2 * Copyright © 2014 Intel Corporation
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:
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
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
24 * Jason Ekstrand (jason@jlekstrand.net)
25 * Connor Abbott (cwabbott0@gmail.com)
29 #include "nir_instr_set.h"
32 * Implements common subexpression elimination
36 * Visits and CSE's the given block and all its descendants in the dominance
37 * tree recursively. Note that the instr_set is guaranteed to only ever
38 * contain instructions that dominate the current block.
42 cse_block(nir_block
*block
, struct set
*instr_set
)
44 bool progress
= false;
46 nir_foreach_instr_safe(instr
, block
) {
47 if (nir_instr_set_add_or_rewrite(instr_set
, instr
)) {
49 nir_instr_remove(instr
);
53 for (unsigned i
= 0; i
< block
->num_dom_children
; i
++) {
54 nir_block
*child
= block
->dom_children
[i
];
55 progress
|= cse_block(child
, instr_set
);
58 nir_foreach_instr(instr
, block
)
59 nir_instr_set_remove(instr_set
, instr
);
65 nir_opt_cse_impl(nir_function_impl
*impl
)
67 struct set
*instr_set
= nir_instr_set_create(NULL
);
69 nir_metadata_require(impl
, nir_metadata_dominance
);
71 bool progress
= cse_block(nir_start_block(impl
), instr_set
);
74 nir_metadata_preserve(impl
, nir_metadata_block_index
|
75 nir_metadata_dominance
);
77 nir_instr_set_destroy(instr_set
);
82 nir_opt_cse(nir_shader
*shader
)
84 bool progress
= false;
86 nir_foreach_function(function
, shader
) {
88 progress
|= nir_opt_cse_impl(function
->impl
);