1 /*
2 * Copyright © 2016 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
24 #include "nir.h"
25 #include "nir_builder.h"
26 #include "lvp_lower_vulkan_resource.h"
27
28 static nir_ssa_def *
load_frag_coord(nir_builder * b)29 load_frag_coord(nir_builder *b)
30 {
31 nir_variable *pos =
32 nir_find_variable_with_location(b->shader, nir_var_shader_in,
33 VARYING_SLOT_POS);
34 if (pos == NULL) {
35 pos = nir_variable_create(b->shader, nir_var_shader_in,
36 glsl_vec4_type(), NULL);
37 pos->data.location = VARYING_SLOT_POS;
38 }
39 /**
40 * From Vulkan spec:
41 * "The OriginLowerLeft execution mode must not be used; fragment entry
42 * points must declare OriginUpperLeft."
43 *
44 * So at this point origin_upper_left should be true
45 */
46 assert(b->shader->info.fs.origin_upper_left == true);
47
48 return nir_load_var(b, pos);
49 }
50
51 static bool
try_lower_input_load(nir_function_impl * impl,nir_intrinsic_instr * load,bool use_fragcoord_sysval)52 try_lower_input_load(nir_function_impl *impl, nir_intrinsic_instr *load,
53 bool use_fragcoord_sysval)
54 {
55 nir_deref_instr *deref = nir_src_as_deref(load->src[0]);
56 assert(glsl_type_is_image(deref->type));
57
58 enum glsl_sampler_dim image_dim = glsl_get_sampler_dim(deref->type);
59 if (image_dim != GLSL_SAMPLER_DIM_SUBPASS &&
60 image_dim != GLSL_SAMPLER_DIM_SUBPASS_MS)
61 return false;
62
63 nir_builder b;
64 nir_builder_init(&b, impl);
65 b.cursor = nir_before_instr(&load->instr);
66
67 nir_ssa_def *frag_coord = use_fragcoord_sysval ? nir_load_frag_coord(&b)
68 : load_frag_coord(&b);
69 frag_coord = nir_f2i32(&b, frag_coord);
70 nir_ssa_def *offset = nir_ssa_for_src(&b, load->src[1], 2);
71 nir_ssa_def *pos = nir_iadd(&b, frag_coord, offset);
72
73 nir_ssa_def *layer = nir_load_view_index(&b);
74 nir_ssa_def *coord =
75 nir_vec4(&b, nir_channel(&b, pos, 0), nir_channel(&b, pos, 1), layer, nir_imm_int(&b, 0));
76
77 nir_instr_rewrite_src(&load->instr, &load->src[1], nir_src_for_ssa(coord));
78
79 return true;
80 }
81
82 bool
lvp_lower_input_attachments(nir_shader * shader,bool use_fragcoord_sysval)83 lvp_lower_input_attachments(nir_shader *shader, bool use_fragcoord_sysval)
84 {
85 assert(shader->info.stage == MESA_SHADER_FRAGMENT);
86 bool progress = false;
87
88 nir_foreach_function(function, shader) {
89 if (!function->impl)
90 continue;
91
92 nir_foreach_block(block, function->impl) {
93 nir_foreach_instr_safe(instr, block) {
94 if (instr->type != nir_instr_type_intrinsic)
95 continue;
96
97 nir_intrinsic_instr *load = nir_instr_as_intrinsic(instr);
98
99 if (load->intrinsic != nir_intrinsic_image_deref_load)
100 continue;
101
102 progress |= try_lower_input_load(function->impl, load,
103 use_fragcoord_sysval);
104 }
105 }
106 }
107
108 return progress;
109 }
110