2015-08-05 00:25:24 +01:00
|
|
|
/*
|
|
|
|
* 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.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include "nir.h"
|
|
|
|
|
|
|
|
/** @file nir_opt_undef.c
|
|
|
|
*
|
|
|
|
* Handles optimization of operations involving ssa_undef. For now, we just
|
|
|
|
* make sure that csels between undef and some other value just give the other
|
|
|
|
* value (on the assumption that the condition's going to be choosing the
|
|
|
|
* defined value). This reduces work after if flattening when each side of
|
|
|
|
* the if is defining a variable.
|
|
|
|
*
|
|
|
|
* Some day, we may find some use for making other operations consuming an
|
|
|
|
* undef arg output undef, but I don't know of any cases currently.
|
|
|
|
*/
|
|
|
|
|
|
|
|
static bool
|
|
|
|
opt_undef_alu(nir_alu_instr *instr)
|
|
|
|
{
|
|
|
|
if (instr->op != nir_op_bcsel && instr->op != nir_op_fcsel)
|
|
|
|
return false;
|
|
|
|
|
|
|
|
assert(instr->dest.dest.is_ssa);
|
|
|
|
|
|
|
|
for (int i = 1; i <= 2; i++) {
|
|
|
|
if (!instr->src[i].src.is_ssa)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
nir_instr *parent = instr->src[i].src.ssa->parent_instr;
|
|
|
|
if (parent->type != nir_instr_type_ssa_undef)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
/* We can't just use nir_alu_src_copy, because we need the def/use
|
|
|
|
* updated.
|
|
|
|
*/
|
|
|
|
nir_instr_rewrite_src(&instr->instr, &instr->src[0].src,
|
|
|
|
instr->src[i == 1 ? 2 : 1].src);
|
|
|
|
nir_alu_src_copy(&instr->src[0], &instr->src[i == 1 ? 2 : 1],
|
|
|
|
ralloc_parent(instr));
|
|
|
|
|
|
|
|
nir_src empty_src;
|
|
|
|
memset(&empty_src, 0, sizeof(empty_src));
|
|
|
|
nir_instr_rewrite_src(&instr->instr, &instr->src[1].src, empty_src);
|
|
|
|
nir_instr_rewrite_src(&instr->instr, &instr->src[2].src, empty_src);
|
|
|
|
instr->op = nir_op_imov;
|
|
|
|
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
|
|
|
|
bool
|
|
|
|
nir_opt_undef(nir_shader *shader)
|
|
|
|
{
|
|
|
|
bool progress = false;
|
|
|
|
|
2015-12-26 18:00:47 +00:00
|
|
|
nir_foreach_function(shader, function) {
|
|
|
|
if (function->impl) {
|
2016-04-12 19:46:03 +01:00
|
|
|
nir_foreach_block(block, function->impl) {
|
2016-04-27 02:34:19 +01:00
|
|
|
nir_foreach_instr_safe(instr, block) {
|
2016-04-12 19:46:03 +01:00
|
|
|
if (instr->type == nir_instr_type_alu)
|
|
|
|
if (opt_undef_alu(nir_instr_as_alu(instr)))
|
|
|
|
progress = true;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2015-08-05 00:25:24 +01:00
|
|
|
if (progress)
|
2015-12-26 18:00:47 +00:00
|
|
|
nir_metadata_preserve(function->impl,
|
2015-08-05 00:25:24 +01:00
|
|
|
nir_metadata_block_index |
|
|
|
|
nir_metadata_dominance);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return progress;
|
|
|
|
}
|