src/compiler/nir/nir_opt_intrinsics.c

   1 /*
   2  * Copyright © 2017 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 #include "nir.h"
  25 #include "nir_builder.h"
  26
  27 /**
  28  * \file nir_opt_intrinsics.c
  29  */
  30
  31 static bool
  32 opt_intrinsics_impl(nir_function_impl *impl)
  33 {
  34    nir_builder b;
  35    nir_builder_init(&b, impl);
  36    bool progress = false;
  37
  38    nir_foreach_block(block, impl) {
  39       nir_foreach_instr_safe(instr, block) {
  40          if (instr->type != nir_instr_type_intrinsic)
  41             continue;
  42
  43          nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
  44          nir_ssa_def *replacement = NULL;
  45          b.cursor = nir_before_instr(instr);
  46
  47          switch (intrin->intrinsic) {
  48          case nir_intrinsic_vote_any:
  49          case nir_intrinsic_vote_all:
  50             if (nir_src_as_const_value(intrin->src[0]))
  51                replacement = nir_ssa_for_src(&b, intrin->src[0], 1);
  52             break;
  53          case nir_intrinsic_vote_eq:
  54             if (nir_src_as_const_value(intrin->src[0]))
  55                replacement = nir_imm_int(&b, NIR_TRUE);
  56             break;
  57          case nir_intrinsic_ballot: {
  58             assert(b.shader->options->max_subgroup_size != 0);
  59             if (b.shader->options->max_subgroup_size > 32 ||
  60                 intrin->dest.ssa.bit_size <= 32)
  61                continue;
  62
  63             nir_intrinsic_instr *ballot =
  64                nir_intrinsic_instr_create(b.shader, nir_intrinsic_ballot);
  65             nir_ssa_dest_init(&ballot->instr, &ballot->dest, 1, 32, NULL);
  66             nir_src_copy(&ballot->src[0], &intrin->src[0], ballot);
  67
  68             nir_builder_instr_insert(&b, &ballot->instr);
  69
  70             replacement = nir_pack_64_2x32_split(&b,
  71                                                  &ballot->dest.ssa,
  72                                                  nir_imm_int(&b, 0));
  73             break;
  74          }
  75          default:
  76             break;
  77          }
  78
  79          if (!replacement)
  80             continue;
  81
  82          nir_ssa_def_rewrite_uses(&intrin->dest.ssa,
  83                                   nir_src_for_ssa(replacement));
  84          nir_instr_remove(instr);
  85          progress = true;
  86       }
  87    }
  88
  89    return progress;
  90 }
  91
  92 bool
  93 nir_opt_intrinsics(nir_shader *shader)
  94 {
  95    bool progress = false;
  96
  97    nir_foreach_function(function, shader) {
  98       if (!function->impl)
  99          continue;
 100
 101       if (opt_intrinsics_impl(function->impl)) {
 102          progress = true;
 103          nir_metadata_preserve(function->impl, nir_metadata_block_index |
 104                                                nir_metadata_dominance);
 105       }
 106    }
 107
 108    return progress;
 109 }