1 /*
2 * Copyright © 2020 Google LLC
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 * @file
26 *
27 * Removes unused trailing components from store data.
28 *
29 */
30
31 #include "nir.h"
32 #include "nir_builder.h"
33
34 static bool
opt_shrink_vectors_image_store(nir_builder * b,nir_intrinsic_instr * instr)35 opt_shrink_vectors_image_store(nir_builder *b, nir_intrinsic_instr *instr)
36 {
37 enum pipe_format format;
38 if (instr->intrinsic == nir_intrinsic_image_deref_store) {
39 nir_deref_instr *deref = nir_src_as_deref(instr->src[0]);
40 format = nir_deref_instr_get_variable(deref)->data.image.format;
41 } else {
42 format = nir_intrinsic_format(instr);
43 }
44 if (format == PIPE_FORMAT_NONE)
45 return false;
46
47 unsigned components = util_format_get_nr_components(format);
48 if (components >= instr->num_components)
49 return false;
50
51 nir_def *data = nir_trim_vector(b, instr->src[3].ssa, components);
52 nir_src_rewrite(&instr->src[3], data);
53 instr->num_components = components;
54
55 return true;
56 }
57
58 static bool
opt_shrink_store_instr(nir_builder * b,nir_intrinsic_instr * instr,bool shrink_image_store)59 opt_shrink_store_instr(nir_builder *b, nir_intrinsic_instr *instr, bool shrink_image_store)
60 {
61 b->cursor = nir_before_instr(&instr->instr);
62
63 switch (instr->intrinsic) {
64 case nir_intrinsic_store_output:
65 case nir_intrinsic_store_per_vertex_output:
66 case nir_intrinsic_store_per_view_output:
67 case nir_intrinsic_store_ssbo:
68 case nir_intrinsic_store_shared:
69 case nir_intrinsic_store_global:
70 case nir_intrinsic_store_scratch:
71 break;
72 case nir_intrinsic_bindless_image_store:
73 case nir_intrinsic_image_deref_store:
74 case nir_intrinsic_image_store:
75 return shrink_image_store && opt_shrink_vectors_image_store(b, instr);
76 default:
77 return false;
78 }
79
80 /* Must be a vectorized intrinsic that we can resize. */
81 assert(instr->num_components != 0);
82
83 /* Trim the num_components stored according to the write mask. */
84 unsigned write_mask = nir_intrinsic_write_mask(instr);
85 unsigned last_bit = util_last_bit(write_mask);
86 if (last_bit < instr->num_components) {
87 nir_def *def = nir_trim_vector(b, instr->src[0].ssa, last_bit);
88 nir_src_rewrite(&instr->src[0], def);
89 instr->num_components = last_bit;
90
91 return true;
92 }
93
94 return false;
95 }
96
97 bool
nir_opt_shrink_stores(nir_shader * shader,bool shrink_image_store)98 nir_opt_shrink_stores(nir_shader *shader, bool shrink_image_store)
99 {
100 bool progress = false;
101
102 nir_foreach_function_impl(impl, shader) {
103 nir_builder b = nir_builder_create(impl);
104
105 nir_foreach_block(block, impl) {
106 nir_foreach_instr(instr, block) {
107 if (instr->type != nir_instr_type_intrinsic)
108 continue;
109 nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
110 progress |= opt_shrink_store_instr(&b, intrin, shrink_image_store);
111 }
112 }
113
114 if (progress) {
115 nir_metadata_preserve(impl,
116 nir_metadata_control_flow);
117 } else {
118 nir_metadata_preserve(impl, nir_metadata_all);
119 }
120 }
121
122 return progress;
123 }
124