1 /*
2 * Copyright (C) 2005-2007 Brian Paul All Rights Reserved.
3 * Copyright (C) 2008 VMware, Inc. All Rights Reserved.
4 * Copyright © 2014 Intel Corporation
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice (including the next
14 * paragraph) shall be included in all copies or substantial portions of the
15 * Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
22 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
23 * DEALINGS IN THE SOFTWARE.
24 */
25
26 #include "nir.h"
27 #include "nir_builder.h"
28 #include "compiler/glsl/ir_uniform.h"
29
30 #include "main/compiler.h"
31 #include "main/mtypes.h"
32 #include "program/prog_parameter.h"
33 #include "program/program.h"
34
35 /* Calculate the sampler index based on array indicies and also
36 * calculate the base uniform location for struct members.
37 */
38 static void
calc_sampler_offsets(nir_deref * tail,nir_tex_instr * instr,unsigned * array_elements,nir_ssa_def ** indirect,nir_builder * b,unsigned * location)39 calc_sampler_offsets(nir_deref *tail, nir_tex_instr *instr,
40 unsigned *array_elements, nir_ssa_def **indirect,
41 nir_builder *b, unsigned *location)
42 {
43 if (tail->child == NULL)
44 return;
45
46 switch (tail->child->deref_type) {
47 case nir_deref_type_array: {
48 nir_deref_array *deref_array = nir_deref_as_array(tail->child);
49
50 assert(deref_array->deref_array_type != nir_deref_array_type_wildcard);
51
52 calc_sampler_offsets(tail->child, instr, array_elements,
53 indirect, b, location);
54 instr->texture_index += deref_array->base_offset * *array_elements;
55
56 if (deref_array->deref_array_type == nir_deref_array_type_indirect) {
57 nir_ssa_def *mul =
58 nir_imul(b, nir_imm_int(b, *array_elements),
59 nir_ssa_for_src(b, deref_array->indirect, 1));
60
61 nir_instr_rewrite_src(&instr->instr, &deref_array->indirect,
62 NIR_SRC_INIT);
63
64 if (*indirect) {
65 *indirect = nir_iadd(b, *indirect, mul);
66 } else {
67 *indirect = mul;
68 }
69 }
70
71 *array_elements *= glsl_get_length(tail->type);
72 break;
73 }
74
75 case nir_deref_type_struct: {
76 nir_deref_struct *deref_struct = nir_deref_as_struct(tail->child);
77 *location += glsl_get_record_location_offset(tail->type, deref_struct->index);
78 calc_sampler_offsets(tail->child, instr, array_elements,
79 indirect, b, location);
80 break;
81 }
82
83 default:
84 unreachable("Invalid deref type");
85 break;
86 }
87 }
88
89 static void
lower_sampler(nir_tex_instr * instr,const struct gl_shader_program * shader_program,gl_shader_stage stage,nir_builder * b)90 lower_sampler(nir_tex_instr *instr, const struct gl_shader_program *shader_program,
91 gl_shader_stage stage, nir_builder *b)
92 {
93 if (instr->texture == NULL)
94 return;
95
96 /* In GLSL, we only fill out the texture field. The sampler is inferred */
97 assert(instr->sampler == NULL);
98
99 instr->texture_index = 0;
100 unsigned location = instr->texture->var->data.location;
101 unsigned array_elements = 1;
102 nir_ssa_def *indirect = NULL;
103
104 b->cursor = nir_before_instr(&instr->instr);
105 calc_sampler_offsets(&instr->texture->deref, instr, &array_elements,
106 &indirect, b, &location);
107
108 if (indirect) {
109 assert(array_elements >= 1);
110 indirect = nir_umin(b, indirect, nir_imm_int(b, array_elements - 1));
111
112 /* First, we have to resize the array of texture sources */
113 nir_tex_src *new_srcs = rzalloc_array(instr, nir_tex_src,
114 instr->num_srcs + 2);
115
116 for (unsigned i = 0; i < instr->num_srcs; i++) {
117 new_srcs[i].src_type = instr->src[i].src_type;
118 nir_instr_move_src(&instr->instr, &new_srcs[i].src,
119 &instr->src[i].src);
120 }
121
122 ralloc_free(instr->src);
123 instr->src = new_srcs;
124
125 /* Now we can go ahead and move the source over to being a
126 * first-class texture source.
127 */
128 instr->src[instr->num_srcs].src_type = nir_tex_src_texture_offset;
129 instr->num_srcs++;
130 nir_instr_rewrite_src(&instr->instr,
131 &instr->src[instr->num_srcs - 1].src,
132 nir_src_for_ssa(indirect));
133
134 instr->src[instr->num_srcs].src_type = nir_tex_src_sampler_offset;
135 instr->num_srcs++;
136 nir_instr_rewrite_src(&instr->instr,
137 &instr->src[instr->num_srcs - 1].src,
138 nir_src_for_ssa(indirect));
139
140 instr->texture_array_size = array_elements;
141 }
142
143 if (location > shader_program->data->NumUniformStorage - 1 ||
144 !shader_program->data->UniformStorage[location].opaque[stage].active) {
145 assert(!"cannot return a sampler");
146 return;
147 }
148
149 instr->texture_index +=
150 shader_program->data->UniformStorage[location].opaque[stage].index;
151
152 instr->sampler_index = instr->texture_index;
153
154 instr->texture = NULL;
155 }
156
157 static void
lower_impl(nir_function_impl * impl,const struct gl_shader_program * shader_program,gl_shader_stage stage)158 lower_impl(nir_function_impl *impl, const struct gl_shader_program *shader_program,
159 gl_shader_stage stage)
160 {
161 nir_builder b;
162 nir_builder_init(&b, impl);
163
164 nir_foreach_block(block, impl) {
165 nir_foreach_instr(instr, block) {
166 if (instr->type == nir_instr_type_tex)
167 lower_sampler(nir_instr_as_tex(instr), shader_program, stage, &b);
168 }
169 }
170 }
171
172 void
nir_lower_samplers(nir_shader * shader,const struct gl_shader_program * shader_program)173 nir_lower_samplers(nir_shader *shader,
174 const struct gl_shader_program *shader_program)
175 {
176 nir_foreach_function(function, shader) {
177 if (function->impl)
178 lower_impl(function->impl, shader_program, shader->stage);
179 }
180 }
181