xref: /petsc/src/mat/impls/baij/seq/baijfact11.c (revision 6849ba73f22fecb8f92ef896a42e4e8bd4cd6965)
1 /*
2     Factorization code for BAIJ format.
3 */
4 #include "src/mat/impls/baij/seq/baij.h"
5 #include "src/inline/ilu.h"
6 
7 /* ------------------------------------------------------------*/
8 /*
9       Version for when blocks are 4 by 4
10 */
11 #undef __FUNCT__
12 #define __FUNCT__ "MatLUFactorNumeric_SeqBAIJ_4"
13 PetscErrorCode MatLUFactorNumeric_SeqBAIJ_4(Mat A,Mat *B)
14 {
15   Mat         C = *B;
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   int         *r,*ic,i,j,n = a->mbs,*bi = b->i,*bj = b->j;
20   int         *ajtmpold,*ajtmp,nz,row;
21   int         *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j,*pj;
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   p10,p11,p12,p13,p14,p15,p16,m10,m11,m12;
26   MatScalar   m13,m14,m15,m16;
27   MatScalar   *ba = b->a,*aa = a->a;
28   PetscTruth  pivotinblocks = b->pivotinblocks;
29 
30   PetscFunctionBegin;
31   ierr = ISGetIndices(isrow,&r);CHKERRQ(ierr);
32   ierr = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
33   ierr = PetscMalloc(16*(n+1)*sizeof(MatScalar),&rtmp);CHKERRQ(ierr);
34 
35   for (i=0; i<n; i++) {
36     nz    = bi[i+1] - bi[i];
37     ajtmp = bj + bi[i];
38     for  (j=0; j<nz; j++) {
39       x = rtmp+16*ajtmp[j];
40       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = x[9] = 0.0;
41       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = 0.0;
42     }
43     /* load in initial (unfactored row) */
44     idx      = r[i];
45     nz       = ai[idx+1] - ai[idx];
46     ajtmpold = aj + ai[idx];
47     v        = aa + 16*ai[idx];
48     for (j=0; j<nz; j++) {
49       x    = rtmp+16*ic[ajtmpold[j]];
50       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
51       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
52       x[9]  = v[9];  x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
53       x[14] = v[14]; x[15] = v[15];
54       v    += 16;
55     }
56     row = *ajtmp++;
57     while (row < i) {
58       pc  = rtmp + 16*row;
59       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
60       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
61       p10 = pc[9];  p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
62       p15 = pc[14]; p16 = pc[15];
63       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
64           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
65           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
66           || p16 != 0.0) {
67         pv = ba + 16*diag_offset[row];
68         pj = bj + diag_offset[row] + 1;
69         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
70         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
71         x10 = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
72         x15 = pv[14]; x16 = pv[15];
73         pc[0] = m1 = p1*x1 + p5*x2  + p9*x3  + p13*x4;
74         pc[1] = m2 = p2*x1 + p6*x2  + p10*x3 + p14*x4;
75         pc[2] = m3 = p3*x1 + p7*x2  + p11*x3 + p15*x4;
76         pc[3] = m4 = p4*x1 + p8*x2  + p12*x3 + p16*x4;
77 
78         pc[4] = m5 = p1*x5 + p5*x6  + p9*x7  + p13*x8;
79         pc[5] = m6 = p2*x5 + p6*x6  + p10*x7 + p14*x8;
80         pc[6] = m7 = p3*x5 + p7*x6  + p11*x7 + p15*x8;
81         pc[7] = m8 = p4*x5 + p8*x6  + p12*x7 + p16*x8;
82 
83         pc[8]  = m9  = p1*x9 + p5*x10  + p9*x11  + p13*x12;
84         pc[9]  = m10 = p2*x9 + p6*x10  + p10*x11 + p14*x12;
85         pc[10] = m11 = p3*x9 + p7*x10  + p11*x11 + p15*x12;
86         pc[11] = m12 = p4*x9 + p8*x10  + p12*x11 + p16*x12;
87 
88         pc[12] = m13 = p1*x13 + p5*x14  + p9*x15  + p13*x16;
89         pc[13] = m14 = p2*x13 + p6*x14  + p10*x15 + p14*x16;
90         pc[14] = m15 = p3*x13 + p7*x14  + p11*x15 + p15*x16;
91         pc[15] = m16 = p4*x13 + p8*x14  + p12*x15 + p16*x16;
92 
93         nz = bi[row+1] - diag_offset[row] - 1;
94         pv += 16;
95         for (j=0; j<nz; j++) {
96           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
97           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
98           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
99           x14  = pv[13]; x15 = pv[14]; x16 = pv[15];
100           x    = rtmp + 16*pj[j];
101           x[0] -= m1*x1 + m5*x2  + m9*x3  + m13*x4;
102           x[1] -= m2*x1 + m6*x2  + m10*x3 + m14*x4;
103           x[2] -= m3*x1 + m7*x2  + m11*x3 + m15*x4;
104           x[3] -= m4*x1 + m8*x2  + m12*x3 + m16*x4;
105 
106           x[4] -= m1*x5 + m5*x6  + m9*x7  + m13*x8;
107           x[5] -= m2*x5 + m6*x6  + m10*x7 + m14*x8;
108           x[6] -= m3*x5 + m7*x6  + m11*x7 + m15*x8;
109           x[7] -= m4*x5 + m8*x6  + m12*x7 + m16*x8;
110 
111           x[8]  -= m1*x9 + m5*x10 + m9*x11  + m13*x12;
112           x[9]  -= m2*x9 + m6*x10 + m10*x11 + m14*x12;
113           x[10] -= m3*x9 + m7*x10 + m11*x11 + m15*x12;
114           x[11] -= m4*x9 + m8*x10 + m12*x11 + m16*x12;
115 
116           x[12] -= m1*x13 + m5*x14  + m9*x15  + m13*x16;
117           x[13] -= m2*x13 + m6*x14  + m10*x15 + m14*x16;
118           x[14] -= m3*x13 + m7*x14  + m11*x15 + m15*x16;
119           x[15] -= m4*x13 + m8*x14  + m12*x15 + m16*x16;
120 
121           pv   += 16;
122         }
123         PetscLogFlops(128*nz+112);
124       }
125       row = *ajtmp++;
126     }
127     /* finished row so stick it into b->a */
128     pv = ba + 16*bi[i];
129     pj = bj + bi[i];
130     nz = bi[i+1] - bi[i];
131     for (j=0; j<nz; j++) {
132       x      = rtmp+16*pj[j];
133       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
134       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
135       pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
136       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
137       pv   += 16;
138     }
139     /* invert diagonal block */
140     w    = ba + 16*diag_offset[i];
141     if (pivotinblocks) {
142       ierr = Kernel_A_gets_inverse_A_4(w);CHKERRQ(ierr);
143     } else {
144       ierr = Kernel_A_gets_inverse_A_4_nopivot(w);CHKERRQ(ierr);
145     }
146   }
147 
148   ierr = PetscFree(rtmp);CHKERRQ(ierr);
149   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
150   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
151   C->factor = FACTOR_LU;
152   C->assembled = PETSC_TRUE;
153   PetscLogFlops(1.3333*64*b->mbs); /* from inverting diagonal blocks */
154   PetscFunctionReturn(0);
155 }
156