From 58f91718944a0cabdd907ed87efe7a239e69a55d Mon Sep 17 00:00:00 2001 From: Alyssa Rosenzweig Date: Wed, 11 Mar 2020 15:10:32 -0400 Subject: [PATCH] pan/bi: Add dead code elimination pass Now that we have liveness analysis, we can cleanup the IR considerably. Signed-off-by: Alyssa Rosenzweig Part-of: --- src/panfrost/bifrost/bi_opt_dce.c | 53 ++++++++++++++++++++++++++ src/panfrost/bifrost/bifrost_compile.c | 11 ++++++ src/panfrost/bifrost/compiler.h | 3 +- src/panfrost/bifrost/meson.build | 1 + 4 files changed, 67 insertions(+), 1 deletion(-) create mode 100644 src/panfrost/bifrost/bi_opt_dce.c diff --git a/src/panfrost/bifrost/bi_opt_dce.c b/src/panfrost/bifrost/bi_opt_dce.c new file mode 100644 index 00000000000..9a0c0396ad7 --- /dev/null +++ b/src/panfrost/bifrost/bi_opt_dce.c @@ -0,0 +1,53 @@ +/* + * Copyright (C) 2018 Alyssa Rosenzweig + * Copyright (C) 2019-2020 Collabora, Ltd. + * + * 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 "compiler.h" +#include "util/u_memory.h" + +bool +bi_opt_dead_code_eliminate(bi_context *ctx, bi_block *block) +{ + bool progress = false; + unsigned temp_count = bi_max_temp(ctx); + + bi_invalidate_liveness(ctx); + bi_compute_liveness(ctx); + + uint16_t *live = mem_dup(block->base.live_out, temp_count * sizeof(uint16_t)); + + bi_foreach_instr_in_block_safe_rev(block, ins) { + if (ins->dest && !(ins->dest & BIR_SPECIAL)) { + if (!live[ins->dest]) { + bi_remove_instruction(ins); + progress |= true; + } + } + + bi_liveness_ins_update(live, ins, temp_count); + } + + free(live); + + return progress; +} diff --git a/src/panfrost/bifrost/bifrost_compile.c b/src/panfrost/bifrost/bifrost_compile.c index 6893bfcf5b1..8e02437df52 100644 --- a/src/panfrost/bifrost/bifrost_compile.c +++ b/src/panfrost/bifrost/bifrost_compile.c @@ -841,6 +841,17 @@ bifrost_compile_shader_nir(nir_shader *nir, panfrost_program *program, unsigned break; /* TODO: Multi-function shaders */ } + bool progress = false; + + do { + progress = false; + + bi_foreach_block(ctx, _block) { + bi_block *block = (bi_block *) _block; + progress |= bi_opt_dead_code_eliminate(ctx, block); + } + } while(progress); + bi_print_shader(ctx, stdout); bi_schedule(ctx); diff --git a/src/panfrost/bifrost/compiler.h b/src/panfrost/bifrost/compiler.h index cc00c7f69ef..57ffdf2a8e0 100644 --- a/src/panfrost/bifrost/compiler.h +++ b/src/panfrost/bifrost/compiler.h @@ -378,7 +378,7 @@ bi_remove_instruction(bi_instruction *ins) /* Keep me synced please so we can check src & BIR_SPECIAL */ #define BIR_SPECIAL ((BIR_INDEX_REGISTER | BIR_INDEX_UNIFORM) | \ - (BIR_INDEX_CONSTANT | BIR_INDEX_ZERO) + (BIR_INDEX_CONSTANT | BIR_INDEX_ZERO)) static inline unsigned bi_max_temp(bi_context *ctx) @@ -501,6 +501,7 @@ uint16_t bi_bytemask_of_read_components(bi_instruction *ins, unsigned node); /* BIR passes */ +bool bi_opt_dead_code_eliminate(bi_context *ctx, bi_block *block); void bi_schedule(bi_context *ctx); /* Liveness */ diff --git a/src/panfrost/bifrost/meson.build b/src/panfrost/bifrost/meson.build index 1033318508e..fac47e02981 100644 --- a/src/panfrost/bifrost/meson.build +++ b/src/panfrost/bifrost/meson.build @@ -23,6 +23,7 @@ libpanfrost_bifrost_files = files( 'disassemble.c', 'bi_liveness.c', 'bi_print.c', + 'bi_opt_dce.c', 'bi_schedule.c', 'bi_tables.c', 'bir.c', -- 2.30.2