summaryrefslogtreecommitdiff
path: root/lib/Analysis/ScalarEvolution.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'lib/Analysis/ScalarEvolution.cpp')
-rw-r--r--lib/Analysis/ScalarEvolution.cpp129
1 files changed, 66 insertions, 63 deletions
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index fdb15629f4..089ca42ef6 100644
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -182,7 +182,7 @@ void SCEV::print(raw_ostream &OS) const {
case scUMaxExpr:
case scSMaxExpr: {
const SCEVNAryExpr *NAry = cast<SCEVNAryExpr>(this);
- const char *OpStr = 0;
+ const char *OpStr = nullptr;
switch (NAry->getSCEVType()) {
case scAddExpr: OpStr = " + "; break;
case scMulExpr: OpStr = " * "; break;
@@ -312,7 +312,7 @@ const SCEV *ScalarEvolution::getConstant(ConstantInt *V) {
FoldingSetNodeID ID;
ID.AddInteger(scConstant);
ID.AddPointer(V);
- void *IP = 0;
+ void *IP = nullptr;
if (const SCEV *S = UniqueSCEVs.FindNodeOrInsertPos(ID, IP)) return S;
SCEV *S = new (SCEVAllocator) SCEVConstant(ID.Intern(SCEVAllocator), V);
UniqueSCEVs.InsertNode(S, IP);
@@ -365,7 +365,7 @@ void SCEVUnknown::deleted() {
SE->UniqueSCEVs.RemoveNode(this);
// Release the value.
- setValPtr(0);
+ setValPtr(nullptr);
}
void SCEVUnknown::allUsesReplacedWith(Value *New) {
@@ -829,7 +829,7 @@ const SCEV *ScalarEvolution::getTruncateExpr(const SCEV *Op,
ID.AddInteger(scTruncate);
ID.AddPointer(Op);
ID.AddPointer(Ty);
- void *IP = 0;
+ void *IP = nullptr;
if (const SCEV *S = UniqueSCEVs.FindNodeOrInsertPos(ID, IP)) return S;
// Fold if the operand is constant.
@@ -919,7 +919,7 @@ const SCEV *ScalarEvolution::getZeroExtendExpr(const SCEV *Op,
ID.AddInteger(scZeroExtend);
ID.AddPointer(Op);
ID.AddPointer(Ty);
- void *IP = 0;
+ void *IP = nullptr;
if (const SCEV *S = UniqueSCEVs.FindNodeOrInsertPos(ID, IP)) return S;
// zext(trunc(x)) --> zext(x) or x or trunc(x)
@@ -1072,7 +1072,7 @@ static const SCEV *getOverflowLimitForStep(const SCEV *Step,
return SE->getConstant(APInt::getSignedMaxValue(BitWidth) -
SE->getSignedRange(Step).getSignedMin());
}
- return 0;
+ return nullptr;
}
// The recurrence AR has been shown to have no signed wrap. Typically, if we can
@@ -1091,7 +1091,7 @@ static const SCEV *getPreStartForSignExtend(const SCEVAddRecExpr *AR,
// Check for a simple looking step prior to loop entry.
const SCEVAddExpr *SA = dyn_cast<SCEVAddExpr>(Start);
if (!SA)
- return 0;
+ return nullptr;
// Create an AddExpr for "PreStart" after subtracting Step. Full SCEV
// subtraction is expensive. For this purpose, perform a quick and dirty
@@ -1103,7 +1103,7 @@ static const SCEV *getPreStartForSignExtend(const SCEVAddRecExpr *AR,
DiffOps.push_back(*I);
}
if (DiffOps.size() == SA->getNumOperands())
- return 0;
+ return nullptr;
// This is a postinc AR. Check for overflow on the preinc recurrence using the
// same three conditions that getSignExtendedExpr checks.
@@ -1139,7 +1139,7 @@ static const SCEV *getPreStartForSignExtend(const SCEVAddRecExpr *AR,
SE->isLoopEntryGuardedByCond(L, Pred, PreStart, OverflowLimit)) {
return PreStart;
}
- return 0;
+ return nullptr;
}
// Get the normalized sign-extended expression for this AddRec's Start.
@@ -1181,7 +1181,7 @@ const SCEV *ScalarEvolution::getSignExtendExpr(const SCEV *Op,
ID.AddInteger(scSignExtend);
ID.AddPointer(Op);
ID.AddPointer(Ty);
- void *IP = 0;
+ void *IP = nullptr;
if (const SCEV *S = UniqueSCEVs.FindNodeOrInsertPos(ID, IP)) return S;
// If the input value is provably positive, build a zext instead.
@@ -1811,7 +1811,7 @@ const SCEV *ScalarEvolution::getAddExpr(SmallVectorImpl<const SCEV *> &Ops,
ID.AddInteger(scAddExpr);
for (unsigned i = 0, e = Ops.size(); i != e; ++i)
ID.AddPointer(Ops[i]);
- void *IP = 0;
+ void *IP = nullptr;
SCEVAddExpr *S =
static_cast<SCEVAddExpr *>(UniqueSCEVs.FindNodeOrInsertPos(ID, IP));
if (!S) {
@@ -2105,7 +2105,7 @@ const SCEV *ScalarEvolution::getMulExpr(SmallVectorImpl<const SCEV *> &Ops,
ID.AddInteger(scMulExpr);
for (unsigned i = 0, e = Ops.size(); i != e; ++i)
ID.AddPointer(Ops[i]);
- void *IP = 0;
+ void *IP = nullptr;
SCEVMulExpr *S =
static_cast<SCEVMulExpr *>(UniqueSCEVs.FindNodeOrInsertPos(ID, IP));
if (!S) {
@@ -2230,7 +2230,7 @@ const SCEV *ScalarEvolution::getUDivExpr(const SCEV *LHS,
ID.AddInteger(scUDivExpr);
ID.AddPointer(LHS);
ID.AddPointer(RHS);
- void *IP = 0;
+ void *IP = nullptr;
if (const SCEV *S = UniqueSCEVs.FindNodeOrInsertPos(ID, IP)) return S;
SCEV *S = new (SCEVAllocator) SCEVUDivExpr(ID.Intern(SCEVAllocator),
LHS, RHS);
@@ -2425,7 +2425,7 @@ ScalarEvolution::getAddRecExpr(SmallVectorImpl<const SCEV *> &Operands,
for (unsigned i = 0, e = Operands.size(); i != e; ++i)
ID.AddPointer(Operands[i]);
ID.AddPointer(L);
- void *IP = 0;
+ void *IP = nullptr;
SCEVAddRecExpr *S =
static_cast<SCEVAddRecExpr *>(UniqueSCEVs.FindNodeOrInsertPos(ID, IP));
if (!S) {
@@ -2533,7 +2533,7 @@ ScalarEvolution::getSMaxExpr(SmallVectorImpl<const SCEV *> &Ops) {
ID.AddInteger(scSMaxExpr);
for (unsigned i = 0, e = Ops.size(); i != e; ++i)
ID.AddPointer(Ops[i]);
- void *IP = 0;
+ void *IP = nullptr;
if (const SCEV *S = UniqueSCEVs.FindNodeOrInsertPos(ID, IP)) return S;
const SCEV **O = SCEVAllocator.Allocate<const SCEV *>(Ops.size());
std::uninitialized_copy(Ops.begin(), Ops.end(), O);
@@ -2637,7 +2637,7 @@ ScalarEvolution::getUMaxExpr(SmallVectorImpl<const SCEV *> &Ops) {
ID.AddInteger(scUMaxExpr);
for (unsigned i = 0, e = Ops.size(); i != e; ++i)
ID.AddPointer(Ops[i]);
- void *IP = 0;
+ void *IP = nullptr;
if (const SCEV *S = UniqueSCEVs.FindNodeOrInsertPos(ID, IP)) return S;
const SCEV **O = SCEVAllocator.Allocate<const SCEV *>(Ops.size());
std::uninitialized_copy(Ops.begin(), Ops.end(), O);
@@ -2704,7 +2704,7 @@ const SCEV *ScalarEvolution::getUnknown(Value *V) {
FoldingSetNodeID ID;
ID.AddInteger(scUnknown);
ID.AddPointer(V);
- void *IP = 0;
+ void *IP = nullptr;
if (SCEV *S = UniqueSCEVs.FindNodeOrInsertPos(ID, IP)) {
assert(cast<SCEVUnknown>(S)->getValue() == V &&
"Stale SCEVUnknown in uniquing map!");
@@ -3010,7 +3010,7 @@ const SCEV *ScalarEvolution::getPointerBase(const SCEV *V) {
return getPointerBase(Cast->getOperand());
}
else if (const SCEVNAryExpr *NAry = dyn_cast<SCEVNAryExpr>(V)) {
- const SCEV *PtrOp = 0;
+ const SCEV *PtrOp = nullptr;
for (SCEVNAryExpr::op_iterator I = NAry->op_begin(), E = NAry->op_end();
I != E; ++I) {
if ((*I)->getType()->isPointerTy()) {
@@ -3090,20 +3090,20 @@ const SCEV *ScalarEvolution::createNodeForPHI(PHINode *PN) {
// The loop may have multiple entrances or multiple exits; we can analyze
// this phi as an addrec if it has a unique entry value and a unique
// backedge value.
- Value *BEValueV = 0, *StartValueV = 0;
+ Value *BEValueV = nullptr, *StartValueV = nullptr;
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
Value *V = PN->getIncomingValue(i);
if (L->contains(PN->getIncomingBlock(i))) {
if (!BEValueV) {
BEValueV = V;
} else if (BEValueV != V) {
- BEValueV = 0;
+ BEValueV = nullptr;
break;
}
} else if (!StartValueV) {
StartValueV = V;
} else if (StartValueV != V) {
- StartValueV = 0;
+ StartValueV = nullptr;
break;
}
}
@@ -4316,9 +4316,9 @@ ScalarEvolution::BackedgeTakenInfo::getExact(ScalarEvolution *SE) const {
if (!ExitNotTaken.ExitingBlock) return SE->getCouldNotCompute();
assert(ExitNotTaken.ExactNotTaken && "uninitialized not-taken info");
- const SCEV *BECount = 0;
+ const SCEV *BECount = nullptr;
for (const ExitNotTakenInfo *ENT = &ExitNotTaken;
- ENT != 0; ENT = ENT->getNextExit()) {
+ ENT != nullptr; ENT = ENT->getNextExit()) {
assert(ENT->ExactNotTaken != SE->getCouldNotCompute() && "bad exit SCEV");
@@ -4336,7 +4336,7 @@ const SCEV *
ScalarEvolution::BackedgeTakenInfo::getExact(BasicBlock *ExitingBlock,
ScalarEvolution *SE) const {
for (const ExitNotTakenInfo *ENT = &ExitNotTaken;
- ENT != 0; ENT = ENT->getNextExit()) {
+ ENT != nullptr; ENT = ENT->getNextExit()) {
if (ENT->ExitingBlock == ExitingBlock)
return ENT->ExactNotTaken;
@@ -4359,7 +4359,7 @@ bool ScalarEvolution::BackedgeTakenInfo::hasOperand(const SCEV *S,
return false;
for (const ExitNotTakenInfo *ENT = &ExitNotTaken;
- ENT != 0; ENT = ENT->getNextExit()) {
+ ENT != nullptr; ENT = ENT->getNextExit()) {
if (ENT->ExactNotTaken != SE->getCouldNotCompute()
&& SE->hasOperand(ENT->ExactNotTaken, S)) {
@@ -4398,8 +4398,8 @@ ScalarEvolution::BackedgeTakenInfo::BackedgeTakenInfo(
/// clear - Invalidate this result and free the ExitNotTakenInfo array.
void ScalarEvolution::BackedgeTakenInfo::clear() {
- ExitNotTaken.ExitingBlock = 0;
- ExitNotTaken.ExactNotTaken = 0;
+ ExitNotTaken.ExitingBlock = nullptr;
+ ExitNotTaken.ExactNotTaken = nullptr;
delete[] ExitNotTaken.getNextExit();
}
@@ -4414,7 +4414,7 @@ ScalarEvolution::ComputeBackedgeTakenCount(const Loop *L) {
const SCEV *MaxBECount = getCouldNotCompute();
bool CouldComputeBECount = true;
BasicBlock *Latch = L->getLoopLatch(); // may be NULL.
- const SCEV *LatchMaxCount = 0;
+ const SCEV *LatchMaxCount = nullptr;
SmallVector<std::pair<BasicBlock *, const SCEV *>, 4> ExitCounts;
for (unsigned i = 0, e = ExitingBlocks.size(); i != e; ++i) {
ExitLimit EL = ComputeExitLimit(L, ExitingBlocks[i]);
@@ -4454,7 +4454,7 @@ ScalarEvolution::ComputeExitLimit(const Loop *L, BasicBlock *ExitingBlock) {
// exit at this block and remember the exit block and whether all other targets
// lead to the loop header.
bool MustExecuteLoopHeader = true;
- BasicBlock *Exit = 0;
+ BasicBlock *Exit = nullptr;
for (succ_iterator SI = succ_begin(ExitingBlock), SE = succ_end(ExitingBlock);
SI != SE; ++SI)
if (!L->contains(*SI)) {
@@ -4800,7 +4800,7 @@ ScalarEvolution::ComputeLoadConstantCompareExitLimit(
return getCouldNotCompute();
// Okay, we allow one non-constant index into the GEP instruction.
- Value *VarIdx = 0;
+ Value *VarIdx = nullptr;
std::vector<Constant*> Indexes;
unsigned VarIdxNum = 0;
for (unsigned i = 2, e = GEP->getNumOperands(); i != e; ++i)
@@ -4810,7 +4810,7 @@ ScalarEvolution::ComputeLoadConstantCompareExitLimit(
if (VarIdx) return getCouldNotCompute(); // Multiple non-constant idx's.
VarIdx = GEP->getOperand(i);
VarIdxNum = i-2;
- Indexes.push_back(0);
+ Indexes.push_back(nullptr);
}
// Loop-invariant loads may be a byproduct of loop optimization. Skip them.
@@ -4841,7 +4841,7 @@ ScalarEvolution::ComputeLoadConstantCompareExitLimit(
Constant *Result = ConstantFoldLoadThroughGEPIndices(GV->getInitializer(),
Indexes);
- if (Result == 0) break; // Cannot compute!
+ if (!Result) break; // Cannot compute!
// Evaluate the condition for this iteration.
Result = ConstantExpr::getICmp(predicate, Result, RHS);
@@ -4902,14 +4902,14 @@ getConstantEvolvingPHIOperands(Instruction *UseInst, const Loop *L,
// Otherwise, we can evaluate this instruction if all of its operands are
// constant or derived from a PHI node themselves.
- PHINode *PHI = 0;
+ PHINode *PHI = nullptr;
for (Instruction::op_iterator OpI = UseInst->op_begin(),
OpE = UseInst->op_end(); OpI != OpE; ++OpI) {
if (isa<Constant>(*OpI)) continue;
Instruction *OpInst = dyn_cast<Instruction>(*OpI);
- if (!OpInst || !canConstantEvolve(OpInst, L)) return 0;
+ if (!OpInst || !canConstantEvolve(OpInst, L)) return nullptr;
PHINode *P = dyn_cast<PHINode>(OpInst);
if (!P)
@@ -4923,8 +4923,10 @@ getConstantEvolvingPHIOperands(Instruction *UseInst, const Loop *L,
P = getConstantEvolvingPHIOperands(OpInst, L, PHIMap);
PHIMap[OpInst] = P;
}
- if (P == 0) return 0; // Not evolving from PHI
- if (PHI && PHI != P) return 0; // Evolving from multiple different PHIs.
+ if (!P)
+ return nullptr; // Not evolving from PHI
+ if (PHI && PHI != P)
+ return nullptr; // Evolving from multiple different PHIs.
PHI = P;
}
// This is a expression evolving from a constant PHI!
@@ -4938,7 +4940,7 @@ getConstantEvolvingPHIOperands(Instruction *UseInst, const Loop *L,
/// constraints, return null.
static PHINode *getConstantEvolvingPHI(Value *V, const Loop *L) {
Instruction *I = dyn_cast<Instruction>(V);
- if (I == 0 || !canConstantEvolve(I, L)) return 0;
+ if (!I || !canConstantEvolve(I, L)) return nullptr;
if (PHINode *PN = dyn_cast<PHINode>(I)) {
return PN;
@@ -4960,18 +4962,18 @@ static Constant *EvaluateExpression(Value *V, const Loop *L,
// Convenient constant check, but redundant for recursive calls.
if (Constant *C = dyn_cast<Constant>(V)) return C;
Instruction *I = dyn_cast<Instruction>(V);
- if (!I) return 0;
+ if (!I) return nullptr;
if (Constant *C = Vals.lookup(I)) return C;
// An instruction inside the loop depends on a value outside the loop that we
// weren't given a mapping for, or a value such as a call inside the loop.
- if (!canConstantEvolve(I, L)) return 0;
+ if (!canConstantEvolve(I, L)) return nullptr;
// An unmapped PHI can be due to a branch or another loop inside this loop,
// or due to this not being the initial iteration through a loop where we
// couldn't compute the evolution of this particular PHI last time.
- if (isa<PHINode>(I)) return 0;
+ if (isa<PHINode>(I)) return nullptr;
std::vector<Constant*> Operands(I->getNumOperands());
@@ -4979,12 +4981,12 @@ static Constant *EvaluateExpression(Value *V, const Loop *L,
Instruction *Operand = dyn_cast<Instruction>(I->getOperand(i));
if (!Operand) {
Operands[i] = dyn_cast<Constant>(I->getOperand(i));
- if (!Operands[i]) return 0;
+ if (!Operands[i]) return nullptr;
continue;
}
Constant *C = EvaluateExpression(Operand, L, Vals, DL, TLI);
Vals[Operand] = C;
- if (!C) return 0;
+ if (!C) return nullptr;
Operands[i] = C;
}
@@ -5013,7 +5015,7 @@ ScalarEvolution::getConstantEvolutionLoopExitValue(PHINode *PN,
return I->second;
if (BEs.ugt(MaxBruteForceIterations))
- return ConstantEvolutionLoopExitValue[PN] = 0; // Not going to evaluate it.
+ return ConstantEvolutionLoopExitValue[PN] = nullptr; // Not going to evaluate it.
Constant *&RetVal = ConstantEvolutionLoopExitValue[PN];
@@ -5025,22 +5027,22 @@ ScalarEvolution::getConstantEvolutionLoopExitValue(PHINode *PN,
// entry must be a constant (coming in from outside of the loop), and the
// second must be derived from the same PHI.
bool SecondIsBackedge = L->contains(PN->getIncomingBlock(1));
- PHINode *PHI = 0;
+ PHINode *PHI = nullptr;
for (BasicBlock::iterator I = Header->begin();
(PHI = dyn_cast<PHINode>(I)); ++I) {
Constant *StartCST =
dyn_cast<Constant>(PHI->getIncomingValue(!SecondIsBackedge));
- if (StartCST == 0) continue;
+ if (!StartCST) continue;
CurrentIterVals[PHI] = StartCST;
}
if (!CurrentIterVals.count(PN))
- return RetVal = 0;
+ return RetVal = nullptr;
Value *BEValue = PN->getIncomingValue(SecondIsBackedge);
// Execute the loop symbolically to determine the exit value.
if (BEs.getActiveBits() >= 32)
- return RetVal = 0; // More than 2^32-1 iterations?? Not doing it!
+ return RetVal = nullptr; // More than 2^32-1 iterations?? Not doing it!
unsigned NumIterations = BEs.getZExtValue(); // must be in range
unsigned IterationNum = 0;
@@ -5053,8 +5055,8 @@ ScalarEvolution::getConstantEvolutionLoopExitValue(PHINode *PN,
DenseMap<Instruction *, Constant *> NextIterVals;
Constant *NextPHI = EvaluateExpression(BEValue, L, CurrentIterVals, DL,
TLI);
- if (NextPHI == 0)
- return 0; // Couldn't evaluate!
+ if (!NextPHI)
+ return nullptr; // Couldn't evaluate!
NextIterVals[PN] = NextPHI;
bool StoppedEvolving = NextPHI == CurrentIterVals[PN];
@@ -5101,7 +5103,7 @@ const SCEV *ScalarEvolution::ComputeExitCountExhaustively(const Loop *L,
Value *Cond,
bool ExitWhen) {
PHINode *PN = getConstantEvolvingPHI(Cond, L);
- if (PN == 0) return getCouldNotCompute();
+ if (!PN) return getCouldNotCompute();
// If the loop is canonicalized, the PHI will have exactly two entries.
// That's the only form we support here.
@@ -5114,12 +5116,12 @@ const SCEV *ScalarEvolution::ComputeExitCountExhaustively(const Loop *L,
// One entry must be a constant (coming in from outside of the loop), and the
// second must be derived from the same PHI.
bool SecondIsBackedge = L->contains(PN->getIncomingBlock(1));
- PHINode *PHI = 0;
+ PHINode *PHI = nullptr;
for (BasicBlock::iterator I = Header->begin();
(PHI = dyn_cast<PHINode>(I)); ++I) {
Constant *StartCST =
dyn_cast<Constant>(PHI->getIncomingValue(!SecondIsBackedge));
- if (StartCST == 0) continue;
+ if (!StartCST) continue;
CurrentIterVals[PHI] = StartCST;
}
if (!CurrentIterVals.count(PN))
@@ -5189,7 +5191,7 @@ const SCEV *ScalarEvolution::getSCEVAtScope(const SCEV *V, const Loop *L) {
if (Values[u].first == L)
return Values[u].second ? Values[u].second : V;
}
- Values.push_back(std::make_pair(L, static_cast<const SCEV *>(0)));
+ Values.push_back(std::make_pair(L, static_cast<const SCEV *>(nullptr)));
// Otherwise compute it.
const SCEV *C = computeSCEVAtScope(V, L);
SmallVector<std::pair<const Loop *, const SCEV *>, 2> &Values2 = ValuesAtScopes[V];
@@ -5243,7 +5245,7 @@ static Constant *BuildConstantFromSCEV(const SCEV *V) {
}
for (unsigned i = 1, e = SA->getNumOperands(); i != e; ++i) {
Constant *C2 = BuildConstantFromSCEV(SA->getOperand(i));
- if (!C2) return 0;
+ if (!C2) return nullptr;
// First pointer!
if (!C->getType()->isPointerTy() && C2->getType()->isPointerTy()) {
@@ -5258,7 +5260,7 @@ static Constant *BuildConstantFromSCEV(const SCEV *V) {
// Don't bother trying to sum two pointers. We probably can't
// statically compute a load that results from it anyway.
if (C2->getType()->isPointerTy())
- return 0;
+ return nullptr;
if (PointerType *PTy = dyn_cast<PointerType>(C->getType())) {
if (PTy->getElementType()->isStructTy())
@@ -5276,10 +5278,10 @@ static Constant *BuildConstantFromSCEV(const SCEV *V) {
const SCEVMulExpr *SM = cast<SCEVMulExpr>(V);
if (Constant *C = BuildConstantFromSCEV(SM->getOperand(0))) {
// Don't bother with pointers at all.
- if (C->getType()->isPointerTy()) return 0;
+ if (C->getType()->isPointerTy()) return nullptr;
for (unsigned i = 1, e = SM->getNumOperands(); i != e; ++i) {
Constant *C2 = BuildConstantFromSCEV(SM->getOperand(i));
- if (!C2 || C2->getType()->isPointerTy()) return 0;
+ if (!C2 || C2->getType()->isPointerTy()) return nullptr;
C = ConstantExpr::getMul(C, C2);
}
return C;
@@ -5298,7 +5300,7 @@ static Constant *BuildConstantFromSCEV(const SCEV *V) {
case scUMaxExpr:
break; // TODO: smax, umax.
}
- return 0;
+ return nullptr;
}
const SCEV *ScalarEvolution::computeSCEVAtScope(const SCEV *V, const Loop *L) {
@@ -5365,7 +5367,7 @@ const SCEV *ScalarEvolution::computeSCEVAtScope(const SCEV *V, const Loop *L) {
// Check to see if getSCEVAtScope actually made an improvement.
if (MadeImprovement) {
- Constant *C = 0;
+ Constant *C = nullptr;
if (const CmpInst *CI = dyn_cast<CmpInst>(I))
C = ConstantFoldCompareInstOperands(CI->getPredicate(),
Operands[0], Operands[1], DL,
@@ -5697,7 +5699,7 @@ ScalarEvolution::HowFarToZero(const SCEV *V, const Loop *L, bool IsSubExpr) {
// to 0, it must be counting down to equal 0. Consequently, N = Start / -Step.
// We have not yet seen any such cases.
const SCEVConstant *StepC = dyn_cast<SCEVConstant>(Step);
- if (StepC == 0 || StepC->getValue()->equalsInt(0))
+ if (!StepC || StepC->getValue()->equalsInt(0))
return getCouldNotCompute();
// For positive steps (counting up until unsigned overflow):
@@ -7375,7 +7377,8 @@ ScalarEvolution::SCEVCallbackVH::SCEVCallbackVH(Value *V, ScalarEvolution *se)
//===----------------------------------------------------------------------===//
ScalarEvolution::ScalarEvolution()
- : FunctionPass(ID), ValuesAtScopes(64), LoopDispositions(64), BlockDispositions(64), FirstUnknown(0) {
+ : FunctionPass(ID), ValuesAtScopes(64), LoopDispositions(64),
+ BlockDispositions(64), FirstUnknown(nullptr) {
initializeScalarEvolutionPass(*PassRegistry::getPassRegistry());
}
@@ -7383,7 +7386,7 @@ bool ScalarEvolution::runOnFunction(Function &F) {
this->F = &F;
LI = &getAnalysis<LoopInfo>();
DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>();
- DL = DLP ? &DLP->getDataLayout() : 0;
+ DL = DLP ? &DLP->getDataLayout() : nullptr;
TLI = &getAnalysis<TargetLibraryInfo>();
DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
return false;
@@ -7394,7 +7397,7 @@ void ScalarEvolution::releaseMemory() {
// destructors, so that they release their references to their values.
for (SCEVUnknown *U = FirstUnknown; U; U = U->Next)
U->~SCEVUnknown();
- FirstUnknown = 0;
+ FirstUnknown = nullptr;
ValueExprMap.clear();