1 /*
2 * Copyright © 2010 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
21 * DEALINGS IN THE SOFTWARE.
22 */
23
24 /**
25 * \file opt_swizzle_swizzle.cpp
26 *
27 * Eliminates the second swizzle in a swizzle chain.
28 */
29
30 #include "ir.h"
31 #include "ir_visitor.h"
32 #include "ir_optimization.h"
33 #include "glsl_types.h"
34
35 namespace {
36
37 class ir_swizzle_swizzle_visitor : public ir_hierarchical_visitor {
38 public:
ir_swizzle_swizzle_visitor()39 ir_swizzle_swizzle_visitor()
40 {
41 progress = false;
42 }
43
44 virtual ir_visitor_status visit_enter(ir_swizzle *);
45
46 bool progress;
47 };
48
49 } /* unnamed namespace */
50
51 ir_visitor_status
visit_enter(ir_swizzle * ir)52 ir_swizzle_swizzle_visitor::visit_enter(ir_swizzle *ir)
53 {
54 int mask2[4];
55
56 ir_swizzle *swiz2 = ir->val->as_swizzle();
57 if (!swiz2)
58 return visit_continue;
59
60 memset(&mask2, 0, sizeof(mask2));
61 if (swiz2->mask.num_components >= 1)
62 mask2[0] = swiz2->mask.x;
63 if (swiz2->mask.num_components >= 2)
64 mask2[1] = swiz2->mask.y;
65 if (swiz2->mask.num_components >= 3)
66 mask2[2] = swiz2->mask.z;
67 if (swiz2->mask.num_components >= 4)
68 mask2[3] = swiz2->mask.w;
69
70 if (ir->mask.num_components >= 1)
71 ir->mask.x = mask2[ir->mask.x];
72 if (ir->mask.num_components >= 2)
73 ir->mask.y = mask2[ir->mask.y];
74 if (ir->mask.num_components >= 3)
75 ir->mask.z = mask2[ir->mask.z];
76 if (ir->mask.num_components >= 4)
77 ir->mask.w = mask2[ir->mask.w];
78
79 ir->val = swiz2->val;
80
81 this->progress = true;
82
83 return visit_continue;
84 }
85
86 /**
87 * Does a copy propagation pass on the code present in the instruction stream.
88 */
89 bool
do_swizzle_swizzle(exec_list * instructions)90 do_swizzle_swizzle(exec_list *instructions)
91 {
92 ir_swizzle_swizzle_visitor v;
93
94 v.run(instructions);
95
96 return v.progress;
97 }
98