1 /*
2  * Copyright © 2015 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 
25 #include "nir.h"
26 #include "nir_builder.h"
27 
28 /*
29  * lowers:
30  *
31  * packDouble2x32(foo) -> packDouble2x32Split(foo.x, foo.y)
32  * unpackDouble2x32(foo) -> vec2(unpackDouble2x32_x(foo), unpackDouble2x32_y(foo))
33  * packInt2x32(foo) -> packInt2x32Split(foo.x, foo.y)
34  * unpackInt2x32(foo) -> vec2(unpackInt2x32_x(foo), unpackInt2x32_y(foo))
35  */
36 
37 static nir_ssa_def *
lower_pack_64_from_32(nir_builder * b,nir_ssa_def * src)38 lower_pack_64_from_32(nir_builder *b, nir_ssa_def *src)
39 {
40    return nir_pack_64_2x32_split(b, nir_channel(b, src, 0),
41                                     nir_channel(b, src, 1));
42 }
43 
44 static nir_ssa_def *
lower_unpack_64_to_32(nir_builder * b,nir_ssa_def * src)45 lower_unpack_64_to_32(nir_builder *b, nir_ssa_def *src)
46 {
47    return nir_vec2(b, nir_unpack_64_2x32_split_x(b, src),
48                       nir_unpack_64_2x32_split_y(b, src));
49 }
50 
51 static nir_ssa_def *
lower_pack_32_from_16(nir_builder * b,nir_ssa_def * src)52 lower_pack_32_from_16(nir_builder *b, nir_ssa_def *src)
53 {
54    return nir_pack_32_2x16_split(b, nir_channel(b, src, 0),
55                                     nir_channel(b, src, 1));
56 }
57 
58 static nir_ssa_def *
lower_unpack_32_to_16(nir_builder * b,nir_ssa_def * src)59 lower_unpack_32_to_16(nir_builder *b, nir_ssa_def *src)
60 {
61    return nir_vec2(b, nir_unpack_32_2x16_split_x(b, src),
62                       nir_unpack_32_2x16_split_y(b, src));
63 }
64 
65 static nir_ssa_def *
lower_pack_64_from_16(nir_builder * b,nir_ssa_def * src)66 lower_pack_64_from_16(nir_builder *b, nir_ssa_def *src)
67 {
68    nir_ssa_def *xy = nir_pack_32_2x16_split(b, nir_channel(b, src, 0),
69                                                nir_channel(b, src, 1));
70 
71    nir_ssa_def *zw = nir_pack_32_2x16_split(b, nir_channel(b, src, 2),
72                                                nir_channel(b, src, 3));
73 
74    return nir_pack_64_2x32_split(b, xy, zw);
75 }
76 
77 static nir_ssa_def *
lower_unpack_64_to_16(nir_builder * b,nir_ssa_def * src)78 lower_unpack_64_to_16(nir_builder *b, nir_ssa_def *src)
79 {
80    nir_ssa_def *xy = nir_unpack_64_2x32_split_x(b, src);
81    nir_ssa_def *zw = nir_unpack_64_2x32_split_y(b, src);
82 
83    return nir_vec4(b, nir_unpack_32_2x16_split_x(b, xy),
84                       nir_unpack_32_2x16_split_y(b, xy),
85                       nir_unpack_32_2x16_split_x(b, zw),
86                       nir_unpack_32_2x16_split_y(b, zw));
87 }
88 
89 static nir_ssa_def *
lower_pack_32_from_8(nir_builder * b,nir_ssa_def * src)90 lower_pack_32_from_8(nir_builder *b, nir_ssa_def *src)
91 {
92    return nir_pack_32_4x8_split(b, nir_channel(b, src, 0),
93                                    nir_channel(b, src, 1),
94                                    nir_channel(b, src, 2),
95                                    nir_channel(b, src, 3));
96 }
97 
98 static bool
lower_pack_instr(nir_builder * b,nir_instr * instr,void * data)99 lower_pack_instr(nir_builder *b, nir_instr *instr, void *data)
100 {
101    if (instr->type != nir_instr_type_alu)
102       return false;
103 
104    nir_alu_instr *alu_instr = (nir_alu_instr *) instr;
105 
106    if (alu_instr->op != nir_op_pack_64_2x32 &&
107        alu_instr->op != nir_op_unpack_64_2x32 &&
108        alu_instr->op != nir_op_pack_64_4x16 &&
109        alu_instr->op != nir_op_unpack_64_4x16 &&
110        alu_instr->op != nir_op_pack_32_2x16 &&
111        alu_instr->op != nir_op_unpack_32_2x16 &&
112        alu_instr->op != nir_op_pack_32_4x8)
113       return false;
114 
115    b->cursor = nir_before_instr(&alu_instr->instr);
116 
117    nir_ssa_def *src = nir_ssa_for_alu_src(b, alu_instr, 0);
118    nir_ssa_def *dest;
119 
120    switch (alu_instr->op) {
121    case nir_op_pack_64_2x32:
122       dest = lower_pack_64_from_32(b, src);
123       break;
124    case nir_op_unpack_64_2x32:
125       dest = lower_unpack_64_to_32(b, src);
126       break;
127    case nir_op_pack_64_4x16:
128       dest = lower_pack_64_from_16(b, src);
129       break;
130    case nir_op_unpack_64_4x16:
131       dest = lower_unpack_64_to_16(b, src);
132       break;
133    case nir_op_pack_32_2x16:
134       dest = lower_pack_32_from_16(b, src);
135       break;
136    case nir_op_unpack_32_2x16:
137       dest = lower_unpack_32_to_16(b, src);
138       break;
139    case nir_op_pack_32_4x8:
140       dest = lower_pack_32_from_8(b, src);
141       break;
142    default:
143       unreachable("Impossible opcode");
144    }
145    nir_ssa_def_rewrite_uses(&alu_instr->dest.dest.ssa, dest);
146    nir_instr_remove(&alu_instr->instr);
147 
148    return true;
149 }
150 
151 bool
nir_lower_pack(nir_shader * shader)152 nir_lower_pack(nir_shader *shader)
153 {
154    return nir_shader_instructions_pass(shader, lower_pack_instr,
155          nir_metadata_block_index | nir_metadata_dominance, NULL);
156 }
157