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-rw-r--r--llvm/lib/Transforms/InstCombine/InstructionCombining.cpp118
1 files changed, 59 insertions, 59 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
index bc9a43fa7ec..f0964e8d39e 100644
--- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -513,7 +513,7 @@ Value *InstCombiner::SimplifyUsingDistributiveLaws(BinaryOperator &I) {
}
}
- return 0;
+ return nullptr;
}
// dyn_castNegVal - Given a 'sub' instruction, return the RHS of the instruction
@@ -531,7 +531,7 @@ Value *InstCombiner::dyn_castNegVal(Value *V) const {
if (C->getType()->getElementType()->isIntegerTy())
return ConstantExpr::getNeg(C);
- return 0;
+ return nullptr;
}
// dyn_castFNegVal - Given a 'fsub' instruction, return the RHS of the
@@ -550,7 +550,7 @@ Value *InstCombiner::dyn_castFNegVal(Value *V, bool IgnoreZeroSign) const {
if (C->getType()->getElementType()->isFloatingPointTy())
return ConstantExpr::getFNeg(C);
- return 0;
+ return nullptr;
}
static Value *FoldOperationIntoSelectOperand(Instruction &I, Value *SO,
@@ -596,13 +596,13 @@ static Value *FoldOperationIntoSelectOperand(Instruction &I, Value *SO,
// not have a second operand.
Instruction *InstCombiner::FoldOpIntoSelect(Instruction &Op, SelectInst *SI) {
// Don't modify shared select instructions
- if (!SI->hasOneUse()) return 0;
+ if (!SI->hasOneUse()) return nullptr;
Value *TV = SI->getOperand(1);
Value *FV = SI->getOperand(2);
if (isa<Constant>(TV) || isa<Constant>(FV)) {
// Bool selects with constant operands can be folded to logical ops.
- if (SI->getType()->isIntegerTy(1)) return 0;
+ if (SI->getType()->isIntegerTy(1)) return nullptr;
// If it's a bitcast involving vectors, make sure it has the same number of
// elements on both sides.
@@ -611,10 +611,10 @@ Instruction *InstCombiner::FoldOpIntoSelect(Instruction &Op, SelectInst *SI) {
VectorType *SrcTy = dyn_cast<VectorType>(BC->getSrcTy());
// Verify that either both or neither are vectors.
- if ((SrcTy == NULL) != (DestTy == NULL)) return 0;
+ if ((SrcTy == nullptr) != (DestTy == nullptr)) return nullptr;
// If vectors, verify that they have the same number of elements.
if (SrcTy && SrcTy->getNumElements() != DestTy->getNumElements())
- return 0;
+ return nullptr;
}
Value *SelectTrueVal = FoldOperationIntoSelectOperand(Op, TV, this);
@@ -623,7 +623,7 @@ Instruction *InstCombiner::FoldOpIntoSelect(Instruction &Op, SelectInst *SI) {
return SelectInst::Create(SI->getCondition(),
SelectTrueVal, SelectFalseVal);
}
- return 0;
+ return nullptr;
}
@@ -635,7 +635,7 @@ Instruction *InstCombiner::FoldOpIntoPhi(Instruction &I) {
PHINode *PN = cast<PHINode>(I.getOperand(0));
unsigned NumPHIValues = PN->getNumIncomingValues();
if (NumPHIValues == 0)
- return 0;
+ return nullptr;
// We normally only transform phis with a single use. However, if a PHI has
// multiple uses and they are all the same operation, we can fold *all* of the
@@ -645,7 +645,7 @@ Instruction *InstCombiner::FoldOpIntoPhi(Instruction &I) {
for (User *U : PN->users()) {
Instruction *UI = cast<Instruction>(U);
if (UI != &I && !I.isIdenticalTo(UI))
- return 0;
+ return nullptr;
}
// Otherwise, we can replace *all* users with the new PHI we form.
}
@@ -655,14 +655,14 @@ Instruction *InstCombiner::FoldOpIntoPhi(Instruction &I) {
// remember the BB it is in. If there is more than one or if *it* is a PHI,
// bail out. We don't do arbitrary constant expressions here because moving
// their computation can be expensive without a cost model.
- BasicBlock *NonConstBB = 0;
+ BasicBlock *NonConstBB = nullptr;
for (unsigned i = 0; i != NumPHIValues; ++i) {
Value *InVal = PN->getIncomingValue(i);
if (isa<Constant>(InVal) && !isa<ConstantExpr>(InVal))
continue;
- if (isa<PHINode>(InVal)) return 0; // Itself a phi.
- if (NonConstBB) return 0; // More than one non-const value.
+ if (isa<PHINode>(InVal)) return nullptr; // Itself a phi.
+ if (NonConstBB) return nullptr; // More than one non-const value.
NonConstBB = PN->getIncomingBlock(i);
@@ -670,22 +670,22 @@ Instruction *InstCombiner::FoldOpIntoPhi(Instruction &I) {
// insert a computation after it without breaking the edge.
if (InvokeInst *II = dyn_cast<InvokeInst>(InVal))
if (II->getParent() == NonConstBB)
- return 0;
+ return nullptr;
// If the incoming non-constant value is in I's block, we will remove one
// instruction, but insert another equivalent one, leading to infinite
// instcombine.
if (NonConstBB == I.getParent())
- return 0;
+ return nullptr;
}
// If there is exactly one non-constant value, we can insert a copy of the
// operation in that block. However, if this is a critical edge, we would be
// inserting the computation one some other paths (e.g. inside a loop). Only
// do this if the pred block is unconditionally branching into the phi block.
- if (NonConstBB != 0) {
+ if (NonConstBB != nullptr) {
BranchInst *BI = dyn_cast<BranchInst>(NonConstBB->getTerminator());
- if (!BI || !BI->isUnconditional()) return 0;
+ if (!BI || !BI->isUnconditional()) return nullptr;
}
// Okay, we can do the transformation: create the new PHI node.
@@ -709,7 +709,7 @@ Instruction *InstCombiner::FoldOpIntoPhi(Instruction &I) {
BasicBlock *ThisBB = PN->getIncomingBlock(i);
Value *TrueVInPred = TrueV->DoPHITranslation(PhiTransBB, ThisBB);
Value *FalseVInPred = FalseV->DoPHITranslation(PhiTransBB, ThisBB);
- Value *InV = 0;
+ Value *InV = nullptr;
// Beware of ConstantExpr: it may eventually evaluate to getNullValue,
// even if currently isNullValue gives false.
Constant *InC = dyn_cast<Constant>(PN->getIncomingValue(i));
@@ -723,7 +723,7 @@ Instruction *InstCombiner::FoldOpIntoPhi(Instruction &I) {
} else if (CmpInst *CI = dyn_cast<CmpInst>(&I)) {
Constant *C = cast<Constant>(I.getOperand(1));
for (unsigned i = 0; i != NumPHIValues; ++i) {
- Value *InV = 0;
+ Value *InV = nullptr;
if (Constant *InC = dyn_cast<Constant>(PN->getIncomingValue(i)))
InV = ConstantExpr::getCompare(CI->getPredicate(), InC, C);
else if (isa<ICmpInst>(CI))
@@ -737,7 +737,7 @@ Instruction *InstCombiner::FoldOpIntoPhi(Instruction &I) {
} else if (I.getNumOperands() == 2) {
Constant *C = cast<Constant>(I.getOperand(1));
for (unsigned i = 0; i != NumPHIValues; ++i) {
- Value *InV = 0;
+ Value *InV = nullptr;
if (Constant *InC = dyn_cast<Constant>(PN->getIncomingValue(i)))
InV = ConstantExpr::get(I.getOpcode(), InC, C);
else
@@ -777,11 +777,11 @@ Type *InstCombiner::FindElementAtOffset(Type *PtrTy, int64_t Offset,
assert(PtrTy->isPtrOrPtrVectorTy());
if (!DL)
- return 0;
+ return nullptr;
Type *Ty = PtrTy->getPointerElementType();
if (!Ty->isSized())
- return 0;
+ return nullptr;
// Start with the index over the outer type. Note that the type size
// might be zero (even if the offset isn't zero) if the indexed type
@@ -807,7 +807,7 @@ Type *InstCombiner::FindElementAtOffset(Type *PtrTy, int64_t Offset,
while (Offset) {
// Indexing into tail padding between struct/array elements.
if (uint64_t(Offset*8) >= DL->getTypeSizeInBits(Ty))
- return 0;
+ return nullptr;
if (StructType *STy = dyn_cast<StructType>(Ty)) {
const StructLayout *SL = DL->getStructLayout(STy);
@@ -828,7 +828,7 @@ Type *InstCombiner::FindElementAtOffset(Type *PtrTy, int64_t Offset,
Ty = AT->getElementType();
} else {
// Otherwise, we can't index into the middle of this atomic type, bail.
- return 0;
+ return nullptr;
}
}
@@ -860,7 +860,7 @@ Value *InstCombiner::Descale(Value *Val, APInt Scale, bool &NoSignedWrap) {
// If Scale is zero then it does not divide Val.
if (Scale.isMinValue())
- return 0;
+ return nullptr;
// Look through chains of multiplications, searching for a constant that is
// divisible by Scale. For example, descaling X*(Y*(Z*4)) by a factor of 4
@@ -903,7 +903,7 @@ Value *InstCombiner::Descale(Value *Val, APInt Scale, bool &NoSignedWrap) {
APInt::sdivrem(CI->getValue(), Scale, Quotient, Remainder);
if (!Remainder.isMinValue())
// Not divisible by Scale.
- return 0;
+ return nullptr;
// Replace with the quotient in the parent.
Op = ConstantInt::get(CI->getType(), Quotient);
NoSignedWrap = true;
@@ -916,7 +916,7 @@ Value *InstCombiner::Descale(Value *Val, APInt Scale, bool &NoSignedWrap) {
// Multiplication.
NoSignedWrap = BO->hasNoSignedWrap();
if (RequireNoSignedWrap && !NoSignedWrap)
- return 0;
+ return nullptr;
// There are three cases for multiplication: multiplication by exactly
// the scale, multiplication by a constant different to the scale, and
@@ -935,7 +935,7 @@ Value *InstCombiner::Descale(Value *Val, APInt Scale, bool &NoSignedWrap) {
// Otherwise drill down into the constant.
if (!Op->hasOneUse())
- return 0;
+ return nullptr;
Parent = std::make_pair(BO, 1);
continue;
@@ -944,7 +944,7 @@ Value *InstCombiner::Descale(Value *Val, APInt Scale, bool &NoSignedWrap) {
// Multiplication by something else. Drill down into the left-hand side
// since that's where the reassociate pass puts the good stuff.
if (!Op->hasOneUse())
- return 0;
+ return nullptr;
Parent = std::make_pair(BO, 0);
continue;
@@ -955,7 +955,7 @@ Value *InstCombiner::Descale(Value *Val, APInt Scale, bool &NoSignedWrap) {
// Multiplication by a power of 2.
NoSignedWrap = BO->hasNoSignedWrap();
if (RequireNoSignedWrap && !NoSignedWrap)
- return 0;
+ return nullptr;
Value *LHS = BO->getOperand(0);
int32_t Amt = cast<ConstantInt>(BO->getOperand(1))->
@@ -969,7 +969,7 @@ Value *InstCombiner::Descale(Value *Val, APInt Scale, bool &NoSignedWrap) {
break;
}
if (Amt < logScale || !Op->hasOneUse())
- return 0;
+ return nullptr;
// Multiplication by more than the scale. Reduce the multiplying amount
// by the scale in the parent.
@@ -980,7 +980,7 @@ Value *InstCombiner::Descale(Value *Val, APInt Scale, bool &NoSignedWrap) {
}
if (!Op->hasOneUse())
- return 0;
+ return nullptr;
if (CastInst *Cast = dyn_cast<CastInst>(Op)) {
if (Cast->getOpcode() == Instruction::SExt) {
@@ -994,7 +994,7 @@ Value *InstCombiner::Descale(Value *Val, APInt Scale, bool &NoSignedWrap) {
// Scale and the multiplication Y * SmallScale should not overflow.
if (SmallScale.sext(Scale.getBitWidth()) != Scale)
// SmallScale does not sign-extend to Scale.
- return 0;
+ return nullptr;
assert(SmallScale.exactLogBase2() == logScale);
// Require that Y * SmallScale must not overflow.
RequireNoSignedWrap = true;
@@ -1013,7 +1013,7 @@ Value *InstCombiner::Descale(Value *Val, APInt Scale, bool &NoSignedWrap) {
// trunc (Y * sext Scale) does not, so nsw flags need to be cleared
// from this point up in the expression (see later).
if (RequireNoSignedWrap)
- return 0;
+ return nullptr;
// Drill down through the cast.
unsigned LargeSize = Cast->getSrcTy()->getPrimitiveSizeInBits();
@@ -1027,7 +1027,7 @@ Value *InstCombiner::Descale(Value *Val, APInt Scale, bool &NoSignedWrap) {
}
// Unsupported expression, bail out.
- return 0;
+ return nullptr;
}
// We know that we can successfully descale, so from here on we can safely
@@ -1131,7 +1131,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
//
if (GEPOperator *Src = dyn_cast<GEPOperator>(PtrOp)) {
if (!shouldMergeGEPs(*cast<GEPOperator>(&GEP), *Src))
- return 0;
+ return nullptr;
// Note that if our source is a gep chain itself then we wait for that
// chain to be resolved before we perform this transformation. This
@@ -1139,7 +1139,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
if (GEPOperator *SrcGEP =
dyn_cast<GEPOperator>(Src->getOperand(0)))
if (SrcGEP->getNumOperands() == 2 && shouldMergeGEPs(*Src, *SrcGEP))
- return 0; // Wait until our source is folded to completion.
+ return nullptr; // Wait until our source is folded to completion.
SmallVector<Value*, 8> Indices;
@@ -1167,7 +1167,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
// intptr_t). Just avoid transforming this until the input has been
// normalized.
if (SO1->getType() != GO1->getType())
- return 0;
+ return nullptr;
Sum = Builder->CreateAdd(SO1, GO1, PtrOp->getName()+".sum");
}
@@ -1217,7 +1217,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
// We do not handle pointer-vector geps here.
if (!StrippedPtrTy)
- return 0;
+ return nullptr;
if (StrippedPtr != PtrOp) {
bool HasZeroPointerIndex = false;
@@ -1385,7 +1385,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
}
if (!DL)
- return 0;
+ return nullptr;
/// See if we can simplify:
/// X = bitcast A* to B*
@@ -1437,7 +1437,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
}
}
- return 0;
+ return nullptr;
}
static bool
@@ -1552,7 +1552,7 @@ Instruction *InstCombiner::visitAllocSite(Instruction &MI) {
}
return EraseInstFromFunction(MI);
}
- return 0;
+ return nullptr;
}
/// \brief Move the call to free before a NULL test.
@@ -1581,30 +1581,30 @@ tryToMoveFreeBeforeNullTest(CallInst &FI) {
// would duplicate the call to free in each predecessor and it may
// not be profitable even for code size.
if (!PredBB)
- return 0;
+ return nullptr;
// Validate constraint #2: Does this block contains only the call to
// free and an unconditional branch?
// FIXME: We could check if we can speculate everything in the
// predecessor block
if (FreeInstrBB->size() != 2)
- return 0;
+ return nullptr;
BasicBlock *SuccBB;
if (!match(FreeInstrBB->getTerminator(), m_UnconditionalBr(SuccBB)))
- return 0;
+ return nullptr;
// Validate the rest of constraint #1 by matching on the pred branch.
TerminatorInst *TI = PredBB->getTerminator();
BasicBlock *TrueBB, *FalseBB;
ICmpInst::Predicate Pred;
if (!match(TI, m_Br(m_ICmp(Pred, m_Specific(Op), m_Zero()), TrueBB, FalseBB)))
- return 0;
+ return nullptr;
if (Pred != ICmpInst::ICMP_EQ && Pred != ICmpInst::ICMP_NE)
- return 0;
+ return nullptr;
// Validate constraint #3: Ensure the null case just falls through.
if (SuccBB != (Pred == ICmpInst::ICMP_EQ ? TrueBB : FalseBB))
- return 0;
+ return nullptr;
assert(FreeInstrBB == (Pred == ICmpInst::ICMP_EQ ? FalseBB : TrueBB) &&
"Broken CFG: missing edge from predecessor to successor");
@@ -1639,14 +1639,14 @@ Instruction *InstCombiner::visitFree(CallInst &FI) {
if (Instruction *I = tryToMoveFreeBeforeNullTest(FI))
return I;
- return 0;
+ return nullptr;
}
Instruction *InstCombiner::visitBranchInst(BranchInst &BI) {
// Change br (not X), label True, label False to: br X, label False, True
- Value *X = 0;
+ Value *X = nullptr;
BasicBlock *TrueDest;
BasicBlock *FalseDest;
if (match(&BI, m_Br(m_Not(m_Value(X)), TrueDest, FalseDest)) &&
@@ -1689,7 +1689,7 @@ Instruction *InstCombiner::visitBranchInst(BranchInst &BI) {
return &BI;
}
- return 0;
+ return nullptr;
}
Instruction *InstCombiner::visitSwitchInst(SwitchInst &SI) {
@@ -1713,7 +1713,7 @@ Instruction *InstCombiner::visitSwitchInst(SwitchInst &SI) {
return &SI;
}
}
- return 0;
+ return nullptr;
}
Instruction *InstCombiner::visitExtractValueInst(ExtractValueInst &EV) {
@@ -1730,7 +1730,7 @@ Instruction *InstCombiner::visitExtractValueInst(ExtractValueInst &EV) {
// first index
return ExtractValueInst::Create(C2, EV.getIndices().slice(1));
}
- return 0; // Can't handle other constants
+ return nullptr; // Can't handle other constants
}
if (InsertValueInst *IV = dyn_cast<InsertValueInst>(Agg)) {
@@ -1863,7 +1863,7 @@ Instruction *InstCombiner::visitExtractValueInst(ExtractValueInst &EV) {
// and if again single-use then via load (gep (gep)) to load (gep).
// However, double extracts from e.g. function arguments or return values
// aren't handled yet.
- return 0;
+ return nullptr;
}
enum Personality_Type {
@@ -2202,7 +2202,7 @@ Instruction *InstCombiner::visitLandingPadInst(LandingPadInst &LI) {
return &LI;
}
- return 0;
+ return nullptr;
}
@@ -2295,7 +2295,7 @@ static bool AddReachableCodeToWorklist(BasicBlock *BB,
for (User::op_iterator i = Inst->op_begin(), e = Inst->op_end();
i != e; ++i) {
ConstantExpr *CE = dyn_cast<ConstantExpr>(i);
- if (CE == 0) continue;
+ if (CE == nullptr) continue;
Constant*& FoldRes = FoldedConstants[CE];
if (!FoldRes)
@@ -2399,7 +2399,7 @@ bool InstCombiner::DoOneIteration(Function &F, unsigned Iteration) {
while (!Worklist.isEmpty()) {
Instruction *I = Worklist.RemoveOne();
- if (I == 0) continue; // skip null values.
+ if (I == nullptr) continue; // skip null values.
// Check to see if we can DCE the instruction.
if (isInstructionTriviallyDead(I, TLI)) {
@@ -2541,7 +2541,7 @@ bool InstCombiner::runOnFunction(Function &F) {
return false;
DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>();
- DL = DLP ? &DLP->getDataLayout() : 0;
+ DL = DLP ? &DLP->getDataLayout() : nullptr;
TLI = &getAnalysis<TargetLibraryInfo>();
// Minimizing size?
MinimizeSize = F.getAttributes().hasAttribute(AttributeSet::FunctionIndex,
@@ -2568,7 +2568,7 @@ bool InstCombiner::runOnFunction(Function &F) {
while (DoOneIteration(F, Iteration++))
EverMadeChange = true;
- Builder = 0;
+ Builder = nullptr;
return EverMadeChange;
}
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