xref: /petsc/src/mat/impls/baij/seq/baijfact7.c (revision e8c0849ab8fe171bed529bea27238c9b402db591)
1 /*
2     Factorization code for BAIJ format.
3 */
4 #include <../src/mat/impls/baij/seq/baij.h>
5 #include <petsc/private/kernels/blockinvert.h>
6 
7 /*
8       Version for when blocks are 6 by 6
9 */
MatILUFactorNumeric_SeqBAIJ_6_inplace(Mat C,Mat A,const MatFactorInfo * info)10 PetscErrorCode MatILUFactorNumeric_SeqBAIJ_6_inplace(Mat C, Mat A, const MatFactorInfo *info)
11 {
12   Mat_SeqBAIJ    *a = (Mat_SeqBAIJ *)A->data, *b = (Mat_SeqBAIJ *)C->data;
13   IS              isrow = b->row, isicol = b->icol;
14   const PetscInt *ajtmpold, *ajtmp, *diag_offset = b->diag, *r, *ic, *bi = b->i, *bj = b->j, *ai = a->i, *aj = a->j, *pj;
15   PetscInt        nz, row, i, j, n = a->mbs, idx;
16   MatScalar      *pv, *v, *rtmp, *pc, *w, *x;
17   MatScalar       p1, p2, p3, p4, m1, m2, m3, m4, m5, m6, m7, m8, m9, x1, x2, x3, x4;
18   MatScalar       p5, p6, p7, p8, p9, x5, x6, x7, x8, x9, x10, x11, x12, x13, x14, x15, x16;
19   MatScalar       x17, x18, x19, x20, x21, x22, x23, x24, x25, p10, p11, p12, p13, p14;
20   MatScalar       p15, p16, p17, p18, p19, p20, p21, p22, p23, p24, p25, m10, m11, m12;
21   MatScalar       m13, m14, m15, m16, m17, m18, m19, m20, m21, m22, m23, m24, m25;
22   MatScalar       p26, p27, p28, p29, p30, p31, p32, p33, p34, p35, p36;
23   MatScalar       x26, x27, x28, x29, x30, x31, x32, x33, x34, x35, x36;
24   MatScalar       m26, m27, m28, m29, m30, m31, m32, m33, m34, m35, m36;
25   MatScalar      *ba = b->a, *aa = a->a;
26   PetscReal       shift = info->shiftamount;
27   PetscBool       allowzeropivot, zeropivotdetected;
28 
29   PetscFunctionBegin;
30   /* Since A is C and C is labeled as a factored matrix we need to lie to MatGetDiagonalMarkers_SeqBAIJ() to get it to compute the diagonals */
31   A->factortype = MAT_FACTOR_NONE;
32   PetscCall(MatGetDiagonalMarkers_SeqBAIJ(A, &diag_offset, NULL));
33   A->factortype  = MAT_FACTOR_ILU;
34   allowzeropivot = PetscNot(A->erroriffailure);
35   PetscCall(ISGetIndices(isrow, &r));
36   PetscCall(ISGetIndices(isicol, &ic));
37   PetscCall(PetscMalloc1(36 * (n + 1), &rtmp));
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];
58       x[1]  = v[1];
59       x[2]  = v[2];
60       x[3]  = v[3];
61       x[4]  = v[4];
62       x[5]  = v[5];
63       x[6]  = v[6];
64       x[7]  = v[7];
65       x[8]  = v[8];
66       x[9]  = v[9];
67       x[10] = v[10];
68       x[11] = v[11];
69       x[12] = v[12];
70       x[13] = v[13];
71       x[14] = v[14];
72       x[15] = v[15];
73       x[16] = v[16];
74       x[17] = v[17];
75       x[18] = v[18];
76       x[19] = v[19];
77       x[20] = v[20];
78       x[21] = v[21];
79       x[22] = v[22];
80       x[23] = v[23];
81       x[24] = v[24];
82       x[25] = v[25];
83       x[26] = v[26];
84       x[27] = v[27];
85       x[28] = v[28];
86       x[29] = v[29];
87       x[30] = v[30];
88       x[31] = v[31];
89       x[32] = v[32];
90       x[33] = v[33];
91       x[34] = v[34];
92       x[35] = v[35];
93       v += 36;
94     }
95     row = *ajtmp++;
96     while (row < i) {
97       pc  = rtmp + 36 * row;
98       p1  = pc[0];
99       p2  = pc[1];
100       p3  = pc[2];
101       p4  = pc[3];
102       p5  = pc[4];
103       p6  = pc[5];
104       p7  = pc[6];
105       p8  = pc[7];
106       p9  = pc[8];
107       p10 = pc[9];
108       p11 = pc[10];
109       p12 = pc[11];
110       p13 = pc[12];
111       p14 = pc[13];
112       p15 = pc[14];
113       p16 = pc[15];
114       p17 = pc[16];
115       p18 = pc[17];
116       p19 = pc[18];
117       p20 = pc[19];
118       p21 = pc[20];
119       p22 = pc[21];
120       p23 = pc[22];
121       p24 = pc[23];
122       p25 = pc[24];
123       p26 = pc[25];
124       p27 = pc[26];
125       p28 = pc[27];
126       p29 = pc[28];
127       p30 = pc[29];
128       p31 = pc[30];
129       p32 = pc[31];
130       p33 = pc[32];
131       p34 = pc[33];
132       p35 = pc[34];
133       p36 = pc[35];
134       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 || p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 || p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 || p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 || p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 || p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 || p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0) {
135         pv    = ba + 36 * diag_offset[row];
136         pj    = bj + diag_offset[row] + 1;
137         x1    = pv[0];
138         x2    = pv[1];
139         x3    = pv[2];
140         x4    = pv[3];
141         x5    = pv[4];
142         x6    = pv[5];
143         x7    = pv[6];
144         x8    = pv[7];
145         x9    = pv[8];
146         x10   = pv[9];
147         x11   = pv[10];
148         x12   = pv[11];
149         x13   = pv[12];
150         x14   = pv[13];
151         x15   = pv[14];
152         x16   = pv[15];
153         x17   = pv[16];
154         x18   = pv[17];
155         x19   = pv[18];
156         x20   = pv[19];
157         x21   = pv[20];
158         x22   = pv[21];
159         x23   = pv[22];
160         x24   = pv[23];
161         x25   = pv[24];
162         x26   = pv[25];
163         x27   = pv[26];
164         x28   = pv[27];
165         x29   = pv[28];
166         x30   = pv[29];
167         x31   = pv[30];
168         x32   = pv[31];
169         x33   = pv[32];
170         x34   = pv[33];
171         x35   = pv[34];
172         x36   = pv[35];
173         pc[0] = m1 = p1 * x1 + p7 * x2 + p13 * x3 + p19 * x4 + p25 * x5 + p31 * x6;
174         pc[1] = m2 = p2 * x1 + p8 * x2 + p14 * x3 + p20 * x4 + p26 * x5 + p32 * x6;
175         pc[2] = m3 = p3 * x1 + p9 * x2 + p15 * x3 + p21 * x4 + p27 * x5 + p33 * x6;
176         pc[3] = m4 = p4 * x1 + p10 * x2 + p16 * x3 + p22 * x4 + p28 * x5 + p34 * x6;
177         pc[4] = m5 = p5 * x1 + p11 * x2 + p17 * x3 + p23 * x4 + p29 * x5 + p35 * x6;
178         pc[5] = m6 = p6 * x1 + p12 * x2 + p18 * x3 + p24 * x4 + p30 * x5 + p36 * x6;
179 
180         pc[6] = m7 = p1 * x7 + p7 * x8 + p13 * x9 + p19 * x10 + p25 * x11 + p31 * x12;
181         pc[7] = m8 = p2 * x7 + p8 * x8 + p14 * x9 + p20 * x10 + p26 * x11 + p32 * x12;
182         pc[8] = m9 = p3 * x7 + p9 * x8 + p15 * x9 + p21 * x10 + p27 * x11 + p33 * x12;
183         pc[9] = m10 = p4 * x7 + p10 * x8 + p16 * x9 + p22 * x10 + p28 * x11 + p34 * x12;
184         pc[10] = m11 = p5 * x7 + p11 * x8 + p17 * x9 + p23 * x10 + p29 * x11 + p35 * x12;
185         pc[11] = m12 = p6 * x7 + p12 * x8 + p18 * x9 + p24 * x10 + p30 * x11 + p36 * x12;
186 
187         pc[12] = m13 = p1 * x13 + p7 * x14 + p13 * x15 + p19 * x16 + p25 * x17 + p31 * x18;
188         pc[13] = m14 = p2 * x13 + p8 * x14 + p14 * x15 + p20 * x16 + p26 * x17 + p32 * x18;
189         pc[14] = m15 = p3 * x13 + p9 * x14 + p15 * x15 + p21 * x16 + p27 * x17 + p33 * x18;
190         pc[15] = m16 = p4 * x13 + p10 * x14 + p16 * x15 + p22 * x16 + p28 * x17 + p34 * x18;
191         pc[16] = m17 = p5 * x13 + p11 * x14 + p17 * x15 + p23 * x16 + p29 * x17 + p35 * x18;
192         pc[17] = m18 = p6 * x13 + p12 * x14 + p18 * x15 + p24 * x16 + p30 * x17 + p36 * x18;
193 
194         pc[18] = m19 = p1 * x19 + p7 * x20 + p13 * x21 + p19 * x22 + p25 * x23 + p31 * x24;
195         pc[19] = m20 = p2 * x19 + p8 * x20 + p14 * x21 + p20 * x22 + p26 * x23 + p32 * x24;
196         pc[20] = m21 = p3 * x19 + p9 * x20 + p15 * x21 + p21 * x22 + p27 * x23 + p33 * x24;
197         pc[21] = m22 = p4 * x19 + p10 * x20 + p16 * x21 + p22 * x22 + p28 * x23 + p34 * x24;
198         pc[22] = m23 = p5 * x19 + p11 * x20 + p17 * x21 + p23 * x22 + p29 * x23 + p35 * x24;
199         pc[23] = m24 = p6 * x19 + p12 * x20 + p18 * x21 + p24 * x22 + p30 * x23 + p36 * x24;
200 
201         pc[24] = m25 = p1 * x25 + p7 * x26 + p13 * x27 + p19 * x28 + p25 * x29 + p31 * x30;
202         pc[25] = m26 = p2 * x25 + p8 * x26 + p14 * x27 + p20 * x28 + p26 * x29 + p32 * x30;
203         pc[26] = m27 = p3 * x25 + p9 * x26 + p15 * x27 + p21 * x28 + p27 * x29 + p33 * x30;
204         pc[27] = m28 = p4 * x25 + p10 * x26 + p16 * x27 + p22 * x28 + p28 * x29 + p34 * x30;
205         pc[28] = m29 = p5 * x25 + p11 * x26 + p17 * x27 + p23 * x28 + p29 * x29 + p35 * x30;
206         pc[29] = m30 = p6 * x25 + p12 * x26 + p18 * x27 + p24 * x28 + p30 * x29 + p36 * x30;
207 
208         pc[30] = m31 = p1 * x31 + p7 * x32 + p13 * x33 + p19 * x34 + p25 * x35 + p31 * x36;
209         pc[31] = m32 = p2 * x31 + p8 * x32 + p14 * x33 + p20 * x34 + p26 * x35 + p32 * x36;
210         pc[32] = m33 = p3 * x31 + p9 * x32 + p15 * x33 + p21 * x34 + p27 * x35 + p33 * x36;
211         pc[33] = m34 = p4 * x31 + p10 * x32 + p16 * x33 + p22 * x34 + p28 * x35 + p34 * x36;
212         pc[34] = m35 = p5 * x31 + p11 * x32 + p17 * x33 + p23 * x34 + p29 * x35 + p35 * x36;
213         pc[35] = m36 = p6 * x31 + p12 * x32 + p18 * x33 + p24 * x34 + p30 * x35 + p36 * x36;
214 
215         nz = bi[row + 1] - diag_offset[row] - 1;
216         pv += 36;
217         for (j = 0; j < nz; j++) {
218           x1  = pv[0];
219           x2  = pv[1];
220           x3  = pv[2];
221           x4  = pv[3];
222           x5  = pv[4];
223           x6  = pv[5];
224           x7  = pv[6];
225           x8  = pv[7];
226           x9  = pv[8];
227           x10 = pv[9];
228           x11 = pv[10];
229           x12 = pv[11];
230           x13 = pv[12];
231           x14 = pv[13];
232           x15 = pv[14];
233           x16 = pv[15];
234           x17 = pv[16];
235           x18 = pv[17];
236           x19 = pv[18];
237           x20 = pv[19];
238           x21 = pv[20];
239           x22 = pv[21];
240           x23 = pv[22];
241           x24 = pv[23];
242           x25 = pv[24];
243           x26 = pv[25];
244           x27 = pv[26];
245           x28 = pv[27];
246           x29 = pv[28];
247           x30 = pv[29];
248           x31 = pv[30];
249           x32 = pv[31];
250           x33 = pv[32];
251           x34 = pv[33];
252           x35 = pv[34];
253           x36 = pv[35];
254           x   = rtmp + 36 * pj[j];
255           x[0] -= m1 * x1 + m7 * x2 + m13 * x3 + m19 * x4 + m25 * x5 + m31 * x6;
256           x[1] -= m2 * x1 + m8 * x2 + m14 * x3 + m20 * x4 + m26 * x5 + m32 * x6;
257           x[2] -= m3 * x1 + m9 * x2 + m15 * x3 + m21 * x4 + m27 * x5 + m33 * x6;
258           x[3] -= m4 * x1 + m10 * x2 + m16 * x3 + m22 * x4 + m28 * x5 + m34 * x6;
259           x[4] -= m5 * x1 + m11 * x2 + m17 * x3 + m23 * x4 + m29 * x5 + m35 * x6;
260           x[5] -= m6 * x1 + m12 * x2 + m18 * x3 + m24 * x4 + m30 * x5 + m36 * x6;
261 
262           x[6] -= m1 * x7 + m7 * x8 + m13 * x9 + m19 * x10 + m25 * x11 + m31 * x12;
263           x[7] -= m2 * x7 + m8 * x8 + m14 * x9 + m20 * x10 + m26 * x11 + m32 * x12;
264           x[8] -= m3 * x7 + m9 * x8 + m15 * x9 + m21 * x10 + m27 * x11 + m33 * x12;
265           x[9] -= m4 * x7 + m10 * x8 + m16 * x9 + m22 * x10 + m28 * x11 + m34 * x12;
266           x[10] -= m5 * x7 + m11 * x8 + m17 * x9 + m23 * x10 + m29 * x11 + m35 * x12;
267           x[11] -= m6 * x7 + m12 * x8 + m18 * x9 + m24 * x10 + m30 * x11 + m36 * x12;
268 
269           x[12] -= m1 * x13 + m7 * x14 + m13 * x15 + m19 * x16 + m25 * x17 + m31 * x18;
270           x[13] -= m2 * x13 + m8 * x14 + m14 * x15 + m20 * x16 + m26 * x17 + m32 * x18;
271           x[14] -= m3 * x13 + m9 * x14 + m15 * x15 + m21 * x16 + m27 * x17 + m33 * x18;
272           x[15] -= m4 * x13 + m10 * x14 + m16 * x15 + m22 * x16 + m28 * x17 + m34 * x18;
273           x[16] -= m5 * x13 + m11 * x14 + m17 * x15 + m23 * x16 + m29 * x17 + m35 * x18;
274           x[17] -= m6 * x13 + m12 * x14 + m18 * x15 + m24 * x16 + m30 * x17 + m36 * x18;
275 
276           x[18] -= m1 * x19 + m7 * x20 + m13 * x21 + m19 * x22 + m25 * x23 + m31 * x24;
277           x[19] -= m2 * x19 + m8 * x20 + m14 * x21 + m20 * x22 + m26 * x23 + m32 * x24;
278           x[20] -= m3 * x19 + m9 * x20 + m15 * x21 + m21 * x22 + m27 * x23 + m33 * x24;
279           x[21] -= m4 * x19 + m10 * x20 + m16 * x21 + m22 * x22 + m28 * x23 + m34 * x24;
280           x[22] -= m5 * x19 + m11 * x20 + m17 * x21 + m23 * x22 + m29 * x23 + m35 * x24;
281           x[23] -= m6 * x19 + m12 * x20 + m18 * x21 + m24 * x22 + m30 * x23 + m36 * x24;
282 
283           x[24] -= m1 * x25 + m7 * x26 + m13 * x27 + m19 * x28 + m25 * x29 + m31 * x30;
284           x[25] -= m2 * x25 + m8 * x26 + m14 * x27 + m20 * x28 + m26 * x29 + m32 * x30;
285           x[26] -= m3 * x25 + m9 * x26 + m15 * x27 + m21 * x28 + m27 * x29 + m33 * x30;
286           x[27] -= m4 * x25 + m10 * x26 + m16 * x27 + m22 * x28 + m28 * x29 + m34 * x30;
287           x[28] -= m5 * x25 + m11 * x26 + m17 * x27 + m23 * x28 + m29 * x29 + m35 * x30;
288           x[29] -= m6 * x25 + m12 * x26 + m18 * x27 + m24 * x28 + m30 * x29 + m36 * x30;
289 
290           x[30] -= m1 * x31 + m7 * x32 + m13 * x33 + m19 * x34 + m25 * x35 + m31 * x36;
291           x[31] -= m2 * x31 + m8 * x32 + m14 * x33 + m20 * x34 + m26 * x35 + m32 * x36;
292           x[32] -= m3 * x31 + m9 * x32 + m15 * x33 + m21 * x34 + m27 * x35 + m33 * x36;
293           x[33] -= m4 * x31 + m10 * x32 + m16 * x33 + m22 * x34 + m28 * x35 + m34 * x36;
294           x[34] -= m5 * x31 + m11 * x32 + m17 * x33 + m23 * x34 + m29 * x35 + m35 * x36;
295           x[35] -= m6 * x31 + m12 * x32 + m18 * x33 + m24 * x34 + m30 * x35 + m36 * x36;
296 
297           pv += 36;
298         }
299         PetscCall(PetscLogFlops(432.0 * nz + 396.0));
300       }
301       row = *ajtmp++;
302     }
303     /* finished row so stick it into b->a */
304     pv = ba + 36 * bi[i];
305     pj = bj + bi[i];
306     nz = bi[i + 1] - bi[i];
307     for (j = 0; j < nz; j++) {
308       x      = rtmp + 36 * pj[j];
309       pv[0]  = x[0];
310       pv[1]  = x[1];
311       pv[2]  = x[2];
312       pv[3]  = x[3];
313       pv[4]  = x[4];
314       pv[5]  = x[5];
315       pv[6]  = x[6];
316       pv[7]  = x[7];
317       pv[8]  = x[8];
318       pv[9]  = x[9];
319       pv[10] = x[10];
320       pv[11] = x[11];
321       pv[12] = x[12];
322       pv[13] = x[13];
323       pv[14] = x[14];
324       pv[15] = x[15];
325       pv[16] = x[16];
326       pv[17] = x[17];
327       pv[18] = x[18];
328       pv[19] = x[19];
329       pv[20] = x[20];
330       pv[21] = x[21];
331       pv[22] = x[22];
332       pv[23] = x[23];
333       pv[24] = x[24];
334       pv[25] = x[25];
335       pv[26] = x[26];
336       pv[27] = x[27];
337       pv[28] = x[28];
338       pv[29] = x[29];
339       pv[30] = x[30];
340       pv[31] = x[31];
341       pv[32] = x[32];
342       pv[33] = x[33];
343       pv[34] = x[34];
344       pv[35] = x[35];
345       pv += 36;
346     }
347     /* invert diagonal block */
348     w = ba + 36 * diag_offset[i];
349     PetscCall(PetscKernel_A_gets_inverse_A_6(w, shift, allowzeropivot, &zeropivotdetected));
350     if (zeropivotdetected) C->factorerrortype = MAT_FACTOR_NUMERIC_ZEROPIVOT;
351   }
352 
353   PetscCall(PetscFree(rtmp));
354   PetscCall(ISRestoreIndices(isicol, &ic));
355   PetscCall(ISRestoreIndices(isrow, &r));
356 
357   C->ops->solve          = MatSolve_SeqBAIJ_6_inplace;
358   C->ops->solvetranspose = MatSolveTranspose_SeqBAIJ_6_inplace;
359   C->assembled           = PETSC_TRUE;
360 
361   PetscCall(PetscLogFlops(1.333333333333 * 6 * 6 * 6 * b->mbs)); /* from inverting diagonal blocks */
362   PetscFunctionReturn(PETSC_SUCCESS);
363 }
364 
MatLUFactorNumeric_SeqBAIJ_6(Mat B,Mat A,const MatFactorInfo * info)365 PetscErrorCode MatLUFactorNumeric_SeqBAIJ_6(Mat B, Mat A, const MatFactorInfo *info)
366 {
367   Mat             C = B;
368   Mat_SeqBAIJ    *a = (Mat_SeqBAIJ *)A->data, *b = (Mat_SeqBAIJ *)C->data;
369   IS              isrow = b->row, isicol = b->icol;
370   const PetscInt *r, *ic;
371   PetscInt        i, j, k, nz, nzL, row;
372   const PetscInt  n = a->mbs, *ai = a->i, *aj = a->j, *bi = b->i, *bj = b->j;
373   const PetscInt *ajtmp, *bjtmp, *bdiag = b->diag, *pj, bs2 = a->bs2;
374   MatScalar      *rtmp, *pc, *mwork, *v, *pv, *aa = a->a;
375   PetscInt        flg;
376   PetscReal       shift = info->shiftamount;
377   PetscBool       allowzeropivot, zeropivotdetected;
378 
379   PetscFunctionBegin;
380   allowzeropivot = PetscNot(A->erroriffailure);
381   PetscCall(ISGetIndices(isrow, &r));
382   PetscCall(ISGetIndices(isicol, &ic));
383 
384   /* generate work space needed by the factorization */
385   PetscCall(PetscMalloc2(bs2 * n, &rtmp, bs2, &mwork));
386   PetscCall(PetscArrayzero(rtmp, bs2 * n));
387 
388   for (i = 0; i < n; i++) {
389     /* zero rtmp */
390     /* L part */
391     nz    = bi[i + 1] - bi[i];
392     bjtmp = bj + bi[i];
393     for (j = 0; j < nz; j++) PetscCall(PetscArrayzero(rtmp + bs2 * bjtmp[j], bs2));
394 
395     /* U part */
396     nz    = bdiag[i] - bdiag[i + 1];
397     bjtmp = bj + bdiag[i + 1] + 1;
398     for (j = 0; j < nz; j++) PetscCall(PetscArrayzero(rtmp + bs2 * bjtmp[j], bs2));
399 
400     /* load in initial (unfactored row) */
401     nz    = ai[r[i] + 1] - ai[r[i]];
402     ajtmp = aj + ai[r[i]];
403     v     = aa + bs2 * ai[r[i]];
404     for (j = 0; j < nz; j++) PetscCall(PetscArraycpy(rtmp + bs2 * ic[ajtmp[j]], v + bs2 * j, bs2));
405 
406     /* elimination */
407     bjtmp = bj + bi[i];
408     nzL   = bi[i + 1] - bi[i];
409     for (k = 0; k < nzL; k++) {
410       row = bjtmp[k];
411       pc  = rtmp + bs2 * row;
412       for (flg = 0, j = 0; j < bs2; j++) {
413         if (pc[j] != 0.0) {
414           flg = 1;
415           break;
416         }
417       }
418       if (flg) {
419         pv = b->a + bs2 * bdiag[row];
420         /* PetscKernel_A_gets_A_times_B(bs,pc,pv,mwork); *pc = *pc * (*pv); */
421         PetscCall(PetscKernel_A_gets_A_times_B_6(pc, pv, mwork));
422 
423         pj = b->j + bdiag[row + 1] + 1; /* beginning of U(row,:) */
424         pv = b->a + bs2 * (bdiag[row + 1] + 1);
425         nz = bdiag[row] - bdiag[row + 1] - 1; /* num of entries inU(row,:), excluding diag */
426         for (j = 0; j < nz; j++) {
427           /* PetscKernel_A_gets_A_minus_B_times_C(bs,rtmp+bs2*pj[j],pc,pv+bs2*j); */
428           /* rtmp+bs2*pj[j] = rtmp+bs2*pj[j] - (*pc)*(pv+bs2*j) */
429           v = rtmp + bs2 * pj[j];
430           PetscCall(PetscKernel_A_gets_A_minus_B_times_C_6(v, pc, pv));
431           pv += bs2;
432         }
433         PetscCall(PetscLogFlops(432.0 * nz + 396)); /* flops = 2*bs^3*nz + 2*bs^3 - bs2) */
434       }
435     }
436 
437     /* finished row so stick it into b->a */
438     /* L part */
439     pv = b->a + bs2 * bi[i];
440     pj = b->j + bi[i];
441     nz = bi[i + 1] - bi[i];
442     for (j = 0; j < nz; j++) PetscCall(PetscArraycpy(pv + bs2 * j, rtmp + bs2 * pj[j], bs2));
443 
444     /* Mark diagonal and invert diagonal for simpler triangular solves */
445     pv = b->a + bs2 * bdiag[i];
446     pj = b->j + bdiag[i];
447     PetscCall(PetscArraycpy(pv, rtmp + bs2 * pj[0], bs2));
448     PetscCall(PetscKernel_A_gets_inverse_A_6(pv, shift, allowzeropivot, &zeropivotdetected));
449     if (zeropivotdetected) C->factorerrortype = MAT_FACTOR_NUMERIC_ZEROPIVOT;
450 
451     /* U part */
452     pv = b->a + bs2 * (bdiag[i + 1] + 1);
453     pj = b->j + bdiag[i + 1] + 1;
454     nz = bdiag[i] - bdiag[i + 1] - 1;
455     for (j = 0; j < nz; j++) PetscCall(PetscArraycpy(pv + bs2 * j, rtmp + bs2 * pj[j], bs2));
456   }
457 
458   PetscCall(PetscFree2(rtmp, mwork));
459   PetscCall(ISRestoreIndices(isicol, &ic));
460   PetscCall(ISRestoreIndices(isrow, &r));
461 
462   C->ops->solve          = MatSolve_SeqBAIJ_6;
463   C->ops->solvetranspose = MatSolveTranspose_SeqBAIJ_6;
464   C->assembled           = PETSC_TRUE;
465 
466   PetscCall(PetscLogFlops(1.333333333333 * 6 * 6 * 6 * n)); /* from inverting diagonal blocks */
467   PetscFunctionReturn(PETSC_SUCCESS);
468 }
469 
MatILUFactorNumeric_SeqBAIJ_6_NaturalOrdering_inplace(Mat C,Mat A,const MatFactorInfo * info)470 PetscErrorCode MatILUFactorNumeric_SeqBAIJ_6_NaturalOrdering_inplace(Mat C, Mat A, const MatFactorInfo *info)
471 {
472   Mat_SeqBAIJ    *a = (Mat_SeqBAIJ *)A->data, *b = (Mat_SeqBAIJ *)C->data;
473   PetscInt        i, j, n = a->mbs, *bi = b->i, *bj = b->j;
474   PetscInt       *ajtmpold, *ajtmp, nz, row;
475   PetscInt       *ai = a->i, *aj = a->j, *pj;
476   const PetscInt *diag_offset;
477   MatScalar      *pv, *v, *rtmp, *pc, *w, *x;
478   MatScalar       x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13, x14, x15;
479   MatScalar       x16, x17, x18, x19, x20, x21, x22, x23, x24, x25;
480   MatScalar       p1, p2, p3, p4, p5, p6, p7, p8, p9, p10, p11, p12, p13, p14, p15;
481   MatScalar       p16, p17, p18, p19, p20, p21, p22, p23, p24, p25;
482   MatScalar       m1, m2, m3, m4, m5, m6, m7, m8, m9, m10, m11, m12, m13, m14, m15;
483   MatScalar       m16, m17, m18, m19, m20, m21, m22, m23, m24, m25;
484   MatScalar       p26, p27, p28, p29, p30, p31, p32, p33, p34, p35, p36;
485   MatScalar       x26, x27, x28, x29, x30, x31, x32, x33, x34, x35, x36;
486   MatScalar       m26, m27, m28, m29, m30, m31, m32, m33, m34, m35, m36;
487   MatScalar      *ba = b->a, *aa = a->a;
488   PetscReal       shift = info->shiftamount;
489   PetscBool       allowzeropivot, zeropivotdetected;
490 
491   PetscFunctionBegin;
492   /* Since A is C and C is labeled as a factored matrix we need to lie to MatGetDiagonalMarkers_SeqBAIJ() to get it to compute the diagonals */
493   A->factortype = MAT_FACTOR_NONE;
494   PetscCall(MatGetDiagonalMarkers_SeqBAIJ(A, &diag_offset, NULL));
495   A->factortype  = MAT_FACTOR_ILU;
496   allowzeropivot = PetscNot(A->erroriffailure);
497   PetscCall(PetscMalloc1(36 * (n + 1), &rtmp));
498   for (i = 0; i < n; i++) {
499     nz    = bi[i + 1] - bi[i];
500     ajtmp = bj + bi[i];
501     for (j = 0; j < nz; j++) {
502       x    = rtmp + 36 * ajtmp[j];
503       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
504       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
505       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0;
506       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0;
507       x[34] = x[35] = 0.0;
508     }
509     /* load in initial (unfactored row) */
510     nz       = ai[i + 1] - ai[i];
511     ajtmpold = aj + ai[i];
512     v        = aa + 36 * ai[i];
513     for (j = 0; j < nz; j++) {
514       x     = rtmp + 36 * ajtmpold[j];
515       x[0]  = v[0];
516       x[1]  = v[1];
517       x[2]  = v[2];
518       x[3]  = v[3];
519       x[4]  = v[4];
520       x[5]  = v[5];
521       x[6]  = v[6];
522       x[7]  = v[7];
523       x[8]  = v[8];
524       x[9]  = v[9];
525       x[10] = v[10];
526       x[11] = v[11];
527       x[12] = v[12];
528       x[13] = v[13];
529       x[14] = v[14];
530       x[15] = v[15];
531       x[16] = v[16];
532       x[17] = v[17];
533       x[18] = v[18];
534       x[19] = v[19];
535       x[20] = v[20];
536       x[21] = v[21];
537       x[22] = v[22];
538       x[23] = v[23];
539       x[24] = v[24];
540       x[25] = v[25];
541       x[26] = v[26];
542       x[27] = v[27];
543       x[28] = v[28];
544       x[29] = v[29];
545       x[30] = v[30];
546       x[31] = v[31];
547       x[32] = v[32];
548       x[33] = v[33];
549       x[34] = v[34];
550       x[35] = v[35];
551       v += 36;
552     }
553     row = *ajtmp++;
554     while (row < i) {
555       pc  = rtmp + 36 * row;
556       p1  = pc[0];
557       p2  = pc[1];
558       p3  = pc[2];
559       p4  = pc[3];
560       p5  = pc[4];
561       p6  = pc[5];
562       p7  = pc[6];
563       p8  = pc[7];
564       p9  = pc[8];
565       p10 = pc[9];
566       p11 = pc[10];
567       p12 = pc[11];
568       p13 = pc[12];
569       p14 = pc[13];
570       p15 = pc[14];
571       p16 = pc[15];
572       p17 = pc[16];
573       p18 = pc[17];
574       p19 = pc[18];
575       p20 = pc[19];
576       p21 = pc[20];
577       p22 = pc[21];
578       p23 = pc[22];
579       p24 = pc[23];
580       p25 = pc[24];
581       p26 = pc[25];
582       p27 = pc[26];
583       p28 = pc[27];
584       p29 = pc[28];
585       p30 = pc[29];
586       p31 = pc[30];
587       p32 = pc[31];
588       p33 = pc[32];
589       p34 = pc[33];
590       p35 = pc[34];
591       p36 = pc[35];
592       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 || p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 || p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 || p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 || p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 || p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 || p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0) {
593         pv    = ba + 36 * diag_offset[row];
594         pj    = bj + diag_offset[row] + 1;
595         x1    = pv[0];
596         x2    = pv[1];
597         x3    = pv[2];
598         x4    = pv[3];
599         x5    = pv[4];
600         x6    = pv[5];
601         x7    = pv[6];
602         x8    = pv[7];
603         x9    = pv[8];
604         x10   = pv[9];
605         x11   = pv[10];
606         x12   = pv[11];
607         x13   = pv[12];
608         x14   = pv[13];
609         x15   = pv[14];
610         x16   = pv[15];
611         x17   = pv[16];
612         x18   = pv[17];
613         x19   = pv[18];
614         x20   = pv[19];
615         x21   = pv[20];
616         x22   = pv[21];
617         x23   = pv[22];
618         x24   = pv[23];
619         x25   = pv[24];
620         x26   = pv[25];
621         x27   = pv[26];
622         x28   = pv[27];
623         x29   = pv[28];
624         x30   = pv[29];
625         x31   = pv[30];
626         x32   = pv[31];
627         x33   = pv[32];
628         x34   = pv[33];
629         x35   = pv[34];
630         x36   = pv[35];
631         pc[0] = m1 = p1 * x1 + p7 * x2 + p13 * x3 + p19 * x4 + p25 * x5 + p31 * x6;
632         pc[1] = m2 = p2 * x1 + p8 * x2 + p14 * x3 + p20 * x4 + p26 * x5 + p32 * x6;
633         pc[2] = m3 = p3 * x1 + p9 * x2 + p15 * x3 + p21 * x4 + p27 * x5 + p33 * x6;
634         pc[3] = m4 = p4 * x1 + p10 * x2 + p16 * x3 + p22 * x4 + p28 * x5 + p34 * x6;
635         pc[4] = m5 = p5 * x1 + p11 * x2 + p17 * x3 + p23 * x4 + p29 * x5 + p35 * x6;
636         pc[5] = m6 = p6 * x1 + p12 * x2 + p18 * x3 + p24 * x4 + p30 * x5 + p36 * x6;
637 
638         pc[6] = m7 = p1 * x7 + p7 * x8 + p13 * x9 + p19 * x10 + p25 * x11 + p31 * x12;
639         pc[7] = m8 = p2 * x7 + p8 * x8 + p14 * x9 + p20 * x10 + p26 * x11 + p32 * x12;
640         pc[8] = m9 = p3 * x7 + p9 * x8 + p15 * x9 + p21 * x10 + p27 * x11 + p33 * x12;
641         pc[9] = m10 = p4 * x7 + p10 * x8 + p16 * x9 + p22 * x10 + p28 * x11 + p34 * x12;
642         pc[10] = m11 = p5 * x7 + p11 * x8 + p17 * x9 + p23 * x10 + p29 * x11 + p35 * x12;
643         pc[11] = m12 = p6 * x7 + p12 * x8 + p18 * x9 + p24 * x10 + p30 * x11 + p36 * x12;
644 
645         pc[12] = m13 = p1 * x13 + p7 * x14 + p13 * x15 + p19 * x16 + p25 * x17 + p31 * x18;
646         pc[13] = m14 = p2 * x13 + p8 * x14 + p14 * x15 + p20 * x16 + p26 * x17 + p32 * x18;
647         pc[14] = m15 = p3 * x13 + p9 * x14 + p15 * x15 + p21 * x16 + p27 * x17 + p33 * x18;
648         pc[15] = m16 = p4 * x13 + p10 * x14 + p16 * x15 + p22 * x16 + p28 * x17 + p34 * x18;
649         pc[16] = m17 = p5 * x13 + p11 * x14 + p17 * x15 + p23 * x16 + p29 * x17 + p35 * x18;
650         pc[17] = m18 = p6 * x13 + p12 * x14 + p18 * x15 + p24 * x16 + p30 * x17 + p36 * x18;
651 
652         pc[18] = m19 = p1 * x19 + p7 * x20 + p13 * x21 + p19 * x22 + p25 * x23 + p31 * x24;
653         pc[19] = m20 = p2 * x19 + p8 * x20 + p14 * x21 + p20 * x22 + p26 * x23 + p32 * x24;
654         pc[20] = m21 = p3 * x19 + p9 * x20 + p15 * x21 + p21 * x22 + p27 * x23 + p33 * x24;
655         pc[21] = m22 = p4 * x19 + p10 * x20 + p16 * x21 + p22 * x22 + p28 * x23 + p34 * x24;
656         pc[22] = m23 = p5 * x19 + p11 * x20 + p17 * x21 + p23 * x22 + p29 * x23 + p35 * x24;
657         pc[23] = m24 = p6 * x19 + p12 * x20 + p18 * x21 + p24 * x22 + p30 * x23 + p36 * x24;
658 
659         pc[24] = m25 = p1 * x25 + p7 * x26 + p13 * x27 + p19 * x28 + p25 * x29 + p31 * x30;
660         pc[25] = m26 = p2 * x25 + p8 * x26 + p14 * x27 + p20 * x28 + p26 * x29 + p32 * x30;
661         pc[26] = m27 = p3 * x25 + p9 * x26 + p15 * x27 + p21 * x28 + p27 * x29 + p33 * x30;
662         pc[27] = m28 = p4 * x25 + p10 * x26 + p16 * x27 + p22 * x28 + p28 * x29 + p34 * x30;
663         pc[28] = m29 = p5 * x25 + p11 * x26 + p17 * x27 + p23 * x28 + p29 * x29 + p35 * x30;
664         pc[29] = m30 = p6 * x25 + p12 * x26 + p18 * x27 + p24 * x28 + p30 * x29 + p36 * x30;
665 
666         pc[30] = m31 = p1 * x31 + p7 * x32 + p13 * x33 + p19 * x34 + p25 * x35 + p31 * x36;
667         pc[31] = m32 = p2 * x31 + p8 * x32 + p14 * x33 + p20 * x34 + p26 * x35 + p32 * x36;
668         pc[32] = m33 = p3 * x31 + p9 * x32 + p15 * x33 + p21 * x34 + p27 * x35 + p33 * x36;
669         pc[33] = m34 = p4 * x31 + p10 * x32 + p16 * x33 + p22 * x34 + p28 * x35 + p34 * x36;
670         pc[34] = m35 = p5 * x31 + p11 * x32 + p17 * x33 + p23 * x34 + p29 * x35 + p35 * x36;
671         pc[35] = m36 = p6 * x31 + p12 * x32 + p18 * x33 + p24 * x34 + p30 * x35 + p36 * x36;
672 
673         nz = bi[row + 1] - diag_offset[row] - 1;
674         pv += 36;
675         for (j = 0; j < nz; j++) {
676           x1  = pv[0];
677           x2  = pv[1];
678           x3  = pv[2];
679           x4  = pv[3];
680           x5  = pv[4];
681           x6  = pv[5];
682           x7  = pv[6];
683           x8  = pv[7];
684           x9  = pv[8];
685           x10 = pv[9];
686           x11 = pv[10];
687           x12 = pv[11];
688           x13 = pv[12];
689           x14 = pv[13];
690           x15 = pv[14];
691           x16 = pv[15];
692           x17 = pv[16];
693           x18 = pv[17];
694           x19 = pv[18];
695           x20 = pv[19];
696           x21 = pv[20];
697           x22 = pv[21];
698           x23 = pv[22];
699           x24 = pv[23];
700           x25 = pv[24];
701           x26 = pv[25];
702           x27 = pv[26];
703           x28 = pv[27];
704           x29 = pv[28];
705           x30 = pv[29];
706           x31 = pv[30];
707           x32 = pv[31];
708           x33 = pv[32];
709           x34 = pv[33];
710           x35 = pv[34];
711           x36 = pv[35];
712           x   = rtmp + 36 * pj[j];
713           x[0] -= m1 * x1 + m7 * x2 + m13 * x3 + m19 * x4 + m25 * x5 + m31 * x6;
714           x[1] -= m2 * x1 + m8 * x2 + m14 * x3 + m20 * x4 + m26 * x5 + m32 * x6;
715           x[2] -= m3 * x1 + m9 * x2 + m15 * x3 + m21 * x4 + m27 * x5 + m33 * x6;
716           x[3] -= m4 * x1 + m10 * x2 + m16 * x3 + m22 * x4 + m28 * x5 + m34 * x6;
717           x[4] -= m5 * x1 + m11 * x2 + m17 * x3 + m23 * x4 + m29 * x5 + m35 * x6;
718           x[5] -= m6 * x1 + m12 * x2 + m18 * x3 + m24 * x4 + m30 * x5 + m36 * x6;
719 
720           x[6] -= m1 * x7 + m7 * x8 + m13 * x9 + m19 * x10 + m25 * x11 + m31 * x12;
721           x[7] -= m2 * x7 + m8 * x8 + m14 * x9 + m20 * x10 + m26 * x11 + m32 * x12;
722           x[8] -= m3 * x7 + m9 * x8 + m15 * x9 + m21 * x10 + m27 * x11 + m33 * x12;
723           x[9] -= m4 * x7 + m10 * x8 + m16 * x9 + m22 * x10 + m28 * x11 + m34 * x12;
724           x[10] -= m5 * x7 + m11 * x8 + m17 * x9 + m23 * x10 + m29 * x11 + m35 * x12;
725           x[11] -= m6 * x7 + m12 * x8 + m18 * x9 + m24 * x10 + m30 * x11 + m36 * x12;
726 
727           x[12] -= m1 * x13 + m7 * x14 + m13 * x15 + m19 * x16 + m25 * x17 + m31 * x18;
728           x[13] -= m2 * x13 + m8 * x14 + m14 * x15 + m20 * x16 + m26 * x17 + m32 * x18;
729           x[14] -= m3 * x13 + m9 * x14 + m15 * x15 + m21 * x16 + m27 * x17 + m33 * x18;
730           x[15] -= m4 * x13 + m10 * x14 + m16 * x15 + m22 * x16 + m28 * x17 + m34 * x18;
731           x[16] -= m5 * x13 + m11 * x14 + m17 * x15 + m23 * x16 + m29 * x17 + m35 * x18;
732           x[17] -= m6 * x13 + m12 * x14 + m18 * x15 + m24 * x16 + m30 * x17 + m36 * x18;
733 
734           x[18] -= m1 * x19 + m7 * x20 + m13 * x21 + m19 * x22 + m25 * x23 + m31 * x24;
735           x[19] -= m2 * x19 + m8 * x20 + m14 * x21 + m20 * x22 + m26 * x23 + m32 * x24;
736           x[20] -= m3 * x19 + m9 * x20 + m15 * x21 + m21 * x22 + m27 * x23 + m33 * x24;
737           x[21] -= m4 * x19 + m10 * x20 + m16 * x21 + m22 * x22 + m28 * x23 + m34 * x24;
738           x[22] -= m5 * x19 + m11 * x20 + m17 * x21 + m23 * x22 + m29 * x23 + m35 * x24;
739           x[23] -= m6 * x19 + m12 * x20 + m18 * x21 + m24 * x22 + m30 * x23 + m36 * x24;
740 
741           x[24] -= m1 * x25 + m7 * x26 + m13 * x27 + m19 * x28 + m25 * x29 + m31 * x30;
742           x[25] -= m2 * x25 + m8 * x26 + m14 * x27 + m20 * x28 + m26 * x29 + m32 * x30;
743           x[26] -= m3 * x25 + m9 * x26 + m15 * x27 + m21 * x28 + m27 * x29 + m33 * x30;
744           x[27] -= m4 * x25 + m10 * x26 + m16 * x27 + m22 * x28 + m28 * x29 + m34 * x30;
745           x[28] -= m5 * x25 + m11 * x26 + m17 * x27 + m23 * x28 + m29 * x29 + m35 * x30;
746           x[29] -= m6 * x25 + m12 * x26 + m18 * x27 + m24 * x28 + m30 * x29 + m36 * x30;
747 
748           x[30] -= m1 * x31 + m7 * x32 + m13 * x33 + m19 * x34 + m25 * x35 + m31 * x36;
749           x[31] -= m2 * x31 + m8 * x32 + m14 * x33 + m20 * x34 + m26 * x35 + m32 * x36;
750           x[32] -= m3 * x31 + m9 * x32 + m15 * x33 + m21 * x34 + m27 * x35 + m33 * x36;
751           x[33] -= m4 * x31 + m10 * x32 + m16 * x33 + m22 * x34 + m28 * x35 + m34 * x36;
752           x[34] -= m5 * x31 + m11 * x32 + m17 * x33 + m23 * x34 + m29 * x35 + m35 * x36;
753           x[35] -= m6 * x31 + m12 * x32 + m18 * x33 + m24 * x34 + m30 * x35 + m36 * x36;
754 
755           pv += 36;
756         }
757         PetscCall(PetscLogFlops(432.0 * nz + 396.0));
758       }
759       row = *ajtmp++;
760     }
761     /* finished row so stick it into b->a */
762     pv = ba + 36 * bi[i];
763     pj = bj + bi[i];
764     nz = bi[i + 1] - bi[i];
765     for (j = 0; j < nz; j++) {
766       x      = rtmp + 36 * pj[j];
767       pv[0]  = x[0];
768       pv[1]  = x[1];
769       pv[2]  = x[2];
770       pv[3]  = x[3];
771       pv[4]  = x[4];
772       pv[5]  = x[5];
773       pv[6]  = x[6];
774       pv[7]  = x[7];
775       pv[8]  = x[8];
776       pv[9]  = x[9];
777       pv[10] = x[10];
778       pv[11] = x[11];
779       pv[12] = x[12];
780       pv[13] = x[13];
781       pv[14] = x[14];
782       pv[15] = x[15];
783       pv[16] = x[16];
784       pv[17] = x[17];
785       pv[18] = x[18];
786       pv[19] = x[19];
787       pv[20] = x[20];
788       pv[21] = x[21];
789       pv[22] = x[22];
790       pv[23] = x[23];
791       pv[24] = x[24];
792       pv[25] = x[25];
793       pv[26] = x[26];
794       pv[27] = x[27];
795       pv[28] = x[28];
796       pv[29] = x[29];
797       pv[30] = x[30];
798       pv[31] = x[31];
799       pv[32] = x[32];
800       pv[33] = x[33];
801       pv[34] = x[34];
802       pv[35] = x[35];
803       pv += 36;
804     }
805     /* invert diagonal block */
806     w = ba + 36 * diag_offset[i];
807     PetscCall(PetscKernel_A_gets_inverse_A_6(w, shift, allowzeropivot, &zeropivotdetected));
808     if (zeropivotdetected) C->factorerrortype = MAT_FACTOR_NUMERIC_ZEROPIVOT;
809   }
810 
811   PetscCall(PetscFree(rtmp));
812 
813   C->ops->solve          = MatSolve_SeqBAIJ_6_NaturalOrdering_inplace;
814   C->ops->solvetranspose = MatSolveTranspose_SeqBAIJ_6_NaturalOrdering_inplace;
815   C->assembled           = PETSC_TRUE;
816 
817   PetscCall(PetscLogFlops(1.333333333333 * 6 * 6 * 6 * b->mbs)); /* from inverting diagonal blocks */
818   PetscFunctionReturn(PETSC_SUCCESS);
819 }
820 
MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering(Mat B,Mat A,const MatFactorInfo * info)821 PetscErrorCode MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering(Mat B, Mat A, const MatFactorInfo *info)
822 {
823   Mat             C = B;
824   Mat_SeqBAIJ    *a = (Mat_SeqBAIJ *)A->data, *b = (Mat_SeqBAIJ *)C->data;
825   PetscInt        i, j, k, nz, nzL, row;
826   const PetscInt  n = a->mbs, *ai = a->i, *aj = a->j, *bi = b->i, *bj = b->j;
827   const PetscInt *ajtmp, *bjtmp, *bdiag = b->diag, *pj, bs2 = a->bs2;
828   MatScalar      *rtmp, *pc, *mwork, *v, *pv, *aa = a->a;
829   PetscInt        flg;
830   PetscReal       shift = info->shiftamount;
831   PetscBool       allowzeropivot, zeropivotdetected;
832 
833   PetscFunctionBegin;
834   allowzeropivot = PetscNot(A->erroriffailure);
835 
836   /* generate work space needed by the factorization */
837   PetscCall(PetscMalloc2(bs2 * n, &rtmp, bs2, &mwork));
838   PetscCall(PetscArrayzero(rtmp, bs2 * n));
839 
840   for (i = 0; i < n; i++) {
841     /* zero rtmp */
842     /* L part */
843     nz    = bi[i + 1] - bi[i];
844     bjtmp = bj + bi[i];
845     for (j = 0; j < nz; j++) PetscCall(PetscArrayzero(rtmp + bs2 * bjtmp[j], bs2));
846 
847     /* U part */
848     nz    = bdiag[i] - bdiag[i + 1];
849     bjtmp = bj + bdiag[i + 1] + 1;
850     for (j = 0; j < nz; j++) PetscCall(PetscArrayzero(rtmp + bs2 * bjtmp[j], bs2));
851 
852     /* load in initial (unfactored row) */
853     nz    = ai[i + 1] - ai[i];
854     ajtmp = aj + ai[i];
855     v     = aa + bs2 * ai[i];
856     for (j = 0; j < nz; j++) PetscCall(PetscArraycpy(rtmp + bs2 * ajtmp[j], v + bs2 * j, bs2));
857 
858     /* elimination */
859     bjtmp = bj + bi[i];
860     nzL   = bi[i + 1] - bi[i];
861     for (k = 0; k < nzL; k++) {
862       row = bjtmp[k];
863       pc  = rtmp + bs2 * row;
864       for (flg = 0, j = 0; j < bs2; j++) {
865         if (pc[j] != 0.0) {
866           flg = 1;
867           break;
868         }
869       }
870       if (flg) {
871         pv = b->a + bs2 * bdiag[row];
872         /* PetscKernel_A_gets_A_times_B(bs,pc,pv,mwork); *pc = *pc * (*pv); */
873         PetscCall(PetscKernel_A_gets_A_times_B_6(pc, pv, mwork));
874 
875         pj = b->j + bdiag[row + 1] + 1; /* beginning of U(row,:) */
876         pv = b->a + bs2 * (bdiag[row + 1] + 1);
877         nz = bdiag[row] - bdiag[row + 1] - 1; /* num of entries inU(row,:), excluding diag */
878         for (j = 0; j < nz; j++) {
879           /* PetscKernel_A_gets_A_minus_B_times_C(bs,rtmp+bs2*pj[j],pc,pv+bs2*j); */
880           /* rtmp+bs2*pj[j] = rtmp+bs2*pj[j] - (*pc)*(pv+bs2*j) */
881           v = rtmp + bs2 * pj[j];
882           PetscCall(PetscKernel_A_gets_A_minus_B_times_C_6(v, pc, pv));
883           pv += bs2;
884         }
885         PetscCall(PetscLogFlops(432.0 * nz + 396)); /* flops = 2*bs^3*nz + 2*bs^3 - bs2) */
886       }
887     }
888 
889     /* finished row so stick it into b->a */
890     /* L part */
891     pv = b->a + bs2 * bi[i];
892     pj = b->j + bi[i];
893     nz = bi[i + 1] - bi[i];
894     for (j = 0; j < nz; j++) PetscCall(PetscArraycpy(pv + bs2 * j, rtmp + bs2 * pj[j], bs2));
895 
896     /* Mark diagonal and invert diagonal for simpler triangular solves */
897     pv = b->a + bs2 * bdiag[i];
898     pj = b->j + bdiag[i];
899     PetscCall(PetscArraycpy(pv, rtmp + bs2 * pj[0], bs2));
900     PetscCall(PetscKernel_A_gets_inverse_A_6(pv, shift, allowzeropivot, &zeropivotdetected));
901     if (zeropivotdetected) C->factorerrortype = MAT_FACTOR_NUMERIC_ZEROPIVOT;
902 
903     /* U part */
904     pv = b->a + bs2 * (bdiag[i + 1] + 1);
905     pj = b->j + bdiag[i + 1] + 1;
906     nz = bdiag[i] - bdiag[i + 1] - 1;
907     for (j = 0; j < nz; j++) PetscCall(PetscArraycpy(pv + bs2 * j, rtmp + bs2 * pj[j], bs2));
908   }
909   PetscCall(PetscFree2(rtmp, mwork));
910 
911   C->ops->solve          = MatSolve_SeqBAIJ_6_NaturalOrdering;
912   C->ops->solvetranspose = MatSolveTranspose_SeqBAIJ_6_NaturalOrdering;
913   C->assembled           = PETSC_TRUE;
914 
915   PetscCall(PetscLogFlops(1.333333333333 * 6 * 6 * 6 * n)); /* from inverting diagonal blocks */
916   PetscFunctionReturn(PETSC_SUCCESS);
917 }
918