From 378f9967710e9145f2a4f8eee89d87badbe0e6ea Mon Sep 17 00:00:00 2001 From: Ian Romanick Date: Mon, 18 Jun 2018 16:11:55 -0700 Subject: [PATCH] nir/opt_peephole_select: Don't peephole_select expensive math instructions On some GPUs, especially older Intel GPUs, some math instructions are very expensive. On those architectures, don't reduce flow control to a csel if one of the branches contains one of these expensive math instructions. This prevents a bunch of cycle count regressions on pre-Gen6 platforms with a later patch (intel/compiler: More peephole select for pre-Gen6). v2: Remove stray #if block. Noticed by Thomas. Signed-off-by: Ian Romanick Reviewed-by: Thomas Helland Reviewed-by: Lionel Landwerlin --- src/amd/vulkan/radv_shader.c | 2 +- src/broadcom/compiler/nir_to_vir.c | 2 +- src/compiler/nir/nir.h | 2 +- src/compiler/nir/nir_opt_peephole_select.c | 39 ++++++++++++++++---- src/freedreno/ir3/ir3_nir.c | 2 +- src/gallium/drivers/radeonsi/si_shader_nir.c | 2 +- src/gallium/drivers/vc4/vc4_program.c | 2 +- src/intel/compiler/brw_nir.c | 4 +- src/mesa/state_tracker/st_glsl_to_nir.cpp | 2 +- 9 files changed, 40 insertions(+), 17 deletions(-) diff --git a/src/amd/vulkan/radv_shader.c b/src/amd/vulkan/radv_shader.c index f778e85b8d9..2eb5164ac97 100644 --- a/src/amd/vulkan/radv_shader.c +++ b/src/amd/vulkan/radv_shader.c @@ -159,7 +159,7 @@ radv_optimize_nir(struct nir_shader *shader, bool optimize_conservatively, NIR_PASS(progress, shader, nir_opt_if); NIR_PASS(progress, shader, nir_opt_dead_cf); NIR_PASS(progress, shader, nir_opt_cse); - NIR_PASS(progress, shader, nir_opt_peephole_select, 8, true); + NIR_PASS(progress, shader, nir_opt_peephole_select, 8, true, true); NIR_PASS(progress, shader, nir_opt_algebraic); NIR_PASS(progress, shader, nir_opt_constant_folding); NIR_PASS(progress, shader, nir_opt_undef); diff --git a/src/broadcom/compiler/nir_to_vir.c b/src/broadcom/compiler/nir_to_vir.c index 9b1066467cc..ada0dd69921 100644 --- a/src/broadcom/compiler/nir_to_vir.c +++ b/src/broadcom/compiler/nir_to_vir.c @@ -1241,7 +1241,7 @@ v3d_optimize_nir(struct nir_shader *s) NIR_PASS(progress, s, nir_opt_dce); NIR_PASS(progress, s, nir_opt_dead_cf); NIR_PASS(progress, s, nir_opt_cse); - NIR_PASS(progress, s, nir_opt_peephole_select, 8, true); + NIR_PASS(progress, s, nir_opt_peephole_select, 8, true, true); NIR_PASS(progress, s, nir_opt_algebraic); NIR_PASS(progress, s, nir_opt_constant_folding); NIR_PASS(progress, s, nir_opt_undef); diff --git a/src/compiler/nir/nir.h b/src/compiler/nir/nir.h index 2bbfb3c6b15..54f9c64a3a3 100644 --- a/src/compiler/nir/nir.h +++ b/src/compiler/nir/nir.h @@ -3198,7 +3198,7 @@ bool nir_opt_move_comparisons(nir_shader *shader); bool nir_opt_move_load_ubo(nir_shader *shader); bool nir_opt_peephole_select(nir_shader *shader, unsigned limit, - bool indirect_load_ok); + bool indirect_load_ok, bool expensive_alu_ok); bool nir_opt_remove_phis_impl(nir_function_impl *impl); bool nir_opt_remove_phis(nir_shader *shader); diff --git a/src/compiler/nir/nir_opt_peephole_select.c b/src/compiler/nir/nir_opt_peephole_select.c index 6808d3eda6c..b27cdd28a99 100644 --- a/src/compiler/nir/nir_opt_peephole_select.c +++ b/src/compiler/nir/nir_opt_peephole_select.c @@ -59,7 +59,8 @@ static bool block_check_for_allowed_instrs(nir_block *block, unsigned *count, - bool alu_ok, bool indirect_load_ok) + bool alu_ok, bool indirect_load_ok, + bool expensive_alu_ok) { nir_foreach_instr(instr, block) { switch (instr->type) { @@ -117,6 +118,25 @@ block_check_for_allowed_instrs(nir_block *block, unsigned *count, case nir_op_vec3: case nir_op_vec4: break; + + case nir_op_fcos: + case nir_op_fdiv: + case nir_op_fexp2: + case nir_op_flog2: + case nir_op_fmod: + case nir_op_fpow: + case nir_op_frcp: + case nir_op_frem: + case nir_op_frsq: + case nir_op_fsin: + case nir_op_idiv: + case nir_op_irem: + case nir_op_udiv: + if (!alu_ok || !expensive_alu_ok) + return false; + + break; + default: if (!alu_ok) { /* It must be a move-like operation. */ @@ -160,7 +180,8 @@ block_check_for_allowed_instrs(nir_block *block, unsigned *count, static bool nir_opt_peephole_select_block(nir_block *block, nir_shader *shader, - unsigned limit, bool indirect_load_ok) + unsigned limit, bool indirect_load_ok, + bool expensive_alu_ok) { if (nir_cf_node_is_first(&block->cf_node)) return false; @@ -181,9 +202,9 @@ nir_opt_peephole_select_block(nir_block *block, nir_shader *shader, /* ... and those blocks must only contain "allowed" instructions. */ unsigned count = 0; if (!block_check_for_allowed_instrs(then_block, &count, limit != 0, - indirect_load_ok) || + indirect_load_ok, expensive_alu_ok) || !block_check_for_allowed_instrs(else_block, &count, limit != 0, - indirect_load_ok)) + indirect_load_ok, expensive_alu_ok)) return false; if (count > limit) @@ -250,14 +271,15 @@ nir_opt_peephole_select_block(nir_block *block, nir_shader *shader, static bool nir_opt_peephole_select_impl(nir_function_impl *impl, unsigned limit, - bool indirect_load_ok) + bool indirect_load_ok, bool expensive_alu_ok) { nir_shader *shader = impl->function->shader; bool progress = false; nir_foreach_block_safe(block, impl) { progress |= nir_opt_peephole_select_block(block, shader, limit, - indirect_load_ok); + indirect_load_ok, + expensive_alu_ok); } if (progress) @@ -268,14 +290,15 @@ nir_opt_peephole_select_impl(nir_function_impl *impl, unsigned limit, bool nir_opt_peephole_select(nir_shader *shader, unsigned limit, - bool indirect_load_ok) + bool indirect_load_ok, bool expensive_alu_ok) { bool progress = false; nir_foreach_function(function, shader) { if (function->impl) progress |= nir_opt_peephole_select_impl(function->impl, limit, - indirect_load_ok); + indirect_load_ok, + expensive_alu_ok); } return progress; diff --git a/src/freedreno/ir3/ir3_nir.c b/src/freedreno/ir3/ir3_nir.c index 112c0928529..f5db5d151ef 100644 --- a/src/freedreno/ir3/ir3_nir.c +++ b/src/freedreno/ir3/ir3_nir.c @@ -97,7 +97,7 @@ ir3_optimize_loop(nir_shader *s) progress |= OPT(s, nir_opt_gcm, true); else if (gcm == 2) progress |= OPT(s, nir_opt_gcm, false); - progress |= OPT(s, nir_opt_peephole_select, 16, true); + progress |= OPT(s, nir_opt_peephole_select, 16, true, true); progress |= OPT(s, nir_opt_intrinsics); progress |= OPT(s, nir_opt_algebraic); progress |= OPT(s, nir_opt_constant_folding); diff --git a/src/gallium/drivers/radeonsi/si_shader_nir.c b/src/gallium/drivers/radeonsi/si_shader_nir.c index 89acaab248a..0a692277f64 100644 --- a/src/gallium/drivers/radeonsi/si_shader_nir.c +++ b/src/gallium/drivers/radeonsi/si_shader_nir.c @@ -841,7 +841,7 @@ si_lower_nir(struct si_shader_selector* sel) NIR_PASS(progress, sel->nir, nir_opt_if); NIR_PASS(progress, sel->nir, nir_opt_dead_cf); NIR_PASS(progress, sel->nir, nir_opt_cse); - NIR_PASS(progress, sel->nir, nir_opt_peephole_select, 8, true); + NIR_PASS(progress, sel->nir, nir_opt_peephole_select, 8, true, true); /* Needed for algebraic lowering */ NIR_PASS(progress, sel->nir, nir_opt_algebraic); diff --git a/src/gallium/drivers/vc4/vc4_program.c b/src/gallium/drivers/vc4/vc4_program.c index 48d83061f9a..fb75c07e266 100644 --- a/src/gallium/drivers/vc4/vc4_program.c +++ b/src/gallium/drivers/vc4/vc4_program.c @@ -1591,7 +1591,7 @@ vc4_optimize_nir(struct nir_shader *s) NIR_PASS(progress, s, nir_opt_dce); NIR_PASS(progress, s, nir_opt_dead_cf); NIR_PASS(progress, s, nir_opt_cse); - NIR_PASS(progress, s, nir_opt_peephole_select, 8, true); + NIR_PASS(progress, s, nir_opt_peephole_select, 8, true, true); NIR_PASS(progress, s, nir_opt_algebraic); NIR_PASS(progress, s, nir_opt_constant_folding); NIR_PASS(progress, s, nir_opt_undef); diff --git a/src/intel/compiler/brw_nir.c b/src/intel/compiler/brw_nir.c index 3e547daf78a..8a5665076b9 100644 --- a/src/intel/compiler/brw_nir.c +++ b/src/intel/compiler/brw_nir.c @@ -589,9 +589,9 @@ brw_nir_optimize(nir_shader *nir, const struct brw_compiler *compiler, const bool is_vec4_tessellation = !is_scalar && (nir->info.stage == MESA_SHADER_TESS_CTRL || nir->info.stage == MESA_SHADER_TESS_EVAL); - OPT(nir_opt_peephole_select, 0, !is_vec4_tessellation); + OPT(nir_opt_peephole_select, 0, !is_vec4_tessellation, false); if (compiler->devinfo->gen >= 6) - OPT(nir_opt_peephole_select, 1, !is_vec4_tessellation); + OPT(nir_opt_peephole_select, 1, !is_vec4_tessellation, true); OPT(nir_opt_intrinsics); OPT(nir_opt_idiv_const, 32); diff --git a/src/mesa/state_tracker/st_glsl_to_nir.cpp b/src/mesa/state_tracker/st_glsl_to_nir.cpp index e6d5c86bfbc..ed9f643e890 100644 --- a/src/mesa/state_tracker/st_glsl_to_nir.cpp +++ b/src/mesa/state_tracker/st_glsl_to_nir.cpp @@ -328,7 +328,7 @@ st_nir_opts(nir_shader *nir, bool scalar) NIR_PASS(progress, nir, nir_opt_if); NIR_PASS(progress, nir, nir_opt_dead_cf); NIR_PASS(progress, nir, nir_opt_cse); - NIR_PASS(progress, nir, nir_opt_peephole_select, 8, true); + NIR_PASS(progress, nir, nir_opt_peephole_select, 8, true, true); NIR_PASS(progress, nir, nir_opt_algebraic); NIR_PASS(progress, nir, nir_opt_constant_folding); -- 2.30.2