xref: /petsc/src/mat/impls/baij/seq/baijfact7.c (revision bebe2cf65d55febe21a5af8db2bd2e168caaa2e7)
1 
2 /*
3     Factorization code for BAIJ format.
4 */
5 #include <../src/mat/impls/baij/seq/baij.h>
6 #include <petsc/private/kernels/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 = PetscMalloc1(36*(n+1),&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 
228   C->ops->solve          = MatSolve_SeqBAIJ_6_inplace;
229   C->ops->solvetranspose = MatSolveTranspose_SeqBAIJ_6_inplace;
230   C->assembled           = PETSC_TRUE;
231 
232   ierr = PetscLogFlops(1.333333333333*6*6*6*b->mbs);CHKERRQ(ierr); /* from inverting diagonal blocks */
233   PetscFunctionReturn(0);
234 }
235 
236 #undef __FUNCT__
237 #define __FUNCT__ "MatLUFactorNumeric_SeqBAIJ_6"
238 PetscErrorCode MatLUFactorNumeric_SeqBAIJ_6(Mat B,Mat A,const MatFactorInfo *info)
239 {
240   Mat            C     = B;
241   Mat_SeqBAIJ    *a    = (Mat_SeqBAIJ*)A->data,*b=(Mat_SeqBAIJ*)C->data;
242   IS             isrow = b->row,isicol = b->icol;
243   PetscErrorCode ierr;
244   const PetscInt *r,*ic;
245   PetscInt       i,j,k,nz,nzL,row;
246   const PetscInt n=a->mbs,*ai=a->i,*aj=a->j,*bi=b->i,*bj=b->j;
247   const PetscInt *ajtmp,*bjtmp,*bdiag=b->diag,*pj,bs2=a->bs2;
248   MatScalar      *rtmp,*pc,*mwork,*v,*pv,*aa=a->a;
249   PetscInt       flg;
250   PetscReal      shift = info->shiftamount;
251 
252   PetscFunctionBegin;
253   ierr = ISGetIndices(isrow,&r);CHKERRQ(ierr);
254   ierr = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
255 
256   /* generate work space needed by the factorization */
257   ierr = PetscMalloc2(bs2*n,&rtmp,bs2,&mwork);CHKERRQ(ierr);
258   ierr = PetscMemzero(rtmp,bs2*n*sizeof(MatScalar));CHKERRQ(ierr);
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++) {
291         if (pc[j]!=0.0) {
292           flg = 1;
293           break;
294         }
295       }
296       if (flg) {
297         pv = b->a + bs2*bdiag[row];
298         /* PetscKernel_A_gets_A_times_B(bs,pc,pv,mwork); *pc = *pc * (*pv); */
299         ierr = PetscKernel_A_gets_A_times_B_6(pc,pv,mwork);CHKERRQ(ierr);
300 
301         pj = b->j + bdiag[row+1]+1; /* begining of U(row,:) */
302         pv = b->a + bs2*(bdiag[row+1]+1);
303         nz = bdiag[row] - bdiag[row+1] -  1; /* num of entries inU(row,:), excluding diag */
304         for (j=0; j<nz; j++) {
305           /* PetscKernel_A_gets_A_minus_B_times_C(bs,rtmp+bs2*pj[j],pc,pv+bs2*j); */
306           /* rtmp+bs2*pj[j] = rtmp+bs2*pj[j] - (*pc)*(pv+bs2*j) */
307           v    = rtmp + bs2*pj[j];
308           ierr = PetscKernel_A_gets_A_minus_B_times_C_6(v,pc,pv);CHKERRQ(ierr);
309           pv  += bs2;
310         }
311         ierr = PetscLogFlops(432*nz+396);CHKERRQ(ierr); /* flops = 2*bs^3*nz + 2*bs^3 - bs2) */
312       }
313     }
314 
315     /* finished row so stick it into b->a */
316     /* L part */
317     pv = b->a + bs2*bi[i];
318     pj = b->j + bi[i];
319     nz = bi[i+1] - bi[i];
320     for (j=0; j<nz; j++) {
321       ierr = PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
322     }
323 
324     /* Mark diagonal and invert diagonal for simplier triangular solves */
325     pv   = b->a + bs2*bdiag[i];
326     pj   = b->j + bdiag[i];
327     ierr = PetscMemcpy(pv,rtmp+bs2*pj[0],bs2*sizeof(MatScalar));CHKERRQ(ierr);
328     /* ierr = PetscKernel_A_gets_inverse_A(bs,pv,v_pivots,v_work);CHKERRQ(ierr); */
329     ierr = PetscKernel_A_gets_inverse_A_6(pv,shift);CHKERRQ(ierr);
330 
331     /* U part */
332     pv = b->a + bs2*(bdiag[i+1]+1);
333     pj = b->j + bdiag[i+1]+1;
334     nz = bdiag[i] - bdiag[i+1] - 1;
335     for (j=0; j<nz; j++) {
336       ierr = PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
337     }
338   }
339 
340   ierr = PetscFree2(rtmp,mwork);CHKERRQ(ierr);
341   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
342   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
343 
344   C->ops->solve          = MatSolve_SeqBAIJ_6;
345   C->ops->solvetranspose = MatSolveTranspose_SeqBAIJ_6;
346   C->assembled           = PETSC_TRUE;
347 
348   ierr = PetscLogFlops(1.333333333333*6*6*6*n);CHKERRQ(ierr); /* from inverting diagonal blocks */
349   PetscFunctionReturn(0);
350 }
351 
352 #undef __FUNCT__
353 #define __FUNCT__ "MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering_inplace"
354 PetscErrorCode MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering_inplace(Mat C,Mat A,const MatFactorInfo *info)
355 {
356   Mat_SeqBAIJ    *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ*)C->data;
357   PetscErrorCode ierr;
358   PetscInt       i,j,n = a->mbs,*bi = b->i,*bj = b->j;
359   PetscInt       *ajtmpold,*ajtmp,nz,row;
360   PetscInt       *diag_offset = b->diag,*ai=a->i,*aj=a->j,*pj;
361   MatScalar      *pv,*v,*rtmp,*pc,*w,*x;
362   MatScalar      x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15;
363   MatScalar      x16,x17,x18,x19,x20,x21,x22,x23,x24,x25;
364   MatScalar      p1,p2,p3,p4,p5,p6,p7,p8,p9,p10,p11,p12,p13,p14,p15;
365   MatScalar      p16,p17,p18,p19,p20,p21,p22,p23,p24,p25;
366   MatScalar      m1,m2,m3,m4,m5,m6,m7,m8,m9,m10,m11,m12,m13,m14,m15;
367   MatScalar      m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
368   MatScalar      p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
369   MatScalar      x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
370   MatScalar      m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
371   MatScalar      *ba   = b->a,*aa = a->a;
372   PetscReal      shift = info->shiftamount;
373 
374   PetscFunctionBegin;
375   ierr = PetscMalloc1(36*(n+1),&rtmp);CHKERRQ(ierr);
376   for (i=0; i<n; i++) {
377     nz    = bi[i+1] - bi[i];
378     ajtmp = bj + bi[i];
379     for  (j=0; j<nz; j++) {
380       x     = rtmp+36*ajtmp[j];
381       x[0]  = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
382       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
383       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0;
384       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0;
385       x[34] = x[35] = 0.0;
386     }
387     /* load in initial (unfactored row) */
388     nz       = ai[i+1] - ai[i];
389     ajtmpold = aj + ai[i];
390     v        = aa + 36*ai[i];
391     for (j=0; j<nz; j++) {
392       x     = rtmp+36*ajtmpold[j];
393       x[0]  =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
394       x[4]  =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
395       x[8]  =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
396       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
397       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
398       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
399       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
400       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
401       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
402       v    += 36;
403     }
404     row = *ajtmp++;
405     while (row < i) {
406       pc  = rtmp + 36*row;
407       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
408       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
409       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
410       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
411       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
412       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
413       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
414       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
415       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
416       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
417           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
418           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
419           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
420           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
421           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
422           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
423           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
424           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0) {
425         pv    = ba + 36*diag_offset[row];
426         pj    = bj + diag_offset[row] + 1;
427         x1    = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
428         x5    = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
429         x9    = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
430         x13   = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
431         x17   = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
432         x21   = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
433         x25   = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
434         x29   = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
435         x33   = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
436         pc[0] = m1  = p1*x1  + p7*x2   + p13*x3  + p19*x4  + p25*x5  + p31*x6;
437         pc[1] = m2  = p2*x1  + p8*x2   + p14*x3  + p20*x4  + p26*x5  + p32*x6;
438         pc[2] = m3  = p3*x1  + p9*x2   + p15*x3  + p21*x4  + p27*x5  + p33*x6;
439         pc[3] = m4  = p4*x1  + p10*x2  + p16*x3  + p22*x4  + p28*x5  + p34*x6;
440         pc[4] = m5  = p5*x1  + p11*x2  + p17*x3  + p23*x4  + p29*x5  + p35*x6;
441         pc[5] = m6  = p6*x1  + p12*x2  + p18*x3  + p24*x4  + p30*x5  + p36*x6;
442 
443         pc[6]  = m7  = p1*x7  + p7*x8   + p13*x9  + p19*x10 + p25*x11 + p31*x12;
444         pc[7]  = m8  = p2*x7  + p8*x8   + p14*x9  + p20*x10 + p26*x11 + p32*x12;
445         pc[8]  = m9  = p3*x7  + p9*x8   + p15*x9  + p21*x10 + p27*x11 + p33*x12;
446         pc[9]  = m10 = p4*x7  + p10*x8  + p16*x9  + p22*x10 + p28*x11 + p34*x12;
447         pc[10] = m11 = p5*x7  + p11*x8  + p17*x9  + p23*x10 + p29*x11 + p35*x12;
448         pc[11] = m12 = p6*x7  + p12*x8  + p18*x9  + p24*x10 + p30*x11 + p36*x12;
449 
450         pc[12] = m13 = p1*x13 + p7*x14  + p13*x15 + p19*x16 + p25*x17 + p31*x18;
451         pc[13] = m14 = p2*x13 + p8*x14  + p14*x15 + p20*x16 + p26*x17 + p32*x18;
452         pc[14] = m15 = p3*x13 + p9*x14  + p15*x15 + p21*x16 + p27*x17 + p33*x18;
453         pc[15] = m16 = p4*x13 + p10*x14 + p16*x15 + p22*x16 + p28*x17 + p34*x18;
454         pc[16] = m17 = p5*x13 + p11*x14 + p17*x15 + p23*x16 + p29*x17 + p35*x18;
455         pc[17] = m18 = p6*x13 + p12*x14 + p18*x15 + p24*x16 + p30*x17 + p36*x18;
456 
457         pc[18] = m19 = p1*x19 + p7*x20  + p13*x21 + p19*x22 + p25*x23 + p31*x24;
458         pc[19] = m20 = p2*x19 + p8*x20  + p14*x21 + p20*x22 + p26*x23 + p32*x24;
459         pc[20] = m21 = p3*x19 + p9*x20  + p15*x21 + p21*x22 + p27*x23 + p33*x24;
460         pc[21] = m22 = p4*x19 + p10*x20 + p16*x21 + p22*x22 + p28*x23 + p34*x24;
461         pc[22] = m23 = p5*x19 + p11*x20 + p17*x21 + p23*x22 + p29*x23 + p35*x24;
462         pc[23] = m24 = p6*x19 + p12*x20 + p18*x21 + p24*x22 + p30*x23 + p36*x24;
463 
464         pc[24] = m25 = p1*x25 + p7*x26  + p13*x27 + p19*x28 + p25*x29 + p31*x30;
465         pc[25] = m26 = p2*x25 + p8*x26  + p14*x27 + p20*x28 + p26*x29 + p32*x30;
466         pc[26] = m27 = p3*x25 + p9*x26  + p15*x27 + p21*x28 + p27*x29 + p33*x30;
467         pc[27] = m28 = p4*x25 + p10*x26 + p16*x27 + p22*x28 + p28*x29 + p34*x30;
468         pc[28] = m29 = p5*x25 + p11*x26 + p17*x27 + p23*x28 + p29*x29 + p35*x30;
469         pc[29] = m30 = p6*x25 + p12*x26 + p18*x27 + p24*x28 + p30*x29 + p36*x30;
470 
471         pc[30] = m31 = p1*x31 + p7*x32  + p13*x33 + p19*x34 + p25*x35 + p31*x36;
472         pc[31] = m32 = p2*x31 + p8*x32  + p14*x33 + p20*x34 + p26*x35 + p32*x36;
473         pc[32] = m33 = p3*x31 + p9*x32  + p15*x33 + p21*x34 + p27*x35 + p33*x36;
474         pc[33] = m34 = p4*x31 + p10*x32 + p16*x33 + p22*x34 + p28*x35 + p34*x36;
475         pc[34] = m35 = p5*x31 + p11*x32 + p17*x33 + p23*x34 + p29*x35 + p35*x36;
476         pc[35] = m36 = p6*x31 + p12*x32 + p18*x33 + p24*x34 + p30*x35 + p36*x36;
477 
478         nz  = bi[row+1] - diag_offset[row] - 1;
479         pv += 36;
480         for (j=0; j<nz; j++) {
481           x1    = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
482           x5    = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
483           x9    = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
484           x13   = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
485           x17   = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
486           x21   = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
487           x25   = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
488           x29   = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
489           x33   = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
490           x     = rtmp + 36*pj[j];
491           x[0] -= m1*x1  + m7*x2   + m13*x3  + m19*x4  + m25*x5  + m31*x6;
492           x[1] -= m2*x1  + m8*x2   + m14*x3  + m20*x4  + m26*x5  + m32*x6;
493           x[2] -= m3*x1  + m9*x2   + m15*x3  + m21*x4  + m27*x5  + m33*x6;
494           x[3] -= m4*x1  + m10*x2  + m16*x3  + m22*x4  + m28*x5  + m34*x6;
495           x[4] -= m5*x1  + m11*x2  + m17*x3  + m23*x4  + m29*x5  + m35*x6;
496           x[5] -= m6*x1  + m12*x2  + m18*x3  + m24*x4  + m30*x5  + m36*x6;
497 
498           x[6]  -= m1*x7  + m7*x8   + m13*x9  + m19*x10 + m25*x11 + m31*x12;
499           x[7]  -= m2*x7  + m8*x8   + m14*x9  + m20*x10 + m26*x11 + m32*x12;
500           x[8]  -= m3*x7  + m9*x8   + m15*x9  + m21*x10 + m27*x11 + m33*x12;
501           x[9]  -= m4*x7  + m10*x8  + m16*x9  + m22*x10 + m28*x11 + m34*x12;
502           x[10] -= m5*x7  + m11*x8  + m17*x9  + m23*x10 + m29*x11 + m35*x12;
503           x[11] -= m6*x7  + m12*x8  + m18*x9  + m24*x10 + m30*x11 + m36*x12;
504 
505           x[12] -= m1*x13 + m7*x14  + m13*x15 + m19*x16 + m25*x17 + m31*x18;
506           x[13] -= m2*x13 + m8*x14  + m14*x15 + m20*x16 + m26*x17 + m32*x18;
507           x[14] -= m3*x13 + m9*x14  + m15*x15 + m21*x16 + m27*x17 + m33*x18;
508           x[15] -= m4*x13 + m10*x14 + m16*x15 + m22*x16 + m28*x17 + m34*x18;
509           x[16] -= m5*x13 + m11*x14 + m17*x15 + m23*x16 + m29*x17 + m35*x18;
510           x[17] -= m6*x13 + m12*x14 + m18*x15 + m24*x16 + m30*x17 + m36*x18;
511 
512           x[18] -= m1*x19 + m7*x20  + m13*x21 + m19*x22 + m25*x23 + m31*x24;
513           x[19] -= m2*x19 + m8*x20  + m14*x21 + m20*x22 + m26*x23 + m32*x24;
514           x[20] -= m3*x19 + m9*x20  + m15*x21 + m21*x22 + m27*x23 + m33*x24;
515           x[21] -= m4*x19 + m10*x20 + m16*x21 + m22*x22 + m28*x23 + m34*x24;
516           x[22] -= m5*x19 + m11*x20 + m17*x21 + m23*x22 + m29*x23 + m35*x24;
517           x[23] -= m6*x19 + m12*x20 + m18*x21 + m24*x22 + m30*x23 + m36*x24;
518 
519           x[24] -= m1*x25 + m7*x26  + m13*x27 + m19*x28 + m25*x29 + m31*x30;
520           x[25] -= m2*x25 + m8*x26  + m14*x27 + m20*x28 + m26*x29 + m32*x30;
521           x[26] -= m3*x25 + m9*x26  + m15*x27 + m21*x28 + m27*x29 + m33*x30;
522           x[27] -= m4*x25 + m10*x26 + m16*x27 + m22*x28 + m28*x29 + m34*x30;
523           x[28] -= m5*x25 + m11*x26 + m17*x27 + m23*x28 + m29*x29 + m35*x30;
524           x[29] -= m6*x25 + m12*x26 + m18*x27 + m24*x28 + m30*x29 + m36*x30;
525 
526           x[30] -= m1*x31 + m7*x32  + m13*x33 + m19*x34 + m25*x35 + m31*x36;
527           x[31] -= m2*x31 + m8*x32  + m14*x33 + m20*x34 + m26*x35 + m32*x36;
528           x[32] -= m3*x31 + m9*x32  + m15*x33 + m21*x34 + m27*x35 + m33*x36;
529           x[33] -= m4*x31 + m10*x32 + m16*x33 + m22*x34 + m28*x35 + m34*x36;
530           x[34] -= m5*x31 + m11*x32 + m17*x33 + m23*x34 + m29*x35 + m35*x36;
531           x[35] -= m6*x31 + m12*x32 + m18*x33 + m24*x34 + m30*x35 + m36*x36;
532 
533           pv += 36;
534         }
535         ierr = PetscLogFlops(432.0*nz+396.0);CHKERRQ(ierr);
536       }
537       row = *ajtmp++;
538     }
539     /* finished row so stick it into b->a */
540     pv = ba + 36*bi[i];
541     pj = bj + bi[i];
542     nz = bi[i+1] - bi[i];
543     for (j=0; j<nz; j++) {
544       x      = rtmp+36*pj[j];
545       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
546       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
547       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
548       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
549       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
550       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
551       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
552       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
553       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
554       pv    += 36;
555     }
556     /* invert diagonal block */
557     w    = ba + 36*diag_offset[i];
558     ierr = PetscKernel_A_gets_inverse_A_6(w,shift);CHKERRQ(ierr);
559   }
560 
561   ierr = PetscFree(rtmp);CHKERRQ(ierr);
562 
563   C->ops->solve          = MatSolve_SeqBAIJ_6_NaturalOrdering_inplace;
564   C->ops->solvetranspose = MatSolveTranspose_SeqBAIJ_6_NaturalOrdering_inplace;
565   C->assembled           = PETSC_TRUE;
566 
567   ierr = PetscLogFlops(1.333333333333*6*6*6*b->mbs);CHKERRQ(ierr); /* from inverting diagonal blocks */
568   PetscFunctionReturn(0);
569 }
570 
571 #undef __FUNCT__
572 #define __FUNCT__ "MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering"
573 PetscErrorCode MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering(Mat B,Mat A,const MatFactorInfo *info)
574 {
575   Mat            C =B;
576   Mat_SeqBAIJ    *a=(Mat_SeqBAIJ*)A->data,*b=(Mat_SeqBAIJ*)C->data;
577   PetscErrorCode ierr;
578   PetscInt       i,j,k,nz,nzL,row;
579   const PetscInt n=a->mbs,*ai=a->i,*aj=a->j,*bi=b->i,*bj=b->j;
580   const PetscInt *ajtmp,*bjtmp,*bdiag=b->diag,*pj,bs2=a->bs2;
581   MatScalar      *rtmp,*pc,*mwork,*v,*pv,*aa=a->a;
582   PetscInt       flg;
583   PetscReal      shift = info->shiftamount;
584 
585   PetscFunctionBegin;
586   /* generate work space needed by the factorization */
587   ierr = PetscMalloc2(bs2*n,&rtmp,bs2,&mwork);CHKERRQ(ierr);
588   ierr = PetscMemzero(rtmp,bs2*n*sizeof(MatScalar));CHKERRQ(ierr);
589 
590   for (i=0; i<n; i++) {
591     /* zero rtmp */
592     /* L part */
593     nz    = bi[i+1] - bi[i];
594     bjtmp = bj + bi[i];
595     for  (j=0; j<nz; j++) {
596       ierr = PetscMemzero(rtmp+bs2*bjtmp[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
597     }
598 
599     /* U part */
600     nz    = bdiag[i] - bdiag[i+1];
601     bjtmp = bj + bdiag[i+1]+1;
602     for  (j=0; j<nz; j++) {
603       ierr = PetscMemzero(rtmp+bs2*bjtmp[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
604     }
605 
606     /* load in initial (unfactored row) */
607     nz    = ai[i+1] - ai[i];
608     ajtmp = aj + ai[i];
609     v     = aa + bs2*ai[i];
610     for (j=0; j<nz; j++) {
611       ierr = PetscMemcpy(rtmp+bs2*ajtmp[j],v+bs2*j,bs2*sizeof(MatScalar));CHKERRQ(ierr);
612     }
613 
614     /* elimination */
615     bjtmp = bj + bi[i];
616     nzL   = bi[i+1] - bi[i];
617     for (k=0; k < nzL; k++) {
618       row = bjtmp[k];
619       pc  = rtmp + bs2*row;
620       for (flg=0,j=0; j<bs2; j++) {
621         if (pc[j]!=0.0) {
622           flg = 1;
623           break;
624         }
625       }
626       if (flg) {
627         pv = b->a + bs2*bdiag[row];
628         /* PetscKernel_A_gets_A_times_B(bs,pc,pv,mwork); *pc = *pc * (*pv); */
629         ierr = PetscKernel_A_gets_A_times_B_6(pc,pv,mwork);CHKERRQ(ierr);
630 
631         pj = b->j + bdiag[row+1]+1; /* begining of U(row,:) */
632         pv = b->a + bs2*(bdiag[row+1]+1);
633         nz = bdiag[row] - bdiag[row+1] - 1; /* num of entries inU(row,:), excluding diag */
634         for (j=0; j<nz; j++) {
635           /* PetscKernel_A_gets_A_minus_B_times_C(bs,rtmp+bs2*pj[j],pc,pv+bs2*j); */
636           /* rtmp+bs2*pj[j] = rtmp+bs2*pj[j] - (*pc)*(pv+bs2*j) */
637           v    = rtmp + bs2*pj[j];
638           ierr = PetscKernel_A_gets_A_minus_B_times_C_6(v,pc,pv);CHKERRQ(ierr);
639           pv  += bs2;
640         }
641         ierr = PetscLogFlops(432*nz+396);CHKERRQ(ierr); /* flops = 2*bs^3*nz + 2*bs^3 - bs2) */
642       }
643     }
644 
645     /* finished row so stick it into b->a */
646     /* L part */
647     pv = b->a + bs2*bi[i];
648     pj = b->j + bi[i];
649     nz = bi[i+1] - bi[i];
650     for (j=0; j<nz; j++) {
651       ierr = PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
652     }
653 
654     /* Mark diagonal and invert diagonal for simplier triangular solves */
655     pv   = b->a + bs2*bdiag[i];
656     pj   = b->j + bdiag[i];
657     ierr = PetscMemcpy(pv,rtmp+bs2*pj[0],bs2*sizeof(MatScalar));CHKERRQ(ierr);
658     /* ierr = PetscKernel_A_gets_inverse_A(bs,pv,v_pivots,v_work);CHKERRQ(ierr); */
659     ierr = PetscKernel_A_gets_inverse_A_6(pv,shift);CHKERRQ(ierr);
660 
661     /* U part */
662     pv = b->a + bs2*(bdiag[i+1]+1);
663     pj = b->j + bdiag[i+1]+1;
664     nz = bdiag[i] - bdiag[i+1] - 1;
665     for (j=0; j<nz; j++) {
666       ierr = PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
667     }
668   }
669   ierr = PetscFree2(rtmp,mwork);CHKERRQ(ierr);
670 
671   C->ops->solve          = MatSolve_SeqBAIJ_6_NaturalOrdering;
672   C->ops->solvetranspose = MatSolveTranspose_SeqBAIJ_6_NaturalOrdering;
673   C->assembled           = PETSC_TRUE;
674 
675   ierr = PetscLogFlops(1.333333333333*6*6*6*n);CHKERRQ(ierr); /* from inverting diagonal blocks */
676   PetscFunctionReturn(0);
677 }
678