23 changes: 11 additions & 12 deletions llvm/lib/IR/Verifier.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2210,24 +2210,23 @@ void Verifier::visitBasicBlock(BasicBlock &BB) {
SmallVector<BasicBlock*, 8> Preds(pred_begin(&BB), pred_end(&BB));
SmallVector<std::pair<BasicBlock*, Value*>, 8> Values;
std::sort(Preds.begin(), Preds.end());
PHINode *PN;
for (BasicBlock::iterator I = BB.begin(); (PN = dyn_cast<PHINode>(I));++I) {
for (const PHINode &PN : BB.phis()) {
// Ensure that PHI nodes have at least one entry!
Assert(PN->getNumIncomingValues() != 0,
Assert(PN.getNumIncomingValues() != 0,
"PHI nodes must have at least one entry. If the block is dead, "
"the PHI should be removed!",
PN);
Assert(PN->getNumIncomingValues() == Preds.size(),
&PN);
Assert(PN.getNumIncomingValues() == Preds.size(),
"PHINode should have one entry for each predecessor of its "
"parent basic block!",
PN);
&PN);

// Get and sort all incoming values in the PHI node...
Values.clear();
Values.reserve(PN->getNumIncomingValues());
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
Values.push_back(std::make_pair(PN->getIncomingBlock(i),
PN->getIncomingValue(i)));
Values.reserve(PN.getNumIncomingValues());
for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i)
Values.push_back(
std::make_pair(PN.getIncomingBlock(i), PN.getIncomingValue(i)));
std::sort(Values.begin(), Values.end());

for (unsigned i = 0, e = Values.size(); i != e; ++i) {
Expand All @@ -2239,12 +2238,12 @@ void Verifier::visitBasicBlock(BasicBlock &BB) {
Values[i].second == Values[i - 1].second,
"PHI node has multiple entries for the same basic block with "
"different incoming values!",
PN, Values[i].first, Values[i].second, Values[i - 1].second);
&PN, Values[i].first, Values[i].second, Values[i - 1].second);

// Check to make sure that the predecessors and PHI node entries are
// matched up.
Assert(Values[i].first == Preds[i],
"PHI node entries do not match predecessors!", PN,
"PHI node entries do not match predecessors!", &PN,
Values[i].first, Preds[i]);
}
}
Expand Down
11 changes: 4 additions & 7 deletions llvm/lib/Target/Hexagon/HexagonLoopIdiomRecognition.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1050,14 +1050,11 @@ bool PolynomialMultiplyRecognize::promoteTypes(BasicBlock *LoopB,
// Check if the exit values have types that are no wider than the type
// that we want to promote to.
unsigned DestBW = DestTy->getBitWidth();
for (Instruction &In : *ExitB) {
PHINode *P = dyn_cast<PHINode>(&In);
if (!P)
break;
if (P->getNumIncomingValues() != 1)
for (PHINode &P : ExitB->phis()) {
if (P.getNumIncomingValues() != 1)
return false;
assert(P->getIncomingBlock(0) == LoopB);
IntegerType *T = dyn_cast<IntegerType>(P->getType());
assert(P.getIncomingBlock(0) == LoopB);
IntegerType *T = dyn_cast<IntegerType>(P.getType());
if (!T || T->getBitWidth() > DestBW)
return false;
}
Expand Down
8 changes: 3 additions & 5 deletions llvm/lib/Transforms/Coroutines/CoroSplit.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -440,16 +440,14 @@ static void
scanPHIsAndUpdateValueMap(Instruction *Prev, BasicBlock *NewBlock,
DenseMap<Value *, Value *> &ResolvedValues) {
auto *PrevBB = Prev->getParent();
auto *I = &*NewBlock->begin();
while (auto PN = dyn_cast<PHINode>(I)) {
auto V = PN->getIncomingValueForBlock(PrevBB);
for (PHINode &PN : NewBlock->phis()) {
auto V = PN.getIncomingValueForBlock(PrevBB);
// See if we already resolved it.
auto VI = ResolvedValues.find(V);
if (VI != ResolvedValues.end())
V = VI->second;
// Remember the value.
ResolvedValues[PN] = V;
I = I->getNextNode();
ResolvedValues[&PN] = V;
}
}

Expand Down
11 changes: 4 additions & 7 deletions llvm/lib/Transforms/Scalar/CallSiteSplitting.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -265,15 +265,12 @@ static void splitCallSite(CallSite CS, BasicBlock *PredBB1, BasicBlock *PredBB2,
CallSite CS2(CallInst2);

// Handle PHIs used as arguments in the call-site.
for (auto &PI : *TailBB) {
PHINode *PN = dyn_cast<PHINode>(&PI);
if (!PN)
break;
for (PHINode &PN : TailBB->phis()) {
unsigned ArgNo = 0;
for (auto &CI : CS.args()) {
if (&*CI == PN) {
CS1.setArgument(ArgNo, PN->getIncomingValueForBlock(SplitBlock1));
CS2.setArgument(ArgNo, PN->getIncomingValueForBlock(SplitBlock2));
if (&*CI == &PN) {
CS1.setArgument(ArgNo, PN.getIncomingValueForBlock(SplitBlock1));
CS2.setArgument(ArgNo, PN.getIncomingValueForBlock(SplitBlock2));
}
++ArgNo;
}
Expand Down
8 changes: 2 additions & 6 deletions llvm/lib/Transforms/Scalar/GVNSink.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -592,12 +592,8 @@ class GVNSink {
/// Create a ModelledPHI for each PHI in BB, adding to PHIs.
void analyzeInitialPHIs(BasicBlock *BB, ModelledPHISet &PHIs,
SmallPtrSetImpl<Value *> &PHIContents) {
for (auto &I : *BB) {
auto *PN = dyn_cast<PHINode>(&I);
if (!PN)
return;

auto MPHI = ModelledPHI(PN);
for (PHINode &PN : BB->phis()) {
auto MPHI = ModelledPHI(&PN);
PHIs.insert(MPHI);
for (auto *V : MPHI.getValues())
PHIContents.insert(V);
Expand Down
21 changes: 9 additions & 12 deletions llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -485,9 +485,8 @@ void IndVarSimplify::rewriteNonIntegerIVs(Loop *L) {
BasicBlock *Header = L->getHeader();

SmallVector<WeakTrackingVH, 8> PHIs;
for (BasicBlock::iterator I = Header->begin();
PHINode *PN = dyn_cast<PHINode>(I); ++I)
PHIs.push_back(PN);
for (PHINode &PN : Header->phis())
PHIs.push_back(&PN);

for (unsigned i = 0, e = PHIs.size(); i != e; ++i)
if (PHINode *PN = dyn_cast_or_null<PHINode>(&*PHIs[i]))
Expand Down Expand Up @@ -724,13 +723,12 @@ void IndVarSimplify::rewriteFirstIterationLoopExitValues(Loop *L) {
assert(LoopHeader && "Invalid loop");

for (auto *ExitBB : ExitBlocks) {
BasicBlock::iterator BBI = ExitBB->begin();
// If there are no more PHI nodes in this exit block, then no more
// values defined inside the loop are used on this path.
while (auto *PN = dyn_cast<PHINode>(BBI++)) {
for (unsigned IncomingValIdx = 0, E = PN->getNumIncomingValues();
IncomingValIdx != E; ++IncomingValIdx) {
auto *IncomingBB = PN->getIncomingBlock(IncomingValIdx);
for (PHINode &PN : ExitBB->phis()) {
for (unsigned IncomingValIdx = 0, E = PN.getNumIncomingValues();
IncomingValIdx != E; ++IncomingValIdx) {
auto *IncomingBB = PN.getIncomingBlock(IncomingValIdx);

// We currently only support loop exits from loop header. If the
// incoming block is not loop header, we need to recursively check
Expand All @@ -755,8 +753,7 @@ void IndVarSimplify::rewriteFirstIterationLoopExitValues(Loop *L) {
if (!L->isLoopInvariant(Cond))
continue;

auto *ExitVal =
dyn_cast<PHINode>(PN->getIncomingValue(IncomingValIdx));
auto *ExitVal = dyn_cast<PHINode>(PN.getIncomingValue(IncomingValIdx));

// Only deal with PHIs.
if (!ExitVal)
Expand All @@ -771,8 +768,8 @@ void IndVarSimplify::rewriteFirstIterationLoopExitValues(Loop *L) {
if (PreheaderIdx != -1) {
assert(ExitVal->getParent() == LoopHeader &&
"ExitVal must be in loop header");
PN->setIncomingValue(IncomingValIdx,
ExitVal->getIncomingValue(PreheaderIdx));
PN.setIncomingValue(IncomingValIdx,
ExitVal->getIncomingValue(PreheaderIdx));
}
}
}
Expand Down
54 changes: 16 additions & 38 deletions llvm/lib/Transforms/Scalar/InductiveRangeCheckElimination.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1174,13 +1174,9 @@ void LoopConstrainer::cloneLoop(LoopConstrainer::ClonedLoop &Result,
if (OriginalLoop.contains(SBB))
continue; // not an exit block

for (Instruction &I : *SBB) {
auto *PN = dyn_cast<PHINode>(&I);
if (!PN)
break;

Value *OldIncoming = PN->getIncomingValueForBlock(OriginalBB);
PN->addIncoming(GetClonedValue(OldIncoming), ClonedBB);
for (PHINode &PN : SBB->phis()) {
Value *OldIncoming = PN.getIncomingValueForBlock(OriginalBB);
PN.addIncoming(GetClonedValue(OldIncoming), ClonedBB);
}
}
}
Expand Down Expand Up @@ -1327,16 +1323,12 @@ LoopConstrainer::RewrittenRangeInfo LoopConstrainer::changeIterationSpaceEnd(
// We emit PHI nodes into `RRI.PseudoExit' that compute the "latest" value of
// each of the PHI nodes in the loop header. This feeds into the initial
// value of the same PHI nodes if/when we continue execution.
for (Instruction &I : *LS.Header) {
auto *PN = dyn_cast<PHINode>(&I);
if (!PN)
break;

PHINode *NewPHI = PHINode::Create(PN->getType(), 2, PN->getName() + ".copy",
for (PHINode &PN : LS.Header->phis()) {
PHINode *NewPHI = PHINode::Create(PN.getType(), 2, PN.getName() + ".copy",
BranchToContinuation);

NewPHI->addIncoming(PN->getIncomingValueForBlock(Preheader), Preheader);
NewPHI->addIncoming(PN->getIncomingValueForBlock(LS.Latch),
NewPHI->addIncoming(PN.getIncomingValueForBlock(Preheader), Preheader);
NewPHI->addIncoming(PN.getIncomingValueForBlock(LS.Latch),
RRI.ExitSelector);
RRI.PHIValuesAtPseudoExit.push_back(NewPHI);
}
Expand All @@ -1348,12 +1340,8 @@ LoopConstrainer::RewrittenRangeInfo LoopConstrainer::changeIterationSpaceEnd(

// The latch exit now has a branch from `RRI.ExitSelector' instead of
// `LS.Latch'. The PHI nodes need to be updated to reflect that.
for (Instruction &I : *LS.LatchExit) {
if (PHINode *PN = dyn_cast<PHINode>(&I))
replacePHIBlock(PN, LS.Latch, RRI.ExitSelector);
else
break;
}
for (PHINode &PN : LS.LatchExit->phis())
replacePHIBlock(&PN, LS.Latch, RRI.ExitSelector);

return RRI;
}
Expand All @@ -1362,15 +1350,10 @@ void LoopConstrainer::rewriteIncomingValuesForPHIs(
LoopStructure &LS, BasicBlock *ContinuationBlock,
const LoopConstrainer::RewrittenRangeInfo &RRI) const {
unsigned PHIIndex = 0;
for (Instruction &I : *LS.Header) {
auto *PN = dyn_cast<PHINode>(&I);
if (!PN)
break;

for (unsigned i = 0, e = PN->getNumIncomingValues(); i < e; ++i)
if (PN->getIncomingBlock(i) == ContinuationBlock)
PN->setIncomingValue(i, RRI.PHIValuesAtPseudoExit[PHIIndex++]);
}
for (PHINode &PN : LS.Header->phis())
for (unsigned i = 0, e = PN.getNumIncomingValues(); i < e; ++i)
if (PN.getIncomingBlock(i) == ContinuationBlock)
PN.setIncomingValue(i, RRI.PHIValuesAtPseudoExit[PHIIndex++]);

LS.IndVarStart = RRI.IndVarEnd;
}
Expand All @@ -1381,14 +1364,9 @@ BasicBlock *LoopConstrainer::createPreheader(const LoopStructure &LS,
BasicBlock *Preheader = BasicBlock::Create(Ctx, Tag, &F, LS.Header);
BranchInst::Create(LS.Header, Preheader);

for (Instruction &I : *LS.Header) {
auto *PN = dyn_cast<PHINode>(&I);
if (!PN)
break;

for (unsigned i = 0, e = PN->getNumIncomingValues(); i < e; ++i)
replacePHIBlock(PN, OldPreheader, Preheader);
}
for (PHINode &PN : LS.Header->phis())
for (unsigned i = 0, e = PN.getNumIncomingValues(); i < e; ++i)
replacePHIBlock(&PN, OldPreheader, Preheader);

return Preheader;
}
Expand Down
7 changes: 3 additions & 4 deletions llvm/lib/Transforms/Scalar/JumpThreading.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1800,11 +1800,10 @@ static void AddPHINodeEntriesForMappedBlock(BasicBlock *PHIBB,
BasicBlock *OldPred,
BasicBlock *NewPred,
DenseMap<Instruction*, Value*> &ValueMap) {
for (BasicBlock::iterator PNI = PHIBB->begin();
PHINode *PN = dyn_cast<PHINode>(PNI); ++PNI) {
for (PHINode &PN : PHIBB->phis()) {
// Ok, we have a PHI node. Figure out what the incoming value was for the
// DestBlock.
Value *IV = PN->getIncomingValueForBlock(OldPred);
Value *IV = PN.getIncomingValueForBlock(OldPred);

// Remap the value if necessary.
if (Instruction *Inst = dyn_cast<Instruction>(IV)) {
Expand All @@ -1813,7 +1812,7 @@ static void AddPHINodeEntriesForMappedBlock(BasicBlock *PHIBB,
IV = I->second;
}

PN->addIncoming(IV, NewPred);
PN.addIncoming(IV, NewPred);
}
}

Expand Down
17 changes: 6 additions & 11 deletions llvm/lib/Transforms/Scalar/LoopDeletion.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -49,19 +49,18 @@ static bool isLoopDead(Loop *L, ScalarEvolution &SE,
// must pass through a PHI in the exit block, meaning that this check is
// sufficient to guarantee that no loop-variant values are used outside
// of the loop.
BasicBlock::iterator BI = ExitBlock->begin();
bool AllEntriesInvariant = true;
bool AllOutgoingValuesSame = true;
while (PHINode *P = dyn_cast<PHINode>(BI)) {
Value *incoming = P->getIncomingValueForBlock(ExitingBlocks[0]);
for (PHINode &P : ExitBlock->phis()) {
Value *incoming = P.getIncomingValueForBlock(ExitingBlocks[0]);

// Make sure all exiting blocks produce the same incoming value for the exit
// block. If there are different incoming values for different exiting
// blocks, then it is impossible to statically determine which value should
// be used.
AllOutgoingValuesSame =
all_of(makeArrayRef(ExitingBlocks).slice(1), [&](BasicBlock *BB) {
return incoming == P->getIncomingValueForBlock(BB);
return incoming == P.getIncomingValueForBlock(BB);
});

if (!AllOutgoingValuesSame)
Expand All @@ -72,8 +71,6 @@ static bool isLoopDead(Loop *L, ScalarEvolution &SE,
AllEntriesInvariant = false;
break;
}

++BI;
}

if (Changed)
Expand Down Expand Up @@ -162,11 +159,9 @@ static LoopDeletionResult deleteLoopIfDead(Loop *L, DominatorTree &DT,
if (ExitBlock && isLoopNeverExecuted(L)) {
DEBUG(dbgs() << "Loop is proven to never execute, delete it!");
// Set incoming value to undef for phi nodes in the exit block.
BasicBlock::iterator BI = ExitBlock->begin();
while (PHINode *P = dyn_cast<PHINode>(BI)) {
for (unsigned i = 0; i < P->getNumIncomingValues(); i++)
P->setIncomingValue(i, UndefValue::get(P->getType()));
BI++;
for (PHINode &P : ExitBlock->phis()) {
std::fill(P.incoming_values().begin(), P.incoming_values().end(),
UndefValue::get(P.getType()));
}
deleteDeadLoop(L, &DT, &SE, &LI);
++NumDeleted;
Expand Down
27 changes: 12 additions & 15 deletions llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -857,12 +857,11 @@ static MemAccessTy getAccessType(const TargetTransformInfo &TTI,

/// Return true if this AddRec is already a phi in its loop.
static bool isExistingPhi(const SCEVAddRecExpr *AR, ScalarEvolution &SE) {
for (BasicBlock::iterator I = AR->getLoop()->getHeader()->begin();
PHINode *PN = dyn_cast<PHINode>(I); ++I) {
if (SE.isSCEVable(PN->getType()) &&
(SE.getEffectiveSCEVType(PN->getType()) ==
for (PHINode &PN : AR->getLoop()->getHeader()->phis()) {
if (SE.isSCEVable(PN.getType()) &&
(SE.getEffectiveSCEVType(PN.getType()) ==
SE.getEffectiveSCEVType(AR->getType())) &&
SE.getSCEV(PN) == AR)
SE.getSCEV(&PN) == AR)
return true;
}
return false;
Expand Down Expand Up @@ -3013,15 +3012,14 @@ void LSRInstance::CollectChains() {
} // Continue walking down the instructions.
} // Continue walking down the domtree.
// Visit phi backedges to determine if the chain can generate the IV postinc.
for (BasicBlock::iterator I = L->getHeader()->begin();
PHINode *PN = dyn_cast<PHINode>(I); ++I) {
if (!SE.isSCEVable(PN->getType()))
for (PHINode &PN : L->getHeader()->phis()) {
if (!SE.isSCEVable(PN.getType()))
continue;

Instruction *IncV =
dyn_cast<Instruction>(PN->getIncomingValueForBlock(L->getLoopLatch()));
dyn_cast<Instruction>(PN.getIncomingValueForBlock(L->getLoopLatch()));
if (IncV)
ChainInstruction(PN, IncV, ChainUsersVec);
ChainInstruction(&PN, IncV, ChainUsersVec);
}
// Remove any unprofitable chains.
unsigned ChainIdx = 0;
Expand Down Expand Up @@ -3152,12 +3150,11 @@ void LSRInstance::GenerateIVChain(const IVChain &Chain, SCEVExpander &Rewriter,
// If LSR created a new, wider phi, we may also replace its postinc. We only
// do this if we also found a wide value for the head of the chain.
if (isa<PHINode>(Chain.tailUserInst())) {
for (BasicBlock::iterator I = L->getHeader()->begin();
PHINode *Phi = dyn_cast<PHINode>(I); ++I) {
if (!isCompatibleIVType(Phi, IVSrc))
for (PHINode &Phi : L->getHeader()->phis()) {
if (!isCompatibleIVType(&Phi, IVSrc))
continue;
Instruction *PostIncV = dyn_cast<Instruction>(
Phi->getIncomingValueForBlock(L->getLoopLatch()));
Phi.getIncomingValueForBlock(L->getLoopLatch()));
if (!PostIncV || (SE.getSCEV(PostIncV) != SE.getSCEV(IVSrc)))
continue;
Value *IVOper = IVSrc;
Expand All @@ -3168,7 +3165,7 @@ void LSRInstance::GenerateIVChain(const IVChain &Chain, SCEVExpander &Rewriter,
Builder.SetCurrentDebugLocation(PostIncV->getDebugLoc());
IVOper = Builder.CreatePointerCast(IVSrc, PostIncTy, "lsr.chain");
}
Phi->replaceUsesOfWith(PostIncV, IVOper);
Phi.replaceUsesOfWith(PostIncV, IVOper);
DeadInsts.emplace_back(PostIncV);
}
}
Expand Down
14 changes: 6 additions & 8 deletions llvm/lib/Transforms/Scalar/LoopUnswitch.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1274,12 +1274,11 @@ void LoopUnswitch::UnswitchNontrivialCondition(Value *LIC, Constant *Val,

// If the successor of the exit block had PHI nodes, add an entry for
// NewExit.
for (BasicBlock::iterator I = ExitSucc->begin();
PHINode *PN = dyn_cast<PHINode>(I); ++I) {
Value *V = PN->getIncomingValueForBlock(ExitBlocks[i]);
for (PHINode &PN : ExitSucc->phis()) {
Value *V = PN.getIncomingValueForBlock(ExitBlocks[i]);
ValueToValueMapTy::iterator It = VMap.find(V);
if (It != VMap.end()) V = It->second;
PN->addIncoming(V, NewExit);
PN.addIncoming(V, NewExit);
}

if (LandingPadInst *LPad = NewExit->getLandingPadInst()) {
Expand Down Expand Up @@ -1496,10 +1495,9 @@ void LoopUnswitch::RewriteLoopBodyWithConditionConstant(Loop *L, Value *LIC,
BranchInst::Create(Abort, OldSISucc,
ConstantInt::getTrue(Context), NewSISucc);
// Release the PHI operands for this edge.
for (BasicBlock::iterator II = NewSISucc->begin();
PHINode *PN = dyn_cast<PHINode>(II); ++II)
PN->setIncomingValue(PN->getBasicBlockIndex(Switch),
UndefValue::get(PN->getType()));
for (PHINode &PN : NewSISucc->phis())
PN.setIncomingValue(PN.getBasicBlockIndex(Switch),
UndefValue::get(PN.getType()));
// Tell the domtree about the new block. We don't fully update the
// domtree here -- instead we force it to do a full recomputation
// after the pass is complete -- but we do need to inform it of
Expand Down
6 changes: 2 additions & 4 deletions llvm/lib/Transforms/Scalar/SCCP.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -523,10 +523,8 @@ class SCCPSolver : public InstVisitor<SCCPSolver> {
DEBUG(dbgs() << "Marking Edge Executable: " << Source->getName()
<< " -> " << Dest->getName() << '\n');

PHINode *PN;
for (BasicBlock::iterator I = Dest->begin();
(PN = dyn_cast<PHINode>(I)); ++I)
visitPHINode(*PN);
for (PHINode &PN : Dest->phis())
visitPHINode(PN);
}
}

Expand Down
34 changes: 12 additions & 22 deletions llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -271,19 +271,14 @@ static bool areLoopExitPHIsLoopInvariant(Loop &L, BasicBlock &ExitingBB,
static void rewritePHINodesForUnswitchedExitBlock(BasicBlock &UnswitchedBB,
BasicBlock &OldExitingBB,
BasicBlock &OldPH) {
for (Instruction &I : UnswitchedBB) {
auto *PN = dyn_cast<PHINode>(&I);
if (!PN)
// No more PHIs to check.
break;

for (PHINode &PN : UnswitchedBB.phis()) {
// When the loop exit is directly unswitched we just need to update the
// incoming basic block. We loop to handle weird cases with repeated
// incoming blocks, but expect to typically only have one operand here.
for (auto i : seq<int>(0, PN->getNumOperands())) {
assert(PN->getIncomingBlock(i) == &OldExitingBB &&
for (auto i : seq<int>(0, PN.getNumOperands())) {
assert(PN.getIncomingBlock(i) == &OldExitingBB &&
"Found incoming block different from unique predecessor!");
PN->setIncomingBlock(i, &OldPH);
PN.setIncomingBlock(i, &OldPH);
}
}
}
Expand All @@ -302,14 +297,9 @@ static void rewritePHINodesForExitAndUnswitchedBlocks(BasicBlock &ExitBB,
assert(&ExitBB != &UnswitchedBB &&
"Must have different loop exit and unswitched blocks!");
Instruction *InsertPt = &*UnswitchedBB.begin();
for (Instruction &I : ExitBB) {
auto *PN = dyn_cast<PHINode>(&I);
if (!PN)
// No more PHIs to check.
break;

auto *NewPN = PHINode::Create(PN->getType(), /*NumReservedValues*/ 2,
PN->getName() + ".split", InsertPt);
for (PHINode &PN : ExitBB.phis()) {
auto *NewPN = PHINode::Create(PN.getType(), /*NumReservedValues*/ 2,
PN.getName() + ".split", InsertPt);

// Walk backwards over the old PHI node's inputs to minimize the cost of
// removing each one. We have to do this weird loop manually so that we
Expand All @@ -320,18 +310,18 @@ static void rewritePHINodesForExitAndUnswitchedBlocks(BasicBlock &ExitBB,
// allowed us to create a single entry for a predecessor block without
// having separate entries for each "edge" even though these edges are
// required to produce identical results.
for (int i = PN->getNumIncomingValues() - 1; i >= 0; --i) {
if (PN->getIncomingBlock(i) != &OldExitingBB)
for (int i = PN.getNumIncomingValues() - 1; i >= 0; --i) {
if (PN.getIncomingBlock(i) != &OldExitingBB)
continue;

Value *Incoming = PN->removeIncomingValue(i);
Value *Incoming = PN.removeIncomingValue(i);
NewPN->addIncoming(Incoming, &OldPH);
}

// Now replace the old PHI with the new one and wire the old one in as an
// input to the new one.
PN->replaceAllUsesWith(NewPN);
NewPN->addIncoming(PN, &ExitBB);
PN.replaceAllUsesWith(NewPN);
NewPN->addIncoming(&PN, &ExitBB);
}
}

Expand Down
26 changes: 9 additions & 17 deletions llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -94,9 +94,8 @@ bool llvm::DeleteDeadPHIs(BasicBlock *BB, const TargetLibraryInfo *TLI) {
// Recursively deleting a PHI may cause multiple PHIs to be deleted
// or RAUW'd undef, so use an array of WeakTrackingVH for the PHIs to delete.
SmallVector<WeakTrackingVH, 8> PHIs;
for (BasicBlock::iterator I = BB->begin();
PHINode *PN = dyn_cast<PHINode>(I); ++I)
PHIs.push_back(PN);
for (PHINode &PN : BB->phis())
PHIs.push_back(&PN);

bool Changed = false;
for (unsigned i = 0, e = PHIs.size(); i != e; ++i)
Expand Down Expand Up @@ -134,24 +133,17 @@ bool llvm::MergeBlockIntoPredecessor(BasicBlock *BB, DominatorTree *DT,
if (!OnlySucc) return false;

// Can't merge if there is PHI loop.
for (BasicBlock::iterator BI = BB->begin(), BE = BB->end(); BI != BE; ++BI) {
if (PHINode *PN = dyn_cast<PHINode>(BI)) {
for (Value *IncValue : PN->incoming_values())
if (IncValue == PN)
return false;
} else
break;
}
for (PHINode &PN : BB->phis())
for (Value *IncValue : PN.incoming_values())
if (IncValue == &PN)
return false;

// Begin by getting rid of unneeded PHIs.
SmallVector<Value *, 4> IncomingValues;
if (isa<PHINode>(BB->front())) {
for (auto &I : *BB)
if (PHINode *PN = dyn_cast<PHINode>(&I)) {
if (PN->getIncomingValue(0) != PN)
IncomingValues.push_back(PN->getIncomingValue(0));
} else
break;
for (PHINode &PN : BB->phis())
if (PN.getIncomingValue(0) != &PN)
IncomingValues.push_back(PN.getIncomingValue(0));
FoldSingleEntryPHINodes(BB, MemDep);
}

Expand Down
11 changes: 5 additions & 6 deletions llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -106,10 +106,9 @@ static void createPHIsForSplitLoopExit(ArrayRef<BasicBlock *> Preds,
SplitBB->isLandingPad()) && "SplitBB has non-PHI nodes!");

// For each PHI in the destination block.
for (BasicBlock::iterator I = DestBB->begin();
PHINode *PN = dyn_cast<PHINode>(I); ++I) {
unsigned Idx = PN->getBasicBlockIndex(SplitBB);
Value *V = PN->getIncomingValue(Idx);
for (PHINode &PN : DestBB->phis()) {
unsigned Idx = PN.getBasicBlockIndex(SplitBB);
Value *V = PN.getIncomingValue(Idx);

// If the input is a PHI which already satisfies LCSSA, don't create
// a new one.
Expand All @@ -119,13 +118,13 @@ static void createPHIsForSplitLoopExit(ArrayRef<BasicBlock *> Preds,

// Otherwise a new PHI is needed. Create one and populate it.
PHINode *NewPN = PHINode::Create(
PN->getType(), Preds.size(), "split",
PN.getType(), Preds.size(), "split",
SplitBB->isLandingPad() ? &SplitBB->front() : SplitBB->getTerminator());
for (unsigned i = 0, e = Preds.size(); i != e; ++i)
NewPN->addIncoming(V, Preds[i]);

// Update the original PHI.
PN->setIncomingValue(Idx, NewPN);
PN.setIncomingValue(Idx, NewPN);
}
}

Expand Down
22 changes: 8 additions & 14 deletions llvm/lib/Transforms/Utils/CallPromotionUtils.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -47,14 +47,11 @@ using namespace llvm;
///
static void fixupPHINodeForNormalDest(InvokeInst *Invoke, BasicBlock *OrigBlock,
BasicBlock *MergeBlock) {
for (auto &I : *Invoke->getNormalDest()) {
auto *Phi = dyn_cast<PHINode>(&I);
if (!Phi)
break;
int Idx = Phi->getBasicBlockIndex(OrigBlock);
for (PHINode &Phi : Invoke->getNormalDest()->phis()) {
int Idx = Phi.getBasicBlockIndex(OrigBlock);
if (Idx == -1)
continue;
Phi->setIncomingBlock(Idx, MergeBlock);
Phi.setIncomingBlock(Idx, MergeBlock);
}
}

Expand Down Expand Up @@ -82,16 +79,13 @@ static void fixupPHINodeForNormalDest(InvokeInst *Invoke, BasicBlock *OrigBlock,
static void fixupPHINodeForUnwindDest(InvokeInst *Invoke, BasicBlock *OrigBlock,
BasicBlock *ThenBlock,
BasicBlock *ElseBlock) {
for (auto &I : *Invoke->getUnwindDest()) {
auto *Phi = dyn_cast<PHINode>(&I);
if (!Phi)
break;
int Idx = Phi->getBasicBlockIndex(OrigBlock);
for (PHINode &Phi : Invoke->getUnwindDest()->phis()) {
int Idx = Phi.getBasicBlockIndex(OrigBlock);
if (Idx == -1)
continue;
auto *V = Phi->getIncomingValue(Idx);
Phi->setIncomingBlock(Idx, ThenBlock);
Phi->addIncoming(V, ElseBlock);
auto *V = Phi.getIncomingValue(Idx);
Phi.setIncomingBlock(Idx, ThenBlock);
Phi.addIncoming(V, ElseBlock);
}
}

Expand Down
12 changes: 4 additions & 8 deletions llvm/lib/Transforms/Utils/CloneFunction.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -493,17 +493,13 @@ void llvm::CloneAndPruneIntoFromInst(Function *NewFunc, const Function *OldFunc,

// Handle PHI nodes specially, as we have to remove references to dead
// blocks.
for (BasicBlock::const_iterator I = BI.begin(), E = BI.end(); I != E; ++I) {
for (const PHINode &PN : BI.phis()) {
// PHI nodes may have been remapped to non-PHI nodes by the caller or
// during the cloning process.
if (const PHINode *PN = dyn_cast<PHINode>(I)) {
if (isa<PHINode>(VMap[PN]))
PHIToResolve.push_back(PN);
else
break;
} else {
if (isa<PHINode>(VMap[&PN]))
PHIToResolve.push_back(&PN);
else
break;
}
}

// Finally, remap the terminator instructions, as those can't be remapped
Expand Down
20 changes: 7 additions & 13 deletions llvm/lib/Transforms/Utils/LoopUnroll.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -258,11 +258,8 @@ static bool isEpilogProfitable(Loop *L) {
BasicBlock *PreHeader = L->getLoopPreheader();
BasicBlock *Header = L->getHeader();
assert(PreHeader && Header);
for (Instruction &BBI : *Header) {
PHINode *PN = dyn_cast<PHINode>(&BBI);
if (!PN)
break;
if (isa<ConstantInt>(PN->getIncomingValueForBlock(PreHeader)))
for (const PHINode &PN : Header->phis()) {
if (isa<ConstantInt>(PN.getIncomingValueForBlock(PreHeader)))
return true;
}
return false;
Expand Down Expand Up @@ -611,13 +608,12 @@ LoopUnrollResult llvm::UnrollLoop(
for (BasicBlock *Succ : successors(*BB)) {
if (L->contains(Succ))
continue;
for (BasicBlock::iterator BBI = Succ->begin();
PHINode *phi = dyn_cast<PHINode>(BBI); ++BBI) {
Value *Incoming = phi->getIncomingValueForBlock(*BB);
for (PHINode &PHI : Succ->phis()) {
Value *Incoming = PHI.getIncomingValueForBlock(*BB);
ValueToValueMapTy::iterator It = LastValueMap.find(Incoming);
if (It != LastValueMap.end())
Incoming = It->second;
phi->addIncoming(Incoming, New);
PHI.addIncoming(Incoming, New);
}
}
// Keep track of new headers and latches as we create them, so that
Expand Down Expand Up @@ -721,10 +717,8 @@ LoopUnrollResult llvm::UnrollLoop(
for (BasicBlock *Succ: successors(BB)) {
if (Succ == Headers[i])
continue;
for (BasicBlock::iterator BBI = Succ->begin();
PHINode *Phi = dyn_cast<PHINode>(BBI); ++BBI) {
Phi->removeIncomingValue(BB, false);
}
for (PHINode &Phi : Succ->phis())
Phi.removeIncomingValue(BB, false);
}
}
// Replace the conditional branch with an unconditional one.
Expand Down
50 changes: 19 additions & 31 deletions llvm/lib/Transforms/Utils/LoopUnrollRuntime.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -80,25 +80,21 @@ static void ConnectProlog(Loop *L, Value *BECount, unsigned Count,
// The new PHI node value is added as an operand of a PHI node in either
// the loop header or the loop exit block.
for (BasicBlock *Succ : successors(Latch)) {
for (Instruction &BBI : *Succ) {
PHINode *PN = dyn_cast<PHINode>(&BBI);
// Exit when we passed all PHI nodes.
if (!PN)
break;
for (PHINode &PN : Succ->phis()) {
// Add a new PHI node to the prolog end block and add the
// appropriate incoming values.
PHINode *NewPN = PHINode::Create(PN->getType(), 2, PN->getName() + ".unr",
PHINode *NewPN = PHINode::Create(PN.getType(), 2, PN.getName() + ".unr",
PrologExit->getFirstNonPHI());
// Adding a value to the new PHI node from the original loop preheader.
// This is the value that skips all the prolog code.
if (L->contains(PN)) {
NewPN->addIncoming(PN->getIncomingValueForBlock(NewPreHeader),
if (L->contains(&PN)) {
NewPN->addIncoming(PN.getIncomingValueForBlock(NewPreHeader),
PreHeader);
} else {
NewPN->addIncoming(UndefValue::get(PN->getType()), PreHeader);
NewPN->addIncoming(UndefValue::get(PN.getType()), PreHeader);
}

Value *V = PN->getIncomingValueForBlock(Latch);
Value *V = PN.getIncomingValueForBlock(Latch);
if (Instruction *I = dyn_cast<Instruction>(V)) {
if (L->contains(I)) {
V = VMap.lookup(I);
Expand All @@ -111,10 +107,10 @@ static void ConnectProlog(Loop *L, Value *BECount, unsigned Count,
// Update the existing PHI node operand with the value from the
// new PHI node. How this is done depends on if the existing
// PHI node is in the original loop block, or the exit block.
if (L->contains(PN)) {
PN->setIncomingValue(PN->getBasicBlockIndex(NewPreHeader), NewPN);
if (L->contains(&PN)) {
PN.setIncomingValue(PN.getBasicBlockIndex(NewPreHeader), NewPN);
} else {
PN->addIncoming(NewPN, PrologExit);
PN.addIncoming(NewPN, PrologExit);
}
}
}
Expand Down Expand Up @@ -191,11 +187,7 @@ static void ConnectEpilog(Loop *L, Value *ModVal, BasicBlock *NewExit,
// Exit (EpilogPN)

// Update PHI nodes at NewExit and Exit.
for (Instruction &BBI : *NewExit) {
PHINode *PN = dyn_cast<PHINode>(&BBI);
// Exit when we passed all PHI nodes.
if (!PN)
break;
for (PHINode &PN : NewExit->phis()) {
// PN should be used in another PHI located in Exit block as
// Exit was split by SplitBlockPredecessors into Exit and NewExit
// Basicaly it should look like:
Expand All @@ -207,14 +199,14 @@ static void ConnectEpilog(Loop *L, Value *ModVal, BasicBlock *NewExit,
//
// There is EpilogPreHeader incoming block instead of NewExit as
// NewExit was spilt 1 more time to get EpilogPreHeader.
assert(PN->hasOneUse() && "The phi should have 1 use");
PHINode *EpilogPN = cast<PHINode> (PN->use_begin()->getUser());
assert(PN.hasOneUse() && "The phi should have 1 use");
PHINode *EpilogPN = cast<PHINode>(PN.use_begin()->getUser());
assert(EpilogPN->getParent() == Exit && "EpilogPN should be in Exit block");

// Add incoming PreHeader from branch around the Loop
PN->addIncoming(UndefValue::get(PN->getType()), PreHeader);
PN.addIncoming(UndefValue::get(PN.getType()), PreHeader);

Value *V = PN->getIncomingValueForBlock(Latch);
Value *V = PN.getIncomingValueForBlock(Latch);
Instruction *I = dyn_cast<Instruction>(V);
if (I && L->contains(I))
// If value comes from an instruction in the loop add VMap value.
Expand Down Expand Up @@ -242,23 +234,19 @@ static void ConnectEpilog(Loop *L, Value *ModVal, BasicBlock *NewExit,
// Skip this as we already updated phis in exit blocks.
if (!L->contains(Succ))
continue;
for (Instruction &BBI : *Succ) {
PHINode *PN = dyn_cast<PHINode>(&BBI);
// Exit when we passed all PHI nodes.
if (!PN)
break;
for (PHINode &PN : Succ->phis()) {
// Add new PHI nodes to the loop exit block and update epilog
// PHIs with the new PHI values.
PHINode *NewPN = PHINode::Create(PN->getType(), 2, PN->getName() + ".unr",
PHINode *NewPN = PHINode::Create(PN.getType(), 2, PN.getName() + ".unr",
NewExit->getFirstNonPHI());
// Adding a value to the new PHI node from the unrolling loop preheader.
NewPN->addIncoming(PN->getIncomingValueForBlock(NewPreHeader), PreHeader);
NewPN->addIncoming(PN.getIncomingValueForBlock(NewPreHeader), PreHeader);
// Adding a value to the new PHI node from the unrolling loop latch.
NewPN->addIncoming(PN->getIncomingValueForBlock(Latch), Latch);
NewPN->addIncoming(PN.getIncomingValueForBlock(Latch), Latch);

// Update the existing PHI node operand with the value from the new PHI
// node. Corresponding instruction in epilog loop should be PHI.
PHINode *VPN = cast<PHINode>(VMap[&BBI]);
PHINode *VPN = cast<PHINode>(VMap[&PN]);
VPN->setIncomingValue(VPN->getBasicBlockIndex(EpilogPreHeader), NewPN);
}
}
Expand Down
14 changes: 6 additions & 8 deletions llvm/lib/Transforms/Utils/LoopUtils.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1321,27 +1321,25 @@ void llvm::deleteDeadLoop(Loop *L, DominatorTree *DT = nullptr,

// Rewrite phis in the exit block to get their inputs from the Preheader
// instead of the exiting block.
BasicBlock::iterator BI = ExitBlock->begin();
while (PHINode *P = dyn_cast<PHINode>(BI)) {
for (PHINode &P : ExitBlock->phis()) {
// Set the zero'th element of Phi to be from the preheader and remove all
// other incoming values. Given the loop has dedicated exits, all other
// incoming values must be from the exiting blocks.
int PredIndex = 0;
P->setIncomingBlock(PredIndex, Preheader);
P.setIncomingBlock(PredIndex, Preheader);
// Removes all incoming values from all other exiting blocks (including
// duplicate values from an exiting block).
// Nuke all entries except the zero'th entry which is the preheader entry.
// NOTE! We need to remove Incoming Values in the reverse order as done
// below, to keep the indices valid for deletion (removeIncomingValues
// updates getNumIncomingValues and shifts all values down into the operand
// being deleted).
for (unsigned i = 0, e = P->getNumIncomingValues() - 1; i != e; ++i)
P->removeIncomingValue(e - i, false);
for (unsigned i = 0, e = P.getNumIncomingValues() - 1; i != e; ++i)
P.removeIncomingValue(e - i, false);

assert((P->getNumIncomingValues() == 1 &&
P->getIncomingBlock(PredIndex) == Preheader) &&
assert((P.getNumIncomingValues() == 1 &&
P.getIncomingBlock(PredIndex) == Preheader) &&
"Should have exactly one value and that's from the preheader!");
++BI;
}

// Disconnect the loop body by branching directly to its exit.
Expand Down
8 changes: 3 additions & 5 deletions llvm/lib/Transforms/Utils/SSAUpdater.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -147,11 +147,9 @@ Value *SSAUpdater::GetValueInMiddleOfBlock(BasicBlock *BB) {
if (isa<PHINode>(BB->begin())) {
SmallDenseMap<BasicBlock *, Value *, 8> ValueMapping(PredValues.begin(),
PredValues.end());
PHINode *SomePHI;
for (BasicBlock::iterator It = BB->begin();
(SomePHI = dyn_cast<PHINode>(It)); ++It) {
if (IsEquivalentPHI(SomePHI, ValueMapping))
return SomePHI;
for (PHINode &SomePHI : BB->phis()) {
if (IsEquivalentPHI(&SomePHI, ValueMapping))
return &SomePHI;
}
}

Expand Down
122 changes: 51 additions & 71 deletions llvm/lib/Transforms/Utils/SimplifyCFG.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -283,12 +283,8 @@ isProfitableToFoldUnconditional(BranchInst *SI1, BranchInst *SI2,
/// of Succ.
static void AddPredecessorToBlock(BasicBlock *Succ, BasicBlock *NewPred,
BasicBlock *ExistPred) {
if (!isa<PHINode>(Succ->begin()))
return; // Quick exit if nothing to do

PHINode *PN;
for (BasicBlock::iterator I = Succ->begin(); (PN = dyn_cast<PHINode>(I)); ++I)
PN->addIncoming(PN->getIncomingValueForBlock(ExistPred), NewPred);
for (PHINode &PN : Succ->phis())
PN.addIncoming(PN.getIncomingValueForBlock(ExistPred), NewPred);
}

/// Compute an abstract "cost" of speculating the given instruction,
Expand Down Expand Up @@ -1228,11 +1224,9 @@ bool SimplifyCFGOpt::FoldValueComparisonIntoPredecessors(TerminatorInst *TI,
static bool isSafeToHoistInvoke(BasicBlock *BB1, BasicBlock *BB2,
Instruction *I1, Instruction *I2) {
for (BasicBlock *Succ : successors(BB1)) {
PHINode *PN;
for (BasicBlock::iterator BBI = Succ->begin();
(PN = dyn_cast<PHINode>(BBI)); ++BBI) {
Value *BB1V = PN->getIncomingValueForBlock(BB1);
Value *BB2V = PN->getIncomingValueForBlock(BB2);
for (const PHINode &PN : Succ->phis()) {
Value *BB1V = PN.getIncomingValueForBlock(BB1);
Value *BB2V = PN.getIncomingValueForBlock(BB2);
if (BB1V != BB2V && (BB1V == I1 || BB2V == I2)) {
return false;
}
Expand Down Expand Up @@ -1332,18 +1326,16 @@ static bool HoistThenElseCodeToIf(BranchInst *BI,
return Changed;

for (BasicBlock *Succ : successors(BB1)) {
PHINode *PN;
for (BasicBlock::iterator BBI = Succ->begin();
(PN = dyn_cast<PHINode>(BBI)); ++BBI) {
Value *BB1V = PN->getIncomingValueForBlock(BB1);
Value *BB2V = PN->getIncomingValueForBlock(BB2);
for (PHINode &PN : Succ->phis()) {
Value *BB1V = PN.getIncomingValueForBlock(BB1);
Value *BB2V = PN.getIncomingValueForBlock(BB2);
if (BB1V == BB2V)
continue;

// Check for passingValueIsAlwaysUndefined here because we would rather
// eliminate undefined control flow then converting it to a select.
if (passingValueIsAlwaysUndefined(BB1V, PN) ||
passingValueIsAlwaysUndefined(BB2V, PN))
if (passingValueIsAlwaysUndefined(BB1V, &PN) ||
passingValueIsAlwaysUndefined(BB2V, &PN))
return Changed;

if (isa<ConstantExpr>(BB1V) && !isSafeToSpeculativelyExecute(BB1V))
Expand All @@ -1369,11 +1361,9 @@ static bool HoistThenElseCodeToIf(BranchInst *BI,
// nodes, so we insert select instruction to compute the final result.
std::map<std::pair<Value *, Value *>, SelectInst *> InsertedSelects;
for (BasicBlock *Succ : successors(BB1)) {
PHINode *PN;
for (BasicBlock::iterator BBI = Succ->begin();
(PN = dyn_cast<PHINode>(BBI)); ++BBI) {
Value *BB1V = PN->getIncomingValueForBlock(BB1);
Value *BB2V = PN->getIncomingValueForBlock(BB2);
for (PHINode &PN : Succ->phis()) {
Value *BB1V = PN.getIncomingValueForBlock(BB1);
Value *BB2V = PN.getIncomingValueForBlock(BB2);
if (BB1V == BB2V)
continue;

Expand All @@ -1386,9 +1376,9 @@ static bool HoistThenElseCodeToIf(BranchInst *BI,
BB1V->getName() + "." + BB2V->getName(), BI));

// Make the PHI node use the select for all incoming values for BB1/BB2
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
if (PN->getIncomingBlock(i) == BB1 || PN->getIncomingBlock(i) == BB2)
PN->setIncomingValue(i, SI);
for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i)
if (PN.getIncomingBlock(i) == BB1 || PN.getIncomingBlock(i) == BB2)
PN.setIncomingValue(i, SI);
}
}

Expand Down Expand Up @@ -1999,19 +1989,18 @@ static bool SpeculativelyExecuteBB(BranchInst *BI, BasicBlock *ThenBB,

// Check that the PHI nodes can be converted to selects.
bool HaveRewritablePHIs = false;
for (BasicBlock::iterator I = EndBB->begin();
PHINode *PN = dyn_cast<PHINode>(I); ++I) {
Value *OrigV = PN->getIncomingValueForBlock(BB);
Value *ThenV = PN->getIncomingValueForBlock(ThenBB);
for (PHINode &PN : EndBB->phis()) {
Value *OrigV = PN.getIncomingValueForBlock(BB);
Value *ThenV = PN.getIncomingValueForBlock(ThenBB);

// FIXME: Try to remove some of the duplication with HoistThenElseCodeToIf.
// Skip PHIs which are trivial.
if (ThenV == OrigV)
continue;

// Don't convert to selects if we could remove undefined behavior instead.
if (passingValueIsAlwaysUndefined(OrigV, PN) ||
passingValueIsAlwaysUndefined(ThenV, PN))
if (passingValueIsAlwaysUndefined(OrigV, &PN) ||
passingValueIsAlwaysUndefined(ThenV, &PN))
return false;

HaveRewritablePHIs = true;
Expand Down Expand Up @@ -2072,12 +2061,11 @@ static bool SpeculativelyExecuteBB(BranchInst *BI, BasicBlock *ThenBB,

// Insert selects and rewrite the PHI operands.
IRBuilder<NoFolder> Builder(BI);
for (BasicBlock::iterator I = EndBB->begin();
PHINode *PN = dyn_cast<PHINode>(I); ++I) {
unsigned OrigI = PN->getBasicBlockIndex(BB);
unsigned ThenI = PN->getBasicBlockIndex(ThenBB);
Value *OrigV = PN->getIncomingValue(OrigI);
Value *ThenV = PN->getIncomingValue(ThenI);
for (PHINode &PN : EndBB->phis()) {
unsigned OrigI = PN.getBasicBlockIndex(BB);
unsigned ThenI = PN.getBasicBlockIndex(ThenBB);
Value *OrigV = PN.getIncomingValue(OrigI);
Value *ThenV = PN.getIncomingValue(ThenI);

// Skip PHIs which are trivial.
if (OrigV == ThenV)
Expand All @@ -2091,8 +2079,8 @@ static bool SpeculativelyExecuteBB(BranchInst *BI, BasicBlock *ThenBB,
std::swap(TrueV, FalseV);
Value *V = Builder.CreateSelect(
BrCond, TrueV, FalseV, "spec.select", BI);
PN->setIncomingValue(OrigI, V);
PN->setIncomingValue(ThenI, V);
PN.setIncomingValue(OrigI, V);
PN.setIncomingValue(ThenI, V);
}

// Remove speculated dbg intrinsics.
Expand Down Expand Up @@ -3335,17 +3323,15 @@ static bool SimplifyCondBranchToCondBranch(BranchInst *PBI, BranchInst *BI,
// it. If it has PHIs though, the PHIs may have different
// entries for BB and PBI's BB. If so, insert a select to make
// them agree.
PHINode *PN;
for (BasicBlock::iterator II = CommonDest->begin();
(PN = dyn_cast<PHINode>(II)); ++II) {
Value *BIV = PN->getIncomingValueForBlock(BB);
unsigned PBBIdx = PN->getBasicBlockIndex(PBI->getParent());
Value *PBIV = PN->getIncomingValue(PBBIdx);
for (PHINode &PN : CommonDest->phis()) {
Value *BIV = PN.getIncomingValueForBlock(BB);
unsigned PBBIdx = PN.getBasicBlockIndex(PBI->getParent());
Value *PBIV = PN.getIncomingValue(PBBIdx);
if (BIV != PBIV) {
// Insert a select in PBI to pick the right value.
SelectInst *NV = cast<SelectInst>(
Builder.CreateSelect(PBICond, PBIV, BIV, PBIV->getName() + ".mux"));
PN->setIncomingValue(PBBIdx, NV);
PN.setIncomingValue(PBBIdx, NV);
// Although the select has the same condition as PBI, the original branch
// weights for PBI do not apply to the new select because the select's
// 'logical' edges are incoming edges of the phi that is eliminated, not
Expand Down Expand Up @@ -4451,17 +4437,16 @@ static PHINode *FindPHIForConditionForwarding(ConstantInt *CaseValue,

BasicBlock *Succ = Branch->getSuccessor(0);

BasicBlock::iterator I = Succ->begin();
while (PHINode *PHI = dyn_cast<PHINode>(I++)) {
int Idx = PHI->getBasicBlockIndex(BB);
for (PHINode &PHI : Succ->phis()) {
int Idx = PHI.getBasicBlockIndex(BB);
assert(Idx >= 0 && "PHI has no entry for predecessor?");

Value *InValue = PHI->getIncomingValue(Idx);
Value *InValue = PHI.getIncomingValue(Idx);
if (InValue != CaseValue)
continue;

*PhiIndex = Idx;
return PHI;
return &PHI;
}

return nullptr;
Expand Down Expand Up @@ -4491,19 +4476,16 @@ static bool ForwardSwitchConditionToPHI(SwitchInst *SI) {
// -->
// %r = phi i32 ... [ %x, %switchbb ] ...

for (Instruction &InstInCaseDest : *CaseDest) {
auto *Phi = dyn_cast<PHINode>(&InstInCaseDest);
if (!Phi) break;

for (PHINode &Phi : CaseDest->phis()) {
// This only works if there is exactly 1 incoming edge from the switch to
// a phi. If there is >1, that means multiple cases of the switch map to 1
// value in the phi, and that phi value is not the switch condition. Thus,
// this transform would not make sense (the phi would be invalid because
// a phi can't have different incoming values from the same block).
int SwitchBBIdx = Phi->getBasicBlockIndex(SwitchBlock);
if (Phi->getIncomingValue(SwitchBBIdx) == CaseValue &&
count(Phi->blocks(), SwitchBlock) == 1) {
Phi->setIncomingValue(SwitchBBIdx, SI->getCondition());
int SwitchBBIdx = Phi.getBasicBlockIndex(SwitchBlock);
if (Phi.getIncomingValue(SwitchBBIdx) == CaseValue &&
count(Phi.blocks(), SwitchBlock) == 1) {
Phi.setIncomingValue(SwitchBBIdx, SI->getCondition());
Changed = true;
}
}
Expand Down Expand Up @@ -4656,22 +4638,21 @@ GetCaseResults(SwitchInst *SI, ConstantInt *CaseVal, BasicBlock *CaseDest,
return false;

// Get the values for this case from phi nodes in the destination block.
BasicBlock::iterator I = (*CommonDest)->begin();
while (PHINode *PHI = dyn_cast<PHINode>(I++)) {
int Idx = PHI->getBasicBlockIndex(Pred);
for (PHINode &PHI : (*CommonDest)->phis()) {
int Idx = PHI.getBasicBlockIndex(Pred);
if (Idx == -1)
continue;

Constant *ConstVal =
LookupConstant(PHI->getIncomingValue(Idx), ConstantPool);
LookupConstant(PHI.getIncomingValue(Idx), ConstantPool);
if (!ConstVal)
return false;

// Be conservative about which kinds of constants we support.
if (!ValidLookupTableConstant(ConstVal, TTI))
return false;

Res.push_back(std::make_pair(PHI, ConstVal));
Res.push_back(std::make_pair(&PHI, ConstVal));
}

return Res.size() > 0;
Expand Down Expand Up @@ -5946,14 +5927,13 @@ static bool passingValueIsAlwaysUndefined(Value *V, Instruction *I) {
/// If BB has an incoming value that will always trigger undefined behavior
/// (eg. null pointer dereference), remove the branch leading here.
static bool removeUndefIntroducingPredecessor(BasicBlock *BB) {
for (BasicBlock::iterator i = BB->begin();
PHINode *PHI = dyn_cast<PHINode>(i); ++i)
for (unsigned i = 0, e = PHI->getNumIncomingValues(); i != e; ++i)
if (passingValueIsAlwaysUndefined(PHI->getIncomingValue(i), PHI)) {
TerminatorInst *T = PHI->getIncomingBlock(i)->getTerminator();
for (PHINode &PHI : BB->phis())
for (unsigned i = 0, e = PHI.getNumIncomingValues(); i != e; ++i)
if (passingValueIsAlwaysUndefined(PHI.getIncomingValue(i), &PHI)) {
TerminatorInst *T = PHI.getIncomingBlock(i)->getTerminator();
IRBuilder<> Builder(T);
if (BranchInst *BI = dyn_cast<BranchInst>(T)) {
BB->removePredecessor(PHI->getIncomingBlock(i));
BB->removePredecessor(PHI.getIncomingBlock(i));
// Turn uncoditional branches into unreachables and remove the dead
// destination from conditional branches.
if (BI->isUnconditional())
Expand Down
54 changes: 18 additions & 36 deletions llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -4164,15 +4164,12 @@ void InnerLoopVectorizer::fixCrossIterationPHIs() {
// the currently empty PHI nodes. At this point every instruction in the
// original loop is widened to a vector form so we can use them to construct
// the incoming edges.
for (Instruction &I : *OrigLoop->getHeader()) {
PHINode *Phi = dyn_cast<PHINode>(&I);
if (!Phi)
break;
for (PHINode &Phi : OrigLoop->getHeader()->phis()) {
// Handle first-order recurrences and reductions that need to be fixed.
if (Legal->isFirstOrderRecurrence(Phi))
fixFirstOrderRecurrence(Phi);
else if (Legal->isReductionVariable(Phi))
fixReduction(Phi);
if (Legal->isFirstOrderRecurrence(&Phi))
fixFirstOrderRecurrence(&Phi);
else if (Legal->isReductionVariable(&Phi))
fixReduction(&Phi);
}
}

Expand Down Expand Up @@ -4337,12 +4334,9 @@ void InnerLoopVectorizer::fixFirstOrderRecurrence(PHINode *Phi) {
// vector recurrence we extracted in the middle block. Since the loop is in
// LCSSA form, we just need to find the phi node for the original scalar
// recurrence in the exit block, and then add an edge for the middle block.
for (auto &I : *LoopExitBlock) {
auto *LCSSAPhi = dyn_cast<PHINode>(&I);
if (!LCSSAPhi)
break;
if (LCSSAPhi->getIncomingValue(0) == Phi) {
LCSSAPhi->addIncoming(ExtractForPhiUsedOutsideLoop, LoopMiddleBlock);
for (PHINode &LCSSAPhi : LoopExitBlock->phis()) {
if (LCSSAPhi.getIncomingValue(0) == Phi) {
LCSSAPhi.addIncoming(ExtractForPhiUsedOutsideLoop, LoopMiddleBlock);
break;
}
}
Expand Down Expand Up @@ -4499,21 +4493,15 @@ void InnerLoopVectorizer::fixReduction(PHINode *Phi) {
// inside and outside of the scalar remainder loop.
// We know that the loop is in LCSSA form. We need to update the
// PHI nodes in the exit blocks.
for (BasicBlock::iterator LEI = LoopExitBlock->begin(),
LEE = LoopExitBlock->end();
LEI != LEE; ++LEI) {
PHINode *LCSSAPhi = dyn_cast<PHINode>(LEI);
if (!LCSSAPhi)
break;

for (PHINode &LCSSAPhi : LoopExitBlock->phis()) {
// All PHINodes need to have a single entry edge, or two if
// we already fixed them.
assert(LCSSAPhi->getNumIncomingValues() < 3 && "Invalid LCSSA PHI");
assert(LCSSAPhi.getNumIncomingValues() < 3 && "Invalid LCSSA PHI");

// We found a reduction value exit-PHI. Update it with the
// incoming bypass edge.
if (LCSSAPhi->getIncomingValue(0) == LoopExitInst)
LCSSAPhi->addIncoming(ReducedPartRdx, LoopMiddleBlock);
if (LCSSAPhi.getIncomingValue(0) == LoopExitInst)
LCSSAPhi.addIncoming(ReducedPartRdx, LoopMiddleBlock);
} // end of the LCSSA phi scan.

// Fix the scalar loop reduction variable with the incoming reduction sum
Expand All @@ -4528,14 +4516,11 @@ void InnerLoopVectorizer::fixReduction(PHINode *Phi) {
}

void InnerLoopVectorizer::fixLCSSAPHIs() {
for (Instruction &LEI : *LoopExitBlock) {
auto *LCSSAPhi = dyn_cast<PHINode>(&LEI);
if (!LCSSAPhi)
break;
if (LCSSAPhi->getNumIncomingValues() == 1) {
assert(OrigLoop->isLoopInvariant(LCSSAPhi->getIncomingValue(0)) &&
for (PHINode &LCSSAPhi : LoopExitBlock->phis()) {
if (LCSSAPhi.getNumIncomingValues() == 1) {
assert(OrigLoop->isLoopInvariant(LCSSAPhi.getIncomingValue(0)) &&
"Incoming value isn't loop invariant");
LCSSAPhi->addIncoming(LCSSAPhi->getIncomingValue(0), LoopMiddleBlock);
LCSSAPhi.addIncoming(LCSSAPhi.getIncomingValue(0), LoopMiddleBlock);
}
}
}
Expand Down Expand Up @@ -4981,11 +4966,8 @@ void InnerLoopVectorizer::updateAnalysis() {
/// Phi nodes with constant expressions that can trap are not safe to if
/// convert.
static bool canIfConvertPHINodes(BasicBlock *BB) {
for (Instruction &I : *BB) {
auto *Phi = dyn_cast<PHINode>(&I);
if (!Phi)
return true;
for (Value *V : Phi->incoming_values())
for (PHINode &Phi : BB->phis()) {
for (Value *V : Phi.incoming_values())
if (auto *C = dyn_cast<Constant>(V))
if (C->canTrap())
return false;
Expand Down