--- /dev/null
+/*
+ * Copyright (C) 2005-2007 Brian Paul All Rights Reserved.
+ * Copyright (C) 2008 VMware, Inc. All Rights Reserved.
+ * Copyright © 2014 Intel Corporation
+ * Copyright © 2017 Advanced Micro Devices, Inc.
+ *
+ * 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.
+ */
+
+/**
+ * \file
+ *
+ * Lower sampler and image references of (non-bindless) uniforms by removing
+ * struct dereferences, and synthesizing new uniform variables without structs
+ * if required.
+ *
+ * This will allow backends to have a simple, uniform treatment of bindless and
+ * non-bindless samplers and images.
+ *
+ * Example:
+ *
+ * struct S {
+ * sampler2D tex[2];
+ * sampler2D other;
+ * };
+ * uniform S s[2];
+ *
+ * tmp = texture(s[n].tex[m], coord);
+ *
+ * Becomes:
+ *
+ * decl_var uniform INTERP_MODE_NONE sampler2D[2][2] lower@s.tex (...)
+ *
+ * vec1 32 ssa_idx = $(2 * n + m)
+ * vec4 32 ssa_out = tex ssa_coord (coord), lower@s.tex[n][m] (texture), lower@s.tex[n][m] (sampler)
+ *
+ * and lower@s.tex has var->data.binding set to the base index as defined by
+ * the opaque uniform mapping.
+ */
+
+#include "nir.h"
+#include "nir_builder.h"
+#include "compiler/glsl/ir_uniform.h"
+
+#include "main/compiler.h"
+#include "main/mtypes.h"
+#include "program/prog_parameter.h"
+#include "program/program.h"
+
+struct lower_samplers_as_deref_state {
+ nir_shader *shader;
+ const struct gl_shader_program *shader_program;
+ struct hash_table *remap_table;
+};
+
+static void
+remove_struct_derefs(nir_deref *tail,
+ struct lower_samplers_as_deref_state *state,
+ nir_builder *b, char **path, unsigned *location)
+{
+ if (!tail->child)
+ return;
+
+ switch (tail->child->deref_type) {
+ case nir_deref_type_array: {
+ unsigned length = glsl_get_length(tail->type);
+
+ remove_struct_derefs(tail->child, state, b, path, location);
+
+ tail->type = glsl_get_array_instance(tail->child->type, length);
+ break;
+ }
+
+ case nir_deref_type_struct: {
+ nir_deref_struct *deref_struct = nir_deref_as_struct(tail->child);
+
+ *location += glsl_get_record_location_offset(tail->type, deref_struct->index);
+ ralloc_asprintf_append(path, ".%s",
+ glsl_get_struct_elem_name(tail->type, deref_struct->index));
+
+ remove_struct_derefs(tail->child, state, b, path, location);
+
+ /* Drop the struct deref and re-parent. */
+ ralloc_steal(tail, tail->child->child);
+ tail->type = tail->child->type;
+ tail->child = tail->child->child;
+ break;
+ }
+
+ default:
+ unreachable("Invalid deref type");
+ break;
+ }
+}
+
+static void
+lower_deref(nir_deref_var *deref,
+ struct lower_samplers_as_deref_state *state,
+ nir_builder *b)
+{
+ nir_variable *var = deref->var;
+ gl_shader_stage stage = state->shader->stage;
+ unsigned location = var->data.location;
+ unsigned binding;
+ const struct glsl_type *orig_type = deref->deref.type;
+ char *path;
+
+ assert(var->data.mode == nir_var_uniform);
+
+ path = ralloc_asprintf(state->remap_table, "lower@%s", var->name);
+ remove_struct_derefs(&deref->deref, state, b, &path, &location);
+
+ assert(location < state->shader_program->data->NumUniformStorage &&
+ state->shader_program->data->UniformStorage[location].opaque[stage].active);
+
+ binding = state->shader_program->data->UniformStorage[location].opaque[stage].index;
+
+ if (orig_type == deref->deref.type) {
+ /* Fast path: We did not encounter any struct derefs. */
+ var->data.binding = binding;
+ return;
+ }
+
+ uint32_t hash = _mesa_key_hash_string(path);
+ struct hash_entry *h =
+ _mesa_hash_table_search_pre_hashed(state->remap_table, hash, path);
+
+ if (h) {
+ var = (nir_variable *)h->data;
+ } else {
+ var = nir_variable_create(state->shader, nir_var_uniform, deref->deref.type, path);
+ var->data.binding = binding;
+ _mesa_hash_table_insert_pre_hashed(state->remap_table, hash, path, var);
+ }
+
+ deref->var = var;
+}
+
+static bool
+lower_sampler(nir_tex_instr *instr, struct lower_samplers_as_deref_state *state,
+ nir_builder *b)
+{
+ /* In GLSL, we only fill out the texture field. The sampler is inferred */
+ assert(instr->texture != NULL);
+ assert(instr->sampler == NULL);
+
+ b->cursor = nir_before_instr(&instr->instr);
+ lower_deref(instr->texture, state, b);
+
+ if (instr->op != nir_texop_txf_ms &&
+ instr->op != nir_texop_txf_ms_mcs &&
+ instr->op != nir_texop_samples_identical) {
+ nir_instr_rewrite_deref(&instr->instr, &instr->sampler,
+ nir_deref_var_clone(instr->texture, instr));
+ } else {
+ assert(!instr->sampler);
+ }
+
+ return true;
+}
+
+static bool
+lower_intrinsic(nir_intrinsic_instr *instr,
+ struct lower_samplers_as_deref_state *state,
+ nir_builder *b)
+{
+ if (instr->intrinsic == nir_intrinsic_image_load ||
+ instr->intrinsic == nir_intrinsic_image_store ||
+ instr->intrinsic == nir_intrinsic_image_atomic_add ||
+ instr->intrinsic == nir_intrinsic_image_atomic_min ||
+ instr->intrinsic == nir_intrinsic_image_atomic_max ||
+ instr->intrinsic == nir_intrinsic_image_atomic_and ||
+ instr->intrinsic == nir_intrinsic_image_atomic_or ||
+ instr->intrinsic == nir_intrinsic_image_atomic_xor ||
+ instr->intrinsic == nir_intrinsic_image_atomic_exchange ||
+ instr->intrinsic == nir_intrinsic_image_atomic_comp_swap ||
+ instr->intrinsic == nir_intrinsic_image_size) {
+ b->cursor = nir_before_instr(&instr->instr);
+ lower_deref(instr->variables[0], state, b);
+ return true;
+ }
+
+ return false;
+}
+
+static bool
+lower_impl(nir_function_impl *impl, struct lower_samplers_as_deref_state *state)
+{
+ nir_builder b;
+ nir_builder_init(&b, impl);
+ bool progress = false;
+
+ nir_foreach_block(block, impl) {
+ nir_foreach_instr(instr, block) {
+ if (instr->type == nir_instr_type_tex)
+ progress |= lower_sampler(nir_instr_as_tex(instr), state, &b);
+ else if (instr->type == nir_instr_type_intrinsic)
+ progress |= lower_intrinsic(nir_instr_as_intrinsic(instr), state, &b);
+ }
+ }
+
+ return progress;
+}
+
+bool
+nir_lower_samplers_as_deref(nir_shader *shader,
+ const struct gl_shader_program *shader_program)
+{
+ bool progress = false;
+ struct lower_samplers_as_deref_state state;
+
+ state.shader = shader;
+ state.shader_program = shader_program;
+ state.remap_table = _mesa_hash_table_create(NULL, _mesa_key_hash_string,
+ _mesa_key_string_equal);
+
+ nir_foreach_function(function, shader) {
+ if (function->impl)
+ progress |= lower_impl(function->impl, &state);
+ }
+
+ /* keys are freed automatically by ralloc */
+ _mesa_hash_table_destroy(state.remap_table, NULL);
+
+ return progress;
+}