+++ /dev/null
-/*
- * Copyright © 2014 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"
-
-struct locals_to_regs_state {
- nir_builder builder;
-
- /* A hash table mapping derefs to registers */
- struct hash_table *regs_table;
-
- /* Bit size to use for boolean registers */
- uint8_t bool_bitsize;
-
- bool progress;
-};
-
-/* The following two functions implement a hash and equality check for
- * variable dreferences. When the hash or equality function encounters an
- * array, it ignores the offset and whether it is direct or indirect
- * entirely.
- */
-static uint32_t
-hash_deref(const void *void_deref)
-{
- uint32_t hash = 0;
-
- for (const nir_deref_instr *deref = void_deref; deref;
- deref = nir_deref_instr_parent(deref)) {
- switch (deref->deref_type) {
- case nir_deref_type_var:
- return XXH32(&deref->var, sizeof(deref->var), hash);
-
- case nir_deref_type_array:
- continue; /* Do nothing */
-
- case nir_deref_type_struct:
- hash = XXH32(&deref->strct.index, sizeof(deref->strct.index), hash);
- continue;
-
- default:
- unreachable("Invalid deref type");
- }
- }
-
- unreachable("We should have hit a variable dereference");
-}
-
-static bool
-derefs_equal(const void *void_a, const void *void_b)
-{
- for (const nir_deref_instr *a = void_a, *b = void_b; a || b;
- a = nir_deref_instr_parent(a), b = nir_deref_instr_parent(b)) {
- if (a->deref_type != b->deref_type)
- return false;
-
- switch (a->deref_type) {
- case nir_deref_type_var:
- return a->var == b->var;
-
- case nir_deref_type_array:
- continue; /* Do nothing */
-
- case nir_deref_type_struct:
- if (a->strct.index != b->strct.index)
- return false;
- continue;
-
- default:
- unreachable("Invalid deref type");
- }
- }
-
- unreachable("We should have hit a variable dereference");
-}
-
-static nir_register *
-get_reg_for_deref(nir_deref_instr *deref, struct locals_to_regs_state *state)
-{
- uint32_t hash = hash_deref(deref);
-
- assert(nir_deref_instr_get_variable(deref)->constant_initializer == NULL &&
- nir_deref_instr_get_variable(deref)->pointer_initializer == NULL);
-
- struct hash_entry *entry =
- _mesa_hash_table_search_pre_hashed(state->regs_table, hash, deref);
- if (entry)
- return entry->data;
-
- unsigned array_size = 1;
- for (nir_deref_instr *d = deref; d; d = nir_deref_instr_parent(d)) {
- if (d->deref_type == nir_deref_type_array)
- array_size *= glsl_get_length(nir_deref_instr_parent(d)->type);
- }
-
- assert(glsl_type_is_vector_or_scalar(deref->type));
-
- nir_register *reg = nir_local_reg_create(state->builder.impl);
- reg->num_components = glsl_get_vector_elements(deref->type);
- reg->num_array_elems = array_size > 1 ? array_size : 0;
- reg->bit_size = glsl_get_bit_size(deref->type);
-
- if (reg->bit_size == 1)
- reg->bit_size = state->bool_bitsize;
-
- _mesa_hash_table_insert_pre_hashed(state->regs_table, hash, deref, reg);
-
- return reg;
-}
-
-static nir_src
-get_deref_reg_src(nir_deref_instr *deref, struct locals_to_regs_state *state)
-{
- nir_builder *b = &state->builder;
-
- nir_src src;
-
- src.is_ssa = false;
- src.reg.reg = get_reg_for_deref(deref, state);
- src.reg.base_offset = 0;
- src.reg.indirect = NULL;
-
- /* It is possible for a user to create a shader that has an array with a
- * single element and then proceed to access it indirectly. Indirectly
- * accessing a non-array register is not allowed in NIR. In order to
- * handle this case we just convert it to a direct reference.
- */
- if (src.reg.reg->num_array_elems == 0)
- return src;
-
- unsigned inner_array_size = 1;
- for (const nir_deref_instr *d = deref; d; d = nir_deref_instr_parent(d)) {
- if (d->deref_type != nir_deref_type_array)
- continue;
-
- if (nir_src_is_const(d->arr.index) && !src.reg.indirect) {
- src.reg.base_offset += nir_src_as_uint(d->arr.index) *
- inner_array_size;
- } else {
- if (src.reg.indirect) {
- assert(src.reg.base_offset == 0);
- } else {
- src.reg.indirect = gc_alloc(gc_get_context(deref), nir_src, 1);
- *src.reg.indirect =
- nir_src_for_ssa(nir_imm_int(b, src.reg.base_offset));
- src.reg.base_offset = 0;
- }
-
- assert(src.reg.indirect->is_ssa);
- nir_ssa_def *index = nir_i2iN(b, nir_ssa_for_src(b, d->arr.index, 1), 32);
- src.reg.indirect->ssa =
- nir_iadd(b, src.reg.indirect->ssa,
- nir_imul_imm(b, index, inner_array_size));
- }
-
- inner_array_size *= glsl_get_length(nir_deref_instr_parent(d)->type);
- }
-
- return src;
-}
-
-static bool
-lower_locals_to_regs_block(nir_block *block,
- struct locals_to_regs_state *state)
-{
- nir_builder *b = &state->builder;
-
- nir_foreach_instr_safe(instr, block) {
- if (instr->type != nir_instr_type_intrinsic)
- continue;
-
- nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
-
- switch (intrin->intrinsic) {
- case nir_intrinsic_load_deref: {
- nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]);
- if (!nir_deref_mode_is(deref, nir_var_function_temp))
- continue;
-
- b->cursor = nir_before_instr(&intrin->instr);
-
- nir_alu_instr *mov = nir_alu_instr_create(b->shader, nir_op_mov);
- mov->src[0].src = get_deref_reg_src(deref, state);
-
- if (mov->src[0].src.reg.reg->num_array_elems != 0 &&
- mov->src[0].src.reg.base_offset >= mov->src[0].src.reg.reg->num_array_elems) {
- /* out-of-bounds read, return 0 instead. */
- mov->src[0].src = nir_src_for_ssa(nir_imm_intN_t(b, 0, mov->src[0].src.reg.reg->bit_size));
- for (int i = 0; i < intrin->num_components; i++)
- mov->src[0].swizzle[i] = 0;
- }
-
- mov->dest.write_mask = (1 << intrin->num_components) - 1;
-
- if (intrin->dest.is_ssa) {
- nir_ssa_dest_init(&mov->instr, &mov->dest.dest,
- intrin->num_components,
- intrin->dest.ssa.bit_size);
- nir_ssa_def_rewrite_uses(&intrin->dest.ssa,
- &mov->dest.dest.ssa);
- } else {
- nir_dest_copy(&mov->dest.dest, &intrin->dest, &mov->instr);
- }
- nir_builder_instr_insert(b, &mov->instr);
-
- nir_instr_remove(&intrin->instr);
- state->progress = true;
- break;
- }
-
- case nir_intrinsic_store_deref: {
- nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]);
- if (!nir_deref_mode_is(deref, nir_var_function_temp))
- continue;
-
- b->cursor = nir_before_instr(&intrin->instr);
-
- nir_src reg_src = get_deref_reg_src(deref, state);
-
- if (reg_src.reg.reg->num_array_elems != 0 &&
- reg_src.reg.base_offset >= reg_src.reg.reg->num_array_elems) {
- /* Out of bounds write, just eliminate it. */
- nir_instr_remove(&intrin->instr);
- state->progress = true;
- break;
- }
-
- nir_alu_instr *mov = nir_alu_instr_create(b->shader, nir_op_mov);
-
- nir_src_copy(&mov->src[0].src, &intrin->src[1], &mov->instr);
-
- /* The normal NIR SSA copy propagate pass can't happen after this pass,
- * so do an ad-hoc copy propagate since this ALU op can do swizzles
- * while the deref couldn't.
- */
- if (mov->src[0].src.is_ssa) {
- nir_instr *parent = mov->src[0].src.ssa->parent_instr;
- if (parent->type == nir_instr_type_alu) {
- nir_alu_instr *parent_alu = nir_instr_as_alu(parent);
- if (parent_alu->op == nir_op_mov && parent_alu->src[0].src.is_ssa) {
- for (unsigned i = 0; i < intrin->num_components; i++)
- mov->src[0].swizzle[i] = parent_alu->src[0].swizzle[mov->src[0].swizzle[i]];
- mov->src[0].abs = parent_alu->src[0].abs;
- mov->src[0].negate = parent_alu->src[0].negate;
- mov->src[0].src = parent_alu->src[0].src;
- }
- }
- }
-
- mov->dest.write_mask = nir_intrinsic_write_mask(intrin);
- mov->dest.dest.is_ssa = false;
- mov->dest.dest.reg.reg = reg_src.reg.reg;
- mov->dest.dest.reg.base_offset = reg_src.reg.base_offset;
- mov->dest.dest.reg.indirect = reg_src.reg.indirect;
-
- nir_builder_instr_insert(b, &mov->instr);
-
- nir_instr_remove(&intrin->instr);
- state->progress = true;
- break;
- }
-
- case nir_intrinsic_copy_deref:
- unreachable("There should be no copies whatsoever at this point");
- break;
-
- default:
- continue;
- }
- }
-
- return true;
-}
-
-static bool
-nir_lower_locals_to_regs_impl(nir_function_impl *impl, uint8_t bool_bitsize)
-{
- struct locals_to_regs_state state;
-
- state.builder = nir_builder_create(impl);
- state.progress = false;
- state.regs_table = _mesa_hash_table_create(NULL, hash_deref, derefs_equal);
- state.bool_bitsize = bool_bitsize;
-
- nir_metadata_require(impl, nir_metadata_dominance);
-
- nir_foreach_block(block, impl) {
- lower_locals_to_regs_block(block, &state);
- }
-
- nir_metadata_preserve(impl, nir_metadata_block_index |
- nir_metadata_dominance);
-
- _mesa_hash_table_destroy(state.regs_table, NULL);
-
- return state.progress;
-}
-
-bool
-nir_lower_locals_to_regs(nir_shader *shader, uint8_t bool_bitsize)
-{
- bool progress = false;
-
- nir_foreach_function_impl(impl, shader) {
- progress = nir_lower_locals_to_regs_impl(impl, bool_bitsize) || progress;
- }
-
- return progress;
-}
projects / platform / upstream / mesa.git / commitdiff