// If this value is named, destroy the name. This should not be in a symtab
// at this point.
- if (Name)
+ if (Name && SubclassID != MDStringVal)
Name->Destroy();
// There should be no uses of this object anymore, remove it.
/// isUsedInBasicBlock - Return true if this value is used in the specified
/// basic block.
bool Value::isUsedInBasicBlock(const BasicBlock *BB) const {
+ // Start by scanning over the instructions looking for a use before we start
+ // the expensive use iteration.
+ unsigned MaxBlockSize = 3;
+ for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I != E; ++I) {
+ if (std::find(I->op_begin(), I->op_end(), this) != I->op_end())
+ return true;
+ if (MaxBlockSize-- == 0) // If the block is larger fall back to use_iterator
+ break;
+ }
+
+ if (MaxBlockSize != 0) // We scanned the entire block and found no use.
+ return false;
+
for (const_use_iterator I = use_begin(), E = use_end(); I != E; ++I) {
const Instruction *User = dyn_cast<Instruction>(*I);
if (User && User->getParent() == BB)
}
void Value::setName(const Twine &NewName) {
+ assert(SubclassID != MDStringVal &&
+ "Cannot set the name of MDString with this method!");
+
// Fast path for common IRBuilder case of setName("") when there is no name.
if (NewName.isTriviallyEmpty() && !hasName())
return;
/// takeName - transfer the name from V to this value, setting V's name to
/// empty. It is an error to call V->takeName(V).
void Value::takeName(Value *V) {
+ assert(SubclassID != MDStringVal && "Cannot take the name of an MDString!");
+
ValueSymbolTable *ST = 0;
// If this value has a name, drop it.
if (hasName()) {
BB->replaceSuccessorsPhiUsesWith(cast<BasicBlock>(New));
}
-Value *Value::stripPointerCasts() {
- if (!getType()->isPointerTy())
- return this;
+namespace {
+// Various metrics for how much to strip off of pointers.
+enum PointerStripKind {
+ PSK_ZeroIndices,
+ PSK_InBoundsConstantIndices,
+ PSK_InBounds
+};
+
+template <PointerStripKind StripKind>
+static Value *stripPointerCastsAndOffsets(Value *V) {
+ if (!V->getType()->isPointerTy())
+ return V;
// Even though we don't look through PHI nodes, we could be called on an
// instruction in an unreachable block, which may be on a cycle.
SmallPtrSet<Value *, 4> Visited;
- Value *V = this;
Visited.insert(V);
do {
if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) {
- if (!GEP->hasAllZeroIndices())
- return V;
+ switch (StripKind) {
+ case PSK_ZeroIndices:
+ if (!GEP->hasAllZeroIndices())
+ return V;
+ break;
+ case PSK_InBoundsConstantIndices:
+ if (!GEP->hasAllConstantIndices())
+ return V;
+ // fallthrough
+ case PSK_InBounds:
+ if (!GEP->isInBounds())
+ return V;
+ break;
+ }
V = GEP->getPointerOperand();
} else if (Operator::getOpcode(V) == Instruction::BitCast) {
V = cast<Operator>(V)->getOperand(0);
return V;
}
+} // namespace
+
+Value *Value::stripPointerCasts() {
+ return stripPointerCastsAndOffsets<PSK_ZeroIndices>(this);
+}
+
+Value *Value::stripInBoundsConstantOffsets() {
+ return stripPointerCastsAndOffsets<PSK_InBoundsConstantIndices>(this);
+}
+
+Value *Value::stripInBoundsOffsets() {
+ return stripPointerCastsAndOffsets<PSK_InBounds>(this);
+}
/// isDereferenceablePointer - Test if this value is always a pointer to
/// allocated and suitably aligned memory for a simple load or store.
-bool Value::isDereferenceablePointer() const {
+static bool isDereferenceablePointer(const Value *V,
+ SmallPtrSet<const Value *, 32> &Visited) {
// Note that it is not safe to speculate into a malloc'd region because
// malloc may return null.
// It's also not always safe to follow a bitcast, for example:
// be handled using TargetData to check sizes and alignments though.
// These are obviously ok.
- if (isa<AllocaInst>(this)) return true;
+ if (isa<AllocaInst>(V)) return true;
// Global variables which can't collapse to null are ok.
- if (const GlobalVariable *GV = dyn_cast<GlobalVariable>(this))
+ if (const GlobalVariable *GV = dyn_cast<GlobalVariable>(V))
return !GV->hasExternalWeakLinkage();
// byval arguments are ok.
- if (const Argument *A = dyn_cast<Argument>(this))
+ if (const Argument *A = dyn_cast<Argument>(V))
return A->hasByValAttr();
-
+
// For GEPs, determine if the indexing lands within the allocated object.
- if (const GEPOperator *GEP = dyn_cast<GEPOperator>(this)) {
+ if (const GEPOperator *GEP = dyn_cast<GEPOperator>(V)) {
// Conservatively require that the base pointer be fully dereferenceable.
- if (!GEP->getOperand(0)->isDereferenceablePointer())
+ if (!Visited.insert(GEP->getOperand(0)))
+ return false;
+ if (!isDereferenceablePointer(GEP->getOperand(0), Visited))
return false;
// Check the indices.
gep_type_iterator GTI = gep_type_begin(GEP);
return false;
}
+/// isDereferenceablePointer - Test if this value is always a pointer to
+/// allocated and suitably aligned memory for a simple load or store.
+bool Value::isDereferenceablePointer() const {
+ SmallPtrSet<const Value *, 32> Visited;
+ return ::isDereferenceablePointer(this, Visited);
+}
+
/// DoPHITranslation - If this value is a PHI node with CurBB as its parent,
/// return the value in the PHI node corresponding to PredBB. If not, return
/// ourself. This is useful if you want to know the value something has in a
setPrevPtr(List);
if (Next) {
Next->setPrevPtr(&Next);
- assert(VP == Next->VP && "Added to wrong list?");
+ assert(VP.getPointer() == Next->VP.getPointer() && "Added to wrong list?");
}
}
/// AddToUseList - Add this ValueHandle to the use list for VP.
void ValueHandleBase::AddToUseList() {
- assert(VP && "Null pointer doesn't have a use list!");
+ assert(VP.getPointer() && "Null pointer doesn't have a use list!");
- LLVMContextImpl *pImpl = VP->getContext().pImpl;
+ LLVMContextImpl *pImpl = VP.getPointer()->getContext().pImpl;
- if (VP->HasValueHandle) {
+ if (VP.getPointer()->HasValueHandle) {
// If this value already has a ValueHandle, then it must be in the
// ValueHandles map already.
- ValueHandleBase *&Entry = pImpl->ValueHandles[VP];
+ ValueHandleBase *&Entry = pImpl->ValueHandles[VP.getPointer()];
assert(Entry != 0 && "Value doesn't have any handles?");
AddToExistingUseList(&Entry);
return;
DenseMap<Value*, ValueHandleBase*> &Handles = pImpl->ValueHandles;
const void *OldBucketPtr = Handles.getPointerIntoBucketsArray();
- ValueHandleBase *&Entry = Handles[VP];
+ ValueHandleBase *&Entry = Handles[VP.getPointer()];
assert(Entry == 0 && "Value really did already have handles?");
AddToExistingUseList(&Entry);
- VP->HasValueHandle = true;
+ VP.getPointer()->HasValueHandle = true;
// If reallocation didn't happen or if this was the first insertion, don't
// walk the table.
// Okay, reallocation did happen. Fix the Prev Pointers.
for (DenseMap<Value*, ValueHandleBase*>::iterator I = Handles.begin(),
E = Handles.end(); I != E; ++I) {
- assert(I->second && I->first == I->second->VP && "List invariant broken!");
+ assert(I->second && I->first == I->second->VP.getPointer() &&
+ "List invariant broken!");
I->second->setPrevPtr(&I->second);
}
}
/// RemoveFromUseList - Remove this ValueHandle from its current use list.
void ValueHandleBase::RemoveFromUseList() {
- assert(VP && VP->HasValueHandle && "Pointer doesn't have a use list!");
+ assert(VP.getPointer() && VP.getPointer()->HasValueHandle &&
+ "Pointer doesn't have a use list!");
// Unlink this from its use list.
ValueHandleBase **PrevPtr = getPrevPtr();
// If the Next pointer was null, then it is possible that this was the last
// ValueHandle watching VP. If so, delete its entry from the ValueHandles
// map.
- LLVMContextImpl *pImpl = VP->getContext().pImpl;
+ LLVMContextImpl *pImpl = VP.getPointer()->getContext().pImpl;
DenseMap<Value*, ValueHandleBase*> &Handles = pImpl->ValueHandles;
if (Handles.isPointerIntoBucketsArray(PrevPtr)) {
- Handles.erase(VP);
- VP->HasValueHandle = false;
+ Handles.erase(VP.getPointer());
+ VP.getPointer()->HasValueHandle = false;
}
}
#endif
}
-/// ~CallbackVH. Empty, but defined here to avoid emitting the vtable
-/// more than once.
-CallbackVH::~CallbackVH() {}
+// Default implementation for CallbackVH.
+void CallbackVH::allUsesReplacedWith(Value *) {}
+
+void CallbackVH::deleted() {
+ setValPtr(NULL);
+}
projects / oota-llvm.git / blobdiff