xref: /petsc/src/mat/impls/aij/seq/inode.c (revision ce0a2cd1da0658c2b28aad1be2e2c8e41567bece)
1 #define PETSCMAT_DLL
2 
3 /*
4   This file provides high performance routines for the Inode format (compressed sparse row)
5   by taking advantage of rows with identical nonzero structure (I-nodes).
6 */
7 #include "src/mat/impls/aij/seq/aij.h"
8 
9 #undef __FUNCT__
10 #define __FUNCT__ "Mat_CreateColInode"
11 static PetscErrorCode Mat_CreateColInode(Mat A,PetscInt* size,PetscInt ** ns)
12 {
13   Mat_SeqAIJ      *a = (Mat_SeqAIJ*)A->data;
14   PetscErrorCode ierr;
15   PetscInt       i,count,m,n,min_mn,*ns_row,*ns_col;
16 
17   PetscFunctionBegin;
18   n      = A->cmap.n;
19   m      = A->rmap.n;
20   ns_row = a->inode.size;
21 
22   min_mn = (m < n) ? m : n;
23   if (!ns) {
24     for (count=0,i=0; count<min_mn; count+=ns_row[i],i++);
25     for(; count+1 < n; count++,i++);
26     if (count < n)  {
27       i++;
28     }
29     *size = i;
30     PetscFunctionReturn(0);
31   }
32   ierr = PetscMalloc((n+1)*sizeof(PetscInt),&ns_col);CHKERRQ(ierr);
33 
34   /* Use the same row structure wherever feasible. */
35   for (count=0,i=0; count<min_mn; count+=ns_row[i],i++) {
36     ns_col[i] = ns_row[i];
37   }
38 
39   /* if m < n; pad up the remainder with inode_limit */
40   for(; count+1 < n; count++,i++) {
41     ns_col[i] = 1;
42   }
43   /* The last node is the odd ball. padd it up with the remaining rows; */
44   if (count < n)  {
45     ns_col[i] = n - count;
46     i++;
47   } else if (count > n) {
48     /* Adjust for the over estimation */
49     ns_col[i-1] += n - count;
50   }
51   *size = i;
52   *ns   = ns_col;
53   PetscFunctionReturn(0);
54 }
55 
56 
57 /*
58       This builds symmetric version of nonzero structure,
59 */
60 #undef __FUNCT__
61 #define __FUNCT__ "MatGetRowIJ_Inode_Symmetric"
62 static PetscErrorCode MatGetRowIJ_Inode_Symmetric(Mat A,PetscInt *iia[],PetscInt *jja[],PetscInt ishift,PetscInt oshift)
63 {
64   Mat_SeqAIJ      *a = (Mat_SeqAIJ*)A->data;
65   PetscErrorCode ierr;
66   PetscInt       *work,*ia,*ja,*j,nz,nslim_row,nslim_col,m,row,col,*jmax,n;
67   PetscInt       *tns,*tvc,*ns_row = a->inode.size,*ns_col,nsz,i1,i2,*ai= a->i,*aj = a->j;
68 
69   PetscFunctionBegin;
70   nslim_row = a->inode.node_count;
71   m         = A->rmap.n;
72   n         = A->cmap.n;
73   if (m != n) SETERRQ(PETSC_ERR_SUP,"MatGetRowIJ_Inode_Symmetric: Matrix should be square");
74 
75   /* Use the row_inode as column_inode */
76   nslim_col = nslim_row;
77   ns_col    = ns_row;
78 
79   /* allocate space for reformated inode structure */
80   ierr = PetscMalloc((nslim_col+1)*sizeof(PetscInt),&tns);CHKERRQ(ierr);
81   ierr = PetscMalloc((n+1)*sizeof(PetscInt),&tvc);CHKERRQ(ierr);
82   for (i1=0,tns[0]=0; i1<nslim_col; ++i1) tns[i1+1] = tns[i1]+ ns_row[i1];
83 
84   for (i1=0,col=0; i1<nslim_col; ++i1){
85     nsz = ns_col[i1];
86     for (i2=0; i2<nsz; ++i2,++col)
87       tvc[col] = i1;
88   }
89   /* allocate space for row pointers */
90   ierr = PetscMalloc((nslim_row+1)*sizeof(PetscInt),&ia);CHKERRQ(ierr);
91   *iia = ia;
92   ierr = PetscMemzero(ia,(nslim_row+1)*sizeof(PetscInt));CHKERRQ(ierr);
93   ierr = PetscMalloc((nslim_row+1)*sizeof(PetscInt),&work);CHKERRQ(ierr);
94 
95   /* determine the number of columns in each row */
96   ia[0] = oshift;
97   for (i1=0,row=0 ; i1<nslim_row; row+=ns_row[i1],i1++) {
98 
99     j    = aj + ai[row] + ishift;
100     jmax = aj + ai[row+1] + ishift;
101     i2   = 0;
102     col  = *j++ + ishift;
103     i2   = tvc[col];
104     while (i2<i1 && j<jmax) { /* 1.[-xx-d-xx--] 2.[-xx-------],off-diagonal elemets */
105       ia[i1+1]++;
106       ia[i2+1]++;
107       i2++;                     /* Start col of next node */
108       while(((col=*j+ishift)<tns[i2]) && (j<jmax)) ++j;
109       i2 = tvc[col];
110     }
111     if(i2 == i1) ia[i2+1]++;    /* now the diagonal element */
112   }
113 
114   /* shift ia[i] to point to next row */
115   for (i1=1; i1<nslim_row+1; i1++) {
116     row        = ia[i1-1];
117     ia[i1]    += row;
118     work[i1-1] = row - oshift;
119   }
120 
121   /* allocate space for column pointers */
122   nz   = ia[nslim_row] + (!ishift);
123   ierr = PetscMalloc(nz*sizeof(PetscInt),&ja);CHKERRQ(ierr);
124   *jja = ja;
125 
126  /* loop over lower triangular part putting into ja */
127   for (i1=0,row=0; i1<nslim_row; row += ns_row[i1],i1++) {
128     j    = aj + ai[row] + ishift;
129     jmax = aj + ai[row+1] + ishift;
130     i2   = 0;                     /* Col inode index */
131     col  = *j++ + ishift;
132     i2   = tvc[col];
133     while (i2<i1 && j<jmax) {
134       ja[work[i2]++] = i1 + oshift;
135       ja[work[i1]++] = i2 + oshift;
136       ++i2;
137       while(((col=*j+ishift)< tns[i2])&&(j<jmax)) ++j; /* Skip rest col indices in this node */
138       i2 = tvc[col];
139     }
140     if (i2 == i1) ja[work[i1]++] = i2 + oshift;
141 
142   }
143   ierr = PetscFree(work);CHKERRQ(ierr);
144   ierr = PetscFree(tns);CHKERRQ(ierr);
145   ierr = PetscFree(tvc);CHKERRQ(ierr);
146   PetscFunctionReturn(0);
147 }
148 
149 /*
150       This builds nonsymmetric version of nonzero structure,
151 */
152 #undef __FUNCT__
153 #define __FUNCT__ "MatGetRowIJ_Inode_Nonsymmetric"
154 static PetscErrorCode MatGetRowIJ_Inode_Nonsymmetric(Mat A,PetscInt *iia[],PetscInt *jja[],PetscInt ishift,PetscInt oshift)
155 {
156   Mat_SeqAIJ      *a = (Mat_SeqAIJ*)A->data;
157   PetscErrorCode ierr;
158   PetscInt       *work,*ia,*ja,*j,nz,nslim_row,n,row,col,*ns_col,nslim_col;
159   PetscInt       *tns,*tvc,*ns_row = a->inode.size,nsz,i1,i2,*ai= a->i,*aj = a->j;
160 
161   PetscFunctionBegin;
162   nslim_row = a->inode.node_count;
163   n         = A->cmap.n;
164 
165   /* Create The column_inode for this matrix */
166   ierr = Mat_CreateColInode(A,&nslim_col,&ns_col);CHKERRQ(ierr);
167 
168   /* allocate space for reformated column_inode structure */
169   ierr = PetscMalloc((nslim_col +1)*sizeof(PetscInt),&tns);CHKERRQ(ierr);
170   ierr = PetscMalloc((n +1)*sizeof(PetscInt),&tvc);CHKERRQ(ierr);
171   for (i1=0,tns[0]=0; i1<nslim_col; ++i1) tns[i1+1] = tns[i1] + ns_col[i1];
172 
173   for (i1=0,col=0; i1<nslim_col; ++i1){
174     nsz = ns_col[i1];
175     for (i2=0; i2<nsz; ++i2,++col)
176       tvc[col] = i1;
177   }
178   /* allocate space for row pointers */
179   ierr = PetscMalloc((nslim_row+1)*sizeof(PetscInt),&ia);CHKERRQ(ierr);
180   *iia = ia;
181   ierr = PetscMemzero(ia,(nslim_row+1)*sizeof(PetscInt));CHKERRQ(ierr);
182   ierr = PetscMalloc((nslim_row+1)*sizeof(PetscInt),&work);CHKERRQ(ierr);
183 
184   /* determine the number of columns in each row */
185   ia[0] = oshift;
186   for (i1=0,row=0; i1<nslim_row; row+=ns_row[i1],i1++) {
187     j   = aj + ai[row] + ishift;
188     col = *j++ + ishift;
189     i2  = tvc[col];
190     nz  = ai[row+1] - ai[row];
191     while (nz-- > 0) {           /* off-diagonal elemets */
192       ia[i1+1]++;
193       i2++;                     /* Start col of next node */
194       while (((col = *j++ + ishift) < tns[i2]) && nz > 0) {nz--;}
195       if (nz > 0) i2 = tvc[col];
196     }
197   }
198 
199   /* shift ia[i] to point to next row */
200   for (i1=1; i1<nslim_row+1; i1++) {
201     row        = ia[i1-1];
202     ia[i1]    += row;
203     work[i1-1] = row - oshift;
204   }
205 
206   /* allocate space for column pointers */
207   nz   = ia[nslim_row] + (!ishift);
208   ierr = PetscMalloc(nz*sizeof(PetscInt),&ja);CHKERRQ(ierr);
209   *jja = ja;
210 
211  /* loop over matrix putting into ja */
212   for (i1=0,row=0; i1<nslim_row; row+=ns_row[i1],i1++) {
213     j   = aj + ai[row] + ishift;
214     i2  = 0;                     /* Col inode index */
215     col = *j++ + ishift;
216     i2  = tvc[col];
217     nz  = ai[row+1] - ai[row];
218     while (nz-- > 0) {
219       ja[work[i1]++] = i2 + oshift;
220       ++i2;
221       while(((col = *j++ + ishift) < tns[i2]) && nz > 0) {nz--;}
222       if (nz > 0) i2 = tvc[col];
223     }
224   }
225   ierr = PetscFree(ns_col);CHKERRQ(ierr);
226   ierr = PetscFree(work);CHKERRQ(ierr);
227   ierr = PetscFree(tns);CHKERRQ(ierr);
228   ierr = PetscFree(tvc);CHKERRQ(ierr);
229   PetscFunctionReturn(0);
230 }
231 
232 #undef __FUNCT__
233 #define __FUNCT__ "MatGetRowIJ_Inode"
234 static PetscErrorCode MatGetRowIJ_Inode(Mat A,PetscInt oshift,PetscTruth symmetric,PetscTruth blockcompressed,PetscInt *n,PetscInt *ia[],PetscInt *ja[],PetscTruth *done)
235 {
236   Mat_SeqAIJ      *a = (Mat_SeqAIJ*)A->data;
237   PetscErrorCode ierr;
238 
239   PetscFunctionBegin;
240   *n     = a->inode.node_count;
241   if (!ia) PetscFunctionReturn(0);
242   if (!blockcompressed) {
243     ierr = MatGetRowIJ_SeqAIJ(A,oshift,symmetric,blockcompressed,n,ia,ja,done);CHKERRQ(ierr);;
244   } else if (symmetric) {
245     ierr = MatGetRowIJ_Inode_Symmetric(A,ia,ja,0,oshift);CHKERRQ(ierr);
246   } else {
247     ierr = MatGetRowIJ_Inode_Nonsymmetric(A,ia,ja,0,oshift);CHKERRQ(ierr);
248   }
249   PetscFunctionReturn(0);
250 }
251 
252 #undef __FUNCT__
253 #define __FUNCT__ "MatRestoreRowIJ_Inode"
254 static PetscErrorCode MatRestoreRowIJ_Inode(Mat A,PetscInt oshift,PetscTruth symmetric,PetscTruth blockcompressed,PetscInt *n,PetscInt *ia[],PetscInt *ja[],PetscTruth *done)
255 {
256   PetscErrorCode ierr;
257 
258   PetscFunctionBegin;
259   if (!ia) PetscFunctionReturn(0);
260 
261   if (!blockcompressed) {
262     ierr = MatRestoreRowIJ_SeqAIJ(A,oshift,symmetric,blockcompressed,n,ia,ja,done);CHKERRQ(ierr);;
263   } else {
264     ierr = PetscFree(*ia);CHKERRQ(ierr);
265     ierr = PetscFree(*ja);CHKERRQ(ierr);
266   }
267 
268   PetscFunctionReturn(0);
269 }
270 
271 /* ----------------------------------------------------------- */
272 
273 #undef __FUNCT__
274 #define __FUNCT__ "MatGetColumnIJ_Inode_Nonsymmetric"
275 static PetscErrorCode MatGetColumnIJ_Inode_Nonsymmetric(Mat A,PetscInt *iia[],PetscInt *jja[],PetscInt ishift,PetscInt oshift)
276 {
277   Mat_SeqAIJ      *a = (Mat_SeqAIJ*)A->data;
278   PetscErrorCode ierr;
279   PetscInt       *work,*ia,*ja,*j,nz,nslim_row, n,row,col,*ns_col,nslim_col;
280   PetscInt       *tns,*tvc,*ns_row = a->inode.size,nsz,i1,i2,*ai= a->i,*aj = a->j;
281 
282   PetscFunctionBegin;
283   nslim_row = a->inode.node_count;
284   n         = A->cmap.n;
285 
286   /* Create The column_inode for this matrix */
287   ierr = Mat_CreateColInode(A,&nslim_col,&ns_col);CHKERRQ(ierr);
288 
289   /* allocate space for reformated column_inode structure */
290   ierr = PetscMalloc((nslim_col + 1)*sizeof(PetscInt),&tns);CHKERRQ(ierr);
291   ierr = PetscMalloc((n + 1)*sizeof(PetscInt),&tvc);CHKERRQ(ierr);
292   for (i1=0,tns[0]=0; i1<nslim_col; ++i1) tns[i1+1] = tns[i1] + ns_col[i1];
293 
294   for (i1=0,col=0; i1<nslim_col; ++i1){
295     nsz = ns_col[i1];
296     for (i2=0; i2<nsz; ++i2,++col)
297       tvc[col] = i1;
298   }
299   /* allocate space for column pointers */
300   ierr = PetscMalloc((nslim_col+1)*sizeof(PetscInt),&ia);CHKERRQ(ierr);
301   *iia = ia;
302   ierr = PetscMemzero(ia,(nslim_col+1)*sizeof(PetscInt));CHKERRQ(ierr);
303   ierr = PetscMalloc((nslim_col+1)*sizeof(PetscInt),&work);CHKERRQ(ierr);
304 
305   /* determine the number of columns in each row */
306   ia[0] = oshift;
307   for (i1=0,row=0; i1<nslim_row; row+=ns_row[i1],i1++) {
308     j   = aj + ai[row] + ishift;
309     col = *j++ + ishift;
310     i2  = tvc[col];
311     nz  = ai[row+1] - ai[row];
312     while (nz-- > 0) {           /* off-diagonal elemets */
313       /* ia[i1+1]++; */
314       ia[i2+1]++;
315       i2++;
316       while (((col = *j++ + ishift) < tns[i2]) && nz > 0) {nz--;}
317       if (nz > 0) i2 = tvc[col];
318     }
319   }
320 
321   /* shift ia[i] to point to next col */
322   for (i1=1; i1<nslim_col+1; i1++) {
323     col        = ia[i1-1];
324     ia[i1]    += col;
325     work[i1-1] = col - oshift;
326   }
327 
328   /* allocate space for column pointers */
329   nz   = ia[nslim_col] + (!ishift);
330   ierr = PetscMalloc(nz*sizeof(PetscInt),&ja);CHKERRQ(ierr);
331   *jja = ja;
332 
333  /* loop over matrix putting into ja */
334   for (i1=0,row=0; i1<nslim_row; row+=ns_row[i1],i1++) {
335     j   = aj + ai[row] + ishift;
336     i2  = 0;                     /* Col inode index */
337     col = *j++ + ishift;
338     i2  = tvc[col];
339     nz  = ai[row+1] - ai[row];
340     while (nz-- > 0) {
341       /* ja[work[i1]++] = i2 + oshift; */
342       ja[work[i2]++] = i1 + oshift;
343       i2++;
344       while(((col = *j++ + ishift) < tns[i2]) && nz > 0) {nz--;}
345       if (nz > 0) i2 = tvc[col];
346     }
347   }
348   ierr = PetscFree(ns_col);CHKERRQ(ierr);
349   ierr = PetscFree(work);CHKERRQ(ierr);
350   ierr = PetscFree(tns);CHKERRQ(ierr);
351   ierr = PetscFree(tvc);CHKERRQ(ierr);
352   PetscFunctionReturn(0);
353 }
354 
355 #undef __FUNCT__
356 #define __FUNCT__ "MatGetColumnIJ_Inode"
357 static PetscErrorCode MatGetColumnIJ_Inode(Mat A,PetscInt oshift,PetscTruth symmetric,PetscTruth blockcompressed,PetscInt *n,PetscInt *ia[],PetscInt *ja[],PetscTruth *done)
358 {
359   PetscErrorCode ierr;
360 
361   PetscFunctionBegin;
362   ierr = Mat_CreateColInode(A,n,PETSC_NULL);CHKERRQ(ierr);
363   if (!ia) PetscFunctionReturn(0);
364 
365   if (!blockcompressed) {
366     ierr = MatGetColumnIJ_SeqAIJ(A,oshift,symmetric,blockcompressed,n,ia,ja,done);CHKERRQ(ierr);;
367   } else if (symmetric) {
368     /* Since the indices are symmetric it does'nt matter */
369     ierr = MatGetRowIJ_Inode_Symmetric(A,ia,ja,0,oshift);CHKERRQ(ierr);
370   } else {
371     ierr = MatGetColumnIJ_Inode_Nonsymmetric(A,ia,ja,0,oshift);CHKERRQ(ierr);
372   }
373   PetscFunctionReturn(0);
374 }
375 
376 #undef __FUNCT__
377 #define __FUNCT__ "MatRestoreColumnIJ_Inode"
378 static PetscErrorCode MatRestoreColumnIJ_Inode(Mat A,PetscInt oshift,PetscTruth symmetric,PetscTruth blockcompressed,PetscInt *n,PetscInt *ia[],PetscInt *ja[],PetscTruth *done)
379 {
380   PetscErrorCode ierr;
381 
382   PetscFunctionBegin;
383   if (!ia) PetscFunctionReturn(0);
384   if (!blockcompressed) {
385     ierr = MatRestoreColumnIJ_SeqAIJ(A,oshift,symmetric,blockcompressed,n,ia,ja,done);CHKERRQ(ierr);;
386   } else {
387     ierr = PetscFree(*ia);CHKERRQ(ierr);
388     ierr = PetscFree(*ja);CHKERRQ(ierr);
389   }
390   PetscFunctionReturn(0);
391 }
392 
393 /* ----------------------------------------------------------- */
394 
395 #undef __FUNCT__
396 #define __FUNCT__ "MatMult_Inode"
397 static PetscErrorCode MatMult_Inode(Mat A,Vec xx,Vec yy)
398 {
399   Mat_SeqAIJ        *a = (Mat_SeqAIJ*)A->data;
400   PetscScalar       sum1,sum2,sum3,sum4,sum5,tmp0,tmp1;
401   PetscScalar       *y;
402   const PetscScalar *x;
403   const MatScalar   *v1,*v2,*v3,*v4,*v5;
404   PetscErrorCode    ierr;
405   PetscInt          *idx,i1,i2,n,i,row,node_max,*ns,*ii,nsz,sz,nonzerorow=0;
406 
407 #if defined(PETSC_HAVE_PRAGMA_DISJOINT)
408 #pragma disjoint(*x,*y,*v1,*v2,*v3,*v4,*v5)
409 #endif
410 
411   PetscFunctionBegin;
412   if (!a->inode.size) SETERRQ(PETSC_ERR_COR,"Missing Inode Structure");
413   node_max = a->inode.node_count;
414   ns       = a->inode.size;     /* Node Size array */
415   ierr = VecGetArray(xx,(PetscScalar**)&x);CHKERRQ(ierr);
416   ierr = VecGetArray(yy,&y);CHKERRQ(ierr);
417   idx  = a->j;
418   v1   = a->a;
419   ii   = a->i;
420 
421   for (i = 0,row = 0; i< node_max; ++i){
422     nsz  = ns[i];
423     n    = ii[1] - ii[0];
424     nonzerorow += (n>0)*nsz;
425     ii  += nsz;
426     sz   = n;                   /* No of non zeros in this row */
427                                 /* Switch on the size of Node */
428     switch (nsz){               /* Each loop in 'case' is unrolled */
429     case 1 :
430       sum1  = 0;
431 
432       for(n = 0; n< sz-1; n+=2) {
433         i1   = idx[0];          /* The instructions are ordered to */
434         i2   = idx[1];          /* make the compiler's job easy */
435         idx += 2;
436         tmp0 = x[i1];
437         tmp1 = x[i2];
438         sum1 += v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
439        }
440 
441       if (n == sz-1){          /* Take care of the last nonzero  */
442         tmp0  = x[*idx++];
443         sum1 += *v1++ * tmp0;
444       }
445       y[row++]=sum1;
446       break;
447     case 2:
448       sum1  = 0;
449       sum2  = 0;
450       v2    = v1 + n;
451 
452       for (n = 0; n< sz-1; n+=2) {
453         i1   = idx[0];
454         i2   = idx[1];
455         idx += 2;
456         tmp0 = x[i1];
457         tmp1 = x[i2];
458         sum1 += v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
459         sum2 += v2[0] * tmp0 + v2[1] * tmp1; v2 += 2;
460       }
461       if (n == sz-1){
462         tmp0  = x[*idx++];
463         sum1 += *v1++ * tmp0;
464         sum2 += *v2++ * tmp0;
465       }
466       y[row++]=sum1;
467       y[row++]=sum2;
468       v1      =v2;              /* Since the next block to be processed starts there*/
469       idx    +=sz;
470       break;
471     case 3:
472       sum1  = 0;
473       sum2  = 0;
474       sum3  = 0;
475       v2    = v1 + n;
476       v3    = v2 + n;
477 
478       for (n = 0; n< sz-1; n+=2) {
479         i1   = idx[0];
480         i2   = idx[1];
481         idx += 2;
482         tmp0 = x[i1];
483         tmp1 = x[i2];
484         sum1 += v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
485         sum2 += v2[0] * tmp0 + v2[1] * tmp1; v2 += 2;
486         sum3 += v3[0] * tmp0 + v3[1] * tmp1; v3 += 2;
487       }
488       if (n == sz-1){
489         tmp0  = x[*idx++];
490         sum1 += *v1++ * tmp0;
491         sum2 += *v2++ * tmp0;
492         sum3 += *v3++ * tmp0;
493       }
494       y[row++]=sum1;
495       y[row++]=sum2;
496       y[row++]=sum3;
497       v1       =v3;             /* Since the next block to be processed starts there*/
498       idx     +=2*sz;
499       break;
500     case 4:
501       sum1  = 0;
502       sum2  = 0;
503       sum3  = 0;
504       sum4  = 0;
505       v2    = v1 + n;
506       v3    = v2 + n;
507       v4    = v3 + n;
508 
509       for (n = 0; n< sz-1; n+=2) {
510         i1   = idx[0];
511         i2   = idx[1];
512         idx += 2;
513         tmp0 = x[i1];
514         tmp1 = x[i2];
515         sum1 += v1[0] * tmp0 + v1[1] *tmp1; v1 += 2;
516         sum2 += v2[0] * tmp0 + v2[1] *tmp1; v2 += 2;
517         sum3 += v3[0] * tmp0 + v3[1] *tmp1; v3 += 2;
518         sum4 += v4[0] * tmp0 + v4[1] *tmp1; v4 += 2;
519       }
520       if (n == sz-1){
521         tmp0  = x[*idx++];
522         sum1 += *v1++ * tmp0;
523         sum2 += *v2++ * tmp0;
524         sum3 += *v3++ * tmp0;
525         sum4 += *v4++ * tmp0;
526       }
527       y[row++]=sum1;
528       y[row++]=sum2;
529       y[row++]=sum3;
530       y[row++]=sum4;
531       v1      =v4;              /* Since the next block to be processed starts there*/
532       idx    +=3*sz;
533       break;
534     case 5:
535       sum1  = 0;
536       sum2  = 0;
537       sum3  = 0;
538       sum4  = 0;
539       sum5  = 0;
540       v2    = v1 + n;
541       v3    = v2 + n;
542       v4    = v3 + n;
543       v5    = v4 + n;
544 
545       for (n = 0; n<sz-1; n+=2) {
546         i1   = idx[0];
547         i2   = idx[1];
548         idx += 2;
549         tmp0 = x[i1];
550         tmp1 = x[i2];
551         sum1 += v1[0] * tmp0 + v1[1] *tmp1; v1 += 2;
552         sum2 += v2[0] * tmp0 + v2[1] *tmp1; v2 += 2;
553         sum3 += v3[0] * tmp0 + v3[1] *tmp1; v3 += 2;
554         sum4 += v4[0] * tmp0 + v4[1] *tmp1; v4 += 2;
555         sum5 += v5[0] * tmp0 + v5[1] *tmp1; v5 += 2;
556       }
557       if (n == sz-1){
558         tmp0  = x[*idx++];
559         sum1 += *v1++ * tmp0;
560         sum2 += *v2++ * tmp0;
561         sum3 += *v3++ * tmp0;
562         sum4 += *v4++ * tmp0;
563         sum5 += *v5++ * tmp0;
564       }
565       y[row++]=sum1;
566       y[row++]=sum2;
567       y[row++]=sum3;
568       y[row++]=sum4;
569       y[row++]=sum5;
570       v1      =v5;       /* Since the next block to be processed starts there */
571       idx    +=4*sz;
572       break;
573     default :
574       SETERRQ(PETSC_ERR_COR,"Node size not yet supported");
575     }
576   }
577   ierr = VecRestoreArray(xx,(PetscScalar**)&x);CHKERRQ(ierr);
578   ierr = VecRestoreArray(yy,&y);CHKERRQ(ierr);
579   ierr = PetscLogFlops(2*a->nz - nonzerorow);CHKERRQ(ierr);
580   PetscFunctionReturn(0);
581 }
582 /* ----------------------------------------------------------- */
583 /* Almost same code as the MatMult_Inode() */
584 #undef __FUNCT__
585 #define __FUNCT__ "MatMultAdd_Inode"
586 static PetscErrorCode MatMultAdd_Inode(Mat A,Vec xx,Vec zz,Vec yy)
587 {
588   Mat_SeqAIJ      *a = (Mat_SeqAIJ*)A->data;
589   PetscScalar    sum1,sum2,sum3,sum4,sum5,tmp0,tmp1;
590   MatScalar      *v1,*v2,*v3,*v4,*v5;
591   PetscScalar    *x,*y,*z,*zt;
592   PetscErrorCode ierr;
593   PetscInt       *idx,i1,i2,n,i,row,node_max,*ns,*ii,nsz,sz;
594 
595   PetscFunctionBegin;
596   if (!a->inode.size) SETERRQ(PETSC_ERR_COR,"Missing Inode Structure");
597   node_max = a->inode.node_count;
598   ns       = a->inode.size;     /* Node Size array */
599   ierr = VecGetArray(xx,&x);CHKERRQ(ierr);
600   ierr = VecGetArray(yy,&y);CHKERRQ(ierr);
601   if (zz != yy) {
602     ierr = VecGetArray(zz,&z);CHKERRQ(ierr);
603   } else {
604     z = y;
605   }
606   zt = z;
607 
608   idx  = a->j;
609   v1   = a->a;
610   ii   = a->i;
611 
612   for (i = 0,row = 0; i< node_max; ++i){
613     nsz  = ns[i];
614     n    = ii[1] - ii[0];
615     ii  += nsz;
616     sz   = n;                   /* No of non zeros in this row */
617                                 /* Switch on the size of Node */
618     switch (nsz){               /* Each loop in 'case' is unrolled */
619     case 1 :
620       sum1  = *zt++;
621 
622       for(n = 0; n< sz-1; n+=2) {
623         i1   = idx[0];          /* The instructions are ordered to */
624         i2   = idx[1];          /* make the compiler's job easy */
625         idx += 2;
626         tmp0 = x[i1];
627         tmp1 = x[i2];
628         sum1 += v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
629        }
630 
631       if(n   == sz-1){          /* Take care of the last nonzero  */
632         tmp0  = x[*idx++];
633         sum1 += *v1++ * tmp0;
634       }
635       y[row++]=sum1;
636       break;
637     case 2:
638       sum1  = *zt++;
639       sum2  = *zt++;
640       v2    = v1 + n;
641 
642       for(n = 0; n< sz-1; n+=2) {
643         i1   = idx[0];
644         i2   = idx[1];
645         idx += 2;
646         tmp0 = x[i1];
647         tmp1 = x[i2];
648         sum1 += v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
649         sum2 += v2[0] * tmp0 + v2[1] * tmp1; v2 += 2;
650       }
651       if(n   == sz-1){
652         tmp0  = x[*idx++];
653         sum1 += *v1++ * tmp0;
654         sum2 += *v2++ * tmp0;
655       }
656       y[row++]=sum1;
657       y[row++]=sum2;
658       v1      =v2;              /* Since the next block to be processed starts there*/
659       idx    +=sz;
660       break;
661     case 3:
662       sum1  = *zt++;
663       sum2  = *zt++;
664       sum3  = *zt++;
665       v2    = v1 + n;
666       v3    = v2 + n;
667 
668       for (n = 0; n< sz-1; n+=2) {
669         i1   = idx[0];
670         i2   = idx[1];
671         idx += 2;
672         tmp0 = x[i1];
673         tmp1 = x[i2];
674         sum1 += v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
675         sum2 += v2[0] * tmp0 + v2[1] * tmp1; v2 += 2;
676         sum3 += v3[0] * tmp0 + v3[1] * tmp1; v3 += 2;
677       }
678       if (n == sz-1){
679         tmp0  = x[*idx++];
680         sum1 += *v1++ * tmp0;
681         sum2 += *v2++ * tmp0;
682         sum3 += *v3++ * tmp0;
683       }
684       y[row++]=sum1;
685       y[row++]=sum2;
686       y[row++]=sum3;
687       v1       =v3;             /* Since the next block to be processed starts there*/
688       idx     +=2*sz;
689       break;
690     case 4:
691       sum1  = *zt++;
692       sum2  = *zt++;
693       sum3  = *zt++;
694       sum4  = *zt++;
695       v2    = v1 + n;
696       v3    = v2 + n;
697       v4    = v3 + n;
698 
699       for (n = 0; n< sz-1; n+=2) {
700         i1   = idx[0];
701         i2   = idx[1];
702         idx += 2;
703         tmp0 = x[i1];
704         tmp1 = x[i2];
705         sum1 += v1[0] * tmp0 + v1[1] *tmp1; v1 += 2;
706         sum2 += v2[0] * tmp0 + v2[1] *tmp1; v2 += 2;
707         sum3 += v3[0] * tmp0 + v3[1] *tmp1; v3 += 2;
708         sum4 += v4[0] * tmp0 + v4[1] *tmp1; v4 += 2;
709       }
710       if (n == sz-1){
711         tmp0  = x[*idx++];
712         sum1 += *v1++ * tmp0;
713         sum2 += *v2++ * tmp0;
714         sum3 += *v3++ * tmp0;
715         sum4 += *v4++ * tmp0;
716       }
717       y[row++]=sum1;
718       y[row++]=sum2;
719       y[row++]=sum3;
720       y[row++]=sum4;
721       v1      =v4;              /* Since the next block to be processed starts there*/
722       idx    +=3*sz;
723       break;
724     case 5:
725       sum1  = *zt++;
726       sum2  = *zt++;
727       sum3  = *zt++;
728       sum4  = *zt++;
729       sum5  = *zt++;
730       v2    = v1 + n;
731       v3    = v2 + n;
732       v4    = v3 + n;
733       v5    = v4 + n;
734 
735       for (n = 0; n<sz-1; n+=2) {
736         i1   = idx[0];
737         i2   = idx[1];
738         idx += 2;
739         tmp0 = x[i1];
740         tmp1 = x[i2];
741         sum1 += v1[0] * tmp0 + v1[1] *tmp1; v1 += 2;
742         sum2 += v2[0] * tmp0 + v2[1] *tmp1; v2 += 2;
743         sum3 += v3[0] * tmp0 + v3[1] *tmp1; v3 += 2;
744         sum4 += v4[0] * tmp0 + v4[1] *tmp1; v4 += 2;
745         sum5 += v5[0] * tmp0 + v5[1] *tmp1; v5 += 2;
746       }
747       if(n   == sz-1){
748         tmp0  = x[*idx++];
749         sum1 += *v1++ * tmp0;
750         sum2 += *v2++ * tmp0;
751         sum3 += *v3++ * tmp0;
752         sum4 += *v4++ * tmp0;
753         sum5 += *v5++ * tmp0;
754       }
755       y[row++]=sum1;
756       y[row++]=sum2;
757       y[row++]=sum3;
758       y[row++]=sum4;
759       y[row++]=sum5;
760       v1      =v5;       /* Since the next block to be processed starts there */
761       idx    +=4*sz;
762       break;
763     default :
764       SETERRQ(PETSC_ERR_COR,"Node size not yet supported");
765     }
766   }
767   ierr = VecRestoreArray(xx,&x);CHKERRQ(ierr);
768   ierr = VecRestoreArray(yy,&y);CHKERRQ(ierr);
769   if (zz != yy) {
770     ierr = VecRestoreArray(zz,&z);CHKERRQ(ierr);
771   }
772   ierr = PetscLogFlops(2*a->nz);CHKERRQ(ierr);
773   PetscFunctionReturn(0);
774 }
775 
776 /* ----------------------------------------------------------- */
777 #undef __FUNCT__
778 #define __FUNCT__ "MatSolve_Inode"
779 PetscErrorCode MatSolve_Inode(Mat A,Vec bb,Vec xx)
780 {
781   Mat_SeqAIJ        *a = (Mat_SeqAIJ*)A->data;
782   IS                iscol = a->col,isrow = a->row;
783   PetscErrorCode    ierr;
784   PetscInt          *r,*c,i,j,n = A->rmap.n,*ai = a->i,nz,*a_j = a->j;
785   PetscInt          node_max,*ns,row,nsz,aii,*vi,*ad,*aj,i0,i1,*rout,*cout;
786   PetscScalar       *x,*tmp,*tmps,tmp0,tmp1;
787   PetscScalar       sum1,sum2,sum3,sum4,sum5;
788   const MatScalar   *v1,*v2,*v3,*v4,*v5,*a_a = a->a,*aa;
789   const PetscScalar *b;
790 
791   PetscFunctionBegin;
792   if (A->factor!=FACTOR_LU) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unfactored matrix");
793   if (!a->inode.size) SETERRQ(PETSC_ERR_COR,"Missing Inode Structure");
794   node_max = a->inode.node_count;
795   ns       = a->inode.size;     /* Node Size array */
796 
797   ierr = VecGetArray(bb,(PetscScalar**)&b);CHKERRQ(ierr);
798   ierr = VecGetArray(xx,&x);CHKERRQ(ierr);
799   tmp  = a->solve_work;
800 
801   ierr = ISGetIndices(isrow,&rout);CHKERRQ(ierr); r = rout;
802   ierr = ISGetIndices(iscol,&cout);CHKERRQ(ierr); c = cout + (n-1);
803 
804   /* forward solve the lower triangular */
805   tmps = tmp ;
806   aa   = a_a ;
807   aj   = a_j ;
808   ad   = a->diag;
809 
810   for (i = 0,row = 0; i< node_max; ++i){
811     nsz = ns[i];
812     aii = ai[row];
813     v1  = aa + aii;
814     vi  = aj + aii;
815     nz  = ad[row]- aii;
816 
817     switch (nsz){               /* Each loop in 'case' is unrolled */
818     case 1 :
819       sum1 = b[*r++];
820       /*      while (nz--) sum1 -= *v1++ *tmps[*vi++];*/
821       for(j=0; j<nz-1; j+=2){
822         i0   = vi[0];
823         i1   = vi[1];
824         vi  +=2;
825         tmp0 = tmps[i0];
826         tmp1 = tmps[i1];
827         sum1 -= v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
828       }
829       if(j == nz-1){
830         tmp0 = tmps[*vi++];
831         sum1 -= *v1++ *tmp0;
832       }
833       tmp[row ++]=sum1;
834       break;
835     case 2:
836       sum1 = b[*r++];
837       sum2 = b[*r++];
838       v2   = aa + ai[row+1];
839 
840       for(j=0; j<nz-1; j+=2){
841         i0   = vi[0];
842         i1   = vi[1];
843         vi  +=2;
844         tmp0 = tmps[i0];
845         tmp1 = tmps[i1];
846         sum1 -= v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
847         sum2 -= v2[0] * tmp0 + v2[1] * tmp1; v2 += 2;
848       }
849       if(j == nz-1){
850         tmp0 = tmps[*vi++];
851         sum1 -= *v1++ *tmp0;
852         sum2 -= *v2++ *tmp0;
853       }
854       sum2 -= *v2++ * sum1;
855       tmp[row ++]=sum1;
856       tmp[row ++]=sum2;
857       break;
858     case 3:
859       sum1 = b[*r++];
860       sum2 = b[*r++];
861       sum3 = b[*r++];
862       v2   = aa + ai[row+1];
863       v3   = aa + ai[row+2];
864 
865       for (j=0; j<nz-1; j+=2){
866         i0   = vi[0];
867         i1   = vi[1];
868         vi  +=2;
869         tmp0 = tmps[i0];
870         tmp1 = tmps[i1];
871         sum1 -= v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
872         sum2 -= v2[0] * tmp0 + v2[1] * tmp1; v2 += 2;
873         sum3 -= v3[0] * tmp0 + v3[1] * tmp1; v3 += 2;
874       }
875       if (j == nz-1){
876         tmp0 = tmps[*vi++];
877         sum1 -= *v1++ *tmp0;
878         sum2 -= *v2++ *tmp0;
879         sum3 -= *v3++ *tmp0;
880       }
881       sum2 -= *v2++ * sum1;
882       sum3 -= *v3++ * sum1;
883       sum3 -= *v3++ * sum2;
884       tmp[row ++]=sum1;
885       tmp[row ++]=sum2;
886       tmp[row ++]=sum3;
887       break;
888 
889     case 4:
890       sum1 = b[*r++];
891       sum2 = b[*r++];
892       sum3 = b[*r++];
893       sum4 = b[*r++];
894       v2   = aa + ai[row+1];
895       v3   = aa + ai[row+2];
896       v4   = aa + ai[row+3];
897 
898       for (j=0; j<nz-1; j+=2){
899         i0   = vi[0];
900         i1   = vi[1];
901         vi  +=2;
902         tmp0 = tmps[i0];
903         tmp1 = tmps[i1];
904         sum1 -= v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
905         sum2 -= v2[0] * tmp0 + v2[1] * tmp1; v2 += 2;
906         sum3 -= v3[0] * tmp0 + v3[1] * tmp1; v3 += 2;
907         sum4 -= v4[0] * tmp0 + v4[1] * tmp1; v4 += 2;
908       }
909       if (j == nz-1){
910         tmp0 = tmps[*vi++];
911         sum1 -= *v1++ *tmp0;
912         sum2 -= *v2++ *tmp0;
913         sum3 -= *v3++ *tmp0;
914         sum4 -= *v4++ *tmp0;
915       }
916       sum2 -= *v2++ * sum1;
917       sum3 -= *v3++ * sum1;
918       sum4 -= *v4++ * sum1;
919       sum3 -= *v3++ * sum2;
920       sum4 -= *v4++ * sum2;
921       sum4 -= *v4++ * sum3;
922 
923       tmp[row ++]=sum1;
924       tmp[row ++]=sum2;
925       tmp[row ++]=sum3;
926       tmp[row ++]=sum4;
927       break;
928     case 5:
929       sum1 = b[*r++];
930       sum2 = b[*r++];
931       sum3 = b[*r++];
932       sum4 = b[*r++];
933       sum5 = b[*r++];
934       v2   = aa + ai[row+1];
935       v3   = aa + ai[row+2];
936       v4   = aa + ai[row+3];
937       v5   = aa + ai[row+4];
938 
939       for (j=0; j<nz-1; j+=2){
940         i0   = vi[0];
941         i1   = vi[1];
942         vi  +=2;
943         tmp0 = tmps[i0];
944         tmp1 = tmps[i1];
945         sum1 -= v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
946         sum2 -= v2[0] * tmp0 + v2[1] * tmp1; v2 += 2;
947         sum3 -= v3[0] * tmp0 + v3[1] * tmp1; v3 += 2;
948         sum4 -= v4[0] * tmp0 + v4[1] * tmp1; v4 += 2;
949         sum5 -= v5[0] * tmp0 + v5[1] * tmp1; v5 += 2;
950       }
951       if (j == nz-1){
952         tmp0 = tmps[*vi++];
953         sum1 -= *v1++ *tmp0;
954         sum2 -= *v2++ *tmp0;
955         sum3 -= *v3++ *tmp0;
956         sum4 -= *v4++ *tmp0;
957         sum5 -= *v5++ *tmp0;
958       }
959 
960       sum2 -= *v2++ * sum1;
961       sum3 -= *v3++ * sum1;
962       sum4 -= *v4++ * sum1;
963       sum5 -= *v5++ * sum1;
964       sum3 -= *v3++ * sum2;
965       sum4 -= *v4++ * sum2;
966       sum5 -= *v5++ * sum2;
967       sum4 -= *v4++ * sum3;
968       sum5 -= *v5++ * sum3;
969       sum5 -= *v5++ * sum4;
970 
971       tmp[row ++]=sum1;
972       tmp[row ++]=sum2;
973       tmp[row ++]=sum3;
974       tmp[row ++]=sum4;
975       tmp[row ++]=sum5;
976       break;
977     default:
978       SETERRQ(PETSC_ERR_COR,"Node size not yet supported \n");
979     }
980   }
981   /* backward solve the upper triangular */
982   for (i=node_max -1 ,row = n-1 ; i>=0; i--){
983     nsz = ns[i];
984     aii = ai[row+1] -1;
985     v1  = aa + aii;
986     vi  = aj + aii;
987     nz  = aii- ad[row];
988     switch (nsz){               /* Each loop in 'case' is unrolled */
989     case 1 :
990       sum1 = tmp[row];
991 
992       for(j=nz ; j>1; j-=2){
993         vi  -=2;
994         i0   = vi[2];
995         i1   = vi[1];
996         tmp0 = tmps[i0];
997         tmp1 = tmps[i1];
998         v1   -= 2;
999         sum1 -= v1[2] * tmp0 + v1[1] * tmp1;
1000       }
1001       if (j==1){
1002         tmp0  = tmps[*vi--];
1003         sum1 -= *v1-- * tmp0;
1004       }
1005       x[*c--] = tmp[row] = sum1*a_a[ad[row]]; row--;
1006       break;
1007     case 2 :
1008       sum1 = tmp[row];
1009       sum2 = tmp[row -1];
1010       v2   = aa + ai[row]-1;
1011       for (j=nz ; j>1; j-=2){
1012         vi  -=2;
1013         i0   = vi[2];
1014         i1   = vi[1];
1015         tmp0 = tmps[i0];
1016         tmp1 = tmps[i1];
1017         v1   -= 2;
1018         v2   -= 2;
1019         sum1 -= v1[2] * tmp0 + v1[1] * tmp1;
1020         sum2 -= v2[2] * tmp0 + v2[1] * tmp1;
1021       }
1022       if (j==1){
1023         tmp0  = tmps[*vi--];
1024         sum1 -= *v1-- * tmp0;
1025         sum2 -= *v2-- * tmp0;
1026       }
1027 
1028       tmp0    = x[*c--] = tmp[row] = sum1*a_a[ad[row]]; row--;
1029       sum2   -= *v2-- * tmp0;
1030       x[*c--] = tmp[row] = sum2*a_a[ad[row]]; row--;
1031       break;
1032     case 3 :
1033       sum1 = tmp[row];
1034       sum2 = tmp[row -1];
1035       sum3 = tmp[row -2];
1036       v2   = aa + ai[row]-1;
1037       v3   = aa + ai[row -1]-1;
1038       for (j=nz ; j>1; j-=2){
1039         vi  -=2;
1040         i0   = vi[2];
1041         i1   = vi[1];
1042         tmp0 = tmps[i0];
1043         tmp1 = tmps[i1];
1044         v1   -= 2;
1045         v2   -= 2;
1046         v3   -= 2;
1047         sum1 -= v1[2] * tmp0 + v1[1] * tmp1;
1048         sum2 -= v2[2] * tmp0 + v2[1] * tmp1;
1049         sum3 -= v3[2] * tmp0 + v3[1] * tmp1;
1050       }
1051       if (j==1){
1052         tmp0  = tmps[*vi--];
1053         sum1 -= *v1-- * tmp0;
1054         sum2 -= *v2-- * tmp0;
1055         sum3 -= *v3-- * tmp0;
1056       }
1057       tmp0    = x[*c--] = tmp[row] = sum1*a_a[ad[row]]; row--;
1058       sum2   -= *v2-- * tmp0;
1059       sum3   -= *v3-- * tmp0;
1060       tmp0    = x[*c--] = tmp[row] = sum2*a_a[ad[row]]; row--;
1061       sum3   -= *v3-- * tmp0;
1062       x[*c--] = tmp[row] = sum3*a_a[ad[row]]; row--;
1063 
1064       break;
1065     case 4 :
1066       sum1 = tmp[row];
1067       sum2 = tmp[row -1];
1068       sum3 = tmp[row -2];
1069       sum4 = tmp[row -3];
1070       v2   = aa + ai[row]-1;
1071       v3   = aa + ai[row -1]-1;
1072       v4   = aa + ai[row -2]-1;
1073 
1074       for (j=nz ; j>1; j-=2){
1075         vi  -=2;
1076         i0   = vi[2];
1077         i1   = vi[1];
1078         tmp0 = tmps[i0];
1079         tmp1 = tmps[i1];
1080         v1  -= 2;
1081         v2  -= 2;
1082         v3  -= 2;
1083         v4  -= 2;
1084         sum1 -= v1[2] * tmp0 + v1[1] * tmp1;
1085         sum2 -= v2[2] * tmp0 + v2[1] * tmp1;
1086         sum3 -= v3[2] * tmp0 + v3[1] * tmp1;
1087         sum4 -= v4[2] * tmp0 + v4[1] * tmp1;
1088       }
1089       if (j==1){
1090         tmp0  = tmps[*vi--];
1091         sum1 -= *v1-- * tmp0;
1092         sum2 -= *v2-- * tmp0;
1093         sum3 -= *v3-- * tmp0;
1094         sum4 -= *v4-- * tmp0;
1095       }
1096 
1097       tmp0    = x[*c--] = tmp[row] = sum1*a_a[ad[row]]; row--;
1098       sum2   -= *v2-- * tmp0;
1099       sum3   -= *v3-- * tmp0;
1100       sum4   -= *v4-- * tmp0;
1101       tmp0    = x[*c--] = tmp[row] = sum2*a_a[ad[row]]; row--;
1102       sum3   -= *v3-- * tmp0;
1103       sum4   -= *v4-- * tmp0;
1104       tmp0    = x[*c--] = tmp[row] = sum3*a_a[ad[row]]; row--;
1105       sum4   -= *v4-- * tmp0;
1106       x[*c--] = tmp[row] = sum4*a_a[ad[row]]; row--;
1107       break;
1108     case 5 :
1109       sum1 = tmp[row];
1110       sum2 = tmp[row -1];
1111       sum3 = tmp[row -2];
1112       sum4 = tmp[row -3];
1113       sum5 = tmp[row -4];
1114       v2   = aa + ai[row]-1;
1115       v3   = aa + ai[row -1]-1;
1116       v4   = aa + ai[row -2]-1;
1117       v5   = aa + ai[row -3]-1;
1118       for (j=nz ; j>1; j-=2){
1119         vi  -= 2;
1120         i0   = vi[2];
1121         i1   = vi[1];
1122         tmp0 = tmps[i0];
1123         tmp1 = tmps[i1];
1124         v1   -= 2;
1125         v2   -= 2;
1126         v3   -= 2;
1127         v4   -= 2;
1128         v5   -= 2;
1129         sum1 -= v1[2] * tmp0 + v1[1] * tmp1;
1130         sum2 -= v2[2] * tmp0 + v2[1] * tmp1;
1131         sum3 -= v3[2] * tmp0 + v3[1] * tmp1;
1132         sum4 -= v4[2] * tmp0 + v4[1] * tmp1;
1133         sum5 -= v5[2] * tmp0 + v5[1] * tmp1;
1134       }
1135       if (j==1){
1136         tmp0  = tmps[*vi--];
1137         sum1 -= *v1-- * tmp0;
1138         sum2 -= *v2-- * tmp0;
1139         sum3 -= *v3-- * tmp0;
1140         sum4 -= *v4-- * tmp0;
1141         sum5 -= *v5-- * tmp0;
1142       }
1143 
1144       tmp0    = x[*c--] = tmp[row] = sum1*a_a[ad[row]]; row--;
1145       sum2   -= *v2-- * tmp0;
1146       sum3   -= *v3-- * tmp0;
1147       sum4   -= *v4-- * tmp0;
1148       sum5   -= *v5-- * tmp0;
1149       tmp0    = x[*c--] = tmp[row] = sum2*a_a[ad[row]]; row--;
1150       sum3   -= *v3-- * tmp0;
1151       sum4   -= *v4-- * tmp0;
1152       sum5   -= *v5-- * tmp0;
1153       tmp0    = x[*c--] = tmp[row] = sum3*a_a[ad[row]]; row--;
1154       sum4   -= *v4-- * tmp0;
1155       sum5   -= *v5-- * tmp0;
1156       tmp0    = x[*c--] = tmp[row] = sum4*a_a[ad[row]]; row--;
1157       sum5   -= *v5-- * tmp0;
1158       x[*c--] = tmp[row] = sum5*a_a[ad[row]]; row--;
1159       break;
1160     default:
1161       SETERRQ(PETSC_ERR_COR,"Node size not yet supported \n");
1162     }
1163   }
1164   ierr = ISRestoreIndices(isrow,&rout);CHKERRQ(ierr);
1165   ierr = ISRestoreIndices(iscol,&cout);CHKERRQ(ierr);
1166   ierr = VecRestoreArray(bb,(PetscScalar**)&b);CHKERRQ(ierr);
1167   ierr = VecRestoreArray(xx,&x);CHKERRQ(ierr);
1168   ierr = PetscLogFlops(2*a->nz - A->cmap.n);CHKERRQ(ierr);
1169   PetscFunctionReturn(0);
1170 }
1171 
1172 #undef __FUNCT__
1173 #define __FUNCT__ "MatLUFactorNumeric_Inode"
1174 PetscErrorCode MatLUFactorNumeric_Inode(Mat A,MatFactorInfo *info,Mat *B)
1175 {
1176   Mat               C = *B;
1177   Mat_SeqAIJ        *a = (Mat_SeqAIJ*)A->data,*b = (Mat_SeqAIJ*)C->data;
1178   IS                iscol = b->col,isrow = b->row,isicol = b->icol;
1179   PetscErrorCode    ierr;
1180   PetscInt          *r,*ic,*c,n = A->rmap.n,*bi = b->i;
1181   PetscInt          *bj = b->j,*nbj=b->j +1,*ajtmp,*bjtmp,nz,nz_tmp,row,prow;
1182   PetscInt          *ics,i,j,idx,*ai = a->i,*aj = a->j,*bd = b->diag,node_max,nodesz;
1183   PetscInt          *ns,*tmp_vec1,*tmp_vec2,*nsmap,*pj;
1184   PetscScalar       mul1,mul2,mul3,tmp;
1185   MatScalar         *pc1,*pc2,*pc3,*ba = b->a,*pv,*rtmp11,*rtmp22,*rtmp33;
1186   const MatScalar   *v1,*v2,*v3,*aa = a->a,*rtmp1;
1187   PetscReal         rs=0.0;
1188   LUShift_Ctx       sctx;
1189   PetscInt          newshift;
1190 
1191   PetscFunctionBegin;
1192   sctx.shift_top  = 0;
1193   sctx.nshift_max = 0;
1194   sctx.shift_lo   = 0;
1195   sctx.shift_hi   = 0;
1196 
1197   /* if both shift schemes are chosen by user, only use info->shiftpd */
1198   if (info->shiftpd && info->shiftnz) info->shiftnz = 0.0;
1199   if (info->shiftpd) { /* set sctx.shift_top=max{rs} */
1200     sctx.shift_top = 0;
1201     for (i=0; i<n; i++) {
1202       /* calculate rs = sum(|aij|)-RealPart(aii), amt of shift needed for this row */
1203       rs    = 0.0;
1204       ajtmp = aj + ai[i];
1205       rtmp1 = aa + ai[i];
1206       nz = ai[i+1] - ai[i];
1207       for (j=0; j<nz; j++){
1208         if (*ajtmp != i){
1209           rs += PetscAbsScalar(*rtmp1++);
1210         } else {
1211           rs -= PetscRealPart(*rtmp1++);
1212         }
1213         ajtmp++;
1214       }
1215       if (rs>sctx.shift_top) sctx.shift_top = rs;
1216     }
1217     if (sctx.shift_top == 0.0) sctx.shift_top += 1.e-12;
1218     sctx.shift_top *= 1.1;
1219     sctx.nshift_max = 5;
1220     sctx.shift_lo   = 0.;
1221     sctx.shift_hi   = 1.;
1222   }
1223   sctx.shift_amount = 0;
1224   sctx.nshift       = 0;
1225 
1226   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
1227   ierr  = ISGetIndices(iscol,&c);CHKERRQ(ierr);
1228   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
1229   ierr  = PetscMalloc((3*n+1)*sizeof(PetscScalar),&rtmp11);CHKERRQ(ierr);
1230   ierr  = PetscMemzero(rtmp11,(3*n+1)*sizeof(PetscScalar));CHKERRQ(ierr);
1231   ics   = ic ;
1232   rtmp22 = rtmp11 + n;
1233   rtmp33 = rtmp22 + n;
1234 
1235   node_max = a->inode.node_count;
1236   ns       = a->inode.size ;
1237   if (!ns){
1238     SETERRQ(PETSC_ERR_PLIB,"Matrix without inode information");
1239   }
1240 
1241   /* If max inode size > 3, split it into two inodes.*/
1242   /* also map the inode sizes according to the ordering */
1243   ierr = PetscMalloc((n+1)* sizeof(PetscInt),&tmp_vec1);CHKERRQ(ierr);
1244   for (i=0,j=0; i<node_max; ++i,++j){
1245     if (ns[i]>3) {
1246       tmp_vec1[j] = ns[i]/2; /* Assuming ns[i] < =5  */
1247       ++j;
1248       tmp_vec1[j] = ns[i] - tmp_vec1[j-1];
1249     } else {
1250       tmp_vec1[j] = ns[i];
1251     }
1252   }
1253   /* Use the correct node_max */
1254   node_max = j;
1255 
1256   /* Now reorder the inode info based on mat re-ordering info */
1257   /* First create a row -> inode_size_array_index map */
1258   ierr = PetscMalloc(n*sizeof(PetscInt)+1,&nsmap);CHKERRQ(ierr);
1259   ierr = PetscMalloc(node_max*sizeof(PetscInt)+1,&tmp_vec2);CHKERRQ(ierr);
1260   for (i=0,row=0; i<node_max; i++) {
1261     nodesz = tmp_vec1[i];
1262     for (j=0; j<nodesz; j++,row++) {
1263       nsmap[row] = i;
1264     }
1265   }
1266   /* Using nsmap, create a reordered ns structure */
1267   for (i=0,j=0; i< node_max; i++) {
1268     nodesz       = tmp_vec1[nsmap[r[j]]];    /* here the reordered row_no is in r[] */
1269     tmp_vec2[i]  = nodesz;
1270     j           += nodesz;
1271   }
1272   ierr = PetscFree(nsmap);CHKERRQ(ierr);
1273   ierr = PetscFree(tmp_vec1);CHKERRQ(ierr);
1274   /* Now use the correct ns */
1275   ns = tmp_vec2;
1276 
1277   do {
1278     sctx.lushift = PETSC_FALSE;
1279     /* Now loop over each block-row, and do the factorization */
1280     for (i=0,row=0; i<node_max; i++) {
1281       nodesz = ns[i];
1282       nz     = bi[row+1] - bi[row];
1283       bjtmp  = bj + bi[row];
1284 
1285       switch (nodesz){
1286       case 1:
1287         for  (j=0; j<nz; j++){
1288           idx        = bjtmp[j];
1289           rtmp11[idx] = 0.0;
1290         }
1291 
1292         /* load in initial (unfactored row) */
1293         idx    = r[row];
1294         nz_tmp = ai[idx+1] - ai[idx];
1295         ajtmp  = aj + ai[idx];
1296         v1     = aa + ai[idx];
1297 
1298         for (j=0; j<nz_tmp; j++) {
1299           idx        = ics[ajtmp[j]];
1300           rtmp11[idx] = v1[j];
1301         }
1302         rtmp11[ics[r[row]]] += sctx.shift_amount;
1303 
1304         prow = *bjtmp++ ;
1305         while (prow < row) {
1306           pc1 = rtmp11 + prow;
1307           if (*pc1 != 0.0){
1308             pv   = ba + bd[prow];
1309             pj   = nbj + bd[prow];
1310             mul1 = *pc1 * *pv++;
1311             *pc1 = mul1;
1312             nz_tmp = bi[prow+1] - bd[prow] - 1;
1313             ierr = PetscLogFlops(2*nz_tmp);CHKERRQ(ierr);
1314             for (j=0; j<nz_tmp; j++) {
1315               tmp = pv[j];
1316               idx = pj[j];
1317               rtmp11[idx] -= mul1 * tmp;
1318             }
1319           }
1320           prow = *bjtmp++ ;
1321         }
1322         pj  = bj + bi[row];
1323         pc1 = ba + bi[row];
1324 
1325         sctx.pv    = rtmp11[row];
1326         rtmp11[row] = 1.0/rtmp11[row]; /* invert diag */
1327         rs         = 0.0;
1328         for (j=0; j<nz; j++) {
1329           idx    = pj[j];
1330           pc1[j] = rtmp11[idx]; /* rtmp11 -> ba */
1331           if (idx != row) rs += PetscAbsScalar(pc1[j]);
1332         }
1333         sctx.rs  = rs;
1334         ierr = MatLUCheckShift_inline(info,sctx,row,newshift);CHKERRQ(ierr);
1335         if (newshift == 1) goto endofwhile;
1336         break;
1337 
1338       case 2:
1339         for (j=0; j<nz; j++) {
1340           idx        = bjtmp[j];
1341           rtmp11[idx] = 0.0;
1342           rtmp22[idx] = 0.0;
1343         }
1344 
1345         /* load in initial (unfactored row) */
1346         idx    = r[row];
1347         nz_tmp = ai[idx+1] - ai[idx];
1348         ajtmp  = aj + ai[idx];
1349         v1     = aa + ai[idx];
1350         v2     = aa + ai[idx+1];
1351         for (j=0; j<nz_tmp; j++) {
1352           idx        = ics[ajtmp[j]];
1353           rtmp11[idx] = v1[j];
1354           rtmp22[idx] = v2[j];
1355         }
1356         rtmp11[ics[r[row]]]   += sctx.shift_amount;
1357         rtmp22[ics[r[row+1]]] += sctx.shift_amount;
1358 
1359         prow = *bjtmp++ ;
1360         while (prow < row) {
1361           pc1 = rtmp11 + prow;
1362           pc2 = rtmp22 + prow;
1363           if (*pc1 != 0.0 || *pc2 != 0.0){
1364             pv   = ba + bd[prow];
1365             pj   = nbj + bd[prow];
1366             mul1 = *pc1 * *pv;
1367             mul2 = *pc2 * *pv;
1368             ++pv;
1369             *pc1 = mul1;
1370             *pc2 = mul2;
1371 
1372             nz_tmp = bi[prow+1] - bd[prow] - 1;
1373             for (j=0; j<nz_tmp; j++) {
1374               tmp = pv[j];
1375               idx = pj[j];
1376               rtmp11[idx] -= mul1 * tmp;
1377               rtmp22[idx] -= mul2 * tmp;
1378             }
1379             ierr = PetscLogFlops(4*nz_tmp);CHKERRQ(ierr);
1380           }
1381           prow = *bjtmp++ ;
1382         }
1383 
1384         /* Now take care of diagonal 2x2 block. Note: prow = row here */
1385         pc1 = rtmp11 + prow;
1386         pc2 = rtmp22 + prow;
1387 
1388         sctx.pv = *pc1;
1389         pj      = bj + bi[prow];
1390         rs      = 0.0;
1391         for (j=0; j<nz; j++){
1392           idx = pj[j];
1393           if (idx != prow) rs += PetscAbsScalar(rtmp11[idx]);
1394         }
1395         sctx.rs = rs;
1396         ierr = MatLUCheckShift_inline(info,sctx,row,newshift);CHKERRQ(ierr);
1397         if (newshift == 1) goto endofwhile;
1398 
1399         if (*pc2 != 0.0){
1400           pj     = nbj + bd[prow];
1401           mul2   = (*pc2)/(*pc1); /* since diag is not yet inverted.*/
1402           *pc2   = mul2;
1403           nz_tmp = bi[prow+1] - bd[prow] - 1;
1404           for (j=0; j<nz_tmp; j++) {
1405             idx = pj[j] ;
1406             tmp = rtmp11[idx];
1407             rtmp22[idx] -= mul2 * tmp;
1408           }
1409           ierr = PetscLogFlops(2*nz_tmp);CHKERRQ(ierr);
1410         }
1411 
1412         pj  = bj + bi[row];
1413         pc1 = ba + bi[row];
1414         pc2 = ba + bi[row+1];
1415 
1416         sctx.pv = rtmp22[row+1];
1417         rs = 0.0;
1418         rtmp11[row]   = 1.0/rtmp11[row];
1419         rtmp22[row+1] = 1.0/rtmp22[row+1];
1420         /* copy row entries from dense representation to sparse */
1421         for (j=0; j<nz; j++) {
1422           idx    = pj[j];
1423           pc1[j] = rtmp11[idx];
1424           pc2[j] = rtmp22[idx];
1425           if (idx != row+1) rs += PetscAbsScalar(pc2[j]);
1426         }
1427         sctx.rs = rs;
1428         ierr = MatLUCheckShift_inline(info,sctx,row+1,newshift);CHKERRQ(ierr);
1429         if (newshift == 1) goto endofwhile;
1430         break;
1431 
1432       case 3:
1433         for  (j=0; j<nz; j++) {
1434           idx        = bjtmp[j];
1435           rtmp11[idx] = 0.0;
1436           rtmp22[idx] = 0.0;
1437           rtmp33[idx] = 0.0;
1438         }
1439         /* copy the nonzeros for the 3 rows from sparse representation to dense in rtmp*[] */
1440         idx    = r[row];
1441         nz_tmp = ai[idx+1] - ai[idx];
1442         ajtmp = aj + ai[idx];
1443         v1    = aa + ai[idx];
1444         v2    = aa + ai[idx+1];
1445         v3    = aa + ai[idx+2];
1446         for (j=0; j<nz_tmp; j++) {
1447           idx        = ics[ajtmp[j]];
1448           rtmp11[idx] = v1[j];
1449           rtmp22[idx] = v2[j];
1450           rtmp33[idx] = v3[j];
1451         }
1452         rtmp11[ics[r[row]]]   += sctx.shift_amount;
1453         rtmp22[ics[r[row+1]]] += sctx.shift_amount;
1454         rtmp33[ics[r[row+2]]] += sctx.shift_amount;
1455 
1456         /* loop over all pivot row blocks above this row block */
1457         prow = *bjtmp++ ;
1458         while (prow < row) {
1459           pc1 = rtmp11 + prow;
1460           pc2 = rtmp22 + prow;
1461           pc3 = rtmp33 + prow;
1462           if (*pc1 != 0.0 || *pc2 != 0.0 || *pc3 !=0.0){
1463             pv   = ba  + bd[prow];
1464             pj   = nbj + bd[prow];
1465             mul1 = *pc1 * *pv;
1466             mul2 = *pc2 * *pv;
1467             mul3 = *pc3 * *pv;
1468             ++pv;
1469             *pc1 = mul1;
1470             *pc2 = mul2;
1471             *pc3 = mul3;
1472 
1473             nz_tmp = bi[prow+1] - bd[prow] - 1;
1474             /* update this row based on pivot row */
1475             for (j=0; j<nz_tmp; j++) {
1476               tmp = pv[j];
1477               idx = pj[j];
1478               rtmp11[idx] -= mul1 * tmp;
1479               rtmp22[idx] -= mul2 * tmp;
1480               rtmp33[idx] -= mul3 * tmp;
1481             }
1482             ierr = PetscLogFlops(6*nz_tmp);CHKERRQ(ierr);
1483           }
1484           prow = *bjtmp++ ;
1485         }
1486 
1487         /* Now take care of diagonal 3x3 block in this set of rows */
1488         /* note: prow = row here */
1489         pc1 = rtmp11 + prow;
1490         pc2 = rtmp22 + prow;
1491         pc3 = rtmp33 + prow;
1492 
1493         sctx.pv = *pc1;
1494         pj      = bj + bi[prow];
1495         rs      = 0.0;
1496         for (j=0; j<nz; j++){
1497           idx = pj[j];
1498           if (idx != row) rs += PetscAbsScalar(rtmp11[idx]);
1499         }
1500         sctx.rs = rs;
1501         ierr = MatLUCheckShift_inline(info,sctx,row,newshift);CHKERRQ(ierr);
1502         if (newshift == 1) goto endofwhile;
1503 
1504         if (*pc2 != 0.0 || *pc3 != 0.0){
1505           mul2 = (*pc2)/(*pc1);
1506           mul3 = (*pc3)/(*pc1);
1507           *pc2 = mul2;
1508           *pc3 = mul3;
1509           nz_tmp = bi[prow+1] - bd[prow] - 1;
1510           pj     = nbj + bd[prow];
1511           for (j=0; j<nz_tmp; j++) {
1512             idx = pj[j] ;
1513             tmp = rtmp11[idx];
1514             rtmp22[idx] -= mul2 * tmp;
1515             rtmp33[idx] -= mul3 * tmp;
1516           }
1517           ierr = PetscLogFlops(4*nz_tmp);CHKERRQ(ierr);
1518         }
1519         ++prow;
1520 
1521         pc2 = rtmp22 + prow;
1522         pc3 = rtmp33 + prow;
1523         sctx.pv = *pc2;
1524         pj      = bj + bi[prow];
1525         rs      = 0.0;
1526         for (j=0; j<nz; j++){
1527           idx = pj[j];
1528           if (idx != prow) rs += PetscAbsScalar(rtmp22[idx]);
1529         }
1530         sctx.rs = rs;
1531         ierr = MatLUCheckShift_inline(info,sctx,row+1,newshift);CHKERRQ(ierr);
1532         if (newshift == 1) goto endofwhile;
1533 
1534         if (*pc3 != 0.0){
1535           mul3   = (*pc3)/(*pc2);
1536           *pc3   = mul3;
1537           pj     = nbj + bd[prow];
1538           nz_tmp = bi[prow+1] - bd[prow] - 1;
1539           for (j=0; j<nz_tmp; j++) {
1540             idx = pj[j] ;
1541             tmp = rtmp22[idx];
1542             rtmp33[idx] -= mul3 * tmp;
1543           }
1544           ierr = PetscLogFlops(4*nz_tmp);CHKERRQ(ierr);
1545         }
1546 
1547         pj  = bj + bi[row];
1548         pc1 = ba + bi[row];
1549         pc2 = ba + bi[row+1];
1550         pc3 = ba + bi[row+2];
1551 
1552         sctx.pv = rtmp33[row+2];
1553         rs = 0.0;
1554         rtmp11[row]   = 1.0/rtmp11[row];
1555         rtmp22[row+1] = 1.0/rtmp22[row+1];
1556         rtmp33[row+2] = 1.0/rtmp33[row+2];
1557         /* copy row entries from dense representation to sparse */
1558         for (j=0; j<nz; j++) {
1559           idx    = pj[j];
1560           pc1[j] = rtmp11[idx];
1561           pc2[j] = rtmp22[idx];
1562           pc3[j] = rtmp33[idx];
1563           if (idx != row+2) rs += PetscAbsScalar(pc3[j]);
1564         }
1565 
1566         sctx.rs = rs;
1567         ierr = MatLUCheckShift_inline(info,sctx,row+2,newshift);CHKERRQ(ierr);
1568         if (newshift == 1) goto endofwhile;
1569         break;
1570 
1571       default:
1572         SETERRQ(PETSC_ERR_COR,"Node size not yet supported \n");
1573       }
1574       row += nodesz;                 /* Update the row */
1575     }
1576     endofwhile:;
1577   } while (sctx.lushift);
1578   ierr = PetscFree(rtmp11);CHKERRQ(ierr);
1579   ierr = PetscFree(tmp_vec2);CHKERRQ(ierr);
1580   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
1581   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
1582   ierr = ISRestoreIndices(iscol,&c);CHKERRQ(ierr);
1583   C->factor      = FACTOR_LU;
1584   C->assembled   = PETSC_TRUE;
1585   if (sctx.nshift) {
1586     if (info->shiftnz) {
1587       ierr = PetscInfo2(A,"number of shift_nz tries %D, shift_amount %G\n",sctx.nshift,sctx.shift_amount);CHKERRQ(ierr);
1588     } else if (info->shiftpd) {
1589       ierr = PetscInfo4(A,"number of shift_pd tries %D, shift_amount %G, diagonal shifted up by %e fraction top_value %e\n",sctx.nshift,sctx.shift_amount,info->shift_fraction,sctx.shift_top);CHKERRQ(ierr);
1590     }
1591   }
1592   ierr = PetscLogFlops(C->cmap.n);CHKERRQ(ierr);
1593   PetscFunctionReturn(0);
1594 }
1595 
1596 /*
1597      Makes a longer coloring[] array and calls the usual code with that
1598 */
1599 #undef __FUNCT__
1600 #define __FUNCT__ "MatColoringPatch_Inode"
1601 PetscErrorCode MatColoringPatch_Inode(Mat mat,PetscInt ncolors,PetscInt nin,ISColoringValue coloring[],ISColoring *iscoloring)
1602 {
1603   Mat_SeqAIJ       *a = (Mat_SeqAIJ*)mat->data;
1604   PetscErrorCode  ierr;
1605   PetscInt        n = mat->cmap.n,m = a->inode.node_count,j,*ns = a->inode.size,row;
1606   PetscInt        *colorused,i;
1607   ISColoringValue *newcolor;
1608 
1609   PetscFunctionBegin;
1610   ierr = PetscMalloc((n+1)*sizeof(PetscInt),&newcolor);CHKERRQ(ierr);
1611   /* loop over inodes, marking a color for each column*/
1612   row = 0;
1613   for (i=0; i<m; i++){
1614     for (j=0; j<ns[i]; j++) {
1615       newcolor[row++] = coloring[i] + j*ncolors;
1616     }
1617   }
1618 
1619   /* eliminate unneeded colors */
1620   ierr = PetscMalloc(5*ncolors*sizeof(PetscInt),&colorused);CHKERRQ(ierr);
1621   ierr = PetscMemzero(colorused,5*ncolors*sizeof(PetscInt));CHKERRQ(ierr);
1622   for (i=0; i<n; i++) {
1623     colorused[newcolor[i]] = 1;
1624   }
1625 
1626   for (i=1; i<5*ncolors; i++) {
1627     colorused[i] += colorused[i-1];
1628   }
1629   ncolors = colorused[5*ncolors-1];
1630   for (i=0; i<n; i++) {
1631     newcolor[i] = colorused[newcolor[i]]-1;
1632   }
1633   ierr = PetscFree(colorused);CHKERRQ(ierr);
1634   ierr = ISColoringCreate(((PetscObject)mat)->comm,ncolors,n,newcolor,iscoloring);CHKERRQ(ierr);
1635   ierr = PetscFree(coloring);CHKERRQ(ierr);
1636   PetscFunctionReturn(0);
1637 }
1638 
1639 #include "src/inline/ilu.h"
1640 
1641 #undef __FUNCT__
1642 #define __FUNCT__ "MatRelax_Inode"
1643 PetscErrorCode MatRelax_Inode(Mat A,Vec bb,PetscReal omega,MatSORType flag,PetscReal fshift,PetscInt its,PetscInt lits,Vec xx)
1644 {
1645   Mat_SeqAIJ         *a = (Mat_SeqAIJ*)A->data;
1646   PetscScalar        *x,*xs,sum1,sum2,sum3,sum4,sum5,tmp0,tmp1,tmp2,tmp3;
1647   MatScalar          *ibdiag,*bdiag;
1648   PetscScalar        *b,*xb,tmp4,tmp5,x1,x2,x3,x4,x5;
1649   const MatScalar    *v = a->a,*v1,*v2,*v3,*v4,*v5;
1650   PetscReal          zeropivot = 1.0e-15, shift = 0.0;
1651   PetscErrorCode     ierr;
1652   PetscInt           n,m = a->inode.node_count,*sizes = a->inode.size,cnt = 0,i,j,row,i1,i2;
1653   PetscInt           *idx,*diag = a->diag,*ii = a->i,sz,k;
1654 
1655   PetscFunctionBegin;
1656   if (omega != 1.0) SETERRQ(PETSC_ERR_SUP,"No support for omega != 1.0; use -mat_no_inode");
1657   if (fshift != 0.0) SETERRQ(PETSC_ERR_SUP,"No support for fshift != 0.0; use -mat_no_inode");
1658   if (flag & SOR_EISENSTAT) SETERRQ(PETSC_ERR_SUP,"No support for Eisenstat trick; use -mat_no_inode");
1659 
1660   if (!a->inode.ibdiagvalid) {
1661     if (!a->inode.ibdiag) {
1662       /* calculate space needed for diagonal blocks */
1663       for (i=0; i<m; i++) {
1664 	cnt += sizes[i]*sizes[i];
1665       }
1666       a->inode.bdiagsize = cnt;
1667       ierr   = PetscMalloc2(cnt,MatScalar,&a->inode.ibdiag,cnt,MatScalar,&a->inode.bdiag);CHKERRQ(ierr);
1668     }
1669 
1670     /* copy over the diagonal blocks and invert them */
1671     ibdiag = a->inode.ibdiag;
1672     bdiag  = a->inode.bdiag;
1673     cnt = 0;
1674     for (i=0, row = 0; i<m; i++) {
1675       for (j=0; j<sizes[i]; j++) {
1676         for (k=0; k<sizes[i]; k++) {
1677           bdiag[cnt+k*sizes[i]+j] = v[diag[row+j] - j + k];
1678         }
1679       }
1680       ierr = PetscMemcpy(ibdiag+cnt,bdiag+cnt,sizes[i]*sizes[i]*sizeof(MatScalar));CHKERRQ(ierr);
1681 
1682       switch(sizes[i]) {
1683         case 1:
1684           /* Create matrix data structure */
1685           if (PetscAbsScalar(ibdiag[cnt]) < zeropivot) SETERRQ1(PETSC_ERR_MAT_LU_ZRPVT,"Zero pivot on row %D",row);
1686           ibdiag[cnt] = 1.0/ibdiag[cnt];
1687           break;
1688         case 2:
1689           ierr = Kernel_A_gets_inverse_A_2(ibdiag+cnt,shift);CHKERRQ(ierr);
1690           break;
1691         case 3:
1692           ierr = Kernel_A_gets_inverse_A_3(ibdiag+cnt,shift);CHKERRQ(ierr);
1693           break;
1694         case 4:
1695           ierr = Kernel_A_gets_inverse_A_4(ibdiag+cnt,shift);CHKERRQ(ierr);
1696           break;
1697         case 5:
1698           ierr = Kernel_A_gets_inverse_A_5(ibdiag+cnt,shift);CHKERRQ(ierr);
1699           break;
1700        default:
1701 	 SETERRQ1(PETSC_ERR_SUP,"Inode size %D not supported",sizes[i]);
1702       }
1703       cnt += sizes[i]*sizes[i];
1704       row += sizes[i];
1705     }
1706     a->inode.ibdiagvalid = PETSC_TRUE;
1707   }
1708   ibdiag = a->inode.ibdiag;
1709   bdiag  = a->inode.bdiag;
1710 
1711   ierr = VecGetArray(xx,&x);CHKERRQ(ierr);
1712   if (xx != bb) {
1713     ierr = VecGetArray(bb,(PetscScalar**)&b);CHKERRQ(ierr);
1714   } else {
1715     b = x;
1716   }
1717 
1718   /* We count flops by assuming the upper triangular and lower triangular parts have the same number of nonzeros */
1719   xs   = x;
1720   if (flag & SOR_ZERO_INITIAL_GUESS) {
1721     if (flag & SOR_FORWARD_SWEEP || flag & SOR_LOCAL_FORWARD_SWEEP){
1722 
1723       for (i=0, row=0; i<m; i++) {
1724         sz  = diag[row] - ii[row];
1725         v1  = a->a + ii[row];
1726         idx = a->j + ii[row];
1727 
1728         /* see comments for MatMult_Inode() for how this is coded */
1729         switch (sizes[i]){
1730           case 1:
1731 
1732             sum1  = b[row];
1733             for(n = 0; n<sz-1; n+=2) {
1734               i1   = idx[0];
1735               i2   = idx[1];
1736               idx += 2;
1737               tmp0 = x[i1];
1738               tmp1 = x[i2];
1739               sum1 -= v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
1740             }
1741 
1742             if (n == sz-1){
1743               tmp0  = x[*idx];
1744               sum1 -= *v1 * tmp0;
1745             }
1746             x[row++] = sum1*(*ibdiag++);
1747             break;
1748           case 2:
1749             v2    = a->a + ii[row+1];
1750             sum1  = b[row];
1751             sum2  = b[row+1];
1752             for(n = 0; n<sz-1; n+=2) {
1753               i1   = idx[0];
1754               i2   = idx[1];
1755               idx += 2;
1756               tmp0 = x[i1];
1757               tmp1 = x[i2];
1758               sum1 -= v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
1759               sum2 -= v2[0] * tmp0 + v2[1] * tmp1; v2 += 2;
1760             }
1761 
1762             if (n == sz-1){
1763               tmp0  = x[*idx];
1764               sum1 -= v1[0] * tmp0;
1765               sum2 -= v2[0] * tmp0;
1766             }
1767             x[row++] = sum1*ibdiag[0] + sum2*ibdiag[2];
1768             x[row++] = sum1*ibdiag[1] + sum2*ibdiag[3];
1769             ibdiag  += 4;
1770             break;
1771           case 3:
1772             v2    = a->a + ii[row+1];
1773             v3    = a->a + ii[row+2];
1774             sum1  = b[row];
1775             sum2  = b[row+1];
1776             sum3  = b[row+2];
1777             for(n = 0; n<sz-1; n+=2) {
1778               i1   = idx[0];
1779               i2   = idx[1];
1780               idx += 2;
1781               tmp0 = x[i1];
1782               tmp1 = x[i2];
1783               sum1 -= v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
1784               sum2 -= v2[0] * tmp0 + v2[1] * tmp1; v2 += 2;
1785               sum3 -= v3[0] * tmp0 + v3[1] * tmp1; v3 += 2;
1786             }
1787 
1788             if (n == sz-1){
1789               tmp0  = x[*idx];
1790               sum1 -= v1[0] * tmp0;
1791               sum2 -= v2[0] * tmp0;
1792               sum3 -= v3[0] * tmp0;
1793             }
1794             x[row++] = sum1*ibdiag[0] + sum2*ibdiag[3] + sum3*ibdiag[6];
1795             x[row++] = sum1*ibdiag[1] + sum2*ibdiag[4] + sum3*ibdiag[7];
1796             x[row++] = sum1*ibdiag[2] + sum2*ibdiag[5] + sum3*ibdiag[8];
1797             ibdiag  += 9;
1798             break;
1799           case 4:
1800             v2    = a->a + ii[row+1];
1801             v3    = a->a + ii[row+2];
1802             v4    = a->a + ii[row+3];
1803             sum1  = b[row];
1804             sum2  = b[row+1];
1805             sum3  = b[row+2];
1806             sum4  = b[row+3];
1807             for(n = 0; n<sz-1; n+=2) {
1808               i1   = idx[0];
1809               i2   = idx[1];
1810               idx += 2;
1811               tmp0 = x[i1];
1812               tmp1 = x[i2];
1813               sum1 -= v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
1814               sum2 -= v2[0] * tmp0 + v2[1] * tmp1; v2 += 2;
1815               sum3 -= v3[0] * tmp0 + v3[1] * tmp1; v3 += 2;
1816               sum4 -= v4[0] * tmp0 + v4[1] * tmp1; v4 += 2;
1817             }
1818 
1819             if (n == sz-1){
1820               tmp0  = x[*idx];
1821               sum1 -= v1[0] * tmp0;
1822               sum2 -= v2[0] * tmp0;
1823               sum3 -= v3[0] * tmp0;
1824               sum4 -= v4[0] * tmp0;
1825             }
1826             x[row++] = sum1*ibdiag[0] + sum2*ibdiag[4] + sum3*ibdiag[8] + sum4*ibdiag[12];
1827             x[row++] = sum1*ibdiag[1] + sum2*ibdiag[5] + sum3*ibdiag[9] + sum4*ibdiag[13];
1828             x[row++] = sum1*ibdiag[2] + sum2*ibdiag[6] + sum3*ibdiag[10] + sum4*ibdiag[14];
1829             x[row++] = sum1*ibdiag[3] + sum2*ibdiag[7] + sum3*ibdiag[11] + sum4*ibdiag[15];
1830             ibdiag  += 16;
1831             break;
1832           case 5:
1833             v2    = a->a + ii[row+1];
1834             v3    = a->a + ii[row+2];
1835             v4    = a->a + ii[row+3];
1836             v5    = a->a + ii[row+4];
1837             sum1  = b[row];
1838             sum2  = b[row+1];
1839             sum3  = b[row+2];
1840             sum4  = b[row+3];
1841             sum5  = b[row+4];
1842             for(n = 0; n<sz-1; n+=2) {
1843               i1   = idx[0];
1844               i2   = idx[1];
1845               idx += 2;
1846               tmp0 = x[i1];
1847               tmp1 = x[i2];
1848               sum1 -= v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
1849               sum2 -= v2[0] * tmp0 + v2[1] * tmp1; v2 += 2;
1850               sum3 -= v3[0] * tmp0 + v3[1] * tmp1; v3 += 2;
1851               sum4 -= v4[0] * tmp0 + v4[1] * tmp1; v4 += 2;
1852               sum5 -= v5[0] * tmp0 + v5[1] * tmp1; v5 += 2;
1853             }
1854 
1855             if (n == sz-1){
1856               tmp0  = x[*idx];
1857               sum1 -= v1[0] * tmp0;
1858               sum2 -= v2[0] * tmp0;
1859               sum3 -= v3[0] * tmp0;
1860               sum4 -= v4[0] * tmp0;
1861               sum5 -= v5[0] * tmp0;
1862             }
1863             x[row++] = sum1*ibdiag[0] + sum2*ibdiag[5] + sum3*ibdiag[10] + sum4*ibdiag[15] + sum5*ibdiag[20];
1864             x[row++] = sum1*ibdiag[1] + sum2*ibdiag[6] + sum3*ibdiag[11] + sum4*ibdiag[16] + sum5*ibdiag[21];
1865             x[row++] = sum1*ibdiag[2] + sum2*ibdiag[7] + sum3*ibdiag[12] + sum4*ibdiag[17] + sum5*ibdiag[22];
1866             x[row++] = sum1*ibdiag[3] + sum2*ibdiag[8] + sum3*ibdiag[13] + sum4*ibdiag[18] + sum5*ibdiag[23];
1867             x[row++] = sum1*ibdiag[4] + sum2*ibdiag[9] + sum3*ibdiag[14] + sum4*ibdiag[19] + sum5*ibdiag[24];
1868             ibdiag  += 25;
1869             break;
1870 	  default:
1871    	    SETERRQ1(PETSC_ERR_SUP,"Inode size %D not supported",sizes[i]);
1872         }
1873       }
1874 
1875       xb = x;
1876       ierr = PetscLogFlops(a->nz);CHKERRQ(ierr);
1877     } else xb = b;
1878     if ((flag & SOR_FORWARD_SWEEP || flag & SOR_LOCAL_FORWARD_SWEEP) &&
1879         (flag & SOR_BACKWARD_SWEEP || flag & SOR_LOCAL_BACKWARD_SWEEP)) {
1880       cnt = 0;
1881       for (i=0, row=0; i<m; i++) {
1882 
1883         switch (sizes[i]){
1884           case 1:
1885             x[row++] *= bdiag[cnt++];
1886             break;
1887           case 2:
1888             x1   = x[row]; x2 = x[row+1];
1889             tmp1 = x1*bdiag[cnt] + x2*bdiag[cnt+2];
1890             tmp2 = x1*bdiag[cnt+1] + x2*bdiag[cnt+3];
1891             x[row++] = tmp1;
1892             x[row++] = tmp2;
1893             cnt += 4;
1894             break;
1895           case 3:
1896             x1   = x[row]; x2 = x[row+1]; x3 = x[row+2];
1897             tmp1 = x1*bdiag[cnt] + x2*bdiag[cnt+3] + x3*bdiag[cnt+6];
1898             tmp2 = x1*bdiag[cnt+1] + x2*bdiag[cnt+4] + x3*bdiag[cnt+7];
1899             tmp3 = x1*bdiag[cnt+2] + x2*bdiag[cnt+5] + x3*bdiag[cnt+8];
1900             x[row++] = tmp1;
1901             x[row++] = tmp2;
1902             x[row++] = tmp3;
1903             cnt += 9;
1904             break;
1905           case 4:
1906             x1   = x[row]; x2 = x[row+1]; x3 = x[row+2]; x4 = x[row+3];
1907             tmp1 = x1*bdiag[cnt] + x2*bdiag[cnt+4] + x3*bdiag[cnt+8] + x4*bdiag[cnt+12];
1908             tmp2 = x1*bdiag[cnt+1] + x2*bdiag[cnt+5] + x3*bdiag[cnt+9] + x4*bdiag[cnt+13];
1909             tmp3 = x1*bdiag[cnt+2] + x2*bdiag[cnt+6] + x3*bdiag[cnt+10] + x4*bdiag[cnt+14];
1910             tmp4 = x1*bdiag[cnt+3] + x2*bdiag[cnt+7] + x3*bdiag[cnt+11] + x4*bdiag[cnt+15];
1911             x[row++] = tmp1;
1912             x[row++] = tmp2;
1913             x[row++] = tmp3;
1914             x[row++] = tmp4;
1915             cnt += 16;
1916             break;
1917           case 5:
1918             x1   = x[row]; x2 = x[row+1]; x3 = x[row+2]; x4 = x[row+3]; x5 = x[row+4];
1919             tmp1 = x1*bdiag[cnt] + x2*bdiag[cnt+5] + x3*bdiag[cnt+10] + x4*bdiag[cnt+15] + x5*bdiag[cnt+20];
1920             tmp2 = x1*bdiag[cnt+1] + x2*bdiag[cnt+6] + x3*bdiag[cnt+11] + x4*bdiag[cnt+16] + x5*bdiag[cnt+21];
1921             tmp3 = x1*bdiag[cnt+2] + x2*bdiag[cnt+7] + x3*bdiag[cnt+12] + x4*bdiag[cnt+17] + x5*bdiag[cnt+22];
1922             tmp4 = x1*bdiag[cnt+3] + x2*bdiag[cnt+8] + x3*bdiag[cnt+13] + x4*bdiag[cnt+18] + x5*bdiag[cnt+23];
1923             tmp5 = x1*bdiag[cnt+4] + x2*bdiag[cnt+9] + x3*bdiag[cnt+14] + x4*bdiag[cnt+19] + x5*bdiag[cnt+24];
1924             x[row++] = tmp1;
1925             x[row++] = tmp2;
1926             x[row++] = tmp3;
1927             x[row++] = tmp4;
1928             x[row++] = tmp5;
1929             cnt += 25;
1930             break;
1931 	  default:
1932    	    SETERRQ1(PETSC_ERR_SUP,"Inode size %D not supported",sizes[i]);
1933         }
1934       }
1935       ierr = PetscLogFlops(m);CHKERRQ(ierr);
1936     }
1937     if (flag & SOR_BACKWARD_SWEEP || flag & SOR_LOCAL_BACKWARD_SWEEP){
1938 
1939       ibdiag = a->inode.ibdiag+a->inode.bdiagsize;
1940       for (i=m-1, row=A->rmap.n-1; i>=0; i--) {
1941         ibdiag -= sizes[i]*sizes[i];
1942         sz      = ii[row+1] - diag[row] - 1;
1943         v1      = a->a + diag[row] + 1;
1944         idx     = a->j + diag[row] + 1;
1945 
1946         /* see comments for MatMult_Inode() for how this is coded */
1947         switch (sizes[i]){
1948           case 1:
1949 
1950             sum1  = xb[row];
1951             for(n = 0; n<sz-1; n+=2) {
1952               i1   = idx[0];
1953               i2   = idx[1];
1954               idx += 2;
1955               tmp0 = x[i1];
1956               tmp1 = x[i2];
1957               sum1 -= v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
1958             }
1959 
1960             if (n == sz-1){
1961               tmp0  = x[*idx];
1962               sum1 -= *v1*tmp0;
1963             }
1964             x[row--] = sum1*(*ibdiag);
1965             break;
1966 
1967           case 2:
1968 
1969             sum1  = xb[row];
1970             sum2  = xb[row-1];
1971             /* note that sum1 is associated with the second of the two rows */
1972             v2    = a->a + diag[row-1] + 2;
1973             for(n = 0; n<sz-1; n+=2) {
1974               i1   = idx[0];
1975               i2   = idx[1];
1976               idx += 2;
1977               tmp0 = x[i1];
1978               tmp1 = x[i2];
1979               sum1 -= v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
1980               sum2 -= v2[0] * tmp0 + v2[1] * tmp1; v2 += 2;
1981             }
1982 
1983             if (n == sz-1){
1984               tmp0  = x[*idx];
1985               sum1 -= *v1*tmp0;
1986               sum2 -= *v2*tmp0;
1987             }
1988             x[row--] = sum2*ibdiag[1] + sum1*ibdiag[3];
1989             x[row--] = sum2*ibdiag[0] + sum1*ibdiag[2];
1990             break;
1991           case 3:
1992 
1993             sum1  = xb[row];
1994             sum2  = xb[row-1];
1995             sum3  = xb[row-2];
1996             v2    = a->a + diag[row-1] + 2;
1997             v3    = a->a + diag[row-2] + 3;
1998             for(n = 0; n<sz-1; n+=2) {
1999               i1   = idx[0];
2000               i2   = idx[1];
2001               idx += 2;
2002               tmp0 = x[i1];
2003               tmp1 = x[i2];
2004               sum1 -= v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
2005               sum2 -= v2[0] * tmp0 + v2[1] * tmp1; v2 += 2;
2006               sum3 -= v3[0] * tmp0 + v3[1] * tmp1; v3 += 2;
2007             }
2008 
2009             if (n == sz-1){
2010               tmp0  = x[*idx];
2011               sum1 -= *v1*tmp0;
2012               sum2 -= *v2*tmp0;
2013               sum3 -= *v3*tmp0;
2014             }
2015             x[row--] = sum3*ibdiag[2] + sum2*ibdiag[5] + sum1*ibdiag[8];
2016             x[row--] = sum3*ibdiag[1] + sum2*ibdiag[4] + sum1*ibdiag[7];
2017             x[row--] = sum3*ibdiag[0] + sum2*ibdiag[3] + sum1*ibdiag[6];
2018             break;
2019           case 4:
2020 
2021             sum1  = xb[row];
2022             sum2  = xb[row-1];
2023             sum3  = xb[row-2];
2024             sum4  = xb[row-3];
2025             v2    = a->a + diag[row-1] + 2;
2026             v3    = a->a + diag[row-2] + 3;
2027             v4    = a->a + diag[row-3] + 4;
2028             for(n = 0; n<sz-1; n+=2) {
2029               i1   = idx[0];
2030               i2   = idx[1];
2031               idx += 2;
2032               tmp0 = x[i1];
2033               tmp1 = x[i2];
2034               sum1 -= v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
2035               sum2 -= v2[0] * tmp0 + v2[1] * tmp1; v2 += 2;
2036               sum3 -= v3[0] * tmp0 + v3[1] * tmp1; v3 += 2;
2037               sum4 -= v4[0] * tmp0 + v4[1] * tmp1; v4 += 2;
2038             }
2039 
2040             if (n == sz-1){
2041               tmp0  = x[*idx];
2042               sum1 -= *v1*tmp0;
2043               sum2 -= *v2*tmp0;
2044               sum3 -= *v3*tmp0;
2045               sum4 -= *v4*tmp0;
2046             }
2047             x[row--] = sum4*ibdiag[3] + sum3*ibdiag[7] + sum2*ibdiag[11] + sum1*ibdiag[15];
2048             x[row--] = sum4*ibdiag[2] + sum3*ibdiag[6] + sum2*ibdiag[10] + sum1*ibdiag[14];
2049             x[row--] = sum4*ibdiag[1] + sum3*ibdiag[5] + sum2*ibdiag[9] + sum1*ibdiag[13];
2050             x[row--] = sum4*ibdiag[0] + sum3*ibdiag[4] + sum2*ibdiag[8] + sum1*ibdiag[12];
2051             break;
2052           case 5:
2053 
2054             sum1  = xb[row];
2055             sum2  = xb[row-1];
2056             sum3  = xb[row-2];
2057             sum4  = xb[row-3];
2058             sum5  = xb[row-4];
2059             v2    = a->a + diag[row-1] + 2;
2060             v3    = a->a + diag[row-2] + 3;
2061             v4    = a->a + diag[row-3] + 4;
2062             v5    = a->a + diag[row-4] + 5;
2063             for(n = 0; n<sz-1; n+=2) {
2064               i1   = idx[0];
2065               i2   = idx[1];
2066               idx += 2;
2067               tmp0 = x[i1];
2068               tmp1 = x[i2];
2069               sum1 -= v1[0] * tmp0 + v1[1] * tmp1; v1 += 2;
2070               sum2 -= v2[0] * tmp0 + v2[1] * tmp1; v2 += 2;
2071               sum3 -= v3[0] * tmp0 + v3[1] * tmp1; v3 += 2;
2072               sum4 -= v4[0] * tmp0 + v4[1] * tmp1; v4 += 2;
2073               sum5 -= v5[0] * tmp0 + v5[1] * tmp1; v5 += 2;
2074             }
2075 
2076             if (n == sz-1){
2077               tmp0  = x[*idx];
2078               sum1 -= *v1*tmp0;
2079               sum2 -= *v2*tmp0;
2080               sum3 -= *v3*tmp0;
2081               sum4 -= *v4*tmp0;
2082               sum5 -= *v5*tmp0;
2083             }
2084             x[row--] = sum5*ibdiag[4] + sum4*ibdiag[9] + sum3*ibdiag[14] + sum2*ibdiag[19] + sum1*ibdiag[24];
2085             x[row--] = sum5*ibdiag[3] + sum4*ibdiag[8] + sum3*ibdiag[13] + sum2*ibdiag[18] + sum1*ibdiag[23];
2086             x[row--] = sum5*ibdiag[2] + sum4*ibdiag[7] + sum3*ibdiag[12] + sum2*ibdiag[17] + sum1*ibdiag[22];
2087             x[row--] = sum5*ibdiag[1] + sum4*ibdiag[6] + sum3*ibdiag[11] + sum2*ibdiag[16] + sum1*ibdiag[21];
2088             x[row--] = sum5*ibdiag[0] + sum4*ibdiag[5] + sum3*ibdiag[10] + sum2*ibdiag[15] + sum1*ibdiag[20];
2089             break;
2090 	  default:
2091    	    SETERRQ1(PETSC_ERR_SUP,"Inode size %D not supported",sizes[i]);
2092         }
2093       }
2094 
2095       ierr = PetscLogFlops(a->nz);CHKERRQ(ierr);
2096     }
2097     its--;
2098   }
2099   if (its) SETERRQ(PETSC_ERR_SUP,"Currently no support for multiply SOR sweeps using inode version of AIJ matrix format;\n run with the option -mat_no_inode");
2100   ierr = VecRestoreArray(xx,&x);CHKERRQ(ierr);
2101   if (bb != xx) {ierr = VecRestoreArray(bb,(PetscScalar**)&b);CHKERRQ(ierr);}
2102   PetscFunctionReturn(0);
2103 }
2104 
2105 
2106 /*
2107     samestructure indicates that the matrix has not changed its nonzero structure so we
2108     do not need to recompute the inodes
2109 */
2110 #undef __FUNCT__
2111 #define __FUNCT__ "Mat_CheckInode"
2112 PetscErrorCode Mat_CheckInode(Mat A,PetscTruth samestructure)
2113 {
2114   Mat_SeqAIJ     *a = (Mat_SeqAIJ*)A->data;
2115   PetscErrorCode ierr;
2116   PetscInt       i,j,m,nzx,nzy,*idx,*idy,*ns,*ii,node_count,blk_size;
2117   PetscTruth     flag;
2118 
2119   PetscFunctionBegin;
2120   if (!a->inode.use)                     PetscFunctionReturn(0);
2121   if (a->inode.checked && samestructure) PetscFunctionReturn(0);
2122 
2123 
2124   m = A->rmap.n;
2125   if (a->inode.size) {ns = a->inode.size;}
2126   else {ierr = PetscMalloc((m+1)*sizeof(PetscInt),&ns);CHKERRQ(ierr);}
2127 
2128   i          = 0;
2129   node_count = 0;
2130   idx        = a->j;
2131   ii         = a->i;
2132   while (i < m){                /* For each row */
2133     nzx = ii[i+1] - ii[i];       /* Number of nonzeros */
2134     /* Limits the number of elements in a node to 'a->inode.limit' */
2135     for (j=i+1,idy=idx,blk_size=1; j<m && blk_size <a->inode.limit; ++j,++blk_size) {
2136       nzy     = ii[j+1] - ii[j]; /* Same number of nonzeros */
2137       if (nzy != nzx) break;
2138       idy  += nzx;             /* Same nonzero pattern */
2139       ierr = PetscMemcmp(idx,idy,nzx*sizeof(PetscInt),&flag);CHKERRQ(ierr);
2140       if (!flag) break;
2141     }
2142     ns[node_count++] = blk_size;
2143     idx += blk_size*nzx;
2144     i    = j;
2145   }
2146   /* If not enough inodes found,, do not use inode version of the routines */
2147   if (!a->inode.size && m && node_count > .9*m) {
2148     ierr = PetscFree(ns);CHKERRQ(ierr);
2149     a->inode.node_count     = 0;
2150     a->inode.size           = PETSC_NULL;
2151     a->inode.use            = PETSC_FALSE;
2152     ierr = PetscInfo2(A,"Found %D nodes out of %D rows. Not using Inode routines\n",node_count,m);CHKERRQ(ierr);
2153   } else {
2154     A->ops->mult            = MatMult_Inode;
2155     A->ops->relax           = MatRelax_Inode;
2156     A->ops->multadd         = MatMultAdd_Inode;
2157     A->ops->solve           = MatSolve_Inode;
2158     A->ops->lufactornumeric = MatLUFactorNumeric_Inode;
2159     A->ops->getrowij        = MatGetRowIJ_Inode;
2160     A->ops->restorerowij    = MatRestoreRowIJ_Inode;
2161     A->ops->getcolumnij     = MatGetColumnIJ_Inode;
2162     A->ops->restorecolumnij = MatRestoreColumnIJ_Inode;
2163     A->ops->coloringpatch   = MatColoringPatch_Inode;
2164     a->inode.node_count     = node_count;
2165     a->inode.size           = ns;
2166     ierr = PetscInfo3(A,"Found %D nodes of %D. Limit used: %D. Using Inode routines\n",node_count,m,a->inode.limit);CHKERRQ(ierr);
2167   }
2168   PetscFunctionReturn(0);
2169 }
2170 
2171 /*
2172      This is really ugly. if inodes are used this replaces the
2173   permutations with ones that correspond to rows/cols of the matrix
2174   rather then inode blocks
2175 */
2176 #undef __FUNCT__
2177 #define __FUNCT__ "MatInodeAdjustForInodes"
2178 PetscErrorCode PETSCMAT_DLLEXPORT MatInodeAdjustForInodes(Mat A,IS *rperm,IS *cperm)
2179 {
2180   PetscErrorCode ierr,(*f)(Mat,IS*,IS*);
2181 
2182   PetscFunctionBegin;
2183   ierr = PetscObjectQueryFunction((PetscObject)A,"MatInodeAdjustForInodes_C",(void (**)(void))&f);CHKERRQ(ierr);
2184   if (f) {
2185     ierr = (*f)(A,rperm,cperm);CHKERRQ(ierr);
2186   }
2187   PetscFunctionReturn(0);
2188 }
2189 
2190 EXTERN_C_BEGIN
2191 #undef __FUNCT__
2192 #define __FUNCT__ "MatAdjustForInodes_Inode"
2193 PetscErrorCode PETSCMAT_DLLEXPORT MatInodeAdjustForInodes_Inode(Mat A,IS *rperm,IS *cperm)
2194 {
2195   Mat_SeqAIJ      *a=(Mat_SeqAIJ*)A->data;
2196   PetscErrorCode ierr;
2197   PetscInt       m = A->rmap.n,n = A->cmap.n,i,j,*ridx,*cidx,nslim_row = a->inode.node_count;
2198   PetscInt       row,col,*permr,*permc,*ns_row =  a->inode.size,*tns,start_val,end_val,indx;
2199   PetscInt       nslim_col,*ns_col;
2200   IS             ris = *rperm,cis = *cperm;
2201 
2202   PetscFunctionBegin;
2203   if (!a->inode.size) PetscFunctionReturn(0); /* no inodes so return */
2204   if (a->inode.node_count == m) PetscFunctionReturn(0); /* all inodes are of size 1 */
2205 
2206   ierr  = Mat_CreateColInode(A,&nslim_col,&ns_col);CHKERRQ(ierr);
2207   ierr  = PetscMalloc((((nslim_row>nslim_col)?nslim_row:nslim_col)+1)*sizeof(PetscInt),&tns);CHKERRQ(ierr);
2208   ierr  = PetscMalloc((m+n+1)*sizeof(PetscInt),&permr);CHKERRQ(ierr);
2209   permc = permr + m;
2210 
2211   ierr  = ISGetIndices(ris,&ridx);CHKERRQ(ierr);
2212   ierr  = ISGetIndices(cis,&cidx);CHKERRQ(ierr);
2213 
2214   /* Form the inode structure for the rows of permuted matric using inv perm*/
2215   for (i=0,tns[0]=0; i<nslim_row; ++i) tns[i+1] = tns[i] + ns_row[i];
2216 
2217   /* Construct the permutations for rows*/
2218   for (i=0,row = 0; i<nslim_row; ++i){
2219     indx      = ridx[i];
2220     start_val = tns[indx];
2221     end_val   = tns[indx + 1];
2222     for (j=start_val; j<end_val; ++j,++row) permr[row]= j;
2223   }
2224 
2225   /* Form the inode structure for the columns of permuted matrix using inv perm*/
2226   for (i=0,tns[0]=0; i<nslim_col; ++i) tns[i+1] = tns[i] + ns_col[i];
2227 
2228  /* Construct permutations for columns */
2229   for (i=0,col=0; i<nslim_col; ++i){
2230     indx      = cidx[i];
2231     start_val = tns[indx];
2232     end_val   = tns[indx + 1];
2233     for (j = start_val; j<end_val; ++j,++col) permc[col]= j;
2234   }
2235 
2236   ierr = ISCreateGeneral(PETSC_COMM_SELF,n,permr,rperm);CHKERRQ(ierr);
2237   ISSetPermutation(*rperm);
2238   ierr = ISCreateGeneral(PETSC_COMM_SELF,n,permc,cperm);CHKERRQ(ierr);
2239   ISSetPermutation(*cperm);
2240 
2241   ierr  = ISRestoreIndices(ris,&ridx);CHKERRQ(ierr);
2242   ierr  = ISRestoreIndices(cis,&cidx);CHKERRQ(ierr);
2243 
2244   ierr = PetscFree(ns_col);CHKERRQ(ierr);
2245   ierr = PetscFree(permr);CHKERRQ(ierr);
2246   ierr = ISDestroy(cis);CHKERRQ(ierr);
2247   ierr = ISDestroy(ris);CHKERRQ(ierr);
2248   ierr = PetscFree(tns);CHKERRQ(ierr);
2249   PetscFunctionReturn(0);
2250 }
2251 EXTERN_C_END
2252 
2253 #undef __FUNCT__
2254 #define __FUNCT__ "MatInodeGetInodeSizes"
2255 /*@C
2256    MatInodeGetInodeSizes - Returns the inode information of the Inode matrix.
2257 
2258    Collective on Mat
2259 
2260    Input Parameter:
2261 .  A - the Inode matrix or matrix derived from the Inode class -- e.g., SeqAIJ
2262 
2263    Output Parameter:
2264 +  node_count - no of inodes present in the matrix.
2265 .  sizes      - an array of size node_count,with sizes of each inode.
2266 -  limit      - the max size used to generate the inodes.
2267 
2268    Level: advanced
2269 
2270    Notes: This routine returns some internal storage information
2271    of the matrix, it is intended to be used by advanced users.
2272    It should be called after the matrix is assembled.
2273    The contents of the sizes[] array should not be changed.
2274    PETSC_NULL may be passed for information not requested.
2275 
2276 .keywords: matrix, seqaij, get, inode
2277 
2278 .seealso: MatGetInfo()
2279 @*/
2280 PetscErrorCode PETSCMAT_DLLEXPORT MatInodeGetInodeSizes(Mat A,PetscInt *node_count,PetscInt *sizes[],PetscInt *limit)
2281 {
2282   PetscErrorCode ierr,(*f)(Mat,PetscInt*,PetscInt*[],PetscInt*);
2283 
2284   PetscFunctionBegin;
2285   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2286   ierr = PetscObjectQueryFunction((PetscObject)A,"MatInodeGetInodeSizes_C",(void (**)(void))&f);CHKERRQ(ierr);
2287   if (f) {
2288     ierr = (*f)(A,node_count,sizes,limit);CHKERRQ(ierr);
2289   }
2290   PetscFunctionReturn(0);
2291 }
2292 
2293 EXTERN_C_BEGIN
2294 #undef __FUNCT__
2295 #define __FUNCT__ "MatInodeGetInodeSizes_Inode"
2296 PetscErrorCode PETSCMAT_DLLEXPORT MatInodeGetInodeSizes_Inode(Mat A,PetscInt *node_count,PetscInt *sizes[],PetscInt *limit)
2297 {
2298   Mat_SeqAIJ *a = (Mat_SeqAIJ*)A->data;
2299 
2300   PetscFunctionBegin;
2301   if (node_count) *node_count = a->inode.node_count;
2302   if (sizes)      *sizes      = a->inode.size;
2303   if (limit)      *limit      = a->inode.limit;
2304   PetscFunctionReturn(0);
2305 }
2306 EXTERN_C_END
2307