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 bool
lower_cl_images_to_tex_impl(nir_function_impl * impl)28 lower_cl_images_to_tex_impl(nir_function_impl *impl)
29 {
30    bool progress = false;
31 
32    nir_builder b;
33    nir_builder_init(&b, impl);
34 
35    nir_foreach_block(block, impl) {
36       nir_foreach_instr_safe(instr, block) {
37          if (instr->type != nir_instr_type_intrinsic)
38             continue;
39 
40          nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
41 
42          unsigned num_srcs;
43          nir_texop texop;
44          switch (intrin->intrinsic) {
45          case nir_intrinsic_image_deref_load:
46             texop = nir_texop_txf;
47             num_srcs = 3;
48             break;
49          case nir_intrinsic_image_deref_size:
50             texop = nir_texop_txs;
51             num_srcs = 2;
52             break;
53          default:
54             /* Not an op we can lower */
55             continue;
56          }
57 
58          /* In CL 1.2, images are required to be either read-only or
59           * write-only.  We can always translate the read-only image ops to
60           * texture ops.  In CL 2.0 (and an extension), the ability is added
61           * to have read-write images but sampling (with a sampler) is only
62           * allowed on read-only images.  As long as we only lower read-only
63           * images to texture ops, everything should stay consistent.
64           */
65          if (!(nir_intrinsic_access(intrin) & ACCESS_NON_WRITEABLE))
66             continue;
67 
68          nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]);
69 
70          b.cursor = nir_instr_remove(&intrin->instr);
71 
72          nir_tex_instr *tex = nir_tex_instr_create(b.shader, num_srcs);
73          tex->op = texop;
74 
75          tex->sampler_dim = glsl_get_sampler_dim(deref->type);
76          tex->is_array = glsl_sampler_type_is_array(deref->type);
77          tex->is_shadow = false;
78 
79          unsigned coord_components =
80             glsl_get_sampler_dim_coordinate_components(tex->sampler_dim);
81          if (glsl_sampler_type_is_array(deref->type))
82             tex->coord_components++;
83 
84          tex->src[0].src_type = nir_tex_src_texture_deref;
85          tex->src[0].src = nir_src_for_ssa(&deref->dest.ssa);
86 
87          switch (intrin->intrinsic) {
88          case nir_intrinsic_image_deref_load: {
89             assert(intrin->src[1].is_ssa);
90             tex->coord_components = coord_components;
91             nir_ssa_def *coord =
92                nir_channels(&b, intrin->src[1].ssa,
93                             (1 << tex->coord_components) - 1);
94             tex->src[1].src_type = nir_tex_src_coord;
95             tex->src[1].src = nir_src_for_ssa(coord);
96 
97             assert(intrin->src[3].is_ssa);
98             nir_ssa_def *lod = intrin->src[3].ssa;
99             tex->src[2].src_type = nir_tex_src_lod;
100             tex->src[2].src = nir_src_for_ssa(lod);
101 
102             assert(num_srcs == 3);
103 
104             tex->dest_type = nir_intrinsic_dest_type(intrin);
105             nir_ssa_dest_init(&tex->instr, &tex->dest, 4, 32, NULL);
106             break;
107          }
108 
109          case nir_intrinsic_image_deref_size: {
110             assert(intrin->src[1].is_ssa);
111             nir_ssa_def *lod = intrin->src[1].ssa;
112             tex->src[1].src_type = nir_tex_src_lod;
113             tex->src[1].src = nir_src_for_ssa(lod);
114 
115             assert(num_srcs == 2);
116 
117             tex->dest_type = nir_type_uint32;
118             nir_ssa_dest_init(&tex->instr, &tex->dest,
119                               coord_components, 32, NULL);
120             break;
121          }
122 
123          default:
124             unreachable("Unsupported intrinsic");
125          }
126 
127          nir_builder_instr_insert(&b, &tex->instr);
128 
129          nir_ssa_def *res = &tex->dest.ssa;
130          if (res->num_components != intrin->dest.ssa.num_components) {
131             unsigned num_components = intrin->dest.ssa.num_components;
132             res = nir_channels(&b, res, (1 << num_components) - 1);
133          }
134 
135          nir_ssa_def_rewrite_uses(&intrin->dest.ssa, nir_src_for_ssa(res));
136          progress = true;
137       }
138    }
139 
140    if (progress) {
141       nir_metadata_preserve(impl, nir_metadata_block_index |
142                                   nir_metadata_dominance);
143    } else {
144       nir_metadata_preserve(impl, nir_metadata_all);
145    }
146 
147    return progress;
148 }
149 
150 /** Lowers OpenCL image ops to texture ops for read-only images */
151 bool
nir_lower_cl_images_to_tex(nir_shader * shader)152 nir_lower_cl_images_to_tex(nir_shader *shader)
153 {
154    bool progress = false;
155 
156    nir_foreach_function(function, shader) {
157       if (function->impl && lower_cl_images_to_tex_impl(function->impl))
158          progress = true;
159    }
160 
161    return progress;
162 }
163