1 /* 2 * Copyright 2010 Intel Corporation 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 21 * DEALINGS IN THE SOFTWARE. 22 */ 23 24 /** 25 * \file lower_noise.cpp 26 * IR lower pass to remove noise opcodes. 27 * 28 * \author Ian Romanick <ian.d.romanick (at) intel.com> 29 */ 30 31 #include "ir.h" 32 #include "ir_rvalue_visitor.h" 33 34 class lower_noise_visitor : public ir_rvalue_visitor { 35 public: 36 lower_noise_visitor() : progress(false) 37 { 38 /* empty */ 39 } 40 41 void handle_rvalue(ir_rvalue **rvalue) 42 { 43 if (!*rvalue) 44 return; 45 46 ir_expression *expr = (*rvalue)->as_expression(); 47 if (!expr) 48 return; 49 50 /* In the future, ir_unop_noise may be replaced by a call to a function 51 * that implements noise. No hardware has a noise instruction. 52 */ 53 if (expr->operation == ir_unop_noise) { 54 *rvalue = ir_constant::zero(ralloc_parent(expr), expr->type); 55 this->progress = true; 56 } 57 } 58 59 bool progress; 60 }; 61 62 63 bool 64 lower_noise(exec_list *instructions) 65 { 66 lower_noise_visitor v; 67 68 visit_list_elements(&v, instructions); 69 70 return v.progress; 71 } 72
