1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
|
/*
* Copyright © 2015 Broadcom
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
/**
* @file vc4_opt_constant_folding.c
*
* Simple constant folding pass to clean up operations on only constants,
* which we might have generated within vc4_program.c.
*/
#include "vc4_qir.h"
#include "util/u_math.h"
static bool debug;
static void
dump_from(struct vc4_compile *c, struct qinst *inst)
{
if (!debug)
return;
fprintf(stderr, "optimizing: ");
qir_dump_inst(c, inst);
fprintf(stderr, "\n");
}
static void
dump_to(struct vc4_compile *c, struct qinst *inst)
{
if (!debug)
return;
fprintf(stderr, "to: ");
qir_dump_inst(c, inst);
fprintf(stderr, "\n");
}
static bool
constant_fold(struct vc4_compile *c, struct qinst *inst)
{
int nsrc = qir_get_op_nsrc(inst->op);
uint32_t ui[nsrc];
for (int i = 0; i < nsrc; i++) {
struct qreg reg = inst->src[i];
if (reg.file == QFILE_UNIF &&
c->uniform_contents[reg.index] == QUNIFORM_CONSTANT) {
ui[i] = c->uniform_data[reg.index];
} else if (reg.file == QFILE_SMALL_IMM) {
ui[i] = reg.index;
} else {
return false;
}
}
uint32_t result = 0;
switch (inst->op) {
case QOP_SHR:
result = ui[0] >> ui[1];
break;
default:
return false;
}
dump_from(c, inst);
inst->src[0] = qir_uniform_ui(c, result);
for (int i = 1; i < nsrc; i++)
inst->src[i] = c->undef;
inst->op = QOP_MOV;
dump_to(c, inst);
return true;
}
bool
qir_opt_constant_folding(struct vc4_compile *c)
{
bool progress = false;
list_for_each_entry(struct qinst, inst, &c->instructions, link) {
if (constant_fold(c, inst))
progress = true;
}
return progress;
}
|
