xref: /petsc/src/mat/impls/aij/seq/matrart.c (revision 287c2655d648353bfb2fc9b0abbaccecc8a8143c)
1 
2 /*
3   Defines projective product routines where A is a SeqAIJ matrix
4           C = R * A * R^T
5 */
6 
7 #include <../src/mat/impls/aij/seq/aij.h>
8 #include <../src/mat/utils/freespace.h>
9 #include <../src/mat/impls/dense/seq/dense.h> /*I "petscmat.h" I*/
10 
11 PetscErrorCode MatDestroy_SeqAIJ_RARt(Mat A)
12 {
13   PetscErrorCode ierr;
14   Mat_SeqAIJ     *a    = (Mat_SeqAIJ*)A->data;
15   Mat_RARt       *rart = a->rart;
16 
17   PetscFunctionBegin;
18   ierr = MatTransposeColoringDestroy(&rart->matcoloring);CHKERRQ(ierr);
19   ierr = MatDestroy(&rart->Rt);CHKERRQ(ierr);
20   ierr = MatDestroy(&rart->RARt);CHKERRQ(ierr);
21   ierr = MatDestroy(&rart->ARt);CHKERRQ(ierr);
22   ierr = PetscFree(rart->work);CHKERRQ(ierr);
23 
24   A->ops->destroy = rart->destroy;
25   if (A->ops->destroy) {
26     ierr = (*A->ops->destroy)(A);CHKERRQ(ierr);
27   }
28   ierr = PetscFree(rart);CHKERRQ(ierr);
29   PetscFunctionReturn(0);
30 }
31 
32 PetscErrorCode MatRARtSymbolic_SeqAIJ_SeqAIJ_colorrart(Mat A,Mat R,PetscReal fill,Mat *C)
33 {
34   PetscErrorCode       ierr;
35   Mat                  P;
36   PetscInt             *rti,*rtj;
37   Mat_RARt             *rart;
38   MatColoring          coloring;
39   MatTransposeColoring matcoloring;
40   ISColoring           iscoloring;
41   Mat                  Rt_dense,RARt_dense;
42   Mat_SeqAIJ           *c;
43 
44   PetscFunctionBegin;
45   /* create symbolic P=Rt */
46   ierr = MatGetSymbolicTranspose_SeqAIJ(R,&rti,&rtj);CHKERRQ(ierr);
47   ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,R->cmap->n,R->rmap->n,rti,rtj,NULL,&P);CHKERRQ(ierr);
48 
49   /* get symbolic C=Pt*A*P */
50   ierr = MatPtAPSymbolic_SeqAIJ_SeqAIJ_SparseAxpy(A,P,fill,C);CHKERRQ(ierr);
51   ierr = MatSetBlockSizes(*C,PetscAbs(R->rmap->bs),PetscAbs(R->rmap->bs));CHKERRQ(ierr);
52   (*C)->ops->rartnumeric = MatRARtNumeric_SeqAIJ_SeqAIJ_colorrart;
53 
54   /* create a supporting struct */
55   ierr    = PetscNew(&rart);CHKERRQ(ierr);
56   c       = (Mat_SeqAIJ*)(*C)->data;
57   c->rart = rart;
58 
59   /* ------ Use coloring ---------- */
60   /* inode causes memory problem, don't know why */
61   if (c->inode.use) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"MAT_USE_INODES is not supported. Use '-mat_no_inode'");
62 
63   /* Create MatTransposeColoring from symbolic C=R*A*R^T */
64   ierr = MatColoringCreate(*C,&coloring);CHKERRQ(ierr);
65   ierr = MatColoringSetDistance(coloring,2);CHKERRQ(ierr);
66   ierr = MatColoringSetType(coloring,MATCOLORINGSL);CHKERRQ(ierr);
67   ierr = MatColoringSetFromOptions(coloring);CHKERRQ(ierr);
68   ierr = MatColoringApply(coloring,&iscoloring);CHKERRQ(ierr);
69   ierr = MatColoringDestroy(&coloring);CHKERRQ(ierr);
70   ierr = MatTransposeColoringCreate(*C,iscoloring,&matcoloring);CHKERRQ(ierr);
71 
72   rart->matcoloring = matcoloring;
73   ierr = ISColoringDestroy(&iscoloring);CHKERRQ(ierr);
74 
75   /* Create Rt_dense */
76   ierr = MatCreate(PETSC_COMM_SELF,&Rt_dense);CHKERRQ(ierr);
77   ierr = MatSetSizes(Rt_dense,A->cmap->n,matcoloring->ncolors,A->cmap->n,matcoloring->ncolors);CHKERRQ(ierr);
78   ierr = MatSetType(Rt_dense,MATSEQDENSE);CHKERRQ(ierr);
79   ierr = MatSeqDenseSetPreallocation(Rt_dense,NULL);CHKERRQ(ierr);
80 
81   Rt_dense->assembled = PETSC_TRUE;
82   rart->Rt            = Rt_dense;
83 
84   /* Create RARt_dense = R*A*Rt_dense */
85   ierr = MatCreate(PETSC_COMM_SELF,&RARt_dense);CHKERRQ(ierr);
86   ierr = MatSetSizes(RARt_dense,(*C)->rmap->n,matcoloring->ncolors,(*C)->rmap->n,matcoloring->ncolors);CHKERRQ(ierr);
87   ierr = MatSetType(RARt_dense,MATSEQDENSE);CHKERRQ(ierr);
88   ierr = MatSeqDenseSetPreallocation(RARt_dense,NULL);CHKERRQ(ierr);
89 
90   rart->RARt = RARt_dense;
91 
92   /* Allocate work array to store columns of A*R^T used in MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense() */
93   ierr = PetscMalloc1(A->rmap->n*4,&rart->work);CHKERRQ(ierr);
94 
95   rart->destroy      = (*C)->ops->destroy;
96   (*C)->ops->destroy = MatDestroy_SeqAIJ_RARt;
97 
98   /* clean up */
99   ierr = MatRestoreSymbolicTranspose_SeqAIJ(R,&rti,&rtj);CHKERRQ(ierr);
100   ierr = MatDestroy(&P);CHKERRQ(ierr);
101 
102 #if defined(PETSC_USE_INFO)
103   {
104     PetscReal density= (PetscReal)(c->nz)/(RARt_dense->rmap->n*RARt_dense->cmap->n);
105     ierr = PetscInfo(*C,"C=R*(A*Rt) via coloring C - use sparse-dense inner products\n");CHKERRQ(ierr);
106     ierr = PetscInfo6(*C,"RARt_den %D %D; Rt %D %D (RARt->nz %D)/(m*ncolors)=%g\n",RARt_dense->rmap->n,RARt_dense->cmap->n,R->cmap->n,R->rmap->n,c->nz,density);CHKERRQ(ierr);
107   }
108 #endif
109   PetscFunctionReturn(0);
110 }
111 
112 /*
113  RAB = R * A * B, R and A in seqaij format, B in dense format;
114 */
115 PetscErrorCode MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense(Mat R,Mat A,Mat B,Mat RAB,PetscScalar *work)
116 {
117   Mat_SeqAIJ     *a=(Mat_SeqAIJ*)A->data,*r=(Mat_SeqAIJ*)R->data;
118   PetscErrorCode ierr;
119   PetscScalar    *b,r1,r2,r3,r4,*b1,*b2,*b3,*b4;
120   MatScalar      *aa,*ra;
121   PetscInt       cn =B->cmap->n,bm=B->rmap->n,col,i,j,n,*ai=a->i,*aj,am=A->rmap->n;
122   PetscInt       am2=2*am,am3=3*am,bm4=4*bm;
123   PetscScalar    *d,*c,*c2,*c3,*c4;
124   PetscInt       *rj,rm=R->rmap->n,dm=RAB->rmap->n,dn=RAB->cmap->n;
125   PetscInt       rm2=2*rm,rm3=3*rm,colrm;
126 
127   PetscFunctionBegin;
128   if (!dm || !dn) PetscFunctionReturn(0);
129   if (bm != A->cmap->n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Number columns in A %D not equal rows in B %D\n",A->cmap->n,bm);
130   if (am != R->cmap->n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Number columns in R %D not equal rows in A %D\n",R->cmap->n,am);
131   if (R->rmap->n != RAB->rmap->n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Number rows in RAB %D not equal rows in R %D\n",RAB->rmap->n,R->rmap->n);
132   if (B->cmap->n != RAB->cmap->n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Number columns in RAB %D not equal columns in B %D\n",RAB->cmap->n,B->cmap->n);
133 
134   { /*
135      This approach is not as good as original ones (will be removed later), but it reveals that
136      AB_den=A*B takes almost all execution time in R*A*B for src/ksp/ksp/examples/tutorials/ex56.c
137      */
138     PetscBool via_matmatmult=PETSC_FALSE;
139     ierr = PetscOptionsGetBool(NULL,NULL,"-matrart_via_matmatmult",&via_matmatmult,NULL);CHKERRQ(ierr);
140     if (via_matmatmult) {
141       Mat AB_den;
142       ierr = MatMatMultSymbolic_SeqAIJ_SeqDense(A,B,0.0,&AB_den);CHKERRQ(ierr);
143       ierr = MatMatMultNumeric_SeqAIJ_SeqDense(A,B,AB_den);CHKERRQ(ierr);
144       ierr = MatMatMultNumeric_SeqAIJ_SeqDense(R,AB_den,RAB);CHKERRQ(ierr);
145       ierr = MatDestroy(&AB_den);CHKERRQ(ierr);
146       PetscFunctionReturn(0);
147     }
148   }
149 
150   ierr = MatDenseGetArray(B,&b);CHKERRQ(ierr);
151   ierr = MatDenseGetArray(RAB,&d);CHKERRQ(ierr);
152   b1   = b; b2 = b1 + bm; b3 = b2 + bm; b4 = b3 + bm;
153   c    = work; c2 = c + am; c3 = c2 + am; c4 = c3 + am;
154   for (col=0; col<cn-4; col += 4) {  /* over columns of C */
155     for (i=0; i<am; i++) {        /* over rows of A in those columns */
156       r1 = r2 = r3 = r4 = 0.0;
157       n  = ai[i+1] - ai[i];
158       aj = a->j + ai[i];
159       aa = a->a + ai[i];
160       for (j=0; j<n; j++) {
161         r1 += (*aa)*b1[*aj];
162         r2 += (*aa)*b2[*aj];
163         r3 += (*aa)*b3[*aj];
164         r4 += (*aa++)*b4[*aj++];
165       }
166       c[i]       = r1;
167       c[am  + i] = r2;
168       c[am2 + i] = r3;
169       c[am3 + i] = r4;
170     }
171     b1 += bm4;
172     b2 += bm4;
173     b3 += bm4;
174     b4 += bm4;
175 
176     /* RAB[:,col] = R*C[:,col] */
177     colrm = col*rm;
178     for (i=0; i<rm; i++) {        /* over rows of R in those columns */
179       r1 = r2 = r3 = r4 = 0.0;
180       n  = r->i[i+1] - r->i[i];
181       rj = r->j + r->i[i];
182       ra = r->a + r->i[i];
183       for (j=0; j<n; j++) {
184         r1 += (*ra)*c[*rj];
185         r2 += (*ra)*c2[*rj];
186         r3 += (*ra)*c3[*rj];
187         r4 += (*ra++)*c4[*rj++];
188       }
189       d[colrm + i]       = r1;
190       d[colrm + rm + i]  = r2;
191       d[colrm + rm2 + i] = r3;
192       d[colrm + rm3 + i] = r4;
193     }
194   }
195   for (; col<cn; col++) {     /* over extra columns of C */
196     for (i=0; i<am; i++) {  /* over rows of A in those columns */
197       r1 = 0.0;
198       n  = a->i[i+1] - a->i[i];
199       aj = a->j + a->i[i];
200       aa = a->a + a->i[i];
201       for (j=0; j<n; j++) {
202         r1 += (*aa++)*b1[*aj++];
203       }
204       c[i] = r1;
205     }
206     b1 += bm;
207 
208     for (i=0; i<rm; i++) {  /* over rows of R in those columns */
209       r1 = 0.0;
210       n  = r->i[i+1] - r->i[i];
211       rj = r->j + r->i[i];
212       ra = r->a + r->i[i];
213       for (j=0; j<n; j++) {
214         r1 += (*ra++)*c[*rj++];
215       }
216       d[col*rm + i] = r1;
217     }
218   }
219   ierr = PetscLogFlops(cn*2.0*(a->nz + r->nz));CHKERRQ(ierr);
220 
221   ierr = MatDenseRestoreArray(B,&b);CHKERRQ(ierr);
222   ierr = MatDenseRestoreArray(RAB,&d);CHKERRQ(ierr);
223   ierr = MatAssemblyBegin(RAB,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
224   ierr = MatAssemblyEnd(RAB,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
225   PetscFunctionReturn(0);
226 }
227 
228 PetscErrorCode MatRARtNumeric_SeqAIJ_SeqAIJ_colorrart(Mat A,Mat R,Mat C)
229 {
230   PetscErrorCode       ierr;
231   Mat_SeqAIJ           *c = (Mat_SeqAIJ*)C->data;
232   Mat_RARt             *rart=c->rart;
233   MatTransposeColoring matcoloring;
234   Mat                  Rt,RARt;
235 
236   PetscFunctionBegin;
237   /* Get dense Rt by Apply MatTransposeColoring to R */
238   matcoloring = rart->matcoloring;
239   Rt          = rart->Rt;
240   ierr  = MatTransColoringApplySpToDen(matcoloring,R,Rt);CHKERRQ(ierr);
241 
242   /* Get dense RARt = R*A*Rt -- dominates! */
243   RARt = rart->RARt;
244   ierr = MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense(R,A,Rt,RARt,rart->work);CHKERRQ(ierr);
245 
246   /* Recover C from C_dense */
247   ierr = MatTransColoringApplyDenToSp(matcoloring,RARt,C);CHKERRQ(ierr);
248   PetscFunctionReturn(0);
249 }
250 
251 PetscErrorCode MatRARtSymbolic_SeqAIJ_SeqAIJ_matmattransposemult(Mat A,Mat R,PetscReal fill,Mat *C)
252 {
253   PetscErrorCode  ierr;
254   Mat             ARt,RARt;
255   Mat_SeqAIJ     *c;
256   Mat_RARt       *rart;
257 
258   PetscFunctionBegin;
259   /* must use '-mat_no_inode' with '-matmattransmult_color 1' - do not knwo why? */
260   ierr = MatMatTransposeMultSymbolic_SeqAIJ_SeqAIJ(A,R,fill,&ARt);CHKERRQ(ierr);
261   ierr = MatMatMultSymbolic_SeqAIJ_SeqAIJ(R,ARt,fill,&RARt);CHKERRQ(ierr);
262   *C                     = RARt;
263   RARt->ops->rartnumeric = MatRARtNumeric_SeqAIJ_SeqAIJ_matmattransposemult;
264 
265   ierr = PetscNew(&rart);CHKERRQ(ierr);
266   c         = (Mat_SeqAIJ*)(*C)->data;
267   c->rart   = rart;
268   rart->ARt = ARt;
269   rart->destroy      = RARt->ops->destroy;
270   RARt->ops->destroy = MatDestroy_SeqAIJ_RARt;
271 #if defined(PETSC_USE_INFO)
272   ierr = PetscInfo(*C,"Use ARt=A*R^T, C=R*ARt via MatMatTransposeMult(). Coloring can be applied to A*R^T.\n");CHKERRQ(ierr);
273 #endif
274   PetscFunctionReturn(0);
275 }
276 
277 PetscErrorCode MatRARtNumeric_SeqAIJ_SeqAIJ_matmattransposemult(Mat A,Mat R,Mat C)
278 {
279   PetscErrorCode  ierr;
280   Mat_SeqAIJ      *c=(Mat_SeqAIJ*)C->data;
281   Mat_RARt        *rart=c->rart;
282   Mat             ARt=rart->ARt;
283 
284   PetscFunctionBegin;
285   ierr = MatMatTransposeMultNumeric_SeqAIJ_SeqAIJ(A,R,ARt);CHKERRQ(ierr); /* dominate! */
286   ierr = MatMatMultNumeric_SeqAIJ_SeqAIJ(R,ARt,C);CHKERRQ(ierr);
287   PetscFunctionReturn(0);
288 }
289 
290 PetscErrorCode MatRARtSymbolic_SeqAIJ_SeqAIJ(Mat A,Mat R,PetscReal fill,Mat *C)
291 {
292   PetscErrorCode  ierr;
293   Mat             Rt;
294   Mat_SeqAIJ      *c;
295   Mat_RARt        *rart;
296 
297   PetscFunctionBegin;
298   ierr = MatTranspose_SeqAIJ(R,MAT_INITIAL_MATRIX,&Rt);CHKERRQ(ierr);
299   ierr = MatMatMatMultSymbolic_SeqAIJ_SeqAIJ_SeqAIJ(R,A,Rt,fill,C);CHKERRQ(ierr);
300 
301   ierr = PetscNew(&rart);CHKERRQ(ierr);
302   rart->Rt = Rt;
303   c        = (Mat_SeqAIJ*)(*C)->data;
304   c->rart  = rart;
305   rart->destroy          = (*C)->ops->destroy;
306   (*C)->ops->destroy     = MatDestroy_SeqAIJ_RARt;
307   (*C)->ops->rartnumeric = MatRARtNumeric_SeqAIJ_SeqAIJ;
308 #if defined(PETSC_USE_INFO)
309   ierr = PetscInfo(*C,"Use Rt=R^T and C=R*A*Rt via MatMatMatMult() to avoid sparse inner products\n");CHKERRQ(ierr);
310 #endif
311   PetscFunctionReturn(0);
312 }
313 
314 PetscErrorCode MatRARtNumeric_SeqAIJ_SeqAIJ(Mat A,Mat R,Mat C)
315 {
316   PetscErrorCode  ierr;
317   Mat_SeqAIJ      *c = (Mat_SeqAIJ*)C->data;
318   Mat_RARt        *rart = c->rart;
319   Mat             Rt = rart->Rt;
320 
321   PetscFunctionBegin;
322   ierr = MatTranspose_SeqAIJ(R,MAT_REUSE_MATRIX,&Rt);CHKERRQ(ierr);
323   ierr = MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqAIJ(R,A,Rt,C);CHKERRQ(ierr);
324   PetscFunctionReturn(0);
325 }
326 
327 PetscErrorCode MatRARt_SeqAIJ_SeqAIJ(Mat A,Mat R,MatReuse scall,PetscReal fill,Mat *C)
328 {
329   PetscErrorCode ierr;
330   const char     *algTypes[3] = {"matmatmatmult","matmattransposemult","coloring_rart"};
331   PetscInt       alg=0; /* set default algorithm */
332 
333   PetscFunctionBegin;
334   if (scall == MAT_INITIAL_MATRIX) {
335     ierr = PetscObjectOptionsBegin((PetscObject)A);CHKERRQ(ierr);
336     PetscOptionsObject->alreadyprinted = PETSC_FALSE; /* a hack to ensure the option shows in '-help' */
337     ierr = PetscOptionsEList("-matrart_via","Algorithmic approach","MatRARt",algTypes,3,algTypes[0],&alg,NULL);CHKERRQ(ierr);
338     ierr = PetscOptionsEnd();CHKERRQ(ierr);
339 
340     ierr = PetscLogEventBegin(MAT_RARtSymbolic,A,R,0,0);CHKERRQ(ierr);
341     switch (alg) {
342     case 1:
343       /* via matmattransposemult: ARt=A*R^T, C=R*ARt - matrix coloring can be applied to A*R^T */
344       ierr = MatRARtSymbolic_SeqAIJ_SeqAIJ_matmattransposemult(A,R,fill,C);CHKERRQ(ierr);
345       break;
346     case 2:
347       /* via coloring_rart: apply coloring C = R*A*R^T                          */
348       ierr = MatRARtSymbolic_SeqAIJ_SeqAIJ_colorrart(A,R,fill,C);CHKERRQ(ierr);
349       break;
350     default:
351       /* via matmatmatmult: Rt=R^T, C=R*A*Rt - avoid inefficient sparse inner products */
352       ierr = MatRARtSymbolic_SeqAIJ_SeqAIJ(A,R,fill,C);CHKERRQ(ierr);
353       break;
354     }
355     ierr = PetscLogEventEnd(MAT_RARtSymbolic,A,R,0,0);CHKERRQ(ierr);
356   }
357 
358   ierr = PetscLogEventBegin(MAT_RARtNumeric,A,R,0,0);CHKERRQ(ierr);
359   ierr = (*(*C)->ops->rartnumeric)(A,R,*C);CHKERRQ(ierr);
360   ierr = PetscLogEventEnd(MAT_RARtNumeric,A,R,0,0);CHKERRQ(ierr);
361   PetscFunctionReturn(0);
362 }
363