enum { NumLowBitsAvailable = 2 };
};
-/// ValueHandleBase - This is the common base class of value handles.
+/// \brief This is the common base class of value handles.
+///
/// ValueHandle's are smart pointers to Value's that have special behavior when
/// the value is deleted or ReplaceAllUsesWith'd. See the specific handles
/// below for details.
-///
class ValueHandleBase {
friend class Value;
protected:
- /// HandleBaseKind - This indicates what sub class the handle actually is.
+ /// \brief This indicates what sub class the handle actually is.
+ ///
/// This is to avoid having a vtable for the light-weight handle pointers. The
/// fully general Callback version does have a vtable.
enum HandleBaseKind {
Weak
};
+ ValueHandleBase(const ValueHandleBase &RHS)
+ : ValueHandleBase(RHS.PrevPair.getInt(), RHS) {}
+
+ ValueHandleBase(HandleBaseKind Kind, const ValueHandleBase &RHS)
+ : PrevPair(nullptr, Kind), Next(nullptr), V(RHS.V) {
+ if (isValid(V))
+ AddToExistingUseList(RHS.getPrevPtr());
+ }
+
private:
PointerIntPair<ValueHandleBase**, 2, HandleBaseKind> PrevPair;
ValueHandleBase *Next;
- // A subclass may want to store some information along with the value
- // pointer. Allow them to do this by making the value pointer a pointer-int
- // pair. The 'setValPtrInt' and 'getValPtrInt' methods below give them this
- // access.
- PointerIntPair<Value*, 2> VP;
+ Value* V;
- ValueHandleBase(const ValueHandleBase&) LLVM_DELETED_FUNCTION;
public:
explicit ValueHandleBase(HandleBaseKind Kind)
- : PrevPair(nullptr, Kind), Next(nullptr), VP(nullptr, 0) {}
+ : PrevPair(nullptr, Kind), Next(nullptr), V(nullptr) {}
ValueHandleBase(HandleBaseKind Kind, Value *V)
- : PrevPair(nullptr, Kind), Next(nullptr), VP(V, 0) {
- if (isValid(VP.getPointer()))
+ : PrevPair(nullptr, Kind), Next(nullptr), V(V) {
+ if (isValid(V))
AddToUseList();
}
- ValueHandleBase(HandleBaseKind Kind, const ValueHandleBase &RHS)
- : PrevPair(nullptr, Kind), Next(nullptr), VP(RHS.VP) {
- if (isValid(VP.getPointer()))
- AddToExistingUseList(RHS.getPrevPtr());
- }
+
~ValueHandleBase() {
- if (isValid(VP.getPointer()))
+ if (isValid(V))
RemoveFromUseList();
}
Value *operator=(Value *RHS) {
- if (VP.getPointer() == RHS) return RHS;
- if (isValid(VP.getPointer())) RemoveFromUseList();
- VP.setPointer(RHS);
- if (isValid(VP.getPointer())) AddToUseList();
+ if (V == RHS) return RHS;
+ if (isValid(V)) RemoveFromUseList();
+ V = RHS;
+ if (isValid(V)) AddToUseList();
return RHS;
}
Value *operator=(const ValueHandleBase &RHS) {
- if (VP.getPointer() == RHS.VP.getPointer()) return RHS.VP.getPointer();
- if (isValid(VP.getPointer())) RemoveFromUseList();
- VP.setPointer(RHS.VP.getPointer());
- if (isValid(VP.getPointer())) AddToExistingUseList(RHS.getPrevPtr());
- return VP.getPointer();
+ if (V == RHS.V) return RHS.V;
+ if (isValid(V)) RemoveFromUseList();
+ V = RHS.V;
+ if (isValid(V)) AddToExistingUseList(RHS.getPrevPtr());
+ return V;
}
- Value *operator->() const { return getValPtr(); }
- Value &operator*() const { return *getValPtr(); }
+ Value *operator->() const { return V; }
+ Value &operator*() const { return *V; }
protected:
- Value *getValPtr() const { return VP.getPointer(); }
-
- void setValPtrInt(unsigned K) { VP.setInt(K); }
- unsigned getValPtrInt() const { return VP.getInt(); }
+ Value *getValPtr() const { return V; }
static bool isValid(Value *V) {
return V &&
HandleBaseKind getKind() const { return PrevPair.getInt(); }
void setPrevPtr(ValueHandleBase **Ptr) { PrevPair.setPointer(Ptr); }
- /// AddToExistingUseList - Add this ValueHandle to the use list for VP, where
+ /// \brief Add this ValueHandle to the use list for V.
+ ///
/// List is the address of either the head of the list or a Next node within
/// the existing use list.
void AddToExistingUseList(ValueHandleBase **List);
- /// AddToExistingUseListAfter - Add this ValueHandle to the use list after
- /// Node.
+ /// \brief Add this ValueHandle to the use list after Node.
void AddToExistingUseListAfter(ValueHandleBase *Node);
- /// AddToUseList - Add this ValueHandle to the use list for VP.
+ /// \brief Add this ValueHandle to the use list for V.
void AddToUseList();
- /// RemoveFromUseList - Remove this ValueHandle from its current use list.
+ /// \brief Remove this ValueHandle from its current use list.
void RemoveFromUseList();
};
-/// WeakVH - This is a value handle that tries hard to point to a Value, even
-/// across RAUW operations, but will null itself out if the value is destroyed.
-/// this is useful for advisory sorts of information, but should not be used as
-/// the key of a map (since the map would have to rearrange itself when the
-/// pointer changes).
+/// \brief Value handle that is nullable, but tries to track the Value.
+///
+/// This is a value handle that tries hard to point to a Value, even across
+/// RAUW operations, but will null itself out if the value is destroyed. this
+/// is useful for advisory sorts of information, but should not be used as the
+/// key of a map (since the map would have to rearrange itself when the pointer
+/// changes).
class WeakVH : public ValueHandleBase {
public:
WeakVH() : ValueHandleBase(Weak) {}
WeakVH(const WeakVH &RHS)
: ValueHandleBase(Weak, RHS) {}
+ WeakVH &operator=(const WeakVH &RHS) = default;
+
Value *operator=(Value *RHS) {
return ValueHandleBase::operator=(RHS);
}
// Specialize simplify_type to allow WeakVH to participate in
// dyn_cast, isa, etc.
-template<> struct simplify_type<WeakVH> {
- typedef Value* SimpleType;
- static SimpleType getSimplifiedValue(WeakVH &WVH) {
- return WVH;
- }
+template <> struct simplify_type<WeakVH> {
+ typedef Value *SimpleType;
+ static SimpleType getSimplifiedValue(WeakVH &WVH) { return WVH; }
+};
+template <> struct simplify_type<const WeakVH> {
+ typedef Value *SimpleType;
+ static SimpleType getSimplifiedValue(const WeakVH &WVH) { return WVH; }
};
-/// AssertingVH - This is a Value Handle that points to a value and asserts out
-/// if the value is destroyed while the handle is still live. This is very
-/// useful for catching dangling pointer bugs and other things which can be
-/// non-obvious. One particularly useful place to use this is as the Key of a
-/// map. Dangling pointer bugs often lead to really subtle bugs that only occur
-/// if another object happens to get allocated to the same address as the old
-/// one. Using an AssertingVH ensures that an assert is triggered as soon as
-/// the bad delete occurs.
+/// \brief Value handle that asserts if the Value is deleted.
+///
+/// This is a Value Handle that points to a value and asserts out if the value
+/// is destroyed while the handle is still live. This is very useful for
+/// catching dangling pointer bugs and other things which can be non-obvious.
+/// One particularly useful place to use this is as the Key of a map. Dangling
+/// pointer bugs often lead to really subtle bugs that only occur if another
+/// object happens to get allocated to the same address as the old one. Using
+/// an AssertingVH ensures that an assert is triggered as soon as the bad
+/// delete occurs.
///
/// Note that an AssertingVH handle does *not* follow values across RAUW
/// operations. This means that RAUW's need to explicitly update the
: public ValueHandleBase
#endif
{
+ friend struct DenseMapInfo<AssertingVH<ValueTy> >;
#ifndef NDEBUG
- ValueTy *getValPtr() const {
- return static_cast<ValueTy*>(ValueHandleBase::getValPtr());
- }
- void setValPtr(ValueTy *P) {
- ValueHandleBase::operator=(GetAsValue(P));
- }
+ Value *getRawValPtr() const { return ValueHandleBase::getValPtr(); }
+ void setRawValPtr(Value *P) { ValueHandleBase::operator=(P); }
#else
- ValueTy *ThePtr;
- ValueTy *getValPtr() const { return ThePtr; }
- void setValPtr(ValueTy *P) { ThePtr = P; }
+ Value *ThePtr;
+ Value *getRawValPtr() const { return ThePtr; }
+ void setRawValPtr(Value *P) { ThePtr = P; }
#endif
-
- // Convert a ValueTy*, which may be const, to the type the base
- // class expects.
+ // Convert a ValueTy*, which may be const, to the raw Value*.
static Value *GetAsValue(Value *V) { return V; }
static Value *GetAsValue(const Value *V) { return const_cast<Value*>(V); }
+ ValueTy *getValPtr() const { return static_cast<ValueTy *>(getRawValPtr()); }
+ void setValPtr(ValueTy *P) { setRawValPtr(GetAsValue(P)); }
+
public:
#ifndef NDEBUG
AssertingVH() : ValueHandleBase(Assert) {}
AssertingVH(const AssertingVH &RHS) : ValueHandleBase(Assert, RHS) {}
#else
AssertingVH() : ThePtr(nullptr) {}
- AssertingVH(ValueTy *P) : ThePtr(P) {}
+ AssertingVH(ValueTy *P) : ThePtr(GetAsValue(P)) {}
#endif
operator ValueTy*() const {
// Specialize DenseMapInfo to allow AssertingVH to participate in DenseMap.
template<typename T>
struct DenseMapInfo<AssertingVH<T> > {
- typedef DenseMapInfo<T*> PointerInfo;
static inline AssertingVH<T> getEmptyKey() {
- return AssertingVH<T>(PointerInfo::getEmptyKey());
+ AssertingVH<T> Res;
+ Res.setRawValPtr(DenseMapInfo<Value *>::getEmptyKey());
+ return Res;
}
- static inline T* getTombstoneKey() {
- return AssertingVH<T>(PointerInfo::getTombstoneKey());
+ static inline AssertingVH<T> getTombstoneKey() {
+ AssertingVH<T> Res;
+ Res.setRawValPtr(DenseMapInfo<Value *>::getTombstoneKey());
+ return Res;
}
static unsigned getHashValue(const AssertingVH<T> &Val) {
- return PointerInfo::getHashValue(Val);
+ return DenseMapInfo<Value *>::getHashValue(Val.getRawValPtr());
}
static bool isEqual(const AssertingVH<T> &LHS, const AssertingVH<T> &RHS) {
- return LHS == RHS;
+ return DenseMapInfo<Value *>::isEqual(LHS.getRawValPtr(),
+ RHS.getRawValPtr());
}
};
-
+
template <typename T>
struct isPodLike<AssertingVH<T> > {
#ifdef NDEBUG
};
-/// TrackingVH - This is a value handle that tracks a Value (or Value subclass),
-/// even across RAUW operations.
+/// \brief Value handle that tracks a Value across RAUW.
///
/// TrackingVH is designed for situations where a client needs to hold a handle
/// to a Value (or subclass) across some operations which may move that value,
public:
TrackingVH() : ValueHandleBase(Tracking) {}
TrackingVH(ValueTy *P) : ValueHandleBase(Tracking, GetAsValue(P)) {}
- TrackingVH(const TrackingVH &RHS) : ValueHandleBase(Tracking, RHS) {}
operator ValueTy*() const {
return getValPtr();
setValPtr(RHS);
return getValPtr();
}
- ValueTy *operator=(const TrackingVH<ValueTy> &RHS) {
- setValPtr(RHS.getValPtr());
- return getValPtr();
- }
ValueTy *operator->() const { return getValPtr(); }
ValueTy &operator*() const { return *getValPtr(); }
};
-/// CallbackVH - This is a value handle that allows subclasses to define
-/// callbacks that run when the underlying Value has RAUW called on it or is
-/// destroyed. This class can be used as the key of a map, as long as the user
-/// takes it out of the map before calling setValPtr() (since the map has to
-/// rearrange itself when the pointer changes). Unlike ValueHandleBase, this
-/// class has a vtable and a virtual destructor.
+/// \brief Value handle with callbacks on RAUW and destruction.
+///
+/// This is a value handle that allows subclasses to define callbacks that run
+/// when the underlying Value has RAUW called on it or is destroyed. This
+/// class can be used as the key of a map, as long as the user takes it out of
+/// the map before calling setValPtr() (since the map has to rearrange itself
+/// when the pointer changes). Unlike ValueHandleBase, this class has a vtable.
class CallbackVH : public ValueHandleBase {
virtual void anchor();
protected:
- CallbackVH(const CallbackVH &RHS)
- : ValueHandleBase(Callback, RHS) {}
-
- virtual ~CallbackVH() {}
+ ~CallbackVH() = default;
+ CallbackVH(const CallbackVH &) = default;
+ CallbackVH &operator=(const CallbackVH &) = default;
void setValPtr(Value *P) {
ValueHandleBase::operator=(P);
return getValPtr();
}
- /// Called when this->getValPtr() is destroyed, inside ~Value(), so you may
- /// call any non-virtual Value method on getValPtr(), but no subclass methods.
- /// If WeakVH were implemented as a CallbackVH, it would use this method to
- /// call setValPtr(NULL). AssertingVH would use this method to cause an
- /// assertion failure.
+ /// \brief Callback for Value destruction.
+ ///
+ /// Called when this->getValPtr() is destroyed, inside ~Value(), so you
+ /// may call any non-virtual Value method on getValPtr(), but no subclass
+ /// methods. If WeakVH were implemented as a CallbackVH, it would use this
+ /// method to call setValPtr(NULL). AssertingVH would use this method to
+ /// cause an assertion failure.
///
/// All implementations must remove the reference from this object to the
/// Value that's being destroyed.
virtual void deleted() { setValPtr(nullptr); }
+ /// \brief Callback for Value RAUW.
+ ///
/// Called when this->getValPtr()->replaceAllUsesWith(new_value) is called,
/// _before_ any of the uses have actually been replaced. If WeakVH were
/// implemented as a CallbackVH, it would use this method to call