1 //===- InlineSimple.cpp - Code to perform simple function inlining --------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements bottom-up inlining of functions into callees.
12 //===----------------------------------------------------------------------===//
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"
32 class SimpleInliner : public Inliner {
33 // Functions that are never inlined
34 SmallPtrSet<const Function*, 16> NeverInline;
35 InlineCostAnalyzer CA;
37 SimpleInliner() : Inliner(ID) {
38 initializeSimpleInlinerPass(*PassRegistry::getPassRegistry());
40 SimpleInliner(int Threshold) : Inliner(ID, Threshold,
41 /*InsertLifetime*/true) {
42 initializeSimpleInlinerPass(*PassRegistry::getPassRegistry());
44 static char ID; // Pass identification, replacement for typeid
45 InlineCost getInlineCost(CallSite CS) {
46 return CA.getInlineCost(CS, NeverInline);
48 float getInlineFudgeFactor(CallSite CS) {
49 return CA.getInlineFudgeFactor(CS);
51 void resetCachedCostInfo(Function *Caller) {
52 CA.resetCachedCostInfo(Caller);
54 void growCachedCostInfo(Function* Caller, Function* Callee) {
55 CA.growCachedCostInfo(Caller, Callee);
57 virtual bool doInitialization(CallGraph &CG);
58 void releaseMemory() {
64 char SimpleInliner::ID = 0;
65 INITIALIZE_PASS_BEGIN(SimpleInliner, "inline",
66 "Function Integration/Inlining", false, false)
67 INITIALIZE_AG_DEPENDENCY(CallGraph)
68 INITIALIZE_PASS_END(SimpleInliner, "inline",
69 "Function Integration/Inlining", false, false)
71 Pass *llvm::createFunctionInliningPass() { return new SimpleInliner(); }
73 Pass *llvm::createFunctionInliningPass(int Threshold) {
74 return new SimpleInliner(Threshold);
77 // doInitialization - Initializes the vector of functions that have been
78 // annotated with the noinline attribute.
79 bool SimpleInliner::doInitialization(CallGraph &CG) {
80 CA.setTargetData(getAnalysisIfAvailable<TargetData>());
82 Module &M = CG.getModule();
84 for (Module::iterator I = M.begin(), E = M.end();
86 if (!I->isDeclaration() && I->hasFnAttr(Attribute::NoInline))
87 NeverInline.insert(I);
90 GlobalVariable *GV = M.getNamedGlobal("llvm.noinline");
95 // Don't crash on invalid code
96 if (!GV->hasDefinitiveInitializer())
99 const ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer());
104 // Iterate over each element and add to the NeverInline set
105 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
108 const Constant *Elt = InitList->getOperand(i);
110 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(Elt))
111 if (CE->getOpcode() == Instruction::BitCast)
112 Elt = CE->getOperand(0);
114 // Insert into set of functions to never inline
115 if (const Function *F = dyn_cast<Function>(Elt))
116 NeverInline.insert(F);