1 /*
2 * Copyright (C) 2020 Google, Inc.
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 FROM,
20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21 * SOFTWARE.
22 */
23
24 #include "nir.h"
25 #include "nir_builder.h"
26
27 /* Lower mediump outputs to float16, int16, or uint16. */
28
29 void
nir_lower_mediump_outputs(nir_shader * nir)30 nir_lower_mediump_outputs(nir_shader *nir)
31 {
32 nir_function_impl *impl = nir_shader_get_entrypoint(nir);
33 assert(impl);
34
35 /* Get rid of old derefs before we change the types of the variables */
36 nir_opt_dce(nir);
37
38 nir_builder b;
39 nir_builder_init(&b, impl);
40
41 nir_foreach_block_safe (block, impl) {
42 nir_foreach_instr_safe (instr, block) {
43 if (instr->type != nir_instr_type_intrinsic)
44 continue;
45
46 nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
47 if (intr->intrinsic != nir_intrinsic_store_output)
48 continue;
49
50 if (!nir_intrinsic_io_semantics(intr).medium_precision)
51 break; /* can't lower */
52
53 switch (nir_intrinsic_src_type(intr)) {
54 case nir_type_float32:
55 b.cursor = nir_before_instr(&intr->instr);
56 nir_instr_rewrite_src(&intr->instr, &intr->src[0],
57 nir_src_for_ssa(nir_f2f16(&b, intr->src[0].ssa)));
58 nir_intrinsic_set_src_type(intr, nir_type_float16);
59 break;
60
61 case nir_type_int32:
62 b.cursor = nir_before_instr(&intr->instr);
63 nir_instr_rewrite_src(&intr->instr, &intr->src[0],
64 nir_src_for_ssa(nir_i2i16(&b, intr->src[0].ssa)));
65 nir_intrinsic_set_src_type(intr, nir_type_int16);
66 break;
67
68 case nir_type_uint32:
69 b.cursor = nir_before_instr(&intr->instr);
70 nir_instr_rewrite_src(&intr->instr, &intr->src[0],
71 nir_src_for_ssa(nir_u2u16(&b, intr->src[0].ssa)));
72 nir_intrinsic_set_src_type(intr, nir_type_uint16);
73 break;
74
75 default:;
76 }
77 }
78 }
79 }
80