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-rw-r--r--lib/Transforms/Scalar/JumpThreading.cpp39
1 files changed, 20 insertions, 19 deletions
diff --git a/lib/Transforms/Scalar/JumpThreading.cpp b/lib/Transforms/Scalar/JumpThreading.cpp
index 067deb7..230a381 100644
--- a/lib/Transforms/Scalar/JumpThreading.cpp
+++ b/lib/Transforms/Scalar/JumpThreading.cpp
@@ -11,7 +11,6 @@
//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "jump-threading"
#include "llvm/Transforms/Scalar.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/DenseSet.h"
@@ -38,6 +37,8 @@
#include "llvm/Transforms/Utils/SSAUpdater.h"
using namespace llvm;
+#define DEBUG_TYPE "jump-threading"
+
STATISTIC(NumThreads, "Number of jumps threaded");
STATISTIC(NumFolds, "Number of terminators folded");
STATISTIC(NumDupes, "Number of branch blocks duplicated to eliminate phi");
@@ -153,7 +154,7 @@ bool JumpThreading::runOnFunction(Function &F) {
DEBUG(dbgs() << "Jump threading on function '" << F.getName() << "'\n");
DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>();
- DL = DLP ? &DLP->getDataLayout() : 0;
+ DL = DLP ? &DLP->getDataLayout() : nullptr;
TLI = &getAnalysis<TargetLibraryInfo>();
LVI = &getAnalysis<LazyValueInfo>();
@@ -308,7 +309,7 @@ void JumpThreading::FindLoopHeaders(Function &F) {
/// Returns null if Val is null or not an appropriate constant.
static Constant *getKnownConstant(Value *Val, ConstantPreference Preference) {
if (!Val)
- return 0;
+ return nullptr;
// Undef is "known" enough.
if (UndefValue *U = dyn_cast<UndefValue>(Val))
@@ -352,7 +353,7 @@ ComputeValueKnownInPredecessors(Value *V, BasicBlock *BB, PredValueInfo &Result,
// If V is a non-instruction value, or an instruction in a different block,
// then it can't be derived from a PHI.
Instruction *I = dyn_cast<Instruction>(V);
- if (I == 0 || I->getParent() != BB) {
+ if (!I || I->getParent() != BB) {
// Okay, if this is a live-in value, see if it has a known value at the end
// of any of our predecessors.
@@ -495,7 +496,7 @@ ComputeValueKnownInPredecessors(Value *V, BasicBlock *BB, PredValueInfo &Result,
Value *RHS = Cmp->getOperand(1)->DoPHITranslation(BB, PredBB);
Value *Res = SimplifyCmpInst(Cmp->getPredicate(), LHS, RHS, DL);
- if (Res == 0) {
+ if (!Res) {
if (!isa<Constant>(RHS))
continue;
@@ -581,7 +582,7 @@ ComputeValueKnownInPredecessors(Value *V, BasicBlock *BB, PredValueInfo &Result,
// Either operand will do, so be sure to pick the one that's a known
// constant.
// FIXME: Do this more cleverly if both values are known constants?
- KnownCond = (TrueVal != 0);
+ KnownCond = (TrueVal != nullptr);
}
// See if the select has a known constant value for this predecessor.
@@ -737,7 +738,7 @@ bool JumpThreading::ProcessBlock(BasicBlock *BB) {
Instruction *CondInst = dyn_cast<Instruction>(Condition);
// All the rest of our checks depend on the condition being an instruction.
- if (CondInst == 0) {
+ if (!CondInst) {
// FIXME: Unify this with code below.
if (ProcessThreadableEdges(Condition, BB, Preference))
return true;
@@ -890,7 +891,7 @@ bool JumpThreading::SimplifyPartiallyRedundantLoad(LoadInst *LI) {
SmallPtrSet<BasicBlock*, 8> PredsScanned;
typedef SmallVector<std::pair<BasicBlock*, Value*>, 8> AvailablePredsTy;
AvailablePredsTy AvailablePreds;
- BasicBlock *OneUnavailablePred = 0;
+ BasicBlock *OneUnavailablePred = nullptr;
// If we got here, the loaded value is transparent through to the start of the
// block. Check to see if it is available in any of the predecessor blocks.
@@ -904,16 +905,16 @@ bool JumpThreading::SimplifyPartiallyRedundantLoad(LoadInst *LI) {
// Scan the predecessor to see if the value is available in the pred.
BBIt = PredBB->end();
- MDNode *ThisTBAATag = 0;
+ MDNode *ThisTBAATag = nullptr;
Value *PredAvailable = FindAvailableLoadedValue(LoadedPtr, PredBB, BBIt, 6,
- 0, &ThisTBAATag);
+ nullptr, &ThisTBAATag);
if (!PredAvailable) {
OneUnavailablePred = PredBB;
continue;
}
// If tbaa tags disagree or are not present, forget about them.
- if (TBAATag != ThisTBAATag) TBAATag = 0;
+ if (TBAATag != ThisTBAATag) TBAATag = nullptr;
// If so, this load is partially redundant. Remember this info so that we
// can create a PHI node.
@@ -929,7 +930,7 @@ bool JumpThreading::SimplifyPartiallyRedundantLoad(LoadInst *LI) {
// predecessor, we want to insert a merge block for those common predecessors.
// This ensures that we only have to insert one reload, thus not increasing
// code size.
- BasicBlock *UnavailablePred = 0;
+ BasicBlock *UnavailablePred = nullptr;
// If there is exactly one predecessor where the value is unavailable, the
// already computed 'OneUnavailablePred' block is it. If it ends in an
@@ -996,7 +997,7 @@ bool JumpThreading::SimplifyPartiallyRedundantLoad(LoadInst *LI) {
BasicBlock *P = *PI;
AvailablePredsTy::iterator I =
std::lower_bound(AvailablePreds.begin(), AvailablePreds.end(),
- std::make_pair(P, (Value*)0));
+ std::make_pair(P, (Value*)nullptr));
assert(I != AvailablePreds.end() && I->first == P &&
"Didn't find entry for predecessor!");
@@ -1103,7 +1104,7 @@ bool JumpThreading::ProcessThreadableEdges(Value *Cond, BasicBlock *BB,
SmallPtrSet<BasicBlock*, 16> SeenPreds;
SmallVector<std::pair<BasicBlock*, BasicBlock*>, 16> PredToDestList;
- BasicBlock *OnlyDest = 0;
+ BasicBlock *OnlyDest = nullptr;
BasicBlock *MultipleDestSentinel = (BasicBlock*)(intptr_t)~0ULL;
for (unsigned i = 0, e = PredValues.size(); i != e; ++i) {
@@ -1120,7 +1121,7 @@ bool JumpThreading::ProcessThreadableEdges(Value *Cond, BasicBlock *BB,
BasicBlock *DestBB;
if (isa<UndefValue>(Val))
- DestBB = 0;
+ DestBB = nullptr;
else if (BranchInst *BI = dyn_cast<BranchInst>(BB->getTerminator()))
DestBB = BI->getSuccessor(cast<ConstantInt>(Val)->isZero());
else if (SwitchInst *SI = dyn_cast<SwitchInst>(BB->getTerminator())) {
@@ -1171,7 +1172,7 @@ bool JumpThreading::ProcessThreadableEdges(Value *Cond, BasicBlock *BB,
// If the threadable edges are branching on an undefined value, we get to pick
// the destination that these predecessors should get to.
- if (MostPopularDest == 0)
+ if (!MostPopularDest)
MostPopularDest = BB->getTerminator()->
getSuccessor(GetBestDestForJumpOnUndef(BB));
@@ -1273,7 +1274,7 @@ bool JumpThreading::ProcessBranchOnXOR(BinaryOperator *BO) {
}
// Determine which value to split on, true, false, or undef if neither.
- ConstantInt *SplitVal = 0;
+ ConstantInt *SplitVal = nullptr;
if (NumTrue > NumFalse)
SplitVal = ConstantInt::getTrue(BB->getContext());
else if (NumTrue != 0 || NumFalse != 0)
@@ -1294,7 +1295,7 @@ bool JumpThreading::ProcessBranchOnXOR(BinaryOperator *BO) {
// help us. However, we can just replace the LHS or RHS with the constant.
if (BlocksToFoldInto.size() ==
cast<PHINode>(BB->front()).getNumIncomingValues()) {
- if (SplitVal == 0) {
+ if (!SplitVal) {
// If all preds provide undef, just nuke the xor, because it is undef too.
BO->replaceAllUsesWith(UndefValue::get(BO->getType()));
BO->eraseFromParent();
@@ -1531,7 +1532,7 @@ bool JumpThreading::DuplicateCondBranchOnPHIIntoPred(BasicBlock *BB,
// can just clone the bits from BB into the end of the new PredBB.
BranchInst *OldPredBranch = dyn_cast<BranchInst>(PredBB->getTerminator());
- if (OldPredBranch == 0 || !OldPredBranch->isUnconditional()) {
+ if (!OldPredBranch || !OldPredBranch->isUnconditional()) {
PredBB = SplitEdge(PredBB, BB, this);
OldPredBranch = cast<BranchInst>(PredBB->getTerminator());
}
generated by cgit v1.1 at 2024-05-18 02:44:21 +0000