src/compiler/nir/nir_opt_barriers.c

   1 /*
   2  * Copyright © 2020 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
  26 static bool
  27 nir_opt_combine_memory_barriers_impl(
  28    nir_function_impl *impl, nir_combine_memory_barrier_cb combine_cb, void *data)
  29 {
  30    bool progress = false;
  31
  32    nir_foreach_block(block, impl) {
  33       nir_intrinsic_instr *prev = NULL;
  34
  35       nir_foreach_instr_safe(instr, block) {
  36          if (instr->type != nir_instr_type_intrinsic) {
  37             prev = NULL;
  38             continue;
  39          }
  40
  41          nir_intrinsic_instr *current = nir_instr_as_intrinsic(instr);
  42          if (current->intrinsic != nir_intrinsic_scoped_barrier ||
  43              nir_intrinsic_execution_scope(current) != NIR_SCOPE_NONE) {
  44             prev = NULL;
  45             continue;
  46          }
  47
  48          if (prev && combine_cb(prev, current, data)) {
  49             nir_instr_remove(&current->instr);
  50             progress = true;
  51          } else {
  52             prev = current;
  53          }
  54       }
  55    }
  56
  57    if (progress) {
  58       nir_metadata_preserve(impl, nir_metadata_block_index |
  59                                   nir_metadata_dominance |
  60                                   nir_metadata_live_ssa_defs);
  61    } else {
  62       nir_metadata_preserve(impl, nir_metadata_all);
  63    }
  64
  65    return progress;
  66 }
  67
  68 /* Combine adjacent scoped memory barriers. */
  69 bool
  70 nir_opt_combine_memory_barriers(
  71    nir_shader *shader, nir_combine_memory_barrier_cb combine_cb, void *data)
  72 {
  73    assert(combine_cb);
  74
  75    bool progress = false;
  76
  77    nir_foreach_function(function, shader) {
  78       if (function->impl &&
  79           nir_opt_combine_memory_barriers_impl(function->impl, combine_cb, data)) {
  80          progress = true;
  81       }
  82    }
  83
  84    return progress;
  85 }