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: PetscErrorCode MatDestroy_MPIAIJ(Mat mat)
 10: {
 11:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

 13:   PetscFunctionBegin;
 14:   PetscCall(PetscLogObjectState((PetscObject)mat, "Rows=%" PetscInt_FMT ", Cols=%" PetscInt_FMT, mat->rmap->N, mat->cmap->N));
 15:   PetscCall(MatStashDestroy_Private(&mat->stash));
 16:   PetscCall(VecDestroy(&aij->diag));
 17:   PetscCall(MatDestroy(&aij->A));
 18:   PetscCall(MatDestroy(&aij->B));
 19: #if defined(PETSC_USE_CTABLE)
 20:   PetscCall(PetscHMapIDestroy(&aij->colmap));
 21: #else
 22:   PetscCall(PetscFree(aij->colmap));
 23: #endif
 24:   PetscCall(PetscFree(aij->garray));
 25:   PetscCall(VecDestroy(&aij->lvec));
 26:   PetscCall(VecScatterDestroy(&aij->Mvctx));
 27:   PetscCall(PetscFree2(aij->rowvalues, aij->rowindices));
 28:   PetscCall(PetscFree(aij->ld));

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

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

 35:   PetscCall(PetscObjectChangeTypeName((PetscObject)mat, NULL));
 36:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatStoreValues_C", NULL));
 37:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatRetrieveValues_C", NULL));
 38:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatIsTranspose_C", NULL));
 39:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetPreallocation_C", NULL));
 40:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatResetPreallocation_C", NULL));
 41:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetPreallocationCSR_C", NULL));
 42:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatDiagonalScaleLocal_C", NULL));
 43:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpibaij_C", NULL));
 44:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpisbaij_C", NULL));
 45: #if defined(PETSC_HAVE_CUDA)
 46:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijcusparse_C", NULL));
 47: #endif
 48: #if defined(PETSC_HAVE_HIP)
 49:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijhipsparse_C", NULL));
 50: #endif
 51: #if defined(PETSC_HAVE_KOKKOS_KERNELS)
 52:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijkokkos_C", NULL));
 53: #endif
 54:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpidense_C", NULL));
 55: #if defined(PETSC_HAVE_ELEMENTAL)
 56:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_elemental_C", NULL));
 57: #endif
 58: #if defined(PETSC_HAVE_SCALAPACK)
 59:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_scalapack_C", NULL));
 60: #endif
 61: #if defined(PETSC_HAVE_HYPRE)
 62:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_hypre_C", NULL));
 63:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_transpose_mpiaij_mpiaij_C", NULL));
 64: #endif
 65:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_is_C", NULL));
 66:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_is_mpiaij_C", NULL));
 67:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_mpiaij_mpiaij_C", NULL));
 68:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetUseScalableIncreaseOverlap_C", NULL));
 69:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijperm_C", NULL));
 70:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijsell_C", NULL));
 71: #if defined(PETSC_HAVE_MKL_SPARSE)
 72:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijmkl_C", NULL));
 73: #endif
 74:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijcrl_C", NULL));
 75:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_is_C", NULL));
 76:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpisell_C", NULL));
 77:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatSetPreallocationCOO_C", NULL));
 78:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatSetValuesCOO_C", NULL));
 79:   PetscFunctionReturn(PETSC_SUCCESS);
 80: }

 82: /* defines MatSetValues_MPI_Hash(), MatAssemblyBegin_MPI_Hash(), and  MatAssemblyEnd_MPI_Hash() */
 83: #define TYPE AIJ
 84: #define TYPE_AIJ
 85: #include "../src/mat/impls/aij/mpi/mpihashmat.h"
 86: #undef TYPE
 87: #undef TYPE_AIJ

 89: static PetscErrorCode MatGetRowIJ_MPIAIJ(Mat A, PetscInt oshift, PetscBool symmetric, PetscBool inodecompressed, PetscInt *m, const PetscInt *ia[], const PetscInt *ja[], PetscBool *done)
 90: {
 91:   Mat B;

 93:   PetscFunctionBegin;
 94:   PetscCall(MatMPIAIJGetLocalMat(A, MAT_INITIAL_MATRIX, &B));
 95:   PetscCall(PetscObjectCompose((PetscObject)A, "MatGetRowIJ_MPIAIJ", (PetscObject)B));
 96:   PetscCall(MatGetRowIJ(B, oshift, symmetric, inodecompressed, m, ia, ja, done));
 97:   PetscCall(MatDestroy(&B));
 98:   PetscFunctionReturn(PETSC_SUCCESS);
 99: }

101: static PetscErrorCode MatRestoreRowIJ_MPIAIJ(Mat A, PetscInt oshift, PetscBool symmetric, PetscBool inodecompressed, PetscInt *m, const PetscInt *ia[], const PetscInt *ja[], PetscBool *done)
102: {
103:   Mat B;

105:   PetscFunctionBegin;
106:   PetscCall(PetscObjectQuery((PetscObject)A, "MatGetRowIJ_MPIAIJ", (PetscObject *)&B));
107:   PetscCall(MatRestoreRowIJ(B, oshift, symmetric, inodecompressed, m, ia, ja, done));
108:   PetscCall(PetscObjectCompose((PetscObject)A, "MatGetRowIJ_MPIAIJ", NULL));
109:   PetscFunctionReturn(PETSC_SUCCESS);
110: }

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

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

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

124:   Developer Note:
125:   Level: beginner

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

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

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

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

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

145:   Level: beginner

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

150: static PetscErrorCode MatBindToCPU_MPIAIJ(Mat A, PetscBool flg)
151: {
152:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

154:   PetscFunctionBegin;
155: #if defined(PETSC_HAVE_CUDA) || defined(PETSC_HAVE_HIP) || defined(PETSC_HAVE_VIENNACL)
156:   A->boundtocpu = flg;
157: #endif
158:   if (a->A) PetscCall(MatBindToCPU(a->A, flg));
159:   if (a->B) PetscCall(MatBindToCPU(a->B, flg));

161:   /* In addition to binding the diagonal and off-diagonal matrices, bind the local vectors used for matrix-vector products.
162:    * This maybe seems a little odd for a MatBindToCPU() call to do, but it makes no sense for the binding of these vectors
163:    * to differ from the parent matrix. */
164:   if (a->lvec) PetscCall(VecBindToCPU(a->lvec, flg));
165:   if (a->diag) PetscCall(VecBindToCPU(a->diag, flg));

167:   PetscFunctionReturn(PETSC_SUCCESS);
168: }

170: static PetscErrorCode MatSetBlockSizes_MPIAIJ(Mat M, PetscInt rbs, PetscInt cbs)
171: {
172:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)M->data;

174:   PetscFunctionBegin;
175:   if (mat->A) {
176:     PetscCall(MatSetBlockSizes(mat->A, rbs, cbs));
177:     PetscCall(MatSetBlockSizes(mat->B, rbs, 1));
178:   }
179:   PetscFunctionReturn(PETSC_SUCCESS);
180: }

182: static PetscErrorCode MatFindNonzeroRows_MPIAIJ(Mat M, IS *keptrows)
183: {
184:   Mat_MPIAIJ      *mat = (Mat_MPIAIJ *)M->data;
185:   Mat_SeqAIJ      *a   = (Mat_SeqAIJ *)mat->A->data;
186:   Mat_SeqAIJ      *b   = (Mat_SeqAIJ *)mat->B->data;
187:   const PetscInt  *ia, *ib;
188:   const MatScalar *aa, *bb, *aav, *bav;
189:   PetscInt         na, nb, i, j, *rows, cnt = 0, n0rows;
190:   PetscInt         m = M->rmap->n, rstart = M->rmap->rstart;

192:   PetscFunctionBegin;
193:   *keptrows = NULL;

195:   ia = a->i;
196:   ib = b->i;
197:   PetscCall(MatSeqAIJGetArrayRead(mat->A, &aav));
198:   PetscCall(MatSeqAIJGetArrayRead(mat->B, &bav));
199:   for (i = 0; i < m; i++) {
200:     na = ia[i + 1] - ia[i];
201:     nb = ib[i + 1] - ib[i];
202:     if (!na && !nb) {
203:       cnt++;
204:       goto ok1;
205:     }
206:     aa = aav + ia[i];
207:     for (j = 0; j < na; j++) {
208:       if (aa[j] != 0.0) goto ok1;
209:     }
210:     bb = bav ? bav + ib[i] : NULL;
211:     for (j = 0; j < nb; j++) {
212:       if (bb[j] != 0.0) goto ok1;
213:     }
214:     cnt++;
215:   ok1:;
216:   }
217:   PetscCall(MPIU_Allreduce(&cnt, &n0rows, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)M)));
218:   if (!n0rows) {
219:     PetscCall(MatSeqAIJRestoreArrayRead(mat->A, &aav));
220:     PetscCall(MatSeqAIJRestoreArrayRead(mat->B, &bav));
221:     PetscFunctionReturn(PETSC_SUCCESS);
222:   }
223:   PetscCall(PetscMalloc1(M->rmap->n - cnt, &rows));
224:   cnt = 0;
225:   for (i = 0; i < m; i++) {
226:     na = ia[i + 1] - ia[i];
227:     nb = ib[i + 1] - ib[i];
228:     if (!na && !nb) continue;
229:     aa = aav + ia[i];
230:     for (j = 0; j < na; j++) {
231:       if (aa[j] != 0.0) {
232:         rows[cnt++] = rstart + i;
233:         goto ok2;
234:       }
235:     }
236:     bb = bav ? bav + ib[i] : NULL;
237:     for (j = 0; j < nb; j++) {
238:       if (bb[j] != 0.0) {
239:         rows[cnt++] = rstart + i;
240:         goto ok2;
241:       }
242:     }
243:   ok2:;
244:   }
245:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)M), cnt, rows, PETSC_OWN_POINTER, keptrows));
246:   PetscCall(MatSeqAIJRestoreArrayRead(mat->A, &aav));
247:   PetscCall(MatSeqAIJRestoreArrayRead(mat->B, &bav));
248:   PetscFunctionReturn(PETSC_SUCCESS);
249: }

251: static PetscErrorCode MatDiagonalSet_MPIAIJ(Mat Y, Vec D, InsertMode is)
252: {
253:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)Y->data;
254:   PetscBool   cong;

256:   PetscFunctionBegin;
257:   PetscCall(MatHasCongruentLayouts(Y, &cong));
258:   if (Y->assembled && cong) {
259:     PetscCall(MatDiagonalSet(aij->A, D, is));
260:   } else {
261:     PetscCall(MatDiagonalSet_Default(Y, D, is));
262:   }
263:   PetscFunctionReturn(PETSC_SUCCESS);
264: }

266: static PetscErrorCode MatFindZeroDiagonals_MPIAIJ(Mat M, IS *zrows)
267: {
268:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)M->data;
269:   PetscInt    i, rstart, nrows, *rows;

271:   PetscFunctionBegin;
272:   *zrows = NULL;
273:   PetscCall(MatFindZeroDiagonals_SeqAIJ_Private(aij->A, &nrows, &rows));
274:   PetscCall(MatGetOwnershipRange(M, &rstart, NULL));
275:   for (i = 0; i < nrows; i++) rows[i] += rstart;
276:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)M), nrows, rows, PETSC_OWN_POINTER, zrows));
277:   PetscFunctionReturn(PETSC_SUCCESS);
278: }

280: static PetscErrorCode MatGetColumnReductions_MPIAIJ(Mat A, PetscInt type, PetscReal *reductions)
281: {
282:   Mat_MPIAIJ        *aij = (Mat_MPIAIJ *)A->data;
283:   PetscInt           i, m, n, *garray = aij->garray;
284:   Mat_SeqAIJ        *a_aij = (Mat_SeqAIJ *)aij->A->data;
285:   Mat_SeqAIJ        *b_aij = (Mat_SeqAIJ *)aij->B->data;
286:   PetscReal         *work;
287:   const PetscScalar *dummy;

289:   PetscFunctionBegin;
290:   PetscCall(MatGetSize(A, &m, &n));
291:   PetscCall(PetscCalloc1(n, &work));
292:   PetscCall(MatSeqAIJGetArrayRead(aij->A, &dummy));
293:   PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &dummy));
294:   PetscCall(MatSeqAIJGetArrayRead(aij->B, &dummy));
295:   PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &dummy));
296:   if (type == NORM_2) {
297:     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]);
298:     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]);
299:   } else if (type == NORM_1) {
300:     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]);
301:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i]);
302:   } else if (type == NORM_INFINITY) {
303:     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]]);
304:     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]]]);
305:   } else if (type == REDUCTION_SUM_REALPART || type == REDUCTION_MEAN_REALPART) {
306:     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]);
307:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] += PetscRealPart(b_aij->a[i]);
308:   } else if (type == REDUCTION_SUM_IMAGINARYPART || type == REDUCTION_MEAN_IMAGINARYPART) {
309:     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]);
310:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] += PetscImaginaryPart(b_aij->a[i]);
311:   } else SETERRQ(PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONG, "Unknown reduction type");
312:   if (type == NORM_INFINITY) {
313:     PetscCall(MPIU_Allreduce(work, reductions, n, MPIU_REAL, MPIU_MAX, PetscObjectComm((PetscObject)A)));
314:   } else {
315:     PetscCall(MPIU_Allreduce(work, reductions, n, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)A)));
316:   }
317:   PetscCall(PetscFree(work));
318:   if (type == NORM_2) {
319:     for (i = 0; i < n; i++) reductions[i] = PetscSqrtReal(reductions[i]);
320:   } else if (type == REDUCTION_MEAN_REALPART || type == REDUCTION_MEAN_IMAGINARYPART) {
321:     for (i = 0; i < n; i++) reductions[i] /= m;
322:   }
323:   PetscFunctionReturn(PETSC_SUCCESS);
324: }

326: static PetscErrorCode MatFindOffBlockDiagonalEntries_MPIAIJ(Mat A, IS *is)
327: {
328:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)A->data;
329:   IS              sis, gis;
330:   const PetscInt *isis, *igis;
331:   PetscInt        n, *iis, nsis, ngis, rstart, i;

333:   PetscFunctionBegin;
334:   PetscCall(MatFindOffBlockDiagonalEntries(a->A, &sis));
335:   PetscCall(MatFindNonzeroRows(a->B, &gis));
336:   PetscCall(ISGetSize(gis, &ngis));
337:   PetscCall(ISGetSize(sis, &nsis));
338:   PetscCall(ISGetIndices(sis, &isis));
339:   PetscCall(ISGetIndices(gis, &igis));

341:   PetscCall(PetscMalloc1(ngis + nsis, &iis));
342:   PetscCall(PetscArraycpy(iis, igis, ngis));
343:   PetscCall(PetscArraycpy(iis + ngis, isis, nsis));
344:   n = ngis + nsis;
345:   PetscCall(PetscSortRemoveDupsInt(&n, iis));
346:   PetscCall(MatGetOwnershipRange(A, &rstart, NULL));
347:   for (i = 0; i < n; i++) iis[i] += rstart;
348:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)A), n, iis, PETSC_OWN_POINTER, is));

350:   PetscCall(ISRestoreIndices(sis, &isis));
351:   PetscCall(ISRestoreIndices(gis, &igis));
352:   PetscCall(ISDestroy(&sis));
353:   PetscCall(ISDestroy(&gis));
354:   PetscFunctionReturn(PETSC_SUCCESS);
355: }

357: /*
358:   Local utility routine that creates a mapping from the global column
359: number to the local number in the off-diagonal part of the local
360: storage of the matrix.  When PETSC_USE_CTABLE is used this is scalable at
361: a slightly higher hash table cost; without it it is not scalable (each processor
362: has an order N integer array but is fast to access.
363: */
364: PetscErrorCode MatCreateColmap_MPIAIJ_Private(Mat mat)
365: {
366:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
367:   PetscInt    n   = aij->B->cmap->n, i;

369:   PetscFunctionBegin;
370:   PetscCheck(!n || aij->garray, PETSC_COMM_SELF, PETSC_ERR_PLIB, "MPIAIJ Matrix was assembled but is missing garray");
371: #if defined(PETSC_USE_CTABLE)
372:   PetscCall(PetscHMapICreateWithSize(n, &aij->colmap));
373:   for (i = 0; i < n; i++) PetscCall(PetscHMapISet(aij->colmap, aij->garray[i] + 1, i + 1));
374: #else
375:   PetscCall(PetscCalloc1(mat->cmap->N + 1, &aij->colmap));
376:   for (i = 0; i < n; i++) aij->colmap[aij->garray[i]] = i + 1;
377: #endif
378:   PetscFunctionReturn(PETSC_SUCCESS);
379: }

381: #define MatSetValues_SeqAIJ_A_Private(row, col, value, addv, orow, ocol) \
382:   do { \
383:     if (col <= lastcol1) low1 = 0; \
384:     else high1 = nrow1; \
385:     lastcol1 = col; \
386:     while (high1 - low1 > 5) { \
387:       t = (low1 + high1) / 2; \
388:       if (rp1[t] > col) high1 = t; \
389:       else low1 = t; \
390:     } \
391:     for (_i = low1; _i < high1; _i++) { \
392:       if (rp1[_i] > col) break; \
393:       if (rp1[_i] == col) { \
394:         if (addv == ADD_VALUES) { \
395:           ap1[_i] += value; \
396:           /* Not sure LogFlops will slow dow the code or not */ \
397:           (void)PetscLogFlops(1.0); \
398:         } else ap1[_i] = value; \
399:         goto a_noinsert; \
400:       } \
401:     } \
402:     if (value == 0.0 && ignorezeroentries && row != col) { \
403:       low1  = 0; \
404:       high1 = nrow1; \
405:       goto a_noinsert; \
406:     } \
407:     if (nonew == 1) { \
408:       low1  = 0; \
409:       high1 = nrow1; \
410:       goto a_noinsert; \
411:     } \
412:     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); \
413:     MatSeqXAIJReallocateAIJ(A, am, 1, nrow1, row, col, rmax1, aa, ai, aj, rp1, ap1, aimax, nonew, MatScalar); \
414:     N = nrow1++ - 1; \
415:     a->nz++; \
416:     high1++; \
417:     /* shift up all the later entries in this row */ \
418:     PetscCall(PetscArraymove(rp1 + _i + 1, rp1 + _i, N - _i + 1)); \
419:     PetscCall(PetscArraymove(ap1 + _i + 1, ap1 + _i, N - _i + 1)); \
420:     rp1[_i] = col; \
421:     ap1[_i] = value; \
422:     A->nonzerostate++; \
423:   a_noinsert:; \
424:     ailen[row] = nrow1; \
425:   } while (0)

427: #define MatSetValues_SeqAIJ_B_Private(row, col, value, addv, orow, ocol) \
428:   do { \
429:     if (col <= lastcol2) low2 = 0; \
430:     else high2 = nrow2; \
431:     lastcol2 = col; \
432:     while (high2 - low2 > 5) { \
433:       t = (low2 + high2) / 2; \
434:       if (rp2[t] > col) high2 = t; \
435:       else low2 = t; \
436:     } \
437:     for (_i = low2; _i < high2; _i++) { \
438:       if (rp2[_i] > col) break; \
439:       if (rp2[_i] == col) { \
440:         if (addv == ADD_VALUES) { \
441:           ap2[_i] += value; \
442:           (void)PetscLogFlops(1.0); \
443:         } else ap2[_i] = value; \
444:         goto b_noinsert; \
445:       } \
446:     } \
447:     if (value == 0.0 && ignorezeroentries) { \
448:       low2  = 0; \
449:       high2 = nrow2; \
450:       goto b_noinsert; \
451:     } \
452:     if (nonew == 1) { \
453:       low2  = 0; \
454:       high2 = nrow2; \
455:       goto b_noinsert; \
456:     } \
457:     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); \
458:     MatSeqXAIJReallocateAIJ(B, bm, 1, nrow2, row, col, rmax2, ba, bi, bj, rp2, ap2, bimax, nonew, MatScalar); \
459:     N = nrow2++ - 1; \
460:     b->nz++; \
461:     high2++; \
462:     /* shift up all the later entries in this row */ \
463:     PetscCall(PetscArraymove(rp2 + _i + 1, rp2 + _i, N - _i + 1)); \
464:     PetscCall(PetscArraymove(ap2 + _i + 1, ap2 + _i, N - _i + 1)); \
465:     rp2[_i] = col; \
466:     ap2[_i] = value; \
467:     B->nonzerostate++; \
468:   b_noinsert:; \
469:     bilen[row] = nrow2; \
470:   } while (0)

472: static PetscErrorCode MatSetValuesRow_MPIAIJ(Mat A, PetscInt row, const PetscScalar v[])
473: {
474:   Mat_MPIAIJ  *mat = (Mat_MPIAIJ *)A->data;
475:   Mat_SeqAIJ  *a = (Mat_SeqAIJ *)mat->A->data, *b = (Mat_SeqAIJ *)mat->B->data;
476:   PetscInt     l, *garray                         = mat->garray, diag;
477:   PetscScalar *aa, *ba;

479:   PetscFunctionBegin;
480:   /* code only works for square matrices A */

482:   /* find size of row to the left of the diagonal part */
483:   PetscCall(MatGetOwnershipRange(A, &diag, NULL));
484:   row = row - diag;
485:   for (l = 0; l < b->i[row + 1] - b->i[row]; l++) {
486:     if (garray[b->j[b->i[row] + l]] > diag) break;
487:   }
488:   if (l) {
489:     PetscCall(MatSeqAIJGetArray(mat->B, &ba));
490:     PetscCall(PetscArraycpy(ba + b->i[row], v, l));
491:     PetscCall(MatSeqAIJRestoreArray(mat->B, &ba));
492:   }

494:   /* diagonal part */
495:   if (a->i[row + 1] - a->i[row]) {
496:     PetscCall(MatSeqAIJGetArray(mat->A, &aa));
497:     PetscCall(PetscArraycpy(aa + a->i[row], v + l, (a->i[row + 1] - a->i[row])));
498:     PetscCall(MatSeqAIJRestoreArray(mat->A, &aa));
499:   }

501:   /* right of diagonal part */
502:   if (b->i[row + 1] - b->i[row] - l) {
503:     PetscCall(MatSeqAIJGetArray(mat->B, &ba));
504:     PetscCall(PetscArraycpy(ba + b->i[row] + l, v + l + a->i[row + 1] - a->i[row], b->i[row + 1] - b->i[row] - l));
505:     PetscCall(MatSeqAIJRestoreArray(mat->B, &ba));
506:   }
507:   PetscFunctionReturn(PETSC_SUCCESS);
508: }

510: PetscErrorCode MatSetValues_MPIAIJ(Mat mat, PetscInt m, const PetscInt im[], PetscInt n, const PetscInt in[], const PetscScalar v[], InsertMode addv)
511: {
512:   Mat_MPIAIJ *aij   = (Mat_MPIAIJ *)mat->data;
513:   PetscScalar value = 0.0;
514:   PetscInt    i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
515:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
516:   PetscBool   roworiented = aij->roworiented;

518:   /* Some Variables required in the macro */
519:   Mat         A     = aij->A;
520:   Mat_SeqAIJ *a     = (Mat_SeqAIJ *)A->data;
521:   PetscInt   *aimax = a->imax, *ai = a->i, *ailen = a->ilen, *aj = a->j;
522:   PetscBool   ignorezeroentries = a->ignorezeroentries;
523:   Mat         B                 = aij->B;
524:   Mat_SeqAIJ *b                 = (Mat_SeqAIJ *)B->data;
525:   PetscInt   *bimax = b->imax, *bi = b->i, *bilen = b->ilen, *bj = b->j, bm = aij->B->rmap->n, am = aij->A->rmap->n;
526:   MatScalar  *aa, *ba;
527:   PetscInt   *rp1, *rp2, ii, nrow1, nrow2, _i, rmax1, rmax2, N, low1, high1, low2, high2, t, lastcol1, lastcol2;
528:   PetscInt    nonew;
529:   MatScalar  *ap1, *ap2;

531:   PetscFunctionBegin;
532:   PetscCall(MatSeqAIJGetArray(A, &aa));
533:   PetscCall(MatSeqAIJGetArray(B, &ba));
534:   for (i = 0; i < m; i++) {
535:     if (im[i] < 0) continue;
536:     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);
537:     if (im[i] >= rstart && im[i] < rend) {
538:       row      = im[i] - rstart;
539:       lastcol1 = -1;
540:       rp1      = aj ? aj + ai[row] : NULL;
541:       ap1      = aa ? aa + ai[row] : NULL;
542:       rmax1    = aimax[row];
543:       nrow1    = ailen[row];
544:       low1     = 0;
545:       high1    = nrow1;
546:       lastcol2 = -1;
547:       rp2      = bj ? bj + bi[row] : NULL;
548:       ap2      = ba ? ba + bi[row] : NULL;
549:       rmax2    = bimax[row];
550:       nrow2    = bilen[row];
551:       low2     = 0;
552:       high2    = nrow2;

554:       for (j = 0; j < n; j++) {
555:         if (v) value = roworiented ? v[i * n + j] : v[i + j * m];
556:         if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES) && im[i] != in[j]) continue;
557:         if (in[j] >= cstart && in[j] < cend) {
558:           col   = in[j] - cstart;
559:           nonew = a->nonew;
560:           MatSetValues_SeqAIJ_A_Private(row, col, value, addv, im[i], in[j]);
561:         } else if (in[j] < 0) {
562:           continue;
563:         } else {
564:           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);
565:           if (mat->was_assembled) {
566:             if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
567: #if defined(PETSC_USE_CTABLE)
568:             PetscCall(PetscHMapIGetWithDefault(aij->colmap, in[j] + 1, 0, &col)); /* map global col ids to local ones */
569:             col--;
570: #else
571:             col = aij->colmap[in[j]] - 1;
572: #endif
573:             if (col < 0 && !((Mat_SeqAIJ *)(aij->B->data))->nonew) { /* col < 0 means in[j] is a new col for B */
574:               PetscCall(MatDisAssemble_MPIAIJ(mat));                 /* Change aij->B from reduced/local format to expanded/global format */
575:               col = in[j];
576:               /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
577:               B     = aij->B;
578:               b     = (Mat_SeqAIJ *)B->data;
579:               bimax = b->imax;
580:               bi    = b->i;
581:               bilen = b->ilen;
582:               bj    = b->j;
583:               ba    = b->a;
584:               rp2   = bj + bi[row];
585:               ap2   = ba + bi[row];
586:               rmax2 = bimax[row];
587:               nrow2 = bilen[row];
588:               low2  = 0;
589:               high2 = nrow2;
590:               bm    = aij->B->rmap->n;
591:               ba    = b->a;
592:             } else if (col < 0 && !(ignorezeroentries && value == 0.0)) {
593:               if (1 == ((Mat_SeqAIJ *)(aij->B->data))->nonew) {
594:                 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]));
595:               } else SETERRQ(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]);
596:             }
597:           } else col = in[j];
598:           nonew = b->nonew;
599:           MatSetValues_SeqAIJ_B_Private(row, col, value, addv, im[i], in[j]);
600:         }
601:       }
602:     } else {
603:       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]);
604:       if (!aij->donotstash) {
605:         mat->assembled = PETSC_FALSE;
606:         if (roworiented) {
607:           PetscCall(MatStashValuesRow_Private(&mat->stash, im[i], n, in, v ? v + i * n : NULL, (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
608:         } else {
609:           PetscCall(MatStashValuesCol_Private(&mat->stash, im[i], n, in, v ? v + i : NULL, m, (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
610:         }
611:       }
612:     }
613:   }
614:   PetscCall(MatSeqAIJRestoreArray(A, &aa)); /* aa, bb might have been free'd due to reallocation above. But we don't access them here */
615:   PetscCall(MatSeqAIJRestoreArray(B, &ba));
616:   PetscFunctionReturn(PETSC_SUCCESS);
617: }

619: /*
620:     This function sets the j and ilen arrays (of the diagonal and off-diagonal part) of an MPIAIJ-matrix.
621:     The values in mat_i have to be sorted and the values in mat_j have to be sorted for each row (CSR-like).
622:     No off-processor parts off the matrix are allowed here and mat->was_assembled has to be PETSC_FALSE.
623: */
624: PetscErrorCode MatSetValues_MPIAIJ_CopyFromCSRFormat_Symbolic(Mat mat, const PetscInt mat_j[], const PetscInt mat_i[])
625: {
626:   Mat_MPIAIJ *aij    = (Mat_MPIAIJ *)mat->data;
627:   Mat         A      = aij->A; /* diagonal part of the matrix */
628:   Mat         B      = aij->B; /* off-diagonal part of the matrix */
629:   Mat_SeqAIJ *a      = (Mat_SeqAIJ *)A->data;
630:   Mat_SeqAIJ *b      = (Mat_SeqAIJ *)B->data;
631:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, col;
632:   PetscInt   *ailen = a->ilen, *aj = a->j;
633:   PetscInt   *bilen = b->ilen, *bj = b->j;
634:   PetscInt    am          = aij->A->rmap->n, j;
635:   PetscInt    diag_so_far = 0, dnz;
636:   PetscInt    offd_so_far = 0, onz;

638:   PetscFunctionBegin;
639:   /* Iterate over all rows of the matrix */
640:   for (j = 0; j < am; j++) {
641:     dnz = onz = 0;
642:     /*  Iterate over all non-zero columns of the current row */
643:     for (col = mat_i[j]; col < mat_i[j + 1]; col++) {
644:       /* If column is in the diagonal */
645:       if (mat_j[col] >= cstart && mat_j[col] < cend) {
646:         aj[diag_so_far++] = mat_j[col] - cstart;
647:         dnz++;
648:       } else { /* off-diagonal entries */
649:         bj[offd_so_far++] = mat_j[col];
650:         onz++;
651:       }
652:     }
653:     ailen[j] = dnz;
654:     bilen[j] = onz;
655:   }
656:   PetscFunctionReturn(PETSC_SUCCESS);
657: }

659: /*
660:     This function sets the local j, a and ilen arrays (of the diagonal and off-diagonal part) of an MPIAIJ-matrix.
661:     The values in mat_i have to be sorted and the values in mat_j have to be sorted for each row (CSR-like).
662:     No off-processor parts off the matrix are allowed here, they are set at a later point by MatSetValues_MPIAIJ.
663:     Also, mat->was_assembled has to be false, otherwise the statement aj[rowstart_diag+dnz_row] = mat_j[col] - cstart;
664:     would not be true and the more complex MatSetValues_MPIAIJ has to be used.
665: */
666: PetscErrorCode MatSetValues_MPIAIJ_CopyFromCSRFormat(Mat mat, const PetscInt mat_j[], const PetscInt mat_i[], const PetscScalar mat_a[])
667: {
668:   Mat_MPIAIJ  *aij  = (Mat_MPIAIJ *)mat->data;
669:   Mat          A    = aij->A; /* diagonal part of the matrix */
670:   Mat          B    = aij->B; /* off-diagonal part of the matrix */
671:   Mat_SeqAIJ  *aijd = (Mat_SeqAIJ *)(aij->A)->data, *aijo = (Mat_SeqAIJ *)(aij->B)->data;
672:   Mat_SeqAIJ  *a      = (Mat_SeqAIJ *)A->data;
673:   Mat_SeqAIJ  *b      = (Mat_SeqAIJ *)B->data;
674:   PetscInt     cstart = mat->cmap->rstart, cend = mat->cmap->rend;
675:   PetscInt    *ailen = a->ilen, *aj = a->j;
676:   PetscInt    *bilen = b->ilen, *bj = b->j;
677:   PetscInt     am          = aij->A->rmap->n, j;
678:   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. */
679:   PetscInt     col, dnz_row, onz_row, rowstart_diag, rowstart_offd;
680:   PetscScalar *aa = a->a, *ba = b->a;

682:   PetscFunctionBegin;
683:   /* Iterate over all rows of the matrix */
684:   for (j = 0; j < am; j++) {
685:     dnz_row = onz_row = 0;
686:     rowstart_offd     = full_offd_i[j];
687:     rowstart_diag     = full_diag_i[j];
688:     /*  Iterate over all non-zero columns of the current row */
689:     for (col = mat_i[j]; col < mat_i[j + 1]; col++) {
690:       /* If column is in the diagonal */
691:       if (mat_j[col] >= cstart && mat_j[col] < cend) {
692:         aj[rowstart_diag + dnz_row] = mat_j[col] - cstart;
693:         aa[rowstart_diag + dnz_row] = mat_a[col];
694:         dnz_row++;
695:       } else { /* off-diagonal entries */
696:         bj[rowstart_offd + onz_row] = mat_j[col];
697:         ba[rowstart_offd + onz_row] = mat_a[col];
698:         onz_row++;
699:       }
700:     }
701:     ailen[j] = dnz_row;
702:     bilen[j] = onz_row;
703:   }
704:   PetscFunctionReturn(PETSC_SUCCESS);
705: }

707: static PetscErrorCode MatGetValues_MPIAIJ(Mat mat, PetscInt m, const PetscInt idxm[], PetscInt n, const PetscInt idxn[], PetscScalar v[])
708: {
709:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
710:   PetscInt    i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
711:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;

713:   PetscFunctionBegin;
714:   for (i = 0; i < m; i++) {
715:     if (idxm[i] < 0) continue; /* negative row */
716:     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);
717:     if (idxm[i] >= rstart && idxm[i] < rend) {
718:       row = idxm[i] - rstart;
719:       for (j = 0; j < n; j++) {
720:         if (idxn[j] < 0) continue; /* negative column */
721:         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);
722:         if (idxn[j] >= cstart && idxn[j] < cend) {
723:           col = idxn[j] - cstart;
724:           PetscCall(MatGetValues(aij->A, 1, &row, 1, &col, v + i * n + j));
725:         } else {
726:           if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
727: #if defined(PETSC_USE_CTABLE)
728:           PetscCall(PetscHMapIGetWithDefault(aij->colmap, idxn[j] + 1, 0, &col));
729:           col--;
730: #else
731:           col = aij->colmap[idxn[j]] - 1;
732: #endif
733:           if ((col < 0) || (aij->garray[col] != idxn[j])) *(v + i * n + j) = 0.0;
734:           else PetscCall(MatGetValues(aij->B, 1, &row, 1, &col, v + i * n + j));
735:         }
736:       }
737:     } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "Only local values currently supported");
738:   }
739:   PetscFunctionReturn(PETSC_SUCCESS);
740: }

742: static PetscErrorCode MatAssemblyBegin_MPIAIJ(Mat mat, MatAssemblyType mode)
743: {
744:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
745:   PetscInt    nstash, reallocs;

747:   PetscFunctionBegin;
748:   if (aij->donotstash || mat->nooffprocentries) PetscFunctionReturn(PETSC_SUCCESS);

750:   PetscCall(MatStashScatterBegin_Private(mat, &mat->stash, mat->rmap->range));
751:   PetscCall(MatStashGetInfo_Private(&mat->stash, &nstash, &reallocs));
752:   PetscCall(PetscInfo(aij->A, "Stash has %" PetscInt_FMT " entries, uses %" PetscInt_FMT " mallocs.\n", nstash, reallocs));
753:   PetscFunctionReturn(PETSC_SUCCESS);
754: }

756: PetscErrorCode MatAssemblyEnd_MPIAIJ(Mat mat, MatAssemblyType mode)
757: {
758:   Mat_MPIAIJ  *aij = (Mat_MPIAIJ *)mat->data;
759:   PetscMPIInt  n;
760:   PetscInt     i, j, rstart, ncols, flg;
761:   PetscInt    *row, *col;
762:   PetscBool    other_disassembled;
763:   PetscScalar *val;

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

767:   PetscFunctionBegin;
768:   if (!aij->donotstash && !mat->nooffprocentries) {
769:     while (1) {
770:       PetscCall(MatStashScatterGetMesg_Private(&mat->stash, &n, &row, &col, &val, &flg));
771:       if (!flg) break;

773:       for (i = 0; i < n;) {
774:         /* Now identify the consecutive vals belonging to the same row */
775:         for (j = i, rstart = row[j]; j < n; j++) {
776:           if (row[j] != rstart) break;
777:         }
778:         if (j < n) ncols = j - i;
779:         else ncols = n - i;
780:         /* Now assemble all these values with a single function call */
781:         PetscCall(MatSetValues_MPIAIJ(mat, 1, row + i, ncols, col + i, val + i, mat->insertmode));
782:         i = j;
783:       }
784:     }
785:     PetscCall(MatStashScatterEnd_Private(&mat->stash));
786:   }
787: #if defined(PETSC_HAVE_DEVICE)
788:   if (mat->offloadmask == PETSC_OFFLOAD_CPU) aij->A->offloadmask = PETSC_OFFLOAD_CPU;
789:   /* We call MatBindToCPU() on aij->A and aij->B here, because if MatBindToCPU_MPIAIJ() is called before assembly, it cannot bind these. */
790:   if (mat->boundtocpu) {
791:     PetscCall(MatBindToCPU(aij->A, PETSC_TRUE));
792:     PetscCall(MatBindToCPU(aij->B, PETSC_TRUE));
793:   }
794: #endif
795:   PetscCall(MatAssemblyBegin(aij->A, mode));
796:   PetscCall(MatAssemblyEnd(aij->A, mode));

798:   /* determine if any processor has disassembled, if so we must
799:      also disassemble ourself, in order that we may reassemble. */
800:   /*
801:      if nonzero structure of submatrix B cannot change then we know that
802:      no processor disassembled thus we can skip this stuff
803:   */
804:   if (!((Mat_SeqAIJ *)aij->B->data)->nonew) {
805:     PetscCall(MPIU_Allreduce(&mat->was_assembled, &other_disassembled, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));
806:     if (mat->was_assembled && !other_disassembled) { /* mat on this rank has reduced off-diag B with local col ids, but globally it does not */
807:       PetscCall(MatDisAssemble_MPIAIJ(mat));
808:     }
809:   }
810:   if (!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) PetscCall(MatSetUpMultiply_MPIAIJ(mat));
811:   PetscCall(MatSetOption(aij->B, MAT_USE_INODES, PETSC_FALSE));
812: #if defined(PETSC_HAVE_DEVICE)
813:   if (mat->offloadmask == PETSC_OFFLOAD_CPU && aij->B->offloadmask != PETSC_OFFLOAD_UNALLOCATED) aij->B->offloadmask = PETSC_OFFLOAD_CPU;
814: #endif
815:   PetscCall(MatAssemblyBegin(aij->B, mode));
816:   PetscCall(MatAssemblyEnd(aij->B, mode));

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

820:   aij->rowvalues = NULL;

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

824:   /* if no new nonzero locations are allowed in matrix then only set the matrix state the first time through */
825:   if ((!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) || !((Mat_SeqAIJ *)(aij->A->data))->nonew) {
826:     PetscObjectState state = aij->A->nonzerostate + aij->B->nonzerostate;
827:     PetscCall(MPIU_Allreduce(&state, &mat->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)mat)));
828:   }
829: #if defined(PETSC_HAVE_DEVICE)
830:   mat->offloadmask = PETSC_OFFLOAD_BOTH;
831: #endif
832:   PetscFunctionReturn(PETSC_SUCCESS);
833: }

835: static PetscErrorCode MatZeroEntries_MPIAIJ(Mat A)
836: {
837:   Mat_MPIAIJ *l = (Mat_MPIAIJ *)A->data;

839:   PetscFunctionBegin;
840:   PetscCall(MatZeroEntries(l->A));
841:   PetscCall(MatZeroEntries(l->B));
842:   PetscFunctionReturn(PETSC_SUCCESS);
843: }

845: static PetscErrorCode MatZeroRows_MPIAIJ(Mat A, PetscInt N, const PetscInt rows[], PetscScalar diag, Vec x, Vec b)
846: {
847:   Mat_MPIAIJ      *mat = (Mat_MPIAIJ *)A->data;
848:   PetscObjectState sA, sB;
849:   PetscInt        *lrows;
850:   PetscInt         r, len;
851:   PetscBool        cong, lch, gch;

853:   PetscFunctionBegin;
854:   /* get locally owned rows */
855:   PetscCall(MatZeroRowsMapLocal_Private(A, N, rows, &len, &lrows));
856:   PetscCall(MatHasCongruentLayouts(A, &cong));
857:   /* fix right hand side if needed */
858:   if (x && b) {
859:     const PetscScalar *xx;
860:     PetscScalar       *bb;

862:     PetscCheck(cong, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Need matching row/col layout");
863:     PetscCall(VecGetArrayRead(x, &xx));
864:     PetscCall(VecGetArray(b, &bb));
865:     for (r = 0; r < len; ++r) bb[lrows[r]] = diag * xx[lrows[r]];
866:     PetscCall(VecRestoreArrayRead(x, &xx));
867:     PetscCall(VecRestoreArray(b, &bb));
868:   }

870:   sA = mat->A->nonzerostate;
871:   sB = mat->B->nonzerostate;

873:   if (diag != 0.0 && cong) {
874:     PetscCall(MatZeroRows(mat->A, len, lrows, diag, NULL, NULL));
875:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
876:   } else if (diag != 0.0) { /* non-square or non congruent layouts -> if keepnonzeropattern is false, we allow for new insertion */
877:     Mat_SeqAIJ *aijA = (Mat_SeqAIJ *)mat->A->data;
878:     Mat_SeqAIJ *aijB = (Mat_SeqAIJ *)mat->B->data;
879:     PetscInt    nnwA, nnwB;
880:     PetscBool   nnzA, nnzB;

882:     nnwA = aijA->nonew;
883:     nnwB = aijB->nonew;
884:     nnzA = aijA->keepnonzeropattern;
885:     nnzB = aijB->keepnonzeropattern;
886:     if (!nnzA) {
887:       PetscCall(PetscInfo(mat->A, "Requested to not keep the pattern and add a nonzero diagonal; may encounter reallocations on diagonal block.\n"));
888:       aijA->nonew = 0;
889:     }
890:     if (!nnzB) {
891:       PetscCall(PetscInfo(mat->B, "Requested to not keep the pattern and add a nonzero diagonal; may encounter reallocations on off-diagonal block.\n"));
892:       aijB->nonew = 0;
893:     }
894:     /* Must zero here before the next loop */
895:     PetscCall(MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL));
896:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
897:     for (r = 0; r < len; ++r) {
898:       const PetscInt row = lrows[r] + A->rmap->rstart;
899:       if (row >= A->cmap->N) continue;
900:       PetscCall(MatSetValues(A, 1, &row, 1, &row, &diag, INSERT_VALUES));
901:     }
902:     aijA->nonew = nnwA;
903:     aijB->nonew = nnwB;
904:   } else {
905:     PetscCall(MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL));
906:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
907:   }
908:   PetscCall(PetscFree(lrows));
909:   PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
910:   PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));

912:   /* reduce nonzerostate */
913:   lch = (PetscBool)(sA != mat->A->nonzerostate || sB != mat->B->nonzerostate);
914:   PetscCall(MPIU_Allreduce(&lch, &gch, 1, MPIU_BOOL, MPI_LOR, PetscObjectComm((PetscObject)A)));
915:   if (gch) A->nonzerostate++;
916:   PetscFunctionReturn(PETSC_SUCCESS);
917: }

919: static PetscErrorCode MatZeroRowsColumns_MPIAIJ(Mat A, PetscInt N, const PetscInt rows[], PetscScalar diag, Vec x, Vec b)
920: {
921:   Mat_MPIAIJ        *l = (Mat_MPIAIJ *)A->data;
922:   PetscMPIInt        n = A->rmap->n;
923:   PetscInt           i, j, r, m, len = 0;
924:   PetscInt          *lrows, *owners = A->rmap->range;
925:   PetscMPIInt        p = 0;
926:   PetscSFNode       *rrows;
927:   PetscSF            sf;
928:   const PetscScalar *xx;
929:   PetscScalar       *bb, *mask, *aij_a;
930:   Vec                xmask, lmask;
931:   Mat_SeqAIJ        *aij = (Mat_SeqAIJ *)l->B->data;
932:   const PetscInt    *aj, *ii, *ridx;
933:   PetscScalar       *aa;

935:   PetscFunctionBegin;
936:   /* Create SF where leaves are input rows and roots are owned rows */
937:   PetscCall(PetscMalloc1(n, &lrows));
938:   for (r = 0; r < n; ++r) lrows[r] = -1;
939:   PetscCall(PetscMalloc1(N, &rrows));
940:   for (r = 0; r < N; ++r) {
941:     const PetscInt idx = rows[r];
942:     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);
943:     if (idx < owners[p] || owners[p + 1] <= idx) { /* short-circuit the search if the last p owns this row too */
944:       PetscCall(PetscLayoutFindOwner(A->rmap, idx, &p));
945:     }
946:     rrows[r].rank  = p;
947:     rrows[r].index = rows[r] - owners[p];
948:   }
949:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
950:   PetscCall(PetscSFSetGraph(sf, n, N, NULL, PETSC_OWN_POINTER, rrows, PETSC_OWN_POINTER));
951:   /* Collect flags for rows to be zeroed */
952:   PetscCall(PetscSFReduceBegin(sf, MPIU_INT, (PetscInt *)rows, lrows, MPI_LOR));
953:   PetscCall(PetscSFReduceEnd(sf, MPIU_INT, (PetscInt *)rows, lrows, MPI_LOR));
954:   PetscCall(PetscSFDestroy(&sf));
955:   /* Compress and put in row numbers */
956:   for (r = 0; r < n; ++r)
957:     if (lrows[r] >= 0) lrows[len++] = r;
958:   /* zero diagonal part of matrix */
959:   PetscCall(MatZeroRowsColumns(l->A, len, lrows, diag, x, b));
960:   /* handle off-diagonal part of matrix */
961:   PetscCall(MatCreateVecs(A, &xmask, NULL));
962:   PetscCall(VecDuplicate(l->lvec, &lmask));
963:   PetscCall(VecGetArray(xmask, &bb));
964:   for (i = 0; i < len; i++) bb[lrows[i]] = 1;
965:   PetscCall(VecRestoreArray(xmask, &bb));
966:   PetscCall(VecScatterBegin(l->Mvctx, xmask, lmask, ADD_VALUES, SCATTER_FORWARD));
967:   PetscCall(VecScatterEnd(l->Mvctx, xmask, lmask, ADD_VALUES, SCATTER_FORWARD));
968:   PetscCall(VecDestroy(&xmask));
969:   if (x && b) { /* this code is buggy when the row and column layout don't match */
970:     PetscBool cong;

972:     PetscCall(MatHasCongruentLayouts(A, &cong));
973:     PetscCheck(cong, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Need matching row/col layout");
974:     PetscCall(VecScatterBegin(l->Mvctx, x, l->lvec, INSERT_VALUES, SCATTER_FORWARD));
975:     PetscCall(VecScatterEnd(l->Mvctx, x, l->lvec, INSERT_VALUES, SCATTER_FORWARD));
976:     PetscCall(VecGetArrayRead(l->lvec, &xx));
977:     PetscCall(VecGetArray(b, &bb));
978:   }
979:   PetscCall(VecGetArray(lmask, &mask));
980:   /* remove zeroed rows of off-diagonal matrix */
981:   PetscCall(MatSeqAIJGetArray(l->B, &aij_a));
982:   ii = aij->i;
983:   for (i = 0; i < len; i++) PetscCall(PetscArrayzero(aij_a + ii[lrows[i]], ii[lrows[i] + 1] - ii[lrows[i]]));
984:   /* loop over all elements of off process part of matrix zeroing removed columns*/
985:   if (aij->compressedrow.use) {
986:     m    = aij->compressedrow.nrows;
987:     ii   = aij->compressedrow.i;
988:     ridx = aij->compressedrow.rindex;
989:     for (i = 0; i < m; i++) {
990:       n  = ii[i + 1] - ii[i];
991:       aj = aij->j + ii[i];
992:       aa = aij_a + ii[i];

994:       for (j = 0; j < n; j++) {
995:         if (PetscAbsScalar(mask[*aj])) {
996:           if (b) bb[*ridx] -= *aa * xx[*aj];
997:           *aa = 0.0;
998:         }
999:         aa++;
1000:         aj++;
1001:       }
1002:       ridx++;
1003:     }
1004:   } else { /* do not use compressed row format */
1005:     m = l->B->rmap->n;
1006:     for (i = 0; i < m; i++) {
1007:       n  = ii[i + 1] - ii[i];
1008:       aj = aij->j + ii[i];
1009:       aa = aij_a + ii[i];
1010:       for (j = 0; j < n; j++) {
1011:         if (PetscAbsScalar(mask[*aj])) {
1012:           if (b) bb[i] -= *aa * xx[*aj];
1013:           *aa = 0.0;
1014:         }
1015:         aa++;
1016:         aj++;
1017:       }
1018:     }
1019:   }
1020:   if (x && b) {
1021:     PetscCall(VecRestoreArray(b, &bb));
1022:     PetscCall(VecRestoreArrayRead(l->lvec, &xx));
1023:   }
1024:   PetscCall(MatSeqAIJRestoreArray(l->B, &aij_a));
1025:   PetscCall(VecRestoreArray(lmask, &mask));
1026:   PetscCall(VecDestroy(&lmask));
1027:   PetscCall(PetscFree(lrows));

1029:   /* only change matrix nonzero state if pattern was allowed to be changed */
1030:   if (!((Mat_SeqAIJ *)(l->A->data))->keepnonzeropattern) {
1031:     PetscObjectState state = l->A->nonzerostate + l->B->nonzerostate;
1032:     PetscCall(MPIU_Allreduce(&state, &A->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)A)));
1033:   }
1034:   PetscFunctionReturn(PETSC_SUCCESS);
1035: }

1037: static PetscErrorCode MatMult_MPIAIJ(Mat A, Vec xx, Vec yy)
1038: {
1039:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
1040:   PetscInt    nt;
1041:   VecScatter  Mvctx = a->Mvctx;

1043:   PetscFunctionBegin;
1044:   PetscCall(VecGetLocalSize(xx, &nt));
1045:   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);
1046:   PetscCall(VecScatterBegin(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1047:   PetscUseTypeMethod(a->A, mult, xx, yy);
1048:   PetscCall(VecScatterEnd(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1049:   PetscUseTypeMethod(a->B, multadd, a->lvec, yy, yy);
1050:   PetscFunctionReturn(PETSC_SUCCESS);
1051: }

1053: static PetscErrorCode MatMultDiagonalBlock_MPIAIJ(Mat A, Vec bb, Vec xx)
1054: {
1055:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1057:   PetscFunctionBegin;
1058:   PetscCall(MatMultDiagonalBlock(a->A, bb, xx));
1059:   PetscFunctionReturn(PETSC_SUCCESS);
1060: }

1062: static PetscErrorCode MatMultAdd_MPIAIJ(Mat A, Vec xx, Vec yy, Vec zz)
1063: {
1064:   Mat_MPIAIJ *a     = (Mat_MPIAIJ *)A->data;
1065:   VecScatter  Mvctx = a->Mvctx;

1067:   PetscFunctionBegin;
1068:   PetscCall(VecScatterBegin(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1069:   PetscCall((*a->A->ops->multadd)(a->A, xx, yy, zz));
1070:   PetscCall(VecScatterEnd(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1071:   PetscCall((*a->B->ops->multadd)(a->B, a->lvec, zz, zz));
1072:   PetscFunctionReturn(PETSC_SUCCESS);
1073: }

1075: static PetscErrorCode MatMultTranspose_MPIAIJ(Mat A, Vec xx, Vec yy)
1076: {
1077:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1079:   PetscFunctionBegin;
1080:   /* do nondiagonal part */
1081:   PetscCall((*a->B->ops->multtranspose)(a->B, xx, a->lvec));
1082:   /* do local part */
1083:   PetscCall((*a->A->ops->multtranspose)(a->A, xx, yy));
1084:   /* add partial results together */
1085:   PetscCall(VecScatterBegin(a->Mvctx, a->lvec, yy, ADD_VALUES, SCATTER_REVERSE));
1086:   PetscCall(VecScatterEnd(a->Mvctx, a->lvec, yy, ADD_VALUES, SCATTER_REVERSE));
1087:   PetscFunctionReturn(PETSC_SUCCESS);
1088: }

1090: static PetscErrorCode MatIsTranspose_MPIAIJ(Mat Amat, Mat Bmat, PetscReal tol, PetscBool *f)
1091: {
1092:   MPI_Comm    comm;
1093:   Mat_MPIAIJ *Aij = (Mat_MPIAIJ *)Amat->data, *Bij = (Mat_MPIAIJ *)Bmat->data;
1094:   Mat         Adia = Aij->A, Bdia = Bij->A, Aoff, Boff, *Aoffs, *Boffs;
1095:   IS          Me, Notme;
1096:   PetscInt    M, N, first, last, *notme, i;
1097:   PetscBool   lf;
1098:   PetscMPIInt size;

1100:   PetscFunctionBegin;
1101:   /* Easy test: symmetric diagonal block */
1102:   PetscCall(MatIsTranspose(Adia, Bdia, tol, &lf));
1103:   PetscCall(MPIU_Allreduce(&lf, f, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)Amat)));
1104:   if (!*f) PetscFunctionReturn(PETSC_SUCCESS);
1105:   PetscCall(PetscObjectGetComm((PetscObject)Amat, &comm));
1106:   PetscCallMPI(MPI_Comm_size(comm, &size));
1107:   if (size == 1) PetscFunctionReturn(PETSC_SUCCESS);

1109:   /* Hard test: off-diagonal block. This takes a MatCreateSubMatrix. */
1110:   PetscCall(MatGetSize(Amat, &M, &N));
1111:   PetscCall(MatGetOwnershipRange(Amat, &first, &last));
1112:   PetscCall(PetscMalloc1(N - last + first, &notme));
1113:   for (i = 0; i < first; i++) notme[i] = i;
1114:   for (i = last; i < M; i++) notme[i - last + first] = i;
1115:   PetscCall(ISCreateGeneral(MPI_COMM_SELF, N - last + first, notme, PETSC_COPY_VALUES, &Notme));
1116:   PetscCall(ISCreateStride(MPI_COMM_SELF, last - first, first, 1, &Me));
1117:   PetscCall(MatCreateSubMatrices(Amat, 1, &Me, &Notme, MAT_INITIAL_MATRIX, &Aoffs));
1118:   Aoff = Aoffs[0];
1119:   PetscCall(MatCreateSubMatrices(Bmat, 1, &Notme, &Me, MAT_INITIAL_MATRIX, &Boffs));
1120:   Boff = Boffs[0];
1121:   PetscCall(MatIsTranspose(Aoff, Boff, tol, f));
1122:   PetscCall(MatDestroyMatrices(1, &Aoffs));
1123:   PetscCall(MatDestroyMatrices(1, &Boffs));
1124:   PetscCall(ISDestroy(&Me));
1125:   PetscCall(ISDestroy(&Notme));
1126:   PetscCall(PetscFree(notme));
1127:   PetscFunctionReturn(PETSC_SUCCESS);
1128: }

1130: static PetscErrorCode MatIsSymmetric_MPIAIJ(Mat A, PetscReal tol, PetscBool *f)
1131: {
1132:   PetscFunctionBegin;
1133:   PetscCall(MatIsTranspose_MPIAIJ(A, A, tol, f));
1134:   PetscFunctionReturn(PETSC_SUCCESS);
1135: }

1137: static PetscErrorCode MatMultTransposeAdd_MPIAIJ(Mat A, Vec xx, Vec yy, Vec zz)
1138: {
1139:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1141:   PetscFunctionBegin;
1142:   /* do nondiagonal part */
1143:   PetscCall((*a->B->ops->multtranspose)(a->B, xx, a->lvec));
1144:   /* do local part */
1145:   PetscCall((*a->A->ops->multtransposeadd)(a->A, xx, yy, zz));
1146:   /* add partial results together */
1147:   PetscCall(VecScatterBegin(a->Mvctx, a->lvec, zz, ADD_VALUES, SCATTER_REVERSE));
1148:   PetscCall(VecScatterEnd(a->Mvctx, a->lvec, zz, ADD_VALUES, SCATTER_REVERSE));
1149:   PetscFunctionReturn(PETSC_SUCCESS);
1150: }

1152: /*
1153:   This only works correctly for square matrices where the subblock A->A is the
1154:    diagonal block
1155: */
1156: static PetscErrorCode MatGetDiagonal_MPIAIJ(Mat A, Vec v)
1157: {
1158:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1160:   PetscFunctionBegin;
1161:   PetscCheck(A->rmap->N == A->cmap->N, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Supports only square matrix where A->A is diag block");
1162:   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");
1163:   PetscCall(MatGetDiagonal(a->A, v));
1164:   PetscFunctionReturn(PETSC_SUCCESS);
1165: }

1167: static PetscErrorCode MatScale_MPIAIJ(Mat A, PetscScalar aa)
1168: {
1169:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1171:   PetscFunctionBegin;
1172:   PetscCall(MatScale(a->A, aa));
1173:   PetscCall(MatScale(a->B, aa));
1174:   PetscFunctionReturn(PETSC_SUCCESS);
1175: }

1177: static PetscErrorCode MatView_MPIAIJ_Binary(Mat mat, PetscViewer viewer)
1178: {
1179:   Mat_MPIAIJ        *aij    = (Mat_MPIAIJ *)mat->data;
1180:   Mat_SeqAIJ        *A      = (Mat_SeqAIJ *)aij->A->data;
1181:   Mat_SeqAIJ        *B      = (Mat_SeqAIJ *)aij->B->data;
1182:   const PetscInt    *garray = aij->garray;
1183:   const PetscScalar *aa, *ba;
1184:   PetscInt           header[4], M, N, m, rs, cs, cnt, i, ja, jb;
1185:   PetscInt64         nz, hnz;
1186:   PetscInt          *rowlens;
1187:   PetscInt          *colidxs;
1188:   PetscScalar       *matvals;
1189:   PetscMPIInt        rank;

1191:   PetscFunctionBegin;
1192:   PetscCall(PetscViewerSetUp(viewer));

1194:   M  = mat->rmap->N;
1195:   N  = mat->cmap->N;
1196:   m  = mat->rmap->n;
1197:   rs = mat->rmap->rstart;
1198:   cs = mat->cmap->rstart;
1199:   nz = A->nz + B->nz;

1201:   /* write matrix header */
1202:   header[0] = MAT_FILE_CLASSID;
1203:   header[1] = M;
1204:   header[2] = N;
1205:   PetscCallMPI(MPI_Reduce(&nz, &hnz, 1, MPIU_INT64, MPI_SUM, 0, PetscObjectComm((PetscObject)mat)));
1206:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)mat), &rank));
1207:   if (rank == 0) {
1208:     if (hnz > PETSC_MAX_INT) header[3] = PETSC_MAX_INT;
1209:     else header[3] = (PetscInt)hnz;
1210:   }
1211:   PetscCall(PetscViewerBinaryWrite(viewer, header, 4, PETSC_INT));

1213:   /* fill in and store row lengths  */
1214:   PetscCall(PetscMalloc1(m, &rowlens));
1215:   for (i = 0; i < m; i++) rowlens[i] = A->i[i + 1] - A->i[i] + B->i[i + 1] - B->i[i];
1216:   PetscCall(PetscViewerBinaryWriteAll(viewer, rowlens, m, rs, M, PETSC_INT));
1217:   PetscCall(PetscFree(rowlens));

1219:   /* fill in and store column indices */
1220:   PetscCall(PetscMalloc1(nz, &colidxs));
1221:   for (cnt = 0, i = 0; i < m; i++) {
1222:     for (jb = B->i[i]; jb < B->i[i + 1]; jb++) {
1223:       if (garray[B->j[jb]] > cs) break;
1224:       colidxs[cnt++] = garray[B->j[jb]];
1225:     }
1226:     for (ja = A->i[i]; ja < A->i[i + 1]; ja++) colidxs[cnt++] = A->j[ja] + cs;
1227:     for (; jb < B->i[i + 1]; jb++) colidxs[cnt++] = garray[B->j[jb]];
1228:   }
1229:   PetscCheck(cnt == nz, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Internal PETSc error: cnt = %" PetscInt_FMT " nz = %" PetscInt64_FMT, cnt, nz);
1230:   PetscCall(PetscViewerBinaryWriteAll(viewer, colidxs, nz, PETSC_DETERMINE, PETSC_DETERMINE, PETSC_INT));
1231:   PetscCall(PetscFree(colidxs));

1233:   /* fill in and store nonzero values */
1234:   PetscCall(MatSeqAIJGetArrayRead(aij->A, &aa));
1235:   PetscCall(MatSeqAIJGetArrayRead(aij->B, &ba));
1236:   PetscCall(PetscMalloc1(nz, &matvals));
1237:   for (cnt = 0, i = 0; i < m; i++) {
1238:     for (jb = B->i[i]; jb < B->i[i + 1]; jb++) {
1239:       if (garray[B->j[jb]] > cs) break;
1240:       matvals[cnt++] = ba[jb];
1241:     }
1242:     for (ja = A->i[i]; ja < A->i[i + 1]; ja++) matvals[cnt++] = aa[ja];
1243:     for (; jb < B->i[i + 1]; jb++) matvals[cnt++] = ba[jb];
1244:   }
1245:   PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &aa));
1246:   PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &ba));
1247:   PetscCheck(cnt == nz, PETSC_COMM_SELF, PETSC_ERR_LIB, "Internal PETSc error: cnt = %" PetscInt_FMT " nz = %" PetscInt64_FMT, cnt, nz);
1248:   PetscCall(PetscViewerBinaryWriteAll(viewer, matvals, nz, PETSC_DETERMINE, PETSC_DETERMINE, PETSC_SCALAR));
1249:   PetscCall(PetscFree(matvals));

1251:   /* write block size option to the viewer's .info file */
1252:   PetscCall(MatView_Binary_BlockSizes(mat, viewer));
1253:   PetscFunctionReturn(PETSC_SUCCESS);
1254: }

1256: #include <petscdraw.h>
1257: static PetscErrorCode MatView_MPIAIJ_ASCIIorDraworSocket(Mat mat, PetscViewer viewer)
1258: {
1259:   Mat_MPIAIJ       *aij  = (Mat_MPIAIJ *)mat->data;
1260:   PetscMPIInt       rank = aij->rank, size = aij->size;
1261:   PetscBool         isdraw, iascii, isbinary;
1262:   PetscViewer       sviewer;
1263:   PetscViewerFormat format;

1265:   PetscFunctionBegin;
1266:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERDRAW, &isdraw));
1267:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
1268:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
1269:   if (iascii) {
1270:     PetscCall(PetscViewerGetFormat(viewer, &format));
1271:     if (format == PETSC_VIEWER_LOAD_BALANCE) {
1272:       PetscInt i, nmax = 0, nmin = PETSC_MAX_INT, navg = 0, *nz, nzlocal = ((Mat_SeqAIJ *)(aij->A->data))->nz + ((Mat_SeqAIJ *)(aij->B->data))->nz;
1273:       PetscCall(PetscMalloc1(size, &nz));
1274:       PetscCallMPI(MPI_Allgather(&nzlocal, 1, MPIU_INT, nz, 1, MPIU_INT, PetscObjectComm((PetscObject)mat)));
1275:       for (i = 0; i < (PetscInt)size; i++) {
1276:         nmax = PetscMax(nmax, nz[i]);
1277:         nmin = PetscMin(nmin, nz[i]);
1278:         navg += nz[i];
1279:       }
1280:       PetscCall(PetscFree(nz));
1281:       navg = navg / size;
1282:       PetscCall(PetscViewerASCIIPrintf(viewer, "Load Balance - Nonzeros: Min %" PetscInt_FMT "  avg %" PetscInt_FMT "  max %" PetscInt_FMT "\n", nmin, navg, nmax));
1283:       PetscFunctionReturn(PETSC_SUCCESS);
1284:     }
1285:     PetscCall(PetscViewerGetFormat(viewer, &format));
1286:     if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
1287:       MatInfo   info;
1288:       PetscInt *inodes = NULL;

1290:       PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)mat), &rank));
1291:       PetscCall(MatGetInfo(mat, MAT_LOCAL, &info));
1292:       PetscCall(MatInodeGetInodeSizes(aij->A, NULL, &inodes, NULL));
1293:       PetscCall(PetscViewerASCIIPushSynchronized(viewer));
1294:       if (!inodes) {
1295:         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,
1296:                                                      (double)info.memory));
1297:       } else {
1298:         PetscCall(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,
1299:                                                      (double)info.memory));
1300:       }
1301:       PetscCall(MatGetInfo(aij->A, MAT_LOCAL, &info));
1302:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] on-diagonal part: nz %" PetscInt_FMT " \n", rank, (PetscInt)info.nz_used));
1303:       PetscCall(MatGetInfo(aij->B, MAT_LOCAL, &info));
1304:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] off-diagonal part: nz %" PetscInt_FMT " \n", rank, (PetscInt)info.nz_used));
1305:       PetscCall(PetscViewerFlush(viewer));
1306:       PetscCall(PetscViewerASCIIPopSynchronized(viewer));
1307:       PetscCall(PetscViewerASCIIPrintf(viewer, "Information on VecScatter used in matrix-vector product: \n"));
1308:       PetscCall(VecScatterView(aij->Mvctx, viewer));
1309:       PetscFunctionReturn(PETSC_SUCCESS);
1310:     } else if (format == PETSC_VIEWER_ASCII_INFO) {
1311:       PetscInt inodecount, inodelimit, *inodes;
1312:       PetscCall(MatInodeGetInodeSizes(aij->A, &inodecount, &inodes, &inodelimit));
1313:       if (inodes) {
1314:         PetscCall(PetscViewerASCIIPrintf(viewer, "using I-node (on process 0) routines: found %" PetscInt_FMT " nodes, limit used is %" PetscInt_FMT "\n", inodecount, inodelimit));
1315:       } else {
1316:         PetscCall(PetscViewerASCIIPrintf(viewer, "not using I-node (on process 0) routines\n"));
1317:       }
1318:       PetscFunctionReturn(PETSC_SUCCESS);
1319:     } else if (format == PETSC_VIEWER_ASCII_FACTOR_INFO) {
1320:       PetscFunctionReturn(PETSC_SUCCESS);
1321:     }
1322:   } else if (isbinary) {
1323:     if (size == 1) {
1324:       PetscCall(PetscObjectSetName((PetscObject)aij->A, ((PetscObject)mat)->name));
1325:       PetscCall(MatView(aij->A, viewer));
1326:     } else {
1327:       PetscCall(MatView_MPIAIJ_Binary(mat, viewer));
1328:     }
1329:     PetscFunctionReturn(PETSC_SUCCESS);
1330:   } else if (iascii && size == 1) {
1331:     PetscCall(PetscObjectSetName((PetscObject)aij->A, ((PetscObject)mat)->name));
1332:     PetscCall(MatView(aij->A, viewer));
1333:     PetscFunctionReturn(PETSC_SUCCESS);
1334:   } else if (isdraw) {
1335:     PetscDraw draw;
1336:     PetscBool isnull;
1337:     PetscCall(PetscViewerDrawGetDraw(viewer, 0, &draw));
1338:     PetscCall(PetscDrawIsNull(draw, &isnull));
1339:     if (isnull) PetscFunctionReturn(PETSC_SUCCESS);
1340:   }

1342:   { /* assemble the entire matrix onto first processor */
1343:     Mat A = NULL, Av;
1344:     IS  isrow, iscol;

1346:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat), rank == 0 ? mat->rmap->N : 0, 0, 1, &isrow));
1347:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat), rank == 0 ? mat->cmap->N : 0, 0, 1, &iscol));
1348:     PetscCall(MatCreateSubMatrix(mat, isrow, iscol, MAT_INITIAL_MATRIX, &A));
1349:     PetscCall(MatMPIAIJGetSeqAIJ(A, &Av, NULL, NULL));
1350:     /*  The commented code uses MatCreateSubMatrices instead */
1351:     /*
1352:     Mat *AA, A = NULL, Av;
1353:     IS  isrow,iscol;

1355:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat),rank == 0 ? mat->rmap->N : 0,0,1,&isrow));
1356:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat),rank == 0 ? mat->cmap->N : 0,0,1,&iscol));
1357:     PetscCall(MatCreateSubMatrices(mat,1,&isrow,&iscol,MAT_INITIAL_MATRIX,&AA));
1358:     if (rank == 0) {
1359:        PetscCall(PetscObjectReference((PetscObject)AA[0]));
1360:        A    = AA[0];
1361:        Av   = AA[0];
1362:     }
1363:     PetscCall(MatDestroySubMatrices(1,&AA));
1364: */
1365:     PetscCall(ISDestroy(&iscol));
1366:     PetscCall(ISDestroy(&isrow));
1367:     /*
1368:        Everyone has to call to draw the matrix since the graphics waits are
1369:        synchronized across all processors that share the PetscDraw object
1370:     */
1371:     PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
1372:     if (rank == 0) {
1373:       if (((PetscObject)mat)->name) PetscCall(PetscObjectSetName((PetscObject)Av, ((PetscObject)mat)->name));
1374:       PetscCall(MatView_SeqAIJ(Av, sviewer));
1375:     }
1376:     PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
1377:     PetscCall(PetscViewerFlush(viewer));
1378:     PetscCall(MatDestroy(&A));
1379:   }
1380:   PetscFunctionReturn(PETSC_SUCCESS);
1381: }

1383: PetscErrorCode MatView_MPIAIJ(Mat mat, PetscViewer viewer)
1384: {
1385:   PetscBool iascii, isdraw, issocket, isbinary;

1387:   PetscFunctionBegin;
1388:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
1389:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERDRAW, &isdraw));
1390:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
1391:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERSOCKET, &issocket));
1392:   if (iascii || isdraw || isbinary || issocket) PetscCall(MatView_MPIAIJ_ASCIIorDraworSocket(mat, viewer));
1393:   PetscFunctionReturn(PETSC_SUCCESS);
1394: }

1396: static PetscErrorCode MatSOR_MPIAIJ(Mat matin, Vec bb, PetscReal omega, MatSORType flag, PetscReal fshift, PetscInt its, PetscInt lits, Vec xx)
1397: {
1398:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)matin->data;
1399:   Vec         bb1 = NULL;
1400:   PetscBool   hasop;

1402:   PetscFunctionBegin;
1403:   if (flag == SOR_APPLY_UPPER) {
1404:     PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, flag, fshift, lits, 1, xx));
1405:     PetscFunctionReturn(PETSC_SUCCESS);
1406:   }

1408:   if (its > 1 || ~flag & SOR_ZERO_INITIAL_GUESS || flag & SOR_EISENSTAT) PetscCall(VecDuplicate(bb, &bb1));

1410:   if ((flag & SOR_LOCAL_SYMMETRIC_SWEEP) == SOR_LOCAL_SYMMETRIC_SWEEP) {
1411:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1412:       PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, flag, fshift, lits, 1, xx));
1413:       its--;
1414:     }

1416:     while (its--) {
1417:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1418:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1420:       /* update rhs: bb1 = bb - B*x */
1421:       PetscCall(VecScale(mat->lvec, -1.0));
1422:       PetscCall((*mat->B->ops->multadd)(mat->B, mat->lvec, bb, bb1));

1424:       /* local sweep */
1425:       PetscCall((*mat->A->ops->sor)(mat->A, bb1, omega, SOR_SYMMETRIC_SWEEP, fshift, lits, 1, xx));
1426:     }
1427:   } else if (flag & SOR_LOCAL_FORWARD_SWEEP) {
1428:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1429:       PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, flag, fshift, lits, 1, xx));
1430:       its--;
1431:     }
1432:     while (its--) {
1433:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1434:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1436:       /* update rhs: bb1 = bb - B*x */
1437:       PetscCall(VecScale(mat->lvec, -1.0));
1438:       PetscCall((*mat->B->ops->multadd)(mat->B, mat->lvec, bb, bb1));

1440:       /* local sweep */
1441:       PetscCall((*mat->A->ops->sor)(mat->A, bb1, omega, SOR_FORWARD_SWEEP, fshift, lits, 1, xx));
1442:     }
1443:   } else if (flag & SOR_LOCAL_BACKWARD_SWEEP) {
1444:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1445:       PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, flag, fshift, lits, 1, xx));
1446:       its--;
1447:     }
1448:     while (its--) {
1449:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1450:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1452:       /* update rhs: bb1 = bb - B*x */
1453:       PetscCall(VecScale(mat->lvec, -1.0));
1454:       PetscCall((*mat->B->ops->multadd)(mat->B, mat->lvec, bb, bb1));

1456:       /* local sweep */
1457:       PetscCall((*mat->A->ops->sor)(mat->A, bb1, omega, SOR_BACKWARD_SWEEP, fshift, lits, 1, xx));
1458:     }
1459:   } else if (flag & SOR_EISENSTAT) {
1460:     Vec xx1;

1462:     PetscCall(VecDuplicate(bb, &xx1));
1463:     PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, (MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_BACKWARD_SWEEP), fshift, lits, 1, xx));

1465:     PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1466:     PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1467:     if (!mat->diag) {
1468:       PetscCall(MatCreateVecs(matin, &mat->diag, NULL));
1469:       PetscCall(MatGetDiagonal(matin, mat->diag));
1470:     }
1471:     PetscCall(MatHasOperation(matin, MATOP_MULT_DIAGONAL_BLOCK, &hasop));
1472:     if (hasop) {
1473:       PetscCall(MatMultDiagonalBlock(matin, xx, bb1));
1474:     } else {
1475:       PetscCall(VecPointwiseMult(bb1, mat->diag, xx));
1476:     }
1477:     PetscCall(VecAYPX(bb1, (omega - 2.0) / omega, bb));

1479:     PetscCall(MatMultAdd(mat->B, mat->lvec, bb1, bb1));

1481:     /* local sweep */
1482:     PetscCall((*mat->A->ops->sor)(mat->A, bb1, omega, (MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_FORWARD_SWEEP), fshift, lits, 1, xx1));
1483:     PetscCall(VecAXPY(xx, 1.0, xx1));
1484:     PetscCall(VecDestroy(&xx1));
1485:   } else SETERRQ(PetscObjectComm((PetscObject)matin), PETSC_ERR_SUP, "Parallel SOR not supported");

1487:   PetscCall(VecDestroy(&bb1));

1489:   matin->factorerrortype = mat->A->factorerrortype;
1490:   PetscFunctionReturn(PETSC_SUCCESS);
1491: }

1493: static PetscErrorCode MatPermute_MPIAIJ(Mat A, IS rowp, IS colp, Mat *B)
1494: {
1495:   Mat             aA, aB, Aperm;
1496:   const PetscInt *rwant, *cwant, *gcols, *ai, *bi, *aj, *bj;
1497:   PetscScalar    *aa, *ba;
1498:   PetscInt        i, j, m, n, ng, anz, bnz, *dnnz, *onnz, *tdnnz, *tonnz, *rdest, *cdest, *work, *gcdest;
1499:   PetscSF         rowsf, sf;
1500:   IS              parcolp = NULL;
1501:   PetscBool       done;

1503:   PetscFunctionBegin;
1504:   PetscCall(MatGetLocalSize(A, &m, &n));
1505:   PetscCall(ISGetIndices(rowp, &rwant));
1506:   PetscCall(ISGetIndices(colp, &cwant));
1507:   PetscCall(PetscMalloc3(PetscMax(m, n), &work, m, &rdest, n, &cdest));

1509:   /* Invert row permutation to find out where my rows should go */
1510:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &rowsf));
1511:   PetscCall(PetscSFSetGraphLayout(rowsf, A->rmap, A->rmap->n, NULL, PETSC_OWN_POINTER, rwant));
1512:   PetscCall(PetscSFSetFromOptions(rowsf));
1513:   for (i = 0; i < m; i++) work[i] = A->rmap->rstart + i;
1514:   PetscCall(PetscSFReduceBegin(rowsf, MPIU_INT, work, rdest, MPI_REPLACE));
1515:   PetscCall(PetscSFReduceEnd(rowsf, MPIU_INT, work, rdest, MPI_REPLACE));

1517:   /* Invert column permutation to find out where my columns should go */
1518:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1519:   PetscCall(PetscSFSetGraphLayout(sf, A->cmap, A->cmap->n, NULL, PETSC_OWN_POINTER, cwant));
1520:   PetscCall(PetscSFSetFromOptions(sf));
1521:   for (i = 0; i < n; i++) work[i] = A->cmap->rstart + i;
1522:   PetscCall(PetscSFReduceBegin(sf, MPIU_INT, work, cdest, MPI_REPLACE));
1523:   PetscCall(PetscSFReduceEnd(sf, MPIU_INT, work, cdest, MPI_REPLACE));
1524:   PetscCall(PetscSFDestroy(&sf));

1526:   PetscCall(ISRestoreIndices(rowp, &rwant));
1527:   PetscCall(ISRestoreIndices(colp, &cwant));
1528:   PetscCall(MatMPIAIJGetSeqAIJ(A, &aA, &aB, &gcols));

1530:   /* Find out where my gcols should go */
1531:   PetscCall(MatGetSize(aB, NULL, &ng));
1532:   PetscCall(PetscMalloc1(ng, &gcdest));
1533:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1534:   PetscCall(PetscSFSetGraphLayout(sf, A->cmap, ng, NULL, PETSC_OWN_POINTER, gcols));
1535:   PetscCall(PetscSFSetFromOptions(sf));
1536:   PetscCall(PetscSFBcastBegin(sf, MPIU_INT, cdest, gcdest, MPI_REPLACE));
1537:   PetscCall(PetscSFBcastEnd(sf, MPIU_INT, cdest, gcdest, MPI_REPLACE));
1538:   PetscCall(PetscSFDestroy(&sf));

1540:   PetscCall(PetscCalloc4(m, &dnnz, m, &onnz, m, &tdnnz, m, &tonnz));
1541:   PetscCall(MatGetRowIJ(aA, 0, PETSC_FALSE, PETSC_FALSE, &anz, &ai, &aj, &done));
1542:   PetscCall(MatGetRowIJ(aB, 0, PETSC_FALSE, PETSC_FALSE, &bnz, &bi, &bj, &done));
1543:   for (i = 0; i < m; i++) {
1544:     PetscInt    row = rdest[i];
1545:     PetscMPIInt rowner;
1546:     PetscCall(PetscLayoutFindOwner(A->rmap, row, &rowner));
1547:     for (j = ai[i]; j < ai[i + 1]; j++) {
1548:       PetscInt    col = cdest[aj[j]];
1549:       PetscMPIInt cowner;
1550:       PetscCall(PetscLayoutFindOwner(A->cmap, col, &cowner)); /* Could build an index for the columns to eliminate this search */
1551:       if (rowner == cowner) dnnz[i]++;
1552:       else onnz[i]++;
1553:     }
1554:     for (j = bi[i]; j < bi[i + 1]; j++) {
1555:       PetscInt    col = gcdest[bj[j]];
1556:       PetscMPIInt cowner;
1557:       PetscCall(PetscLayoutFindOwner(A->cmap, col, &cowner));
1558:       if (rowner == cowner) dnnz[i]++;
1559:       else onnz[i]++;
1560:     }
1561:   }
1562:   PetscCall(PetscSFBcastBegin(rowsf, MPIU_INT, dnnz, tdnnz, MPI_REPLACE));
1563:   PetscCall(PetscSFBcastEnd(rowsf, MPIU_INT, dnnz, tdnnz, MPI_REPLACE));
1564:   PetscCall(PetscSFBcastBegin(rowsf, MPIU_INT, onnz, tonnz, MPI_REPLACE));
1565:   PetscCall(PetscSFBcastEnd(rowsf, MPIU_INT, onnz, tonnz, MPI_REPLACE));
1566:   PetscCall(PetscSFDestroy(&rowsf));

1568:   PetscCall(MatCreateAIJ(PetscObjectComm((PetscObject)A), A->rmap->n, A->cmap->n, A->rmap->N, A->cmap->N, 0, tdnnz, 0, tonnz, &Aperm));
1569:   PetscCall(MatSeqAIJGetArray(aA, &aa));
1570:   PetscCall(MatSeqAIJGetArray(aB, &ba));
1571:   for (i = 0; i < m; i++) {
1572:     PetscInt *acols = dnnz, *bcols = onnz; /* Repurpose now-unneeded arrays */
1573:     PetscInt  j0, rowlen;
1574:     rowlen = ai[i + 1] - ai[i];
1575:     for (j0 = j = 0; j < rowlen; j0 = j) { /* rowlen could be larger than number of rows m, so sum in batches */
1576:       for (; j < PetscMin(rowlen, j0 + m); j++) acols[j - j0] = cdest[aj[ai[i] + j]];
1577:       PetscCall(MatSetValues(Aperm, 1, &rdest[i], j - j0, acols, aa + ai[i] + j0, INSERT_VALUES));
1578:     }
1579:     rowlen = bi[i + 1] - bi[i];
1580:     for (j0 = j = 0; j < rowlen; j0 = j) {
1581:       for (; j < PetscMin(rowlen, j0 + m); j++) bcols[j - j0] = gcdest[bj[bi[i] + j]];
1582:       PetscCall(MatSetValues(Aperm, 1, &rdest[i], j - j0, bcols, ba + bi[i] + j0, INSERT_VALUES));
1583:     }
1584:   }
1585:   PetscCall(MatAssemblyBegin(Aperm, MAT_FINAL_ASSEMBLY));
1586:   PetscCall(MatAssemblyEnd(Aperm, MAT_FINAL_ASSEMBLY));
1587:   PetscCall(MatRestoreRowIJ(aA, 0, PETSC_FALSE, PETSC_FALSE, &anz, &ai, &aj, &done));
1588:   PetscCall(MatRestoreRowIJ(aB, 0, PETSC_FALSE, PETSC_FALSE, &bnz, &bi, &bj, &done));
1589:   PetscCall(MatSeqAIJRestoreArray(aA, &aa));
1590:   PetscCall(MatSeqAIJRestoreArray(aB, &ba));
1591:   PetscCall(PetscFree4(dnnz, onnz, tdnnz, tonnz));
1592:   PetscCall(PetscFree3(work, rdest, cdest));
1593:   PetscCall(PetscFree(gcdest));
1594:   if (parcolp) PetscCall(ISDestroy(&colp));
1595:   *B = Aperm;
1596:   PetscFunctionReturn(PETSC_SUCCESS);
1597: }

1599: static PetscErrorCode MatGetGhosts_MPIAIJ(Mat mat, PetscInt *nghosts, const PetscInt *ghosts[])
1600: {
1601:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

1603:   PetscFunctionBegin;
1604:   PetscCall(MatGetSize(aij->B, NULL, nghosts));
1605:   if (ghosts) *ghosts = aij->garray;
1606:   PetscFunctionReturn(PETSC_SUCCESS);
1607: }

1609: static PetscErrorCode MatGetInfo_MPIAIJ(Mat matin, MatInfoType flag, MatInfo *info)
1610: {
1611:   Mat_MPIAIJ    *mat = (Mat_MPIAIJ *)matin->data;
1612:   Mat            A = mat->A, B = mat->B;
1613:   PetscLogDouble isend[5], irecv[5];

1615:   PetscFunctionBegin;
1616:   info->block_size = 1.0;
1617:   PetscCall(MatGetInfo(A, MAT_LOCAL, info));

1619:   isend[0] = info->nz_used;
1620:   isend[1] = info->nz_allocated;
1621:   isend[2] = info->nz_unneeded;
1622:   isend[3] = info->memory;
1623:   isend[4] = info->mallocs;

1625:   PetscCall(MatGetInfo(B, MAT_LOCAL, info));

1627:   isend[0] += info->nz_used;
1628:   isend[1] += info->nz_allocated;
1629:   isend[2] += info->nz_unneeded;
1630:   isend[3] += info->memory;
1631:   isend[4] += info->mallocs;
1632:   if (flag == MAT_LOCAL) {
1633:     info->nz_used      = isend[0];
1634:     info->nz_allocated = isend[1];
1635:     info->nz_unneeded  = isend[2];
1636:     info->memory       = isend[3];
1637:     info->mallocs      = isend[4];
1638:   } else if (flag == MAT_GLOBAL_MAX) {
1639:     PetscCall(MPIU_Allreduce(isend, irecv, 5, MPIU_PETSCLOGDOUBLE, MPI_MAX, PetscObjectComm((PetscObject)matin)));

1641:     info->nz_used      = irecv[0];
1642:     info->nz_allocated = irecv[1];
1643:     info->nz_unneeded  = irecv[2];
1644:     info->memory       = irecv[3];
1645:     info->mallocs      = irecv[4];
1646:   } else if (flag == MAT_GLOBAL_SUM) {
1647:     PetscCall(MPIU_Allreduce(isend, irecv, 5, MPIU_PETSCLOGDOUBLE, MPI_SUM, PetscObjectComm((PetscObject)matin)));

1649:     info->nz_used      = irecv[0];
1650:     info->nz_allocated = irecv[1];
1651:     info->nz_unneeded  = irecv[2];
1652:     info->memory       = irecv[3];
1653:     info->mallocs      = irecv[4];
1654:   }
1655:   info->fill_ratio_given  = 0; /* no parallel LU/ILU/Cholesky */
1656:   info->fill_ratio_needed = 0;
1657:   info->factor_mallocs    = 0;
1658:   PetscFunctionReturn(PETSC_SUCCESS);
1659: }

1661: PetscErrorCode MatSetOption_MPIAIJ(Mat A, MatOption op, PetscBool flg)
1662: {
1663:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1665:   PetscFunctionBegin;
1666:   switch (op) {
1667:   case MAT_NEW_NONZERO_LOCATIONS:
1668:   case MAT_NEW_NONZERO_ALLOCATION_ERR:
1669:   case MAT_UNUSED_NONZERO_LOCATION_ERR:
1670:   case MAT_KEEP_NONZERO_PATTERN:
1671:   case MAT_NEW_NONZERO_LOCATION_ERR:
1672:   case MAT_USE_INODES:
1673:   case MAT_IGNORE_ZERO_ENTRIES:
1674:   case MAT_FORM_EXPLICIT_TRANSPOSE:
1675:     MatCheckPreallocated(A, 1);
1676:     PetscCall(MatSetOption(a->A, op, flg));
1677:     PetscCall(MatSetOption(a->B, op, flg));
1678:     break;
1679:   case MAT_ROW_ORIENTED:
1680:     MatCheckPreallocated(A, 1);
1681:     a->roworiented = flg;

1683:     PetscCall(MatSetOption(a->A, op, flg));
1684:     PetscCall(MatSetOption(a->B, op, flg));
1685:     break;
1686:   case MAT_FORCE_DIAGONAL_ENTRIES:
1687:   case MAT_SORTED_FULL:
1688:     PetscCall(PetscInfo(A, "Option %s ignored\n", MatOptions[op]));
1689:     break;
1690:   case MAT_IGNORE_OFF_PROC_ENTRIES:
1691:     a->donotstash = flg;
1692:     break;
1693:   /* Symmetry flags are handled directly by MatSetOption() and they don't affect preallocation */
1694:   case MAT_SPD:
1695:   case MAT_SYMMETRIC:
1696:   case MAT_STRUCTURALLY_SYMMETRIC:
1697:   case MAT_HERMITIAN:
1698:   case MAT_SYMMETRY_ETERNAL:
1699:   case MAT_STRUCTURAL_SYMMETRY_ETERNAL:
1700:   case MAT_SPD_ETERNAL:
1701:     /* if the diagonal matrix is square it inherits some of the properties above */
1702:     break;
1703:   case MAT_SUBMAT_SINGLEIS:
1704:     A->submat_singleis = flg;
1705:     break;
1706:   case MAT_STRUCTURE_ONLY:
1707:     /* The option is handled directly by MatSetOption() */
1708:     break;
1709:   default:
1710:     SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "unknown option %d", op);
1711:   }
1712:   PetscFunctionReturn(PETSC_SUCCESS);
1713: }

1715: PetscErrorCode MatGetRow_MPIAIJ(Mat matin, PetscInt row, PetscInt *nz, PetscInt **idx, PetscScalar **v)
1716: {
1717:   Mat_MPIAIJ  *mat = (Mat_MPIAIJ *)matin->data;
1718:   PetscScalar *vworkA, *vworkB, **pvA, **pvB, *v_p;
1719:   PetscInt     i, *cworkA, *cworkB, **pcA, **pcB, cstart = matin->cmap->rstart;
1720:   PetscInt     nztot, nzA, nzB, lrow, rstart = matin->rmap->rstart, rend = matin->rmap->rend;
1721:   PetscInt    *cmap, *idx_p;

1723:   PetscFunctionBegin;
1724:   PetscCheck(!mat->getrowactive, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Already active");
1725:   mat->getrowactive = PETSC_TRUE;

1727:   if (!mat->rowvalues && (idx || v)) {
1728:     /*
1729:         allocate enough space to hold information from the longest row.
1730:     */
1731:     Mat_SeqAIJ *Aa = (Mat_SeqAIJ *)mat->A->data, *Ba = (Mat_SeqAIJ *)mat->B->data;
1732:     PetscInt    max = 1, tmp;
1733:     for (i = 0; i < matin->rmap->n; i++) {
1734:       tmp = Aa->i[i + 1] - Aa->i[i] + Ba->i[i + 1] - Ba->i[i];
1735:       if (max < tmp) max = tmp;
1736:     }
1737:     PetscCall(PetscMalloc2(max, &mat->rowvalues, max, &mat->rowindices));
1738:   }

1740:   PetscCheck(row >= rstart && row < rend, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Only local rows");
1741:   lrow = row - rstart;

1743:   pvA = &vworkA;
1744:   pcA = &cworkA;
1745:   pvB = &vworkB;
1746:   pcB = &cworkB;
1747:   if (!v) {
1748:     pvA = NULL;
1749:     pvB = NULL;
1750:   }
1751:   if (!idx) {
1752:     pcA = NULL;
1753:     if (!v) pcB = NULL;
1754:   }
1755:   PetscCall((*mat->A->ops->getrow)(mat->A, lrow, &nzA, pcA, pvA));
1756:   PetscCall((*mat->B->ops->getrow)(mat->B, lrow, &nzB, pcB, pvB));
1757:   nztot = nzA + nzB;

1759:   cmap = mat->garray;
1760:   if (v || idx) {
1761:     if (nztot) {
1762:       /* Sort by increasing column numbers, assuming A and B already sorted */
1763:       PetscInt imark = -1;
1764:       if (v) {
1765:         *v = v_p = mat->rowvalues;
1766:         for (i = 0; i < nzB; i++) {
1767:           if (cmap[cworkB[i]] < cstart) v_p[i] = vworkB[i];
1768:           else break;
1769:         }
1770:         imark = i;
1771:         for (i = 0; i < nzA; i++) v_p[imark + i] = vworkA[i];
1772:         for (i = imark; i < nzB; i++) v_p[nzA + i] = vworkB[i];
1773:       }
1774:       if (idx) {
1775:         *idx = idx_p = mat->rowindices;
1776:         if (imark > -1) {
1777:           for (i = 0; i < imark; i++) idx_p[i] = cmap[cworkB[i]];
1778:         } else {
1779:           for (i = 0; i < nzB; i++) {
1780:             if (cmap[cworkB[i]] < cstart) idx_p[i] = cmap[cworkB[i]];
1781:             else break;
1782:           }
1783:           imark = i;
1784:         }
1785:         for (i = 0; i < nzA; i++) idx_p[imark + i] = cstart + cworkA[i];
1786:         for (i = imark; i < nzB; i++) idx_p[nzA + i] = cmap[cworkB[i]];
1787:       }
1788:     } else {
1789:       if (idx) *idx = NULL;
1790:       if (v) *v = NULL;
1791:     }
1792:   }
1793:   *nz = nztot;
1794:   PetscCall((*mat->A->ops->restorerow)(mat->A, lrow, &nzA, pcA, pvA));
1795:   PetscCall((*mat->B->ops->restorerow)(mat->B, lrow, &nzB, pcB, pvB));
1796:   PetscFunctionReturn(PETSC_SUCCESS);
1797: }

1799: PetscErrorCode MatRestoreRow_MPIAIJ(Mat mat, PetscInt row, PetscInt *nz, PetscInt **idx, PetscScalar **v)
1800: {
1801:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

1803:   PetscFunctionBegin;
1804:   PetscCheck(aij->getrowactive, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "MatGetRow() must be called first");
1805:   aij->getrowactive = PETSC_FALSE;
1806:   PetscFunctionReturn(PETSC_SUCCESS);
1807: }

1809: static PetscErrorCode MatNorm_MPIAIJ(Mat mat, NormType type, PetscReal *norm)
1810: {
1811:   Mat_MPIAIJ      *aij  = (Mat_MPIAIJ *)mat->data;
1812:   Mat_SeqAIJ      *amat = (Mat_SeqAIJ *)aij->A->data, *bmat = (Mat_SeqAIJ *)aij->B->data;
1813:   PetscInt         i, j, cstart = mat->cmap->rstart;
1814:   PetscReal        sum = 0.0;
1815:   const MatScalar *v, *amata, *bmata;

1817:   PetscFunctionBegin;
1818:   if (aij->size == 1) {
1819:     PetscCall(MatNorm(aij->A, type, norm));
1820:   } else {
1821:     PetscCall(MatSeqAIJGetArrayRead(aij->A, &amata));
1822:     PetscCall(MatSeqAIJGetArrayRead(aij->B, &bmata));
1823:     if (type == NORM_FROBENIUS) {
1824:       v = amata;
1825:       for (i = 0; i < amat->nz; i++) {
1826:         sum += PetscRealPart(PetscConj(*v) * (*v));
1827:         v++;
1828:       }
1829:       v = bmata;
1830:       for (i = 0; i < bmat->nz; i++) {
1831:         sum += PetscRealPart(PetscConj(*v) * (*v));
1832:         v++;
1833:       }
1834:       PetscCall(MPIU_Allreduce(&sum, norm, 1, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)mat)));
1835:       *norm = PetscSqrtReal(*norm);
1836:       PetscCall(PetscLogFlops(2.0 * amat->nz + 2.0 * bmat->nz));
1837:     } else if (type == NORM_1) { /* max column norm */
1838:       PetscReal *tmp, *tmp2;
1839:       PetscInt  *jj, *garray = aij->garray;
1840:       PetscCall(PetscCalloc1(mat->cmap->N + 1, &tmp));
1841:       PetscCall(PetscMalloc1(mat->cmap->N + 1, &tmp2));
1842:       *norm = 0.0;
1843:       v     = amata;
1844:       jj    = amat->j;
1845:       for (j = 0; j < amat->nz; j++) {
1846:         tmp[cstart + *jj++] += PetscAbsScalar(*v);
1847:         v++;
1848:       }
1849:       v  = bmata;
1850:       jj = bmat->j;
1851:       for (j = 0; j < bmat->nz; j++) {
1852:         tmp[garray[*jj++]] += PetscAbsScalar(*v);
1853:         v++;
1854:       }
1855:       PetscCall(MPIU_Allreduce(tmp, tmp2, mat->cmap->N, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)mat)));
1856:       for (j = 0; j < mat->cmap->N; j++) {
1857:         if (tmp2[j] > *norm) *norm = tmp2[j];
1858:       }
1859:       PetscCall(PetscFree(tmp));
1860:       PetscCall(PetscFree(tmp2));
1861:       PetscCall(PetscLogFlops(PetscMax(amat->nz + bmat->nz - 1, 0)));
1862:     } else if (type == NORM_INFINITY) { /* max row norm */
1863:       PetscReal ntemp = 0.0;
1864:       for (j = 0; j < aij->A->rmap->n; j++) {
1865:         v   = amata + amat->i[j];
1866:         sum = 0.0;
1867:         for (i = 0; i < amat->i[j + 1] - amat->i[j]; i++) {
1868:           sum += PetscAbsScalar(*v);
1869:           v++;
1870:         }
1871:         v = bmata + bmat->i[j];
1872:         for (i = 0; i < bmat->i[j + 1] - bmat->i[j]; i++) {
1873:           sum += PetscAbsScalar(*v);
1874:           v++;
1875:         }
1876:         if (sum > ntemp) ntemp = sum;
1877:       }
1878:       PetscCall(MPIU_Allreduce(&ntemp, norm, 1, MPIU_REAL, MPIU_MAX, PetscObjectComm((PetscObject)mat)));
1879:       PetscCall(PetscLogFlops(PetscMax(amat->nz + bmat->nz - 1, 0)));
1880:     } else SETERRQ(PetscObjectComm((PetscObject)mat), PETSC_ERR_SUP, "No support for two norm");
1881:     PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &amata));
1882:     PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &bmata));
1883:   }
1884:   PetscFunctionReturn(PETSC_SUCCESS);
1885: }

1887: static PetscErrorCode MatTranspose_MPIAIJ(Mat A, MatReuse reuse, Mat *matout)
1888: {
1889:   Mat_MPIAIJ      *a    = (Mat_MPIAIJ *)A->data, *b;
1890:   Mat_SeqAIJ      *Aloc = (Mat_SeqAIJ *)a->A->data, *Bloc = (Mat_SeqAIJ *)a->B->data, *sub_B_diag;
1891:   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;
1892:   const PetscInt  *ai, *aj, *bi, *bj, *B_diag_i;
1893:   Mat              B, A_diag, *B_diag;
1894:   const MatScalar *pbv, *bv;

1896:   PetscFunctionBegin;
1897:   if (reuse == MAT_REUSE_MATRIX) PetscCall(MatTransposeCheckNonzeroState_Private(A, *matout));
1898:   ma = A->rmap->n;
1899:   na = A->cmap->n;
1900:   mb = a->B->rmap->n;
1901:   nb = a->B->cmap->n;
1902:   ai = Aloc->i;
1903:   aj = Aloc->j;
1904:   bi = Bloc->i;
1905:   bj = Bloc->j;
1906:   if (reuse == MAT_INITIAL_MATRIX || *matout == A) {
1907:     PetscInt            *d_nnz, *g_nnz, *o_nnz;
1908:     PetscSFNode         *oloc;
1909:     PETSC_UNUSED PetscSF sf;

1911:     PetscCall(PetscMalloc4(na, &d_nnz, na, &o_nnz, nb, &g_nnz, nb, &oloc));
1912:     /* compute d_nnz for preallocation */
1913:     PetscCall(PetscArrayzero(d_nnz, na));
1914:     for (i = 0; i < ai[ma]; i++) d_nnz[aj[i]]++;
1915:     /* compute local off-diagonal contributions */
1916:     PetscCall(PetscArrayzero(g_nnz, nb));
1917:     for (i = 0; i < bi[ma]; i++) g_nnz[bj[i]]++;
1918:     /* map those to global */
1919:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1920:     PetscCall(PetscSFSetGraphLayout(sf, A->cmap, nb, NULL, PETSC_USE_POINTER, a->garray));
1921:     PetscCall(PetscSFSetFromOptions(sf));
1922:     PetscCall(PetscArrayzero(o_nnz, na));
1923:     PetscCall(PetscSFReduceBegin(sf, MPIU_INT, g_nnz, o_nnz, MPI_SUM));
1924:     PetscCall(PetscSFReduceEnd(sf, MPIU_INT, g_nnz, o_nnz, MPI_SUM));
1925:     PetscCall(PetscSFDestroy(&sf));

1927:     PetscCall(MatCreate(PetscObjectComm((PetscObject)A), &B));
1928:     PetscCall(MatSetSizes(B, A->cmap->n, A->rmap->n, N, M));
1929:     PetscCall(MatSetBlockSizes(B, PetscAbs(A->cmap->bs), PetscAbs(A->rmap->bs)));
1930:     PetscCall(MatSetType(B, ((PetscObject)A)->type_name));
1931:     PetscCall(MatMPIAIJSetPreallocation(B, 0, d_nnz, 0, o_nnz));
1932:     PetscCall(PetscFree4(d_nnz, o_nnz, g_nnz, oloc));
1933:   } else {
1934:     B = *matout;
1935:     PetscCall(MatSetOption(B, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_TRUE));
1936:   }

1938:   b           = (Mat_MPIAIJ *)B->data;
1939:   A_diag      = a->A;
1940:   B_diag      = &b->A;
1941:   sub_B_diag  = (Mat_SeqAIJ *)(*B_diag)->data;
1942:   A_diag_ncol = A_diag->cmap->N;
1943:   B_diag_ilen = sub_B_diag->ilen;
1944:   B_diag_i    = sub_B_diag->i;

1946:   /* Set ilen for diagonal of B */
1947:   for (i = 0; i < A_diag_ncol; i++) B_diag_ilen[i] = B_diag_i[i + 1] - B_diag_i[i];

1949:   /* Transpose the diagonal part of the matrix. In contrast to the off-diagonal part, this can be done
1950:   very quickly (=without using MatSetValues), because all writes are local. */
1951:   PetscCall(MatTransposeSetPrecursor(A_diag, *B_diag));
1952:   PetscCall(MatTranspose(A_diag, MAT_REUSE_MATRIX, B_diag));

1954:   /* copy over the B part */
1955:   PetscCall(PetscMalloc1(bi[mb], &cols));
1956:   PetscCall(MatSeqAIJGetArrayRead(a->B, &bv));
1957:   pbv = bv;
1958:   row = A->rmap->rstart;
1959:   for (i = 0; i < bi[mb]; i++) cols[i] = a->garray[bj[i]];
1960:   cols_tmp = cols;
1961:   for (i = 0; i < mb; i++) {
1962:     ncol = bi[i + 1] - bi[i];
1963:     PetscCall(MatSetValues(B, ncol, cols_tmp, 1, &row, pbv, INSERT_VALUES));
1964:     row++;
1965:     if (pbv) pbv += ncol;
1966:     if (cols_tmp) cols_tmp += ncol;
1967:   }
1968:   PetscCall(PetscFree(cols));
1969:   PetscCall(MatSeqAIJRestoreArrayRead(a->B, &bv));

1971:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
1972:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
1973:   if (reuse == MAT_INITIAL_MATRIX || reuse == MAT_REUSE_MATRIX) {
1974:     *matout = B;
1975:   } else {
1976:     PetscCall(MatHeaderMerge(A, &B));
1977:   }
1978:   PetscFunctionReturn(PETSC_SUCCESS);
1979: }

1981: static PetscErrorCode MatDiagonalScale_MPIAIJ(Mat mat, Vec ll, Vec rr)
1982: {
1983:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
1984:   Mat         a = aij->A, b = aij->B;
1985:   PetscInt    s1, s2, s3;

1987:   PetscFunctionBegin;
1988:   PetscCall(MatGetLocalSize(mat, &s2, &s3));
1989:   if (rr) {
1990:     PetscCall(VecGetLocalSize(rr, &s1));
1991:     PetscCheck(s1 == s3, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "right vector non-conforming local size");
1992:     /* Overlap communication with computation. */
1993:     PetscCall(VecScatterBegin(aij->Mvctx, rr, aij->lvec, INSERT_VALUES, SCATTER_FORWARD));
1994:   }
1995:   if (ll) {
1996:     PetscCall(VecGetLocalSize(ll, &s1));
1997:     PetscCheck(s1 == s2, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "left vector non-conforming local size");
1998:     PetscUseTypeMethod(b, diagonalscale, ll, NULL);
1999:   }
2000:   /* scale  the diagonal block */
2001:   PetscUseTypeMethod(a, diagonalscale, ll, rr);

2003:   if (rr) {
2004:     /* Do a scatter end and then right scale the off-diagonal block */
2005:     PetscCall(VecScatterEnd(aij->Mvctx, rr, aij->lvec, INSERT_VALUES, SCATTER_FORWARD));
2006:     PetscUseTypeMethod(b, diagonalscale, NULL, aij->lvec);
2007:   }
2008:   PetscFunctionReturn(PETSC_SUCCESS);
2009: }

2011: static PetscErrorCode MatSetUnfactored_MPIAIJ(Mat A)
2012: {
2013:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2015:   PetscFunctionBegin;
2016:   PetscCall(MatSetUnfactored(a->A));
2017:   PetscFunctionReturn(PETSC_SUCCESS);
2018: }

2020: static PetscErrorCode MatEqual_MPIAIJ(Mat A, Mat B, PetscBool *flag)
2021: {
2022:   Mat_MPIAIJ *matB = (Mat_MPIAIJ *)B->data, *matA = (Mat_MPIAIJ *)A->data;
2023:   Mat         a, b, c, d;
2024:   PetscBool   flg;

2026:   PetscFunctionBegin;
2027:   a = matA->A;
2028:   b = matA->B;
2029:   c = matB->A;
2030:   d = matB->B;

2032:   PetscCall(MatEqual(a, c, &flg));
2033:   if (flg) PetscCall(MatEqual(b, d, &flg));
2034:   PetscCall(MPIU_Allreduce(&flg, flag, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)A)));
2035:   PetscFunctionReturn(PETSC_SUCCESS);
2036: }

2038: static PetscErrorCode MatCopy_MPIAIJ(Mat A, Mat B, MatStructure str)
2039: {
2040:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
2041:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;

2043:   PetscFunctionBegin;
2044:   /* If the two matrices don't have the same copy implementation, they aren't compatible for fast copy. */
2045:   if ((str != SAME_NONZERO_PATTERN) || (A->ops->copy != B->ops->copy)) {
2046:     /* because of the column compression in the off-processor part of the matrix a->B,
2047:        the number of columns in a->B and b->B may be different, hence we cannot call
2048:        the MatCopy() directly on the two parts. If need be, we can provide a more
2049:        efficient copy than the MatCopy_Basic() by first uncompressing the a->B matrices
2050:        then copying the submatrices */
2051:     PetscCall(MatCopy_Basic(A, B, str));
2052:   } else {
2053:     PetscCall(MatCopy(a->A, b->A, str));
2054:     PetscCall(MatCopy(a->B, b->B, str));
2055:   }
2056:   PetscCall(PetscObjectStateIncrease((PetscObject)B));
2057:   PetscFunctionReturn(PETSC_SUCCESS);
2058: }

2060: /*
2061:    Computes the number of nonzeros per row needed for preallocation when X and Y
2062:    have different nonzero structure.
2063: */
2064: 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)
2065: {
2066:   PetscInt i, j, k, nzx, nzy;

2068:   PetscFunctionBegin;
2069:   /* Set the number of nonzeros in the new matrix */
2070:   for (i = 0; i < m; i++) {
2071:     const PetscInt *xjj = xj + xi[i], *yjj = yj + yi[i];
2072:     nzx    = xi[i + 1] - xi[i];
2073:     nzy    = yi[i + 1] - yi[i];
2074:     nnz[i] = 0;
2075:     for (j = 0, k = 0; j < nzx; j++) {                                /* Point in X */
2076:       for (; k < nzy && yltog[yjj[k]] < xltog[xjj[j]]; k++) nnz[i]++; /* Catch up to X */
2077:       if (k < nzy && yltog[yjj[k]] == xltog[xjj[j]]) k++;             /* Skip duplicate */
2078:       nnz[i]++;
2079:     }
2080:     for (; k < nzy; k++) nnz[i]++;
2081:   }
2082:   PetscFunctionReturn(PETSC_SUCCESS);
2083: }

2085: /* This is the same as MatAXPYGetPreallocation_SeqAIJ, except that the local-to-global map is provided */
2086: static PetscErrorCode MatAXPYGetPreallocation_MPIAIJ(Mat Y, const PetscInt *yltog, Mat X, const PetscInt *xltog, PetscInt *nnz)
2087: {
2088:   PetscInt    m = Y->rmap->N;
2089:   Mat_SeqAIJ *x = (Mat_SeqAIJ *)X->data;
2090:   Mat_SeqAIJ *y = (Mat_SeqAIJ *)Y->data;

2092:   PetscFunctionBegin;
2093:   PetscCall(MatAXPYGetPreallocation_MPIX_private(m, x->i, x->j, xltog, y->i, y->j, yltog, nnz));
2094:   PetscFunctionReturn(PETSC_SUCCESS);
2095: }

2097: static PetscErrorCode MatAXPY_MPIAIJ(Mat Y, PetscScalar a, Mat X, MatStructure str)
2098: {
2099:   Mat_MPIAIJ *xx = (Mat_MPIAIJ *)X->data, *yy = (Mat_MPIAIJ *)Y->data;

2101:   PetscFunctionBegin;
2102:   if (str == SAME_NONZERO_PATTERN) {
2103:     PetscCall(MatAXPY(yy->A, a, xx->A, str));
2104:     PetscCall(MatAXPY(yy->B, a, xx->B, str));
2105:   } else if (str == SUBSET_NONZERO_PATTERN) { /* nonzeros of X is a subset of Y's */
2106:     PetscCall(MatAXPY_Basic(Y, a, X, str));
2107:   } else {
2108:     Mat       B;
2109:     PetscInt *nnz_d, *nnz_o;

2111:     PetscCall(PetscMalloc1(yy->A->rmap->N, &nnz_d));
2112:     PetscCall(PetscMalloc1(yy->B->rmap->N, &nnz_o));
2113:     PetscCall(MatCreate(PetscObjectComm((PetscObject)Y), &B));
2114:     PetscCall(PetscObjectSetName((PetscObject)B, ((PetscObject)Y)->name));
2115:     PetscCall(MatSetLayouts(B, Y->rmap, Y->cmap));
2116:     PetscCall(MatSetType(B, ((PetscObject)Y)->type_name));
2117:     PetscCall(MatAXPYGetPreallocation_SeqAIJ(yy->A, xx->A, nnz_d));
2118:     PetscCall(MatAXPYGetPreallocation_MPIAIJ(yy->B, yy->garray, xx->B, xx->garray, nnz_o));
2119:     PetscCall(MatMPIAIJSetPreallocation(B, 0, nnz_d, 0, nnz_o));
2120:     PetscCall(MatAXPY_BasicWithPreallocation(B, Y, a, X, str));
2121:     PetscCall(MatHeaderMerge(Y, &B));
2122:     PetscCall(PetscFree(nnz_d));
2123:     PetscCall(PetscFree(nnz_o));
2124:   }
2125:   PetscFunctionReturn(PETSC_SUCCESS);
2126: }

2128: PETSC_INTERN PetscErrorCode MatConjugate_SeqAIJ(Mat);

2130: static PetscErrorCode MatConjugate_MPIAIJ(Mat mat)
2131: {
2132:   PetscFunctionBegin;
2133:   if (PetscDefined(USE_COMPLEX)) {
2134:     Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2136:     PetscCall(MatConjugate_SeqAIJ(aij->A));
2137:     PetscCall(MatConjugate_SeqAIJ(aij->B));
2138:   }
2139:   PetscFunctionReturn(PETSC_SUCCESS);
2140: }

2142: static PetscErrorCode MatRealPart_MPIAIJ(Mat A)
2143: {
2144:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2146:   PetscFunctionBegin;
2147:   PetscCall(MatRealPart(a->A));
2148:   PetscCall(MatRealPart(a->B));
2149:   PetscFunctionReturn(PETSC_SUCCESS);
2150: }

2152: static PetscErrorCode MatImaginaryPart_MPIAIJ(Mat A)
2153: {
2154:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2156:   PetscFunctionBegin;
2157:   PetscCall(MatImaginaryPart(a->A));
2158:   PetscCall(MatImaginaryPart(a->B));
2159:   PetscFunctionReturn(PETSC_SUCCESS);
2160: }

2162: static PetscErrorCode MatGetRowMaxAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2163: {
2164:   Mat_MPIAIJ        *a = (Mat_MPIAIJ *)A->data;
2165:   PetscInt           i, *idxb = NULL, m = A->rmap->n;
2166:   PetscScalar       *va, *vv;
2167:   Vec                vB, vA;
2168:   const PetscScalar *vb;

2170:   PetscFunctionBegin;
2171:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &vA));
2172:   PetscCall(MatGetRowMaxAbs(a->A, vA, idx));

2174:   PetscCall(VecGetArrayWrite(vA, &va));
2175:   if (idx) {
2176:     for (i = 0; i < m; i++) {
2177:       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
2178:     }
2179:   }

2181:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &vB));
2182:   PetscCall(PetscMalloc1(m, &idxb));
2183:   PetscCall(MatGetRowMaxAbs(a->B, vB, idxb));

2185:   PetscCall(VecGetArrayWrite(v, &vv));
2186:   PetscCall(VecGetArrayRead(vB, &vb));
2187:   for (i = 0; i < m; i++) {
2188:     if (PetscAbsScalar(va[i]) < PetscAbsScalar(vb[i])) {
2189:       vv[i] = vb[i];
2190:       if (idx) idx[i] = a->garray[idxb[i]];
2191:     } else {
2192:       vv[i] = va[i];
2193:       if (idx && PetscAbsScalar(va[i]) == PetscAbsScalar(vb[i]) && idxb[i] != -1 && idx[i] > a->garray[idxb[i]]) idx[i] = a->garray[idxb[i]];
2194:     }
2195:   }
2196:   PetscCall(VecRestoreArrayWrite(vA, &vv));
2197:   PetscCall(VecRestoreArrayWrite(vA, &va));
2198:   PetscCall(VecRestoreArrayRead(vB, &vb));
2199:   PetscCall(PetscFree(idxb));
2200:   PetscCall(VecDestroy(&vA));
2201:   PetscCall(VecDestroy(&vB));
2202:   PetscFunctionReturn(PETSC_SUCCESS);
2203: }

2205: static PetscErrorCode MatGetRowMinAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2206: {
2207:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2208:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2209:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2210:   PetscInt          *cmap = mat->garray;
2211:   PetscInt          *diagIdx, *offdiagIdx;
2212:   Vec                diagV, offdiagV;
2213:   PetscScalar       *a, *diagA, *offdiagA;
2214:   const PetscScalar *ba, *bav;
2215:   PetscInt           r, j, col, ncols, *bi, *bj;
2216:   Mat                B = mat->B;
2217:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2219:   PetscFunctionBegin;
2220:   /* When a process holds entire A and other processes have no entry */
2221:   if (A->cmap->N == n) {
2222:     PetscCall(VecGetArrayWrite(v, &diagA));
2223:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2224:     PetscCall(MatGetRowMinAbs(mat->A, diagV, idx));
2225:     PetscCall(VecDestroy(&diagV));
2226:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2227:     PetscFunctionReturn(PETSC_SUCCESS);
2228:   } else if (n == 0) {
2229:     if (m) {
2230:       PetscCall(VecGetArrayWrite(v, &a));
2231:       for (r = 0; r < m; r++) {
2232:         a[r] = 0.0;
2233:         if (idx) idx[r] = -1;
2234:       }
2235:       PetscCall(VecRestoreArrayWrite(v, &a));
2236:     }
2237:     PetscFunctionReturn(PETSC_SUCCESS);
2238:   }

2240:   PetscCall(PetscMalloc2(m, &diagIdx, m, &offdiagIdx));
2241:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2242:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2243:   PetscCall(MatGetRowMinAbs(mat->A, diagV, diagIdx));

2245:   /* Get offdiagIdx[] for implicit 0.0 */
2246:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2247:   ba = bav;
2248:   bi = b->i;
2249:   bj = b->j;
2250:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2251:   for (r = 0; r < m; r++) {
2252:     ncols = bi[r + 1] - bi[r];
2253:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2254:       offdiagA[r]   = *ba;
2255:       offdiagIdx[r] = cmap[0];
2256:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2257:       offdiagA[r] = 0.0;

2259:       /* Find first hole in the cmap */
2260:       for (j = 0; j < ncols; j++) {
2261:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2262:         if (col > j && j < cstart) {
2263:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2264:           break;
2265:         } else if (col > j + n && j >= cstart) {
2266:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2267:           break;
2268:         }
2269:       }
2270:       if (j == ncols && ncols < A->cmap->N - n) {
2271:         /* a hole is outside compressed Bcols */
2272:         if (ncols == 0) {
2273:           if (cstart) {
2274:             offdiagIdx[r] = 0;
2275:           } else offdiagIdx[r] = cend;
2276:         } else { /* ncols > 0 */
2277:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2278:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2279:         }
2280:       }
2281:     }

2283:     for (j = 0; j < ncols; j++) {
2284:       if (PetscAbsScalar(offdiagA[r]) > PetscAbsScalar(*ba)) {
2285:         offdiagA[r]   = *ba;
2286:         offdiagIdx[r] = cmap[*bj];
2287:       }
2288:       ba++;
2289:       bj++;
2290:     }
2291:   }

2293:   PetscCall(VecGetArrayWrite(v, &a));
2294:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2295:   for (r = 0; r < m; ++r) {
2296:     if (PetscAbsScalar(diagA[r]) < PetscAbsScalar(offdiagA[r])) {
2297:       a[r] = diagA[r];
2298:       if (idx) idx[r] = cstart + diagIdx[r];
2299:     } else if (PetscAbsScalar(diagA[r]) == PetscAbsScalar(offdiagA[r])) {
2300:       a[r] = diagA[r];
2301:       if (idx) {
2302:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2303:           idx[r] = cstart + diagIdx[r];
2304:         } else idx[r] = offdiagIdx[r];
2305:       }
2306:     } else {
2307:       a[r] = offdiagA[r];
2308:       if (idx) idx[r] = offdiagIdx[r];
2309:     }
2310:   }
2311:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2312:   PetscCall(VecRestoreArrayWrite(v, &a));
2313:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2314:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2315:   PetscCall(VecDestroy(&diagV));
2316:   PetscCall(VecDestroy(&offdiagV));
2317:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2318:   PetscFunctionReturn(PETSC_SUCCESS);
2319: }

2321: static PetscErrorCode MatGetRowMin_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2322: {
2323:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2324:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2325:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2326:   PetscInt          *cmap = mat->garray;
2327:   PetscInt          *diagIdx, *offdiagIdx;
2328:   Vec                diagV, offdiagV;
2329:   PetscScalar       *a, *diagA, *offdiagA;
2330:   const PetscScalar *ba, *bav;
2331:   PetscInt           r, j, col, ncols, *bi, *bj;
2332:   Mat                B = mat->B;
2333:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2335:   PetscFunctionBegin;
2336:   /* When a process holds entire A and other processes have no entry */
2337:   if (A->cmap->N == n) {
2338:     PetscCall(VecGetArrayWrite(v, &diagA));
2339:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2340:     PetscCall(MatGetRowMin(mat->A, diagV, idx));
2341:     PetscCall(VecDestroy(&diagV));
2342:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2343:     PetscFunctionReturn(PETSC_SUCCESS);
2344:   } else if (n == 0) {
2345:     if (m) {
2346:       PetscCall(VecGetArrayWrite(v, &a));
2347:       for (r = 0; r < m; r++) {
2348:         a[r] = PETSC_MAX_REAL;
2349:         if (idx) idx[r] = -1;
2350:       }
2351:       PetscCall(VecRestoreArrayWrite(v, &a));
2352:     }
2353:     PetscFunctionReturn(PETSC_SUCCESS);
2354:   }

2356:   PetscCall(PetscCalloc2(m, &diagIdx, m, &offdiagIdx));
2357:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2358:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2359:   PetscCall(MatGetRowMin(mat->A, diagV, diagIdx));

2361:   /* Get offdiagIdx[] for implicit 0.0 */
2362:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2363:   ba = bav;
2364:   bi = b->i;
2365:   bj = b->j;
2366:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2367:   for (r = 0; r < m; r++) {
2368:     ncols = bi[r + 1] - bi[r];
2369:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2370:       offdiagA[r]   = *ba;
2371:       offdiagIdx[r] = cmap[0];
2372:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2373:       offdiagA[r] = 0.0;

2375:       /* Find first hole in the cmap */
2376:       for (j = 0; j < ncols; j++) {
2377:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2378:         if (col > j && j < cstart) {
2379:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2380:           break;
2381:         } else if (col > j + n && j >= cstart) {
2382:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2383:           break;
2384:         }
2385:       }
2386:       if (j == ncols && ncols < A->cmap->N - n) {
2387:         /* a hole is outside compressed Bcols */
2388:         if (ncols == 0) {
2389:           if (cstart) {
2390:             offdiagIdx[r] = 0;
2391:           } else offdiagIdx[r] = cend;
2392:         } else { /* ncols > 0 */
2393:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2394:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2395:         }
2396:       }
2397:     }

2399:     for (j = 0; j < ncols; j++) {
2400:       if (PetscRealPart(offdiagA[r]) > PetscRealPart(*ba)) {
2401:         offdiagA[r]   = *ba;
2402:         offdiagIdx[r] = cmap[*bj];
2403:       }
2404:       ba++;
2405:       bj++;
2406:     }
2407:   }

2409:   PetscCall(VecGetArrayWrite(v, &a));
2410:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2411:   for (r = 0; r < m; ++r) {
2412:     if (PetscRealPart(diagA[r]) < PetscRealPart(offdiagA[r])) {
2413:       a[r] = diagA[r];
2414:       if (idx) idx[r] = cstart + diagIdx[r];
2415:     } else if (PetscRealPart(diagA[r]) == PetscRealPart(offdiagA[r])) {
2416:       a[r] = diagA[r];
2417:       if (idx) {
2418:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2419:           idx[r] = cstart + diagIdx[r];
2420:         } else idx[r] = offdiagIdx[r];
2421:       }
2422:     } else {
2423:       a[r] = offdiagA[r];
2424:       if (idx) idx[r] = offdiagIdx[r];
2425:     }
2426:   }
2427:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2428:   PetscCall(VecRestoreArrayWrite(v, &a));
2429:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2430:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2431:   PetscCall(VecDestroy(&diagV));
2432:   PetscCall(VecDestroy(&offdiagV));
2433:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2434:   PetscFunctionReturn(PETSC_SUCCESS);
2435: }

2437: static PetscErrorCode MatGetRowMax_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2438: {
2439:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2440:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2441:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2442:   PetscInt          *cmap = mat->garray;
2443:   PetscInt          *diagIdx, *offdiagIdx;
2444:   Vec                diagV, offdiagV;
2445:   PetscScalar       *a, *diagA, *offdiagA;
2446:   const PetscScalar *ba, *bav;
2447:   PetscInt           r, j, col, ncols, *bi, *bj;
2448:   Mat                B = mat->B;
2449:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2451:   PetscFunctionBegin;
2452:   /* When a process holds entire A and other processes have no entry */
2453:   if (A->cmap->N == n) {
2454:     PetscCall(VecGetArrayWrite(v, &diagA));
2455:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2456:     PetscCall(MatGetRowMax(mat->A, diagV, idx));
2457:     PetscCall(VecDestroy(&diagV));
2458:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2459:     PetscFunctionReturn(PETSC_SUCCESS);
2460:   } else if (n == 0) {
2461:     if (m) {
2462:       PetscCall(VecGetArrayWrite(v, &a));
2463:       for (r = 0; r < m; r++) {
2464:         a[r] = PETSC_MIN_REAL;
2465:         if (idx) idx[r] = -1;
2466:       }
2467:       PetscCall(VecRestoreArrayWrite(v, &a));
2468:     }
2469:     PetscFunctionReturn(PETSC_SUCCESS);
2470:   }

2472:   PetscCall(PetscMalloc2(m, &diagIdx, m, &offdiagIdx));
2473:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2474:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2475:   PetscCall(MatGetRowMax(mat->A, diagV, diagIdx));

2477:   /* Get offdiagIdx[] for implicit 0.0 */
2478:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2479:   ba = bav;
2480:   bi = b->i;
2481:   bj = b->j;
2482:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2483:   for (r = 0; r < m; r++) {
2484:     ncols = bi[r + 1] - bi[r];
2485:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2486:       offdiagA[r]   = *ba;
2487:       offdiagIdx[r] = cmap[0];
2488:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2489:       offdiagA[r] = 0.0;

2491:       /* Find first hole in the cmap */
2492:       for (j = 0; j < ncols; j++) {
2493:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2494:         if (col > j && j < cstart) {
2495:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2496:           break;
2497:         } else if (col > j + n && j >= cstart) {
2498:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2499:           break;
2500:         }
2501:       }
2502:       if (j == ncols && ncols < A->cmap->N - n) {
2503:         /* a hole is outside compressed Bcols */
2504:         if (ncols == 0) {
2505:           if (cstart) {
2506:             offdiagIdx[r] = 0;
2507:           } else offdiagIdx[r] = cend;
2508:         } else { /* ncols > 0 */
2509:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2510:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2511:         }
2512:       }
2513:     }

2515:     for (j = 0; j < ncols; j++) {
2516:       if (PetscRealPart(offdiagA[r]) < PetscRealPart(*ba)) {
2517:         offdiagA[r]   = *ba;
2518:         offdiagIdx[r] = cmap[*bj];
2519:       }
2520:       ba++;
2521:       bj++;
2522:     }
2523:   }

2525:   PetscCall(VecGetArrayWrite(v, &a));
2526:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2527:   for (r = 0; r < m; ++r) {
2528:     if (PetscRealPart(diagA[r]) > PetscRealPart(offdiagA[r])) {
2529:       a[r] = diagA[r];
2530:       if (idx) idx[r] = cstart + diagIdx[r];
2531:     } else if (PetscRealPart(diagA[r]) == PetscRealPart(offdiagA[r])) {
2532:       a[r] = diagA[r];
2533:       if (idx) {
2534:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2535:           idx[r] = cstart + diagIdx[r];
2536:         } else idx[r] = offdiagIdx[r];
2537:       }
2538:     } else {
2539:       a[r] = offdiagA[r];
2540:       if (idx) idx[r] = offdiagIdx[r];
2541:     }
2542:   }
2543:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2544:   PetscCall(VecRestoreArrayWrite(v, &a));
2545:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2546:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2547:   PetscCall(VecDestroy(&diagV));
2548:   PetscCall(VecDestroy(&offdiagV));
2549:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2550:   PetscFunctionReturn(PETSC_SUCCESS);
2551: }

2553: PetscErrorCode MatGetSeqNonzeroStructure_MPIAIJ(Mat mat, Mat *newmat)
2554: {
2555:   Mat *dummy;

2557:   PetscFunctionBegin;
2558:   PetscCall(MatCreateSubMatrix_MPIAIJ_All(mat, MAT_DO_NOT_GET_VALUES, MAT_INITIAL_MATRIX, &dummy));
2559:   *newmat = *dummy;
2560:   PetscCall(PetscFree(dummy));
2561:   PetscFunctionReturn(PETSC_SUCCESS);
2562: }

2564: static PetscErrorCode MatInvertBlockDiagonal_MPIAIJ(Mat A, const PetscScalar **values)
2565: {
2566:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2568:   PetscFunctionBegin;
2569:   PetscCall(MatInvertBlockDiagonal(a->A, values));
2570:   A->factorerrortype = a->A->factorerrortype;
2571:   PetscFunctionReturn(PETSC_SUCCESS);
2572: }

2574: static PetscErrorCode MatSetRandom_MPIAIJ(Mat x, PetscRandom rctx)
2575: {
2576:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)x->data;

2578:   PetscFunctionBegin;
2579:   PetscCheck(x->assembled || x->preallocated, PetscObjectComm((PetscObject)x), PETSC_ERR_ARG_WRONGSTATE, "MatSetRandom on an unassembled and unpreallocated MATMPIAIJ is not allowed");
2580:   PetscCall(MatSetRandom(aij->A, rctx));
2581:   if (x->assembled) {
2582:     PetscCall(MatSetRandom(aij->B, rctx));
2583:   } else {
2584:     PetscCall(MatSetRandomSkipColumnRange_SeqAIJ_Private(aij->B, x->cmap->rstart, x->cmap->rend, rctx));
2585:   }
2586:   PetscCall(MatAssemblyBegin(x, MAT_FINAL_ASSEMBLY));
2587:   PetscCall(MatAssemblyEnd(x, MAT_FINAL_ASSEMBLY));
2588:   PetscFunctionReturn(PETSC_SUCCESS);
2589: }

2591: static PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ(Mat A, PetscBool sc)
2592: {
2593:   PetscFunctionBegin;
2594:   if (sc) A->ops->increaseoverlap = MatIncreaseOverlap_MPIAIJ_Scalable;
2595:   else A->ops->increaseoverlap = MatIncreaseOverlap_MPIAIJ;
2596:   PetscFunctionReturn(PETSC_SUCCESS);
2597: }

2599: /*@
2600:   MatMPIAIJGetNumberNonzeros - gets the number of nonzeros in the matrix on this MPI rank

2602:   Not Collective

2604:   Input Parameter:
2605: . A - the matrix

2607:   Output Parameter:
2608: . nz - the number of nonzeros

2610:   Level: advanced

2612: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`
2613: @*/
2614: PetscErrorCode MatMPIAIJGetNumberNonzeros(Mat A, PetscCount *nz)
2615: {
2616:   Mat_MPIAIJ *maij = (Mat_MPIAIJ *)A->data;
2617:   Mat_SeqAIJ *aaij = (Mat_SeqAIJ *)maij->A->data, *baij = (Mat_SeqAIJ *)maij->B->data;
2618:   PetscBool   isaij;

2620:   PetscFunctionBegin;
2621:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)A, MATMPIAIJ, &isaij));
2622:   PetscCheck(isaij, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Not for type %s", ((PetscObject)A)->type_name);
2623:   *nz = aaij->i[A->rmap->n] + baij->i[A->rmap->n];
2624:   PetscFunctionReturn(PETSC_SUCCESS);
2625: }

2627: /*@
2628:   MatMPIAIJSetUseScalableIncreaseOverlap - Determine if the matrix uses a scalable algorithm to compute the overlap

2630:   Collective

2632:   Input Parameters:
2633: + A  - the matrix
2634: - sc - `PETSC_TRUE` indicates use the scalable algorithm (default is not to use the scalable algorithm)

2636:   Level: advanced

2638: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`
2639: @*/
2640: PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap(Mat A, PetscBool sc)
2641: {
2642:   PetscFunctionBegin;
2643:   PetscTryMethod(A, "MatMPIAIJSetUseScalableIncreaseOverlap_C", (Mat, PetscBool), (A, sc));
2644:   PetscFunctionReturn(PETSC_SUCCESS);
2645: }

2647: PetscErrorCode MatSetFromOptions_MPIAIJ(Mat A, PetscOptionItems *PetscOptionsObject)
2648: {
2649:   PetscBool sc = PETSC_FALSE, flg;

2651:   PetscFunctionBegin;
2652:   PetscOptionsHeadBegin(PetscOptionsObject, "MPIAIJ options");
2653:   if (A->ops->increaseoverlap == MatIncreaseOverlap_MPIAIJ_Scalable) sc = PETSC_TRUE;
2654:   PetscCall(PetscOptionsBool("-mat_increase_overlap_scalable", "Use a scalable algorithm to compute the overlap", "MatIncreaseOverlap", sc, &sc, &flg));
2655:   if (flg) PetscCall(MatMPIAIJSetUseScalableIncreaseOverlap(A, sc));
2656:   PetscOptionsHeadEnd();
2657:   PetscFunctionReturn(PETSC_SUCCESS);
2658: }

2660: static PetscErrorCode MatShift_MPIAIJ(Mat Y, PetscScalar a)
2661: {
2662:   Mat_MPIAIJ *maij = (Mat_MPIAIJ *)Y->data;
2663:   Mat_SeqAIJ *aij  = (Mat_SeqAIJ *)maij->A->data;

2665:   PetscFunctionBegin;
2666:   if (!Y->preallocated) {
2667:     PetscCall(MatMPIAIJSetPreallocation(Y, 1, NULL, 0, NULL));
2668:   } else if (!aij->nz) { /* It does not matter if diagonals of Y only partially lie in maij->A. We just need an estimated preallocation. */
2669:     PetscInt nonew = aij->nonew;
2670:     PetscCall(MatSeqAIJSetPreallocation(maij->A, 1, NULL));
2671:     aij->nonew = nonew;
2672:   }
2673:   PetscCall(MatShift_Basic(Y, a));
2674:   PetscFunctionReturn(PETSC_SUCCESS);
2675: }

2677: static PetscErrorCode MatMissingDiagonal_MPIAIJ(Mat A, PetscBool *missing, PetscInt *d)
2678: {
2679:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2681:   PetscFunctionBegin;
2682:   PetscCheck(A->rmap->n == A->cmap->n, PETSC_COMM_SELF, PETSC_ERR_SUP, "Only works for square matrices");
2683:   PetscCall(MatMissingDiagonal(a->A, missing, d));
2684:   if (d) {
2685:     PetscInt rstart;
2686:     PetscCall(MatGetOwnershipRange(A, &rstart, NULL));
2687:     *d += rstart;
2688:   }
2689:   PetscFunctionReturn(PETSC_SUCCESS);
2690: }

2692: static PetscErrorCode MatInvertVariableBlockDiagonal_MPIAIJ(Mat A, PetscInt nblocks, const PetscInt *bsizes, PetscScalar *diag)
2693: {
2694:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2696:   PetscFunctionBegin;
2697:   PetscCall(MatInvertVariableBlockDiagonal(a->A, nblocks, bsizes, diag));
2698:   PetscFunctionReturn(PETSC_SUCCESS);
2699: }

2701: static PetscErrorCode MatEliminateZeros_MPIAIJ(Mat A, PetscBool keep)
2702: {
2703:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2705:   PetscFunctionBegin;
2706:   PetscCall(MatEliminateZeros_SeqAIJ(a->A, keep));        // possibly keep zero diagonal coefficients
2707:   PetscCall(MatEliminateZeros_SeqAIJ(a->B, PETSC_FALSE)); // never keep zero diagonal coefficients
2708:   PetscFunctionReturn(PETSC_SUCCESS);
2709: }

2711: static struct _MatOps MatOps_Values = {MatSetValues_MPIAIJ,
2712:                                        MatGetRow_MPIAIJ,
2713:                                        MatRestoreRow_MPIAIJ,
2714:                                        MatMult_MPIAIJ,
2715:                                        /* 4*/ MatMultAdd_MPIAIJ,
2716:                                        MatMultTranspose_MPIAIJ,
2717:                                        MatMultTransposeAdd_MPIAIJ,
2718:                                        NULL,
2719:                                        NULL,
2720:                                        NULL,
2721:                                        /*10*/ NULL,
2722:                                        NULL,
2723:                                        NULL,
2724:                                        MatSOR_MPIAIJ,
2725:                                        MatTranspose_MPIAIJ,
2726:                                        /*15*/ MatGetInfo_MPIAIJ,
2727:                                        MatEqual_MPIAIJ,
2728:                                        MatGetDiagonal_MPIAIJ,
2729:                                        MatDiagonalScale_MPIAIJ,
2730:                                        MatNorm_MPIAIJ,
2731:                                        /*20*/ MatAssemblyBegin_MPIAIJ,
2732:                                        MatAssemblyEnd_MPIAIJ,
2733:                                        MatSetOption_MPIAIJ,
2734:                                        MatZeroEntries_MPIAIJ,
2735:                                        /*24*/ MatZeroRows_MPIAIJ,
2736:                                        NULL,
2737:                                        NULL,
2738:                                        NULL,
2739:                                        NULL,
2740:                                        /*29*/ MatSetUp_MPI_Hash,
2741:                                        NULL,
2742:                                        NULL,
2743:                                        MatGetDiagonalBlock_MPIAIJ,
2744:                                        NULL,
2745:                                        /*34*/ MatDuplicate_MPIAIJ,
2746:                                        NULL,
2747:                                        NULL,
2748:                                        NULL,
2749:                                        NULL,
2750:                                        /*39*/ MatAXPY_MPIAIJ,
2751:                                        MatCreateSubMatrices_MPIAIJ,
2752:                                        MatIncreaseOverlap_MPIAIJ,
2753:                                        MatGetValues_MPIAIJ,
2754:                                        MatCopy_MPIAIJ,
2755:                                        /*44*/ MatGetRowMax_MPIAIJ,
2756:                                        MatScale_MPIAIJ,
2757:                                        MatShift_MPIAIJ,
2758:                                        MatDiagonalSet_MPIAIJ,
2759:                                        MatZeroRowsColumns_MPIAIJ,
2760:                                        /*49*/ MatSetRandom_MPIAIJ,
2761:                                        MatGetRowIJ_MPIAIJ,
2762:                                        MatRestoreRowIJ_MPIAIJ,
2763:                                        NULL,
2764:                                        NULL,
2765:                                        /*54*/ MatFDColoringCreate_MPIXAIJ,
2766:                                        NULL,
2767:                                        MatSetUnfactored_MPIAIJ,
2768:                                        MatPermute_MPIAIJ,
2769:                                        NULL,
2770:                                        /*59*/ MatCreateSubMatrix_MPIAIJ,
2771:                                        MatDestroy_MPIAIJ,
2772:                                        MatView_MPIAIJ,
2773:                                        NULL,
2774:                                        NULL,
2775:                                        /*64*/ NULL,
2776:                                        MatMatMatMultNumeric_MPIAIJ_MPIAIJ_MPIAIJ,
2777:                                        NULL,
2778:                                        NULL,
2779:                                        NULL,
2780:                                        /*69*/ MatGetRowMaxAbs_MPIAIJ,
2781:                                        MatGetRowMinAbs_MPIAIJ,
2782:                                        NULL,
2783:                                        NULL,
2784:                                        NULL,
2785:                                        NULL,
2786:                                        /*75*/ MatFDColoringApply_AIJ,
2787:                                        MatSetFromOptions_MPIAIJ,
2788:                                        NULL,
2789:                                        NULL,
2790:                                        MatFindZeroDiagonals_MPIAIJ,
2791:                                        /*80*/ NULL,
2792:                                        NULL,
2793:                                        NULL,
2794:                                        /*83*/ MatLoad_MPIAIJ,
2795:                                        MatIsSymmetric_MPIAIJ,
2796:                                        NULL,
2797:                                        NULL,
2798:                                        NULL,
2799:                                        NULL,
2800:                                        /*89*/ NULL,
2801:                                        NULL,
2802:                                        MatMatMultNumeric_MPIAIJ_MPIAIJ,
2803:                                        NULL,
2804:                                        NULL,
2805:                                        /*94*/ MatPtAPNumeric_MPIAIJ_MPIAIJ,
2806:                                        NULL,
2807:                                        NULL,
2808:                                        NULL,
2809:                                        MatBindToCPU_MPIAIJ,
2810:                                        /*99*/ MatProductSetFromOptions_MPIAIJ,
2811:                                        NULL,
2812:                                        NULL,
2813:                                        MatConjugate_MPIAIJ,
2814:                                        NULL,
2815:                                        /*104*/ MatSetValuesRow_MPIAIJ,
2816:                                        MatRealPart_MPIAIJ,
2817:                                        MatImaginaryPart_MPIAIJ,
2818:                                        NULL,
2819:                                        NULL,
2820:                                        /*109*/ NULL,
2821:                                        NULL,
2822:                                        MatGetRowMin_MPIAIJ,
2823:                                        NULL,
2824:                                        MatMissingDiagonal_MPIAIJ,
2825:                                        /*114*/ MatGetSeqNonzeroStructure_MPIAIJ,
2826:                                        NULL,
2827:                                        MatGetGhosts_MPIAIJ,
2828:                                        NULL,
2829:                                        NULL,
2830:                                        /*119*/ MatMultDiagonalBlock_MPIAIJ,
2831:                                        NULL,
2832:                                        NULL,
2833:                                        NULL,
2834:                                        MatGetMultiProcBlock_MPIAIJ,
2835:                                        /*124*/ MatFindNonzeroRows_MPIAIJ,
2836:                                        MatGetColumnReductions_MPIAIJ,
2837:                                        MatInvertBlockDiagonal_MPIAIJ,
2838:                                        MatInvertVariableBlockDiagonal_MPIAIJ,
2839:                                        MatCreateSubMatricesMPI_MPIAIJ,
2840:                                        /*129*/ NULL,
2841:                                        NULL,
2842:                                        NULL,
2843:                                        MatTransposeMatMultNumeric_MPIAIJ_MPIAIJ,
2844:                                        NULL,
2845:                                        /*134*/ NULL,
2846:                                        NULL,
2847:                                        NULL,
2848:                                        NULL,
2849:                                        NULL,
2850:                                        /*139*/ MatSetBlockSizes_MPIAIJ,
2851:                                        NULL,
2852:                                        NULL,
2853:                                        MatFDColoringSetUp_MPIXAIJ,
2854:                                        MatFindOffBlockDiagonalEntries_MPIAIJ,
2855:                                        MatCreateMPIMatConcatenateSeqMat_MPIAIJ,
2856:                                        /*145*/ NULL,
2857:                                        NULL,
2858:                                        NULL,
2859:                                        MatCreateGraph_Simple_AIJ,
2860:                                        NULL,
2861:                                        /*150*/ NULL,
2862:                                        MatEliminateZeros_MPIAIJ};

2864: static PetscErrorCode MatStoreValues_MPIAIJ(Mat mat)
2865: {
2866:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2868:   PetscFunctionBegin;
2869:   PetscCall(MatStoreValues(aij->A));
2870:   PetscCall(MatStoreValues(aij->B));
2871:   PetscFunctionReturn(PETSC_SUCCESS);
2872: }

2874: static PetscErrorCode MatRetrieveValues_MPIAIJ(Mat mat)
2875: {
2876:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2878:   PetscFunctionBegin;
2879:   PetscCall(MatRetrieveValues(aij->A));
2880:   PetscCall(MatRetrieveValues(aij->B));
2881:   PetscFunctionReturn(PETSC_SUCCESS);
2882: }

2884: PetscErrorCode MatMPIAIJSetPreallocation_MPIAIJ(Mat B, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[])
2885: {
2886:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;
2887:   PetscMPIInt size;

2889:   PetscFunctionBegin;
2890:   if (B->hash_active) {
2891:     B->ops[0]      = b->cops;
2892:     B->hash_active = PETSC_FALSE;
2893:   }
2894:   PetscCall(PetscLayoutSetUp(B->rmap));
2895:   PetscCall(PetscLayoutSetUp(B->cmap));

2897: #if defined(PETSC_USE_CTABLE)
2898:   PetscCall(PetscHMapIDestroy(&b->colmap));
2899: #else
2900:   PetscCall(PetscFree(b->colmap));
2901: #endif
2902:   PetscCall(PetscFree(b->garray));
2903:   PetscCall(VecDestroy(&b->lvec));
2904:   PetscCall(VecScatterDestroy(&b->Mvctx));

2906:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)B), &size));
2907:   PetscCall(MatDestroy(&b->B));
2908:   PetscCall(MatCreate(PETSC_COMM_SELF, &b->B));
2909:   PetscCall(MatSetSizes(b->B, B->rmap->n, size > 1 ? B->cmap->N : 0, B->rmap->n, size > 1 ? B->cmap->N : 0));
2910:   PetscCall(MatSetBlockSizesFromMats(b->B, B, B));
2911:   PetscCall(MatSetType(b->B, MATSEQAIJ));

2913:   PetscCall(MatDestroy(&b->A));
2914:   PetscCall(MatCreate(PETSC_COMM_SELF, &b->A));
2915:   PetscCall(MatSetSizes(b->A, B->rmap->n, B->cmap->n, B->rmap->n, B->cmap->n));
2916:   PetscCall(MatSetBlockSizesFromMats(b->A, B, B));
2917:   PetscCall(MatSetType(b->A, MATSEQAIJ));

2919:   PetscCall(MatSeqAIJSetPreallocation(b->A, d_nz, d_nnz));
2920:   PetscCall(MatSeqAIJSetPreallocation(b->B, o_nz, o_nnz));
2921:   B->preallocated  = PETSC_TRUE;
2922:   B->was_assembled = PETSC_FALSE;
2923:   B->assembled     = PETSC_FALSE;
2924:   PetscFunctionReturn(PETSC_SUCCESS);
2925: }

2927: static PetscErrorCode MatResetPreallocation_MPIAIJ(Mat B)
2928: {
2929:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;

2931:   PetscFunctionBegin;
2933:   PetscCall(PetscLayoutSetUp(B->rmap));
2934:   PetscCall(PetscLayoutSetUp(B->cmap));

2936: #if defined(PETSC_USE_CTABLE)
2937:   PetscCall(PetscHMapIDestroy(&b->colmap));
2938: #else
2939:   PetscCall(PetscFree(b->colmap));
2940: #endif
2941:   PetscCall(PetscFree(b->garray));
2942:   PetscCall(VecDestroy(&b->lvec));
2943:   PetscCall(VecScatterDestroy(&b->Mvctx));

2945:   PetscCall(MatResetPreallocation(b->A));
2946:   PetscCall(MatResetPreallocation(b->B));
2947:   B->preallocated  = PETSC_TRUE;
2948:   B->was_assembled = PETSC_FALSE;
2949:   B->assembled     = PETSC_FALSE;
2950:   PetscFunctionReturn(PETSC_SUCCESS);
2951: }

2953: PetscErrorCode MatDuplicate_MPIAIJ(Mat matin, MatDuplicateOption cpvalues, Mat *newmat)
2954: {
2955:   Mat         mat;
2956:   Mat_MPIAIJ *a, *oldmat = (Mat_MPIAIJ *)matin->data;

2958:   PetscFunctionBegin;
2959:   *newmat = NULL;
2960:   PetscCall(MatCreate(PetscObjectComm((PetscObject)matin), &mat));
2961:   PetscCall(MatSetSizes(mat, matin->rmap->n, matin->cmap->n, matin->rmap->N, matin->cmap->N));
2962:   PetscCall(MatSetBlockSizesFromMats(mat, matin, matin));
2963:   PetscCall(MatSetType(mat, ((PetscObject)matin)->type_name));
2964:   a = (Mat_MPIAIJ *)mat->data;

2966:   mat->factortype   = matin->factortype;
2967:   mat->assembled    = matin->assembled;
2968:   mat->insertmode   = NOT_SET_VALUES;
2969:   mat->preallocated = matin->preallocated;

2971:   a->size         = oldmat->size;
2972:   a->rank         = oldmat->rank;
2973:   a->donotstash   = oldmat->donotstash;
2974:   a->roworiented  = oldmat->roworiented;
2975:   a->rowindices   = NULL;
2976:   a->rowvalues    = NULL;
2977:   a->getrowactive = PETSC_FALSE;

2979:   PetscCall(PetscLayoutReference(matin->rmap, &mat->rmap));
2980:   PetscCall(PetscLayoutReference(matin->cmap, &mat->cmap));

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 + 1, &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) PetscCall(VecScatterCopy(oldmat->Mvctx, &a->Mvctx));
3002:   PetscCall(MatDuplicate(oldmat->A, cpvalues, &a->A));
3003:   PetscCall(MatDuplicate(oldmat->B, cpvalues, &a->B));
3004:   PetscCall(PetscFunctionListDuplicate(((PetscObject)matin)->qlist, &((PetscObject)mat)->qlist));
3005:   *newmat = mat;
3006:   PetscFunctionReturn(PETSC_SUCCESS);
3007: }

3009: PetscErrorCode MatLoad_MPIAIJ(Mat newMat, PetscViewer viewer)
3010: {
3011:   PetscBool isbinary, ishdf5;

3013:   PetscFunctionBegin;
3016:   /* force binary viewer to load .info file if it has not yet done so */
3017:   PetscCall(PetscViewerSetUp(viewer));
3018:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
3019:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERHDF5, &ishdf5));
3020:   if (isbinary) {
3021:     PetscCall(MatLoad_MPIAIJ_Binary(newMat, viewer));
3022:   } else if (ishdf5) {
3023: #if defined(PETSC_HAVE_HDF5)
3024:     PetscCall(MatLoad_AIJ_HDF5(newMat, viewer));
3025: #else
3026:     SETERRQ(PetscObjectComm((PetscObject)newMat), PETSC_ERR_SUP, "HDF5 not supported in this build.\nPlease reconfigure using --download-hdf5");
3027: #endif
3028:   } else {
3029:     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);
3030:   }
3031:   PetscFunctionReturn(PETSC_SUCCESS);
3032: }

3034: PetscErrorCode MatLoad_MPIAIJ_Binary(Mat mat, PetscViewer viewer)
3035: {
3036:   PetscInt     header[4], M, N, m, nz, rows, cols, sum, i;
3037:   PetscInt    *rowidxs, *colidxs;
3038:   PetscScalar *matvals;

3040:   PetscFunctionBegin;
3041:   PetscCall(PetscViewerSetUp(viewer));

3043:   /* read in matrix header */
3044:   PetscCall(PetscViewerBinaryRead(viewer, header, 4, NULL, PETSC_INT));
3045:   PetscCheck(header[0] == MAT_FILE_CLASSID, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Not a matrix object in file");
3046:   M  = header[1];
3047:   N  = header[2];
3048:   nz = header[3];
3049:   PetscCheck(M >= 0, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Matrix row size (%" PetscInt_FMT ") in file is negative", M);
3050:   PetscCheck(N >= 0, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Matrix column size (%" PetscInt_FMT ") in file is negative", N);
3051:   PetscCheck(nz >= 0, PETSC_COMM_SELF, PETSC_ERR_FILE_UNEXPECTED, "Matrix stored in special format on disk, cannot load as MPIAIJ");

3053:   /* set block sizes from the viewer's .info file */
3054:   PetscCall(MatLoad_Binary_BlockSizes(mat, viewer));
3055:   /* set global sizes if not set already */
3056:   if (mat->rmap->N < 0) mat->rmap->N = M;
3057:   if (mat->cmap->N < 0) mat->cmap->N = N;
3058:   PetscCall(PetscLayoutSetUp(mat->rmap));
3059:   PetscCall(PetscLayoutSetUp(mat->cmap));

3061:   /* check if the matrix sizes are correct */
3062:   PetscCall(MatGetSize(mat, &rows, &cols));
3063:   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);

3065:   /* read in row lengths and build row indices */
3066:   PetscCall(MatGetLocalSize(mat, &m, NULL));
3067:   PetscCall(PetscMalloc1(m + 1, &rowidxs));
3068:   PetscCall(PetscViewerBinaryReadAll(viewer, rowidxs + 1, m, PETSC_DECIDE, M, PETSC_INT));
3069:   rowidxs[0] = 0;
3070:   for (i = 0; i < m; i++) rowidxs[i + 1] += rowidxs[i];
3071:   if (nz != PETSC_MAX_INT) {
3072:     PetscCall(MPIU_Allreduce(&rowidxs[m], &sum, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)viewer)));
3073:     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);
3074:   }

3076:   /* read in column indices and matrix values */
3077:   PetscCall(PetscMalloc2(rowidxs[m], &colidxs, rowidxs[m], &matvals));
3078:   PetscCall(PetscViewerBinaryReadAll(viewer, colidxs, rowidxs[m], PETSC_DETERMINE, PETSC_DETERMINE, PETSC_INT));
3079:   PetscCall(PetscViewerBinaryReadAll(viewer, matvals, rowidxs[m], PETSC_DETERMINE, PETSC_DETERMINE, PETSC_SCALAR));
3080:   /* store matrix indices and values */
3081:   PetscCall(MatMPIAIJSetPreallocationCSR(mat, rowidxs, colidxs, matvals));
3082:   PetscCall(PetscFree(rowidxs));
3083:   PetscCall(PetscFree2(colidxs, matvals));
3084:   PetscFunctionReturn(PETSC_SUCCESS);
3085: }

3087: /* Not scalable because of ISAllGather() unless getting all columns. */
3088: static PetscErrorCode ISGetSeqIS_Private(Mat mat, IS iscol, IS *isseq)
3089: {
3090:   IS          iscol_local;
3091:   PetscBool   isstride;
3092:   PetscMPIInt lisstride = 0, gisstride;

3094:   PetscFunctionBegin;
3095:   /* check if we are grabbing all columns*/
3096:   PetscCall(PetscObjectTypeCompare((PetscObject)iscol, ISSTRIDE, &isstride));

3098:   if (isstride) {
3099:     PetscInt start, len, mstart, mlen;
3100:     PetscCall(ISStrideGetInfo(iscol, &start, NULL));
3101:     PetscCall(ISGetLocalSize(iscol, &len));
3102:     PetscCall(MatGetOwnershipRangeColumn(mat, &mstart, &mlen));
3103:     if (mstart == start && mlen - mstart == len) lisstride = 1;
3104:   }

3106:   PetscCall(MPIU_Allreduce(&lisstride, &gisstride, 1, MPI_INT, MPI_MIN, PetscObjectComm((PetscObject)mat)));
3107:   if (gisstride) {
3108:     PetscInt N;
3109:     PetscCall(MatGetSize(mat, NULL, &N));
3110:     PetscCall(ISCreateStride(PETSC_COMM_SELF, N, 0, 1, &iscol_local));
3111:     PetscCall(ISSetIdentity(iscol_local));
3112:     PetscCall(PetscInfo(mat, "Optimizing for obtaining all columns of the matrix; skipping ISAllGather()\n"));
3113:   } else {
3114:     PetscInt cbs;
3115:     PetscCall(ISGetBlockSize(iscol, &cbs));
3116:     PetscCall(ISAllGather(iscol, &iscol_local));
3117:     PetscCall(ISSetBlockSize(iscol_local, cbs));
3118:   }

3120:   *isseq = iscol_local;
3121:   PetscFunctionReturn(PETSC_SUCCESS);
3122: }

3124: /*
3125:  Used by MatCreateSubMatrix_MPIAIJ_SameRowColDist() to avoid ISAllGather() and global size of iscol_local
3126:  (see MatCreateSubMatrix_MPIAIJ_nonscalable)

3128:  Input Parameters:
3129: +   mat - matrix
3130: .   isrow - parallel row index set; its local indices are a subset of local columns of `mat`,
3131:            i.e., mat->rstart <= isrow[i] < mat->rend
3132: -   iscol - parallel column index set; its local indices are a subset of local columns of `mat`,
3133:            i.e., mat->cstart <= iscol[i] < mat->cend

3135:  Output Parameters:
3136: +   isrow_d - sequential row index set for retrieving mat->A
3137: .   iscol_d - sequential  column index set for retrieving mat->A
3138: .   iscol_o - sequential column index set for retrieving mat->B
3139: -   garray - column map; garray[i] indicates global location of iscol_o[i] in `iscol`
3140:  */
3141: static PetscErrorCode ISGetSeqIS_SameColDist_Private(Mat mat, IS isrow, IS iscol, IS *isrow_d, IS *iscol_d, IS *iscol_o, const PetscInt *garray[])
3142: {
3143:   Vec             x, cmap;
3144:   const PetscInt *is_idx;
3145:   PetscScalar    *xarray, *cmaparray;
3146:   PetscInt        ncols, isstart, *idx, m, rstart, *cmap1, count;
3147:   Mat_MPIAIJ     *a    = (Mat_MPIAIJ *)mat->data;
3148:   Mat             B    = a->B;
3149:   Vec             lvec = a->lvec, lcmap;
3150:   PetscInt        i, cstart, cend, Bn = B->cmap->N;
3151:   MPI_Comm        comm;
3152:   VecScatter      Mvctx = a->Mvctx;

3154:   PetscFunctionBegin;
3155:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3156:   PetscCall(ISGetLocalSize(iscol, &ncols));

3158:   /* (1) iscol is a sub-column vector of mat, pad it with '-1.' to form a full vector x */
3159:   PetscCall(MatCreateVecs(mat, &x, NULL));
3160:   PetscCall(VecSet(x, -1.0));
3161:   PetscCall(VecDuplicate(x, &cmap));
3162:   PetscCall(VecSet(cmap, -1.0));

3164:   /* Get start indices */
3165:   PetscCallMPI(MPI_Scan(&ncols, &isstart, 1, MPIU_INT, MPI_SUM, comm));
3166:   isstart -= ncols;
3167:   PetscCall(MatGetOwnershipRangeColumn(mat, &cstart, &cend));

3169:   PetscCall(ISGetIndices(iscol, &is_idx));
3170:   PetscCall(VecGetArray(x, &xarray));
3171:   PetscCall(VecGetArray(cmap, &cmaparray));
3172:   PetscCall(PetscMalloc1(ncols, &idx));
3173:   for (i = 0; i < ncols; i++) {
3174:     xarray[is_idx[i] - cstart]    = (PetscScalar)is_idx[i];
3175:     cmaparray[is_idx[i] - cstart] = i + isstart;        /* global index of iscol[i] */
3176:     idx[i]                        = is_idx[i] - cstart; /* local index of iscol[i]  */
3177:   }
3178:   PetscCall(VecRestoreArray(x, &xarray));
3179:   PetscCall(VecRestoreArray(cmap, &cmaparray));
3180:   PetscCall(ISRestoreIndices(iscol, &is_idx));

3182:   /* Get iscol_d */
3183:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, iscol_d));
3184:   PetscCall(ISGetBlockSize(iscol, &i));
3185:   PetscCall(ISSetBlockSize(*iscol_d, i));

3187:   /* Get isrow_d */
3188:   PetscCall(ISGetLocalSize(isrow, &m));
3189:   rstart = mat->rmap->rstart;
3190:   PetscCall(PetscMalloc1(m, &idx));
3191:   PetscCall(ISGetIndices(isrow, &is_idx));
3192:   for (i = 0; i < m; i++) idx[i] = is_idx[i] - rstart;
3193:   PetscCall(ISRestoreIndices(isrow, &is_idx));

3195:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, m, idx, PETSC_OWN_POINTER, isrow_d));
3196:   PetscCall(ISGetBlockSize(isrow, &i));
3197:   PetscCall(ISSetBlockSize(*isrow_d, i));

3199:   /* (2) Scatter x and cmap using aij->Mvctx to get their off-process portions (see MatMult_MPIAIJ) */
3200:   PetscCall(VecScatterBegin(Mvctx, x, lvec, INSERT_VALUES, SCATTER_FORWARD));
3201:   PetscCall(VecScatterEnd(Mvctx, x, lvec, INSERT_VALUES, SCATTER_FORWARD));

3203:   PetscCall(VecDuplicate(lvec, &lcmap));

3205:   PetscCall(VecScatterBegin(Mvctx, cmap, lcmap, INSERT_VALUES, SCATTER_FORWARD));
3206:   PetscCall(VecScatterEnd(Mvctx, cmap, lcmap, INSERT_VALUES, SCATTER_FORWARD));

3208:   /* (3) create sequential iscol_o (a subset of iscol) and isgarray */
3209:   /* off-process column indices */
3210:   count = 0;
3211:   PetscCall(PetscMalloc1(Bn, &idx));
3212:   PetscCall(PetscMalloc1(Bn, &cmap1));

3214:   PetscCall(VecGetArray(lvec, &xarray));
3215:   PetscCall(VecGetArray(lcmap, &cmaparray));
3216:   for (i = 0; i < Bn; i++) {
3217:     if (PetscRealPart(xarray[i]) > -1.0) {
3218:       idx[count]   = i;                                     /* local column index in off-diagonal part B */
3219:       cmap1[count] = (PetscInt)PetscRealPart(cmaparray[i]); /* column index in submat */
3220:       count++;
3221:     }
3222:   }
3223:   PetscCall(VecRestoreArray(lvec, &xarray));
3224:   PetscCall(VecRestoreArray(lcmap, &cmaparray));

3226:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count, idx, PETSC_COPY_VALUES, iscol_o));
3227:   /* cannot ensure iscol_o has same blocksize as iscol! */

3229:   PetscCall(PetscFree(idx));
3230:   *garray = cmap1;

3232:   PetscCall(VecDestroy(&x));
3233:   PetscCall(VecDestroy(&cmap));
3234:   PetscCall(VecDestroy(&lcmap));
3235:   PetscFunctionReturn(PETSC_SUCCESS);
3236: }

3238: /* isrow and iscol have same processor distribution as mat, output *submat is a submatrix of local mat */
3239: PetscErrorCode MatCreateSubMatrix_MPIAIJ_SameRowColDist(Mat mat, IS isrow, IS iscol, MatReuse call, Mat *submat)
3240: {
3241:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)mat->data, *asub;
3242:   Mat         M = NULL;
3243:   MPI_Comm    comm;
3244:   IS          iscol_d, isrow_d, iscol_o;
3245:   Mat         Asub = NULL, Bsub = NULL;
3246:   PetscInt    n;

3248:   PetscFunctionBegin;
3249:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));

3251:   if (call == MAT_REUSE_MATRIX) {
3252:     /* Retrieve isrow_d, iscol_d and iscol_o from submat */
3253:     PetscCall(PetscObjectQuery((PetscObject)*submat, "isrow_d", (PetscObject *)&isrow_d));
3254:     PetscCheck(isrow_d, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "isrow_d passed in was not used before, cannot reuse");

3256:     PetscCall(PetscObjectQuery((PetscObject)*submat, "iscol_d", (PetscObject *)&iscol_d));
3257:     PetscCheck(iscol_d, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "iscol_d passed in was not used before, cannot reuse");

3259:     PetscCall(PetscObjectQuery((PetscObject)*submat, "iscol_o", (PetscObject *)&iscol_o));
3260:     PetscCheck(iscol_o, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "iscol_o passed in was not used before, cannot reuse");

3262:     /* Update diagonal and off-diagonal portions of submat */
3263:     asub = (Mat_MPIAIJ *)(*submat)->data;
3264:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->A, isrow_d, iscol_d, PETSC_DECIDE, MAT_REUSE_MATRIX, &asub->A));
3265:     PetscCall(ISGetLocalSize(iscol_o, &n));
3266:     if (n) PetscCall(MatCreateSubMatrix_SeqAIJ(a->B, isrow_d, iscol_o, PETSC_DECIDE, MAT_REUSE_MATRIX, &asub->B));
3267:     PetscCall(MatAssemblyBegin(*submat, MAT_FINAL_ASSEMBLY));
3268:     PetscCall(MatAssemblyEnd(*submat, MAT_FINAL_ASSEMBLY));

3270:   } else { /* call == MAT_INITIAL_MATRIX) */
3271:     const PetscInt *garray;
3272:     PetscInt        BsubN;

3274:     /* Create isrow_d, iscol_d, iscol_o and isgarray (replace isgarray with array?) */
3275:     PetscCall(ISGetSeqIS_SameColDist_Private(mat, isrow, iscol, &isrow_d, &iscol_d, &iscol_o, &garray));

3277:     /* Create local submatrices Asub and Bsub */
3278:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->A, isrow_d, iscol_d, PETSC_DECIDE, MAT_INITIAL_MATRIX, &Asub));
3279:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->B, isrow_d, iscol_o, PETSC_DECIDE, MAT_INITIAL_MATRIX, &Bsub));

3281:     /* Create submatrix M */
3282:     PetscCall(MatCreateMPIAIJWithSeqAIJ(comm, Asub, Bsub, garray, &M));

3284:     /* If Bsub has empty columns, compress iscol_o such that it will retrieve condensed Bsub from a->B during reuse */
3285:     asub = (Mat_MPIAIJ *)M->data;

3287:     PetscCall(ISGetLocalSize(iscol_o, &BsubN));
3288:     n = asub->B->cmap->N;
3289:     if (BsubN > n) {
3290:       /* This case can be tested using ~petsc/src/tao/bound/tutorials/runplate2_3 */
3291:       const PetscInt *idx;
3292:       PetscInt        i, j, *idx_new, *subgarray = asub->garray;
3293:       PetscCall(PetscInfo(M, "submatrix Bn %" PetscInt_FMT " != BsubN %" PetscInt_FMT ", update iscol_o\n", n, BsubN));

3295:       PetscCall(PetscMalloc1(n, &idx_new));
3296:       j = 0;
3297:       PetscCall(ISGetIndices(iscol_o, &idx));
3298:       for (i = 0; i < n; i++) {
3299:         if (j >= BsubN) break;
3300:         while (subgarray[i] > garray[j]) j++;

3302:         if (subgarray[i] == garray[j]) {
3303:           idx_new[i] = idx[j++];
3304:         } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "subgarray[%" PetscInt_FMT "]=%" PetscInt_FMT " cannot < garray[%" PetscInt_FMT "]=%" PetscInt_FMT, i, subgarray[i], j, garray[j]);
3305:       }
3306:       PetscCall(ISRestoreIndices(iscol_o, &idx));

3308:       PetscCall(ISDestroy(&iscol_o));
3309:       PetscCall(ISCreateGeneral(PETSC_COMM_SELF, n, idx_new, PETSC_OWN_POINTER, &iscol_o));

3311:     } else if (BsubN < n) {
3312:       SETERRQ(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);
3313:     }

3315:     PetscCall(PetscFree(garray));
3316:     *submat = M;

3318:     /* Save isrow_d, iscol_d and iscol_o used in processor for next request */
3319:     PetscCall(PetscObjectCompose((PetscObject)M, "isrow_d", (PetscObject)isrow_d));
3320:     PetscCall(ISDestroy(&isrow_d));

3322:     PetscCall(PetscObjectCompose((PetscObject)M, "iscol_d", (PetscObject)iscol_d));
3323:     PetscCall(ISDestroy(&iscol_d));

3325:     PetscCall(PetscObjectCompose((PetscObject)M, "iscol_o", (PetscObject)iscol_o));
3326:     PetscCall(ISDestroy(&iscol_o));
3327:   }
3328:   PetscFunctionReturn(PETSC_SUCCESS);
3329: }

3331: PetscErrorCode MatCreateSubMatrix_MPIAIJ(Mat mat, IS isrow, IS iscol, MatReuse call, Mat *newmat)
3332: {
3333:   IS        iscol_local = NULL, isrow_d;
3334:   PetscInt  csize;
3335:   PetscInt  n, i, j, start, end;
3336:   PetscBool sameRowDist = PETSC_FALSE, sameDist[2], tsameDist[2];
3337:   MPI_Comm  comm;

3339:   PetscFunctionBegin;
3340:   /* If isrow has same processor distribution as mat,
3341:      call MatCreateSubMatrix_MPIAIJ_SameRowDist() to avoid using a hash table with global size of iscol */
3342:   if (call == MAT_REUSE_MATRIX) {
3343:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "isrow_d", (PetscObject *)&isrow_d));
3344:     if (isrow_d) {
3345:       sameRowDist  = PETSC_TRUE;
3346:       tsameDist[1] = PETSC_TRUE; /* sameColDist */
3347:     } else {
3348:       PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_local));
3349:       if (iscol_local) {
3350:         sameRowDist  = PETSC_TRUE;
3351:         tsameDist[1] = PETSC_FALSE; /* !sameColDist */
3352:       }
3353:     }
3354:   } else {
3355:     /* Check if isrow has same processor distribution as mat */
3356:     sameDist[0] = PETSC_FALSE;
3357:     PetscCall(ISGetLocalSize(isrow, &n));
3358:     if (!n) {
3359:       sameDist[0] = PETSC_TRUE;
3360:     } else {
3361:       PetscCall(ISGetMinMax(isrow, &i, &j));
3362:       PetscCall(MatGetOwnershipRange(mat, &start, &end));
3363:       if (i >= start && j < end) sameDist[0] = PETSC_TRUE;
3364:     }

3366:     /* Check if iscol has same processor distribution as mat */
3367:     sameDist[1] = PETSC_FALSE;
3368:     PetscCall(ISGetLocalSize(iscol, &n));
3369:     if (!n) {
3370:       sameDist[1] = PETSC_TRUE;
3371:     } else {
3372:       PetscCall(ISGetMinMax(iscol, &i, &j));
3373:       PetscCall(MatGetOwnershipRangeColumn(mat, &start, &end));
3374:       if (i >= start && j < end) sameDist[1] = PETSC_TRUE;
3375:     }

3377:     PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3378:     PetscCall(MPIU_Allreduce(&sameDist, &tsameDist, 2, MPIU_BOOL, MPI_LAND, comm));
3379:     sameRowDist = tsameDist[0];
3380:   }

3382:   if (sameRowDist) {
3383:     if (tsameDist[1]) { /* sameRowDist & sameColDist */
3384:       /* isrow and iscol have same processor distribution as mat */
3385:       PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowColDist(mat, isrow, iscol, call, newmat));
3386:       PetscFunctionReturn(PETSC_SUCCESS);
3387:     } else { /* sameRowDist */
3388:       /* isrow has same processor distribution as mat */
3389:       if (call == MAT_INITIAL_MATRIX) {
3390:         PetscBool sorted;
3391:         PetscCall(ISGetSeqIS_Private(mat, iscol, &iscol_local));
3392:         PetscCall(ISGetLocalSize(iscol_local, &n)); /* local size of iscol_local = global columns of newmat */
3393:         PetscCall(ISGetSize(iscol, &i));
3394:         PetscCheck(n == i, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "n %" PetscInt_FMT " != size of iscol %" PetscInt_FMT, n, i);

3396:         PetscCall(ISSorted(iscol_local, &sorted));
3397:         if (sorted) {
3398:           /* MatCreateSubMatrix_MPIAIJ_SameRowDist() requires iscol_local be sorted; it can have duplicate indices */
3399:           PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowDist(mat, isrow, iscol, iscol_local, MAT_INITIAL_MATRIX, newmat));
3400:           PetscFunctionReturn(PETSC_SUCCESS);
3401:         }
3402:       } else { /* call == MAT_REUSE_MATRIX */
3403:         IS iscol_sub;
3404:         PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_sub));
3405:         if (iscol_sub) {
3406:           PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowDist(mat, isrow, iscol, NULL, call, newmat));
3407:           PetscFunctionReturn(PETSC_SUCCESS);
3408:         }
3409:       }
3410:     }
3411:   }

3413:   /* General case: iscol -> iscol_local which has global size of iscol */
3414:   if (call == MAT_REUSE_MATRIX) {
3415:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "ISAllGather", (PetscObject *)&iscol_local));
3416:     PetscCheck(iscol_local, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");
3417:   } else {
3418:     if (!iscol_local) PetscCall(ISGetSeqIS_Private(mat, iscol, &iscol_local));
3419:   }

3421:   PetscCall(ISGetLocalSize(iscol, &csize));
3422:   PetscCall(MatCreateSubMatrix_MPIAIJ_nonscalable(mat, isrow, iscol_local, csize, call, newmat));

3424:   if (call == MAT_INITIAL_MATRIX) {
3425:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "ISAllGather", (PetscObject)iscol_local));
3426:     PetscCall(ISDestroy(&iscol_local));
3427:   }
3428:   PetscFunctionReturn(PETSC_SUCCESS);
3429: }

3431: /*@C
3432:   MatCreateMPIAIJWithSeqAIJ - creates a `MATMPIAIJ` matrix using `MATSEQAIJ` matrices that contain the "diagonal"
3433:   and "off-diagonal" part of the matrix in CSR format.

3435:   Collective

3437:   Input Parameters:
3438: + comm   - MPI communicator
3439: . A      - "diagonal" portion of matrix
3440: . B      - "off-diagonal" portion of matrix, may have empty columns, will be destroyed by this routine
3441: - garray - global index of `B` columns

3443:   Output Parameter:
3444: . mat - the matrix, with input `A` as its local diagonal matrix

3446:   Level: advanced

3448:   Notes:
3449:   See `MatCreateAIJ()` for the definition of "diagonal" and "off-diagonal" portion of the matrix.

3451:   `A` becomes part of output mat, `B` is destroyed by this routine. The user cannot use `A` and `B` anymore.

3453: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateMPIAIJWithSplitArrays()`
3454: @*/
3455: PetscErrorCode MatCreateMPIAIJWithSeqAIJ(MPI_Comm comm, Mat A, Mat B, const PetscInt garray[], Mat *mat)
3456: {
3457:   Mat_MPIAIJ        *maij;
3458:   Mat_SeqAIJ        *b  = (Mat_SeqAIJ *)B->data, *bnew;
3459:   PetscInt          *oi = b->i, *oj = b->j, i, nz, col;
3460:   const PetscScalar *oa;
3461:   Mat                Bnew;
3462:   PetscInt           m, n, N;
3463:   MatType            mpi_mat_type;

3465:   PetscFunctionBegin;
3466:   PetscCall(MatCreate(comm, mat));
3467:   PetscCall(MatGetSize(A, &m, &n));
3468:   PetscCheck(m == B->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Am %" PetscInt_FMT " != Bm %" PetscInt_FMT, m, B->rmap->N);
3469:   PetscCheck(PetscAbs(A->rmap->bs) == PetscAbs(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);
3470:   /* remove check below; When B is created using iscol_o from ISGetSeqIS_SameColDist_Private(), its bs may not be same as A */
3471:   /* PetscCheck(A->cmap->bs == B->cmap->bs,PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"A column bs %" PetscInt_FMT " != B column bs %" PetscInt_FMT,A->cmap->bs,B->cmap->bs); */

3473:   /* Get global columns of mat */
3474:   PetscCall(MPIU_Allreduce(&n, &N, 1, MPIU_INT, MPI_SUM, comm));

3476:   PetscCall(MatSetSizes(*mat, m, n, PETSC_DECIDE, N));
3477:   /* Determine the type of MPI matrix that should be created from the type of matrix A, which holds the "diagonal" portion. */
3478:   PetscCall(MatGetMPIMatType_Private(A, &mpi_mat_type));
3479:   PetscCall(MatSetType(*mat, mpi_mat_type));

3481:   if (A->rmap->bs > 1 || A->cmap->bs > 1) PetscCall(MatSetBlockSizes(*mat, A->rmap->bs, A->cmap->bs));
3482:   maij = (Mat_MPIAIJ *)(*mat)->data;

3484:   (*mat)->preallocated = PETSC_TRUE;

3486:   PetscCall(PetscLayoutSetUp((*mat)->rmap));
3487:   PetscCall(PetscLayoutSetUp((*mat)->cmap));

3489:   /* Set A as diagonal portion of *mat */
3490:   maij->A = A;

3492:   nz = oi[m];
3493:   for (i = 0; i < nz; i++) {
3494:     col   = oj[i];
3495:     oj[i] = garray[col];
3496:   }

3498:   /* Set Bnew as off-diagonal portion of *mat */
3499:   PetscCall(MatSeqAIJGetArrayRead(B, &oa));
3500:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, N, oi, oj, (PetscScalar *)oa, &Bnew));
3501:   PetscCall(MatSeqAIJRestoreArrayRead(B, &oa));
3502:   bnew        = (Mat_SeqAIJ *)Bnew->data;
3503:   bnew->maxnz = b->maxnz; /* allocated nonzeros of B */
3504:   maij->B     = Bnew;

3506:   PetscCheck(B->rmap->N == Bnew->rmap->N, PETSC_COMM_SELF, PETSC_ERR_PLIB, "BN %" PetscInt_FMT " != BnewN %" PetscInt_FMT, B->rmap->N, Bnew->rmap->N);

3508:   b->singlemalloc = PETSC_FALSE; /* B arrays are shared by Bnew */
3509:   b->free_a       = PETSC_FALSE;
3510:   b->free_ij      = PETSC_FALSE;
3511:   PetscCall(MatDestroy(&B));

3513:   bnew->singlemalloc = PETSC_TRUE; /* arrays will be freed by MatDestroy(&Bnew) */
3514:   bnew->free_a       = PETSC_TRUE;
3515:   bnew->free_ij      = PETSC_TRUE;

3517:   /* condense columns of maij->B */
3518:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
3519:   PetscCall(MatAssemblyBegin(*mat, MAT_FINAL_ASSEMBLY));
3520:   PetscCall(MatAssemblyEnd(*mat, MAT_FINAL_ASSEMBLY));
3521:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_FALSE));
3522:   PetscCall(MatSetOption(*mat, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
3523:   PetscFunctionReturn(PETSC_SUCCESS);
3524: }

3526: extern PetscErrorCode MatCreateSubMatrices_MPIAIJ_SingleIS_Local(Mat, PetscInt, const IS[], const IS[], MatReuse, PetscBool, Mat *);

3528: PetscErrorCode MatCreateSubMatrix_MPIAIJ_SameRowDist(Mat mat, IS isrow, IS iscol, IS iscol_local, MatReuse call, Mat *newmat)
3529: {
3530:   PetscInt        i, m, n, rstart, row, rend, nz, j, bs, cbs;
3531:   PetscInt       *ii, *jj, nlocal, *dlens, *olens, dlen, olen, jend, mglobal;
3532:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)mat->data;
3533:   Mat             M, Msub, B = a->B;
3534:   MatScalar      *aa;
3535:   Mat_SeqAIJ     *aij;
3536:   PetscInt       *garray = a->garray, *colsub, Ncols;
3537:   PetscInt        count, Bn = B->cmap->N, cstart = mat->cmap->rstart, cend = mat->cmap->rend;
3538:   IS              iscol_sub, iscmap;
3539:   const PetscInt *is_idx, *cmap;
3540:   PetscBool       allcolumns = PETSC_FALSE;
3541:   MPI_Comm        comm;

3543:   PetscFunctionBegin;
3544:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3545:   if (call == MAT_REUSE_MATRIX) {
3546:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_sub));
3547:     PetscCheck(iscol_sub, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "SubIScol passed in was not used before, cannot reuse");
3548:     PetscCall(ISGetLocalSize(iscol_sub, &count));

3550:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "Subcmap", (PetscObject *)&iscmap));
3551:     PetscCheck(iscmap, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Subcmap passed in was not used before, cannot reuse");

3553:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubMatrix", (PetscObject *)&Msub));
3554:     PetscCheck(Msub, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");

3556:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol_sub, MAT_REUSE_MATRIX, PETSC_FALSE, &Msub));

3558:   } else { /* call == MAT_INITIAL_MATRIX) */
3559:     PetscBool flg;

3561:     PetscCall(ISGetLocalSize(iscol, &n));
3562:     PetscCall(ISGetSize(iscol, &Ncols));

3564:     /* (1) iscol -> nonscalable iscol_local */
3565:     /* Check for special case: each processor gets entire matrix columns */
3566:     PetscCall(ISIdentity(iscol_local, &flg));
3567:     if (flg && n == mat->cmap->N) allcolumns = PETSC_TRUE;
3568:     PetscCall(MPIU_Allreduce(MPI_IN_PLACE, &allcolumns, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));
3569:     if (allcolumns) {
3570:       iscol_sub = iscol_local;
3571:       PetscCall(PetscObjectReference((PetscObject)iscol_local));
3572:       PetscCall(ISCreateStride(PETSC_COMM_SELF, n, 0, 1, &iscmap));

3574:     } else {
3575:       /* (2) iscol_local -> iscol_sub and iscmap. Implementation below requires iscol_local be sorted, it can have duplicate indices */
3576:       PetscInt *idx, *cmap1, k;
3577:       PetscCall(PetscMalloc1(Ncols, &idx));
3578:       PetscCall(PetscMalloc1(Ncols, &cmap1));
3579:       PetscCall(ISGetIndices(iscol_local, &is_idx));
3580:       count = 0;
3581:       k     = 0;
3582:       for (i = 0; i < Ncols; i++) {
3583:         j = is_idx[i];
3584:         if (j >= cstart && j < cend) {
3585:           /* diagonal part of mat */
3586:           idx[count]     = j;
3587:           cmap1[count++] = i; /* column index in submat */
3588:         } else if (Bn) {
3589:           /* off-diagonal part of mat */
3590:           if (j == garray[k]) {
3591:             idx[count]     = j;
3592:             cmap1[count++] = i; /* column index in submat */
3593:           } else if (j > garray[k]) {
3594:             while (j > garray[k] && k < Bn - 1) k++;
3595:             if (j == garray[k]) {
3596:               idx[count]     = j;
3597:               cmap1[count++] = i; /* column index in submat */
3598:             }
3599:           }
3600:         }
3601:       }
3602:       PetscCall(ISRestoreIndices(iscol_local, &is_idx));

3604:       PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count, idx, PETSC_OWN_POINTER, &iscol_sub));
3605:       PetscCall(ISGetBlockSize(iscol, &cbs));
3606:       PetscCall(ISSetBlockSize(iscol_sub, cbs));

3608:       PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)iscol_local), count, cmap1, PETSC_OWN_POINTER, &iscmap));
3609:     }

3611:     /* (3) Create sequential Msub */
3612:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol_sub, MAT_INITIAL_MATRIX, allcolumns, &Msub));
3613:   }

3615:   PetscCall(ISGetLocalSize(iscol_sub, &count));
3616:   aij = (Mat_SeqAIJ *)(Msub)->data;
3617:   ii  = aij->i;
3618:   PetscCall(ISGetIndices(iscmap, &cmap));

3620:   /*
3621:       m - number of local rows
3622:       Ncols - number of columns (same on all processors)
3623:       rstart - first row in new global matrix generated
3624:   */
3625:   PetscCall(MatGetSize(Msub, &m, NULL));

3627:   if (call == MAT_INITIAL_MATRIX) {
3628:     /* (4) Create parallel newmat */
3629:     PetscMPIInt rank, size;
3630:     PetscInt    csize;

3632:     PetscCallMPI(MPI_Comm_size(comm, &size));
3633:     PetscCallMPI(MPI_Comm_rank(comm, &rank));

3635:     /*
3636:         Determine the number of non-zeros in the diagonal and off-diagonal
3637:         portions of the matrix in order to do correct preallocation
3638:     */

3640:     /* first get start and end of "diagonal" columns */
3641:     PetscCall(ISGetLocalSize(iscol, &csize));
3642:     if (csize == PETSC_DECIDE) {
3643:       PetscCall(ISGetSize(isrow, &mglobal));
3644:       if (mglobal == Ncols) { /* square matrix */
3645:         nlocal = m;
3646:       } else {
3647:         nlocal = Ncols / size + ((Ncols % size) > rank);
3648:       }
3649:     } else {
3650:       nlocal = csize;
3651:     }
3652:     PetscCallMPI(MPI_Scan(&nlocal, &rend, 1, MPIU_INT, MPI_SUM, comm));
3653:     rstart = rend - nlocal;
3654:     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);

3656:     /* next, compute all the lengths */
3657:     jj = aij->j;
3658:     PetscCall(PetscMalloc1(2 * m + 1, &dlens));
3659:     olens = dlens + m;
3660:     for (i = 0; i < m; i++) {
3661:       jend = ii[i + 1] - ii[i];
3662:       olen = 0;
3663:       dlen = 0;
3664:       for (j = 0; j < jend; j++) {
3665:         if (cmap[*jj] < rstart || cmap[*jj] >= rend) olen++;
3666:         else dlen++;
3667:         jj++;
3668:       }
3669:       olens[i] = olen;
3670:       dlens[i] = dlen;
3671:     }

3673:     PetscCall(ISGetBlockSize(isrow, &bs));
3674:     PetscCall(ISGetBlockSize(iscol, &cbs));

3676:     PetscCall(MatCreate(comm, &M));
3677:     PetscCall(MatSetSizes(M, m, nlocal, PETSC_DECIDE, Ncols));
3678:     PetscCall(MatSetBlockSizes(M, bs, cbs));
3679:     PetscCall(MatSetType(M, ((PetscObject)mat)->type_name));
3680:     PetscCall(MatMPIAIJSetPreallocation(M, 0, dlens, 0, olens));
3681:     PetscCall(PetscFree(dlens));

3683:   } else { /* call == MAT_REUSE_MATRIX */
3684:     M = *newmat;
3685:     PetscCall(MatGetLocalSize(M, &i, NULL));
3686:     PetscCheck(i == m, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Previous matrix must be same size/layout as request");
3687:     PetscCall(MatZeroEntries(M));
3688:     /*
3689:          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3690:        rather than the slower MatSetValues().
3691:     */
3692:     M->was_assembled = PETSC_TRUE;
3693:     M->assembled     = PETSC_FALSE;
3694:   }

3696:   /* (5) Set values of Msub to *newmat */
3697:   PetscCall(PetscMalloc1(count, &colsub));
3698:   PetscCall(MatGetOwnershipRange(M, &rstart, NULL));

3700:   jj = aij->j;
3701:   PetscCall(MatSeqAIJGetArrayRead(Msub, (const PetscScalar **)&aa));
3702:   for (i = 0; i < m; i++) {
3703:     row = rstart + i;
3704:     nz  = ii[i + 1] - ii[i];
3705:     for (j = 0; j < nz; j++) colsub[j] = cmap[jj[j]];
3706:     PetscCall(MatSetValues_MPIAIJ(M, 1, &row, nz, colsub, aa, INSERT_VALUES));
3707:     jj += nz;
3708:     aa += nz;
3709:   }
3710:   PetscCall(MatSeqAIJRestoreArrayRead(Msub, (const PetscScalar **)&aa));
3711:   PetscCall(ISRestoreIndices(iscmap, &cmap));

3713:   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
3714:   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));

3716:   PetscCall(PetscFree(colsub));

3718:   /* save Msub, iscol_sub and iscmap used in processor for next request */
3719:   if (call == MAT_INITIAL_MATRIX) {
3720:     *newmat = M;
3721:     PetscCall(PetscObjectCompose((PetscObject)(*newmat), "SubMatrix", (PetscObject)Msub));
3722:     PetscCall(MatDestroy(&Msub));

3724:     PetscCall(PetscObjectCompose((PetscObject)(*newmat), "SubIScol", (PetscObject)iscol_sub));
3725:     PetscCall(ISDestroy(&iscol_sub));

3727:     PetscCall(PetscObjectCompose((PetscObject)(*newmat), "Subcmap", (PetscObject)iscmap));
3728:     PetscCall(ISDestroy(&iscmap));

3730:     if (iscol_local) {
3731:       PetscCall(PetscObjectCompose((PetscObject)(*newmat), "ISAllGather", (PetscObject)iscol_local));
3732:       PetscCall(ISDestroy(&iscol_local));
3733:     }
3734:   }
3735:   PetscFunctionReturn(PETSC_SUCCESS);
3736: }

3738: /*
3739:     Not great since it makes two copies of the submatrix, first an SeqAIJ
3740:   in local and then by concatenating the local matrices the end result.
3741:   Writing it directly would be much like MatCreateSubMatrices_MPIAIJ()

3743:   This requires a sequential iscol with all indices.
3744: */
3745: PetscErrorCode MatCreateSubMatrix_MPIAIJ_nonscalable(Mat mat, IS isrow, IS iscol, PetscInt csize, MatReuse call, Mat *newmat)
3746: {
3747:   PetscMPIInt rank, size;
3748:   PetscInt    i, m, n, rstart, row, rend, nz, *cwork, j, bs, cbs;
3749:   PetscInt   *ii, *jj, nlocal, *dlens, *olens, dlen, olen, jend, mglobal;
3750:   Mat         M, Mreuse;
3751:   MatScalar  *aa, *vwork;
3752:   MPI_Comm    comm;
3753:   Mat_SeqAIJ *aij;
3754:   PetscBool   colflag, allcolumns = PETSC_FALSE;

3756:   PetscFunctionBegin;
3757:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3758:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
3759:   PetscCallMPI(MPI_Comm_size(comm, &size));

3761:   /* Check for special case: each processor gets entire matrix columns */
3762:   PetscCall(ISIdentity(iscol, &colflag));
3763:   PetscCall(ISGetLocalSize(iscol, &n));
3764:   if (colflag && n == mat->cmap->N) allcolumns = PETSC_TRUE;
3765:   PetscCall(MPIU_Allreduce(MPI_IN_PLACE, &allcolumns, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));

3767:   if (call == MAT_REUSE_MATRIX) {
3768:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubMatrix", (PetscObject *)&Mreuse));
3769:     PetscCheck(Mreuse, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");
3770:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol, MAT_REUSE_MATRIX, allcolumns, &Mreuse));
3771:   } else {
3772:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol, MAT_INITIAL_MATRIX, allcolumns, &Mreuse));
3773:   }

3775:   /*
3776:       m - number of local rows
3777:       n - number of columns (same on all processors)
3778:       rstart - first row in new global matrix generated
3779:   */
3780:   PetscCall(MatGetSize(Mreuse, &m, &n));
3781:   PetscCall(MatGetBlockSizes(Mreuse, &bs, &cbs));
3782:   if (call == MAT_INITIAL_MATRIX) {
3783:     aij = (Mat_SeqAIJ *)(Mreuse)->data;
3784:     ii  = aij->i;
3785:     jj  = aij->j;

3787:     /*
3788:         Determine the number of non-zeros in the diagonal and off-diagonal
3789:         portions of the matrix in order to do correct preallocation
3790:     */

3792:     /* first get start and end of "diagonal" columns */
3793:     if (csize == PETSC_DECIDE) {
3794:       PetscCall(ISGetSize(isrow, &mglobal));
3795:       if (mglobal == n) { /* square matrix */
3796:         nlocal = m;
3797:       } else {
3798:         nlocal = n / size + ((n % size) > rank);
3799:       }
3800:     } else {
3801:       nlocal = csize;
3802:     }
3803:     PetscCallMPI(MPI_Scan(&nlocal, &rend, 1, MPIU_INT, MPI_SUM, comm));
3804:     rstart = rend - nlocal;
3805:     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);

3807:     /* next, compute all the lengths */
3808:     PetscCall(PetscMalloc1(2 * m + 1, &dlens));
3809:     olens = dlens + m;
3810:     for (i = 0; i < m; i++) {
3811:       jend = ii[i + 1] - ii[i];
3812:       olen = 0;
3813:       dlen = 0;
3814:       for (j = 0; j < jend; j++) {
3815:         if (*jj < rstart || *jj >= rend) olen++;
3816:         else dlen++;
3817:         jj++;
3818:       }
3819:       olens[i] = olen;
3820:       dlens[i] = dlen;
3821:     }
3822:     PetscCall(MatCreate(comm, &M));
3823:     PetscCall(MatSetSizes(M, m, nlocal, PETSC_DECIDE, n));
3824:     PetscCall(MatSetBlockSizes(M, bs, cbs));
3825:     PetscCall(MatSetType(M, ((PetscObject)mat)->type_name));
3826:     PetscCall(MatMPIAIJSetPreallocation(M, 0, dlens, 0, olens));
3827:     PetscCall(PetscFree(dlens));
3828:   } else {
3829:     PetscInt ml, nl;

3831:     M = *newmat;
3832:     PetscCall(MatGetLocalSize(M, &ml, &nl));
3833:     PetscCheck(ml == m, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Previous matrix must be same size/layout as request");
3834:     PetscCall(MatZeroEntries(M));
3835:     /*
3836:          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3837:        rather than the slower MatSetValues().
3838:     */
3839:     M->was_assembled = PETSC_TRUE;
3840:     M->assembled     = PETSC_FALSE;
3841:   }
3842:   PetscCall(MatGetOwnershipRange(M, &rstart, &rend));
3843:   aij = (Mat_SeqAIJ *)(Mreuse)->data;
3844:   ii  = aij->i;
3845:   jj  = aij->j;

3847:   /* trigger copy to CPU if needed */
3848:   PetscCall(MatSeqAIJGetArrayRead(Mreuse, (const PetscScalar **)&aa));
3849:   for (i = 0; i < m; i++) {
3850:     row   = rstart + i;
3851:     nz    = ii[i + 1] - ii[i];
3852:     cwork = jj;
3853:     jj += nz;
3854:     vwork = aa;
3855:     aa += nz;
3856:     PetscCall(MatSetValues_MPIAIJ(M, 1, &row, nz, cwork, vwork, INSERT_VALUES));
3857:   }
3858:   PetscCall(MatSeqAIJRestoreArrayRead(Mreuse, (const PetscScalar **)&aa));

3860:   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
3861:   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));
3862:   *newmat = M;

3864:   /* save submatrix used in processor for next request */
3865:   if (call == MAT_INITIAL_MATRIX) {
3866:     PetscCall(PetscObjectCompose((PetscObject)M, "SubMatrix", (PetscObject)Mreuse));
3867:     PetscCall(MatDestroy(&Mreuse));
3868:   }
3869:   PetscFunctionReturn(PETSC_SUCCESS);
3870: }

3872: static PetscErrorCode MatMPIAIJSetPreallocationCSR_MPIAIJ(Mat B, const PetscInt Ii[], const PetscInt J[], const PetscScalar v[])
3873: {
3874:   PetscInt        m, cstart, cend, j, nnz, i, d, *ld;
3875:   PetscInt       *d_nnz, *o_nnz, nnz_max = 0, rstart, ii;
3876:   const PetscInt *JJ;
3877:   PetscBool       nooffprocentries;
3878:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)B->data;

3880:   PetscFunctionBegin;
3881:   PetscCheck(Ii[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Ii[0] must be 0 it is %" PetscInt_FMT, Ii[0]);

3883:   PetscCall(PetscLayoutSetUp(B->rmap));
3884:   PetscCall(PetscLayoutSetUp(B->cmap));
3885:   m      = B->rmap->n;
3886:   cstart = B->cmap->rstart;
3887:   cend   = B->cmap->rend;
3888:   rstart = B->rmap->rstart;

3890:   PetscCall(PetscCalloc2(m, &d_nnz, m, &o_nnz));

3892:   if (PetscDefined(USE_DEBUG)) {
3893:     for (i = 0; i < m; i++) {
3894:       nnz = Ii[i + 1] - Ii[i];
3895:       JJ  = J ? J + Ii[i] : NULL;
3896:       PetscCheck(nnz >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Local row %" PetscInt_FMT " has a negative %" PetscInt_FMT " number of columns", i, nnz);
3897:       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]);
3898:       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);
3899:     }
3900:   }

3902:   for (i = 0; i < m; i++) {
3903:     nnz     = Ii[i + 1] - Ii[i];
3904:     JJ      = J ? J + Ii[i] : NULL;
3905:     nnz_max = PetscMax(nnz_max, nnz);
3906:     d       = 0;
3907:     for (j = 0; j < nnz; j++) {
3908:       if (cstart <= JJ[j] && JJ[j] < cend) d++;
3909:     }
3910:     d_nnz[i] = d;
3911:     o_nnz[i] = nnz - d;
3912:   }
3913:   PetscCall(MatMPIAIJSetPreallocation(B, 0, d_nnz, 0, o_nnz));
3914:   PetscCall(PetscFree2(d_nnz, o_nnz));

3916:   for (i = 0; i < m; i++) {
3917:     ii = i + rstart;
3918:     PetscCall(MatSetValues_MPIAIJ(B, 1, &ii, Ii[i + 1] - Ii[i], J ? J + Ii[i] : NULL, v ? v + Ii[i] : NULL, INSERT_VALUES));
3919:   }
3920:   nooffprocentries    = B->nooffprocentries;
3921:   B->nooffprocentries = PETSC_TRUE;
3922:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
3923:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
3924:   B->nooffprocentries = nooffprocentries;

3926:   /* count number of entries below block diagonal */
3927:   PetscCall(PetscFree(Aij->ld));
3928:   PetscCall(PetscCalloc1(m, &ld));
3929:   Aij->ld = ld;
3930:   for (i = 0; i < m; i++) {
3931:     nnz = Ii[i + 1] - Ii[i];
3932:     j   = 0;
3933:     while (j < nnz && J[j] < cstart) j++;
3934:     ld[i] = j;
3935:     if (J) J += nnz;
3936:   }

3938:   PetscCall(MatSetOption(B, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
3939:   PetscFunctionReturn(PETSC_SUCCESS);
3940: }

3942: /*@
3943:   MatMPIAIJSetPreallocationCSR - Allocates memory for a sparse parallel matrix in `MATAIJ` format
3944:   (the default parallel PETSc format).

3946:   Collective

3948:   Input Parameters:
3949: + B - the matrix
3950: . i - the indices into j for the start of each local row (starts with zero)
3951: . j - the column indices for each local row (starts with zero)
3952: - v - optional values in the matrix

3954:   Level: developer

3956:   Notes:
3957:   The `i`, `j`, and `v` arrays ARE copied by this routine into the internal format used by PETSc;
3958:   thus you CANNOT change the matrix entries by changing the values of `v` after you have
3959:   called this routine. Use `MatCreateMPIAIJWithSplitArrays()` to avoid needing to copy the arrays.

3961:   The `i` and `j` indices are 0 based, and `i` indices are indices corresponding to the local `j` array.

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

3967: .vb
3968:         1 0 0
3969:         2 0 3     P0
3970:        -------
3971:         4 5 6     P1

3973:      Process0 [P0] rows_owned=[0,1]
3974:         i =  {0,1,3}  [size = nrow+1  = 2+1]
3975:         j =  {0,0,2}  [size = 3]
3976:         v =  {1,2,3}  [size = 3]

3978:      Process1 [P1] rows_owned=[2]
3979:         i =  {0,3}    [size = nrow+1  = 1+1]
3980:         j =  {0,1,2}  [size = 3]
3981:         v =  {4,5,6}  [size = 3]
3982: .ve

3984: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatCreateAIJ()`,
3985:           `MatCreateSeqAIJWithArrays()`, `MatCreateMPIAIJWithSplitArrays()`
3986: @*/
3987: PetscErrorCode MatMPIAIJSetPreallocationCSR(Mat B, const PetscInt i[], const PetscInt j[], const PetscScalar v[])
3988: {
3989:   PetscFunctionBegin;
3990:   PetscTryMethod(B, "MatMPIAIJSetPreallocationCSR_C", (Mat, const PetscInt[], const PetscInt[], const PetscScalar[]), (B, i, j, v));
3991:   PetscFunctionReturn(PETSC_SUCCESS);
3992: }

3994: /*@C
3995:   MatMPIAIJSetPreallocation - Preallocates memory for a sparse parallel matrix in `MATMPIAIJ` format
3996:   (the default parallel PETSc format).  For good matrix assembly performance
3997:   the user should preallocate the matrix storage by setting the parameters
3998:   `d_nz` (or `d_nnz`) and `o_nz` (or `o_nnz`).

4000:   Collective

4002:   Input Parameters:
4003: + B     - the matrix
4004: . d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4005:            (same value is used for all local rows)
4006: . d_nnz - array containing the number of nonzeros in the various rows of the
4007:            DIAGONAL portion of the local submatrix (possibly different for each row)
4008:            or `NULL` (`PETSC_NULL_INTEGER` in Fortran), if `d_nz` is used to specify the nonzero structure.
4009:            The size of this array is equal to the number of local rows, i.e 'm'.
4010:            For matrices that will be factored, you must leave room for (and set)
4011:            the diagonal entry even if it is zero.
4012: . o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4013:            submatrix (same value is used for all local rows).
4014: - o_nnz - array containing the number of nonzeros in the various rows of the
4015:            OFF-DIAGONAL portion of the local submatrix (possibly different for
4016:            each row) or `NULL` (`PETSC_NULL_INTEGER` in Fortran), if `o_nz` is used to specify the nonzero
4017:            structure. The size of this array is equal to the number
4018:            of local rows, i.e 'm'.

4020:   Example Usage:
4021:   Consider the following 8x8 matrix with 34 non-zero values, that is
4022:   assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4023:   proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4024:   as follows

4026: .vb
4027:             1  2  0  |  0  3  0  |  0  4
4028:     Proc0   0  5  6  |  7  0  0  |  8  0
4029:             9  0 10  | 11  0  0  | 12  0
4030:     -------------------------------------
4031:            13  0 14  | 15 16 17  |  0  0
4032:     Proc1   0 18  0  | 19 20 21  |  0  0
4033:             0  0  0  | 22 23  0  | 24  0
4034:     -------------------------------------
4035:     Proc2  25 26 27  |  0  0 28  | 29  0
4036:            30  0  0  | 31 32 33  |  0 34
4037: .ve

4039:   This can be represented as a collection of submatrices as
4040: .vb
4041:       A B C
4042:       D E F
4043:       G H I
4044: .ve

4046:   Where the submatrices A,B,C are owned by proc0, D,E,F are
4047:   owned by proc1, G,H,I are owned by proc2.

4049:   The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4050:   The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4051:   The 'M','N' parameters are 8,8, and have the same values on all procs.

4053:   The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4054:   submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4055:   corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4056:   Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4057:   part as `MATSEQAIJ` matrices. For example, proc1 will store [E] as a `MATSEQAIJ`
4058:   matrix, ans [DF] as another `MATSEQAIJ` matrix.

4060:   When `d_nz`, `o_nz` parameters are specified, `d_nz` storage elements are
4061:   allocated for every row of the local diagonal submatrix, and `o_nz`
4062:   storage locations are allocated for every row of the OFF-DIAGONAL submat.
4063:   One way to choose `d_nz` and `o_nz` is to use the max nonzerors per local
4064:   rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4065:   In this case, the values of `d_nz`, `o_nz` are
4066: .vb
4067:      proc0  dnz = 2, o_nz = 2
4068:      proc1  dnz = 3, o_nz = 2
4069:      proc2  dnz = 1, o_nz = 4
4070: .ve
4071:   We are allocating `m`*(`d_nz`+`o_nz`) storage locations for every proc. This
4072:   translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4073:   for proc3. i.e we are using 12+15+10=37 storage locations to store
4074:   34 values.

4076:   When `d_nnz`, `o_nnz` parameters are specified, the storage is specified
4077:   for every row, corresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4078:   In the above case the values for `d_nnz`, `o_nnz` are
4079: .vb
4080:      proc0 d_nnz = [2,2,2] and o_nnz = [2,2,2]
4081:      proc1 d_nnz = [3,3,2] and o_nnz = [2,1,1]
4082:      proc2 d_nnz = [1,1]   and o_nnz = [4,4]
4083: .ve
4084:   Here the space allocated is sum of all the above values i.e 34, and
4085:   hence pre-allocation is perfect.

4087:   Level: intermediate

4089:   Notes:
4090:   If the *_nnz parameter is given then the *_nz parameter is ignored

4092:   The `MATAIJ` format, also called compressed row storage (CSR), is compatible with standard Fortran
4093:   storage.  The stored row and column indices begin with zero.
4094:   See [Sparse Matrices](sec_matsparse) for details.

4096:   The parallel matrix is partitioned such that the first m0 rows belong to
4097:   process 0, the next m1 rows belong to process 1, the next m2 rows belong
4098:   to process 2 etc.. where m0,m1,m2... are the input parameter 'm'.

4100:   The DIAGONAL portion of the local submatrix of a processor can be defined
4101:   as the submatrix which is obtained by extraction the part corresponding to
4102:   the rows r1-r2 and columns c1-c2 of the global matrix, where r1 is the
4103:   first row that belongs to the processor, r2 is the last row belonging to
4104:   the this processor, and c1-c2 is range of indices of the local part of a
4105:   vector suitable for applying the matrix to.  This is an mxn matrix.  In the
4106:   common case of a square matrix, the row and column ranges are the same and
4107:   the DIAGONAL part is also square. The remaining portion of the local
4108:   submatrix (mxN) constitute the OFF-DIAGONAL portion.

4110:   If `o_nnz` and `d_nnz` are specified, then `o_nz` and `d_nz` are ignored.

4112:   You can call `MatGetInfo()` to get information on how effective the preallocation was;
4113:   for example the fields mallocs,nz_allocated,nz_used,nz_unneeded;
4114:   You can also run with the option `-info` and look for messages with the string
4115:   malloc in them to see if additional memory allocation was needed.

4117: .seealso: [](ch_matrices), `Mat`, [Sparse Matrices](sec_matsparse), `MATMPIAIJ`, `MATAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatCreateAIJ()`, `MatMPIAIJSetPreallocationCSR()`,
4118:           `MatGetInfo()`, `PetscSplitOwnership()`
4119: @*/
4120: PetscErrorCode MatMPIAIJSetPreallocation(Mat B, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[])
4121: {
4122:   PetscFunctionBegin;
4125:   PetscTryMethod(B, "MatMPIAIJSetPreallocation_C", (Mat, PetscInt, const PetscInt[], PetscInt, const PetscInt[]), (B, d_nz, d_nnz, o_nz, o_nnz));
4126:   PetscFunctionReturn(PETSC_SUCCESS);
4127: }

4129: /*@
4130:   MatCreateMPIAIJWithArrays - creates a `MATMPIAIJ` matrix using arrays that contain in standard
4131:   CSR format for the local rows.

4133:   Collective

4135:   Input Parameters:
4136: + comm - MPI communicator
4137: . m    - number of local rows (Cannot be `PETSC_DECIDE`)
4138: . n    - This value should be the same as the local size used in creating the
4139:        x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4140:        calculated if N is given) For square matrices n is almost always m.
4141: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4142: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4143: . i    - row indices; that is i[0] = 0, i[row] = i[row-1] + number of elements in that row of the matrix
4144: . j    - column indices
4145: - a    - optional matrix values

4147:   Output Parameter:
4148: . mat - the matrix

4150:   Level: intermediate

4152:   Notes:
4153:   The `i`, `j`, and `a` arrays ARE copied by this routine into the internal format used by PETSc;
4154:   thus you CANNOT change the matrix entries by changing the values of a[] after you have
4155:   called this routine. Use `MatCreateMPIAIJWithSplitArrays()` to avoid needing to copy the arrays.

4157:   The `i` and `j` indices are 0 based, and `i` indices are indices corresponding to the local `j` array.

4159:   The format which is used for the sparse matrix input, is equivalent to a
4160:   row-major ordering.. i.e for the following matrix, the input data expected is
4161:   as shown

4163:   Once you have created the matrix you can update it with new numerical values using MatUpdateMPIAIJWithArrays
4164: .vb
4165:         1 0 0
4166:         2 0 3     P0
4167:        -------
4168:         4 5 6     P1

4170:      Process0 [P0] rows_owned=[0,1]
4171:         i =  {0,1,3}  [size = nrow+1  = 2+1]
4172:         j =  {0,0,2}  [size = 3]
4173:         v =  {1,2,3}  [size = 3]

4175:      Process1 [P1] rows_owned=[2]
4176:         i =  {0,3}    [size = nrow+1  = 1+1]
4177:         j =  {0,1,2}  [size = 3]
4178:         v =  {4,5,6}  [size = 3]
4179: .ve

4181: .seealso: [](ch_matrices), `Mat`, `MATMPIAIK`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4182:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArrays()`
4183: @*/
4184: PetscErrorCode MatCreateMPIAIJWithArrays(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt M, PetscInt N, const PetscInt i[], const PetscInt j[], const PetscScalar a[], Mat *mat)
4185: {
4186:   PetscFunctionBegin;
4187:   PetscCheck(!i || !i[0], PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
4188:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
4189:   PetscCall(MatCreate(comm, mat));
4190:   PetscCall(MatSetSizes(*mat, m, n, M, N));
4191:   /* PetscCall(MatSetBlockSizes(M,bs,cbs)); */
4192:   PetscCall(MatSetType(*mat, MATMPIAIJ));
4193:   PetscCall(MatMPIAIJSetPreallocationCSR(*mat, i, j, a));
4194:   PetscFunctionReturn(PETSC_SUCCESS);
4195: }

4197: /*@
4198:   MatUpdateMPIAIJWithArrays - updates a `MATMPIAIJ` matrix using arrays that contain in standard
4199:   CSR format for the local rows. Only the numerical values are updated the other arrays must be identical to what was passed
4200:   from `MatCreateMPIAIJWithArrays()`

4202:   Deprecated: Use `MatUpdateMPIAIJWithArray()`

4204:   Collective

4206:   Input Parameters:
4207: + mat - the matrix
4208: . m   - number of local rows (Cannot be `PETSC_DECIDE`)
4209: . n   - This value should be the same as the local size used in creating the
4210:        x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4211:        calculated if N is given) For square matrices n is almost always m.
4212: . M   - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4213: . N   - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4214: . Ii  - row indices; that is Ii[0] = 0, Ii[row] = Ii[row-1] + number of elements in that row of the matrix
4215: . J   - column indices
4216: - v   - matrix values

4218:   Level: deprecated

4220: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4221:           `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArray()`
4222: @*/
4223: PetscErrorCode MatUpdateMPIAIJWithArrays(Mat mat, PetscInt m, PetscInt n, PetscInt M, PetscInt N, const PetscInt Ii[], const PetscInt J[], const PetscScalar v[])
4224: {
4225:   PetscInt        nnz, i;
4226:   PetscBool       nooffprocentries;
4227:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)mat->data;
4228:   Mat_SeqAIJ     *Ad  = (Mat_SeqAIJ *)Aij->A->data;
4229:   PetscScalar    *ad, *ao;
4230:   PetscInt        ldi, Iii, md;
4231:   const PetscInt *Adi = Ad->i;
4232:   PetscInt       *ld  = Aij->ld;

4234:   PetscFunctionBegin;
4235:   PetscCheck(Ii[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
4236:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
4237:   PetscCheck(m == mat->rmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Local number of rows cannot change from call to MatUpdateMPIAIJWithArrays()");
4238:   PetscCheck(n == mat->cmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Local number of columns cannot change from call to MatUpdateMPIAIJWithArrays()");

4240:   PetscCall(MatSeqAIJGetArrayWrite(Aij->A, &ad));
4241:   PetscCall(MatSeqAIJGetArrayWrite(Aij->B, &ao));

4243:   for (i = 0; i < m; i++) {
4244:     nnz = Ii[i + 1] - Ii[i];
4245:     Iii = Ii[i];
4246:     ldi = ld[i];
4247:     md  = Adi[i + 1] - Adi[i];
4248:     PetscCall(PetscArraycpy(ao, v + Iii, ldi));
4249:     PetscCall(PetscArraycpy(ad, v + Iii + ldi, md));
4250:     PetscCall(PetscArraycpy(ao + ldi, v + Iii + ldi + md, nnz - ldi - md));
4251:     ad += md;
4252:     ao += nnz - md;
4253:   }
4254:   nooffprocentries      = mat->nooffprocentries;
4255:   mat->nooffprocentries = PETSC_TRUE;
4256:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->A, &ad));
4257:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->B, &ao));
4258:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->A));
4259:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->B));
4260:   PetscCall(PetscObjectStateIncrease((PetscObject)mat));
4261:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
4262:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
4263:   mat->nooffprocentries = nooffprocentries;
4264:   PetscFunctionReturn(PETSC_SUCCESS);
4265: }

4267: /*@
4268:   MatUpdateMPIAIJWithArray - updates an `MATMPIAIJ` matrix using an array that contains the nonzero values

4270:   Collective

4272:   Input Parameters:
4273: + mat - the matrix
4274: - v   - matrix values, stored by row

4276:   Level: intermediate

4278:   Note:
4279:   The matrix must have been obtained with `MatCreateMPIAIJWithArrays()` or `MatMPIAIJSetPreallocationCSR()`

4281: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4282:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArrays()`
4283: @*/
4284: PetscErrorCode MatUpdateMPIAIJWithArray(Mat mat, const PetscScalar v[])
4285: {
4286:   PetscInt        nnz, i, m;
4287:   PetscBool       nooffprocentries;
4288:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)mat->data;
4289:   Mat_SeqAIJ     *Ad  = (Mat_SeqAIJ *)Aij->A->data;
4290:   Mat_SeqAIJ     *Ao  = (Mat_SeqAIJ *)Aij->B->data;
4291:   PetscScalar    *ad, *ao;
4292:   const PetscInt *Adi = Ad->i, *Adj = Ao->i;
4293:   PetscInt        ldi, Iii, md;
4294:   PetscInt       *ld = Aij->ld;

4296:   PetscFunctionBegin;
4297:   m = mat->rmap->n;

4299:   PetscCall(MatSeqAIJGetArrayWrite(Aij->A, &ad));
4300:   PetscCall(MatSeqAIJGetArrayWrite(Aij->B, &ao));
4301:   Iii = 0;
4302:   for (i = 0; i < m; i++) {
4303:     nnz = Adi[i + 1] - Adi[i] + Adj[i + 1] - Adj[i];
4304:     ldi = ld[i];
4305:     md  = Adi[i + 1] - Adi[i];
4306:     PetscCall(PetscArraycpy(ao, v + Iii, ldi));
4307:     PetscCall(PetscArraycpy(ad, v + Iii + ldi, md));
4308:     PetscCall(PetscArraycpy(ao + ldi, v + Iii + ldi + md, nnz - ldi - md));
4309:     ad += md;
4310:     ao += nnz - md;
4311:     Iii += nnz;
4312:   }
4313:   nooffprocentries      = mat->nooffprocentries;
4314:   mat->nooffprocentries = PETSC_TRUE;
4315:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->A, &ad));
4316:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->B, &ao));
4317:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->A));
4318:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->B));
4319:   PetscCall(PetscObjectStateIncrease((PetscObject)mat));
4320:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
4321:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
4322:   mat->nooffprocentries = nooffprocentries;
4323:   PetscFunctionReturn(PETSC_SUCCESS);
4324: }

4326: /*@C
4327:   MatCreateAIJ - Creates a sparse parallel matrix in `MATAIJ` format
4328:   (the default parallel PETSc format).  For good matrix assembly performance
4329:   the user should preallocate the matrix storage by setting the parameters
4330:   `d_nz` (or `d_nnz`) and `o_nz` (or `o_nnz`).

4332:   Collective

4334:   Input Parameters:
4335: + comm  - MPI communicator
4336: . m     - number of local rows (or `PETSC_DECIDE` to have calculated if M is given)
4337:            This value should be the same as the local size used in creating the
4338:            y vector for the matrix-vector product y = Ax.
4339: . n     - This value should be the same as the local size used in creating the
4340:        x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4341:        calculated if N is given) For square matrices n is almost always m.
4342: . M     - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4343: . N     - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4344: . d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4345:            (same value is used for all local rows)
4346: . d_nnz - array containing the number of nonzeros in the various rows of the
4347:            DIAGONAL portion of the local submatrix (possibly different for each row)
4348:            or `NULL`, if `d_nz` is used to specify the nonzero structure.
4349:            The size of this array is equal to the number of local rows, i.e 'm'.
4350: . o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4351:            submatrix (same value is used for all local rows).
4352: - o_nnz - array containing the number of nonzeros in the various rows of the
4353:            OFF-DIAGONAL portion of the local submatrix (possibly different for
4354:            each row) or `NULL`, if `o_nz` is used to specify the nonzero
4355:            structure. The size of this array is equal to the number
4356:            of local rows, i.e 'm'.

4358:   Output Parameter:
4359: . A - the matrix

4361:   Options Database Keys:
4362: + -mat_no_inode                     - Do not use inodes
4363: . -mat_inode_limit <limit>          - Sets inode limit (max limit=5)
4364: - -matmult_vecscatter_view <viewer> - View the vecscatter (i.e., communication pattern) used in `MatMult()` of sparse parallel matrices.
4365:         See viewer types in manual of `MatView()`. Of them, ascii_matlab, draw or binary cause the vecscatter be viewed as a matrix.
4366:         Entry (i,j) is the size of message (in bytes) rank i sends to rank j in one `MatMult()` call.

4368:   Level: intermediate

4370:   Notes:
4371:   It is recommended that one use `MatCreateFromOptions()` or the `MatCreate()`, `MatSetType()` and/or `MatSetFromOptions()`,
4372:   MatXXXXSetPreallocation() paradigm instead of this routine directly.
4373:   [MatXXXXSetPreallocation() is, for example, `MatSeqAIJSetPreallocation()`]

4375:   If the *_nnz parameter is given then the *_nz parameter is ignored

4377:   The `m`,`n`,`M`,`N` parameters specify the size of the matrix, and its partitioning across
4378:   processors, while `d_nz`,`d_nnz`,`o_nz`,`o_nnz` parameters specify the approximate
4379:   storage requirements for this matrix.

4381:   If `PETSC_DECIDE` or  `PETSC_DETERMINE` is used for a particular argument on one
4382:   processor than it must be used on all processors that share the object for
4383:   that argument.

4385:   The user MUST specify either the local or global matrix dimensions
4386:   (possibly both).

4388:   The parallel matrix is partitioned across processors such that the
4389:   first m0 rows belong to process 0, the next m1 rows belong to
4390:   process 1, the next m2 rows belong to process 2 etc.. where
4391:   m0,m1,m2,.. are the input parameter 'm'. i.e each processor stores
4392:   values corresponding to [m x N] submatrix.

4394:   The columns are logically partitioned with the n0 columns belonging
4395:   to 0th partition, the next n1 columns belonging to the next
4396:   partition etc.. where n0,n1,n2... are the input parameter 'n'.

4398:   The DIAGONAL portion of the local submatrix on any given processor
4399:   is the submatrix corresponding to the rows and columns m,n
4400:   corresponding to the given processor. i.e diagonal matrix on
4401:   process 0 is [m0 x n0], diagonal matrix on process 1 is [m1 x n1]
4402:   etc. The remaining portion of the local submatrix [m x (N-n)]
4403:   constitute the OFF-DIAGONAL portion. The example below better
4404:   illustrates this concept.

4406:   For a square global matrix we define each processor's diagonal portion
4407:   to be its local rows and the corresponding columns (a square submatrix);
4408:   each processor's off-diagonal portion encompasses the remainder of the
4409:   local matrix (a rectangular submatrix).

4411:   If `o_nnz`, `d_nnz` are specified, then `o_nz`, and `d_nz` are ignored.

4413:   When calling this routine with a single process communicator, a matrix of
4414:   type `MATSEQAIJ` is returned.  If a matrix of type `MATMPIAIJ` is desired for this
4415:   type of communicator, use the construction mechanism
4416: .vb
4417:   MatCreate(..., &A);
4418:   MatSetType(A, MATMPIAIJ);
4419:   MatSetSizes(A, m, n, M, N);
4420:   MatMPIAIJSetPreallocation(A, ...);
4421: .ve

4423:   By default, this format uses inodes (identical nodes) when possible.
4424:   We search for consecutive rows with the same nonzero structure, thereby
4425:   reusing matrix information to achieve increased efficiency.

4427:   Example Usage:
4428:   Consider the following 8x8 matrix with 34 non-zero values, that is
4429:   assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4430:   proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4431:   as follows

4433: .vb
4434:             1  2  0  |  0  3  0  |  0  4
4435:     Proc0   0  5  6  |  7  0  0  |  8  0
4436:             9  0 10  | 11  0  0  | 12  0
4437:     -------------------------------------
4438:            13  0 14  | 15 16 17  |  0  0
4439:     Proc1   0 18  0  | 19 20 21  |  0  0
4440:             0  0  0  | 22 23  0  | 24  0
4441:     -------------------------------------
4442:     Proc2  25 26 27  |  0  0 28  | 29  0
4443:            30  0  0  | 31 32 33  |  0 34
4444: .ve

4446:   This can be represented as a collection of submatrices as

4448: .vb
4449:       A B C
4450:       D E F
4451:       G H I
4452: .ve

4454:   Where the submatrices A,B,C are owned by proc0, D,E,F are
4455:   owned by proc1, G,H,I are owned by proc2.

4457:   The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4458:   The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4459:   The 'M','N' parameters are 8,8, and have the same values on all procs.

4461:   The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4462:   submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4463:   corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4464:   Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4465:   part as `MATSEQAIJ` matrices. For example, proc1 will store [E] as a `MATSEQAIJ`
4466:   matrix, ans [DF] as another SeqAIJ matrix.

4468:   When `d_nz`, `o_nz` parameters are specified, `d_nz` storage elements are
4469:   allocated for every row of the local diagonal submatrix, and `o_nz`
4470:   storage locations are allocated for every row of the OFF-DIAGONAL submat.
4471:   One way to choose `d_nz` and `o_nz` is to use the max nonzerors per local
4472:   rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4473:   In this case, the values of `d_nz`,`o_nz` are
4474: .vb
4475:      proc0  dnz = 2, o_nz = 2
4476:      proc1  dnz = 3, o_nz = 2
4477:      proc2  dnz = 1, o_nz = 4
4478: .ve
4479:   We are allocating m*(`d_nz`+`o_nz`) storage locations for every proc. This
4480:   translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4481:   for proc3. i.e we are using 12+15+10=37 storage locations to store
4482:   34 values.

4484:   When `d_nnz`, `o_nnz` parameters are specified, the storage is specified
4485:   for every row, corresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4486:   In the above case the values for d_nnz,o_nnz are
4487: .vb
4488:      proc0 d_nnz = [2,2,2] and o_nnz = [2,2,2]
4489:      proc1 d_nnz = [3,3,2] and o_nnz = [2,1,1]
4490:      proc2 d_nnz = [1,1]   and o_nnz = [4,4]
4491: .ve
4492:   Here the space allocated is sum of all the above values i.e 34, and
4493:   hence pre-allocation is perfect.

4495: .seealso: [](ch_matrices), `Mat`, [Sparse Matrix Creation](sec_matsparse), `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4496:           `MATMPIAIJ`, `MatCreateMPIAIJWithArrays()`
4497: @*/
4498: 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)
4499: {
4500:   PetscMPIInt size;

4502:   PetscFunctionBegin;
4503:   PetscCall(MatCreate(comm, A));
4504:   PetscCall(MatSetSizes(*A, m, n, M, N));
4505:   PetscCallMPI(MPI_Comm_size(comm, &size));
4506:   if (size > 1) {
4507:     PetscCall(MatSetType(*A, MATMPIAIJ));
4508:     PetscCall(MatMPIAIJSetPreallocation(*A, d_nz, d_nnz, o_nz, o_nnz));
4509:   } else {
4510:     PetscCall(MatSetType(*A, MATSEQAIJ));
4511:     PetscCall(MatSeqAIJSetPreallocation(*A, d_nz, d_nnz));
4512:   }
4513:   PetscFunctionReturn(PETSC_SUCCESS);
4514: }

4516: /*MC
4517:     MatMPIAIJGetSeqAIJF90 - Returns the local pieces of this distributed matrix

4519:     Synopsis:
4520:     MatMPIAIJGetSeqAIJF90(Mat A, Mat Ad, Mat Ao, {PetscInt, pointer :: colmap(:)},integer ierr)

4522:     Not Collective

4524:     Input Parameter:
4525: .   A - the `MATMPIAIJ` matrix

4527:     Output Parameters:
4528: +   Ad - the diagonal portion of the matrix
4529: .   Ao - the off-diagonal portion of the matrix
4530: .   colmap - An array mapping local column numbers of `Ao` to global column numbers of the parallel matrix
4531: -   ierr - error code

4533:      Level: advanced

4535:     Note:
4536:     Use  `MatMPIAIJRestoreSeqAIJF90()` when you no longer need access to the matrices and `colmap`

4538: .seealso: [](ch_matrices), `Mat`, [](sec_fortranarrays), `Mat`, `MATMPIAIJ`, `MatMPIAIJGetSeqAIJ()`, `MatMPIAIJRestoreSeqAIJF90()`
4539: M*/

4541: /*MC
4542:     MatMPIAIJRestoreSeqAIJF90 - call after `MatMPIAIJGetSeqAIJF90()` when you no longer need access to the matrices and `colmap`

4544:     Synopsis:
4545:     MatMPIAIJRestoreSeqAIJF90(Mat A, Mat Ad, Mat Ao, {PetscInt, pointer :: colmap(:)},integer ierr)

4547:     Not Collective

4549:     Input Parameters:
4550: +   A - the `MATMPIAIJ` matrix
4551: .   Ad - the diagonal portion of the matrix
4552: .   Ao - the off-diagonal portion of the matrix
4553: .   colmap - An array mapping local column numbers of `Ao` to global column numbers of the parallel matrix
4554: -   ierr - error code

4556:      Level: advanced

4558: .seealso: [](ch_matrices), `Mat`, [](sec_fortranarrays), `Mat`, `MATMPIAIJ`, `MatMPIAIJGetSeqAIJ()`, `MatMPIAIJGetSeqAIJF90()`
4559: M*/

4561: /*@C
4562:   MatMPIAIJGetSeqAIJ - Returns the local pieces of this distributed matrix

4564:   Not Collective

4566:   Input Parameter:
4567: . A - The `MATMPIAIJ` matrix

4569:   Output Parameters:
4570: + Ad     - The local diagonal block as a `MATSEQAIJ` matrix
4571: . Ao     - The local off-diagonal block as a `MATSEQAIJ` matrix
4572: - colmap - An array mapping local column numbers of `Ao` to global column numbers of the parallel matrix

4574:   Level: intermediate

4576:   Note:
4577:   The rows in `Ad` and `Ao` are in [0, Nr), where Nr is the number of local rows on this process. The columns
4578:   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
4579:   the number of nonzero columns in the local off-diagonal piece of the matrix `A`. The array colmap maps these
4580:   local column numbers to global column numbers in the original matrix.

4582:   Fortran Notes:
4583:   `MatMPIAIJGetSeqAIJ()` Fortran binding is deprecated (since PETSc 3.19), use `MatMPIAIJGetSeqAIJF90()`

4585: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatMPIAIJGetSeqAIJF90()`, `MatMPIAIJRestoreSeqAIJF90()`, `MatMPIAIJGetLocalMat()`, `MatMPIAIJGetLocalMatCondensed()`, `MatCreateAIJ()`, `MATSEQAIJ`
4586: @*/
4587: PetscErrorCode MatMPIAIJGetSeqAIJ(Mat A, Mat *Ad, Mat *Ao, const PetscInt *colmap[])
4588: {
4589:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
4590:   PetscBool   flg;

4592:   PetscFunctionBegin;
4593:   PetscCall(PetscStrbeginswith(((PetscObject)A)->type_name, MATMPIAIJ, &flg));
4594:   PetscCheck(flg, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "This function requires a MATMPIAIJ matrix as input");
4595:   if (Ad) *Ad = a->A;
4596:   if (Ao) *Ao = a->B;
4597:   if (colmap) *colmap = a->garray;
4598:   PetscFunctionReturn(PETSC_SUCCESS);
4599: }

4601: PetscErrorCode MatCreateMPIMatConcatenateSeqMat_MPIAIJ(MPI_Comm comm, Mat inmat, PetscInt n, MatReuse scall, Mat *outmat)
4602: {
4603:   PetscInt     m, N, i, rstart, nnz, Ii;
4604:   PetscInt    *indx;
4605:   PetscScalar *values;
4606:   MatType      rootType;

4608:   PetscFunctionBegin;
4609:   PetscCall(MatGetSize(inmat, &m, &N));
4610:   if (scall == MAT_INITIAL_MATRIX) { /* symbolic phase */
4611:     PetscInt *dnz, *onz, sum, bs, cbs;

4613:     if (n == PETSC_DECIDE) PetscCall(PetscSplitOwnership(comm, &n, &N));
4614:     /* Check sum(n) = N */
4615:     PetscCall(MPIU_Allreduce(&n, &sum, 1, MPIU_INT, MPI_SUM, comm));
4616:     PetscCheck(sum == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Sum of local columns %" PetscInt_FMT " != global columns %" PetscInt_FMT, sum, N);

4618:     PetscCallMPI(MPI_Scan(&m, &rstart, 1, MPIU_INT, MPI_SUM, comm));
4619:     rstart -= m;

4621:     MatPreallocateBegin(comm, m, n, dnz, onz);
4622:     for (i = 0; i < m; i++) {
4623:       PetscCall(MatGetRow_SeqAIJ(inmat, i, &nnz, &indx, NULL));
4624:       PetscCall(MatPreallocateSet(i + rstart, nnz, indx, dnz, onz));
4625:       PetscCall(MatRestoreRow_SeqAIJ(inmat, i, &nnz, &indx, NULL));
4626:     }

4628:     PetscCall(MatCreate(comm, outmat));
4629:     PetscCall(MatSetSizes(*outmat, m, n, PETSC_DETERMINE, PETSC_DETERMINE));
4630:     PetscCall(MatGetBlockSizes(inmat, &bs, &cbs));
4631:     PetscCall(MatSetBlockSizes(*outmat, bs, cbs));
4632:     PetscCall(MatGetRootType_Private(inmat, &rootType));
4633:     PetscCall(MatSetType(*outmat, rootType));
4634:     PetscCall(MatSeqAIJSetPreallocation(*outmat, 0, dnz));
4635:     PetscCall(MatMPIAIJSetPreallocation(*outmat, 0, dnz, 0, onz));
4636:     MatPreallocateEnd(dnz, onz);
4637:     PetscCall(MatSetOption(*outmat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
4638:   }

4640:   /* numeric phase */
4641:   PetscCall(MatGetOwnershipRange(*outmat, &rstart, NULL));
4642:   for (i = 0; i < m; i++) {
4643:     PetscCall(MatGetRow_SeqAIJ(inmat, i, &nnz, &indx, &values));
4644:     Ii = i + rstart;
4645:     PetscCall(MatSetValues(*outmat, 1, &Ii, nnz, indx, values, INSERT_VALUES));
4646:     PetscCall(MatRestoreRow_SeqAIJ(inmat, i, &nnz, &indx, &values));
4647:   }
4648:   PetscCall(MatAssemblyBegin(*outmat, MAT_FINAL_ASSEMBLY));
4649:   PetscCall(MatAssemblyEnd(*outmat, MAT_FINAL_ASSEMBLY));
4650:   PetscFunctionReturn(PETSC_SUCCESS);
4651: }

4653: static PetscErrorCode MatDestroy_MPIAIJ_SeqsToMPI(void *data)
4654: {
4655:   Mat_Merge_SeqsToMPI *merge = (Mat_Merge_SeqsToMPI *)data;

4657:   PetscFunctionBegin;
4658:   if (!merge) PetscFunctionReturn(PETSC_SUCCESS);
4659:   PetscCall(PetscFree(merge->id_r));
4660:   PetscCall(PetscFree(merge->len_s));
4661:   PetscCall(PetscFree(merge->len_r));
4662:   PetscCall(PetscFree(merge->bi));
4663:   PetscCall(PetscFree(merge->bj));
4664:   PetscCall(PetscFree(merge->buf_ri[0]));
4665:   PetscCall(PetscFree(merge->buf_ri));
4666:   PetscCall(PetscFree(merge->buf_rj[0]));
4667:   PetscCall(PetscFree(merge->buf_rj));
4668:   PetscCall(PetscFree(merge->coi));
4669:   PetscCall(PetscFree(merge->coj));
4670:   PetscCall(PetscFree(merge->owners_co));
4671:   PetscCall(PetscLayoutDestroy(&merge->rowmap));
4672:   PetscCall(PetscFree(merge));
4673:   PetscFunctionReturn(PETSC_SUCCESS);
4674: }

4676: #include <../src/mat/utils/freespace.h>
4677: #include <petscbt.h>

4679: PetscErrorCode MatCreateMPIAIJSumSeqAIJNumeric(Mat seqmat, Mat mpimat)
4680: {
4681:   MPI_Comm             comm;
4682:   Mat_SeqAIJ          *a = (Mat_SeqAIJ *)seqmat->data;
4683:   PetscMPIInt          size, rank, taga, *len_s;
4684:   PetscInt             N = mpimat->cmap->N, i, j, *owners, *ai = a->i, *aj;
4685:   PetscInt             proc, m;
4686:   PetscInt           **buf_ri, **buf_rj;
4687:   PetscInt             k, anzi, *bj_i, *bi, *bj, arow, bnzi, nextaj;
4688:   PetscInt             nrows, **buf_ri_k, **nextrow, **nextai;
4689:   MPI_Request         *s_waits, *r_waits;
4690:   MPI_Status          *status;
4691:   const MatScalar     *aa, *a_a;
4692:   MatScalar          **abuf_r, *ba_i;
4693:   Mat_Merge_SeqsToMPI *merge;
4694:   PetscContainer       container;

4696:   PetscFunctionBegin;
4697:   PetscCall(PetscObjectGetComm((PetscObject)mpimat, &comm));
4698:   PetscCall(PetscLogEventBegin(MAT_Seqstompinum, seqmat, 0, 0, 0));

4700:   PetscCallMPI(MPI_Comm_size(comm, &size));
4701:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

4703:   PetscCall(PetscObjectQuery((PetscObject)mpimat, "MatMergeSeqsToMPI", (PetscObject *)&container));
4704:   PetscCheck(container, PetscObjectComm((PetscObject)mpimat), PETSC_ERR_PLIB, "Mat not created from MatCreateMPIAIJSumSeqAIJSymbolic");
4705:   PetscCall(PetscContainerGetPointer(container, (void **)&merge));
4706:   PetscCall(MatSeqAIJGetArrayRead(seqmat, &a_a));
4707:   aa = a_a;

4709:   bi     = merge->bi;
4710:   bj     = merge->bj;
4711:   buf_ri = merge->buf_ri;
4712:   buf_rj = merge->buf_rj;

4714:   PetscCall(PetscMalloc1(size, &status));
4715:   owners = merge->rowmap->range;
4716:   len_s  = merge->len_s;

4718:   /* send and recv matrix values */
4719:   PetscCall(PetscObjectGetNewTag((PetscObject)mpimat, &taga));
4720:   PetscCall(PetscPostIrecvScalar(comm, taga, merge->nrecv, merge->id_r, merge->len_r, &abuf_r, &r_waits));

4722:   PetscCall(PetscMalloc1(merge->nsend + 1, &s_waits));
4723:   for (proc = 0, k = 0; proc < size; proc++) {
4724:     if (!len_s[proc]) continue;
4725:     i = owners[proc];
4726:     PetscCallMPI(MPI_Isend(aa + ai[i], len_s[proc], MPIU_MATSCALAR, proc, taga, comm, s_waits + k));
4727:     k++;
4728:   }

4730:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, r_waits, status));
4731:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, s_waits, status));
4732:   PetscCall(PetscFree(status));

4734:   PetscCall(PetscFree(s_waits));
4735:   PetscCall(PetscFree(r_waits));

4737:   /* insert mat values of mpimat */
4738:   PetscCall(PetscMalloc1(N, &ba_i));
4739:   PetscCall(PetscMalloc3(merge->nrecv, &buf_ri_k, merge->nrecv, &nextrow, merge->nrecv, &nextai));

4741:   for (k = 0; k < merge->nrecv; k++) {
4742:     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4743:     nrows       = *(buf_ri_k[k]);
4744:     nextrow[k]  = buf_ri_k[k] + 1;           /* next row number of k-th recved i-structure */
4745:     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* points to the next i-structure of k-th recved i-structure  */
4746:   }

4748:   /* set values of ba */
4749:   m = merge->rowmap->n;
4750:   for (i = 0; i < m; i++) {
4751:     arow = owners[rank] + i;
4752:     bj_i = bj + bi[i]; /* col indices of the i-th row of mpimat */
4753:     bnzi = bi[i + 1] - bi[i];
4754:     PetscCall(PetscArrayzero(ba_i, bnzi));

4756:     /* add local non-zero vals of this proc's seqmat into ba */
4757:     anzi   = ai[arow + 1] - ai[arow];
4758:     aj     = a->j + ai[arow];
4759:     aa     = a_a + ai[arow];
4760:     nextaj = 0;
4761:     for (j = 0; nextaj < anzi; j++) {
4762:       if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4763:         ba_i[j] += aa[nextaj++];
4764:       }
4765:     }

4767:     /* add received vals into ba */
4768:     for (k = 0; k < merge->nrecv; k++) { /* k-th received message */
4769:       /* i-th row */
4770:       if (i == *nextrow[k]) {
4771:         anzi   = *(nextai[k] + 1) - *nextai[k];
4772:         aj     = buf_rj[k] + *(nextai[k]);
4773:         aa     = abuf_r[k] + *(nextai[k]);
4774:         nextaj = 0;
4775:         for (j = 0; nextaj < anzi; j++) {
4776:           if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4777:             ba_i[j] += aa[nextaj++];
4778:           }
4779:         }
4780:         nextrow[k]++;
4781:         nextai[k]++;
4782:       }
4783:     }
4784:     PetscCall(MatSetValues(mpimat, 1, &arow, bnzi, bj_i, ba_i, INSERT_VALUES));
4785:   }
4786:   PetscCall(MatSeqAIJRestoreArrayRead(seqmat, &a_a));
4787:   PetscCall(MatAssemblyBegin(mpimat, MAT_FINAL_ASSEMBLY));
4788:   PetscCall(MatAssemblyEnd(mpimat, MAT_FINAL_ASSEMBLY));

4790:   PetscCall(PetscFree(abuf_r[0]));
4791:   PetscCall(PetscFree(abuf_r));
4792:   PetscCall(PetscFree(ba_i));
4793:   PetscCall(PetscFree3(buf_ri_k, nextrow, nextai));
4794:   PetscCall(PetscLogEventEnd(MAT_Seqstompinum, seqmat, 0, 0, 0));
4795:   PetscFunctionReturn(PETSC_SUCCESS);
4796: }

4798: PetscErrorCode MatCreateMPIAIJSumSeqAIJSymbolic(MPI_Comm comm, Mat seqmat, PetscInt m, PetscInt n, Mat *mpimat)
4799: {
4800:   Mat                  B_mpi;
4801:   Mat_SeqAIJ          *a = (Mat_SeqAIJ *)seqmat->data;
4802:   PetscMPIInt          size, rank, tagi, tagj, *len_s, *len_si, *len_ri;
4803:   PetscInt           **buf_rj, **buf_ri, **buf_ri_k;
4804:   PetscInt             M = seqmat->rmap->n, N = seqmat->cmap->n, i, *owners, *ai = a->i, *aj = a->j;
4805:   PetscInt             len, proc, *dnz, *onz, bs, cbs;
4806:   PetscInt             k, anzi, *bi, *bj, *lnk, nlnk, arow, bnzi;
4807:   PetscInt             nrows, *buf_s, *buf_si, *buf_si_i, **nextrow, **nextai;
4808:   MPI_Request         *si_waits, *sj_waits, *ri_waits, *rj_waits;
4809:   MPI_Status          *status;
4810:   PetscFreeSpaceList   free_space = NULL, current_space = NULL;
4811:   PetscBT              lnkbt;
4812:   Mat_Merge_SeqsToMPI *merge;
4813:   PetscContainer       container;

4815:   PetscFunctionBegin;
4816:   PetscCall(PetscLogEventBegin(MAT_Seqstompisym, seqmat, 0, 0, 0));

4818:   /* make sure it is a PETSc comm */
4819:   PetscCall(PetscCommDuplicate(comm, &comm, NULL));
4820:   PetscCallMPI(MPI_Comm_size(comm, &size));
4821:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

4823:   PetscCall(PetscNew(&merge));
4824:   PetscCall(PetscMalloc1(size, &status));

4826:   /* determine row ownership */
4827:   PetscCall(PetscLayoutCreate(comm, &merge->rowmap));
4828:   PetscCall(PetscLayoutSetLocalSize(merge->rowmap, m));
4829:   PetscCall(PetscLayoutSetSize(merge->rowmap, M));
4830:   PetscCall(PetscLayoutSetBlockSize(merge->rowmap, 1));
4831:   PetscCall(PetscLayoutSetUp(merge->rowmap));
4832:   PetscCall(PetscMalloc1(size, &len_si));
4833:   PetscCall(PetscMalloc1(size, &merge->len_s));

4835:   m      = merge->rowmap->n;
4836:   owners = merge->rowmap->range;

4838:   /* determine the number of messages to send, their lengths */
4839:   len_s = merge->len_s;

4841:   len          = 0; /* length of buf_si[] */
4842:   merge->nsend = 0;
4843:   for (proc = 0; proc < size; proc++) {
4844:     len_si[proc] = 0;
4845:     if (proc == rank) {
4846:       len_s[proc] = 0;
4847:     } else {
4848:       len_si[proc] = owners[proc + 1] - owners[proc] + 1;
4849:       len_s[proc]  = ai[owners[proc + 1]] - ai[owners[proc]]; /* num of rows to be sent to [proc] */
4850:     }
4851:     if (len_s[proc]) {
4852:       merge->nsend++;
4853:       nrows = 0;
4854:       for (i = owners[proc]; i < owners[proc + 1]; i++) {
4855:         if (ai[i + 1] > ai[i]) nrows++;
4856:       }
4857:       len_si[proc] = 2 * (nrows + 1);
4858:       len += len_si[proc];
4859:     }
4860:   }

4862:   /* determine the number and length of messages to receive for ij-structure */
4863:   PetscCall(PetscGatherNumberOfMessages(comm, NULL, len_s, &merge->nrecv));
4864:   PetscCall(PetscGatherMessageLengths2(comm, merge->nsend, merge->nrecv, len_s, len_si, &merge->id_r, &merge->len_r, &len_ri));

4866:   /* post the Irecv of j-structure */
4867:   PetscCall(PetscCommGetNewTag(comm, &tagj));
4868:   PetscCall(PetscPostIrecvInt(comm, tagj, merge->nrecv, merge->id_r, merge->len_r, &buf_rj, &rj_waits));

4870:   /* post the Isend of j-structure */
4871:   PetscCall(PetscMalloc2(merge->nsend, &si_waits, merge->nsend, &sj_waits));

4873:   for (proc = 0, k = 0; proc < size; proc++) {
4874:     if (!len_s[proc]) continue;
4875:     i = owners[proc];
4876:     PetscCallMPI(MPI_Isend(aj + ai[i], len_s[proc], MPIU_INT, proc, tagj, comm, sj_waits + k));
4877:     k++;
4878:   }

4880:   /* receives and sends of j-structure are complete */
4881:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, rj_waits, status));
4882:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, sj_waits, status));

4884:   /* send and recv i-structure */
4885:   PetscCall(PetscCommGetNewTag(comm, &tagi));
4886:   PetscCall(PetscPostIrecvInt(comm, tagi, merge->nrecv, merge->id_r, len_ri, &buf_ri, &ri_waits));

4888:   PetscCall(PetscMalloc1(len + 1, &buf_s));
4889:   buf_si = buf_s; /* points to the beginning of k-th msg to be sent */
4890:   for (proc = 0, k = 0; proc < size; proc++) {
4891:     if (!len_s[proc]) continue;
4892:     /* form outgoing message for i-structure:
4893:          buf_si[0]:                 nrows to be sent
4894:                [1:nrows]:           row index (global)
4895:                [nrows+1:2*nrows+1]: i-structure index
4896:     */
4897:     nrows       = len_si[proc] / 2 - 1;
4898:     buf_si_i    = buf_si + nrows + 1;
4899:     buf_si[0]   = nrows;
4900:     buf_si_i[0] = 0;
4901:     nrows       = 0;
4902:     for (i = owners[proc]; i < owners[proc + 1]; i++) {
4903:       anzi = ai[i + 1] - ai[i];
4904:       if (anzi) {
4905:         buf_si_i[nrows + 1] = buf_si_i[nrows] + anzi; /* i-structure */
4906:         buf_si[nrows + 1]   = i - owners[proc];       /* local row index */
4907:         nrows++;
4908:       }
4909:     }
4910:     PetscCallMPI(MPI_Isend(buf_si, len_si[proc], MPIU_INT, proc, tagi, comm, si_waits + k));
4911:     k++;
4912:     buf_si += len_si[proc];
4913:   }

4915:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, ri_waits, status));
4916:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, si_waits, status));

4918:   PetscCall(PetscInfo(seqmat, "nsend: %d, nrecv: %d\n", merge->nsend, merge->nrecv));
4919:   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]));

4921:   PetscCall(PetscFree(len_si));
4922:   PetscCall(PetscFree(len_ri));
4923:   PetscCall(PetscFree(rj_waits));
4924:   PetscCall(PetscFree2(si_waits, sj_waits));
4925:   PetscCall(PetscFree(ri_waits));
4926:   PetscCall(PetscFree(buf_s));
4927:   PetscCall(PetscFree(status));

4929:   /* compute a local seq matrix in each processor */
4930:   /* allocate bi array and free space for accumulating nonzero column info */
4931:   PetscCall(PetscMalloc1(m + 1, &bi));
4932:   bi[0] = 0;

4934:   /* create and initialize a linked list */
4935:   nlnk = N + 1;
4936:   PetscCall(PetscLLCreate(N, N, nlnk, lnk, lnkbt));

4938:   /* initial FreeSpace size is 2*(num of local nnz(seqmat)) */
4939:   len = ai[owners[rank + 1]] - ai[owners[rank]];
4940:   PetscCall(PetscFreeSpaceGet(PetscIntMultTruncate(2, len) + 1, &free_space));

4942:   current_space = free_space;

4944:   /* determine symbolic info for each local row */
4945:   PetscCall(PetscMalloc3(merge->nrecv, &buf_ri_k, merge->nrecv, &nextrow, merge->nrecv, &nextai));

4947:   for (k = 0; k < merge->nrecv; k++) {
4948:     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4949:     nrows       = *buf_ri_k[k];
4950:     nextrow[k]  = buf_ri_k[k] + 1;           /* next row number of k-th recved i-structure */
4951:     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* points to the next i-structure of k-th recved i-structure  */
4952:   }

4954:   MatPreallocateBegin(comm, m, n, dnz, onz);
4955:   len = 0;
4956:   for (i = 0; i < m; i++) {
4957:     bnzi = 0;
4958:     /* add local non-zero cols of this proc's seqmat into lnk */
4959:     arow = owners[rank] + i;
4960:     anzi = ai[arow + 1] - ai[arow];
4961:     aj   = a->j + ai[arow];
4962:     PetscCall(PetscLLAddSorted(anzi, aj, N, &nlnk, lnk, lnkbt));
4963:     bnzi += nlnk;
4964:     /* add received col data into lnk */
4965:     for (k = 0; k < merge->nrecv; k++) { /* k-th received message */
4966:       if (i == *nextrow[k]) {            /* i-th row */
4967:         anzi = *(nextai[k] + 1) - *nextai[k];
4968:         aj   = buf_rj[k] + *nextai[k];
4969:         PetscCall(PetscLLAddSorted(anzi, aj, N, &nlnk, lnk, lnkbt));
4970:         bnzi += nlnk;
4971:         nextrow[k]++;
4972:         nextai[k]++;
4973:       }
4974:     }
4975:     if (len < bnzi) len = bnzi; /* =max(bnzi) */

4977:     /* if free space is not available, make more free space */
4978:     if (current_space->local_remaining < bnzi) PetscCall(PetscFreeSpaceGet(PetscIntSumTruncate(bnzi, current_space->total_array_size), &current_space));
4979:     /* copy data into free space, then initialize lnk */
4980:     PetscCall(PetscLLClean(N, N, bnzi, lnk, current_space->array, lnkbt));
4981:     PetscCall(MatPreallocateSet(i + owners[rank], bnzi, current_space->array, dnz, onz));

4983:     current_space->array += bnzi;
4984:     current_space->local_used += bnzi;
4985:     current_space->local_remaining -= bnzi;

4987:     bi[i + 1] = bi[i] + bnzi;
4988:   }

4990:   PetscCall(PetscFree3(buf_ri_k, nextrow, nextai));

4992:   PetscCall(PetscMalloc1(bi[m] + 1, &bj));
4993:   PetscCall(PetscFreeSpaceContiguous(&free_space, bj));
4994:   PetscCall(PetscLLDestroy(lnk, lnkbt));

4996:   /* create symbolic parallel matrix B_mpi */
4997:   PetscCall(MatGetBlockSizes(seqmat, &bs, &cbs));
4998:   PetscCall(MatCreate(comm, &B_mpi));
4999:   if (n == PETSC_DECIDE) {
5000:     PetscCall(MatSetSizes(B_mpi, m, n, PETSC_DETERMINE, N));
5001:   } else {
5002:     PetscCall(MatSetSizes(B_mpi, m, n, PETSC_DETERMINE, PETSC_DETERMINE));
5003:   }
5004:   PetscCall(MatSetBlockSizes(B_mpi, bs, cbs));
5005:   PetscCall(MatSetType(B_mpi, MATMPIAIJ));
5006:   PetscCall(MatMPIAIJSetPreallocation(B_mpi, 0, dnz, 0, onz));
5007:   MatPreallocateEnd(dnz, onz);
5008:   PetscCall(MatSetOption(B_mpi, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_FALSE));

5010:   /* B_mpi is not ready for use - assembly will be done by MatCreateMPIAIJSumSeqAIJNumeric() */
5011:   B_mpi->assembled = PETSC_FALSE;
5012:   merge->bi        = bi;
5013:   merge->bj        = bj;
5014:   merge->buf_ri    = buf_ri;
5015:   merge->buf_rj    = buf_rj;
5016:   merge->coi       = NULL;
5017:   merge->coj       = NULL;
5018:   merge->owners_co = NULL;

5020:   PetscCall(PetscCommDestroy(&comm));

5022:   /* attach the supporting struct to B_mpi for reuse */
5023:   PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &container));
5024:   PetscCall(PetscContainerSetPointer(container, merge));
5025:   PetscCall(PetscContainerSetUserDestroy(container, MatDestroy_MPIAIJ_SeqsToMPI));
5026:   PetscCall(PetscObjectCompose((PetscObject)B_mpi, "MatMergeSeqsToMPI", (PetscObject)container));
5027:   PetscCall(PetscContainerDestroy(&container));
5028:   *mpimat = B_mpi;

5030:   PetscCall(PetscLogEventEnd(MAT_Seqstompisym, seqmat, 0, 0, 0));
5031:   PetscFunctionReturn(PETSC_SUCCESS);
5032: }

5034: /*@C
5035:   MatCreateMPIAIJSumSeqAIJ - Creates a `MATMPIAIJ` matrix by adding sequential
5036:   matrices from each processor

5038:   Collective

5040:   Input Parameters:
5041: + comm   - the communicators the parallel matrix will live on
5042: . seqmat - the input sequential matrices
5043: . m      - number of local rows (or `PETSC_DECIDE`)
5044: . n      - number of local columns (or `PETSC_DECIDE`)
5045: - scall  - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5047:   Output Parameter:
5048: . mpimat - the parallel matrix generated

5050:   Level: advanced

5052:   Note:
5053:   The dimensions of the sequential matrix in each processor MUST be the same.
5054:   The input seqmat is included into the container "Mat_Merge_SeqsToMPI", and will be
5055:   destroyed when mpimat is destroyed. Call `PetscObjectQuery()` to access seqmat.

5057: .seealso: [](ch_matrices), `Mat`, `MatCreateAIJ()`
5058: @*/
5059: PetscErrorCode MatCreateMPIAIJSumSeqAIJ(MPI_Comm comm, Mat seqmat, PetscInt m, PetscInt n, MatReuse scall, Mat *mpimat)
5060: {
5061:   PetscMPIInt size;

5063:   PetscFunctionBegin;
5064:   PetscCallMPI(MPI_Comm_size(comm, &size));
5065:   if (size == 1) {
5066:     PetscCall(PetscLogEventBegin(MAT_Seqstompi, seqmat, 0, 0, 0));
5067:     if (scall == MAT_INITIAL_MATRIX) {
5068:       PetscCall(MatDuplicate(seqmat, MAT_COPY_VALUES, mpimat));
5069:     } else {
5070:       PetscCall(MatCopy(seqmat, *mpimat, SAME_NONZERO_PATTERN));
5071:     }
5072:     PetscCall(PetscLogEventEnd(MAT_Seqstompi, seqmat, 0, 0, 0));
5073:     PetscFunctionReturn(PETSC_SUCCESS);
5074:   }
5075:   PetscCall(PetscLogEventBegin(MAT_Seqstompi, seqmat, 0, 0, 0));
5076:   if (scall == MAT_INITIAL_MATRIX) PetscCall(MatCreateMPIAIJSumSeqAIJSymbolic(comm, seqmat, m, n, mpimat));
5077:   PetscCall(MatCreateMPIAIJSumSeqAIJNumeric(seqmat, *mpimat));
5078:   PetscCall(PetscLogEventEnd(MAT_Seqstompi, seqmat, 0, 0, 0));
5079:   PetscFunctionReturn(PETSC_SUCCESS);
5080: }

5082: /*@
5083:   MatAIJGetLocalMat - Creates a `MATSEQAIJ` from a `MATAIJ` matrix.

5085:   Not Collective

5087:   Input Parameter:
5088: . A - the matrix

5090:   Output Parameter:
5091: . A_loc - the local sequential matrix generated

5093:   Level: developer

5095:   Notes:
5096:   The matrix is created by taking `A`'s local rows and putting them into a sequential matrix
5097:   with `mlocal` rows and `n` columns. Where `mlocal` is obtained with `MatGetLocalSize()` and
5098:   `n` is the global column count obtained with `MatGetSize()`

5100:   In other words combines the two parts of a parallel `MATMPIAIJ` matrix on each process to a single matrix.

5102:   For parallel matrices this creates an entirely new matrix. If the matrix is sequential it merely increases the reference count.

5104:   Destroy the matrix with `MatDestroy()`

5106: .seealso: [](ch_matrices), `Mat`, `MatMPIAIJGetLocalMat()`
5107: @*/
5108: PetscErrorCode MatAIJGetLocalMat(Mat A, Mat *A_loc)
5109: {
5110:   PetscBool mpi;

5112:   PetscFunctionBegin;
5113:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATMPIAIJ, &mpi));
5114:   if (mpi) {
5115:     PetscCall(MatMPIAIJGetLocalMat(A, MAT_INITIAL_MATRIX, A_loc));
5116:   } else {
5117:     *A_loc = A;
5118:     PetscCall(PetscObjectReference((PetscObject)*A_loc));
5119:   }
5120:   PetscFunctionReturn(PETSC_SUCCESS);
5121: }

5123: /*@
5124:   MatMPIAIJGetLocalMat - Creates a `MATSEQAIJ` from a `MATMPIAIJ` matrix.

5126:   Not Collective

5128:   Input Parameters:
5129: + A     - the matrix
5130: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5132:   Output Parameter:
5133: . A_loc - the local sequential matrix generated

5135:   Level: developer

5137:   Notes:
5138:   The matrix is created by taking all `A`'s local rows and putting them into a sequential
5139:   matrix with `mlocal` rows and `n` columns.`mlocal` is the row count obtained with
5140:   `MatGetLocalSize()` and `n` is the global column count obtained with `MatGetSize()`.

5142:   In other words combines the two parts of a parallel `MATMPIAIJ` matrix on each process to a single matrix.

5144:   When `A` is sequential and `MAT_INITIAL_MATRIX` is requested, the matrix returned is the diagonal part of `A` (which contains the entire matrix),
5145:   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
5146:   then `MatCopy`(Adiag,*`A_loc`,`SAME_NONZERO_PATTERN`) is called to fill `A_loc`. Thus one can preallocate the appropriate sequential matrix `A_loc`
5147:   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.

5149: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMatCondensed()`, `MatMPIAIJGetLocalMatMerge()`
5150: @*/
5151: PetscErrorCode MatMPIAIJGetLocalMat(Mat A, MatReuse scall, Mat *A_loc)
5152: {
5153:   Mat_MPIAIJ        *mpimat = (Mat_MPIAIJ *)A->data;
5154:   Mat_SeqAIJ        *mat, *a, *b;
5155:   PetscInt          *ai, *aj, *bi, *bj, *cmap = mpimat->garray;
5156:   const PetscScalar *aa, *ba, *aav, *bav;
5157:   PetscScalar       *ca, *cam;
5158:   PetscMPIInt        size;
5159:   PetscInt           am = A->rmap->n, i, j, k, cstart = A->cmap->rstart;
5160:   PetscInt          *ci, *cj, col, ncols_d, ncols_o, jo;
5161:   PetscBool          match;

5163:   PetscFunctionBegin;
5164:   PetscCall(PetscStrbeginswith(((PetscObject)A)->type_name, MATMPIAIJ, &match));
5165:   PetscCheck(match, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Requires MATMPIAIJ matrix as input");
5166:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)A), &size));
5167:   if (size == 1) {
5168:     if (scall == MAT_INITIAL_MATRIX) {
5169:       PetscCall(PetscObjectReference((PetscObject)mpimat->A));
5170:       *A_loc = mpimat->A;
5171:     } else if (scall == MAT_REUSE_MATRIX) {
5172:       PetscCall(MatCopy(mpimat->A, *A_loc, SAME_NONZERO_PATTERN));
5173:     }
5174:     PetscFunctionReturn(PETSC_SUCCESS);
5175:   }

5177:   PetscCall(PetscLogEventBegin(MAT_Getlocalmat, A, 0, 0, 0));
5178:   a  = (Mat_SeqAIJ *)(mpimat->A)->data;
5179:   b  = (Mat_SeqAIJ *)(mpimat->B)->data;
5180:   ai = a->i;
5181:   aj = a->j;
5182:   bi = b->i;
5183:   bj = b->j;
5184:   PetscCall(MatSeqAIJGetArrayRead(mpimat->A, &aav));
5185:   PetscCall(MatSeqAIJGetArrayRead(mpimat->B, &bav));
5186:   aa = aav;
5187:   ba = bav;
5188:   if (scall == MAT_INITIAL_MATRIX) {
5189:     PetscCall(PetscMalloc1(1 + am, &ci));
5190:     ci[0] = 0;
5191:     for (i = 0; i < am; i++) ci[i + 1] = ci[i] + (ai[i + 1] - ai[i]) + (bi[i + 1] - bi[i]);
5192:     PetscCall(PetscMalloc1(1 + ci[am], &cj));
5193:     PetscCall(PetscMalloc1(1 + ci[am], &ca));
5194:     k = 0;
5195:     for (i = 0; i < am; i++) {
5196:       ncols_o = bi[i + 1] - bi[i];
5197:       ncols_d = ai[i + 1] - ai[i];
5198:       /* off-diagonal portion of A */
5199:       for (jo = 0; jo < ncols_o; jo++) {
5200:         col = cmap[*bj];
5201:         if (col >= cstart) break;
5202:         cj[k] = col;
5203:         bj++;
5204:         ca[k++] = *ba++;
5205:       }
5206:       /* diagonal portion of A */
5207:       for (j = 0; j < ncols_d; j++) {
5208:         cj[k]   = cstart + *aj++;
5209:         ca[k++] = *aa++;
5210:       }
5211:       /* off-diagonal portion of A */
5212:       for (j = jo; j < ncols_o; j++) {
5213:         cj[k]   = cmap[*bj++];
5214:         ca[k++] = *ba++;
5215:       }
5216:     }
5217:     /* put together the new matrix */
5218:     PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, am, A->cmap->N, ci, cj, ca, A_loc));
5219:     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5220:     /* Since these are PETSc arrays, change flags to free them as necessary. */
5221:     mat          = (Mat_SeqAIJ *)(*A_loc)->data;
5222:     mat->free_a  = PETSC_TRUE;
5223:     mat->free_ij = PETSC_TRUE;
5224:     mat->nonew   = 0;
5225:   } else if (scall == MAT_REUSE_MATRIX) {
5226:     mat = (Mat_SeqAIJ *)(*A_loc)->data;
5227:     ci  = mat->i;
5228:     cj  = mat->j;
5229:     PetscCall(MatSeqAIJGetArrayWrite(*A_loc, &cam));
5230:     for (i = 0; i < am; i++) {
5231:       /* off-diagonal portion of A */
5232:       ncols_o = bi[i + 1] - bi[i];
5233:       for (jo = 0; jo < ncols_o; jo++) {
5234:         col = cmap[*bj];
5235:         if (col >= cstart) break;
5236:         *cam++ = *ba++;
5237:         bj++;
5238:       }
5239:       /* diagonal portion of A */
5240:       ncols_d = ai[i + 1] - ai[i];
5241:       for (j = 0; j < ncols_d; j++) *cam++ = *aa++;
5242:       /* off-diagonal portion of A */
5243:       for (j = jo; j < ncols_o; j++) {
5244:         *cam++ = *ba++;
5245:         bj++;
5246:       }
5247:     }
5248:     PetscCall(MatSeqAIJRestoreArrayWrite(*A_loc, &cam));
5249:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid MatReuse %d", (int)scall);
5250:   PetscCall(MatSeqAIJRestoreArrayRead(mpimat->A, &aav));
5251:   PetscCall(MatSeqAIJRestoreArrayRead(mpimat->B, &bav));
5252:   PetscCall(PetscLogEventEnd(MAT_Getlocalmat, A, 0, 0, 0));
5253:   PetscFunctionReturn(PETSC_SUCCESS);
5254: }

5256: /*@
5257:   MatMPIAIJGetLocalMatMerge - Creates a `MATSEQAIJ` from a `MATMPIAIJ` matrix by taking all its local rows and putting them into a sequential matrix with
5258:   mlocal rows and n columns. Where n is the sum of the number of columns of the diagonal and off-diagonal part

5260:   Not Collective

5262:   Input Parameters:
5263: + A     - the matrix
5264: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5266:   Output Parameters:
5267: + glob  - sequential `IS` with global indices associated with the columns of the local sequential matrix generated (can be `NULL`)
5268: - A_loc - the local sequential matrix generated

5270:   Level: developer

5272:   Note:
5273:   This is different from `MatMPIAIJGetLocalMat()` since the first columns in the returning matrix are those associated with the diagonal
5274:   part, then those associated with the off-diagonal part (in its local ordering)

5276: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMat()`, `MatMPIAIJGetLocalMatCondensed()`
5277: @*/
5278: PetscErrorCode MatMPIAIJGetLocalMatMerge(Mat A, MatReuse scall, IS *glob, Mat *A_loc)
5279: {
5280:   Mat             Ao, Ad;
5281:   const PetscInt *cmap;
5282:   PetscMPIInt     size;
5283:   PetscErrorCode (*f)(Mat, MatReuse, IS *, Mat *);

5285:   PetscFunctionBegin;
5286:   PetscCall(MatMPIAIJGetSeqAIJ(A, &Ad, &Ao, &cmap));
5287:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)A), &size));
5288:   if (size == 1) {
5289:     if (scall == MAT_INITIAL_MATRIX) {
5290:       PetscCall(PetscObjectReference((PetscObject)Ad));
5291:       *A_loc = Ad;
5292:     } else if (scall == MAT_REUSE_MATRIX) {
5293:       PetscCall(MatCopy(Ad, *A_loc, SAME_NONZERO_PATTERN));
5294:     }
5295:     if (glob) PetscCall(ISCreateStride(PetscObjectComm((PetscObject)Ad), Ad->cmap->n, Ad->cmap->rstart, 1, glob));
5296:     PetscFunctionReturn(PETSC_SUCCESS);
5297:   }
5298:   PetscCall(PetscObjectQueryFunction((PetscObject)A, "MatMPIAIJGetLocalMatMerge_C", &f));
5299:   PetscCall(PetscLogEventBegin(MAT_Getlocalmat, A, 0, 0, 0));
5300:   if (f) {
5301:     PetscCall((*f)(A, scall, glob, A_loc));
5302:   } else {
5303:     Mat_SeqAIJ        *a = (Mat_SeqAIJ *)Ad->data;
5304:     Mat_SeqAIJ        *b = (Mat_SeqAIJ *)Ao->data;
5305:     Mat_SeqAIJ        *c;
5306:     PetscInt          *ai = a->i, *aj = a->j;
5307:     PetscInt          *bi = b->i, *bj = b->j;
5308:     PetscInt          *ci, *cj;
5309:     const PetscScalar *aa, *ba;
5310:     PetscScalar       *ca;
5311:     PetscInt           i, j, am, dn, on;

5313:     PetscCall(MatGetLocalSize(Ad, &am, &dn));
5314:     PetscCall(MatGetLocalSize(Ao, NULL, &on));
5315:     PetscCall(MatSeqAIJGetArrayRead(Ad, &aa));
5316:     PetscCall(MatSeqAIJGetArrayRead(Ao, &ba));
5317:     if (scall == MAT_INITIAL_MATRIX) {
5318:       PetscInt k;
5319:       PetscCall(PetscMalloc1(1 + am, &ci));
5320:       PetscCall(PetscMalloc1(ai[am] + bi[am], &cj));
5321:       PetscCall(PetscMalloc1(ai[am] + bi[am], &ca));
5322:       ci[0] = 0;
5323:       for (i = 0, k = 0; i < am; i++) {
5324:         const PetscInt ncols_o = bi[i + 1] - bi[i];
5325:         const PetscInt ncols_d = ai[i + 1] - ai[i];
5326:         ci[i + 1]              = ci[i] + ncols_o + ncols_d;
5327:         /* diagonal portion of A */
5328:         for (j = 0; j < ncols_d; j++, k++) {
5329:           cj[k] = *aj++;
5330:           ca[k] = *aa++;
5331:         }
5332:         /* off-diagonal portion of A */
5333:         for (j = 0; j < ncols_o; j++, k++) {
5334:           cj[k] = dn + *bj++;
5335:           ca[k] = *ba++;
5336:         }
5337:       }
5338:       /* put together the new matrix */
5339:       PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, am, dn + on, ci, cj, ca, A_loc));
5340:       /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5341:       /* Since these are PETSc arrays, change flags to free them as necessary. */
5342:       c          = (Mat_SeqAIJ *)(*A_loc)->data;
5343:       c->free_a  = PETSC_TRUE;
5344:       c->free_ij = PETSC_TRUE;
5345:       c->nonew   = 0;
5346:       PetscCall(MatSetType(*A_loc, ((PetscObject)Ad)->type_name));
5347:     } else if (scall == MAT_REUSE_MATRIX) {
5348:       PetscCall(MatSeqAIJGetArrayWrite(*A_loc, &ca));
5349:       for (i = 0; i < am; i++) {
5350:         const PetscInt ncols_d = ai[i + 1] - ai[i];
5351:         const PetscInt ncols_o = bi[i + 1] - bi[i];
5352:         /* diagonal portion of A */
5353:         for (j = 0; j < ncols_d; j++) *ca++ = *aa++;
5354:         /* off-diagonal portion of A */
5355:         for (j = 0; j < ncols_o; j++) *ca++ = *ba++;
5356:       }
5357:       PetscCall(MatSeqAIJRestoreArrayWrite(*A_loc, &ca));
5358:     } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid MatReuse %d", (int)scall);
5359:     PetscCall(MatSeqAIJRestoreArrayRead(Ad, &aa));
5360:     PetscCall(MatSeqAIJRestoreArrayRead(Ao, &aa));
5361:     if (glob) {
5362:       PetscInt cst, *gidx;

5364:       PetscCall(MatGetOwnershipRangeColumn(A, &cst, NULL));
5365:       PetscCall(PetscMalloc1(dn + on, &gidx));
5366:       for (i = 0; i < dn; i++) gidx[i] = cst + i;
5367:       for (i = 0; i < on; i++) gidx[i + dn] = cmap[i];
5368:       PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)Ad), dn + on, gidx, PETSC_OWN_POINTER, glob));
5369:     }
5370:   }
5371:   PetscCall(PetscLogEventEnd(MAT_Getlocalmat, A, 0, 0, 0));
5372:   PetscFunctionReturn(PETSC_SUCCESS);
5373: }

5375: /*@C
5376:   MatMPIAIJGetLocalMatCondensed - Creates a `MATSEQAIJ` matrix from an `MATMPIAIJ` matrix by taking all its local rows and NON-ZERO columns

5378:   Not Collective

5380:   Input Parameters:
5381: + A     - the matrix
5382: . scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`
5383: . row   - index set of rows to extract (or `NULL`)
5384: - col   - index set of columns to extract (or `NULL`)

5386:   Output Parameter:
5387: . A_loc - the local sequential matrix generated

5389:   Level: developer

5391: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMat()`
5392: @*/
5393: PetscErrorCode MatMPIAIJGetLocalMatCondensed(Mat A, MatReuse scall, IS *row, IS *col, Mat *A_loc)
5394: {
5395:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
5396:   PetscInt    i, start, end, ncols, nzA, nzB, *cmap, imark, *idx;
5397:   IS          isrowa, iscola;
5398:   Mat        *aloc;
5399:   PetscBool   match;

5401:   PetscFunctionBegin;
5402:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATMPIAIJ, &match));
5403:   PetscCheck(match, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Requires MATMPIAIJ matrix as input");
5404:   PetscCall(PetscLogEventBegin(MAT_Getlocalmatcondensed, A, 0, 0, 0));
5405:   if (!row) {
5406:     start = A->rmap->rstart;
5407:     end   = A->rmap->rend;
5408:     PetscCall(ISCreateStride(PETSC_COMM_SELF, end - start, start, 1, &isrowa));
5409:   } else {
5410:     isrowa = *row;
5411:   }
5412:   if (!col) {
5413:     start = A->cmap->rstart;
5414:     cmap  = a->garray;
5415:     nzA   = a->A->cmap->n;
5416:     nzB   = a->B->cmap->n;
5417:     PetscCall(PetscMalloc1(nzA + nzB, &idx));
5418:     ncols = 0;
5419:     for (i = 0; i < nzB; i++) {
5420:       if (cmap[i] < start) idx[ncols++] = cmap[i];
5421:       else break;
5422:     }
5423:     imark = i;
5424:     for (i = 0; i < nzA; i++) idx[ncols++] = start + i;
5425:     for (i = imark; i < nzB; i++) idx[ncols++] = cmap[i];
5426:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, &iscola));
5427:   } else {
5428:     iscola = *col;
5429:   }
5430:   if (scall != MAT_INITIAL_MATRIX) {
5431:     PetscCall(PetscMalloc1(1, &aloc));
5432:     aloc[0] = *A_loc;
5433:   }
5434:   PetscCall(MatCreateSubMatrices(A, 1, &isrowa, &iscola, scall, &aloc));
5435:   if (!col) { /* attach global id of condensed columns */
5436:     PetscCall(PetscObjectCompose((PetscObject)aloc[0], "_petsc_GetLocalMatCondensed_iscol", (PetscObject)iscola));
5437:   }
5438:   *A_loc = aloc[0];
5439:   PetscCall(PetscFree(aloc));
5440:   if (!row) PetscCall(ISDestroy(&isrowa));
5441:   if (!col) PetscCall(ISDestroy(&iscola));
5442:   PetscCall(PetscLogEventEnd(MAT_Getlocalmatcondensed, A, 0, 0, 0));
5443:   PetscFunctionReturn(PETSC_SUCCESS);
5444: }

5446: /*
5447:  * Create a sequential AIJ matrix based on row indices. a whole column is extracted once a row is matched.
5448:  * Row could be local or remote.The routine is designed to be scalable in memory so that nothing is based
5449:  * on a global size.
5450:  * */
5451: static PetscErrorCode MatCreateSeqSubMatrixWithRows_Private(Mat P, IS rows, Mat *P_oth)
5452: {
5453:   Mat_MPIAIJ            *p  = (Mat_MPIAIJ *)P->data;
5454:   Mat_SeqAIJ            *pd = (Mat_SeqAIJ *)(p->A)->data, *po = (Mat_SeqAIJ *)(p->B)->data, *p_oth;
5455:   PetscInt               plocalsize, nrows, *ilocal, *oilocal, i, lidx, *nrcols, *nlcols, ncol;
5456:   PetscMPIInt            owner;
5457:   PetscSFNode           *iremote, *oiremote;
5458:   const PetscInt        *lrowindices;
5459:   PetscSF                sf, osf;
5460:   PetscInt               pcstart, *roffsets, *loffsets, *pnnz, j;
5461:   PetscInt               ontotalcols, dntotalcols, ntotalcols, nout;
5462:   MPI_Comm               comm;
5463:   ISLocalToGlobalMapping mapping;
5464:   const PetscScalar     *pd_a, *po_a;

5466:   PetscFunctionBegin;
5467:   PetscCall(PetscObjectGetComm((PetscObject)P, &comm));
5468:   /* plocalsize is the number of roots
5469:    * nrows is the number of leaves
5470:    * */
5471:   PetscCall(MatGetLocalSize(P, &plocalsize, NULL));
5472:   PetscCall(ISGetLocalSize(rows, &nrows));
5473:   PetscCall(PetscCalloc1(nrows, &iremote));
5474:   PetscCall(ISGetIndices(rows, &lrowindices));
5475:   for (i = 0; i < nrows; i++) {
5476:     /* Find a remote index and an owner for a row
5477:      * The row could be local or remote
5478:      * */
5479:     owner = 0;
5480:     lidx  = 0;
5481:     PetscCall(PetscLayoutFindOwnerIndex(P->rmap, lrowindices[i], &owner, &lidx));
5482:     iremote[i].index = lidx;
5483:     iremote[i].rank  = owner;
5484:   }
5485:   /* Create SF to communicate how many nonzero columns for each row */
5486:   PetscCall(PetscSFCreate(comm, &sf));
5487:   /* SF will figure out the number of nonzero columns for each row, and their
5488:    * offsets
5489:    * */
5490:   PetscCall(PetscSFSetGraph(sf, plocalsize, nrows, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
5491:   PetscCall(PetscSFSetFromOptions(sf));
5492:   PetscCall(PetscSFSetUp(sf));

5494:   PetscCall(PetscCalloc1(2 * (plocalsize + 1), &roffsets));
5495:   PetscCall(PetscCalloc1(2 * plocalsize, &nrcols));
5496:   PetscCall(PetscCalloc1(nrows, &pnnz));
5497:   roffsets[0] = 0;
5498:   roffsets[1] = 0;
5499:   for (i = 0; i < plocalsize; i++) {
5500:     /* diagonal */
5501:     nrcols[i * 2 + 0] = pd->i[i + 1] - pd->i[i];
5502:     /* off-diagonal */
5503:     nrcols[i * 2 + 1] = po->i[i + 1] - po->i[i];
5504:     /* compute offsets so that we relative location for each row */
5505:     roffsets[(i + 1) * 2 + 0] = roffsets[i * 2 + 0] + nrcols[i * 2 + 0];
5506:     roffsets[(i + 1) * 2 + 1] = roffsets[i * 2 + 1] + nrcols[i * 2 + 1];
5507:   }
5508:   PetscCall(PetscCalloc1(2 * nrows, &nlcols));
5509:   PetscCall(PetscCalloc1(2 * nrows, &loffsets));
5510:   /* 'r' means root, and 'l' means leaf */
5511:   PetscCall(PetscSFBcastBegin(sf, MPIU_2INT, nrcols, nlcols, MPI_REPLACE));
5512:   PetscCall(PetscSFBcastBegin(sf, MPIU_2INT, roffsets, loffsets, MPI_REPLACE));
5513:   PetscCall(PetscSFBcastEnd(sf, MPIU_2INT, nrcols, nlcols, MPI_REPLACE));
5514:   PetscCall(PetscSFBcastEnd(sf, MPIU_2INT, roffsets, loffsets, MPI_REPLACE));
5515:   PetscCall(PetscSFDestroy(&sf));
5516:   PetscCall(PetscFree(roffsets));
5517:   PetscCall(PetscFree(nrcols));
5518:   dntotalcols = 0;
5519:   ontotalcols = 0;
5520:   ncol        = 0;
5521:   for (i = 0; i < nrows; i++) {
5522:     pnnz[i] = nlcols[i * 2 + 0] + nlcols[i * 2 + 1];
5523:     ncol    = PetscMax(pnnz[i], ncol);
5524:     /* diagonal */
5525:     dntotalcols += nlcols[i * 2 + 0];
5526:     /* off-diagonal */
5527:     ontotalcols += nlcols[i * 2 + 1];
5528:   }
5529:   /* We do not need to figure the right number of columns
5530:    * since all the calculations will be done by going through the raw data
5531:    * */
5532:   PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, nrows, ncol, 0, pnnz, P_oth));
5533:   PetscCall(MatSetUp(*P_oth));
5534:   PetscCall(PetscFree(pnnz));
5535:   p_oth = (Mat_SeqAIJ *)(*P_oth)->data;
5536:   /* diagonal */
5537:   PetscCall(PetscCalloc1(dntotalcols, &iremote));
5538:   /* off-diagonal */
5539:   PetscCall(PetscCalloc1(ontotalcols, &oiremote));
5540:   /* diagonal */
5541:   PetscCall(PetscCalloc1(dntotalcols, &ilocal));
5542:   /* off-diagonal */
5543:   PetscCall(PetscCalloc1(ontotalcols, &oilocal));
5544:   dntotalcols = 0;
5545:   ontotalcols = 0;
5546:   ntotalcols  = 0;
5547:   for (i = 0; i < nrows; i++) {
5548:     owner = 0;
5549:     PetscCall(PetscLayoutFindOwnerIndex(P->rmap, lrowindices[i], &owner, NULL));
5550:     /* Set iremote for diag matrix */
5551:     for (j = 0; j < nlcols[i * 2 + 0]; j++) {
5552:       iremote[dntotalcols].index = loffsets[i * 2 + 0] + j;
5553:       iremote[dntotalcols].rank  = owner;
5554:       /* P_oth is seqAIJ so that ilocal need to point to the first part of memory */
5555:       ilocal[dntotalcols++] = ntotalcols++;
5556:     }
5557:     /* off-diagonal */
5558:     for (j = 0; j < nlcols[i * 2 + 1]; j++) {
5559:       oiremote[ontotalcols].index = loffsets[i * 2 + 1] + j;
5560:       oiremote[ontotalcols].rank  = owner;
5561:       oilocal[ontotalcols++]      = ntotalcols++;
5562:     }
5563:   }
5564:   PetscCall(ISRestoreIndices(rows, &lrowindices));
5565:   PetscCall(PetscFree(loffsets));
5566:   PetscCall(PetscFree(nlcols));
5567:   PetscCall(PetscSFCreate(comm, &sf));
5568:   /* P serves as roots and P_oth is leaves
5569:    * Diag matrix
5570:    * */
5571:   PetscCall(PetscSFSetGraph(sf, pd->i[plocalsize], dntotalcols, ilocal, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
5572:   PetscCall(PetscSFSetFromOptions(sf));
5573:   PetscCall(PetscSFSetUp(sf));

5575:   PetscCall(PetscSFCreate(comm, &osf));
5576:   /* off-diagonal */
5577:   PetscCall(PetscSFSetGraph(osf, po->i[plocalsize], ontotalcols, oilocal, PETSC_OWN_POINTER, oiremote, PETSC_OWN_POINTER));
5578:   PetscCall(PetscSFSetFromOptions(osf));
5579:   PetscCall(PetscSFSetUp(osf));
5580:   PetscCall(MatSeqAIJGetArrayRead(p->A, &pd_a));
5581:   PetscCall(MatSeqAIJGetArrayRead(p->B, &po_a));
5582:   /* operate on the matrix internal data to save memory */
5583:   PetscCall(PetscSFBcastBegin(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5584:   PetscCall(PetscSFBcastBegin(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5585:   PetscCall(MatGetOwnershipRangeColumn(P, &pcstart, NULL));
5586:   /* Convert to global indices for diag matrix */
5587:   for (i = 0; i < pd->i[plocalsize]; i++) pd->j[i] += pcstart;
5588:   PetscCall(PetscSFBcastBegin(sf, MPIU_INT, pd->j, p_oth->j, MPI_REPLACE));
5589:   /* We want P_oth store global indices */
5590:   PetscCall(ISLocalToGlobalMappingCreate(comm, 1, p->B->cmap->n, p->garray, PETSC_COPY_VALUES, &mapping));
5591:   /* Use memory scalable approach */
5592:   PetscCall(ISLocalToGlobalMappingSetType(mapping, ISLOCALTOGLOBALMAPPINGHASH));
5593:   PetscCall(ISLocalToGlobalMappingApply(mapping, po->i[plocalsize], po->j, po->j));
5594:   PetscCall(PetscSFBcastBegin(osf, MPIU_INT, po->j, p_oth->j, MPI_REPLACE));
5595:   PetscCall(PetscSFBcastEnd(sf, MPIU_INT, pd->j, p_oth->j, MPI_REPLACE));
5596:   /* Convert back to local indices */
5597:   for (i = 0; i < pd->i[plocalsize]; i++) pd->j[i] -= pcstart;
5598:   PetscCall(PetscSFBcastEnd(osf, MPIU_INT, po->j, p_oth->j, MPI_REPLACE));
5599:   nout = 0;
5600:   PetscCall(ISGlobalToLocalMappingApply(mapping, IS_GTOLM_DROP, po->i[plocalsize], po->j, &nout, po->j));
5601:   PetscCheck(nout == po->i[plocalsize], comm, PETSC_ERR_ARG_INCOMP, "n %" PetscInt_FMT " does not equal to nout %" PetscInt_FMT " ", po->i[plocalsize], nout);
5602:   PetscCall(ISLocalToGlobalMappingDestroy(&mapping));
5603:   /* Exchange values */
5604:   PetscCall(PetscSFBcastEnd(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5605:   PetscCall(PetscSFBcastEnd(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5606:   PetscCall(MatSeqAIJRestoreArrayRead(p->A, &pd_a));
5607:   PetscCall(MatSeqAIJRestoreArrayRead(p->B, &po_a));
5608:   /* Stop PETSc from shrinking memory */
5609:   for (i = 0; i < nrows; i++) p_oth->ilen[i] = p_oth->imax[i];
5610:   PetscCall(MatAssemblyBegin(*P_oth, MAT_FINAL_ASSEMBLY));
5611:   PetscCall(MatAssemblyEnd(*P_oth, MAT_FINAL_ASSEMBLY));
5612:   /* Attach PetscSF objects to P_oth so that we can reuse it later */
5613:   PetscCall(PetscObjectCompose((PetscObject)*P_oth, "diagsf", (PetscObject)sf));
5614:   PetscCall(PetscObjectCompose((PetscObject)*P_oth, "offdiagsf", (PetscObject)osf));
5615:   PetscCall(PetscSFDestroy(&sf));
5616:   PetscCall(PetscSFDestroy(&osf));
5617:   PetscFunctionReturn(PETSC_SUCCESS);
5618: }

5620: /*
5621:  * Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns of local A
5622:  * This supports MPIAIJ and MAIJ
5623:  * */
5624: PetscErrorCode MatGetBrowsOfAcols_MPIXAIJ(Mat A, Mat P, PetscInt dof, MatReuse reuse, Mat *P_oth)
5625: {
5626:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data, *p = (Mat_MPIAIJ *)P->data;
5627:   Mat_SeqAIJ *p_oth;
5628:   IS          rows, map;
5629:   PetscHMapI  hamp;
5630:   PetscInt    i, htsize, *rowindices, off, *mapping, key, count;
5631:   MPI_Comm    comm;
5632:   PetscSF     sf, osf;
5633:   PetscBool   has;

5635:   PetscFunctionBegin;
5636:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
5637:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAocols, A, P, 0, 0));
5638:   /* If it is the first time, create an index set of off-diag nonzero columns of A,
5639:    *  and then create a submatrix (that often is an overlapping matrix)
5640:    * */
5641:   if (reuse == MAT_INITIAL_MATRIX) {
5642:     /* Use a hash table to figure out unique keys */
5643:     PetscCall(PetscHMapICreateWithSize(a->B->cmap->n, &hamp));
5644:     PetscCall(PetscCalloc1(a->B->cmap->n, &mapping));
5645:     count = 0;
5646:     /* Assume that  a->g is sorted, otherwise the following does not make sense */
5647:     for (i = 0; i < a->B->cmap->n; i++) {
5648:       key = a->garray[i] / dof;
5649:       PetscCall(PetscHMapIHas(hamp, key, &has));
5650:       if (!has) {
5651:         mapping[i] = count;
5652:         PetscCall(PetscHMapISet(hamp, key, count++));
5653:       } else {
5654:         /* Current 'i' has the same value the previous step */
5655:         mapping[i] = count - 1;
5656:       }
5657:     }
5658:     PetscCall(ISCreateGeneral(comm, a->B->cmap->n, mapping, PETSC_OWN_POINTER, &map));
5659:     PetscCall(PetscHMapIGetSize(hamp, &htsize));
5660:     PetscCheck(htsize == count, comm, PETSC_ERR_ARG_INCOMP, " Size of hash map %" PetscInt_FMT " is inconsistent with count %" PetscInt_FMT, htsize, count);
5661:     PetscCall(PetscCalloc1(htsize, &rowindices));
5662:     off = 0;
5663:     PetscCall(PetscHMapIGetKeys(hamp, &off, rowindices));
5664:     PetscCall(PetscHMapIDestroy(&hamp));
5665:     PetscCall(PetscSortInt(htsize, rowindices));
5666:     PetscCall(ISCreateGeneral(comm, htsize, rowindices, PETSC_OWN_POINTER, &rows));
5667:     /* In case, the matrix was already created but users want to recreate the matrix */
5668:     PetscCall(MatDestroy(P_oth));
5669:     PetscCall(MatCreateSeqSubMatrixWithRows_Private(P, rows, P_oth));
5670:     PetscCall(PetscObjectCompose((PetscObject)*P_oth, "aoffdiagtopothmapping", (PetscObject)map));
5671:     PetscCall(ISDestroy(&map));
5672:     PetscCall(ISDestroy(&rows));
5673:   } else if (reuse == MAT_REUSE_MATRIX) {
5674:     /* If matrix was already created, we simply update values using SF objects
5675:      * that as attached to the matrix earlier.
5676:      */
5677:     const PetscScalar *pd_a, *po_a;

5679:     PetscCall(PetscObjectQuery((PetscObject)*P_oth, "diagsf", (PetscObject *)&sf));
5680:     PetscCall(PetscObjectQuery((PetscObject)*P_oth, "offdiagsf", (PetscObject *)&osf));
5681:     PetscCheck(sf && osf, comm, PETSC_ERR_ARG_NULL, "Matrix is not initialized yet");
5682:     p_oth = (Mat_SeqAIJ *)(*P_oth)->data;
5683:     /* Update values in place */
5684:     PetscCall(MatSeqAIJGetArrayRead(p->A, &pd_a));
5685:     PetscCall(MatSeqAIJGetArrayRead(p->B, &po_a));
5686:     PetscCall(PetscSFBcastBegin(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5687:     PetscCall(PetscSFBcastBegin(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5688:     PetscCall(PetscSFBcastEnd(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5689:     PetscCall(PetscSFBcastEnd(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5690:     PetscCall(MatSeqAIJRestoreArrayRead(p->A, &pd_a));
5691:     PetscCall(MatSeqAIJRestoreArrayRead(p->B, &po_a));
5692:   } else SETERRQ(comm, PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown reuse type");
5693:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAocols, A, P, 0, 0));
5694:   PetscFunctionReturn(PETSC_SUCCESS);
5695: }

5697: /*@C
5698:   MatGetBrowsOfAcols - Returns `IS` that contain rows of `B` that equal to nonzero columns of local `A`

5700:   Collective

5702:   Input Parameters:
5703: + A     - the first matrix in `MATMPIAIJ` format
5704: . B     - the second matrix in `MATMPIAIJ` format
5705: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5707:   Output Parameters:
5708: + rowb  - On input index sets of rows of B to extract (or `NULL`), modified on output
5709: . colb  - On input index sets of columns of B to extract (or `NULL`), modified on output
5710: - B_seq - the sequential matrix generated

5712:   Level: developer

5714: .seealso: `Mat`, `MATMPIAIJ`, `IS`, `MatReuse`
5715: @*/
5716: PetscErrorCode MatGetBrowsOfAcols(Mat A, Mat B, MatReuse scall, IS *rowb, IS *colb, Mat *B_seq)
5717: {
5718:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
5719:   PetscInt   *idx, i, start, ncols, nzA, nzB, *cmap, imark;
5720:   IS          isrowb, iscolb;
5721:   Mat        *bseq = NULL;

5723:   PetscFunctionBegin;
5724:   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 ")",
5725:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
5726:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAcols, A, B, 0, 0));

5728:   if (scall == MAT_INITIAL_MATRIX) {
5729:     start = A->cmap->rstart;
5730:     cmap  = a->garray;
5731:     nzA   = a->A->cmap->n;
5732:     nzB   = a->B->cmap->n;
5733:     PetscCall(PetscMalloc1(nzA + nzB, &idx));
5734:     ncols = 0;
5735:     for (i = 0; i < nzB; i++) { /* row < local row index */
5736:       if (cmap[i] < start) idx[ncols++] = cmap[i];
5737:       else break;
5738:     }
5739:     imark = i;
5740:     for (i = 0; i < nzA; i++) idx[ncols++] = start + i;   /* local rows */
5741:     for (i = imark; i < nzB; i++) idx[ncols++] = cmap[i]; /* row > local row index */
5742:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, &isrowb));
5743:     PetscCall(ISCreateStride(PETSC_COMM_SELF, B->cmap->N, 0, 1, &iscolb));
5744:   } else {
5745:     PetscCheck(rowb && colb, PETSC_COMM_SELF, PETSC_ERR_SUP, "IS rowb and colb must be provided for MAT_REUSE_MATRIX");
5746:     isrowb = *rowb;
5747:     iscolb = *colb;
5748:     PetscCall(PetscMalloc1(1, &bseq));
5749:     bseq[0] = *B_seq;
5750:   }
5751:   PetscCall(MatCreateSubMatrices(B, 1, &isrowb, &iscolb, scall, &bseq));
5752:   *B_seq = bseq[0];
5753:   PetscCall(PetscFree(bseq));
5754:   if (!rowb) {
5755:     PetscCall(ISDestroy(&isrowb));
5756:   } else {
5757:     *rowb = isrowb;
5758:   }
5759:   if (!colb) {
5760:     PetscCall(ISDestroy(&iscolb));
5761:   } else {
5762:     *colb = iscolb;
5763:   }
5764:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAcols, A, B, 0, 0));
5765:   PetscFunctionReturn(PETSC_SUCCESS);
5766: }

5768: /*
5769:     MatGetBrowsOfAoCols_MPIAIJ - Creates a `MATSEQAIJ` matrix by taking rows of B that equal to nonzero columns
5770:     of the OFF-DIAGONAL portion of local A

5772:     Collective

5774:    Input Parameters:
5775: +    A,B - the matrices in `MATMPIAIJ` format
5776: -    scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5778:    Output Parameter:
5779: +    startsj_s - starting point in B's sending j-arrays, saved for MAT_REUSE (or NULL)
5780: .    startsj_r - starting point in B's receiving j-arrays, saved for MAT_REUSE (or NULL)
5781: .    bufa_ptr - array for sending matrix values, saved for MAT_REUSE (or NULL)
5782: -    B_oth - the sequential matrix generated with size aBn=a->B->cmap->n by B->cmap->N

5784:     Developer Note:
5785:     This directly accesses information inside the VecScatter associated with the matrix-vector product
5786:      for this matrix. This is not desirable..

5788:     Level: developer

5790: */
5791: PetscErrorCode MatGetBrowsOfAoCols_MPIAIJ(Mat A, Mat B, MatReuse scall, PetscInt **startsj_s, PetscInt **startsj_r, MatScalar **bufa_ptr, Mat *B_oth)
5792: {
5793:   Mat_MPIAIJ        *a = (Mat_MPIAIJ *)A->data;
5794:   Mat_SeqAIJ        *b_oth;
5795:   VecScatter         ctx;
5796:   MPI_Comm           comm;
5797:   const PetscMPIInt *rprocs, *sprocs;
5798:   const PetscInt    *srow, *rstarts, *sstarts;
5799:   PetscInt          *rowlen, *bufj, *bufJ, ncols = 0, aBn = a->B->cmap->n, row, *b_othi, *b_othj, *rvalues = NULL, *svalues = NULL, *cols, sbs, rbs;
5800:   PetscInt           i, j, k = 0, l, ll, nrecvs, nsends, nrows, *rstartsj = NULL, *sstartsj, len;
5801:   PetscScalar       *b_otha, *bufa, *bufA, *vals = NULL;
5802:   MPI_Request       *reqs = NULL, *rwaits = NULL, *swaits = NULL;
5803:   PetscMPIInt        size, tag, rank, nreqs;

5805:   PetscFunctionBegin;
5806:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
5807:   PetscCallMPI(MPI_Comm_size(comm, &size));

5809:   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 ")",
5810:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
5811:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAocols, A, B, 0, 0));
5812:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

5814:   if (size == 1) {
5815:     startsj_s = NULL;
5816:     bufa_ptr  = NULL;
5817:     *B_oth    = NULL;
5818:     PetscFunctionReturn(PETSC_SUCCESS);
5819:   }

5821:   ctx = a->Mvctx;
5822:   tag = ((PetscObject)ctx)->tag;

5824:   PetscCall(VecScatterGetRemote_Private(ctx, PETSC_TRUE /*send*/, &nsends, &sstarts, &srow, &sprocs, &sbs));
5825:   /* rprocs[] must be ordered so that indices received from them are ordered in rvalues[], which is key to algorithms used in this subroutine */
5826:   PetscCall(VecScatterGetRemoteOrdered_Private(ctx, PETSC_FALSE /*recv*/, &nrecvs, &rstarts, NULL /*indices not needed*/, &rprocs, &rbs));
5827:   PetscCall(PetscMPIIntCast(nsends + nrecvs, &nreqs));
5828:   PetscCall(PetscMalloc1(nreqs, &reqs));
5829:   rwaits = reqs;
5830:   swaits = reqs + nrecvs;

5832:   if (!startsj_s || !bufa_ptr) scall = MAT_INITIAL_MATRIX;
5833:   if (scall == MAT_INITIAL_MATRIX) {
5834:     /* i-array */
5835:     /*  post receives */
5836:     if (nrecvs) PetscCall(PetscMalloc1(rbs * (rstarts[nrecvs] - rstarts[0]), &rvalues)); /* rstarts can be NULL when nrecvs=0 */
5837:     for (i = 0; i < nrecvs; i++) {
5838:       rowlen = rvalues + rstarts[i] * rbs;
5839:       nrows  = (rstarts[i + 1] - rstarts[i]) * rbs; /* num of indices to be received */
5840:       PetscCallMPI(MPI_Irecv(rowlen, nrows, MPIU_INT, rprocs[i], tag, comm, rwaits + i));
5841:     }

5843:     /* pack the outgoing message */
5844:     PetscCall(PetscMalloc2(nsends + 1, &sstartsj, nrecvs + 1, &rstartsj));

5846:     sstartsj[0] = 0;
5847:     rstartsj[0] = 0;
5848:     len         = 0; /* total length of j or a array to be sent */
5849:     if (nsends) {
5850:       k = sstarts[0]; /* ATTENTION: sstarts[0] and rstarts[0] are not necessarily zero */
5851:       PetscCall(PetscMalloc1(sbs * (sstarts[nsends] - sstarts[0]), &svalues));
5852:     }
5853:     for (i = 0; i < nsends; i++) {
5854:       rowlen = svalues + (sstarts[i] - sstarts[0]) * sbs;
5855:       nrows  = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5856:       for (j = 0; j < nrows; j++) {
5857:         row = srow[k] + B->rmap->range[rank]; /* global row idx */
5858:         for (l = 0; l < sbs; l++) {
5859:           PetscCall(MatGetRow_MPIAIJ(B, row + l, &ncols, NULL, NULL)); /* rowlength */

5861:           rowlen[j * sbs + l] = ncols;

5863:           len += ncols;
5864:           PetscCall(MatRestoreRow_MPIAIJ(B, row + l, &ncols, NULL, NULL));
5865:         }
5866:         k++;
5867:       }
5868:       PetscCallMPI(MPI_Isend(rowlen, nrows * sbs, MPIU_INT, sprocs[i], tag, comm, swaits + i));

5870:       sstartsj[i + 1] = len; /* starting point of (i+1)-th outgoing msg in bufj and bufa */
5871:     }
5872:     /* recvs and sends of i-array are completed */
5873:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5874:     PetscCall(PetscFree(svalues));

5876:     /* allocate buffers for sending j and a arrays */
5877:     PetscCall(PetscMalloc1(len + 1, &bufj));
5878:     PetscCall(PetscMalloc1(len + 1, &bufa));

5880:     /* create i-array of B_oth */
5881:     PetscCall(PetscMalloc1(aBn + 2, &b_othi));

5883:     b_othi[0] = 0;
5884:     len       = 0; /* total length of j or a array to be received */
5885:     k         = 0;
5886:     for (i = 0; i < nrecvs; i++) {
5887:       rowlen = rvalues + (rstarts[i] - rstarts[0]) * rbs;
5888:       nrows  = (rstarts[i + 1] - rstarts[i]) * rbs; /* num of rows to be received */
5889:       for (j = 0; j < nrows; j++) {
5890:         b_othi[k + 1] = b_othi[k] + rowlen[j];
5891:         PetscCall(PetscIntSumError(rowlen[j], len, &len));
5892:         k++;
5893:       }
5894:       rstartsj[i + 1] = len; /* starting point of (i+1)-th incoming msg in bufj and bufa */
5895:     }
5896:     PetscCall(PetscFree(rvalues));

5898:     /* allocate space for j and a arrays of B_oth */
5899:     PetscCall(PetscMalloc1(b_othi[aBn] + 1, &b_othj));
5900:     PetscCall(PetscMalloc1(b_othi[aBn] + 1, &b_otha));

5902:     /* j-array */
5903:     /*  post receives of j-array */
5904:     for (i = 0; i < nrecvs; i++) {
5905:       nrows = rstartsj[i + 1] - rstartsj[i]; /* length of the msg received */
5906:       PetscCallMPI(MPI_Irecv(b_othj + rstartsj[i], nrows, MPIU_INT, rprocs[i], tag, comm, rwaits + i));
5907:     }

5909:     /* pack the outgoing message j-array */
5910:     if (nsends) k = sstarts[0];
5911:     for (i = 0; i < nsends; i++) {
5912:       nrows = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5913:       bufJ  = bufj + sstartsj[i];
5914:       for (j = 0; j < nrows; j++) {
5915:         row = srow[k++] + B->rmap->range[rank]; /* global row idx */
5916:         for (ll = 0; ll < sbs; ll++) {
5917:           PetscCall(MatGetRow_MPIAIJ(B, row + ll, &ncols, &cols, NULL));
5918:           for (l = 0; l < ncols; l++) *bufJ++ = cols[l];
5919:           PetscCall(MatRestoreRow_MPIAIJ(B, row + ll, &ncols, &cols, NULL));
5920:         }
5921:       }
5922:       PetscCallMPI(MPI_Isend(bufj + sstartsj[i], sstartsj[i + 1] - sstartsj[i], MPIU_INT, sprocs[i], tag, comm, swaits + i));
5923:     }

5925:     /* recvs and sends of j-array are completed */
5926:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5927:   } else if (scall == MAT_REUSE_MATRIX) {
5928:     sstartsj = *startsj_s;
5929:     rstartsj = *startsj_r;
5930:     bufa     = *bufa_ptr;
5931:     b_oth    = (Mat_SeqAIJ *)(*B_oth)->data;
5932:     PetscCall(MatSeqAIJGetArrayWrite(*B_oth, &b_otha));
5933:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Matrix P does not possess an object container");

5935:   /* a-array */
5936:   /*  post receives of a-array */
5937:   for (i = 0; i < nrecvs; i++) {
5938:     nrows = rstartsj[i + 1] - rstartsj[i]; /* length of the msg received */
5939:     PetscCallMPI(MPI_Irecv(b_otha + rstartsj[i], nrows, MPIU_SCALAR, rprocs[i], tag, comm, rwaits + i));
5940:   }

5942:   /* pack the outgoing message a-array */
5943:   if (nsends) k = sstarts[0];
5944:   for (i = 0; i < nsends; i++) {
5945:     nrows = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5946:     bufA  = bufa + sstartsj[i];
5947:     for (j = 0; j < nrows; j++) {
5948:       row = srow[k++] + B->rmap->range[rank]; /* global row idx */
5949:       for (ll = 0; ll < sbs; ll++) {
5950:         PetscCall(MatGetRow_MPIAIJ(B, row + ll, &ncols, NULL, &vals));
5951:         for (l = 0; l < ncols; l++) *bufA++ = vals[l];
5952:         PetscCall(MatRestoreRow_MPIAIJ(B, row + ll, &ncols, NULL, &vals));
5953:       }
5954:     }
5955:     PetscCallMPI(MPI_Isend(bufa + sstartsj[i], sstartsj[i + 1] - sstartsj[i], MPIU_SCALAR, sprocs[i], tag, comm, swaits + i));
5956:   }
5957:   /* recvs and sends of a-array are completed */
5958:   if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5959:   PetscCall(PetscFree(reqs));

5961:   if (scall == MAT_INITIAL_MATRIX) {
5962:     /* put together the new matrix */
5963:     PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, aBn, B->cmap->N, b_othi, b_othj, b_otha, B_oth));

5965:     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5966:     /* Since these are PETSc arrays, change flags to free them as necessary. */
5967:     b_oth          = (Mat_SeqAIJ *)(*B_oth)->data;
5968:     b_oth->free_a  = PETSC_TRUE;
5969:     b_oth->free_ij = PETSC_TRUE;
5970:     b_oth->nonew   = 0;

5972:     PetscCall(PetscFree(bufj));
5973:     if (!startsj_s || !bufa_ptr) {
5974:       PetscCall(PetscFree2(sstartsj, rstartsj));
5975:       PetscCall(PetscFree(bufa_ptr));
5976:     } else {
5977:       *startsj_s = sstartsj;
5978:       *startsj_r = rstartsj;
5979:       *bufa_ptr  = bufa;
5980:     }
5981:   } else if (scall == MAT_REUSE_MATRIX) {
5982:     PetscCall(MatSeqAIJRestoreArrayWrite(*B_oth, &b_otha));
5983:   }

5985:   PetscCall(VecScatterRestoreRemote_Private(ctx, PETSC_TRUE, &nsends, &sstarts, &srow, &sprocs, &sbs));
5986:   PetscCall(VecScatterRestoreRemoteOrdered_Private(ctx, PETSC_FALSE, &nrecvs, &rstarts, NULL, &rprocs, &rbs));
5987:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAocols, A, B, 0, 0));
5988:   PetscFunctionReturn(PETSC_SUCCESS);
5989: }

5991: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCRL(Mat, MatType, MatReuse, Mat *);
5992: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJPERM(Mat, MatType, MatReuse, Mat *);
5993: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJSELL(Mat, MatType, MatReuse, Mat *);
5994: #if defined(PETSC_HAVE_MKL_SPARSE)
5995: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJMKL(Mat, MatType, MatReuse, Mat *);
5996: #endif
5997: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIBAIJ(Mat, MatType, MatReuse, Mat *);
5998: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPISBAIJ(Mat, MatType, MatReuse, Mat *);
5999: #if defined(PETSC_HAVE_ELEMENTAL)
6000: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_Elemental(Mat, MatType, MatReuse, Mat *);
6001: #endif
6002: #if defined(PETSC_HAVE_SCALAPACK)
6003: PETSC_INTERN PetscErrorCode MatConvert_AIJ_ScaLAPACK(Mat, MatType, MatReuse, Mat *);
6004: #endif
6005: #if defined(PETSC_HAVE_HYPRE)
6006: PETSC_INTERN PetscErrorCode MatConvert_AIJ_HYPRE(Mat, MatType, MatReuse, Mat *);
6007: #endif
6008: #if defined(PETSC_HAVE_CUDA)
6009: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCUSPARSE(Mat, MatType, MatReuse, Mat *);
6010: #endif
6011: #if defined(PETSC_HAVE_HIP)
6012: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJHIPSPARSE(Mat, MatType, MatReuse, Mat *);
6013: #endif
6014: #if defined(PETSC_HAVE_KOKKOS_KERNELS)
6015: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJKokkos(Mat, MatType, MatReuse, Mat *);
6016: #endif
6017: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPISELL(Mat, MatType, MatReuse, Mat *);
6018: PETSC_INTERN PetscErrorCode MatConvert_XAIJ_IS(Mat, MatType, MatReuse, Mat *);
6019: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_IS_XAIJ(Mat);

6021: /*
6022:     Computes (B'*A')' since computing B*A directly is untenable

6024:                n                       p                          p
6025:         [             ]       [             ]         [                 ]
6026:       m [      A      ]  *  n [       B     ]   =   m [         C       ]
6027:         [             ]       [             ]         [                 ]

6029: */
6030: static PetscErrorCode MatMatMultNumeric_MPIDense_MPIAIJ(Mat A, Mat B, Mat C)
6031: {
6032:   Mat At, Bt, Ct;

6034:   PetscFunctionBegin;
6035:   PetscCall(MatTranspose(A, MAT_INITIAL_MATRIX, &At));
6036:   PetscCall(MatTranspose(B, MAT_INITIAL_MATRIX, &Bt));
6037:   PetscCall(MatMatMult(Bt, At, MAT_INITIAL_MATRIX, PETSC_DEFAULT, &Ct));
6038:   PetscCall(MatDestroy(&At));
6039:   PetscCall(MatDestroy(&Bt));
6040:   PetscCall(MatTransposeSetPrecursor(Ct, C));
6041:   PetscCall(MatTranspose(Ct, MAT_REUSE_MATRIX, &C));
6042:   PetscCall(MatDestroy(&Ct));
6043:   PetscFunctionReturn(PETSC_SUCCESS);
6044: }

6046: static PetscErrorCode MatMatMultSymbolic_MPIDense_MPIAIJ(Mat A, Mat B, PetscReal fill, Mat C)
6047: {
6048:   PetscBool cisdense;

6050:   PetscFunctionBegin;
6051:   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);
6052:   PetscCall(MatSetSizes(C, A->rmap->n, B->cmap->n, A->rmap->N, B->cmap->N));
6053:   PetscCall(MatSetBlockSizesFromMats(C, A, B));
6054:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &cisdense, MATMPIDENSE, MATMPIDENSECUDA, MATMPIDENSEHIP, ""));
6055:   if (!cisdense) PetscCall(MatSetType(C, ((PetscObject)A)->type_name));
6056:   PetscCall(MatSetUp(C));

6058:   C->ops->matmultnumeric = MatMatMultNumeric_MPIDense_MPIAIJ;
6059:   PetscFunctionReturn(PETSC_SUCCESS);
6060: }

6062: static PetscErrorCode MatProductSetFromOptions_MPIDense_MPIAIJ_AB(Mat C)
6063: {
6064:   Mat_Product *product = C->product;
6065:   Mat          A = product->A, B = product->B;

6067:   PetscFunctionBegin;
6068:   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 ")",
6069:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
6070:   C->ops->matmultsymbolic = MatMatMultSymbolic_MPIDense_MPIAIJ;
6071:   C->ops->productsymbolic = MatProductSymbolic_AB;
6072:   PetscFunctionReturn(PETSC_SUCCESS);
6073: }

6075: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_MPIDense_MPIAIJ(Mat C)
6076: {
6077:   Mat_Product *product = C->product;

6079:   PetscFunctionBegin;
6080:   if (product->type == MATPRODUCT_AB) PetscCall(MatProductSetFromOptions_MPIDense_MPIAIJ_AB(C));
6081:   PetscFunctionReturn(PETSC_SUCCESS);
6082: }

6084: /*
6085:    Merge two sets of sorted nonzeros and return a CSR for the merged (sequential) matrix

6087:   Input Parameters:

6089:     j1,rowBegin1,rowEnd1,jmap1: describe the first set of nonzeros (Set1)
6090:     j2,rowBegin2,rowEnd2,jmap2: describe the second set of nonzeros (Set2)

6092:     mat: both sets' nonzeros are on m rows, where m is the number of local rows of the matrix mat

6094:     For Set1, j1[] contains column indices of the nonzeros.
6095:     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
6096:     respectively (note rowEnd1[k] is not necessarily equal to rwoBegin1[k+1]). Indices in this range of j1[] are sorted,
6097:     but might have repeats. jmap1[t+1] - jmap1[t] is the number of repeats for the t-th unique nonzero in Set1.

6099:     Similar for Set2.

6101:     This routine merges the two sets of nonzeros row by row and removes repeats.

6103:   Output Parameters: (memory is allocated by the caller)

6105:     i[],j[]: the CSR of the merged matrix, which has m rows.
6106:     imap1[]: the k-th unique nonzero in Set1 (k=0,1,...) corresponds to imap1[k]-th unique nonzero in the merged matrix.
6107:     imap2[]: similar to imap1[], but for Set2.
6108:     Note we order nonzeros row-by-row and from left to right.
6109: */
6110: 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[])
6111: {
6112:   PetscInt   r, m; /* Row index of mat */
6113:   PetscCount t, t1, t2, b1, e1, b2, e2;

6115:   PetscFunctionBegin;
6116:   PetscCall(MatGetLocalSize(mat, &m, NULL));
6117:   t1 = t2 = t = 0; /* Count unique nonzeros of in Set1, Set1 and the merged respectively */
6118:   i[0]        = 0;
6119:   for (r = 0; r < m; r++) { /* Do row by row merging */
6120:     b1 = rowBegin1[r];
6121:     e1 = rowEnd1[r];
6122:     b2 = rowBegin2[r];
6123:     e2 = rowEnd2[r];
6124:     while (b1 < e1 && b2 < e2) {
6125:       if (j1[b1] == j2[b2]) { /* Same column index and hence same nonzero */
6126:         j[t]      = j1[b1];
6127:         imap1[t1] = t;
6128:         imap2[t2] = t;
6129:         b1 += jmap1[t1 + 1] - jmap1[t1]; /* Jump to next unique local nonzero */
6130:         b2 += jmap2[t2 + 1] - jmap2[t2]; /* Jump to next unique remote nonzero */
6131:         t1++;
6132:         t2++;
6133:         t++;
6134:       } else if (j1[b1] < j2[b2]) {
6135:         j[t]      = j1[b1];
6136:         imap1[t1] = t;
6137:         b1 += jmap1[t1 + 1] - jmap1[t1];
6138:         t1++;
6139:         t++;
6140:       } else {
6141:         j[t]      = j2[b2];
6142:         imap2[t2] = t;
6143:         b2 += jmap2[t2 + 1] - jmap2[t2];
6144:         t2++;
6145:         t++;
6146:       }
6147:     }
6148:     /* Merge the remaining in either j1[] or j2[] */
6149:     while (b1 < e1) {
6150:       j[t]      = j1[b1];
6151:       imap1[t1] = t;
6152:       b1 += jmap1[t1 + 1] - jmap1[t1];
6153:       t1++;
6154:       t++;
6155:     }
6156:     while (b2 < e2) {
6157:       j[t]      = j2[b2];
6158:       imap2[t2] = t;
6159:       b2 += jmap2[t2 + 1] - jmap2[t2];
6160:       t2++;
6161:       t++;
6162:     }
6163:     i[r + 1] = t;
6164:   }
6165:   PetscFunctionReturn(PETSC_SUCCESS);
6166: }

6168: /*
6169:   Split nonzeros in a block of local rows into two subsets: those in the diagonal block and those in the off-diagonal block

6171:   Input Parameters:
6172:     mat: an MPI matrix that provides row and column layout information for splitting. Let's say its number of local rows is m.
6173:     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[]
6174:       respectively, along with a permutation array perm[]. Length of the i[],j[],perm[] arrays is n.

6176:       i[] is already sorted, but within a row, j[] is not sorted and might have repeats.
6177:       i[] might contain negative indices at the beginning, which means the corresponding entries should be ignored in the splitting.

6179:   Output Parameters:
6180:     j[],perm[]: the routine needs to sort j[] within each row along with perm[].
6181:     rowBegin[],rowMid[],rowEnd[]: of length m, and the memory is preallocated and zeroed by the caller.
6182:       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,
6183:       and [rowMid[r],rowEnd[r]) point to begin/end entries of row r of the off-diagonal block.

6185:     Aperm[],Ajmap[],Atot,Annz: Arrays are allocated by this routine.
6186:       Atot: number of entries belonging to the diagonal block.
6187:       Annz: number of unique nonzeros belonging to the diagonal block.
6188:       Aperm[Atot] stores values from perm[] for entries belonging to the diagonal block. Length of Aperm[] is Atot, though it may also count
6189:         repeats (i.e., same 'i,j' pair).
6190:       Ajmap[Annz+1] stores the number of repeats of each unique entry belonging to the diagonal block. More precisely, Ajmap[t+1] - Ajmap[t]
6191:         is the number of repeats for the t-th unique entry in the diagonal block. Ajmap[0] is always 0.

6193:       Atot: number of entries belonging to the diagonal block
6194:       Annz: number of unique nonzeros belonging to the diagonal block.

6196:     Bperm[], Bjmap[], Btot, Bnnz are similar but for the off-diagonal block.

6198:     Aperm[],Bperm[],Ajmap[] and Bjmap[] are allocated separately by this routine with PetscMalloc1().
6199: */
6200: 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_)
6201: {
6202:   PetscInt    cstart, cend, rstart, rend, row, col;
6203:   PetscCount  Atot = 0, Btot = 0; /* Total number of nonzeros in the diagonal and off-diagonal blocks */
6204:   PetscCount  Annz = 0, Bnnz = 0; /* Number of unique nonzeros in the diagonal and off-diagonal blocks */
6205:   PetscCount  k, m, p, q, r, s, mid;
6206:   PetscCount *Aperm, *Bperm, *Ajmap, *Bjmap;

6208:   PetscFunctionBegin;
6209:   PetscCall(PetscLayoutGetRange(mat->rmap, &rstart, &rend));
6210:   PetscCall(PetscLayoutGetRange(mat->cmap, &cstart, &cend));
6211:   m = rend - rstart;

6213:   /* Skip negative rows */
6214:   for (k = 0; k < n; k++)
6215:     if (i[k] >= 0) break;

6217:   /* Process [k,n): sort and partition each local row into diag and offdiag portions,
6218:      fill rowBegin[], rowMid[], rowEnd[], and count Atot, Btot, Annz, Bnnz.
6219:   */
6220:   while (k < n) {
6221:     row = i[k];
6222:     /* Entries in [k,s) are in one row. Shift diagonal block col indices so that diag is ahead of offdiag after sorting the row */
6223:     for (s = k; s < n; s++)
6224:       if (i[s] != row) break;

6226:     /* Shift diag columns to range of [-PETSC_MAX_INT, -1] */
6227:     for (p = k; p < s; p++) {
6228:       if (j[p] >= cstart && j[p] < cend) j[p] -= PETSC_MAX_INT;
6229:       else PetscAssert((j[p] >= 0) && (j[p] <= mat->cmap->N), PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column index %" PetscInt_FMT " is out of range", j[p]);
6230:     }
6231:     PetscCall(PetscSortIntWithCountArray(s - k, j + k, perm + k));
6232:     PetscCall(PetscSortedIntUpperBound(j, k, s, -1, &mid)); /* Separate [k,s) into [k,mid) for diag and [mid,s) for offdiag */
6233:     rowBegin[row - rstart] = k;
6234:     rowMid[row - rstart]   = mid;
6235:     rowEnd[row - rstart]   = s;

6237:     /* Count nonzeros of this diag/offdiag row, which might have repeats */
6238:     Atot += mid - k;
6239:     Btot += s - mid;

6241:     /* Count unique nonzeros of this diag row */
6242:     for (p = k; p < mid;) {
6243:       col = j[p];
6244:       do {
6245:         j[p] += PETSC_MAX_INT; /* Revert the modified diagonal indices */
6246:         p++;
6247:       } while (p < mid && j[p] == col);
6248:       Annz++;
6249:     }

6251:     /* Count unique nonzeros of this offdiag row */
6252:     for (p = mid; p < s;) {
6253:       col = j[p];
6254:       do {
6255:         p++;
6256:       } while (p < s && j[p] == col);
6257:       Bnnz++;
6258:     }
6259:     k = s;
6260:   }

6262:   /* Allocation according to Atot, Btot, Annz, Bnnz */
6263:   PetscCall(PetscMalloc1(Atot, &Aperm));
6264:   PetscCall(PetscMalloc1(Btot, &Bperm));
6265:   PetscCall(PetscMalloc1(Annz + 1, &Ajmap));
6266:   PetscCall(PetscMalloc1(Bnnz + 1, &Bjmap));

6268:   /* Re-scan indices and copy diag/offdiag permutation indices to Aperm, Bperm and also fill Ajmap and Bjmap */
6269:   Ajmap[0] = Bjmap[0] = Atot = Btot = Annz = Bnnz = 0;
6270:   for (r = 0; r < m; r++) {
6271:     k   = rowBegin[r];
6272:     mid = rowMid[r];
6273:     s   = rowEnd[r];
6274:     PetscCall(PetscArraycpy(Aperm + Atot, perm + k, mid - k));
6275:     PetscCall(PetscArraycpy(Bperm + Btot, perm + mid, s - mid));
6276:     Atot += mid - k;
6277:     Btot += s - mid;

6279:     /* Scan column indices in this row and find out how many repeats each unique nonzero has */
6280:     for (p = k; p < mid;) {
6281:       col = j[p];
6282:       q   = p;
6283:       do {
6284:         p++;
6285:       } while (p < mid && j[p] == col);
6286:       Ajmap[Annz + 1] = Ajmap[Annz] + (p - q);
6287:       Annz++;
6288:     }

6290:     for (p = mid; p < s;) {
6291:       col = j[p];
6292:       q   = p;
6293:       do {
6294:         p++;
6295:       } while (p < s && j[p] == col);
6296:       Bjmap[Bnnz + 1] = Bjmap[Bnnz] + (p - q);
6297:       Bnnz++;
6298:     }
6299:   }
6300:   /* Output */
6301:   *Aperm_ = Aperm;
6302:   *Annz_  = Annz;
6303:   *Atot_  = Atot;
6304:   *Ajmap_ = Ajmap;
6305:   *Bperm_ = Bperm;
6306:   *Bnnz_  = Bnnz;
6307:   *Btot_  = Btot;
6308:   *Bjmap_ = Bjmap;
6309:   PetscFunctionReturn(PETSC_SUCCESS);
6310: }

6312: /*
6313:   Expand the jmap[] array to make a new one in view of nonzeros in the merged matrix

6315:   Input Parameters:
6316:     nnz1: number of unique nonzeros in a set that was used to produce imap[], jmap[]
6317:     nnz:  number of unique nonzeros in the merged matrix
6318:     imap[nnz1]: i-th nonzero in the set is the imap[i]-th nonzero in the merged matrix
6319:     jmap[nnz1+1]: i-th nonzero in the set has jmap[i+1] - jmap[i] repeats in the set

6321:   Output Parameter: (memory is allocated by the caller)
6322:     jmap_new[nnz+1]: i-th nonzero in the merged matrix has jmap_new[i+1] - jmap_new[i] repeats in the set

6324:   Example:
6325:     nnz1 = 4
6326:     nnz  = 6
6327:     imap = [1,3,4,5]
6328:     jmap = [0,3,5,6,7]
6329:    then,
6330:     jmap_new = [0,0,3,3,5,6,7]
6331: */
6332: static PetscErrorCode ExpandJmap_Internal(PetscCount nnz1, PetscCount nnz, const PetscCount imap[], const PetscCount jmap[], PetscCount jmap_new[])
6333: {
6334:   PetscCount k, p;

6336:   PetscFunctionBegin;
6337:   jmap_new[0] = 0;
6338:   p           = nnz;                /* p loops over jmap_new[] backwards */
6339:   for (k = nnz1 - 1; k >= 0; k--) { /* k loops over imap[] */
6340:     for (; p > imap[k]; p--) jmap_new[p] = jmap[k + 1];
6341:   }
6342:   for (; p >= 0; p--) jmap_new[p] = jmap[0];
6343:   PetscFunctionReturn(PETSC_SUCCESS);
6344: }

6346: static PetscErrorCode MatCOOStructDestroy_MPIAIJ(void *data)
6347: {
6348:   MatCOOStruct_MPIAIJ *coo = (MatCOOStruct_MPIAIJ *)data;

6350:   PetscFunctionBegin;
6351:   PetscCall(PetscSFDestroy(&coo->sf));
6352:   PetscCall(PetscFree(coo->Aperm1));
6353:   PetscCall(PetscFree(coo->Bperm1));
6354:   PetscCall(PetscFree(coo->Ajmap1));
6355:   PetscCall(PetscFree(coo->Bjmap1));
6356:   PetscCall(PetscFree(coo->Aimap2));
6357:   PetscCall(PetscFree(coo->Bimap2));
6358:   PetscCall(PetscFree(coo->Aperm2));
6359:   PetscCall(PetscFree(coo->Bperm2));
6360:   PetscCall(PetscFree(coo->Ajmap2));
6361:   PetscCall(PetscFree(coo->Bjmap2));
6362:   PetscCall(PetscFree(coo->Cperm1));
6363:   PetscCall(PetscFree2(coo->sendbuf, coo->recvbuf));
6364:   PetscCall(PetscFree(coo));
6365:   PetscFunctionReturn(PETSC_SUCCESS);
6366: }

6368: PetscErrorCode MatSetPreallocationCOO_MPIAIJ(Mat mat, PetscCount coo_n, PetscInt coo_i[], PetscInt coo_j[])
6369: {
6370:   MPI_Comm             comm;
6371:   PetscMPIInt          rank, size;
6372:   PetscInt             m, n, M, N, rstart, rend, cstart, cend; /* Sizes, indices of row/col, therefore with type PetscInt */
6373:   PetscCount           k, p, q, rem;                           /* Loop variables over coo arrays */
6374:   Mat_MPIAIJ          *mpiaij = (Mat_MPIAIJ *)mat->data;
6375:   PetscContainer       container;
6376:   MatCOOStruct_MPIAIJ *coo;

6378:   PetscFunctionBegin;
6379:   PetscCall(PetscFree(mpiaij->garray));
6380:   PetscCall(VecDestroy(&mpiaij->lvec));
6381: #if defined(PETSC_USE_CTABLE)
6382:   PetscCall(PetscHMapIDestroy(&mpiaij->colmap));
6383: #else
6384:   PetscCall(PetscFree(mpiaij->colmap));
6385: #endif
6386:   PetscCall(VecScatterDestroy(&mpiaij->Mvctx));
6387:   mat->assembled     = PETSC_FALSE;
6388:   mat->was_assembled = PETSC_FALSE;

6390:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
6391:   PetscCallMPI(MPI_Comm_size(comm, &size));
6392:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
6393:   PetscCall(PetscLayoutSetUp(mat->rmap));
6394:   PetscCall(PetscLayoutSetUp(mat->cmap));
6395:   PetscCall(PetscLayoutGetRange(mat->rmap, &rstart, &rend));
6396:   PetscCall(PetscLayoutGetRange(mat->cmap, &cstart, &cend));
6397:   PetscCall(MatGetLocalSize(mat, &m, &n));
6398:   PetscCall(MatGetSize(mat, &M, &N));

6400:   /* Sort (i,j) by row along with a permutation array, so that the to-be-ignored */
6401:   /* entries come first, then local rows, then remote rows.                     */
6402:   PetscCount n1 = coo_n, *perm1;
6403:   PetscInt  *i1 = coo_i, *j1 = coo_j;

6405:   PetscCall(PetscMalloc1(n1, &perm1));
6406:   for (k = 0; k < n1; k++) perm1[k] = k;

6408:   /* Manipulate indices so that entries with negative row or col indices will have smallest
6409:      row indices, local entries will have greater but negative row indices, and remote entries
6410:      will have positive row indices.
6411:   */
6412:   for (k = 0; k < n1; k++) {
6413:     if (i1[k] < 0 || j1[k] < 0) i1[k] = PETSC_MIN_INT;                /* e.g., -2^31, minimal to move them ahead */
6414:     else if (i1[k] >= rstart && i1[k] < rend) i1[k] -= PETSC_MAX_INT; /* e.g., minus 2^31-1 to shift local rows to range of [-PETSC_MAX_INT, -1] */
6415:     else {
6416:       PetscCheck(!mat->nooffprocentries, PETSC_COMM_SELF, PETSC_ERR_USER_INPUT, "MAT_NO_OFF_PROC_ENTRIES is set but insert to remote rows");
6417:       if (mpiaij->donotstash) i1[k] = PETSC_MIN_INT; /* Ignore offproc entries as if they had negative indices */
6418:     }
6419:   }

6421:   /* Sort by row; after that, [0,k) have ignored entries, [k,rem) have local rows and [rem,n1) have remote rows */
6422:   PetscCall(PetscSortIntWithIntCountArrayPair(n1, i1, j1, perm1));

6424:   /* Advance k to the first entry we need to take care of */
6425:   for (k = 0; k < n1; k++)
6426:     if (i1[k] > PETSC_MIN_INT) break;
6427:   PetscInt i1start = k;

6429:   PetscCall(PetscSortedIntUpperBound(i1, k, n1, rend - 1 - PETSC_MAX_INT, &rem)); /* rem is upper bound of the last local row */
6430:   for (; k < rem; k++) i1[k] += PETSC_MAX_INT;                                    /* Revert row indices of local rows*/

6432:   /*           Send remote rows to their owner                                  */
6433:   /* Find which rows should be sent to which remote ranks*/
6434:   PetscInt        nsend = 0; /* Number of MPI ranks to send data to */
6435:   PetscMPIInt    *sendto;    /* [nsend], storing remote ranks */
6436:   PetscInt       *nentries;  /* [nsend], storing number of entries sent to remote ranks; Assume PetscInt is big enough for this count, and error if not */
6437:   const PetscInt *ranges;
6438:   PetscInt        maxNsend = size >= 128 ? 128 : size; /* Assume max 128 neighbors; realloc when needed */

6440:   PetscCall(PetscLayoutGetRanges(mat->rmap, &ranges));
6441:   PetscCall(PetscMalloc2(maxNsend, &sendto, maxNsend, &nentries));
6442:   for (k = rem; k < n1;) {
6443:     PetscMPIInt owner;
6444:     PetscInt    firstRow, lastRow;

6446:     /* Locate a row range */
6447:     firstRow = i1[k]; /* first row of this owner */
6448:     PetscCall(PetscLayoutFindOwner(mat->rmap, firstRow, &owner));
6449:     lastRow = ranges[owner + 1] - 1; /* last row of this owner */

6451:     /* Find the first index 'p' in [k,n) with i[p] belonging to next owner */
6452:     PetscCall(PetscSortedIntUpperBound(i1, k, n1, lastRow, &p));

6454:     /* All entries in [k,p) belong to this remote owner */
6455:     if (nsend >= maxNsend) { /* Double the remote ranks arrays if not long enough */
6456:       PetscMPIInt *sendto2;
6457:       PetscInt    *nentries2;
6458:       PetscInt     maxNsend2 = (maxNsend <= size / 2) ? maxNsend * 2 : size;

6460:       PetscCall(PetscMalloc2(maxNsend2, &sendto2, maxNsend2, &nentries2));
6461:       PetscCall(PetscArraycpy(sendto2, sendto, maxNsend));
6462:       PetscCall(PetscArraycpy(nentries2, nentries2, maxNsend + 1));
6463:       PetscCall(PetscFree2(sendto, nentries2));
6464:       sendto   = sendto2;
6465:       nentries = nentries2;
6466:       maxNsend = maxNsend2;
6467:     }
6468:     sendto[nsend]   = owner;
6469:     nentries[nsend] = p - k;
6470:     PetscCall(PetscCountCast(p - k, &nentries[nsend]));
6471:     nsend++;
6472:     k = p;
6473:   }

6475:   /* Build 1st SF to know offsets on remote to send data */
6476:   PetscSF      sf1;
6477:   PetscInt     nroots = 1, nroots2 = 0;
6478:   PetscInt     nleaves = nsend, nleaves2 = 0;
6479:   PetscInt    *offsets;
6480:   PetscSFNode *iremote;

6482:   PetscCall(PetscSFCreate(comm, &sf1));
6483:   PetscCall(PetscMalloc1(nsend, &iremote));
6484:   PetscCall(PetscMalloc1(nsend, &offsets));
6485:   for (k = 0; k < nsend; k++) {
6486:     iremote[k].rank  = sendto[k];
6487:     iremote[k].index = 0;
6488:     nleaves2 += nentries[k];
6489:     PetscCheck(nleaves2 >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of SF leaves is too large for PetscInt");
6490:   }
6491:   PetscCall(PetscSFSetGraph(sf1, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
6492:   PetscCall(PetscSFFetchAndOpWithMemTypeBegin(sf1, MPIU_INT, PETSC_MEMTYPE_HOST, &nroots2 /*rootdata*/, PETSC_MEMTYPE_HOST, nentries /*leafdata*/, PETSC_MEMTYPE_HOST, offsets /*leafupdate*/, MPI_SUM));
6493:   PetscCall(PetscSFFetchAndOpEnd(sf1, MPIU_INT, &nroots2, nentries, offsets, MPI_SUM)); /* Would nroots2 overflow, we check offsets[] below */
6494:   PetscCall(PetscSFDestroy(&sf1));
6495:   PetscAssert(nleaves2 == n1 - rem, PETSC_COMM_SELF, PETSC_ERR_PLIB, "nleaves2 %" PetscInt_FMT " != number of remote entries %" PetscCount_FMT "", nleaves2, n1 - rem);

6497:   /* Build 2nd SF to send remote COOs to their owner */
6498:   PetscSF sf2;
6499:   nroots  = nroots2;
6500:   nleaves = nleaves2;
6501:   PetscCall(PetscSFCreate(comm, &sf2));
6502:   PetscCall(PetscSFSetFromOptions(sf2));
6503:   PetscCall(PetscMalloc1(nleaves, &iremote));
6504:   p = 0;
6505:   for (k = 0; k < nsend; k++) {
6506:     PetscCheck(offsets[k] >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of SF roots is too large for PetscInt");
6507:     for (q = 0; q < nentries[k]; q++, p++) {
6508:       iremote[p].rank  = sendto[k];
6509:       iremote[p].index = offsets[k] + q;
6510:     }
6511:   }
6512:   PetscCall(PetscSFSetGraph(sf2, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));

6514:   /* Send the remote COOs to their owner */
6515:   PetscInt    n2 = nroots, *i2, *j2; /* Buffers for received COOs from other ranks, along with a permutation array */
6516:   PetscCount *perm2;                 /* Though PetscInt is enough for remote entries, we use PetscCount here as we want to reuse MatSplitEntries_Internal() */
6517:   PetscCall(PetscMalloc3(n2, &i2, n2, &j2, n2, &perm2));
6518:   PetscCall(PetscSFReduceWithMemTypeBegin(sf2, MPIU_INT, PETSC_MEMTYPE_HOST, i1 + rem, PETSC_MEMTYPE_HOST, i2, MPI_REPLACE));
6519:   PetscCall(PetscSFReduceEnd(sf2, MPIU_INT, i1 + rem, i2, MPI_REPLACE));
6520:   PetscCall(PetscSFReduceWithMemTypeBegin(sf2, MPIU_INT, PETSC_MEMTYPE_HOST, j1 + rem, PETSC_MEMTYPE_HOST, j2, MPI_REPLACE));
6521:   PetscCall(PetscSFReduceEnd(sf2, MPIU_INT, j1 + rem, j2, MPI_REPLACE));

6523:   PetscCall(PetscFree(offsets));
6524:   PetscCall(PetscFree2(sendto, nentries));

6526:   /* Sort received COOs by row along with the permutation array     */
6527:   for (k = 0; k < n2; k++) perm2[k] = k;
6528:   PetscCall(PetscSortIntWithIntCountArrayPair(n2, i2, j2, perm2));

6530:   /* sf2 only sends contiguous leafdata to contiguous rootdata. We record the permutation which will be used to fill leafdata */
6531:   PetscCount *Cperm1;
6532:   PetscCall(PetscMalloc1(nleaves, &Cperm1));
6533:   PetscCall(PetscArraycpy(Cperm1, perm1 + rem, nleaves));

6535:   /* Support for HYPRE matrices, kind of a hack.
6536:      Swap min column with diagonal so that diagonal values will go first */
6537:   PetscBool   hypre;
6538:   const char *name;
6539:   PetscCall(PetscObjectGetName((PetscObject)mat, &name));
6540:   PetscCall(PetscStrcmp("_internal_COO_mat_for_hypre", name, &hypre));
6541:   if (hypre) {
6542:     PetscInt *minj;
6543:     PetscBT   hasdiag;

6545:     PetscCall(PetscBTCreate(m, &hasdiag));
6546:     PetscCall(PetscMalloc1(m, &minj));
6547:     for (k = 0; k < m; k++) minj[k] = PETSC_MAX_INT;
6548:     for (k = i1start; k < rem; k++) {
6549:       if (j1[k] < cstart || j1[k] >= cend) continue;
6550:       const PetscInt rindex = i1[k] - rstart;
6551:       if ((j1[k] - cstart) == rindex) PetscCall(PetscBTSet(hasdiag, rindex));
6552:       minj[rindex] = PetscMin(minj[rindex], j1[k]);
6553:     }
6554:     for (k = 0; k < n2; k++) {
6555:       if (j2[k] < cstart || j2[k] >= cend) continue;
6556:       const PetscInt rindex = i2[k] - rstart;
6557:       if ((j2[k] - cstart) == rindex) PetscCall(PetscBTSet(hasdiag, rindex));
6558:       minj[rindex] = PetscMin(minj[rindex], j2[k]);
6559:     }
6560:     for (k = i1start; k < rem; k++) {
6561:       const PetscInt rindex = i1[k] - rstart;
6562:       if (j1[k] < cstart || j1[k] >= cend || !PetscBTLookup(hasdiag, rindex)) continue;
6563:       if (j1[k] == minj[rindex]) j1[k] = i1[k] + (cstart - rstart);
6564:       else if ((j1[k] - cstart) == rindex) j1[k] = minj[rindex];
6565:     }
6566:     for (k = 0; k < n2; k++) {
6567:       const PetscInt rindex = i2[k] - rstart;
6568:       if (j2[k] < cstart || j2[k] >= cend || !PetscBTLookup(hasdiag, rindex)) continue;
6569:       if (j2[k] == minj[rindex]) j2[k] = i2[k] + (cstart - rstart);
6570:       else if ((j2[k] - cstart) == rindex) j2[k] = minj[rindex];
6571:     }
6572:     PetscCall(PetscBTDestroy(&hasdiag));
6573:     PetscCall(PetscFree(minj));
6574:   }

6576:   /* Split local COOs and received COOs into diag/offdiag portions */
6577:   PetscCount *rowBegin1, *rowMid1, *rowEnd1;
6578:   PetscCount *Ajmap1, *Aperm1, *Bjmap1, *Bperm1;
6579:   PetscCount  Annz1, Bnnz1, Atot1, Btot1;
6580:   PetscCount *rowBegin2, *rowMid2, *rowEnd2;
6581:   PetscCount *Ajmap2, *Aperm2, *Bjmap2, *Bperm2;
6582:   PetscCount  Annz2, Bnnz2, Atot2, Btot2;

6584:   PetscCall(PetscCalloc3(m, &rowBegin1, m, &rowMid1, m, &rowEnd1));
6585:   PetscCall(PetscCalloc3(m, &rowBegin2, m, &rowMid2, m, &rowEnd2));
6586:   PetscCall(MatSplitEntries_Internal(mat, rem, i1, j1, perm1, rowBegin1, rowMid1, rowEnd1, &Atot1, &Aperm1, &Annz1, &Ajmap1, &Btot1, &Bperm1, &Bnnz1, &Bjmap1));
6587:   PetscCall(MatSplitEntries_Internal(mat, n2, i2, j2, perm2, rowBegin2, rowMid2, rowEnd2, &Atot2, &Aperm2, &Annz2, &Ajmap2, &Btot2, &Bperm2, &Bnnz2, &Bjmap2));

6589:   /* Merge local COOs with received COOs: diag with diag, offdiag with offdiag */
6590:   PetscInt *Ai, *Bi;
6591:   PetscInt *Aj, *Bj;

6593:   PetscCall(PetscMalloc1(m + 1, &Ai));
6594:   PetscCall(PetscMalloc1(m + 1, &Bi));
6595:   PetscCall(PetscMalloc1(Annz1 + Annz2, &Aj)); /* Since local and remote entries might have dups, we might allocate excess memory */
6596:   PetscCall(PetscMalloc1(Bnnz1 + Bnnz2, &Bj));

6598:   PetscCount *Aimap1, *Bimap1, *Aimap2, *Bimap2;
6599:   PetscCall(PetscMalloc1(Annz1, &Aimap1));
6600:   PetscCall(PetscMalloc1(Bnnz1, &Bimap1));
6601:   PetscCall(PetscMalloc1(Annz2, &Aimap2));
6602:   PetscCall(PetscMalloc1(Bnnz2, &Bimap2));

6604:   PetscCall(MatMergeEntries_Internal(mat, j1, j2, rowBegin1, rowMid1, rowBegin2, rowMid2, Ajmap1, Ajmap2, Aimap1, Aimap2, Ai, Aj));
6605:   PetscCall(MatMergeEntries_Internal(mat, j1, j2, rowMid1, rowEnd1, rowMid2, rowEnd2, Bjmap1, Bjmap2, Bimap1, Bimap2, Bi, Bj));

6607:   /* Expand Ajmap1/Bjmap1 to make them based off nonzeros in A/B, since we     */
6608:   /* expect nonzeros in A/B most likely have local contributing entries        */
6609:   PetscInt    Annz = Ai[m];
6610:   PetscInt    Bnnz = Bi[m];
6611:   PetscCount *Ajmap1_new, *Bjmap1_new;

6613:   PetscCall(PetscMalloc1(Annz + 1, &Ajmap1_new));
6614:   PetscCall(PetscMalloc1(Bnnz + 1, &Bjmap1_new));

6616:   PetscCall(ExpandJmap_Internal(Annz1, Annz, Aimap1, Ajmap1, Ajmap1_new));
6617:   PetscCall(ExpandJmap_Internal(Bnnz1, Bnnz, Bimap1, Bjmap1, Bjmap1_new));

6619:   PetscCall(PetscFree(Aimap1));
6620:   PetscCall(PetscFree(Ajmap1));
6621:   PetscCall(PetscFree(Bimap1));
6622:   PetscCall(PetscFree(Bjmap1));
6623:   PetscCall(PetscFree3(rowBegin1, rowMid1, rowEnd1));
6624:   PetscCall(PetscFree3(rowBegin2, rowMid2, rowEnd2));
6625:   PetscCall(PetscFree(perm1));
6626:   PetscCall(PetscFree3(i2, j2, perm2));

6628:   Ajmap1 = Ajmap1_new;
6629:   Bjmap1 = Bjmap1_new;

6631:   /* Reallocate Aj, Bj once we know actual numbers of unique nonzeros in A and B */
6632:   if (Annz < Annz1 + Annz2) {
6633:     PetscInt *Aj_new;
6634:     PetscCall(PetscMalloc1(Annz, &Aj_new));
6635:     PetscCall(PetscArraycpy(Aj_new, Aj, Annz));
6636:     PetscCall(PetscFree(Aj));
6637:     Aj = Aj_new;
6638:   }

6640:   if (Bnnz < Bnnz1 + Bnnz2) {
6641:     PetscInt *Bj_new;
6642:     PetscCall(PetscMalloc1(Bnnz, &Bj_new));
6643:     PetscCall(PetscArraycpy(Bj_new, Bj, Bnnz));
6644:     PetscCall(PetscFree(Bj));
6645:     Bj = Bj_new;
6646:   }

6648:   /* Create new submatrices for on-process and off-process coupling                  */
6649:   PetscScalar     *Aa, *Ba;
6650:   MatType          rtype;
6651:   Mat_SeqAIJ      *a, *b;
6652:   PetscObjectState state;
6653:   PetscCall(PetscCalloc1(Annz, &Aa)); /* Zero matrix on device */
6654:   PetscCall(PetscCalloc1(Bnnz, &Ba));
6655:   /* make Aj[] local, i.e, based off the start column of the diagonal portion */
6656:   if (cstart) {
6657:     for (k = 0; k < Annz; k++) Aj[k] -= cstart;
6658:   }
6659:   PetscCall(MatDestroy(&mpiaij->A));
6660:   PetscCall(MatDestroy(&mpiaij->B));
6661:   PetscCall(MatGetRootType_Private(mat, &rtype));
6662:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, n, Ai, Aj, Aa, &mpiaij->A));
6663:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, mat->cmap->N, Bi, Bj, Ba, &mpiaij->B));
6664:   PetscCall(MatSetUpMultiply_MPIAIJ(mat));
6665:   mat->was_assembled = PETSC_TRUE; // was_assembled in effect means the Mvctx is built; doing so avoids redundant MatSetUpMultiply_MPIAIJ
6666:   state              = mpiaij->A->nonzerostate + mpiaij->B->nonzerostate;
6667:   PetscCall(MPIU_Allreduce(&state, &mat->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)mat)));

6669:   a               = (Mat_SeqAIJ *)mpiaij->A->data;
6670:   b               = (Mat_SeqAIJ *)mpiaij->B->data;
6671:   a->singlemalloc = b->singlemalloc = PETSC_FALSE; /* Let newmat own Ai,Aj,Aa,Bi,Bj,Ba */
6672:   a->free_a = b->free_a = PETSC_TRUE;
6673:   a->free_ij = b->free_ij = PETSC_TRUE;

6675:   /* conversion must happen AFTER multiply setup */
6676:   PetscCall(MatConvert(mpiaij->A, rtype, MAT_INPLACE_MATRIX, &mpiaij->A));
6677:   PetscCall(MatConvert(mpiaij->B, rtype, MAT_INPLACE_MATRIX, &mpiaij->B));
6678:   PetscCall(VecDestroy(&mpiaij->lvec));
6679:   PetscCall(MatCreateVecs(mpiaij->B, &mpiaij->lvec, NULL));

6681:   // Put the COO struct in a container and then attach that to the matrix
6682:   PetscCall(PetscMalloc1(1, &coo));
6683:   coo->n       = coo_n;
6684:   coo->sf      = sf2;
6685:   coo->sendlen = nleaves;
6686:   coo->recvlen = nroots;
6687:   coo->Annz    = Annz;
6688:   coo->Bnnz    = Bnnz;
6689:   coo->Annz2   = Annz2;
6690:   coo->Bnnz2   = Bnnz2;
6691:   coo->Atot1   = Atot1;
6692:   coo->Atot2   = Atot2;
6693:   coo->Btot1   = Btot1;
6694:   coo->Btot2   = Btot2;
6695:   coo->Ajmap1  = Ajmap1;
6696:   coo->Aperm1  = Aperm1;
6697:   coo->Bjmap1  = Bjmap1;
6698:   coo->Bperm1  = Bperm1;
6699:   coo->Aimap2  = Aimap2;
6700:   coo->Ajmap2  = Ajmap2;
6701:   coo->Aperm2  = Aperm2;
6702:   coo->Bimap2  = Bimap2;
6703:   coo->Bjmap2  = Bjmap2;
6704:   coo->Bperm2  = Bperm2;
6705:   coo->Cperm1  = Cperm1;
6706:   // Allocate in preallocation. If not used, it has zero cost on host
6707:   PetscCall(PetscMalloc2(coo->sendlen, &coo->sendbuf, coo->recvlen, &coo->recvbuf));
6708:   PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &container));
6709:   PetscCall(PetscContainerSetPointer(container, coo));
6710:   PetscCall(PetscContainerSetUserDestroy(container, MatCOOStructDestroy_MPIAIJ));
6711:   PetscCall(PetscObjectCompose((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject)container));
6712:   PetscCall(PetscContainerDestroy(&container));
6713:   PetscFunctionReturn(PETSC_SUCCESS);
6714: }

6716: static PetscErrorCode MatSetValuesCOO_MPIAIJ(Mat mat, const PetscScalar v[], InsertMode imode)
6717: {
6718:   Mat_MPIAIJ          *mpiaij = (Mat_MPIAIJ *)mat->data;
6719:   Mat                  A = mpiaij->A, B = mpiaij->B;
6720:   PetscScalar         *Aa, *Ba;
6721:   PetscScalar         *sendbuf, *recvbuf;
6722:   const PetscCount    *Ajmap1, *Ajmap2, *Aimap2;
6723:   const PetscCount    *Bjmap1, *Bjmap2, *Bimap2;
6724:   const PetscCount    *Aperm1, *Aperm2, *Bperm1, *Bperm2;
6725:   const PetscCount    *Cperm1;
6726:   PetscContainer       container;
6727:   MatCOOStruct_MPIAIJ *coo;

6729:   PetscFunctionBegin;
6730:   PetscCall(PetscObjectQuery((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject *)&container));
6731:   PetscCheck(container, PetscObjectComm((PetscObject)mat), PETSC_ERR_PLIB, "Not found MatCOOStruct on this matrix");
6732:   PetscCall(PetscContainerGetPointer(container, (void **)&coo));
6733:   sendbuf = coo->sendbuf;
6734:   recvbuf = coo->recvbuf;
6735:   Ajmap1  = coo->Ajmap1;
6736:   Ajmap2  = coo->Ajmap2;
6737:   Aimap2  = coo->Aimap2;
6738:   Bjmap1  = coo->Bjmap1;
6739:   Bjmap2  = coo->Bjmap2;
6740:   Bimap2  = coo->Bimap2;
6741:   Aperm1  = coo->Aperm1;
6742:   Aperm2  = coo->Aperm2;
6743:   Bperm1  = coo->Bperm1;
6744:   Bperm2  = coo->Bperm2;
6745:   Cperm1  = coo->Cperm1;

6747:   PetscCall(MatSeqAIJGetArray(A, &Aa)); /* Might read and write matrix values */
6748:   PetscCall(MatSeqAIJGetArray(B, &Ba));

6750:   /* Pack entries to be sent to remote */
6751:   for (PetscCount i = 0; i < coo->sendlen; i++) sendbuf[i] = v[Cperm1[i]];

6753:   /* Send remote entries to their owner and overlap the communication with local computation */
6754:   PetscCall(PetscSFReduceWithMemTypeBegin(coo->sf, MPIU_SCALAR, PETSC_MEMTYPE_HOST, sendbuf, PETSC_MEMTYPE_HOST, recvbuf, MPI_REPLACE));
6755:   /* Add local entries to A and B */
6756:   for (PetscCount i = 0; i < coo->Annz; i++) { /* All nonzeros in A are either zero'ed or added with a value (i.e., initialized) */
6757:     PetscScalar sum = 0.0;                     /* Do partial summation first to improve numerical stability */
6758:     for (PetscCount k = Ajmap1[i]; k < Ajmap1[i + 1]; k++) sum += v[Aperm1[k]];
6759:     Aa[i] = (imode == INSERT_VALUES ? 0.0 : Aa[i]) + sum;
6760:   }
6761:   for (PetscCount i = 0; i < coo->Bnnz; i++) {
6762:     PetscScalar sum = 0.0;
6763:     for (PetscCount k = Bjmap1[i]; k < Bjmap1[i + 1]; k++) sum += v[Bperm1[k]];
6764:     Ba[i] = (imode == INSERT_VALUES ? 0.0 : Ba[i]) + sum;
6765:   }
6766:   PetscCall(PetscSFReduceEnd(coo->sf, MPIU_SCALAR, sendbuf, recvbuf, MPI_REPLACE));

6768:   /* Add received remote entries to A and B */
6769:   for (PetscCount i = 0; i < coo->Annz2; i++) {
6770:     for (PetscCount k = Ajmap2[i]; k < Ajmap2[i + 1]; k++) Aa[Aimap2[i]] += recvbuf[Aperm2[k]];
6771:   }
6772:   for (PetscCount i = 0; i < coo->Bnnz2; i++) {
6773:     for (PetscCount k = Bjmap2[i]; k < Bjmap2[i + 1]; k++) Ba[Bimap2[i]] += recvbuf[Bperm2[k]];
6774:   }
6775:   PetscCall(MatSeqAIJRestoreArray(A, &Aa));
6776:   PetscCall(MatSeqAIJRestoreArray(B, &Ba));
6777:   PetscFunctionReturn(PETSC_SUCCESS);
6778: }

6780: /*MC
6781:    MATMPIAIJ - MATMPIAIJ = "mpiaij" - A matrix type to be used for parallel sparse matrices.

6783:    Options Database Keys:
6784: . -mat_type mpiaij - sets the matrix type to `MATMPIAIJ` during a call to `MatSetFromOptions()`

6786:    Level: beginner

6788:    Notes:
6789:    `MatSetValues()` may be called for this matrix type with a `NULL` argument for the numerical values,
6790:     in this case the values associated with the rows and columns one passes in are set to zero
6791:     in the matrix

6793:     `MatSetOptions`(,`MAT_STRUCTURE_ONLY`,`PETSC_TRUE`) may be called for this matrix type. In this no
6794:     space is allocated for the nonzero entries and any entries passed with `MatSetValues()` are ignored

6796: .seealso: [](ch_matrices), `Mat`, `MATSEQAIJ`, `MATAIJ`, `MatCreateAIJ()`
6797: M*/
6798: PETSC_EXTERN PetscErrorCode MatCreate_MPIAIJ(Mat B)
6799: {
6800:   Mat_MPIAIJ *b;
6801:   PetscMPIInt size;

6803:   PetscFunctionBegin;
6804:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)B), &size));

6806:   PetscCall(PetscNew(&b));
6807:   B->data       = (void *)b;
6808:   B->ops[0]     = MatOps_Values;
6809:   B->assembled  = PETSC_FALSE;
6810:   B->insertmode = NOT_SET_VALUES;
6811:   b->size       = size;

6813:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)B), &b->rank));

6815:   /* build cache for off array entries formed */
6816:   PetscCall(MatStashCreate_Private(PetscObjectComm((PetscObject)B), 1, &B->stash));

6818:   b->donotstash  = PETSC_FALSE;
6819:   b->colmap      = NULL;
6820:   b->garray      = NULL;
6821:   b->roworiented = PETSC_TRUE;

6823:   /* stuff used for matrix vector multiply */
6824:   b->lvec  = NULL;
6825:   b->Mvctx = NULL;

6827:   /* stuff for MatGetRow() */
6828:   b->rowindices   = NULL;
6829:   b->rowvalues    = NULL;
6830:   b->getrowactive = PETSC_FALSE;

6832:   /* flexible pointer used in CUSPARSE classes */
6833:   b->spptr = NULL;

6835:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetUseScalableIncreaseOverlap_C", MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ));
6836:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatStoreValues_C", MatStoreValues_MPIAIJ));
6837:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatRetrieveValues_C", MatRetrieveValues_MPIAIJ));
6838:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatIsTranspose_C", MatIsTranspose_MPIAIJ));
6839:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetPreallocation_C", MatMPIAIJSetPreallocation_MPIAIJ));
6840:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatResetPreallocation_C", MatResetPreallocation_MPIAIJ));
6841:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetPreallocationCSR_C", MatMPIAIJSetPreallocationCSR_MPIAIJ));
6842:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatDiagonalScaleLocal_C", MatDiagonalScaleLocal_MPIAIJ));
6843:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijperm_C", MatConvert_MPIAIJ_MPIAIJPERM));
6844:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijsell_C", MatConvert_MPIAIJ_MPIAIJSELL));
6845: #if defined(PETSC_HAVE_CUDA)
6846:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijcusparse_C", MatConvert_MPIAIJ_MPIAIJCUSPARSE));
6847: #endif
6848: #if defined(PETSC_HAVE_HIP)
6849:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijhipsparse_C", MatConvert_MPIAIJ_MPIAIJHIPSPARSE));
6850: #endif
6851: #if defined(PETSC_HAVE_KOKKOS_KERNELS)
6852:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijkokkos_C", MatConvert_MPIAIJ_MPIAIJKokkos));
6853: #endif
6854: #if defined(PETSC_HAVE_MKL_SPARSE)
6855:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijmkl_C", MatConvert_MPIAIJ_MPIAIJMKL));
6856: #endif
6857:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijcrl_C", MatConvert_MPIAIJ_MPIAIJCRL));
6858:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpibaij_C", MatConvert_MPIAIJ_MPIBAIJ));
6859:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpisbaij_C", MatConvert_MPIAIJ_MPISBAIJ));
6860:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpidense_C", MatConvert_MPIAIJ_MPIDense));
6861: #if defined(PETSC_HAVE_ELEMENTAL)
6862:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_elemental_C", MatConvert_MPIAIJ_Elemental));
6863: #endif
6864: #if defined(PETSC_HAVE_SCALAPACK)
6865:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_scalapack_C", MatConvert_AIJ_ScaLAPACK));
6866: #endif
6867:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_is_C", MatConvert_XAIJ_IS));
6868:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpisell_C", MatConvert_MPIAIJ_MPISELL));
6869: #if defined(PETSC_HAVE_HYPRE)
6870:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_hypre_C", MatConvert_AIJ_HYPRE));
6871:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_transpose_mpiaij_mpiaij_C", MatProductSetFromOptions_Transpose_AIJ_AIJ));
6872: #endif
6873:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_is_mpiaij_C", MatProductSetFromOptions_IS_XAIJ));
6874:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_mpiaij_mpiaij_C", MatProductSetFromOptions_MPIAIJ));
6875:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatSetPreallocationCOO_C", MatSetPreallocationCOO_MPIAIJ));
6876:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatSetValuesCOO_C", MatSetValuesCOO_MPIAIJ));
6877:   PetscCall(PetscObjectChangeTypeName((PetscObject)B, MATMPIAIJ));
6878:   PetscFunctionReturn(PETSC_SUCCESS);
6879: }

6881: /*@C
6882:   MatCreateMPIAIJWithSplitArrays - creates a `MATMPIAIJ` matrix using arrays that contain the "diagonal"
6883:   and "off-diagonal" part of the matrix in CSR format.

6885:   Collective

6887:   Input Parameters:
6888: + comm - MPI communicator
6889: . m    - number of local rows (Cannot be `PETSC_DECIDE`)
6890: . n    - This value should be the same as the local size used in creating the
6891:        x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
6892:        calculated if `N` is given) For square matrices `n` is almost always `m`.
6893: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if `m` is given)
6894: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if `n` is given)
6895: . 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
6896: . j    - column indices, which must be local, i.e., based off the start column of the diagonal portion
6897: . a    - matrix values
6898: . 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
6899: . oj   - column indices, which must be global, representing global columns in the `MATMPIAIJ` matrix
6900: - oa   - matrix values

6902:   Output Parameter:
6903: . mat - the matrix

6905:   Level: advanced

6907:   Notes:
6908:   The `i`, `j`, and `a` arrays ARE NOT copied by this routine into the internal format used by PETSc. The user
6909:   must free the arrays once the matrix has been destroyed and not before.

6911:   The `i` and `j` indices are 0 based

6913:   See `MatCreateAIJ()` for the definition of "diagonal" and "off-diagonal" portion of the matrix

6915:   This sets local rows and cannot be used to set off-processor values.

6917:   Use of this routine is discouraged because it is inflexible and cumbersome to use. It is extremely rare that a
6918:   legacy application natively assembles into exactly this split format. The code to do so is nontrivial and does
6919:   not easily support in-place reassembly. It is recommended to use MatSetValues() (or a variant thereof) because
6920:   the resulting assembly is easier to implement, will work with any matrix format, and the user does not have to
6921:   keep track of the underlying array. Use `MatSetOption`(A,`MAT_NO_OFF_PROC_ENTRIES`,`PETSC_TRUE`) to disable all
6922:   communication if it is known that only local entries will be set.

6924: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
6925:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithArrays()`
6926: @*/
6927: 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)
6928: {
6929:   Mat_MPIAIJ *maij;

6931:   PetscFunctionBegin;
6932:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
6933:   PetscCheck(i[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
6934:   PetscCheck(oi[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "oi (row indices) must start with 0");
6935:   PetscCall(MatCreate(comm, mat));
6936:   PetscCall(MatSetSizes(*mat, m, n, M, N));
6937:   PetscCall(MatSetType(*mat, MATMPIAIJ));
6938:   maij = (Mat_MPIAIJ *)(*mat)->data;

6940:   (*mat)->preallocated = PETSC_TRUE;

6942:   PetscCall(PetscLayoutSetUp((*mat)->rmap));
6943:   PetscCall(PetscLayoutSetUp((*mat)->cmap));

6945:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, n, i, j, a, &maij->A));
6946:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, (*mat)->cmap->N, oi, oj, oa, &maij->B));

6948:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
6949:   PetscCall(MatAssemblyBegin(*mat, MAT_FINAL_ASSEMBLY));
6950:   PetscCall(MatAssemblyEnd(*mat, MAT_FINAL_ASSEMBLY));
6951:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_FALSE));
6952:   PetscCall(MatSetOption(*mat, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
6953:   PetscFunctionReturn(PETSC_SUCCESS);
6954: }

6956: typedef struct {
6957:   Mat       *mp;    /* intermediate products */
6958:   PetscBool *mptmp; /* is the intermediate product temporary ? */
6959:   PetscInt   cp;    /* number of intermediate products */

6961:   /* support for MatGetBrowsOfAoCols_MPIAIJ for P_oth */
6962:   PetscInt    *startsj_s, *startsj_r;
6963:   PetscScalar *bufa;
6964:   Mat          P_oth;

6966:   /* may take advantage of merging product->B */
6967:   Mat Bloc; /* B-local by merging diag and off-diag */

6969:   /* cusparse does not have support to split between symbolic and numeric phases.
6970:      When api_user is true, we don't need to update the numerical values
6971:      of the temporary storage */
6972:   PetscBool reusesym;

6974:   /* support for COO values insertion */
6975:   PetscScalar *coo_v, *coo_w; /* store on-process and off-process COO scalars, and used as MPI recv/send buffers respectively */
6976:   PetscInt   **own;           /* own[i] points to address of on-process COO indices for Mat mp[i] */
6977:   PetscInt   **off;           /* off[i] points to address of off-process COO indices for Mat mp[i] */
6978:   PetscBool    hasoffproc;    /* if true, have off-process values insertion (i.e. AtB or PtAP) */
6979:   PetscSF      sf;            /* used for non-local values insertion and memory malloc */
6980:   PetscMemType mtype;

6982:   /* customization */
6983:   PetscBool abmerge;
6984:   PetscBool P_oth_bind;
6985: } MatMatMPIAIJBACKEND;

6987: static PetscErrorCode MatDestroy_MatMatMPIAIJBACKEND(void *data)
6988: {
6989:   MatMatMPIAIJBACKEND *mmdata = (MatMatMPIAIJBACKEND *)data;
6990:   PetscInt             i;

6992:   PetscFunctionBegin;
6993:   PetscCall(PetscFree2(mmdata->startsj_s, mmdata->startsj_r));
6994:   PetscCall(PetscFree(mmdata->bufa));
6995:   PetscCall(PetscSFFree(mmdata->sf, mmdata->mtype, mmdata->coo_v));
6996:   PetscCall(PetscSFFree(mmdata->sf, mmdata->mtype, mmdata->coo_w));
6997:   PetscCall(MatDestroy(&mmdata->P_oth));
6998:   PetscCall(MatDestroy(&mmdata->Bloc));
6999:   PetscCall(PetscSFDestroy(&mmdata->sf));
7000:   for (i = 0; i < mmdata->cp; i++) PetscCall(MatDestroy(&mmdata->mp[i]));
7001:   PetscCall(PetscFree2(mmdata->mp, mmdata->mptmp));
7002:   PetscCall(PetscFree(mmdata->own[0]));
7003:   PetscCall(PetscFree(mmdata->own));
7004:   PetscCall(PetscFree(mmdata->off[0]));
7005:   PetscCall(PetscFree(mmdata->off));
7006:   PetscCall(PetscFree(mmdata));
7007:   PetscFunctionReturn(PETSC_SUCCESS);
7008: }

7010: /* Copy selected n entries with indices in idx[] of A to v[].
7011:    If idx is NULL, copy the whole data array of A to v[]
7012:  */
7013: static PetscErrorCode MatSeqAIJCopySubArray(Mat A, PetscInt n, const PetscInt idx[], PetscScalar v[])
7014: {
7015:   PetscErrorCode (*f)(Mat, PetscInt, const PetscInt[], PetscScalar[]);

7017:   PetscFunctionBegin;
7018:   PetscCall(PetscObjectQueryFunction((PetscObject)A, "MatSeqAIJCopySubArray_C", &f));
7019:   if (f) {
7020:     PetscCall((*f)(A, n, idx, v));
7021:   } else {
7022:     const PetscScalar *vv;

7024:     PetscCall(MatSeqAIJGetArrayRead(A, &vv));
7025:     if (n && idx) {
7026:       PetscScalar    *w  = v;
7027:       const PetscInt *oi = idx;
7028:       PetscInt        j;

7030:       for (j = 0; j < n; j++) *w++ = vv[*oi++];
7031:     } else {
7032:       PetscCall(PetscArraycpy(v, vv, n));
7033:     }
7034:     PetscCall(MatSeqAIJRestoreArrayRead(A, &vv));
7035:   }
7036:   PetscFunctionReturn(PETSC_SUCCESS);
7037: }

7039: static PetscErrorCode MatProductNumeric_MPIAIJBACKEND(Mat C)
7040: {
7041:   MatMatMPIAIJBACKEND *mmdata;
7042:   PetscInt             i, n_d, n_o;

7044:   PetscFunctionBegin;
7045:   MatCheckProduct(C, 1);
7046:   PetscCheck(C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data empty");
7047:   mmdata = (MatMatMPIAIJBACKEND *)C->product->data;
7048:   if (!mmdata->reusesym) { /* update temporary matrices */
7049:     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));
7050:     if (mmdata->Bloc) PetscCall(MatMPIAIJGetLocalMatMerge(C->product->B, MAT_REUSE_MATRIX, NULL, &mmdata->Bloc));
7051:   }
7052:   mmdata->reusesym = PETSC_FALSE;

7054:   for (i = 0; i < mmdata->cp; i++) {
7055:     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]);
7056:     PetscCall((*mmdata->mp[i]->ops->productnumeric)(mmdata->mp[i]));
7057:   }
7058:   for (i = 0, n_d = 0, n_o = 0; i < mmdata->cp; i++) {
7059:     PetscInt noff = mmdata->off[i + 1] - mmdata->off[i];

7061:     if (mmdata->mptmp[i]) continue;
7062:     if (noff) {
7063:       PetscInt nown = mmdata->own[i + 1] - mmdata->own[i];

7065:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], noff, mmdata->off[i], mmdata->coo_w + n_o));
7066:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], nown, mmdata->own[i], mmdata->coo_v + n_d));
7067:       n_o += noff;
7068:       n_d += nown;
7069:     } else {
7070:       Mat_SeqAIJ *mm = (Mat_SeqAIJ *)mmdata->mp[i]->data;

7072:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], mm->nz, NULL, mmdata->coo_v + n_d));
7073:       n_d += mm->nz;
7074:     }
7075:   }
7076:   if (mmdata->hasoffproc) { /* offprocess insertion */
7077:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_SCALAR, mmdata->coo_w, mmdata->coo_v + n_d));
7078:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_SCALAR, mmdata->coo_w, mmdata->coo_v + n_d));
7079:   }
7080:   PetscCall(MatSetValuesCOO(C, mmdata->coo_v, INSERT_VALUES));
7081:   PetscFunctionReturn(PETSC_SUCCESS);
7082: }

7084: /* Support for Pt * A, A * P, or Pt * A * P */
7085: #define MAX_NUMBER_INTERMEDIATE 4
7086: PetscErrorCode MatProductSymbolic_MPIAIJBACKEND(Mat C)
7087: {
7088:   Mat_Product           *product = C->product;
7089:   Mat                    A, P, mp[MAX_NUMBER_INTERMEDIATE]; /* A, P and a series of intermediate matrices */
7090:   Mat_MPIAIJ            *a, *p;
7091:   MatMatMPIAIJBACKEND   *mmdata;
7092:   ISLocalToGlobalMapping P_oth_l2g = NULL;
7093:   IS                     glob      = NULL;
7094:   const char            *prefix;
7095:   char                   pprefix[256];
7096:   const PetscInt        *globidx, *P_oth_idx;
7097:   PetscInt               i, j, cp, m, n, M, N, *coo_i, *coo_j;
7098:   PetscCount             ncoo, ncoo_d, ncoo_o, ncoo_oown;
7099:   PetscInt               cmapt[MAX_NUMBER_INTERMEDIATE], rmapt[MAX_NUMBER_INTERMEDIATE]; /* col/row map type for each Mat in mp[]. */
7100:                                                                                          /* type-0: consecutive, start from 0; type-1: consecutive with */
7101:                                                                                          /* a base offset; type-2: sparse with a local to global map table */
7102:   const PetscInt *cmapa[MAX_NUMBER_INTERMEDIATE], *rmapa[MAX_NUMBER_INTERMEDIATE];       /* col/row local to global map array (table) for type-2 map type */

7104:   MatProductType ptype;
7105:   PetscBool      mptmp[MAX_NUMBER_INTERMEDIATE], hasoffproc = PETSC_FALSE, iscuda, iship, iskokk;
7106:   PetscMPIInt    size;

7108:   PetscFunctionBegin;
7109:   MatCheckProduct(C, 1);
7110:   PetscCheck(!product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data not empty");
7111:   ptype = product->type;
7112:   if (product->A->symmetric == PETSC_BOOL3_TRUE && ptype == MATPRODUCT_AtB) {
7113:     ptype                                          = MATPRODUCT_AB;
7114:     product->symbolic_used_the_fact_A_is_symmetric = PETSC_TRUE;
7115:   }
7116:   switch (ptype) {
7117:   case MATPRODUCT_AB:
7118:     A          = product->A;
7119:     P          = product->B;
7120:     m          = A->rmap->n;
7121:     n          = P->cmap->n;
7122:     M          = A->rmap->N;
7123:     N          = P->cmap->N;
7124:     hasoffproc = PETSC_FALSE; /* will not scatter mat product values to other processes */
7125:     break;
7126:   case MATPRODUCT_AtB:
7127:     P          = product->A;
7128:     A          = product->B;
7129:     m          = P->cmap->n;
7130:     n          = A->cmap->n;
7131:     M          = P->cmap->N;
7132:     N          = A->cmap->N;
7133:     hasoffproc = PETSC_TRUE;
7134:     break;
7135:   case MATPRODUCT_PtAP:
7136:     A          = product->A;
7137:     P          = product->B;
7138:     m          = P->cmap->n;
7139:     n          = P->cmap->n;
7140:     M          = P->cmap->N;
7141:     N          = P->cmap->N;
7142:     hasoffproc = PETSC_TRUE;
7143:     break;
7144:   default:
7145:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[ptype]);
7146:   }
7147:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)C), &size));
7148:   if (size == 1) hasoffproc = PETSC_FALSE;

7150:   /* defaults */
7151:   for (i = 0; i < MAX_NUMBER_INTERMEDIATE; i++) {
7152:     mp[i]    = NULL;
7153:     mptmp[i] = PETSC_FALSE;
7154:     rmapt[i] = -1;
7155:     cmapt[i] = -1;
7156:     rmapa[i] = NULL;
7157:     cmapa[i] = NULL;
7158:   }

7160:   /* customization */
7161:   PetscCall(PetscNew(&mmdata));
7162:   mmdata->reusesym = product->api_user;
7163:   if (ptype == MATPRODUCT_AB) {
7164:     if (product->api_user) {
7165:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatMatMult", "Mat");
7166:       PetscCall(PetscOptionsBool("-matmatmult_backend_mergeB", "Merge product->B local matrices", "MatMatMult", mmdata->abmerge, &mmdata->abmerge, NULL));
7167:       PetscCall(PetscOptionsBool("-matmatmult_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7168:       PetscOptionsEnd();
7169:     } else {
7170:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_AB", "Mat");
7171:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_mergeB", "Merge product->B local matrices", "MatMatMult", mmdata->abmerge, &mmdata->abmerge, NULL));
7172:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7173:       PetscOptionsEnd();
7174:     }
7175:   } else if (ptype == MATPRODUCT_PtAP) {
7176:     if (product->api_user) {
7177:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatPtAP", "Mat");
7178:       PetscCall(PetscOptionsBool("-matptap_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7179:       PetscOptionsEnd();
7180:     } else {
7181:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_PtAP", "Mat");
7182:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7183:       PetscOptionsEnd();
7184:     }
7185:   }
7186:   a = (Mat_MPIAIJ *)A->data;
7187:   p = (Mat_MPIAIJ *)P->data;
7188:   PetscCall(MatSetSizes(C, m, n, M, N));
7189:   PetscCall(PetscLayoutSetUp(C->rmap));
7190:   PetscCall(PetscLayoutSetUp(C->cmap));
7191:   PetscCall(MatSetType(C, ((PetscObject)A)->type_name));
7192:   PetscCall(MatGetOptionsPrefix(C, &prefix));

7194:   cp = 0;
7195:   switch (ptype) {
7196:   case MATPRODUCT_AB: /* A * P */
7197:     PetscCall(MatGetBrowsOfAoCols_MPIAIJ(A, P, MAT_INITIAL_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));

7199:     /* A_diag * P_local (merged or not) */
7200:     if (mmdata->abmerge) { /* P's diagonal and off-diag blocks are merged to one matrix, then multiplied by A_diag */
7201:       /* P is product->B */
7202:       PetscCall(MatMPIAIJGetLocalMatMerge(P, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7203:       PetscCall(MatProductCreate(a->A, mmdata->Bloc, NULL, &mp[cp]));
7204:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7205:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7206:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7207:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7208:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7209:       mp[cp]->product->api_user = product->api_user;
7210:       PetscCall(MatProductSetFromOptions(mp[cp]));
7211:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7212:       PetscCall(ISGetIndices(glob, &globidx));
7213:       rmapt[cp] = 1;
7214:       cmapt[cp] = 2;
7215:       cmapa[cp] = globidx;
7216:       mptmp[cp] = PETSC_FALSE;
7217:       cp++;
7218:     } else { /* A_diag * P_diag and A_diag * P_off */
7219:       PetscCall(MatProductCreate(a->A, p->A, NULL, &mp[cp]));
7220:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7221:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7222:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7223:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7224:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7225:       mp[cp]->product->api_user = product->api_user;
7226:       PetscCall(MatProductSetFromOptions(mp[cp]));
7227:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7228:       rmapt[cp] = 1;
7229:       cmapt[cp] = 1;
7230:       mptmp[cp] = PETSC_FALSE;
7231:       cp++;
7232:       PetscCall(MatProductCreate(a->A, p->B, NULL, &mp[cp]));
7233:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7234:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7235:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7236:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7237:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7238:       mp[cp]->product->api_user = product->api_user;
7239:       PetscCall(MatProductSetFromOptions(mp[cp]));
7240:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7241:       rmapt[cp] = 1;
7242:       cmapt[cp] = 2;
7243:       cmapa[cp] = p->garray;
7244:       mptmp[cp] = PETSC_FALSE;
7245:       cp++;
7246:     }

7248:     /* A_off * P_other */
7249:     if (mmdata->P_oth) {
7250:       PetscCall(MatSeqAIJCompactOutExtraColumns_SeqAIJ(mmdata->P_oth, &P_oth_l2g)); /* make P_oth use local col ids */
7251:       PetscCall(ISLocalToGlobalMappingGetIndices(P_oth_l2g, &P_oth_idx));
7252:       PetscCall(MatSetType(mmdata->P_oth, ((PetscObject)(a->B))->type_name));
7253:       PetscCall(MatBindToCPU(mmdata->P_oth, mmdata->P_oth_bind));
7254:       PetscCall(MatProductCreate(a->B, mmdata->P_oth, NULL, &mp[cp]));
7255:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7256:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7257:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7258:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7259:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7260:       mp[cp]->product->api_user = product->api_user;
7261:       PetscCall(MatProductSetFromOptions(mp[cp]));
7262:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7263:       rmapt[cp] = 1;
7264:       cmapt[cp] = 2;
7265:       cmapa[cp] = P_oth_idx;
7266:       mptmp[cp] = PETSC_FALSE;
7267:       cp++;
7268:     }
7269:     break;

7271:   case MATPRODUCT_AtB: /* (P^t * A): P_diag * A_loc + P_off * A_loc */
7272:     /* A is product->B */
7273:     PetscCall(MatMPIAIJGetLocalMatMerge(A, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7274:     if (A == P) { /* when A==P, we can take advantage of the already merged mmdata->Bloc */
7275:       PetscCall(MatProductCreate(mmdata->Bloc, mmdata->Bloc, NULL, &mp[cp]));
7276:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7277:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7278:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7279:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7280:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7281:       mp[cp]->product->api_user = product->api_user;
7282:       PetscCall(MatProductSetFromOptions(mp[cp]));
7283:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7284:       PetscCall(ISGetIndices(glob, &globidx));
7285:       rmapt[cp] = 2;
7286:       rmapa[cp] = globidx;
7287:       cmapt[cp] = 2;
7288:       cmapa[cp] = globidx;
7289:       mptmp[cp] = PETSC_FALSE;
7290:       cp++;
7291:     } else {
7292:       PetscCall(MatProductCreate(p->A, mmdata->Bloc, NULL, &mp[cp]));
7293:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7294:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7295:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7296:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7297:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7298:       mp[cp]->product->api_user = product->api_user;
7299:       PetscCall(MatProductSetFromOptions(mp[cp]));
7300:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7301:       PetscCall(ISGetIndices(glob, &globidx));
7302:       rmapt[cp] = 1;
7303:       cmapt[cp] = 2;
7304:       cmapa[cp] = globidx;
7305:       mptmp[cp] = PETSC_FALSE;
7306:       cp++;
7307:       PetscCall(MatProductCreate(p->B, mmdata->Bloc, NULL, &mp[cp]));
7308:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7309:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7310:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7311:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7312:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7313:       mp[cp]->product->api_user = product->api_user;
7314:       PetscCall(MatProductSetFromOptions(mp[cp]));
7315:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7316:       rmapt[cp] = 2;
7317:       rmapa[cp] = p->garray;
7318:       cmapt[cp] = 2;
7319:       cmapa[cp] = globidx;
7320:       mptmp[cp] = PETSC_FALSE;
7321:       cp++;
7322:     }
7323:     break;
7324:   case MATPRODUCT_PtAP:
7325:     PetscCall(MatGetBrowsOfAoCols_MPIAIJ(A, P, MAT_INITIAL_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));
7326:     /* P is product->B */
7327:     PetscCall(MatMPIAIJGetLocalMatMerge(P, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7328:     PetscCall(MatProductCreate(a->A, mmdata->Bloc, NULL, &mp[cp]));
7329:     PetscCall(MatProductSetType(mp[cp], MATPRODUCT_PtAP));
7330:     PetscCall(MatProductSetFill(mp[cp], product->fill));
7331:     PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7332:     PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7333:     PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7334:     mp[cp]->product->api_user = product->api_user;
7335:     PetscCall(MatProductSetFromOptions(mp[cp]));
7336:     PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7337:     PetscCall(ISGetIndices(glob, &globidx));
7338:     rmapt[cp] = 2;
7339:     rmapa[cp] = globidx;
7340:     cmapt[cp] = 2;
7341:     cmapa[cp] = globidx;
7342:     mptmp[cp] = PETSC_FALSE;
7343:     cp++;
7344:     if (mmdata->P_oth) {
7345:       PetscCall(MatSeqAIJCompactOutExtraColumns_SeqAIJ(mmdata->P_oth, &P_oth_l2g));
7346:       PetscCall(ISLocalToGlobalMappingGetIndices(P_oth_l2g, &P_oth_idx));
7347:       PetscCall(MatSetType(mmdata->P_oth, ((PetscObject)(a->B))->type_name));
7348:       PetscCall(MatBindToCPU(mmdata->P_oth, mmdata->P_oth_bind));
7349:       PetscCall(MatProductCreate(a->B, mmdata->P_oth, NULL, &mp[cp]));
7350:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7351:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7352:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7353:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7354:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7355:       mp[cp]->product->api_user = product->api_user;
7356:       PetscCall(MatProductSetFromOptions(mp[cp]));
7357:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7358:       mptmp[cp] = PETSC_TRUE;
7359:       cp++;
7360:       PetscCall(MatProductCreate(mmdata->Bloc, mp[1], NULL, &mp[cp]));
7361:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7362:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7363:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7364:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7365:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7366:       mp[cp]->product->api_user = product->api_user;
7367:       PetscCall(MatProductSetFromOptions(mp[cp]));
7368:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7369:       rmapt[cp] = 2;
7370:       rmapa[cp] = globidx;
7371:       cmapt[cp] = 2;
7372:       cmapa[cp] = P_oth_idx;
7373:       mptmp[cp] = PETSC_FALSE;
7374:       cp++;
7375:     }
7376:     break;
7377:   default:
7378:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[ptype]);
7379:   }
7380:   /* sanity check */
7381:   if (size > 1)
7382:     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);

7384:   PetscCall(PetscMalloc2(cp, &mmdata->mp, cp, &mmdata->mptmp));
7385:   for (i = 0; i < cp; i++) {
7386:     mmdata->mp[i]    = mp[i];
7387:     mmdata->mptmp[i] = mptmp[i];
7388:   }
7389:   mmdata->cp             = cp;
7390:   C->product->data       = mmdata;
7391:   C->product->destroy    = MatDestroy_MatMatMPIAIJBACKEND;
7392:   C->ops->productnumeric = MatProductNumeric_MPIAIJBACKEND;

7394:   /* memory type */
7395:   mmdata->mtype = PETSC_MEMTYPE_HOST;
7396:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iscuda, MATSEQAIJCUSPARSE, MATMPIAIJCUSPARSE, ""));
7397:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iship, MATSEQAIJHIPSPARSE, MATMPIAIJHIPSPARSE, ""));
7398:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iskokk, MATSEQAIJKOKKOS, MATMPIAIJKOKKOS, ""));
7399:   if (iscuda) mmdata->mtype = PETSC_MEMTYPE_CUDA;
7400:   else if (iship) mmdata->mtype = PETSC_MEMTYPE_HIP;
7401:   else if (iskokk) mmdata->mtype = PETSC_MEMTYPE_KOKKOS;

7403:   /* prepare coo coordinates for values insertion */

7405:   /* count total nonzeros of those intermediate seqaij Mats
7406:     ncoo_d:    # of nonzeros of matrices that do not have offproc entries
7407:     ncoo_o:    # of nonzeros (of matrices that might have offproc entries) that will be inserted to remote procs
7408:     ncoo_oown: # of nonzeros (of matrices that might have offproc entries) that will be inserted locally
7409:   */
7410:   for (cp = 0, ncoo_d = 0, ncoo_o = 0, ncoo_oown = 0; cp < mmdata->cp; cp++) {
7411:     Mat_SeqAIJ *mm = (Mat_SeqAIJ *)mp[cp]->data;
7412:     if (mptmp[cp]) continue;
7413:     if (rmapt[cp] == 2 && hasoffproc) { /* the rows need to be scatter to all processes (might include self) */
7414:       const PetscInt *rmap = rmapa[cp];
7415:       const PetscInt  mr   = mp[cp]->rmap->n;
7416:       const PetscInt  rs   = C->rmap->rstart;
7417:       const PetscInt  re   = C->rmap->rend;
7418:       const PetscInt *ii   = mm->i;
7419:       for (i = 0; i < mr; i++) {
7420:         const PetscInt gr = rmap[i];
7421:         const PetscInt nz = ii[i + 1] - ii[i];
7422:         if (gr < rs || gr >= re) ncoo_o += nz; /* this row is offproc */
7423:         else ncoo_oown += nz;                  /* this row is local */
7424:       }
7425:     } else ncoo_d += mm->nz;
7426:   }

7428:   /*
7429:     ncoo: total number of nonzeros (including those inserted by remote procs) belonging to this proc

7431:     ncoo = ncoo_d + ncoo_oown + ncoo2, which ncoo2 is number of nonzeros inserted to me by other procs.

7433:     off[0] points to a big index array, which is shared by off[1,2,...]. Similarly, for own[0].

7435:     off[p]: points to the segment for matrix mp[p], storing location of nonzeros that mp[p] will insert to others
7436:     own[p]: points to the segment for matrix mp[p], storing location of nonzeros that mp[p] will insert locally
7437:     so, off[p+1]-off[p] is the number of nonzeros that mp[p] will send to others.

7439:     coo_i/j/v[]: [ncoo] row/col/val of nonzeros belonging to this proc.
7440:     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.
7441:   */
7442:   PetscCall(PetscCalloc1(mmdata->cp + 1, &mmdata->off)); /* +1 to make a csr-like data structure */
7443:   PetscCall(PetscCalloc1(mmdata->cp + 1, &mmdata->own));

7445:   /* gather (i,j) of nonzeros inserted by remote procs */
7446:   if (hasoffproc) {
7447:     PetscSF  msf;
7448:     PetscInt ncoo2, *coo_i2, *coo_j2;

7450:     PetscCall(PetscMalloc1(ncoo_o, &mmdata->off[0]));
7451:     PetscCall(PetscMalloc1(ncoo_oown, &mmdata->own[0]));
7452:     PetscCall(PetscMalloc2(ncoo_o, &coo_i, ncoo_o, &coo_j)); /* to collect (i,j) of entries to be sent to others */

7454:     for (cp = 0, ncoo_o = 0; cp < mmdata->cp; cp++) {
7455:       Mat_SeqAIJ *mm     = (Mat_SeqAIJ *)mp[cp]->data;
7456:       PetscInt   *idxoff = mmdata->off[cp];
7457:       PetscInt   *idxown = mmdata->own[cp];
7458:       if (!mptmp[cp] && rmapt[cp] == 2) { /* row map is sparse */
7459:         const PetscInt *rmap = rmapa[cp];
7460:         const PetscInt *cmap = cmapa[cp];
7461:         const PetscInt *ii   = mm->i;
7462:         PetscInt       *coi  = coo_i + ncoo_o;
7463:         PetscInt       *coj  = coo_j + ncoo_o;
7464:         const PetscInt  mr   = mp[cp]->rmap->n;
7465:         const PetscInt  rs   = C->rmap->rstart;
7466:         const PetscInt  re   = C->rmap->rend;
7467:         const PetscInt  cs   = C->cmap->rstart;
7468:         for (i = 0; i < mr; i++) {
7469:           const PetscInt *jj = mm->j + ii[i];
7470:           const PetscInt  gr = rmap[i];
7471:           const PetscInt  nz = ii[i + 1] - ii[i];
7472:           if (gr < rs || gr >= re) { /* this is an offproc row */
7473:             for (j = ii[i]; j < ii[i + 1]; j++) {
7474:               *coi++    = gr;
7475:               *idxoff++ = j;
7476:             }
7477:             if (!cmapt[cp]) { /* already global */
7478:               for (j = 0; j < nz; j++) *coj++ = jj[j];
7479:             } else if (cmapt[cp] == 1) { /* local to global for owned columns of C */
7480:               for (j = 0; j < nz; j++) *coj++ = jj[j] + cs;
7481:             } else { /* offdiag */
7482:               for (j = 0; j < nz; j++) *coj++ = cmap[jj[j]];
7483:             }
7484:             ncoo_o += nz;
7485:           } else { /* this is a local row */
7486:             for (j = ii[i]; j < ii[i + 1]; j++) *idxown++ = j;
7487:           }
7488:         }
7489:       }
7490:       mmdata->off[cp + 1] = idxoff;
7491:       mmdata->own[cp + 1] = idxown;
7492:     }

7494:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)C), &mmdata->sf));
7495:     PetscCall(PetscSFSetGraphLayout(mmdata->sf, C->rmap, ncoo_o /*nleaves*/, NULL /*ilocal*/, PETSC_OWN_POINTER, coo_i));
7496:     PetscCall(PetscSFGetMultiSF(mmdata->sf, &msf));
7497:     PetscCall(PetscSFGetGraph(msf, &ncoo2 /*nroots*/, NULL, NULL, NULL));
7498:     ncoo = ncoo_d + ncoo_oown + ncoo2;
7499:     PetscCall(PetscMalloc2(ncoo, &coo_i2, ncoo, &coo_j2));
7500:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_INT, coo_i, coo_i2 + ncoo_d + ncoo_oown)); /* put (i,j) of remote nonzeros at back */
7501:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_INT, coo_i, coo_i2 + ncoo_d + ncoo_oown));
7502:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_INT, coo_j, coo_j2 + ncoo_d + ncoo_oown));
7503:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_INT, coo_j, coo_j2 + ncoo_d + ncoo_oown));
7504:     PetscCall(PetscFree2(coo_i, coo_j));
7505:     /* allocate MPI send buffer to collect nonzero values to be sent to remote procs */
7506:     PetscCall(PetscSFMalloc(mmdata->sf, mmdata->mtype, ncoo_o * sizeof(PetscScalar), (void **)&mmdata->coo_w));
7507:     coo_i = coo_i2;
7508:     coo_j = coo_j2;
7509:   } else { /* no offproc values insertion */
7510:     ncoo = ncoo_d;
7511:     PetscCall(PetscMalloc2(ncoo, &coo_i, ncoo, &coo_j));

7513:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)C), &mmdata->sf));
7514:     PetscCall(PetscSFSetGraph(mmdata->sf, 0, 0, NULL, PETSC_OWN_POINTER, NULL, PETSC_OWN_POINTER));
7515:     PetscCall(PetscSFSetUp(mmdata->sf));
7516:   }
7517:   mmdata->hasoffproc = hasoffproc;

7519:   /* gather (i,j) of nonzeros inserted locally */
7520:   for (cp = 0, ncoo_d = 0; cp < mmdata->cp; cp++) {
7521:     Mat_SeqAIJ     *mm   = (Mat_SeqAIJ *)mp[cp]->data;
7522:     PetscInt       *coi  = coo_i + ncoo_d;
7523:     PetscInt       *coj  = coo_j + ncoo_d;
7524:     const PetscInt *jj   = mm->j;
7525:     const PetscInt *ii   = mm->i;
7526:     const PetscInt *cmap = cmapa[cp];
7527:     const PetscInt *rmap = rmapa[cp];
7528:     const PetscInt  mr   = mp[cp]->rmap->n;
7529:     const PetscInt  rs   = C->rmap->rstart;
7530:     const PetscInt  re   = C->rmap->rend;
7531:     const PetscInt  cs   = C->cmap->rstart;

7533:     if (mptmp[cp]) continue;
7534:     if (rmapt[cp] == 1) { /* consecutive rows */
7535:       /* fill coo_i */
7536:       for (i = 0; i < mr; i++) {
7537:         const PetscInt gr = i + rs;
7538:         for (j = ii[i]; j < ii[i + 1]; j++) coi[j] = gr;
7539:       }
7540:       /* fill coo_j */
7541:       if (!cmapt[cp]) { /* type-0, already global */
7542:         PetscCall(PetscArraycpy(coj, jj, mm->nz));
7543:       } else if (cmapt[cp] == 1) {                        /* type-1, local to global for consecutive columns of C */
7544:         for (j = 0; j < mm->nz; j++) coj[j] = jj[j] + cs; /* lid + col start */
7545:       } else {                                            /* type-2, local to global for sparse columns */
7546:         for (j = 0; j < mm->nz; j++) coj[j] = cmap[jj[j]];
7547:       }
7548:       ncoo_d += mm->nz;
7549:     } else if (rmapt[cp] == 2) { /* sparse rows */
7550:       for (i = 0; i < mr; i++) {
7551:         const PetscInt *jj = mm->j + ii[i];
7552:         const PetscInt  gr = rmap[i];
7553:         const PetscInt  nz = ii[i + 1] - ii[i];
7554:         if (gr >= rs && gr < re) { /* local rows */
7555:           for (j = ii[i]; j < ii[i + 1]; j++) *coi++ = gr;
7556:           if (!cmapt[cp]) { /* type-0, already global */
7557:             for (j = 0; j < nz; j++) *coj++ = jj[j];
7558:           } else if (cmapt[cp] == 1) { /* local to global for owned columns of C */
7559:             for (j = 0; j < nz; j++) *coj++ = jj[j] + cs;
7560:           } else { /* type-2, local to global for sparse columns */
7561:             for (j = 0; j < nz; j++) *coj++ = cmap[jj[j]];
7562:           }
7563:           ncoo_d += nz;
7564:         }
7565:       }
7566:     }
7567:   }
7568:   if (glob) PetscCall(ISRestoreIndices(glob, &globidx));
7569:   PetscCall(ISDestroy(&glob));
7570:   if (P_oth_l2g) PetscCall(ISLocalToGlobalMappingRestoreIndices(P_oth_l2g, &P_oth_idx));
7571:   PetscCall(ISLocalToGlobalMappingDestroy(&P_oth_l2g));
7572:   /* allocate an array to store all nonzeros (inserted locally or remotely) belonging to this proc */
7573:   PetscCall(PetscSFMalloc(mmdata->sf, mmdata->mtype, ncoo * sizeof(PetscScalar), (void **)&mmdata->coo_v));

7575:   /* preallocate with COO data */
7576:   PetscCall(MatSetPreallocationCOO(C, ncoo, coo_i, coo_j));
7577:   PetscCall(PetscFree2(coo_i, coo_j));
7578:   PetscFunctionReturn(PETSC_SUCCESS);
7579: }

7581: PetscErrorCode MatProductSetFromOptions_MPIAIJBACKEND(Mat mat)
7582: {
7583:   Mat_Product *product = mat->product;
7584: #if defined(PETSC_HAVE_DEVICE)
7585:   PetscBool match  = PETSC_FALSE;
7586:   PetscBool usecpu = PETSC_FALSE;
7587: #else
7588:   PetscBool match = PETSC_TRUE;
7589: #endif

7591:   PetscFunctionBegin;
7592:   MatCheckProduct(mat, 1);
7593: #if defined(PETSC_HAVE_DEVICE)
7594:   if (!product->A->boundtocpu && !product->B->boundtocpu) PetscCall(PetscObjectTypeCompare((PetscObject)product->B, ((PetscObject)product->A)->type_name, &match));
7595:   if (match) { /* we can always fallback to the CPU if requested */
7596:     switch (product->type) {
7597:     case MATPRODUCT_AB:
7598:       if (product->api_user) {
7599:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatMatMult", "Mat");
7600:         PetscCall(PetscOptionsBool("-matmatmult_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
7601:         PetscOptionsEnd();
7602:       } else {
7603:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AB", "Mat");
7604:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
7605:         PetscOptionsEnd();
7606:       }
7607:       break;
7608:     case MATPRODUCT_AtB:
7609:       if (product->api_user) {
7610:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatTransposeMatMult", "Mat");
7611:         PetscCall(PetscOptionsBool("-mattransposematmult_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
7612:         PetscOptionsEnd();
7613:       } else {
7614:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AtB", "Mat");
7615:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
7616:         PetscOptionsEnd();
7617:       }
7618:       break;
7619:     case MATPRODUCT_PtAP:
7620:       if (product->api_user) {
7621:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatPtAP", "Mat");
7622:         PetscCall(PetscOptionsBool("-matptap_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
7623:         PetscOptionsEnd();
7624:       } else {
7625:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_PtAP", "Mat");
7626:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
7627:         PetscOptionsEnd();
7628:       }
7629:       break;
7630:     default:
7631:       break;
7632:     }
7633:     match = (PetscBool)!usecpu;
7634:   }
7635: #endif
7636:   if (match) {
7637:     switch (product->type) {
7638:     case MATPRODUCT_AB:
7639:     case MATPRODUCT_AtB:
7640:     case MATPRODUCT_PtAP:
7641:       mat->ops->productsymbolic = MatProductSymbolic_MPIAIJBACKEND;
7642:       break;
7643:     default:
7644:       break;
7645:     }
7646:   }
7647:   /* fallback to MPIAIJ ops */
7648:   if (!mat->ops->productsymbolic) PetscCall(MatProductSetFromOptions_MPIAIJ(mat));
7649:   PetscFunctionReturn(PETSC_SUCCESS);
7650: }

7652: /*
7653:    Produces a set of block column indices of the matrix row, one for each block represented in the original row

7655:    n - the number of block indices in cc[]
7656:    cc - the block indices (must be large enough to contain the indices)
7657: */
7658: static inline PetscErrorCode MatCollapseRow(Mat Amat, PetscInt row, PetscInt bs, PetscInt *n, PetscInt *cc)
7659: {
7660:   PetscInt        cnt = -1, nidx, j;
7661:   const PetscInt *idx;

7663:   PetscFunctionBegin;
7664:   PetscCall(MatGetRow(Amat, row, &nidx, &idx, NULL));
7665:   if (nidx) {
7666:     cnt     = 0;
7667:     cc[cnt] = idx[0] / bs;
7668:     for (j = 1; j < nidx; j++) {
7669:       if (cc[cnt] < idx[j] / bs) cc[++cnt] = idx[j] / bs;
7670:     }
7671:   }
7672:   PetscCall(MatRestoreRow(Amat, row, &nidx, &idx, NULL));
7673:   *n = cnt + 1;
7674:   PetscFunctionReturn(PETSC_SUCCESS);
7675: }

7677: /*
7678:     Produces a set of block column indices of the matrix block row, one for each block represented in the original set of rows

7680:     ncollapsed - the number of block indices
7681:     collapsed - the block indices (must be large enough to contain the indices)
7682: */
7683: static inline PetscErrorCode MatCollapseRows(Mat Amat, PetscInt start, PetscInt bs, PetscInt *w0, PetscInt *w1, PetscInt *w2, PetscInt *ncollapsed, PetscInt **collapsed)
7684: {
7685:   PetscInt i, nprev, *cprev = w0, ncur = 0, *ccur = w1, *merged = w2, *cprevtmp;

7687:   PetscFunctionBegin;
7688:   PetscCall(MatCollapseRow(Amat, start, bs, &nprev, cprev));
7689:   for (i = start + 1; i < start + bs; i++) {
7690:     PetscCall(MatCollapseRow(Amat, i, bs, &ncur, ccur));
7691:     PetscCall(PetscMergeIntArray(nprev, cprev, ncur, ccur, &nprev, &merged));
7692:     cprevtmp = cprev;
7693:     cprev    = merged;
7694:     merged   = cprevtmp;
7695:   }
7696:   *ncollapsed = nprev;
7697:   if (collapsed) *collapsed = cprev;
7698:   PetscFunctionReturn(PETSC_SUCCESS);
7699: }

7701: /*
7702:  MatCreateGraph_Simple_AIJ - create simple scalar matrix (graph) from potentially blocked matrix

7704:  Input Parameter:
7705:  . Amat - matrix
7706:  - symmetrize - make the result symmetric
7707:  + scale - scale with diagonal

7709:  Output Parameter:
7710:  . a_Gmat - output scalar graph >= 0

7712: */
7713: PETSC_INTERN PetscErrorCode MatCreateGraph_Simple_AIJ(Mat Amat, PetscBool symmetrize, PetscBool scale, PetscReal filter, Mat *a_Gmat)
7714: {
7715:   PetscInt  Istart, Iend, Ii, jj, kk, ncols, nloc, NN, MM, bs;
7716:   MPI_Comm  comm;
7717:   Mat       Gmat;
7718:   PetscBool ismpiaij, isseqaij;
7719:   Mat       a, b, c;
7720:   MatType   jtype;

7722:   PetscFunctionBegin;
7723:   PetscCall(PetscObjectGetComm((PetscObject)Amat, &comm));
7724:   PetscCall(MatGetOwnershipRange(Amat, &Istart, &Iend));
7725:   PetscCall(MatGetSize(Amat, &MM, &NN));
7726:   PetscCall(MatGetBlockSize(Amat, &bs));
7727:   nloc = (Iend - Istart) / bs;

7729:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)Amat, MATSEQAIJ, &isseqaij));
7730:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)Amat, MATMPIAIJ, &ismpiaij));
7731:   PetscCheck(isseqaij || ismpiaij, comm, PETSC_ERR_USER, "Require (MPI)AIJ matrix type");

7733:   /* TODO GPU: these calls are potentially expensive if matrices are large and we want to use the GPU */
7734:   /* A solution consists in providing a new API, MatAIJGetCollapsedAIJ, and each class can provide a fast
7735:      implementation */
7736:   if (bs > 1) {
7737:     PetscCall(MatGetType(Amat, &jtype));
7738:     PetscCall(MatCreate(comm, &Gmat));
7739:     PetscCall(MatSetType(Gmat, jtype));
7740:     PetscCall(MatSetSizes(Gmat, nloc, nloc, PETSC_DETERMINE, PETSC_DETERMINE));
7741:     PetscCall(MatSetBlockSizes(Gmat, 1, 1));
7742:     if (isseqaij || ((Mat_MPIAIJ *)Amat->data)->garray) {
7743:       PetscInt  *d_nnz, *o_nnz;
7744:       MatScalar *aa, val, *AA;
7745:       PetscInt  *aj, *ai, *AJ, nc, nmax = 0;
7746:       if (isseqaij) {
7747:         a = Amat;
7748:         b = NULL;
7749:       } else {
7750:         Mat_MPIAIJ *d = (Mat_MPIAIJ *)Amat->data;
7751:         a             = d->A;
7752:         b             = d->B;
7753:       }
7754:       PetscCall(PetscInfo(Amat, "New bs>1 Graph. nloc=%" PetscInt_FMT "\n", nloc));
7755:       PetscCall(PetscMalloc2(nloc, &d_nnz, isseqaij ? 0 : nloc, &o_nnz));
7756:       for (c = a, kk = 0; c && kk < 2; c = b, kk++) {
7757:         PetscInt       *nnz = (c == a) ? d_nnz : o_nnz;
7758:         const PetscInt *cols1, *cols2;
7759:         for (PetscInt brow = 0, nc1, nc2, ok = 1; brow < nloc * bs; brow += bs) { // block rows
7760:           PetscCall(MatGetRow(c, brow, &nc2, &cols2, NULL));
7761:           nnz[brow / bs] = nc2 / bs;
7762:           if (nc2 % bs) ok = 0;
7763:           if (nnz[brow / bs] > nmax) nmax = nnz[brow / bs];
7764:           for (PetscInt ii = 1; ii < bs; ii++) { // check for non-dense blocks
7765:             PetscCall(MatGetRow(c, brow + ii, &nc1, &cols1, NULL));
7766:             if (nc1 != nc2) ok = 0;
7767:             else {
7768:               for (PetscInt jj = 0; jj < nc1 && ok == 1; jj++) {
7769:                 if (cols1[jj] != cols2[jj]) ok = 0;
7770:                 if (cols1[jj] % bs != jj % bs) ok = 0;
7771:               }
7772:             }
7773:             PetscCall(MatRestoreRow(c, brow + ii, &nc1, &cols1, NULL));
7774:           }
7775:           PetscCall(MatRestoreRow(c, brow, &nc2, &cols2, NULL));
7776:           if (!ok) {
7777:             PetscCall(PetscFree2(d_nnz, o_nnz));
7778:             PetscCall(PetscInfo(Amat, "Found sparse blocks - revert to slow method\n"));
7779:             goto old_bs;
7780:           }
7781:         }
7782:       }
7783:       PetscCall(MatSeqAIJSetPreallocation(Gmat, 0, d_nnz));
7784:       PetscCall(MatMPIAIJSetPreallocation(Gmat, 0, d_nnz, 0, o_nnz));
7785:       PetscCall(PetscFree2(d_nnz, o_nnz));
7786:       PetscCall(PetscMalloc2(nmax, &AA, nmax, &AJ));
7787:       // diag
7788:       for (PetscInt brow = 0, n, grow; brow < nloc * bs; brow += bs) { // block rows
7789:         Mat_SeqAIJ *aseq = (Mat_SeqAIJ *)a->data;
7790:         ai               = aseq->i;
7791:         n                = ai[brow + 1] - ai[brow];
7792:         aj               = aseq->j + ai[brow];
7793:         for (int k = 0; k < n; k += bs) {        // block columns
7794:           AJ[k / bs] = aj[k] / bs + Istart / bs; // diag starts at (Istart,Istart)
7795:           val        = 0;
7796:           for (int ii = 0; ii < bs; ii++) { // rows in block
7797:             aa = aseq->a + ai[brow + ii] + k;
7798:             for (int jj = 0; jj < bs; jj++) {         // columns in block
7799:               val += PetscAbs(PetscRealPart(aa[jj])); // a sort of norm
7800:             }
7801:           }
7802:           PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs (%d) >= nmax (%d)", (int)(k / bs), (int)nmax);
7803:           AA[k / bs] = val;
7804:         }
7805:         grow = Istart / bs + brow / bs;
7806:         PetscCall(MatSetValues(Gmat, 1, &grow, n / bs, AJ, AA, INSERT_VALUES));
7807:       }
7808:       // off-diag
7809:       if (ismpiaij) {
7810:         Mat_MPIAIJ        *aij = (Mat_MPIAIJ *)Amat->data;
7811:         const PetscScalar *vals;
7812:         const PetscInt    *cols, *garray = aij->garray;
7813:         PetscCheck(garray, PETSC_COMM_SELF, PETSC_ERR_USER, "No garray ?");
7814:         for (PetscInt brow = 0, grow; brow < nloc * bs; brow += bs) { // block rows
7815:           PetscCall(MatGetRow(b, brow, &ncols, &cols, NULL));
7816:           for (int k = 0, cidx = 0; k < ncols; k += bs, cidx++) {
7817:             PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs >= nmax");
7818:             AA[k / bs] = 0;
7819:             AJ[cidx]   = garray[cols[k]] / bs;
7820:           }
7821:           nc = ncols / bs;
7822:           PetscCall(MatRestoreRow(b, brow, &ncols, &cols, NULL));
7823:           for (int ii = 0; ii < bs; ii++) { // rows in block
7824:             PetscCall(MatGetRow(b, brow + ii, &ncols, &cols, &vals));
7825:             for (int k = 0; k < ncols; k += bs) {
7826:               for (int jj = 0; jj < bs; jj++) { // cols in block
7827:                 PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs (%d) >= nmax (%d)", (int)(k / bs), (int)nmax);
7828:                 AA[k / bs] += PetscAbs(PetscRealPart(vals[k + jj]));
7829:               }
7830:             }
7831:             PetscCall(MatRestoreRow(b, brow + ii, &ncols, &cols, &vals));
7832:           }
7833:           grow = Istart / bs + brow / bs;
7834:           PetscCall(MatSetValues(Gmat, 1, &grow, nc, AJ, AA, INSERT_VALUES));
7835:         }
7836:       }
7837:       PetscCall(MatAssemblyBegin(Gmat, MAT_FINAL_ASSEMBLY));
7838:       PetscCall(MatAssemblyEnd(Gmat, MAT_FINAL_ASSEMBLY));
7839:       PetscCall(PetscFree2(AA, AJ));
7840:     } else {
7841:       const PetscScalar *vals;
7842:       const PetscInt    *idx;
7843:       PetscInt          *d_nnz, *o_nnz, *w0, *w1, *w2;
7844:     old_bs:
7845:       /*
7846:        Determine the preallocation needed for the scalar matrix derived from the vector matrix.
7847:        */
7848:       PetscCall(PetscInfo(Amat, "OLD bs>1 CreateGraph\n"));
7849:       PetscCall(PetscMalloc2(nloc, &d_nnz, isseqaij ? 0 : nloc, &o_nnz));
7850:       if (isseqaij) {
7851:         PetscInt max_d_nnz;
7852:         /*
7853:          Determine exact preallocation count for (sequential) scalar matrix
7854:          */
7855:         PetscCall(MatSeqAIJGetMaxRowNonzeros(Amat, &max_d_nnz));
7856:         max_d_nnz = PetscMin(nloc, bs * max_d_nnz);
7857:         PetscCall(PetscMalloc3(max_d_nnz, &w0, max_d_nnz, &w1, max_d_nnz, &w2));
7858:         for (Ii = 0, jj = 0; Ii < Iend; Ii += bs, jj++) PetscCall(MatCollapseRows(Amat, Ii, bs, w0, w1, w2, &d_nnz[jj], NULL));
7859:         PetscCall(PetscFree3(w0, w1, w2));
7860:       } else if (ismpiaij) {
7861:         Mat             Daij, Oaij;
7862:         const PetscInt *garray;
7863:         PetscInt        max_d_nnz;
7864:         PetscCall(MatMPIAIJGetSeqAIJ(Amat, &Daij, &Oaij, &garray));
7865:         /*
7866:          Determine exact preallocation count for diagonal block portion of scalar matrix
7867:          */
7868:         PetscCall(MatSeqAIJGetMaxRowNonzeros(Daij, &max_d_nnz));
7869:         max_d_nnz = PetscMin(nloc, bs * max_d_nnz);
7870:         PetscCall(PetscMalloc3(max_d_nnz, &w0, max_d_nnz, &w1, max_d_nnz, &w2));
7871:         for (Ii = 0, jj = 0; Ii < Iend - Istart; Ii += bs, jj++) PetscCall(MatCollapseRows(Daij, Ii, bs, w0, w1, w2, &d_nnz[jj], NULL));
7872:         PetscCall(PetscFree3(w0, w1, w2));
7873:         /*
7874:          Over estimate (usually grossly over), preallocation count for off-diagonal portion of scalar matrix
7875:          */
7876:         for (Ii = 0, jj = 0; Ii < Iend - Istart; Ii += bs, jj++) {
7877:           o_nnz[jj] = 0;
7878:           for (kk = 0; kk < bs; kk++) { /* rows that get collapsed to a single row */
7879:             PetscCall(MatGetRow(Oaij, Ii + kk, &ncols, NULL, NULL));
7880:             o_nnz[jj] += ncols;
7881:             PetscCall(MatRestoreRow(Oaij, Ii + kk, &ncols, NULL, NULL));
7882:           }
7883:           if (o_nnz[jj] > (NN / bs - nloc)) o_nnz[jj] = NN / bs - nloc;
7884:         }
7885:       } else SETERRQ(comm, PETSC_ERR_USER, "Require AIJ matrix type");
7886:       /* get scalar copy (norms) of matrix */
7887:       PetscCall(MatSeqAIJSetPreallocation(Gmat, 0, d_nnz));
7888:       PetscCall(MatMPIAIJSetPreallocation(Gmat, 0, d_nnz, 0, o_nnz));
7889:       PetscCall(PetscFree2(d_nnz, o_nnz));
7890:       for (Ii = Istart; Ii < Iend; Ii++) {
7891:         PetscInt dest_row = Ii / bs;
7892:         PetscCall(MatGetRow(Amat, Ii, &ncols, &idx, &vals));
7893:         for (jj = 0; jj < ncols; jj++) {
7894:           PetscInt    dest_col = idx[jj] / bs;
7895:           PetscScalar sv       = PetscAbs(PetscRealPart(vals[jj]));
7896:           PetscCall(MatSetValues(Gmat, 1, &dest_row, 1, &dest_col, &sv, ADD_VALUES));
7897:         }
7898:         PetscCall(MatRestoreRow(Amat, Ii, &ncols, &idx, &vals));
7899:       }
7900:       PetscCall(MatAssemblyBegin(Gmat, MAT_FINAL_ASSEMBLY));
7901:       PetscCall(MatAssemblyEnd(Gmat, MAT_FINAL_ASSEMBLY));
7902:     }
7903:   } else {
7904:     if (symmetrize || filter >= 0 || scale) PetscCall(MatDuplicate(Amat, MAT_COPY_VALUES, &Gmat));
7905:     else {
7906:       Gmat = Amat;
7907:       PetscCall(PetscObjectReference((PetscObject)Gmat));
7908:     }
7909:     if (isseqaij) {
7910:       a = Gmat;
7911:       b = NULL;
7912:     } else {
7913:       Mat_MPIAIJ *d = (Mat_MPIAIJ *)Gmat->data;
7914:       a             = d->A;
7915:       b             = d->B;
7916:     }
7917:     if (filter >= 0 || scale) {
7918:       /* take absolute value of each entry */
7919:       for (c = a, kk = 0; c && kk < 2; c = b, kk++) {
7920:         MatInfo      info;
7921:         PetscScalar *avals;
7922:         PetscCall(MatGetInfo(c, MAT_LOCAL, &info));
7923:         PetscCall(MatSeqAIJGetArray(c, &avals));
7924:         for (int jj = 0; jj < info.nz_used; jj++) avals[jj] = PetscAbsScalar(avals[jj]);
7925:         PetscCall(MatSeqAIJRestoreArray(c, &avals));
7926:       }
7927:     }
7928:   }
7929:   if (symmetrize) {
7930:     PetscBool isset, issym;
7931:     PetscCall(MatIsSymmetricKnown(Amat, &isset, &issym));
7932:     if (!isset || !issym) {
7933:       Mat matTrans;
7934:       PetscCall(MatTranspose(Gmat, MAT_INITIAL_MATRIX, &matTrans));
7935:       PetscCall(MatAXPY(Gmat, 1.0, matTrans, Gmat->structurally_symmetric == PETSC_BOOL3_TRUE ? SAME_NONZERO_PATTERN : DIFFERENT_NONZERO_PATTERN));
7936:       PetscCall(MatDestroy(&matTrans));
7937:     }
7938:     PetscCall(MatSetOption(Gmat, MAT_SYMMETRIC, PETSC_TRUE));
7939:   } else if (Amat != Gmat) PetscCall(MatPropagateSymmetryOptions(Amat, Gmat));
7940:   if (scale) {
7941:     /* scale c for all diagonal values = 1 or -1 */
7942:     Vec diag;
7943:     PetscCall(MatCreateVecs(Gmat, &diag, NULL));
7944:     PetscCall(MatGetDiagonal(Gmat, diag));
7945:     PetscCall(VecReciprocal(diag));
7946:     PetscCall(VecSqrtAbs(diag));
7947:     PetscCall(MatDiagonalScale(Gmat, diag, diag));
7948:     PetscCall(VecDestroy(&diag));
7949:   }
7950:   PetscCall(MatViewFromOptions(Gmat, NULL, "-mat_graph_view"));

7952:   if (filter >= 0) {
7953:     PetscCall(MatFilter(Gmat, filter, PETSC_TRUE, PETSC_TRUE));
7954:     PetscCall(MatViewFromOptions(Gmat, NULL, "-mat_filter_graph_view"));
7955:   }
7956:   *a_Gmat = Gmat;
7957:   PetscFunctionReturn(PETSC_SUCCESS);
7958: }

7960: /*
7961:     Special version for direct calls from Fortran
7962: */
7963: #include <petsc/private/fortranimpl.h>

7965: /* Change these macros so can be used in void function */
7966: /* Identical to PetscCallVoid, except it assigns to *_ierr */
7967: #undef PetscCall
7968: #define PetscCall(...) \
7969:   do { \
7970:     PetscErrorCode ierr_msv_mpiaij = __VA_ARGS__; \
7971:     if (PetscUnlikely(ierr_msv_mpiaij)) { \
7972:       *_ierr = PetscError(PETSC_COMM_SELF, __LINE__, PETSC_FUNCTION_NAME, __FILE__, ierr_msv_mpiaij, PETSC_ERROR_REPEAT, " "); \
7973:       return; \
7974:     } \
7975:   } while (0)

7977: #undef SETERRQ
7978: #define SETERRQ(comm, ierr, ...) \
7979:   do { \
7980:     *_ierr = PetscError(comm, __LINE__, PETSC_FUNCTION_NAME, __FILE__, ierr, PETSC_ERROR_INITIAL, __VA_ARGS__); \
7981:     return; \
7982:   } while (0)

7984: #if defined(PETSC_HAVE_FORTRAN_CAPS)
7985:   #define matsetvaluesmpiaij_ MATSETVALUESMPIAIJ
7986: #elif !defined(PETSC_HAVE_FORTRAN_UNDERSCORE)
7987:   #define matsetvaluesmpiaij_ matsetvaluesmpiaij