822 lines
26 KiB
C
822 lines
26 KiB
C
/*
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* Copyright © 2014 Intel Corporation
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*
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* Permission is hereby granted, free of charge, to any person obtaining a
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* copy of this software and associated documentation files (the "Software"),
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* to deal in the Software without restriction, including without limitation
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* the rights to use, copy, modify, merge, publish, distribute, sublicense,
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* and/or sell copies of the Software, and to permit persons to whom the
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* Software is furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice (including the next
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* paragraph) shall be included in all copies or substantial portions of the
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* Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
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* IN THE SOFTWARE.
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*
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* Authors:
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* Jason Ekstrand (jason@jlekstrand.net)
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*
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*/
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#include "nir.h"
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#include "nir_builder.h"
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#include "nir_deref.h"
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#include "nir_phi_builder.h"
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#include "nir_vla.h"
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struct deref_node {
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struct deref_node *parent;
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const struct glsl_type *type;
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bool lower_to_ssa;
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/* Only valid for things that end up in the direct list.
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* Note that multiple nir_deref_instrs may correspond to this node, but
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* they will all be equivalent, so any is as good as the other.
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*/
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nir_deref_path path;
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struct exec_node direct_derefs_link;
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struct set *loads;
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struct set *stores;
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struct set *copies;
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struct nir_phi_builder_value *pb_value;
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/* True if this node is fully direct. If set, it must be in the children
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* array of its parent.
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*/
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bool is_direct;
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/* Set on a root node for a variable to indicate that variable is used by a
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* cast or passed through some other sequence of instructions that are not
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* derefs.
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*/
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bool has_complex_use;
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struct deref_node *wildcard;
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struct deref_node *indirect;
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struct deref_node *children[0];
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};
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#define UNDEF_NODE ((struct deref_node *)(uintptr_t)1)
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struct lower_variables_state {
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nir_shader *shader;
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void *dead_ctx;
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nir_function_impl *impl;
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/* A hash table mapping variables to deref_node data */
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struct hash_table *deref_var_nodes;
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/* A hash table mapping fully-qualified direct dereferences, i.e.
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* dereferences with no indirect or wildcard array dereferences, to
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* deref_node data.
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*
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* At the moment, we only lower loads, stores, and copies that can be
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* trivially lowered to loads and stores, i.e. copies with no indirects
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* and no wildcards. If a part of a variable that is being loaded from
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* and/or stored into is also involved in a copy operation with
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* wildcards, then we lower that copy operation to loads and stores, but
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* otherwise we leave copies with wildcards alone. Since the only derefs
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* used in these loads, stores, and trivial copies are ones with no
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* wildcards and no indirects, these are precisely the derefs that we
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* can actually consider lowering.
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*/
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struct exec_list direct_deref_nodes;
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/* Controls whether get_deref_node will add variables to the
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* direct_deref_nodes table. This is turned on when we are initially
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* scanning for load/store instructions. It is then turned off so we
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* don't accidentally change the direct_deref_nodes table while we're
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* iterating throug it.
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*/
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bool add_to_direct_deref_nodes;
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struct nir_phi_builder *phi_builder;
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};
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static struct deref_node *
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deref_node_create(struct deref_node *parent,
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const struct glsl_type *type,
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bool is_direct, void *mem_ctx)
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{
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size_t size = sizeof(struct deref_node) +
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glsl_get_length(type) * sizeof(struct deref_node *);
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struct deref_node *node = rzalloc_size(mem_ctx, size);
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node->type = type;
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node->parent = parent;
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exec_node_init(&node->direct_derefs_link);
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node->is_direct = is_direct;
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return node;
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}
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/* Returns the deref node associated with the given variable. This will be
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* the root of the tree representing all of the derefs of the given variable.
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*/
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static struct deref_node *
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get_deref_node_for_var(nir_variable *var, struct lower_variables_state *state)
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{
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struct deref_node *node;
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struct hash_entry *var_entry =
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_mesa_hash_table_search(state->deref_var_nodes, var);
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if (var_entry) {
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return var_entry->data;
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} else {
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node = deref_node_create(NULL, var->type, true, state->dead_ctx);
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_mesa_hash_table_insert(state->deref_var_nodes, var, node);
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return node;
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}
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}
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/* Gets the deref_node for the given deref chain and creates it if it
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* doesn't yet exist. If the deref is fully-qualified and direct and
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* state->add_to_direct_deref_nodes is true, it will be added to the hash
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* table of of fully-qualified direct derefs.
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*/
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static struct deref_node *
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get_deref_node_recur(nir_deref_instr *deref,
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struct lower_variables_state *state)
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{
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if (deref->deref_type == nir_deref_type_var)
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return get_deref_node_for_var(deref->var, state);
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if (deref->deref_type == nir_deref_type_cast)
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return NULL;
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struct deref_node *parent =
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get_deref_node_recur(nir_deref_instr_parent(deref), state);
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if (parent == NULL)
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return NULL;
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if (parent == UNDEF_NODE)
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return UNDEF_NODE;
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switch (deref->deref_type) {
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case nir_deref_type_struct:
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assert(glsl_type_is_struct_or_ifc(parent->type));
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assert(deref->strct.index < glsl_get_length(parent->type));
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if (parent->children[deref->strct.index] == NULL) {
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parent->children[deref->strct.index] =
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deref_node_create(parent, deref->type, parent->is_direct,
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state->dead_ctx);
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}
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return parent->children[deref->strct.index];
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case nir_deref_type_array: {
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if (nir_src_is_const(deref->arr.index)) {
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uint32_t index = nir_src_as_uint(deref->arr.index);
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/* This is possible if a loop unrolls and generates an
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* out-of-bounds offset. We need to handle this at least
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* somewhat gracefully.
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*/
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if (index >= glsl_get_length(parent->type))
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return UNDEF_NODE;
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if (parent->children[index] == NULL) {
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parent->children[index] =
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deref_node_create(parent, deref->type, parent->is_direct,
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state->dead_ctx);
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}
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return parent->children[index];
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} else {
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if (parent->indirect == NULL) {
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parent->indirect =
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deref_node_create(parent, deref->type, false, state->dead_ctx);
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}
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return parent->indirect;
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}
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break;
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}
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case nir_deref_type_array_wildcard:
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if (parent->wildcard == NULL) {
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parent->wildcard =
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deref_node_create(parent, deref->type, false, state->dead_ctx);
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}
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return parent->wildcard;
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default:
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unreachable("Invalid deref type");
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}
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}
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static struct deref_node *
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get_deref_node(nir_deref_instr *deref, struct lower_variables_state *state)
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{
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/* This pass only works on local variables. Just ignore any derefs with
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* a non-local mode.
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*/
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if (!nir_deref_mode_must_be(deref, nir_var_function_temp))
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return NULL;
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struct deref_node *node = get_deref_node_recur(deref, state);
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if (!node)
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return NULL;
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/* Insert the node in the direct derefs list. We only do this if it's not
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* already in the list and we only bother for deref nodes which are used
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* directly in a load or store.
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*/
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if (node != UNDEF_NODE && node->is_direct &&
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state->add_to_direct_deref_nodes &&
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node->direct_derefs_link.next == NULL) {
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nir_deref_path_init(&node->path, deref, state->dead_ctx);
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assert(deref->var != NULL);
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exec_list_push_tail(&state->direct_deref_nodes,
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&node->direct_derefs_link);
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}
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return node;
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}
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/* \sa foreach_deref_node_match */
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static void
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foreach_deref_node_worker(struct deref_node *node, nir_deref_instr **path,
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void (* cb)(struct deref_node *node,
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struct lower_variables_state *state),
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struct lower_variables_state *state)
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{
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if (*path == NULL) {
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cb(node, state);
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return;
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}
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switch ((*path)->deref_type) {
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case nir_deref_type_struct:
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if (node->children[(*path)->strct.index]) {
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foreach_deref_node_worker(node->children[(*path)->strct.index],
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path + 1, cb, state);
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}
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return;
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case nir_deref_type_array: {
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uint32_t index = nir_src_as_uint((*path)->arr.index);
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if (node->children[index]) {
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foreach_deref_node_worker(node->children[index],
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path + 1, cb, state);
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}
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if (node->wildcard) {
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foreach_deref_node_worker(node->wildcard,
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path + 1, cb, state);
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}
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return;
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}
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default:
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unreachable("Unsupported deref type");
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}
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}
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/* Walks over every "matching" deref_node and calls the callback. A node
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* is considered to "match" if either refers to that deref or matches up t
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* a wildcard. In other words, the following would match a[6].foo[3].bar:
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*
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* a[6].foo[3].bar
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* a[*].foo[3].bar
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* a[6].foo[*].bar
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* a[*].foo[*].bar
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*
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* The given deref must be a full-length and fully qualified (no wildcards
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* or indirects) deref chain.
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*/
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static void
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foreach_deref_node_match(nir_deref_path *path,
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void (* cb)(struct deref_node *node,
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struct lower_variables_state *state),
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struct lower_variables_state *state)
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{
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assert(path->path[0]->deref_type == nir_deref_type_var);
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struct deref_node *node = get_deref_node_for_var(path->path[0]->var, state);
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if (node == NULL)
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return;
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foreach_deref_node_worker(node, &path->path[1], cb, state);
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}
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/* \sa deref_may_be_aliased */
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static bool
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path_may_be_aliased_node(struct deref_node *node, nir_deref_instr **path,
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struct lower_variables_state *state)
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{
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if (*path == NULL)
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return false;
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switch ((*path)->deref_type) {
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case nir_deref_type_struct:
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if (node->children[(*path)->strct.index]) {
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return path_may_be_aliased_node(node->children[(*path)->strct.index],
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path + 1, state);
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} else {
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return false;
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}
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case nir_deref_type_array: {
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if (!nir_src_is_const((*path)->arr.index))
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return true;
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uint32_t index = nir_src_as_uint((*path)->arr.index);
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/* If there is an indirect at this level, we're aliased. */
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if (node->indirect)
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return true;
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if (node->children[index] &&
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path_may_be_aliased_node(node->children[index],
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path + 1, state))
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return true;
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if (node->wildcard &&
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path_may_be_aliased_node(node->wildcard, path + 1, state))
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return true;
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return false;
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}
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default:
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unreachable("Unsupported deref type");
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}
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}
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/* Returns true if there are no indirects that can ever touch this deref.
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*
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* For example, if the given deref is a[6].foo, then any uses of a[i].foo
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* would cause this to return false, but a[i].bar would not affect it
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* because it's a different structure member. A var_copy involving of
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* a[*].bar also doesn't affect it because that can be lowered to entirely
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* direct load/stores.
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*
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* We only support asking this question about fully-qualified derefs.
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* Obviously, it's pointless to ask this about indirects, but we also
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* rule-out wildcards. Handling Wildcard dereferences would involve
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* checking each array index to make sure that there aren't any indirect
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* references.
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*/
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static bool
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path_may_be_aliased(nir_deref_path *path,
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struct lower_variables_state *state)
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{
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assert(path->path[0]->deref_type == nir_deref_type_var);
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nir_variable *var = path->path[0]->var;
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struct deref_node *var_node = get_deref_node_for_var(var, state);
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/* First see if this variable is ever used by anything other than a
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* load/store. If there's even so much as a cast in the way, we have to
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* assume aliasing and bail.
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*/
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if (var_node->has_complex_use)
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return true;
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return path_may_be_aliased_node(var_node, &path->path[1], state);
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}
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static void
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register_complex_use(nir_deref_instr *deref,
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struct lower_variables_state *state)
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{
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assert(deref->deref_type == nir_deref_type_var);
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struct deref_node *node = get_deref_node_for_var(deref->var, state);
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if (node == NULL)
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return;
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node->has_complex_use = true;
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}
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static void
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register_load_instr(nir_intrinsic_instr *load_instr,
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struct lower_variables_state *state)
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{
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nir_deref_instr *deref = nir_src_as_deref(load_instr->src[0]);
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struct deref_node *node = get_deref_node(deref, state);
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if (node == NULL || node == UNDEF_NODE)
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return;
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if (node->loads == NULL)
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node->loads = _mesa_pointer_set_create(state->dead_ctx);
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_mesa_set_add(node->loads, load_instr);
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}
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static void
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register_store_instr(nir_intrinsic_instr *store_instr,
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struct lower_variables_state *state)
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{
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nir_deref_instr *deref = nir_src_as_deref(store_instr->src[0]);
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struct deref_node *node = get_deref_node(deref, state);
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if (node == NULL || node == UNDEF_NODE)
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return;
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if (node->stores == NULL)
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node->stores = _mesa_pointer_set_create(state->dead_ctx);
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_mesa_set_add(node->stores, store_instr);
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}
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static void
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register_copy_instr(nir_intrinsic_instr *copy_instr,
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struct lower_variables_state *state)
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{
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for (unsigned idx = 0; idx < 2; idx++) {
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nir_deref_instr *deref = nir_src_as_deref(copy_instr->src[idx]);
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struct deref_node *node = get_deref_node(deref, state);
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if (node == NULL || node == UNDEF_NODE)
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continue;
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if (node->copies == NULL)
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node->copies = _mesa_pointer_set_create(state->dead_ctx);
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_mesa_set_add(node->copies, copy_instr);
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}
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}
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static void
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register_variable_uses(nir_function_impl *impl,
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struct lower_variables_state *state)
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{
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nir_foreach_block(block, impl) {
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nir_foreach_instr_safe(instr, block) {
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switch (instr->type) {
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case nir_instr_type_deref: {
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nir_deref_instr *deref = nir_instr_as_deref(instr);
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if (deref->deref_type == nir_deref_type_var &&
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nir_deref_instr_has_complex_use(deref, 0))
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register_complex_use(deref, state);
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break;
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}
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case nir_instr_type_intrinsic: {
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nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
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switch (intrin->intrinsic) {
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case nir_intrinsic_load_deref:
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register_load_instr(intrin, state);
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break;
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case nir_intrinsic_store_deref:
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register_store_instr(intrin, state);
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break;
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case nir_intrinsic_copy_deref:
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register_copy_instr(intrin, state);
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break;
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default:
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continue;
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}
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break;
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}
|
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|
default:
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break;
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}
|
|
}
|
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}
|
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}
|
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|
|
/* Walks over all of the copy instructions to or from the given deref_node
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* and lowers them to load/store intrinsics.
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|
*/
|
|
static void
|
|
lower_copies_to_load_store(struct deref_node *node,
|
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struct lower_variables_state *state)
|
|
{
|
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if (!node->copies)
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return;
|
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|
|
nir_builder b;
|
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nir_builder_init(&b, state->impl);
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|
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set_foreach(node->copies, copy_entry) {
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nir_intrinsic_instr *copy = (void *)copy_entry->key;
|
|
|
|
nir_lower_deref_copy_instr(&b, copy);
|
|
|
|
for (unsigned i = 0; i < 2; ++i) {
|
|
nir_deref_instr *arg_deref = nir_src_as_deref(copy->src[i]);
|
|
struct deref_node *arg_node = get_deref_node(arg_deref, state);
|
|
|
|
/* Only bother removing copy entries for other nodes */
|
|
if (arg_node == NULL || arg_node == node)
|
|
continue;
|
|
|
|
struct set_entry *arg_entry = _mesa_set_search(arg_node->copies, copy);
|
|
assert(arg_entry);
|
|
_mesa_set_remove(arg_node->copies, arg_entry);
|
|
}
|
|
|
|
nir_instr_remove(©->instr);
|
|
}
|
|
|
|
node->copies = NULL;
|
|
}
|
|
|
|
/* Performs variable renaming
|
|
*
|
|
* This algorithm is very similar to the one outlined in "Efficiently
|
|
* Computing Static Single Assignment Form and the Control Dependence
|
|
* Graph" by Cytron et al. The primary difference is that we only put one
|
|
* SSA def on the stack per block.
|
|
*/
|
|
static bool
|
|
rename_variables(struct lower_variables_state *state)
|
|
{
|
|
nir_builder b;
|
|
nir_builder_init(&b, state->impl);
|
|
|
|
nir_foreach_block(block, state->impl) {
|
|
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_must_be(deref, nir_var_function_temp))
|
|
continue;
|
|
|
|
struct deref_node *node = get_deref_node(deref, state);
|
|
if (node == NULL)
|
|
continue;
|
|
|
|
if (node == UNDEF_NODE) {
|
|
/* If we hit this path then we are referencing an invalid
|
|
* value. Most likely, we unrolled something and are
|
|
* reading past the end of some array. In any case, this
|
|
* should result in an undefined value.
|
|
*/
|
|
nir_ssa_undef_instr *undef =
|
|
nir_ssa_undef_instr_create(state->shader,
|
|
intrin->num_components,
|
|
intrin->dest.ssa.bit_size);
|
|
|
|
nir_instr_insert_before(&intrin->instr, &undef->instr);
|
|
nir_instr_remove(&intrin->instr);
|
|
|
|
nir_ssa_def_rewrite_uses(&intrin->dest.ssa,
|
|
&undef->def);
|
|
continue;
|
|
}
|
|
|
|
if (!node->lower_to_ssa)
|
|
continue;
|
|
|
|
nir_alu_instr *mov = nir_alu_instr_create(state->shader,
|
|
nir_op_mov);
|
|
mov->src[0].src = nir_src_for_ssa(
|
|
nir_phi_builder_value_get_block_def(node->pb_value, block));
|
|
for (unsigned i = intrin->num_components; i < NIR_MAX_VEC_COMPONENTS; i++)
|
|
mov->src[0].swizzle[i] = 0;
|
|
|
|
assert(intrin->dest.is_ssa);
|
|
|
|
mov->dest.write_mask = (1 << intrin->num_components) - 1;
|
|
nir_ssa_dest_init(&mov->instr, &mov->dest.dest,
|
|
intrin->num_components,
|
|
intrin->dest.ssa.bit_size, NULL);
|
|
|
|
nir_instr_insert_before(&intrin->instr, &mov->instr);
|
|
nir_instr_remove(&intrin->instr);
|
|
|
|
nir_ssa_def_rewrite_uses(&intrin->dest.ssa,
|
|
&mov->dest.dest.ssa);
|
|
break;
|
|
}
|
|
|
|
case nir_intrinsic_store_deref: {
|
|
nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]);
|
|
if (!nir_deref_mode_must_be(deref, nir_var_function_temp))
|
|
continue;
|
|
|
|
struct deref_node *node = get_deref_node(deref, state);
|
|
if (node == NULL)
|
|
continue;
|
|
|
|
assert(intrin->src[1].is_ssa);
|
|
nir_ssa_def *value = intrin->src[1].ssa;
|
|
|
|
if (node == UNDEF_NODE) {
|
|
/* Probably an out-of-bounds array store. That should be a
|
|
* no-op. */
|
|
nir_instr_remove(&intrin->instr);
|
|
continue;
|
|
}
|
|
|
|
if (!node->lower_to_ssa)
|
|
continue;
|
|
|
|
assert(intrin->num_components ==
|
|
glsl_get_vector_elements(node->type));
|
|
|
|
nir_ssa_def *new_def;
|
|
b.cursor = nir_before_instr(&intrin->instr);
|
|
|
|
unsigned wrmask = nir_intrinsic_write_mask(intrin);
|
|
if (wrmask == (1 << intrin->num_components) - 1) {
|
|
/* Whole variable store - just copy the source. Note that
|
|
* intrin->num_components and value->num_components
|
|
* may differ.
|
|
*/
|
|
unsigned swiz[NIR_MAX_VEC_COMPONENTS];
|
|
for (unsigned i = 0; i < NIR_MAX_VEC_COMPONENTS; i++)
|
|
swiz[i] = i < intrin->num_components ? i : 0;
|
|
|
|
new_def = nir_swizzle(&b, value, swiz,
|
|
intrin->num_components);
|
|
} else {
|
|
nir_ssa_def *old_def =
|
|
nir_phi_builder_value_get_block_def(node->pb_value, block);
|
|
/* For writemasked store_var intrinsics, we combine the newly
|
|
* written values with the existing contents of unwritten
|
|
* channels, creating a new SSA value for the whole vector.
|
|
*/
|
|
nir_ssa_scalar srcs[NIR_MAX_VEC_COMPONENTS];
|
|
for (unsigned i = 0; i < intrin->num_components; i++) {
|
|
if (wrmask & (1 << i)) {
|
|
srcs[i] = nir_get_ssa_scalar(value, i);
|
|
} else {
|
|
srcs[i] = nir_get_ssa_scalar(old_def, i);
|
|
}
|
|
}
|
|
new_def = nir_vec_scalars(&b, srcs, intrin->num_components);
|
|
}
|
|
|
|
assert(new_def->num_components == intrin->num_components);
|
|
|
|
nir_phi_builder_value_set_block_def(node->pb_value, block, new_def);
|
|
nir_instr_remove(&intrin->instr);
|
|
break;
|
|
}
|
|
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/** Implements a pass to lower variable uses to SSA values
|
|
*
|
|
* This path walks the list of instructions and tries to lower as many
|
|
* local variable load/store operations to SSA defs and uses as it can.
|
|
* The process involves four passes:
|
|
*
|
|
* 1) Iterate over all of the instructions and mark where each local
|
|
* variable deref is used in a load, store, or copy. While we're at
|
|
* it, we keep track of all of the fully-qualified (no wildcards) and
|
|
* fully-direct references we see and store them in the
|
|
* direct_deref_nodes hash table.
|
|
*
|
|
* 2) Walk over the list of fully-qualified direct derefs generated in
|
|
* the previous pass. For each deref, we determine if it can ever be
|
|
* aliased, i.e. if there is an indirect reference anywhere that may
|
|
* refer to it. If it cannot be aliased, we mark it for lowering to an
|
|
* SSA value. At this point, we lower any var_copy instructions that
|
|
* use the given deref to load/store operations.
|
|
*
|
|
* 3) Walk over the list of derefs we plan to lower to SSA values and
|
|
* insert phi nodes as needed.
|
|
*
|
|
* 4) Perform "variable renaming" by replacing the load/store instructions
|
|
* with SSA definitions and SSA uses.
|
|
*/
|
|
static bool
|
|
nir_lower_vars_to_ssa_impl(nir_function_impl *impl)
|
|
{
|
|
struct lower_variables_state state;
|
|
|
|
state.shader = impl->function->shader;
|
|
state.dead_ctx = ralloc_context(state.shader);
|
|
state.impl = impl;
|
|
|
|
state.deref_var_nodes = _mesa_pointer_hash_table_create(state.dead_ctx);
|
|
exec_list_make_empty(&state.direct_deref_nodes);
|
|
|
|
/* Build the initial deref structures and direct_deref_nodes table */
|
|
state.add_to_direct_deref_nodes = true;
|
|
|
|
register_variable_uses(impl, &state);
|
|
|
|
bool progress = false;
|
|
|
|
nir_metadata_require(impl, nir_metadata_block_index);
|
|
|
|
/* We're about to iterate through direct_deref_nodes. Don't modify it. */
|
|
state.add_to_direct_deref_nodes = false;
|
|
|
|
foreach_list_typed_safe(struct deref_node, node, direct_derefs_link,
|
|
&state.direct_deref_nodes) {
|
|
nir_deref_path *path = &node->path;
|
|
|
|
assert(path->path[0]->deref_type == nir_deref_type_var);
|
|
|
|
/* We don't build deref nodes for non-local variables */
|
|
assert(path->path[0]->var->data.mode == nir_var_function_temp);
|
|
|
|
if (path_may_be_aliased(path, &state)) {
|
|
exec_node_remove(&node->direct_derefs_link);
|
|
continue;
|
|
}
|
|
|
|
node->lower_to_ssa = true;
|
|
progress = true;
|
|
|
|
foreach_deref_node_match(path, lower_copies_to_load_store, &state);
|
|
}
|
|
|
|
if (!progress) {
|
|
nir_metadata_preserve(impl, nir_metadata_all);
|
|
return false;
|
|
}
|
|
|
|
nir_metadata_require(impl, nir_metadata_dominance);
|
|
|
|
/* We may have lowered some copy instructions to load/store
|
|
* instructions. The uses from the copy instructions hav already been
|
|
* removed but we need to rescan to ensure that the uses from the newly
|
|
* added load/store instructions are registered. We need this
|
|
* information for phi node insertion below.
|
|
*/
|
|
register_variable_uses(impl, &state);
|
|
|
|
state.phi_builder = nir_phi_builder_create(state.impl);
|
|
|
|
BITSET_WORD *store_blocks =
|
|
ralloc_array(state.dead_ctx, BITSET_WORD,
|
|
BITSET_WORDS(state.impl->num_blocks));
|
|
foreach_list_typed(struct deref_node, node, direct_derefs_link,
|
|
&state.direct_deref_nodes) {
|
|
if (!node->lower_to_ssa)
|
|
continue;
|
|
|
|
memset(store_blocks, 0,
|
|
BITSET_WORDS(state.impl->num_blocks) * sizeof(*store_blocks));
|
|
|
|
assert(node->path.path[0]->var->constant_initializer == NULL &&
|
|
node->path.path[0]->var->pointer_initializer == NULL);
|
|
|
|
if (node->stores) {
|
|
set_foreach(node->stores, store_entry) {
|
|
nir_intrinsic_instr *store =
|
|
(nir_intrinsic_instr *)store_entry->key;
|
|
BITSET_SET(store_blocks, store->instr.block->index);
|
|
}
|
|
}
|
|
|
|
node->pb_value =
|
|
nir_phi_builder_add_value(state.phi_builder,
|
|
glsl_get_vector_elements(node->type),
|
|
glsl_get_bit_size(node->type),
|
|
store_blocks);
|
|
}
|
|
|
|
rename_variables(&state);
|
|
|
|
nir_phi_builder_finish(state.phi_builder);
|
|
|
|
nir_metadata_preserve(impl, nir_metadata_block_index |
|
|
nir_metadata_dominance);
|
|
|
|
ralloc_free(state.dead_ctx);
|
|
|
|
return progress;
|
|
}
|
|
|
|
bool
|
|
nir_lower_vars_to_ssa(nir_shader *shader)
|
|
{
|
|
bool progress = false;
|
|
|
|
nir_foreach_function(function, shader) {
|
|
if (function->impl)
|
|
progress |= nir_lower_vars_to_ssa_impl(function->impl);
|
|
}
|
|
|
|
return progress;
|
|
}
|