1 /*
2 * Copyright © 2020 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
27 static const struct glsl_type *
get_sampler_type_for_image(const struct glsl_type * type)28 get_sampler_type_for_image(const struct glsl_type *type)
29 {
30 if (glsl_type_is_array(type)) {
31 const struct glsl_type *elem_type =
32 get_sampler_type_for_image(glsl_get_array_element(type));
33 return glsl_array_type(elem_type, glsl_get_length(type), 0 /*explicit size*/);
34 }
35
36 assert((glsl_type_is_image(type)));
37 return glsl_sampler_type(glsl_get_sampler_dim(type), false,
38 glsl_sampler_type_is_array(type),
39 glsl_get_sampler_result_type(type));
40 }
41
42 static void
replace_image_type_with_sampler(nir_deref_instr * deref)43 replace_image_type_with_sampler(nir_deref_instr *deref)
44 {
45 const struct glsl_type *type = deref->type;
46
47 /* If we've already chased up the deref chain this far from a different intrinsic, we're done */
48 if (glsl_type_is_sampler(glsl_without_array(type)))
49 return;
50
51 deref->type = get_sampler_type_for_image(type);
52 if (deref->deref_type == nir_deref_type_var) {
53 type = deref->var->type;
54 if (!glsl_type_is_sampler(glsl_without_array(type))) {
55 deref->var->type = get_sampler_type_for_image(type);
56 memset(&deref->var->data.sampler, 0, sizeof(deref->var->data.sampler));
57 }
58 } else {
59 nir_deref_instr *parent = nir_deref_instr_parent(deref);
60 if (parent)
61 replace_image_type_with_sampler(parent);
62 }
63 }
64
65 struct readonly_image_lower_options {
66 bool per_variable;
67 };
68
69 static bool
is_readonly_image_op(const nir_instr * instr,const void * context)70 is_readonly_image_op(const nir_instr *instr, const void *context)
71 {
72 struct readonly_image_lower_options *options = (struct readonly_image_lower_options *)context;
73 if (instr->type != nir_instr_type_intrinsic)
74 return false;
75 nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
76 if (intrin->intrinsic != nir_intrinsic_image_deref_load &&
77 intrin->intrinsic != nir_intrinsic_image_deref_size)
78 return false;
79
80 nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]);
81 nir_variable *var = nir_deref_instr_get_variable(deref);
82
83 /* In CL 1.2, images are required to be either read-only or
84 * write-only. We can always translate the read-only image ops to
85 * texture ops. In CL 2.0 (and an extension), the ability is added
86 * to have read-write images but sampling (with a sampler) is only
87 * allowed on read-only images. As long as we only lower read-only
88 * images to texture ops, everything should stay consistent.
89 */
90 enum gl_access_qualifier access = 0;
91 if (options->per_variable) {
92 if (var)
93 access = var->data.access;
94 } else
95 access = nir_intrinsic_access(intrin);
96 if (access & ACCESS_NON_WRITEABLE)
97 return true;
98
99 return false;
100 }
101
102 static nir_ssa_def *
lower_readonly_image_op(nir_builder * b,nir_instr * instr,void * context)103 lower_readonly_image_op(nir_builder *b, nir_instr *instr, void *context)
104 {
105 struct readonly_image_lower_options *options = (struct readonly_image_lower_options *)context;
106 nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
107 unsigned num_srcs;
108 nir_texop texop;
109 switch (intrin->intrinsic) {
110 case nir_intrinsic_image_deref_load:
111 texop = nir_texop_txf;
112 num_srcs = 3;
113 break;
114 case nir_intrinsic_image_deref_size:
115 texop = nir_texop_txs;
116 num_srcs = 2;
117 break;
118 default:
119 unreachable("Filtered above");
120 }
121
122 nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]);
123
124 nir_tex_instr *tex = nir_tex_instr_create(b->shader, num_srcs);
125 tex->op = texop;
126
127 tex->sampler_dim = glsl_get_sampler_dim(deref->type);
128 tex->is_array = glsl_sampler_type_is_array(deref->type);
129 tex->is_shadow = false;
130
131 unsigned coord_components =
132 glsl_get_sampler_dim_coordinate_components(tex->sampler_dim);
133 if (glsl_sampler_type_is_array(deref->type))
134 coord_components++;
135
136 tex->src[0].src_type = nir_tex_src_texture_deref;
137 tex->src[0].src = nir_src_for_ssa(&deref->dest.ssa);
138
139 if (options->per_variable) {
140 assert(nir_deref_instr_get_variable(deref));
141 replace_image_type_with_sampler(deref);
142 }
143
144 tex->coord_components = coord_components;
145 switch (intrin->intrinsic) {
146 case nir_intrinsic_image_deref_load: {
147 assert(intrin->src[1].is_ssa);
148 nir_ssa_def *coord =
149 nir_channels(b, intrin->src[1].ssa,
150 (1 << tex->coord_components) - 1);
151 tex->src[1].src_type = nir_tex_src_coord;
152 tex->src[1].src = nir_src_for_ssa(coord);
153
154 assert(intrin->src[3].is_ssa);
155 nir_ssa_def *lod = intrin->src[3].ssa;
156 tex->src[2].src_type = nir_tex_src_lod;
157 tex->src[2].src = nir_src_for_ssa(lod);
158
159 assert(num_srcs == 3);
160
161 tex->dest_type = nir_intrinsic_dest_type(intrin);
162 nir_ssa_dest_init(&tex->instr, &tex->dest, 4, 32, NULL);
163 break;
164 }
165
166 case nir_intrinsic_image_deref_size: {
167 assert(intrin->src[1].is_ssa);
168 nir_ssa_def *lod = intrin->src[1].ssa;
169 tex->src[1].src_type = nir_tex_src_lod;
170 tex->src[1].src = nir_src_for_ssa(lod);
171
172 assert(num_srcs == 2);
173
174 tex->dest_type = nir_type_uint32;
175 nir_ssa_dest_init(&tex->instr, &tex->dest,
176 coord_components, 32, NULL);
177 break;
178 }
179
180 default:
181 unreachable("Unsupported intrinsic");
182 }
183
184 nir_builder_instr_insert(b, &tex->instr);
185
186 nir_ssa_def *res = &tex->dest.ssa;
187 if (res->num_components != intrin->dest.ssa.num_components) {
188 unsigned num_components = intrin->dest.ssa.num_components;
189 res = nir_channels(b, res, (1 << num_components) - 1);
190 }
191
192 return res;
193 }
194
195 /** Lowers image ops to texture ops for read-only images
196 *
197 * If per_variable is set:
198 * - Variable access is used to indicate read-only instead of intrinsic access
199 * - Variable/deref types will be changed from image types to sampler types
200 *
201 * per_variable should not be set for OpenCL, because all image types will be void-returning,
202 * and there is no corresponding valid sampler type, and it will collide with the "bare" sampler type.
203 */
204 bool
nir_lower_readonly_images_to_tex(nir_shader * shader,bool per_variable)205 nir_lower_readonly_images_to_tex(nir_shader *shader, bool per_variable)
206 {
207 assert(shader->info.stage != MESA_SHADER_KERNEL || !per_variable);
208
209 struct readonly_image_lower_options options = { per_variable };
210 return nir_shader_lower_instructions(shader,
211 is_readonly_image_op,
212 lower_readonly_image_op,
213 &options);
214 }
215