xref: /petsc/src/mat/impls/baij/seq/baijfact7.c (revision 2205254efee3a00a594e5e2a3a70f74dcb40bc03)
1 
2 /*
3     Factorization code for BAIJ format.
4 */
5 #include <../src/mat/impls/baij/seq/baij.h>
6 #include <../src/mat/blockinvert.h>
7 
8 /* ------------------------------------------------------------*/
9 /*
10       Version for when blocks are 6 by 6
11 */
12 #undef __FUNCT__
13 #define __FUNCT__ "MatLUFactorNumeric_SeqBAIJ_6_inplace"
14 PetscErrorCode MatLUFactorNumeric_SeqBAIJ_6_inplace(Mat C,Mat A,const MatFactorInfo *info)
15 {
16   Mat_SeqBAIJ    *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
17   IS             isrow = b->row,isicol = b->icol;
18   PetscErrorCode ierr;
19   const PetscInt *ajtmpold,*ajtmp,*diag_offset = b->diag,*r,*ic,*bi = b->i,*bj = b->j,*ai=a->i,*aj=a->j,*pj;
20   PetscInt       nz,row,i,j,n = a->mbs,idx;
21   MatScalar      *pv,*v,*rtmp,*pc,*w,*x;
22   MatScalar      p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
23   MatScalar      p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
24   MatScalar      x17,x18,x19,x20,x21,x22,x23,x24,x25,p10,p11,p12,p13,p14;
25   MatScalar      p15,p16,p17,p18,p19,p20,p21,p22,p23,p24,p25,m10,m11,m12;
26   MatScalar      m13,m14,m15,m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
27   MatScalar      p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
28   MatScalar      x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
29   MatScalar      m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
30   MatScalar      *ba = b->a,*aa = a->a;
31   PetscReal      shift = info->shiftamount;
32 
33   PetscFunctionBegin;
34   ierr = ISGetIndices(isrow,&r);CHKERRQ(ierr);
35   ierr = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
36   ierr = PetscMalloc(36*(n+1)*sizeof(MatScalar),&rtmp);CHKERRQ(ierr);
37 
38   for (i=0; i<n; i++) {
39     nz    = bi[i+1] - bi[i];
40     ajtmp = bj + bi[i];
41     for  (j=0; j<nz; j++) {
42       x = rtmp+36*ajtmp[j];
43       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
44       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
45       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
46       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
47       x[34] = x[35] = 0.0 ;
48     }
49     /* load in initial (unfactored row) */
50     idx      = r[i];
51     nz       = ai[idx+1] - ai[idx];
52     ajtmpold = aj + ai[idx];
53     v        = aa + 36*ai[idx];
54     for (j=0; j<nz; j++) {
55       x    = rtmp+36*ic[ajtmpold[j]];
56       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
57       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
58       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
59       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
60       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
61       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
62       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
63       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
64       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
65       v    += 36;
66     }
67     row = *ajtmp++;
68     while (row < i) {
69       pc  =  rtmp + 36*row;
70       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
71       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
72       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
73       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
74       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
75       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
76       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
77       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
78       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
79       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
80           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
81           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
82           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
83           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
84           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
85           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
86           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
87           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0) {
88         pv = ba + 36*diag_offset[row];
89         pj = bj + diag_offset[row] + 1;
90         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
91         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
92         x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
93         x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
94         x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
95         x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
96         x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
97         x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
98         x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
99         pc[0]  = m1  = p1*x1  + p7*x2   + p13*x3  + p19*x4  + p25*x5  + p31*x6;
100         pc[1]  = m2  = p2*x1  + p8*x2   + p14*x3  + p20*x4  + p26*x5  + p32*x6;
101         pc[2]  = m3  = p3*x1  + p9*x2   + p15*x3  + p21*x4  + p27*x5  + p33*x6;
102         pc[3]  = m4  = p4*x1  + p10*x2  + p16*x3  + p22*x4  + p28*x5  + p34*x6;
103         pc[4]  = m5  = p5*x1  + p11*x2  + p17*x3  + p23*x4  + p29*x5  + p35*x6;
104         pc[5]  = m6  = p6*x1  + p12*x2  + p18*x3  + p24*x4  + p30*x5  + p36*x6;
105 
106         pc[6]  = m7  = p1*x7  + p7*x8   + p13*x9  + p19*x10 + p25*x11 + p31*x12;
107         pc[7]  = m8  = p2*x7  + p8*x8   + p14*x9  + p20*x10 + p26*x11 + p32*x12;
108         pc[8]  = m9  = p3*x7  + p9*x8   + p15*x9  + p21*x10 + p27*x11 + p33*x12;
109         pc[9]  = m10 = p4*x7  + p10*x8  + p16*x9  + p22*x10 + p28*x11 + p34*x12;
110         pc[10] = m11 = p5*x7  + p11*x8  + p17*x9  + p23*x10 + p29*x11 + p35*x12;
111         pc[11] = m12 = p6*x7  + p12*x8  + p18*x9  + p24*x10 + p30*x11 + p36*x12;
112 
113         pc[12] = m13 = p1*x13 + p7*x14  + p13*x15 + p19*x16 + p25*x17 + p31*x18;
114         pc[13] = m14 = p2*x13 + p8*x14  + p14*x15 + p20*x16 + p26*x17 + p32*x18;
115         pc[14] = m15 = p3*x13 + p9*x14  + p15*x15 + p21*x16 + p27*x17 + p33*x18;
116         pc[15] = m16 = p4*x13 + p10*x14 + p16*x15 + p22*x16 + p28*x17 + p34*x18;
117         pc[16] = m17 = p5*x13 + p11*x14 + p17*x15 + p23*x16 + p29*x17 + p35*x18;
118         pc[17] = m18 = p6*x13 + p12*x14 + p18*x15 + p24*x16 + p30*x17 + p36*x18;
119 
120         pc[18] = m19 = p1*x19 + p7*x20  + p13*x21 + p19*x22 + p25*x23 + p31*x24;
121         pc[19] = m20 = p2*x19 + p8*x20  + p14*x21 + p20*x22 + p26*x23 + p32*x24;
122         pc[20] = m21 = p3*x19 + p9*x20  + p15*x21 + p21*x22 + p27*x23 + p33*x24;
123         pc[21] = m22 = p4*x19 + p10*x20 + p16*x21 + p22*x22 + p28*x23 + p34*x24;
124         pc[22] = m23 = p5*x19 + p11*x20 + p17*x21 + p23*x22 + p29*x23 + p35*x24;
125         pc[23] = m24 = p6*x19 + p12*x20 + p18*x21 + p24*x22 + p30*x23 + p36*x24;
126 
127         pc[24] = m25 = p1*x25 + p7*x26  + p13*x27 + p19*x28 + p25*x29 + p31*x30;
128         pc[25] = m26 = p2*x25 + p8*x26  + p14*x27 + p20*x28 + p26*x29 + p32*x30;
129         pc[26] = m27 = p3*x25 + p9*x26  + p15*x27 + p21*x28 + p27*x29 + p33*x30;
130         pc[27] = m28 = p4*x25 + p10*x26 + p16*x27 + p22*x28 + p28*x29 + p34*x30;
131         pc[28] = m29 = p5*x25 + p11*x26 + p17*x27 + p23*x28 + p29*x29 + p35*x30;
132         pc[29] = m30 = p6*x25 + p12*x26 + p18*x27 + p24*x28 + p30*x29 + p36*x30;
133 
134         pc[30] = m31 = p1*x31 + p7*x32  + p13*x33 + p19*x34 + p25*x35 + p31*x36;
135         pc[31] = m32 = p2*x31 + p8*x32  + p14*x33 + p20*x34 + p26*x35 + p32*x36;
136         pc[32] = m33 = p3*x31 + p9*x32  + p15*x33 + p21*x34 + p27*x35 + p33*x36;
137         pc[33] = m34 = p4*x31 + p10*x32 + p16*x33 + p22*x34 + p28*x35 + p34*x36;
138         pc[34] = m35 = p5*x31 + p11*x32 + p17*x33 + p23*x34 + p29*x35 + p35*x36;
139         pc[35] = m36 = p6*x31 + p12*x32 + p18*x33 + p24*x34 + p30*x35 + p36*x36;
140 
141         nz = bi[row+1] - diag_offset[row] - 1;
142         pv += 36;
143         for (j=0; j<nz; j++) {
144           x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
145           x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
146           x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
147           x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
148           x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
149           x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
150           x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
151           x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
152           x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
153           x    = rtmp + 36*pj[j];
154           x[0]  -= m1*x1  + m7*x2   + m13*x3  + m19*x4  + m25*x5  + m31*x6;
155           x[1]  -= m2*x1  + m8*x2   + m14*x3  + m20*x4  + m26*x5  + m32*x6;
156           x[2]  -= m3*x1  + m9*x2   + m15*x3  + m21*x4  + m27*x5  + m33*x6;
157           x[3]  -= m4*x1  + m10*x2  + m16*x3  + m22*x4  + m28*x5  + m34*x6;
158           x[4]  -= m5*x1  + m11*x2  + m17*x3  + m23*x4  + m29*x5  + m35*x6;
159           x[5]  -= m6*x1  + m12*x2  + m18*x3  + m24*x4  + m30*x5  + m36*x6;
160 
161           x[6]  -= m1*x7  + m7*x8   + m13*x9  + m19*x10 + m25*x11 + m31*x12;
162           x[7]  -= m2*x7  + m8*x8   + m14*x9  + m20*x10 + m26*x11 + m32*x12;
163           x[8]  -= m3*x7  + m9*x8   + m15*x9  + m21*x10 + m27*x11 + m33*x12;
164           x[9]  -= m4*x7  + m10*x8  + m16*x9  + m22*x10 + m28*x11 + m34*x12;
165           x[10] -= m5*x7  + m11*x8  + m17*x9  + m23*x10 + m29*x11 + m35*x12;
166           x[11] -= m6*x7  + m12*x8  + m18*x9  + m24*x10 + m30*x11 + m36*x12;
167 
168           x[12] -= m1*x13 + m7*x14  + m13*x15 + m19*x16 + m25*x17 + m31*x18;
169           x[13] -= m2*x13 + m8*x14  + m14*x15 + m20*x16 + m26*x17 + m32*x18;
170           x[14] -= m3*x13 + m9*x14  + m15*x15 + m21*x16 + m27*x17 + m33*x18;
171           x[15] -= m4*x13 + m10*x14 + m16*x15 + m22*x16 + m28*x17 + m34*x18;
172           x[16] -= m5*x13 + m11*x14 + m17*x15 + m23*x16 + m29*x17 + m35*x18;
173           x[17] -= m6*x13 + m12*x14 + m18*x15 + m24*x16 + m30*x17 + m36*x18;
174 
175           x[18] -= m1*x19 + m7*x20  + m13*x21 + m19*x22 + m25*x23 + m31*x24;
176           x[19] -= m2*x19 + m8*x20  + m14*x21 + m20*x22 + m26*x23 + m32*x24;
177           x[20] -= m3*x19 + m9*x20  + m15*x21 + m21*x22 + m27*x23 + m33*x24;
178           x[21] -= m4*x19 + m10*x20 + m16*x21 + m22*x22 + m28*x23 + m34*x24;
179           x[22] -= m5*x19 + m11*x20 + m17*x21 + m23*x22 + m29*x23 + m35*x24;
180           x[23] -= m6*x19 + m12*x20 + m18*x21 + m24*x22 + m30*x23 + m36*x24;
181 
182           x[24] -= m1*x25 + m7*x26  + m13*x27 + m19*x28 + m25*x29 + m31*x30;
183           x[25] -= m2*x25 + m8*x26  + m14*x27 + m20*x28 + m26*x29 + m32*x30;
184           x[26] -= m3*x25 + m9*x26  + m15*x27 + m21*x28 + m27*x29 + m33*x30;
185           x[27] -= m4*x25 + m10*x26 + m16*x27 + m22*x28 + m28*x29 + m34*x30;
186           x[28] -= m5*x25 + m11*x26 + m17*x27 + m23*x28 + m29*x29 + m35*x30;
187           x[29] -= m6*x25 + m12*x26 + m18*x27 + m24*x28 + m30*x29 + m36*x30;
188 
189           x[30] -= m1*x31 + m7*x32  + m13*x33 + m19*x34 + m25*x35 + m31*x36;
190           x[31] -= m2*x31 + m8*x32  + m14*x33 + m20*x34 + m26*x35 + m32*x36;
191           x[32] -= m3*x31 + m9*x32  + m15*x33 + m21*x34 + m27*x35 + m33*x36;
192           x[33] -= m4*x31 + m10*x32 + m16*x33 + m22*x34 + m28*x35 + m34*x36;
193           x[34] -= m5*x31 + m11*x32 + m17*x33 + m23*x34 + m29*x35 + m35*x36;
194           x[35] -= m6*x31 + m12*x32 + m18*x33 + m24*x34 + m30*x35 + m36*x36;
195 
196           pv   += 36;
197         }
198         ierr = PetscLogFlops(432.0*nz+396.0);CHKERRQ(ierr);
199       }
200       row = *ajtmp++;
201     }
202     /* finished row so stick it into b->a */
203     pv = ba + 36*bi[i];
204     pj = bj + bi[i];
205     nz = bi[i+1] - bi[i];
206     for (j=0; j<nz; j++) {
207       x      = rtmp+36*pj[j];
208       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
209       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
210       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
211       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
212       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
213       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
214       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
215       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
216       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
217       pv   += 36;
218     }
219     /* invert diagonal block */
220     w = ba + 36*diag_offset[i];
221     ierr = PetscKernel_A_gets_inverse_A_6(w,shift);CHKERRQ(ierr);
222   }
223 
224   ierr = PetscFree(rtmp);CHKERRQ(ierr);
225   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
226   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
227   C->ops->solve          = MatSolve_SeqBAIJ_6_inplace;
228   C->ops->solvetranspose = MatSolveTranspose_SeqBAIJ_6_inplace;
229   C->assembled = PETSC_TRUE;
230   ierr = PetscLogFlops(1.333333333333*6*6*6*b->mbs);CHKERRQ(ierr); /* from inverting diagonal blocks */
231   PetscFunctionReturn(0);
232 }
233 
234 #undef __FUNCT__
235 #define __FUNCT__ "MatLUFactorNumeric_SeqBAIJ_6"
236 PetscErrorCode MatLUFactorNumeric_SeqBAIJ_6(Mat B,Mat A,const MatFactorInfo *info)
237 {
238   Mat            C=B;
239   Mat_SeqBAIJ    *a=(Mat_SeqBAIJ*)A->data,*b=(Mat_SeqBAIJ *)C->data;
240   IS             isrow = b->row,isicol = b->icol;
241   PetscErrorCode ierr;
242   const PetscInt *r,*ic;
243   PetscInt       i,j,k,nz,nzL,row;
244   const PetscInt n=a->mbs,*ai=a->i,*aj=a->j,*bi=b->i,*bj=b->j;
245   const PetscInt *ajtmp,*bjtmp,*bdiag=b->diag,*pj,bs2=a->bs2;
246   MatScalar      *rtmp,*pc,*mwork,*v,*pv,*aa=a->a;
247   PetscInt       flg;
248   PetscReal      shift = info->shiftamount;
249 
250   PetscFunctionBegin;
251   ierr = ISGetIndices(isrow,&r);CHKERRQ(ierr);
252   ierr = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
253 
254   /* generate work space needed by the factorization */
255   ierr = PetscMalloc2(bs2*n,MatScalar,&rtmp,bs2,MatScalar,&mwork);CHKERRQ(ierr);
256   ierr = PetscMemzero(rtmp,bs2*n*sizeof(MatScalar));CHKERRQ(ierr);
257 
258   for (i=0; i<n; i++) {
259     /* zero rtmp */
260     /* L part */
261     nz    = bi[i+1] - bi[i];
262     bjtmp = bj + bi[i];
263     for  (j=0; j<nz; j++) {
264       ierr = PetscMemzero(rtmp+bs2*bjtmp[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
265     }
266 
267     /* U part */
268     nz = bdiag[i] - bdiag[i+1];
269     bjtmp = bj + bdiag[i+1]+1;
270     for  (j=0; j<nz; j++) {
271       ierr = PetscMemzero(rtmp+bs2*bjtmp[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
272     }
273 
274     /* load in initial (unfactored row) */
275     nz    = ai[r[i]+1] - ai[r[i]];
276     ajtmp = aj + ai[r[i]];
277     v     = aa + bs2*ai[r[i]];
278     for (j=0; j<nz; j++) {
279       ierr = PetscMemcpy(rtmp+bs2*ic[ajtmp[j]],v+bs2*j,bs2*sizeof(MatScalar));CHKERRQ(ierr);
280     }
281 
282     /* elimination */
283     bjtmp = bj + bi[i];
284     nzL   = bi[i+1] - bi[i];
285     for (k=0;k < nzL;k++) {
286       row = bjtmp[k];
287       pc = rtmp + bs2*row;
288       for (flg=0,j=0; j<bs2; j++) {
289         if (pc[j]!=0.0) {
290           flg = 1;
291           break;
292         }
293       }
294       if (flg) {
295         pv = b->a + bs2*bdiag[row];
296         /* PetscKernel_A_gets_A_times_B(bs,pc,pv,mwork); *pc = *pc * (*pv); */
297         ierr = PetscKernel_A_gets_A_times_B_6(pc,pv,mwork);CHKERRQ(ierr);
298 
299         pj = b->j + bdiag[row+1]+1; /* begining of U(row,:) */
300         pv = b->a + bs2*(bdiag[row+1]+1);
301         nz = bdiag[row] - bdiag[row+1] -  1; /* num of entries inU(row,:), excluding diag */
302         for (j=0; j<nz; j++) {
303           /* PetscKernel_A_gets_A_minus_B_times_C(bs,rtmp+bs2*pj[j],pc,pv+bs2*j); */
304           /* rtmp+bs2*pj[j] = rtmp+bs2*pj[j] - (*pc)*(pv+bs2*j) */
305           v    = rtmp + bs2*pj[j];
306           ierr = PetscKernel_A_gets_A_minus_B_times_C_6(v,pc,pv);CHKERRQ(ierr);
307           pv  += bs2;
308         }
309         ierr = PetscLogFlops(432*nz+396);CHKERRQ(ierr); /* flops = 2*bs^3*nz + 2*bs^3 - bs2) */
310       }
311     }
312 
313     /* finished row so stick it into b->a */
314     /* L part */
315     pv   = b->a + bs2*bi[i] ;
316     pj   = b->j + bi[i] ;
317     nz   = bi[i+1] - bi[i];
318     for (j=0; j<nz; j++) {
319       ierr = PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
320     }
321 
322     /* Mark diagonal and invert diagonal for simplier triangular solves */
323     pv   = b->a + bs2*bdiag[i];
324     pj   = b->j + bdiag[i];
325     ierr = PetscMemcpy(pv,rtmp+bs2*pj[0],bs2*sizeof(MatScalar));CHKERRQ(ierr);
326     /* ierr = PetscKernel_A_gets_inverse_A(bs,pv,v_pivots,v_work);CHKERRQ(ierr); */
327     ierr = PetscKernel_A_gets_inverse_A_6(pv,shift);CHKERRQ(ierr);
328 
329     /* U part */
330     pv = b->a + bs2*(bdiag[i+1]+1);
331     pj = b->j + bdiag[i+1]+1;
332     nz = bdiag[i] - bdiag[i+1] - 1;
333     for (j=0; j<nz; j++) {
334       ierr = PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
335     }
336   }
337 
338   ierr = PetscFree2(rtmp,mwork);CHKERRQ(ierr);
339   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
340   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
341   C->ops->solve          = MatSolve_SeqBAIJ_6;
342   C->ops->solvetranspose = MatSolveTranspose_SeqBAIJ_6;
343   C->assembled = PETSC_TRUE;
344   ierr = PetscLogFlops(1.333333333333*6*6*6*n);CHKERRQ(ierr); /* from inverting diagonal blocks */
345   PetscFunctionReturn(0);
346 }
347 
348 #undef __FUNCT__
349 #define __FUNCT__ "MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering_inplace"
350 PetscErrorCode MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering_inplace(Mat C,Mat A,const MatFactorInfo *info)
351 {
352   Mat_SeqBAIJ    *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
353   PetscErrorCode ierr;
354   PetscInt       i,j,n = a->mbs,*bi = b->i,*bj = b->j;
355   PetscInt       *ajtmpold,*ajtmp,nz,row;
356   PetscInt       *diag_offset = b->diag,*ai=a->i,*aj=a->j,*pj;
357   MatScalar      *pv,*v,*rtmp,*pc,*w,*x;
358   MatScalar      x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15;
359   MatScalar      x16,x17,x18,x19,x20,x21,x22,x23,x24,x25;
360   MatScalar      p1,p2,p3,p4,p5,p6,p7,p8,p9,p10,p11,p12,p13,p14,p15;
361   MatScalar      p16,p17,p18,p19,p20,p21,p22,p23,p24,p25;
362   MatScalar      m1,m2,m3,m4,m5,m6,m7,m8,m9,m10,m11,m12,m13,m14,m15;
363   MatScalar      m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
364   MatScalar      p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
365   MatScalar      x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
366   MatScalar      m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
367   MatScalar      *ba = b->a,*aa = a->a;
368   PetscReal      shift = info->shiftamount;
369 
370   PetscFunctionBegin;
371   ierr = PetscMalloc(36*(n+1)*sizeof(MatScalar),&rtmp);CHKERRQ(ierr);
372   for (i=0; i<n; i++) {
373     nz    = bi[i+1] - bi[i];
374     ajtmp = bj + bi[i];
375     for  (j=0; j<nz; j++) {
376       x = rtmp+36*ajtmp[j];
377       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
378       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
379       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
380       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
381       x[34] = x[35] = 0.0 ;
382     }
383     /* load in initial (unfactored row) */
384     nz       = ai[i+1] - ai[i];
385     ajtmpold = aj + ai[i];
386     v        = aa + 36*ai[i];
387     for (j=0; j<nz; j++) {
388       x    = rtmp+36*ajtmpold[j];
389       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
390       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
391       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
392       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
393       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
394       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
395       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
396       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
397       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
398       v    += 36;
399     }
400     row = *ajtmp++;
401     while (row < i) {
402       pc  = rtmp + 36*row;
403       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
404       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
405       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
406       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
407       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
408       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
409       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
410       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
411       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
412       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
413           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
414           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
415           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
416           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
417           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
418           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
419           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
420           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0) {
421         pv = ba + 36*diag_offset[row];
422         pj = bj + diag_offset[row] + 1;
423         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
424         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
425         x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
426         x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
427         x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
428         x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
429         x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
430         x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
431         x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
432         pc[0]  = m1  = p1*x1  + p7*x2   + p13*x3  + p19*x4  + p25*x5  + p31*x6;
433         pc[1]  = m2  = p2*x1  + p8*x2   + p14*x3  + p20*x4  + p26*x5  + p32*x6;
434         pc[2]  = m3  = p3*x1  + p9*x2   + p15*x3  + p21*x4  + p27*x5  + p33*x6;
435         pc[3]  = m4  = p4*x1  + p10*x2  + p16*x3  + p22*x4  + p28*x5  + p34*x6;
436         pc[4]  = m5  = p5*x1  + p11*x2  + p17*x3  + p23*x4  + p29*x5  + p35*x6;
437         pc[5]  = m6  = p6*x1  + p12*x2  + p18*x3  + p24*x4  + p30*x5  + p36*x6;
438 
439         pc[6]  = m7  = p1*x7  + p7*x8   + p13*x9  + p19*x10 + p25*x11 + p31*x12;
440         pc[7]  = m8  = p2*x7  + p8*x8   + p14*x9  + p20*x10 + p26*x11 + p32*x12;
441         pc[8]  = m9  = p3*x7  + p9*x8   + p15*x9  + p21*x10 + p27*x11 + p33*x12;
442         pc[9]  = m10 = p4*x7  + p10*x8  + p16*x9  + p22*x10 + p28*x11 + p34*x12;
443         pc[10] = m11 = p5*x7  + p11*x8  + p17*x9  + p23*x10 + p29*x11 + p35*x12;
444         pc[11] = m12 = p6*x7  + p12*x8  + p18*x9  + p24*x10 + p30*x11 + p36*x12;
445 
446         pc[12] = m13 = p1*x13 + p7*x14  + p13*x15 + p19*x16 + p25*x17 + p31*x18;
447         pc[13] = m14 = p2*x13 + p8*x14  + p14*x15 + p20*x16 + p26*x17 + p32*x18;
448         pc[14] = m15 = p3*x13 + p9*x14  + p15*x15 + p21*x16 + p27*x17 + p33*x18;
449         pc[15] = m16 = p4*x13 + p10*x14 + p16*x15 + p22*x16 + p28*x17 + p34*x18;
450         pc[16] = m17 = p5*x13 + p11*x14 + p17*x15 + p23*x16 + p29*x17 + p35*x18;
451         pc[17] = m18 = p6*x13 + p12*x14 + p18*x15 + p24*x16 + p30*x17 + p36*x18;
452 
453         pc[18] = m19 = p1*x19 + p7*x20  + p13*x21 + p19*x22 + p25*x23 + p31*x24;
454         pc[19] = m20 = p2*x19 + p8*x20  + p14*x21 + p20*x22 + p26*x23 + p32*x24;
455         pc[20] = m21 = p3*x19 + p9*x20  + p15*x21 + p21*x22 + p27*x23 + p33*x24;
456         pc[21] = m22 = p4*x19 + p10*x20 + p16*x21 + p22*x22 + p28*x23 + p34*x24;
457         pc[22] = m23 = p5*x19 + p11*x20 + p17*x21 + p23*x22 + p29*x23 + p35*x24;
458         pc[23] = m24 = p6*x19 + p12*x20 + p18*x21 + p24*x22 + p30*x23 + p36*x24;
459 
460         pc[24] = m25 = p1*x25 + p7*x26  + p13*x27 + p19*x28 + p25*x29 + p31*x30;
461         pc[25] = m26 = p2*x25 + p8*x26  + p14*x27 + p20*x28 + p26*x29 + p32*x30;
462         pc[26] = m27 = p3*x25 + p9*x26  + p15*x27 + p21*x28 + p27*x29 + p33*x30;
463         pc[27] = m28 = p4*x25 + p10*x26 + p16*x27 + p22*x28 + p28*x29 + p34*x30;
464         pc[28] = m29 = p5*x25 + p11*x26 + p17*x27 + p23*x28 + p29*x29 + p35*x30;
465         pc[29] = m30 = p6*x25 + p12*x26 + p18*x27 + p24*x28 + p30*x29 + p36*x30;
466 
467         pc[30] = m31 = p1*x31 + p7*x32  + p13*x33 + p19*x34 + p25*x35 + p31*x36;
468         pc[31] = m32 = p2*x31 + p8*x32  + p14*x33 + p20*x34 + p26*x35 + p32*x36;
469         pc[32] = m33 = p3*x31 + p9*x32  + p15*x33 + p21*x34 + p27*x35 + p33*x36;
470         pc[33] = m34 = p4*x31 + p10*x32 + p16*x33 + p22*x34 + p28*x35 + p34*x36;
471         pc[34] = m35 = p5*x31 + p11*x32 + p17*x33 + p23*x34 + p29*x35 + p35*x36;
472         pc[35] = m36 = p6*x31 + p12*x32 + p18*x33 + p24*x34 + p30*x35 + p36*x36;
473 
474         nz = bi[row+1] - diag_offset[row] - 1;
475         pv += 36;
476         for (j=0; j<nz; j++) {
477           x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
478           x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
479           x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
480           x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
481           x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
482           x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
483           x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
484           x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
485           x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
486           x    = rtmp + 36*pj[j];
487           x[0]  -= m1*x1  + m7*x2   + m13*x3  + m19*x4  + m25*x5  + m31*x6;
488           x[1]  -= m2*x1  + m8*x2   + m14*x3  + m20*x4  + m26*x5  + m32*x6;
489           x[2]  -= m3*x1  + m9*x2   + m15*x3  + m21*x4  + m27*x5  + m33*x6;
490           x[3]  -= m4*x1  + m10*x2  + m16*x3  + m22*x4  + m28*x5  + m34*x6;
491           x[4]  -= m5*x1  + m11*x2  + m17*x3  + m23*x4  + m29*x5  + m35*x6;
492           x[5]  -= m6*x1  + m12*x2  + m18*x3  + m24*x4  + m30*x5  + m36*x6;
493 
494           x[6]  -= m1*x7  + m7*x8   + m13*x9  + m19*x10 + m25*x11 + m31*x12;
495           x[7]  -= m2*x7  + m8*x8   + m14*x9  + m20*x10 + m26*x11 + m32*x12;
496           x[8]  -= m3*x7  + m9*x8   + m15*x9  + m21*x10 + m27*x11 + m33*x12;
497           x[9]  -= m4*x7  + m10*x8  + m16*x9  + m22*x10 + m28*x11 + m34*x12;
498           x[10] -= m5*x7  + m11*x8  + m17*x9  + m23*x10 + m29*x11 + m35*x12;
499           x[11] -= m6*x7  + m12*x8  + m18*x9  + m24*x10 + m30*x11 + m36*x12;
500 
501           x[12] -= m1*x13 + m7*x14  + m13*x15 + m19*x16 + m25*x17 + m31*x18;
502           x[13] -= m2*x13 + m8*x14  + m14*x15 + m20*x16 + m26*x17 + m32*x18;
503           x[14] -= m3*x13 + m9*x14  + m15*x15 + m21*x16 + m27*x17 + m33*x18;
504           x[15] -= m4*x13 + m10*x14 + m16*x15 + m22*x16 + m28*x17 + m34*x18;
505           x[16] -= m5*x13 + m11*x14 + m17*x15 + m23*x16 + m29*x17 + m35*x18;
506           x[17] -= m6*x13 + m12*x14 + m18*x15 + m24*x16 + m30*x17 + m36*x18;
507 
508           x[18] -= m1*x19 + m7*x20  + m13*x21 + m19*x22 + m25*x23 + m31*x24;
509           x[19] -= m2*x19 + m8*x20  + m14*x21 + m20*x22 + m26*x23 + m32*x24;
510           x[20] -= m3*x19 + m9*x20  + m15*x21 + m21*x22 + m27*x23 + m33*x24;
511           x[21] -= m4*x19 + m10*x20 + m16*x21 + m22*x22 + m28*x23 + m34*x24;
512           x[22] -= m5*x19 + m11*x20 + m17*x21 + m23*x22 + m29*x23 + m35*x24;
513           x[23] -= m6*x19 + m12*x20 + m18*x21 + m24*x22 + m30*x23 + m36*x24;
514 
515           x[24] -= m1*x25 + m7*x26  + m13*x27 + m19*x28 + m25*x29 + m31*x30;
516           x[25] -= m2*x25 + m8*x26  + m14*x27 + m20*x28 + m26*x29 + m32*x30;
517           x[26] -= m3*x25 + m9*x26  + m15*x27 + m21*x28 + m27*x29 + m33*x30;
518           x[27] -= m4*x25 + m10*x26 + m16*x27 + m22*x28 + m28*x29 + m34*x30;
519           x[28] -= m5*x25 + m11*x26 + m17*x27 + m23*x28 + m29*x29 + m35*x30;
520           x[29] -= m6*x25 + m12*x26 + m18*x27 + m24*x28 + m30*x29 + m36*x30;
521 
522           x[30] -= m1*x31 + m7*x32  + m13*x33 + m19*x34 + m25*x35 + m31*x36;
523           x[31] -= m2*x31 + m8*x32  + m14*x33 + m20*x34 + m26*x35 + m32*x36;
524           x[32] -= m3*x31 + m9*x32  + m15*x33 + m21*x34 + m27*x35 + m33*x36;
525           x[33] -= m4*x31 + m10*x32 + m16*x33 + m22*x34 + m28*x35 + m34*x36;
526           x[34] -= m5*x31 + m11*x32 + m17*x33 + m23*x34 + m29*x35 + m35*x36;
527           x[35] -= m6*x31 + m12*x32 + m18*x33 + m24*x34 + m30*x35 + m36*x36;
528 
529           pv   += 36;
530         }
531         ierr = PetscLogFlops(432.0*nz+396.0);CHKERRQ(ierr);
532       }
533       row = *ajtmp++;
534     }
535     /* finished row so stick it into b->a */
536     pv = ba + 36*bi[i];
537     pj = bj + bi[i];
538     nz = bi[i+1] - bi[i];
539     for (j=0; j<nz; j++) {
540       x      = rtmp+36*pj[j];
541       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
542       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
543       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
544       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
545       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
546       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
547       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
548       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
549       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
550       pv   += 36;
551     }
552     /* invert diagonal block */
553     w = ba + 36*diag_offset[i];
554     ierr = PetscKernel_A_gets_inverse_A_6(w,shift);CHKERRQ(ierr);
555   }
556 
557   ierr = PetscFree(rtmp);CHKERRQ(ierr);
558   C->ops->solve          = MatSolve_SeqBAIJ_6_NaturalOrdering_inplace;
559   C->ops->solvetranspose = MatSolveTranspose_SeqBAIJ_6_NaturalOrdering_inplace;
560   C->assembled = PETSC_TRUE;
561   ierr = PetscLogFlops(1.333333333333*6*6*6*b->mbs);CHKERRQ(ierr); /* from inverting diagonal blocks */
562   PetscFunctionReturn(0);
563 }
564 
565 #undef __FUNCT__
566 #define __FUNCT__ "MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering"
567 PetscErrorCode MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering(Mat B,Mat A,const MatFactorInfo *info)
568 {
569   Mat            C=B;
570   Mat_SeqBAIJ    *a=(Mat_SeqBAIJ*)A->data,*b=(Mat_SeqBAIJ *)C->data;
571   PetscErrorCode ierr;
572   PetscInt       i,j,k,nz,nzL,row;
573   const PetscInt n=a->mbs,*ai=a->i,*aj=a->j,*bi=b->i,*bj=b->j;
574   const PetscInt *ajtmp,*bjtmp,*bdiag=b->diag,*pj,bs2=a->bs2;
575   MatScalar      *rtmp,*pc,*mwork,*v,*pv,*aa=a->a;
576   PetscInt       flg;
577   PetscReal      shift = info->shiftamount;
578 
579   PetscFunctionBegin;
580   /* generate work space needed by the factorization */
581   ierr = PetscMalloc2(bs2*n,MatScalar,&rtmp,bs2,MatScalar,&mwork);CHKERRQ(ierr);
582   ierr = PetscMemzero(rtmp,bs2*n*sizeof(MatScalar));CHKERRQ(ierr);
583 
584   for (i=0; i<n; i++) {
585     /* zero rtmp */
586     /* L part */
587     nz    = bi[i+1] - bi[i];
588     bjtmp = bj + bi[i];
589     for  (j=0; j<nz; j++) {
590       ierr = PetscMemzero(rtmp+bs2*bjtmp[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
591     }
592 
593     /* U part */
594     nz = bdiag[i] - bdiag[i+1];
595     bjtmp = bj + bdiag[i+1]+1;
596     for  (j=0; j<nz; j++) {
597       ierr = PetscMemzero(rtmp+bs2*bjtmp[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
598     }
599 
600     /* load in initial (unfactored row) */
601     nz    = ai[i+1] - ai[i];
602     ajtmp = aj + ai[i];
603     v     = aa + bs2*ai[i];
604     for (j=0; j<nz; j++) {
605       ierr = PetscMemcpy(rtmp+bs2*ajtmp[j],v+bs2*j,bs2*sizeof(MatScalar));CHKERRQ(ierr);
606     }
607 
608     /* elimination */
609     bjtmp = bj + bi[i];
610     nzL   = bi[i+1] - bi[i];
611     for (k=0;k < nzL;k++) {
612       row = bjtmp[k];
613       pc = rtmp + bs2*row;
614       for (flg=0,j=0; j<bs2; j++) {
615         if (pc[j]!=0.0) {
616           flg = 1;
617           break;
618         }
619       }
620       if (flg) {
621         pv = b->a + bs2*bdiag[row];
622         /* PetscKernel_A_gets_A_times_B(bs,pc,pv,mwork); *pc = *pc * (*pv); */
623         ierr = PetscKernel_A_gets_A_times_B_6(pc,pv,mwork);CHKERRQ(ierr);
624 
625         pj = b->j + bdiag[row+1]+1; /* begining of U(row,:) */
626         pv = b->a + bs2*(bdiag[row+1]+1);
627         nz = bdiag[row] - bdiag[row+1] - 1; /* num of entries inU(row,:), excluding diag */
628         for (j=0; j<nz; j++) {
629           /* PetscKernel_A_gets_A_minus_B_times_C(bs,rtmp+bs2*pj[j],pc,pv+bs2*j); */
630           /* rtmp+bs2*pj[j] = rtmp+bs2*pj[j] - (*pc)*(pv+bs2*j) */
631           v    = rtmp + bs2*pj[j];
632           ierr = PetscKernel_A_gets_A_minus_B_times_C_6(v,pc,pv);CHKERRQ(ierr);
633           pv  += bs2;
634         }
635         ierr = PetscLogFlops(432*nz+396);CHKERRQ(ierr); /* flops = 2*bs^3*nz + 2*bs^3 - bs2) */
636       }
637     }
638 
639     /* finished row so stick it into b->a */
640     /* L part */
641     pv   = b->a + bs2*bi[i] ;
642     pj   = b->j + bi[i] ;
643     nz   = bi[i+1] - bi[i];
644     for (j=0; j<nz; j++) {
645       ierr = PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
646     }
647 
648     /* Mark diagonal and invert diagonal for simplier triangular solves */
649     pv   = b->a + bs2*bdiag[i];
650     pj   = b->j + bdiag[i];
651     ierr = PetscMemcpy(pv,rtmp+bs2*pj[0],bs2*sizeof(MatScalar));CHKERRQ(ierr);
652     /* ierr = PetscKernel_A_gets_inverse_A(bs,pv,v_pivots,v_work);CHKERRQ(ierr); */
653     ierr = PetscKernel_A_gets_inverse_A_6(pv,shift);CHKERRQ(ierr);
654 
655     /* U part */
656     pv = b->a + bs2*(bdiag[i+1]+1);
657     pj = b->j + bdiag[i+1]+1;
658     nz = bdiag[i] - bdiag[i+1] - 1;
659     for (j=0; j<nz; j++) {
660       ierr = PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
661     }
662   }
663   ierr = PetscFree2(rtmp,mwork);CHKERRQ(ierr);
664   C->ops->solve          = MatSolve_SeqBAIJ_6_NaturalOrdering;
665   C->ops->solvetranspose = MatSolveTranspose_SeqBAIJ_6_NaturalOrdering;
666   C->assembled = PETSC_TRUE;
667   ierr = PetscLogFlops(1.333333333333*6*6*6*n);CHKERRQ(ierr); /* from inverting diagonal blocks */
668   PetscFunctionReturn(0);
669 }
670