InlineAlways.cpp revision 193323
1//===- InlineAlways.cpp - Code to inline always_inline functions ----------===// 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 a custom inliner that handles only functions that 11// are marked as "always inline". 12// 13//===----------------------------------------------------------------------===// 14 15#define DEBUG_TYPE "inline" 16#include "llvm/CallingConv.h" 17#include "llvm/Instructions.h" 18#include "llvm/IntrinsicInst.h" 19#include "llvm/Module.h" 20#include "llvm/Type.h" 21#include "llvm/Analysis/CallGraph.h" 22#include "llvm/Support/CallSite.h" 23#include "llvm/Support/Compiler.h" 24#include "llvm/Transforms/IPO.h" 25#include "llvm/Transforms/IPO/InlinerPass.h" 26#include "llvm/Transforms/Utils/InlineCost.h" 27#include "llvm/ADT/SmallPtrSet.h" 28 29using namespace llvm; 30 31namespace { 32 33 // AlwaysInliner only inlines functions that are mark as "always inline". 34 class VISIBILITY_HIDDEN AlwaysInliner : public Inliner { 35 // Functions that are never inlined 36 SmallPtrSet<const Function*, 16> NeverInline; 37 InlineCostAnalyzer CA; 38 public: 39 // Use extremely low threshold. 40 AlwaysInliner() : Inliner(&ID, -2000000000) {} 41 static char ID; // Pass identification, replacement for typeid 42 InlineCost getInlineCost(CallSite CS) { 43 return CA.getInlineCost(CS, NeverInline); 44 } 45 float getInlineFudgeFactor(CallSite CS) { 46 return CA.getInlineFudgeFactor(CS); 47 } 48 void resetCachedCostInfo(Function *Caller) { 49 return CA.resetCachedCostInfo(Caller); 50 } 51 virtual bool doFinalization(CallGraph &CG) { 52 return removeDeadFunctions(CG, &NeverInline); 53 } 54 virtual bool doInitialization(CallGraph &CG); 55 }; 56} 57 58char AlwaysInliner::ID = 0; 59static RegisterPass<AlwaysInliner> 60X("always-inline", "Inliner for always_inline functions"); 61 62Pass *llvm::createAlwaysInlinerPass() { return new AlwaysInliner(); } 63 64// doInitialization - Initializes the vector of functions that have not 65// been annotated with the "always inline" attribute. 66bool AlwaysInliner::doInitialization(CallGraph &CG) { 67 Module &M = CG.getModule(); 68 69 for (Module::iterator I = M.begin(), E = M.end(); 70 I != E; ++I) 71 if (!I->isDeclaration() && !I->hasFnAttr(Attribute::AlwaysInline)) 72 NeverInline.insert(I); 73 74 return false; 75} 76