+
+ /// PointerUnion4 - This is a pointer union of four pointer types. See
+ /// documentation for PointerUnion for usage.
+ template <typename PT1, typename PT2, typename PT3, typename PT4>
+ class PointerUnion4 {
+ public:
+ typedef PointerUnion<PT1, PT2> InnerUnion1;
+ typedef PointerUnion<PT3, PT4> InnerUnion2;
+ typedef PointerUnion<InnerUnion1, InnerUnion2> ValTy;
+ private:
+ ValTy Val;
+ public:
+ PointerUnion4() {}
+
+ PointerUnion4(PT1 V) {
+ Val = InnerUnion1(V);
+ }
+ PointerUnion4(PT2 V) {
+ Val = InnerUnion1(V);
+ }
+ PointerUnion4(PT3 V) {
+ Val = InnerUnion2(V);
+ }
+ PointerUnion4(PT4 V) {
+ Val = InnerUnion2(V);
+ }
+
+ /// isNull - Return true if the pointer held in the union is null,
+ /// regardless of which type it is.
+ bool isNull() const { return Val.isNull(); }
+ LLVM_EXPLICIT operator bool() const { return !isNull(); }
+
+ /// is<T>() return true if the Union currently holds the type matching T.
+ template<typename T>
+ int is() const {
+ // If T is PT1/PT2 choose InnerUnion1 otherwise choose InnerUnion2.
+ typedef typename
+ ::llvm::PointerUnionTypeSelector<PT1, T, InnerUnion1,
+ ::llvm::PointerUnionTypeSelector<PT2, T, InnerUnion1, InnerUnion2 >
+ >::Return Ty;
+ return Val.template is<Ty>() &&
+ Val.template get<Ty>().template is<T>();
+ }
+
+ /// get<T>() - Return the value of the specified pointer type. If the
+ /// specified pointer type is incorrect, assert.
+ template<typename T>
+ T get() const {
+ assert(is<T>() && "Invalid accessor called");
+ // If T is PT1/PT2 choose InnerUnion1 otherwise choose InnerUnion2.
+ typedef typename
+ ::llvm::PointerUnionTypeSelector<PT1, T, InnerUnion1,
+ ::llvm::PointerUnionTypeSelector<PT2, T, InnerUnion1, InnerUnion2 >
+ >::Return Ty;
+ return Val.template get<Ty>().template get<T>();
+ }
+
+ /// dyn_cast<T>() - If the current value is of the specified pointer type,
+ /// return it, otherwise return null.
+ template<typename T>
+ T dyn_cast() const {
+ if (is<T>()) return get<T>();
+ return T();
+ }
+
+ /// \brief Assignment from nullptr which just clears the union.
+ const PointerUnion4 &operator=(std::nullptr_t) {
+ Val = nullptr;
+ return *this;
+ }
+
+ /// Assignment operators - Allow assigning into this union from either
+ /// pointer type, setting the discriminator to remember what it came from.
+ const PointerUnion4 &operator=(const PT1 &RHS) {
+ Val = InnerUnion1(RHS);
+ return *this;
+ }
+ const PointerUnion4 &operator=(const PT2 &RHS) {
+ Val = InnerUnion1(RHS);
+ return *this;
+ }
+ const PointerUnion4 &operator=(const PT3 &RHS) {
+ Val = InnerUnion2(RHS);
+ return *this;
+ }
+ const PointerUnion4 &operator=(const PT4 &RHS) {
+ Val = InnerUnion2(RHS);
+ return *this;
+ }
+
+ void *getOpaqueValue() const { return Val.getOpaqueValue(); }
+ static inline PointerUnion4 getFromOpaqueValue(void *VP) {
+ PointerUnion4 V;
+ V.Val = ValTy::getFromOpaqueValue(VP);
+ return V;
+ }
+ };
+
+ // Teach SmallPtrSet that PointerUnion4 is "basically a pointer", that has
+ // # low bits available = min(PT1bits,PT2bits,PT2bits)-2.
+ template<typename PT1, typename PT2, typename PT3, typename PT4>
+ class PointerLikeTypeTraits<PointerUnion4<PT1, PT2, PT3, PT4> > {
+ public:
+ static inline void *
+ getAsVoidPointer(const PointerUnion4<PT1, PT2, PT3, PT4> &P) {
+ return P.getOpaqueValue();
+ }
+ static inline PointerUnion4<PT1, PT2, PT3, PT4>
+ getFromVoidPointer(void *P) {
+ return PointerUnion4<PT1, PT2, PT3, PT4>::getFromOpaqueValue(P);
+ }
+
+ // The number of bits available are the min of the two pointer types.
+ enum {
+ NumLowBitsAvailable =
+ PointerLikeTypeTraits<typename PointerUnion4<PT1, PT2, PT3, PT4>::ValTy>
+ ::NumLowBitsAvailable
+ };
+ };
+
+ // Teach DenseMap how to use PointerUnions as keys.
+ template<typename T, typename U>
+ struct DenseMapInfo<PointerUnion<T, U> > {
+ typedef PointerUnion<T, U> Pair;
+ typedef DenseMapInfo<T> FirstInfo;
+ typedef DenseMapInfo<U> SecondInfo;
+
+ static inline Pair getEmptyKey() {
+ return Pair(FirstInfo::getEmptyKey());
+ }
+ static inline Pair getTombstoneKey() {
+ return Pair(FirstInfo::getTombstoneKey());
+ }
+ static unsigned getHashValue(const Pair &PairVal) {
+ intptr_t key = (intptr_t)PairVal.getOpaqueValue();
+ return DenseMapInfo<intptr_t>::getHashValue(key);
+ }
+ static bool isEqual(const Pair &LHS, const Pair &RHS) {
+ return LHS.template is<T>() == RHS.template is<T>() &&
+ (LHS.template is<T>() ?
+ FirstInfo::isEqual(LHS.template get<T>(),
+ RHS.template get<T>()) :
+ SecondInfo::isEqual(LHS.template get<U>(),
+ RHS.template get<U>()));
+ }
+ };