From 5ba94206083fcd678febd6cac0231f35c0f1b77a Mon Sep 17 00:00:00 2001 From: Eric Anholt Date: Wed, 14 Apr 2010 17:03:03 -0700 Subject: [PATCH] Add an ir_if simplification pass. This is relatively simple at the moment, recognizing only constant values, and not (for example) values that are restricted to a range that make the branching constant. However, it does remove 59 lines from the printout of CorrectParse2.vert. --- Makefile.am | 3 +- glsl_parser_extras.cpp | 2 + ir.h | 6 + ir_if_simplification.cpp | 235 +++++++++++++++++++++++++++++++++++++++ ir_if_simplification.h | 31 ++++++ 5 files changed, 276 insertions(+), 1 deletion(-) create mode 100644 ir_if_simplification.cpp create mode 100644 ir_if_simplification.h diff --git a/Makefile.am b/Makefile.am index 6fac0a8c4c0..68a1d98d33e 100644 --- a/Makefile.am +++ b/Makefile.am @@ -30,7 +30,8 @@ glsl_SOURCES = symbol_table.c hash_table.c glsl_types.cpp \ ir_print_visitor.cpp ir_variable.cpp ir_function.cpp \ ir_constant_expression.cpp \ ir_constant_folding.cpp \ - ir_function_inlining.cpp + ir_function_inlining.cpp \ + ir_if_simplification.cpp BUILT_SOURCES = glsl_parser.h builtin_types.h glsl_parser.cpp glsl_lexer.cpp CLEANFILES = $(BUILT_SOURCES) diff --git a/glsl_parser_extras.cpp b/glsl_parser_extras.cpp index 38dee95c359..455bf0c7a4a 100644 --- a/glsl_parser_extras.cpp +++ b/glsl_parser_extras.cpp @@ -36,6 +36,7 @@ #include "glsl_parser.h" #include "ir_constant_folding.h" #include "ir_function_inlining.h" +#include "ir_if_simplification.h" #include "ir_print_visitor.h" const char * @@ -759,6 +760,7 @@ main(int argc, char **argv) progress = false; progress = do_function_inlining(&instructions) || progress; + progress = do_if_simplification(&instructions) || progress; /* Constant folding */ ir_constant_folding_visitor constant_folding; diff --git a/ir.h b/ir.h index 2d3a8cdb0b0..471e19b43d5 100644 --- a/ir.h +++ b/ir.h @@ -58,6 +58,7 @@ public: virtual class ir_assignment * as_assignment() { return NULL; } virtual class ir_call * as_call() { return NULL; } virtual class ir_return * as_return() { return NULL; } + virtual class ir_if * as_if() { return NULL; } /*@}*/ protected: @@ -299,6 +300,11 @@ public: /* empty */ } + virtual ir_if *as_if() + { + return this; + } + virtual void accept(ir_visitor *v) { v->visit(this); diff --git a/ir_if_simplification.cpp b/ir_if_simplification.cpp new file mode 100644 index 00000000000..5637db510ce --- /dev/null +++ b/ir_if_simplification.cpp @@ -0,0 +1,235 @@ +/* + * 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_function_inlining.cpp + * + * Moves constant branches of if statements out to the surrounding + * instruction stream. + */ + +#define NULL 0 +#include "ir.h" +#include "ir_visitor.h" +#include "ir_function_inlining.h" +#include "glsl_types.h" + +class ir_if_simplification_visitor : public ir_visitor { +public: + ir_if_simplification_visitor() + { + /* empty */ + } + + virtual ~ir_if_simplification_visitor() + { + /* empty */ + } + + /** + * \name Visit methods + * + * As typical for the visitor pattern, there must be one \c visit method for + * each concrete subclass of \c ir_instruction. Virtual base classes within + * the hierarchy should not have \c visit methods. + */ + /*@{*/ + virtual void visit(ir_variable *); + virtual void visit(ir_label *); + virtual void visit(ir_loop *); + virtual void visit(ir_loop_jump *); + virtual void visit(ir_function_signature *); + virtual void visit(ir_function *); + virtual void visit(ir_expression *); + virtual void visit(ir_swizzle *); + virtual void visit(ir_dereference *); + virtual void visit(ir_assignment *); + virtual void visit(ir_constant *); + virtual void visit(ir_call *); + virtual void visit(ir_return *); + virtual void visit(ir_if *); + /*@}*/ +}; + +bool +do_if_simplification(exec_list *instructions) +{ + bool progress = false; + + foreach_iter(exec_list_iterator, iter, *instructions) { + ir_instruction *ir = (ir_instruction *)iter.get(); + ir_if *conditional = ir->as_if(); + + if (conditional) { + ir_constant *condition_constant; + + condition_constant = + conditional->condition->constant_expression_value(); + if (condition_constant) { + /* Move the contents of the one branch of the conditional + * that matters out. + */ + if (condition_constant->value.b[0]) { + foreach_iter(exec_list_iterator, then_iter, + conditional->then_instructions) { + ir_instruction *then_ir = (ir_instruction *)then_iter.get(); + ir->insert_before(then_ir); + } + } else { + foreach_iter(exec_list_iterator, else_iter, + conditional->else_instructions) { + ir_instruction *else_ir = (ir_instruction *)else_iter.get(); + ir->insert_before(else_ir); + } + } + ir->remove(); + progress = true; + /* It would be nice to move the iterator back up to the point + * that we just spliced in contents. + */ + } else { + ir_if_simplification_visitor v; + ir->accept(&v); + } + } else { + ir_if_simplification_visitor v; + ir->accept(&v); + } + } + + return progress; +} + +class variable_remap : public exec_node { +public: + variable_remap(const ir_variable *old_var, ir_variable *new_var) + : old_var(old_var), new_var(new_var) + { + /* empty */ + } + const ir_variable *old_var; + ir_variable *new_var; +}; + +void +ir_if_simplification_visitor::visit(ir_variable *ir) +{ + (void) ir; +} + + +void +ir_if_simplification_visitor::visit(ir_label *ir) +{ + ir->signature->accept(this); +} + +void +ir_if_simplification_visitor::visit(ir_loop *ir) +{ + do_if_simplification(&ir->body_instructions); +} + +void +ir_if_simplification_visitor::visit(ir_loop_jump *ir) +{ + (void) ir; +} + + +void +ir_if_simplification_visitor::visit(ir_function_signature *ir) +{ + do_if_simplification(&ir->body); +} + + +void +ir_if_simplification_visitor::visit(ir_function *ir) +{ + (void) ir; +} + +void +ir_if_simplification_visitor::visit(ir_expression *ir) +{ + unsigned int operand; + + for (operand = 0; operand < ir->get_num_operands(); operand++) { + ir->operands[operand]->accept(this); + } +} + + +void +ir_if_simplification_visitor::visit(ir_swizzle *ir) +{ + ir->val->accept(this); +} + + +void +ir_if_simplification_visitor::visit(ir_dereference *ir) +{ + if (ir->mode == ir_dereference::ir_reference_array) { + ir->selector.array_index->accept(this); + } + ir->var->accept(this); +} + +void +ir_if_simplification_visitor::visit(ir_assignment *ir) +{ + ir->rhs->accept(this); +} + + +void +ir_if_simplification_visitor::visit(ir_constant *ir) +{ + (void) ir; +} + + +void +ir_if_simplification_visitor::visit(ir_call *ir) +{ + (void) ir; +} + + +void +ir_if_simplification_visitor::visit(ir_return *ir) +{ + (void) ir; +} + + +void +ir_if_simplification_visitor::visit(ir_if *ir) +{ + ir->condition->accept(this); + + do_if_simplification(&ir->then_instructions); + do_if_simplification(&ir->else_instructions); +} diff --git a/ir_if_simplification.h b/ir_if_simplification.h new file mode 100644 index 00000000000..84b09ef0fd3 --- /dev/null +++ b/ir_if_simplification.h @@ -0,0 +1,31 @@ +/* + * 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_if_simplification.h + * + * Moves constant branches of if statements out to the surrounding + * instruction stream. + */ + +bool do_if_simplification(exec_list *instructions); -- 2.30.2