xref: /petsc/src/mat/impls/aij/seq/aij.h (revision fbdbba38e26b2ef0d990075fdf84158aaf92324c)
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   PetscTruth        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   PetscTruth        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   PetscTruth        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   PetscTruth        keepnonzeropattern;   /* keeps matrix structure same in calls to MatZeroRows()*/\
23   PetscTruth        ignorezeroentries; \
24   PetscInt          *xtoy,*xtoyB;     /* map nonzero pattern of X into Y's, used by MatAXPY() */\
25   Mat               XtoY;             /* used by MatAXPY() */\
26   PetscTruth        free_ij;          /* free the column indices j and row offsets i when the matrix is destroyed */ \
27   PetscTruth        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   PetscTruth        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   PetscTruth        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   PetscTruth  ibdiagvalid;                     /* do ibdiag[] and bdiag[] contain the most recent values */
53 
54   PetscTruth 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   PetscTruth 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,PetscTruth);
67 EXTERN PetscErrorCode MatDuplicate_SeqAIJ_Inode(Mat,MatDuplicateOption,Mat*);
68 EXTERN PetscErrorCode MatLUFactorNumeric_SeqAIJ_Inode_inplace(Mat,Mat,const MatFactorInfo*);
69 EXTERN PetscErrorCode MatLUFactorNumeric_SeqAIJ_Inode(Mat,Mat,const MatFactorInfo*);
70 
71 typedef struct {
72   SEQAIJHEADER(MatScalar);
73   Mat_SeqAIJ_Inode inode;
74   MatScalar        *saved_values;             /* location for stashing nonzero values of matrix */
75 
76   PetscScalar      *idiag,*mdiag,*ssor_work;  /* inverse of diagonal entries, diagonal values and workspace for Eisenstat trick */
77   PetscTruth       idiagvalid;                     /* current idiag[] and mdiag[] are valid */
78   PetscScalar      fshift,omega;                   /* last used omega and fshift */
79 
80   ISColoring       coloring;                  /* set with MatADSetColoring() used by MatADSetValues() */
81   //#if defined(PETSC_HAVE_CUDA)
82   //cusp::csr_matrix<PetscInt,PetscScalar,cusp::device_memory>* GPUmatrix; /* pointer to the csr matrix on the GPU */
83   //PetscCudaFlag    valid_GPU_matrix; /* this flag type is defined in vecimpl.h */
84   //#endif
85 
86 } Mat_SeqAIJ;
87 
88 /*
89     Frees the a, i, and j arrays from the XAIJ (AIJ, BAIJ, and SBAIJ) matrix types
90 */
91 #undef __FUNCT__
92 #define __FUNCT__ "MatSeqXAIJFreeAIJ"
93 PETSC_STATIC_INLINE PetscErrorCode MatSeqXAIJFreeAIJ(Mat AA,MatScalar **a,PetscInt **j,PetscInt **i)
94 {
95                                      PetscErrorCode ierr;
96                                      Mat_SeqAIJ     *A = (Mat_SeqAIJ*) AA->data;
97                                      if (A->singlemalloc) {
98                                        ierr = PetscFree3(*a,*j,*i);CHKERRQ(ierr);
99                                      } else {
100                                        if (A->free_a  && *a) {ierr = PetscFree(*a);CHKERRQ(ierr);}
101                                        if (A->free_ij && *j) {ierr = PetscFree(*j);CHKERRQ(ierr);}
102                                        if (A->free_ij && *i) {ierr = PetscFree(*i);CHKERRQ(ierr);}
103                                      }
104                                      *a = 0; *j = 0; *i = 0;
105                                      return 0;
106                                    }
107 /*
108     Allocates larger a, i, and j arrays for the XAIJ (AIJ, BAIJ, and SBAIJ) matrix types
109     This is a macro because it takes the datatype as an argument which can be either a Mat or a MatScalar
110 */
111 #define MatSeqXAIJReallocateAIJ(Amat,AM,BS2,NROW,ROW,COL,RMAX,AA,AI,AJ,RP,AP,AIMAX,NONEW,datatype) \
112   if (NROW >= RMAX) {\
113 	Mat_SeqAIJ *Ain = (Mat_SeqAIJ*)Amat->data;\
114         /* there is no extra room in row, therefore enlarge */ \
115         PetscInt   CHUNKSIZE = 15,new_nz = AI[AM] + CHUNKSIZE,len,*new_i=0,*new_j=0; \
116         datatype   *new_a; \
117  \
118         if (NONEW == -2) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"New nonzero at (%D,%D) caused a malloc",ROW,COL); \
119         /* malloc new storage space */ \
120         ierr = PetscMalloc3(BS2*new_nz,datatype,&new_a,new_nz,PetscInt,&new_j,AM+1,PetscInt,&new_i);CHKERRQ(ierr);\
121  \
122         /* copy over old data into new slots */ \
123         for (ii=0; ii<ROW+1; ii++) {new_i[ii] = AI[ii];} \
124         for (ii=ROW+1; ii<AM+1; ii++) {new_i[ii] = AI[ii]+CHUNKSIZE;} \
125         ierr = PetscMemcpy(new_j,AJ,(AI[ROW]+NROW)*sizeof(PetscInt));CHKERRQ(ierr); \
126         len = (new_nz - CHUNKSIZE - AI[ROW] - NROW); \
127         ierr = PetscMemcpy(new_j+AI[ROW]+NROW+CHUNKSIZE,AJ+AI[ROW]+NROW,len*sizeof(PetscInt));CHKERRQ(ierr); \
128         ierr = PetscMemcpy(new_a,AA,BS2*(AI[ROW]+NROW)*sizeof(datatype));CHKERRQ(ierr); \
129         ierr = PetscMemzero(new_a+BS2*(AI[ROW]+NROW),BS2*CHUNKSIZE*sizeof(datatype));CHKERRQ(ierr);\
130         ierr = PetscMemcpy(new_a+BS2*(AI[ROW]+NROW+CHUNKSIZE),AA+BS2*(AI[ROW]+NROW),BS2*len*sizeof(datatype));CHKERRQ(ierr);  \
131         /* free up old matrix storage */ \
132         ierr = MatSeqXAIJFreeAIJ(A,&Ain->a,&Ain->j,&Ain->i);CHKERRQ(ierr);\
133         AA = new_a; \
134         Ain->a = (MatScalar*) new_a;		   \
135         AI = Ain->i = new_i; AJ = Ain->j = new_j;  \
136         Ain->singlemalloc = PETSC_TRUE; \
137  \
138         RP          = AJ + AI[ROW]; AP = AA + BS2*AI[ROW]; \
139         RMAX        = AIMAX[ROW] = AIMAX[ROW] + CHUNKSIZE; \
140         Ain->maxnz += BS2*CHUNKSIZE; \
141         Ain->reallocs++; \
142       } \
143 
144 
145 EXTERN_C_BEGIN
146 EXTERN PetscErrorCode MatSeqAIJSetPreallocation_SeqAIJ(Mat,PetscInt,PetscInt*);
147 EXTERN_C_END
148 EXTERN PetscErrorCode MatILUFactorSymbolic_SeqAIJ_inplace(Mat,Mat,IS,IS,const MatFactorInfo*);
149 EXTERN PetscErrorCode MatILUFactorSymbolic_SeqAIJ(Mat,Mat,IS,IS,const MatFactorInfo*);
150 EXTERN PetscErrorCode MatILUFactorSymbolic_SeqAIJ_ilu0(Mat,Mat,IS,IS,const MatFactorInfo*);
151 
152 EXTERN PetscErrorCode MatICCFactorSymbolic_SeqAIJ_inplace(Mat,Mat,IS,const MatFactorInfo*);
153 EXTERN PetscErrorCode MatICCFactorSymbolic_SeqAIJ(Mat,Mat,IS,const MatFactorInfo*);
154 EXTERN PetscErrorCode MatCholeskyFactorSymbolic_SeqAIJ_inplace(Mat,Mat,IS,const MatFactorInfo*);
155 EXTERN PetscErrorCode MatCholeskyFactorSymbolic_SeqAIJ(Mat,Mat,IS,const MatFactorInfo*);
156 EXTERN PetscErrorCode MatCholeskyFactorNumeric_SeqAIJ_inplace(Mat,Mat,const MatFactorInfo*);
157 EXTERN PetscErrorCode MatCholeskyFactorNumeric_SeqAIJ(Mat,Mat,const MatFactorInfo*);
158 EXTERN PetscErrorCode MatDuplicate_SeqAIJ(Mat,MatDuplicateOption,Mat*);
159 EXTERN PetscErrorCode MatCopy_SeqAIJ(Mat,Mat,MatStructure);
160 EXTERN PetscErrorCode MatMissingDiagonal_SeqAIJ(Mat,PetscTruth*,PetscInt*);
161 EXTERN PetscErrorCode MatMarkDiagonal_SeqAIJ(Mat);
162 
163 EXTERN PetscErrorCode MatMult_SeqAIJ(Mat A,Vec,Vec);
164 EXTERN PetscErrorCode MatMultAdd_SeqAIJ(Mat A,Vec,Vec,Vec);
165 EXTERN PetscErrorCode MatMultTranspose_SeqAIJ(Mat A,Vec,Vec);
166 EXTERN PetscErrorCode MatMultTransposeAdd_SeqAIJ(Mat A,Vec,Vec,Vec);
167 EXTERN PetscErrorCode MatSOR_SeqAIJ(Mat,Vec,PetscReal,MatSORType,PetscReal,PetscInt,PetscInt,Vec);
168 
169 EXTERN PetscErrorCode MatSetColoring_SeqAIJ(Mat,ISColoring);
170 EXTERN PetscErrorCode MatSetValuesAdic_SeqAIJ(Mat,void*);
171 EXTERN PetscErrorCode MatSetValuesAdifor_SeqAIJ(Mat,PetscInt,void*);
172 
173 EXTERN PetscErrorCode MatGetSymbolicTranspose_SeqAIJ(Mat,PetscInt *[],PetscInt *[]);
174 EXTERN PetscErrorCode MatGetSymbolicTransposeReduced_SeqAIJ(Mat,PetscInt,PetscInt,PetscInt *[],PetscInt *[]);
175 EXTERN PetscErrorCode MatRestoreSymbolicTranspose_SeqAIJ(Mat,PetscInt *[],PetscInt *[]);
176 EXTERN PetscErrorCode MatToSymmetricIJ_SeqAIJ(PetscInt,PetscInt*,PetscInt*,PetscInt,PetscInt,PetscInt**,PetscInt**);
177 EXTERN PetscErrorCode MatLUFactorSymbolic_SeqAIJ_inplace(Mat,Mat,IS,IS,const MatFactorInfo*);
178 EXTERN PetscErrorCode MatLUFactorSymbolic_SeqAIJ(Mat,Mat,IS,IS,const MatFactorInfo*);
179 EXTERN PetscErrorCode MatLUFactorNumeric_SeqAIJ_inplace(Mat,Mat,const MatFactorInfo*);
180 EXTERN PetscErrorCode MatLUFactorNumeric_SeqAIJ(Mat,Mat,const MatFactorInfo*);
181 EXTERN PetscErrorCode MatLUFactorNumeric_SeqAIJ_InplaceWithPerm(Mat,Mat,const MatFactorInfo*);
182 EXTERN PetscErrorCode MatLUFactor_SeqAIJ(Mat,IS,IS,const MatFactorInfo*);
183 EXTERN PetscErrorCode MatSolve_SeqAIJ_inplace(Mat,Vec,Vec);
184 EXTERN PetscErrorCode MatSolve_SeqAIJ(Mat,Vec,Vec);
185 EXTERN PetscErrorCode MatSolve_SeqAIJ_Inode_inplace(Mat,Vec,Vec);
186 EXTERN PetscErrorCode MatSolve_SeqAIJ_Inode(Mat,Vec,Vec);
187 EXTERN PetscErrorCode MatSolve_SeqAIJ_NaturalOrdering_inplace(Mat,Vec,Vec);
188 EXTERN PetscErrorCode MatSolve_SeqAIJ_NaturalOrdering(Mat,Vec,Vec);
189 EXTERN PetscErrorCode MatSolve_SeqAIJ_InplaceWithPerm(Mat,Vec,Vec);
190 EXTERN PetscErrorCode MatSolveAdd_SeqAIJ_inplace(Mat,Vec,Vec,Vec);
191 EXTERN PetscErrorCode MatSolveAdd_SeqAIJ(Mat,Vec,Vec,Vec);
192 EXTERN PetscErrorCode MatSolveTranspose_SeqAIJ_inplace(Mat,Vec,Vec);
193 EXTERN PetscErrorCode MatSolveTranspose_SeqAIJ(Mat,Vec,Vec);
194 EXTERN PetscErrorCode MatSolveTransposeAdd_SeqAIJ_inplace(Mat,Vec,Vec,Vec);
195 EXTERN PetscErrorCode MatSolveTransposeAdd_SeqAIJ(Mat,Vec,Vec,Vec);
196 EXTERN PetscErrorCode MatMatSolve_SeqAIJ_inplace(Mat,Mat,Mat);
197 EXTERN PetscErrorCode MatMatSolve_SeqAIJ(Mat,Mat,Mat);
198 EXTERN PetscErrorCode MatEqual_SeqAIJ(Mat A,Mat B,PetscTruth* flg);
199 EXTERN PetscErrorCode MatFDColoringCreate_SeqAIJ(Mat,ISColoring,MatFDColoring);
200 EXTERN PetscErrorCode MatLoad_SeqAIJ(PetscViewer, const MatType,Mat*);
201 EXTERN PetscErrorCode MatLoadnew_SeqAIJ(PetscViewer,Mat);
202 EXTERN PetscErrorCode RegisterApplyPtAPRoutines_Private(Mat);
203 EXTERN PetscErrorCode MatMatMultSymbolic_SeqAIJ_SeqAIJ(Mat,Mat,PetscReal,Mat*);
204 EXTERN PetscErrorCode MatMatMultNumeric_SeqAIJ_SeqAIJ(Mat,Mat,Mat);
205 EXTERN PetscErrorCode MatPtAPSymbolic_SeqAIJ(Mat,Mat,PetscReal,Mat*);
206 EXTERN PetscErrorCode MatPtAPNumeric_SeqAIJ(Mat,Mat,Mat);
207 EXTERN PetscErrorCode MatPtAPSymbolic_SeqAIJ_SeqAIJ(Mat,Mat,PetscReal,Mat*);
208 EXTERN PetscErrorCode MatPtAPNumeric_SeqAIJ_SeqAIJ(Mat,Mat,Mat);
209 EXTERN PetscErrorCode MatMatMultTranspose_SeqAIJ_SeqAIJ(Mat,Mat,MatReuse,PetscReal,Mat*);
210 EXTERN PetscErrorCode MatMatMultTransposeSymbolic_SeqAIJ_SeqAIJ(Mat,Mat,PetscReal,Mat*);
211 EXTERN PetscErrorCode MatMatMultTransposeNumeric_SeqAIJ_SeqAIJ(Mat,Mat,Mat);
212 EXTERN PetscErrorCode MatSetValues_SeqAIJ(Mat,PetscInt,const PetscInt[],PetscInt,const PetscInt[],const PetscScalar[],InsertMode);
213 EXTERN PetscErrorCode MatGetRow_SeqAIJ(Mat,PetscInt,PetscInt*,PetscInt**,PetscScalar**);
214 EXTERN PetscErrorCode MatRestoreRow_SeqAIJ(Mat,PetscInt,PetscInt*,PetscInt**,PetscScalar**);
215 EXTERN PetscErrorCode MatAXPY_SeqAIJ(Mat,PetscScalar,Mat,MatStructure);
216 EXTERN PetscErrorCode MatGetRowIJ_SeqAIJ(Mat,PetscInt,PetscTruth,PetscTruth,PetscInt*,PetscInt *[],PetscInt *[],PetscTruth *);
217 EXTERN PetscErrorCode MatRestoreRowIJ_SeqAIJ(Mat,PetscInt,PetscTruth,PetscTruth,PetscInt *,PetscInt *[],PetscInt *[],PetscTruth *);
218 EXTERN PetscErrorCode MatGetColumnIJ_SeqAIJ(Mat,PetscInt,PetscTruth,PetscTruth,PetscInt*,PetscInt *[],PetscInt *[],PetscTruth *);
219 EXTERN PetscErrorCode MatRestoreColumnIJ_SeqAIJ(Mat,PetscInt,PetscTruth,PetscTruth,PetscInt *,PetscInt *[],PetscInt *[],PetscTruth *);
220 EXTERN PetscErrorCode MatDestroy_SeqAIJ(Mat);
221 EXTERN PetscErrorCode MatView_SeqAIJ(Mat,PetscViewer);
222 
223 EXTERN PetscErrorCode Mat_CheckInode(Mat,PetscTruth);
224 EXTERN PetscErrorCode Mat_CheckInode_FactorLU(Mat,PetscTruth);
225 
226 EXTERN_C_BEGIN
227 EXTERN PetscErrorCode PETSCMAT_DLLEXPORT MatConvert_SeqAIJ_SeqSBAIJ(Mat,const MatType,MatReuse,Mat*);
228 EXTERN PetscErrorCode PETSCMAT_DLLEXPORT MatConvert_SeqAIJ_SeqBAIJ(Mat,const MatType,MatReuse,Mat*);
229 EXTERN PetscErrorCode PETSCMAT_DLLEXPORT MatConvert_SeqAIJ_SeqCSRPERM(Mat,const MatType,MatReuse,Mat*);
230 EXTERN PetscErrorCode PETSCMAT_DLLEXPORT MatReorderForNonzeroDiagonal_SeqAIJ(Mat,PetscReal,IS,IS);
231 EXTERN PetscErrorCode PETSCMAT_DLLEXPORT MatMatMult_SeqAIJ_SeqAIJ(Mat,Mat,MatReuse,PetscReal,Mat*);
232 EXTERN_C_END
233 
234 /*
235     PetscSparseDenseMinusDot - The inner kernel of triangular solves and Gauss-Siedel smoothing. \sum_i xv[i] * r[xi[i]] for CSR storage
236 
237   Input Parameters:
238 +  nnz - the number of entries
239 .  r - the array of vector values
240 .  xv - the matrix values for the row
241 -  xi - the column indices of the nonzeros in the row
242 
243   Output Parameter:
244 .  sum - negative the sum of results
245 
246   PETSc compile flags:
247 +   PETSC_KERNEL_USE_UNROLL_4 -   don't use this; it changes nnz and hence is WRONG
248 -   PETSC_KERNEL_USE_UNROLL_2 -
249 
250 .seealso: PetscSparseDensePlusDot()
251 
252 */
253 #ifdef PETSC_KERNEL_USE_UNROLL_4
254 #define PetscSparseDenseMinusDot(sum,r,xv,xi,nnz) {\
255 if (nnz > 0) {\
256 switch (nnz & 0x3) {\
257 case 3: sum -= *xv++ * r[*xi++];\
258 case 2: sum -= *xv++ * r[*xi++];\
259 case 1: sum -= *xv++ * r[*xi++];\
260 nnz -= 4;}\
261 while (nnz > 0) {\
262 sum -=  xv[0] * r[xi[0]] - xv[1] * r[xi[1]] -\
263 	xv[2] * r[xi[2]] - xv[3] * r[xi[3]];\
264 xv  += 4; xi += 4; nnz -= 4; }}}
265 
266 #elif defined(PETSC_KERNEL_USE_UNROLL_2)
267 #define PetscSparseDenseMinusDot(sum,r,xv,xi,nnz) {\
268 PetscInt __i,__i1,__i2;\
269 for(__i=0;__i<nnz-1;__i+=2) {__i1 = xi[__i]; __i2=xi[__i+1];\
270 sum -= (xv[__i]*r[__i1] + xv[__i+1]*r[__i2]);}\
271 if (nnz & 0x1) sum -= xv[__i] * r[xi[__i]];}
272 
273 #else
274 #define PetscSparseDenseMinusDot(sum,r,xv,xi,nnz) {\
275 PetscInt __i;\
276 for(__i=0;__i<nnz;__i++) sum -= xv[__i] * r[xi[__i]];}
277 #endif
278 
279 
280 
281 /*
282     PetscSparseDensePlusDot - The inner kernel of matrix-vector product \sum_i xv[i] * r[xi[i]] for CSR storage
283 
284   Input Parameters:
285 +  nnz - the number of entries
286 .  r - the array of vector values
287 .  xv - the matrix values for the row
288 -  xi - the column indices of the nonzeros in the row
289 
290   Output Parameter:
291 .  sum - the sum of results
292 
293   PETSc compile flags:
294 +   PETSC_KERNEL_USE_UNROLL_4 -  don't use this; it changes nnz and hence is WRONG
295 -   PETSC_KERNEL_USE_UNROLL_2 -
296 
297 .seealso: PetscSparseDenseMinusDot()
298 
299 */
300 #ifdef PETSC_KERNEL_USE_UNROLL_4
301 #define PetscSparseDensePlusDot(sum,r,xv,xi,nnz) {\
302 if (nnz > 0) {\
303 switch (nnz & 0x3) {\
304 case 3: sum += *xv++ * r[*xi++];\
305 case 2: sum += *xv++ * r[*xi++];\
306 case 1: sum += *xv++ * r[*xi++];\
307 nnz -= 4;}\
308 while (nnz > 0) {\
309 sum +=  xv[0] * r[xi[0]] + xv[1] * r[xi[1]] +\
310 	xv[2] * r[xi[2]] + xv[3] * r[xi[3]];\
311 xv  += 4; xi += 4; nnz -= 4; }}}
312 
313 #elif defined(PETSC_KERNEL_USE_UNROLL_2)
314 #define PetscSparseDensePlusDot(sum,r,xv,xi,nnz) {\
315 PetscInt __i,__i1,__i2;\
316 for(__i=0;__i<nnz-1;__i+=2) {__i1 = xi[__i]; __i2=xi[__i+1];\
317 sum += (xv[__i]*r[__i1] + xv[__i+1]*r[__i2]);}\
318 if (nnz & 0x1) sum += xv[__i] * r[xi[__i]];}
319 
320 #else
321 #define PetscSparseDensePlusDot(sum,r,xv,xi,nnz) {\
322  PetscInt __i;\
323 for(__i=0;__i<nnz;__i++) sum += xv[__i] * r[xi[__i]];}
324 #endif
325 
326 #endif
327