[llvm-commits] [llvm] r68056 - /llvm/trunk/include/llvm/ADT/PointerUnion.h
Chris Lattner
sabre at nondot.org
Mon Mar 30 13:29:27 PDT 2009
Author: lattner
Date: Mon Mar 30 15:29:27 2009
New Revision: 68056
URL: http://llvm.org/viewvc/llvm-project?rev=68056&view=rev
Log:
add a PointerUnion3 class and generalize PointerUnion to work with
anything pointer-like, which may or may not actually be a pointer.
Modified:
llvm/trunk/include/llvm/ADT/PointerUnion.h
Modified: llvm/trunk/include/llvm/ADT/PointerUnion.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/ADT/PointerUnion.h?rev=68056&r1=68055&r2=68056&view=diff
==============================================================================
--- llvm/trunk/include/llvm/ADT/PointerUnion.h (original)
+++ llvm/trunk/include/llvm/ADT/PointerUnion.h Mon Mar 30 15:29:27 2009
@@ -22,12 +22,11 @@
/// getPointerUnionTypeNum - If the argument has type PT1* or PT2* return
/// false or true respectively.
template <typename PT1, typename PT2>
- static inline bool getPointerUnionTypeNum(PT1 *P) { return false; }
+ static inline int getPointerUnionTypeNum(PT1 *P) { return 0; }
template <typename PT1, typename PT2>
- static inline bool getPointerUnionTypeNum(PT2 *P) { return true; }
- // Enable, if we could use static_assert.
- //template <typename PT1, typename PT2>
- //static inline bool getPointerUnionTypeNum(...) { abort() }
+ static inline int getPointerUnionTypeNum(PT2 *P) { return 1; }
+ template <typename PT1, typename PT2>
+ static inline int getPointerUnionTypeNum(...) { return -1; }
/// Provide PointerLikeTypeTraits for void* that is used by PointerUnion
@@ -70,22 +69,25 @@
PointerUnion() {}
PointerUnion(PT1 V) {
- Val.setPointer(V);
+ Val.setPointer(PointerLikeTypeTraits<PT1>::getAsVoidPointer(V));
Val.setInt(0);
}
PointerUnion(PT2 V) {
- Val.setPointer(V);
+ Val.setPointer(PointerLikeTypeTraits<PT2>::getAsVoidPointer(V));
Val.setInt(1);
}
/// isNull - Return true if the pointer help in the union is null,
/// regardless of which type it is.
bool isNull() const { return Val.getPointer() == 0; }
-
+ operator bool() const { return !isNull(); }
+
/// is<T>() return true if the Union currently holds the type matching T.
template<typename T>
int is() const {
- return Val.getInt() == ::llvm::getPointerUnionTypeNum<PT1, PT2>((T*)0);
+ int TyNo = ::llvm::getPointerUnionTypeNum<PT1, PT2>((T*)0);
+ assert(TyNo != -1 && "Type query could never succeed on PointerUnion!");
+ return Val.getInt() == TyNo;
}
/// get<T>() - Return the value of the specified pointer type. If the
@@ -93,26 +95,26 @@
template<typename T>
T get() const {
assert(is<T>() && "Invalid accessor called");
- return static_cast<T>(Val.getPointer());
+ return PointerLikeTypeTraits<T>::getFromVoidPointer(Val.getPointer());
}
/// 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 static_cast<T>(Val.getPointer());
+ if (is<T>()) return get<T>();
return T();
}
/// Assignment operators - Allow assigning into this union from either
/// pointer type, setting the discriminator to remember what it came from.
const PointerUnion &operator=(const PT1 &RHS) {
- Val.setPointer(RHS);
+ Val.setPointer(PointerLikeTypeTraits<PT1>::getAsVoidPointer(RHS));
Val.setInt(0);
return *this;
}
const PointerUnion &operator=(const PT2 &RHS) {
- Val.setPointer(RHS);
+ Val.setPointer(PointerLikeTypeTraits<PT2>::getAsVoidPointer(RHS));
Val.setInt(1);
return *this;
}
@@ -125,7 +127,7 @@
}
};
- // Teach SmallPtrSet that PointerIntPair is "basically a pointer", that has
+ // Teach SmallPtrSet that PointerUnion is "basically a pointer", that has
// # low bits available = min(PT1bits,PT2bits)-1.
template<typename PT1, typename PT2>
class PointerLikeTypeTraits<PointerUnion<PT1, PT2> > {
@@ -142,7 +144,110 @@
// The number of bits available are the min of the two pointer types.
enum {
NumLowBitsAvailable =
- PointerUnion<PT1,PT2>::ValTy::NumLowBitsAvailable
+ PointerLikeTypeTraits<typename PointerUnion<PT1,PT2>::ValTy>
+ ::NumLowBitsAvailable
+ };
+ };
+
+
+ /// PointerUnion3 - This is a pointer union of three pointer types. See
+ /// documentation for PointerUnion for usage.
+ template <typename PT1, typename PT2, typename PT3>
+ class PointerUnion3 {
+ public:
+ typedef PointerUnion<PT1, PT2> InnerUnion;
+ typedef PointerUnion<InnerUnion, PT3> ValTy;
+ private:
+ ValTy Val;
+ public:
+ PointerUnion3() {}
+
+ PointerUnion3(PT1 V) {
+ Val = InnerUnion(V);
+ }
+ PointerUnion3(PT2 V) {
+ Val = InnerUnion(V);
+ }
+ PointerUnion3(PT3 V) {
+ Val = V;
+ }
+
+ /// isNull - Return true if the pointer help in the union is null,
+ /// regardless of which type it is.
+ bool isNull() const { return Val.isNull(); }
+ operator bool() const { return !isNull(); }
+
+ /// is<T>() return true if the Union currently holds the type matching T.
+ template<typename T>
+ int is() const {
+ // Is it PT1/PT2?
+ if (::llvm::getPointerUnionTypeNum<PT1, PT2>((T*)0) != -1)
+ return Val.get<InnerUnion>().is<T>();
+ // Must be PT3 or statically invalid.
+ assert(Val.is<T>());
+ return true;
+ }
+
+ /// 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 (Val.is<T>())
+ return Val.get<T>();
+ return Val.get<InnerUnion>().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();
+ }
+
+ /// Assignment operators - Allow assigning into this union from either
+ /// pointer type, setting the discriminator to remember what it came from.
+ const PointerUnion3 &operator=(const PT1 &RHS) {
+ Val = InnerUnion(RHS);
+ return *this;
+ }
+ const PointerUnion3 &operator=(const PT2 &RHS) {
+ Val = InnerUnion(RHS);
+ return *this;
+ }
+ const PointerUnion3 &operator=(const PT3 &RHS) {
+ Val = RHS;
+ return *this;
+ }
+
+ void *getOpaqueValue() const { return Val.getOpaqueValue(); }
+ static PointerUnion3 getFromOpaqueValue(void *VP) {
+ PointerUnion3 V;
+ V.Val = ValTy::getFromOpaqueValue(VP);
+ return V;
+ }
+ };
+
+ // Teach SmallPtrSet that PointerUnion3 is "basically a pointer", that has
+ // # low bits available = min(PT1bits,PT2bits,PT2bits)-2.
+ template<typename PT1, typename PT2, typename PT3>
+ class PointerLikeTypeTraits<PointerUnion3<PT1, PT2, PT3> > {
+ public:
+ static inline void *
+ getAsVoidPointer(const PointerUnion3<PT1, PT2, PT3> &P) {
+ return P.getOpaqueValue();
+ }
+ static inline PointerUnion3<PT1, PT2, PT3>
+ getFromVoidPointer(void *P) {
+ return PointerUnion3<PT1, PT2, PT3>::getFromOpaqueValue(P);
+ }
+
+ // The number of bits available are the min of the two pointer types.
+ enum {
+ NumLowBitsAvailable =
+ PointerLikeTypeTraits<typename PointerUnion3<PT1, PT2, PT3>::ValTy>
+ ::NumLowBitsAvailable
};
};
}
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