1 /*
2 * Copyright © 2016 Broadcom
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 #include "nir.h"
25 #include "nir_builder.h"
26
27 /** @file nir_lower_io_to_scalar.c
28 *
29 * Replaces nir_load_input/nir_store_output operations with num_components !=
30 * 1 with individual per-channel operations.
31 */
32
33 static void
lower_load_input_to_scalar(nir_builder * b,nir_intrinsic_instr * intr)34 lower_load_input_to_scalar(nir_builder *b, nir_intrinsic_instr *intr)
35 {
36 b->cursor = nir_before_instr(&intr->instr);
37
38 assert(intr->dest.is_ssa);
39
40 nir_ssa_def *loads[4];
41
42 for (unsigned i = 0; i < intr->num_components; i++) {
43 nir_intrinsic_instr *chan_intr =
44 nir_intrinsic_instr_create(b->shader, intr->intrinsic);
45 nir_ssa_dest_init(&chan_intr->instr, &chan_intr->dest,
46 1, intr->dest.ssa.bit_size, NULL);
47 chan_intr->num_components = 1;
48
49 nir_intrinsic_set_base(chan_intr, nir_intrinsic_base(intr));
50 nir_intrinsic_set_component(chan_intr, nir_intrinsic_component(intr) + i);
51 /* offset */
52 chan_intr->src[0] = intr->src[0];
53
54 nir_builder_instr_insert(b, &chan_intr->instr);
55
56 loads[i] = &chan_intr->dest.ssa;
57 }
58
59 nir_ssa_def_rewrite_uses(&intr->dest.ssa,
60 nir_src_for_ssa(nir_vec(b, loads,
61 intr->num_components)));
62 nir_instr_remove(&intr->instr);
63 }
64
65 static void
lower_store_output_to_scalar(nir_builder * b,nir_intrinsic_instr * intr)66 lower_store_output_to_scalar(nir_builder *b, nir_intrinsic_instr *intr)
67 {
68 b->cursor = nir_before_instr(&intr->instr);
69
70 nir_ssa_def *value = nir_ssa_for_src(b, intr->src[0], intr->num_components);
71
72 for (unsigned i = 0; i < intr->num_components; i++) {
73 if (!(nir_intrinsic_write_mask(intr) & (1 << i)))
74 continue;
75
76 nir_intrinsic_instr *chan_intr =
77 nir_intrinsic_instr_create(b->shader, intr->intrinsic);
78 chan_intr->num_components = 1;
79
80 nir_intrinsic_set_base(chan_intr, nir_intrinsic_base(intr));
81 nir_intrinsic_set_write_mask(chan_intr, 0x1);
82 nir_intrinsic_set_component(chan_intr, nir_intrinsic_component(intr) + i);
83
84 /* value */
85 chan_intr->src[0] = nir_src_for_ssa(nir_channel(b, value, i));
86 /* offset */
87 chan_intr->src[1] = intr->src[1];
88
89 nir_builder_instr_insert(b, &chan_intr->instr);
90 }
91
92 nir_instr_remove(&intr->instr);
93 }
94
95 void
nir_lower_io_to_scalar(nir_shader * shader,nir_variable_mode mask)96 nir_lower_io_to_scalar(nir_shader *shader, nir_variable_mode mask)
97 {
98 nir_foreach_function(function, shader) {
99 if (function->impl) {
100 nir_builder b;
101 nir_builder_init(&b, function->impl);
102
103 nir_foreach_block(block, function->impl) {
104 nir_foreach_instr_safe(instr, block) {
105 if (instr->type != nir_instr_type_intrinsic)
106 continue;
107
108 nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
109
110 if (intr->num_components == 1)
111 continue;
112
113 switch (intr->intrinsic) {
114 case nir_intrinsic_load_input:
115 if (mask & nir_var_shader_in)
116 lower_load_input_to_scalar(&b, intr);
117 break;
118 case nir_intrinsic_store_output:
119 if (mask & nir_var_shader_out)
120 lower_store_output_to_scalar(&b, intr);
121 break;
122 default:
123 break;
124 }
125 }
126 }
127 }
128 }
129 }
130