CodeGenPrepare.cpp [plain text]
#define DEBUG_TYPE "codegenprepare"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/InlineAsm.h"
#include "llvm/Instructions.h"
#include "llvm/IntrinsicInst.h"
#include "llvm/Pass.h"
#include "llvm/Analysis/ProfileInfo.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Transforms/Utils/AddrModeMatcher.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/BuildLibCalls.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/Assembly/Writer.h"
#include "llvm/Support/CallSite.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "llvm/Support/PatternMatch.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/IRBuilder.h"
using namespace llvm;
using namespace llvm::PatternMatch;
namespace {
class CodeGenPrepare : public FunctionPass {
const TargetLowering *TLI;
ProfileInfo *PFI;
SmallSet<std::pair<const BasicBlock*, const BasicBlock*>, 8> BackEdges;
public:
static char ID; explicit CodeGenPrepare(const TargetLowering *tli = 0)
: FunctionPass(&ID), TLI(tli) {}
bool runOnFunction(Function &F);
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.addPreserved<ProfileInfo>();
}
virtual void releaseMemory() {
BackEdges.clear();
}
private:
bool EliminateMostlyEmptyBlocks(Function &F);
bool CanMergeBlocks(const BasicBlock *BB, const BasicBlock *DestBB) const;
void EliminateMostlyEmptyBlock(BasicBlock *BB);
bool OptimizeBlock(BasicBlock &BB);
bool OptimizeMemoryInst(Instruction *I, Value *Addr, const Type *AccessTy,
DenseMap<Value*,Value*> &SunkAddrs);
bool OptimizeInlineAsmInst(Instruction *I, CallSite CS,
DenseMap<Value*,Value*> &SunkAddrs);
bool OptimizeCallInst(CallInst *CI);
bool MoveExtToFormExtLoad(Instruction *I);
bool OptimizeExtUses(Instruction *I);
void findLoopBackEdges(const Function &F);
};
}
char CodeGenPrepare::ID = 0;
static RegisterPass<CodeGenPrepare> X("codegenprepare",
"Optimize for code generation");
FunctionPass *llvm::createCodeGenPreparePass(const TargetLowering *TLI) {
return new CodeGenPrepare(TLI);
}
void CodeGenPrepare::findLoopBackEdges(const Function &F) {
SmallVector<std::pair<const BasicBlock*,const BasicBlock*>, 32> Edges;
FindFunctionBackedges(F, Edges);
BackEdges.insert(Edges.begin(), Edges.end());
}
bool CodeGenPrepare::runOnFunction(Function &F) {
bool EverMadeChange = false;
PFI = getAnalysisIfAvailable<ProfileInfo>();
EverMadeChange |= EliminateMostlyEmptyBlocks(F);
findLoopBackEdges(F);
bool MadeChange = true;
while (MadeChange) {
MadeChange = false;
for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
MadeChange |= OptimizeBlock(*BB);
EverMadeChange |= MadeChange;
}
return EverMadeChange;
}
bool CodeGenPrepare::EliminateMostlyEmptyBlocks(Function &F) {
bool MadeChange = false;
for (Function::iterator I = ++F.begin(), E = F.end(); I != E; ) {
BasicBlock *BB = I++;
BranchInst *BI = dyn_cast<BranchInst>(BB->getTerminator());
if (!BI || !BI->isUnconditional())
continue;
BasicBlock::iterator BBI = BI;
if (BBI != BB->begin()) {
--BBI;
while (isa<DbgInfoIntrinsic>(BBI)) {
if (BBI == BB->begin())
break;
--BBI;
}
if (!isa<DbgInfoIntrinsic>(BBI) && !isa<PHINode>(BBI))
continue;
}
BasicBlock *DestBB = BI->getSuccessor(0);
if (DestBB == BB)
continue;
if (!CanMergeBlocks(BB, DestBB))
continue;
EliminateMostlyEmptyBlock(BB);
MadeChange = true;
}
return MadeChange;
}
bool CodeGenPrepare::CanMergeBlocks(const BasicBlock *BB,
const BasicBlock *DestBB) const {
BasicBlock::const_iterator BBI = BB->begin();
while (const PHINode *PN = dyn_cast<PHINode>(BBI++)) {
for (Value::use_const_iterator UI = PN->use_begin(), E = PN->use_end();
UI != E; ++UI) {
const Instruction *User = cast<Instruction>(*UI);
if (User->getParent() != DestBB || !isa<PHINode>(User))
return false;
if (User->getParent() == DestBB) {
if (const PHINode *UPN = dyn_cast<PHINode>(User))
for (unsigned I = 0, E = UPN->getNumIncomingValues(); I != E; ++I) {
Instruction *Insn = dyn_cast<Instruction>(UPN->getIncomingValue(I));
if (Insn && Insn->getParent() == BB &&
Insn->getParent() != UPN->getIncomingBlock(I))
return false;
}
}
}
}
const PHINode *DestBBPN = dyn_cast<PHINode>(DestBB->begin());
if (!DestBBPN) return true;
SmallPtrSet<const BasicBlock*, 16> BBPreds;
if (const PHINode *BBPN = dyn_cast<PHINode>(BB->begin())) {
for (unsigned i = 0, e = BBPN->getNumIncomingValues(); i != e; ++i)
BBPreds.insert(BBPN->getIncomingBlock(i));
} else {
BBPreds.insert(pred_begin(BB), pred_end(BB));
}
for (unsigned i = 0, e = DestBBPN->getNumIncomingValues(); i != e; ++i) {
BasicBlock *Pred = DestBBPN->getIncomingBlock(i);
if (BBPreds.count(Pred)) { BBI = DestBB->begin();
while (const PHINode *PN = dyn_cast<PHINode>(BBI++)) {
const Value *V1 = PN->getIncomingValueForBlock(Pred);
const Value *V2 = PN->getIncomingValueForBlock(BB);
if (const PHINode *V2PN = dyn_cast<PHINode>(V2))
if (V2PN->getParent() == BB)
V2 = V2PN->getIncomingValueForBlock(Pred);
if (V1 != V2) return false;
}
}
}
return true;
}
void CodeGenPrepare::EliminateMostlyEmptyBlock(BasicBlock *BB) {
BranchInst *BI = cast<BranchInst>(BB->getTerminator());
BasicBlock *DestBB = BI->getSuccessor(0);
DEBUG(dbgs() << "MERGING MOSTLY EMPTY BLOCKS - BEFORE:\n" << *BB << *DestBB);
if (BasicBlock *SinglePred = DestBB->getSinglePredecessor()) {
if (SinglePred != DestBB) {
bool isEntry = SinglePred == &SinglePred->getParent()->getEntryBlock();
MergeBasicBlockIntoOnlyPred(DestBB, this);
if (isEntry && BB != &BB->getParent()->getEntryBlock())
BB->moveBefore(&BB->getParent()->getEntryBlock());
DEBUG(dbgs() << "AFTER:\n" << *DestBB << "\n\n\n");
return;
}
}
PHINode *PN;
for (BasicBlock::iterator BBI = DestBB->begin();
(PN = dyn_cast<PHINode>(BBI)); ++BBI) {
Value *InVal = PN->removeIncomingValue(BB, false);
PHINode *InValPhi = dyn_cast<PHINode>(InVal);
if (InValPhi && InValPhi->getParent() == BB) {
for (unsigned i = 0, e = InValPhi->getNumIncomingValues(); i != e; ++i)
PN->addIncoming(InValPhi->getIncomingValue(i),
InValPhi->getIncomingBlock(i));
} else {
if (PHINode *BBPN = dyn_cast<PHINode>(BB->begin())) {
for (unsigned i = 0, e = BBPN->getNumIncomingValues(); i != e; ++i)
PN->addIncoming(InVal, BBPN->getIncomingBlock(i));
} else {
for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI)
PN->addIncoming(InVal, *PI);
}
}
}
BB->replaceAllUsesWith(DestBB);
if (PFI) {
PFI->replaceAllUses(BB, DestBB);
PFI->removeEdge(ProfileInfo::getEdge(BB, DestBB));
}
BB->eraseFromParent();
DEBUG(dbgs() << "AFTER:\n" << *DestBB << "\n\n\n");
}
static BasicBlock *FindReusablePredBB(PHINode *DestPHI, BasicBlock *TIBB) {
BasicBlock *Dest = DestPHI->getParent();
SmallVector<Value*, 32> TIPHIValues;
unsigned TIBBEntryNo = 0;
for (unsigned pi = 0, e = DestPHI->getNumIncomingValues(); pi != e; ++pi) {
BasicBlock *Pred = DestPHI->getIncomingBlock(pi);
BranchInst *PredBr = dyn_cast<BranchInst>(Pred->getTerminator());
if (!PredBr || !PredBr->isUnconditional())
continue;
BasicBlock::iterator I = Pred->begin();
while (isa<DbgInfoIntrinsic>(I))
I++;
if (&*I != PredBr)
continue;
if (Pred == &Dest->getParent()->getEntryBlock())
continue;
PHINode *PN;
unsigned PHINo = 0;
unsigned PredEntryNo = pi;
bool FoundMatch = true;
for (BasicBlock::iterator I = Dest->begin();
(PN = dyn_cast<PHINode>(I)); ++I, ++PHINo) {
if (PHINo == TIPHIValues.size()) {
if (PN->getIncomingBlock(TIBBEntryNo) != TIBB)
TIBBEntryNo = PN->getBasicBlockIndex(TIBB);
TIPHIValues.push_back(PN->getIncomingValue(TIBBEntryNo));
}
if (PN->getIncomingBlock(PredEntryNo) != Pred)
PredEntryNo = PN->getBasicBlockIndex(Pred);
if (TIPHIValues[PHINo] != PN->getIncomingValue(PredEntryNo)) {
FoundMatch = false;
break;
}
}
if (FoundMatch)
return Pred;
}
return 0;
}
static void SplitEdgeNicely(TerminatorInst *TI, unsigned SuccNum,
SmallSet<std::pair<const BasicBlock*,
const BasicBlock*>, 8> &BackEdges,
Pass *P) {
BasicBlock *TIBB = TI->getParent();
BasicBlock *Dest = TI->getSuccessor(SuccNum);
assert(isa<PHINode>(Dest->begin()) &&
"This should only be called if Dest has a PHI!");
PHINode *DestPHI = cast<PHINode>(Dest->begin());
if (InvokeInst *Invoke = dyn_cast<InvokeInst>(TI))
if (Invoke->getSuccessor(1) == Dest)
return;
if (BackEdges.count(std::make_pair(TIBB, Dest)))
return;
if (BasicBlock *ReuseBB = FindReusablePredBB(DestPHI, TIBB)) {
ProfileInfo *PFI = P->getAnalysisIfAvailable<ProfileInfo>();
if (PFI)
PFI->splitEdge(TIBB, Dest, ReuseBB);
Dest->removePredecessor(TIBB);
TI->setSuccessor(SuccNum, ReuseBB);
return;
}
SplitCriticalEdge(TI, SuccNum, P, true);
}
static bool OptimizeNoopCopyExpression(CastInst *CI, const TargetLowering &TLI){
EVT SrcVT = TLI.getValueType(CI->getOperand(0)->getType());
EVT DstVT = TLI.getValueType(CI->getType());
if (SrcVT.isInteger() != DstVT.isInteger())
return false;
if (SrcVT.bitsLT(DstVT)) return false;
if (TLI.getTypeAction(CI->getContext(), SrcVT) == TargetLowering::Promote)
SrcVT = TLI.getTypeToTransformTo(CI->getContext(), SrcVT);
if (TLI.getTypeAction(CI->getContext(), DstVT) == TargetLowering::Promote)
DstVT = TLI.getTypeToTransformTo(CI->getContext(), DstVT);
if (SrcVT != DstVT)
return false;
BasicBlock *DefBB = CI->getParent();
DenseMap<BasicBlock*, CastInst*> InsertedCasts;
bool MadeChange = false;
for (Value::use_iterator UI = CI->use_begin(), E = CI->use_end();
UI != E; ) {
Use &TheUse = UI.getUse();
Instruction *User = cast<Instruction>(*UI);
BasicBlock *UserBB = User->getParent();
if (PHINode *PN = dyn_cast<PHINode>(User)) {
UserBB = PN->getIncomingBlock(UI);
}
++UI;
if (UserBB == DefBB) continue;
CastInst *&InsertedCast = InsertedCasts[UserBB];
if (!InsertedCast) {
BasicBlock::iterator InsertPt = UserBB->getFirstNonPHI();
InsertedCast =
CastInst::Create(CI->getOpcode(), CI->getOperand(0), CI->getType(), "",
InsertPt);
MadeChange = true;
}
TheUse = InsertedCast;
}
if (CI->use_empty()) {
CI->eraseFromParent();
MadeChange = true;
}
return MadeChange;
}
static bool OptimizeCmpExpression(CmpInst *CI) {
BasicBlock *DefBB = CI->getParent();
DenseMap<BasicBlock*, CmpInst*> InsertedCmps;
bool MadeChange = false;
for (Value::use_iterator UI = CI->use_begin(), E = CI->use_end();
UI != E; ) {
Use &TheUse = UI.getUse();
Instruction *User = cast<Instruction>(*UI);
++UI;
if (isa<PHINode>(User))
continue;
BasicBlock *UserBB = User->getParent();
if (UserBB == DefBB) continue;
CmpInst *&InsertedCmp = InsertedCmps[UserBB];
if (!InsertedCmp) {
BasicBlock::iterator InsertPt = UserBB->getFirstNonPHI();
InsertedCmp =
CmpInst::Create(CI->getOpcode(),
CI->getPredicate(), CI->getOperand(0),
CI->getOperand(1), "", InsertPt);
MadeChange = true;
}
TheUse = InsertedCmp;
}
if (CI->use_empty())
CI->eraseFromParent();
return MadeChange;
}
namespace {
class CodeGenPrepareFortifiedLibCalls : public SimplifyFortifiedLibCalls {
protected:
void replaceCall(Value *With) {
CI->replaceAllUsesWith(With);
CI->eraseFromParent();
}
bool isFoldable(unsigned SizeCIOp, unsigned, bool) const {
if (ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getOperand(SizeCIOp)))
return SizeCI->isAllOnesValue();
return false;
}
};
}
bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
IntrinsicInst *II = dyn_cast<IntrinsicInst>(CI);
if (II && II->getIntrinsicID() == Intrinsic::objectsize) {
bool Min = (cast<ConstantInt>(II->getOperand(2))->getZExtValue() == 1);
const Type *ReturnTy = CI->getType();
Constant *RetVal = ConstantInt::get(ReturnTy, Min ? 0 : -1ULL);
CI->replaceAllUsesWith(RetVal);
CI->eraseFromParent();
return true;
}
if (CI->getCalledFunction() == 0) return false;
const TargetData *TD = TLI ? TLI->getTargetData() : 0;
if (!TD) return false;
CodeGenPrepareFortifiedLibCalls Simplifier;
return Simplifier.fold(CI, TD);
}
static bool IsNonLocalValue(Value *V, BasicBlock *BB) {
if (Instruction *I = dyn_cast<Instruction>(V))
return I->getParent() != BB;
return false;
}
bool CodeGenPrepare::OptimizeMemoryInst(Instruction *MemoryInst, Value *Addr,
const Type *AccessTy,
DenseMap<Value*,Value*> &SunkAddrs) {
SmallVector<Instruction*, 16> AddrModeInsts;
ExtAddrMode AddrMode = AddressingModeMatcher::Match(Addr, AccessTy,MemoryInst,
AddrModeInsts, *TLI);
bool AnyNonLocal = false;
for (unsigned i = 0, e = AddrModeInsts.size(); i != e; ++i) {
if (IsNonLocalValue(AddrModeInsts[i], MemoryInst->getParent())) {
AnyNonLocal = true;
break;
}
}
if (!AnyNonLocal) {
DEBUG(dbgs() << "CGP: Found local addrmode: " << AddrMode << "\n");
return false;
}
BasicBlock::iterator InsertPt = MemoryInst;
Value *&SunkAddr = SunkAddrs[Addr];
if (SunkAddr) {
DEBUG(dbgs() << "CGP: Reusing nonlocal addrmode: " << AddrMode << " for "
<< *MemoryInst);
if (SunkAddr->getType() != Addr->getType())
SunkAddr = new BitCastInst(SunkAddr, Addr->getType(), "tmp", InsertPt);
} else {
DEBUG(dbgs() << "CGP: SINKING nonlocal addrmode: " << AddrMode << " for "
<< *MemoryInst);
const Type *IntPtrTy =
TLI->getTargetData()->getIntPtrType(AccessTy->getContext());
Value *Result = 0;
if (AddrMode.BaseReg) {
Value *V = AddrMode.BaseReg;
if (V->getType()->isPointerTy())
V = new PtrToIntInst(V, IntPtrTy, "sunkaddr", InsertPt);
if (V->getType() != IntPtrTy)
V = CastInst::CreateIntegerCast(V, IntPtrTy, true,
"sunkaddr", InsertPt);
Result = V;
}
if (AddrMode.Scale) {
Value *V = AddrMode.ScaledReg;
if (V->getType() == IntPtrTy) {
} else if (V->getType()->isPointerTy()) {
V = new PtrToIntInst(V, IntPtrTy, "sunkaddr", InsertPt);
} else if (cast<IntegerType>(IntPtrTy)->getBitWidth() <
cast<IntegerType>(V->getType())->getBitWidth()) {
V = new TruncInst(V, IntPtrTy, "sunkaddr", InsertPt);
} else {
V = new SExtInst(V, IntPtrTy, "sunkaddr", InsertPt);
}
if (AddrMode.Scale != 1)
V = BinaryOperator::CreateMul(V, ConstantInt::get(IntPtrTy,
AddrMode.Scale),
"sunkaddr", InsertPt);
if (Result)
Result = BinaryOperator::CreateAdd(Result, V, "sunkaddr", InsertPt);
else
Result = V;
}
if (AddrMode.BaseGV) {
Value *V = new PtrToIntInst(AddrMode.BaseGV, IntPtrTy, "sunkaddr",
InsertPt);
if (Result)
Result = BinaryOperator::CreateAdd(Result, V, "sunkaddr", InsertPt);
else
Result = V;
}
if (AddrMode.BaseOffs) {
Value *V = ConstantInt::get(IntPtrTy, AddrMode.BaseOffs);
if (Result)
Result = BinaryOperator::CreateAdd(Result, V, "sunkaddr", InsertPt);
else
Result = V;
}
if (Result == 0)
SunkAddr = Constant::getNullValue(Addr->getType());
else
SunkAddr = new IntToPtrInst(Result, Addr->getType(), "sunkaddr",InsertPt);
}
MemoryInst->replaceUsesOfWith(Addr, SunkAddr);
if (Addr->use_empty()) {
RecursivelyDeleteTriviallyDeadInstructions(Addr);
SunkAddrs[Addr] = 0;
}
return true;
}
bool CodeGenPrepare::OptimizeInlineAsmInst(Instruction *I, CallSite CS,
DenseMap<Value*,Value*> &SunkAddrs) {
bool MadeChange = false;
InlineAsm *IA = cast<InlineAsm>(CS.getCalledValue());
std::vector<InlineAsm::ConstraintInfo>
ConstraintInfos = IA->ParseConstraints();
std::vector<TargetLowering::AsmOperandInfo> ConstraintOperands;
unsigned ArgNo = 0; for (unsigned i = 0, e = ConstraintInfos.size(); i != e; ++i) {
ConstraintOperands.
push_back(TargetLowering::AsmOperandInfo(ConstraintInfos[i]));
TargetLowering::AsmOperandInfo &OpInfo = ConstraintOperands.back();
switch (OpInfo.Type) {
case InlineAsm::isOutput:
if (OpInfo.isIndirect)
OpInfo.CallOperandVal = CS.getArgument(ArgNo++);
break;
case InlineAsm::isInput:
OpInfo.CallOperandVal = CS.getArgument(ArgNo++);
break;
case InlineAsm::isClobber:
break;
}
TLI->ComputeConstraintToUse(OpInfo, SDValue(),
OpInfo.ConstraintType == TargetLowering::C_Memory);
if (OpInfo.ConstraintType == TargetLowering::C_Memory &&
OpInfo.isIndirect) {
Value *OpVal = OpInfo.CallOperandVal;
MadeChange |= OptimizeMemoryInst(I, OpVal, OpVal->getType(), SunkAddrs);
}
}
return MadeChange;
}
bool CodeGenPrepare::MoveExtToFormExtLoad(Instruction *I) {
LoadInst *LI = dyn_cast<LoadInst>(I->getOperand(0));
if (!LI) return false;
if (LI->getParent() == I->getParent())
return false;
if (!LI->hasOneUse() &&
TLI && !TLI->isTruncateFree(I->getType(), LI->getType()))
return false;
unsigned LType;
if (isa<ZExtInst>(I))
LType = ISD::ZEXTLOAD;
else {
assert(isa<SExtInst>(I) && "Unexpected ext type!");
LType = ISD::SEXTLOAD;
}
if (TLI && !TLI->isLoadExtLegal(LType, TLI->getValueType(LI->getType())))
return false;
I->removeFromParent();
I->insertAfter(LI);
return true;
}
bool CodeGenPrepare::OptimizeExtUses(Instruction *I) {
BasicBlock *DefBB = I->getParent();
Value *Src = I->getOperand(0);
if (Src->hasOneUse())
return false;
if (TLI && !TLI->isTruncateFree(I->getType(), Src->getType()))
return false;
if (!isa<Instruction>(Src) || DefBB != cast<Instruction>(Src)->getParent())
return false;
bool DefIsLiveOut = false;
for (Value::use_iterator UI = I->use_begin(), E = I->use_end();
UI != E; ++UI) {
Instruction *User = cast<Instruction>(*UI);
BasicBlock *UserBB = User->getParent();
if (UserBB == DefBB) continue;
DefIsLiveOut = true;
break;
}
if (!DefIsLiveOut)
return false;
for (Value::use_iterator UI = Src->use_begin(), E = Src->use_end();
UI != E; ++UI) {
Instruction *User = cast<Instruction>(*UI);
BasicBlock *UserBB = User->getParent();
if (UserBB == DefBB) continue;
if (isa<PHINode>(User) || isa<LoadInst>(User) || isa<StoreInst>(User))
return false;
}
DenseMap<BasicBlock*, Instruction*> InsertedTruncs;
bool MadeChange = false;
for (Value::use_iterator UI = Src->use_begin(), E = Src->use_end();
UI != E; ++UI) {
Use &TheUse = UI.getUse();
Instruction *User = cast<Instruction>(*UI);
BasicBlock *UserBB = User->getParent();
if (UserBB == DefBB) continue;
Instruction *&InsertedTrunc = InsertedTruncs[UserBB];
if (!InsertedTrunc) {
BasicBlock::iterator InsertPt = UserBB->getFirstNonPHI();
InsertedTrunc = new TruncInst(I, Src->getType(), "", InsertPt);
}
TheUse = InsertedTrunc;
MadeChange = true;
}
return MadeChange;
}
bool CodeGenPrepare::OptimizeBlock(BasicBlock &BB) {
bool MadeChange = false;
TerminatorInst *BBTI = BB.getTerminator();
if (BBTI->getNumSuccessors() > 1 && !isa<IndirectBrInst>(BBTI)) {
for (unsigned i = 0, e = BBTI->getNumSuccessors(); i != e; ++i) {
BasicBlock *SuccBB = BBTI->getSuccessor(i);
if (isa<PHINode>(SuccBB->begin()) && isCriticalEdge(BBTI, i, true))
SplitEdgeNicely(BBTI, i, BackEdges, this);
}
}
DenseMap<Value*, Value*> SunkAddrs;
for (BasicBlock::iterator BBI = BB.begin(), E = BB.end(); BBI != E; ) {
Instruction *I = BBI++;
if (CastInst *CI = dyn_cast<CastInst>(I)) {
if (isa<Constant>(CI->getOperand(0)))
continue;
bool Change = false;
if (TLI) {
Change = OptimizeNoopCopyExpression(CI, *TLI);
MadeChange |= Change;
}
if (!Change && (isa<ZExtInst>(I) || isa<SExtInst>(I))) {
MadeChange |= MoveExtToFormExtLoad(I);
MadeChange |= OptimizeExtUses(I);
}
} else if (CmpInst *CI = dyn_cast<CmpInst>(I)) {
MadeChange |= OptimizeCmpExpression(CI);
} else if (LoadInst *LI = dyn_cast<LoadInst>(I)) {
if (TLI)
MadeChange |= OptimizeMemoryInst(I, I->getOperand(0), LI->getType(),
SunkAddrs);
} else if (StoreInst *SI = dyn_cast<StoreInst>(I)) {
if (TLI)
MadeChange |= OptimizeMemoryInst(I, SI->getOperand(1),
SI->getOperand(0)->getType(),
SunkAddrs);
} else if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(I)) {
if (GEPI->hasAllZeroIndices()) {
Instruction *NC = new BitCastInst(GEPI->getOperand(0), GEPI->getType(),
GEPI->getName(), GEPI);
GEPI->replaceAllUsesWith(NC);
GEPI->eraseFromParent();
MadeChange = true;
BBI = NC;
}
} else if (CallInst *CI = dyn_cast<CallInst>(I)) {
if (TLI && isa<InlineAsm>(CI->getCalledValue())) {
if (TLI->ExpandInlineAsm(CI)) {
BBI = BB.begin();
SunkAddrs.clear();
} else
MadeChange |= OptimizeInlineAsmInst(I, &(*CI), SunkAddrs);
} else {
MadeChange |= OptimizeCallInst(CI);
}
}
}
return MadeChange;
}