Actual source code: crl.c
petsc-3.14.6 2021-03-30
2: /*
3: Defines a matrix-vector product for the MATSEQAIJCRL matrix class.
4: This class is derived from the MATSEQAIJ class and retains the
5: compressed row storage (aka Yale sparse matrix format) but augments
6: it with a column oriented storage that is more efficient for
7: matrix vector products on Vector machines.
9: CRL stands for constant row length (that is the same number of columns
10: is kept (padded with zeros) for each row of the sparse matrix.
11: */
12: #include <../src/mat/impls/aij/seq/crl/crl.h>
14: PetscErrorCode MatDestroy_SeqAIJCRL(Mat A)
15: {
17: Mat_AIJCRL *aijcrl = (Mat_AIJCRL*) A->spptr;
19: /* Free everything in the Mat_AIJCRL data structure. */
20: if (aijcrl) {
21: PetscFree2(aijcrl->acols,aijcrl->icols);
22: }
23: PetscFree(A->spptr);
24: PetscObjectChangeTypeName((PetscObject)A, MATSEQAIJ);
25: MatDestroy_SeqAIJ(A);
26: return(0);
27: }
29: PetscErrorCode MatDuplicate_AIJCRL(Mat A, MatDuplicateOption op, Mat *M)
30: {
32: SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Cannot duplicate AIJCRL matrices yet");
33: }
35: PetscErrorCode MatSeqAIJCRL_create_aijcrl(Mat A)
36: {
37: Mat_SeqAIJ *a = (Mat_SeqAIJ*)(A)->data;
38: Mat_AIJCRL *aijcrl = (Mat_AIJCRL*) A->spptr;
39: PetscInt m = A->rmap->n; /* Number of rows in the matrix. */
40: PetscInt *aj = a->j; /* From the CSR representation; points to the beginning of each row. */
41: PetscInt i, j,rmax = a->rmax,*icols, *ilen = a->ilen;
42: MatScalar *aa = a->a;
43: PetscScalar *acols;
47: aijcrl->nz = a->nz;
48: aijcrl->m = A->rmap->n;
49: aijcrl->rmax = rmax;
51: PetscFree2(aijcrl->acols,aijcrl->icols);
52: PetscMalloc2(rmax*m,&aijcrl->acols,rmax*m,&aijcrl->icols);
53: acols = aijcrl->acols;
54: icols = aijcrl->icols;
55: for (i=0; i<m; i++) {
56: for (j=0; j<ilen[i]; j++) {
57: acols[j*m+i] = *aa++;
58: icols[j*m+i] = *aj++;
59: }
60: for (; j<rmax; j++) { /* empty column entries */
61: acols[j*m+i] = 0.0;
62: icols[j*m+i] = (j) ? icols[(j-1)*m+i] : 0; /* handle case where row is EMPTY */
63: }
64: }
65: PetscInfo2(A,"Percentage of 0's introduced for vectorized multiply %g. Rmax= %D\n",1.0-((double)a->nz)/((double)(rmax*m)),rmax);
66: return(0);
67: }
69: PetscErrorCode MatAssemblyEnd_SeqAIJCRL(Mat A, MatAssemblyType mode)
70: {
72: Mat_SeqAIJ *a = (Mat_SeqAIJ*)A->data;
75: a->inode.use = PETSC_FALSE;
77: MatAssemblyEnd_SeqAIJ(A,mode);
78: if (mode == MAT_FLUSH_ASSEMBLY) return(0);
80: /* Now calculate the permutation and grouping information. */
81: MatSeqAIJCRL_create_aijcrl(A);
82: return(0);
83: }
85: #include <../src/mat/impls/aij/seq/crl/ftn-kernels/fmultcrl.h>
87: /*
88: Shared by both sequential and parallel versions of CRL matrix: MATMPIAIJCRL and MATSEQAIJCRL
89: - the scatter is used only in the parallel version
91: */
92: PetscErrorCode MatMult_AIJCRL(Mat A,Vec xx,Vec yy)
93: {
94: Mat_AIJCRL *aijcrl = (Mat_AIJCRL*) A->spptr;
95: PetscInt m = aijcrl->m; /* Number of rows in the matrix. */
96: PetscInt rmax = aijcrl->rmax,*icols = aijcrl->icols;
97: PetscScalar *acols = aijcrl->acols;
98: PetscErrorCode ierr;
99: PetscScalar *y;
100: const PetscScalar *x;
101: #if !defined(PETSC_USE_FORTRAN_KERNEL_MULTCRL)
102: PetscInt i,j,ii;
103: #endif
105: #if defined(PETSC_HAVE_PRAGMA_DISJOINT)
106: #pragma disjoint(*x,*y,*aa)
107: #endif
110: if (aijcrl->xscat) {
111: VecCopy(xx,aijcrl->xwork);
112: /* get remote values needed for local part of multiply */
113: VecScatterBegin(aijcrl->xscat,xx,aijcrl->fwork,INSERT_VALUES,SCATTER_FORWARD);
114: VecScatterEnd(aijcrl->xscat,xx,aijcrl->fwork,INSERT_VALUES,SCATTER_FORWARD);
115: xx = aijcrl->xwork;
116: }
118: VecGetArrayRead(xx,&x);
119: VecGetArray(yy,&y);
121: #if defined(PETSC_USE_FORTRAN_KERNEL_MULTCRL)
122: fortranmultcrl_(&m,&rmax,x,y,icols,acols);
123: #else
125: /* first column */
126: for (j=0; j<m; j++) y[j] = acols[j]*x[icols[j]];
128: /* other columns */
129: #if defined(PETSC_HAVE_CRAY_VECTOR)
130: #pragma _CRI preferstream
131: #endif
132: for (i=1; i<rmax; i++) {
133: ii = i*m;
134: #if defined(PETSC_HAVE_CRAY_VECTOR)
135: #pragma _CRI prefervector
136: #endif
137: for (j=0; j<m; j++) y[j] = y[j] + acols[ii+j]*x[icols[ii+j]];
138: }
139: #if defined(PETSC_HAVE_CRAY_VECTOR)
140: #pragma _CRI ivdep
141: #endif
143: #endif
144: PetscLogFlops(2.0*aijcrl->nz - m);
145: VecRestoreArrayRead(xx,&x);
146: VecRestoreArray(yy,&y);
147: return(0);
148: }
151: /* MatConvert_SeqAIJ_SeqAIJCRL converts a SeqAIJ matrix into a
152: * SeqAIJCRL matrix. This routine is called by the MatCreate_SeqAIJCRL()
153: * routine, but can also be used to convert an assembled SeqAIJ matrix
154: * into a SeqAIJCRL one. */
155: PETSC_INTERN PetscErrorCode MatConvert_SeqAIJ_SeqAIJCRL(Mat A,MatType type,MatReuse reuse,Mat *newmat)
156: {
158: Mat B = *newmat;
159: Mat_AIJCRL *aijcrl;
160: PetscBool sametype;
163: if (reuse == MAT_INITIAL_MATRIX) {
164: MatDuplicate(A,MAT_COPY_VALUES,&B);
165: }
166: PetscObjectTypeCompare((PetscObject)A,type,&sametype);
167: if (sametype) return(0);
169: PetscNewLog(B,&aijcrl);
170: B->spptr = (void*) aijcrl;
172: /* Set function pointers for methods that we inherit from AIJ but override. */
173: B->ops->duplicate = MatDuplicate_AIJCRL;
174: B->ops->assemblyend = MatAssemblyEnd_SeqAIJCRL;
175: B->ops->destroy = MatDestroy_SeqAIJCRL;
176: B->ops->mult = MatMult_AIJCRL;
178: /* If A has already been assembled, compute the permutation. */
179: if (A->assembled) {
180: MatSeqAIJCRL_create_aijcrl(B);
181: }
182: PetscObjectChangeTypeName((PetscObject)B,MATSEQAIJCRL);
183: *newmat = B;
184: return(0);
185: }
187: /*@C
188: MatCreateSeqAIJCRL - Creates a sparse matrix of type SEQAIJCRL.
189: This type inherits from AIJ, but stores some additional
190: information that is used to allow better vectorization of
191: the matrix-vector product. At the cost of increased storage, the AIJ formatted
192: matrix can be copied to a format in which pieces of the matrix are
193: stored in ELLPACK format, allowing the vectorized matrix multiply
194: routine to use stride-1 memory accesses. As with the AIJ type, it is
195: important to preallocate matrix storage in order to get good assembly
196: performance.
198: Collective
200: Input Parameters:
201: + comm - MPI communicator, set to PETSC_COMM_SELF
202: . m - number of rows
203: . n - number of columns
204: . nz - number of nonzeros per row (same for all rows)
205: - nnz - array containing the number of nonzeros in the various rows
206: (possibly different for each row) or NULL
208: Output Parameter:
209: . A - the matrix
211: Notes:
212: If nnz is given then nz is ignored
214: Level: intermediate
216: .seealso: MatCreate(), MatCreateMPIAIJPERM(), MatSetValues()
217: @*/
218: PetscErrorCode MatCreateSeqAIJCRL(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt nz,const PetscInt nnz[],Mat *A)
219: {
223: MatCreate(comm,A);
224: MatSetSizes(*A,m,n,m,n);
225: MatSetType(*A,MATSEQAIJCRL);
226: MatSeqAIJSetPreallocation_SeqAIJ(*A,nz,nnz);
227: return(0);
228: }
230: PETSC_EXTERN PetscErrorCode MatCreate_SeqAIJCRL(Mat A)
231: {
235: MatSetType(A,MATSEQAIJ);
236: MatConvert_SeqAIJ_SeqAIJCRL(A,MATSEQAIJCRL,MAT_INPLACE_MATRIX,&A);
237: return(0);
238: }