1 //===- InlineSimple.cpp - Code to perform simple function inlining --------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file implements bottom-up inlining of functions into callees. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "llvm/Transforms/IPO.h" 15 #include "llvm/Analysis/CallGraph.h" 16 #include "llvm/Analysis/InlineCost.h" 17 #include "llvm/IR/CallSite.h" 18 #include "llvm/IR/CallingConv.h" 19 #include "llvm/IR/DataLayout.h" 20 #include "llvm/IR/Instructions.h" 21 #include "llvm/IR/IntrinsicInst.h" 22 #include "llvm/IR/Module.h" 23 #include "llvm/IR/Type.h" 24 #include "llvm/Transforms/IPO/InlinerPass.h" 25 26 using namespace llvm; 27 28 #define DEBUG_TYPE "inline" 29 30 namespace { 31 32 /// \brief Actual inliner pass implementation. 33 /// 34 /// The common implementation of the inlining logic is shared between this 35 /// inliner pass and the always inliner pass. The two passes use different cost 36 /// analyses to determine when to inline. 37 class SimpleInliner : public Inliner { 38 InlineCostAnalysis *ICA; 39 40 public: 41 SimpleInliner() : Inliner(ID), ICA(nullptr) { 42 initializeSimpleInlinerPass(*PassRegistry::getPassRegistry()); 43 } 44 45 SimpleInliner(int Threshold) 46 : Inliner(ID, Threshold, /*InsertLifetime*/ true), ICA(nullptr) { 47 initializeSimpleInlinerPass(*PassRegistry::getPassRegistry()); 48 } 49 50 static char ID; // Pass identification, replacement for typeid 51 52 InlineCost getInlineCost(CallSite CS) override { 53 return ICA->getInlineCost(CS, getInlineThreshold(CS)); 54 } 55 56 bool runOnSCC(CallGraphSCC &SCC) override; 57 void getAnalysisUsage(AnalysisUsage &AU) const override; 58 }; 59 60 static int computeThresholdFromOptLevels(unsigned OptLevel, 61 unsigned SizeOptLevel) { 62 if (OptLevel > 2) 63 return 275; 64 if (SizeOptLevel == 1) // -Os 65 return 75; 66 if (SizeOptLevel == 2) // -Oz 67 return 25; 68 return 225; 69 } 70 71 } // end anonymous namespace 72 73 char SimpleInliner::ID = 0; 74 INITIALIZE_PASS_BEGIN(SimpleInliner, "inline", 75 "Function Integration/Inlining", false, false) 76 INITIALIZE_PASS_DEPENDENCY(CallGraphWrapperPass) 77 INITIALIZE_PASS_DEPENDENCY(InlineCostAnalysis) 78 INITIALIZE_PASS_END(SimpleInliner, "inline", 79 "Function Integration/Inlining", false, false) 80 81 Pass *llvm::createFunctionInliningPass() { return new SimpleInliner(); } 82 83 Pass *llvm::createFunctionInliningPass(int Threshold) { 84 return new SimpleInliner(Threshold); 85 } 86 87 Pass *llvm::createFunctionInliningPass(unsigned OptLevel, 88 unsigned SizeOptLevel) { 89 return new SimpleInliner( 90 computeThresholdFromOptLevels(OptLevel, SizeOptLevel)); 91 } 92 93 bool SimpleInliner::runOnSCC(CallGraphSCC &SCC) { 94 ICA = &getAnalysis<InlineCostAnalysis>(); 95 return Inliner::runOnSCC(SCC); 96 } 97 98 void SimpleInliner::getAnalysisUsage(AnalysisUsage &AU) const { 99 AU.addRequired<InlineCostAnalysis>(); 100 Inliner::getAnalysisUsage(AU); 101 } 102
