1 /*
2 * Copyright © 2014 Intel Corporation
3 * Copyright © 2023 Igalia S.L.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice (including the next
13 * paragraph) shall be included in all copies or substantial portions of the
14 * Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22 * IN THE SOFTWARE.
23 */
24
25 #include "etnaviv_nir.h"
26 #include "etnaviv_compiler_nir.h"
27
28 /*
29 * This pass lowers the neg and abs operations to pass_flags on
30 * ALU operations.
31 */
32
33 static void
alu_src_consume_abs(nir_instr * instr,unsigned idx)34 alu_src_consume_abs(nir_instr *instr, unsigned idx)
35 {
36 set_src_mod_abs(instr, idx);
37 }
38
39 static void
alu_src_consume_negate(nir_instr * instr,unsigned idx)40 alu_src_consume_negate(nir_instr *instr, unsigned idx)
41 {
42 /* If abs is set on the source, the negate goes away */
43 if (!is_src_mod_abs(instr, idx))
44 toggle_src_mod_neg(instr, idx);
45 }
46
47 static bool
nir_lower_to_source_mods_instr(nir_builder * b,nir_instr * instr,void * data)48 nir_lower_to_source_mods_instr(nir_builder *b, nir_instr *instr,
49 void *data)
50 {
51 bool progress = false;
52
53 if (instr->type != nir_instr_type_alu)
54 return false;
55
56 nir_alu_instr *alu = nir_instr_as_alu(instr);
57
58 for (unsigned i = 0; i < nir_op_infos[alu->op].num_inputs; i++) {
59 if (alu->src[i].src.ssa->parent_instr->type != nir_instr_type_alu)
60 continue;
61
62 nir_alu_instr *parent = nir_instr_as_alu(alu->src[i].src.ssa->parent_instr);
63
64 if (nir_alu_type_get_base_type(nir_op_infos[alu->op].input_types[i]) != nir_type_float)
65 continue;
66
67 if (!(parent->op == nir_op_fabs) &&
68 !(parent->op == nir_op_fneg)) {
69 continue;
70 }
71
72 if (nir_src_bit_size(alu->src[i].src) == 64)
73 continue;
74
75 /* We can only store up to 3 source modifiers. */
76 if (i >= 3)
77 continue;
78
79 nir_src_rewrite(&alu->src[i].src, parent->src[0].src.ssa);
80
81 /* Apply any modifiers that come from the parent opcode */
82 if (parent->op == nir_op_fneg)
83 alu_src_consume_negate(instr, i);
84 if (parent->op == nir_op_fabs)
85 alu_src_consume_abs(instr, i);
86
87 /* Apply modifiers from the parent source */
88 if (is_src_mod_neg(&parent->instr, 0))
89 alu_src_consume_negate(instr, i);
90 if (is_src_mod_abs(&parent->instr, 0))
91 alu_src_consume_abs(instr, i);
92
93 for (int j = 0; j < 4; ++j) {
94 if (!nir_alu_instr_channel_used(alu, i, j))
95 continue;
96 alu->src[i].swizzle[j] = parent->src[0].swizzle[alu->src[i].swizzle[j]];
97 }
98
99 if (nir_def_is_unused(&parent->def))
100 nir_instr_remove(&parent->instr);
101
102 progress = true;
103 }
104
105 return progress;
106 }
107
108 bool
etna_nir_lower_to_source_mods(nir_shader * shader)109 etna_nir_lower_to_source_mods(nir_shader *shader)
110 {
111 nir_shader_clear_pass_flags(shader);
112
113 return nir_shader_instructions_pass(shader,
114 nir_lower_to_source_mods_instr,
115 nir_metadata_control_flow,
116 NULL);
117 }
118