xref: /petsc/src/mat/impls/baij/seq/baijfact7.c (revision 6abefa4f446b2ea91915da4e25ea0defa83db48e)
1 #define PETSCMAT_DLL
2 
3 /*
4     Factorization code for BAIJ format.
5 */
6 #include "../src/mat/impls/baij/seq/baij.h"
7 #include "../src/mat/blockinvert.h"
8 
9 /* ------------------------------------------------------------*/
10 /*
11       Version for when blocks are 6 by 6
12 */
13 #undef __FUNCT__
14 #define __FUNCT__ "MatLUFactorNumeric_SeqBAIJ_6_inplace"
15 PetscErrorCode MatLUFactorNumeric_SeqBAIJ_6_inplace(Mat C,Mat A,const MatFactorInfo *info)
16 {
17   Mat_SeqBAIJ    *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
18   IS             isrow = b->row,isicol = b->icol;
19   PetscErrorCode ierr;
20   const PetscInt *ajtmpold,*ajtmp,*diag_offset = b->diag,*r,*ic,*bi = b->i,*bj = b->j,*ai=a->i,*aj=a->j,*pj;
21   PetscInt       nz,row,i,j,n = a->mbs,idx;
22   MatScalar      *pv,*v,*rtmp,*pc,*w,*x;
23   MatScalar      p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
24   MatScalar      p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
25   MatScalar      x17,x18,x19,x20,x21,x22,x23,x24,x25,p10,p11,p12,p13,p14;
26   MatScalar      p15,p16,p17,p18,p19,p20,p21,p22,p23,p24,p25,m10,m11,m12;
27   MatScalar      m13,m14,m15,m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
28   MatScalar      p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
29   MatScalar      x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
30   MatScalar      m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
31   MatScalar      *ba = b->a,*aa = a->a;
32   PetscReal      shift = info->shiftamount;
33 
34   PetscFunctionBegin;
35   ierr = ISGetIndices(isrow,&r);CHKERRQ(ierr);
36   ierr = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
37   ierr = PetscMalloc(36*(n+1)*sizeof(MatScalar),&rtmp);CHKERRQ(ierr);
38 
39   for (i=0; i<n; i++) {
40     nz    = bi[i+1] - bi[i];
41     ajtmp = bj + bi[i];
42     for  (j=0; j<nz; j++) {
43       x = rtmp+36*ajtmp[j];
44       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
45       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
46       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
47       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
48       x[34] = x[35] = 0.0 ;
49     }
50     /* load in initial (unfactored row) */
51     idx      = r[i];
52     nz       = ai[idx+1] - ai[idx];
53     ajtmpold = aj + ai[idx];
54     v        = aa + 36*ai[idx];
55     for (j=0; j<nz; j++) {
56       x    = rtmp+36*ic[ajtmpold[j]];
57       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
58       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
59       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
60       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
61       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
62       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
63       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
64       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
65       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
66       v    += 36;
67     }
68     row = *ajtmp++;
69     while (row < i) {
70       pc  =  rtmp + 36*row;
71       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
72       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
73       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
74       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
75       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
76       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
77       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
78       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
79       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
80       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
81           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
82           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
83           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
84           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
85           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
86           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
87           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
88           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0) {
89         pv = ba + 36*diag_offset[row];
90         pj = bj + diag_offset[row] + 1;
91 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
92 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
93 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
94 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
95 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
96 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
97 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
98 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
99 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
100         pc[0]  = m1  = p1*x1  + p7*x2   + p13*x3  + p19*x4  + p25*x5  + p31*x6;
101         pc[1]  = m2  = p2*x1  + p8*x2   + p14*x3  + p20*x4  + p26*x5  + p32*x6;
102         pc[2]  = m3  = p3*x1  + p9*x2   + p15*x3  + p21*x4  + p27*x5  + p33*x6;
103         pc[3]  = m4  = p4*x1  + p10*x2  + p16*x3  + p22*x4  + p28*x5  + p34*x6;
104         pc[4]  = m5  = p5*x1  + p11*x2  + p17*x3  + p23*x4  + p29*x5  + p35*x6;
105         pc[5]  = m6  = p6*x1  + p12*x2  + p18*x3  + p24*x4  + p30*x5  + p36*x6;
106 
107         pc[6]  = m7  = p1*x7  + p7*x8   + p13*x9  + p19*x10 + p25*x11 + p31*x12;
108         pc[7]  = m8  = p2*x7  + p8*x8   + p14*x9  + p20*x10 + p26*x11 + p32*x12;
109         pc[8]  = m9  = p3*x7  + p9*x8   + p15*x9  + p21*x10 + p27*x11 + p33*x12;
110         pc[9]  = m10 = p4*x7  + p10*x8  + p16*x9  + p22*x10 + p28*x11 + p34*x12;
111         pc[10] = m11 = p5*x7  + p11*x8  + p17*x9  + p23*x10 + p29*x11 + p35*x12;
112         pc[11] = m12 = p6*x7  + p12*x8  + p18*x9  + p24*x10 + p30*x11 + p36*x12;
113 
114         pc[12] = m13 = p1*x13 + p7*x14  + p13*x15 + p19*x16 + p25*x17 + p31*x18;
115         pc[13] = m14 = p2*x13 + p8*x14  + p14*x15 + p20*x16 + p26*x17 + p32*x18;
116         pc[14] = m15 = p3*x13 + p9*x14  + p15*x15 + p21*x16 + p27*x17 + p33*x18;
117         pc[15] = m16 = p4*x13 + p10*x14 + p16*x15 + p22*x16 + p28*x17 + p34*x18;
118         pc[16] = m17 = p5*x13 + p11*x14 + p17*x15 + p23*x16 + p29*x17 + p35*x18;
119         pc[17] = m18 = p6*x13 + p12*x14 + p18*x15 + p24*x16 + p30*x17 + p36*x18;
120 
121         pc[18] = m19 = p1*x19 + p7*x20  + p13*x21 + p19*x22 + p25*x23 + p31*x24;
122         pc[19] = m20 = p2*x19 + p8*x20  + p14*x21 + p20*x22 + p26*x23 + p32*x24;
123         pc[20] = m21 = p3*x19 + p9*x20  + p15*x21 + p21*x22 + p27*x23 + p33*x24;
124         pc[21] = m22 = p4*x19 + p10*x20 + p16*x21 + p22*x22 + p28*x23 + p34*x24;
125         pc[22] = m23 = p5*x19 + p11*x20 + p17*x21 + p23*x22 + p29*x23 + p35*x24;
126         pc[23] = m24 = p6*x19 + p12*x20 + p18*x21 + p24*x22 + p30*x23 + p36*x24;
127 
128         pc[24] = m25 = p1*x25 + p7*x26  + p13*x27 + p19*x28 + p25*x29 + p31*x30;
129         pc[25] = m26 = p2*x25 + p8*x26  + p14*x27 + p20*x28 + p26*x29 + p32*x30;
130         pc[26] = m27 = p3*x25 + p9*x26  + p15*x27 + p21*x28 + p27*x29 + p33*x30;
131         pc[27] = m28 = p4*x25 + p10*x26 + p16*x27 + p22*x28 + p28*x29 + p34*x30;
132         pc[28] = m29 = p5*x25 + p11*x26 + p17*x27 + p23*x28 + p29*x29 + p35*x30;
133         pc[29] = m30 = p6*x25 + p12*x26 + p18*x27 + p24*x28 + p30*x29 + p36*x30;
134 
135         pc[30] = m31 = p1*x31 + p7*x32  + p13*x33 + p19*x34 + p25*x35 + p31*x36;
136         pc[31] = m32 = p2*x31 + p8*x32  + p14*x33 + p20*x34 + p26*x35 + p32*x36;
137         pc[32] = m33 = p3*x31 + p9*x32  + p15*x33 + p21*x34 + p27*x35 + p33*x36;
138         pc[33] = m34 = p4*x31 + p10*x32 + p16*x33 + p22*x34 + p28*x35 + p34*x36;
139         pc[34] = m35 = p5*x31 + p11*x32 + p17*x33 + p23*x34 + p29*x35 + p35*x36;
140         pc[35] = m36 = p6*x31 + p12*x32 + p18*x33 + p24*x34 + p30*x35 + p36*x36;
141 
142         nz = bi[row+1] - diag_offset[row] - 1;
143         pv += 36;
144         for (j=0; j<nz; j++) {
145 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
146 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
147 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
148 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
149 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
150 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
151 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
152 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
153 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
154 	  x    = rtmp + 36*pj[j];
155           x[0]  -= m1*x1  + m7*x2   + m13*x3  + m19*x4  + m25*x5  + m31*x6;
156           x[1]  -= m2*x1  + m8*x2   + m14*x3  + m20*x4  + m26*x5  + m32*x6;
157           x[2]  -= m3*x1  + m9*x2   + m15*x3  + m21*x4  + m27*x5  + m33*x6;
158           x[3]  -= m4*x1  + m10*x2  + m16*x3  + m22*x4  + m28*x5  + m34*x6;
159           x[4]  -= m5*x1  + m11*x2  + m17*x3  + m23*x4  + m29*x5  + m35*x6;
160           x[5]  -= m6*x1  + m12*x2  + m18*x3  + m24*x4  + m30*x5  + m36*x6;
161 
162 	  x[6]  -= m1*x7  + m7*x8   + m13*x9  + m19*x10 + m25*x11 + m31*x12;
163 	  x[7]  -= m2*x7  + m8*x8   + m14*x9  + m20*x10 + m26*x11 + m32*x12;
164 	  x[8]  -= m3*x7  + m9*x8   + m15*x9  + m21*x10 + m27*x11 + m33*x12;
165 	  x[9]  -= m4*x7  + m10*x8  + m16*x9  + m22*x10 + m28*x11 + m34*x12;
166 	  x[10] -= m5*x7  + m11*x8  + m17*x9  + m23*x10 + m29*x11 + m35*x12;
167 	  x[11] -= m6*x7  + m12*x8  + m18*x9  + m24*x10 + m30*x11 + m36*x12;
168 
169 	  x[12] -= m1*x13 + m7*x14  + m13*x15 + m19*x16 + m25*x17 + m31*x18;
170 	  x[13] -= m2*x13 + m8*x14  + m14*x15 + m20*x16 + m26*x17 + m32*x18;
171 	  x[14] -= m3*x13 + m9*x14  + m15*x15 + m21*x16 + m27*x17 + m33*x18;
172 	  x[15] -= m4*x13 + m10*x14 + m16*x15 + m22*x16 + m28*x17 + m34*x18;
173 	  x[16] -= m5*x13 + m11*x14 + m17*x15 + m23*x16 + m29*x17 + m35*x18;
174 	  x[17] -= m6*x13 + m12*x14 + m18*x15 + m24*x16 + m30*x17 + m36*x18;
175 
176 	  x[18] -= m1*x19 + m7*x20  + m13*x21 + m19*x22 + m25*x23 + m31*x24;
177 	  x[19] -= m2*x19 + m8*x20  + m14*x21 + m20*x22 + m26*x23 + m32*x24;
178 	  x[20] -= m3*x19 + m9*x20  + m15*x21 + m21*x22 + m27*x23 + m33*x24;
179 	  x[21] -= m4*x19 + m10*x20 + m16*x21 + m22*x22 + m28*x23 + m34*x24;
180 	  x[22] -= m5*x19 + m11*x20 + m17*x21 + m23*x22 + m29*x23 + m35*x24;
181 	  x[23] -= m6*x19 + m12*x20 + m18*x21 + m24*x22 + m30*x23 + m36*x24;
182 
183 	  x[24] -= m1*x25 + m7*x26  + m13*x27 + m19*x28 + m25*x29 + m31*x30;
184 	  x[25] -= m2*x25 + m8*x26  + m14*x27 + m20*x28 + m26*x29 + m32*x30;
185 	  x[26] -= m3*x25 + m9*x26  + m15*x27 + m21*x28 + m27*x29 + m33*x30;
186 	  x[27] -= m4*x25 + m10*x26 + m16*x27 + m22*x28 + m28*x29 + m34*x30;
187 	  x[28] -= m5*x25 + m11*x26 + m17*x27 + m23*x28 + m29*x29 + m35*x30;
188 	  x[29] -= m6*x25 + m12*x26 + m18*x27 + m24*x28 + m30*x29 + m36*x30;
189 
190 	  x[30] -= m1*x31 + m7*x32  + m13*x33 + m19*x34 + m25*x35 + m31*x36;
191 	  x[31] -= m2*x31 + m8*x32  + m14*x33 + m20*x34 + m26*x35 + m32*x36;
192 	  x[32] -= m3*x31 + m9*x32  + m15*x33 + m21*x34 + m27*x35 + m33*x36;
193 	  x[33] -= m4*x31 + m10*x32 + m16*x33 + m22*x34 + m28*x35 + m34*x36;
194 	  x[34] -= m5*x31 + m11*x32 + m17*x33 + m23*x34 + m29*x35 + m35*x36;
195 	  x[35] -= m6*x31 + m12*x32 + m18*x33 + m24*x34 + m30*x35 + m36*x36;
196 
197           pv   += 36;
198         }
199         ierr = PetscLogFlops(432.0*nz+396.0);CHKERRQ(ierr);
200       }
201       row = *ajtmp++;
202     }
203     /* finished row so stick it into b->a */
204     pv = ba + 36*bi[i];
205     pj = bj + bi[i];
206     nz = bi[i+1] - bi[i];
207     for (j=0; j<nz; j++) {
208       x      = rtmp+36*pj[j];
209       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
210       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
211       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
212       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
213       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
214       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
215       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
216       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
217       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
218       pv   += 36;
219     }
220     /* invert diagonal block */
221     w = ba + 36*diag_offset[i];
222     ierr = Kernel_A_gets_inverse_A_6(w,shift);CHKERRQ(ierr);
223   }
224 
225   ierr = PetscFree(rtmp);CHKERRQ(ierr);
226   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
227   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
228   C->ops->solve          = MatSolve_SeqBAIJ_6_inplace;
229   C->ops->solvetranspose = MatSolveTranspose_SeqBAIJ_6_inplace;
230   C->assembled = PETSC_TRUE;
231   ierr = PetscLogFlops(1.333333333333*6*6*6*b->mbs);CHKERRQ(ierr); /* from inverting diagonal blocks */
232   PetscFunctionReturn(0);
233 }
234 
235 #undef __FUNCT__
236 #define __FUNCT__ "MatLUFactorNumeric_SeqBAIJ_6"
237 PetscErrorCode MatLUFactorNumeric_SeqBAIJ_6(Mat B,Mat A,const MatFactorInfo *info)
238 {
239   Mat            C=B;
240   Mat_SeqBAIJ    *a=(Mat_SeqBAIJ*)A->data,*b=(Mat_SeqBAIJ *)C->data;
241   IS             isrow = b->row,isicol = b->icol;
242   PetscErrorCode ierr;
243   const PetscInt *r,*ic,*ics;
244   PetscInt       i,j,k,nz,nzL,row;
245   const PetscInt n=a->mbs,*ai=a->i,*aj=a->j,*bi=b->i,*bj=b->j;
246   const PetscInt *ajtmp,*bjtmp,*bdiag=b->diag,*pj,bs2=a->bs2;
247   MatScalar      *rtmp,*pc,*mwork,*v,*pv,*aa=a->a;
248   PetscInt       flg;
249   PetscReal      shift = info->shiftamount;
250 
251   PetscFunctionBegin;
252   ierr = ISGetIndices(isrow,&r);CHKERRQ(ierr);
253   ierr = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
254 
255   /* generate work space needed by the factorization */
256   ierr = PetscMalloc2(bs2*n,MatScalar,&rtmp,bs2,MatScalar,&mwork);CHKERRQ(ierr);
257   ierr = PetscMemzero(rtmp,bs2*n*sizeof(MatScalar));CHKERRQ(ierr);
258   ics  = ic;
259 
260   for (i=0; i<n; i++){
261     /* zero rtmp */
262     /* L part */
263     nz    = bi[i+1] - bi[i];
264     bjtmp = bj + bi[i];
265     for  (j=0; j<nz; j++){
266       ierr = PetscMemzero(rtmp+bs2*bjtmp[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
267     }
268 
269     /* U part */
270     nz = bdiag[i] - bdiag[i+1];
271     bjtmp = bj + bdiag[i+1]+1;
272     for  (j=0; j<nz; j++){
273       ierr = PetscMemzero(rtmp+bs2*bjtmp[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
274     }
275 
276     /* load in initial (unfactored row) */
277     nz    = ai[r[i]+1] - ai[r[i]];
278     ajtmp = aj + ai[r[i]];
279     v     = aa + bs2*ai[r[i]];
280     for (j=0; j<nz; j++) {
281       ierr = PetscMemcpy(rtmp+bs2*ic[ajtmp[j]],v+bs2*j,bs2*sizeof(MatScalar));CHKERRQ(ierr);
282     }
283 
284     /* elimination */
285     bjtmp = bj + bi[i];
286     nzL   = bi[i+1] - bi[i];
287     for(k=0;k < nzL;k++) {
288       row = bjtmp[k];
289       pc = rtmp + bs2*row;
290       for (flg=0,j=0; j<bs2; j++) { if (pc[j]!=0.0) { flg = 1; break; }}
291       if (flg) {
292         pv = b->a + bs2*bdiag[row];
293         /* Kernel_A_gets_A_times_B(bs,pc,pv,mwork); *pc = *pc * (*pv); */
294         ierr = Kernel_A_gets_A_times_B_6(pc,pv,mwork);CHKERRQ(ierr);
295 
296         pj = b->j + bdiag[row+1]+1; /* begining of U(row,:) */
297         pv = b->a + bs2*(bdiag[row+1]+1);
298         nz = bdiag[row] - bdiag[row+1] -  1; /* num of entries inU(row,:), excluding diag */
299         for (j=0; j<nz; j++) {
300           /* Kernel_A_gets_A_minus_B_times_C(bs,rtmp+bs2*pj[j],pc,pv+bs2*j); */
301           /* rtmp+bs2*pj[j] = rtmp+bs2*pj[j] - (*pc)*(pv+bs2*j) */
302           v    = rtmp + bs2*pj[j];
303           ierr = Kernel_A_gets_A_minus_B_times_C_6(v,pc,pv);CHKERRQ(ierr);
304           pv  += bs2;
305         }
306         ierr = PetscLogFlops(432*nz+396);CHKERRQ(ierr); /* flops = 2*bs^3*nz + 2*bs^3 - bs2) */
307       }
308     }
309 
310     /* finished row so stick it into b->a */
311     /* L part */
312     pv   = b->a + bs2*bi[i] ;
313     pj   = b->j + bi[i] ;
314     nz   = bi[i+1] - bi[i];
315     for (j=0; j<nz; j++) {
316       ierr = PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
317     }
318 
319     /* Mark diagonal and invert diagonal for simplier triangular solves */
320     pv   = b->a + bs2*bdiag[i];
321     pj   = b->j + bdiag[i];
322     ierr = PetscMemcpy(pv,rtmp+bs2*pj[0],bs2*sizeof(MatScalar));CHKERRQ(ierr);
323     /* ierr = Kernel_A_gets_inverse_A(bs,pv,v_pivots,v_work);CHKERRQ(ierr); */
324     ierr = Kernel_A_gets_inverse_A_6(pv,shift);CHKERRQ(ierr);
325 
326     /* U part */
327     pv = b->a + bs2*(bdiag[i+1]+1);
328     pj = b->j + bdiag[i+1]+1;
329     nz = bdiag[i] - bdiag[i+1] - 1;
330     for (j=0; j<nz; j++){
331       ierr = PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
332     }
333   }
334 
335   ierr = PetscFree2(rtmp,mwork);CHKERRQ(ierr);
336   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
337   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
338   C->ops->solve          = MatSolve_SeqBAIJ_6;
339   C->ops->solvetranspose = MatSolveTranspose_SeqBAIJ_6;
340   C->assembled = PETSC_TRUE;
341   ierr = PetscLogFlops(1.333333333333*6*6*6*n);CHKERRQ(ierr); /* from inverting diagonal blocks */
342   PetscFunctionReturn(0);
343 }
344 
345 #undef __FUNCT__
346 #define __FUNCT__ "MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering_inplace"
347 PetscErrorCode MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering_inplace(Mat C,Mat A,const MatFactorInfo *info)
348 {
349   Mat_SeqBAIJ    *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
350   PetscErrorCode ierr;
351   PetscInt       i,j,n = a->mbs,*bi = b->i,*bj = b->j;
352   PetscInt       *ajtmpold,*ajtmp,nz,row;
353   PetscInt       *diag_offset = b->diag,*ai=a->i,*aj=a->j,*pj;
354   MatScalar      *pv,*v,*rtmp,*pc,*w,*x;
355   MatScalar      x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15;
356   MatScalar      x16,x17,x18,x19,x20,x21,x22,x23,x24,x25;
357   MatScalar      p1,p2,p3,p4,p5,p6,p7,p8,p9,p10,p11,p12,p13,p14,p15;
358   MatScalar      p16,p17,p18,p19,p20,p21,p22,p23,p24,p25;
359   MatScalar      m1,m2,m3,m4,m5,m6,m7,m8,m9,m10,m11,m12,m13,m14,m15;
360   MatScalar      m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
361   MatScalar      p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
362   MatScalar      x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
363   MatScalar      m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
364   MatScalar      *ba = b->a,*aa = a->a;
365   PetscReal      shift = info->shiftamount;
366 
367   PetscFunctionBegin;
368   ierr = PetscMalloc(36*(n+1)*sizeof(MatScalar),&rtmp);CHKERRQ(ierr);
369   for (i=0; i<n; i++) {
370     nz    = bi[i+1] - bi[i];
371     ajtmp = bj + bi[i];
372     for  (j=0; j<nz; j++) {
373       x = rtmp+36*ajtmp[j];
374       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
375       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
376       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
377       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
378       x[34] = x[35] = 0.0 ;
379     }
380     /* load in initial (unfactored row) */
381     nz       = ai[i+1] - ai[i];
382     ajtmpold = aj + ai[i];
383     v        = aa + 36*ai[i];
384     for (j=0; j<nz; j++) {
385       x    = rtmp+36*ajtmpold[j];
386       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
387       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
388       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
389       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
390       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
391       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
392       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
393       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
394       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
395       v    += 36;
396     }
397     row = *ajtmp++;
398     while (row < i) {
399       pc  = rtmp + 36*row;
400       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
401       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
402       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
403       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
404       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
405       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
406       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
407       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
408       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
409       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
410           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
411           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
412           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
413           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
414           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
415           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
416           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
417           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0) {
418         pv = ba + 36*diag_offset[row];
419         pj = bj + diag_offset[row] + 1;
420 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
421 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
422 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
423 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
424 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
425 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
426 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
427 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
428 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
429         pc[0]  = m1  = p1*x1  + p7*x2   + p13*x3  + p19*x4  + p25*x5  + p31*x6;
430         pc[1]  = m2  = p2*x1  + p8*x2   + p14*x3  + p20*x4  + p26*x5  + p32*x6;
431         pc[2]  = m3  = p3*x1  + p9*x2   + p15*x3  + p21*x4  + p27*x5  + p33*x6;
432         pc[3]  = m4  = p4*x1  + p10*x2  + p16*x3  + p22*x4  + p28*x5  + p34*x6;
433         pc[4]  = m5  = p5*x1  + p11*x2  + p17*x3  + p23*x4  + p29*x5  + p35*x6;
434         pc[5]  = m6  = p6*x1  + p12*x2  + p18*x3  + p24*x4  + p30*x5  + p36*x6;
435 
436         pc[6]  = m7  = p1*x7  + p7*x8   + p13*x9  + p19*x10 + p25*x11 + p31*x12;
437         pc[7]  = m8  = p2*x7  + p8*x8   + p14*x9  + p20*x10 + p26*x11 + p32*x12;
438         pc[8]  = m9  = p3*x7  + p9*x8   + p15*x9  + p21*x10 + p27*x11 + p33*x12;
439         pc[9]  = m10 = p4*x7  + p10*x8  + p16*x9  + p22*x10 + p28*x11 + p34*x12;
440         pc[10] = m11 = p5*x7  + p11*x8  + p17*x9  + p23*x10 + p29*x11 + p35*x12;
441         pc[11] = m12 = p6*x7  + p12*x8  + p18*x9  + p24*x10 + p30*x11 + p36*x12;
442 
443         pc[12] = m13 = p1*x13 + p7*x14  + p13*x15 + p19*x16 + p25*x17 + p31*x18;
444         pc[13] = m14 = p2*x13 + p8*x14  + p14*x15 + p20*x16 + p26*x17 + p32*x18;
445         pc[14] = m15 = p3*x13 + p9*x14  + p15*x15 + p21*x16 + p27*x17 + p33*x18;
446         pc[15] = m16 = p4*x13 + p10*x14 + p16*x15 + p22*x16 + p28*x17 + p34*x18;
447         pc[16] = m17 = p5*x13 + p11*x14 + p17*x15 + p23*x16 + p29*x17 + p35*x18;
448         pc[17] = m18 = p6*x13 + p12*x14 + p18*x15 + p24*x16 + p30*x17 + p36*x18;
449 
450         pc[18] = m19 = p1*x19 + p7*x20  + p13*x21 + p19*x22 + p25*x23 + p31*x24;
451         pc[19] = m20 = p2*x19 + p8*x20  + p14*x21 + p20*x22 + p26*x23 + p32*x24;
452         pc[20] = m21 = p3*x19 + p9*x20  + p15*x21 + p21*x22 + p27*x23 + p33*x24;
453         pc[21] = m22 = p4*x19 + p10*x20 + p16*x21 + p22*x22 + p28*x23 + p34*x24;
454         pc[22] = m23 = p5*x19 + p11*x20 + p17*x21 + p23*x22 + p29*x23 + p35*x24;
455         pc[23] = m24 = p6*x19 + p12*x20 + p18*x21 + p24*x22 + p30*x23 + p36*x24;
456 
457         pc[24] = m25 = p1*x25 + p7*x26  + p13*x27 + p19*x28 + p25*x29 + p31*x30;
458         pc[25] = m26 = p2*x25 + p8*x26  + p14*x27 + p20*x28 + p26*x29 + p32*x30;
459         pc[26] = m27 = p3*x25 + p9*x26  + p15*x27 + p21*x28 + p27*x29 + p33*x30;
460         pc[27] = m28 = p4*x25 + p10*x26 + p16*x27 + p22*x28 + p28*x29 + p34*x30;
461         pc[28] = m29 = p5*x25 + p11*x26 + p17*x27 + p23*x28 + p29*x29 + p35*x30;
462         pc[29] = m30 = p6*x25 + p12*x26 + p18*x27 + p24*x28 + p30*x29 + p36*x30;
463 
464         pc[30] = m31 = p1*x31 + p7*x32  + p13*x33 + p19*x34 + p25*x35 + p31*x36;
465         pc[31] = m32 = p2*x31 + p8*x32  + p14*x33 + p20*x34 + p26*x35 + p32*x36;
466         pc[32] = m33 = p3*x31 + p9*x32  + p15*x33 + p21*x34 + p27*x35 + p33*x36;
467         pc[33] = m34 = p4*x31 + p10*x32 + p16*x33 + p22*x34 + p28*x35 + p34*x36;
468         pc[34] = m35 = p5*x31 + p11*x32 + p17*x33 + p23*x34 + p29*x35 + p35*x36;
469         pc[35] = m36 = p6*x31 + p12*x32 + p18*x33 + p24*x34 + p30*x35 + p36*x36;
470 
471         nz = bi[row+1] - diag_offset[row] - 1;
472         pv += 36;
473         for (j=0; j<nz; j++) {
474 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
475 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
476 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
477 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
478 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
479 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
480 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
481 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
482 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
483 	  x    = rtmp + 36*pj[j];
484           x[0]  -= m1*x1  + m7*x2   + m13*x3  + m19*x4  + m25*x5  + m31*x6;
485           x[1]  -= m2*x1  + m8*x2   + m14*x3  + m20*x4  + m26*x5  + m32*x6;
486           x[2]  -= m3*x1  + m9*x2   + m15*x3  + m21*x4  + m27*x5  + m33*x6;
487           x[3]  -= m4*x1  + m10*x2  + m16*x3  + m22*x4  + m28*x5  + m34*x6;
488           x[4]  -= m5*x1  + m11*x2  + m17*x3  + m23*x4  + m29*x5  + m35*x6;
489           x[5]  -= m6*x1  + m12*x2  + m18*x3  + m24*x4  + m30*x5  + m36*x6;
490 
491 	  x[6]  -= m1*x7  + m7*x8   + m13*x9  + m19*x10 + m25*x11 + m31*x12;
492 	  x[7]  -= m2*x7  + m8*x8   + m14*x9  + m20*x10 + m26*x11 + m32*x12;
493 	  x[8]  -= m3*x7  + m9*x8   + m15*x9  + m21*x10 + m27*x11 + m33*x12;
494 	  x[9]  -= m4*x7  + m10*x8  + m16*x9  + m22*x10 + m28*x11 + m34*x12;
495 	  x[10] -= m5*x7  + m11*x8  + m17*x9  + m23*x10 + m29*x11 + m35*x12;
496 	  x[11] -= m6*x7  + m12*x8  + m18*x9  + m24*x10 + m30*x11 + m36*x12;
497 
498 	  x[12] -= m1*x13 + m7*x14  + m13*x15 + m19*x16 + m25*x17 + m31*x18;
499 	  x[13] -= m2*x13 + m8*x14  + m14*x15 + m20*x16 + m26*x17 + m32*x18;
500 	  x[14] -= m3*x13 + m9*x14  + m15*x15 + m21*x16 + m27*x17 + m33*x18;
501 	  x[15] -= m4*x13 + m10*x14 + m16*x15 + m22*x16 + m28*x17 + m34*x18;
502 	  x[16] -= m5*x13 + m11*x14 + m17*x15 + m23*x16 + m29*x17 + m35*x18;
503 	  x[17] -= m6*x13 + m12*x14 + m18*x15 + m24*x16 + m30*x17 + m36*x18;
504 
505 	  x[18] -= m1*x19 + m7*x20  + m13*x21 + m19*x22 + m25*x23 + m31*x24;
506 	  x[19] -= m2*x19 + m8*x20  + m14*x21 + m20*x22 + m26*x23 + m32*x24;
507 	  x[20] -= m3*x19 + m9*x20  + m15*x21 + m21*x22 + m27*x23 + m33*x24;
508 	  x[21] -= m4*x19 + m10*x20 + m16*x21 + m22*x22 + m28*x23 + m34*x24;
509 	  x[22] -= m5*x19 + m11*x20 + m17*x21 + m23*x22 + m29*x23 + m35*x24;
510 	  x[23] -= m6*x19 + m12*x20 + m18*x21 + m24*x22 + m30*x23 + m36*x24;
511 
512 	  x[24] -= m1*x25 + m7*x26  + m13*x27 + m19*x28 + m25*x29 + m31*x30;
513 	  x[25] -= m2*x25 + m8*x26  + m14*x27 + m20*x28 + m26*x29 + m32*x30;
514 	  x[26] -= m3*x25 + m9*x26  + m15*x27 + m21*x28 + m27*x29 + m33*x30;
515 	  x[27] -= m4*x25 + m10*x26 + m16*x27 + m22*x28 + m28*x29 + m34*x30;
516 	  x[28] -= m5*x25 + m11*x26 + m17*x27 + m23*x28 + m29*x29 + m35*x30;
517 	  x[29] -= m6*x25 + m12*x26 + m18*x27 + m24*x28 + m30*x29 + m36*x30;
518 
519 	  x[30] -= m1*x31 + m7*x32  + m13*x33 + m19*x34 + m25*x35 + m31*x36;
520 	  x[31] -= m2*x31 + m8*x32  + m14*x33 + m20*x34 + m26*x35 + m32*x36;
521 	  x[32] -= m3*x31 + m9*x32  + m15*x33 + m21*x34 + m27*x35 + m33*x36;
522 	  x[33] -= m4*x31 + m10*x32 + m16*x33 + m22*x34 + m28*x35 + m34*x36;
523 	  x[34] -= m5*x31 + m11*x32 + m17*x33 + m23*x34 + m29*x35 + m35*x36;
524 	  x[35] -= m6*x31 + m12*x32 + m18*x33 + m24*x34 + m30*x35 + m36*x36;
525 
526           pv   += 36;
527         }
528         ierr = PetscLogFlops(432.0*nz+396.0);CHKERRQ(ierr);
529       }
530       row = *ajtmp++;
531     }
532     /* finished row so stick it into b->a */
533     pv = ba + 36*bi[i];
534     pj = bj + bi[i];
535     nz = bi[i+1] - bi[i];
536     for (j=0; j<nz; j++) {
537       x      = rtmp+36*pj[j];
538       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
539       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
540       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
541       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
542       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
543       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
544       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
545       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
546       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
547       pv   += 36;
548     }
549     /* invert diagonal block */
550     w = ba + 36*diag_offset[i];
551     ierr = Kernel_A_gets_inverse_A_6(w,shift);CHKERRQ(ierr);
552   }
553 
554   ierr = PetscFree(rtmp);CHKERRQ(ierr);
555   C->ops->solve          = MatSolve_SeqBAIJ_6_NaturalOrdering_inplace;
556   C->ops->solvetranspose = MatSolveTranspose_SeqBAIJ_6_NaturalOrdering_inplace;
557   C->assembled = PETSC_TRUE;
558   ierr = PetscLogFlops(1.333333333333*6*6*6*b->mbs);CHKERRQ(ierr); /* from inverting diagonal blocks */
559   PetscFunctionReturn(0);
560 }
561 
562 #undef __FUNCT__
563 #define __FUNCT__ "MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering"
564 PetscErrorCode MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering(Mat B,Mat A,const MatFactorInfo *info)
565 {
566   Mat            C=B;
567   Mat_SeqBAIJ    *a=(Mat_SeqBAIJ*)A->data,*b=(Mat_SeqBAIJ *)C->data;
568   PetscErrorCode ierr;
569   PetscInt       i,j,k,nz,nzL,row;
570   const PetscInt n=a->mbs,*ai=a->i,*aj=a->j,*bi=b->i,*bj=b->j;
571   const PetscInt *ajtmp,*bjtmp,*bdiag=b->diag,*pj,bs2=a->bs2;
572   MatScalar      *rtmp,*pc,*mwork,*v,*pv,*aa=a->a;
573   PetscInt       flg;
574   PetscReal      shift = info->shiftamount;
575 
576   PetscFunctionBegin;
577   /* generate work space needed by the factorization */
578   ierr = PetscMalloc2(bs2*n,MatScalar,&rtmp,bs2,MatScalar,&mwork);CHKERRQ(ierr);
579   ierr = PetscMemzero(rtmp,bs2*n*sizeof(MatScalar));CHKERRQ(ierr);
580 
581   for (i=0; i<n; i++){
582     /* zero rtmp */
583     /* L part */
584     nz    = bi[i+1] - bi[i];
585     bjtmp = bj + bi[i];
586     for  (j=0; j<nz; j++){
587       ierr = PetscMemzero(rtmp+bs2*bjtmp[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
588     }
589 
590     /* U part */
591     nz = bdiag[i] - bdiag[i+1];
592     bjtmp = bj + bdiag[i+1]+1;
593     for  (j=0; j<nz; j++){
594       ierr = PetscMemzero(rtmp+bs2*bjtmp[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
595     }
596 
597     /* load in initial (unfactored row) */
598     nz    = ai[i+1] - ai[i];
599     ajtmp = aj + ai[i];
600     v     = aa + bs2*ai[i];
601     for (j=0; j<nz; j++) {
602       ierr = PetscMemcpy(rtmp+bs2*ajtmp[j],v+bs2*j,bs2*sizeof(MatScalar));CHKERRQ(ierr);
603     }
604 
605     /* elimination */
606     bjtmp = bj + bi[i];
607     nzL   = bi[i+1] - bi[i];
608     for(k=0;k < nzL;k++) {
609       row = bjtmp[k];
610       pc = rtmp + bs2*row;
611       for (flg=0,j=0; j<bs2; j++) { if (pc[j]!=0.0) { flg = 1; break; }}
612       if (flg) {
613         pv = b->a + bs2*bdiag[row];
614         /* Kernel_A_gets_A_times_B(bs,pc,pv,mwork); *pc = *pc * (*pv); */
615         ierr = Kernel_A_gets_A_times_B_6(pc,pv,mwork);CHKERRQ(ierr);
616 
617         pj = b->j + bdiag[row+1]+1; /* begining of U(row,:) */
618         pv = b->a + bs2*(bdiag[row+1]+1);
619         nz = bdiag[row] - bdiag[row+1] - 1; /* num of entries inU(row,:), excluding diag */
620         for (j=0; j<nz; j++) {
621           /* Kernel_A_gets_A_minus_B_times_C(bs,rtmp+bs2*pj[j],pc,pv+bs2*j); */
622           /* rtmp+bs2*pj[j] = rtmp+bs2*pj[j] - (*pc)*(pv+bs2*j) */
623           v    = rtmp + bs2*pj[j];
624           ierr = Kernel_A_gets_A_minus_B_times_C_6(v,pc,pv);CHKERRQ(ierr);
625           pv  += bs2;
626         }
627         ierr = PetscLogFlops(432*nz+396);CHKERRQ(ierr); /* flops = 2*bs^3*nz + 2*bs^3 - bs2) */
628       }
629     }
630 
631     /* finished row so stick it into b->a */
632     /* L part */
633     pv   = b->a + bs2*bi[i] ;
634     pj   = b->j + bi[i] ;
635     nz   = bi[i+1] - bi[i];
636     for (j=0; j<nz; j++) {
637       ierr = PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
638     }
639 
640     /* Mark diagonal and invert diagonal for simplier triangular solves */
641     pv   = b->a + bs2*bdiag[i];
642     pj   = b->j + bdiag[i];
643     ierr = PetscMemcpy(pv,rtmp+bs2*pj[0],bs2*sizeof(MatScalar));CHKERRQ(ierr);
644     /* ierr = Kernel_A_gets_inverse_A(bs,pv,v_pivots,v_work);CHKERRQ(ierr); */
645     ierr = Kernel_A_gets_inverse_A_6(pv,shift);CHKERRQ(ierr);
646 
647     /* U part */
648     pv = b->a + bs2*(bdiag[i+1]+1);
649     pj = b->j + bdiag[i+1]+1;
650     nz = bdiag[i] - bdiag[i+1] - 1;
651     for (j=0; j<nz; j++){
652       ierr = PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
653     }
654   }
655   ierr = PetscFree2(rtmp,mwork);CHKERRQ(ierr);
656   C->ops->solve          = MatSolve_SeqBAIJ_6_NaturalOrdering;
657   C->ops->solvetranspose = MatSolveTranspose_SeqBAIJ_6_NaturalOrdering;
658   C->assembled = PETSC_TRUE;
659   ierr = PetscLogFlops(1.333333333333*6*6*6*n);CHKERRQ(ierr); /* from inverting diagonal blocks */
660   PetscFunctionReturn(0);
661 }
662