--- /dev/null
+/*
+ * Copyright © 2016 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 "anv_nir.h"
+#include "nir/nir_builder.h"
+
+static nir_ssa_def *
+load_frag_coord(nir_builder *b)
+{
+ nir_foreach_variable(var, &b->shader->inputs) {
+ if (var->data.location == VARYING_SLOT_POS)
+ return nir_load_var(b, var);
+ }
+
+ nir_variable *pos = nir_variable_create(b->shader, nir_var_shader_in,
+ glsl_vec4_type(), NULL);
+ pos->data.location = VARYING_SLOT_POS;
+ pos->data.origin_upper_left = true;
+
+ return nir_load_var(b, pos);
+}
+
+static void
+try_lower_input_load(nir_function_impl *impl, nir_intrinsic_instr *load)
+{
+
+ const struct glsl_type *image_type =
+ glsl_without_array(load->variables[0]->var->type);
+ enum glsl_sampler_dim image_dim = glsl_get_sampler_dim(image_type);
+ if (image_dim != GLSL_SAMPLER_DIM_SUBPASS &&
+ image_dim != GLSL_SAMPLER_DIM_SUBPASS_MS)
+ return;
+
+ const bool multisampled = (image_dim == GLSL_SAMPLER_DIM_SUBPASS_MS);
+
+ nir_builder b;
+ nir_builder_init(&b, impl);
+ b.cursor = nir_before_instr(&load->instr);
+
+ nir_ssa_def *frag_coord = nir_f2i(&b, load_frag_coord(&b));
+ nir_ssa_def *offset = nir_ssa_for_src(&b, load->src[0], 2);
+ nir_ssa_def *pos = nir_iadd(&b, frag_coord, offset);
+
+ nir_ssa_def *layer =
+ nir_load_system_value(&b, nir_intrinsic_load_layer_id, 0);
+ nir_ssa_def *coord =
+ nir_vec3(&b, nir_channel(&b, pos, 0), nir_channel(&b, pos, 1), layer);
+
+ nir_tex_instr *tex = nir_tex_instr_create(b.shader, 2 + multisampled);
+
+ tex->op = nir_texop_txf;
+
+ switch (glsl_get_sampler_result_type(image_type)) {
+ case GLSL_TYPE_FLOAT:
+ tex->dest_type = nir_type_float;
+ break;
+ case GLSL_TYPE_INT:
+ tex->dest_type = nir_type_int;
+ break;
+ case GLSL_TYPE_UINT:
+ tex->dest_type = nir_type_uint;
+ break;
+ default:
+ unreachable("Invalid image type");
+ }
+ tex->is_array = true;
+ tex->is_shadow = false;
+
+ tex->texture =
+ nir_deref_as_var(nir_copy_deref(tex, &load->variables[0]->deref));
+ tex->sampler = NULL;
+ tex->texture_index = 0;
+ tex->sampler_index = 0;
+
+ tex->src[0].src_type = nir_tex_src_coord;
+ tex->src[0].src = nir_src_for_ssa(coord);
+ tex->coord_components = 3;
+
+ tex->src[1].src_type = nir_tex_src_lod;
+ tex->src[1].src = nir_src_for_ssa(nir_imm_int(&b, 0));
+
+ if (image_dim == GLSL_SAMPLER_DIM_SUBPASS_MS) {
+ tex->op = nir_texop_txf_ms;
+
+ nir_ssa_def *sample_id =
+ nir_load_system_value(&b, nir_intrinsic_load_sample_id, 0);
+ tex->src[2].src_type = nir_tex_src_ms_index;
+ tex->src[2].src = nir_src_for_ssa(sample_id);
+ }
+
+ nir_ssa_dest_init(&tex->instr, &tex->dest, 4, 32, NULL);
+ nir_builder_instr_insert(&b, &tex->instr);
+
+ nir_ssa_def_rewrite_uses(&load->dest.ssa,
+ nir_src_for_ssa(&tex->dest.ssa));
+}
+
+void
+anv_nir_lower_input_attachments(nir_shader *shader)
+{
+ assert(shader->stage == MESA_SHADER_FRAGMENT);
+
+ nir_foreach_function(function, shader) {
+ if (!function->impl)
+ continue;
+
+ nir_foreach_block(block, function->impl) {
+ nir_foreach_instr(instr, block) {
+ if (instr->type != nir_instr_type_intrinsic)
+ continue;
+
+ nir_intrinsic_instr *load = nir_instr_as_intrinsic(instr);
+
+ if (load->intrinsic != nir_intrinsic_image_load)
+ continue;
+
+ try_lower_input_load(function->impl, load);
+ }
+ }
+ }
+}