+++ /dev/null
-/*
- * Copyright © 2014 Broadcom
- *
- * 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 vc4_opt_cse.c
- *
- * Implements CSE for QIR without control flow.
- *
- * For each operation that writes a destination (and isn't just a MOV), put it
- * in the hash table of all instructions that do so. When faced with another
- * one, look it up in the hash table by its opcode and operands. If there's
- * an entry in the table, then just reuse the entry's destination as the
- * source of a MOV instead of reproducing the computation. That MOV will then
- * get cleaned up by copy propagation.
- */
-
-#include "vc4_qir.h"
-
-#include "util/hash_table.h"
-#include "util/ralloc.h"
-
-static bool debug;
-
-struct inst_key {
- enum qop op;
- struct qreg src[4];
- /**
- * If the instruction depends on the flags, how many SFs have been
- * seen before this instruction.
- */
- uint32_t implicit_arg_update_count;
-};
-
-static bool
-inst_key_equals(const void *a, const void *b)
-{
- const struct inst_key *key_a = a;
- const struct inst_key *key_b = b;
-
- return memcmp(key_a, key_b, sizeof(*key_a)) == 0;
-}
-
-static struct qinst *
-vc4_find_cse(struct vc4_compile *c, struct hash_table *ht,
- struct qinst *inst, uint32_t sf_count)
-{
- if (inst->dst.file != QFILE_TEMP ||
- !c->defs[inst->dst.index] ||
- inst->op == QOP_MOV ||
- qir_get_op_nsrc(inst->op) > 4) {
- return NULL;
- }
-
- struct inst_key key;
- memset(&key, 0, sizeof(key));
- key.op = inst->op;
- memcpy(key.src, inst->src,
- qir_get_op_nsrc(inst->op) * sizeof(key.src[0]));
- if (qir_depends_on_flags(inst))
- key.implicit_arg_update_count = sf_count;
-
- uint32_t hash = _mesa_hash_data(&key, sizeof(key));
- struct hash_entry *entry =
- _mesa_hash_table_search_pre_hashed(ht, hash, &key);
-
- if (entry) {
- if (debug) {
- fprintf(stderr, "CSE found match:\n");
-
- fprintf(stderr, " Original inst: ");
- qir_dump_inst(c, entry->data);
- fprintf(stderr, "\n");
-
- fprintf(stderr, " Our inst: ");
- qir_dump_inst(c, inst);
- fprintf(stderr, "\n");
- }
-
- return entry->data;
- }
-
- struct inst_key *alloc_key = ralloc(ht, struct inst_key);
- if (!alloc_key)
- return NULL;
- memcpy(alloc_key, &key, sizeof(*alloc_key));
- _mesa_hash_table_insert_pre_hashed(ht, hash, alloc_key, inst);
-
- if (debug) {
- fprintf(stderr, "Added to CSE HT: ");
- qir_dump_inst(c, inst);
- fprintf(stderr, "\n");
- }
-
- return NULL;
-}
-
-bool
-qir_opt_cse(struct vc4_compile *c)
-{
- bool progress = false;
- uint32_t sf_count = 0;
-
- struct hash_table *ht = _mesa_hash_table_create(NULL, NULL,
- inst_key_equals);
- if (!ht)
- return false;
-
- list_for_each_entry(struct qinst, inst, &c->instructions, link) {
- if (qir_has_side_effects(c, inst) ||
- qir_has_side_effect_reads(c, inst) ||
- inst->op == QOP_TLB_COLOR_READ) {
- continue;
- }
-
- if (inst->sf) {
- sf_count++;
- } else {
- struct qinst *cse = vc4_find_cse(c, ht, inst, sf_count);
- if (cse) {
- inst->src[0] = cse->dst;
- for (int i = 1; i < qir_get_op_nsrc(inst->op);
- i++)
- inst->src[i] = c->undef;
- inst->op = QOP_MOV;
- progress = true;
-
- if (debug) {
- fprintf(stderr, " Turned into: ");
- qir_dump_inst(c, inst);
- fprintf(stderr, "\n");
- }
- }
- }
- }
-
- ralloc_free(ht);
-
- return progress;
-}
projects / mesa.git / commitdiff