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) && (defined(PETSC_USE_REAL_SINGLE) || defined(PETSC_USE_REAL_DOUBLE))
 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(mat, "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, MPI_C_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, MPI_C_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;
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:       Vec          col, bcol;
1836:       PetscScalar *array;
1837:       PetscInt    *jj, *garray = aij->garray;

1839:       PetscCall(MatCreateVecs(mat, &col, NULL));
1840:       PetscCall(VecSet(col, 0.0));
1841:       PetscCall(VecGetArrayWrite(col, &array));
1842:       v  = amata;
1843:       jj = amat->j;
1844:       for (j = 0; j < amat->nz; j++) array[*jj++] += PetscAbsScalar(*v++);
1845:       PetscCall(VecRestoreArrayWrite(col, &array));
1846:       PetscCall(MatCreateVecs(aij->B, &bcol, NULL));
1847:       PetscCall(VecSet(bcol, 0.0));
1848:       PetscCall(VecGetArrayWrite(bcol, &array));
1849:       v  = bmata;
1850:       jj = bmat->j;
1851:       for (j = 0; j < bmat->nz; j++) array[*jj++] += PetscAbsScalar(*v++);
1852:       PetscCall(VecSetValues(col, aij->B->cmap->n, garray, array, ADD_VALUES));
1853:       PetscCall(VecRestoreArrayWrite(bcol, &array));
1854:       PetscCall(VecDestroy(&bcol));
1855:       PetscCall(VecAssemblyBegin(col));
1856:       PetscCall(VecAssemblyEnd(col));
1857:       PetscCall(VecNorm(col, NORM_INFINITY, norm));
1858:       PetscCall(VecDestroy(&col));
1859:     } else if (type == NORM_INFINITY) { /* max row norm */
1860:       PetscReal ntemp = 0.0;
1861:       for (j = 0; j < aij->A->rmap->n; j++) {
1862:         v   = PetscSafePointerPlusOffset(amata, amat->i[j]);
1863:         sum = 0.0;
1864:         for (i = 0; i < amat->i[j + 1] - amat->i[j]; i++) {
1865:           sum += PetscAbsScalar(*v);
1866:           v++;
1867:         }
1868:         v = PetscSafePointerPlusOffset(bmata, bmat->i[j]);
1869:         for (i = 0; i < bmat->i[j + 1] - bmat->i[j]; i++) {
1870:           sum += PetscAbsScalar(*v);
1871:           v++;
1872:         }
1873:         if (sum > ntemp) ntemp = sum;
1874:       }
1875:       PetscCallMPI(MPIU_Allreduce(&ntemp, norm, 1, MPIU_REAL, MPIU_MAX, PetscObjectComm((PetscObject)mat)));
1876:       PetscCall(PetscLogFlops(PetscMax(amat->nz + bmat->nz - 1, 0)));
1877:     } else SETERRQ(PetscObjectComm((PetscObject)mat), PETSC_ERR_SUP, "No support for two norm");
1878:     PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &amata));
1879:     PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &bmata));
1880:   }
1881:   PetscFunctionReturn(PETSC_SUCCESS);
1882: }

1884: static PetscErrorCode MatTranspose_MPIAIJ(Mat A, MatReuse reuse, Mat *matout)
1885: {
1886:   Mat_MPIAIJ      *a    = (Mat_MPIAIJ *)A->data, *b;
1887:   Mat_SeqAIJ      *Aloc = (Mat_SeqAIJ *)a->A->data, *Bloc = (Mat_SeqAIJ *)a->B->data, *sub_B_diag;
1888:   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;
1889:   const PetscInt  *ai, *aj, *bi, *bj, *B_diag_i;
1890:   Mat              B, A_diag, *B_diag;
1891:   const MatScalar *pbv, *bv;

1893:   PetscFunctionBegin;
1894:   if (reuse == MAT_REUSE_MATRIX) PetscCall(MatTransposeCheckNonzeroState_Private(A, *matout));
1895:   ma = A->rmap->n;
1896:   na = A->cmap->n;
1897:   mb = a->B->rmap->n;
1898:   nb = a->B->cmap->n;
1899:   ai = Aloc->i;
1900:   aj = Aloc->j;
1901:   bi = Bloc->i;
1902:   bj = Bloc->j;
1903:   if (reuse == MAT_INITIAL_MATRIX || *matout == A) {
1904:     PetscInt            *d_nnz, *g_nnz, *o_nnz;
1905:     PetscSFNode         *oloc;
1906:     PETSC_UNUSED PetscSF sf;

1908:     PetscCall(PetscMalloc4(na, &d_nnz, na, &o_nnz, nb, &g_nnz, nb, &oloc));
1909:     /* compute d_nnz for preallocation */
1910:     PetscCall(PetscArrayzero(d_nnz, na));
1911:     for (i = 0; i < ai[ma]; i++) d_nnz[aj[i]]++;
1912:     /* compute local off-diagonal contributions */
1913:     PetscCall(PetscArrayzero(g_nnz, nb));
1914:     for (i = 0; i < bi[ma]; i++) g_nnz[bj[i]]++;
1915:     /* map those to global */
1916:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1917:     PetscCall(PetscSFSetGraphLayout(sf, A->cmap, nb, NULL, PETSC_USE_POINTER, a->garray));
1918:     PetscCall(PetscSFSetFromOptions(sf));
1919:     PetscCall(PetscArrayzero(o_nnz, na));
1920:     PetscCall(PetscSFReduceBegin(sf, MPIU_INT, g_nnz, o_nnz, MPI_SUM));
1921:     PetscCall(PetscSFReduceEnd(sf, MPIU_INT, g_nnz, o_nnz, MPI_SUM));
1922:     PetscCall(PetscSFDestroy(&sf));

1924:     PetscCall(MatCreate(PetscObjectComm((PetscObject)A), &B));
1925:     PetscCall(MatSetSizes(B, A->cmap->n, A->rmap->n, N, M));
1926:     PetscCall(MatSetBlockSizes(B, A->cmap->bs, A->rmap->bs));
1927:     PetscCall(MatSetType(B, ((PetscObject)A)->type_name));
1928:     PetscCall(MatMPIAIJSetPreallocation(B, 0, d_nnz, 0, o_nnz));
1929:     PetscCall(PetscFree4(d_nnz, o_nnz, g_nnz, oloc));
1930:   } else {
1931:     B = *matout;
1932:     PetscCall(MatSetOption(B, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_TRUE));
1933:   }

1935:   b           = (Mat_MPIAIJ *)B->data;
1936:   A_diag      = a->A;
1937:   B_diag      = &b->A;
1938:   sub_B_diag  = (Mat_SeqAIJ *)(*B_diag)->data;
1939:   A_diag_ncol = A_diag->cmap->N;
1940:   B_diag_ilen = sub_B_diag->ilen;
1941:   B_diag_i    = sub_B_diag->i;

1943:   /* Set ilen for diagonal of B */
1944:   for (i = 0; i < A_diag_ncol; i++) B_diag_ilen[i] = B_diag_i[i + 1] - B_diag_i[i];

1946:   /* Transpose the diagonal part of the matrix. In contrast to the off-diagonal part, this can be done
1947:   very quickly (=without using MatSetValues), because all writes are local. */
1948:   PetscCall(MatTransposeSetPrecursor(A_diag, *B_diag));
1949:   PetscCall(MatTranspose(A_diag, MAT_REUSE_MATRIX, B_diag));

1951:   /* copy over the B part */
1952:   PetscCall(PetscMalloc1(bi[mb], &cols));
1953:   PetscCall(MatSeqAIJGetArrayRead(a->B, &bv));
1954:   pbv = bv;
1955:   row = A->rmap->rstart;
1956:   for (i = 0; i < bi[mb]; i++) cols[i] = a->garray[bj[i]];
1957:   cols_tmp = cols;
1958:   for (i = 0; i < mb; i++) {
1959:     ncol = bi[i + 1] - bi[i];
1960:     PetscCall(MatSetValues(B, ncol, cols_tmp, 1, &row, pbv, INSERT_VALUES));
1961:     row++;
1962:     if (pbv) pbv += ncol;
1963:     if (cols_tmp) cols_tmp += ncol;
1964:   }
1965:   PetscCall(PetscFree(cols));
1966:   PetscCall(MatSeqAIJRestoreArrayRead(a->B, &bv));

1968:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
1969:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
1970:   if (reuse == MAT_INITIAL_MATRIX || reuse == MAT_REUSE_MATRIX) {
1971:     *matout = B;
1972:   } else {
1973:     PetscCall(MatHeaderMerge(A, &B));
1974:   }
1975:   PetscFunctionReturn(PETSC_SUCCESS);
1976: }

1978: static PetscErrorCode MatDiagonalScale_MPIAIJ(Mat mat, Vec ll, Vec rr)
1979: {
1980:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
1981:   Mat         a = aij->A, b = aij->B;
1982:   PetscInt    s1, s2, s3;

1984:   PetscFunctionBegin;
1985:   PetscCall(MatGetLocalSize(mat, &s2, &s3));
1986:   if (rr) {
1987:     PetscCall(VecGetLocalSize(rr, &s1));
1988:     PetscCheck(s1 == s3, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "right vector non-conforming local size");
1989:     /* Overlap communication with computation. */
1990:     PetscCall(VecScatterBegin(aij->Mvctx, rr, aij->lvec, INSERT_VALUES, SCATTER_FORWARD));
1991:   }
1992:   if (ll) {
1993:     PetscCall(VecGetLocalSize(ll, &s1));
1994:     PetscCheck(s1 == s2, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "left vector non-conforming local size");
1995:     PetscUseTypeMethod(b, diagonalscale, ll, NULL);
1996:   }
1997:   /* scale  the diagonal block */
1998:   PetscUseTypeMethod(a, diagonalscale, ll, rr);

2000:   if (rr) {
2001:     /* Do a scatter end and then right scale the off-diagonal block */
2002:     PetscCall(VecScatterEnd(aij->Mvctx, rr, aij->lvec, INSERT_VALUES, SCATTER_FORWARD));
2003:     PetscUseTypeMethod(b, diagonalscale, NULL, aij->lvec);
2004:   }
2005:   PetscFunctionReturn(PETSC_SUCCESS);
2006: }

2008: static PetscErrorCode MatSetUnfactored_MPIAIJ(Mat A)
2009: {
2010:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2012:   PetscFunctionBegin;
2013:   PetscCall(MatSetUnfactored(a->A));
2014:   PetscFunctionReturn(PETSC_SUCCESS);
2015: }

2017: static PetscErrorCode MatEqual_MPIAIJ(Mat A, Mat B, PetscBool *flag)
2018: {
2019:   Mat_MPIAIJ *matB = (Mat_MPIAIJ *)B->data, *matA = (Mat_MPIAIJ *)A->data;
2020:   Mat         a, b, c, d;
2021:   PetscBool   flg;

2023:   PetscFunctionBegin;
2024:   a = matA->A;
2025:   b = matA->B;
2026:   c = matB->A;
2027:   d = matB->B;

2029:   PetscCall(MatEqual(a, c, &flg));
2030:   if (flg) PetscCall(MatEqual(b, d, &flg));
2031:   PetscCallMPI(MPIU_Allreduce(&flg, flag, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)A)));
2032:   PetscFunctionReturn(PETSC_SUCCESS);
2033: }

2035: static PetscErrorCode MatCopy_MPIAIJ(Mat A, Mat B, MatStructure str)
2036: {
2037:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
2038:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;

2040:   PetscFunctionBegin;
2041:   /* If the two matrices don't have the same copy implementation, they aren't compatible for fast copy. */
2042:   if ((str != SAME_NONZERO_PATTERN) || (A->ops->copy != B->ops->copy)) {
2043:     /* because of the column compression in the off-processor part of the matrix a->B,
2044:        the number of columns in a->B and b->B may be different, hence we cannot call
2045:        the MatCopy() directly on the two parts. If need be, we can provide a more
2046:        efficient copy than the MatCopy_Basic() by first uncompressing the a->B matrices
2047:        then copying the submatrices */
2048:     PetscCall(MatCopy_Basic(A, B, str));
2049:   } else {
2050:     PetscCall(MatCopy(a->A, b->A, str));
2051:     PetscCall(MatCopy(a->B, b->B, str));
2052:   }
2053:   PetscCall(PetscObjectStateIncrease((PetscObject)B));
2054:   PetscFunctionReturn(PETSC_SUCCESS);
2055: }

2057: /*
2058:    Computes the number of nonzeros per row needed for preallocation when X and Y
2059:    have different nonzero structure.
2060: */
2061: 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)
2062: {
2063:   PetscInt i, j, k, nzx, nzy;

2065:   PetscFunctionBegin;
2066:   /* Set the number of nonzeros in the new matrix */
2067:   for (i = 0; i < m; i++) {
2068:     const PetscInt *xjj = PetscSafePointerPlusOffset(xj, xi[i]), *yjj = PetscSafePointerPlusOffset(yj, yi[i]);
2069:     nzx    = xi[i + 1] - xi[i];
2070:     nzy    = yi[i + 1] - yi[i];
2071:     nnz[i] = 0;
2072:     for (j = 0, k = 0; j < nzx; j++) {                                /* Point in X */
2073:       for (; k < nzy && yltog[yjj[k]] < xltog[xjj[j]]; k++) nnz[i]++; /* Catch up to X */
2074:       if (k < nzy && yltog[yjj[k]] == xltog[xjj[j]]) k++;             /* Skip duplicate */
2075:       nnz[i]++;
2076:     }
2077:     for (; k < nzy; k++) nnz[i]++;
2078:   }
2079:   PetscFunctionReturn(PETSC_SUCCESS);
2080: }

2082: /* This is the same as MatAXPYGetPreallocation_SeqAIJ, except that the local-to-global map is provided */
2083: static PetscErrorCode MatAXPYGetPreallocation_MPIAIJ(Mat Y, const PetscInt *yltog, Mat X, const PetscInt *xltog, PetscInt *nnz)
2084: {
2085:   PetscInt    m = Y->rmap->N;
2086:   Mat_SeqAIJ *x = (Mat_SeqAIJ *)X->data;
2087:   Mat_SeqAIJ *y = (Mat_SeqAIJ *)Y->data;

2089:   PetscFunctionBegin;
2090:   PetscCall(MatAXPYGetPreallocation_MPIX_private(m, x->i, x->j, xltog, y->i, y->j, yltog, nnz));
2091:   PetscFunctionReturn(PETSC_SUCCESS);
2092: }

2094: static PetscErrorCode MatAXPY_MPIAIJ(Mat Y, PetscScalar a, Mat X, MatStructure str)
2095: {
2096:   Mat_MPIAIJ *xx = (Mat_MPIAIJ *)X->data, *yy = (Mat_MPIAIJ *)Y->data;

2098:   PetscFunctionBegin;
2099:   if (str == SAME_NONZERO_PATTERN) {
2100:     PetscCall(MatAXPY(yy->A, a, xx->A, str));
2101:     PetscCall(MatAXPY(yy->B, a, xx->B, str));
2102:   } else if (str == SUBSET_NONZERO_PATTERN) { /* nonzeros of X is a subset of Y's */
2103:     PetscCall(MatAXPY_Basic(Y, a, X, str));
2104:   } else {
2105:     Mat       B;
2106:     PetscInt *nnz_d, *nnz_o;

2108:     PetscCall(PetscMalloc1(yy->A->rmap->N, &nnz_d));
2109:     PetscCall(PetscMalloc1(yy->B->rmap->N, &nnz_o));
2110:     PetscCall(MatCreate(PetscObjectComm((PetscObject)Y), &B));
2111:     PetscCall(PetscObjectSetName((PetscObject)B, ((PetscObject)Y)->name));
2112:     PetscCall(MatSetLayouts(B, Y->rmap, Y->cmap));
2113:     PetscCall(MatSetType(B, ((PetscObject)Y)->type_name));
2114:     PetscCall(MatAXPYGetPreallocation_SeqAIJ(yy->A, xx->A, nnz_d));
2115:     PetscCall(MatAXPYGetPreallocation_MPIAIJ(yy->B, yy->garray, xx->B, xx->garray, nnz_o));
2116:     PetscCall(MatMPIAIJSetPreallocation(B, 0, nnz_d, 0, nnz_o));
2117:     PetscCall(MatAXPY_BasicWithPreallocation(B, Y, a, X, str));
2118:     PetscCall(MatHeaderMerge(Y, &B));
2119:     PetscCall(PetscFree(nnz_d));
2120:     PetscCall(PetscFree(nnz_o));
2121:   }
2122:   PetscFunctionReturn(PETSC_SUCCESS);
2123: }

2125: PETSC_INTERN PetscErrorCode MatConjugate_SeqAIJ(Mat);

2127: static PetscErrorCode MatConjugate_MPIAIJ(Mat mat)
2128: {
2129:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2131:   PetscFunctionBegin;
2132:   PetscCall(MatConjugate_SeqAIJ(aij->A));
2133:   PetscCall(MatConjugate_SeqAIJ(aij->B));
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 MatInvertVariableBlockDiagonal_MPIAIJ(Mat A, PetscInt nblocks, const PetscInt *bsizes, PetscScalar *diag)
2690: {
2691:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2693:   PetscFunctionBegin;
2694:   PetscCall(MatInvertVariableBlockDiagonal(a->A, nblocks, bsizes, diag));
2695:   PetscFunctionReturn(PETSC_SUCCESS);
2696: }

2698: static PetscErrorCode MatEliminateZeros_MPIAIJ(Mat A, PetscBool keep)
2699: {
2700:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2702:   PetscFunctionBegin;
2703:   PetscCall(MatEliminateZeros_SeqAIJ(a->A, keep));        // possibly keep zero diagonal coefficients
2704:   PetscCall(MatEliminateZeros_SeqAIJ(a->B, PETSC_FALSE)); // never keep zero diagonal coefficients
2705:   PetscFunctionReturn(PETSC_SUCCESS);
2706: }

2708: static struct _MatOps MatOps_Values = {MatSetValues_MPIAIJ,
2709:                                        MatGetRow_MPIAIJ,
2710:                                        MatRestoreRow_MPIAIJ,
2711:                                        MatMult_MPIAIJ,
2712:                                        /* 4*/ MatMultAdd_MPIAIJ,
2713:                                        MatMultTranspose_MPIAIJ,
2714:                                        MatMultTransposeAdd_MPIAIJ,
2715:                                        NULL,
2716:                                        NULL,
2717:                                        NULL,
2718:                                        /*10*/ NULL,
2719:                                        NULL,
2720:                                        NULL,
2721:                                        MatSOR_MPIAIJ,
2722:                                        MatTranspose_MPIAIJ,
2723:                                        /*15*/ MatGetInfo_MPIAIJ,
2724:                                        MatEqual_MPIAIJ,
2725:                                        MatGetDiagonal_MPIAIJ,
2726:                                        MatDiagonalScale_MPIAIJ,
2727:                                        MatNorm_MPIAIJ,
2728:                                        /*20*/ MatAssemblyBegin_MPIAIJ,
2729:                                        MatAssemblyEnd_MPIAIJ,
2730:                                        MatSetOption_MPIAIJ,
2731:                                        MatZeroEntries_MPIAIJ,
2732:                                        /*24*/ MatZeroRows_MPIAIJ,
2733:                                        NULL,
2734:                                        NULL,
2735:                                        NULL,
2736:                                        NULL,
2737:                                        /*29*/ MatSetUp_MPI_Hash,
2738:                                        NULL,
2739:                                        NULL,
2740:                                        MatGetDiagonalBlock_MPIAIJ,
2741:                                        NULL,
2742:                                        /*34*/ MatDuplicate_MPIAIJ,
2743:                                        NULL,
2744:                                        NULL,
2745:                                        NULL,
2746:                                        NULL,
2747:                                        /*39*/ MatAXPY_MPIAIJ,
2748:                                        MatCreateSubMatrices_MPIAIJ,
2749:                                        MatIncreaseOverlap_MPIAIJ,
2750:                                        MatGetValues_MPIAIJ,
2751:                                        MatCopy_MPIAIJ,
2752:                                        /*44*/ MatGetRowMax_MPIAIJ,
2753:                                        MatScale_MPIAIJ,
2754:                                        MatShift_MPIAIJ,
2755:                                        MatDiagonalSet_MPIAIJ,
2756:                                        MatZeroRowsColumns_MPIAIJ,
2757:                                        /*49*/ MatSetRandom_MPIAIJ,
2758:                                        MatGetRowIJ_MPIAIJ,
2759:                                        MatRestoreRowIJ_MPIAIJ,
2760:                                        NULL,
2761:                                        NULL,
2762:                                        /*54*/ MatFDColoringCreate_MPIXAIJ,
2763:                                        NULL,
2764:                                        MatSetUnfactored_MPIAIJ,
2765:                                        MatPermute_MPIAIJ,
2766:                                        NULL,
2767:                                        /*59*/ MatCreateSubMatrix_MPIAIJ,
2768:                                        MatDestroy_MPIAIJ,
2769:                                        MatView_MPIAIJ,
2770:                                        NULL,
2771:                                        NULL,
2772:                                        /*64*/ MatMatMatMultNumeric_MPIAIJ_MPIAIJ_MPIAIJ,
2773:                                        NULL,
2774:                                        NULL,
2775:                                        NULL,
2776:                                        MatGetRowMaxAbs_MPIAIJ,
2777:                                        /*69*/ MatGetRowMinAbs_MPIAIJ,
2778:                                        NULL,
2779:                                        NULL,
2780:                                        MatFDColoringApply_AIJ,
2781:                                        MatSetFromOptions_MPIAIJ,
2782:                                        MatFindZeroDiagonals_MPIAIJ,
2783:                                        /*75*/ NULL,
2784:                                        NULL,
2785:                                        NULL,
2786:                                        MatLoad_MPIAIJ,
2787:                                        NULL,
2788:                                        /*80*/ NULL,
2789:                                        NULL,
2790:                                        NULL,
2791:                                        /*83*/ NULL,
2792:                                        NULL,
2793:                                        MatMatMultNumeric_MPIAIJ_MPIAIJ,
2794:                                        MatPtAPNumeric_MPIAIJ_MPIAIJ,
2795:                                        NULL,
2796:                                        NULL,
2797:                                        /*89*/ MatBindToCPU_MPIAIJ,
2798:                                        MatProductSetFromOptions_MPIAIJ,
2799:                                        NULL,
2800:                                        NULL,
2801:                                        MatConjugate_MPIAIJ,
2802:                                        /*94*/ NULL,
2803:                                        MatSetValuesRow_MPIAIJ,
2804:                                        MatRealPart_MPIAIJ,
2805:                                        MatImaginaryPart_MPIAIJ,
2806:                                        NULL,
2807:                                        /*99*/ NULL,
2808:                                        NULL,
2809:                                        NULL,
2810:                                        MatGetRowMin_MPIAIJ,
2811:                                        NULL,
2812:                                        /*104*/ MatGetSeqNonzeroStructure_MPIAIJ,
2813:                                        NULL,
2814:                                        MatGetGhosts_MPIAIJ,
2815:                                        NULL,
2816:                                        NULL,
2817:                                        /*109*/ MatMultDiagonalBlock_MPIAIJ,
2818:                                        NULL,
2819:                                        NULL,
2820:                                        NULL,
2821:                                        MatGetMultiProcBlock_MPIAIJ,
2822:                                        /*114*/ MatFindNonzeroRows_MPIAIJ,
2823:                                        MatGetColumnReductions_MPIAIJ,
2824:                                        MatInvertBlockDiagonal_MPIAIJ,
2825:                                        MatInvertVariableBlockDiagonal_MPIAIJ,
2826:                                        MatCreateSubMatricesMPI_MPIAIJ,
2827:                                        /*119*/ NULL,
2828:                                        NULL,
2829:                                        MatTransposeMatMultNumeric_MPIAIJ_MPIAIJ,
2830:                                        NULL,
2831:                                        NULL,
2832:                                        /*124*/ NULL,
2833:                                        NULL,
2834:                                        MatSetBlockSizes_MPIAIJ,
2835:                                        NULL,
2836:                                        MatFDColoringSetUp_MPIXAIJ,
2837:                                        /*129*/ MatFindOffBlockDiagonalEntries_MPIAIJ,
2838:                                        MatCreateMPIMatConcatenateSeqMat_MPIAIJ,
2839:                                        NULL,
2840:                                        NULL,
2841:                                        NULL,
2842:                                        /*134*/ MatCreateGraph_Simple_AIJ,
2843:                                        NULL,
2844:                                        MatEliminateZeros_MPIAIJ,
2845:                                        MatGetRowSumAbs_MPIAIJ,
2846:                                        NULL,
2847:                                        /*139*/ NULL,
2848:                                        NULL,
2849:                                        MatCopyHashToXAIJ_MPI_Hash,
2850:                                        MatGetCurrentMemType_MPIAIJ,
2851:                                        NULL};

2853: static PetscErrorCode MatStoreValues_MPIAIJ(Mat mat)
2854: {
2855:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2857:   PetscFunctionBegin;
2858:   PetscCall(MatStoreValues(aij->A));
2859:   PetscCall(MatStoreValues(aij->B));
2860:   PetscFunctionReturn(PETSC_SUCCESS);
2861: }

2863: static PetscErrorCode MatRetrieveValues_MPIAIJ(Mat mat)
2864: {
2865:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2867:   PetscFunctionBegin;
2868:   PetscCall(MatRetrieveValues(aij->A));
2869:   PetscCall(MatRetrieveValues(aij->B));
2870:   PetscFunctionReturn(PETSC_SUCCESS);
2871: }

2873: PetscErrorCode MatMPIAIJSetPreallocation_MPIAIJ(Mat B, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[])
2874: {
2875:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;
2876:   PetscMPIInt size;

2878:   PetscFunctionBegin;
2879:   if (B->hash_active) {
2880:     B->ops[0]      = b->cops;
2881:     B->hash_active = PETSC_FALSE;
2882:   }
2883:   PetscCall(PetscLayoutSetUp(B->rmap));
2884:   PetscCall(PetscLayoutSetUp(B->cmap));

2886: #if defined(PETSC_USE_CTABLE)
2887:   PetscCall(PetscHMapIDestroy(&b->colmap));
2888: #else
2889:   PetscCall(PetscFree(b->colmap));
2890: #endif
2891:   PetscCall(PetscFree(b->garray));
2892:   PetscCall(VecDestroy(&b->lvec));
2893:   PetscCall(VecScatterDestroy(&b->Mvctx));

2895:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)B), &size));

2897:   MatSeqXAIJGetOptions_Private(b->B);
2898:   PetscCall(MatDestroy(&b->B));
2899:   PetscCall(MatCreate(PETSC_COMM_SELF, &b->B));
2900:   PetscCall(MatSetSizes(b->B, B->rmap->n, size > 1 ? B->cmap->N : 0, B->rmap->n, size > 1 ? B->cmap->N : 0));
2901:   PetscCall(MatSetBlockSizesFromMats(b->B, B, B));
2902:   PetscCall(MatSetType(b->B, MATSEQAIJ));
2903:   MatSeqXAIJRestoreOptions_Private(b->B);

2905:   MatSeqXAIJGetOptions_Private(b->A);
2906:   PetscCall(MatDestroy(&b->A));
2907:   PetscCall(MatCreate(PETSC_COMM_SELF, &b->A));
2908:   PetscCall(MatSetSizes(b->A, B->rmap->n, B->cmap->n, B->rmap->n, B->cmap->n));
2909:   PetscCall(MatSetBlockSizesFromMats(b->A, B, B));
2910:   PetscCall(MatSetType(b->A, MATSEQAIJ));
2911:   MatSeqXAIJRestoreOptions_Private(b->A);

2913:   PetscCall(MatSeqAIJSetPreallocation(b->A, d_nz, d_nnz));
2914:   PetscCall(MatSeqAIJSetPreallocation(b->B, o_nz, o_nnz));
2915:   B->preallocated  = PETSC_TRUE;
2916:   B->was_assembled = PETSC_FALSE;
2917:   B->assembled     = PETSC_FALSE;
2918:   PetscFunctionReturn(PETSC_SUCCESS);
2919: }

2921: static PetscErrorCode MatResetPreallocation_MPIAIJ(Mat B)
2922: {
2923:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;
2924:   PetscBool   ondiagreset, offdiagreset, memoryreset;

2926:   PetscFunctionBegin;
2928:   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()");
2929:   if (B->num_ass == 0) PetscFunctionReturn(PETSC_SUCCESS);

2931:   PetscCall(MatResetPreallocation_SeqAIJ_Private(b->A, &ondiagreset));
2932:   PetscCall(MatResetPreallocation_SeqAIJ_Private(b->B, &offdiagreset));
2933:   memoryreset = (PetscBool)(ondiagreset || offdiagreset);
2934:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &memoryreset, 1, MPI_C_BOOL, MPI_LOR, PetscObjectComm((PetscObject)B)));
2935:   if (!memoryreset) PetscFunctionReturn(PETSC_SUCCESS);

2937:   PetscCall(PetscLayoutSetUp(B->rmap));
2938:   PetscCall(PetscLayoutSetUp(B->cmap));
2939:   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");
2940:   PetscCall(MatDisAssemble_MPIAIJ(B, PETSC_TRUE));
2941:   PetscCall(VecScatterDestroy(&b->Mvctx));

2943:   B->preallocated  = PETSC_TRUE;
2944:   B->was_assembled = PETSC_FALSE;
2945:   B->assembled     = PETSC_FALSE;
2946:   /* Log that the state of this object has changed; this will help guarantee that preconditioners get re-setup */
2947:   PetscCall(PetscObjectStateIncrease((PetscObject)B));
2948:   PetscFunctionReturn(PETSC_SUCCESS);
2949: }

2951: PetscErrorCode MatDuplicate_MPIAIJ(Mat matin, MatDuplicateOption cpvalues, Mat *newmat)
2952: {
2953:   Mat         mat;
2954:   Mat_MPIAIJ *a, *oldmat = (Mat_MPIAIJ *)matin->data;

2956:   PetscFunctionBegin;
2957:   *newmat = NULL;
2958:   PetscCall(MatCreate(PetscObjectComm((PetscObject)matin), &mat));
2959:   PetscCall(MatSetSizes(mat, matin->rmap->n, matin->cmap->n, matin->rmap->N, matin->cmap->N));
2960:   PetscCall(MatSetBlockSizesFromMats(mat, matin, matin));
2961:   PetscCall(MatSetType(mat, ((PetscObject)matin)->type_name));
2962:   a = (Mat_MPIAIJ *)mat->data;

2964:   mat->factortype = matin->factortype;
2965:   mat->assembled  = matin->assembled;
2966:   mat->insertmode = NOT_SET_VALUES;

2968:   a->size         = oldmat->size;
2969:   a->rank         = oldmat->rank;
2970:   a->donotstash   = oldmat->donotstash;
2971:   a->roworiented  = oldmat->roworiented;
2972:   a->rowindices   = NULL;
2973:   a->rowvalues    = NULL;
2974:   a->getrowactive = PETSC_FALSE;

2976:   PetscCall(PetscLayoutReference(matin->rmap, &mat->rmap));
2977:   PetscCall(PetscLayoutReference(matin->cmap, &mat->cmap));
2978:   if (matin->hash_active) {
2979:     PetscCall(MatSetUp(mat));
2980:   } else {
2981:     mat->preallocated = matin->preallocated;
2982:     if (oldmat->colmap) {
2983: #if defined(PETSC_USE_CTABLE)
2984:       PetscCall(PetscHMapIDuplicate(oldmat->colmap, &a->colmap));
2985: #else
2986:       PetscCall(PetscMalloc1(mat->cmap->N, &a->colmap));
2987:       PetscCall(PetscArraycpy(a->colmap, oldmat->colmap, mat->cmap->N));
2988: #endif
2989:     } else a->colmap = NULL;
2990:     if (oldmat->garray) {
2991:       PetscInt len;
2992:       len = oldmat->B->cmap->n;
2993:       PetscCall(PetscMalloc1(len, &a->garray));
2994:       if (len) PetscCall(PetscArraycpy(a->garray, oldmat->garray, len));
2995:     } else a->garray = NULL;

2997:     /* It may happen MatDuplicate is called with a non-assembled matrix
2998:       In fact, MatDuplicate only requires the matrix to be preallocated
2999:       This may happen inside a DMCreateMatrix_Shell */
3000:     if (oldmat->lvec) PetscCall(VecDuplicate(oldmat->lvec, &a->lvec));
3001:     if (oldmat->Mvctx) {
3002:       a->Mvctx = oldmat->Mvctx;
3003:       PetscCall(PetscObjectReference((PetscObject)oldmat->Mvctx));
3004:     }
3005:     PetscCall(MatDuplicate(oldmat->A, cpvalues, &a->A));
3006:     PetscCall(MatDuplicate(oldmat->B, cpvalues, &a->B));
3007:   }
3008:   PetscCall(PetscFunctionListDuplicate(((PetscObject)matin)->qlist, &((PetscObject)mat)->qlist));
3009:   *newmat = mat;
3010:   PetscFunctionReturn(PETSC_SUCCESS);
3011: }

3013: PetscErrorCode MatLoad_MPIAIJ(Mat newMat, PetscViewer viewer)
3014: {
3015:   PetscBool isbinary, ishdf5;

3017:   PetscFunctionBegin;
3020:   /* force binary viewer to load .info file if it has not yet done so */
3021:   PetscCall(PetscViewerSetUp(viewer));
3022:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
3023:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERHDF5, &ishdf5));
3024:   if (isbinary) {
3025:     PetscCall(MatLoad_MPIAIJ_Binary(newMat, viewer));
3026:   } else if (ishdf5) {
3027: #if defined(PETSC_HAVE_HDF5)
3028:     PetscCall(MatLoad_AIJ_HDF5(newMat, viewer));
3029: #else
3030:     SETERRQ(PetscObjectComm((PetscObject)newMat), PETSC_ERR_SUP, "HDF5 not supported in this build.\nPlease reconfigure using --download-hdf5");
3031: #endif
3032:   } else {
3033:     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);
3034:   }
3035:   PetscFunctionReturn(PETSC_SUCCESS);
3036: }

3038: PetscErrorCode MatLoad_MPIAIJ_Binary(Mat mat, PetscViewer viewer)
3039: {
3040:   PetscInt     header[4], M, N, m, nz, rows, cols, sum, i;
3041:   PetscInt    *rowidxs, *colidxs;
3042:   PetscScalar *matvals;

3044:   PetscFunctionBegin;
3045:   PetscCall(PetscViewerSetUp(viewer));

3047:   /* read in matrix header */
3048:   PetscCall(PetscViewerBinaryRead(viewer, header, 4, NULL, PETSC_INT));
3049:   PetscCheck(header[0] == MAT_FILE_CLASSID, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Not a matrix object in file");
3050:   M  = header[1];
3051:   N  = header[2];
3052:   nz = header[3];
3053:   PetscCheck(M >= 0, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Matrix row size (%" PetscInt_FMT ") in file is negative", M);
3054:   PetscCheck(N >= 0, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Matrix column size (%" PetscInt_FMT ") in file is negative", N);
3055:   PetscCheck(nz >= 0, PETSC_COMM_SELF, PETSC_ERR_FILE_UNEXPECTED, "Matrix stored in special format on disk, cannot load as MPIAIJ");

3057:   /* set block sizes from the viewer's .info file */
3058:   PetscCall(MatLoad_Binary_BlockSizes(mat, viewer));
3059:   /* set global sizes if not set already */
3060:   if (mat->rmap->N < 0) mat->rmap->N = M;
3061:   if (mat->cmap->N < 0) mat->cmap->N = N;
3062:   PetscCall(PetscLayoutSetUp(mat->rmap));
3063:   PetscCall(PetscLayoutSetUp(mat->cmap));

3065:   /* check if the matrix sizes are correct */
3066:   PetscCall(MatGetSize(mat, &rows, &cols));
3067:   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);

3069:   /* read in row lengths and build row indices */
3070:   PetscCall(MatGetLocalSize(mat, &m, NULL));
3071:   PetscCall(PetscMalloc1(m + 1, &rowidxs));
3072:   PetscCall(PetscViewerBinaryReadAll(viewer, rowidxs + 1, m, PETSC_DECIDE, M, PETSC_INT));
3073:   rowidxs[0] = 0;
3074:   for (i = 0; i < m; i++) rowidxs[i + 1] += rowidxs[i];
3075:   if (nz != PETSC_INT_MAX) {
3076:     PetscCallMPI(MPIU_Allreduce(&rowidxs[m], &sum, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)viewer)));
3077:     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);
3078:   }

3080:   /* read in column indices and matrix values */
3081:   PetscCall(PetscMalloc2(rowidxs[m], &colidxs, rowidxs[m], &matvals));
3082:   PetscCall(PetscViewerBinaryReadAll(viewer, colidxs, rowidxs[m], PETSC_DETERMINE, PETSC_DETERMINE, PETSC_INT));
3083:   PetscCall(PetscViewerBinaryReadAll(viewer, matvals, rowidxs[m], PETSC_DETERMINE, PETSC_DETERMINE, PETSC_SCALAR));
3084:   /* store matrix indices and values */
3085:   PetscCall(MatMPIAIJSetPreallocationCSR(mat, rowidxs, colidxs, matvals));
3086:   PetscCall(PetscFree(rowidxs));
3087:   PetscCall(PetscFree2(colidxs, matvals));
3088:   PetscFunctionReturn(PETSC_SUCCESS);
3089: }

3091: /* Not scalable because of ISAllGather() unless getting all columns. */
3092: static PetscErrorCode ISGetSeqIS_Private(Mat mat, IS iscol, IS *isseq)
3093: {
3094:   IS          iscol_local;
3095:   PetscBool   isstride;
3096:   PetscMPIInt gisstride = 0;

3098:   PetscFunctionBegin;
3099:   /* check if we are grabbing all columns*/
3100:   PetscCall(PetscObjectTypeCompare((PetscObject)iscol, ISSTRIDE, &isstride));

3102:   if (isstride) {
3103:     PetscInt start, len, mstart, mlen;
3104:     PetscCall(ISStrideGetInfo(iscol, &start, NULL));
3105:     PetscCall(ISGetLocalSize(iscol, &len));
3106:     PetscCall(MatGetOwnershipRangeColumn(mat, &mstart, &mlen));
3107:     if (mstart == start && mlen - mstart == len) gisstride = 1;
3108:   }

3110:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &gisstride, 1, MPI_INT, MPI_MIN, PetscObjectComm((PetscObject)mat)));
3111:   if (gisstride) {
3112:     PetscInt N;
3113:     PetscCall(MatGetSize(mat, NULL, &N));
3114:     PetscCall(ISCreateStride(PETSC_COMM_SELF, N, 0, 1, &iscol_local));
3115:     PetscCall(ISSetIdentity(iscol_local));
3116:     PetscCall(PetscInfo(mat, "Optimizing for obtaining all columns of the matrix; skipping ISAllGather()\n"));
3117:   } else {
3118:     PetscInt cbs;
3119:     PetscCall(ISGetBlockSize(iscol, &cbs));
3120:     PetscCall(ISAllGather(iscol, &iscol_local));
3121:     PetscCall(ISSetBlockSize(iscol_local, cbs));
3122:   }

3124:   *isseq = iscol_local;
3125:   PetscFunctionReturn(PETSC_SUCCESS);
3126: }

3128: /*
3129:  Used by MatCreateSubMatrix_MPIAIJ_SameRowColDist() to avoid ISAllGather() and global size of iscol_local
3130:  (see MatCreateSubMatrix_MPIAIJ_nonscalable)

3132:  Input Parameters:
3133: +   mat - matrix
3134: .   isrow - parallel row index set; its local indices are a subset of local columns of `mat`,
3135:            i.e., mat->rstart <= isrow[i] < mat->rend
3136: -   iscol - parallel column index set; its local indices are a subset of local columns of `mat`,
3137:            i.e., mat->cstart <= iscol[i] < mat->cend

3139:  Output Parameters:
3140: +   isrow_d - sequential row index set for retrieving mat->A
3141: .   iscol_d - sequential  column index set for retrieving mat->A
3142: .   iscol_o - sequential column index set for retrieving mat->B
3143: -   garray - column map; garray[i] indicates global location of iscol_o[i] in `iscol`
3144:  */
3145: static PetscErrorCode ISGetSeqIS_SameColDist_Private(Mat mat, IS isrow, IS iscol, IS *isrow_d, IS *iscol_d, IS *iscol_o, PetscInt *garray[])
3146: {
3147:   Vec             x, cmap;
3148:   const PetscInt *is_idx;
3149:   PetscScalar    *xarray, *cmaparray;
3150:   PetscInt        ncols, isstart, *idx, m, rstart, *cmap1, count;
3151:   Mat_MPIAIJ     *a    = (Mat_MPIAIJ *)mat->data;
3152:   Mat             B    = a->B;
3153:   Vec             lvec = a->lvec, lcmap;
3154:   PetscInt        i, cstart, cend, Bn = B->cmap->N;
3155:   MPI_Comm        comm;
3156:   VecScatter      Mvctx = a->Mvctx;

3158:   PetscFunctionBegin;
3159:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3160:   PetscCall(ISGetLocalSize(iscol, &ncols));

3162:   /* (1) iscol is a sub-column vector of mat, pad it with '-1.' to form a full vector x */
3163:   PetscCall(MatCreateVecs(mat, &x, NULL));
3164:   PetscCall(VecSet(x, -1.0));
3165:   PetscCall(VecDuplicate(x, &cmap));
3166:   PetscCall(VecSet(cmap, -1.0));

3168:   /* Get start indices */
3169:   PetscCallMPI(MPI_Scan(&ncols, &isstart, 1, MPIU_INT, MPI_SUM, comm));
3170:   isstart -= ncols;
3171:   PetscCall(MatGetOwnershipRangeColumn(mat, &cstart, &cend));

3173:   PetscCall(ISGetIndices(iscol, &is_idx));
3174:   PetscCall(VecGetArray(x, &xarray));
3175:   PetscCall(VecGetArray(cmap, &cmaparray));
3176:   PetscCall(PetscMalloc1(ncols, &idx));
3177:   for (i = 0; i < ncols; i++) {
3178:     xarray[is_idx[i] - cstart]    = (PetscScalar)is_idx[i];
3179:     cmaparray[is_idx[i] - cstart] = i + isstart;        /* global index of iscol[i] */
3180:     idx[i]                        = is_idx[i] - cstart; /* local index of iscol[i]  */
3181:   }
3182:   PetscCall(VecRestoreArray(x, &xarray));
3183:   PetscCall(VecRestoreArray(cmap, &cmaparray));
3184:   PetscCall(ISRestoreIndices(iscol, &is_idx));

3186:   /* Get iscol_d */
3187:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, iscol_d));
3188:   PetscCall(ISGetBlockSize(iscol, &i));
3189:   PetscCall(ISSetBlockSize(*iscol_d, i));

3191:   /* Get isrow_d */
3192:   PetscCall(ISGetLocalSize(isrow, &m));
3193:   rstart = mat->rmap->rstart;
3194:   PetscCall(PetscMalloc1(m, &idx));
3195:   PetscCall(ISGetIndices(isrow, &is_idx));
3196:   for (i = 0; i < m; i++) idx[i] = is_idx[i] - rstart;
3197:   PetscCall(ISRestoreIndices(isrow, &is_idx));

3199:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, m, idx, PETSC_OWN_POINTER, isrow_d));
3200:   PetscCall(ISGetBlockSize(isrow, &i));
3201:   PetscCall(ISSetBlockSize(*isrow_d, i));

3203:   /* (2) Scatter x and cmap using aij->Mvctx to get their off-process portions (see MatMult_MPIAIJ) */
3204:   PetscCall(VecScatterBegin(Mvctx, x, lvec, INSERT_VALUES, SCATTER_FORWARD));
3205:   PetscCall(VecScatterEnd(Mvctx, x, lvec, INSERT_VALUES, SCATTER_FORWARD));

3207:   PetscCall(VecDuplicate(lvec, &lcmap));

3209:   PetscCall(VecScatterBegin(Mvctx, cmap, lcmap, INSERT_VALUES, SCATTER_FORWARD));
3210:   PetscCall(VecScatterEnd(Mvctx, cmap, lcmap, INSERT_VALUES, SCATTER_FORWARD));

3212:   /* (3) create sequential iscol_o (a subset of iscol) and isgarray */
3213:   /* off-process column indices */
3214:   count = 0;
3215:   PetscCall(PetscMalloc1(Bn, &idx));
3216:   PetscCall(PetscMalloc1(Bn, &cmap1));

3218:   PetscCall(VecGetArray(lvec, &xarray));
3219:   PetscCall(VecGetArray(lcmap, &cmaparray));
3220:   for (i = 0; i < Bn; i++) {
3221:     if (PetscRealPart(xarray[i]) > -1.0) {
3222:       idx[count]   = i;                                     /* local column index in off-diagonal part B */
3223:       cmap1[count] = (PetscInt)PetscRealPart(cmaparray[i]); /* column index in submat */
3224:       count++;
3225:     }
3226:   }
3227:   PetscCall(VecRestoreArray(lvec, &xarray));
3228:   PetscCall(VecRestoreArray(lcmap, &cmaparray));

3230:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count, idx, PETSC_COPY_VALUES, iscol_o));
3231:   /* cannot ensure iscol_o has same blocksize as iscol! */

3233:   PetscCall(PetscFree(idx));
3234:   *garray = cmap1;

3236:   PetscCall(VecDestroy(&x));
3237:   PetscCall(VecDestroy(&cmap));
3238:   PetscCall(VecDestroy(&lcmap));
3239:   PetscFunctionReturn(PETSC_SUCCESS);
3240: }

3242: /* isrow and iscol have same processor distribution as mat, output *submat is a submatrix of local mat */
3243: PetscErrorCode MatCreateSubMatrix_MPIAIJ_SameRowColDist(Mat mat, IS isrow, IS iscol, MatReuse call, Mat *submat)
3244: {
3245:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)mat->data, *asub;
3246:   Mat         M = NULL;
3247:   MPI_Comm    comm;
3248:   IS          iscol_d, isrow_d, iscol_o;
3249:   Mat         Asub = NULL, Bsub = NULL;
3250:   PetscInt    n, count, M_size, N_size;

3252:   PetscFunctionBegin;
3253:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));

3255:   if (call == MAT_REUSE_MATRIX) {
3256:     /* Retrieve isrow_d, iscol_d and iscol_o from submat */
3257:     PetscCall(PetscObjectQuery((PetscObject)*submat, "isrow_d", (PetscObject *)&isrow_d));
3258:     PetscCheck(isrow_d, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "isrow_d passed in was not used before, cannot reuse");

3260:     PetscCall(PetscObjectQuery((PetscObject)*submat, "iscol_d", (PetscObject *)&iscol_d));
3261:     PetscCheck(iscol_d, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "iscol_d passed in was not used before, cannot reuse");

3263:     PetscCall(PetscObjectQuery((PetscObject)*submat, "iscol_o", (PetscObject *)&iscol_o));
3264:     PetscCheck(iscol_o, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "iscol_o passed in was not used before, cannot reuse");

3266:     /* Update diagonal and off-diagonal portions of submat */
3267:     asub = (Mat_MPIAIJ *)(*submat)->data;
3268:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->A, isrow_d, iscol_d, PETSC_DECIDE, MAT_REUSE_MATRIX, &asub->A));
3269:     PetscCall(ISGetLocalSize(iscol_o, &n));
3270:     if (n) PetscCall(MatCreateSubMatrix_SeqAIJ(a->B, isrow_d, iscol_o, PETSC_DECIDE, MAT_REUSE_MATRIX, &asub->B));
3271:     PetscCall(MatAssemblyBegin(*submat, MAT_FINAL_ASSEMBLY));
3272:     PetscCall(MatAssemblyEnd(*submat, MAT_FINAL_ASSEMBLY));

3274:   } else { /* call == MAT_INITIAL_MATRIX) */
3275:     PetscInt *garray, *garray_compact;
3276:     PetscInt  BsubN;

3278:     /* Create isrow_d, iscol_d, iscol_o and isgarray (replace isgarray with array?) */
3279:     PetscCall(ISGetSeqIS_SameColDist_Private(mat, isrow, iscol, &isrow_d, &iscol_d, &iscol_o, &garray));

3281:     /* Create local submatrices Asub and Bsub */
3282:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->A, isrow_d, iscol_d, PETSC_DECIDE, MAT_INITIAL_MATRIX, &Asub));
3283:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->B, isrow_d, iscol_o, PETSC_DECIDE, MAT_INITIAL_MATRIX, &Bsub));

3285:     // Compact garray so its not of size Bn
3286:     PetscCall(ISGetSize(iscol_o, &count));
3287:     PetscCall(PetscMalloc1(count, &garray_compact));
3288:     PetscCall(PetscArraycpy(garray_compact, garray, count));

3290:     /* Create submatrix M */
3291:     PetscCall(ISGetSize(isrow, &M_size));
3292:     PetscCall(ISGetSize(iscol, &N_size));
3293:     PetscCall(MatCreateMPIAIJWithSeqAIJ(comm, M_size, N_size, Asub, Bsub, garray_compact, &M));

3295:     /* If Bsub has empty columns, compress iscol_o such that it will retrieve condensed Bsub from a->B during reuse */
3296:     asub = (Mat_MPIAIJ *)M->data;

3298:     PetscCall(ISGetLocalSize(iscol_o, &BsubN));
3299:     n = asub->B->cmap->N;
3300:     if (BsubN > n) {
3301:       /* This case can be tested using ~petsc/src/tao/bound/tutorials/runplate2_3 */
3302:       const PetscInt *idx;
3303:       PetscInt        i, j, *idx_new, *subgarray = asub->garray;
3304:       PetscCall(PetscInfo(M, "submatrix Bn %" PetscInt_FMT " != BsubN %" PetscInt_FMT ", update iscol_o\n", n, BsubN));

3306:       PetscCall(PetscMalloc1(n, &idx_new));
3307:       j = 0;
3308:       PetscCall(ISGetIndices(iscol_o, &idx));
3309:       for (i = 0; i < n; i++) {
3310:         if (j >= BsubN) break;
3311:         while (subgarray[i] > garray[j]) j++;

3313:         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]);
3314:         idx_new[i] = idx[j++];
3315:       }
3316:       PetscCall(ISRestoreIndices(iscol_o, &idx));

3318:       PetscCall(ISDestroy(&iscol_o));
3319:       PetscCall(ISCreateGeneral(PETSC_COMM_SELF, n, idx_new, PETSC_OWN_POINTER, &iscol_o));

3321:     } 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);

3323:     PetscCall(PetscFree(garray));
3324:     *submat = M;

3326:     /* Save isrow_d, iscol_d and iscol_o used in processor for next request */
3327:     PetscCall(PetscObjectCompose((PetscObject)M, "isrow_d", (PetscObject)isrow_d));
3328:     PetscCall(ISDestroy(&isrow_d));

3330:     PetscCall(PetscObjectCompose((PetscObject)M, "iscol_d", (PetscObject)iscol_d));
3331:     PetscCall(ISDestroy(&iscol_d));

3333:     PetscCall(PetscObjectCompose((PetscObject)M, "iscol_o", (PetscObject)iscol_o));
3334:     PetscCall(ISDestroy(&iscol_o));
3335:   }
3336:   PetscFunctionReturn(PETSC_SUCCESS);
3337: }

3339: PetscErrorCode MatCreateSubMatrix_MPIAIJ(Mat mat, IS isrow, IS iscol, MatReuse call, Mat *newmat)
3340: {
3341:   IS        iscol_local = NULL, isrow_d;
3342:   PetscInt  csize;
3343:   PetscInt  n, i, j, start, end;
3344:   PetscBool sameRowDist = PETSC_FALSE, sameDist[2], tsameDist[2];
3345:   MPI_Comm  comm;

3347:   PetscFunctionBegin;
3348:   /* If isrow has same processor distribution as mat,
3349:      call MatCreateSubMatrix_MPIAIJ_SameRowDist() to avoid using a hash table with global size of iscol */
3350:   if (call == MAT_REUSE_MATRIX) {
3351:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "isrow_d", (PetscObject *)&isrow_d));
3352:     if (isrow_d) {
3353:       sameRowDist  = PETSC_TRUE;
3354:       tsameDist[1] = PETSC_TRUE; /* sameColDist */
3355:     } else {
3356:       PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_local));
3357:       if (iscol_local) {
3358:         sameRowDist  = PETSC_TRUE;
3359:         tsameDist[1] = PETSC_FALSE; /* !sameColDist */
3360:       }
3361:     }
3362:   } else {
3363:     /* Check if isrow has same processor distribution as mat */
3364:     sameDist[0] = PETSC_FALSE;
3365:     PetscCall(ISGetLocalSize(isrow, &n));
3366:     if (!n) {
3367:       sameDist[0] = PETSC_TRUE;
3368:     } else {
3369:       PetscCall(ISGetMinMax(isrow, &i, &j));
3370:       PetscCall(MatGetOwnershipRange(mat, &start, &end));
3371:       if (i >= start && j < end) sameDist[0] = PETSC_TRUE;
3372:     }

3374:     /* Check if iscol has same processor distribution as mat */
3375:     sameDist[1] = PETSC_FALSE;
3376:     PetscCall(ISGetLocalSize(iscol, &n));
3377:     if (!n) {
3378:       sameDist[1] = PETSC_TRUE;
3379:     } else {
3380:       PetscCall(ISGetMinMax(iscol, &i, &j));
3381:       PetscCall(MatGetOwnershipRangeColumn(mat, &start, &end));
3382:       if (i >= start && j < end) sameDist[1] = PETSC_TRUE;
3383:     }

3385:     PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3386:     PetscCallMPI(MPIU_Allreduce(&sameDist, &tsameDist, 2, MPI_C_BOOL, MPI_LAND, comm));
3387:     sameRowDist = tsameDist[0];
3388:   }

3390:   if (sameRowDist) {
3391:     if (tsameDist[1]) { /* sameRowDist & sameColDist */
3392:       /* isrow and iscol have same processor distribution as mat */
3393:       PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowColDist(mat, isrow, iscol, call, newmat));
3394:       PetscFunctionReturn(PETSC_SUCCESS);
3395:     } else { /* sameRowDist */
3396:       /* isrow has same processor distribution as mat */
3397:       if (call == MAT_INITIAL_MATRIX) {
3398:         PetscBool sorted;
3399:         PetscCall(ISGetSeqIS_Private(mat, iscol, &iscol_local));
3400:         PetscCall(ISGetLocalSize(iscol_local, &n)); /* local size of iscol_local = global columns of newmat */
3401:         PetscCall(ISGetSize(iscol, &i));
3402:         PetscCheck(n == i, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "n %" PetscInt_FMT " != size of iscol %" PetscInt_FMT, n, i);

3404:         PetscCall(ISSorted(iscol_local, &sorted));
3405:         if (sorted) {
3406:           /* MatCreateSubMatrix_MPIAIJ_SameRowDist() requires iscol_local be sorted; it can have duplicate indices */
3407:           PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowDist(mat, isrow, iscol, iscol_local, MAT_INITIAL_MATRIX, newmat));
3408:           PetscFunctionReturn(PETSC_SUCCESS);
3409:         }
3410:       } else { /* call == MAT_REUSE_MATRIX */
3411:         IS iscol_sub;
3412:         PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_sub));
3413:         if (iscol_sub) {
3414:           PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowDist(mat, isrow, iscol, NULL, call, newmat));
3415:           PetscFunctionReturn(PETSC_SUCCESS);
3416:         }
3417:       }
3418:     }
3419:   }

3421:   /* General case: iscol -> iscol_local which has global size of iscol */
3422:   if (call == MAT_REUSE_MATRIX) {
3423:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "ISAllGather", (PetscObject *)&iscol_local));
3424:     PetscCheck(iscol_local, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");
3425:   } else {
3426:     if (!iscol_local) PetscCall(ISGetSeqIS_Private(mat, iscol, &iscol_local));
3427:   }

3429:   PetscCall(ISGetLocalSize(iscol, &csize));
3430:   PetscCall(MatCreateSubMatrix_MPIAIJ_nonscalable(mat, isrow, iscol_local, csize, call, newmat));

3432:   if (call == MAT_INITIAL_MATRIX) {
3433:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "ISAllGather", (PetscObject)iscol_local));
3434:     PetscCall(ISDestroy(&iscol_local));
3435:   }
3436:   PetscFunctionReturn(PETSC_SUCCESS);
3437: }

3439: /*@C
3440:   MatCreateMPIAIJWithSeqAIJ - creates a `MATMPIAIJ` matrix using `MATSEQAIJ` matrices that contain the "diagonal"
3441:   and "off-diagonal" part of the matrix in CSR format.

3443:   Collective

3445:   Input Parameters:
3446: + comm   - MPI communicator
3447: . M      - the global row size
3448: . N      - the global column size
3449: . A      - "diagonal" portion of matrix
3450: . 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
3451: - 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.

3453:   Output Parameter:
3454: . mat - the matrix, with input `A` as its local diagonal matrix

3456:   Level: advanced

3458:   Notes:
3459:   See `MatCreateAIJ()` for the definition of "diagonal" and "off-diagonal" portion of the matrix.

3461:   `A` and `B` becomes part of output mat. The user cannot use `A` and `B` anymore.

3463:   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
3464:   `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
3465:   `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`
3466:   yourself, see algorithms in the private function `MatSetUpMultiply_MPIAIJ()`.

3468:   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.

3470: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateMPIAIJWithSplitArrays()`
3471: @*/
3472: PetscErrorCode MatCreateMPIAIJWithSeqAIJ(MPI_Comm comm, PetscInt M, PetscInt N, Mat A, Mat B, PetscInt *garray, Mat *mat)
3473: {
3474:   PetscInt    m, n;
3475:   MatType     mpi_mat_type;
3476:   Mat_MPIAIJ *mpiaij;
3477:   Mat         C;

3479:   PetscFunctionBegin;
3480:   PetscCall(MatCreate(comm, &C));
3481:   PetscCall(MatGetSize(A, &m, &n));
3482:   PetscCheck(m == B->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Am %" PetscInt_FMT " != Bm %" PetscInt_FMT, m, B->rmap->N);
3483:   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);

3485:   PetscCall(MatSetSizes(C, m, n, M, N));
3486:   /* Determine the type of MPI matrix that should be created from the type of matrix A, which holds the "diagonal" portion. */
3487:   PetscCall(MatGetMPIMatType_Private(A, &mpi_mat_type));
3488:   PetscCall(MatSetType(C, mpi_mat_type));
3489:   if (!garray) {
3490:     const PetscScalar *ba;

3492:     B->nonzerostate++;
3493:     PetscCall(MatSeqAIJGetArrayRead(B, &ba)); /* Since we will destroy B's device copy, we need to make sure the host copy is up to date */
3494:     PetscCall(MatSeqAIJRestoreArrayRead(B, &ba));
3495:   }

3497:   PetscCall(MatSetBlockSizes(C, A->rmap->bs, A->cmap->bs));
3498:   PetscCall(PetscLayoutSetUp(C->rmap));
3499:   PetscCall(PetscLayoutSetUp(C->cmap));

3501:   mpiaij              = (Mat_MPIAIJ *)C->data;
3502:   mpiaij->A           = A;
3503:   mpiaij->B           = B;
3504:   mpiaij->garray      = garray;
3505:   C->preallocated     = PETSC_TRUE;
3506:   C->nooffprocentries = PETSC_TRUE; /* See MatAssemblyBegin_MPIAIJ. In effect, making MatAssemblyBegin a nop */

3508:   PetscCall(MatSetOption(C, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
3509:   PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
3510:   /* MatAssemblyEnd is critical here. It sets mat->offloadmask according to A and B's, and
3511:    also gets mpiaij->B compacted (if garray is NULL), with its col ids and size reduced
3512:    */
3513:   PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
3514:   PetscCall(MatSetOption(C, MAT_NO_OFF_PROC_ENTRIES, PETSC_FALSE));
3515:   PetscCall(MatSetOption(C, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
3516:   *mat = C;
3517:   PetscFunctionReturn(PETSC_SUCCESS);
3518: }

3520: extern PetscErrorCode MatCreateSubMatrices_MPIAIJ_SingleIS_Local(Mat, PetscInt, const IS[], const IS[], MatReuse, PetscBool, Mat *);

3522: PetscErrorCode MatCreateSubMatrix_MPIAIJ_SameRowDist(Mat mat, IS isrow, IS iscol, IS iscol_local, MatReuse call, Mat *newmat)
3523: {
3524:   PetscInt        i, m, n, rstart, row, rend, nz, j, bs, cbs;
3525:   PetscInt       *ii, *jj, nlocal, *dlens, *olens, dlen, olen, jend, mglobal;
3526:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)mat->data;
3527:   Mat             M, Msub, B = a->B;
3528:   MatScalar      *aa;
3529:   Mat_SeqAIJ     *aij;
3530:   PetscInt       *garray = a->garray, *colsub, Ncols;
3531:   PetscInt        count, Bn = B->cmap->N, cstart = mat->cmap->rstart, cend = mat->cmap->rend;
3532:   IS              iscol_sub, iscmap;
3533:   const PetscInt *is_idx, *cmap;
3534:   PetscBool       allcolumns = PETSC_FALSE;
3535:   MPI_Comm        comm;

3537:   PetscFunctionBegin;
3538:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3539:   if (call == MAT_REUSE_MATRIX) {
3540:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_sub));
3541:     PetscCheck(iscol_sub, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "SubIScol passed in was not used before, cannot reuse");
3542:     PetscCall(ISGetLocalSize(iscol_sub, &count));

3544:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "Subcmap", (PetscObject *)&iscmap));
3545:     PetscCheck(iscmap, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Subcmap passed in was not used before, cannot reuse");

3547:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubMatrix", (PetscObject *)&Msub));
3548:     PetscCheck(Msub, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");

3550:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol_sub, MAT_REUSE_MATRIX, PETSC_FALSE, &Msub));

3552:   } else { /* call == MAT_INITIAL_MATRIX) */
3553:     PetscBool flg;

3555:     PetscCall(ISGetLocalSize(iscol, &n));
3556:     PetscCall(ISGetSize(iscol, &Ncols));

3558:     /* (1) iscol -> nonscalable iscol_local */
3559:     /* Check for special case: each processor gets entire matrix columns */
3560:     PetscCall(ISIdentity(iscol_local, &flg));
3561:     if (flg && n == mat->cmap->N) allcolumns = PETSC_TRUE;
3562:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &allcolumns, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));
3563:     if (allcolumns) {
3564:       iscol_sub = iscol_local;
3565:       PetscCall(PetscObjectReference((PetscObject)iscol_local));
3566:       PetscCall(ISCreateStride(PETSC_COMM_SELF, n, 0, 1, &iscmap));

3568:     } else {
3569:       /* (2) iscol_local -> iscol_sub and iscmap. Implementation below requires iscol_local be sorted, it can have duplicate indices */
3570:       PetscInt *idx, *cmap1, k;
3571:       PetscCall(PetscMalloc1(Ncols, &idx));
3572:       PetscCall(PetscMalloc1(Ncols, &cmap1));
3573:       PetscCall(ISGetIndices(iscol_local, &is_idx));
3574:       count = 0;
3575:       k     = 0;
3576:       for (i = 0; i < Ncols; i++) {
3577:         j = is_idx[i];
3578:         if (j >= cstart && j < cend) {
3579:           /* diagonal part of mat */
3580:           idx[count]     = j;
3581:           cmap1[count++] = i; /* column index in submat */
3582:         } else if (Bn) {
3583:           /* off-diagonal part of mat */
3584:           if (j == garray[k]) {
3585:             idx[count]     = j;
3586:             cmap1[count++] = i; /* column index in submat */
3587:           } else if (j > garray[k]) {
3588:             while (j > garray[k] && k < Bn - 1) k++;
3589:             if (j == garray[k]) {
3590:               idx[count]     = j;
3591:               cmap1[count++] = i; /* column index in submat */
3592:             }
3593:           }
3594:         }
3595:       }
3596:       PetscCall(ISRestoreIndices(iscol_local, &is_idx));

3598:       PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count, idx, PETSC_OWN_POINTER, &iscol_sub));
3599:       PetscCall(ISGetBlockSize(iscol, &cbs));
3600:       PetscCall(ISSetBlockSize(iscol_sub, cbs));

3602:       PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)iscol_local), count, cmap1, PETSC_OWN_POINTER, &iscmap));
3603:     }

3605:     /* (3) Create sequential Msub */
3606:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol_sub, MAT_INITIAL_MATRIX, allcolumns, &Msub));
3607:   }

3609:   PetscCall(ISGetLocalSize(iscol_sub, &count));
3610:   aij = (Mat_SeqAIJ *)Msub->data;
3611:   ii  = aij->i;
3612:   PetscCall(ISGetIndices(iscmap, &cmap));

3614:   /*
3615:       m - number of local rows
3616:       Ncols - number of columns (same on all processors)
3617:       rstart - first row in new global matrix generated
3618:   */
3619:   PetscCall(MatGetSize(Msub, &m, NULL));

3621:   if (call == MAT_INITIAL_MATRIX) {
3622:     /* (4) Create parallel newmat */
3623:     PetscMPIInt rank, size;
3624:     PetscInt    csize;

3626:     PetscCallMPI(MPI_Comm_size(comm, &size));
3627:     PetscCallMPI(MPI_Comm_rank(comm, &rank));

3629:     /*
3630:         Determine the number of non-zeros in the diagonal and off-diagonal
3631:         portions of the matrix in order to do correct preallocation
3632:     */

3634:     /* first get start and end of "diagonal" columns */
3635:     PetscCall(ISGetLocalSize(iscol, &csize));
3636:     if (csize == PETSC_DECIDE) {
3637:       PetscCall(ISGetSize(isrow, &mglobal));
3638:       if (mglobal == Ncols) { /* square matrix */
3639:         nlocal = m;
3640:       } else {
3641:         nlocal = Ncols / size + ((Ncols % size) > rank);
3642:       }
3643:     } else {
3644:       nlocal = csize;
3645:     }
3646:     PetscCallMPI(MPI_Scan(&nlocal, &rend, 1, MPIU_INT, MPI_SUM, comm));
3647:     rstart = rend - nlocal;
3648:     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);

3650:     /* next, compute all the lengths */
3651:     jj = aij->j;
3652:     PetscCall(PetscMalloc1(2 * m + 1, &dlens));
3653:     olens = dlens + m;
3654:     for (i = 0; i < m; i++) {
3655:       jend = ii[i + 1] - ii[i];
3656:       olen = 0;
3657:       dlen = 0;
3658:       for (j = 0; j < jend; j++) {
3659:         if (cmap[*jj] < rstart || cmap[*jj] >= rend) olen++;
3660:         else dlen++;
3661:         jj++;
3662:       }
3663:       olens[i] = olen;
3664:       dlens[i] = dlen;
3665:     }

3667:     PetscCall(ISGetBlockSize(isrow, &bs));
3668:     PetscCall(ISGetBlockSize(iscol, &cbs));

3670:     PetscCall(MatCreate(comm, &M));
3671:     PetscCall(MatSetSizes(M, m, nlocal, PETSC_DECIDE, Ncols));
3672:     PetscCall(MatSetBlockSizes(M, bs, cbs));
3673:     PetscCall(MatSetType(M, ((PetscObject)mat)->type_name));
3674:     PetscCall(MatMPIAIJSetPreallocation(M, 0, dlens, 0, olens));
3675:     PetscCall(PetscFree(dlens));

3677:   } else { /* call == MAT_REUSE_MATRIX */
3678:     M = *newmat;
3679:     PetscCall(MatGetLocalSize(M, &i, NULL));
3680:     PetscCheck(i == m, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Previous matrix must be same size/layout as request");
3681:     PetscCall(MatZeroEntries(M));
3682:     /*
3683:          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3684:        rather than the slower MatSetValues().
3685:     */
3686:     M->was_assembled = PETSC_TRUE;
3687:     M->assembled     = PETSC_FALSE;
3688:   }

3690:   /* (5) Set values of Msub to *newmat */
3691:   PetscCall(PetscMalloc1(count, &colsub));
3692:   PetscCall(MatGetOwnershipRange(M, &rstart, NULL));

3694:   jj = aij->j;
3695:   PetscCall(MatSeqAIJGetArrayRead(Msub, (const PetscScalar **)&aa));
3696:   for (i = 0; i < m; i++) {
3697:     row = rstart + i;
3698:     nz  = ii[i + 1] - ii[i];
3699:     for (j = 0; j < nz; j++) colsub[j] = cmap[jj[j]];
3700:     PetscCall(MatSetValues_MPIAIJ(M, 1, &row, nz, colsub, aa, INSERT_VALUES));
3701:     jj += nz;
3702:     aa += nz;
3703:   }
3704:   PetscCall(MatSeqAIJRestoreArrayRead(Msub, (const PetscScalar **)&aa));
3705:   PetscCall(ISRestoreIndices(iscmap, &cmap));

3707:   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
3708:   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));

3710:   PetscCall(PetscFree(colsub));

3712:   /* save Msub, iscol_sub and iscmap used in processor for next request */
3713:   if (call == MAT_INITIAL_MATRIX) {
3714:     *newmat = M;
3715:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "SubMatrix", (PetscObject)Msub));
3716:     PetscCall(MatDestroy(&Msub));

3718:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "SubIScol", (PetscObject)iscol_sub));
3719:     PetscCall(ISDestroy(&iscol_sub));

3721:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "Subcmap", (PetscObject)iscmap));
3722:     PetscCall(ISDestroy(&iscmap));

3724:     if (iscol_local) {
3725:       PetscCall(PetscObjectCompose((PetscObject)*newmat, "ISAllGather", (PetscObject)iscol_local));
3726:       PetscCall(ISDestroy(&iscol_local));
3727:     }
3728:   }
3729:   PetscFunctionReturn(PETSC_SUCCESS);
3730: }

3732: /*
3733:     Not great since it makes two copies of the submatrix, first an SeqAIJ
3734:   in local and then by concatenating the local matrices the end result.
3735:   Writing it directly would be much like MatCreateSubMatrices_MPIAIJ()

3737:   This requires a sequential iscol with all indices.
3738: */
3739: PetscErrorCode MatCreateSubMatrix_MPIAIJ_nonscalable(Mat mat, IS isrow, IS iscol, PetscInt csize, MatReuse call, Mat *newmat)
3740: {
3741:   PetscMPIInt rank, size;
3742:   PetscInt    i, m, n, rstart, row, rend, nz, *cwork, j, bs, cbs;
3743:   PetscInt   *ii, *jj, nlocal, *dlens, *olens, dlen, olen, jend, mglobal;
3744:   Mat         M, Mreuse;
3745:   MatScalar  *aa, *vwork;
3746:   MPI_Comm    comm;
3747:   Mat_SeqAIJ *aij;
3748:   PetscBool   colflag, allcolumns = PETSC_FALSE;

3750:   PetscFunctionBegin;
3751:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3752:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
3753:   PetscCallMPI(MPI_Comm_size(comm, &size));

3755:   /* Check for special case: each processor gets entire matrix columns */
3756:   PetscCall(ISIdentity(iscol, &colflag));
3757:   PetscCall(ISGetLocalSize(iscol, &n));
3758:   if (colflag && n == mat->cmap->N) allcolumns = PETSC_TRUE;
3759:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &allcolumns, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));

3761:   if (call == MAT_REUSE_MATRIX) {
3762:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubMatrix", (PetscObject *)&Mreuse));
3763:     PetscCheck(Mreuse, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");
3764:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol, MAT_REUSE_MATRIX, allcolumns, &Mreuse));
3765:   } else {
3766:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol, MAT_INITIAL_MATRIX, allcolumns, &Mreuse));
3767:   }

3769:   /*
3770:       m - number of local rows
3771:       n - number of columns (same on all processors)
3772:       rstart - first row in new global matrix generated
3773:   */
3774:   PetscCall(MatGetSize(Mreuse, &m, &n));
3775:   PetscCall(MatGetBlockSizes(Mreuse, &bs, &cbs));
3776:   if (call == MAT_INITIAL_MATRIX) {
3777:     aij = (Mat_SeqAIJ *)Mreuse->data;
3778:     ii  = aij->i;
3779:     jj  = aij->j;

3781:     /*
3782:         Determine the number of non-zeros in the diagonal and off-diagonal
3783:         portions of the matrix in order to do correct preallocation
3784:     */

3786:     /* first get start and end of "diagonal" columns */
3787:     if (csize == PETSC_DECIDE) {
3788:       PetscCall(ISGetSize(isrow, &mglobal));
3789:       if (mglobal == n) { /* square matrix */
3790:         nlocal = m;
3791:       } else {
3792:         nlocal = n / size + ((n % size) > rank);
3793:       }
3794:     } else {
3795:       nlocal = csize;
3796:     }
3797:     PetscCallMPI(MPI_Scan(&nlocal, &rend, 1, MPIU_INT, MPI_SUM, comm));
3798:     rstart = rend - nlocal;
3799:     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);

3801:     /* next, compute all the lengths */
3802:     PetscCall(PetscMalloc1(2 * m + 1, &dlens));
3803:     olens = dlens + m;
3804:     for (i = 0; i < m; i++) {
3805:       jend = ii[i + 1] - ii[i];
3806:       olen = 0;
3807:       dlen = 0;
3808:       for (j = 0; j < jend; j++) {
3809:         if (*jj < rstart || *jj >= rend) olen++;
3810:         else dlen++;
3811:         jj++;
3812:       }
3813:       olens[i] = olen;
3814:       dlens[i] = dlen;
3815:     }
3816:     PetscCall(MatCreate(comm, &M));
3817:     PetscCall(MatSetSizes(M, m, nlocal, PETSC_DECIDE, n));
3818:     PetscCall(MatSetBlockSizes(M, bs, cbs));
3819:     PetscCall(MatSetType(M, ((PetscObject)mat)->type_name));
3820:     PetscCall(MatMPIAIJSetPreallocation(M, 0, dlens, 0, olens));
3821:     PetscCall(PetscFree(dlens));
3822:   } else {
3823:     PetscInt ml, nl;

3825:     M = *newmat;
3826:     PetscCall(MatGetLocalSize(M, &ml, &nl));
3827:     PetscCheck(ml == m, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Previous matrix must be same size/layout as request");
3828:     PetscCall(MatZeroEntries(M));
3829:     /*
3830:          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3831:        rather than the slower MatSetValues().
3832:     */
3833:     M->was_assembled = PETSC_TRUE;
3834:     M->assembled     = PETSC_FALSE;
3835:   }
3836:   PetscCall(MatGetOwnershipRange(M, &rstart, &rend));
3837:   aij = (Mat_SeqAIJ *)Mreuse->data;
3838:   ii  = aij->i;
3839:   jj  = aij->j;

3841:   /* trigger copy to CPU if needed */
3842:   PetscCall(MatSeqAIJGetArrayRead(Mreuse, (const PetscScalar **)&aa));
3843:   for (i = 0; i < m; i++) {
3844:     row   = rstart + i;
3845:     nz    = ii[i + 1] - ii[i];
3846:     cwork = jj;
3847:     jj    = PetscSafePointerPlusOffset(jj, nz);
3848:     vwork = aa;
3849:     aa    = PetscSafePointerPlusOffset(aa, nz);
3850:     PetscCall(MatSetValues_MPIAIJ(M, 1, &row, nz, cwork, vwork, INSERT_VALUES));
3851:   }
3852:   PetscCall(MatSeqAIJRestoreArrayRead(Mreuse, (const PetscScalar **)&aa));

3854:   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
3855:   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));
3856:   *newmat = M;

3858:   /* save submatrix used in processor for next request */
3859:   if (call == MAT_INITIAL_MATRIX) {
3860:     PetscCall(PetscObjectCompose((PetscObject)M, "SubMatrix", (PetscObject)Mreuse));
3861:     PetscCall(MatDestroy(&Mreuse));
3862:   }
3863:   PetscFunctionReturn(PETSC_SUCCESS);
3864: }

3866: static PetscErrorCode MatMPIAIJSetPreallocationCSR_MPIAIJ(Mat B, const PetscInt Ii[], const PetscInt J[], const PetscScalar v[])
3867: {
3868:   PetscInt        m, cstart, cend, j, nnz, i, d, *ld;
3869:   PetscInt       *d_nnz, *o_nnz, nnz_max = 0, rstart, ii, irstart;
3870:   const PetscInt *JJ;
3871:   PetscBool       nooffprocentries;
3872:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)B->data;

3874:   PetscFunctionBegin;
3875:   PetscCall(PetscLayoutSetUp(B->rmap));
3876:   PetscCall(PetscLayoutSetUp(B->cmap));
3877:   m       = B->rmap->n;
3878:   cstart  = B->cmap->rstart;
3879:   cend    = B->cmap->rend;
3880:   rstart  = B->rmap->rstart;
3881:   irstart = Ii[0];

3883:   PetscCall(PetscCalloc2(m, &d_nnz, m, &o_nnz));

3885:   if (PetscDefined(USE_DEBUG)) {
3886:     for (i = 0; i < m; i++) {
3887:       nnz = Ii[i + 1] - Ii[i];
3888:       JJ  = PetscSafePointerPlusOffset(J, Ii[i] - irstart);
3889:       PetscCheck(nnz >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Local row %" PetscInt_FMT " has a negative %" PetscInt_FMT " number of columns", i, nnz);
3890:       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]);
3891:       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);
3892:     }
3893:   }

3895:   for (i = 0; i < m; i++) {
3896:     nnz     = Ii[i + 1] - Ii[i];
3897:     JJ      = PetscSafePointerPlusOffset(J, Ii[i] - irstart);
3898:     nnz_max = PetscMax(nnz_max, nnz);
3899:     d       = 0;
3900:     for (j = 0; j < nnz; j++) {
3901:       if (cstart <= JJ[j] && JJ[j] < cend) d++;
3902:     }
3903:     d_nnz[i] = d;
3904:     o_nnz[i] = nnz - d;
3905:   }
3906:   PetscCall(MatMPIAIJSetPreallocation(B, 0, d_nnz, 0, o_nnz));
3907:   PetscCall(PetscFree2(d_nnz, o_nnz));

3909:   for (i = 0; i < m; i++) {
3910:     ii = i + rstart;
3911:     PetscCall(MatSetValues_MPIAIJ(B, 1, &ii, Ii[i + 1] - Ii[i], PetscSafePointerPlusOffset(J, Ii[i] - irstart), PetscSafePointerPlusOffset(v, Ii[i] - irstart), INSERT_VALUES));
3912:   }
3913:   nooffprocentries    = B->nooffprocentries;
3914:   B->nooffprocentries = PETSC_TRUE;
3915:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
3916:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
3917:   B->nooffprocentries = nooffprocentries;

3919:   /* count number of entries below block diagonal */
3920:   PetscCall(PetscFree(Aij->ld));
3921:   PetscCall(PetscCalloc1(m, &ld));
3922:   Aij->ld = ld;
3923:   for (i = 0; i < m; i++) {
3924:     nnz = Ii[i + 1] - Ii[i];
3925:     j   = 0;
3926:     while (j < nnz && J[j] < cstart) j++;
3927:     ld[i] = j;
3928:     if (J) J += nnz;
3929:   }

3931:   PetscCall(MatSetOption(B, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
3932:   PetscFunctionReturn(PETSC_SUCCESS);
3933: }

3935: /*@
3936:   MatMPIAIJSetPreallocationCSR - Allocates memory for a sparse parallel matrix in `MATAIJ` format
3937:   (the default parallel PETSc format).

3939:   Collective

3941:   Input Parameters:
3942: + B - the matrix
3943: . i - the indices into `j` for the start of each local row (indices start with zero)
3944: . j - the column indices for each local row (indices start with zero)
3945: - v - optional values in the matrix

3947:   Level: developer

3949:   Notes:
3950:   The `i`, `j`, and `v` arrays ARE copied by this routine into the internal format used by PETSc;
3951:   thus you CANNOT change the matrix entries by changing the values of `v` after you have
3952:   called this routine. Use `MatCreateMPIAIJWithSplitArrays()` to avoid needing to copy the arrays.

3954:   The `i` and `j` indices are 0 based, and `i` indices are indices corresponding to the local `j` array.

3956:   A convenience routine for this functionality is `MatCreateMPIAIJWithArrays()`.

3958:   You can update the matrix with new numerical values using `MatUpdateMPIAIJWithArrays()` after this call if the column indices in `j` are sorted.

3960:   If you do **not** use `MatUpdateMPIAIJWithArrays()`, the column indices in `j` do not need to be sorted. If you will use
3961:   `MatUpdateMPIAIJWithArrays()`, the column indices **must** be sorted.

3963:   The format which is used for the sparse matrix input, is equivalent to a
3964:   row-major ordering.. i.e for the following matrix, the input data expected is
3965:   as shown
3966: .vb
3967:         1 0 0
3968:         2 0 3     P0
3969:        -------
3970:         4 5 6     P1

3972:      Process0 [P0] rows_owned=[0,1]
3973:         i =  {0,1,3}  [size = nrow+1  = 2+1]
3974:         j =  {0,0,2}  [size = 3]
3975:         v =  {1,2,3}  [size = 3]

3977:      Process1 [P1] rows_owned=[2]
3978:         i =  {0,3}    [size = nrow+1  = 1+1]
3979:         j =  {0,1,2}  [size = 3]
3980:         v =  {4,5,6}  [size = 3]
3981: .ve

3983: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatCreateAIJ()`,
3984:           `MatCreateSeqAIJWithArrays()`, `MatCreateMPIAIJWithSplitArrays()`, `MatCreateMPIAIJWithArrays()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
3985: @*/
3986: PetscErrorCode MatMPIAIJSetPreallocationCSR(Mat B, const PetscInt i[], const PetscInt j[], const PetscScalar v[])
3987: {
3988:   PetscFunctionBegin;
3989:   PetscTryMethod(B, "MatMPIAIJSetPreallocationCSR_C", (Mat, const PetscInt[], const PetscInt[], const PetscScalar[]), (B, i, j, v));
3990:   PetscFunctionReturn(PETSC_SUCCESS);
3991: }

3993: /*@
3994:   MatMPIAIJSetPreallocation - Preallocates memory for a sparse parallel matrix in `MATMPIAIJ` format
3995:   (the default parallel PETSc format).  For good matrix assembly performance
3996:   the user should preallocate the matrix storage by setting the parameters
3997:   `d_nz` (or `d_nnz`) and `o_nz` (or `o_nnz`).

3999:   Collective

4001:   Input Parameters:
4002: + B     - the matrix
4003: . d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4004:            (same value is used for all local rows)
4005: . d_nnz - array containing the number of nonzeros in the various rows of the
4006:            DIAGONAL portion of the local submatrix (possibly different for each row)
4007:            or `NULL` (`PETSC_NULL_INTEGER` in Fortran), if `d_nz` is used to specify the nonzero structure.
4008:            The size of this array is equal to the number of local rows, i.e 'm'.
4009:            For matrices that will be factored, you must leave room for (and set)
4010:            the diagonal entry even if it is zero.
4011: . o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4012:            submatrix (same value is used for all local rows).
4013: - o_nnz - array containing the number of nonzeros in the various rows of the
4014:            OFF-DIAGONAL portion of the local submatrix (possibly different for
4015:            each row) or `NULL` (`PETSC_NULL_INTEGER` in Fortran), if `o_nz` is used to specify the nonzero
4016:            structure. The size of this array is equal to the number
4017:            of local rows, i.e 'm'.

4019:   Example Usage:
4020:   Consider the following 8x8 matrix with 34 non-zero values, that is
4021:   assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4022:   proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4023:   as follows

4025: .vb
4026:             1  2  0  |  0  3  0  |  0  4
4027:     Proc0   0  5  6  |  7  0  0  |  8  0
4028:             9  0 10  | 11  0  0  | 12  0
4029:     -------------------------------------
4030:            13  0 14  | 15 16 17  |  0  0
4031:     Proc1   0 18  0  | 19 20 21  |  0  0
4032:             0  0  0  | 22 23  0  | 24  0
4033:     -------------------------------------
4034:     Proc2  25 26 27  |  0  0 28  | 29  0
4035:            30  0  0  | 31 32 33  |  0 34
4036: .ve

4038:   This can be represented as a collection of submatrices as
4039: .vb
4040:       A B C
4041:       D E F
4042:       G H I
4043: .ve

4045:   Where the submatrices A,B,C are owned by proc0, D,E,F are
4046:   owned by proc1, G,H,I are owned by proc2.

4048:   The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4049:   The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4050:   The 'M','N' parameters are 8,8, and have the same values on all procs.

4052:   The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4053:   submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4054:   corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4055:   Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4056:   part as `MATSEQAIJ` matrices. For example, proc1 will store [E] as a `MATSEQAIJ`
4057:   matrix, and [DF] as another `MATSEQAIJ` matrix.

4059:   When `d_nz`, `o_nz` parameters are specified, `d_nz` storage elements are
4060:   allocated for every row of the local DIAGONAL submatrix, and `o_nz`
4061:   storage locations are allocated for every row of the OFF-DIAGONAL submatrix.
4062:   One way to choose `d_nz` and `o_nz` is to use the maximum number of nonzeros over
4063:   the local rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4064:   In this case, the values of `d_nz`, `o_nz` are
4065: .vb
4066:      proc0  dnz = 2, o_nz = 2
4067:      proc1  dnz = 3, o_nz = 2
4068:      proc2  dnz = 1, o_nz = 4
4069: .ve
4070:   We are allocating `m`*(`d_nz`+`o_nz`) storage locations for every proc. This
4071:   translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4072:   for proc3. i.e we are using 12+15+10=37 storage locations to store
4073:   34 values.

4075:   When `d_nnz`, `o_nnz` parameters are specified, the storage is specified
4076:   for every row, corresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4077:   In the above case the values for `d_nnz`, `o_nnz` are
4078: .vb
4079:      proc0 d_nnz = [2,2,2] and o_nnz = [2,2,2]
4080:      proc1 d_nnz = [3,3,2] and o_nnz = [2,1,1]
4081:      proc2 d_nnz = [1,1]   and o_nnz = [4,4]
4082: .ve
4083:   Here the space allocated is sum of all the above values i.e 34, and
4084:   hence pre-allocation is perfect.

4086:   Level: intermediate

4088:   Notes:
4089:   If the *_nnz parameter is given then the *_nz parameter is ignored

4091:   The `MATAIJ` format, also called compressed row storage (CSR), is compatible with standard Fortran
4092:   storage.  The stored row and column indices begin with zero.
4093:   See [Sparse Matrices](sec_matsparse) for details.

4095:   The parallel matrix is partitioned such that the first m0 rows belong to
4096:   process 0, the next m1 rows belong to process 1, the next m2 rows belong
4097:   to process 2 etc.. where m0,m1,m2... are the input parameter 'm'.

4099:   The DIAGONAL portion of the local submatrix of a processor can be defined
4100:   as the submatrix which is obtained by extraction the part corresponding to
4101:   the rows r1-r2 and columns c1-c2 of the global matrix, where r1 is the
4102:   first row that belongs to the processor, r2 is the last row belonging to
4103:   the this processor, and c1-c2 is range of indices of the local part of a
4104:   vector suitable for applying the matrix to.  This is an mxn matrix.  In the
4105:   common case of a square matrix, the row and column ranges are the same and
4106:   the DIAGONAL part is also square. The remaining portion of the local
4107:   submatrix (mxN) constitute the OFF-DIAGONAL portion.

4109:   If `o_nnz` and `d_nnz` are specified, then `o_nz` and `d_nz` are ignored.

4111:   You can call `MatGetInfo()` to get information on how effective the preallocation was;
4112:   for example the fields mallocs,nz_allocated,nz_used,nz_unneeded;
4113:   You can also run with the option `-info` and look for messages with the string
4114:   malloc in them to see if additional memory allocation was needed.

4116: .seealso: [](ch_matrices), `Mat`, [Sparse Matrices](sec_matsparse), `MATMPIAIJ`, `MATAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatCreateAIJ()`, `MatMPIAIJSetPreallocationCSR()`,
4117:           `MatGetInfo()`, `PetscSplitOwnership()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4118: @*/
4119: PetscErrorCode MatMPIAIJSetPreallocation(Mat B, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[])
4120: {
4121:   PetscFunctionBegin;
4124:   PetscTryMethod(B, "MatMPIAIJSetPreallocation_C", (Mat, PetscInt, const PetscInt[], PetscInt, const PetscInt[]), (B, d_nz, d_nnz, o_nz, o_nnz));
4125:   PetscFunctionReturn(PETSC_SUCCESS);
4126: }

4128: /*@
4129:   MatCreateMPIAIJWithArrays - creates a `MATMPIAIJ` matrix using arrays that contain in standard
4130:   CSR format for the local rows.

4132:   Collective

4134:   Input Parameters:
4135: + comm - MPI communicator
4136: . m    - number of local rows (Cannot be `PETSC_DECIDE`)
4137: . n    - This value should be the same as the local size used in creating the
4138:          x vector for the matrix-vector product $ y = Ax$. (or `PETSC_DECIDE` to have
4139:          calculated if `N` is given) For square matrices n is almost always `m`.
4140: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if `m` is given)
4141: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if `n` is given)
4142: . 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
4143: . j    - global column indices
4144: - a    - optional matrix values

4146:   Output Parameter:
4147: . mat - the matrix

4149:   Level: intermediate

4151:   Notes:
4152:   The `i`, `j`, and `a` arrays ARE copied by this routine into the internal format used by PETSc;
4153:   thus you CANNOT change the matrix entries by changing the values of `a[]` after you have
4154:   called this routine. Use `MatCreateMPIAIJWithSplitArrays()` to avoid needing to copy the arrays.

4156:   The `i` and `j` indices are 0 based, and `i` indices are indices corresponding to the local `j` array.

4158:   Once you have created the matrix you can update it with new numerical values using `MatUpdateMPIAIJWithArray()`

4160:   If you do **not** use `MatUpdateMPIAIJWithArray()`, the column indices in `j` do not need to be sorted. If you will use
4161:   `MatUpdateMPIAIJWithArrays()`, the column indices **must** be sorted.

4163:   The format which is used for the sparse matrix input, is equivalent to a
4164:   row-major ordering, i.e., for the following matrix, the input data expected is
4165:   as shown
4166: .vb
4167:         1 0 0
4168:         2 0 3     P0
4169:        -------
4170:         4 5 6     P1

4172:      Process0 [P0] rows_owned=[0,1]
4173:         i =  {0,1,3}  [size = nrow+1  = 2+1]
4174:         j =  {0,0,2}  [size = 3]
4175:         v =  {1,2,3}  [size = 3]

4177:      Process1 [P1] rows_owned=[2]
4178:         i =  {0,3}    [size = nrow+1  = 1+1]
4179:         j =  {0,1,2}  [size = 3]
4180:         v =  {4,5,6}  [size = 3]
4181: .ve

4183: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4184:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArray()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4185: @*/
4186: PetscErrorCode MatCreateMPIAIJWithArrays(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt M, PetscInt N, const PetscInt i[], const PetscInt j[], const PetscScalar a[], Mat *mat)
4187: {
4188:   PetscFunctionBegin;
4189:   PetscCheck(!i || !i[0], PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
4190:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
4191:   PetscCall(MatCreate(comm, mat));
4192:   PetscCall(MatSetSizes(*mat, m, n, M, N));
4193:   /* PetscCall(MatSetBlockSizes(M,bs,cbs)); */
4194:   PetscCall(MatSetType(*mat, MATMPIAIJ));
4195:   PetscCall(MatMPIAIJSetPreallocationCSR(*mat, i, j, a));
4196:   PetscFunctionReturn(PETSC_SUCCESS);
4197: }

4199: /*@
4200:   MatUpdateMPIAIJWithArrays - updates a `MATMPIAIJ` matrix using arrays that contain in standard
4201:   CSR format for the local rows. Only the numerical values are updated the other arrays must be identical to what was passed
4202:   from `MatCreateMPIAIJWithArrays()`

4204:   Deprecated: Use `MatUpdateMPIAIJWithArray()`

4206:   Collective

4208:   Input Parameters:
4209: + mat - the matrix
4210: . m   - number of local rows (Cannot be `PETSC_DECIDE`)
4211: . n   - This value should be the same as the local size used in creating the
4212:        x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4213:        calculated if N is given) For square matrices n is almost always m.
4214: . M   - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4215: . N   - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4216: . Ii  - row indices; that is Ii[0] = 0, Ii[row] = Ii[row-1] + number of elements in that row of the matrix
4217: . J   - column indices
4218: - v   - matrix values

4220:   Level: deprecated

4222: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4223:           `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArray()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4224: @*/
4225: PetscErrorCode MatUpdateMPIAIJWithArrays(Mat mat, PetscInt m, PetscInt n, PetscInt M, PetscInt N, const PetscInt Ii[], const PetscInt J[], const PetscScalar v[])
4226: {
4227:   PetscInt        nnz, i;
4228:   PetscBool       nooffprocentries;
4229:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)mat->data;
4230:   Mat_SeqAIJ     *Ad  = (Mat_SeqAIJ *)Aij->A->data;
4231:   PetscScalar    *ad, *ao;
4232:   PetscInt        ldi, Iii, md;
4233:   const PetscInt *Adi = Ad->i;
4234:   PetscInt       *ld  = Aij->ld;

4236:   PetscFunctionBegin;
4237:   PetscCheck(Ii[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
4238:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
4239:   PetscCheck(m == mat->rmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Local number of rows cannot change from call to MatUpdateMPIAIJWithArrays()");
4240:   PetscCheck(n == mat->cmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Local number of columns cannot change from call to MatUpdateMPIAIJWithArrays()");

4242:   PetscCall(MatSeqAIJGetArrayWrite(Aij->A, &ad));
4243:   PetscCall(MatSeqAIJGetArrayWrite(Aij->B, &ao));

4245:   for (i = 0; i < m; i++) {
4246:     if (PetscDefined(USE_DEBUG)) {
4247:       for (PetscInt j = Ii[i] + 1; j < Ii[i + 1]; ++j) {
4248:         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);
4249:         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);
4250:       }
4251:     }
4252:     nnz = Ii[i + 1] - Ii[i];
4253:     Iii = Ii[i];
4254:     ldi = ld[i];
4255:     md  = Adi[i + 1] - Adi[i];
4256:     PetscCall(PetscArraycpy(ao, v + Iii, ldi));
4257:     PetscCall(PetscArraycpy(ad, v + Iii + ldi, md));
4258:     PetscCall(PetscArraycpy(ao + ldi, v + Iii + ldi + md, nnz - ldi - md));
4259:     ad += md;
4260:     ao += nnz - md;
4261:   }
4262:   nooffprocentries      = mat->nooffprocentries;
4263:   mat->nooffprocentries = PETSC_TRUE;
4264:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->A, &ad));
4265:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->B, &ao));
4266:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->A));
4267:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->B));
4268:   PetscCall(PetscObjectStateIncrease((PetscObject)mat));
4269:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
4270:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
4271:   mat->nooffprocentries = nooffprocentries;
4272:   PetscFunctionReturn(PETSC_SUCCESS);
4273: }

4275: /*@
4276:   MatUpdateMPIAIJWithArray - updates an `MATMPIAIJ` matrix using an array that contains the nonzero values

4278:   Collective

4280:   Input Parameters:
4281: + mat - the matrix
4282: - v   - matrix values, stored by row

4284:   Level: intermediate

4286:   Notes:
4287:   The matrix must have been obtained with `MatCreateMPIAIJWithArrays()` or `MatMPIAIJSetPreallocationCSR()`

4289:   The column indices in the call to `MatCreateMPIAIJWithArrays()` or `MatMPIAIJSetPreallocationCSR()` must have been sorted for this call to work correctly

4291: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4292:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArrays()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4293: @*/
4294: PetscErrorCode MatUpdateMPIAIJWithArray(Mat mat, const PetscScalar v[])
4295: {
4296:   PetscInt        nnz, i, m;
4297:   PetscBool       nooffprocentries;
4298:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)mat->data;
4299:   Mat_SeqAIJ     *Ad  = (Mat_SeqAIJ *)Aij->A->data;
4300:   Mat_SeqAIJ     *Ao  = (Mat_SeqAIJ *)Aij->B->data;
4301:   PetscScalar    *ad, *ao;
4302:   const PetscInt *Adi = Ad->i, *Adj = Ao->i;
4303:   PetscInt        ldi, Iii, md;
4304:   PetscInt       *ld = Aij->ld;

4306:   PetscFunctionBegin;
4307:   m = mat->rmap->n;

4309:   PetscCall(MatSeqAIJGetArrayWrite(Aij->A, &ad));
4310:   PetscCall(MatSeqAIJGetArrayWrite(Aij->B, &ao));
4311:   Iii = 0;
4312:   for (i = 0; i < m; i++) {
4313:     nnz = Adi[i + 1] - Adi[i] + Adj[i + 1] - Adj[i];
4314:     ldi = ld[i];
4315:     md  = Adi[i + 1] - Adi[i];
4316:     PetscCall(PetscArraycpy(ad, v + Iii + ldi, md));
4317:     ad += md;
4318:     if (ao) {
4319:       PetscCall(PetscArraycpy(ao, v + Iii, ldi));
4320:       PetscCall(PetscArraycpy(ao + ldi, v + Iii + ldi + md, nnz - ldi - md));
4321:       ao += nnz - md;
4322:     }
4323:     Iii += nnz;
4324:   }
4325:   nooffprocentries      = mat->nooffprocentries;
4326:   mat->nooffprocentries = PETSC_TRUE;
4327:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->A, &ad));
4328:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->B, &ao));
4329:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->A));
4330:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->B));
4331:   PetscCall(PetscObjectStateIncrease((PetscObject)mat));
4332:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
4333:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
4334:   mat->nooffprocentries = nooffprocentries;
4335:   PetscFunctionReturn(PETSC_SUCCESS);
4336: }

4338: /*@
4339:   MatCreateAIJ - Creates a sparse parallel matrix in `MATAIJ` format
4340:   (the default parallel PETSc format).  For good matrix assembly performance
4341:   the user should preallocate the matrix storage by setting the parameters
4342:   `d_nz` (or `d_nnz`) and `o_nz` (or `o_nnz`).

4344:   Collective

4346:   Input Parameters:
4347: + comm  - MPI communicator
4348: . m     - number of local rows (or `PETSC_DECIDE` to have calculated if M is given)
4349:           This value should be the same as the local size used in creating the
4350:           y vector for the matrix-vector product y = Ax.
4351: . n     - This value should be the same as the local size used in creating the
4352:           x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4353:           calculated if N is given) For square matrices n is almost always m.
4354: . M     - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4355: . N     - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4356: . d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4357:           (same value is used for all local rows)
4358: . d_nnz - array containing the number of nonzeros in the various rows of the
4359:           DIAGONAL portion of the local submatrix (possibly different for each row)
4360:           or `NULL`, if `d_nz` is used to specify the nonzero structure.
4361:           The size of this array is equal to the number of local rows, i.e 'm'.
4362: . o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4363:           submatrix (same value is used for all local rows).
4364: - o_nnz - array containing the number of nonzeros in the various rows of the
4365:           OFF-DIAGONAL portion of the local submatrix (possibly different for
4366:           each row) or `NULL`, if `o_nz` is used to specify the nonzero
4367:           structure. The size of this array is equal to the number
4368:           of local rows, i.e 'm'.

4370:   Output Parameter:
4371: . A - the matrix

4373:   Options Database Keys:
4374: + -mat_no_inode                     - Do not use inodes
4375: . -mat_inode_limit <limit>          - Sets inode limit (max limit=5)
4376: - -matmult_vecscatter_view <viewer> - View the vecscatter (i.e., communication pattern) used in `MatMult()` of sparse parallel matrices.
4377:                                       See viewer types in manual of `MatView()`. Of them, ascii_matlab, draw or binary cause the `VecScatter`
4378:                                       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.

4380:   Level: intermediate

4382:   Notes:
4383:   It is recommended that one use `MatCreateFromOptions()` or the `MatCreate()`, `MatSetType()` and/or `MatSetFromOptions()`,
4384:   MatXXXXSetPreallocation() paradigm instead of this routine directly.
4385:   [MatXXXXSetPreallocation() is, for example, `MatSeqAIJSetPreallocation()`]

4387:   If the *_nnz parameter is given then the *_nz parameter is ignored

4389:   The `m`,`n`,`M`,`N` parameters specify the size of the matrix, and its partitioning across
4390:   processors, while `d_nz`,`d_nnz`,`o_nz`,`o_nnz` parameters specify the approximate
4391:   storage requirements for this matrix.

4393:   If `PETSC_DECIDE` or  `PETSC_DETERMINE` is used for a particular argument on one
4394:   processor than it must be used on all processors that share the object for
4395:   that argument.

4397:   If `m` and `n` are not `PETSC_DECIDE`, then the values determine the `PetscLayout` of the matrix and the ranges returned by
4398:   `MatGetOwnershipRange()`, `MatGetOwnershipRanges()`, `MatGetOwnershipRangeColumn()`, and `MatGetOwnershipRangesColumn()`.

4400:   The user MUST specify either the local or global matrix dimensions
4401:   (possibly both).

4403:   The parallel matrix is partitioned across processors such that the
4404:   first `m0` rows belong to process 0, the next `m1` rows belong to
4405:   process 1, the next `m2` rows belong to process 2, etc., where
4406:   `m0`, `m1`, `m2`... are the input parameter `m` on each MPI process. I.e., each MPI process stores
4407:   values corresponding to [m x N] submatrix.

4409:   The columns are logically partitioned with the n0 columns belonging
4410:   to 0th partition, the next n1 columns belonging to the next
4411:   partition etc.. where n0,n1,n2... are the input parameter 'n'.

4413:   The DIAGONAL portion of the local submatrix on any given processor
4414:   is the submatrix corresponding to the rows and columns m,n
4415:   corresponding to the given processor. i.e diagonal matrix on
4416:   process 0 is [m0 x n0], diagonal matrix on process 1 is [m1 x n1]
4417:   etc. The remaining portion of the local submatrix [m x (N-n)]
4418:   constitute the OFF-DIAGONAL portion. The example below better
4419:   illustrates this concept. The two matrices, the DIAGONAL portion and
4420:   the OFF-DIAGONAL portion are each stored as `MATSEQAIJ` matrices.

4422:   For a square global matrix we define each processor's diagonal portion
4423:   to be its local rows and the corresponding columns (a square submatrix);
4424:   each processor's off-diagonal portion encompasses the remainder of the
4425:   local matrix (a rectangular submatrix).

4427:   If `o_nnz`, `d_nnz` are specified, then `o_nz`, and `d_nz` are ignored.

4429:   When calling this routine with a single process communicator, a matrix of
4430:   type `MATSEQAIJ` is returned.  If a matrix of type `MATMPIAIJ` is desired for this
4431:   type of communicator, use the construction mechanism
4432: .vb
4433:   MatCreate(..., &A);
4434:   MatSetType(A, MATMPIAIJ);
4435:   MatSetSizes(A, m, n, M, N);
4436:   MatMPIAIJSetPreallocation(A, ...);
4437: .ve

4439:   By default, this format uses inodes (identical nodes) when possible.
4440:   We search for consecutive rows with the same nonzero structure, thereby
4441:   reusing matrix information to achieve increased efficiency.

4443:   Example Usage:
4444:   Consider the following 8x8 matrix with 34 non-zero values, that is
4445:   assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4446:   proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4447:   as follows

4449: .vb
4450:             1  2  0  |  0  3  0  |  0  4
4451:     Proc0   0  5  6  |  7  0  0  |  8  0
4452:             9  0 10  | 11  0  0  | 12  0
4453:     -------------------------------------
4454:            13  0 14  | 15 16 17  |  0  0
4455:     Proc1   0 18  0  | 19 20 21  |  0  0
4456:             0  0  0  | 22 23  0  | 24  0
4457:     -------------------------------------
4458:     Proc2  25 26 27  |  0  0 28  | 29  0
4459:            30  0  0  | 31 32 33  |  0 34
4460: .ve

4462:   This can be represented as a collection of submatrices as

4464: .vb
4465:       A B C
4466:       D E F
4467:       G H I
4468: .ve

4470:   Where the submatrices A,B,C are owned by proc0, D,E,F are
4471:   owned by proc1, G,H,I are owned by proc2.

4473:   The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4474:   The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4475:   The 'M','N' parameters are 8,8, and have the same values on all procs.

4477:   The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4478:   submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4479:   corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4480:   Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4481:   part as `MATSEQAIJ` matrices. For example, proc1 will store [E] as a `MATSEQAIJ`
4482:   matrix, and [DF] as another SeqAIJ matrix.

4484:   When `d_nz`, `o_nz` parameters are specified, `d_nz` storage elements are
4485:   allocated for every row of the local DIAGONAL submatrix, and `o_nz`
4486:   storage locations are allocated for every row of the OFF-DIAGONAL submatrix.
4487:   One way to choose `d_nz` and `o_nz` is to use the maximum number of nonzeros over
4488:   the local rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4489:   In this case, the values of `d_nz`,`o_nz` are
4490: .vb
4491:      proc0  dnz = 2, o_nz = 2
4492:      proc1  dnz = 3, o_nz = 2
4493:      proc2  dnz = 1, o_nz = 4
4494: .ve
4495:   We are allocating m*(`d_nz`+`o_nz`) storage locations for every proc. This
4496:   translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4497:   for proc3. i.e we are using 12+15+10=37 storage locations to store
4498:   34 values.

4500:   When `d_nnz`, `o_nnz` parameters are specified, the storage is specified
4501:   for every row, corresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4502:   In the above case the values for d_nnz,o_nnz are
4503: .vb
4504:      proc0 d_nnz = [2,2,2] and o_nnz = [2,2,2]
4505:      proc1 d_nnz = [3,3,2] and o_nnz = [2,1,1]
4506:      proc2 d_nnz = [1,1]   and o_nnz = [4,4]
4507: .ve
4508:   Here the space allocated is sum of all the above values i.e 34, and
4509:   hence pre-allocation is perfect.

4511: .seealso: [](ch_matrices), `Mat`, [Sparse Matrix Creation](sec_matsparse), `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4512:           `MATMPIAIJ`, `MatCreateMPIAIJWithArrays()`, `MatGetOwnershipRange()`, `MatGetOwnershipRanges()`, `MatGetOwnershipRangeColumn()`,
4513:           `MatGetOwnershipRangesColumn()`, `PetscLayout`
4514: @*/
4515: 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)
4516: {
4517:   PetscMPIInt size;

4519:   PetscFunctionBegin;
4520:   PetscCall(MatCreate(comm, A));
4521:   PetscCall(MatSetSizes(*A, m, n, M, N));
4522:   PetscCallMPI(MPI_Comm_size(comm, &size));
4523:   if (size > 1) {
4524:     PetscCall(MatSetType(*A, MATMPIAIJ));
4525:     PetscCall(MatMPIAIJSetPreallocation(*A, d_nz, d_nnz, o_nz, o_nnz));
4526:   } else {
4527:     PetscCall(MatSetType(*A, MATSEQAIJ));
4528:     PetscCall(MatSeqAIJSetPreallocation(*A, d_nz, d_nnz));
4529:   }
4530:   PetscFunctionReturn(PETSC_SUCCESS);
4531: }

4533: /*@C
4534:   MatMPIAIJGetSeqAIJ - Returns the local pieces of this distributed matrix

4536:   Not Collective

4538:   Input Parameter:
4539: . A - The `MATMPIAIJ` matrix

4541:   Output Parameters:
4542: + Ad     - The local diagonal block as a `MATSEQAIJ` matrix
4543: . Ao     - The local off-diagonal block as a `MATSEQAIJ` matrix
4544: - colmap - An array mapping local column numbers of `Ao` to global column numbers of the parallel matrix

4546:   Level: intermediate

4548:   Note:
4549:   The rows in `Ad` and `Ao` are in [0, Nr), where Nr is the number of local rows on this process. The columns
4550:   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
4551:   the number of nonzero columns in the local off-diagonal piece of the matrix `A`. The array colmap maps these
4552:   local column numbers to global column numbers in the original matrix.

4554: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatMPIAIJGetLocalMat()`, `MatMPIAIJGetLocalMatCondensed()`, `MatCreateAIJ()`, `MATSEQAIJ`
4555: @*/
4556: PetscErrorCode MatMPIAIJGetSeqAIJ(Mat A, Mat *Ad, Mat *Ao, const PetscInt *colmap[])
4557: {
4558:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
4559:   PetscBool   flg;

4561:   PetscFunctionBegin;
4562:   PetscCall(PetscStrbeginswith(((PetscObject)A)->type_name, MATMPIAIJ, &flg));
4563:   PetscCheck(flg, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "This function requires a MATMPIAIJ matrix as input");
4564:   if (Ad) *Ad = a->A;
4565:   if (Ao) *Ao = a->B;
4566:   if (colmap) *colmap = a->garray;
4567:   PetscFunctionReturn(PETSC_SUCCESS);
4568: }

4570: PetscErrorCode MatCreateMPIMatConcatenateSeqMat_MPIAIJ(MPI_Comm comm, Mat inmat, PetscInt n, MatReuse scall, Mat *outmat)
4571: {
4572:   PetscInt     m, N, i, rstart, nnz, Ii;
4573:   PetscInt    *indx;
4574:   PetscScalar *values;
4575:   MatType      rootType;

4577:   PetscFunctionBegin;
4578:   PetscCall(MatGetSize(inmat, &m, &N));
4579:   if (scall == MAT_INITIAL_MATRIX) { /* symbolic phase */
4580:     PetscInt *dnz, *onz, sum, bs, cbs;

4582:     if (n == PETSC_DECIDE) PetscCall(PetscSplitOwnership(comm, &n, &N));
4583:     /* Check sum(n) = N */
4584:     PetscCallMPI(MPIU_Allreduce(&n, &sum, 1, MPIU_INT, MPI_SUM, comm));
4585:     PetscCheck(sum == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Sum of local columns %" PetscInt_FMT " != global columns %" PetscInt_FMT, sum, N);

4587:     PetscCallMPI(MPI_Scan(&m, &rstart, 1, MPIU_INT, MPI_SUM, comm));
4588:     rstart -= m;

4590:     MatPreallocateBegin(comm, m, n, dnz, onz);
4591:     for (i = 0; i < m; i++) {
4592:       PetscCall(MatGetRow_SeqAIJ(inmat, i, &nnz, &indx, NULL));
4593:       PetscCall(MatPreallocateSet(i + rstart, nnz, indx, dnz, onz));
4594:       PetscCall(MatRestoreRow_SeqAIJ(inmat, i, &nnz, &indx, NULL));
4595:     }

4597:     PetscCall(MatCreate(comm, outmat));
4598:     PetscCall(MatSetSizes(*outmat, m, n, PETSC_DETERMINE, PETSC_DETERMINE));
4599:     PetscCall(MatGetBlockSizes(inmat, &bs, &cbs));
4600:     PetscCall(MatSetBlockSizes(*outmat, bs, cbs));
4601:     PetscCall(MatGetRootType_Private(inmat, &rootType));
4602:     PetscCall(MatSetType(*outmat, rootType));
4603:     PetscCall(MatSeqAIJSetPreallocation(*outmat, 0, dnz));
4604:     PetscCall(MatMPIAIJSetPreallocation(*outmat, 0, dnz, 0, onz));
4605:     MatPreallocateEnd(dnz, onz);
4606:     PetscCall(MatSetOption(*outmat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
4607:   }

4609:   /* numeric phase */
4610:   PetscCall(MatGetOwnershipRange(*outmat, &rstart, NULL));
4611:   for (i = 0; i < m; i++) {
4612:     PetscCall(MatGetRow_SeqAIJ(inmat, i, &nnz, &indx, &values));
4613:     Ii = i + rstart;
4614:     PetscCall(MatSetValues(*outmat, 1, &Ii, nnz, indx, values, INSERT_VALUES));
4615:     PetscCall(MatRestoreRow_SeqAIJ(inmat, i, &nnz, &indx, &values));
4616:   }
4617:   PetscCall(MatAssemblyBegin(*outmat, MAT_FINAL_ASSEMBLY));
4618:   PetscCall(MatAssemblyEnd(*outmat, MAT_FINAL_ASSEMBLY));
4619:   PetscFunctionReturn(PETSC_SUCCESS);
4620: }

4622: static PetscErrorCode MatMergeSeqsToMPIDestroy(void **data)
4623: {
4624:   MatMergeSeqsToMPI *merge = (MatMergeSeqsToMPI *)*data;

4626:   PetscFunctionBegin;
4627:   if (!merge) PetscFunctionReturn(PETSC_SUCCESS);
4628:   PetscCall(PetscFree(merge->id_r));
4629:   PetscCall(PetscFree(merge->len_s));
4630:   PetscCall(PetscFree(merge->len_r));
4631:   PetscCall(PetscFree(merge->bi));
4632:   PetscCall(PetscFree(merge->bj));
4633:   PetscCall(PetscFree(merge->buf_ri[0]));
4634:   PetscCall(PetscFree(merge->buf_ri));
4635:   PetscCall(PetscFree(merge->buf_rj[0]));
4636:   PetscCall(PetscFree(merge->buf_rj));
4637:   PetscCall(PetscFree(merge->coi));
4638:   PetscCall(PetscFree(merge->coj));
4639:   PetscCall(PetscFree(merge->owners_co));
4640:   PetscCall(PetscLayoutDestroy(&merge->rowmap));
4641:   PetscCall(PetscFree(merge));
4642:   PetscFunctionReturn(PETSC_SUCCESS);
4643: }

4645: #include <../src/mat/utils/freespace.h>
4646: #include <petscbt.h>

4648: PetscErrorCode MatCreateMPIAIJSumSeqAIJNumeric(Mat seqmat, Mat mpimat)
4649: {
4650:   MPI_Comm           comm;
4651:   Mat_SeqAIJ        *a = (Mat_SeqAIJ *)seqmat->data;
4652:   PetscMPIInt        size, rank, taga, *len_s;
4653:   PetscInt           N = mpimat->cmap->N, i, j, *owners, *ai = a->i, *aj, m;
4654:   PetscMPIInt        proc, k;
4655:   PetscInt         **buf_ri, **buf_rj;
4656:   PetscInt           anzi, *bj_i, *bi, *bj, arow, bnzi, nextaj;
4657:   PetscInt           nrows, **buf_ri_k, **nextrow, **nextai;
4658:   MPI_Request       *s_waits, *r_waits;
4659:   MPI_Status        *status;
4660:   const MatScalar   *aa, *a_a;
4661:   MatScalar        **abuf_r, *ba_i;
4662:   MatMergeSeqsToMPI *merge;
4663:   PetscContainer     container;

4665:   PetscFunctionBegin;
4666:   PetscCall(PetscObjectGetComm((PetscObject)mpimat, &comm));
4667:   PetscCall(PetscLogEventBegin(MAT_Seqstompinum, seqmat, 0, 0, 0));

4669:   PetscCallMPI(MPI_Comm_size(comm, &size));
4670:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

4672:   PetscCall(PetscObjectQuery((PetscObject)mpimat, "MatMergeSeqsToMPI", (PetscObject *)&container));
4673:   PetscCheck(container, PetscObjectComm((PetscObject)mpimat), PETSC_ERR_PLIB, "Mat not created from MatCreateMPIAIJSumSeqAIJSymbolic");
4674:   PetscCall(PetscContainerGetPointer(container, (void **)&merge));
4675:   PetscCall(MatSeqAIJGetArrayRead(seqmat, &a_a));
4676:   aa = a_a;

4678:   bi     = merge->bi;
4679:   bj     = merge->bj;
4680:   buf_ri = merge->buf_ri;
4681:   buf_rj = merge->buf_rj;

4683:   PetscCall(PetscMalloc1(size, &status));
4684:   owners = merge->rowmap->range;
4685:   len_s  = merge->len_s;

4687:   /* send and recv matrix values */
4688:   PetscCall(PetscObjectGetNewTag((PetscObject)mpimat, &taga));
4689:   PetscCall(PetscPostIrecvScalar(comm, taga, merge->nrecv, merge->id_r, merge->len_r, &abuf_r, &r_waits));

4691:   PetscCall(PetscMalloc1(merge->nsend + 1, &s_waits));
4692:   for (proc = 0, k = 0; proc < size; proc++) {
4693:     if (!len_s[proc]) continue;
4694:     i = owners[proc];
4695:     PetscCallMPI(MPIU_Isend(aa + ai[i], len_s[proc], MPIU_MATSCALAR, proc, taga, comm, s_waits + k));
4696:     k++;
4697:   }

4699:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, r_waits, status));
4700:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, s_waits, status));
4701:   PetscCall(PetscFree(status));

4703:   PetscCall(PetscFree(s_waits));
4704:   PetscCall(PetscFree(r_waits));

4706:   /* insert mat values of mpimat */
4707:   PetscCall(PetscMalloc1(N, &ba_i));
4708:   PetscCall(PetscMalloc3(merge->nrecv, &buf_ri_k, merge->nrecv, &nextrow, merge->nrecv, &nextai));

4710:   for (k = 0; k < merge->nrecv; k++) {
4711:     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4712:     nrows       = *buf_ri_k[k];
4713:     nextrow[k]  = buf_ri_k[k] + 1;           /* next row number of k-th recved i-structure */
4714:     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* points to the next i-structure of k-th recved i-structure  */
4715:   }

4717:   /* set values of ba */
4718:   m = merge->rowmap->n;
4719:   for (i = 0; i < m; i++) {
4720:     arow = owners[rank] + i;
4721:     bj_i = bj + bi[i]; /* col indices of the i-th row of mpimat */
4722:     bnzi = bi[i + 1] - bi[i];
4723:     PetscCall(PetscArrayzero(ba_i, bnzi));

4725:     /* add local non-zero vals of this proc's seqmat into ba */
4726:     anzi   = ai[arow + 1] - ai[arow];
4727:     aj     = a->j + ai[arow];
4728:     aa     = a_a + ai[arow];
4729:     nextaj = 0;
4730:     for (j = 0; nextaj < anzi; j++) {
4731:       if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4732:         ba_i[j] += aa[nextaj++];
4733:       }
4734:     }

4736:     /* add received vals into ba */
4737:     for (k = 0; k < merge->nrecv; k++) { /* k-th received message */
4738:       /* i-th row */
4739:       if (i == *nextrow[k]) {
4740:         anzi   = *(nextai[k] + 1) - *nextai[k];
4741:         aj     = buf_rj[k] + *nextai[k];
4742:         aa     = abuf_r[k] + *nextai[k];
4743:         nextaj = 0;
4744:         for (j = 0; nextaj < anzi; j++) {
4745:           if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4746:             ba_i[j] += aa[nextaj++];
4747:           }
4748:         }
4749:         nextrow[k]++;
4750:         nextai[k]++;
4751:       }
4752:     }
4753:     PetscCall(MatSetValues(mpimat, 1, &arow, bnzi, bj_i, ba_i, INSERT_VALUES));
4754:   }
4755:   PetscCall(MatSeqAIJRestoreArrayRead(seqmat, &a_a));
4756:   PetscCall(MatAssemblyBegin(mpimat, MAT_FINAL_ASSEMBLY));
4757:   PetscCall(MatAssemblyEnd(mpimat, MAT_FINAL_ASSEMBLY));

4759:   PetscCall(PetscFree(abuf_r[0]));
4760:   PetscCall(PetscFree(abuf_r));
4761:   PetscCall(PetscFree(ba_i));
4762:   PetscCall(PetscFree3(buf_ri_k, nextrow, nextai));
4763:   PetscCall(PetscLogEventEnd(MAT_Seqstompinum, seqmat, 0, 0, 0));
4764:   PetscFunctionReturn(PETSC_SUCCESS);
4765: }

4767: PetscErrorCode MatCreateMPIAIJSumSeqAIJSymbolic(MPI_Comm comm, Mat seqmat, PetscInt m, PetscInt n, Mat *mpimat)
4768: {
4769:   Mat                B_mpi;
4770:   Mat_SeqAIJ        *a = (Mat_SeqAIJ *)seqmat->data;
4771:   PetscMPIInt        size, rank, tagi, tagj, *len_s, *len_si, *len_ri;
4772:   PetscInt         **buf_rj, **buf_ri, **buf_ri_k;
4773:   PetscInt           M = seqmat->rmap->n, N = seqmat->cmap->n, i, *owners, *ai = a->i, *aj = a->j;
4774:   PetscInt           len, *dnz, *onz, bs, cbs;
4775:   PetscInt           k, anzi, *bi, *bj, *lnk, nlnk, arow, bnzi;
4776:   PetscInt           nrows, *buf_s, *buf_si, *buf_si_i, **nextrow, **nextai;
4777:   MPI_Request       *si_waits, *sj_waits, *ri_waits, *rj_waits;
4778:   MPI_Status        *status;
4779:   PetscFreeSpaceList free_space = NULL, current_space = NULL;
4780:   PetscBT            lnkbt;
4781:   MatMergeSeqsToMPI *merge;
4782:   PetscContainer     container;

4784:   PetscFunctionBegin;
4785:   PetscCall(PetscLogEventBegin(MAT_Seqstompisym, seqmat, 0, 0, 0));

4787:   /* make sure it is a PETSc comm */
4788:   PetscCall(PetscCommDuplicate(comm, &comm, NULL));
4789:   PetscCallMPI(MPI_Comm_size(comm, &size));
4790:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

4792:   PetscCall(PetscNew(&merge));
4793:   PetscCall(PetscMalloc1(size, &status));

4795:   /* determine row ownership */
4796:   PetscCall(PetscLayoutCreate(comm, &merge->rowmap));
4797:   PetscCall(PetscLayoutSetLocalSize(merge->rowmap, m));
4798:   PetscCall(PetscLayoutSetSize(merge->rowmap, M));
4799:   PetscCall(PetscLayoutSetBlockSize(merge->rowmap, 1));
4800:   PetscCall(PetscLayoutSetUp(merge->rowmap));
4801:   PetscCall(PetscMalloc1(size, &len_si));
4802:   PetscCall(PetscMalloc1(size, &merge->len_s));

4804:   m      = merge->rowmap->n;
4805:   owners = merge->rowmap->range;

4807:   /* determine the number of messages to send, their lengths */
4808:   len_s = merge->len_s;

4810:   len          = 0; /* length of buf_si[] */
4811:   merge->nsend = 0;
4812:   for (PetscMPIInt proc = 0; proc < size; proc++) {
4813:     len_si[proc] = 0;
4814:     if (proc == rank) {
4815:       len_s[proc] = 0;
4816:     } else {
4817:       PetscCall(PetscMPIIntCast(owners[proc + 1] - owners[proc] + 1, &len_si[proc]));
4818:       PetscCall(PetscMPIIntCast(ai[owners[proc + 1]] - ai[owners[proc]], &len_s[proc])); /* num of rows to be sent to [proc] */
4819:     }
4820:     if (len_s[proc]) {
4821:       merge->nsend++;
4822:       nrows = 0;
4823:       for (i = owners[proc]; i < owners[proc + 1]; i++) {
4824:         if (ai[i + 1] > ai[i]) nrows++;
4825:       }
4826:       PetscCall(PetscMPIIntCast(2 * (nrows + 1), &len_si[proc]));
4827:       len += len_si[proc];
4828:     }
4829:   }

4831:   /* determine the number and length of messages to receive for ij-structure */
4832:   PetscCall(PetscGatherNumberOfMessages(comm, NULL, len_s, &merge->nrecv));
4833:   PetscCall(PetscGatherMessageLengths2(comm, merge->nsend, merge->nrecv, len_s, len_si, &merge->id_r, &merge->len_r, &len_ri));

4835:   /* post the Irecv of j-structure */
4836:   PetscCall(PetscCommGetNewTag(comm, &tagj));
4837:   PetscCall(PetscPostIrecvInt(comm, tagj, merge->nrecv, merge->id_r, merge->len_r, &buf_rj, &rj_waits));

4839:   /* post the Isend of j-structure */
4840:   PetscCall(PetscMalloc2(merge->nsend, &si_waits, merge->nsend, &sj_waits));

4842:   for (PetscMPIInt proc = 0, k = 0; proc < size; proc++) {
4843:     if (!len_s[proc]) continue;
4844:     i = owners[proc];
4845:     PetscCallMPI(MPIU_Isend(aj + ai[i], len_s[proc], MPIU_INT, proc, tagj, comm, sj_waits + k));
4846:     k++;
4847:   }

4849:   /* receives and sends of j-structure are complete */
4850:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, rj_waits, status));
4851:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, sj_waits, status));

4853:   /* send and recv i-structure */
4854:   PetscCall(PetscCommGetNewTag(comm, &tagi));
4855:   PetscCall(PetscPostIrecvInt(comm, tagi, merge->nrecv, merge->id_r, len_ri, &buf_ri, &ri_waits));

4857:   PetscCall(PetscMalloc1(len + 1, &buf_s));
4858:   buf_si = buf_s; /* points to the beginning of k-th msg to be sent */
4859:   for (PetscMPIInt proc = 0, k = 0; proc < size; proc++) {
4860:     if (!len_s[proc]) continue;
4861:     /* form outgoing message for i-structure:
4862:          buf_si[0]:                 nrows to be sent
4863:                [1:nrows]:           row index (global)
4864:                [nrows+1:2*nrows+1]: i-structure index
4865:     */
4866:     nrows       = len_si[proc] / 2 - 1;
4867:     buf_si_i    = buf_si + nrows + 1;
4868:     buf_si[0]   = nrows;
4869:     buf_si_i[0] = 0;
4870:     nrows       = 0;
4871:     for (i = owners[proc]; i < owners[proc + 1]; i++) {
4872:       anzi = ai[i + 1] - ai[i];
4873:       if (anzi) {
4874:         buf_si_i[nrows + 1] = buf_si_i[nrows] + anzi; /* i-structure */
4875:         buf_si[nrows + 1]   = i - owners[proc];       /* local row index */
4876:         nrows++;
4877:       }
4878:     }
4879:     PetscCallMPI(MPIU_Isend(buf_si, len_si[proc], MPIU_INT, proc, tagi, comm, si_waits + k));
4880:     k++;
4881:     buf_si += len_si[proc];
4882:   }

4884:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, ri_waits, status));
4885:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, si_waits, status));

4887:   PetscCall(PetscInfo(seqmat, "nsend: %d, nrecv: %d\n", merge->nsend, merge->nrecv));
4888:   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]));

4890:   PetscCall(PetscFree(len_si));
4891:   PetscCall(PetscFree(len_ri));
4892:   PetscCall(PetscFree(rj_waits));
4893:   PetscCall(PetscFree2(si_waits, sj_waits));
4894:   PetscCall(PetscFree(ri_waits));
4895:   PetscCall(PetscFree(buf_s));
4896:   PetscCall(PetscFree(status));

4898:   /* compute a local seq matrix in each processor */
4899:   /* allocate bi array and free space for accumulating nonzero column info */
4900:   PetscCall(PetscMalloc1(m + 1, &bi));
4901:   bi[0] = 0;

4903:   /* create and initialize a linked list */
4904:   nlnk = N + 1;
4905:   PetscCall(PetscLLCreate(N, N, nlnk, lnk, lnkbt));

4907:   /* initial FreeSpace size is 2*(num of local nnz(seqmat)) */
4908:   len = ai[owners[rank + 1]] - ai[owners[rank]];
4909:   PetscCall(PetscFreeSpaceGet(PetscIntMultTruncate(2, len) + 1, &free_space));

4911:   current_space = free_space;

4913:   /* determine symbolic info for each local row */
4914:   PetscCall(PetscMalloc3(merge->nrecv, &buf_ri_k, merge->nrecv, &nextrow, merge->nrecv, &nextai));

4916:   for (k = 0; k < merge->nrecv; k++) {
4917:     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4918:     nrows       = *buf_ri_k[k];
4919:     nextrow[k]  = buf_ri_k[k] + 1;           /* next row number of k-th recved i-structure */
4920:     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* points to the next i-structure of k-th recved i-structure  */
4921:   }

4923:   MatPreallocateBegin(comm, m, n, dnz, onz);
4924:   len = 0;
4925:   for (i = 0; i < m; i++) {
4926:     bnzi = 0;
4927:     /* add local non-zero cols of this proc's seqmat into lnk */
4928:     arow = owners[rank] + i;
4929:     anzi = ai[arow + 1] - ai[arow];
4930:     aj   = a->j + ai[arow];
4931:     PetscCall(PetscLLAddSorted(anzi, aj, N, &nlnk, lnk, lnkbt));
4932:     bnzi += nlnk;
4933:     /* add received col data into lnk */
4934:     for (k = 0; k < merge->nrecv; k++) { /* k-th received message */
4935:       if (i == *nextrow[k]) {            /* i-th row */
4936:         anzi = *(nextai[k] + 1) - *nextai[k];
4937:         aj   = buf_rj[k] + *nextai[k];
4938:         PetscCall(PetscLLAddSorted(anzi, aj, N, &nlnk, lnk, lnkbt));
4939:         bnzi += nlnk;
4940:         nextrow[k]++;
4941:         nextai[k]++;
4942:       }
4943:     }
4944:     if (len < bnzi) len = bnzi; /* =max(bnzi) */

4946:     /* if free space is not available, make more free space */
4947:     if (current_space->local_remaining < bnzi) PetscCall(PetscFreeSpaceGet(PetscIntSumTruncate(bnzi, current_space->total_array_size), &current_space));
4948:     /* copy data into free space, then initialize lnk */
4949:     PetscCall(PetscLLClean(N, N, bnzi, lnk, current_space->array, lnkbt));
4950:     PetscCall(MatPreallocateSet(i + owners[rank], bnzi, current_space->array, dnz, onz));

4952:     current_space->array += bnzi;
4953:     current_space->local_used += bnzi;
4954:     current_space->local_remaining -= bnzi;

4956:     bi[i + 1] = bi[i] + bnzi;
4957:   }

4959:   PetscCall(PetscFree3(buf_ri_k, nextrow, nextai));

4961:   PetscCall(PetscMalloc1(bi[m], &bj));
4962:   PetscCall(PetscFreeSpaceContiguous(&free_space, bj));
4963:   PetscCall(PetscLLDestroy(lnk, lnkbt));

4965:   /* create symbolic parallel matrix B_mpi */
4966:   PetscCall(MatGetBlockSizes(seqmat, &bs, &cbs));
4967:   PetscCall(MatCreate(comm, &B_mpi));
4968:   if (n == PETSC_DECIDE) {
4969:     PetscCall(MatSetSizes(B_mpi, m, n, PETSC_DETERMINE, N));
4970:   } else {
4971:     PetscCall(MatSetSizes(B_mpi, m, n, PETSC_DETERMINE, PETSC_DETERMINE));
4972:   }
4973:   PetscCall(MatSetBlockSizes(B_mpi, bs, cbs));
4974:   PetscCall(MatSetType(B_mpi, MATMPIAIJ));
4975:   PetscCall(MatMPIAIJSetPreallocation(B_mpi, 0, dnz, 0, onz));
4976:   MatPreallocateEnd(dnz, onz);
4977:   PetscCall(MatSetOption(B_mpi, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_FALSE));

4979:   /* B_mpi is not ready for use - assembly will be done by MatCreateMPIAIJSumSeqAIJNumeric() */
4980:   B_mpi->assembled = PETSC_FALSE;
4981:   merge->bi        = bi;
4982:   merge->bj        = bj;
4983:   merge->buf_ri    = buf_ri;
4984:   merge->buf_rj    = buf_rj;
4985:   merge->coi       = NULL;
4986:   merge->coj       = NULL;
4987:   merge->owners_co = NULL;

4989:   PetscCall(PetscCommDestroy(&comm));

4991:   /* attach the supporting struct to B_mpi for reuse */
4992:   PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &container));
4993:   PetscCall(PetscContainerSetPointer(container, merge));
4994:   PetscCall(PetscContainerSetCtxDestroy(container, MatMergeSeqsToMPIDestroy));
4995:   PetscCall(PetscObjectCompose((PetscObject)B_mpi, "MatMergeSeqsToMPI", (PetscObject)container));
4996:   PetscCall(PetscContainerDestroy(&container));
4997:   *mpimat = B_mpi;

4999:   PetscCall(PetscLogEventEnd(MAT_Seqstompisym, seqmat, 0, 0, 0));
5000:   PetscFunctionReturn(PETSC_SUCCESS);
5001: }

5003: /*@
5004:   MatCreateMPIAIJSumSeqAIJ - Creates a `MATMPIAIJ` matrix by adding sequential
5005:   matrices from each processor

5007:   Collective

5009:   Input Parameters:
5010: + comm   - the communicators the parallel matrix will live on
5011: . seqmat - the input sequential matrices
5012: . m      - number of local rows (or `PETSC_DECIDE`)
5013: . n      - number of local columns (or `PETSC_DECIDE`)
5014: - scall  - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5016:   Output Parameter:
5017: . mpimat - the parallel matrix generated

5019:   Level: advanced

5021:   Note:
5022:   The dimensions of the sequential matrix in each processor MUST be the same.
5023:   The input seqmat is included into the container `MatMergeSeqsToMPIDestroy`, and will be
5024:   destroyed when `mpimat` is destroyed. Call `PetscObjectQuery()` to access `seqmat`.

5026: .seealso: [](ch_matrices), `Mat`, `MatCreateAIJ()`
5027: @*/
5028: PetscErrorCode MatCreateMPIAIJSumSeqAIJ(MPI_Comm comm, Mat seqmat, PetscInt m, PetscInt n, MatReuse scall, Mat *mpimat)
5029: {
5030:   PetscMPIInt size;

5032:   PetscFunctionBegin;
5033:   PetscCallMPI(MPI_Comm_size(comm, &size));
5034:   if (size == 1) {
5035:     PetscCall(PetscLogEventBegin(MAT_Seqstompi, seqmat, 0, 0, 0));
5036:     if (scall == MAT_INITIAL_MATRIX) {
5037:       PetscCall(MatDuplicate(seqmat, MAT_COPY_VALUES, mpimat));
5038:     } else {
5039:       PetscCall(MatCopy(seqmat, *mpimat, SAME_NONZERO_PATTERN));
5040:     }
5041:     PetscCall(PetscLogEventEnd(MAT_Seqstompi, seqmat, 0, 0, 0));
5042:     PetscFunctionReturn(PETSC_SUCCESS);
5043:   }
5044:   PetscCall(PetscLogEventBegin(MAT_Seqstompi, seqmat, 0, 0, 0));
5045:   if (scall == MAT_INITIAL_MATRIX) PetscCall(MatCreateMPIAIJSumSeqAIJSymbolic(comm, seqmat, m, n, mpimat));
5046:   PetscCall(MatCreateMPIAIJSumSeqAIJNumeric(seqmat, *mpimat));
5047:   PetscCall(PetscLogEventEnd(MAT_Seqstompi, seqmat, 0, 0, 0));
5048:   PetscFunctionReturn(PETSC_SUCCESS);
5049: }

5051: /*@
5052:   MatAIJGetLocalMat - Creates a `MATSEQAIJ` from a `MATAIJ` matrix.

5054:   Not Collective

5056:   Input Parameter:
5057: . A - the matrix

5059:   Output Parameter:
5060: . A_loc - the local sequential matrix generated

5062:   Level: developer

5064:   Notes:
5065:   The matrix is created by taking `A`'s local rows and putting them into a sequential matrix
5066:   with `mlocal` rows and `n` columns. Where `mlocal` is obtained with `MatGetLocalSize()` and
5067:   `n` is the global column count obtained with `MatGetSize()`

5069:   In other words combines the two parts of a parallel `MATMPIAIJ` matrix on each process to a single matrix.

5071:   For parallel matrices this creates an entirely new matrix. If the matrix is sequential it merely increases the reference count.

5073:   Destroy the matrix with `MatDestroy()`

5075: .seealso: [](ch_matrices), `Mat`, `MatMPIAIJGetLocalMat()`
5076: @*/
5077: PetscErrorCode MatAIJGetLocalMat(Mat A, Mat *A_loc)
5078: {
5079:   PetscBool mpi;

5081:   PetscFunctionBegin;
5082:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATMPIAIJ, &mpi));
5083:   if (mpi) {
5084:     PetscCall(MatMPIAIJGetLocalMat(A, MAT_INITIAL_MATRIX, A_loc));
5085:   } else {
5086:     *A_loc = A;
5087:     PetscCall(PetscObjectReference((PetscObject)*A_loc));
5088:   }
5089:   PetscFunctionReturn(PETSC_SUCCESS);
5090: }

5092: /*@
5093:   MatMPIAIJGetLocalMat - Creates a `MATSEQAIJ` from a `MATMPIAIJ` matrix.

5095:   Not Collective

5097:   Input Parameters:
5098: + A     - the matrix
5099: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5101:   Output Parameter:
5102: . A_loc - the local sequential matrix generated

5104:   Level: developer

5106:   Notes:
5107:   The matrix is created by taking all `A`'s local rows and putting them into a sequential
5108:   matrix with `mlocal` rows and `n` columns.`mlocal` is the row count obtained with
5109:   `MatGetLocalSize()` and `n` is the global column count obtained with `MatGetSize()`.

5111:   In other words combines the two parts of a parallel `MATMPIAIJ` matrix on each process to a single matrix.

5113:   When `A` is sequential and `MAT_INITIAL_MATRIX` is requested, the matrix returned is the diagonal part of `A` (which contains the entire matrix),
5114:   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
5115:   then `MatCopy`(Adiag,*`A_loc`,`SAME_NONZERO_PATTERN`) is called to fill `A_loc`. Thus one can preallocate the appropriate sequential matrix `A_loc`
5116:   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.

5118: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMatCondensed()`, `MatMPIAIJGetLocalMatMerge()`
5119: @*/
5120: PetscErrorCode MatMPIAIJGetLocalMat(Mat A, MatReuse scall, Mat *A_loc)
5121: {
5122:   Mat_MPIAIJ        *mpimat = (Mat_MPIAIJ *)A->data;
5123:   Mat_SeqAIJ        *mat, *a, *b;
5124:   PetscInt          *ai, *aj, *bi, *bj, *cmap = mpimat->garray;
5125:   const PetscScalar *aa, *ba, *aav, *bav;
5126:   PetscScalar       *ca, *cam;
5127:   PetscMPIInt        size;
5128:   PetscInt           am = A->rmap->n, i, j, k, cstart = A->cmap->rstart;
5129:   PetscInt          *ci, *cj, col, ncols_d, ncols_o, jo;
5130:   PetscBool          match;

5132:   PetscFunctionBegin;
5133:   PetscCall(PetscStrbeginswith(((PetscObject)A)->type_name, MATMPIAIJ, &match));
5134:   PetscCheck(match, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Requires MATMPIAIJ matrix as input");
5135:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)A), &size));
5136:   if (size == 1) {
5137:     if (scall == MAT_INITIAL_MATRIX) {
5138:       PetscCall(PetscObjectReference((PetscObject)mpimat->A));
5139:       *A_loc = mpimat->A;
5140:     } else if (scall == MAT_REUSE_MATRIX) {
5141:       PetscCall(MatCopy(mpimat->A, *A_loc, SAME_NONZERO_PATTERN));
5142:     }
5143:     PetscFunctionReturn(PETSC_SUCCESS);
5144:   }

5146:   PetscCall(PetscLogEventBegin(MAT_Getlocalmat, A, 0, 0, 0));
5147:   a  = (Mat_SeqAIJ *)mpimat->A->data;
5148:   b  = (Mat_SeqAIJ *)mpimat->B->data;
5149:   ai = a->i;
5150:   aj = a->j;
5151:   bi = b->i;
5152:   bj = b->j;
5153:   PetscCall(MatSeqAIJGetArrayRead(mpimat->A, &aav));
5154:   PetscCall(MatSeqAIJGetArrayRead(mpimat->B, &bav));
5155:   aa = aav;
5156:   ba = bav;
5157:   if (scall == MAT_INITIAL_MATRIX) {
5158:     PetscCall(PetscMalloc1(1 + am, &ci));
5159:     ci[0] = 0;
5160:     for (i = 0; i < am; i++) ci[i + 1] = ci[i] + (ai[i + 1] - ai[i]) + (bi[i + 1] - bi[i]);
5161:     PetscCall(PetscMalloc1(1 + ci[am], &cj));
5162:     PetscCall(PetscMalloc1(1 + ci[am], &ca));
5163:     k = 0;
5164:     for (i = 0; i < am; i++) {
5165:       ncols_o = bi[i + 1] - bi[i];
5166:       ncols_d = ai[i + 1] - ai[i];
5167:       /* off-diagonal portion of A */
5168:       for (jo = 0; jo < ncols_o; jo++) {
5169:         col = cmap[*bj];
5170:         if (col >= cstart) break;
5171:         cj[k] = col;
5172:         bj++;
5173:         ca[k++] = *ba++;
5174:       }
5175:       /* diagonal portion of A */
5176:       for (j = 0; j < ncols_d; j++) {
5177:         cj[k]   = cstart + *aj++;
5178:         ca[k++] = *aa++;
5179:       }
5180:       /* off-diagonal portion of A */
5181:       for (j = jo; j < ncols_o; j++) {
5182:         cj[k]   = cmap[*bj++];
5183:         ca[k++] = *ba++;
5184:       }
5185:     }
5186:     /* put together the new matrix */
5187:     PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, am, A->cmap->N, ci, cj, ca, A_loc));
5188:     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5189:     /* Since these are PETSc arrays, change flags to free them as necessary. */
5190:     mat          = (Mat_SeqAIJ *)(*A_loc)->data;
5191:     mat->free_a  = PETSC_TRUE;
5192:     mat->free_ij = PETSC_TRUE;
5193:     mat->nonew   = 0;
5194:   } else if (scall == MAT_REUSE_MATRIX) {
5195:     mat = (Mat_SeqAIJ *)(*A_loc)->data;
5196:     ci  = mat->i;
5197:     cj  = mat->j;
5198:     PetscCall(MatSeqAIJGetArrayWrite(*A_loc, &cam));
5199:     for (i = 0; i < am; i++) {
5200:       /* off-diagonal portion of A */
5201:       ncols_o = bi[i + 1] - bi[i];
5202:       for (jo = 0; jo < ncols_o; jo++) {
5203:         col = cmap[*bj];
5204:         if (col >= cstart) break;
5205:         *cam++ = *ba++;
5206:         bj++;
5207:       }
5208:       /* diagonal portion of A */
5209:       ncols_d = ai[i + 1] - ai[i];
5210:       for (j = 0; j < ncols_d; j++) *cam++ = *aa++;
5211:       /* off-diagonal portion of A */
5212:       for (j = jo; j < ncols_o; j++) {
5213:         *cam++ = *ba++;
5214:         bj++;
5215:       }
5216:     }
5217:     PetscCall(MatSeqAIJRestoreArrayWrite(*A_loc, &cam));
5218:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid MatReuse %d", (int)scall);
5219:   PetscCall(MatSeqAIJRestoreArrayRead(mpimat->A, &aav));
5220:   PetscCall(MatSeqAIJRestoreArrayRead(mpimat->B, &bav));
5221:   PetscCall(PetscLogEventEnd(MAT_Getlocalmat, A, 0, 0, 0));
5222:   PetscFunctionReturn(PETSC_SUCCESS);
5223: }

5225: /*@
5226:   MatMPIAIJGetLocalMatMerge - Creates a `MATSEQAIJ` from a `MATMPIAIJ` matrix by taking all its local rows and putting them into a sequential matrix with
5227:   mlocal rows and n columns. Where n is the sum of the number of columns of the diagonal and off-diagonal part

5229:   Not Collective

5231:   Input Parameters:
5232: + A     - the matrix
5233: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5235:   Output Parameters:
5236: + glob  - sequential `IS` with global indices associated with the columns of the local sequential matrix generated (can be `NULL`)
5237: - A_loc - the local sequential matrix generated

5239:   Level: developer

5241:   Note:
5242:   This is different from `MatMPIAIJGetLocalMat()` since the first columns in the returning matrix are those associated with the diagonal
5243:   part, then those associated with the off-diagonal part (in its local ordering)

5245: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMat()`, `MatMPIAIJGetLocalMatCondensed()`
5246: @*/
5247: PetscErrorCode MatMPIAIJGetLocalMatMerge(Mat A, MatReuse scall, IS *glob, Mat *A_loc)
5248: {
5249:   Mat             Ao, Ad;
5250:   const PetscInt *cmap;
5251:   PetscMPIInt     size;
5252:   PetscErrorCode (*f)(Mat, MatReuse, IS *, Mat *);

5254:   PetscFunctionBegin;
5255:   PetscCall(MatMPIAIJGetSeqAIJ(A, &Ad, &Ao, &cmap));
5256:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)A), &size));
5257:   if (size == 1) {
5258:     if (scall == MAT_INITIAL_MATRIX) {
5259:       PetscCall(PetscObjectReference((PetscObject)Ad));
5260:       *A_loc = Ad;
5261:     } else if (scall == MAT_REUSE_MATRIX) {
5262:       PetscCall(MatCopy(Ad, *A_loc, SAME_NONZERO_PATTERN));
5263:     }
5264:     if (glob) PetscCall(ISCreateStride(PetscObjectComm((PetscObject)Ad), Ad->cmap->n, Ad->cmap->rstart, 1, glob));
5265:     PetscFunctionReturn(PETSC_SUCCESS);
5266:   }
5267:   PetscCall(PetscObjectQueryFunction((PetscObject)A, "MatMPIAIJGetLocalMatMerge_C", &f));
5268:   PetscCall(PetscLogEventBegin(MAT_Getlocalmat, A, 0, 0, 0));
5269:   if (f) {
5270:     PetscCall((*f)(A, scall, glob, A_loc));
5271:   } else {
5272:     Mat_SeqAIJ        *a = (Mat_SeqAIJ *)Ad->data;
5273:     Mat_SeqAIJ        *b = (Mat_SeqAIJ *)Ao->data;
5274:     Mat_SeqAIJ        *c;
5275:     PetscInt          *ai = a->i, *aj = a->j;
5276:     PetscInt          *bi = b->i, *bj = b->j;
5277:     PetscInt          *ci, *cj;
5278:     const PetscScalar *aa, *ba;
5279:     PetscScalar       *ca;
5280:     PetscInt           i, j, am, dn, on;

5282:     PetscCall(MatGetLocalSize(Ad, &am, &dn));
5283:     PetscCall(MatGetLocalSize(Ao, NULL, &on));
5284:     PetscCall(MatSeqAIJGetArrayRead(Ad, &aa));
5285:     PetscCall(MatSeqAIJGetArrayRead(Ao, &ba));
5286:     if (scall == MAT_INITIAL_MATRIX) {
5287:       PetscInt k;
5288:       PetscCall(PetscMalloc1(1 + am, &ci));
5289:       PetscCall(PetscMalloc1(ai[am] + bi[am], &cj));
5290:       PetscCall(PetscMalloc1(ai[am] + bi[am], &ca));
5291:       ci[0] = 0;
5292:       for (i = 0, k = 0; i < am; i++) {
5293:         const PetscInt ncols_o = bi[i + 1] - bi[i];
5294:         const PetscInt ncols_d = ai[i + 1] - ai[i];
5295:         ci[i + 1]              = ci[i] + ncols_o + ncols_d;
5296:         /* diagonal portion of A */
5297:         for (j = 0; j < ncols_d; j++, k++) {
5298:           cj[k] = *aj++;
5299:           ca[k] = *aa++;
5300:         }
5301:         /* off-diagonal portion of A */
5302:         for (j = 0; j < ncols_o; j++, k++) {
5303:           cj[k] = dn + *bj++;
5304:           ca[k] = *ba++;
5305:         }
5306:       }
5307:       /* put together the new matrix */
5308:       PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, am, dn + on, ci, cj, ca, A_loc));
5309:       /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5310:       /* Since these are PETSc arrays, change flags to free them as necessary. */
5311:       c          = (Mat_SeqAIJ *)(*A_loc)->data;
5312:       c->free_a  = PETSC_TRUE;
5313:       c->free_ij = PETSC_TRUE;
5314:       c->nonew   = 0;
5315:       PetscCall(MatSetType(*A_loc, ((PetscObject)Ad)->type_name));
5316:     } else if (scall == MAT_REUSE_MATRIX) {
5317:       PetscCall(MatSeqAIJGetArrayWrite(*A_loc, &ca));
5318:       for (i = 0; i < am; i++) {
5319:         const PetscInt ncols_d = ai[i + 1] - ai[i];
5320:         const PetscInt ncols_o = bi[i + 1] - bi[i];
5321:         /* diagonal portion of A */
5322:         for (j = 0; j < ncols_d; j++) *ca++ = *aa++;
5323:         /* off-diagonal portion of A */
5324:         for (j = 0; j < ncols_o; j++) *ca++ = *ba++;
5325:       }
5326:       PetscCall(MatSeqAIJRestoreArrayWrite(*A_loc, &ca));
5327:     } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid MatReuse %d", (int)scall);
5328:     PetscCall(MatSeqAIJRestoreArrayRead(Ad, &aa));
5329:     PetscCall(MatSeqAIJRestoreArrayRead(Ao, &aa));
5330:     if (glob) {
5331:       PetscInt cst, *gidx;

5333:       PetscCall(MatGetOwnershipRangeColumn(A, &cst, NULL));
5334:       PetscCall(PetscMalloc1(dn + on, &gidx));
5335:       for (i = 0; i < dn; i++) gidx[i] = cst + i;
5336:       for (i = 0; i < on; i++) gidx[i + dn] = cmap[i];
5337:       PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)Ad), dn + on, gidx, PETSC_OWN_POINTER, glob));
5338:     }
5339:   }
5340:   PetscCall(PetscLogEventEnd(MAT_Getlocalmat, A, 0, 0, 0));
5341:   PetscFunctionReturn(PETSC_SUCCESS);
5342: }

5344: /*@C
5345:   MatMPIAIJGetLocalMatCondensed - Creates a `MATSEQAIJ` matrix from an `MATMPIAIJ` matrix by taking all its local rows and NON-ZERO columns

5347:   Not Collective

5349:   Input Parameters:
5350: + A     - the matrix
5351: . scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`
5352: . row   - index set of rows to extract (or `NULL`)
5353: - col   - index set of columns to extract (or `NULL`)

5355:   Output Parameter:
5356: . A_loc - the local sequential matrix generated

5358:   Level: developer

5360: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMat()`
5361: @*/
5362: PetscErrorCode MatMPIAIJGetLocalMatCondensed(Mat A, MatReuse scall, IS *row, IS *col, Mat *A_loc)
5363: {
5364:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
5365:   PetscInt    i, start, end, ncols, nzA, nzB, *cmap, imark, *idx;
5366:   IS          isrowa, iscola;
5367:   Mat        *aloc;
5368:   PetscBool   match;

5370:   PetscFunctionBegin;
5371:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATMPIAIJ, &match));
5372:   PetscCheck(match, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Requires MATMPIAIJ matrix as input");
5373:   PetscCall(PetscLogEventBegin(MAT_Getlocalmatcondensed, A, 0, 0, 0));
5374:   if (!row) {
5375:     start = A->rmap->rstart;
5376:     end   = A->rmap->rend;
5377:     PetscCall(ISCreateStride(PETSC_COMM_SELF, end - start, start, 1, &isrowa));
5378:   } else {
5379:     isrowa = *row;
5380:   }
5381:   if (!col) {
5382:     start = A->cmap->rstart;
5383:     cmap  = a->garray;
5384:     nzA   = a->A->cmap->n;
5385:     nzB   = a->B->cmap->n;
5386:     PetscCall(PetscMalloc1(nzA + nzB, &idx));
5387:     ncols = 0;
5388:     for (i = 0; i < nzB; i++) {
5389:       if (cmap[i] < start) idx[ncols++] = cmap[i];
5390:       else break;
5391:     }
5392:     imark = i;
5393:     for (i = 0; i < nzA; i++) idx[ncols++] = start + i;
5394:     for (i = imark; i < nzB; i++) idx[ncols++] = cmap[i];
5395:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, &iscola));
5396:   } else {
5397:     iscola = *col;
5398:   }
5399:   if (scall != MAT_INITIAL_MATRIX) {
5400:     PetscCall(PetscMalloc1(1, &aloc));
5401:     aloc[0] = *A_loc;
5402:   }
5403:   PetscCall(MatCreateSubMatrices(A, 1, &isrowa, &iscola, scall, &aloc));
5404:   if (!col) { /* attach global id of condensed columns */
5405:     PetscCall(PetscObjectCompose((PetscObject)aloc[0], "_petsc_GetLocalMatCondensed_iscol", (PetscObject)iscola));
5406:   }
5407:   *A_loc = aloc[0];
5408:   PetscCall(PetscFree(aloc));
5409:   if (!row) PetscCall(ISDestroy(&isrowa));
5410:   if (!col) PetscCall(ISDestroy(&iscola));
5411:   PetscCall(PetscLogEventEnd(MAT_Getlocalmatcondensed, A, 0, 0, 0));
5412:   PetscFunctionReturn(PETSC_SUCCESS);
5413: }

5415: /*
5416:  * Create a sequential AIJ matrix based on row indices. a whole column is extracted once a row is matched.
5417:  * Row could be local or remote.The routine is designed to be scalable in memory so that nothing is based
5418:  * on a global size.
5419:  * */
5420: static PetscErrorCode MatCreateSeqSubMatrixWithRows_Private(Mat P, IS rows, Mat *P_oth)
5421: {
5422:   Mat_MPIAIJ            *p  = (Mat_MPIAIJ *)P->data;
5423:   Mat_SeqAIJ            *pd = (Mat_SeqAIJ *)p->A->data, *po = (Mat_SeqAIJ *)p->B->data, *p_oth;
5424:   PetscInt               plocalsize, nrows, *ilocal, *oilocal, i, lidx, *nrcols, *nlcols, ncol;
5425:   PetscMPIInt            owner;
5426:   PetscSFNode           *iremote, *oiremote;
5427:   const PetscInt        *lrowindices;
5428:   PetscSF                sf, osf;
5429:   PetscInt               pcstart, *roffsets, *loffsets, *pnnz, j;
5430:   PetscInt               ontotalcols, dntotalcols, ntotalcols, nout;
5431:   MPI_Comm               comm;
5432:   ISLocalToGlobalMapping mapping;
5433:   const PetscScalar     *pd_a, *po_a;

5435:   PetscFunctionBegin;
5436:   PetscCall(PetscObjectGetComm((PetscObject)P, &comm));
5437:   /* plocalsize is the number of roots
5438:    * nrows is the number of leaves
5439:    * */
5440:   PetscCall(MatGetLocalSize(P, &plocalsize, NULL));
5441:   PetscCall(ISGetLocalSize(rows, &nrows));
5442:   PetscCall(PetscCalloc1(nrows, &iremote));
5443:   PetscCall(ISGetIndices(rows, &lrowindices));
5444:   for (i = 0; i < nrows; i++) {
5445:     /* Find a remote index and an owner for a row
5446:      * The row could be local or remote
5447:      * */
5448:     owner = 0;
5449:     lidx  = 0;
5450:     PetscCall(PetscLayoutFindOwnerIndex(P->rmap, lrowindices[i], &owner, &lidx));
5451:     iremote[i].index = lidx;
5452:     iremote[i].rank  = owner;
5453:   }
5454:   /* Create SF to communicate how many nonzero columns for each row */
5455:   PetscCall(PetscSFCreate(comm, &sf));
5456:   /* SF will figure out the number of nonzero columns for each row, and their
5457:    * offsets
5458:    * */
5459:   PetscCall(PetscSFSetGraph(sf, plocalsize, nrows, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
5460:   PetscCall(PetscSFSetFromOptions(sf));
5461:   PetscCall(PetscSFSetUp(sf));

5463:   PetscCall(PetscCalloc1(2 * (plocalsize + 1), &roffsets));
5464:   PetscCall(PetscCalloc1(2 * plocalsize, &nrcols));
5465:   PetscCall(PetscCalloc1(nrows, &pnnz));
5466:   roffsets[0] = 0;
5467:   roffsets[1] = 0;
5468:   for (i = 0; i < plocalsize; i++) {
5469:     /* diagonal */
5470:     nrcols[i * 2 + 0] = pd->i[i + 1] - pd->i[i];
5471:     /* off-diagonal */
5472:     nrcols[i * 2 + 1] = po->i[i + 1] - po->i[i];
5473:     /* compute offsets so that we relative location for each row */
5474:     roffsets[(i + 1) * 2 + 0] = roffsets[i * 2 + 0] + nrcols[i * 2 + 0];
5475:     roffsets[(i + 1) * 2 + 1] = roffsets[i * 2 + 1] + nrcols[i * 2 + 1];
5476:   }
5477:   PetscCall(PetscCalloc1(2 * nrows, &nlcols));
5478:   PetscCall(PetscCalloc1(2 * nrows, &loffsets));
5479:   /* 'r' means root, and 'l' means leaf */
5480:   PetscCall(PetscSFBcastBegin(sf, MPIU_2INT, nrcols, nlcols, MPI_REPLACE));
5481:   PetscCall(PetscSFBcastBegin(sf, MPIU_2INT, roffsets, loffsets, MPI_REPLACE));
5482:   PetscCall(PetscSFBcastEnd(sf, MPIU_2INT, nrcols, nlcols, MPI_REPLACE));
5483:   PetscCall(PetscSFBcastEnd(sf, MPIU_2INT, roffsets, loffsets, MPI_REPLACE));
5484:   PetscCall(PetscSFDestroy(&sf));
5485:   PetscCall(PetscFree(roffsets));
5486:   PetscCall(PetscFree(nrcols));
5487:   dntotalcols = 0;
5488:   ontotalcols = 0;
5489:   ncol        = 0;
5490:   for (i = 0; i < nrows; i++) {
5491:     pnnz[i] = nlcols[i * 2 + 0] + nlcols[i * 2 + 1];
5492:     ncol    = PetscMax(pnnz[i], ncol);
5493:     /* diagonal */
5494:     dntotalcols += nlcols[i * 2 + 0];
5495:     /* off-diagonal */
5496:     ontotalcols += nlcols[i * 2 + 1];
5497:   }
5498:   /* We do not need to figure the right number of columns
5499:    * since all the calculations will be done by going through the raw data
5500:    * */
5501:   PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, nrows, ncol, 0, pnnz, P_oth));
5502:   PetscCall(MatSetUp(*P_oth));
5503:   PetscCall(PetscFree(pnnz));
5504:   p_oth = (Mat_SeqAIJ *)(*P_oth)->data;
5505:   /* diagonal */
5506:   PetscCall(PetscCalloc1(dntotalcols, &iremote));
5507:   /* off-diagonal */
5508:   PetscCall(PetscCalloc1(ontotalcols, &oiremote));
5509:   /* diagonal */
5510:   PetscCall(PetscCalloc1(dntotalcols, &ilocal));
5511:   /* off-diagonal */
5512:   PetscCall(PetscCalloc1(ontotalcols, &oilocal));
5513:   dntotalcols = 0;
5514:   ontotalcols = 0;
5515:   ntotalcols  = 0;
5516:   for (i = 0; i < nrows; i++) {
5517:     owner = 0;
5518:     PetscCall(PetscLayoutFindOwnerIndex(P->rmap, lrowindices[i], &owner, NULL));
5519:     /* Set iremote for diag matrix */
5520:     for (j = 0; j < nlcols[i * 2 + 0]; j++) {
5521:       iremote[dntotalcols].index = loffsets[i * 2 + 0] + j;
5522:       iremote[dntotalcols].rank  = owner;
5523:       /* P_oth is seqAIJ so that ilocal need to point to the first part of memory */
5524:       ilocal[dntotalcols++] = ntotalcols++;
5525:     }
5526:     /* off-diagonal */
5527:     for (j = 0; j < nlcols[i * 2 + 1]; j++) {
5528:       oiremote[ontotalcols].index = loffsets[i * 2 + 1] + j;
5529:       oiremote[ontotalcols].rank  = owner;
5530:       oilocal[ontotalcols++]      = ntotalcols++;
5531:     }
5532:   }
5533:   PetscCall(ISRestoreIndices(rows, &lrowindices));
5534:   PetscCall(PetscFree(loffsets));
5535:   PetscCall(PetscFree(nlcols));
5536:   PetscCall(PetscSFCreate(comm, &sf));
5537:   /* P serves as roots and P_oth is leaves
5538:    * Diag matrix
5539:    * */
5540:   PetscCall(PetscSFSetGraph(sf, pd->i[plocalsize], dntotalcols, ilocal, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
5541:   PetscCall(PetscSFSetFromOptions(sf));
5542:   PetscCall(PetscSFSetUp(sf));

5544:   PetscCall(PetscSFCreate(comm, &osf));
5545:   /* off-diagonal */
5546:   PetscCall(PetscSFSetGraph(osf, po->i[plocalsize], ontotalcols, oilocal, PETSC_OWN_POINTER, oiremote, PETSC_OWN_POINTER));
5547:   PetscCall(PetscSFSetFromOptions(osf));
5548:   PetscCall(PetscSFSetUp(osf));
5549:   PetscCall(MatSeqAIJGetArrayRead(p->A, &pd_a));
5550:   PetscCall(MatSeqAIJGetArrayRead(p->B, &po_a));
5551:   /* operate on the matrix internal data to save memory */
5552:   PetscCall(PetscSFBcastBegin(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5553:   PetscCall(PetscSFBcastBegin(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5554:   PetscCall(MatGetOwnershipRangeColumn(P, &pcstart, NULL));
5555:   /* Convert to global indices for diag matrix */
5556:   for (i = 0; i < pd->i[plocalsize]; i++) pd->j[i] += pcstart;
5557:   PetscCall(PetscSFBcastBegin(sf, MPIU_INT, pd->j, p_oth->j, MPI_REPLACE));
5558:   /* We want P_oth store global indices */
5559:   PetscCall(ISLocalToGlobalMappingCreate(comm, 1, p->B->cmap->n, p->garray, PETSC_COPY_VALUES, &mapping));
5560:   /* Use memory scalable approach */
5561:   PetscCall(ISLocalToGlobalMappingSetType(mapping, ISLOCALTOGLOBALMAPPINGHASH));
5562:   PetscCall(ISLocalToGlobalMappingApply(mapping, po->i[plocalsize], po->j, po->j));
5563:   PetscCall(PetscSFBcastBegin(osf, MPIU_INT, po->j, p_oth->j, MPI_REPLACE));
5564:   PetscCall(PetscSFBcastEnd(sf, MPIU_INT, pd->j, p_oth->j, MPI_REPLACE));
5565:   /* Convert back to local indices */
5566:   for (i = 0; i < pd->i[plocalsize]; i++) pd->j[i] -= pcstart;
5567:   PetscCall(PetscSFBcastEnd(osf, MPIU_INT, po->j, p_oth->j, MPI_REPLACE));
5568:   nout = 0;
5569:   PetscCall(ISGlobalToLocalMappingApply(mapping, IS_GTOLM_DROP, po->i[plocalsize], po->j, &nout, po->j));
5570:   PetscCheck(nout == po->i[plocalsize], comm, PETSC_ERR_ARG_INCOMP, "n %" PetscInt_FMT " does not equal to nout %" PetscInt_FMT " ", po->i[plocalsize], nout);
5571:   PetscCall(ISLocalToGlobalMappingDestroy(&mapping));
5572:   /* Exchange values */
5573:   PetscCall(PetscSFBcastEnd(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5574:   PetscCall(PetscSFBcastEnd(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5575:   PetscCall(MatSeqAIJRestoreArrayRead(p->A, &pd_a));
5576:   PetscCall(MatSeqAIJRestoreArrayRead(p->B, &po_a));
5577:   /* Stop PETSc from shrinking memory */
5578:   for (i = 0; i < nrows; i++) p_oth->ilen[i] = p_oth->imax[i];
5579:   PetscCall(MatAssemblyBegin(*P_oth, MAT_FINAL_ASSEMBLY));
5580:   PetscCall(MatAssemblyEnd(*P_oth, MAT_FINAL_ASSEMBLY));
5581:   /* Attach PetscSF objects to P_oth so that we can reuse it later */
5582:   PetscCall(PetscObjectCompose((PetscObject)*P_oth, "diagsf", (PetscObject)sf));
5583:   PetscCall(PetscObjectCompose((PetscObject)*P_oth, "offdiagsf", (PetscObject)osf));
5584:   PetscCall(PetscSFDestroy(&sf));
5585:   PetscCall(PetscSFDestroy(&osf));
5586:   PetscFunctionReturn(PETSC_SUCCESS);
5587: }

5589: /*
5590:  * Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns of local A
5591:  * This supports MPIAIJ and MAIJ
5592:  * */
5593: PetscErrorCode MatGetBrowsOfAcols_MPIXAIJ(Mat A, Mat P, PetscInt dof, MatReuse reuse, Mat *P_oth)
5594: {
5595:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data, *p = (Mat_MPIAIJ *)P->data;
5596:   Mat_SeqAIJ *p_oth;
5597:   IS          rows, map;
5598:   PetscHMapI  hamp;
5599:   PetscInt    i, htsize, *rowindices, off, *mapping, key, count;
5600:   MPI_Comm    comm;
5601:   PetscSF     sf, osf;
5602:   PetscBool   has;

5604:   PetscFunctionBegin;
5605:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
5606:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAocols, A, P, 0, 0));
5607:   /* If it is the first time, create an index set of off-diag nonzero columns of A,
5608:    *  and then create a submatrix (that often is an overlapping matrix)
5609:    * */
5610:   if (reuse == MAT_INITIAL_MATRIX) {
5611:     /* Use a hash table to figure out unique keys */
5612:     PetscCall(PetscHMapICreateWithSize(a->B->cmap->n, &hamp));
5613:     PetscCall(PetscCalloc1(a->B->cmap->n, &mapping));
5614:     count = 0;
5615:     /* Assume that  a->g is sorted, otherwise the following does not make sense */
5616:     for (i = 0; i < a->B->cmap->n; i++) {
5617:       key = a->garray[i] / dof;
5618:       PetscCall(PetscHMapIHas(hamp, key, &has));
5619:       if (!has) {
5620:         mapping[i] = count;
5621:         PetscCall(PetscHMapISet(hamp, key, count++));
5622:       } else {
5623:         /* Current 'i' has the same value the previous step */
5624:         mapping[i] = count - 1;
5625:       }
5626:     }
5627:     PetscCall(ISCreateGeneral(comm, a->B->cmap->n, mapping, PETSC_OWN_POINTER, &map));
5628:     PetscCall(PetscHMapIGetSize(hamp, &htsize));
5629:     PetscCheck(htsize == count, comm, PETSC_ERR_ARG_INCOMP, " Size of hash map %" PetscInt_FMT " is inconsistent with count %" PetscInt_FMT, htsize, count);
5630:     PetscCall(PetscCalloc1(htsize, &rowindices));
5631:     off = 0;
5632:     PetscCall(PetscHMapIGetKeys(hamp, &off, rowindices));
5633:     PetscCall(PetscHMapIDestroy(&hamp));
5634:     PetscCall(PetscSortInt(htsize, rowindices));
5635:     PetscCall(ISCreateGeneral(comm, htsize, rowindices, PETSC_OWN_POINTER, &rows));
5636:     /* In case, the matrix was already created but users want to recreate the matrix */
5637:     PetscCall(MatDestroy(P_oth));
5638:     PetscCall(MatCreateSeqSubMatrixWithRows_Private(P, rows, P_oth));
5639:     PetscCall(PetscObjectCompose((PetscObject)*P_oth, "aoffdiagtopothmapping", (PetscObject)map));
5640:     PetscCall(ISDestroy(&map));
5641:     PetscCall(ISDestroy(&rows));
5642:   } else if (reuse == MAT_REUSE_MATRIX) {
5643:     /* If matrix was already created, we simply update values using SF objects
5644:      * that as attached to the matrix earlier.
5645:      */
5646:     const PetscScalar *pd_a, *po_a;

5648:     PetscCall(PetscObjectQuery((PetscObject)*P_oth, "diagsf", (PetscObject *)&sf));
5649:     PetscCall(PetscObjectQuery((PetscObject)*P_oth, "offdiagsf", (PetscObject *)&osf));
5650:     PetscCheck(sf && osf, comm, PETSC_ERR_ARG_NULL, "Matrix is not initialized yet");
5651:     p_oth = (Mat_SeqAIJ *)(*P_oth)->data;
5652:     /* Update values in place */
5653:     PetscCall(MatSeqAIJGetArrayRead(p->A, &pd_a));
5654:     PetscCall(MatSeqAIJGetArrayRead(p->B, &po_a));
5655:     PetscCall(PetscSFBcastBegin(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5656:     PetscCall(PetscSFBcastBegin(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5657:     PetscCall(PetscSFBcastEnd(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5658:     PetscCall(PetscSFBcastEnd(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5659:     PetscCall(MatSeqAIJRestoreArrayRead(p->A, &pd_a));
5660:     PetscCall(MatSeqAIJRestoreArrayRead(p->B, &po_a));
5661:   } else SETERRQ(comm, PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown reuse type");
5662:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAocols, A, P, 0, 0));
5663:   PetscFunctionReturn(PETSC_SUCCESS);
5664: }

5666: /*@C
5667:   MatGetBrowsOfAcols - Returns `IS` that contain rows of `B` that equal to nonzero columns of local `A`

5669:   Collective

5671:   Input Parameters:
5672: + A     - the first matrix in `MATMPIAIJ` format
5673: . B     - the second matrix in `MATMPIAIJ` format
5674: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5676:   Output Parameters:
5677: + rowb  - On input index sets of rows of B to extract (or `NULL`), modified on output
5678: . colb  - On input index sets of columns of B to extract (or `NULL`), modified on output
5679: - B_seq - the sequential matrix generated

5681:   Level: developer

5683: .seealso: `Mat`, `MATMPIAIJ`, `IS`, `MatReuse`
5684: @*/
5685: PetscErrorCode MatGetBrowsOfAcols(Mat A, Mat B, MatReuse scall, IS *rowb, IS *colb, Mat *B_seq)
5686: {
5687:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
5688:   PetscInt   *idx, i, start, ncols, nzA, nzB, *cmap, imark;
5689:   IS          isrowb, iscolb;
5690:   Mat        *bseq = NULL;

5692:   PetscFunctionBegin;
5693:   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 ")",
5694:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
5695:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAcols, A, B, 0, 0));

5697:   if (scall == MAT_INITIAL_MATRIX) {
5698:     start = A->cmap->rstart;
5699:     cmap  = a->garray;
5700:     nzA   = a->A->cmap->n;
5701:     nzB   = a->B->cmap->n;
5702:     PetscCall(PetscMalloc1(nzA + nzB, &idx));
5703:     ncols = 0;
5704:     for (i = 0; i < nzB; i++) { /* row < local row index */
5705:       if (cmap[i] < start) idx[ncols++] = cmap[i];
5706:       else break;
5707:     }
5708:     imark = i;
5709:     for (i = 0; i < nzA; i++) idx[ncols++] = start + i;   /* local rows */
5710:     for (i = imark; i < nzB; i++) idx[ncols++] = cmap[i]; /* row > local row index */
5711:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, &isrowb));
5712:     PetscCall(ISCreateStride(PETSC_COMM_SELF, B->cmap->N, 0, 1, &iscolb));
5713:   } else {
5714:     PetscCheck(rowb && colb, PETSC_COMM_SELF, PETSC_ERR_SUP, "IS rowb and colb must be provided for MAT_REUSE_MATRIX");
5715:     isrowb = *rowb;
5716:     iscolb = *colb;
5717:     PetscCall(PetscMalloc1(1, &bseq));
5718:     bseq[0] = *B_seq;
5719:   }
5720:   PetscCall(MatCreateSubMatrices(B, 1, &isrowb, &iscolb, scall, &bseq));
5721:   *B_seq = bseq[0];
5722:   PetscCall(PetscFree(bseq));
5723:   if (!rowb) {
5724:     PetscCall(ISDestroy(&isrowb));
5725:   } else {
5726:     *rowb = isrowb;
5727:   }
5728:   if (!colb) {
5729:     PetscCall(ISDestroy(&iscolb));
5730:   } else {
5731:     *colb = iscolb;
5732:   }
5733:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAcols, A, B, 0, 0));
5734:   PetscFunctionReturn(PETSC_SUCCESS);
5735: }

5737: /*
5738:     MatGetBrowsOfAoCols_MPIAIJ - Creates a `MATSEQAIJ` matrix by taking rows of B that equal to nonzero columns
5739:     of the OFF-DIAGONAL portion of local A

5741:     Collective

5743:    Input Parameters:
5744: +    A,B - the matrices in `MATMPIAIJ` format
5745: -    scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5747:    Output Parameter:
5748: +    startsj_s - starting point in B's sending j-arrays, saved for MAT_REUSE (or NULL)
5749: .    startsj_r - starting point in B's receiving j-arrays, saved for MAT_REUSE (or NULL)
5750: .    bufa_ptr - array for sending matrix values, saved for MAT_REUSE (or NULL)
5751: -    B_oth - the sequential matrix generated with size aBn=a->B->cmap->n by B->cmap->N

5753:     Developer Note:
5754:     This directly accesses information inside the VecScatter associated with the matrix-vector product
5755:      for this matrix. This is not desirable..

5757:     Level: developer

5759: */

5761: PetscErrorCode MatGetBrowsOfAoCols_MPIAIJ(Mat A, Mat B, MatReuse scall, PetscInt **startsj_s, PetscInt **startsj_r, MatScalar **bufa_ptr, Mat *B_oth)
5762: {
5763:   Mat_MPIAIJ        *a = (Mat_MPIAIJ *)A->data;
5764:   VecScatter         ctx;
5765:   MPI_Comm           comm;
5766:   const PetscMPIInt *rprocs, *sprocs;
5767:   PetscMPIInt        nrecvs, nsends;
5768:   const PetscInt    *srow, *rstarts, *sstarts;
5769:   PetscInt          *rowlen, *bufj, *bufJ, ncols = 0, aBn = a->B->cmap->n, row, *b_othi, *b_othj, *rvalues = NULL, *svalues = NULL, *cols, sbs, rbs;
5770:   PetscInt           i, j, k = 0, l, ll, nrows, *rstartsj = NULL, *sstartsj, len;
5771:   PetscScalar       *b_otha, *bufa, *bufA, *vals = NULL;
5772:   MPI_Request       *reqs = NULL, *rwaits = NULL, *swaits = NULL;
5773:   PetscMPIInt        size, tag, rank, nreqs;

5775:   PetscFunctionBegin;
5776:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
5777:   PetscCallMPI(MPI_Comm_size(comm, &size));

5779:   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 ")",
5780:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
5781:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAocols, A, B, 0, 0));
5782:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

5784:   if (size == 1) {
5785:     startsj_s = NULL;
5786:     bufa_ptr  = NULL;
5787:     *B_oth    = NULL;
5788:     PetscFunctionReturn(PETSC_SUCCESS);
5789:   }

5791:   ctx = a->Mvctx;
5792:   tag = ((PetscObject)ctx)->tag;

5794:   PetscCall(VecScatterGetRemote_Private(ctx, PETSC_TRUE /*send*/, &nsends, &sstarts, &srow, &sprocs, &sbs));
5795:   /* rprocs[] must be ordered so that indices received from them are ordered in rvalues[], which is key to algorithms used in this subroutine */
5796:   PetscCall(VecScatterGetRemoteOrdered_Private(ctx, PETSC_FALSE /*recv*/, &nrecvs, &rstarts, NULL /*indices not needed*/, &rprocs, &rbs));
5797:   PetscCall(PetscMPIIntCast(nsends + nrecvs, &nreqs));
5798:   PetscCall(PetscMalloc1(nreqs, &reqs));
5799:   rwaits = reqs;
5800:   swaits = PetscSafePointerPlusOffset(reqs, nrecvs);

5802:   if (!startsj_s || !bufa_ptr) scall = MAT_INITIAL_MATRIX;
5803:   if (scall == MAT_INITIAL_MATRIX) {
5804:     /* i-array */
5805:     /*  post receives */
5806:     if (nrecvs) PetscCall(PetscMalloc1(rbs * (rstarts[nrecvs] - rstarts[0]), &rvalues)); /* rstarts can be NULL when nrecvs=0 */
5807:     for (i = 0; i < nrecvs; i++) {
5808:       rowlen = rvalues + rstarts[i] * rbs;
5809:       nrows  = (rstarts[i + 1] - rstarts[i]) * rbs; /* num of indices to be received */
5810:       PetscCallMPI(MPIU_Irecv(rowlen, nrows, MPIU_INT, rprocs[i], tag, comm, rwaits + i));
5811:     }

5813:     /* pack the outgoing message */
5814:     PetscCall(PetscMalloc2(nsends + 1, &sstartsj, nrecvs + 1, &rstartsj));

5816:     sstartsj[0] = 0;
5817:     rstartsj[0] = 0;
5818:     len         = 0; /* total length of j or a array to be sent */
5819:     if (nsends) {
5820:       k = sstarts[0]; /* ATTENTION: sstarts[0] and rstarts[0] are not necessarily zero */
5821:       PetscCall(PetscMalloc1(sbs * (sstarts[nsends] - sstarts[0]), &svalues));
5822:     }
5823:     for (i = 0; i < nsends; i++) {
5824:       rowlen = svalues + (sstarts[i] - sstarts[0]) * sbs;
5825:       nrows  = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5826:       for (j = 0; j < nrows; j++) {
5827:         row = srow[k] + B->rmap->range[rank]; /* global row idx */
5828:         for (l = 0; l < sbs; l++) {
5829:           PetscCall(MatGetRow_MPIAIJ(B, row + l, &ncols, NULL, NULL)); /* rowlength */

5831:           rowlen[j * sbs + l] = ncols;

5833:           len += ncols;
5834:           PetscCall(MatRestoreRow_MPIAIJ(B, row + l, &ncols, NULL, NULL));
5835:         }
5836:         k++;
5837:       }
5838:       PetscCallMPI(MPIU_Isend(rowlen, nrows * sbs, MPIU_INT, sprocs[i], tag, comm, swaits + i));

5840:       sstartsj[i + 1] = len; /* starting point of (i+1)-th outgoing msg in bufj and bufa */
5841:     }
5842:     /* recvs and sends of i-array are completed */
5843:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5844:     PetscCall(PetscFree(svalues));

5846:     /* allocate buffers for sending j and a arrays */
5847:     PetscCall(PetscMalloc1(len, &bufj));
5848:     PetscCall(PetscMalloc1(len, &bufa));

5850:     /* create i-array of B_oth */
5851:     PetscCall(PetscMalloc1(aBn + 1, &b_othi));

5853:     b_othi[0] = 0;
5854:     len       = 0; /* total length of j or a array to be received */
5855:     k         = 0;
5856:     for (i = 0; i < nrecvs; i++) {
5857:       rowlen = rvalues + (rstarts[i] - rstarts[0]) * rbs;
5858:       nrows  = (rstarts[i + 1] - rstarts[i]) * rbs; /* num of rows to be received */
5859:       for (j = 0; j < nrows; j++) {
5860:         b_othi[k + 1] = b_othi[k] + rowlen[j];
5861:         PetscCall(PetscIntSumError(rowlen[j], len, &len));
5862:         k++;
5863:       }
5864:       rstartsj[i + 1] = len; /* starting point of (i+1)-th incoming msg in bufj and bufa */
5865:     }
5866:     PetscCall(PetscFree(rvalues));

5868:     /* allocate space for j and a arrays of B_oth */
5869:     PetscCall(PetscMalloc1(b_othi[aBn], &b_othj));
5870:     PetscCall(PetscMalloc1(b_othi[aBn], &b_otha));

5872:     /* j-array */
5873:     /*  post receives of j-array */
5874:     for (i = 0; i < nrecvs; i++) {
5875:       nrows = rstartsj[i + 1] - rstartsj[i]; /* length of the msg received */
5876:       PetscCallMPI(MPIU_Irecv(PetscSafePointerPlusOffset(b_othj, rstartsj[i]), nrows, MPIU_INT, rprocs[i], tag, comm, rwaits + i));
5877:     }

5879:     /* pack the outgoing message j-array */
5880:     if (nsends) k = sstarts[0];
5881:     for (i = 0; i < nsends; i++) {
5882:       nrows = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5883:       bufJ  = PetscSafePointerPlusOffset(bufj, sstartsj[i]);
5884:       for (j = 0; j < nrows; j++) {
5885:         row = srow[k++] + B->rmap->range[rank]; /* global row idx */
5886:         for (ll = 0; ll < sbs; ll++) {
5887:           PetscCall(MatGetRow_MPIAIJ(B, row + ll, &ncols, &cols, NULL));
5888:           for (l = 0; l < ncols; l++) *bufJ++ = cols[l];
5889:           PetscCall(MatRestoreRow_MPIAIJ(B, row + ll, &ncols, &cols, NULL));
5890:         }
5891:       }
5892:       PetscCallMPI(MPIU_Isend(PetscSafePointerPlusOffset(bufj, sstartsj[i]), sstartsj[i + 1] - sstartsj[i], MPIU_INT, sprocs[i], tag, comm, swaits + i));
5893:     }

5895:     /* recvs and sends of j-array are completed */
5896:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5897:   } else if (scall == MAT_REUSE_MATRIX) {
5898:     sstartsj = *startsj_s;
5899:     rstartsj = *startsj_r;
5900:     bufa     = *bufa_ptr;
5901:     PetscCall(MatSeqAIJGetArrayWrite(*B_oth, &b_otha));
5902:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Matrix P does not possess an object container");

5904:   /* a-array */
5905:   /*  post receives of a-array */
5906:   for (i = 0; i < nrecvs; i++) {
5907:     nrows = rstartsj[i + 1] - rstartsj[i]; /* length of the msg received */
5908:     PetscCallMPI(MPIU_Irecv(PetscSafePointerPlusOffset(b_otha, rstartsj[i]), nrows, MPIU_SCALAR, rprocs[i], tag, comm, rwaits + i));
5909:   }

5911:   /* pack the outgoing message a-array */
5912:   if (nsends) k = sstarts[0];
5913:   for (i = 0; i < nsends; i++) {
5914:     nrows = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5915:     bufA  = PetscSafePointerPlusOffset(bufa, sstartsj[i]);
5916:     for (j = 0; j < nrows; j++) {
5917:       row = srow[k++] + B->rmap->range[rank]; /* global row idx */
5918:       for (ll = 0; ll < sbs; ll++) {
5919:         PetscCall(MatGetRow_MPIAIJ(B, row + ll, &ncols, NULL, &vals));
5920:         for (l = 0; l < ncols; l++) *bufA++ = vals[l];
5921:         PetscCall(MatRestoreRow_MPIAIJ(B, row + ll, &ncols, NULL, &vals));
5922:       }
5923:     }
5924:     PetscCallMPI(MPIU_Isend(PetscSafePointerPlusOffset(bufa, sstartsj[i]), sstartsj[i + 1] - sstartsj[i], MPIU_SCALAR, sprocs[i], tag, comm, swaits + i));
5925:   }
5926:   /* recvs and sends of a-array are completed */
5927:   if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5928:   PetscCall(PetscFree(reqs));

5930:   if (scall == MAT_INITIAL_MATRIX) {
5931:     Mat_SeqAIJ *b_oth;

5933:     /* put together the new matrix */
5934:     PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, aBn, B->cmap->N, b_othi, b_othj, b_otha, B_oth));

5936:     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5937:     /* Since these are PETSc arrays, change flags to free them as necessary. */
5938:     b_oth          = (Mat_SeqAIJ *)(*B_oth)->data;
5939:     b_oth->free_a  = PETSC_TRUE;
5940:     b_oth->free_ij = PETSC_TRUE;
5941:     b_oth->nonew   = 0;

5943:     PetscCall(PetscFree(bufj));
5944:     if (!startsj_s || !bufa_ptr) {
5945:       PetscCall(PetscFree2(sstartsj, rstartsj));
5946:       PetscCall(PetscFree(bufa_ptr));
5947:     } else {
5948:       *startsj_s = sstartsj;
5949:       *startsj_r = rstartsj;
5950:       *bufa_ptr  = bufa;
5951:     }
5952:   } else if (scall == MAT_REUSE_MATRIX) {
5953:     PetscCall(MatSeqAIJRestoreArrayWrite(*B_oth, &b_otha));
5954:   }

5956:   PetscCall(VecScatterRestoreRemote_Private(ctx, PETSC_TRUE, &nsends, &sstarts, &srow, &sprocs, &sbs));
5957:   PetscCall(VecScatterRestoreRemoteOrdered_Private(ctx, PETSC_FALSE, &nrecvs, &rstarts, NULL, &rprocs, &rbs));
5958:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAocols, A, B, 0, 0));
5959:   PetscFunctionReturn(PETSC_SUCCESS);
5960: }

5962: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCRL(Mat, MatType, MatReuse, Mat *);
5963: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJPERM(Mat, MatType, MatReuse, Mat *);
5964: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJSELL(Mat, MatType, MatReuse, Mat *);
5965: #if defined(PETSC_HAVE_MKL_SPARSE)
5966: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJMKL(Mat, MatType, MatReuse, Mat *);
5967: #endif
5968: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIBAIJ(Mat, MatType, MatReuse, Mat *);
5969: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPISBAIJ(Mat, MatType, MatReuse, Mat *);
5970: #if defined(PETSC_HAVE_ELEMENTAL)
5971: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_Elemental(Mat, MatType, MatReuse, Mat *);
5972: #endif
5973: #if defined(PETSC_HAVE_SCALAPACK) && (defined(PETSC_USE_REAL_SINGLE) || defined(PETSC_USE_REAL_DOUBLE))
5974: PETSC_INTERN PetscErrorCode MatConvert_AIJ_ScaLAPACK(Mat, MatType, MatReuse, Mat *);
5975: #endif
5976: #if defined(PETSC_HAVE_HYPRE)
5977: PETSC_INTERN PetscErrorCode MatConvert_AIJ_HYPRE(Mat, MatType, MatReuse, Mat *);
5978: #endif
5979: #if defined(PETSC_HAVE_CUDA)
5980: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCUSPARSE(Mat, MatType, MatReuse, Mat *);
5981: #endif
5982: #if defined(PETSC_HAVE_HIP)
5983: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJHIPSPARSE(Mat, MatType, MatReuse, Mat *);
5984: #endif
5985: #if defined(PETSC_HAVE_KOKKOS_KERNELS)
5986: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJKokkos(Mat, MatType, MatReuse, Mat *);
5987: #endif
5988: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPISELL(Mat, MatType, MatReuse, Mat *);
5989: PETSC_INTERN PetscErrorCode MatConvert_XAIJ_IS(Mat, MatType, MatReuse, Mat *);
5990: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_IS_XAIJ(Mat);

5992: /*
5993:     Computes (B'*A')' since computing B*A directly is untenable

5995:                n                       p                          p
5996:         [             ]       [             ]         [                 ]
5997:       m [      A      ]  *  n [       B     ]   =   m [         C       ]
5998:         [             ]       [             ]         [                 ]

6000: */
6001: static PetscErrorCode MatMatMultNumeric_MPIDense_MPIAIJ(Mat A, Mat B, Mat C)
6002: {
6003:   Mat At, Bt, Ct;

6005:   PetscFunctionBegin;
6006:   PetscCall(MatTranspose(A, MAT_INITIAL_MATRIX, &At));
6007:   PetscCall(MatTranspose(B, MAT_INITIAL_MATRIX, &Bt));
6008:   PetscCall(MatMatMult(Bt, At, MAT_INITIAL_MATRIX, PETSC_CURRENT, &Ct));
6009:   PetscCall(MatDestroy(&At));
6010:   PetscCall(MatDestroy(&Bt));
6011:   PetscCall(MatTransposeSetPrecursor(Ct, C));
6012:   PetscCall(MatTranspose(Ct, MAT_REUSE_MATRIX, &C));
6013:   PetscCall(MatDestroy(&Ct));
6014:   PetscFunctionReturn(PETSC_SUCCESS);
6015: }

6017: static PetscErrorCode MatMatMultSymbolic_MPIDense_MPIAIJ(Mat A, Mat B, PetscReal fill, Mat C)
6018: {
6019:   PetscBool cisdense;

6021:   PetscFunctionBegin;
6022:   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);
6023:   PetscCall(MatSetSizes(C, A->rmap->n, B->cmap->n, A->rmap->N, B->cmap->N));
6024:   PetscCall(MatSetBlockSizesFromMats(C, A, B));
6025:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &cisdense, MATMPIDENSE, MATMPIDENSECUDA, MATMPIDENSEHIP, ""));
6026:   if (!cisdense) PetscCall(MatSetType(C, ((PetscObject)A)->type_name));
6027:   PetscCall(MatSetUp(C));

6029:   C->ops->matmultnumeric = MatMatMultNumeric_MPIDense_MPIAIJ;
6030:   PetscFunctionReturn(PETSC_SUCCESS);
6031: }

6033: static PetscErrorCode MatProductSetFromOptions_MPIDense_MPIAIJ_AB(Mat C)
6034: {
6035:   Mat_Product *product = C->product;
6036:   Mat          A = product->A, B = product->B;

6038:   PetscFunctionBegin;
6039:   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 ")",
6040:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
6041:   C->ops->matmultsymbolic = MatMatMultSymbolic_MPIDense_MPIAIJ;
6042:   C->ops->productsymbolic = MatProductSymbolic_AB;
6043:   PetscFunctionReturn(PETSC_SUCCESS);
6044: }

6046: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_MPIDense_MPIAIJ(Mat C)
6047: {
6048:   Mat_Product *product = C->product;

6050:   PetscFunctionBegin;
6051:   if (product->type == MATPRODUCT_AB) PetscCall(MatProductSetFromOptions_MPIDense_MPIAIJ_AB(C));
6052:   PetscFunctionReturn(PETSC_SUCCESS);
6053: }

6055: /*
6056:    Merge two sets of sorted nonzeros and return a CSR for the merged (sequential) matrix

6058:   Input Parameters:

6060:     j1,rowBegin1,rowEnd1,jmap1: describe the first set of nonzeros (Set1)
6061:     j2,rowBegin2,rowEnd2,jmap2: describe the second set of nonzeros (Set2)

6063:     mat: both sets' nonzeros are on m rows, where m is the number of local rows of the matrix mat

6065:     For Set1, j1[] contains column indices of the nonzeros.
6066:     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
6067:     respectively (note rowEnd1[k] is not necessarily equal to rwoBegin1[k+1]). Indices in this range of j1[] are sorted,
6068:     but might have repeats. jmap1[t+1] - jmap1[t] is the number of repeats for the t-th unique nonzero in Set1.

6070:     Similar for Set2.

6072:     This routine merges the two sets of nonzeros row by row and removes repeats.

6074:   Output Parameters: (memory is allocated by the caller)

6076:     i[],j[]: the CSR of the merged matrix, which has m rows.
6077:     imap1[]: the k-th unique nonzero in Set1 (k=0,1,...) corresponds to imap1[k]-th unique nonzero in the merged matrix.
6078:     imap2[]: similar to imap1[], but for Set2.
6079:     Note we order nonzeros row-by-row and from left to right.
6080: */
6081: 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[])
6082: {
6083:   PetscInt   r, m; /* Row index of mat */
6084:   PetscCount t, t1, t2, b1, e1, b2, e2;

6086:   PetscFunctionBegin;
6087:   PetscCall(MatGetLocalSize(mat, &m, NULL));
6088:   t1 = t2 = t = 0; /* Count unique nonzeros of in Set1, Set1 and the merged respectively */
6089:   i[0]        = 0;
6090:   for (r = 0; r < m; r++) { /* Do row by row merging */
6091:     b1 = rowBegin1[r];
6092:     e1 = rowEnd1[r];
6093:     b2 = rowBegin2[r];
6094:     e2 = rowEnd2[r];
6095:     while (b1 < e1 && b2 < e2) {
6096:       if (j1[b1] == j2[b2]) { /* Same column index and hence same nonzero */
6097:         j[t]      = j1[b1];
6098:         imap1[t1] = t;
6099:         imap2[t2] = t;
6100:         b1 += jmap1[t1 + 1] - jmap1[t1]; /* Jump to next unique local nonzero */
6101:         b2 += jmap2[t2 + 1] - jmap2[t2]; /* Jump to next unique remote nonzero */
6102:         t1++;
6103:         t2++;
6104:         t++;
6105:       } else if (j1[b1] < j2[b2]) {
6106:         j[t]      = j1[b1];
6107:         imap1[t1] = t;
6108:         b1 += jmap1[t1 + 1] - jmap1[t1];
6109:         t1++;
6110:         t++;
6111:       } else {
6112:         j[t]      = j2[b2];
6113:         imap2[t2] = t;
6114:         b2 += jmap2[t2 + 1] - jmap2[t2];
6115:         t2++;
6116:         t++;
6117:       }
6118:     }
6119:     /* Merge the remaining in either j1[] or j2[] */
6120:     while (b1 < e1) {
6121:       j[t]      = j1[b1];
6122:       imap1[t1] = t;
6123:       b1 += jmap1[t1 + 1] - jmap1[t1];
6124:       t1++;
6125:       t++;
6126:     }
6127:     while (b2 < e2) {
6128:       j[t]      = j2[b2];
6129:       imap2[t2] = t;
6130:       b2 += jmap2[t2 + 1] - jmap2[t2];
6131:       t2++;
6132:       t++;
6133:     }
6134:     PetscCall(PetscIntCast(t, i + r + 1));
6135:   }
6136:   PetscFunctionReturn(PETSC_SUCCESS);
6137: }

6139: /*
6140:   Split nonzeros in a block of local rows into two subsets: those in the diagonal block and those in the off-diagonal block

6142:   Input Parameters:
6143:     mat: an MPI matrix that provides row and column layout information for splitting. Let's say its number of local rows is m.
6144:     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[]
6145:       respectively, along with a permutation array perm[]. Length of the i[],j[],perm[] arrays is n.

6147:       i[] is already sorted, but within a row, j[] is not sorted and might have repeats.
6148:       i[] might contain negative indices at the beginning, which means the corresponding entries should be ignored in the splitting.

6150:   Output Parameters:
6151:     j[],perm[]: the routine needs to sort j[] within each row along with perm[].
6152:     rowBegin[],rowMid[],rowEnd[]: of length m, and the memory is preallocated and zeroed by the caller.
6153:       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,
6154:       and [rowMid[r],rowEnd[r]) point to begin/end entries of row r of the off-diagonal block.

6156:     Aperm[],Ajmap[],Atot,Annz: Arrays are allocated by this routine.
6157:       Atot: number of entries belonging to the diagonal block.
6158:       Annz: number of unique nonzeros belonging to the diagonal block.
6159:       Aperm[Atot] stores values from perm[] for entries belonging to the diagonal block. Length of Aperm[] is Atot, though it may also count
6160:         repeats (i.e., same 'i,j' pair).
6161:       Ajmap[Annz+1] stores the number of repeats of each unique entry belonging to the diagonal block. More precisely, Ajmap[t+1] - Ajmap[t]
6162:         is the number of repeats for the t-th unique entry in the diagonal block. Ajmap[0] is always 0.

6164:       Atot: number of entries belonging to the diagonal block
6165:       Annz: number of unique nonzeros belonging to the diagonal block.

6167:     Bperm[], Bjmap[], Btot, Bnnz are similar but for the off-diagonal block.

6169:     Aperm[],Bperm[],Ajmap[] and Bjmap[] are allocated separately by this routine with PetscMalloc1().
6170: */
6171: 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_)
6172: {
6173:   PetscInt    cstart, cend, rstart, rend, row, col;
6174:   PetscCount  Atot = 0, Btot = 0; /* Total number of nonzeros in the diagonal and off-diagonal blocks */
6175:   PetscCount  Annz = 0, Bnnz = 0; /* Number of unique nonzeros in the diagonal and off-diagonal blocks */
6176:   PetscCount  k, m, p, q, r, s, mid;
6177:   PetscCount *Aperm, *Bperm, *Ajmap, *Bjmap;

6179:   PetscFunctionBegin;
6180:   PetscCall(PetscLayoutGetRange(mat->rmap, &rstart, &rend));
6181:   PetscCall(PetscLayoutGetRange(mat->cmap, &cstart, &cend));
6182:   m = rend - rstart;

6184:   /* Skip negative rows */
6185:   for (k = 0; k < n; k++)
6186:     if (i[k] >= 0) break;

6188:   /* Process [k,n): sort and partition each local row into diag and offdiag portions,
6189:      fill rowBegin[], rowMid[], rowEnd[], and count Atot, Btot, Annz, Bnnz.
6190:   */
6191:   while (k < n) {
6192:     row = i[k];
6193:     /* Entries in [k,s) are in one row. Shift diagonal block col indices so that diag is ahead of offdiag after sorting the row */
6194:     for (s = k; s < n; s++)
6195:       if (i[s] != row) break;

6197:     /* Shift diag columns to range of [-PETSC_INT_MAX, -1] */
6198:     for (p = k; p < s; p++) {
6199:       if (j[p] >= cstart && j[p] < cend) j[p] -= PETSC_INT_MAX;
6200:     }
6201:     PetscCall(PetscSortIntWithCountArray(s - k, j + k, perm + k));
6202:     PetscCall(PetscSortedIntUpperBound(j, k, s, -1, &mid)); /* Separate [k,s) into [k,mid) for diag and [mid,s) for offdiag */
6203:     rowBegin[row - rstart] = k;
6204:     rowMid[row - rstart]   = mid;
6205:     rowEnd[row - rstart]   = s;
6206:     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);

6208:     /* Count nonzeros of this diag/offdiag row, which might have repeats */
6209:     Atot += mid - k;
6210:     Btot += s - mid;

6212:     /* Count unique nonzeros of this diag row */
6213:     for (p = k; p < mid;) {
6214:       col = j[p];
6215:       do {
6216:         j[p] += PETSC_INT_MAX; /* Revert the modified diagonal indices */
6217:         p++;
6218:       } while (p < mid && j[p] == col);
6219:       Annz++;
6220:     }

6222:     /* Count unique nonzeros of this offdiag row */
6223:     for (p = mid; p < s;) {
6224:       col = j[p];
6225:       do {
6226:         p++;
6227:       } while (p < s && j[p] == col);
6228:       Bnnz++;
6229:     }
6230:     k = s;
6231:   }

6233:   /* Allocation according to Atot, Btot, Annz, Bnnz */
6234:   PetscCall(PetscMalloc1(Atot, &Aperm));
6235:   PetscCall(PetscMalloc1(Btot, &Bperm));
6236:   PetscCall(PetscMalloc1(Annz + 1, &Ajmap));
6237:   PetscCall(PetscMalloc1(Bnnz + 1, &Bjmap));

6239:   /* Re-scan indices and copy diag/offdiag permutation indices to Aperm, Bperm and also fill Ajmap and Bjmap */
6240:   Ajmap[0] = Bjmap[0] = Atot = Btot = Annz = Bnnz = 0;
6241:   for (r = 0; r < m; r++) {
6242:     k   = rowBegin[r];
6243:     mid = rowMid[r];
6244:     s   = rowEnd[r];
6245:     PetscCall(PetscArraycpy(PetscSafePointerPlusOffset(Aperm, Atot), PetscSafePointerPlusOffset(perm, k), mid - k));
6246:     PetscCall(PetscArraycpy(PetscSafePointerPlusOffset(Bperm, Btot), PetscSafePointerPlusOffset(perm, mid), s - mid));
6247:     Atot += mid - k;
6248:     Btot += s - mid;

6250:     /* Scan column indices in this row and find out how many repeats each unique nonzero has */
6251:     for (p = k; p < mid;) {
6252:       col = j[p];
6253:       q   = p;
6254:       do {
6255:         p++;
6256:       } while (p < mid && j[p] == col);
6257:       Ajmap[Annz + 1] = Ajmap[Annz] + (p - q);
6258:       Annz++;
6259:     }

6261:     for (p = mid; p < s;) {
6262:       col = j[p];
6263:       q   = p;
6264:       do {
6265:         p++;
6266:       } while (p < s && j[p] == col);
6267:       Bjmap[Bnnz + 1] = Bjmap[Bnnz] + (p - q);
6268:       Bnnz++;
6269:     }
6270:   }
6271:   /* Output */
6272:   *Aperm_ = Aperm;
6273:   *Annz_  = Annz;
6274:   *Atot_  = Atot;
6275:   *Ajmap_ = Ajmap;
6276:   *Bperm_ = Bperm;
6277:   *Bnnz_  = Bnnz;
6278:   *Btot_  = Btot;
6279:   *Bjmap_ = Bjmap;
6280:   PetscFunctionReturn(PETSC_SUCCESS);
6281: }

6283: /*
6284:   Expand the jmap[] array to make a new one in view of nonzeros in the merged matrix

6286:   Input Parameters:
6287:     nnz1: number of unique nonzeros in a set that was used to produce imap[], jmap[]
6288:     nnz:  number of unique nonzeros in the merged matrix
6289:     imap[nnz1]: i-th nonzero in the set is the imap[i]-th nonzero in the merged matrix
6290:     jmap[nnz1+1]: i-th nonzero in the set has jmap[i+1] - jmap[i] repeats in the set

6292:   Output Parameter: (memory is allocated by the caller)
6293:     jmap_new[nnz+1]: i-th nonzero in the merged matrix has jmap_new[i+1] - jmap_new[i] repeats in the set

6295:   Example:
6296:     nnz1 = 4
6297:     nnz  = 6
6298:     imap = [1,3,4,5]
6299:     jmap = [0,3,5,6,7]
6300:    then,
6301:     jmap_new = [0,0,3,3,5,6,7]
6302: */
6303: static PetscErrorCode ExpandJmap_Internal(PetscCount nnz1, PetscCount nnz, const PetscCount imap[], const PetscCount jmap[], PetscCount jmap_new[])
6304: {
6305:   PetscCount k, p;

6307:   PetscFunctionBegin;
6308:   jmap_new[0] = 0;
6309:   p           = nnz;                /* p loops over jmap_new[] backwards */
6310:   for (k = nnz1 - 1; k >= 0; k--) { /* k loops over imap[] */
6311:     for (; p > imap[k]; p--) jmap_new[p] = jmap[k + 1];
6312:   }
6313:   for (; p >= 0; p--) jmap_new[p] = jmap[0];
6314:   PetscFunctionReturn(PETSC_SUCCESS);
6315: }

6317: static PetscErrorCode MatCOOStructDestroy_MPIAIJ(void **data)
6318: {
6319:   MatCOOStruct_MPIAIJ *coo = (MatCOOStruct_MPIAIJ *)*data;

6321:   PetscFunctionBegin;
6322:   PetscCall(PetscSFDestroy(&coo->sf));
6323:   PetscCall(PetscFree(coo->Aperm1));
6324:   PetscCall(PetscFree(coo->Bperm1));
6325:   PetscCall(PetscFree(coo->Ajmap1));
6326:   PetscCall(PetscFree(coo->Bjmap1));
6327:   PetscCall(PetscFree(coo->Aimap2));
6328:   PetscCall(PetscFree(coo->Bimap2));
6329:   PetscCall(PetscFree(coo->Aperm2));
6330:   PetscCall(PetscFree(coo->Bperm2));
6331:   PetscCall(PetscFree(coo->Ajmap2));
6332:   PetscCall(PetscFree(coo->Bjmap2));
6333:   PetscCall(PetscFree(coo->Cperm1));
6334:   PetscCall(PetscFree2(coo->sendbuf, coo->recvbuf));
6335:   PetscCall(PetscFree(coo));
6336:   PetscFunctionReturn(PETSC_SUCCESS);
6337: }

6339: PetscErrorCode MatSetPreallocationCOO_MPIAIJ(Mat mat, PetscCount coo_n, PetscInt coo_i[], PetscInt coo_j[])
6340: {
6341:   MPI_Comm             comm;
6342:   PetscMPIInt          rank, size;
6343:   PetscInt             m, n, M, N, rstart, rend, cstart, cend; /* Sizes, indices of row/col, therefore with type PetscInt */
6344:   PetscCount           k, p, q, rem;                           /* Loop variables over coo arrays */
6345:   Mat_MPIAIJ          *mpiaij = (Mat_MPIAIJ *)mat->data;
6346:   PetscContainer       container;
6347:   MatCOOStruct_MPIAIJ *coo;

6349:   PetscFunctionBegin;
6350:   PetscCall(PetscFree(mpiaij->garray));
6351:   PetscCall(VecDestroy(&mpiaij->lvec));
6352: #if defined(PETSC_USE_CTABLE)
6353:   PetscCall(PetscHMapIDestroy(&mpiaij->colmap));
6354: #else
6355:   PetscCall(PetscFree(mpiaij->colmap));
6356: #endif
6357:   PetscCall(VecScatterDestroy(&mpiaij->Mvctx));
6358:   mat->assembled     = PETSC_FALSE;
6359:   mat->was_assembled = PETSC_FALSE;

6361:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
6362:   PetscCallMPI(MPI_Comm_size(comm, &size));
6363:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
6364:   PetscCall(PetscLayoutSetUp(mat->rmap));
6365:   PetscCall(PetscLayoutSetUp(mat->cmap));
6366:   PetscCall(PetscLayoutGetRange(mat->rmap, &rstart, &rend));
6367:   PetscCall(PetscLayoutGetRange(mat->cmap, &cstart, &cend));
6368:   PetscCall(MatGetLocalSize(mat, &m, &n));
6369:   PetscCall(MatGetSize(mat, &M, &N));

6371:   /* Sort (i,j) by row along with a permutation array, so that the to-be-ignored */
6372:   /* entries come first, then local rows, then remote rows.                     */
6373:   PetscCount n1 = coo_n, *perm1;
6374:   PetscInt  *i1 = coo_i, *j1 = coo_j;

6376:   PetscCall(PetscMalloc1(n1, &perm1));
6377:   for (k = 0; k < n1; k++) perm1[k] = k;

6379:   /* Manipulate indices so that entries with negative row or col indices will have smallest
6380:      row indices, local entries will have greater but negative row indices, and remote entries
6381:      will have positive row indices.
6382:   */
6383:   for (k = 0; k < n1; k++) {
6384:     if (i1[k] < 0 || j1[k] < 0) i1[k] = PETSC_INT_MIN;                /* e.g., -2^31, minimal to move them ahead */
6385:     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] */
6386:     else {
6387:       PetscCheck(!mat->nooffprocentries, PETSC_COMM_SELF, PETSC_ERR_USER_INPUT, "MAT_NO_OFF_PROC_ENTRIES is set but insert to remote rows");
6388:       if (mpiaij->donotstash) i1[k] = PETSC_INT_MIN; /* Ignore offproc entries as if they had negative indices */
6389:     }
6390:   }

6392:   /* Sort by row; after that, [0,k) have ignored entries, [k,rem) have local rows and [rem,n1) have remote rows */
6393:   PetscCall(PetscSortIntWithIntCountArrayPair(n1, i1, j1, perm1));

6395:   /* Advance k to the first entry we need to take care of */
6396:   for (k = 0; k < n1; k++)
6397:     if (i1[k] > PETSC_INT_MIN) break;
6398:   PetscCount i1start = k;

6400:   PetscCall(PetscSortedIntUpperBound(i1, k, n1, rend - 1 - PETSC_INT_MAX, &rem)); /* rem is upper bound of the last local row */
6401:   for (; k < rem; k++) i1[k] += PETSC_INT_MAX;                                    /* Revert row indices of local rows*/

6403:   PetscCheck(n1 == 0 || i1[n1 - 1] < M, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "COO row index %" PetscInt_FMT " is >= the matrix row size %" PetscInt_FMT, i1[n1 - 1], M);

6405:   /*           Send remote rows to their owner                                  */
6406:   /* Find which rows should be sent to which remote ranks*/
6407:   PetscInt        nsend = 0; /* Number of MPI ranks to send data to */
6408:   PetscMPIInt    *sendto;    /* [nsend], storing remote ranks */
6409:   PetscInt       *nentries;  /* [nsend], storing number of entries sent to remote ranks; Assume PetscInt is big enough for this count, and error if not */
6410:   const PetscInt *ranges;
6411:   PetscInt        maxNsend = size >= 128 ? 128 : size; /* Assume max 128 neighbors; realloc when needed */

6413:   PetscCall(PetscLayoutGetRanges(mat->rmap, &ranges));
6414:   PetscCall(PetscMalloc2(maxNsend, &sendto, maxNsend, &nentries));
6415:   for (k = rem; k < n1;) {
6416:     PetscMPIInt owner;
6417:     PetscInt    firstRow, lastRow;

6419:     /* Locate a row range */
6420:     firstRow = i1[k]; /* first row of this owner */
6421:     PetscCall(PetscLayoutFindOwner(mat->rmap, firstRow, &owner));
6422:     lastRow = ranges[owner + 1] - 1; /* last row of this owner */

6424:     /* Find the first index 'p' in [k,n) with i1[p] belonging to next owner */
6425:     PetscCall(PetscSortedIntUpperBound(i1, k, n1, lastRow, &p));

6427:     /* All entries in [k,p) belong to this remote owner */
6428:     if (nsend >= maxNsend) { /* Double the remote ranks arrays if not long enough */
6429:       PetscMPIInt *sendto2;
6430:       PetscInt    *nentries2;
6431:       PetscInt     maxNsend2 = (maxNsend <= size / 2) ? maxNsend * 2 : size;

6433:       PetscCall(PetscMalloc2(maxNsend2, &sendto2, maxNsend2, &nentries2));
6434:       PetscCall(PetscArraycpy(sendto2, sendto, maxNsend));
6435:       PetscCall(PetscArraycpy(nentries2, nentries2, maxNsend + 1));
6436:       PetscCall(PetscFree2(sendto, nentries2));
6437:       sendto   = sendto2;
6438:       nentries = nentries2;
6439:       maxNsend = maxNsend2;
6440:     }
6441:     sendto[nsend] = owner;
6442:     PetscCall(PetscIntCast(p - k, &nentries[nsend]));
6443:     nsend++;
6444:     k = p;
6445:   }

6447:   /* Build 1st SF to know offsets on remote to send data */
6448:   PetscSF      sf1;
6449:   PetscInt     nroots = 1, nroots2 = 0;
6450:   PetscInt     nleaves = nsend, nleaves2 = 0;
6451:   PetscInt    *offsets;
6452:   PetscSFNode *iremote;

6454:   PetscCall(PetscSFCreate(comm, &sf1));
6455:   PetscCall(PetscMalloc1(nsend, &iremote));
6456:   PetscCall(PetscMalloc1(nsend, &offsets));
6457:   for (k = 0; k < nsend; k++) {
6458:     iremote[k].rank  = sendto[k];
6459:     iremote[k].index = 0;
6460:     nleaves2 += nentries[k];
6461:     PetscCheck(nleaves2 >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of SF leaves is too large for PetscInt");
6462:   }
6463:   PetscCall(PetscSFSetGraph(sf1, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
6464:   PetscCall(PetscSFFetchAndOpWithMemTypeBegin(sf1, MPIU_INT, PETSC_MEMTYPE_HOST, &nroots2 /*rootdata*/, PETSC_MEMTYPE_HOST, nentries /*leafdata*/, PETSC_MEMTYPE_HOST, offsets /*leafupdate*/, MPI_SUM));
6465:   PetscCall(PetscSFFetchAndOpEnd(sf1, MPIU_INT, &nroots2, nentries, offsets, MPI_SUM)); /* Would nroots2 overflow, we check offsets[] below */
6466:   PetscCall(PetscSFDestroy(&sf1));
6467:   PetscAssert(nleaves2 == n1 - rem, PETSC_COMM_SELF, PETSC_ERR_PLIB, "nleaves2 %" PetscInt_FMT " != number of remote entries %" PetscCount_FMT, nleaves2, n1 - rem);

6469:   /* Build 2nd SF to send remote COOs to their owner */
6470:   PetscSF sf2;
6471:   nroots  = nroots2;
6472:   nleaves = nleaves2;
6473:   PetscCall(PetscSFCreate(comm, &sf2));
6474:   PetscCall(PetscSFSetFromOptions(sf2));
6475:   PetscCall(PetscMalloc1(nleaves, &iremote));
6476:   p = 0;
6477:   for (k = 0; k < nsend; k++) {
6478:     PetscCheck(offsets[k] >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of SF roots is too large for PetscInt");
6479:     for (q = 0; q < nentries[k]; q++, p++) {
6480:       iremote[p].rank = sendto[k];
6481:       PetscCall(PetscIntCast(offsets[k] + q, &iremote[p].index));
6482:     }
6483:   }
6484:   PetscCall(PetscSFSetGraph(sf2, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));

6486:   /* Send the remote COOs to their owner */
6487:   PetscInt    n2 = nroots, *i2, *j2; /* Buffers for received COOs from other ranks, along with a permutation array */
6488:   PetscCount *perm2;                 /* Though PetscInt is enough for remote entries, we use PetscCount here as we want to reuse MatSplitEntries_Internal() */
6489:   PetscCall(PetscMalloc3(n2, &i2, n2, &j2, n2, &perm2));
6490:   PetscAssert(rem == 0 || i1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6491:   PetscAssert(rem == 0 || j1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6492:   PetscInt *i1prem = PetscSafePointerPlusOffset(i1, rem);
6493:   PetscInt *j1prem = PetscSafePointerPlusOffset(j1, rem);
6494:   PetscCall(PetscSFReduceWithMemTypeBegin(sf2, MPIU_INT, PETSC_MEMTYPE_HOST, i1prem, PETSC_MEMTYPE_HOST, i2, MPI_REPLACE));
6495:   PetscCall(PetscSFReduceEnd(sf2, MPIU_INT, i1prem, i2, MPI_REPLACE));
6496:   PetscCall(PetscSFReduceWithMemTypeBegin(sf2, MPIU_INT, PETSC_MEMTYPE_HOST, j1prem, PETSC_MEMTYPE_HOST, j2, MPI_REPLACE));
6497:   PetscCall(PetscSFReduceEnd(sf2, MPIU_INT, j1prem, j2, MPI_REPLACE));

6499:   PetscCall(PetscFree(offsets));
6500:   PetscCall(PetscFree2(sendto, nentries));

6502:   /* Sort received COOs by row along with the permutation array     */
6503:   for (k = 0; k < n2; k++) perm2[k] = k;
6504:   PetscCall(PetscSortIntWithIntCountArrayPair(n2, i2, j2, perm2));

6506:   /* sf2 only sends contiguous leafdata to contiguous rootdata. We record the permutation which will be used to fill leafdata */
6507:   PetscCount *Cperm1;
6508:   PetscAssert(rem == 0 || perm1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6509:   PetscCount *perm1prem = PetscSafePointerPlusOffset(perm1, rem);
6510:   PetscCall(PetscMalloc1(nleaves, &Cperm1));
6511:   PetscCall(PetscArraycpy(Cperm1, perm1prem, nleaves));

6513:   /* Support for HYPRE matrices, kind of a hack.
6514:      Swap min column with diagonal so that diagonal values will go first */
6515:   PetscBool hypre;
6516:   PetscCall(PetscStrcmp("_internal_COO_mat_for_hypre", ((PetscObject)mat)->name, &hypre));
6517:   if (hypre) {
6518:     PetscInt *minj;
6519:     PetscBT   hasdiag;

6521:     PetscCall(PetscBTCreate(m, &hasdiag));
6522:     PetscCall(PetscMalloc1(m, &minj));
6523:     for (k = 0; k < m; k++) minj[k] = PETSC_INT_MAX;
6524:     for (k = i1start; k < rem; k++) {
6525:       if (j1[k] < cstart || j1[k] >= cend) continue;
6526:       const PetscInt rindex = i1[k] - rstart;
6527:       if ((j1[k] - cstart) == rindex) PetscCall(PetscBTSet(hasdiag, rindex));
6528:       minj[rindex] = PetscMin(minj[rindex], j1[k]);
6529:     }
6530:     for (k = 0; k < n2; k++) {
6531:       if (j2[k] < cstart || j2[k] >= cend) continue;
6532:       const PetscInt rindex = i2[k] - rstart;
6533:       if ((j2[k] - cstart) == rindex) PetscCall(PetscBTSet(hasdiag, rindex));
6534:       minj[rindex] = PetscMin(minj[rindex], j2[k]);
6535:     }
6536:     for (k = i1start; k < rem; k++) {
6537:       const PetscInt rindex = i1[k] - rstart;
6538:       if (j1[k] < cstart || j1[k] >= cend || !PetscBTLookup(hasdiag, rindex)) continue;
6539:       if (j1[k] == minj[rindex]) j1[k] = i1[k] + (cstart - rstart);
6540:       else if ((j1[k] - cstart) == rindex) j1[k] = minj[rindex];
6541:     }
6542:     for (k = 0; k < n2; k++) {
6543:       const PetscInt rindex = i2[k] - rstart;
6544:       if (j2[k] < cstart || j2[k] >= cend || !PetscBTLookup(hasdiag, rindex)) continue;
6545:       if (j2[k] == minj[rindex]) j2[k] = i2[k] + (cstart - rstart);
6546:       else if ((j2[k] - cstart) == rindex) j2[k] = minj[rindex];
6547:     }
6548:     PetscCall(PetscBTDestroy(&hasdiag));
6549:     PetscCall(PetscFree(minj));
6550:   }

6552:   /* Split local COOs and received COOs into diag/offdiag portions */
6553:   PetscCount *rowBegin1, *rowMid1, *rowEnd1;
6554:   PetscCount *Ajmap1, *Aperm1, *Bjmap1, *Bperm1;
6555:   PetscCount  Annz1, Bnnz1, Atot1, Btot1;
6556:   PetscCount *rowBegin2, *rowMid2, *rowEnd2;
6557:   PetscCount *Ajmap2, *Aperm2, *Bjmap2, *Bperm2;
6558:   PetscCount  Annz2, Bnnz2, Atot2, Btot2;

6560:   PetscCall(PetscCalloc3(m, &rowBegin1, m, &rowMid1, m, &rowEnd1));
6561:   PetscCall(PetscCalloc3(m, &rowBegin2, m, &rowMid2, m, &rowEnd2));
6562:   PetscCall(MatSplitEntries_Internal(mat, rem, i1, j1, perm1, rowBegin1, rowMid1, rowEnd1, &Atot1, &Aperm1, &Annz1, &Ajmap1, &Btot1, &Bperm1, &Bnnz1, &Bjmap1));
6563:   PetscCall(MatSplitEntries_Internal(mat, n2, i2, j2, perm2, rowBegin2, rowMid2, rowEnd2, &Atot2, &Aperm2, &Annz2, &Ajmap2, &Btot2, &Bperm2, &Bnnz2, &Bjmap2));

6565:   /* Merge local COOs with received COOs: diag with diag, offdiag with offdiag */
6566:   PetscInt *Ai, *Bi;
6567:   PetscInt *Aj, *Bj;

6569:   PetscCall(PetscMalloc1(m + 1, &Ai));
6570:   PetscCall(PetscMalloc1(m + 1, &Bi));
6571:   PetscCall(PetscMalloc1(Annz1 + Annz2, &Aj)); /* Since local and remote entries might have dups, we might allocate excess memory */
6572:   PetscCall(PetscMalloc1(Bnnz1 + Bnnz2, &Bj));

6574:   PetscCount *Aimap1, *Bimap1, *Aimap2, *Bimap2;
6575:   PetscCall(PetscMalloc1(Annz1, &Aimap1));
6576:   PetscCall(PetscMalloc1(Bnnz1, &Bimap1));
6577:   PetscCall(PetscMalloc1(Annz2, &Aimap2));
6578:   PetscCall(PetscMalloc1(Bnnz2, &Bimap2));

6580:   PetscCall(MatMergeEntries_Internal(mat, j1, j2, rowBegin1, rowMid1, rowBegin2, rowMid2, Ajmap1, Ajmap2, Aimap1, Aimap2, Ai, Aj));
6581:   PetscCall(MatMergeEntries_Internal(mat, j1, j2, rowMid1, rowEnd1, rowMid2, rowEnd2, Bjmap1, Bjmap2, Bimap1, Bimap2, Bi, Bj));

6583:   /* Expand Ajmap1/Bjmap1 to make them based off nonzeros in A/B, since we     */
6584:   /* expect nonzeros in A/B most likely have local contributing entries        */
6585:   PetscInt    Annz = Ai[m];
6586:   PetscInt    Bnnz = Bi[m];
6587:   PetscCount *Ajmap1_new, *Bjmap1_new;

6589:   PetscCall(PetscMalloc1(Annz + 1, &Ajmap1_new));
6590:   PetscCall(PetscMalloc1(Bnnz + 1, &Bjmap1_new));

6592:   PetscCall(ExpandJmap_Internal(Annz1, Annz, Aimap1, Ajmap1, Ajmap1_new));
6593:   PetscCall(ExpandJmap_Internal(Bnnz1, Bnnz, Bimap1, Bjmap1, Bjmap1_new));

6595:   PetscCall(PetscFree(Aimap1));
6596:   PetscCall(PetscFree(Ajmap1));
6597:   PetscCall(PetscFree(Bimap1));
6598:   PetscCall(PetscFree(Bjmap1));
6599:   PetscCall(PetscFree3(rowBegin1, rowMid1, rowEnd1));
6600:   PetscCall(PetscFree3(rowBegin2, rowMid2, rowEnd2));
6601:   PetscCall(PetscFree(perm1));
6602:   PetscCall(PetscFree3(i2, j2, perm2));

6604:   Ajmap1 = Ajmap1_new;
6605:   Bjmap1 = Bjmap1_new;

6607:   /* Reallocate Aj, Bj once we know actual numbers of unique nonzeros in A and B */
6608:   if (Annz < Annz1 + Annz2) {
6609:     PetscInt *Aj_new;
6610:     PetscCall(PetscMalloc1(Annz, &Aj_new));
6611:     PetscCall(PetscArraycpy(Aj_new, Aj, Annz));
6612:     PetscCall(PetscFree(Aj));
6613:     Aj = Aj_new;
6614:   }

6616:   if (Bnnz < Bnnz1 + Bnnz2) {
6617:     PetscInt *Bj_new;
6618:     PetscCall(PetscMalloc1(Bnnz, &Bj_new));
6619:     PetscCall(PetscArraycpy(Bj_new, Bj, Bnnz));
6620:     PetscCall(PetscFree(Bj));
6621:     Bj = Bj_new;
6622:   }

6624:   /* Create new submatrices for on-process and off-process coupling                  */
6625:   PetscScalar     *Aa, *Ba;
6626:   MatType          rtype;
6627:   Mat_SeqAIJ      *a, *b;
6628:   PetscObjectState state;
6629:   PetscCall(PetscCalloc1(Annz, &Aa)); /* Zero matrix on device */
6630:   PetscCall(PetscCalloc1(Bnnz, &Ba));
6631:   /* make Aj[] local, i.e, based off the start column of the diagonal portion */
6632:   if (cstart) {
6633:     for (k = 0; k < Annz; k++) Aj[k] -= cstart;
6634:   }

6636:   PetscCall(MatGetRootType_Private(mat, &rtype));

6638:   MatSeqXAIJGetOptions_Private(mpiaij->A);
6639:   PetscCall(MatDestroy(&mpiaij->A));
6640:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, n, Ai, Aj, Aa, &mpiaij->A));
6641:   PetscCall(MatSetBlockSizesFromMats(mpiaij->A, mat, mat));
6642:   MatSeqXAIJRestoreOptions_Private(mpiaij->A);

6644:   MatSeqXAIJGetOptions_Private(mpiaij->B);
6645:   PetscCall(MatDestroy(&mpiaij->B));
6646:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, mat->cmap->N, Bi, Bj, Ba, &mpiaij->B));
6647:   PetscCall(MatSetBlockSizesFromMats(mpiaij->B, mat, mat));
6648:   MatSeqXAIJRestoreOptions_Private(mpiaij->B);

6650:   PetscCall(MatSetUpMultiply_MPIAIJ(mat));
6651:   mat->was_assembled = PETSC_TRUE; // was_assembled in effect means the Mvctx is built; doing so avoids redundant MatSetUpMultiply_MPIAIJ
6652:   state              = mpiaij->A->nonzerostate + mpiaij->B->nonzerostate;
6653:   PetscCallMPI(MPIU_Allreduce(&state, &mat->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)mat)));

6655:   a          = (Mat_SeqAIJ *)mpiaij->A->data;
6656:   b          = (Mat_SeqAIJ *)mpiaij->B->data;
6657:   a->free_a  = PETSC_TRUE;
6658:   a->free_ij = PETSC_TRUE;
6659:   b->free_a  = PETSC_TRUE;
6660:   b->free_ij = PETSC_TRUE;
6661:   a->maxnz   = a->nz;
6662:   b->maxnz   = b->nz;

6664:   /* conversion must happen AFTER multiply setup */
6665:   PetscCall(MatConvert(mpiaij->A, rtype, MAT_INPLACE_MATRIX, &mpiaij->A));
6666:   PetscCall(MatConvert(mpiaij->B, rtype, MAT_INPLACE_MATRIX, &mpiaij->B));
6667:   PetscCall(VecDestroy(&mpiaij->lvec));
6668:   PetscCall(MatCreateVecs(mpiaij->B, &mpiaij->lvec, NULL));

6670:   // Put the COO struct in a container and then attach that to the matrix
6671:   PetscCall(PetscMalloc1(1, &coo));
6672:   coo->n       = coo_n;
6673:   coo->sf      = sf2;
6674:   coo->sendlen = nleaves;
6675:   coo->recvlen = nroots;
6676:   coo->Annz    = Annz;
6677:   coo->Bnnz    = Bnnz;
6678:   coo->Annz2   = Annz2;
6679:   coo->Bnnz2   = Bnnz2;
6680:   coo->Atot1   = Atot1;
6681:   coo->Atot2   = Atot2;
6682:   coo->Btot1   = Btot1;
6683:   coo->Btot2   = Btot2;
6684:   coo->Ajmap1  = Ajmap1;
6685:   coo->Aperm1  = Aperm1;
6686:   coo->Bjmap1  = Bjmap1;
6687:   coo->Bperm1  = Bperm1;
6688:   coo->Aimap2  = Aimap2;
6689:   coo->Ajmap2  = Ajmap2;
6690:   coo->Aperm2  = Aperm2;
6691:   coo->Bimap2  = Bimap2;
6692:   coo->Bjmap2  = Bjmap2;
6693:   coo->Bperm2  = Bperm2;
6694:   coo->Cperm1  = Cperm1;
6695:   // Allocate in preallocation. If not used, it has zero cost on host
6696:   PetscCall(PetscMalloc2(coo->sendlen, &coo->sendbuf, coo->recvlen, &coo->recvbuf));
6697:   PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &container));
6698:   PetscCall(PetscContainerSetPointer(container, coo));
6699:   PetscCall(PetscContainerSetCtxDestroy(container, MatCOOStructDestroy_MPIAIJ));
6700:   PetscCall(PetscObjectCompose((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject)container));
6701:   PetscCall(PetscContainerDestroy(&container));
6702:   PetscFunctionReturn(PETSC_SUCCESS);
6703: }

6705: static PetscErrorCode MatSetValuesCOO_MPIAIJ(Mat mat, const PetscScalar v[], InsertMode imode)
6706: {
6707:   Mat_MPIAIJ          *mpiaij = (Mat_MPIAIJ *)mat->data;
6708:   Mat                  A = mpiaij->A, B = mpiaij->B;
6709:   PetscScalar         *Aa, *Ba;
6710:   PetscScalar         *sendbuf, *recvbuf;
6711:   const PetscCount    *Ajmap1, *Ajmap2, *Aimap2;
6712:   const PetscCount    *Bjmap1, *Bjmap2, *Bimap2;
6713:   const PetscCount    *Aperm1, *Aperm2, *Bperm1, *Bperm2;
6714:   const PetscCount    *Cperm1;
6715:   PetscContainer       container;
6716:   MatCOOStruct_MPIAIJ *coo;

6718:   PetscFunctionBegin;
6719:   PetscCall(PetscObjectQuery((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject *)&container));
6720:   PetscCheck(container, PetscObjectComm((PetscObject)mat), PETSC_ERR_PLIB, "Not found MatCOOStruct on this matrix");
6721:   PetscCall(PetscContainerGetPointer(container, (void **)&coo));
6722:   sendbuf = coo->sendbuf;
6723:   recvbuf = coo->recvbuf;
6724:   Ajmap1  = coo->Ajmap1;
6725:   Ajmap2  = coo->Ajmap2;
6726:   Aimap2  = coo->Aimap2;
6727:   Bjmap1  = coo->Bjmap1;
6728:   Bjmap2  = coo->Bjmap2;
6729:   Bimap2  = coo->Bimap2;
6730:   Aperm1  = coo->Aperm1;
6731:   Aperm2  = coo->Aperm2;
6732:   Bperm1  = coo->Bperm1;
6733:   Bperm2  = coo->Bperm2;
6734:   Cperm1  = coo->Cperm1;

6736:   PetscCall(MatSeqAIJGetArray(A, &Aa)); /* Might read and write matrix values */
6737:   PetscCall(MatSeqAIJGetArray(B, &Ba));

6739:   /* Pack entries to be sent to remote */
6740:   for (PetscCount i = 0; i < coo->sendlen; i++) sendbuf[i] = v[Cperm1[i]];

6742:   /* Send remote entries to their owner and overlap the communication with local computation */
6743:   PetscCall(PetscSFReduceWithMemTypeBegin(coo->sf, MPIU_SCALAR, PETSC_MEMTYPE_HOST, sendbuf, PETSC_MEMTYPE_HOST, recvbuf, MPI_REPLACE));
6744:   /* Add local entries to A and B */
6745:   for (PetscCount i = 0; i < coo->Annz; i++) { /* All nonzeros in A are either zero'ed or added with a value (i.e., initialized) */
6746:     PetscScalar sum = 0.0;                     /* Do partial summation first to improve numerical stability */
6747:     for (PetscCount k = Ajmap1[i]; k < Ajmap1[i + 1]; k++) sum += v[Aperm1[k]];
6748:     Aa[i] = (imode == INSERT_VALUES ? 0.0 : Aa[i]) + sum;
6749:   }
6750:   for (PetscCount i = 0; i < coo->Bnnz; i++) {
6751:     PetscScalar sum = 0.0;
6752:     for (PetscCount k = Bjmap1[i]; k < Bjmap1[i + 1]; k++) sum += v[Bperm1[k]];
6753:     Ba[i] = (imode == INSERT_VALUES ? 0.0 : Ba[i]) + sum;
6754:   }
6755:   PetscCall(PetscSFReduceEnd(coo->sf, MPIU_SCALAR, sendbuf, recvbuf, MPI_REPLACE));

6757:   /* Add received remote entries to A and B */
6758:   for (PetscCount i = 0; i < coo->Annz2; i++) {
6759:     for (PetscCount k = Ajmap2[i]; k < Ajmap2[i + 1]; k++) Aa[Aimap2[i]] += recvbuf[Aperm2[k]];
6760:   }
6761:   for (PetscCount i = 0; i < coo->Bnnz2; i++) {
6762:     for (PetscCount k = Bjmap2[i]; k < Bjmap2[i + 1]; k++) Ba[Bimap2[i]] += recvbuf[Bperm2[k]];
6763:   }
6764:   PetscCall(MatSeqAIJRestoreArray(A, &Aa));
6765:   PetscCall(MatSeqAIJRestoreArray(B, &Ba));
6766:   PetscFunctionReturn(PETSC_SUCCESS);
6767: }

6769: /*MC
6770:    MATMPIAIJ - MATMPIAIJ = "mpiaij" - A matrix type to be used for parallel sparse matrices.

6772:    Options Database Keys:
6773: . -mat_type mpiaij - sets the matrix type to `MATMPIAIJ` during a call to `MatSetFromOptions()`

6775:    Level: beginner

6777:    Notes:
6778:    `MatSetValues()` may be called for this matrix type with a `NULL` argument for the numerical values,
6779:     in this case the values associated with the rows and columns one passes in are set to zero
6780:     in the matrix

6782:     `MatSetOptions`(,`MAT_STRUCTURE_ONLY`,`PETSC_TRUE`) may be called for this matrix type. In this no
6783:     space is allocated for the nonzero entries and any entries passed with `MatSetValues()` are ignored

6785: .seealso: [](ch_matrices), `Mat`, `MATSEQAIJ`, `MATAIJ`, `MatCreateAIJ()`
6786: M*/
6787: PETSC_EXTERN PetscErrorCode MatCreate_MPIAIJ(Mat B)
6788: {
6789:   Mat_MPIAIJ *b;
6790:   PetscMPIInt size;

6792:   PetscFunctionBegin;
6793:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)B), &size));

6795:   PetscCall(PetscNew(&b));
6796:   B->data       = (void *)b;
6797:   B->ops[0]     = MatOps_Values;
6798:   B->assembled  = PETSC_FALSE;
6799:   B->insertmode = NOT_SET_VALUES;
6800:   b->size       = size;

6802:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)B), &b->rank));

6804:   /* build cache for off array entries formed */
6805:   PetscCall(MatStashCreate_Private(PetscObjectComm((PetscObject)B), 1, &B->stash));

6807:   b->donotstash  = PETSC_FALSE;
6808:   b->colmap      = NULL;
6809:   b->garray      = NULL;
6810:   b->roworiented = PETSC_TRUE;

6812:   /* stuff used for matrix vector multiply */
6813:   b->lvec  = NULL;
6814:   b->Mvctx = NULL;

6816:   /* stuff for MatGetRow() */
6817:   b->rowindices   = NULL;
6818:   b->rowvalues    = NULL;
6819:   b->getrowactive = PETSC_FALSE;

6821:   /* flexible pointer used in CUSPARSE classes */
6822:   b->spptr = NULL;

6824:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetUseScalableIncreaseOverlap_C", MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ));
6825:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatStoreValues_C", MatStoreValues_MPIAIJ));
6826:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatRetrieveValues_C", MatRetrieveValues_MPIAIJ));
6827:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatIsTranspose_C", MatIsTranspose_MPIAIJ));
6828:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetPreallocation_C", MatMPIAIJSetPreallocation_MPIAIJ));
6829:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatResetPreallocation_C", MatResetPreallocation_MPIAIJ));
6830:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatResetHash_C", MatResetHash_MPIAIJ));
6831:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetPreallocationCSR_C", MatMPIAIJSetPreallocationCSR_MPIAIJ));
6832:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatDiagonalScaleLocal_C", MatDiagonalScaleLocal_MPIAIJ));
6833:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijperm_C", MatConvert_MPIAIJ_MPIAIJPERM));
6834:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijsell_C", MatConvert_MPIAIJ_MPIAIJSELL));
6835: #if defined(PETSC_HAVE_CUDA)
6836:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijcusparse_C", MatConvert_MPIAIJ_MPIAIJCUSPARSE));
6837: #endif
6838: #if defined(PETSC_HAVE_HIP)
6839:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijhipsparse_C", MatConvert_MPIAIJ_MPIAIJHIPSPARSE));
6840: #endif
6841: #if defined(PETSC_HAVE_KOKKOS_KERNELS)
6842:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijkokkos_C", MatConvert_MPIAIJ_MPIAIJKokkos));
6843: #endif
6844: #if defined(PETSC_HAVE_MKL_SPARSE)
6845:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijmkl_C", MatConvert_MPIAIJ_MPIAIJMKL));
6846: #endif
6847:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijcrl_C", MatConvert_MPIAIJ_MPIAIJCRL));
6848:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpibaij_C", MatConvert_MPIAIJ_MPIBAIJ));
6849:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpisbaij_C", MatConvert_MPIAIJ_MPISBAIJ));
6850:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpidense_C", MatConvert_MPIAIJ_MPIDense));
6851: #if defined(PETSC_HAVE_ELEMENTAL)
6852:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_elemental_C", MatConvert_MPIAIJ_Elemental));
6853: #endif
6854: #if defined(PETSC_HAVE_SCALAPACK) && (defined(PETSC_USE_REAL_SINGLE) || defined(PETSC_USE_REAL_DOUBLE))
6855:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_scalapack_C", MatConvert_AIJ_ScaLAPACK));
6856: #endif
6857:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_is_C", MatConvert_XAIJ_IS));
6858:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpisell_C", MatConvert_MPIAIJ_MPISELL));
6859: #if defined(PETSC_HAVE_HYPRE)
6860:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_hypre_C", MatConvert_AIJ_HYPRE));
6861:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_transpose_mpiaij_mpiaij_C", MatProductSetFromOptions_Transpose_AIJ_AIJ));
6862: #endif
6863:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_is_mpiaij_C", MatProductSetFromOptions_IS_XAIJ));
6864:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_mpiaij_mpiaij_C", MatProductSetFromOptions_MPIAIJ));
6865:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatSetPreallocationCOO_C", MatSetPreallocationCOO_MPIAIJ));
6866:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatSetValuesCOO_C", MatSetValuesCOO_MPIAIJ));
6867:   PetscCall(PetscObjectChangeTypeName((PetscObject)B, MATMPIAIJ));
6868:   PetscFunctionReturn(PETSC_SUCCESS);
6869: }

6871: /*@
6872:   MatCreateMPIAIJWithSplitArrays - creates a `MATMPIAIJ` matrix using arrays that contain the "diagonal"
6873:   and "off-diagonal" part of the matrix in CSR format.

6875:   Collective

6877:   Input Parameters:
6878: + comm - MPI communicator
6879: . m    - number of local rows (Cannot be `PETSC_DECIDE`)
6880: . n    - This value should be the same as the local size used in creating the
6881:          x vector for the matrix-vector product $y = Ax$. (or `PETSC_DECIDE` to have
6882:          calculated if `N` is given) For square matrices `n` is almost always `m`.
6883: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if `m` is given)
6884: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if `n` is given)
6885: . 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
6886: . j    - column indices, which must be local, i.e., based off the start column of the diagonal portion
6887: . a    - matrix values
6888: . 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
6889: . oj   - column indices, which must be global, representing global columns in the `MATMPIAIJ` matrix
6890: - oa   - matrix values

6892:   Output Parameter:
6893: . mat - the matrix

6895:   Level: advanced

6897:   Notes:
6898:   The `i`, `j`, and `a` arrays ARE NOT copied by this routine into the internal format used by PETSc (even in Fortran). The user
6899:   must free the arrays once the matrix has been destroyed and not before.

6901:   The `i` and `j` indices are 0 based

6903:   See `MatCreateAIJ()` for the definition of "diagonal" and "off-diagonal" portion of the matrix

6905:   This sets local rows and cannot be used to set off-processor values.

6907:   Use of this routine is discouraged because it is inflexible and cumbersome to use. It is extremely rare that a
6908:   legacy application natively assembles into exactly this split format. The code to do so is nontrivial and does
6909:   not easily support in-place reassembly. It is recommended to use MatSetValues() (or a variant thereof) because
6910:   the resulting assembly is easier to implement, will work with any matrix format, and the user does not have to
6911:   keep track of the underlying array. Use `MatSetOption`(A,`MAT_NO_OFF_PROC_ENTRIES`,`PETSC_TRUE`) to disable all
6912:   communication if it is known that only local entries will be set.

6914: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
6915:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithArrays()`
6916: @*/
6917: 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)
6918: {
6919:   Mat_MPIAIJ *maij;

6921:   PetscFunctionBegin;
6922:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
6923:   PetscCheck(i[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
6924:   PetscCheck(oi[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "oi (row indices) must start with 0");
6925:   PetscCall(MatCreate(comm, mat));
6926:   PetscCall(MatSetSizes(*mat, m, n, M, N));
6927:   PetscCall(MatSetType(*mat, MATMPIAIJ));
6928:   maij = (Mat_MPIAIJ *)(*mat)->data;

6930:   (*mat)->preallocated = PETSC_TRUE;

6932:   PetscCall(PetscLayoutSetUp((*mat)->rmap));
6933:   PetscCall(PetscLayoutSetUp((*mat)->cmap));

6935:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, n, i, j, a, &maij->A));
6936:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, (*mat)->cmap->N, oi, oj, oa, &maij->B));

6938:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
6939:   PetscCall(MatAssemblyBegin(*mat, MAT_FINAL_ASSEMBLY));
6940:   PetscCall(MatAssemblyEnd(*mat, MAT_FINAL_ASSEMBLY));
6941:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_FALSE));
6942:   PetscCall(MatSetOption(*mat, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
6943:   PetscFunctionReturn(PETSC_SUCCESS);
6944: }

6946: typedef struct {
6947:   Mat       *mp;    /* intermediate products */
6948:   PetscBool *mptmp; /* is the intermediate product temporary ? */
6949:   PetscInt   cp;    /* number of intermediate products */

6951:   /* support for MatGetBrowsOfAoCols_MPIAIJ for P_oth */
6952:   PetscInt    *startsj_s, *startsj_r;
6953:   PetscScalar *bufa;
6954:   Mat          P_oth;

6956:   /* may take advantage of merging product->B */
6957:   Mat Bloc; /* B-local by merging diag and off-diag */

6959:   /* cusparse does not have support to split between symbolic and numeric phases.
6960:      When api_user is true, we don't need to update the numerical values
6961:      of the temporary storage */
6962:   PetscBool reusesym;

6964:   /* support for COO values insertion */
6965:   PetscScalar *coo_v, *coo_w; /* store on-process and off-process COO scalars, and used as MPI recv/send buffers respectively */
6966:   PetscInt   **own;           /* own[i] points to address of on-process COO indices for Mat mp[i] */
6967:   PetscInt   **off;           /* off[i] points to address of off-process COO indices for Mat mp[i] */
6968:   PetscBool    hasoffproc;    /* if true, have off-process values insertion (i.e. AtB or PtAP) */
6969:   PetscSF      sf;            /* used for non-local values insertion and memory malloc */
6970:   PetscMemType mtype;

6972:   /* customization */
6973:   PetscBool abmerge;
6974:   PetscBool P_oth_bind;
6975: } MatMatMPIAIJBACKEND;

6977: static PetscErrorCode MatProductCtxDestroy_MatMatMPIAIJBACKEND(void **data)
6978: {
6979:   MatMatMPIAIJBACKEND *mmdata = *(MatMatMPIAIJBACKEND **)data;
6980:   PetscInt             i;

6982:   PetscFunctionBegin;
6983:   PetscCall(PetscFree2(mmdata->startsj_s, mmdata->startsj_r));
6984:   PetscCall(PetscFree(mmdata->bufa));
6985:   PetscCall(PetscSFFree(mmdata->sf, mmdata->mtype, mmdata->coo_v));
6986:   PetscCall(PetscSFFree(mmdata->sf, mmdata->mtype, mmdata->coo_w));
6987:   PetscCall(MatDestroy(&mmdata->P_oth));
6988:   PetscCall(MatDestroy(&mmdata->Bloc));
6989:   PetscCall(PetscSFDestroy(&mmdata->sf));
6990:   for (i = 0; i < mmdata->cp; i++) PetscCall(MatDestroy(&mmdata->mp[i]));
6991:   PetscCall(PetscFree2(mmdata->mp, mmdata->mptmp));
6992:   PetscCall(PetscFree(mmdata->own[0]));
6993:   PetscCall(PetscFree(mmdata->own));
6994:   PetscCall(PetscFree(mmdata->off[0]));
6995:   PetscCall(PetscFree(mmdata->off));
6996:   PetscCall(PetscFree(mmdata));
6997:   PetscFunctionReturn(PETSC_SUCCESS);
6998: }

7000: /* Copy selected n entries with indices in idx[] of A to v[].
7001:    If idx is NULL, copy the whole data array of A to v[]
7002:  */
7003: static PetscErrorCode MatSeqAIJCopySubArray(Mat A, PetscInt n, const PetscInt idx[], PetscScalar v[])
7004: {
7005:   PetscErrorCode (*f)(Mat, PetscInt, const PetscInt[], PetscScalar[]);

7007:   PetscFunctionBegin;
7008:   PetscCall(PetscObjectQueryFunction((PetscObject)A, "MatSeqAIJCopySubArray_C", &f));
7009:   if (f) {
7010:     PetscCall((*f)(A, n, idx, v));
7011:   } else {
7012:     const PetscScalar *vv;

7014:     PetscCall(MatSeqAIJGetArrayRead(A, &vv));
7015:     if (n && idx) {
7016:       PetscScalar    *w  = v;
7017:       const PetscInt *oi = idx;
7018:       PetscInt        j;

7020:       for (j = 0; j < n; j++) *w++ = vv[*oi++];
7021:     } else {
7022:       PetscCall(PetscArraycpy(v, vv, n));
7023:     }
7024:     PetscCall(MatSeqAIJRestoreArrayRead(A, &vv));
7025:   }
7026:   PetscFunctionReturn(PETSC_SUCCESS);
7027: }

7029: static PetscErrorCode MatProductNumeric_MPIAIJBACKEND(Mat C)
7030: {
7031:   MatMatMPIAIJBACKEND *mmdata;
7032:   PetscInt             i, n_d, n_o;

7034:   PetscFunctionBegin;
7035:   MatCheckProduct(C, 1);
7036:   PetscCheck(C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data empty");
7037:   mmdata = (MatMatMPIAIJBACKEND *)C->product->data;
7038:   if (!mmdata->reusesym) { /* update temporary matrices */
7039:     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));
7040:     if (mmdata->Bloc) PetscCall(MatMPIAIJGetLocalMatMerge(C->product->B, MAT_REUSE_MATRIX, NULL, &mmdata->Bloc));
7041:   }
7042:   mmdata->reusesym = PETSC_FALSE;

7044:   for (i = 0; i < mmdata->cp; i++) {
7045:     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]);
7046:     PetscCall((*mmdata->mp[i]->ops->productnumeric)(mmdata->mp[i]));
7047:   }
7048:   for (i = 0, n_d = 0, n_o = 0; i < mmdata->cp; i++) {
7049:     PetscInt noff;

7051:     PetscCall(PetscIntCast(mmdata->off[i + 1] - mmdata->off[i], &noff));
7052:     if (mmdata->mptmp[i]) continue;
7053:     if (noff) {
7054:       PetscInt nown;

7056:       PetscCall(PetscIntCast(mmdata->own[i + 1] - mmdata->own[i], &nown));
7057:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], noff, mmdata->off[i], mmdata->coo_w + n_o));
7058:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], nown, mmdata->own[i], mmdata->coo_v + n_d));
7059:       n_o += noff;
7060:       n_d += nown;
7061:     } else {
7062:       Mat_SeqAIJ *mm = (Mat_SeqAIJ *)mmdata->mp[i]->data;

7064:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], mm->nz, NULL, mmdata->coo_v + n_d));
7065:       n_d += mm->nz;
7066:     }
7067:   }
7068:   if (mmdata->hasoffproc) { /* offprocess insertion */
7069:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_SCALAR, mmdata->coo_w, mmdata->coo_v + n_d));
7070:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_SCALAR, mmdata->coo_w, mmdata->coo_v + n_d));
7071:   }
7072:   PetscCall(MatSetValuesCOO(C, mmdata->coo_v, INSERT_VALUES));
7073:   PetscFunctionReturn(PETSC_SUCCESS);
7074: }

7076: /* Support for Pt * A, A * P, or Pt * A * P */
7077: #define MAX_NUMBER_INTERMEDIATE 4
7078: PetscErrorCode MatProductSymbolic_MPIAIJBACKEND(Mat C)
7079: {
7080:   Mat_Product           *product = C->product;
7081:   Mat                    A, P, mp[MAX_NUMBER_INTERMEDIATE]; /* A, P and a series of intermediate matrices */
7082:   Mat_MPIAIJ            *a, *p;
7083:   MatMatMPIAIJBACKEND   *mmdata;
7084:   ISLocalToGlobalMapping P_oth_l2g = NULL;
7085:   IS                     glob      = NULL;
7086:   const char            *prefix;
7087:   char                   pprefix[256];
7088:   const PetscInt        *globidx, *P_oth_idx;
7089:   PetscInt               i, j, cp, m, n, M, N, *coo_i, *coo_j;
7090:   PetscCount             ncoo, ncoo_d, ncoo_o, ncoo_oown;
7091:   PetscInt               cmapt[MAX_NUMBER_INTERMEDIATE], rmapt[MAX_NUMBER_INTERMEDIATE]; /* col/row map type for each Mat in mp[]. */
7092:                                                                                          /* type-0: consecutive, start from 0; type-1: consecutive with */
7093:                                                                                          /* a base offset; type-2: sparse with a local to global map table */
7094:   const PetscInt *cmapa[MAX_NUMBER_INTERMEDIATE], *rmapa[MAX_NUMBER_INTERMEDIATE];       /* col/row local to global map array (table) for type-2 map type */

7096:   MatProductType ptype;
7097:   PetscBool      mptmp[MAX_NUMBER_INTERMEDIATE], hasoffproc = PETSC_FALSE, iscuda, iship, iskokk;
7098:   PetscMPIInt    size;

7100:   PetscFunctionBegin;
7101:   MatCheckProduct(C, 1);
7102:   PetscCheck(!product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data not empty");
7103:   ptype = product->type;
7104:   if (product->A->symmetric == PETSC_BOOL3_TRUE && ptype == MATPRODUCT_AtB) {
7105:     ptype                                          = MATPRODUCT_AB;
7106:     product->symbolic_used_the_fact_A_is_symmetric = PETSC_TRUE;
7107:   }
7108:   switch (ptype) {
7109:   case MATPRODUCT_AB:
7110:     A          = product->A;
7111:     P          = product->B;
7112:     m          = A->rmap->n;
7113:     n          = P->cmap->n;
7114:     M          = A->rmap->N;
7115:     N          = P->cmap->N;
7116:     hasoffproc = PETSC_FALSE; /* will not scatter mat product values to other processes */
7117:     break;
7118:   case MATPRODUCT_AtB:
7119:     P          = product->A;
7120:     A          = product->B;
7121:     m          = P->cmap->n;
7122:     n          = A->cmap->n;
7123:     M          = P->cmap->N;
7124:     N          = A->cmap->N;
7125:     hasoffproc = PETSC_TRUE;
7126:     break;
7127:   case MATPRODUCT_PtAP:
7128:     A          = product->A;
7129:     P          = product->B;
7130:     m          = P->cmap->n;
7131:     n          = P->cmap->n;
7132:     M          = P->cmap->N;
7133:     N          = P->cmap->N;
7134:     hasoffproc = PETSC_TRUE;
7135:     break;
7136:   default:
7137:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[ptype]);
7138:   }
7139:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)C), &size));
7140:   if (size == 1) hasoffproc = PETSC_FALSE;

7142:   /* defaults */
7143:   for (i = 0; i < MAX_NUMBER_INTERMEDIATE; i++) {
7144:     mp[i]    = NULL;
7145:     mptmp[i] = PETSC_FALSE;
7146:     rmapt[i] = -1;
7147:     cmapt[i] = -1;
7148:     rmapa[i] = NULL;
7149:     cmapa[i] = NULL;
7150:   }

7152:   /* customization */
7153:   PetscCall(PetscNew(&mmdata));
7154:   mmdata->reusesym = product->api_user;
7155:   if (ptype == MATPRODUCT_AB) {
7156:     if (product->api_user) {
7157:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatMatMult", "Mat");
7158:       PetscCall(PetscOptionsBool("-matmatmult_backend_mergeB", "Merge product->B local matrices", "MatMatMult", mmdata->abmerge, &mmdata->abmerge, NULL));
7159:       PetscCall(PetscOptionsBool("-matmatmult_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7160:       PetscOptionsEnd();
7161:     } else {
7162:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_AB", "Mat");
7163:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_mergeB", "Merge product->B local matrices", "MatMatMult", mmdata->abmerge, &mmdata->abmerge, NULL));
7164:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7165:       PetscOptionsEnd();
7166:     }
7167:   } else if (ptype == MATPRODUCT_PtAP) {
7168:     if (product->api_user) {
7169:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatPtAP", "Mat");
7170:       PetscCall(PetscOptionsBool("-matptap_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7171:       PetscOptionsEnd();
7172:     } else {
7173:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_PtAP", "Mat");
7174:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7175:       PetscOptionsEnd();
7176:     }
7177:   }
7178:   a = (Mat_MPIAIJ *)A->data;
7179:   p = (Mat_MPIAIJ *)P->data;
7180:   PetscCall(MatSetSizes(C, m, n, M, N));
7181:   PetscCall(PetscLayoutSetUp(C->rmap));
7182:   PetscCall(PetscLayoutSetUp(C->cmap));
7183:   PetscCall(MatSetType(C, ((PetscObject)A)->type_name));
7184:   PetscCall(MatGetOptionsPrefix(C, &prefix));

7186:   cp = 0;
7187:   switch (ptype) {
7188:   case MATPRODUCT_AB: /* A * P */
7189:     PetscCall(MatGetBrowsOfAoCols_MPIAIJ(A, P, MAT_INITIAL_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));

7191:     /* A_diag * P_local (merged or not) */
7192:     if (mmdata->abmerge) { /* P's diagonal and off-diag blocks are merged to one matrix, then multiplied by A_diag */
7193:       /* P is product->B */
7194:       PetscCall(MatMPIAIJGetLocalMatMerge(P, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7195:       PetscCall(MatProductCreate(a->A, mmdata->Bloc, NULL, &mp[cp]));
7196:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7197:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7198:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7199:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7200:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7201:       mp[cp]->product->api_user = product->api_user;
7202:       PetscCall(MatProductSetFromOptions(mp[cp]));
7203:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7204:       PetscCall(ISGetIndices(glob, &globidx));
7205:       rmapt[cp] = 1;
7206:       cmapt[cp] = 2;
7207:       cmapa[cp] = globidx;
7208:       mptmp[cp] = PETSC_FALSE;
7209:       cp++;
7210:     } else { /* A_diag * P_diag and A_diag * P_off */
7211:       PetscCall(MatProductCreate(a->A, p->A, NULL, &mp[cp]));
7212:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7213:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7214:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7215:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7216:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7217:       mp[cp]->product->api_user = product->api_user;
7218:       PetscCall(MatProductSetFromOptions(mp[cp]));
7219:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7220:       rmapt[cp] = 1;
7221:       cmapt[cp] = 1;
7222:       mptmp[cp] = PETSC_FALSE;
7223:       cp++;
7224:       PetscCall(MatProductCreate(a->A, p->B, NULL, &mp[cp]));
7225:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7226:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7227:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7228:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7229:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7230:       mp[cp]->product->api_user = product->api_user;
7231:       PetscCall(MatProductSetFromOptions(mp[cp]));
7232:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7233:       rmapt[cp] = 1;
7234:       cmapt[cp] = 2;
7235:       cmapa[cp] = p->garray;
7236:       mptmp[cp] = PETSC_FALSE;
7237:       cp++;
7238:     }

7240:     /* A_off * P_other */
7241:     if (mmdata->P_oth) {
7242:       PetscCall(MatSeqAIJCompactOutExtraColumns_SeqAIJ(mmdata->P_oth, &P_oth_l2g)); /* make P_oth use local col ids */
7243:       PetscCall(ISLocalToGlobalMappingGetIndices(P_oth_l2g, &P_oth_idx));
7244:       PetscCall(MatSetType(mmdata->P_oth, ((PetscObject)a->B)->type_name));
7245:       PetscCall(MatBindToCPU(mmdata->P_oth, mmdata->P_oth_bind));
7246:       PetscCall(MatProductCreate(a->B, mmdata->P_oth, NULL, &mp[cp]));
7247:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7248:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7249:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7250:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7251:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7252:       mp[cp]->product->api_user = product->api_user;
7253:       PetscCall(MatProductSetFromOptions(mp[cp]));
7254:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7255:       rmapt[cp] = 1;
7256:       cmapt[cp] = 2;
7257:       cmapa[cp] = P_oth_idx;
7258:       mptmp[cp] = PETSC_FALSE;
7259:       cp++;
7260:     }
7261:     break;

7263:   case MATPRODUCT_AtB: /* (P^t * A): P_diag * A_loc + P_off * A_loc */
7264:     /* A is product->B */
7265:     PetscCall(MatMPIAIJGetLocalMatMerge(A, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7266:     if (A == P) { /* when A==P, we can take advantage of the already merged mmdata->Bloc */
7267:       PetscCall(MatProductCreate(mmdata->Bloc, mmdata->Bloc, NULL, &mp[cp]));
7268:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7269:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7270:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7271:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7272:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7273:       mp[cp]->product->api_user = product->api_user;
7274:       PetscCall(MatProductSetFromOptions(mp[cp]));
7275:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7276:       PetscCall(ISGetIndices(glob, &globidx));
7277:       rmapt[cp] = 2;
7278:       rmapa[cp] = globidx;
7279:       cmapt[cp] = 2;
7280:       cmapa[cp] = globidx;
7281:       mptmp[cp] = PETSC_FALSE;
7282:       cp++;
7283:     } else {
7284:       PetscCall(MatProductCreate(p->A, mmdata->Bloc, NULL, &mp[cp]));
7285:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7286:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7287:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7288:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7289:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7290:       mp[cp]->product->api_user = product->api_user;
7291:       PetscCall(MatProductSetFromOptions(mp[cp]));
7292:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7293:       PetscCall(ISGetIndices(glob, &globidx));
7294:       rmapt[cp] = 1;
7295:       cmapt[cp] = 2;
7296:       cmapa[cp] = globidx;
7297:       mptmp[cp] = PETSC_FALSE;
7298:       cp++;
7299:       PetscCall(MatProductCreate(p->B, 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:       rmapt[cp] = 2;
7309:       rmapa[cp] = p->garray;
7310:       cmapt[cp] = 2;
7311:       cmapa[cp] = globidx;
7312:       mptmp[cp] = PETSC_FALSE;
7313:       cp++;
7314:     }
7315:     break;
7316:   case MATPRODUCT_PtAP:
7317:     PetscCall(MatGetBrowsOfAoCols_MPIAIJ(A, P, MAT_INITIAL_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));
7318:     /* P is product->B */
7319:     PetscCall(MatMPIAIJGetLocalMatMerge(P, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7320:     PetscCall(MatProductCreate(a->A, mmdata->Bloc, NULL, &mp[cp]));
7321:     PetscCall(MatProductSetType(mp[cp], MATPRODUCT_PtAP));
7322:     PetscCall(MatProductSetFill(mp[cp], product->fill));
7323:     PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7324:     PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7325:     PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7326:     mp[cp]->product->api_user = product->api_user;
7327:     PetscCall(MatProductSetFromOptions(mp[cp]));
7328:     PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7329:     PetscCall(ISGetIndices(glob, &globidx));
7330:     rmapt[cp] = 2;
7331:     rmapa[cp] = globidx;
7332:     cmapt[cp] = 2;
7333:     cmapa[cp] = globidx;
7334:     mptmp[cp] = PETSC_FALSE;
7335:     cp++;
7336:     if (mmdata->P_oth) {
7337:       PetscCall(MatSeqAIJCompactOutExtraColumns_SeqAIJ(mmdata->P_oth, &P_oth_l2g));
7338:       PetscCall(ISLocalToGlobalMappingGetIndices(P_oth_l2g, &P_oth_idx));
7339:       PetscCall(MatSetType(mmdata->P_oth, ((PetscObject)a->B)->type_name));
7340:       PetscCall(MatBindToCPU(mmdata->P_oth, mmdata->P_oth_bind));
7341:       PetscCall(MatProductCreate(a->B, mmdata->P_oth, NULL, &mp[cp]));
7342:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7343:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7344:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7345:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7346:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7347:       mp[cp]->product->api_user = product->api_user;
7348:       PetscCall(MatProductSetFromOptions(mp[cp]));
7349:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7350:       mptmp[cp] = PETSC_TRUE;
7351:       cp++;
7352:       PetscCall(MatProductCreate(mmdata->Bloc, mp[1], NULL, &mp[cp]));
7353:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7354:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7355:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7356:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7357:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7358:       mp[cp]->product->api_user = product->api_user;
7359:       PetscCall(MatProductSetFromOptions(mp[cp]));
7360:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7361:       rmapt[cp] = 2;
7362:       rmapa[cp] = globidx;
7363:       cmapt[cp] = 2;
7364:       cmapa[cp] = P_oth_idx;
7365:       mptmp[cp] = PETSC_FALSE;
7366:       cp++;
7367:     }
7368:     break;
7369:   default:
7370:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[ptype]);
7371:   }
7372:   /* sanity check */
7373:   if (size > 1)
7374:     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);

7376:   PetscCall(PetscMalloc2(cp, &mmdata->mp, cp, &mmdata->mptmp));
7377:   for (i = 0; i < cp; i++) {
7378:     mmdata->mp[i]    = mp[i];
7379:     mmdata->mptmp[i] = mptmp[i];
7380:   }
7381:   mmdata->cp             = cp;
7382:   C->product->data       = mmdata;
7383:   C->product->destroy    = MatProductCtxDestroy_MatMatMPIAIJBACKEND;
7384:   C->ops->productnumeric = MatProductNumeric_MPIAIJBACKEND;

7386:   /* memory type */
7387:   mmdata->mtype = PETSC_MEMTYPE_HOST;
7388:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iscuda, MATSEQAIJCUSPARSE, MATMPIAIJCUSPARSE, ""));
7389:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iship, MATSEQAIJHIPSPARSE, MATMPIAIJHIPSPARSE, ""));
7390:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iskokk, MATSEQAIJKOKKOS, MATMPIAIJKOKKOS, ""));
7391:   if (iscuda) mmdata->mtype = PETSC_MEMTYPE_CUDA;
7392:   else if (iship) mmdata->mtype = PETSC_MEMTYPE_HIP;
7393:   else if (iskokk) mmdata->mtype = PETSC_MEMTYPE_KOKKOS;

7395:   /* prepare coo coordinates for values insertion */

7397:   /* count total nonzeros of those intermediate seqaij Mats
7398:     ncoo_d:    # of nonzeros of matrices that do not have offproc entries
7399:     ncoo_o:    # of nonzeros (of matrices that might have offproc entries) that will be inserted to remote procs
7400:     ncoo_oown: # of nonzeros (of matrices that might have offproc entries) that will be inserted locally
7401:   */
7402:   for (cp = 0, ncoo_d = 0, ncoo_o = 0, ncoo_oown = 0; cp < mmdata->cp; cp++) {
7403:     Mat_SeqAIJ *mm = (Mat_SeqAIJ *)mp[cp]->data;
7404:     if (mptmp[cp]) continue;
7405:     if (rmapt[cp] == 2 && hasoffproc) { /* the rows need to be scatter to all processes (might include self) */
7406:       const PetscInt *rmap = rmapa[cp];
7407:       const PetscInt  mr   = mp[cp]->rmap->n;
7408:       const PetscInt  rs   = C->rmap->rstart;
7409:       const PetscInt  re   = C->rmap->rend;
7410:       const PetscInt *ii   = mm->i;
7411:       for (i = 0; i < mr; i++) {
7412:         const PetscInt gr = rmap[i];
7413:         const PetscInt nz = ii[i + 1] - ii[i];
7414:         if (gr < rs || gr >= re) ncoo_o += nz; /* this row is offproc */
7415:         else ncoo_oown += nz;                  /* this row is local */
7416:       }
7417:     } else ncoo_d += mm->nz;
7418:   }

7420:   /*
7421:     ncoo: total number of nonzeros (including those inserted by remote procs) belonging to this proc

7423:     ncoo = ncoo_d + ncoo_oown + ncoo2, which ncoo2 is number of nonzeros inserted to me by other procs.

7425:     off[0] points to a big index array, which is shared by off[1,2,...]. Similarly, for own[0].

7427:     off[p]: points to the segment for matrix mp[p], storing location of nonzeros that mp[p] will insert to others
7428:     own[p]: points to the segment for matrix mp[p], storing location of nonzeros that mp[p] will insert locally
7429:     so, off[p+1]-off[p] is the number of nonzeros that mp[p] will send to others.

7431:     coo_i/j/v[]: [ncoo] row/col/val of nonzeros belonging to this proc.
7432:     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.
7433:   */
7434:   PetscCall(PetscCalloc1(mmdata->cp + 1, &mmdata->off)); /* +1 to make a csr-like data structure */
7435:   PetscCall(PetscCalloc1(mmdata->cp + 1, &mmdata->own));

7437:   /* gather (i,j) of nonzeros inserted by remote procs */
7438:   if (hasoffproc) {
7439:     PetscSF  msf;
7440:     PetscInt ncoo2, *coo_i2, *coo_j2;

7442:     PetscCall(PetscMalloc1(ncoo_o, &mmdata->off[0]));
7443:     PetscCall(PetscMalloc1(ncoo_oown, &mmdata->own[0]));
7444:     PetscCall(PetscMalloc2(ncoo_o, &coo_i, ncoo_o, &coo_j)); /* to collect (i,j) of entries to be sent to others */

7446:     for (cp = 0, ncoo_o = 0; cp < mmdata->cp; cp++) {
7447:       Mat_SeqAIJ *mm     = (Mat_SeqAIJ *)mp[cp]->data;
7448:       PetscInt   *idxoff = mmdata->off[cp];
7449:       PetscInt   *idxown = mmdata->own[cp];
7450:       if (!mptmp[cp] && rmapt[cp] == 2) { /* row map is sparse */
7451:         const PetscInt *rmap = rmapa[cp];
7452:         const PetscInt *cmap = cmapa[cp];
7453:         const PetscInt *ii   = mm->i;
7454:         PetscInt       *coi  = coo_i + ncoo_o;
7455:         PetscInt       *coj  = coo_j + ncoo_o;
7456:         const PetscInt  mr   = mp[cp]->rmap->n;
7457:         const PetscInt  rs   = C->rmap->rstart;
7458:         const PetscInt  re   = C->rmap->rend;
7459:         const PetscInt  cs   = C->cmap->rstart;
7460:         for (i = 0; i < mr; i++) {
7461:           const PetscInt *jj = mm->j + ii[i];
7462:           const PetscInt  gr = rmap[i];
7463:           const PetscInt  nz = ii[i + 1] - ii[i];
7464:           if (gr < rs || gr >= re) { /* this is an offproc row */
7465:             for (j = ii[i]; j < ii[i + 1]; j++) {
7466:               *coi++    = gr;
7467:               *idxoff++ = j;
7468:             }
7469:             if (!cmapt[cp]) { /* already global */
7470:               for (j = 0; j < nz; j++) *coj++ = jj[j];
7471:             } else if (cmapt[cp] == 1) { /* local to global for owned columns of C */
7472:               for (j = 0; j < nz; j++) *coj++ = jj[j] + cs;
7473:             } else { /* offdiag */
7474:               for (j = 0; j < nz; j++) *coj++ = cmap[jj[j]];
7475:             }
7476:             ncoo_o += nz;
7477:           } else { /* this is a local row */
7478:             for (j = ii[i]; j < ii[i + 1]; j++) *idxown++ = j;
7479:           }
7480:         }
7481:       }
7482:       mmdata->off[cp + 1] = idxoff;
7483:       mmdata->own[cp + 1] = idxown;
7484:     }

7486:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)C), &mmdata->sf));
7487:     PetscInt incoo_o;
7488:     PetscCall(PetscIntCast(ncoo_o, &incoo_o));
7489:     PetscCall(PetscSFSetGraphLayout(mmdata->sf, C->rmap, incoo_o /*nleaves*/, NULL /*ilocal*/, PETSC_OWN_POINTER, coo_i));
7490:     PetscCall(PetscSFGetMultiSF(mmdata->sf, &msf));
7491:     PetscCall(PetscSFGetGraph(msf, &ncoo2 /*nroots*/, NULL, NULL, NULL));
7492:     ncoo = ncoo_d + ncoo_oown + ncoo2;
7493:     PetscCall(PetscMalloc2(ncoo, &coo_i2, ncoo, &coo_j2));
7494:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_INT, coo_i, coo_i2 + ncoo_d + ncoo_oown)); /* put (i,j) of remote nonzeros at back */
7495:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_INT, coo_i, coo_i2 + ncoo_d + ncoo_oown));
7496:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_INT, coo_j, coo_j2 + ncoo_d + ncoo_oown));
7497:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_INT, coo_j, coo_j2 + ncoo_d + ncoo_oown));
7498:     PetscCall(PetscFree2(coo_i, coo_j));
7499:     /* allocate MPI send buffer to collect nonzero values to be sent to remote procs */
7500:     PetscCall(PetscSFMalloc(mmdata->sf, mmdata->mtype, ncoo_o * sizeof(PetscScalar), (void **)&mmdata->coo_w));
7501:     coo_i = coo_i2;
7502:     coo_j = coo_j2;
7503:   } else { /* no offproc values insertion */
7504:     ncoo = ncoo_d;
7505:     PetscCall(PetscMalloc2(ncoo, &coo_i, ncoo, &coo_j));

7507:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)C), &mmdata->sf));
7508:     PetscCall(PetscSFSetGraph(mmdata->sf, 0, 0, NULL, PETSC_OWN_POINTER, NULL, PETSC_OWN_POINTER));
7509:     PetscCall(PetscSFSetUp(mmdata->sf));
7510:   }
7511:   mmdata->hasoffproc = hasoffproc;

7513:   /* gather (i,j) of nonzeros inserted locally */
7514:   for (cp = 0, ncoo_d = 0; cp < mmdata->cp; cp++) {
7515:     Mat_SeqAIJ     *mm   = (Mat_SeqAIJ *)mp[cp]->data;
7516:     PetscInt       *coi  = coo_i + ncoo_d;
7517:     PetscInt       *coj  = coo_j + ncoo_d;
7518:     const PetscInt *jj   = mm->j;
7519:     const PetscInt *ii   = mm->i;
7520:     const PetscInt *cmap = cmapa[cp];
7521:     const PetscInt *rmap = rmapa[cp];
7522:     const PetscInt  mr   = mp[cp]->rmap->n;
7523:     const PetscInt  rs   = C->rmap->rstart;
7524:     const PetscInt  re   = C->rmap->rend;
7525:     const PetscInt  cs   = C->cmap->rstart;

7527:     if (mptmp[cp]) continue;
7528:     if (rmapt[cp] == 1) { /* consecutive rows */
7529:       /* fill coo_i */
7530:       for (i = 0; i < mr; i++) {
7531:         const PetscInt gr = i + rs;
7532:         for (j = ii[i]; j < ii[i + 1]; j++) coi[j] = gr;
7533:       }
7534:       /* fill coo_j */
7535:       if (!cmapt[cp]) { /* type-0, already global */
7536:         PetscCall(PetscArraycpy(coj, jj, mm->nz));
7537:       } else if (cmapt[cp] == 1) {                        /* type-1, local to global for consecutive columns of C */
7538:         for (j = 0; j < mm->nz; j++) coj[j] = jj[j] + cs; /* lid + col start */
7539:       } else {                                            /* type-2, local to global for sparse columns */
7540:         for (j = 0; j < mm->nz; j++) coj[j] = cmap[jj[j]];
7541:       }
7542:       ncoo_d += mm->nz;
7543:     } else if (rmapt[cp] == 2) { /* sparse rows */
7544:       for (i = 0; i < mr; i++) {
7545:         const PetscInt *jj = mm->j + ii[i];
7546:         const PetscInt  gr = rmap[i];
7547:         const PetscInt  nz = ii[i + 1] - ii[i];
7548:         if (gr >= rs && gr < re) { /* local rows */
7549:           for (j = ii[i]; j < ii[i + 1]; j++) *coi++ = gr;
7550:           if (!cmapt[cp]) { /* type-0, already global */
7551:             for (j = 0; j < nz; j++) *coj++ = jj[j];
7552:           } else if (cmapt[cp] == 1) { /* local to global for owned columns of C */
7553:             for (j = 0; j < nz; j++) *coj++ = jj[j] + cs;
7554:           } else { /* type-2, local to global for sparse columns */
7555:             for (j = 0; j < nz; j++) *coj++ = cmap[jj[j]];
7556:           }
7557:           ncoo_d += nz;
7558:         }
7559:       }
7560:     }
7561:   }
7562:   if (glob) PetscCall(ISRestoreIndices(glob, &globidx));
7563:   PetscCall(ISDestroy(&glob));
7564:   if (P_oth_l2g) PetscCall(ISLocalToGlobalMappingRestoreIndices(P_oth_l2g, &P_oth_idx));
7565:   PetscCall(ISLocalToGlobalMappingDestroy(&P_oth_l2g));
7566:   /* allocate an array to store all nonzeros (inserted locally or remotely) belonging to this proc */
7567:   PetscCall(PetscSFMalloc(mmdata->sf, mmdata->mtype, ncoo * sizeof(PetscScalar), (void **)&mmdata->coo_v));

7569:   /* set block sizes */
7570:   A = product->A;
7571:   P = product->B;
7572:   switch (ptype) {
7573:   case MATPRODUCT_PtAP:
7574:     PetscCall(MatSetBlockSizes(C, P->cmap->bs, P->cmap->bs));
7575:     break;
7576:   case MATPRODUCT_RARt:
7577:     PetscCall(MatSetBlockSizes(C, P->rmap->bs, P->rmap->bs));
7578:     break;
7579:   case MATPRODUCT_ABC:
7580:     PetscCall(MatSetBlockSizesFromMats(C, A, product->C));
7581:     break;
7582:   case MATPRODUCT_AB:
7583:     PetscCall(MatSetBlockSizesFromMats(C, A, P));
7584:     break;
7585:   case MATPRODUCT_AtB:
7586:     PetscCall(MatSetBlockSizes(C, A->cmap->bs, P->cmap->bs));
7587:     break;
7588:   case MATPRODUCT_ABt:
7589:     PetscCall(MatSetBlockSizes(C, A->rmap->bs, P->rmap->bs));
7590:     break;
7591:   default:
7592:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for ProductType %s", MatProductTypes[ptype]);
7593:   }

7595:   /* preallocate with COO data */
7596:   PetscCall(MatSetPreallocationCOO(C, ncoo, coo_i, coo_j));
7597:   PetscCall(PetscFree2(coo_i, coo_j));
7598:   PetscFunctionReturn(PETSC_SUCCESS);
7599: }

7601: PetscErrorCode MatProductSetFromOptions_MPIAIJBACKEND(Mat mat)
7602: {
7603:   Mat_Product *product = mat->product;
7604: #if defined(PETSC_HAVE_DEVICE)
7605:   PetscBool match  = PETSC_FALSE;
7606:   PetscBool usecpu = PETSC_FALSE;
7607: #else
7608:   PetscBool match = PETSC_TRUE;
7609: #endif

7611:   PetscFunctionBegin;
7612:   MatCheckProduct(mat, 1);
7613: #if defined(PETSC_HAVE_DEVICE)
7614:   if (!product->A->boundtocpu && !product->B->boundtocpu) PetscCall(PetscObjectTypeCompare((PetscObject)product->B, ((PetscObject)product->A)->type_name, &match));
7615:   if (match) { /* we can always fallback to the CPU if requested */
7616:     switch (product->type) {
7617:     case MATPRODUCT_AB:
7618:       if (product->api_user) {
7619:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatMatMult", "Mat");
7620:         PetscCall(PetscOptionsBool("-matmatmult_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
7621:         PetscOptionsEnd();
7622:       } else {
7623:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AB", "Mat");
7624:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
7625:         PetscOptionsEnd();
7626:       }
7627:       break;
7628:     case MATPRODUCT_AtB:
7629:       if (product->api_user) {
7630:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatTransposeMatMult", "Mat");
7631:         PetscCall(PetscOptionsBool("-mattransposematmult_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
7632:         PetscOptionsEnd();
7633:       } else {
7634:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AtB", "Mat");
7635:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
7636:         PetscOptionsEnd();
7637:       }
7638:       break;
7639:     case MATPRODUCT_PtAP:
7640:       if (product->api_user) {
7641:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatPtAP", "Mat");
7642:         PetscCall(PetscOptionsBool("-matptap_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
7643:         PetscOptionsEnd();
7644:       } else {
7645:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_PtAP", "Mat");
7646:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
7647:         PetscOptionsEnd();
7648:       }
7649:       break;
7650:     default:
7651:       break;
7652:     }
7653:     match = (PetscBool)!usecpu;
7654:   }
7655: #endif
7656:   if (match) {
7657:     switch (product->type) {
7658:     case MATPRODUCT_AB:
7659:     case MATPRODUCT_AtB:
7660:     case MATPRODUCT_PtAP:
7661:       mat->ops->productsymbolic = MatProductSymbolic_MPIAIJBACKEND;
7662:       break;
7663:     default:
7664:       break;
7665:     }
7666:   }
7667:   /* fallback to MPIAIJ ops */
7668:   if (!mat->ops->productsymbolic) PetscCall(MatProductSetFromOptions_MPIAIJ(mat));
7669:   PetscFunctionReturn(PETSC_SUCCESS);
7670: }

7672: /*
7673:    Produces a set of block column indices of the matrix row, one for each block represented in the original row

7675:    n - the number of block indices in cc[]
7676:    cc - the block indices (must be large enough to contain the indices)
7677: */
7678: static inline PetscErrorCode MatCollapseRow(Mat Amat, PetscInt row, PetscInt bs, PetscInt *n, PetscInt *cc)
7679: {
7680:   PetscInt        cnt = -1, nidx, j;
7681:   const PetscInt *idx;

7683:   PetscFunctionBegin;
7684:   PetscCall(MatGetRow(Amat, row, &nidx, &idx, NULL));
7685:   if (nidx) {
7686:     cnt     = 0;
7687:     cc[cnt] = idx[0] / bs;
7688:     for (j = 1; j < nidx; j++) {
7689:       if (cc[cnt] < idx[j] / bs) cc[++cnt] = idx[j] / bs;
7690:     }
7691:   }
7692:   PetscCall(MatRestoreRow(Amat, row, &nidx, &idx, NULL));
7693:   *n = cnt + 1;
7694:   PetscFunctionReturn(PETSC_SUCCESS);
7695: }

7697: /*
7698:     Produces a set of block column indices of the matrix block row, one for each block represented in the original set of rows

7700:     ncollapsed - the number of block indices
7701:     collapsed - the block indices (must be large enough to contain the indices)
7702: */
7703: static inline PetscErrorCode MatCollapseRows(Mat Amat, PetscInt start, PetscInt bs, PetscInt *w0, PetscInt *w1, PetscInt *w2, PetscInt *ncollapsed, PetscInt **collapsed)
7704: {
7705:   PetscInt i, nprev, *cprev = w0, ncur = 0, *ccur = w1, *merged = w2, *cprevtmp;

7707:   PetscFunctionBegin;
7708:   PetscCall(MatCollapseRow(Amat, start, bs, &nprev, cprev));
7709:   for (i = start + 1; i < start + bs; i++) {
7710:     PetscCall(MatCollapseRow(Amat, i, bs, &ncur, ccur));
7711:     PetscCall(PetscMergeIntArray(nprev, cprev, ncur, ccur, &nprev, &merged));
7712:     cprevtmp = cprev;
7713:     cprev    = merged;
7714:     merged   = cprevtmp;
7715:   }
7716:   *ncollapsed = nprev;
7717:   if (collapsed) *collapsed = cprev;
7718:   PetscFunctionReturn(PETSC_SUCCESS);
7719: }

7721: /*
7722:  MatCreateGraph_Simple_AIJ - create simple scalar matrix (graph) from potentially blocked matrix

7724:  Input Parameter:
7725:  . Amat - matrix
7726:  - symmetrize - make the result symmetric
7727:  + scale - scale with diagonal

7729:  Output Parameter:
7730:  . a_Gmat - output scalar graph >= 0

7732: */
7733: PETSC_INTERN PetscErrorCode MatCreateGraph_Simple_AIJ(Mat Amat, PetscBool symmetrize, PetscBool scale, PetscReal filter, PetscInt index_size, PetscInt index[], Mat *a_Gmat)
7734: {
7735:   PetscInt  Istart, Iend, Ii, jj, kk, ncols, nloc, NN, MM, bs;
7736:   MPI_Comm  comm;
7737:   Mat       Gmat;
7738:   PetscBool ismpiaij, isseqaij;
7739:   Mat       a, b, c;
7740:   MatType   jtype;

7742:   PetscFunctionBegin;
7743:   PetscCall(PetscObjectGetComm((PetscObject)Amat, &comm));
7744:   PetscCall(MatGetOwnershipRange(Amat, &Istart, &Iend));
7745:   PetscCall(MatGetSize(Amat, &MM, &NN));
7746:   PetscCall(MatGetBlockSize(Amat, &bs));
7747:   nloc = (Iend - Istart) / bs;

7749:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)Amat, MATSEQAIJ, &isseqaij));
7750:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)Amat, MATMPIAIJ, &ismpiaij));
7751:   PetscCheck(isseqaij || ismpiaij, comm, PETSC_ERR_USER, "Require (MPI)AIJ matrix type");

7753:   /* TODO GPU: these calls are potentially expensive if matrices are large and we want to use the GPU */
7754:   /* A solution consists in providing a new API, MatAIJGetCollapsedAIJ, and each class can provide a fast
7755:      implementation */
7756:   if (bs > 1) {
7757:     PetscCall(MatGetType(Amat, &jtype));
7758:     PetscCall(MatCreate(comm, &Gmat));
7759:     PetscCall(MatSetType(Gmat, jtype));
7760:     PetscCall(MatSetSizes(Gmat, nloc, nloc, PETSC_DETERMINE, PETSC_DETERMINE));
7761:     PetscCall(MatSetBlockSizes(Gmat, 1, 1));
7762:     if (isseqaij || ((Mat_MPIAIJ *)Amat->data)->garray) {
7763:       PetscInt  *d_nnz, *o_nnz;
7764:       MatScalar *aa, val, *AA;
7765:       PetscInt  *aj, *ai, *AJ, nc, nmax = 0;

7767:       if (isseqaij) {
7768:         a = Amat;
7769:         b = NULL;
7770:       } else {
7771:         Mat_MPIAIJ *d = (Mat_MPIAIJ *)Amat->data;
7772:         a             = d->A;
7773:         b             = d->B;
7774:       }
7775:       PetscCall(PetscInfo(Amat, "New bs>1 Graph. nloc=%" PetscInt_FMT "\n", nloc));
7776:       PetscCall(PetscMalloc2(nloc, &d_nnz, (isseqaij ? 0 : nloc), &o_nnz));
7777:       for (c = a, kk = 0; c && kk < 2; c = b, kk++) {
7778:         PetscInt       *nnz = (c == a) ? d_nnz : o_nnz;
7779:         const PetscInt *cols1, *cols2;

7781:         for (PetscInt brow = 0, nc1, nc2, ok = 1; brow < nloc * bs; brow += bs) { // block rows
7782:           PetscCall(MatGetRow(c, brow, &nc2, &cols2, NULL));
7783:           nnz[brow / bs] = nc2 / bs;
7784:           if (nc2 % bs) ok = 0;
7785:           if (nnz[brow / bs] > nmax) nmax = nnz[brow / bs];
7786:           for (PetscInt ii = 1; ii < bs; ii++) { // check for non-dense blocks
7787:             PetscCall(MatGetRow(c, brow + ii, &nc1, &cols1, NULL));
7788:             if (nc1 != nc2) ok = 0;
7789:             else {
7790:               for (PetscInt jj = 0; jj < nc1 && ok == 1; jj++) {
7791:                 if (cols1[jj] != cols2[jj]) ok = 0;
7792:                 if (cols1[jj] % bs != jj % bs) ok = 0;
7793:               }
7794:             }
7795:             PetscCall(MatRestoreRow(c, brow + ii, &nc1, &cols1, NULL));
7796:           }
7797:           PetscCall(MatRestoreRow(c, brow, &nc2, &cols2, NULL));
7798:           if (!ok) {
7799:             PetscCall(PetscFree2(d_nnz, o_nnz));
7800:             PetscCall(PetscInfo(Amat, "Found sparse blocks - revert to slow method\n"));
7801:             goto old_bs;
7802:           }
7803:         }
7804:       }
7805:       PetscCall(MatSeqAIJSetPreallocation(Gmat, 0, d_nnz));
7806:       PetscCall(MatMPIAIJSetPreallocation(Gmat, 0, d_nnz, 0, o_nnz));
7807:       PetscCall(PetscFree2(d_nnz, o_nnz));
7808:       PetscCall(PetscMalloc2(nmax, &AA, nmax, &AJ));
7809:       // diag
7810:       for (PetscInt brow = 0, n, grow; brow < nloc * bs; brow += bs) { // block rows
7811:         Mat_SeqAIJ *aseq = (Mat_SeqAIJ *)a->data;

7813:         ai = aseq->i;
7814:         n  = ai[brow + 1] - ai[brow];
7815:         aj = aseq->j + ai[brow];
7816:         for (PetscInt k = 0; k < n; k += bs) {   // block columns
7817:           AJ[k / bs] = aj[k] / bs + Istart / bs; // diag starts at (Istart,Istart)
7818:           val        = 0;
7819:           if (index_size == 0) {
7820:             for (PetscInt ii = 0; ii < bs; ii++) { // rows in block
7821:               aa = aseq->a + ai[brow + ii] + k;
7822:               for (PetscInt jj = 0; jj < bs; jj++) {    // columns in block
7823:                 val += PetscAbs(PetscRealPart(aa[jj])); // a sort of norm
7824:               }
7825:             }
7826:           } else {                                            // use (index,index) value if provided
7827:             for (PetscInt iii = 0; iii < index_size; iii++) { // rows in block
7828:               PetscInt ii = index[iii];
7829:               aa          = aseq->a + ai[brow + ii] + k;
7830:               for (PetscInt jjj = 0; jjj < index_size; jjj++) { // columns in block
7831:                 PetscInt jj = index[jjj];
7832:                 val += PetscAbs(PetscRealPart(aa[jj]));
7833:               }
7834:             }
7835:           }
7836:           PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs (%" PetscInt_FMT ") >= nmax (%" PetscInt_FMT ")", k / bs, nmax);
7837:           AA[k / bs] = val;
7838:         }
7839:         grow = Istart / bs + brow / bs;
7840:         PetscCall(MatSetValues(Gmat, 1, &grow, n / bs, AJ, AA, ADD_VALUES));
7841:       }
7842:       // off-diag
7843:       if (ismpiaij) {
7844:         Mat_MPIAIJ        *aij = (Mat_MPIAIJ *)Amat->data;
7845:         const PetscScalar *vals;
7846:         const PetscInt    *cols, *garray = aij->garray;

7848:         PetscCheck(garray, PETSC_COMM_SELF, PETSC_ERR_USER, "No garray ?");
7849:         for (PetscInt brow = 0, grow; brow < nloc * bs; brow += bs) { // block rows
7850:           PetscCall(MatGetRow(b, brow, &ncols, &cols, NULL));
7851:           for (PetscInt k = 0, cidx = 0; k < ncols; k += bs, cidx++) {
7852:             PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs >= nmax");
7853:             AA[k / bs] = 0;
7854:             AJ[cidx]   = garray[cols[k]] / bs;
7855:           }
7856:           nc = ncols / bs;
7857:           PetscCall(MatRestoreRow(b, brow, &ncols, &cols, NULL));
7858:           if (index_size == 0) {
7859:             for (PetscInt ii = 0; ii < bs; ii++) { // rows in block
7860:               PetscCall(MatGetRow(b, brow + ii, &ncols, &cols, &vals));
7861:               for (PetscInt k = 0; k < ncols; k += bs) {
7862:                 for (PetscInt jj = 0; jj < bs; jj++) { // cols in block
7863:                   PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs (%" PetscInt_FMT ") >= nmax (%" PetscInt_FMT ")", k / bs, nmax);
7864:                   AA[k / bs] += PetscAbs(PetscRealPart(vals[k + jj]));
7865:                 }
7866:               }
7867:               PetscCall(MatRestoreRow(b, brow + ii, &ncols, &cols, &vals));
7868:             }
7869:           } else {                                            // use (index,index) value if provided
7870:             for (PetscInt iii = 0; iii < index_size; iii++) { // rows in block
7871:               PetscInt ii = index[iii];
7872:               PetscCall(MatGetRow(b, brow + ii, &ncols, &cols, &vals));
7873:               for (PetscInt k = 0; k < ncols; k += bs) {
7874:                 for (PetscInt jjj = 0; jjj < index_size; jjj++) { // cols in block
7875:                   PetscInt jj = index[jjj];
7876:                   AA[k / bs] += PetscAbs(PetscRealPart(vals[k + jj]));
7877:                 }
7878:               }
7879:               PetscCall(MatRestoreRow(b, brow + ii, &ncols, &cols, &vals));
7880:             }
7881:           }
7882:           grow = Istart / bs + brow / bs;
7883:           PetscCall(MatSetValues(Gmat, 1, &grow, nc, AJ, AA, ADD_VALUES));
7884:         }
7885:       }
7886:       PetscCall(MatAssemblyBegin(Gmat, MAT_FINAL_ASSEMBLY));
7887:       PetscCall(MatAssemblyEnd(Gmat, MAT_FINAL_ASSEMBLY));
7888:       PetscCall(PetscFree2(AA, AJ));
7889:     } else {
7890:       const PetscScalar *vals;
7891:       const PetscInt    *idx;
7892:       PetscInt          *d_nnz, *o_nnz, *w0, *w1, *w2;
7893:     old_bs:
7894:       /*
7895:        Determine the preallocation needed for the scalar matrix derived from the vector matrix.
7896:        */
7897:       PetscCall(PetscInfo(Amat, "OLD bs>1 CreateGraph\n"));
7898:       PetscCall(PetscMalloc2(nloc, &d_nnz, (isseqaij ? 0 : nloc), &o_nnz));
7899:       if (isseqaij) {
7900:         PetscInt max_d_nnz;

7902:         /*
7903:          Determine exact preallocation count for (sequential) scalar matrix
7904:          */
7905:         PetscCall(MatSeqAIJGetMaxRowNonzeros(Amat, &max_d_nnz));
7906:         max_d_nnz = PetscMin(nloc, bs * max_d_nnz);
7907:         PetscCall(PetscMalloc3(max_d_nnz, &w0, max_d_nnz, &w1, max_d_nnz, &w2));
7908:         for (Ii = 0, jj = 0; Ii < Iend; Ii += bs, jj++) PetscCall(MatCollapseRows(Amat, Ii, bs, w0, w1, w2, &d_nnz[jj], NULL));
7909:         PetscCall(PetscFree3(w0, w1, w2));
7910:       } else if (ismpiaij) {
7911:         Mat             Daij, Oaij;
7912:         const PetscInt *garray;
7913:         PetscInt        max_d_nnz;

7915:         PetscCall(MatMPIAIJGetSeqAIJ(Amat, &Daij, &Oaij, &garray));
7916:         /*
7917:          Determine exact preallocation count for diagonal block portion of scalar matrix
7918:          */
7919:         PetscCall(MatSeqAIJGetMaxRowNonzeros(Daij, &max_d_nnz));
7920:         max_d_nnz = PetscMin(nloc, bs * max_d_nnz);
7921:         PetscCall(PetscMalloc3(max_d_nnz, &w0, max_d_nnz, &w1, max_d_nnz, &w2));
7922:         for (Ii = 0, jj = 0; Ii < Iend - Istart; Ii += bs, jj++) PetscCall(MatCollapseRows(Daij, Ii, bs, w0, w1, w2, &d_nnz[jj], NULL));
7923:         PetscCall(PetscFree3(w0, w1, w2));
7924:         /*
7925:          Over estimate (usually grossly over), preallocation count for off-diagonal portion of scalar matrix
7926:          */
7927:         for (Ii = 0, jj = 0; Ii < Iend - Istart; Ii += bs, jj++) {
7928:           o_nnz[jj] = 0;
7929:           for (kk = 0; kk < bs; kk++) { /* rows that get collapsed to a single row */
7930:             PetscCall(MatGetRow(Oaij, Ii + kk, &ncols, NULL, NULL));
7931:             o_nnz[jj] += ncols;
7932:             PetscCall(MatRestoreRow(Oaij, Ii + kk, &ncols, NULL, NULL));
7933:           }
7934:           if (o_nnz[jj] > (NN / bs - nloc)) o_nnz[jj] = NN / bs - nloc;
7935:         }
7936:       } else SETERRQ(comm, PETSC_ERR_USER, "Require AIJ matrix type");
7937:       /* get scalar copy (norms) of matrix */
7938:       PetscCall(MatSeqAIJSetPreallocation(Gmat, 0, d_nnz));
7939:       PetscCall(MatMPIAIJSetPreallocation(Gmat, 0, d_nnz, 0, o_nnz));
7940:       PetscCall(PetscFree2(d_nnz, o_nnz));
7941:       for (Ii = Istart; Ii < Iend; Ii++) {
7942:         PetscInt dest_row = Ii / bs;

7944:         PetscCall(MatGetRow(Amat, Ii, &ncols, &idx, &vals));
7945:         for (jj = 0; jj < ncols; jj++) {
7946:           PetscInt    dest_col = idx[jj] / bs;
7947:           PetscScalar sv       = PetscAbs(PetscRealPart(vals[jj]));

7949:           PetscCall(MatSetValues(Gmat, 1, &dest_row, 1, &dest_col, &sv, ADD_VALUES));
7950:         }
7951:         PetscCall(MatRestoreRow(Amat, Ii, &ncols, &idx, &vals));
7952:       }
7953:       PetscCall(MatAssemblyBegin(Gmat, MAT_FINAL_ASSEMBLY));
7954:       PetscCall(MatAssemblyEnd(Gmat, MAT_FINAL_ASSEMBLY));
7955:     }
7956:   } else {
7957:     if (symmetrize || filter >= 0 || scale) PetscCall(MatDuplicate(Amat, MAT_COPY_VALUES, &Gmat));
7958:     else {
7959:       Gmat = Amat;
7960:       PetscCall(PetscObjectReference((PetscObject)Gmat));
7961:     }
7962:     if (isseqaij) {
7963:       a = Gmat;
7964:       b = NULL;
7965:     } else {
7966:       Mat_MPIAIJ *d = (Mat_MPIAIJ *)Gmat->data;
7967:       a             = d->A;
7968:       b             = d->B;
7969:     }
7970:     if (filter >= 0 || scale) {
7971:       /* take absolute value of each entry */
7972:       for (c = a, kk = 0; c && kk < 2; c = b, kk++) {
7973:         MatInfo      info;
7974:         PetscScalar *avals;

7976:         PetscCall(MatGetInfo(c, MAT_LOCAL, &info));
7977:         PetscCall(MatSeqAIJGetArray(c, &avals));
7978:         for (int jj = 0; jj < info.nz_used; jj++) avals[jj] = PetscAbsScalar(avals[jj]);
7979:         PetscCall(MatSeqAIJRestoreArray(c, &avals));
7980:       }
7981:     }
7982:   }
7983:   if (symmetrize) {
7984:     PetscBool isset, issym;

7986:     PetscCall(MatIsSymmetricKnown(Amat, &isset, &issym));
7987:     if (!isset || !issym) {
7988:       Mat matTrans;

7990:       PetscCall(MatTranspose(Gmat, MAT_INITIAL_MATRIX, &matTrans));
7991:       PetscCall(MatAXPY(Gmat, 1.0, matTrans, Gmat->structurally_symmetric == PETSC_BOOL3_TRUE ? SAME_NONZERO_PATTERN : DIFFERENT_NONZERO_PATTERN));
7992:       PetscCall(MatDestroy(&matTrans));
7993:     }
7994:     PetscCall(MatSetOption(Gmat, MAT_SYMMETRIC, PETSC_TRUE));
7995:   } else if (Amat != Gmat) PetscCall(MatPropagateSymmetryOptions(Amat, Gmat));
7996:   if (scale) {
7997:     /* scale c for all diagonal values = 1 or -1 */
7998:     Vec diag;

8000:     PetscCall(MatCreateVecs(Gmat, &diag, NULL));
8001:     PetscCall(MatGetDiagonal(Gmat, diag));
8002:     PetscCall(VecReciprocal(diag));
8003:     PetscCall(VecSqrtAbs(diag));
8004:     PetscCall(MatDiagonalScale(Gmat, diag, diag));
8005:     PetscCall(VecDestroy(&diag));
8006:   }
8007:   PetscCall(MatViewFromOptions(Gmat, NULL, "-mat_graph_view"));
8008:   if (filter >= 0) {
8009:     PetscCall(MatFilter(Gmat, filter, PETSC_TRUE, PETSC_TRUE));
8010:     PetscCall(MatViewFromOptions(Gmat, NULL, "-mat_filter_graph_view"));
8011:   }
8012:   *a_Gmat = Gmat;
8013:   PetscFunctionReturn(PETSC_SUCCESS);
8014: }

8016: PETSC_INTERN PetscErrorCode MatGetCurrentMemType_MPIAIJ(Mat A, PetscMemType *memtype)
8017: {
8018:   Mat_MPIAIJ  *mpiaij = (Mat_MPIAIJ *)A->data;
8019:   PetscMemType mD = PETSC_MEMTYPE_HOST, mO = PETSC_MEMTYPE_HOST;

8021:   PetscFunctionBegin;
8022:   if (mpiaij->A) PetscCall(MatGetCurrentMemType(mpiaij->A, &mD));
8023:   if (mpiaij->B) PetscCall(MatGetCurrentMemType(mpiaij->B, &mO));
8024:   *memtype = (mD == mO) ? mD : PETSC_MEMTYPE_HOST;
8025:   PetscFunctionReturn(PETSC_SUCCESS);
8026: }

8028: /*
8029:     Special version for direct calls from Fortran
8030: */

8032: /* Change these macros so can be used in void function */
8033: /* Identical to PetscCallVoid, except it assigns to *_ierr */
8034: #undef PetscCall
8035: #define PetscCall(...) \
8036:   do { \
8037:     PetscErrorCode ierr_msv_mpiaij = __VA_ARGS__; \
8038:     if (PetscUnlikely(ierr_msv_mpiaij)) { \
8039:       *_ierr = PetscError(PETSC_COMM_SELF, __LINE__, PETSC_FUNCTION_NAME, __FILE__, ierr_msv_mpiaij, PETSC_ERROR_REPEAT, " "); \
8040:       return; \
8041:     } \
8042:   } while (0)

8044: #undef SETERRQ
8045: #define SETERRQ(comm, ierr, ...) \
8046:   do { \
8047:     *_ierr = PetscError(comm, __LINE__, PETSC_FUNCTION_NAME, __FILE__, ierr, PETSC_ERROR_INITIAL, __VA_ARGS__); \
8048:     return; \
8049:   } while (0)

8051: #if defined(PETSC_HAVE_FORTRAN_CAPS)
8052:   #define matsetvaluesmpiaij_ MATSETVALUESMPIAIJ
8053: #elif !defined(PETSC_HAVE_FORTRAN_UNDERSCORE)
8054:   #define matsetvaluesmpiaij_ matsetvaluesmpiaij
8055: #else
8056: #endif
8057: PETSC_EXTERN void matsetvaluesmpiaij_(Mat *mmat, PetscInt *mm, const PetscInt im[], PetscInt *mn, const PetscInt in[], const PetscScalar v[], InsertMode *maddv, PetscErrorCode *_ierr)
8058: {
8059:   Mat         mat = *mmat;
8060:   PetscInt    m = *mm, n = *mn;
8061:   InsertMode  addv = *maddv;
8062:   Mat_MPIAIJ *aij  = (Mat_MPIAIJ *)mat->data;
8063:   PetscScalar value;

8065:   MatCheckPreallocated(mat, 1);
8066:   if (mat->insertmode == NOT_SET_VALUES) mat->insertmode = addv;
8067:   else PetscCheck(mat->insertmode == addv, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Cannot mix add values and insert values");
8068:   {
8069:     PetscInt  i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
8070:     PetscInt  cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
8071:     PetscBool roworiented = aij->roworiented;

8073:     /* Some Variables required in the macro */
8074:     Mat         A     = aij->A;
8075:     Mat_SeqAIJ *a     = (Mat_SeqAIJ *)A->data;
8076:     PetscInt   *aimax = a->imax, *ai = a->i, *ailen = a->ilen, *aj = a->j;
8077:     MatScalar  *aa;
8078:     PetscBool   ignorezeroentries = ((a->ignorezeroentries && (addv == ADD_VALUES)) ? PETSC_TRUE : PETSC_FALSE);
8079:     Mat         B                 = aij->B;
8080:     Mat_SeqAIJ *b                 = (Mat_SeqAIJ *)B->data;
8081:     PetscInt   *bimax = b->imax, *bi = b->i, *bilen = b->ilen, *bj = b->j, bm = aij->B->rmap->n, am = aij->A->rmap->n;
8082:     MatScalar  *ba;
8083:     /* This variable below is only for the PETSC_HAVE_VIENNACL or PETSC_HAVE_CUDA cases, but we define it in all cases because we
8084:      * cannot use "#if defined" inside a macro. */
8085:     PETSC_UNUSED PetscBool inserted = PETSC_FALSE;

8087:     PetscInt  *rp1, *rp2, ii, nrow1, nrow2, _i, rmax1, rmax2, N, low1, high1, low2, high2, t, lastcol1, lastcol2;
8088:     PetscInt   nonew = a->nonew;
8089:     MatScalar *ap1, *ap2;

8091:     PetscFunctionBegin;
8092:     PetscCall(MatSeqAIJGetArray(A, &aa));
8093:     PetscCall(MatSeqAIJGetArray(B, &ba));
8094:     for (i = 0; i < m; i++) {
8095:       if (im[i] < 0) continue;
8096:       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);
8097:       if (im[i] >= rstart && im[i] < rend) {
8098:         row      = im[i] - rstart;
8099:         lastcol1 = -1;
8100:         rp1      = aj + ai[row];
8101:         ap1      = aa + ai[row];
8102:         rmax1    = aimax[row];
8103:         nrow1    = ailen[row];
8104:         low1     = 0;
8105:         high1    = nrow1;
8106:         lastcol2 = -1;
8107:         rp2      = bj + bi[row];
8108:         ap2      = ba + bi[row];
8109:         rmax2    = bimax[row];
8110:         nrow2    = bilen[row];
8111:         low2     = 0;
8112:         high2    = nrow2;

8114:         for (j = 0; j < n; j++) {
8115:           if (roworiented) value = v[i * n + j];
8116:           else value = v[i + j * m];
8117:           if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES) && im[i] != in[j]) continue;
8118:           if (in[j] >= cstart && in[j] < cend) {
8119:             col = in[j] - cstart;
8120:             MatSetValues_SeqAIJ_A_Private(row, col, value, addv, im[i], in[j]);
8121:           } else if (in[j] < 0) continue;
8122:           else if (PetscUnlikelyDebug(in[j] >= mat->cmap->N)) {
8123:             SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column too large: col %" PetscInt_FMT " max %" PetscInt_FMT, in[j], mat->cmap->N - 1);
8124:           } else {
8125:             if (mat->was_assembled) {
8126:               if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
8127: #if defined(PETSC_USE_CTABLE)
8128:               PetscCall(PetscHMapIGetWithDefault(aij->colmap, in[j] + 1, 0, &col));
8129:               col--;
8130: #else
8131:               col = aij->colmap[in[j]] - 1;
8132: #endif
8133:               if (col < 0 && !((Mat_SeqAIJ *)aij->A->data)->nonew) {
8134:                 PetscCall(MatDisAssemble_MPIAIJ(mat, PETSC_FALSE));
8135:                 col = in[j];
8136:                 /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
8137:                 B        = aij->B;
8138:                 b        = (Mat_SeqAIJ *)B->data;
8139:                 bimax    = b->imax;
8140:                 bi       = b->i;
8141:                 bilen    = b->ilen;
8142:                 bj       = b->j;
8143:                 rp2      = bj + bi[row];
8144:                 ap2      = ba + bi[row];
8145:                 rmax2    = bimax[row];
8146:                 nrow2    = bilen[row];
8147:                 low2     = 0;
8148:                 high2    = nrow2;
8149:                 bm       = aij->B->rmap->n;
8150:                 ba       = b->a;
8151:                 inserted = PETSC_FALSE;
8152:               }
8153:             } else col = in[j];
8154:             MatSetValues_SeqAIJ_B_Private(row, col, value, addv, im[i], in[j]);
8155:           }
8156:         }
8157:       } else if (!aij->donotstash) {
8158:         if (roworiented) {
8159:           PetscCall(MatStashValuesRow_Private(&mat->stash, im[i], n, in, v + i * n, (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
8160:         } else {
8161:           PetscCall(MatStashValuesCol_Private(&mat->stash, im[i], n, in, v + i, m, (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
8162:         }
8163:       }
8164:     }
8165:     PetscCall(MatSeqAIJRestoreArray(A, &aa));
8166:     PetscCall(MatSeqAIJRestoreArray(B, &ba));
8167:   }
8168:   PetscFunctionReturnVoid();
8169: }

8171: /* Undefining these here since they were redefined from their original definition above! No
8172:  * other PETSc functions should be defined past this point, as it is impossible to recover the
8173:  * original definitions */
8174: #undef PetscCall
8175: #undef SETERRQ