));
5061:   PetscCall(MatCreateMPIAIJSumSeqAIJNumeric(seqmat, *mpimat));
5062:   PetscCall(PetscLogEventEnd(MAT_Seqstompi, seqmat, 0, 0, 0));
5063:   PetscFunctionReturn(PETSC_SUCCESS);
5064: }

5066: /*@
5067:   MatAIJGetLocalMat - Creates a `MATSEQAIJ` from a `MATAIJ` matrix.

5069:   Not Collective

5071:   Input Parameter:
5072: . A - the matrix

5074:   Output Parameter:
5075: . A_loc - the local sequential matrix generated

5077:   Level: developer

5079:   Notes:
5080:   The matrix is created by taking `A`'s local rows and putting them into a sequential matrix
5081:   with `mlocal` rows and `n` columns. Where `mlocal` is obtained with `MatGetLocalSize()` and
5082:   `n` is the global column count obtained with `MatGetSize()`

5084:   In other words combines the two parts of a parallel `MATMPIAIJ` matrix on each process to a single matrix.

5086:   For parallel matrices this creates an entirely new matrix. If the matrix is sequential it merely increases the reference count.

5088:   Destroy the matrix with `MatDestroy()`

5090: .seealso: [](ch_matrices), `Mat`, `MatMPIAIJGetLocalMat()`
5091: @*/
5092: PetscErrorCode MatAIJGetLocalMat(Mat A, Mat *A_loc)
5093: {
5094:   PetscBool mpi;

5096:   PetscFunctionBegin;
5097:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATMPIAIJ, &mpi));
5098:   if (mpi) {
5099:     PetscCall(MatMPIAIJGetLocalMat(A, MAT_INITIAL_MATRIX, A_loc));
5100:   } else {
5101:     *A_loc = A;
5102:     PetscCall(PetscObjectReference((PetscObject)*A_loc));
5103:   }
5104:   PetscFunctionReturn(PETSC_SUCCESS);
5105: }

5107: /*@
5108:   MatMPIAIJGetLocalMat - Creates a `MATSEQAIJ` from a `MATMPIAIJ` matrix.

5110:   Not Collective

5112:   Input Parameters:
5113: + A     - the matrix
5114: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5116:   Output Parameter:
5117: . A_loc - the local sequential matrix generated

5119:   Level: developer

5121:   Notes:
5122:   The matrix is created by taking all `A`'s local rows and putting them into a sequential
5123:   matrix with `mlocal` rows and `n` columns.`mlocal` is the row count obtained with
5124:   `MatGetLocalSize()` and `n` is the global column count obtained with `MatGetSize()`.

5126:   In other words combines the two parts of a parallel `MATMPIAIJ` matrix on each process to a single matrix.

5128:   When `A` is sequential and `MAT_INITIAL_MATRIX` is requested, the matrix returned is the diagonal part of `A` (which contains the entire matrix),
5129:   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
5130:   then `MatCopy`(Adiag,*`A_loc`,`SAME_NONZERO_PATTERN`) is called to fill `A_loc`. Thus one can preallocate the appropriate sequential matrix `A_loc`
5131:   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.

5133: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMatCondensed()`, `MatMPIAIJGetLocalMatMerge()`
5134: @*/
5135: PetscErrorCode MatMPIAIJGetLocalMat(Mat A, MatReuse scall, Mat *A_loc)
5136: {
5137:   Mat_MPIAIJ        *mpimat = (Mat_MPIAIJ *)A->data;
5138:   Mat_SeqAIJ        *mat, *a, *b;
5139:   PetscInt          *ai, *aj, *bi, *bj, *cmap = mpimat->garray;
5140:   const PetscScalar *aa, *ba, *aav, *bav;
5141:   PetscScalar       *ca, *cam;
5142:   PetscMPIInt        size;
5143:   PetscInt           am = A->rmap->n, i, j, k, cstart = A->cmap->rstart;
5144:   PetscInt          *ci, *cj, col, ncols_d, ncols_o, jo;
5145:   PetscBool          match;

5147:   PetscFunctionBegin;
5148:   PetscCall(PetscStrbeginswith(((PetscObject)A)->type_name, MATMPIAIJ, &match));
5149:   PetscCheck(match, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Requires MATMPIAIJ matrix as input");
5150:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)A), &size));
5151:   if (size == 1) {
5152:     if (scall == MAT_INITIAL_MATRIX) {
5153:       PetscCall(PetscObjectReference((PetscObject)mpimat->A));
5154:       *A_loc = mpimat->A;
5155:     } else if (scall == MAT_REUSE_MATRIX) {
5156:       PetscCall(MatCopy(mpimat->A, *A_loc, SAME_NONZERO_PATTERN));
5157:     }
5158:     PetscFunctionReturn(PETSC_SUCCESS);
5159:   }

5161:   PetscCall(PetscLogEventBegin(MAT_Getlocalmat, A, 0, 0, 0));
5162:   a  = (Mat_SeqAIJ *)mpimat->A->data;
5163:   b  = (Mat_SeqAIJ *)mpimat->B->data;
5164:   ai = a->i;
5165:   aj = a->j;
5166:   bi = b->i;
5167:   bj = b->j;
5168:   PetscCall(MatSeqAIJGetArrayRead(mpimat->A, &aav));
5169:   PetscCall(MatSeqAIJGetArrayRead(mpimat->B, &bav));
5170:   aa = aav;
5171:   ba = bav;
5172:   if (scall == MAT_INITIAL_MATRIX) {
5173:     PetscCall(PetscMalloc1(1 + am, &ci));
5174:     ci[0] = 0;
5175:     for (i = 0; i < am; i++) ci[i + 1] = ci[i] + (ai[i + 1] - ai[i]) + (bi[i + 1] - bi[i]);
5176:     PetscCall(PetscMalloc1(1 + ci[am], &cj));
5177:     PetscCall(PetscMalloc1(1 + ci[am], &ca));
5178:     k = 0;
5179:     for (i = 0; i < am; i++) {
5180:       ncols_o = bi[i + 1] - bi[i];
5181:       ncols_d = ai[i + 1] - ai[i];
5182:       /* off-diagonal portion of A */
5183:       for (jo = 0; jo < ncols_o; jo++) {
5184:         col = cmap[*bj];
5185:         if (col >= cstart) break;
5186:         cj[k] = col;
5187:         bj++;
5188:         ca[k++] = *ba++;
5189:       }
5190:       /* diagonal portion of A */
5191:       for (j = 0; j < ncols_d; j++) {
5192:         cj[k]   = cstart + *aj++;
5193:         ca[k++] = *aa++;
5194:       }
5195:       /* off-diagonal portion of A */
5196:       for (j = jo; j < ncols_o; j++) {
5197:         cj[k]   = cmap[*bj++];
5198:         ca[k++] = *ba++;
5199:       }
5200:     }
5201:     /* put together the new matrix */
5202:     PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, am, A->cmap->N, ci, cj, ca, A_loc));
5203:     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5204:     /* Since these are PETSc arrays, change flags to free them as necessary. */
5205:     mat          = (Mat_SeqAIJ *)(*A_loc)->data;
5206:     mat->free_a  = PETSC_TRUE;
5207:     mat->free_ij = PETSC_TRUE;
5208:     mat->nonew   = 0;
5209:   } else if (scall == MAT_REUSE_MATRIX) {
5210:     mat = (Mat_SeqAIJ *)(*A_loc)->data;
5211:     ci  = mat->i;
5212:     cj  = mat->j;
5213:     PetscCall(MatSeqAIJGetArrayWrite(*A_loc, &cam));
5214:     for (i = 0; i < am; i++) {
5215:       /* off-diagonal portion of A */
5216:       ncols_o = bi[i + 1] - bi[i];
5217:       for (jo = 0; jo < ncols_o; jo++) {
5218:         col = cmap[*bj];
5219:         if (col >= cstart) break;
5220:         *cam++ = *ba++;
5221:         bj++;
5222:       }
5223:       /* diagonal portion of A */
5224:       ncols_d = ai[i + 1] - ai[i];
5225:       for (j = 0; j < ncols_d; j++) *cam++ = *aa++;
5226:       /* off-diagonal portion of A */
5227:       for (j = jo; j < ncols_o; j++) {
5228:         *cam++ = *ba++;
5229:         bj++;
5230:       }
5231:     }
5232:     PetscCall(MatSeqAIJRestoreArrayWrite(*A_loc, &cam));
5233:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid MatReuse %d", (int)scall);
5234:   PetscCall(MatSeqAIJRestoreArrayRead(mpimat->A, &aav));
5235:   PetscCall(MatSeqAIJRestoreArrayRead(mpimat->B, &bav));
5236:   PetscCall(PetscLogEventEnd(MAT_Getlocalmat, A, 0, 0, 0));
5237:   PetscFunctionReturn(PETSC_SUCCESS);
5238: }

5240: /*@
5241:   MatMPIAIJGetLocalMatMerge - Creates a `MATSEQAIJ` from a `MATMPIAIJ` matrix by taking all its local rows and putting them into a sequential matrix with
5242:   mlocal rows and n columns. Where n is the sum of the number of columns of the diagonal and off-diagonal part

5244:   Not Collective

5246:   Input Parameters:
5247: + A     - the matrix
5248: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5250:   Output Parameters:
5251: + glob  - sequential `IS` with global indices associated with the columns of the local sequential matrix generated (can be `NULL`)
5252: - A_loc - the local sequential matrix generated

5254:   Level: developer

5256:   Note:
5257:   This is different from `MatMPIAIJGetLocalMat()` since the first columns in the returning matrix are those associated with the diagonal
5258:   part, then those associated with the off-diagonal part (in its local ordering)

5260: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMat()`, `MatMPIAIJGetLocalMatCondensed()`
5261: @*/
5262: PetscErrorCode MatMPIAIJGetLocalMatMerge(Mat A, MatReuse scall, IS *glob, Mat *A_loc)
5263: {
5264:   Mat             Ao, Ad;
5265:   const PetscInt *cmap;
5266:   PetscMPIInt     size;
5267:   PetscErrorCode (*f)(Mat, MatReuse, IS *, Mat *);

5269:   PetscFunctionBegin;
5270:   PetscCall(MatMPIAIJGetSeqAIJ(A, &Ad, &Ao, &cmap));
5271:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)A), &size));
5272:   if (size == 1) {
5273:     if (scall == MAT_INITIAL_MATRIX) {
5274:       PetscCall(PetscObjectReference((PetscObject)Ad));
5275:       *A_loc = Ad;
5276:     } else if (scall == MAT_REUSE_MATRIX) {
5277:       PetscCall(MatCopy(Ad, *A_loc, SAME_NONZERO_PATTERN));
5278:     }
5279:     if (glob) PetscCall(ISCreateStride(PetscObjectComm((PetscObject)Ad), Ad->cmap->n, Ad->cmap->rstart, 1, glob));
5280:     PetscFunctionReturn(PETSC_SUCCESS);
5281:   }
5282:   PetscCall(PetscObjectQueryFunction((PetscObject)A, "MatMPIAIJGetLocalMatMerge_C", &f));
5283:   PetscCall(PetscLogEventBegin(MAT_Getlocalmat, A, 0, 0, 0));
5284:   if (f) {
5285:     PetscCall((*f)(A, scall, glob, A_loc));
5286:   } else {
5287:     Mat_SeqAIJ        *a = (Mat_SeqAIJ *)Ad->data;
5288:     Mat_SeqAIJ        *b = (Mat_SeqAIJ *)Ao->data;
5289:     Mat_SeqAIJ        *c;
5290:     PetscInt          *ai = a->i, *aj = a->j;
5291:     PetscInt          *bi = b->i, *bj = b->j;
5292:     PetscInt          *ci, *cj;
5293:     const PetscScalar *aa, *ba;
5294:     PetscScalar       *ca;
5295:     PetscInt           i, j, am, dn, on;

5297:     PetscCall(MatGetLocalSize(Ad, &am, &dn));
5298:     PetscCall(MatGetLocalSize(Ao, NULL, &on));
5299:     PetscCall(MatSeqAIJGetArrayRead(Ad, &aa));
5300:     PetscCall(MatSeqAIJGetArrayRead(Ao, &ba));
5301:     if (scall == MAT_INITIAL_MATRIX) {
5302:       PetscInt k;
5303:       PetscCall(PetscMalloc1(1 + am, &ci));
5304:       PetscCall(PetscMalloc1(ai[am] + bi[am], &cj));
5305:       PetscCall(PetscMalloc1(ai[am] + bi[am], &ca));
5306:       ci[0] = 0;
5307:       for (i = 0, k = 0; i < am; i++) {
5308:         const PetscInt ncols_o = bi[i + 1] - bi[i];
5309:         const PetscInt ncols_d = ai[i + 1] - ai[i];
5310:         ci[i + 1]              = ci[i] + ncols_o + ncols_d;
5311:         /* diagonal portion of A */
5312:         for (j = 0; j < ncols_d; j++, k++) {
5313:           cj[k] = *aj++;
5314:           ca[k] = *aa++;
5315:         }
5316:         /* off-diagonal portion of A */
5317:         for (j = 0; j < ncols_o; j++, k++) {
5318:           cj[k] = dn + *bj++;
5319:           ca[k] = *ba++;
5320:         }
5321:       }
5322:       /* put together the new matrix */
5323:       PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, am, dn + on, ci, cj, ca, A_loc));
5324:       /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5325:       /* Since these are PETSc arrays, change flags to free them as necessary. */
5326:       c          = (Mat_SeqAIJ *)(*A_loc)->data;
5327:       c->free_a  = PETSC_TRUE;
5328:       c->free_ij = PETSC_TRUE;
5329:       c->nonew   = 0;
5330:       PetscCall(MatSetType(*A_loc, ((PetscObject)Ad)->type_name));
5331:     } else if (scall == MAT_REUSE_MATRIX) {
5332:       PetscCall(MatSeqAIJGetArrayWrite(*A_loc, &ca));
5333:       for (i = 0; i < am; i++) {
5334:         const PetscInt ncols_d = ai[i + 1] - ai[i];
5335:         const PetscInt ncols_o = bi[i + 1] - bi[i];
5336:         /* diagonal portion of A */
5337:         for (j = 0; j < ncols_d; j++) *ca++ = *aa++;
5338:         /* off-diagonal portion of A */
5339:         for (j = 0; j < ncols_o; j++) *ca++ = *ba++;
5340:       }
5341:       PetscCall(MatSeqAIJRestoreArrayWrite(*A_loc, &ca));
5342:     } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid MatReuse %d", (int)scall);
5343:     PetscCall(MatSeqAIJRestoreArrayRead(Ad, &aa));
5344:     PetscCall(MatSeqAIJRestoreArrayRead(Ao, &aa));
5345:     if (glob) {
5346:       PetscInt cst, *gidx;

5348:       PetscCall(MatGetOwnershipRangeColumn(A, &cst, NULL));
5349:       PetscCall(PetscMalloc1(dn + on, &gidx));
5350:       for (i = 0; i < dn; i++) gidx[i] = cst + i;
5351:       for (i = 0; i < on; i++) gidx[i + dn] = cmap[i];
5352:       PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)Ad), dn + on, gidx, PETSC_OWN_POINTER, glob));
5353:     }
5354:   }
5355:   PetscCall(PetscLogEventEnd(MAT_Getlocalmat, A, 0, 0, 0));
5356:   PetscFunctionReturn(PETSC_SUCCESS);
5357: }

5359: /*@C
5360:   MatMPIAIJGetLocalMatCondensed - Creates a `MATSEQAIJ` matrix from an `MATMPIAIJ` matrix by taking all its local rows and NON-ZERO columns

5362:   Not Collective

5364:   Input Parameters:
5365: + A     - the matrix
5366: . scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`
5367: . row   - index set of rows to extract (or `NULL`)
5368: - col   - index set of columns to extract (or `NULL`)

5370:   Output Parameter:
5371: . A_loc - the local sequential matrix generated

5373:   Level: developer

5375: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMat()`
5376: @*/
5377: PetscErrorCode MatMPIAIJGetLocalMatCondensed(Mat A, MatReuse scall, IS *row, IS *col, Mat *A_loc)
5378: {
5379:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
5380:   PetscInt    i, start, end, ncols, nzA, nzB, *cmap, imark, *idx;
5381:   IS          isrowa, iscola;
5382:   Mat        *aloc;
5383:   PetscBool   match;

5385:   PetscFunctionBegin;
5386:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATMPIAIJ, &match));
5387:   PetscCheck(match, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Requires MATMPIAIJ matrix as input");
5388:   PetscCall(PetscLogEventBegin(MAT_Getlocalmatcondensed, A, 0, 0, 0));
5389:   if (!row) {
5390:     start = A->rmap->rstart;
5391:     end   = A->rmap->rend;
5392:     PetscCall(ISCreateStride(PETSC_COMM_SELF, end - start, start, 1, &isrowa));
5393:   } else {
5394:     isrowa = *row;
5395:   }
5396:   if (!col) {
5397:     start = A->cmap->rstart;
5398:     cmap  = a->garray;
5399:     nzA   = a->A->cmap->n;
5400:     nzB   = a->B->cmap->n;
5401:     PetscCall(PetscMalloc1(nzA + nzB, &idx));
5402:     ncols = 0;
5403:     for (i = 0; i < nzB; i++) {
5404:       if (cmap[i] < start) idx[ncols++] = cmap[i];
5405:       else break;
5406:     }
5407:     imark = i;
5408:     for (i = 0; i < nzA; i++) idx[ncols++] = start + i;
5409:     for (i = imark; i < nzB; i++) idx[ncols++] = cmap[i];
5410:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, &iscola));
5411:   } else {
5412:     iscola = *col;
5413:   }
5414:   if (scall != MAT_INITIAL_MATRIX) {
5415:     PetscCall(PetscMalloc1(1, &aloc));
5416:     aloc[0] = *A_loc;
5417:   }
5418:   PetscCall(MatCreateSubMatrices(A, 1, &isrowa, &iscola, scall, &aloc));
5419:   if (!col) { /* attach global id of condensed columns */
5420:     PetscCall(PetscObjectCompose((PetscObject)aloc[0], "_petsc_GetLocalMatCondensed_iscol", (PetscObject)iscola));
5421:   }
5422:   *A_loc = aloc[0];
5423:   PetscCall(PetscFree(aloc));
5424:   if (!row) PetscCall(ISDestroy(&isrowa));
5425:   if (!col) PetscCall(ISDestroy(&iscola));
5426:   PetscCall(PetscLogEventEnd(MAT_Getlocalmatcondensed, A, 0, 0, 0));
5427:   PetscFunctionReturn(PETSC_SUCCESS);
5428: }

5430: /*
5431:  * Create a sequential AIJ matrix based on row indices. a whole column is extracted once a row is matched.
5432:  * Row could be local or remote.The routine is designed to be scalable in memory so that nothing is based
5433:  * on a global size.
5434:  * */
5435: static PetscErrorCode MatCreateSeqSubMatrixWithRows_Private(Mat P, IS rows, Mat *P_oth)
5436: {
5437:   Mat_MPIAIJ            *p  = (Mat_MPIAIJ *)P->data;
5438:   Mat_SeqAIJ            *pd = (Mat_SeqAIJ *)p->A->data, *po = (Mat_SeqAIJ *)p->B->data, *p_oth;
5439:   PetscInt               plocalsize, nrows, *ilocal, *oilocal, i, lidx, *nrcols, *nlcols, ncol;
5440:   PetscMPIInt            owner;
5441:   PetscSFNode           *iremote, *oiremote;
5442:   const PetscInt        *lrowindices;
5443:   PetscSF                sf, osf;
5444:   PetscInt               pcstart, *roffsets, *loffsets, *pnnz, j;
5445:   PetscInt               ontotalcols, dntotalcols, ntotalcols, nout;
5446:   MPI_Comm               comm;
5447:   ISLocalToGlobalMapping mapping;
5448:   const PetscScalar     *pd_a, *po_a;

5450:   PetscFunctionBegin;
5451:   PetscCall(PetscObjectGetComm((PetscObject)P, &comm));
5452:   /* plocalsize is the number of roots
5453:    * nrows is the number of leaves
5454:    * */
5455:   PetscCall(MatGetLocalSize(P, &plocalsize, NULL));
5456:   PetscCall(ISGetLocalSize(rows, &nrows));
5457:   PetscCall(PetscCalloc1(nrows, &iremote));
5458:   PetscCall(ISGetIndices(rows, &lrowindices));
5459:   for (i = 0; i < nrows; i++) {
5460:     /* Find a remote index and an owner for a row
5461:      * The row could be local or remote
5462:      * */
5463:     owner = 0;
5464:     lidx  = 0;
5465:     PetscCall(PetscLayoutFindOwnerIndex(P->rmap, lrowindices[i], &owner, &lidx));
5466:     iremote[i].index = lidx;
5467:     iremote[i].rank  = owner;
5468:   }
5469:   /* Create SF to communicate how many nonzero columns for each row */
5470:   PetscCall(PetscSFCreate(comm, &sf));
5471:   /* SF will figure out the number of nonzero columns for each row, and their
5472:    * offsets
5473:    * */
5474:   PetscCall(PetscSFSetGraph(sf, plocalsize, nrows, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
5475:   PetscCall(PetscSFSetFromOptions(sf));
5476:   PetscCall(PetscSFSetUp(sf));

5478:   PetscCall(PetscCalloc1(2 * (plocalsize + 1), &roffsets));
5479:   PetscCall(PetscCalloc1(2 * plocalsize, &nrcols));
5480:   PetscCall(PetscCalloc1(nrows, &pnnz));
5481:   roffsets[0] = 0;
5482:   roffsets[1] = 0;
5483:   for (i = 0; i < plocalsize; i++) {
5484:     /* diagonal */
5485:     nrcols[i * 2 + 0] = pd->i[i + 1] - pd->i[i];
5486:     /* off-diagonal */
5487:     nrcols[i * 2 + 1] = po->i[i + 1] - po->i[i];
5488:     /* compute offsets so that we relative location for each row */
5489:     roffsets[(i + 1) * 2 + 0] = roffsets[i * 2 + 0] + nrcols[i * 2 + 0];
5490:     roffsets[(i + 1) * 2 + 1] = roffsets[i * 2 + 1] + nrcols[i * 2 + 1];
5491:   }
5492:   PetscCall(PetscCalloc1(2 * nrows, &nlcols));
5493:   PetscCall(PetscCalloc1(2 * nrows, &loffsets));
5494:   /* 'r' means root, and 'l' means leaf */
5495:   PetscCall(PetscSFBcastBegin(sf, MPIU_2INT, nrcols, nlcols, MPI_REPLACE));
5496:   PetscCall(PetscSFBcastBegin(sf, MPIU_2INT, roffsets, loffsets, MPI_REPLACE));
5497:   PetscCall(PetscSFBcastEnd(sf, MPIU_2INT, nrcols, nlcols, MPI_REPLACE));
5498:   PetscCall(PetscSFBcastEnd(sf, MPIU_2INT, roffsets, loffsets, MPI_REPLACE));
5499:   PetscCall(PetscSFDestroy(&sf));
5500:   PetscCall(PetscFree(roffsets));
5501:   PetscCall(PetscFree(nrcols));
5502:   dntotalcols = 0;
5503:   ontotalcols = 0;
5504:   ncol        = 0;
5505:   for (i = 0; i < nrows; i++) {
5506:     pnnz[i] = nlcols[i * 2 + 0] + nlcols[i * 2 + 1];
5507:     ncol    = PetscMax(pnnz[i], ncol);
5508:     /* diagonal */
5509:     dntotalcols += nlcols[i * 2 + 0];
5510:     /* off-diagonal */
5511:     ontotalcols += nlcols[i * 2 + 1];
5512:   }
5513:   /* We do not need to figure the right number of columns
5514:    * since all the calculations will be done by going through the raw data
5515:    * */
5516:   PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, nrows, ncol, 0, pnnz, P_oth));
5517:   PetscCall(MatSetUp(*P_oth));
5518:   PetscCall(PetscFree(pnnz));
5519:   p_oth = (Mat_SeqAIJ *)(*P_oth)->data;
5520:   /* diagonal */
5521:   PetscCall(PetscCalloc1(dntotalcols, &iremote));
5522:   /* off-diagonal */
5523:   PetscCall(PetscCalloc1(ontotalcols, &oiremote));
5524:   /* diagonal */
5525:   PetscCall(PetscCalloc1(dntotalcols, &ilocal));
5526:   /* off-diagonal */
5527:   PetscCall(PetscCalloc1(ontotalcols, &oilocal));
5528:   dntotalcols = 0;
5529:   ontotalcols = 0;
5530:   ntotalcols  = 0;
5531:   for (i = 0; i < nrows; i++) {
5532:     owner = 0;
5533:     PetscCall(PetscLayoutFindOwnerIndex(P->rmap, lrowindices[i], &owner, NULL));
5534:     /* Set iremote for diag matrix */
5535:     for (j = 0; j < nlcols[i * 2 + 0]; j++) {
5536:       iremote[dntotalcols].index = loffsets[i * 2 + 0] + j;
5537:       iremote[dntotalcols].rank  = owner;
5538:       /* P_oth is seqAIJ so that ilocal need to point to the first part of memory */
5539:       ilocal[dntotalcols++] = ntotalcols++;
5540:     }
5541:     /* off-diagonal */
5542:     for (j = 0; j < nlcols[i * 2 + 1]; j++) {
5543:       oiremote[ontotalcols].index = loffsets[i * 2 + 1] + j;
5544:       oiremote[ontotalcols].rank  = owner;
5545:       oilocal[ontotalcols++]      = ntotalcols++;
5546:     }
5547:   }
5548:   PetscCall(ISRestoreIndices(rows, &lrowindices));
5549:   PetscCall(PetscFree(loffsets));
5550:   PetscCall(PetscFree(nlcols));
5551:   PetscCall(PetscSFCreate(comm, &sf));
5552:   /* P serves as roots and P_oth is leaves
5553:    * Diag matrix
5554:    * */
5555:   PetscCall(PetscSFSetGraph(sf, pd->i[plocalsize], dntotalcols, ilocal, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
5556:   PetscCall(PetscSFSetFromOptions(sf));
5557:   PetscCall(PetscSFSetUp(sf));

5559:   PetscCall(PetscSFCreate(comm, &osf));
5560:   /* off-diagonal */
5561:   PetscCall(PetscSFSetGraph(osf, po->i[plocalsize], ontotalcols, oilocal, PETSC_OWN_POINTER, oiremote, PETSC_OWN_POINTER));
5562:   PetscCall(PetscSFSetFromOptions(osf));
5563:   PetscCall(PetscSFSetUp(osf));
5564:   PetscCall(MatSeqAIJGetArrayRead(p->A, &pd_a));
5565:   PetscCall(MatSeqAIJGetArrayRead(p->B, &po_a));
5566:   /* operate on the matrix internal data to save memory */
5567:   PetscCall(PetscSFBcastBegin(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5568:   PetscCall(PetscSFBcastBegin(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5569:   PetscCall(MatGetOwnershipRangeColumn(P, &pcstart, NULL));
5570:   /* Convert to global indices for diag matrix */
5571:   for (i = 0; i < pd->i[plocalsize]; i++) pd->j[i] += pcstart;
5572:   PetscCall(PetscSFBcastBegin(sf, MPIU_INT, pd->j, p_oth->j, MPI_REPLACE));
5573:   /* We want P_oth store global indices */
5574:   PetscCall(ISLocalToGlobalMappingCreate(comm, 1, p->B->cmap->n, p->garray, PETSC_COPY_VALUES, &mapping));
5575:   /* Use memory scalable approach */
5576:   PetscCall(ISLocalToGlobalMappingSetType(mapping, ISLOCALTOGLOBALMAPPINGHASH));
5577:   PetscCall(ISLocalToGlobalMappingApply(mapping, po->i[plocalsize], po->j, po->j));
5578:   PetscCall(PetscSFBcastBegin(osf, MPIU_INT, po->j, p_oth->j, MPI_REPLACE));
5579:   PetscCall(PetscSFBcastEnd(sf, MPIU_INT, pd->j, p_oth->j, MPI_REPLACE));
5580:   /* Convert back to local indices */
5581:   for (i = 0; i < pd->i[plocalsize]; i++) pd->j[i] -= pcstart;
5582:   PetscCall(PetscSFBcastEnd(osf, MPIU_INT, po->j, p_oth->j, MPI_REPLACE));
5583:   nout = 0;
5584:   PetscCall(ISGlobalToLocalMappingApply(mapping, IS_GTOLM_DROP, po->i[plocalsize], po->j, &nout, po->j));
5585:   PetscCheck(nout == po->i[plocalsize], comm, PETSC_ERR_ARG_INCOMP, "n %" PetscInt_FMT " does not equal to nout %" PetscInt_FMT " ", po->i[plocalsize], nout);
5586:   PetscCall(ISLocalToGlobalMappingDestroy(&mapping));
5587:   /* Exchange values */
5588:   PetscCall(PetscSFBcastEnd(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5589:   PetscCall(PetscSFBcastEnd(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5590:   PetscCall(MatSeqAIJRestoreArrayRead(p->A, &pd_a));
5591:   PetscCall(MatSeqAIJRestoreArrayRead(p->B, &po_a));
5592:   /* Stop PETSc from shrinking memory */
5593:   for (i = 0; i < nrows; i++) p_oth->ilen[i] = p_oth->imax[i];
5594:   PetscCall(MatAssemblyBegin(*P_oth, MAT_FINAL_ASSEMBLY));
5595:   PetscCall(MatAssemblyEnd(*P_oth, MAT_FINAL_ASSEMBLY));
5596:   /* Attach PetscSF objects to P_oth so that we can reuse it later */
5597:   PetscCall(PetscObjectCompose((PetscObject)*P_oth, "diagsf", (PetscObject)sf));
5598:   PetscCall(PetscObjectCompose((PetscObject)*P_oth, "offdiagsf", (PetscObject)osf));
5599:   PetscCall(PetscSFDestroy(&sf));
5600:   PetscCall(PetscSFDestroy(&osf));
5601:   PetscFunctionReturn(PETSC_SUCCESS);
5602: }

5604: /*
5605:  * Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns of local A
5606:  * This supports MPIAIJ and MAIJ
5607:  * */
5608: PetscErrorCode MatGetBrowsOfAcols_MPIXAIJ(Mat A, Mat P, PetscInt dof, MatReuse reuse, Mat *P_oth)
5609: {
5610:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data, *p = (Mat_MPIAIJ *)P->data;
5611:   Mat_SeqAIJ *p_oth;
5612:   IS          rows, map;
5613:   PetscHMapI  hamp;
5614:   PetscInt    i, htsize, *rowindices, off, *mapping, key, count;
5615:   MPI_Comm    comm;
5616:   PetscSF     sf, osf;
5617:   PetscBool   has;

5619:   PetscFunctionBegin;
5620:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
5621:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAocols, A, P, 0, 0));
5622:   /* If it is the first time, create an index set of off-diag nonzero columns of A,
5623:    *  and then create a submatrix (that often is an overlapping matrix)
5624:    * */
5625:   if (reuse == MAT_INITIAL_MATRIX) {
5626:     /* Use a hash table to figure out unique keys */
5627:     PetscCall(PetscHMapICreateWithSize(a->B->cmap->n, &hamp));
5628:     PetscCall(PetscCalloc1(a->B->cmap->n, &mapping));
5629:     count = 0;
5630:     /* Assume that  a->g is sorted, otherwise the following does not make sense */
5631:     for (i = 0; i < a->B->cmap->n; i++) {
5632:       key = a->garray[i] / dof;
5633:       PetscCall(PetscHMapIHas(hamp, key, &has));
5634:       if (!has) {
5635:         mapping[i] = count;
5636:         PetscCall(PetscHMapISet(hamp, key, count++));
5637:       } else {
5638:         /* Current 'i' has the same value the previous step */
5639:         mapping[i] = count - 1;
5640:       }
5641:     }
5642:     PetscCall(ISCreateGeneral(comm, a->B->cmap->n, mapping, PETSC_OWN_POINTER, &map));
5643:     PetscCall(PetscHMapIGetSize(hamp, &htsize));
5644:     PetscCheck(htsize == count, comm, PETSC_ERR_ARG_INCOMP, " Size of hash map %" PetscInt_FMT " is inconsistent with count %" PetscInt_FMT, htsize, count);
5645:     PetscCall(PetscCalloc1(htsize, &rowindices));
5646:     off = 0;
5647:     PetscCall(PetscHMapIGetKeys(hamp, &off, rowindices));
5648:     PetscCall(PetscHMapIDestroy(&hamp));
5649:     PetscCall(PetscSortInt(htsize, rowindices));
5650:     PetscCall(ISCreateGeneral(comm, htsize, rowindices, PETSC_OWN_POINTER, &rows));
5651:     /* In case, the matrix was already created but users want to recreate the matrix */
5652:     PetscCall(MatDestroy(P_oth));
5653:     PetscCall(MatCreateSeqSubMatrixWithRows_Private(P, rows, P_oth));
5654:     PetscCall(PetscObjectCompose((PetscObject)*P_oth, "aoffdiagtopothmapping", (PetscObject)map));
5655:     PetscCall(ISDestroy(&map));
5656:     PetscCall(ISDestroy(&rows));
5657:   } else if (reuse == MAT_REUSE_MATRIX) {
5658:     /* If matrix was already created, we simply update values using SF objects
5659:      * that as attached to the matrix earlier.
5660:      */
5661:     const PetscScalar *pd_a, *po_a;

5663:     PetscCall(PetscObjectQuery((PetscObject)*P_oth, "diagsf", (PetscObject *)&sf));
5664:     PetscCall(PetscObjectQuery((PetscObject)*P_oth, "offdiagsf", (PetscObject *)&osf));
5665:     PetscCheck(sf && osf, comm, PETSC_ERR_ARG_NULL, "Matrix is not initialized yet");
5666:     p_oth = (Mat_SeqAIJ *)(*P_oth)->data;
5667:     /* Update values in place */
5668:     PetscCall(MatSeqAIJGetArrayRead(p->A, &pd_a));
5669:     PetscCall(MatSeqAIJGetArrayRead(p->B, &po_a));
5670:     PetscCall(PetscSFBcastBegin(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5671:     PetscCall(PetscSFBcastBegin(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5672:     PetscCall(PetscSFBcastEnd(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5673:     PetscCall(PetscSFBcastEnd(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5674:     PetscCall(MatSeqAIJRestoreArrayRead(p->A, &pd_a));
5675:     PetscCall(MatSeqAIJRestoreArrayRead(p->B, &po_a));
5676:   } else SETERRQ(comm, PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown reuse type");
5677:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAocols, A, P, 0, 0));
5678:   PetscFunctionReturn(PETSC_SUCCESS);
5679: }

5681: /*@C
5682:   MatGetBrowsOfAcols - Returns `IS` that contain rows of `B` that equal to nonzero columns of local `A`

5684:   Collective

5686:   Input Parameters:
5687: + A     - the first matrix in `MATMPIAIJ` format
5688: . B     - the second matrix in `MATMPIAIJ` format
5689: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5691:   Output Parameters:
5692: + rowb  - On input index sets of rows of B to extract (or `NULL`), modified on output
5693: . colb  - On input index sets of columns of B to extract (or `NULL`), modified on output
5694: - B_seq - the sequential matrix generated

5696:   Level: developer

5698: .seealso: `Mat`, `MATMPIAIJ`, `IS`, `MatReuse`
5699: @*/
5700: PetscErrorCode MatGetBrowsOfAcols(Mat A, Mat B, MatReuse scall, IS *rowb, IS *colb, Mat *B_seq)
5701: {
5702:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
5703:   PetscInt   *idx, i, start, ncols, nzA, nzB, *cmap, imark;
5704:   IS          isrowb, iscolb;
5705:   Mat        *bseq = NULL;

5707:   PetscFunctionBegin;
5708:   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 ")",
5709:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
5710:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAcols, A, B, 0, 0));

5712:   if (scall == MAT_INITIAL_MATRIX) {
5713:     start = A->cmap->rstart;
5714:     cmap  = a->garray;
5715:     nzA   = a->A->cmap->n;
5716:     nzB   = a->B->cmap->n;
5717:     PetscCall(PetscMalloc1(nzA + nzB, &idx));
5718:     ncols = 0;
5719:     for (i = 0; i < nzB; i++) { /* row < local row index */
5720:       if (cmap[i] < start) idx[ncols++] = cmap[i];
5721:       else break;
5722:     }
5723:     imark = i;
5724:     for (i = 0; i < nzA; i++) idx[ncols++] = start + i;   /* local rows */
5725:     for (i = imark; i < nzB; i++) idx[ncols++] = cmap[i]; /* row > local row index */
5726:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, &isrowb));
5727:     PetscCall(ISCreateStride(PETSC_COMM_SELF, B->cmap->N, 0, 1, &iscolb));
5728:   } else {
5729:     PetscCheck(rowb && colb, PETSC_COMM_SELF, PETSC_ERR_SUP, "IS rowb and colb must be provided for MAT_REUSE_MATRIX");
5730:     isrowb = *rowb;
5731:     iscolb = *colb;
5732:     PetscCall(PetscMalloc1(1, &bseq));
5733:     bseq[0] = *B_seq;
5734:   }
5735:   PetscCall(MatCreateSubMatrices(B, 1, &isrowb, &iscolb, scall, &bseq));
5736:   *B_seq = bseq[0];
5737:   PetscCall(PetscFree(bseq));
5738:   if (!rowb) {
5739:     PetscCall(ISDestroy(&isrowb));
5740:   } else {
5741:     *rowb = isrowb;
5742:   }
5743:   if (!colb) {
5744:     PetscCall(ISDestroy(&iscolb));
5745:   } else {
5746:     *colb = iscolb;
5747:   }
5748:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAcols, A, B, 0, 0));
5749:   PetscFunctionReturn(PETSC_SUCCESS);
5750: }

5752: /*
5753:     MatGetBrowsOfAoCols_MPIAIJ - Creates a `MATSEQAIJ` matrix by taking rows of B that equal to nonzero columns
5754:     of the OFF-DIAGONAL portion of local A

5756:     Collective

5758:    Input Parameters:
5759: +    A,B - the matrices in `MATMPIAIJ` format
5760: -    scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5762:    Output Parameter:
5763: +    startsj_s - starting point in B's sending j-arrays, saved for MAT_REUSE (or NULL)
5764: .    startsj_r - starting point in B's receiving j-arrays, saved for MAT_REUSE (or NULL)
5765: .    bufa_ptr - array for sending matrix values, saved for MAT_REUSE (or NULL)
5766: -    B_oth - the sequential matrix generated with size aBn=a->B->cmap->n by B->cmap->N

5768:     Developer Note:
5769:     This directly accesses information inside the VecScatter associated with the matrix-vector product
5770:      for this matrix. This is not desirable..

5772:     Level: developer

5774: */

5776: PetscErrorCode MatGetBrowsOfAoCols_MPIAIJ(Mat A, Mat B, MatReuse scall, PetscInt **startsj_s, PetscInt **startsj_r, MatScalar **bufa_ptr, Mat *B_oth)
5777: {
5778:   Mat_MPIAIJ        *a = (Mat_MPIAIJ *)A->data;
5779:   VecScatter         ctx;
5780:   MPI_Comm           comm;
5781:   const PetscMPIInt *rprocs, *sprocs;
5782:   PetscMPIInt        nrecvs, nsends;
5783:   const PetscInt    *srow, *rstarts, *sstarts;
5784:   PetscInt          *rowlen, *bufj, *bufJ, ncols = 0, aBn = a->B->cmap->n, row, *b_othi, *b_othj, *rvalues = NULL, *svalues = NULL, *cols, sbs, rbs;
5785:   PetscInt           i, j, k = 0, l, ll, nrows, *rstartsj = NULL, *sstartsj, len;
5786:   PetscScalar       *b_otha, *bufa, *bufA, *vals = NULL;
5787:   MPI_Request       *reqs = NULL, *rwaits = NULL, *swaits = NULL;
5788:   PetscMPIInt        size, tag, rank, nreqs;

5790:   PetscFunctionBegin;
5791:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
5792:   PetscCallMPI(MPI_Comm_size(comm, &size));

5794:   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 ")",
5795:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
5796:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAocols, A, B, 0, 0));
5797:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

5799:   if (size == 1) {
5800:     startsj_s = NULL;
5801:     bufa_ptr  = NULL;
5802:     *B_oth    = NULL;
5803:     PetscFunctionReturn(PETSC_SUCCESS);
5804:   }

5806:   ctx = a->Mvctx;
5807:   tag = ((PetscObject)ctx)->tag;

5809:   PetscCall(VecScatterGetRemote_Private(ctx, PETSC_TRUE /*send*/, &nsends, &sstarts, &srow, &sprocs, &sbs));
5810:   /* rprocs[] must be ordered so that indices received from them are ordered in rvalues[], which is key to algorithms used in this subroutine */
5811:   PetscCall(VecScatterGetRemoteOrdered_Private(ctx, PETSC_FALSE /*recv*/, &nrecvs, &rstarts, NULL /*indices not needed*/, &rprocs, &rbs));
5812:   PetscCall(PetscMPIIntCast(nsends + nrecvs, &nreqs));
5813:   PetscCall(PetscMalloc1(nreqs, &reqs));
5814:   rwaits = reqs;
5815:   swaits = PetscSafePointerPlusOffset(reqs, nrecvs);

5817:   if (!startsj_s || !bufa_ptr) scall = MAT_INITIAL_MATRIX;
5818:   if (scall == MAT_INITIAL_MATRIX) {
5819:     /* i-array */
5820:     /*  post receives */
5821:     if (nrecvs) PetscCall(PetscMalloc1(rbs * (rstarts[nrecvs] - rstarts[0]), &rvalues)); /* rstarts can be NULL when nrecvs=0 */
5822:     for (i = 0; i < nrecvs; i++) {
5823:       rowlen = rvalues + rstarts[i] * rbs;
5824:       nrows  = (rstarts[i + 1] - rstarts[i]) * rbs; /* num of indices to be received */
5825:       PetscCallMPI(MPIU_Irecv(rowlen, nrows, MPIU_INT, rprocs[i], tag, comm, rwaits + i));
5826:     }

5828:     /* pack the outgoing message */
5829:     PetscCall(PetscMalloc2(nsends + 1, &sstartsj, nrecvs + 1, &rstartsj));

5831:     sstartsj[0] = 0;
5832:     rstartsj[0] = 0;
5833:     len         = 0; /* total length of j or a array to be sent */
5834:     if (nsends) {
5835:       k = sstarts[0]; /* ATTENTION: sstarts[0] and rstarts[0] are not necessarily zero */
5836:       PetscCall(PetscMalloc1(sbs * (sstarts[nsends] - sstarts[0]), &svalues));
5837:     }
5838:     for (i = 0; i < nsends; i++) {
5839:       rowlen = svalues + (sstarts[i] - sstarts[0]) * sbs;
5840:       nrows  = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5841:       for (j = 0; j < nrows; j++) {
5842:         row = srow[k] + B->rmap->range[rank]; /* global row idx */
5843:         for (l = 0; l < sbs; l++) {
5844:           PetscCall(MatGetRow_MPIAIJ(B, row + l, &ncols, NULL, NULL)); /* rowlength */

5846:           rowlen[j * sbs + l] = ncols;

5848:           len += ncols;
5849:           PetscCall(MatRestoreRow_MPIAIJ(B, row + l, &ncols, NULL, NULL));
5850:         }
5851:         k++;
5852:       }
5853:       PetscCallMPI(MPIU_Isend(rowlen, nrows * sbs, MPIU_INT, sprocs[i], tag, comm, swaits + i));

5855:       sstartsj[i + 1] = len; /* starting point of (i+1)-th outgoing msg in bufj and bufa */
5856:     }
5857:     /* recvs and sends of i-array are completed */
5858:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5859:     PetscCall(PetscFree(svalues));

5861:     /* allocate buffers for sending j and a arrays */
5862:     PetscCall(PetscMalloc1(len + 1, &bufj));
5863:     PetscCall(PetscMalloc1(len + 1, &bufa));

5865:     /* create i-array of B_oth */
5866:     PetscCall(PetscMalloc1(aBn + 2, &b_othi));

5868:     b_othi[0] = 0;
5869:     len       = 0; /* total length of j or a array to be received */
5870:     k         = 0;
5871:     for (i = 0; i < nrecvs; i++) {
5872:       rowlen = rvalues + (rstarts[i] - rstarts[0]) * rbs;
5873:       nrows  = (rstarts[i + 1] - rstarts[i]) * rbs; /* num of rows to be received */
5874:       for (j = 0; j < nrows; j++) {
5875:         b_othi[k + 1] = b_othi[k] + rowlen[j];
5876:         PetscCall(PetscIntSumError(rowlen[j], len, &len));
5877:         k++;
5878:       }
5879:       rstartsj[i + 1] = len; /* starting point of (i+1)-th incoming msg in bufj and bufa */
5880:     }
5881:     PetscCall(PetscFree(rvalues));

5883:     /* allocate space for j and a arrays of B_oth */
5884:     PetscCall(PetscMalloc1(b_othi[aBn] + 1, &b_othj));
5885:     PetscCall(PetscMalloc1(b_othi[aBn] + 1, &b_otha));

5887:     /* j-array */
5888:     /*  post receives of j-array */
5889:     for (i = 0; i < nrecvs; i++) {
5890:       nrows = rstartsj[i + 1] - rstartsj[i]; /* length of the msg received */
5891:       PetscCallMPI(MPIU_Irecv(b_othj + rstartsj[i], nrows, MPIU_INT, rprocs[i], tag, comm, rwaits + i));
5892:     }

5894:     /* pack the outgoing message j-array */
5895:     if (nsends) k = sstarts[0];
5896:     for (i = 0; i < nsends; i++) {
5897:       nrows = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5898:       bufJ  = bufj + sstartsj[i];
5899:       for (j = 0; j < nrows; j++) {
5900:         row = srow[k++] + B->rmap->range[rank]; /* global row idx */
5901:         for (ll = 0; ll < sbs; ll++) {
5902:           PetscCall(MatGetRow_MPIAIJ(B, row + ll, &ncols, &cols, NULL));
5903:           for (l = 0; l < ncols; l++) *bufJ++ = cols[l];
5904:           PetscCall(MatRestoreRow_MPIAIJ(B, row + ll, &ncols, &cols, NULL));
5905:         }
5906:       }
5907:       PetscCallMPI(MPIU_Isend(bufj + sstartsj[i], sstartsj[i + 1] - sstartsj[i], MPIU_INT, sprocs[i], tag, comm, swaits + i));
5908:     }

5910:     /* recvs and sends of j-array are completed */
5911:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5912:   } else if (scall == MAT_REUSE_MATRIX) {
5913:     sstartsj = *startsj_s;
5914:     rstartsj = *startsj_r;
5915:     bufa     = *bufa_ptr;
5916:     PetscCall(MatSeqAIJGetArrayWrite(*B_oth, &b_otha));
5917:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Matrix P does not possess an object container");

5919:   /* a-array */
5920:   /*  post receives of a-array */
5921:   for (i = 0; i < nrecvs; i++) {
5922:     nrows = rstartsj[i + 1] - rstartsj[i]; /* length of the msg received */
5923:     PetscCallMPI(MPIU_Irecv(b_otha + rstartsj[i], nrows, MPIU_SCALAR, rprocs[i], tag, comm, rwaits + i));
5924:   }

5926:   /* pack the outgoing message a-array */
5927:   if (nsends) k = sstarts[0];
5928:   for (i = 0; i < nsends; i++) {
5929:     nrows = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5930:     bufA  = bufa + sstartsj[i];
5931:     for (j = 0; j < nrows; j++) {
5932:       row = srow[k++] + B->rmap->range[rank]; /* global row idx */
5933:       for (ll = 0; ll < sbs; ll++) {
5934:         PetscCall(MatGetRow_MPIAIJ(B, row + ll, &ncols, NULL, &vals));
5935:         for (l = 0; l < ncols; l++) *bufA++ = vals[l];
5936:         PetscCall(MatRestoreRow_MPIAIJ(B, row + ll, &ncols, NULL, &vals));
5937:       }
5938:     }
5939:     PetscCallMPI(MPIU_Isend(bufa + sstartsj[i], sstartsj[i + 1] - sstartsj[i], MPIU_SCALAR, sprocs[i], tag, comm, swaits + i));
5940:   }
5941:   /* recvs and sends of a-array are completed */
5942:   if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5943:   PetscCall(PetscFree(reqs));

5945:   if (scall == MAT_INITIAL_MATRIX) {
5946:     Mat_SeqAIJ *b_oth;

5948:     /* put together the new matrix */
5949:     PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, aBn, B->cmap->N, b_othi, b_othj, b_otha, B_oth));

5951:     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5952:     /* Since these are PETSc arrays, change flags to free them as necessary. */
5953:     b_oth          = (Mat_SeqAIJ *)(*B_oth)->data;
5954:     b_oth->free_a  = PETSC_TRUE;
5955:     b_oth->free_ij = PETSC_TRUE;
5956:     b_oth->nonew   = 0;

5958:     PetscCall(PetscFree(bufj));
5959:     if (!startsj_s || !bufa_ptr) {
5960:       PetscCall(PetscFree2(sstartsj, rstartsj));
5961:       PetscCall(PetscFree(bufa_ptr));
5962:     } else {
5963:       *startsj_s = sstartsj;
5964:       *startsj_r = rstartsj;
5965:       *bufa_ptr  = bufa;
5966:     }
5967:   } else if (scall == MAT_REUSE_MATRIX) {
5968:     PetscCall(MatSeqAIJRestoreArrayWrite(*B_oth, &b_otha));
5969:   }

5971:   PetscCall(VecScatterRestoreRemote_Private(ctx, PETSC_TRUE, &nsends, &sstarts, &srow, &sprocs, &sbs));
5972:   PetscCall(VecScatterRestoreRemoteOrdered_Private(ctx, PETSC_FALSE, &nrecvs, &rstarts, NULL, &rprocs, &rbs));
5973:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAocols, A, B, 0, 0));
5974:   PetscFunctionReturn(PETSC_SUCCESS);
5975: }

5977: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCRL(Mat, MatType, MatReuse, Mat *);
5978: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJPERM(Mat, MatType, MatReuse, Mat *);
5979: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJSELL(Mat, MatType, MatReuse, Mat *);
5980: #if defined(PETSC_HAVE_MKL_SPARSE)
5981: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJMKL(Mat, MatType, MatReuse, Mat *);
5982: #endif
5983: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIBAIJ(Mat, MatType, MatReuse, Mat *);
5984: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPISBAIJ(Mat, MatType, MatReuse, Mat *);
5985: #if defined(PETSC_HAVE_ELEMENTAL)
5986: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_Elemental(Mat, MatType, MatReuse, Mat *);
5987: #endif
5988: #if defined(PETSC_HAVE_SCALAPACK)
5989: PETSC_INTERN PetscErrorCode MatConvert_AIJ_ScaLAPACK(Mat, MatType, MatReuse, Mat *);
5990: #endif
5991: #if defined(PETSC_HAVE_HYPRE)
5992: PETSC_INTERN PetscErrorCode MatConvert_AIJ_HYPRE(Mat, MatType, MatReuse, Mat *);
5993: #endif
5994: #if defined(PETSC_HAVE_CUDA)
5995: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCUSPARSE(Mat, MatType, MatReuse, Mat *);
5996: #endif
5997: #if defined(PETSC_HAVE_HIP)
5998: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJHIPSPARSE(Mat, MatType, MatReuse, Mat *);
5999: #endif
6000: #if defined(PETSC_HAVE_KOKKOS_KERNELS)
6001: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJKokkos(Mat, MatType, MatReuse, Mat *);
6002: #endif
6003: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPISELL(Mat, MatType, MatReuse, Mat *);
6004: PETSC_INTERN PetscErrorCode MatConvert_XAIJ_IS(Mat, MatType, MatReuse, Mat *);
6005: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_IS_XAIJ(Mat);

6007: /*
6008:     Computes (B'*A')' since computing B*A directly is untenable

6010:                n                       p                          p
6011:         [             ]       [             ]         [                 ]
6012:       m [      A      ]  *  n [       B     ]   =   m [         C       ]
6013:         [             ]       [             ]         [                 ]

6015: */
6016: static PetscErrorCode MatMatMultNumeric_MPIDense_MPIAIJ(Mat A, Mat B, Mat C)
6017: {
6018:   Mat At, Bt, Ct;

6020:   PetscFunctionBegin;
6021:   PetscCall(MatTranspose(A, MAT_INITIAL_MATRIX, &At));
6022:   PetscCall(MatTranspose(B, MAT_INITIAL_MATRIX, &Bt));
6023:   PetscCall(MatMatMult(Bt, At, MAT_INITIAL_MATRIX, PETSC_CURRENT, &Ct));
6024:   PetscCall(MatDestroy(&At));
6025:   PetscCall(MatDestroy(&Bt));
6026:   PetscCall(MatTransposeSetPrecursor(Ct, C));
6027:   PetscCall(MatTranspose(Ct, MAT_REUSE_MATRIX, &C));
6028:   PetscCall(MatDestroy(&Ct));
6029:   PetscFunctionReturn(PETSC_SUCCESS);
6030: }

6032: static PetscErrorCode MatMatMultSymbolic_MPIDense_MPIAIJ(Mat A, Mat B, PetscReal fill, Mat C)
6033: {
6034:   PetscBool cisdense;

6036:   PetscFunctionBegin;
6037:   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);
6038:   PetscCall(MatSetSizes(C, A->rmap->n, B->cmap->n, A->rmap->N, B->cmap->N));
6039:   PetscCall(MatSetBlockSizesFromMats(C, A, B));
6040:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &cisdense, MATMPIDENSE, MATMPIDENSECUDA, MATMPIDENSEHIP, ""));
6041:   if (!cisdense) PetscCall(MatSetType(C, ((PetscObject)A)->type_name));
6042:   PetscCall(MatSetUp(C));

6044:   C->ops->matmultnumeric = MatMatMultNumeric_MPIDense_MPIAIJ;
6045:   PetscFunctionReturn(PETSC_SUCCESS);
6046: }

6048: static PetscErrorCode MatProductSetFromOptions_MPIDense_MPIAIJ_AB(Mat C)
6049: {
6050:   Mat_Product *product = C->product;
6051:   Mat          A = product->A, B = product->B;

6053:   PetscFunctionBegin;
6054:   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 ")",
6055:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
6056:   C->ops->matmultsymbolic = MatMatMultSymbolic_MPIDense_MPIAIJ;
6057:   C->ops->productsymbolic = MatProductSymbolic_AB;
6058:   PetscFunctionReturn(PETSC_SUCCESS);
6059: }

6061: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_MPIDense_MPIAIJ(Mat C)
6062: {
6063:   Mat_Product *product = C->product;

6065:   PetscFunctionBegin;
6066:   if (product->type == MATPRODUCT_AB) PetscCall(MatProductSetFromOptions_MPIDense_MPIAIJ_AB(C));
6067:   PetscFunctionReturn(PETSC_SUCCESS);
6068: }

6070: /*
6071:    Merge two sets of sorted nonzeros and return a CSR for the merged (sequential) matrix

6073:   Input Parameters:

6075:     j1,rowBegin1,rowEnd1,jmap1: describe the first set of nonzeros (Set1)
6076:     j2,rowBegin2,rowEnd2,jmap2: describe the second set of nonzeros (Set2)

6078:     mat: both sets' nonzeros are on m rows, where m is the number of local rows of the matrix mat

6080:     For Set1, j1[] contains column indices of the nonzeros.
6081:     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
6082:     respectively (note rowEnd1[k] is not necessarily equal to rwoBegin1[k+1]). Indices in this range of j1[] are sorted,
6083:     but might have repeats. jmap1[t+1] - jmap1[t] is the number of repeats for the t-th unique nonzero in Set1.

6085:     Similar for Set2.

6087:     This routine merges the two sets of nonzeros row by row and removes repeats.

6089:   Output Parameters: (memory is allocated by the caller)

6091:     i[],j[]: the CSR of the merged matrix, which has m rows.
6092:     imap1[]: the k-th unique nonzero in Set1 (k=0,1,...) corresponds to imap1[k]-th unique nonzero in the merged matrix.
6093:     imap2[]: similar to imap1[], but for Set2.
6094:     Note we order nonzeros row-by-row and from left to right.
6095: */
6096: 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[])
6097: {
6098:   PetscInt   r, m; /* Row index of mat */
6099:   PetscCount t, t1, t2, b1, e1, b2, e2;

6101:   PetscFunctionBegin;
6102:   PetscCall(MatGetLocalSize(mat, &m, NULL));
6103:   t1 = t2 = t = 0; /* Count unique nonzeros of in Set1, Set1 and the merged respectively */
6104:   i[0]        = 0;
6105:   for (r = 0; r < m; r++) { /* Do row by row merging */
6106:     b1 = rowBegin1[r];
6107:     e1 = rowEnd1[r];
6108:     b2 = rowBegin2[r];
6109:     e2 = rowEnd2[r];
6110:     while (b1 < e1 && b2 < e2) {
6111:       if (j1[b1] == j2[b2]) { /* Same column index and hence same nonzero */
6112:         j[t]      = j1[b1];
6113:         imap1[t1] = t;
6114:         imap2[t2] = t;
6115:         b1 += jmap1[t1 + 1] - jmap1[t1]; /* Jump to next unique local nonzero */
6116:         b2 += jmap2[t2 + 1] - jmap2[t2]; /* Jump to next unique remote nonzero */
6117:         t1++;
6118:         t2++;
6119:         t++;
6120:       } else if (j1[b1] < j2[b2]) {
6121:         j[t]      = j1[b1];
6122:         imap1[t1] = t;
6123:         b1 += jmap1[t1 + 1] - jmap1[t1];
6124:         t1++;
6125:         t++;
6126:       } else {
6127:         j[t]      = j2[b2];
6128:         imap2[t2] = t;
6129:         b2 += jmap2[t2 + 1] - jmap2[t2];
6130:         t2++;
6131:         t++;
6132:       }
6133:     }
6134:     /* Merge the remaining in either j1[] or j2[] */
6135:     while (b1 < e1) {
6136:       j[t]      = j1[b1];
6137:       imap1[t1] = t;
6138:       b1 += jmap1[t1 + 1] - jmap1[t1];
6139:       t1++;
6140:       t++;
6141:     }
6142:     while (b2 < e2) {
6143:       j[t]      = j2[b2];
6144:       imap2[t2] = t;
6145:       b2 += jmap2[t2 + 1] - jmap2[t2];
6146:       t2++;
6147:       t++;
6148:     }
6149:     PetscCall(PetscIntCast(t, i + r + 1));
6150:   }
6151:   PetscFunctionReturn(PETSC_SUCCESS);
6152: }

6154: /*
6155:   Split nonzeros in a block of local rows into two subsets: those in the diagonal block and those in the off-diagonal block

6157:   Input Parameters:
6158:     mat: an MPI matrix that provides row and column layout information for splitting. Let's say its number of local rows is m.
6159:     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[]
6160:       respectively, along with a permutation array perm[]. Length of the i[],j[],perm[] arrays is n.

6162:       i[] is already sorted, but within a row, j[] is not sorted and might have repeats.
6163:       i[] might contain negative indices at the beginning, which means the corresponding entries should be ignored in the splitting.

6165:   Output Parameters:
6166:     j[],perm[]: the routine needs to sort j[] within each row along with perm[].
6167:     rowBegin[],rowMid[],rowEnd[]: of length m, and the memory is preallocated and zeroed by the caller.
6168:       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,
6169:       and [rowMid[r],rowEnd[r]) point to begin/end entries of row r of the off-diagonal block.

6171:     Aperm[],Ajmap[],Atot,Annz: Arrays are allocated by this routine.
6172:       Atot: number of entries belonging to the diagonal block.
6173:       Annz: number of unique nonzeros belonging to the diagonal block.
6174:       Aperm[Atot] stores values from perm[] for entries belonging to the diagonal block. Length of Aperm[] is Atot, though it may also count
6175:         repeats (i.e., same 'i,j' pair).
6176:       Ajmap[Annz+1] stores the number of repeats of each unique entry belonging to the diagonal block. More precisely, Ajmap[t+1] - Ajmap[t]
6177:         is the number of repeats for the t-th unique entry in the diagonal block. Ajmap[0] is always 0.

6179:       Atot: number of entries belonging to the diagonal block
6180:       Annz: number of unique nonzeros belonging to the diagonal block.

6182:     Bperm[], Bjmap[], Btot, Bnnz are similar but for the off-diagonal block.

6184:     Aperm[],Bperm[],Ajmap[] and Bjmap[] are allocated separately by this routine with PetscMalloc1().
6185: */
6186: 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_)
6187: {
6188:   PetscInt    cstart, cend, rstart, rend, row, col;
6189:   PetscCount  Atot = 0, Btot = 0; /* Total number of nonzeros in the diagonal and off-diagonal blocks */
6190:   PetscCount  Annz = 0, Bnnz = 0; /* Number of unique nonzeros in the diagonal and off-diagonal blocks */
6191:   PetscCount  k, m, p, q, r, s, mid;
6192:   PetscCount *Aperm, *Bperm, *Ajmap, *Bjmap;

6194:   PetscFunctionBegin;
6195:   PetscCall(PetscLayoutGetRange(mat->rmap, &rstart, &rend));
6196:   PetscCall(PetscLayoutGetRange(mat->cmap, &cstart, &cend));
6197:   m = rend - rstart;

6199:   /* Skip negative rows */
6200:   for (k = 0; k < n; k++)
6201:     if (i[k] >= 0) break;

6203:   /* Process [k,n): sort and partition each local row into diag and offdiag portions,
6204:      fill rowBegin[], rowMid[], rowEnd[], and count Atot, Btot, Annz, Bnnz.
6205:   */
6206:   while (k < n) {
6207:     row = i[k];
6208:     /* Entries in [k,s) are in one row. Shift diagonal block col indices so that diag is ahead of offdiag after sorting the row */
6209:     for (s = k; s < n; s++)
6210:       if (i[s] != row) break;

6212:     /* Shift diag columns to range of [-PETSC_INT_MAX, -1] */
6213:     for (p = k; p < s; p++) {
6214:       if (j[p] >= cstart && j[p] < cend) j[p] -= PETSC_INT_MAX;
6215:     }
6216:     PetscCall(PetscSortIntWithCountArray(s - k, j + k, perm + k));
6217:     PetscCall(PetscSortedIntUpperBound(j, k, s, -1, &mid)); /* Separate [k,s) into [k,mid) for diag and [mid,s) for offdiag */
6218:     rowBegin[row - rstart] = k;
6219:     rowMid[row - rstart]   = mid;
6220:     rowEnd[row - rstart]   = s;
6221:     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);

6223:     /* Count nonzeros of this diag/offdiag row, which might have repeats */
6224:     Atot += mid - k;
6225:     Btot += s - mid;

6227:     /* Count unique nonzeros of this diag row */
6228:     for (p = k; p < mid;) {
6229:       col = j[p];
6230:       do {
6231:         j[p] += PETSC_INT_MAX; /* Revert the modified diagonal indices */
6232:         p++;
6233:       } while (p < mid && j[p] == col);
6234:       Annz++;
6235:     }

6237:     /* Count unique nonzeros of this offdiag row */
6238:     for (p = mid; p < s;) {
6239:       col = j[p];
6240:       do {
6241:         p++;
6242:       } while (p < s && j[p] == col);
6243:       Bnnz++;
6244:     }
6245:     k = s;
6246:   }

6248:   /* Allocation according to Atot, Btot, Annz, Bnnz */
6249:   PetscCall(PetscMalloc1(Atot, &Aperm));
6250:   PetscCall(PetscMalloc1(Btot, &Bperm));
6251:   PetscCall(PetscMalloc1(Annz + 1, &Ajmap));
6252:   PetscCall(PetscMalloc1(Bnnz + 1, &Bjmap));

6254:   /* Re-scan indices and copy diag/offdiag permutation indices to Aperm, Bperm and also fill Ajmap and Bjmap */
6255:   Ajmap[0] = Bjmap[0] = Atot = Btot = Annz = Bnnz = 0;
6256:   for (r = 0; r < m; r++) {
6257:     k   = rowBegin[r];
6258:     mid = rowMid[r];
6259:     s   = rowEnd[r];
6260:     PetscCall(PetscArraycpy(PetscSafePointerPlusOffset(Aperm, Atot), PetscSafePointerPlusOffset(perm, k), mid - k));
6261:     PetscCall(PetscArraycpy(PetscSafePointerPlusOffset(Bperm, Btot), PetscSafePointerPlusOffset(perm, mid), s - mid));
6262:     Atot += mid - k;
6263:     Btot += s - mid;

6265:     /* Scan column indices in this row and find out how many repeats each unique nonzero has */
6266:     for (p = k; p < mid;) {
6267:       col = j[p];
6268:       q   = p;
6269:       do {
6270:         p++;
6271:       } while (p < mid && j[p] == col);
6272:       Ajmap[Annz + 1] = Ajmap[Annz] + (p - q);
6273:       Annz++;
6274:     }

6276:     for (p = mid; p < s;) {
6277:       col = j[p];
6278:       q   = p;
6279:       do {
6280:         p++;
6281:       } while (p < s && j[p] == col);
6282:       Bjmap[Bnnz + 1] = Bjmap[Bnnz] + (p - q);
6283:       Bnnz++;
6284:     }
6285:   }
6286:   /* Output */
6287:   *Aperm_ = Aperm;
6288:   *Annz_  = Annz;
6289:   *Atot_  = Atot;
6290:   *Ajmap_ = Ajmap;
6291:   *Bperm_ = Bperm;
6292:   *Bnnz_  = Bnnz;
6293:   *Btot_  = Btot;
6294:   *Bjmap_ = Bjmap;
6295:   PetscFunctionReturn(PETSC_SUCCESS);
6296: }

6298: /*
6299:   Expand the jmap[] array to make a new one in view of nonzeros in the merged matrix

6301:   Input Parameters:
6302:     nnz1: number of unique nonzeros in a set that was used to produce imap[], jmap[]
6303:     nnz:  number of unique nonzeros in the merged matrix
6304:     imap[nnz1]: i-th nonzero in the set is the imap[i]-th nonzero in the merged matrix
6305:     jmap[nnz1+1]: i-th nonzero in the set has jmap[i+1] - jmap[i] repeats in the set

6307:   Output Parameter: (memory is allocated by the caller)
6308:     jmap_new[nnz+1]: i-th nonzero in the merged matrix has jmap_new[i+1] - jmap_new[i] repeats in the set

6310:   Example:
6311:     nnz1 = 4
6312:     nnz  = 6
6313:     imap = [1,3,4,5]
6314:     jmap = [0,3,5,6,7]
6315:    then,
6316:     jmap_new = [0,0,3,3,5,6,7]
6317: */
6318: static PetscErrorCode ExpandJmap_Internal(PetscCount nnz1, PetscCount nnz, const PetscCount imap[], const PetscCount jmap[], PetscCount jmap_new[])
6319: {
6320:   PetscCount k, p;

6322:   PetscFunctionBegin;
6323:   jmap_new[0] = 0;
6324:   p           = nnz;                /* p loops over jmap_new[] backwards */
6325:   for (k = nnz1 - 1; k >= 0; k--) { /* k loops over imap[] */
6326:     for (; p > imap[k]; p--) jmap_new[p] = jmap[k + 1];
6327:   }
6328:   for (; p >= 0; p--) jmap_new[p] = jmap[0];
6329:   PetscFunctionReturn(PETSC_SUCCESS);
6330: }

6332: static PetscErrorCode MatCOOStructDestroy_MPIAIJ(void **data)
6333: {
6334:   MatCOOStruct_MPIAIJ *coo = (MatCOOStruct_MPIAIJ *)*data;

6336:   PetscFunctionBegin;
6337:   PetscCall(PetscSFDestroy(&coo->sf));
6338:   PetscCall(PetscFree(coo->Aperm1));
6339:   PetscCall(PetscFree(coo->Bperm1));
6340:   PetscCall(PetscFree(coo->Ajmap1));
6341:   PetscCall(PetscFree(coo->Bjmap1));
6342:   PetscCall(PetscFree(coo->Aimap2));
6343:   PetscCall(PetscFree(coo->Bimap2));
6344:   PetscCall(PetscFree(coo->Aperm2));
6345:   PetscCall(PetscFree(coo->Bperm2));
6346:   PetscCall(PetscFree(coo->Ajmap2));
6347:   PetscCall(PetscFree(coo->Bjmap2));
6348:   PetscCall(PetscFree(coo->Cperm1));
6349:   PetscCall(PetscFree2(coo->sendbuf, coo->recvbuf));
6350:   PetscCall(PetscFree(coo));
6351:   PetscFunctionReturn(PETSC_SUCCESS);
6352: }

6354: PetscErrorCode MatSetPreallocationCOO_MPIAIJ(Mat mat, PetscCount coo_n, PetscInt coo_i[], PetscInt coo_j[])
6355: {
6356:   MPI_Comm             comm;
6357:   PetscMPIInt          rank, size;
6358:   PetscInt             m, n, M, N, rstart, rend, cstart, cend; /* Sizes, indices of row/col, therefore with type PetscInt */
6359:   PetscCount           k, p, q, rem;                           /* Loop variables over coo arrays */
6360:   Mat_MPIAIJ          *mpiaij = (Mat_MPIAIJ *)mat->data;
6361:   PetscContainer       container;
6362:   MatCOOStruct_MPIAIJ *coo;

6364:   PetscFunctionBegin;
6365:   PetscCall(PetscFree(mpiaij->garray));
6366:   PetscCall(VecDestroy(&mpiaij->lvec));
6367: #if defined(PETSC_USE_CTABLE)
6368:   PetscCall(PetscHMapIDestroy(&mpiaij->colmap));
6369: #else
6370:   PetscCall(PetscFree(mpiaij->colmap));
6371: #endif
6372:   PetscCall(VecScatterDestroy(&mpiaij->Mvctx));
6373:   mat->assembled     = PETSC_FALSE;
6374:   mat->was_assembled = PETSC_FALSE;

6376:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
6377:   PetscCallMPI(MPI_Comm_size(comm, &size));
6378:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
6379:   PetscCall(PetscLayoutSetUp(mat->rmap));
6380:   PetscCall(PetscLayoutSetUp(mat->cmap));
6381:   PetscCall(PetscLayoutGetRange(mat->rmap, &rstart, &rend));
6382:   PetscCall(PetscLayoutGetRange(mat->cmap, &cstart, &cend));
6383:   PetscCall(MatGetLocalSize(mat, &m, &n));
6384:   PetscCall(MatGetSize(mat, &M, &N));

6386:   /* Sort (i,j) by row along with a permutation array, so that the to-be-ignored */
6387:   /* entries come first, then local rows, then remote rows.                     */
6388:   PetscCount n1 = coo_n, *perm1;
6389:   PetscInt  *i1 = coo_i, *j1 = coo_j;

6391:   PetscCall(PetscMalloc1(n1, &perm1));
6392:   for (k = 0; k < n1; k++) perm1[k] = k;

6394:   /* Manipulate indices so that entries with negative row or col indices will have smallest
6395:      row indices, local entries will have greater but negative row indices, and remote entries
6396:      will have positive row indices.
6397:   */
6398:   for (k = 0; k < n1; k++) {
6399:     if (i1[k] < 0 || j1[k] < 0) i1[k] = PETSC_INT_MIN;                /* e.g., -2^31, minimal to move them ahead */
6400:     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] */
6401:     else {
6402:       PetscCheck(!mat->nooffprocentries, PETSC_COMM_SELF, PETSC_ERR_USER_INPUT, "MAT_NO_OFF_PROC_ENTRIES is set but insert to remote rows");
6403:       if (mpiaij->donotstash) i1[k] = PETSC_INT_MIN; /* Ignore offproc entries as if they had negative indices */
6404:     }
6405:   }

6407:   /* Sort by row; after that, [0,k) have ignored entries, [k,rem) have local rows and [rem,n1) have remote rows */
6408:   PetscCall(PetscSortIntWithIntCountArrayPair(n1, i1, j1, perm1));

6410:   /* Advance k to the first entry we need to take care of */
6411:   for (k = 0; k < n1; k++)
6412:     if (i1[k] > PETSC_INT_MIN) break;
6413:   PetscCount i1start = k;

6415:   PetscCall(PetscSortedIntUpperBound(i1, k, n1, rend - 1 - PETSC_INT_MAX, &rem)); /* rem is upper bound of the last local row */
6416:   for (; k < rem; k++) i1[k] += PETSC_INT_MAX;                                    /* Revert row indices of local rows*/

6418:   PetscCheck(i1 == NULL || 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);

6420:   /*           Send remote rows to their owner                                  */
6421:   /* Find which rows should be sent to which remote ranks*/
6422:   PetscInt        nsend = 0; /* Number of MPI ranks to send data to */
6423:   PetscMPIInt    *sendto;    /* [nsend], storing remote ranks */
6424:   PetscInt       *nentries;  /* [nsend], storing number of entries sent to remote ranks; Assume PetscInt is big enough for this count, and error if not */
6425:   const PetscInt *ranges;
6426:   PetscInt        maxNsend = size >= 128 ? 128 : size; /* Assume max 128 neighbors; realloc when needed */

6428:   PetscCall(PetscLayoutGetRanges(mat->rmap, &ranges));
6429:   PetscCall(PetscMalloc2(maxNsend, &sendto, maxNsend, &nentries));
6430:   for (k = rem; k < n1;) {
6431:     PetscMPIInt owner;
6432:     PetscInt    firstRow, lastRow;

6434:     /* Locate a row range */
6435:     firstRow = i1[k]; /* first row of this owner */
6436:     PetscCall(PetscLayoutFindOwner(mat->rmap, firstRow, &owner));
6437:     lastRow = ranges[owner + 1] - 1; /* last row of this owner */

6439:     /* Find the first index 'p' in [k,n) with i1[p] belonging to next owner */
6440:     PetscCall(PetscSortedIntUpperBound(i1, k, n1, lastRow, &p));

6442:     /* All entries in [k,p) belong to this remote owner */
6443:     if (nsend >= maxNsend) { /* Double the remote ranks arrays if not long enough */
6444:       PetscMPIInt *sendto2;
6445:       PetscInt    *nentries2;
6446:       PetscInt     maxNsend2 = (maxNsend <= size / 2) ? maxNsend * 2 : size;

6448:       PetscCall(PetscMalloc2(maxNsend2, &sendto2, maxNsend2, &nentries2));
6449:       PetscCall(PetscArraycpy(sendto2, sendto, maxNsend));
6450:       PetscCall(PetscArraycpy(nentries2, nentries2, maxNsend + 1));
6451:       PetscCall(PetscFree2(sendto, nentries2));
6452:       sendto   = sendto2;
6453:       nentries = nentries2;
6454:       maxNsend = maxNsend2;
6455:     }
6456:     sendto[nsend] = owner;
6457:     PetscCall(PetscIntCast(p - k, &nentries[nsend]));
6458:     nsend++;
6459:     k = p;
6460:   }

6462:   /* Build 1st SF to know offsets on remote to send data */
6463:   PetscSF      sf1;
6464:   PetscInt     nroots = 1, nroots2 = 0;
6465:   PetscInt     nleaves = nsend, nleaves2 = 0;
6466:   PetscInt    *offsets;
6467:   PetscSFNode *iremote;

6469:   PetscCall(PetscSFCreate(comm, &sf1));
6470:   PetscCall(PetscMalloc1(nsend, &iremote));
6471:   PetscCall(PetscMalloc1(nsend, &offsets));
6472:   for (k = 0; k < nsend; k++) {
6473:     iremote[k].rank  = sendto[k];
6474:     iremote[k].index = 0;
6475:     nleaves2 += nentries[k];
6476:     PetscCheck(nleaves2 >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of SF leaves is too large for PetscInt");
6477:   }
6478:   PetscCall(PetscSFSetGraph(sf1, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
6479:   PetscCall(PetscSFFetchAndOpWithMemTypeBegin(sf1, MPIU_INT, PETSC_MEMTYPE_HOST, &nroots2 /*rootdata*/, PETSC_MEMTYPE_HOST, nentries /*leafdata*/, PETSC_MEMTYPE_HOST, offsets /*leafupdate*/, MPI_SUM));
6480:   PetscCall(PetscSFFetchAndOpEnd(sf1, MPIU_INT, &nroots2, nentries, offsets, MPI_SUM)); /* Would nroots2 overflow, we check offsets[] below */
6481:   PetscCall(PetscSFDestroy(&sf1));
6482:   PetscAssert(nleaves2 == n1 - rem, PETSC_COMM_SELF, PETSC_ERR_PLIB, "nleaves2 %" PetscInt_FMT " != number of remote entries %" PetscCount_FMT, nleaves2, n1 - rem);

6484:   /* Build 2nd SF to send remote COOs to their owner */
6485:   PetscSF sf2;
6486:   nroots  = nroots2;
6487:   nleaves = nleaves2;
6488:   PetscCall(PetscSFCreate(comm, &sf2));
6489:   PetscCall(PetscSFSetFromOptions(sf2));
6490:   PetscCall(PetscMalloc1(nleaves, &iremote));
6491:   p = 0;
6492:   for (k = 0; k < nsend; k++) {
6493:     PetscCheck(offsets[k] >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of SF roots is too large for PetscInt");
6494:     for (q = 0; q < nentries[k]; q++, p++) {
6495:       iremote[p].rank = sendto[k];
6496:       PetscCall(PetscIntCast(offsets[k] + q, &iremote[p].index));
6497:     }
6498:   }
6499:   PetscCall(PetscSFSetGraph(sf2, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));

6501:   /* Send the remote COOs to their owner */
6502:   PetscInt    n2 = nroots, *i2, *j2; /* Buffers for received COOs from other ranks, along with a permutation array */
6503:   PetscCount *perm2;                 /* Though PetscInt is enough for remote entries, we use PetscCount here as we want to reuse MatSplitEntries_Internal() */
6504:   PetscCall(PetscMalloc3(n2, &i2, n2, &j2, n2, &perm2));
6505:   PetscAssert(rem == 0 || i1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6506:   PetscAssert(rem == 0 || j1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6507:   PetscInt *i1prem = PetscSafePointerPlusOffset(i1, rem);
6508:   PetscInt *j1prem = PetscSafePointerPlusOffset(j1, rem);
6509:   PetscCall(PetscSFReduceWithMemTypeBegin(sf2, MPIU_INT, PETSC_MEMTYPE_HOST, i1prem, PETSC_MEMTYPE_HOST, i2, MPI_REPLACE));
6510:   PetscCall(PetscSFReduceEnd(sf2, MPIU_INT, i1prem, i2, MPI_REPLACE));
6511:   PetscCall(PetscSFReduceWithMemTypeBegin(sf2, MPIU_INT, PETSC_MEMTYPE_HOST, j1prem, PETSC_MEMTYPE_HOST, j2, MPI_REPLACE));
6512:   PetscCall(PetscSFReduceEnd(sf2, MPIU_INT, j1prem, j2, MPI_REPLACE));

6514:   PetscCall(PetscFree(offsets));
6515:   PetscCall(PetscFree2(sendto, nentries));

6517:   /* Sort received COOs by row along with the permutation array     */
6518:   for (k = 0; k < n2; k++) perm2[k] = k;
6519:   PetscCall(PetscSortIntWithIntCountArrayPair(n2, i2, j2, perm2));

6521:   /* sf2 only sends contiguous leafdata to contiguous rootdata. We record the permutation which will be used to fill leafdata */
6522:   PetscCount *Cperm1;
6523:   PetscAssert(rem == 0 || perm1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6524:   PetscCount *perm1prem = PetscSafePointerPlusOffset(perm1, rem);
6525:   PetscCall(PetscMalloc1(nleaves, &Cperm1));
6526:   PetscCall(PetscArraycpy(Cperm1, perm1prem, nleaves));

6528:   /* Support for HYPRE matrices, kind of a hack.
6529:      Swap min column with diagonal so that diagonal values will go first */
6530:   PetscBool hypre;
6531:   PetscCall(PetscStrcmp("_internal_COO_mat_for_hypre", ((PetscObject)mat)->name, &hypre));
6532:   if (hypre) {
6533:     PetscInt *minj;
6534:     PetscBT   hasdiag;

6536:     PetscCall(PetscBTCreate(m, &hasdiag));
6537:     PetscCall(PetscMalloc1(m, &minj));
6538:     for (k = 0; k < m; k++) minj[k] = PETSC_INT_MAX;
6539:     for (k = i1start; k < rem; k++) {
6540:       if (j1[k] < cstart || j1[k] >= cend) continue;
6541:       const PetscInt rindex = i1[k] - rstart;
6542:       if ((j1[k] - cstart) == rindex) PetscCall(PetscBTSet(hasdiag, rindex));
6543:       minj[rindex] = PetscMin(minj[rindex], j1[k]);
6544:     }
6545:     for (k = 0; k < n2; k++) {
6546:       if (j2[k] < cstart || j2[k] >= cend) continue;
6547:       const PetscInt rindex = i2[k] - rstart;
6548:       if ((j2[k] - cstart) == rindex) PetscCall(PetscBTSet(hasdiag, rindex));
6549:       minj[rindex] = PetscMin(minj[rindex], j2[k]);
6550:     }
6551:     for (k = i1start; k < rem; k++) {
6552:       const PetscInt rindex = i1[k] - rstart;
6553:       if (j1[k] < cstart || j1[k] >= cend || !PetscBTLookup(hasdiag, rindex)) continue;
6554:       if (j1[k] == minj[rindex]) j1[k] = i1[k] + (cstart - rstart);
6555:       else if ((j1[k] - cstart) == rindex) j1[k] = minj[rindex];
6556:     }
6557:     for (k = 0; k < n2; k++) {
6558:       const PetscInt rindex = i2[k] - rstart;
6559:       if (j2[k] < cstart || j2[k] >= cend || !PetscBTLookup(hasdiag, rindex)) continue;
6560:       if (j2[k] == minj[rindex]) j2[k] = i2[k] + (cstart - rstart);
6561:       else if ((j2[k] - cstart) == rindex) j2[k] = minj[rindex];
6562:     }
6563:     PetscCall(PetscBTDestroy(&hasdiag));
6564:     PetscCall(PetscFree(minj));
6565:   }

6567:   /* Split local COOs and received COOs into diag/offdiag portions */
6568:   PetscCount *rowBegin1, *rowMid1, *rowEnd1;
6569:   PetscCount *Ajmap1, *Aperm1, *Bjmap1, *Bperm1;
6570:   PetscCount  Annz1, Bnnz1, Atot1, Btot1;
6571:   PetscCount *rowBegin2, *rowMid2, *rowEnd2;
6572:   PetscCount *Ajmap2, *Aperm2, *Bjmap2, *Bperm2;
6573:   PetscCount  Annz2, Bnnz2, Atot2, Btot2;

6575:   PetscCall(PetscCalloc3(m, &rowBegin1, m, &rowMid1, m, &rowEnd1));
6576:   PetscCall(PetscCalloc3(m, &rowBegin2, m, &rowMid2, m, &rowEnd2));
6577:   PetscCall(MatSplitEntries_Internal(mat, rem, i1, j1, perm1, rowBegin1, rowMid1, rowEnd1, &Atot1, &Aperm1, &Annz1, &Ajmap1, &Btot1, &Bperm1, &Bnnz1, &Bjmap1));
6578:   PetscCall(MatSplitEntries_Internal(mat, n2, i2, j2, perm2, rowBegin2, rowMid2, rowEnd2, &Atot2, &Aperm2, &Annz2, &Ajmap2, &Btot2, &Bperm2, &Bnnz2, &Bjmap2));

6580:   /* Merge local COOs with received COOs: diag with diag, offdiag with offdiag */
6581:   PetscInt *Ai, *Bi;
6582:   PetscInt *Aj, *Bj;

6584:   PetscCall(PetscMalloc1(m + 1, &Ai));
6585:   PetscCall(PetscMalloc1(m + 1, &Bi));
6586:   PetscCall(PetscMalloc1(Annz1 + Annz2, &Aj)); /* Since local and remote entries might have dups, we might allocate excess memory */
6587:   PetscCall(PetscMalloc1(Bnnz1 + Bnnz2, &Bj));

6589:   PetscCount *Aimap1, *Bimap1, *Aimap2, *Bimap2;
6590:   PetscCall(PetscMalloc1(Annz1, &Aimap1));
6591:   PetscCall(PetscMalloc1(Bnnz1, &Bimap1));
6592:   PetscCall(PetscMalloc1(Annz2, &Aimap2));
6593:   PetscCall(PetscMalloc1(Bnnz2, &Bimap2));

6595:   PetscCall(MatMergeEntries_Internal(mat, j1, j2, rowBegin1, rowMid1, rowBegin2, rowMid2, Ajmap1, Ajmap2, Aimap1, Aimap2, Ai, Aj));
6596:   PetscCall(MatMergeEntries_Internal(mat, j1, j2, rowMid1, rowEnd1, rowMid2, rowEnd2, Bjmap1, Bjmap2, Bimap1, Bimap2, Bi, Bj));

6598:   /* Expand Ajmap1/Bjmap1 to make them based off nonzeros in A/B, since we     */
6599:   /* expect nonzeros in A/B most likely have local contributing entries        */
6600:   PetscInt    Annz = Ai[m];
6601:   PetscInt    Bnnz = Bi[m];
6602:   PetscCount *Ajmap1_new, *Bjmap1_new;

6604:   PetscCall(PetscMalloc1(Annz + 1, &Ajmap1_new));
6605:   PetscCall(PetscMalloc1(Bnnz + 1, &Bjmap1_new));

6607:   PetscCall(ExpandJmap_Internal(Annz1, Annz, Aimap1, Ajmap1, Ajmap1_new));
6608:   PetscCall(ExpandJmap_Internal(Bnnz1, Bnnz, Bimap1, Bjmap1, Bjmap1_new));

6610:   PetscCall(PetscFree(Aimap1));
6611:   PetscCall(PetscFree(Ajmap1));
6612:   PetscCall(PetscFree(Bimap1));
6613:   PetscCall(PetscFree(Bjmap1));
6614:   PetscCall(PetscFree3(rowBegin1, rowMid1, rowEnd1));
6615:   PetscCall(PetscFree3(rowBegin2, rowMid2, rowEnd2));
6616:   PetscCall(PetscFree(perm1));
6617:   PetscCall(PetscFree3(i2, j2, perm2));

6619:   Ajmap1 = Ajmap1_new;
6620:   Bjmap1 = Bjmap1_new;

6622:   /* Reallocate Aj, Bj once we know actual numbers of unique nonzeros in A and B */
6623:   if (Annz < Annz1 + Annz2) {
6624:     PetscInt *Aj_new;
6625:     PetscCall(PetscMalloc1(Annz, &Aj_new));
6626:     PetscCall(PetscArraycpy(Aj_new, Aj, Annz));
6627:     PetscCall(PetscFree(Aj));
6628:     Aj = Aj_new;
6629:   }

6631:   if (Bnnz < Bnnz1 + Bnnz2) {
6632:     PetscInt *Bj_new;
6633:     PetscCall(PetscMalloc1(Bnnz, &Bj_new));
6634:     PetscCall(PetscArraycpy(Bj_new, Bj, Bnnz));
6635:     PetscCall(PetscFree(Bj));
6636:     Bj = Bj_new;
6637:   }

6639:   /* Create new submatrices for on-process and off-process coupling                  */
6640:   PetscScalar     *Aa, *Ba;
6641:   MatType          rtype;
6642:   Mat_SeqAIJ      *a, *b;
6643:   PetscObjectState state;
6644:   PetscCall(PetscCalloc1(Annz, &Aa)); /* Zero matrix on device */
6645:   PetscCall(PetscCalloc1(Bnnz, &Ba));
6646:   /* make Aj[] local, i.e, based off the start column of the diagonal portion */
6647:   if (cstart) {
6648:     for (k = 0; k < Annz; k++) Aj[k] -= cstart;
6649:   }

6651:   PetscCall(MatGetRootType_Private(mat, &rtype));

6653:   MatSeqXAIJGetOptions_Private(mpiaij->A);
6654:   PetscCall(MatDestroy(&mpiaij->A));
6655:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, n, Ai, Aj, Aa, &mpiaij->A));
6656:   PetscCall(MatSetBlockSizesFromMats(mpiaij->A, mat, mat));
6657:   MatSeqXAIJRestoreOptions_Private(mpiaij->A);

6659:   MatSeqXAIJGetOptions_Private(mpiaij->B);
6660:   PetscCall(MatDestroy(&mpiaij->B));
6661:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, mat->cmap->N, Bi, Bj, Ba, &mpiaij->B));
6662:   PetscCall(MatSetBlockSizesFromMats(mpiaij->B, mat, mat));
6663:   MatSeqXAIJRestoreOptions_Private(mpiaij->B);

6665:   PetscCall(MatSetUpMultiply_MPIAIJ(mat));
6666:   mat->was_assembled = PETSC_TRUE; // was_assembled in effect means the Mvctx is built; doing so avoids redundant MatSetUpMultiply_MPIAIJ
6667:   state              = mpiaij->A->nonzerostate + mpiaij->B->nonzerostate;
6668:   PetscCallMPI(MPIU_Allreduce(&state, &mat->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)mat)));

6670:   a          = (Mat_SeqAIJ *)mpiaij->A->data;
6671:   b          = (Mat_SeqAIJ *)mpiaij->B->data;
6672:   a->free_a  = PETSC_TRUE;
6673:   a->free_ij = PETSC_TRUE;
6674:   b->free_a  = PETSC_TRUE;
6675:   b->free_ij = PETSC_TRUE;
6676:   a->maxnz   = a->nz;
6677:   b->maxnz   = b->nz;

6679:   /* conversion must happen AFTER multiply setup */
6680:   PetscCall(MatConvert(mpiaij->A, rtype, MAT_INPLACE_MATRIX, &mpiaij->A));
6681:   PetscCall(MatConvert(mpiaij->B, rtype, MAT_INPLACE_MATRIX, &mpiaij->B));
6682:   PetscCall(VecDestroy(&mpiaij->lvec));
6683:   PetscCall(MatCreateVecs(mpiaij->B, &mpiaij->lvec, NULL));

6685:   // Put the COO struct in a container and then attach that to the matrix
6686:   PetscCall(PetscMalloc1(1, &coo));
6687:   coo->n       = coo_n;
6688:   coo->sf      = sf2;
6689:   coo->sendlen = nleaves;
6690:   coo->recvlen = nroots;
6691:   coo->Annz    = Annz;
6692:   coo->Bnnz    = Bnnz;
6693:   coo->Annz2   = Annz2;
6694:   coo->Bnnz2   = Bnnz2;
6695:   coo->Atot1   = Atot1;
6696:   coo->Atot2   = Atot2;
6697:   coo->Btot1   = Btot1;
6698:   coo->Btot2   = Btot2;
6699:   coo->Ajmap1  = Ajmap1;
6700:   coo->Aperm1  = Aperm1;
6701:   coo->Bjmap1  = Bjmap1;
6702:   coo->Bperm1  = Bperm1;
6703:   coo->Aimap2  = Aimap2;
6704:   coo->Ajmap2  = Ajmap2;
6705:   coo->Aperm2  = Aperm2;
6706:   coo->Bimap2  = Bimap2;
6707:   coo->Bjmap2  = Bjmap2;
6708:   coo->Bperm2  = Bperm2;
6709:   coo->Cperm1  = Cperm1;
6710:   // Allocate in preallocation. If not used, it has zero cost on host
6711:   PetscCall(PetscMalloc2(coo->sendlen, &coo->sendbuf, coo->recvlen, &coo->recvbuf));
6712:   PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &container));
6713:   PetscCall(PetscContainerSetPointer(container, coo));
6714:   PetscCall(PetscContainerSetCtxDestroy(container, MatCOOStructDestroy_MPIAIJ));
6715:   PetscCall(PetscObjectCompose((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject)container));
6716:   PetscCall(PetscContainerDestroy(&container));
6717:   PetscFunctionReturn(PETSC_SUCCESS);
6718: }

6720: static PetscErrorCode MatSetValuesCOO_MPIAIJ(Mat mat, const PetscScalar v[], InsertMode imode)
6721: {
6722:   Mat_MPIAIJ          *mpiaij = (Mat_MPIAIJ *)mat->data;
6723:   Mat                  A = mpiaij->A, B = mpiaij->B;
6724:   PetscScalar         *Aa, *Ba;
6725:   PetscScalar         *sendbuf, *recvbuf;
6726:   const PetscCount    *Ajmap1, *Ajmap2, *Aimap2;
6727:   const PetscCount    *Bjmap1, *Bjmap2, *Bimap2;
6728:   const PetscCount    *Aperm1, *Aperm2, *Bperm1, *Bperm2;
6729:   const PetscCount    *Cperm1;
6730:   PetscContainer       container;
6731:   MatCOOStruct_MPIAIJ *coo;

6733:   PetscFunctionBegin;
6734:   PetscCall(PetscObjectQuery((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject *)&container));
6735:   PetscCheck(container, PetscObjectComm((PetscObject)mat), PETSC_ERR_PLIB, "Not found MatCOOStruct on this matrix");
6736:   PetscCall(PetscContainerGetPointer(container, (void **)&coo));
6737:   sendbuf = coo->sendbuf;
6738:   recvbuf = coo->recvbuf;
6739:   Ajmap1  = coo->Ajmap1;
6740:   Ajmap2  = coo->Ajmap2;
6741:   Aimap2  = coo->Aimap2;
6742:   Bjmap1  = coo->Bjmap1;
6743:   Bjmap2  = coo->Bjmap2;
6744:   Bimap2  = coo->Bimap2;
6745:   Aperm1  = coo->Aperm1;
6746:   Aperm2  = coo->Aperm2;
6747:   Bperm1  = coo->Bperm1;
6748:   Bperm2  = coo->Bperm2;
6749:   Cperm1  = coo->Cperm1;

6751:   PetscCall(MatSeqAIJGetArray(A, &Aa)); /* Might read and write matrix values */
6752:   PetscCall(MatSeqAIJGetArray(B, &Ba));

6754:   /* Pack entries to be sent to remote */
6755:   for (PetscCount i = 0; i < coo->sendlen; i++) sendbuf[i] = v[Cperm1[i]];

6757:   /* Send remote entries to their owner and overlap the communication with local computation */
6758:   PetscCall(PetscSFReduceWithMemTypeBegin(coo->sf, MPIU_SCALAR, PETSC_MEMTYPE_HOST, sendbuf, PETSC_MEMTYPE_HOST, recvbuf, MPI_REPLACE));
6759:   /* Add local entries to A and B */
6760:   for (PetscCount i = 0; i < coo->Annz; i++) { /* All nonzeros in A are either zero'ed or added with a value (i.e., initialized) */
6761:     PetscScalar sum = 0.0;                     /* Do partial summation first to improve numerical stability */
6762:     for (PetscCount k = Ajmap1[i]; k < Ajmap1[i + 1]; k++) sum += v[Aperm1[k]];
6763:     Aa[i] = (imode == INSERT_VALUES ? 0.0 : Aa[i]) + sum;
6764:   }
6765:   for (PetscCount i = 0; i < coo->Bnnz; i++) {
6766:     PetscScalar sum = 0.0;
6767:     for (PetscCount k = Bjmap1[i]; k < Bjmap1[i + 1]; k++) sum += v[Bperm1[k]];
6768:     Ba[i] = (imode == INSERT_VALUES ? 0.0 : Ba[i]) + sum;
6769:   }
6770:   PetscCall(PetscSFReduceEnd(coo->sf, MPIU_SCALAR, sendbuf, recvbuf, MPI_REPLACE));

6772:   /* Add received remote entries to A and B */
6773:   for (PetscCount i = 0; i < coo->Annz2; i++) {
6774:     for (PetscCount k = Ajmap2[i]; k < Ajmap2[i + 1]; k++) Aa[Aimap2[i]] += recvbuf[Aperm2[k]];
6775:   }
6776:   for (PetscCount i = 0; i < coo->Bnnz2; i++) {
6777:     for (PetscCount k = Bjmap2[i]; k < Bjmap2[i + 1]; k++) Ba[Bimap2[i]] += recvbuf[Bperm2[k]];
6778:   }
6779:   PetscCall(MatSeqAIJRestoreArray(A, &Aa));
6780:   PetscCall(MatSeqAIJRestoreArray(B, &Ba));
6781:   PetscFunctionReturn(PETSC_SUCCESS);
6782: }

6784: /*MC
6785:    MATMPIAIJ - MATMPIAIJ = "mpiaij" - A matrix type to be used for parallel sparse matrices.

6787:    Options Database Keys:
6788: . -mat_type mpiaij - sets the matrix type to `MATMPIAIJ` during a call to `MatSetFromOptions()`

6790:    Level: beginner

6792:    Notes:
6793:    `MatSetValues()` may be called for this matrix type with a `NULL` argument for the numerical values,
6794:     in this case the values associated with the rows and columns one passes in are set to zero
6795:     in the matrix

6797:     `MatSetOptions`(,`MAT_STRUCTURE_ONLY`,`PETSC_TRUE`) may be called for this matrix type. In this no
6798:     space is allocated for the nonzero entries and any entries passed with `MatSetValues()` are ignored

6800: .seealso: [](ch_matrices), `Mat`, `MATSEQAIJ`, `MATAIJ`, `MatCreateAIJ()`
6801: M*/
6802: PETSC_EXTERN PetscErrorCode MatCreate_MPIAIJ(Mat B)
6803: {
6804:   Mat_MPIAIJ *b;
6805:   PetscMPIInt size;

6807:   PetscFunctionBegin;
6808:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)B), &size));

6810:   PetscCall(PetscNew(&b));
6811:   B->data       = (void *)b;
6812:   B->ops[0]     = MatOps_Values;
6813:   B->assembled  = PETSC_FALSE;
6814:   B->insertmode = NOT_SET_VALUES;
6815:   b->size       = size;

6817:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)B), &b->rank));

6819:   /* build cache for off array entries formed */
6820:   PetscCall(MatStashCreate_Private(PetscObjectComm((PetscObject)B), 1, &B->stash));

6822:   b->donotstash  = PETSC_FALSE;
6823:   b->colmap      = NULL;
6824:   b->garray      = NULL;
6825:   b->roworiented = PETSC_TRUE;

6827:   /* stuff used for matrix vector multiply */
6828:   b->lvec  = NULL;
6829:   b->Mvctx = NULL;

6831:   /* stuff for MatGetRow() */
6832:   b->rowindices   = NULL;
6833:   b->rowvalues    = NULL;
6834:   b->getrowactive = PETSC_FALSE;

6836:   /* flexible pointer used in CUSPARSE classes */
6837:   b->spptr = NULL;

6839:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetUseScalableIncreaseOverlap_C", MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ));
6840:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatStoreValues_C", MatStoreValues_MPIAIJ));
6841:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatRetrieveValues_C", MatRetrieveValues_MPIAIJ));
6842:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatIsTranspose_C", MatIsTranspose_MPIAIJ));
6843:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetPreallocation_C", MatMPIAIJSetPreallocation_MPIAIJ));
6844:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatResetPreallocation_C", MatResetPreallocation_MPIAIJ));
6845:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatResetHash_C", MatResetHash_MPIAIJ));
6846:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetPreallocationCSR_C", MatMPIAIJSetPreallocationCSR_MPIAIJ));
6847:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatDiagonalScaleLocal_C", MatDiagonalScaleLocal_MPIAIJ));
6848:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijperm_C", MatConvert_MPIAIJ_MPIAIJPERM));
6849:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijsell_C", MatConvert_MPIAIJ_MPIAIJSELL));
6850: #if defined(PETSC_HAVE_CUDA)
6851:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijcusparse_C", MatConvert_MPIAIJ_MPIAIJCUSPARSE));
6852: #endif
6853: #if defined(PETSC_HAVE_HIP)
6854:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijhipsparse_C", MatConvert_MPIAIJ_MPIAIJHIPSPARSE));
6855: #endif
6856: #if defined(PETSC_HAVE_KOKKOS_KERNELS)
6857:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijkokkos_C", MatConvert_MPIAIJ_MPIAIJKokkos));
6858: #endif
6859: #if defined(PETSC_HAVE_MKL_SPARSE)
6860:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijmkl_C", MatConvert_MPIAIJ_MPIAIJMKL));
6861: #endif
6862:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijcrl_C", MatConvert_MPIAIJ_MPIAIJCRL));
6863:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpibaij_C", MatConvert_MPIAIJ_MPIBAIJ));
6864:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpisbaij_C", MatConvert_MPIAIJ_MPISBAIJ));
6865:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpidense_C", MatConvert_MPIAIJ_MPIDense));
6866: #if defined(PETSC_HAVE_ELEMENTAL)
6867:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_elemental_C", MatConvert_MPIAIJ_Elemental));
6868: #endif
6869: #if defined(PETSC_HAVE_SCALAPACK)
6870:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_scalapack_C", MatConvert_AIJ_ScaLAPACK));
6871: #endif
6872:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_is_C", MatConvert_XAIJ_IS));
6873:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpisell_C", MatConvert_MPIAIJ_MPISELL));
6874: #if defined(PETSC_HAVE_HYPRE)
6875:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_hypre_C", MatConvert_AIJ_HYPRE));
6876:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_transpose_mpiaij_mpiaij_C", MatProductSetFromOptions_Transpose_AIJ_AIJ));
6877: #endif
6878:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_is_mpiaij_C", MatProductSetFromOptions_IS_XAIJ));
6879:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_mpiaij_mpiaij_C", MatProductSetFromOptions_MPIAIJ));
6880:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatSetPreallocationCOO_C", MatSetPreallocationCOO_MPIAIJ));
6881:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatSetValuesCOO_C", MatSetValuesCOO_MPIAIJ));
6882:   PetscCall(PetscObjectChangeTypeName((PetscObject)B, MATMPIAIJ));
6883:   PetscFunctionReturn(PETSC_SUCCESS);
6884: }

6886: /*@
6887:   MatCreateMPIAIJWithSplitArrays - creates a `MATMPIAIJ` matrix using arrays that contain the "diagonal"
6888:   and "off-diagonal" part of the matrix in CSR format.

6890:   Collective

6892:   Input Parameters:
6893: + comm - MPI communicator
6894: . m    - number of local rows (Cannot be `PETSC_DECIDE`)
6895: . n    - This value should be the same as the local size used in creating the
6896:          x vector for the matrix-vector product $y = Ax$. (or `PETSC_DECIDE` to have
6897:          calculated if `N` is given) For square matrices `n` is almost always `m`.
6898: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if `m` is given)
6899: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if `n` is given)
6900: . 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
6901: . j    - column indices, which must be local, i.e., based off the start column of the diagonal portion
6902: . a    - matrix values
6903: . 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
6904: . oj   - column indices, which must be global, representing global columns in the `MATMPIAIJ` matrix
6905: - oa   - matrix values

6907:   Output Parameter:
6908: . mat - the matrix

6910:   Level: advanced

6912:   Notes:
6913:   The `i`, `j`, and `a` arrays ARE NOT copied by this routine into the internal format used by PETSc (even in Fortran). The user
6914:   must free the arrays once the matrix has been destroyed and not before.

6916:   The `i` and `j` indices are 0 based

6918:   See `MatCreateAIJ()` for the definition of "diagonal" and "off-diagonal" portion of the matrix

6920:   This sets local rows and cannot be used to set off-processor values.

6922:   Use of this routine is discouraged because it is inflexible and cumbersome to use. It is extremely rare that a
6923:   legacy application natively assembles into exactly this split format. The code to do so is nontrivial and does
6924:   not easily support in-place reassembly. It is recommended to use MatSetValues() (or a variant thereof) because
6925:   the resulting assembly is easier to implement, will work with any matrix format, and the user does not have to
6926:   keep track of the underlying array. Use `MatSetOption`(A,`MAT_NO_OFF_PROC_ENTRIES`,`PETSC_TRUE`) to disable all
6927:   communication if it is known that only local entries will be set.

6929: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
6930:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithArrays()`
6931: @*/
6932: 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)
6933: {
6934:   Mat_MPIAIJ *maij;

6936:   PetscFunctionBegin;
6937:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
6938:   PetscCheck(i[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
6939:   PetscCheck(oi[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "oi (row indices) must start with 0");
6940:   PetscCall(MatCreate(comm, mat));
6941:   PetscCall(MatSetSizes(*mat, m, n, M, N));
6942:   PetscCall(MatSetType(*mat, MATMPIAIJ));
6943:   maij = (Mat_MPIAIJ *)(*mat)->data;

6945:   (*mat)->preallocated = PETSC_TRUE;

6947:   PetscCall(PetscLayoutSetUp((*mat)->rmap));
6948:   PetscCall(PetscLayoutSetUp((*mat)->cmap));

6950:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, n, i, j, a, &maij->A));
6951:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, (*mat)->cmap->N, oi, oj, oa, &maij->B));

6953:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
6954:   PetscCall(MatAssemblyBegin(*mat, MAT_FINAL_ASSEMBLY));
6955:   PetscCall(MatAssemblyEnd(*mat, MAT_FINAL_ASSEMBLY));
6956:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_FALSE));
6957:   PetscCall(MatSetOption(*mat, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
6958:   PetscFunctionReturn(PETSC_SUCCESS);
6959: }

6961: typedef struct {
6962:   Mat       *mp;    /* intermediate products */
6963:   PetscBool *mptmp; /* is the intermediate product temporary ? */
6964:   PetscInt   cp;    /* number of intermediate products */

6966:   /* support for MatGetBrowsOfAoCols_MPIAIJ for P_oth */
6967:   PetscInt    *startsj_s, *startsj_r;
6968:   PetscScalar *bufa;
6969:   Mat          P_oth;

6971:   /* may take advantage of merging product->B */
6972:   Mat Bloc; /* B-local by merging diag and off-diag */

6974:   /* cusparse does not have support to split between symbolic and numeric phases.
6975:      When api_user is true, we don't need to update the numerical values
6976:      of the temporary storage */
6977:   PetscBool reusesym;

6979:   /* support for COO values insertion */
6980:   PetscScalar *coo_v, *coo_w; /* store on-process and off-process COO scalars, and used as MPI recv/send buffers respectively */
6981:   PetscInt   **own;           /* own[i] points to address of on-process COO indices for Mat mp[i] */
6982:   PetscInt   **off;           /* off[i] points to address of off-process COO indices for Mat mp[i] */
6983:   PetscBool    hasoffproc;    /* if true, have off-process values insertion (i.e. AtB or PtAP) */
6984:   PetscSF      sf;            /* used for non-local values insertion and memory malloc */
6985:   PetscMemType mtype;

6987:   /* customization */
6988:   PetscBool abmerge;
6989:   PetscBool P_oth_bind;
6990: } MatMatMPIAIJBACKEND;

6992: static PetscErrorCode MatDestroy_MatMatMPIAIJBACKEND(void *data)
6993: {
6994:   MatMatMPIAIJBACKEND *mmdata = (MatMatMPIAIJBACKEND *)data;
6995:   PetscInt             i;

6997:   PetscFunctionBegin;
6998:   PetscCall(PetscFree2(mmdata->startsj_s, mmdata->startsj_r));
6999:   PetscCall(PetscFree(mmdata->bufa));
7000:   PetscCall(PetscSFFree(mmdata->sf, mmdata->mtype, mmdata->coo_v));
7001:   PetscCall(PetscSFFree(mmdata->sf, mmdata->mtype, mmdata->coo_w));
7002:   PetscCall(MatDestroy(&mmdata->P_oth));
7003:   PetscCall(MatDestroy(&mmdata->Bloc));
7004:   PetscCall(PetscSFDestroy(&mmdata->sf));
7005:   for (i = 0; i < mmdata->cp; i++) PetscCall(MatDestroy(&mmdata->mp[i]));
7006:   PetscCall(PetscFree2(mmdata->mp, mmdata->mptmp));
7007:   PetscCall(PetscFree(mmdata->own[0]));
7008:   PetscCall(PetscFree(mmdata->own));
7009:   PetscCall(PetscFree(mmdata->off[0]));
7010:   PetscCall(PetscFree(mmdata->off));
7011:   PetscCall(PetscFree(mmdata));
7012:   PetscFunctionReturn(PETSC_SUCCESS);
7013: }

7015: /* Copy selected n entries with indices in idx[] of A to v[].
7016:    If idx is NULL, copy the whole data array of A to v[]
7017:  */
7018: static PetscErrorCode MatSeqAIJCopySubArray(Mat A, PetscInt n, const PetscInt idx[], PetscScalar v[])
7019: {
7020:   PetscErrorCode (*f)(Mat, PetscInt, const PetscInt[], PetscScalar[]);

7022:   PetscFunctionBegin;
7023:   PetscCall(PetscObjectQueryFunction((PetscObject)A, "MatSeqAIJCopySubArray_C", &f));
7024:   if (f) {
7025:     PetscCall((*f)(A, n, idx, v));
7026:   } else {
7027:     const PetscScalar *vv;

7029:     PetscCall(MatSeqAIJGetArrayRead(A, &vv));
7030:     if (n && idx) {
7031:       PetscScalar    *w  = v;
7032:       const PetscInt *oi = idx;
7033:       PetscInt        j;

7035:       for (j = 0; j < n; j++) *w++ = vv[*oi++];
7036:     } else {
7037:       PetscCall(PetscArraycpy(v, vv, n));
7038:     }
7039:     PetscCall(MatSeqAIJRestoreArrayRead(A, &vv));
7040:   }
7041:   PetscFunctionReturn(PETSC_SUCCESS);
7042: }

7044: static PetscErrorCode MatProductNumeric_MPIAIJBACKEND(Mat C)
7045: {
7046:   MatMatMPIAIJBACKEND *mmdata;
7047:   PetscInt             i, n_d, n_o;

7049:   PetscFunctionBegin;
7050:   MatCheckProduct(C, 1);
7051:   PetscCheck(C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data empty");
7052:   mmdata = (MatMatMPIAIJBACKEND *)C->product->data;
7053:   if (!mmdata->reusesym) { /* update temporary matrices */
7054:     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));
7055:     if (mmdata->Bloc) PetscCall(MatMPIAIJGetLocalMatMerge(C->product->B, MAT_REUSE_MATRIX, NULL, &mmdata->Bloc));
7056:   }
7057:   mmdata->reusesym = PETSC_FALSE;

7059:   for (i = 0; i < mmdata->cp; i++) {
7060:     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]);
7061:     PetscCall((*mmdata->mp[i]->ops->productnumeric)(mmdata->mp[i]));
7062:   }
7063:   for (i = 0, n_d = 0, n_o = 0; i < mmdata->cp; i++) {
7064:     PetscInt noff;

7066:     PetscCall(PetscIntCast(mmdata->off[i + 1] - mmdata->off[i], &noff));
7067:     if (mmdata->mptmp[i]) continue;
7068:     if (noff) {
7069:       PetscInt nown;

7071:       PetscCall(PetscIntCast(mmdata->own[i + 1] - mmdata->own[i], &nown));
7072:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], noff, mmdata->off[i], mmdata->coo_w + n_o));
7073:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], nown, mmdata->own[i], mmdata->coo_v + n_d));
7074:       n_o += noff;
7075:       n_d += nown;
7076:     } else {
7077:       Mat_SeqAIJ *mm = (Mat_SeqAIJ *)mmdata->mp[i]->data;

7079:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], mm->nz, NULL, mmdata->coo_v + n_d));
7080:       n_d += mm->nz;
7081:     }
7082:   }
7083:   if (mmdata->hasoffproc) { /* offprocess insertion */
7084:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_SCALAR, mmdata->coo_w, mmdata->coo_v + n_d));
7085:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_SCALAR, mmdata->coo_w, mmdata->coo_v + n_d));
7086:   }
7087:   PetscCall(MatSetValuesCOO(C, mmdata->coo_v, INSERT_VALUES));
7088:   PetscFunctionReturn(PETSC_SUCCESS);
7089: }

7091: /* Support for Pt * A, A * P, or Pt * A * P */
7092: #define MAX_NUMBER_INTERMEDIATE 4
7093: PetscErrorCode MatProductSymbolic_MPIAIJBACKEND(Mat C)
7094: {
7095:   Mat_Product           *product = C->product;
7096:   Mat                    A, P, mp[MAX_NUMBER_INTERMEDIATE]; /* A, P and a series of intermediate matrices */
7097:   Mat_MPIAIJ            *a, *p;
7098:   MatMatMPIAIJBACKEND   *mmdata;
7099:   ISLocalToGlobalMapping P_oth_l2g = NULL;
7100:   IS                     glob      = NULL;
7101:   const char            *prefix;
7102:   char                   pprefix[256];
7103:   const PetscInt        *globidx, *P_oth_idx;
7104:   PetscInt               i, j, cp, m, n, M, N, *coo_i, *coo_j;
7105:   PetscCount             ncoo, ncoo_d, ncoo_o, ncoo_oown;
7106:   PetscInt               cmapt[MAX_NUMBER_INTERMEDIATE], rmapt[MAX_NUMBER_INTERMEDIATE]; /* col/row map type for each Mat in mp[]. */
7107:                                                                                          /* type-0: consecutive, start from 0; type-1: consecutive with */
7108:                                                                                          /* a base offset; type-2: sparse with a local to global map table */
7109:   const PetscInt *cmapa[MAX_NUMBER_INTERMEDIATE], *rmapa[MAX_NUMBER_INTERMEDIATE];       /* col/row local to global map array (table) for type-2 map type */

7111:   MatProductType ptype;
7112:   PetscBool      mptmp[MAX_NUMBER_INTERMEDIATE], hasoffproc = PETSC_FALSE, iscuda, iship, iskokk;
7113:   PetscMPIInt    size;

7115:   PetscFunctionBegin;
7116:   MatCheckProduct(C, 1);
7117:   PetscCheck(!product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data not empty");
7118:   ptype = product->type;
7119:   if (product->A->symmetric == PETSC_BOOL3_TRUE && ptype == MATPRODUCT_AtB) {
7120:     ptype                                          = MATPRODUCT_AB;
7121:     product->symbolic_used_the_fact_A_is_symmetric = PETSC_TRUE;
7122:   }
7123:   switch (ptype) {
7124:   case MATPRODUCT_AB:
7125:     A          = product->A;
7126:     P          = product->B;
7127:     m          = A->rmap->n;
7128:     n          = P->cmap->n;
7129:     M          = A->rmap->N;
7130:     N          = P->cmap->N;
7131:     hasoffproc = PETSC_FALSE; /* will not scatter mat product values to other processes */
7132:     break;
7133:   case MATPRODUCT_AtB:
7134:     P          = product->A;
7135:     A          = product->B;
7136:     m          = P->cmap->n;
7137:     n          = A->cmap->n;
7138:     M          = P->cmap->N;
7139:     N          = A->cmap->N;
7140:     hasoffproc = PETSC_TRUE;
7141:     break;
7142:   case MATPRODUCT_PtAP:
7143:     A          = product->A;
7144:     P          = product->B;
7145:     m          = P->cmap->n;
7146:     n          = P->cmap->n;
7147:     M          = P->cmap->N;
7148:     N          = P->cmap->N;
7149:     hasoffproc = PETSC_TRUE;
7150:     break;
7151:   default:
7152:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[ptype]);
7153:   }
7154:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)C), &size));
7155:   if (size == 1) hasoffproc = PETSC_FALSE;

7157:   /* defaults */
7158:   for (i = 0; i < MAX_NUMBER_INTERMEDIATE; i++) {
7159:     mp[i]    = NULL;
7160:     mptmp[i] = PETSC_FALSE;
7161:     rmapt[i] = -1;
7162:     cmapt[i] = -1;
7163:     rmapa[i] = NULL;
7164:     cmapa[i] = NULL;
7165:   }

7167:   /* customization */
7168:   PetscCall(PetscNew(&mmdata));
7169:   mmdata->reusesym = product->api_user;
7170:   if (ptype == MATPRODUCT_AB) {
7171:     if (product->api_user) {
7172:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatMatMult", "Mat");
7173:       PetscCall(PetscOptionsBool("-matmatmult_backend_mergeB", "Merge product->B local matrices", "MatMatMult", mmdata->abmerge, &mmdata->abmerge, NULL));
7174:       PetscCall(PetscOptionsBool("-matmatmult_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7175:       PetscOptionsEnd();
7176:     } else {
7177:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_AB", "Mat");
7178:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_mergeB", "Merge product->B local matrices", "MatMatMult", mmdata->abmerge, &mmdata->abmerge, NULL));
7179:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7180:       PetscOptionsEnd();
7181:     }
7182:   } else if (ptype == MATPRODUCT_PtAP) {
7183:     if (product->api_user) {
7184:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatPtAP", "Mat");
7185:       PetscCall(PetscOptionsBool("-matptap_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7186:       PetscOptionsEnd();
7187:     } else {
7188:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_PtAP", "Mat");
7189:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7190:       PetscOptionsEnd();
7191:     }
7192:   }
7193:   a = (Mat_MPIAIJ *)A->data;
7194:   p = (Mat_MPIAIJ *)P->data;
7195:   PetscCall(MatSetSizes(C, m, n, M, N));
7196:   PetscCall(PetscLayoutSetUp(C->rmap));
7197:   PetscCall(PetscLayoutSetUp(C->cmap));
7198:   PetscCall(MatSetType(C, ((PetscObject)A)->type_name));
7199:   PetscCall(MatGetOptionsPrefix(C, &prefix));

7201:   cp = 0;
7202:   switch (ptype) {
7203:   case MATPRODUCT_AB: /* A * P */
7204:     PetscCall(MatGetBrowsOfAoCols_MPIAIJ(A, P, MAT_INITIAL_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));

7206:     /* A_diag * P_local (merged or not) */
7207:     if (mmdata->abmerge) { /* P's diagonal and off-diag blocks are merged to one matrix, then multiplied by A_diag */
7208:       /* P is product->B */
7209:       PetscCall(MatMPIAIJGetLocalMatMerge(P, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7210:       PetscCall(MatProductCreate(a->A, mmdata->Bloc, NULL, &mp[cp]));
7211:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7212:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7213:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7214:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7215:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7216:       mp[cp]->product->api_user = product->api_user;
7217:       PetscCall(MatProductSetFromOptions(mp[cp]));
7218:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7219:       PetscCall(ISGetIndices(glob, &globidx));
7220:       rmapt[cp] = 1;
7221:       cmapt[cp] = 2;
7222:       cmapa[cp] = globidx;
7223:       mptmp[cp] = PETSC_FALSE;
7224:       cp++;
7225:     } else { /* A_diag * P_diag and A_diag * P_off */
7226:       PetscCall(MatProductCreate(a->A, p->A, NULL, &mp[cp]));
7227:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7228:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7229:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7230:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7231:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7232:       mp[cp]->product->api_user = product->api_user;
7233:       PetscCall(MatProductSetFromOptions(mp[cp]));
7234:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7235:       rmapt[cp] = 1;
7236:       cmapt[cp] = 1;
7237:       mptmp[cp] = PETSC_FALSE;
7238:       cp++;
7239:       PetscCall(MatProductCreate(a->A, p->B, NULL, &mp[cp]));
7240:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7241:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7242:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7243:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7244:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7245:       mp[cp]->product->api_user = product->api_user;
7246:       PetscCall(MatProductSetFromOptions(mp[cp]));
7247:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7248:       rmapt[cp] = 1;
7249:       cmapt[cp] = 2;
7250:       cmapa[cp] = p->garray;
7251:       mptmp[cp] = PETSC_FALSE;
7252:       cp++;
7253:     }

7255:     /* A_off * P_other */
7256:     if (mmdata->P_oth) {
7257:       PetscCall(MatSeqAIJCompactOutExtraColumns_SeqAIJ(mmdata->P_oth, &P_oth_l2g)); /* make P_oth use local col ids */
7258:       PetscCall(ISLocalToGlobalMappingGetIndices(P_oth_l2g, &P_oth_idx));
7259:       PetscCall(MatSetType(mmdata->P_oth, ((PetscObject)a->B)->type_name));
7260:       PetscCall(MatBindToCPU(mmdata->P_oth, mmdata->P_oth_bind));
7261:       PetscCall(MatProductCreate(a->B, mmdata->P_oth, NULL, &mp[cp]));
7262:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7263:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7264:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7265:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7266:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7267:       mp[cp]->product->api_user = product->api_user;
7268:       PetscCall(MatProductSetFromOptions(mp[cp]));
7269:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7270:       rmapt[cp] = 1;
7271:       cmapt[cp] = 2;
7272:       cmapa[cp] = P_oth_idx;
7273:       mptmp[cp] = PETSC_FALSE;
7274:       cp++;
7275:     }
7276:     break;

7278:   case MATPRODUCT_AtB: /* (P^t * A): P_diag * A_loc + P_off * A_loc */
7279:     /* A is product->B */
7280:     PetscCall(MatMPIAIJGetLocalMatMerge(A, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7281:     if (A == P) { /* when A==P, we can take advantage of the already merged mmdata->Bloc */
7282:       PetscCall(MatProductCreate(mmdata->Bloc, mmdata->Bloc, NULL, &mp[cp]));
7283:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
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:       PetscCall(ISGetIndices(glob, &globidx));
7292:       rmapt[cp] = 2;
7293:       rmapa[cp] = globidx;
7294:       cmapt[cp] = 2;
7295:       cmapa[cp] = globidx;
7296:       mptmp[cp] = PETSC_FALSE;
7297:       cp++;
7298:     } else {
7299:       PetscCall(MatProductCreate(p->A, mmdata->Bloc, NULL, &mp[cp]));
7300:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7301:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7302:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7303:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7304:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7305:       mp[cp]->product->api_user = product->api_user;
7306:       PetscCall(MatProductSetFromOptions(mp[cp]));
7307:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7308:       PetscCall(ISGetIndices(glob, &globidx));
7309:       rmapt[cp] = 1;
7310:       cmapt[cp] = 2;
7311:       cmapa[cp] = globidx;
7312:       mptmp[cp] = PETSC_FALSE;
7313:       cp++;
7314:       PetscCall(MatProductCreate(p->B, mmdata->Bloc, NULL, &mp[cp]));
7315:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7316:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7317:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7318:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7319:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7320:       mp[cp]->product->api_user = product->api_user;
7321:       PetscCall(MatProductSetFromOptions(mp[cp]));
7322:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7323:       rmapt[cp] = 2;
7324:       rmapa[cp] = p->garray;
7325:       cmapt[cp] = 2;
7326:       cmapa[cp] = globidx;
7327:       mptmp[cp] = PETSC_FALSE;
7328:       cp++;
7329:     }
7330:     break;
7331:   case MATPRODUCT_PtAP:
7332:     PetscCall(MatGetBrowsOfAoCols_MPIAIJ(A, P, MAT_INITIAL_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));
7333:     /* P is product->B */
7334:     PetscCall(MatMPIAIJGetLocalMatMerge(P, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7335:     PetscCall(MatProductCreate(a->A, mmdata->Bloc, NULL, &mp[cp]));
7336:     PetscCall(MatProductSetType(mp[cp], MATPRODUCT_PtAP));
7337:     PetscCall(MatProductSetFill(mp[cp], product->fill));
7338:     PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7339:     PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7340:     PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7341:     mp[cp]->product->api_user = product->api_user;
7342:     PetscCall(MatProductSetFromOptions(mp[cp]));
7343:     PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7344:     PetscCall(ISGetIndices(glob, &globidx));
7345:     rmapt[cp] = 2;
7346:     rmapa[cp] = globidx;
7347:     cmapt[cp] = 2;
7348:     cmapa[cp] = globidx;
7349:     mptmp[cp] = PETSC_FALSE;
7350:     cp++;
7351:     if (mmdata->P_oth) {
7352:       PetscCall(MatSeqAIJCompactOutExtraColumns_SeqAIJ(mmdata->P_oth, &P_oth_l2g));
7353:       PetscCall(ISLocalToGlobalMappingGetIndices(P_oth_l2g, &P_oth_idx));
7354:       PetscCall(MatSetType(mmdata->P_oth, ((PetscObject)a->B)->type_name));
7355:       PetscCall(MatBindToCPU(mmdata->P_oth, mmdata->P_oth_bind));
7356:       PetscCall(MatProductCreate(a->B, mmdata->P_oth, NULL, &mp[cp]));
7357:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7358:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7359:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7360:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7361:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7362:       mp[cp]->product->api_user = product->api_user;
7363:       PetscCall(MatProductSetFromOptions(mp[cp]));
7364:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7365:       mptmp[cp] = PETSC_TRUE;
7366:       cp++;
7367:       PetscCall(MatProductCreate(mmdata->Bloc, mp[1], NULL, &mp[cp]));
7368:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7369:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7370:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7371:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7372:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7373:       mp[cp]->product->api_user = product->api_user;
7374:       PetscCall(MatProductSetFromOptions(mp[cp]));
7375:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7376:       rmapt[cp] = 2;
7377:       rmapa[cp] = globidx;
7378:       cmapt[cp] = 2;
7379:       cmapa[cp] = P_oth_idx;
7380:       mptmp[cp] = PETSC_FALSE;
7381:       cp++;
7382:     }
7383:     break;
7384:   default:
7385:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[ptype]);
7386:   }
7387:   /* sanity check */
7388:   if (size > 1)
7389:     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);

7391:   PetscCall(PetscMalloc2(cp, &mmdata->mp, cp, &mmdata->mptmp));
7392:   for (i = 0; i < cp; i++) {
7393:     mmdata->mp[i]    = mp[i];
7394:     mmdata->mptmp[i] = mptmp[i];
7395:   }
7396:   mmdata->cp             = cp;
7397:   C->product->data       = mmdata;
7398:   C->product->destroy    = MatDestroy_MatMatMPIAIJBACKEND;
7399:   C->ops->productnumeric = MatProductNumeric_MPIAIJBACKEND;

7401:   /* memory type */
7402:   mmdata->mtype = PETSC_MEMTYPE_HOST;
7403:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iscuda, MATSEQAIJCUSPARSE, MATMPIAIJCUSPARSE, ""));
7404:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iship, MATSEQAIJHIPSPARSE, MATMPIAIJHIPSPARSE, ""));
7405:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iskokk, MATSEQAIJKOKKOS, MATMPIAIJKOKKOS, ""));
7406:   if (iscuda) mmdata->mtype = PETSC_MEMTYPE_CUDA;
7407:   else if (iship) mmdata->mtype = PETSC_MEMTYPE_HIP;
7408:   else if (iskokk) mmdata->mtype = PETSC_MEMTYPE_KOKKOS;

7410:   /* prepare coo coordinates for values insertion */

7412:   /* count total nonzeros of those intermediate seqaij Mats
7413:     ncoo_d:    # of nonzeros of matrices that do not have offproc entries
7414:     ncoo_o:    # of nonzeros (of matrices that might have offproc entries) that will be inserted to remote procs
7415:     ncoo_oown: # of nonzeros (of matrices that might have offproc entries) that will be inserted locally
7416:   */
7417:   for (cp = 0, ncoo_d = 0, ncoo_o = 0, ncoo_oown = 0; cp < mmdata->cp; cp++) {
7418:     Mat_SeqAIJ *mm = (Mat_SeqAIJ *)mp[cp]->data;
7419:     if (mptmp[cp]) continue;
7420:     if (rmapt[cp] == 2 && hasoffproc) { /* the rows need to be scatter to all processes (might include self) */
7421:       const PetscInt *rmap = rmapa[cp];
7422:       const PetscInt  mr   = mp[cp]->rmap->n;
7423:       const PetscInt  rs   = C->rmap->rstart;
7424:       const PetscInt  re   = C->rmap->rend;
7425:       const PetscInt *ii   = mm->i;
7426:       for (i = 0; i < mr; i++) {
7427:         const PetscInt gr = rmap[i];
7428:         const PetscInt nz = ii[i + 1] - ii[i];
7429:         if (gr < rs || gr >= re) ncoo_o += nz; /* this row is offproc */
7430:         else ncoo_oown += nz;                  /* this row is local */
7431:       }
7432:     } else ncoo_d += mm->nz;
7433:   }

7435:   /*
7436:     ncoo: total number of nonzeros (including those inserted by remote procs) belonging to this proc

7438:     ncoo = ncoo_d + ncoo_oown + ncoo2, which ncoo2 is number of nonzeros inserted to me by other procs.

7440:     off[0] points to a big index array, which is shared by off[1,2,...]. Similarly, for own[0].

7442:     off[p]: points to the segment for matrix mp[p], storing location of nonzeros that mp[p] will insert to others
7443:     own[p]: points to the segment for matrix mp[p], storing location of nonzeros that mp[p] will insert locally
7444:     so, off[p+1]-off[p] is the number of nonzeros that mp[p] will send to others.

7446:     coo_i/j/v[]: [ncoo] row/col/val of nonzeros belonging to this proc.
7447:     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.
7448:   */
7449:   PetscCall(PetscCalloc1(mmdata->cp + 1, &mmdata->off)); /* +1 to make a csr-like data structure */
7450:   PetscCall(PetscCalloc1(mmdata->cp + 1, &mmdata->own));

7452:   /* gather (i,j) of nonzeros inserted by remote procs */
7453:   if (hasoffproc) {
7454:     PetscSF  msf;
7455:     PetscInt ncoo2, *coo_i2, *coo_j2;

7457:     PetscCall(PetscMalloc1(ncoo_o, &mmdata->off[0]));
7458:     PetscCall(PetscMalloc1(ncoo_oown, &mmdata->own[0]));
7459:     PetscCall(PetscMalloc2(ncoo_o, &coo_i, ncoo_o, &coo_j)); /* to collect (i,j) of entries to be sent to others */

7461:     for (cp = 0, ncoo_o = 0; cp < mmdata->cp; cp++) {
7462:       Mat_SeqAIJ *mm     = (Mat_SeqAIJ *)mp[cp]->data;
7463:       PetscInt   *idxoff = mmdata->off[cp];
7464:       PetscInt   *idxown = mmdata->own[cp];
7465:       if (!mptmp[cp] && rmapt[cp] == 2) { /* row map is sparse */
7466:         const PetscInt *rmap = rmapa[cp];
7467:         const PetscInt *cmap = cmapa[cp];
7468:         const PetscInt *ii   = mm->i;
7469:         PetscInt       *coi  = coo_i + ncoo_o;
7470:         PetscInt       *coj  = coo_j + ncoo_o;
7471:         const PetscInt  mr   = mp[cp]->rmap->n;
7472:         const PetscInt  rs   = C->rmap->rstart;
7473:         const PetscInt  re   = C->rmap->rend;
7474:         const PetscInt  cs   = C->cmap->rstart;
7475:         for (i = 0; i < mr; i++) {
7476:           const PetscInt *jj = mm->j + ii[i];
7477:           const PetscInt  gr = rmap[i];
7478:           const PetscInt  nz = ii[i + 1] - ii[i];
7479:           if (gr < rs || gr >= re) { /* this is an offproc row */
7480:             for (j = ii[i]; j < ii[i + 1]; j++) {
7481:               *coi++    = gr;
7482:               *idxoff++ = j;
7483:             }
7484:             if (!cmapt[cp]) { /* already global */
7485:               for (j = 0; j < nz; j++) *coj++ = jj[j];
7486:             } else if (cmapt[cp] == 1) { /* local to global for owned columns of C */
7487:               for (j = 0; j < nz; j++) *coj++ = jj[j] + cs;
7488:             } else { /* offdiag */
7489:               for (j = 0; j < nz; j++) *coj++ = cmap[jj[j]];
7490:             }
7491:             ncoo_o += nz;
7492:           } else { /* this is a local row */
7493:             for (j = ii[i]; j < ii[i + 1]; j++) *idxown++ = j;
7494:           }
7495:         }
7496:       }
7497:       mmdata->off[cp + 1] = idxoff;
7498:       mmdata->own[cp + 1] = idxown;
7499:     }

7501:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)C), &mmdata->sf));
7502:     PetscInt incoo_o;
7503:     PetscCall(PetscIntCast(ncoo_o, &incoo_o));
7504:     PetscCall(PetscSFSetGraphLayout(mmdata->sf, C->rmap, incoo_o /*nleaves*/, NULL /*ilocal*/, PETSC_OWN_POINTER, coo_i));
7505:     PetscCall(PetscSFGetMultiSF(mmdata->sf, &msf));
7506:     PetscCall(PetscSFGetGraph(msf, &ncoo2 /*nroots*/, NULL, NULL, NULL));
7507:     ncoo = ncoo_d + ncoo_oown + ncoo2;
7508:     PetscCall(PetscMalloc2(ncoo, &coo_i2, ncoo, &coo_j2));
7509:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_INT, coo_i, coo_i2 + ncoo_d + ncoo_oown)); /* put (i,j) of remote nonzeros at back */
7510:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_INT, coo_i, coo_i2 + ncoo_d + ncoo_oown));
7511:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_INT, coo_j, coo_j2 + ncoo_d + ncoo_oown));
7512:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_INT, coo_j, coo_j2 + ncoo_d + ncoo_oown));
7513:     PetscCall(PetscFree2(coo_i, coo_j));
7514:     /* allocate MPI send buffer to collect nonzero values to be sent to remote procs */
7515:     PetscCall(PetscSFMalloc(mmdata->sf, mmdata->mtype, ncoo_o * sizeof(PetscScalar), (void **)&mmdata->coo_w));
7516:     coo_i = coo_i2;
7517:     coo_j = coo_j2;
7518:   } else { /* no offproc values insertion */
7519:     ncoo = ncoo_d;
7520:     PetscCall(PetscMalloc2(ncoo, &coo_i, ncoo, &coo_j));

7522:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)C), &mmdata->sf));
7523:     PetscCall(PetscSFSetGraph(mmdata->sf, 0, 0, NULL, PETSC_OWN_POINTER, NULL, PETSC_OWN_POINTER));
7524:     PetscCall(PetscSFSetUp(mmdata->sf));
7525:   }
7526:   mmdata->hasoffproc = hasoffproc;

7528:   /* gather (i,j) of nonzeros inserted locally */
7529:   for (cp = 0, ncoo_d = 0; cp < mmdata->cp; cp++) {
7530:     Mat_SeqAIJ     *mm   = (Mat_SeqAIJ *)mp[cp]->data;
7531:     PetscInt       *coi  = coo_i + ncoo_d;
7532:     PetscInt       *coj  = coo_j + ncoo_d;
7533:     const PetscInt *jj   = mm->j;
7534:     const PetscInt *ii   = mm->i;
7535:     const PetscInt *cmap = cmapa[cp];
7536:     const PetscInt *rmap = rmapa[cp];
7537:     const PetscInt  mr   = mp[cp]->rmap->n;
7538:     const PetscInt  rs   = C->rmap->rstart;
7539:     const PetscInt  re   = C->rmap->rend;
7540:     const PetscInt  cs   = C->cmap->rstart;

7542:     if (mptmp[cp]) continue;
7543:     if (rmapt[cp] == 1) { /* consecutive rows */
7544:       /* fill coo_i */
7545:       for (i = 0; i < mr; i++) {
7546:         const PetscInt gr = i + rs;
7547:         for (j = ii[i]; j < ii[i + 1]; j++) coi[j] = gr;
7548:       }
7549:       /* fill coo_j */
7550:       if (!cmapt[cp]) { /* type-0, already global */
7551:         PetscCall(PetscArraycpy(coj, jj, mm->nz));
7552:       } else if (cmapt[cp] == 1) {                        /* type-1, local to global for consecutive columns of C */
7553:         for (j = 0; j < mm->nz; j++) coj[j] = jj[j] + cs; /* lid + col start */
7554:       } else {                                            /* type-2, local to global for sparse columns */
7555:         for (j = 0; j < mm->nz; j++) coj[j] = cmap[jj[j]];
7556:       }
7557:       ncoo_d += mm->nz;
7558:     } else if (rmapt[cp] == 2) { /* sparse rows */
7559:       for (i = 0; i < mr; i++) {
7560:         const PetscInt *jj = mm->j + ii[i];
7561:         const PetscInt  gr = rmap[i];
7562:         const PetscInt  nz = ii[i + 1] - ii[i];
7563:         if (gr >= rs && gr < re) { /* local rows */
7564:           for (j = ii[i]; j < ii[i + 1]; j++) *coi++ = gr;
7565:           if (!cmapt[cp]) { /* type-0, already global */
7566:             for (j = 0; j < nz; j++) *coj++ = jj[j];
7567:           } else if (cmapt[cp] == 1) { /* local to global for owned columns of C */
7568:             for (j = 0; j < nz; j++) *coj++ = jj[j] + cs;
7569:           } else { /* type-2, local to global for sparse columns */
7570:             for (j = 0; j < nz; j++) *coj++ = cmap[jj[j]];
7571:           }
7572:           ncoo_d += nz;
7573:         }
7574:       }
7575:     }
7576:   }
7577:   if (glob) PetscCall(ISRestoreIndices(glob, &globidx));
7578:   PetscCall(ISDestroy(&glob));
7579:   if (P_oth_l2g) PetscCall(ISLocalToGlobalMappingRestoreIndices(P_oth_l2g, &P_oth_idx));
7580:   PetscCall(ISLocalToGlobalMappingDestroy(&P_oth_l2g));
7581:   /* allocate an array to store all nonzeros (inserted locally or remotely) belonging to this proc */
7582:   PetscCall(PetscSFMalloc(mmdata->sf, mmdata->mtype, ncoo * sizeof(PetscScalar), (void **)&mmdata->coo_v));

7584:   /* set block sizes */
7585:   A = product->A;
7586:   P = product->B;
7587:   switch (ptype) {
7588:   case MATPRODUCT_PtAP:
7589:     PetscCall(MatSetBlockSizes(C, P->cmap->bs, P->cmap->bs));
7590:     break;
7591:   case MATPRODUCT_RARt:
7592:     PetscCall(MatSetBlockSizes(C, P->rmap->bs, P->rmap->bs));
7593:     break;
7594:   case MATPRODUCT_ABC:
7595:     PetscCall(MatSetBlockSizesFromMats(C, A, product->C));
7596:     break;
7597:   case MATPRODUCT_AB:
7598:     PetscCall(MatSetBlockSizesFromMats(C, A, P));
7599:     break;
7600:   case MATPRODUCT_AtB:
7601:     PetscCall(MatSetBlockSizes(C, A->cmap->bs, P->cmap->bs));
7602:     break;
7603:   case MATPRODUCT_ABt:
7604:     PetscCall(MatSetBlockSizes(C, A->rmap->bs, P->rmap->bs));
7605:     break;
7606:   default:
7607:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for ProductType %s", MatProductTypes[ptype]);
7608:   }

7610:   /* preallocate with COO data */
7611:   PetscCall(MatSetPreallocationCOO(C, ncoo, coo_i, coo_j));
7612:   PetscCall(PetscFree2(coo_i, coo_j));
7613:   PetscFunctionReturn(PETSC_SUCCESS);
7614: }

7616: PetscErrorCode MatProductSetFromOptions_MPIAIJBACKEND(Mat mat)
7617: {
7618:   Mat_Product *product = mat->product;
7619: #if defined(PETSC_HAVE_DEVICE)
7620:   PetscBool match  = PETSC_FALSE;
7621:   PetscBool usecpu = PETSC_FALSE;
7622: #else
7623:   PetscBool match = PETSC_TRUE;
7624: #endif

7626:   PetscFunctionBegin;
7627:   MatCheckProduct(mat, 1);
7628: #if defined(PETSC_HAVE_DEVICE)
7629:   if (!product->A->boundtocpu && !product->B->boundtocpu) PetscCall(PetscObjectTypeCompare((PetscObject)product->B, ((PetscObject)product->A)->type_name, &match));
7630:   if (match) { /* we can always fallback to the CPU if requested */
7631:     switch (product->type) {
7632:     case MATPRODUCT_AB:
7633:       if (product->api_user) {
7634:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatMatMult", "Mat");
7635:         PetscCall(PetscOptionsBool("-matmatmult_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
7636:         PetscOptionsEnd();
7637:       } else {
7638:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AB", "Mat");
7639:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
7640:         PetscOptionsEnd();
7641:       }
7642:       break;
7643:     case MATPRODUCT_AtB:
7644:       if (product->api_user) {
7645:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatTransposeMatMult", "Mat");
7646:         PetscCall(PetscOptionsBool("-mattransposematmult_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
7647:         PetscOptionsEnd();
7648:       } else {
7649:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AtB", "Mat");
7650:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
7651:         PetscOptionsEnd();
7652:       }
7653:       break;
7654:     case MATPRODUCT_PtAP:
7655:       if (product->api_user) {
7656:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatPtAP", "Mat");
7657:         PetscCall(PetscOptionsBool("-matptap_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
7658:         PetscOptionsEnd();
7659:       } else {
7660:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_PtAP", "Mat");
7661:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
7662:         PetscOptionsEnd();
7663:       }
7664:       break;
7665:     default:
7666:       break;
7667:     }
7668:     match = (PetscBool)!usecpu;
7669:   }
7670: #endif
7671:   if (match) {
7672:     switch (product->type) {
7673:     case MATPRODUCT_AB:
7674:     case MATPRODUCT_AtB:
7675:     case MATPRODUCT_PtAP:
7676:       mat->ops->productsymbolic = MatProductSymbolic_MPIAIJBACKEND;
7677:       break;
7678:     default:
7679:       break;
7680:     }
7681:   }
7682:   /* fallback to MPIAIJ ops */
7683:   if (!mat->ops->productsymbolic) PetscCall(MatProductSetFromOptions_MPIAIJ(mat));
7684:   PetscFunctionReturn(PETSC_SUCCESS);
7685: }

7687: /*
7688:    Produces a set of block column indices of the matrix row, one for each block represented in the original row

7690:    n - the number of block indices in cc[]
7691:    cc - the block indices (must be large enough to contain the indices)
7692: */
7693: static inline PetscErrorCode MatCollapseRow(Mat Amat, PetscInt row, PetscInt bs, PetscInt *n, PetscInt *cc)
7694: {
7695:   PetscInt        cnt = -1, nidx, j;
7696:   const PetscInt *idx;

7698:   PetscFunctionBegin;
7699:   PetscCall(MatGetRow(Amat, row, &nidx, &idx, NULL));
7700:   if (nidx) {
7701:     cnt     = 0;
7702:     cc[cnt] = idx[0] / bs;
7703:     for (j = 1; j < nidx; j++) {
7704:       if (cc[cnt] < idx[j] / bs) cc[++cnt] = idx[j] / bs;
7705:     }
7706:   }
7707:   PetscCall(MatRestoreRow(Amat, row, &nidx, &idx, NULL));
7708:   *n = cnt + 1;
7709:   PetscFunctionReturn(PETSC_SUCCESS);
7710: }

7712: /*
7713:     Produces a set of block column indices of the matrix block row, one for each block represented in the original set of rows

7715:     ncollapsed - the number of block indices
7716:     collapsed - the block indices (must be large enough to contain the indices)
7717: */
7718: static inline PetscErrorCode MatCollapseRows(Mat Amat, PetscInt start, PetscInt bs, PetscInt *w0, PetscInt *w1, PetscInt *w2, PetscInt *ncollapsed, PetscInt **collapsed)
7719: {
7720:   PetscInt i, nprev, *cprev = w0, ncur = 0, *ccur = w1, *merged = w2, *cprevtmp;

7722:   PetscFunctionBegin;
7723:   PetscCall(MatCollapseRow(Amat, start, bs, &nprev, cprev));
7724:   for (i = start + 1; i < start + bs; i++) {
7725:     PetscCall(MatCollapseRow(Amat, i, bs, &ncur, ccur));
7726:     PetscCall(PetscMergeIntArray(nprev, cprev, ncur, ccur, &nprev, &merged));
7727:     cprevtmp = cprev;
7728:     cprev    = merged;
7729:     merged   = cprevtmp;
7730:   }
7731:   *ncollapsed = nprev;
7732:   if (collapsed) *collapsed = cprev;
7733:   PetscFunctionReturn(PETSC_SUCCESS);
7734: }

7736: /*
7737:  MatCreateGraph_Simple_AIJ - create simple scalar matrix (graph) from potentially blocked matrix

7739:  Input Parameter:
7740:  . Amat - matrix
7741:  - symmetrize - make the result symmetric
7742:  + scale - scale with diagonal

7744:  Output Parameter:
7745:  . a_Gmat - output scalar graph >= 0

7747: */
7748: PETSC_INTERN PetscErrorCode MatCreateGraph_Simple_AIJ(Mat Amat, PetscBool symmetrize, PetscBool scale, PetscReal filter, PetscInt index_size, PetscInt index[], Mat *a_Gmat)
7749: {
7750:   PetscInt  Istart, Iend, Ii, jj, kk, ncols, nloc, NN, MM, bs;
7751:   MPI_Comm  comm;
7752:   Mat       Gmat;
7753:   PetscBool ismpiaij, isseqaij;
7754:   Mat       a, b, c;
7755:   MatType   jtype;

7757:   PetscFunctionBegin;
7758:   PetscCall(PetscObjectGetComm((PetscObject)Amat, &comm));
7759:   PetscCall(MatGetOwnershipRange(Amat, &Istart, &Iend));
7760:   PetscCall(MatGetSize(Amat, &MM, &NN));
7761:   PetscCall(MatGetBlockSize(Amat, &bs));
7762:   nloc = (Iend - Istart) / bs;

7764:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)Amat, MATSEQAIJ, &isseqaij));
7765:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)Amat, MATMPIAIJ, &ismpiaij));
7766:   PetscCheck(isseqaij || ismpiaij, comm, PETSC_ERR_USER, "Require (MPI)AIJ matrix type");

7768:   /* TODO GPU: these calls are potentially expensive if matrices are large and we want to use the GPU */
7769:   /* A solution consists in providing a new API, MatAIJGetCollapsedAIJ, and each class can provide a fast
7770:      implementation */
7771:   if (bs > 1) {
7772:     PetscCall(MatGetType(Amat, &jtype));
7773:     PetscCall(MatCreate(comm, &Gmat));
7774:     PetscCall(MatSetType(Gmat, jtype));
7775:     PetscCall(MatSetSizes(Gmat, nloc, nloc, PETSC_DETERMINE, PETSC_DETERMINE));
7776:     PetscCall(MatSetBlockSizes(Gmat, 1, 1));
7777:     if (isseqaij || ((Mat_MPIAIJ *)Amat->data)->garray) {
7778:       PetscInt  *d_nnz, *o_nnz;
7779:       MatScalar *aa, val, *AA;
7780:       PetscInt  *aj, *ai, *AJ, nc, nmax = 0;

7782:       if (isseqaij) {
7783:         a = Amat;
7784:         b = NULL;
7785:       } else {
7786:         Mat_MPIAIJ *d = (Mat_MPIAIJ *)Amat->data;
7787:         a             = d->A;
7788:         b             = d->B;
7789:       }
7790:       PetscCall(PetscInfo(Amat, "New bs>1 Graph. nloc=%" PetscInt_FMT "\n", nloc));
7791:       PetscCall(PetscMalloc2(nloc, &d_nnz, (isseqaij ? 0 : nloc), &o_nnz));
7792:       for (c = a, kk = 0; c && kk < 2; c = b, kk++) {
7793:         PetscInt       *nnz = (c == a) ? d_nnz : o_nnz;
7794:         const PetscInt *cols1, *cols2;

7796:         for (PetscInt brow = 0, nc1, nc2, ok = 1; brow < nloc * bs; brow += bs) { // block rows
7797:           PetscCall(MatGetRow(c, brow, &nc2, &cols2, NULL));
7798:           nnz[brow / bs] = nc2 / bs;
7799:           if (nc2 % bs) ok = 0;
7800:           if (nnz[brow / bs] > nmax) nmax = nnz[brow / bs];
7801:           for (PetscInt ii = 1; ii < bs; ii++) { // check for non-dense blocks
7802:             PetscCall(MatGetRow(c, brow + ii, &nc1, &cols1, NULL));
7803:             if (nc1 != nc2) ok = 0;
7804:             else {
7805:               for (PetscInt jj = 0; jj < nc1 && ok == 1; jj++) {
7806:                 if (cols1[jj] != cols2[jj]) ok = 0;
7807:                 if (cols1[jj] % bs != jj % bs) ok = 0;
7808:               }
7809:             }
7810:             PetscCall(MatRestoreRow(c, brow + ii, &nc1, &cols1, NULL));
7811:           }
7812:           PetscCall(MatRestoreRow(c, brow, &nc2, &cols2, NULL));
7813:           if (!ok) {
7814:             PetscCall(PetscFree2(d_nnz, o_nnz));
7815:             PetscCall(PetscInfo(Amat, "Found sparse blocks - revert to slow method\n"));
7816:             goto old_bs;
7817:           }
7818:         }
7819:       }
7820:       PetscCall(MatSeqAIJSetPreallocation(Gmat, 0, d_nnz));
7821:       PetscCall(MatMPIAIJSetPreallocation(Gmat, 0, d_nnz, 0, o_nnz));
7822:       PetscCall(PetscFree2(d_nnz, o_nnz));
7823:       PetscCall(PetscMalloc2(nmax, &AA, nmax, &AJ));
7824:       // diag
7825:       for (PetscInt brow = 0, n, grow; brow < nloc * bs; brow += bs) { // block rows
7826:         Mat_SeqAIJ *aseq = (Mat_SeqAIJ *)a->data;

7828:         ai = aseq->i;
7829:         n  = ai[brow + 1] - ai[brow];
7830:         aj = aseq->j + ai[brow];
7831:         for (PetscInt k = 0; k < n; k += bs) {   // block columns
7832:           AJ[k / bs] = aj[k] / bs + Istart / bs; // diag starts at (Istart,Istart)
7833:           val        = 0;
7834:           if (index_size == 0) {
7835:             for (PetscInt ii = 0; ii < bs; ii++) { // rows in block
7836:               aa = aseq->a + ai[brow + ii] + k;
7837:               for (PetscInt jj = 0; jj < bs; jj++) {    // columns in block
7838:                 val += PetscAbs(PetscRealPart(aa[jj])); // a sort of norm
7839:               }
7840:             }
7841:           } else {                                            // use (index,index) value if provided
7842:             for (PetscInt iii = 0; iii < index_size; iii++) { // rows in block
7843:               PetscInt ii = index[iii];
7844:               aa          = aseq->a + ai[brow + ii] + k;
7845:               for (PetscInt jjj = 0; jjj < index_size; jjj++) { // columns in block
7846:                 PetscInt jj = index[jjj];
7847:                 val += PetscAbs(PetscRealPart(aa[jj]));
7848:               }
7849:             }
7850:           }
7851:           PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs (%" PetscInt_FMT ") >= nmax (%" PetscInt_FMT ")", k / bs, nmax);
7852:           AA[k / bs] = val;
7853:         }
7854:         grow = Istart / bs + brow / bs;
7855:         PetscCall(MatSetValues(Gmat, 1, &grow, n / bs, AJ, AA, ADD_VALUES));
7856:       }
7857:       // off-diag
7858:       if (ismpiaij) {
7859:         Mat_MPIAIJ        *aij = (Mat_MPIAIJ *)Amat->data;
7860:         const PetscScalar *vals;
7861:         const PetscInt    *cols, *garray = aij->garray;

7863:         PetscCheck(garray, PETSC_COMM_SELF, PETSC_ERR_USER, "No garray ?");
7864:         for (PetscInt brow = 0, grow; brow < nloc * bs; brow += bs) { // block rows
7865:           PetscCall(MatGetRow(b, brow, &ncols, &cols, NULL));
7866:           for (PetscInt k = 0, cidx = 0; k < ncols; k += bs, cidx++) {
7867:             PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs >= nmax");
7868:             AA[k / bs] = 0;
7869:             AJ[cidx]   = garray[cols[k]] / bs;
7870:           }
7871:           nc = ncols / bs;
7872:           PetscCall(MatRestoreRow(b, brow, &ncols, &cols, NULL));
7873:           if (index_size == 0) {
7874:             for (PetscInt ii = 0; ii < bs; ii++) { // rows in block
7875:               PetscCall(MatGetRow(b, brow + ii, &ncols, &cols, &vals));
7876:               for (PetscInt k = 0; k < ncols; k += bs) {
7877:                 for (PetscInt jj = 0; jj < bs; jj++) { // cols in block
7878:                   PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs (%" PetscInt_FMT ") >= nmax (%" PetscInt_FMT ")", k / bs, nmax);
7879:                   AA[k / bs] += PetscAbs(PetscRealPart(vals[k + jj]));
7880:                 }
7881:               }
7882:               PetscCall(MatRestoreRow(b, brow + ii, &ncols, &cols, &vals));
7883:             }
7884:           } else {                                            // use (index,index) value if provided
7885:             for (PetscInt iii = 0; iii < index_size; iii++) { // rows in block
7886:               PetscInt ii = index[iii];
7887:               PetscCall(MatGetRow(b, brow + ii, &ncols, &cols, &vals));
7888:               for (PetscInt k = 0; k < ncols; k += bs) {
7889:                 for (PetscInt jjj = 0; jjj < index_size; jjj++) { // cols in block
7890:                   PetscInt jj = index[jjj];
7891:                   AA[k / bs] += PetscAbs(PetscRealPart(vals[k + jj]));
7892:                 }
7893:               }
7894:               PetscCall(MatRestoreRow(b, brow + ii, &ncols, &cols, &vals));
7895:             }
7896:           }
7897:           grow = Istart / bs + brow / bs;
7898:           PetscCall(MatSetValues(Gmat, 1, &grow, nc, AJ, AA, ADD_VALUES));
7899:         }
7900:       }
7901:       PetscCall(MatAssemblyBegin(Gmat, MAT_FINAL_ASSEMBLY));
7902:       PetscCall(MatAssemblyEnd(Gmat, MAT_FINAL_ASSEMBLY));
7903:       PetscCall(PetscFree2(AA, AJ));
7904:     } else {
7905:       const PetscScalar *vals;
7906:       const PetscInt    *idx;
7907:       PetscInt          *d_nnz, *o_nnz, *w0, *w1, *w2;
7908:     old_bs:
7909:       /*
7910:        Determine the preallocation needed for the scalar matrix derived from the vector matrix.
7911:        */
7912:       PetscCall(PetscInfo(Amat, "OLD bs>1 CreateGraph\n"));
7913:       PetscCall(PetscMalloc2(nloc, &d_nnz, (isseqaij ? 0 : nloc), &o_nnz));
7914:       if (isseqaij) {
7915:         PetscInt max_d_nnz;

7917:         /*
7918:          Determine exact preallocation count for (sequential) scalar matrix
7919:          */
7920:         PetscCall(MatSeqAIJGetMaxRowNonzeros(Amat, &max_d_nnz));
7921:         max_d_nnz = PetscMin(nloc, bs * max_d_nnz);
7922:         PetscCall(PetscMalloc3(max_d_nnz, &w0, max_d_nnz, &w1, max_d_nnz, &w2));
7923:         for (Ii = 0, jj = 0; Ii < Iend; Ii += bs, jj++) PetscCall(MatCollapseRows(Amat, Ii, bs, w0, w1, w2, &d_nnz[jj], NULL));
7924:         PetscCall(PetscFree3(w0, w1, w2));
7925:       } else if (ismpiaij) {
7926:         Mat             Daij, Oaij;
7927:         const PetscInt *garray;
7928:         PetscInt        max_d_nnz;

7930:         PetscCall(MatMPIAIJGetSeqAIJ(Amat, &Daij, &Oaij, &garray));
7931:         /*
7932:          Determine exact preallocation count for diagonal block portion of scalar matrix
7933:          */
7934:         PetscCall(MatSeqAIJGetMaxRowNonzeros(Daij, &max_d_nnz));
7935:         max_d_nnz = PetscMin(nloc, bs * max_d_nnz);
7936:         PetscCall(PetscMalloc3(max_d_nnz, &w0, max_d_nnz, &w1, max_d_nnz, &w2));
7937:         for (Ii = 0, jj = 0; Ii < Iend - Istart; Ii += bs, jj++) PetscCall(MatCollapseRows(Daij, Ii, bs, w0, w1, w2, &d_nnz[jj], NULL));
7938:         PetscCall(PetscFree3(w0, w1, w2));
7939:         /*
7940:          Over estimate (usually grossly over), preallocation count for off-diagonal portion of scalar matrix
7941:          */
7942:         for (Ii = 0, jj = 0; Ii < Iend - Istart; Ii += bs, jj++) {
7943:           o_nnz[jj] = 0;
7944:           for (kk = 0; kk < bs; kk++) { /* rows that get collapsed to a single row */
7945:             PetscCall(MatGetRow(Oaij, Ii + kk, &ncols, NULL, NULL));
7946:             o_nnz[jj] += ncols;
7947:             PetscCall(MatRestoreRow(Oaij, Ii + kk, &ncols, NULL, NULL));
7948:           }
7949:           if (o_nnz[jj] > (NN / bs - nloc)) o_nnz[jj] = NN / bs - nloc;
7950:         }
7951:       } else SETERRQ(comm, PETSC_ERR_USER, "Require AIJ matrix type");
7952:       /* get scalar copy (norms) of matrix */
7953:       PetscCall(MatSeqAIJSetPreallocation(Gmat, 0, d_nnz));
7954:       PetscCall(MatMPIAIJSetPreallocation(Gmat, 0, d_nnz, 0, o_nnz));
7955:       PetscCall(PetscFree2(d_nnz, o_nnz));
7956:       for (Ii = Istart; Ii < Iend; Ii++) {
7957:         PetscInt dest_row = Ii / bs;

7959:         PetscCall(MatGetRow(Amat, Ii, &ncols, &idx, &vals));
7960:         for (jj = 0; jj < ncols; jj++) {
7961:           PetscInt    dest_col = idx[jj] / bs;
7962:           PetscScalar sv       = PetscAbs(PetscRealPart(vals[jj]));

7964:           PetscCall(MatSetValues(Gmat, 1, &dest_row, 1, &dest_col, &sv, ADD_VALUES));
7965:         }
7966:         PetscCall(MatRestoreRow(Amat, Ii, &ncols, &idx, &vals));
7967:       }
7968:       PetscCall(MatAssemblyBegin(Gmat, MAT_FINAL_ASSEMBLY));
7969:       PetscCall(MatAssemblyEnd(Gmat, MAT_FINAL_ASSEMBLY));
7970:     }
7971:   } else {
7972:     if (symmetrize || filter >= 0 || scale) PetscCall(MatDuplicate(Amat, MAT_COPY_VALUES, &Gmat));
7973:     else {
7974:       Gmat = Amat;
7975:       PetscCall(PetscObjectReference((PetscObject)Gmat));
7976:     }
7977:     if (isseqaij) {
7978:       a = Gmat;
7979:       b = NULL;
7980:     } else {
7981:       Mat_MPIAIJ *d = (Mat_MPIAIJ *)Gmat->data;
7982:       a             = d->A;
7983:       b             = d->B;
7984:     }
7985:     if (filter >= 0 || scale) {
7986:       /* take absolute value of each entry */
7987:       for (c = a, kk = 0; c && kk < 2; c = b, kk++) {
7988:         MatInfo      info;
7989:         PetscScalar *avals;

7991:         PetscCall(MatGetInfo(c, MAT_LOCAL, &info));
7992:         PetscCall(MatSeqAIJGetArray(c, &avals));
7993:         for (int jj = 0; jj < info.nz_used; jj++) avals[jj] = PetscAbsScalar(avals[jj]);
7994:         PetscCall(MatSeqAIJRestoreArray(c, &avals));
7995:       }
7996:     }
7997:   }
7998:   if (symmetrize) {
7999:     PetscBool isset, issym;

8001:     PetscCall(MatIsSymmetricKnown(Amat, &isset, &issym));
8002:     if (!isset || !issym) {
8003:       Mat matTrans;

8005:       PetscCall(MatTranspose(Gmat, MAT_INITIAL_MATRIX, &matTrans));
8006:       PetscCall(MatAXPY(Gmat, 1.0, matTrans, Gmat->structurally_symmetric == PETSC_BOOL3_TRUE ? SAME_NONZERO_PATTERN : DIFFERENT_NONZERO_PATTERN));
8007:       PetscCall(MatDestroy(&matTrans));
8008:     }
8009:     PetscCall(MatSetOption(Gmat, MAT_SYMMETRIC, PETSC_TRUE));
8010:   } else if (Amat != Gmat) PetscCall(MatPropagateSymmetryOptions(Amat, Gmat));
8011:   if (scale) {
8012:     /* scale c for all diagonal values = 1 or -1 */
8013:     Vec diag;

8015:     PetscCall(MatCreateVecs(Gmat, &diag, NULL));
8016:     PetscCall(MatGetDiagonal(Gmat, diag));
8017:     PetscCall(VecReciprocal(diag));
8018:     PetscCall(VecSqrtAbs(diag));
8019:     PetscCall(MatDiagonalScale(Gmat, diag, diag));
8020:     PetscCall(VecDestroy(&diag));
8021:   }
8022:   PetscCall(MatViewFromOptions(Gmat, NULL, "-mat_graph_view"));
8023:   if (filter >= 0) {
8024:     PetscCall(MatFilter(Gmat, filter, PETSC_TRUE, PETSC_TRUE));
8025:     PetscCall(MatViewFromOptions(Gmat, NULL, "-mat_filter_graph_view"));
8026:   }
8027:   *a_Gmat = Gmat;
8028:   PetscFunctionReturn(PETSC_SUCCESS);
8029: }

8031: PETSC_INTERN PetscErrorCode MatGetCurrentMemType_MPIAIJ(Mat A, PetscMemType *memtype)
8032: {
8033:   Mat_MPIAIJ  *mpiaij = (Mat_MPIAIJ *)A->data;
8034:   PetscMemType mD = PETSC_MEMTYPE_HOST, mO = PETSC_MEMTYPE_HOST;

8036:   PetscFunctionBegin;
8037:   if (mpiaij->A) PetscCall(MatGetCurrentMemType(mpiaij->A, &mD));
8038:   if (mpiaij->B) PetscCall(MatGetCurrentMemType(mpiaij->B, &mO));
8039:   *memtype = (mD == mO) ? mD : PETSC_MEMTYPE_HOST;
8040:   PetscFunctionReturn(PETSC_SUCCESS);
8041: }

8043: /*
8044:     Special version for direct calls from Fortran
8045: */

8047: /* Change these macros so can be used in void function */
8048: /* Identical to PetscCallVoid, except it assigns to *_ierr */
8049: #undef PetscCall
8050: #define PetscCall(...) \
8051:   do { \
8052:     PetscErrorCode ierr_msv_mpiaij = __VA_ARGS__; \
8053:     if (PetscUnlikely(ierr_msv_mpiaij)) { \
8054:       *_ierr = PetscError(PETSC_COMM_SELF, __LINE__, PETSC_FUNCTION_NAME, __FILE__, ierr_msv_mpiaij, PETSC_ERROR_REPEAT, " "); \
8055:       return; \
8056:     } \
8057:   } while (0)

8059: #undef SETERRQ
8060: #define SETERRQ(comm, ierr, ...) \
8061:   do { \
8062:     *_ierr = PetscError(comm, __LINE__, PETSC_FUNCTION_NAME, __FILE__, ierr, PETSC_ERROR_INITIAL, __VA_ARGS__); \
8063:     return; \
8064:   } while (0)

8066: #if defined(PETSC_HAVE_FORTRAN_CAPS)
8067:   #define matsetvaluesmpiaij_ MATSETVALUESMPIAIJ
8068: #elif !defined(PETSC_HAVE_FORTRAN_UNDERSCORE)
8069:   #define matsetvaluesmpiaij_ matsetvaluesmpiaij
8070: #else
8071: #endif
8072: PETSC_EXTERN void matsetvaluesmpiaij_(Mat *mmat, PetscInt *mm, const PetscInt im[], PetscInt *mn, const PetscInt in[], const PetscScalar v[], InsertMode *maddv, PetscErrorCode *_ierr)
8073: {
8074:   Mat         mat = *mmat;
8075:   PetscInt    m = *mm, n = *mn;
8076:   InsertMode  addv = *maddv;
8077:   Mat_MPIAIJ *aij  = (Mat_MPIAIJ *)mat->data;
8078:   PetscScalar value;

8080:   MatCheckPreallocated(mat, 1);
8081:   if (mat->insertmode == NOT_SET_VALUES) mat->insertmode = addv;
8082:   else PetscCheck(mat->insertmode == addv, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Cannot mix add values and insert values");
8083:   {
8084:     PetscInt  i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
8085:     PetscInt  cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
8086:     PetscBool roworiented = aij->roworiented;

8088:     /* Some Variables required in the macro */
8089:     Mat         A     = aij->A;
8090:     Mat_SeqAIJ *a     = (Mat_SeqAIJ *)A->data;
8091:     PetscInt   *aimax = a->imax, *ai = a->i, *ailen = a->ilen, *aj = a->j;
8092:     MatScalar  *aa;
8093:     PetscBool   ignorezeroentries = ((a->ignorezeroentries && (addv == ADD_VALUES)) ? PETSC_TRUE : PETSC_FALSE);
8094:     Mat         B                 = aij->B;
8095:     Mat_SeqAIJ *b                 = (Mat_SeqAIJ *)B->data;
8096:     PetscInt   *bimax = b->imax, *bi = b->i, *bilen = b->ilen, *bj = b->j, bm = aij->B->rmap->n, am = aij->A->rmap->n;
8097:     MatScalar  *ba;
8098:     /* This variable below is only for the PETSC_HAVE_VIENNACL or PETSC_HAVE_CUDA cases, but we define it in all cases because we
8099:      * cannot use "#if defined" inside a macro. */
8100:     PETSC_UNUSED PetscBool inserted = PETSC_FALSE;

8102:     PetscInt  *rp1, *rp2, ii, nrow1, nrow2, _i, rmax1, rmax2, N, low1, high1, low2, high2, t, lastcol1, lastcol2;
8103:     PetscInt   nonew = a->nonew;
8104:     MatScalar *ap1, *ap2;

8106:     PetscFunctionBegin;
8107:     PetscCall(MatSeqAIJGetArray(A, &aa));
8108:     PetscCall(MatSeqAIJGetArray(B, &ba));
8109:     for (i = 0; i < m; i++) {
8110:       if (im[i] < 0) continue;
8111:       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);
8112:       if (im[i] >= rstart && im[i] < rend) {
8113:         row      = im[i] - rstart;
8114:         lastcol1 = -1;
8115:         rp1      = aj + ai[row];
8116:         ap1      = aa + ai[row];
8117:         rmax1    = aimax[row];
8118:         nrow1    = ailen[row];
8119:         low1     = 0;
8120:         high1    = nrow1;
8121:         lastcol2 = -1;
8122:         rp2      = bj + bi[row];
8123:         ap2      = ba + bi[row];
8124:         rmax2    = bimax[row];
8125:         nrow2    = bilen[row];
8126:         low2     = 0;
8127:         high2    = nrow2;

8129:         for (j = 0; j < n; j++) {
8130:           if (roworiented) value = v[i * n + j];
8131:           else value = v[i + j * m];
8132:           if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES) && im[i] != in[j]) continue;
8133:           if (in[j] >= cstart && in[j] < cend) {
8134:             col = in[j] - cstart;
8135:             MatSetValues_SeqAIJ_A_Private(row, col, value, addv, im[i], in[j]);
8136:           } else if (in[j] < 0) continue;
8137:           else if (PetscUnlikelyDebug(in[j] >= mat->cmap->N)) {
8138:             SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column too large: col %" PetscInt_FMT " max %" PetscInt_FMT, in[j], mat->cmap->N - 1);
8139:           } else {
8140:             if (mat->was_assembled) {
8141:               if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
8142: #if defined(PETSC_USE_CTABLE)
8143:               PetscCall(PetscHMapIGetWithDefault(aij->colmap, in[j] + 1, 0, &col));
8144:               col--;
8145: #else
8146:               col = aij->colmap[in[j]] - 1;
8147: #endif
8148:               if (col < 0 && !((Mat_SeqAIJ *)aij->A->data)->nonew) {
8149:                 PetscCall(MatDisAssemble_MPIAIJ(mat, PETSC_FALSE));
8150:                 col = in[j];
8151:                 /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
8152:                 B        = aij->B;
8153:                 b        = (Mat_SeqAIJ *)B->data;
8154:                 bimax    = b->imax;
8155:                 bi       = b->i;
8156:                 bilen    = b->ilen;
8157:                 bj       = b->j;
8158:                 rp2      = bj + bi[row];
8159:                 ap2      = ba + bi[row];
8160:                 rmax2    = bimax[row];
8161:                 nrow2    = bilen[row];
8162:                 low2     = 0;
8163:                 high2    = nrow2;
8164:                 bm       = aij->B->rmap->n;
8165:                 ba       = b->a;
8166:                 inserted = PETSC_FALSE;
8167:               }
8168:             } else col = in[j];
8169:             MatSetValues_SeqAIJ_B_Private(row, col, value, addv, im[i], in[j]);
8170:           }
8171:         }
8172:       } else if (!aij->donotstash) {
8173:         if (roworiented) {
8174:           PetscCall(MatStashValuesRow_Private(&mat->stash, im[i], n, in, v + i * n, (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
8175:         } else {
8176:           PetscCall(MatStashValuesCol_Private(&mat->stash, im[i], n, in, v + i, m, (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
8177:         }
8178:       }
8179:     }
8180:     PetscCall(MatSeqAIJRestoreArray(A, &aa));
8181:     PetscCall(MatSeqAIJRestoreArray(B, &ba));
8182:   }
8183:   PetscFunctionReturnVoid();
8184: }

8186: /* Undefining these here since they were redefined from their original definition above! No
8187:  * other PETSc functions should be defined past this point, as it is impossible to recover the
8188:  * original definitions */
8189: #undef PetscCall
8190: #undef SETERRQ