1 // Copyright (c) 2017-2026, Lawrence Livermore National Security, LLC and other CEED contributors.
2 // All Rights Reserved. See the top-level LICENSE and NOTICE files for details.
3 //
4 // SPDX-License-Identifier: BSD-2-Clause
5 //
6 // This file is part of CEED: http://github.com/ceed
7 #pragma once
8
9 #include <ceed/types.h>
10 #include "ex-common.h"
11
12 /// libCEED Q-function for building quadrature data for a diffusion operator
build_diff(void * ctx,const CeedInt Q,const CeedScalar * const * in,CeedScalar * const * out)13 CEED_QFUNCTION(build_diff)(void *ctx, const CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
14 // in[0] is Jacobians with shape [dim, dim, Q]
15 // in[1] is quadrature weights, size (Q)
16 const CeedScalar *w = in[1];
17 CeedScalar(*q_data)[CEED_Q_VLA] = (CeedScalar(*)[CEED_Q_VLA])out[0];
18 struct BuildContext *build_data = (struct BuildContext *)ctx;
19
20 // At every quadrature point, compute w/det(J).adj(J).adj(J)^T and store
21 // the symmetric part of the result.
22 switch (build_data->dim + 10 * build_data->space_dim) {
23 case 11: {
24 const CeedScalar(*J)[1][CEED_Q_VLA] = (const CeedScalar(*)[1][CEED_Q_VLA])in[0];
25
26 CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) { q_data[0][i] = w[i] / J[0][0][i]; } // End of Quadrature Point Loop
27 } break;
28 case 22: {
29 const CeedScalar(*J)[2][CEED_Q_VLA] = (const CeedScalar(*)[2][CEED_Q_VLA])in[0];
30
31 CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
32 // J: 0 2 q_data: 0 2 adj(J): J11 -J01
33 // 1 3 2 1 -J10 J00
34 const CeedScalar J00 = J[0][0][i];
35 const CeedScalar J10 = J[0][1][i];
36 const CeedScalar J01 = J[1][0][i];
37 const CeedScalar J11 = J[1][1][i];
38 const CeedScalar qw = w[i] / (J00 * J11 - J10 * J01);
39
40 q_data[0][i] = qw * (J01 * J01 + J11 * J11);
41 q_data[1][i] = qw * (J00 * J00 + J10 * J10);
42 q_data[2][i] = -qw * (J00 * J01 + J10 * J11);
43 } // End of Quadrature Point Loop
44 } break;
45 case 33: {
46 const CeedScalar(*J)[3][CEED_Q_VLA] = (const CeedScalar(*)[3][CEED_Q_VLA])in[0];
47
48 CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
49 // Compute the adjoint
50 CeedScalar A[3][3];
51
52 for (CeedInt j = 0; j < 3; j++) {
53 for (CeedInt k = 0; k < 3; k++) {
54 // Equivalent code with J as a VLA and no mod operations:
55 // A[k][j] = J[j+1][k+1]*J[j+2][k+2] - J[j+1][k+2]*J[j+2][k+1]
56 A[k][j] =
57 J[(k + 1) % 3][(j + 1) % 3][i] * J[(k + 2) % 3][(j + 2) % 3][i] - J[(k + 2) % 3][(j + 1) % 3][i] * J[(k + 1) % 3][(j + 2) % 3][i];
58 }
59 }
60
61 // Compute quadrature weight / det(J)
62 const CeedScalar qw = w[i] / (J[0][0][i] * A[0][0] + J[0][1][i] * A[0][1] + J[0][2][i] * A[0][2]);
63
64 // Compute geometric factors
65 // Stored in Voigt convention
66 // 0 5 4
67 // 5 1 3
68 // 4 3 2
69 q_data[0][i] = qw * (A[0][0] * A[0][0] + A[0][1] * A[0][1] + A[0][2] * A[0][2]);
70 q_data[1][i] = qw * (A[1][0] * A[1][0] + A[1][1] * A[1][1] + A[1][2] * A[1][2]);
71 q_data[2][i] = qw * (A[2][0] * A[2][0] + A[2][1] * A[2][1] + A[2][2] * A[2][2]);
72 q_data[3][i] = qw * (A[1][0] * A[2][0] + A[1][1] * A[2][1] + A[1][2] * A[2][2]);
73 q_data[4][i] = qw * (A[0][0] * A[2][0] + A[0][1] * A[2][1] + A[0][2] * A[2][2]);
74 q_data[5][i] = qw * (A[0][0] * A[1][0] + A[0][1] * A[1][1] + A[0][2] * A[1][2]);
75 } // End of Quadrature Point Loop
76 } break;
77 }
78 return CEED_ERROR_SUCCESS;
79 }
80
81 /// libCEED Q-function for applying a diff operator
apply_diff(void * ctx,const CeedInt Q,const CeedScalar * const * in,CeedScalar * const * out)82 CEED_QFUNCTION(apply_diff)(void *ctx, const CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
83 struct BuildContext *build_data = (struct BuildContext *)ctx;
84 // in[0], out[0] solution gradients with shape [dim, 1, Q]
85 // in[1] is quadrature data with shape [num_components, Q]
86 const CeedScalar(*q_data)[CEED_Q_VLA] = (const CeedScalar(*)[CEED_Q_VLA])in[1];
87
88 switch (build_data->dim) {
89 case 1: {
90 const CeedScalar *ug = in[0];
91 CeedScalar *vg = out[0];
92
93 CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) { vg[i] = ug[i] * q_data[0][i]; } // End of Quadrature Point Loop
94 } break;
95 case 2: {
96 const CeedScalar(*ug)[CEED_Q_VLA] = (const CeedScalar(*)[CEED_Q_VLA])in[0];
97 CeedScalar(*vg)[CEED_Q_VLA] = (CeedScalar(*)[CEED_Q_VLA])out[0];
98
99 CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
100 // Read q_data (dXdxdXdx_T symmetric matrix)
101 // Stored in Voigt convention
102 // 0 2
103 // 2 1
104 const CeedScalar dXdxdXdx_T[2][2] = {
105 {q_data[0][i], q_data[2][i]},
106 {q_data[2][i], q_data[1][i]}
107 };
108
109 // j = direction of vg
110 for (int j = 0; j < 2; j++) vg[j][i] = (ug[0][i] * dXdxdXdx_T[0][j] + ug[1][i] * dXdxdXdx_T[1][j]);
111 } // End of Quadrature Point Loop
112 } break;
113 case 3: {
114 const CeedScalar(*ug)[CEED_Q_VLA] = (const CeedScalar(*)[CEED_Q_VLA])in[0];
115 CeedScalar(*vg)[CEED_Q_VLA] = (CeedScalar(*)[CEED_Q_VLA])out[0];
116
117 CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
118 // Read q_data (dXdxdXdx_T symmetric matrix)
119 // Stored in Voigt convention
120 // 0 5 4
121 // 5 1 3
122 // 4 3 2
123 const CeedScalar dXdxdXdx_T[3][3] = {
124 {q_data[0][i], q_data[5][i], q_data[4][i]},
125 {q_data[5][i], q_data[1][i], q_data[3][i]},
126 {q_data[4][i], q_data[3][i], q_data[2][i]}
127 };
128
129 // j = direction of vg
130 for (int j = 0; j < 3; j++) vg[j][i] = (ug[0][i] * dXdxdXdx_T[0][j] + ug[1][i] * dXdxdXdx_T[1][j] + ug[2][i] * dXdxdXdx_T[2][j]);
131 } // End of Quadrature Point Loop
132 } break;
133 }
134 return CEED_ERROR_SUCCESS;
135 }
136