1 /*
2 * Copyright © 2021 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 */
23
24 /**
25 * This lowering pass supports (as configured via nir_lower_image_options)
26 * image related conversions:
27 * + cube array size lowering. The size operation is converted from cube
28 * size to a 2d-array with the z component divided by 6.
29 */
30
31 #include "nir.h"
32 #include "nir_builder.h"
33
34 static void
lower_cube_size(nir_builder * b,nir_intrinsic_instr * intrin)35 lower_cube_size(nir_builder *b, nir_intrinsic_instr *intrin)
36 {
37 assert(nir_intrinsic_image_dim(intrin) == GLSL_SAMPLER_DIM_CUBE);
38
39 b->cursor = nir_before_instr(&intrin->instr);
40
41 nir_intrinsic_instr *_2darray_size =
42 nir_instr_as_intrinsic(nir_instr_clone(b->shader, &intrin->instr));
43 nir_intrinsic_set_image_dim(_2darray_size, GLSL_SAMPLER_DIM_2D);
44 nir_intrinsic_set_image_array(_2darray_size, true);
45 nir_builder_instr_insert(b, &_2darray_size->instr);
46
47 nir_ssa_def *size = nir_instr_ssa_def(&_2darray_size->instr);
48 nir_ssa_def *comps[NIR_MAX_VEC_COMPONENTS] = { NULL, };
49 unsigned coord_comps = intrin->dest.ssa.num_components;
50 for (unsigned c = 0; c < coord_comps; c++) {
51 if (c == 2) {
52 comps[2] = nir_idiv(b, nir_channel(b, size, 2), nir_imm_int(b, 6));
53 } else {
54 comps[c] = nir_channel(b, size, c);
55 }
56 }
57
58 nir_ssa_def *vec = nir_vec(b, comps, intrin->dest.ssa.num_components);
59 nir_ssa_def_rewrite_uses(&intrin->dest.ssa, vec);
60 nir_instr_remove(&intrin->instr);
61 nir_instr_free(&intrin->instr);
62 }
63
64 static bool
lower_image_instr(nir_builder * b,nir_instr * instr,void * state)65 lower_image_instr(nir_builder *b, nir_instr *instr, void *state)
66 {
67 if (instr->type != nir_instr_type_intrinsic)
68 return false;
69
70 const nir_lower_image_options *options = state;
71 nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
72
73 switch (intrin->intrinsic) {
74 case nir_intrinsic_image_size:
75 case nir_intrinsic_image_deref_size:
76 case nir_intrinsic_bindless_image_size:
77 if (options->lower_cube_size &&
78 nir_intrinsic_image_dim(intrin) == GLSL_SAMPLER_DIM_CUBE) {
79 lower_cube_size(b, intrin);
80 return true;
81 }
82 return false;
83
84 default:
85 return false;
86 }
87 }
88
89 bool
nir_lower_image(nir_shader * nir,const nir_lower_image_options * options)90 nir_lower_image(nir_shader *nir, const nir_lower_image_options *options)
91 {
92 return nir_shader_instructions_pass(nir, lower_image_instr,
93 nir_metadata_block_index |
94 nir_metadata_dominance, (void*)options);
95 }
96