2 * Copyright (C) 2005-2007 Brian Paul All Rights Reserved.
3 * Copyright (C) 2008 VMware, Inc. All Rights Reserved.
4 * Copyright © 2014 Intel Corporation
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:
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
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.
26 #include "compiler/nir/nir.h"
27 #include "compiler/nir/nir_builder.h"
29 #include "ir_uniform.h"
31 #include "main/compiler.h"
32 #include "main/mtypes.h"
35 lower_tex_src_to_offset(nir_builder
*b
,
36 nir_tex_instr
*instr
, unsigned src_idx
)
38 nir_ssa_def
*index
= NULL
;
39 unsigned base_index
= 0;
40 unsigned array_elements
= 1;
41 nir_tex_src
*src
= &instr
->src
[src_idx
];
42 bool is_sampler
= src
->src_type
== nir_tex_src_sampler_deref
;
44 /* We compute first the offsets */
45 nir_deref_instr
*deref
= nir_instr_as_deref(src
->src
.ssa
->parent_instr
);
46 while (deref
->deref_type
!= nir_deref_type_var
) {
47 assert(deref
->parent
.is_ssa
);
48 nir_deref_instr
*parent
=
49 nir_instr_as_deref(deref
->parent
.ssa
->parent_instr
);
51 assert(deref
->deref_type
== nir_deref_type_array
);
53 if (nir_src_is_const(deref
->arr
.index
) && index
== NULL
) {
54 /* We're still building a direct index */
55 base_index
+= nir_src_as_uint(deref
->arr
.index
) * array_elements
;
58 /* We used to be direct but not anymore */
59 index
= nir_imm_int(b
, base_index
);
63 index
= nir_iadd(b
, index
,
64 nir_imul(b
, nir_imm_int(b
, array_elements
),
65 nir_ssa_for_src(b
, deref
->arr
.index
, 1)));
68 array_elements
*= glsl_get_length(parent
->type
);
74 index
= nir_umin(b
, index
, nir_imm_int(b
, array_elements
- 1));
76 /* We hit the deref_var. This is the end of the line */
77 assert(deref
->deref_type
== nir_deref_type_var
);
79 base_index
+= deref
->var
->data
.binding
;
81 /* We have the offsets, we apply them, rewriting the source or removing
85 nir_instr_rewrite_src(&instr
->instr
, &src
->src
,
86 nir_src_for_ssa(index
));
88 src
->src_type
= is_sampler
?
89 nir_tex_src_sampler_offset
:
90 nir_tex_src_texture_offset
;
92 instr
->texture_array_size
= array_elements
;
94 nir_tex_instr_remove_src(instr
, src_idx
);
98 instr
->sampler_index
= base_index
;
100 instr
->texture_index
= base_index
;
101 instr
->texture_array_size
= array_elements
;
106 lower_sampler(nir_builder
*b
, nir_tex_instr
*instr
)
109 nir_tex_instr_src_index(instr
, nir_tex_src_texture_deref
);
111 if (texture_idx
>= 0) {
112 b
->cursor
= nir_before_instr(&instr
->instr
);
114 lower_tex_src_to_offset(b
, instr
, texture_idx
);
118 nir_tex_instr_src_index(instr
, nir_tex_src_sampler_deref
);
120 if (sampler_idx
>= 0) {
121 lower_tex_src_to_offset(b
, instr
, sampler_idx
);
124 if (texture_idx
< 0 && sampler_idx
< 0)
131 lower_impl(nir_function_impl
*impl
)
134 nir_builder_init(&b
, impl
);
135 bool progress
= false;
137 nir_foreach_block(block
, impl
) {
138 nir_foreach_instr(instr
, block
) {
139 if (instr
->type
== nir_instr_type_tex
)
140 progress
|= lower_sampler(&b
, nir_instr_as_tex(instr
));
148 gl_nir_lower_samplers(nir_shader
*shader
,
149 const struct gl_shader_program
*shader_program
)
151 bool progress
= false;
153 /* First, use gl_nir_lower_samplers_as_derefs to set var->data.binding
154 * based on the uniforms, and split structures to simplify derefs.
156 gl_nir_lower_samplers_as_deref(shader
, shader_program
);
158 /* Next, lower derefs to offsets. */
159 nir_foreach_function(function
, shader
) {
161 progress
|= lower_impl(function
->impl
);