src/intel/vulkan/anv_nir_lower_input_attachments.c

   1 /*
   2  * Copyright © 2016 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 "anv_nir.h"
  25 #include "nir/nir_builder.h"
  26
  27 static nir_ssa_def *
  28 load_frag_coord(nir_builder *b)
  29 {
  30    nir_foreach_variable(var, &b->shader->inputs) {
  31       if (var->data.location == VARYING_SLOT_POS)
  32          return nir_load_var(b, var);
  33    }
  34
  35    nir_variable *pos = nir_variable_create(b->shader, nir_var_shader_in,
  36                                            glsl_vec4_type(), NULL);
  37    pos->data.location = VARYING_SLOT_POS;
  38    pos->data.origin_upper_left = true;
  39
  40    return nir_load_var(b, pos);
  41 }
  42
  43 static void
  44 try_lower_input_load(nir_function_impl *impl, nir_intrinsic_instr *load)
  45 {
  46    nir_deref_instr *deref = nir_src_as_deref(load->src[0]);
  47    assert(glsl_type_is_image(deref->type));
  48
  49    enum glsl_sampler_dim image_dim = glsl_get_sampler_dim(deref->type);
  50    if (image_dim != GLSL_SAMPLER_DIM_SUBPASS &&
  51        image_dim != GLSL_SAMPLER_DIM_SUBPASS_MS)
  52       return;
  53
  54    const bool multisampled = (image_dim == GLSL_SAMPLER_DIM_SUBPASS_MS);
  55
  56    nir_builder b;
  57    nir_builder_init(&b, impl);
  58    b.cursor = nir_instr_remove(&load->instr);
  59
  60    nir_ssa_def *frag_coord = nir_f2i32(&b, load_frag_coord(&b));
  61    nir_ssa_def *offset = nir_ssa_for_src(&b, load->src[1], 2);
  62    nir_ssa_def *pos = nir_iadd(&b, frag_coord, offset);
  63
  64    nir_ssa_def *layer = nir_load_layer_id(&b);
  65    nir_ssa_def *coord =
  66       nir_vec3(&b, nir_channel(&b, pos, 0), nir_channel(&b, pos, 1), layer);
  67
  68    nir_tex_instr *tex = nir_tex_instr_create(b.shader, 3 + multisampled);
  69
  70    tex->op = nir_texop_txf;
  71
  72    switch (glsl_get_sampler_result_type(deref->type)) {
  73    case GLSL_TYPE_FLOAT:
  74       tex->dest_type = nir_type_float;
  75       break;
  76    case GLSL_TYPE_INT:
  77       tex->dest_type = nir_type_int;
  78       break;
  79    case GLSL_TYPE_UINT:
  80       tex->dest_type = nir_type_uint;
  81       break;
  82    default:
  83       unreachable("Invalid image type");
  84    }
  85    tex->is_array = true;
  86    tex->is_shadow = false;
  87
  88    tex->texture_index = 0;
  89    tex->sampler_index = 0;
  90
  91    tex->src[0].src_type = nir_tex_src_texture_deref;
  92    tex->src[0].src = nir_src_for_ssa(&deref->dest.ssa);
  93
  94    tex->src[1].src_type = nir_tex_src_coord;
  95    tex->src[1].src = nir_src_for_ssa(coord);
  96    tex->coord_components = 3;
  97
  98    tex->src[2].src_type = nir_tex_src_lod;
  99    tex->src[2].src = nir_src_for_ssa(nir_imm_int(&b, 0));
 100
 101    if (image_dim == GLSL_SAMPLER_DIM_SUBPASS_MS) {
 102       tex->op = nir_texop_txf_ms;
 103       tex->src[3].src_type = nir_tex_src_ms_index;
 104       tex->src[3].src = load->src[2];
 105    }
 106
 107    nir_ssa_dest_init(&tex->instr, &tex->dest, 4, 32, NULL);
 108    nir_builder_instr_insert(&b, &tex->instr);
 109
 110    nir_ssa_def_rewrite_uses(&load->dest.ssa,
 111                             nir_src_for_ssa(&tex->dest.ssa));
 112 }
 113
 114 void
 115 anv_nir_lower_input_attachments(nir_shader *shader)
 116 {
 117    assert(shader->info.stage == MESA_SHADER_FRAGMENT);
 118
 119    nir_foreach_function(function, shader) {
 120       if (!function->impl)
 121          continue;
 122
 123       nir_foreach_block(block, function->impl) {
 124          nir_foreach_instr_safe(instr, block) {
 125             if (instr->type != nir_instr_type_intrinsic)
 126                continue;
 127
 128             nir_intrinsic_instr *load = nir_instr_as_intrinsic(instr);
 129
 130             if (load->intrinsic != nir_intrinsic_image_deref_load)
 131                continue;
 132
 133             try_lower_input_load(function->impl, load);
 134          }
 135       }
 136    }
 137 }