diff options
Diffstat (limited to 'src/broadcom/compiler/vir_lower_uniforms.c')
| -rw-r--r-- | src/broadcom/compiler/vir_lower_uniforms.c | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/src/broadcom/compiler/vir_lower_uniforms.c b/src/broadcom/compiler/vir_lower_uniforms.c new file mode 100644 index 00000000000..b2741994a2d --- /dev/null +++ b/src/broadcom/compiler/vir_lower_uniforms.c @@ -0,0 +1,209 @@ +/* + * 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 v3d_vir_lower_uniforms.c + * + * This is the pre-code-generation pass for fixing up instructions that try to + * read from multiple uniform values. + */ + +#include "v3d_compiler.h" +#include "util/hash_table.h" +#include "util/u_math.h" + +static inline uint32_t +index_hash(const void *key) +{ + return (uintptr_t)key; +} + +static inline bool +index_compare(const void *a, const void *b) +{ + return a == b; +} + +static void +add_uniform(struct hash_table *ht, struct qreg reg) +{ + struct hash_entry *entry; + void *key = (void *)(uintptr_t)(reg.index + 1); + + entry = _mesa_hash_table_search(ht, key); + if (entry) { + entry->data++; + } else { + _mesa_hash_table_insert(ht, key, (void *)(uintptr_t)1); + } +} + +static void +remove_uniform(struct hash_table *ht, struct qreg reg) +{ + struct hash_entry *entry; + void *key = (void *)(uintptr_t)(reg.index + 1); + + entry = _mesa_hash_table_search(ht, key); + assert(entry); + entry->data--; + if (entry->data == NULL) + _mesa_hash_table_remove(ht, entry); +} + +static bool +is_lowerable_uniform(struct qinst *inst, int i) +{ + if (inst->src[i].file != QFILE_UNIF) + return false; + if (vir_has_implicit_uniform(inst)) + return i != vir_get_implicit_uniform_src(inst); + return true; +} + +/* Returns the number of different uniform values referenced by the + * instruction. + */ +static uint32_t +vir_get_instruction_uniform_count(struct qinst *inst) +{ + uint32_t count = 0; + + for (int i = 0; i < vir_get_nsrc(inst); i++) { + if (inst->src[i].file != QFILE_UNIF) + continue; + + bool is_duplicate = false; + for (int j = 0; j < i; j++) { + if (inst->src[j].file == QFILE_UNIF && + inst->src[j].index == inst->src[i].index) { + is_duplicate = true; + break; + } + } + if (!is_duplicate) + count++; + } + + return count; +} + +void +vir_lower_uniforms(struct v3d_compile *c) +{ + struct hash_table *ht = + _mesa_hash_table_create(c, index_hash, index_compare); + + /* Walk the instruction list, finding which instructions have more + * than one uniform referenced, and add those uniform values to the + * ht. + */ + vir_for_each_inst_inorder(inst, c) { + uint32_t nsrc = vir_get_nsrc(inst); + + if (vir_get_instruction_uniform_count(inst) <= 1) + continue; + + for (int i = 0; i < nsrc; i++) { + if (is_lowerable_uniform(inst, i)) + add_uniform(ht, inst->src[i]); + } + } + + while (ht->entries) { + /* Find the most commonly used uniform in instructions that + * need a uniform lowered. + */ + uint32_t max_count = 0; + uint32_t max_index = 0; + struct hash_entry *entry; + hash_table_foreach(ht, entry) { + uint32_t count = (uintptr_t)entry->data; + uint32_t index = (uintptr_t)entry->key - 1; + if (count > max_count) { + max_count = count; + max_index = index; + } + } + + struct qreg unif = vir_reg(QFILE_UNIF, max_index); + + /* Now, find the instructions using this uniform and make them + * reference a temp instead. + */ + vir_for_each_block(block, c) { + struct qinst *mov = NULL; + + vir_for_each_inst(inst, block) { + uint32_t nsrc = vir_get_nsrc(inst); + + uint32_t count = vir_get_instruction_uniform_count(inst); + + if (count <= 1) + continue; + + /* If the block doesn't have a load of the + * uniform yet, add it. We could potentially + * do better and CSE MOVs from multiple blocks + * into dominating blocks, except that may + * cause troubles for register allocation. + */ + if (!mov) { + mov = vir_mul_inst(V3D_QPU_M_MOV, + vir_get_temp(c), + unif, c->undef); + list_add(&mov->link, + &block->instructions); + c->defs[mov->dst.index] = mov; + } + + bool removed = false; + for (int i = 0; i < nsrc; i++) { + if (is_lowerable_uniform(inst, i) && + inst->src[i].index == max_index) { + inst->src[i].file = + mov->dst.file; + inst->src[i].index = + mov->dst.index; + remove_uniform(ht, unif); + removed = true; + } + } + if (removed) + count--; + + /* If the instruction doesn't need lowering any more, + * then drop it from the list. + */ + if (count <= 1) { + for (int i = 0; i < nsrc; i++) { + if (is_lowerable_uniform(inst, i)) + remove_uniform(ht, inst->src[i]); + } + } + } + } + } + + _mesa_hash_table_destroy(ht, NULL); +} |