1 /*
2 * Copyright © 2014 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 * Authors:
24 * Connor Abbott (cwabbott0@gmail.com)
25 *
26 */
27
28 #include "nir.h"
29 #include "nir_builder.h"
30
31 static bool
convert_block(nir_block * block,nir_builder * b)32 convert_block(nir_block *block, nir_builder *b)
33 {
34 bool progress = false;
35
36 nir_foreach_instr_safe(instr, block) {
37 if (instr->type != nir_instr_type_intrinsic)
38 continue;
39
40 nir_intrinsic_instr *load_var = nir_instr_as_intrinsic(instr);
41
42 if (load_var->intrinsic != nir_intrinsic_load_var)
43 continue;
44
45 nir_variable *var = load_var->variables[0]->var;
46 if (var->data.mode != nir_var_system_value)
47 continue;
48
49 b->cursor = nir_after_instr(&load_var->instr);
50
51 nir_ssa_def *sysval = NULL;
52 switch (var->data.location) {
53 case SYSTEM_VALUE_GLOBAL_INVOCATION_ID: {
54 /* From the GLSL man page for gl_GlobalInvocationID:
55 *
56 * "The value of gl_GlobalInvocationID is equal to
57 * gl_WorkGroupID * gl_WorkGroupSize + gl_LocalInvocationID"
58 */
59
60 nir_const_value local_size;
61 memset(&local_size, 0, sizeof(local_size));
62 local_size.u32[0] = b->shader->info.cs.local_size[0];
63 local_size.u32[1] = b->shader->info.cs.local_size[1];
64 local_size.u32[2] = b->shader->info.cs.local_size[2];
65
66 nir_ssa_def *group_id = nir_load_work_group_id(b);
67 nir_ssa_def *local_id = nir_load_local_invocation_id(b);
68
69 sysval = nir_iadd(b, nir_imul(b, group_id,
70 nir_build_imm(b, 3, 32, local_size)),
71 local_id);
72 break;
73 }
74
75 case SYSTEM_VALUE_LOCAL_INVOCATION_INDEX: {
76 /* If lower_cs_local_index_from_id is true, then we derive the local
77 * index from the local id.
78 */
79 if (!b->shader->options->lower_cs_local_index_from_id)
80 break;
81
82 /* From the GLSL man page for gl_LocalInvocationIndex:
83 *
84 * "The value of gl_LocalInvocationIndex is equal to
85 * gl_LocalInvocationID.z * gl_WorkGroupSize.x *
86 * gl_WorkGroupSize.y + gl_LocalInvocationID.y *
87 * gl_WorkGroupSize.x + gl_LocalInvocationID.x"
88 */
89 nir_ssa_def *local_id = nir_load_local_invocation_id(b);
90
91 nir_ssa_def *size_x =
92 nir_imm_int(b, b->shader->info.cs.local_size[0]);
93 nir_ssa_def *size_y =
94 nir_imm_int(b, b->shader->info.cs.local_size[1]);
95
96 sysval = nir_imul(b, nir_channel(b, local_id, 2),
97 nir_imul(b, size_x, size_y));
98 sysval = nir_iadd(b, sysval,
99 nir_imul(b, nir_channel(b, local_id, 1), size_x));
100 sysval = nir_iadd(b, sysval, nir_channel(b, local_id, 0));
101 break;
102 }
103
104 case SYSTEM_VALUE_VERTEX_ID:
105 if (b->shader->options->vertex_id_zero_based) {
106 sysval = nir_iadd(b,
107 nir_load_vertex_id_zero_base(b),
108 nir_load_base_vertex(b));
109 } else {
110 sysval = nir_load_vertex_id(b);
111 }
112 break;
113
114 case SYSTEM_VALUE_INSTANCE_INDEX:
115 sysval = nir_iadd(b,
116 nir_load_instance_id(b),
117 nir_load_base_instance(b));
118 break;
119
120 case SYSTEM_VALUE_SUBGROUP_EQ_MASK:
121 case SYSTEM_VALUE_SUBGROUP_GE_MASK:
122 case SYSTEM_VALUE_SUBGROUP_GT_MASK:
123 case SYSTEM_VALUE_SUBGROUP_LE_MASK:
124 case SYSTEM_VALUE_SUBGROUP_LT_MASK: {
125 nir_intrinsic_op op =
126 nir_intrinsic_from_system_value(var->data.location);
127 nir_intrinsic_instr *load = nir_intrinsic_instr_create(b->shader, op);
128 nir_ssa_dest_init_for_type(&load->instr, &load->dest,
129 var->type, NULL);
130 load->num_components = load->dest.ssa.num_components;
131 nir_builder_instr_insert(b, &load->instr);
132 sysval = &load->dest.ssa;
133 break;
134 }
135
136 default:
137 break;
138 }
139
140 if (sysval == NULL) {
141 nir_intrinsic_op sysval_op =
142 nir_intrinsic_from_system_value(var->data.location);
143 sysval = nir_load_system_value(b, sysval_op, 0);
144 }
145
146 nir_ssa_def_rewrite_uses(&load_var->dest.ssa, nir_src_for_ssa(sysval));
147 nir_instr_remove(&load_var->instr);
148
149 progress = true;
150 }
151
152 return progress;
153 }
154
155 static bool
convert_impl(nir_function_impl * impl)156 convert_impl(nir_function_impl *impl)
157 {
158 bool progress = false;
159 nir_builder builder;
160 nir_builder_init(&builder, impl);
161
162 nir_foreach_block(block, impl) {
163 progress |= convert_block(block, &builder);
164 }
165
166 nir_metadata_preserve(impl, nir_metadata_block_index |
167 nir_metadata_dominance);
168 return progress;
169 }
170
171 bool
nir_lower_system_values(nir_shader * shader)172 nir_lower_system_values(nir_shader *shader)
173 {
174 bool progress = false;
175
176 nir_foreach_function(function, shader) {
177 if (function->impl)
178 progress = convert_impl(function->impl) || progress;
179 }
180
181 exec_list_make_empty(&shader->system_values);
182
183 return progress;
184 }
185