xref: /petsc/src/mat/impls/aij/seq/aij.h (revision b549a33df52e18f44cd122c2139f7c5486754f82)
1 
2 #if !defined(__AIJ_H)
3 #define __AIJ_H
4 
5 #include <private/matimpl.h>
6 
7 /*
8     Struct header shared by SeqAIJ, SeqBAIJ and SeqSBAIJ matrix formats
9 */
10 #define SEQAIJHEADER(datatype)	\
11   PetscBool         roworiented;      /* if true, row-oriented input, default */\
12   PetscInt          nonew;            /* 1 don't add new nonzeros, -1 generate error on new */\
13   PetscInt          nounused;         /* -1 generate error on unused space */\
14   PetscBool         singlemalloc;     /* if true a, i, and j have been obtained with one big malloc */\
15   PetscInt          maxnz;            /* allocated nonzeros */\
16   PetscInt          *imax;            /* maximum space allocated for each row */\
17   PetscInt          *ilen;            /* actual length of each row */\
18   PetscBool         free_imax_ilen;  \
19   PetscInt          reallocs;         /* number of mallocs done during MatSetValues() \
20                                         as more values are set than were prealloced */\
21   PetscInt          rmax;             /* max nonzeros in any row */\
22   PetscBool         keepnonzeropattern;   /* keeps matrix structure same in calls to MatZeroRows()*/\
23   PetscBool         ignorezeroentries; \
24   PetscInt          *xtoy,*xtoyB;     /* map nonzero pattern of X into Y's, used by MatAXPY() */\
25   Mat               XtoY;             /* used by MatAXPY() */\
26   PetscBool         free_ij;          /* free the column indices j and row offsets i when the matrix is destroyed */ \
27   PetscBool         free_a;           /* free the numerical values when matrix is destroy */ \
28   Mat_CompressedRow compressedrow;    /* use compressed row format */                      \
29   PetscInt          nz;               /* nonzeros */                                       \
30   PetscInt          *i;               /* pointer to beginning of each row */               \
31   PetscInt          *j;               /* column values: j + i[k] - 1 is start of row k */  \
32   PetscInt          *diag;            /* pointers to diagonal elements */                  \
33   PetscBool         free_diag;         \
34   datatype          *a;               /* nonzero elements */                               \
35   PetscScalar       *solve_work;      /* work space used in MatSolve */                    \
36   IS                row, col, icol;   /* index sets, used for reorderings */ \
37   PetscBool         pivotinblocks;    /* pivot inside factorization of each diagonal block */ \
38   Mat               parent             /* set if this matrix was formed with MatDuplicate(...,MAT_SHARE_NONZERO_PATTERN,....);
39                                          means that this shares some data structures with the parent including diag, ilen, imax, i, j */
40 
41 /*
42   MATSEQAIJ format - Compressed row storage (also called Yale sparse matrix
43   format) or compressed sparse row (CSR).  The i[] and j[] arrays start at 0. For example,
44   j[i[k]+p] is the pth column in row k.  Note that the diagonal
45   matrix elements are stored with the rest of the nonzeros (not separately).
46 */
47 
48 /* Info about i-nodes (identical nodes) helper class for SeqAIJ */
49 typedef struct {
50   MatScalar   *bdiag,*ibdiag,*ssor_work;      /* diagonal blocks of matrix used for MatSOR_SeqAIJ_Inode() */
51   PetscInt    bdiagsize;                       /* length of bdiag and ibdiag */
52   PetscBool   ibdiagvalid;                     /* do ibdiag[] and bdiag[] contain the most recent values */
53 
54   PetscBool  use;
55   PetscInt   node_count;                    /* number of inodes */
56   PetscInt   *size;                         /* size of each inode */
57   PetscInt   limit;                         /* inode limit */
58   PetscInt   max_limit;                     /* maximum supported inode limit */
59   PetscBool  checked;                       /* if inodes have been checked for */
60 } Mat_SeqAIJ_Inode;
61 
62 extern PetscErrorCode MatView_SeqAIJ_Inode(Mat,PetscViewer);
63 extern PetscErrorCode MatAssemblyEnd_SeqAIJ_Inode(Mat,MatAssemblyType);
64 extern PetscErrorCode MatDestroy_SeqAIJ_Inode(Mat);
65 extern PetscErrorCode MatCreate_SeqAIJ_Inode(Mat);
66 extern PetscErrorCode MatSetOption_SeqAIJ_Inode(Mat,MatOption,PetscBool );
67 extern PetscErrorCode MatDuplicate_SeqAIJ_Inode(Mat,MatDuplicateOption,Mat*);
68 extern PetscErrorCode MatDuplicateNoCreate_SeqAIJ(Mat,Mat,MatDuplicateOption,PetscBool );
69 extern PetscErrorCode MatLUFactorNumeric_SeqAIJ_Inode_inplace(Mat,Mat,const MatFactorInfo*);
70 extern PetscErrorCode MatLUFactorNumeric_SeqAIJ_Inode(Mat,Mat,const MatFactorInfo*);
71 
72 typedef struct {
73   SEQAIJHEADER(MatScalar);
74   Mat_SeqAIJ_Inode inode;
75   MatScalar        *saved_values;             /* location for stashing nonzero values of matrix */
76 
77   PetscScalar      *idiag,*mdiag,*ssor_work;  /* inverse of diagonal entries, diagonal values and workspace for Eisenstat trick */
78   PetscBool        idiagvalid;                     /* current idiag[] and mdiag[] are valid */
79   PetscScalar      *ibdiag;                   /* inverses of block diagonals */
80   PetscBool        ibdiagvalid;               /* inverses of block diagonals are valid. */
81   PetscScalar      fshift,omega;                   /* last used omega and fshift */
82 
83   ISColoring       coloring;                  /* set with MatADSetColoring() used by MatADSetValues() */
84 } Mat_SeqAIJ;
85 
86 typedef struct {
87   MatTransposeColoring      matcoloring;
88   Mat                       Bt_den;  /* dense matrix of B^T */
89   Mat                       ABt_den; /* dense matrix of A*B^T */
90   PetscBool                 usecoloring;
91   PetscErrorCode (*destroy)(Mat);
92 } Mat_MatMatMultTrans;
93 
94 typedef struct {
95   MatTransposeColoring matcoloring;
96   Mat                  Rt;   /* dense matrix of R^T */
97   Mat                  ARt;  /* dense matrix of A*R^T */
98   Mat                  RARt; /* dense matrix of R*A*R^T */
99   PetscErrorCode (*destroy)(Mat);
100 } Mat_RARt;
101 
102 /*
103   Frees the a, i, and j arrays from the XAIJ (AIJ, BAIJ, and SBAIJ) matrix types
104 */
105 #undef __FUNCT__
106 #define __FUNCT__ "MatSeqXAIJFreeAIJ"
107 PETSC_STATIC_INLINE PetscErrorCode MatSeqXAIJFreeAIJ(Mat AA,MatScalar **a,PetscInt **j,PetscInt **i)
108 {
109   PetscErrorCode ierr;
110   Mat_SeqAIJ     *A = (Mat_SeqAIJ*) AA->data;
111   if (A->singlemalloc) {
112     ierr = PetscFree3(*a,*j,*i);CHKERRQ(ierr);
113   } else {
114     if (A->free_a)  {ierr = PetscFree(*a);CHKERRQ(ierr);}
115     if (A->free_ij) {ierr = PetscFree(*j);CHKERRQ(ierr);}
116     if (A->free_ij) {ierr = PetscFree(*i);CHKERRQ(ierr);}
117   }
118   return 0;
119 }
120 /*
121     Allocates larger a, i, and j arrays for the XAIJ (AIJ, BAIJ, and SBAIJ) matrix types
122     This is a macro because it takes the datatype as an argument which can be either a Mat or a MatScalar
123 */
124 #define MatSeqXAIJReallocateAIJ(Amat,AM,BS2,NROW,ROW,COL,RMAX,AA,AI,AJ,RP,AP,AIMAX,NONEW,datatype) \
125   if (NROW >= RMAX) {\
126 	Mat_SeqAIJ *Ain = (Mat_SeqAIJ*)Amat->data;\
127         /* there is no extra room in row, therefore enlarge */ \
128         PetscInt   CHUNKSIZE = 15,new_nz = AI[AM] + CHUNKSIZE,len,*new_i=0,*new_j=0; \
129         datatype   *new_a; \
130  \
131         if (NONEW == -2) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"New nonzero at (%D,%D) caused a malloc",ROW,COL); \
132         /* malloc new storage space */ \
133         ierr = PetscMalloc3(BS2*new_nz,datatype,&new_a,new_nz,PetscInt,&new_j,AM+1,PetscInt,&new_i);CHKERRQ(ierr);\
134  \
135         /* copy over old data into new slots */ \
136         for (ii=0; ii<ROW+1; ii++) {new_i[ii] = AI[ii];} \
137         for (ii=ROW+1; ii<AM+1; ii++) {new_i[ii] = AI[ii]+CHUNKSIZE;} \
138         ierr = PetscMemcpy(new_j,AJ,(AI[ROW]+NROW)*sizeof(PetscInt));CHKERRQ(ierr); \
139         len = (new_nz - CHUNKSIZE - AI[ROW] - NROW); \
140         ierr = PetscMemcpy(new_j+AI[ROW]+NROW+CHUNKSIZE,AJ+AI[ROW]+NROW,len*sizeof(PetscInt));CHKERRQ(ierr); \
141         ierr = PetscMemcpy(new_a,AA,BS2*(AI[ROW]+NROW)*sizeof(datatype));CHKERRQ(ierr); \
142         ierr = PetscMemzero(new_a+BS2*(AI[ROW]+NROW),BS2*CHUNKSIZE*sizeof(datatype));CHKERRQ(ierr);\
143         ierr = PetscMemcpy(new_a+BS2*(AI[ROW]+NROW+CHUNKSIZE),AA+BS2*(AI[ROW]+NROW),BS2*len*sizeof(datatype));CHKERRQ(ierr);  \
144         /* free up old matrix storage */ \
145         ierr = MatSeqXAIJFreeAIJ(A,&Ain->a,&Ain->j,&Ain->i);CHKERRQ(ierr);\
146         AA = new_a; \
147         Ain->a = (MatScalar*) new_a;		   \
148         AI = Ain->i = new_i; AJ = Ain->j = new_j;  \
149         Ain->singlemalloc = PETSC_TRUE; \
150  \
151         RP          = AJ + AI[ROW]; AP = AA + BS2*AI[ROW]; \
152         RMAX        = AIMAX[ROW] = AIMAX[ROW] + CHUNKSIZE; \
153         Ain->maxnz += BS2*CHUNKSIZE; \
154         Ain->reallocs++; \
155       } \
156 
157 
158 EXTERN_C_BEGIN
159 extern PetscErrorCode MatSeqAIJSetPreallocation_SeqAIJ(Mat,PetscInt,const PetscInt*);
160 EXTERN_C_END
161 extern PetscErrorCode MatILUFactorSymbolic_SeqAIJ_inplace(Mat,Mat,IS,IS,const MatFactorInfo*);
162 extern PetscErrorCode MatILUFactorSymbolic_SeqAIJ(Mat,Mat,IS,IS,const MatFactorInfo*);
163 extern PetscErrorCode MatILUFactorSymbolic_SeqAIJ_ilu0(Mat,Mat,IS,IS,const MatFactorInfo*);
164 
165 extern PetscErrorCode MatICCFactorSymbolic_SeqAIJ_inplace(Mat,Mat,IS,const MatFactorInfo*);
166 extern PetscErrorCode MatICCFactorSymbolic_SeqAIJ(Mat,Mat,IS,const MatFactorInfo*);
167 extern PetscErrorCode MatCholeskyFactorSymbolic_SeqAIJ_inplace(Mat,Mat,IS,const MatFactorInfo*);
168 extern PetscErrorCode MatCholeskyFactorSymbolic_SeqAIJ(Mat,Mat,IS,const MatFactorInfo*);
169 extern PetscErrorCode MatCholeskyFactorNumeric_SeqAIJ_inplace(Mat,Mat,const MatFactorInfo*);
170 extern PetscErrorCode MatCholeskyFactorNumeric_SeqAIJ(Mat,Mat,const MatFactorInfo*);
171 extern PetscErrorCode MatDuplicate_SeqAIJ(Mat,MatDuplicateOption,Mat*);
172 extern PetscErrorCode MatCopy_SeqAIJ(Mat,Mat,MatStructure);
173 extern PetscErrorCode MatMissingDiagonal_SeqAIJ(Mat,PetscBool *,PetscInt*);
174 extern PetscErrorCode MatMarkDiagonal_SeqAIJ(Mat);
175 
176 extern PetscErrorCode MatMult_SeqAIJ(Mat A,Vec,Vec);
177 extern PetscErrorCode MatMultAdd_SeqAIJ(Mat A,Vec,Vec,Vec);
178 extern PetscErrorCode MatMultTranspose_SeqAIJ(Mat A,Vec,Vec);
179 extern PetscErrorCode MatMultTransposeAdd_SeqAIJ(Mat A,Vec,Vec,Vec);
180 extern PetscErrorCode MatSOR_SeqAIJ(Mat,Vec,PetscReal,MatSORType,PetscReal,PetscInt,PetscInt,Vec);
181 
182 extern PetscErrorCode MatSetColoring_SeqAIJ(Mat,ISColoring);
183 extern PetscErrorCode MatSetValuesAdic_SeqAIJ(Mat,void*);
184 extern PetscErrorCode MatSetValuesAdifor_SeqAIJ(Mat,PetscInt,void*);
185 
186 extern PetscErrorCode MatGetSymbolicTranspose_SeqAIJ(Mat,PetscInt *[],PetscInt *[]);
187 extern PetscErrorCode MatGetSymbolicTransposeReduced_SeqAIJ(Mat,PetscInt,PetscInt,PetscInt *[],PetscInt *[]);
188 extern PetscErrorCode MatRestoreSymbolicTranspose_SeqAIJ(Mat,PetscInt *[],PetscInt *[]);
189 extern PetscErrorCode MatToSymmetricIJ_SeqAIJ(PetscInt,PetscInt*,PetscInt*,PetscInt,PetscInt,PetscInt**,PetscInt**);
190 extern PetscErrorCode MatLUFactorSymbolic_SeqAIJ_inplace(Mat,Mat,IS,IS,const MatFactorInfo*);
191 extern PetscErrorCode MatLUFactorSymbolic_SeqAIJ(Mat,Mat,IS,IS,const MatFactorInfo*);
192 extern PetscErrorCode MatLUFactorNumeric_SeqAIJ_inplace(Mat,Mat,const MatFactorInfo*);
193 extern PetscErrorCode MatLUFactorNumeric_SeqAIJ(Mat,Mat,const MatFactorInfo*);
194 extern PetscErrorCode MatLUFactorNumeric_SeqAIJ_InplaceWithPerm(Mat,Mat,const MatFactorInfo*);
195 extern PetscErrorCode MatLUFactor_SeqAIJ(Mat,IS,IS,const MatFactorInfo*);
196 extern PetscErrorCode MatSolve_SeqAIJ_inplace(Mat,Vec,Vec);
197 extern PetscErrorCode MatSolve_SeqAIJ(Mat,Vec,Vec);
198 extern PetscErrorCode MatSolve_SeqAIJ_Inode_inplace(Mat,Vec,Vec);
199 extern PetscErrorCode MatSolve_SeqAIJ_Inode(Mat,Vec,Vec);
200 extern PetscErrorCode MatSolve_SeqAIJ_NaturalOrdering_inplace(Mat,Vec,Vec);
201 extern PetscErrorCode MatSolve_SeqAIJ_NaturalOrdering(Mat,Vec,Vec);
202 extern PetscErrorCode MatSolve_SeqAIJ_InplaceWithPerm(Mat,Vec,Vec);
203 extern PetscErrorCode MatSolveAdd_SeqAIJ_inplace(Mat,Vec,Vec,Vec);
204 extern PetscErrorCode MatSolveAdd_SeqAIJ(Mat,Vec,Vec,Vec);
205 extern PetscErrorCode MatSolveTranspose_SeqAIJ_inplace(Mat,Vec,Vec);
206 extern PetscErrorCode MatSolveTranspose_SeqAIJ(Mat,Vec,Vec);
207 extern PetscErrorCode MatSolveTransposeAdd_SeqAIJ_inplace(Mat,Vec,Vec,Vec);
208 extern PetscErrorCode MatSolveTransposeAdd_SeqAIJ(Mat,Vec,Vec,Vec);
209 extern PetscErrorCode MatMatSolve_SeqAIJ_inplace(Mat,Mat,Mat);
210 extern PetscErrorCode MatMatSolve_SeqAIJ(Mat,Mat,Mat);
211 extern PetscErrorCode MatEqual_SeqAIJ(Mat A,Mat B,PetscBool * flg);
212 extern PetscErrorCode MatFDColoringCreate_SeqAIJ(Mat,ISColoring,MatFDColoring);
213 extern PetscErrorCode MatLoad_SeqAIJ(Mat,PetscViewer);
214 extern PetscErrorCode RegisterApplyPtAPRoutines_Private(Mat);
215 extern PetscErrorCode MatMatMultSymbolic_SeqAIJ_SeqAIJ(Mat,Mat,PetscReal,Mat*);
216 extern PetscErrorCode MatMatMultNumeric_SeqAIJ_SeqAIJ(Mat,Mat,Mat);
217 
218 extern PetscErrorCode MatPtAPSymbolic_SeqAIJ(Mat,Mat,PetscReal,Mat*);
219 extern PetscErrorCode MatPtAPNumeric_SeqAIJ(Mat,Mat,Mat);
220 extern PetscErrorCode MatPtAPSymbolic_SeqAIJ_SeqAIJ(Mat,Mat,PetscReal,Mat*);
221 extern PetscErrorCode MatPtAPNumeric_SeqAIJ_SeqAIJ(Mat,Mat,Mat);
222 extern PetscErrorCode MatRARtSymbolic_SeqAIJ_SeqAIJ(Mat,Mat,PetscReal,Mat*);
223 extern PetscErrorCode MatRARtNumeric_SeqAIJ_SeqAIJ(Mat,Mat,Mat);
224 
225 extern PetscErrorCode MatTransposeMatMult_SeqAIJ_SeqAIJ(Mat,Mat,MatReuse,PetscReal,Mat*);
226 extern PetscErrorCode MatTransposeMatMultSymbolic_SeqAIJ_SeqAIJ(Mat,Mat,PetscReal,Mat*);
227 extern PetscErrorCode MatTransposeMatMultNumeric_SeqAIJ_SeqAIJ(Mat,Mat,Mat);
228 extern PetscErrorCode MatMatTransposeMult_SeqAIJ_SeqAIJ(Mat,Mat,MatReuse,PetscReal,Mat*);
229 extern PetscErrorCode MatMatTransposeMultSymbolic_SeqAIJ_SeqAIJ(Mat,Mat,PetscReal,Mat*);
230 extern PetscErrorCode MatMatTransposeMultNumeric_SeqAIJ_SeqAIJ(Mat,Mat,Mat);
231 extern PetscErrorCode MatTransposeColoringCreate_SeqAIJ(Mat,ISColoring,MatTransposeColoring);
232 extern PetscErrorCode MatTransColoringApplySpToDen_SeqAIJ(MatTransposeColoring,Mat,Mat);
233 extern PetscErrorCode MatTransColoringApplyDenToSp_SeqAIJ(MatTransposeColoring,Mat,Mat);
234 
235 extern PetscErrorCode MatSetValues_SeqAIJ(Mat,PetscInt,const PetscInt[],PetscInt,const PetscInt[],const PetscScalar[],InsertMode);
236 extern PetscErrorCode MatGetRow_SeqAIJ(Mat,PetscInt,PetscInt*,PetscInt**,PetscScalar**);
237 extern PetscErrorCode MatRestoreRow_SeqAIJ(Mat,PetscInt,PetscInt*,PetscInt**,PetscScalar**);
238 extern PetscErrorCode MatAXPY_SeqAIJ(Mat,PetscScalar,Mat,MatStructure);
239 extern PetscErrorCode MatGetRowIJ_SeqAIJ(Mat,PetscInt,PetscBool ,PetscBool ,PetscInt*,PetscInt *[],PetscInt *[],PetscBool  *);
240 extern PetscErrorCode MatRestoreRowIJ_SeqAIJ(Mat,PetscInt,PetscBool ,PetscBool ,PetscInt *,PetscInt *[],PetscInt *[],PetscBool  *);
241 extern PetscErrorCode MatGetColumnIJ_SeqAIJ(Mat,PetscInt,PetscBool ,PetscBool ,PetscInt*,PetscInt *[],PetscInt *[],PetscBool  *);
242 extern PetscErrorCode MatRestoreColumnIJ_SeqAIJ(Mat,PetscInt,PetscBool ,PetscBool ,PetscInt *,PetscInt *[],PetscInt *[],PetscBool  *);
243 extern PetscErrorCode MatDestroy_SeqAIJ(Mat);
244 extern PetscErrorCode MatView_SeqAIJ(Mat,PetscViewer);
245 
246 extern PetscErrorCode Mat_CheckInode(Mat,PetscBool );
247 extern PetscErrorCode Mat_CheckInode_FactorLU(Mat,PetscBool );
248 
249 extern PetscErrorCode MatAXPYGetPreallocation_SeqAIJ(Mat,Mat,PetscInt*);
250 
251 EXTERN_C_BEGIN
252 extern PetscErrorCode  MatConvert_SeqAIJ_SeqSBAIJ(Mat,const MatType,MatReuse,Mat*);
253 extern PetscErrorCode  MatConvert_SeqAIJ_SeqBAIJ(Mat,const MatType,MatReuse,Mat*);
254 extern PetscErrorCode  MatConvert_SeqAIJ_SeqAIJPERM(Mat,const MatType,MatReuse,Mat*);
255 extern PetscErrorCode  MatReorderForNonzeroDiagonal_SeqAIJ(Mat,PetscReal,IS,IS);
256 extern PetscErrorCode  MatMatMult_SeqAIJ_SeqAIJ(Mat,Mat,MatReuse,PetscReal,Mat*);
257 extern PetscErrorCode  MatRARt_SeqAIJ_SeqAIJ(Mat,Mat,MatReuse,PetscReal,Mat*);
258 extern PetscErrorCode  MatCreate_SeqAIJ(Mat);
259 EXTERN_C_END
260 extern PetscErrorCode  MatAssemblyEnd_SeqAIJ(Mat,MatAssemblyType);
261 extern PetscErrorCode  MatDestroy_SeqAIJ(Mat);
262 
263 
264 /*
265     PetscSparseDenseMinusDot - The inner kernel of triangular solves and Gauss-Siedel smoothing. \sum_i xv[i] * r[xi[i]] for CSR storage
266 
267   Input Parameters:
268 +  nnz - the number of entries
269 .  r - the array of vector values
270 .  xv - the matrix values for the row
271 -  xi - the column indices of the nonzeros in the row
272 
273   Output Parameter:
274 .  sum - negative the sum of results
275 
276   PETSc compile flags:
277 +   PETSC_KERNEL_USE_UNROLL_4 -   don't use this; it changes nnz and hence is WRONG
278 -   PETSC_KERNEL_USE_UNROLL_2 -
279 
280 .seealso: PetscSparseDensePlusDot()
281 
282 */
283 #ifdef PETSC_KERNEL_USE_UNROLL_4
284 #define PetscSparseDenseMinusDot(sum,r,xv,xi,nnz) {\
285 if (nnz > 0) {\
286 switch (nnz & 0x3) {\
287 case 3: sum -= *xv++ * r[*xi++];\
288 case 2: sum -= *xv++ * r[*xi++];\
289 case 1: sum -= *xv++ * r[*xi++];\
290 nnz -= 4;}\
291 while (nnz > 0) {\
292 sum -=  xv[0] * r[xi[0]] - xv[1] * r[xi[1]] -\
293 	xv[2] * r[xi[2]] - xv[3] * r[xi[3]];\
294 xv  += 4; xi += 4; nnz -= 4; }}}
295 
296 #elif defined(PETSC_KERNEL_USE_UNROLL_2)
297 #define PetscSparseDenseMinusDot(sum,r,xv,xi,nnz) {\
298 PetscInt __i,__i1,__i2;\
299 for(__i=0;__i<nnz-1;__i+=2) {__i1 = xi[__i]; __i2=xi[__i+1];\
300 sum -= (xv[__i]*r[__i1] + xv[__i+1]*r[__i2]);}\
301 if (nnz & 0x1) sum -= xv[__i] * r[xi[__i]];}
302 
303 #else
304 #define PetscSparseDenseMinusDot(sum,r,xv,xi,nnz) {\
305 PetscInt __i;\
306 for(__i=0;__i<nnz;__i++) sum -= xv[__i] * r[xi[__i]];}
307 #endif
308 
309 
310 
311 /*
312     PetscSparseDensePlusDot - The inner kernel of matrix-vector product \sum_i xv[i] * r[xi[i]] for CSR storage
313 
314   Input Parameters:
315 +  nnz - the number of entries
316 .  r - the array of vector values
317 .  xv - the matrix values for the row
318 -  xi - the column indices of the nonzeros in the row
319 
320   Output Parameter:
321 .  sum - the sum of results
322 
323   PETSc compile flags:
324 +   PETSC_KERNEL_USE_UNROLL_4 -  don't use this; it changes nnz and hence is WRONG
325 -   PETSC_KERNEL_USE_UNROLL_2 -
326 
327 .seealso: PetscSparseDenseMinusDot()
328 
329 */
330 #ifdef PETSC_KERNEL_USE_UNROLL_4
331 #define PetscSparseDensePlusDot(sum,r,xv,xi,nnz) {\
332 if (nnz > 0) {\
333 switch (nnz & 0x3) {\
334 case 3: sum += *xv++ * r[*xi++];\
335 case 2: sum += *xv++ * r[*xi++];\
336 case 1: sum += *xv++ * r[*xi++];\
337 nnz -= 4;}\
338 while (nnz > 0) {\
339 sum +=  xv[0] * r[xi[0]] + xv[1] * r[xi[1]] +\
340 	xv[2] * r[xi[2]] + xv[3] * r[xi[3]];\
341 xv  += 4; xi += 4; nnz -= 4; }}}
342 
343 #elif defined(PETSC_KERNEL_USE_UNROLL_2)
344 #define PetscSparseDensePlusDot(sum,r,xv,xi,nnz) {\
345 PetscInt __i,__i1,__i2;\
346 for(__i=0;__i<nnz-1;__i+=2) {__i1 = xi[__i]; __i2=xi[__i+1];\
347 sum += (xv[__i]*r[__i1] + xv[__i+1]*r[__i2]);}\
348 if (nnz & 0x1) sum += xv[__i] * r[xi[__i]];}
349 
350 #else
351 #define PetscSparseDensePlusDot(sum,r,xv,xi,nnz) {\
352  PetscInt __i;\
353 for(__i=0;__i<nnz;__i++) sum += xv[__i] * r[xi[__i]];}
354 #endif
355 
356 #endif
357