mesa/src/compiler/nir/nir_remove_tex_shadow.c

/*
 * Copyright © 2023 Intel Corporation
 *
 * 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"
#include "nir_builder.h"

static bool
remove_tex_shadow(struct nir_builder *b, nir_instr *instr, void *data)
{
   if (instr->type != nir_instr_type_tex)
      return false;

   nir_tex_instr *tex = nir_instr_as_tex(instr);

   if (!tex->is_shadow)
      return false;

   unsigned *textures_bitmask = data;

   if (BITFIELD_BIT(tex->texture_index) & ~*textures_bitmask)
      return false;

   int index = nir_tex_instr_src_index(tex, nir_tex_src_comparator);

   if (index != -1) {
      tex->is_shadow = false;
      nir_tex_instr_remove_src(tex, index);
      return true;
   }

   return false;
}

bool
nir_remove_tex_shadow(nir_shader *shader, unsigned textures_bitmask)
{
   return nir_shader_instructions_pass(shader, remove_tex_shadow,
                                       nir_metadata_none, &textures_bitmask);
}