--- /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.
+ *
+ * Authors:
+ * Jason Ekstrand (jason@jlekstrand.net)
+ *
+ */
+
+/*
+ * This lowering pass converts references to variables with loads/stores to
+ * scratch space based on a few configurable parameters.
+ */
+
+#include "nir.h"
+#include "nir_builder.h"
+#include "nir_deref.h"
+
+static bool
+deref_has_indirect(nir_deref_instr *deref)
+{
+ while (deref->deref_type != nir_deref_type_var) {
+ if (deref->deref_type == nir_deref_type_array &&
+ nir_src_as_const_value(deref->arr.index) == NULL)
+ return true;
+
+ deref = nir_deref_instr_parent(deref);
+ }
+
+ return false;
+}
+
+static void
+lower_load_store(nir_builder *b,
+ nir_intrinsic_instr *intrin,
+ glsl_type_size_align_func size_align)
+{
+ b->cursor = nir_before_instr(&intrin->instr);
+
+ nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]);
+ nir_variable *var = nir_deref_instr_get_variable(deref);
+
+ nir_ssa_def *offset =
+ nir_iadd_imm(b, nir_build_deref_offset(b, deref, size_align),
+ var->data.location);
+
+ unsigned align, UNUSED size;
+ size_align(deref->type, &size, &align);
+
+ if (intrin->intrinsic == nir_intrinsic_load_deref) {
+ nir_intrinsic_instr *load =
+ nir_intrinsic_instr_create(b->shader, nir_intrinsic_load_scratch);
+ load->num_components = intrin->num_components;
+ load->src[0] = nir_src_for_ssa(offset);
+ nir_intrinsic_set_align(load, align, 0);
+ nir_ssa_dest_init(&load->instr, &load->dest,
+ intrin->dest.ssa.num_components,
+ intrin->dest.ssa.bit_size, NULL);
+ nir_builder_instr_insert(b, &load->instr);
+
+ nir_ssa_def *value = &load->dest.ssa;
+ if (glsl_type_is_boolean(deref->type))
+ value = nir_b2i32(b, value);
+
+ nir_ssa_def_rewrite_uses(&intrin->dest.ssa,
+ nir_src_for_ssa(&load->dest.ssa));
+ } else {
+ assert(intrin->intrinsic == nir_intrinsic_store_deref);
+
+ assert(intrin->src[1].is_ssa);
+ nir_ssa_def *value = intrin->src[1].ssa;
+ if (glsl_type_is_boolean(deref->type))
+ value = nir_i2b(b, value);
+
+ nir_intrinsic_instr *store =
+ nir_intrinsic_instr_create(b->shader, nir_intrinsic_store_scratch);
+ store->num_components = intrin->num_components;
+ store->src[0] = nir_src_for_ssa(value);
+ store->src[1] = nir_src_for_ssa(offset);
+ nir_intrinsic_set_write_mask(store, nir_intrinsic_write_mask(intrin));
+ nir_intrinsic_set_align(store, align, 0);
+ nir_builder_instr_insert(b, &store->instr);
+ }
+
+ nir_instr_remove(&intrin->instr);
+ nir_deref_instr_remove_if_unused(deref);
+}
+
+bool
+nir_lower_vars_to_scratch(nir_shader *shader,
+ nir_variable_mode modes,
+ int size_threshold,
+ glsl_type_size_align_func size_align)
+{
+ /* First, we walk the instructions and flag any variables we want to lower
+ * by removing them from their respective list and setting the mode to 0.
+ */
+ nir_foreach_function(function, shader) {
+ nir_foreach_block(block, function->impl) {
+ nir_foreach_instr(instr, block) {
+ if (instr->type != nir_instr_type_intrinsic)
+ continue;
+
+ nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
+ if (intrin->intrinsic != nir_intrinsic_load_deref &&
+ intrin->intrinsic != nir_intrinsic_store_deref)
+ continue;
+
+ nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]);
+ if (!(deref->mode & modes))
+ continue;
+
+ if (!deref_has_indirect(nir_src_as_deref(intrin->src[0])))
+ continue;
+
+ nir_variable *var = nir_deref_instr_get_variable(deref);
+
+ /* We set var->mode to 0 to indicate that a variable will be moved
+ * to scratch. Don't assign a scratch location twice.
+ */
+ if (var->data.mode == 0)
+ continue;
+
+ unsigned var_size, var_align;
+ size_align(var->type, &var_size, &var_align);
+ if (var_size <= size_threshold)
+ continue;
+
+ /* Remove it from its list */
+ exec_node_remove(&var->node);
+ /* Invalid mode used to flag "moving to scratch" */
+ var->data.mode = 0;
+
+ var->data.location = ALIGN_POT(shader->scratch_size, var_align);
+ shader->scratch_size = var->data.location + var_size;
+ }
+ }
+ }
+
+ bool progress = false;
+ nir_foreach_function(function, shader) {
+ if (!function->impl)
+ continue;
+
+ nir_builder build;
+ nir_builder_init(&build, function->impl);
+
+ bool impl_progress = false;
+ nir_foreach_block(block, function->impl) {
+ nir_foreach_instr_safe(instr, block) {
+ if (instr->type != nir_instr_type_intrinsic)
+ continue;
+
+ nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
+ if (intrin->intrinsic != nir_intrinsic_load_deref &&
+ intrin->intrinsic != nir_intrinsic_store_deref)
+ continue;
+
+ nir_variable *var = nir_intrinsic_get_var(intrin, 0);
+ /* Variables flagged for lowering above have mode == 0 */
+ if (!var || var->data.mode)
+ continue;
+
+ lower_load_store(&build, intrin, size_align);
+ impl_progress = true;
+ }
+ }
+
+ if (impl_progress) {
+ progress = true;
+ nir_metadata_preserve(function->impl, nir_metadata_block_index |
+ nir_metadata_dominance);
+ }
+ }
+
+ return progress;
+}
projects / mesa.git / commitdiff