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 #define DEBUG_TYPE "inline" 15 #include "llvm/CallingConv.h" 16 #include "llvm/Instructions.h" 17 #include "llvm/IntrinsicInst.h" 18 #include "llvm/Module.h" 19 #include "llvm/Type.h" 20 #include "llvm/Analysis/CallGraph.h" 21 #include "llvm/Analysis/InlineCost.h" 22 #include "llvm/Support/CallSite.h" 23 #include "llvm/Transforms/IPO.h" 24 #include "llvm/Transforms/IPO/InlinerPass.h" 25 #include "llvm/Target/TargetData.h" 26 #include "llvm/ADT/SmallPtrSet.h" 27 28 using namespace llvm; 29 30 namespace { 31 32 class SimpleInliner : public Inliner { 33 // Functions that are never inlined 34 SmallPtrSet<const Function*, 16> NeverInline; 35 InlineCostAnalyzer CA; 36 public: 37 SimpleInliner() : Inliner(ID) { 38 initializeSimpleInlinerPass(*PassRegistry::getPassRegistry()); 39 } 40 SimpleInliner(int Threshold) : Inliner(ID, Threshold) { 41 initializeSimpleInlinerPass(*PassRegistry::getPassRegistry()); 42 } 43 static char ID; // Pass identification, replacement for typeid 44 InlineCost getInlineCost(CallSite CS) { 45 return CA.getInlineCost(CS, NeverInline); 46 } 47 float getInlineFudgeFactor(CallSite CS) { 48 return CA.getInlineFudgeFactor(CS); 49 } 50 void resetCachedCostInfo(Function *Caller) { 51 CA.resetCachedCostInfo(Caller); 52 } 53 void growCachedCostInfo(Function* Caller, Function* Callee) { 54 CA.growCachedCostInfo(Caller, Callee); 55 } 56 virtual bool doInitialization(CallGraph &CG); 57 void releaseMemory() { 58 CA.clear(); 59 } 60 }; 61 } 62 63 char SimpleInliner::ID = 0; 64 INITIALIZE_PASS_BEGIN(SimpleInliner, "inline", 65 "Function Integration/Inlining", false, false) 66 INITIALIZE_AG_DEPENDENCY(CallGraph) 67 INITIALIZE_PASS_END(SimpleInliner, "inline", 68 "Function Integration/Inlining", false, false) 69 70 Pass *llvm::createFunctionInliningPass() { return new SimpleInliner(); } 71 72 Pass *llvm::createFunctionInliningPass(int Threshold) { 73 return new SimpleInliner(Threshold); 74 } 75 76 // doInitialization - Initializes the vector of functions that have been 77 // annotated with the noinline attribute. 78 bool SimpleInliner::doInitialization(CallGraph &CG) { 79 CA.setTargetData(getAnalysisIfAvailable<TargetData>()); 80 81 Module &M = CG.getModule(); 82 83 for (Module::iterator I = M.begin(), E = M.end(); 84 I != E; ++I) 85 if (!I->isDeclaration() && I->hasFnAttr(Attribute::NoInline)) 86 NeverInline.insert(I); 87 88 // Get llvm.noinline 89 GlobalVariable *GV = M.getNamedGlobal("llvm.noinline"); 90 91 if (GV == 0) 92 return false; 93 94 // Don't crash on invalid code 95 if (!GV->hasDefinitiveInitializer()) 96 return false; 97 98 const ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer()); 99 100 if (InitList == 0) 101 return false; 102 103 // Iterate over each element and add to the NeverInline set 104 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) { 105 106 // Get Source 107 const Constant *Elt = InitList->getOperand(i); 108 109 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(Elt)) 110 if (CE->getOpcode() == Instruction::BitCast) 111 Elt = CE->getOperand(0); 112 113 // Insert into set of functions to never inline 114 if (const Function *F = dyn_cast<Function>(Elt)) 115 NeverInline.insert(F); 116 } 117 118 return false; 119 } 120 121
