From 5854d4583c6e8885185e12a0636f77489a62e24c Mon Sep 17 00:00:00 2001 From: Eric Anholt Date: Mon, 9 Aug 2010 21:22:17 -0700 Subject: [PATCH] glsl2: Add a pass to transform ir_binop_sub to add(op0, neg(op1)) All the current HW backends transform subtract to adding the negation, so I haven't bothered peepholing it back out in Mesa IR. This allows some subtract of subtract to get removed in ir_algebraic. --- src/glsl/Makefile | 1 + src/glsl/ir_optimization.h | 1 + src/glsl/ir_sub_to_add_neg.cpp | 76 +++++++++++++++++++++++++++++++++ src/glsl/linker.cpp | 1 + src/mesa/program/ir_to_mesa.cpp | 1 + 5 files changed, 80 insertions(+) create mode 100644 src/glsl/ir_sub_to_add_neg.cpp diff --git a/src/glsl/Makefile b/src/glsl/Makefile index 841e2b9ce9c..85298d06a01 100644 --- a/src/glsl/Makefile +++ b/src/glsl/Makefile @@ -59,6 +59,7 @@ CXX_SOURCES = \ ir_reader.cpp \ ir_set_program_inouts.cpp \ ir_structure_splitting.cpp \ + ir_sub_to_add_neg.cpp \ ir_swizzle_swizzle.cpp \ ir_tree_grafting.cpp \ ir_validate.cpp \ diff --git a/src/glsl/ir_optimization.h b/src/glsl/ir_optimization.h index 97a0c25216e..5997a30eab3 100644 --- a/src/glsl/ir_optimization.h +++ b/src/glsl/ir_optimization.h @@ -47,6 +47,7 @@ bool do_if_to_cond_assign(exec_list *instructions); bool do_mat_op_to_vec(exec_list *instructions); bool do_mod_to_fract(exec_list *instructions); bool do_structure_splitting(exec_list *instructions); +bool do_sub_to_add_neg(exec_list *instructions); bool do_swizzle_swizzle(exec_list *instructions); bool do_tree_grafting(exec_list *instructions); bool do_vec_index_to_cond_assign(exec_list *instructions); diff --git a/src/glsl/ir_sub_to_add_neg.cpp b/src/glsl/ir_sub_to_add_neg.cpp new file mode 100644 index 00000000000..7ed8c1495e3 --- /dev/null +++ b/src/glsl/ir_sub_to_add_neg.cpp @@ -0,0 +1,76 @@ +/* + * Copyright © 2010 Intel Corporation + * + * 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 ir_sub_to_add_neg.cpp + * + * Breaks an ir_binop_sub expression down to add(op0, neg(op1)) + * + * This simplifies expression reassociation, and for many backends + * there is no subtract operation separate from adding the negation. + * For backends with native subtract operations, they will probably + * want to recognize add(op0, neg(op1)) or the other way around to + * produce a subtract anyway. + */ + +#include "ir.h" + +class ir_sub_to_add_neg_visitor : public ir_hierarchical_visitor { +public: + ir_sub_to_add_neg_visitor() + { + this->progress = false; + } + + ir_visitor_status visit_leave(ir_expression *); + + bool progress; +}; + +bool +do_sub_to_add_neg(exec_list *instructions) +{ + ir_sub_to_add_neg_visitor v; + + visit_list_elements(&v, instructions); + return v.progress; +} + +ir_visitor_status +ir_sub_to_add_neg_visitor::visit_leave(ir_expression *ir) +{ + if (ir->operation != ir_binop_sub) + return visit_continue; + + void *mem_ctx = talloc_parent(ir); + + ir->operation = ir_binop_add; + ir->operands[1] = new(mem_ctx) ir_expression(ir_unop_neg, + ir->operands[1]->type, + ir->operands[1], + NULL); + + this->progress = true; + + return visit_continue; +} diff --git a/src/glsl/linker.cpp b/src/glsl/linker.cpp index 52c93227888..c462d31ef3d 100644 --- a/src/glsl/linker.cpp +++ b/src/glsl/linker.cpp @@ -1284,6 +1284,7 @@ link_shaders(struct gl_shader_program *prog) do_mod_to_fract(ir); do_div_to_mul_rcp(ir); do_explog_to_explog2(ir); + do_sub_to_add_neg(ir); do { progress = false; diff --git a/src/mesa/program/ir_to_mesa.cpp b/src/mesa/program/ir_to_mesa.cpp index 5a272ab88a1..a9a6f977c01 100644 --- a/src/mesa/program/ir_to_mesa.cpp +++ b/src/mesa/program/ir_to_mesa.cpp @@ -2570,6 +2570,7 @@ _mesa_glsl_compile_shader(GLcontext *ctx, struct gl_shader *shader) do_mat_op_to_vec(shader->ir); do_mod_to_fract(shader->ir); do_div_to_mul_rcp(shader->ir); + do_sub_to_add_neg(shader->ir); /* Optimization passes */ bool progress; -- 2.30.2