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 ir_function_can_inline.cpp 26 * 27 * Determines if we can inline a function call using ir_function_inlining.cpp. 28 * 29 * The primary restriction is that we can't return from the function other 30 * than as the last instruction. In lower_jumps.cpp, we can lower return 31 * statements not at the end of the function to other control flow in order to 32 * deal with this restriction. 33 */ 34 35 #include "ir.h" 36 37 class ir_function_can_inline_visitor : public ir_hierarchical_visitor { 38 public: 39 ir_function_can_inline_visitor() 40 { 41 this->num_returns = 0; 42 } 43 44 virtual ir_visitor_status visit_enter(ir_return *); 45 46 int num_returns; 47 }; 48 49 ir_visitor_status 50 ir_function_can_inline_visitor::visit_enter(ir_return *ir) 51 { 52 (void) ir; 53 this->num_returns++; 54 return visit_continue; 55 } 56 57 bool 58 can_inline(ir_call *call) 59 { 60 ir_function_can_inline_visitor v; 61 const ir_function_signature *callee = call->callee; 62 if (!callee->is_defined) 63 return false; 64 65 v.run((exec_list *) &callee->body); 66 67 /* If the function is empty (no last instruction) or does not end with a 68 * return statement, we need to count the implicit return. 69 */ 70 ir_instruction *last = (ir_instruction *)callee->body.get_tail(); 71 if (last == NULL || !last->as_return()) 72 v.num_returns++; 73 74 return v.num_returns == 1; 75 } 76