mirror of
				https://github.com/c64scene-ar/llvm-6502.git
				synced 2025-10-27 09:17:11 +00:00 
			
		
		
		
	git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127153 91177308-0d34-0410-b5e6-96231b3b80d8
		
			
				
	
	
		
			446 lines
		
	
	
		
			15 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			446 lines
		
	
	
		
			15 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| //===- llvm/ADT/PointerUnion.h - Discriminated Union of 2 Ptrs --*- C++ -*-===//
 | |
| //
 | |
| //                     The LLVM Compiler Infrastructure
 | |
| //
 | |
| // This file is distributed under the University of Illinois Open Source
 | |
| // License. See LICENSE.TXT for details.
 | |
| //
 | |
| //===----------------------------------------------------------------------===//
 | |
| //
 | |
| // This file defines the PointerUnion class, which is a discriminated union of
 | |
| // pointer types.
 | |
| //
 | |
| //===----------------------------------------------------------------------===//
 | |
| 
 | |
| #ifndef LLVM_ADT_POINTERUNION_H
 | |
| #define LLVM_ADT_POINTERUNION_H
 | |
| 
 | |
| #include "llvm/ADT/PointerIntPair.h"
 | |
| 
 | |
| namespace llvm {
 | |
| 
 | |
|   template <typename T>
 | |
|   struct PointerUnionTypeSelectorReturn {
 | |
|     typedef T Return;
 | |
|   };
 | |
| 
 | |
|   /// \brief Get a type based on whether two types are the same or not. For:
 | |
|   /// @code
 | |
|   /// typedef typename PointerUnionTypeSelector<T1, T2, EQ, NE>::Return Ret;
 | |
|   /// @endcode
 | |
|   /// Ret will be EQ type if T1 is same as T2 or NE type otherwise.
 | |
|   template <typename T1, typename T2, typename RET_EQ, typename RET_NE>
 | |
|   struct PointerUnionTypeSelector {
 | |
|     typedef typename PointerUnionTypeSelectorReturn<RET_NE>::Return Return;
 | |
|   };
 | |
| 
 | |
|   template <typename T, typename RET_EQ, typename RET_NE>
 | |
|   struct PointerUnionTypeSelector<T, T, RET_EQ, RET_NE> {
 | |
|     typedef typename PointerUnionTypeSelectorReturn<RET_EQ>::Return Return;
 | |
|   };
 | |
| 
 | |
|   template <typename T1, typename T2, typename RET_EQ, typename RET_NE>
 | |
|   struct PointerUnionTypeSelectorReturn<
 | |
|                             PointerUnionTypeSelector<T1, T2, RET_EQ, RET_NE> > {
 | |
|     typedef typename PointerUnionTypeSelector<T1, T2, RET_EQ, RET_NE>::Return
 | |
|         Return;
 | |
|   };
 | |
| 
 | |
|   /// Provide PointerLikeTypeTraits for void* that is used by PointerUnion
 | |
|   /// for the two template arguments.
 | |
|   template <typename PT1, typename PT2>
 | |
|   class PointerUnionUIntTraits {
 | |
|   public:
 | |
|     static inline void *getAsVoidPointer(void *P) { return P; }
 | |
|     static inline void *getFromVoidPointer(void *P) { return P; }
 | |
|     enum {
 | |
|       PT1BitsAv = PointerLikeTypeTraits<PT1>::NumLowBitsAvailable,
 | |
|       PT2BitsAv = PointerLikeTypeTraits<PT2>::NumLowBitsAvailable,
 | |
|       NumLowBitsAvailable = PT1BitsAv < PT2BitsAv ? PT1BitsAv : PT2BitsAv
 | |
|     };
 | |
|   };
 | |
|   
 | |
|   /// PointerUnion - This implements a discriminated union of two pointer types,
 | |
|   /// and keeps the discriminator bit-mangled into the low bits of the pointer.
 | |
|   /// This allows the implementation to be extremely efficient in space, but
 | |
|   /// permits a very natural and type-safe API.
 | |
|   ///
 | |
|   /// Common use patterns would be something like this:
 | |
|   ///    PointerUnion<int*, float*> P;
 | |
|   ///    P = (int*)0;
 | |
|   ///    printf("%d %d", P.is<int*>(), P.is<float*>());  // prints "1 0"
 | |
|   ///    X = P.get<int*>();     // ok.
 | |
|   ///    Y = P.get<float*>();   // runtime assertion failure.
 | |
|   ///    Z = P.get<double*>();  // runtime assertion failure (regardless of tag)
 | |
|   ///    P = (float*)0;
 | |
|   ///    Y = P.get<float*>();   // ok.
 | |
|   ///    X = P.get<int*>();     // runtime assertion failure.
 | |
|   template <typename PT1, typename PT2>
 | |
|   class PointerUnion {
 | |
|   public:
 | |
|     typedef PointerIntPair<void*, 1, bool, 
 | |
|                            PointerUnionUIntTraits<PT1,PT2> > ValTy;
 | |
|   private:
 | |
|     ValTy Val;
 | |
| 
 | |
|     struct IsPT1 {
 | |
|       static const int Num = 0;
 | |
|     };
 | |
|     struct IsPT2 {
 | |
|       static const int Num = 1;
 | |
|     };
 | |
|     template <typename T>
 | |
|     struct UNION_DOESNT_CONTAIN_TYPE { };
 | |
| 
 | |
|   public:
 | |
|     PointerUnion() {}
 | |
|     
 | |
|     PointerUnion(PT1 V) {
 | |
|       Val.setPointer(
 | |
|          const_cast<void *>(PointerLikeTypeTraits<PT1>::getAsVoidPointer(V)));
 | |
|       Val.setInt(0);
 | |
|     }
 | |
|     PointerUnion(PT2 V) {
 | |
|       Val.setPointer(
 | |
|          const_cast<void *>(PointerLikeTypeTraits<PT2>::getAsVoidPointer(V)));
 | |
|       Val.setInt(1);
 | |
|     }
 | |
|     
 | |
|     /// isNull - Return true if the pointer held 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 {
 | |
|       typedef typename
 | |
|         ::llvm::PointerUnionTypeSelector<PT1, T, IsPT1,
 | |
|           ::llvm::PointerUnionTypeSelector<PT2, T, IsPT2,
 | |
|                                     UNION_DOESNT_CONTAIN_TYPE<T> > >::Return Ty;
 | |
|       int TyNo = Ty::Num;
 | |
|       return static_cast<int>(Val.getInt()) == TyNo;
 | |
|     }
 | |
|     
 | |
|     /// 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");
 | |
|       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 get<T>();
 | |
|       return T();
 | |
|     }
 | |
| 
 | |
|     /// \brief If the union is set to the first pointer type we can get an
 | |
|     /// address pointing to it.
 | |
|     template <typename T>
 | |
|     PT1 const *getAddrOf() const {
 | |
|       assert(is<PT1>() && "Val is not the first pointer");
 | |
|       assert(get<PT1>() == Val.getPointer() &&
 | |
|          "Can't get the address because PointerLikeTypeTraits changes the ptr");
 | |
|       T const *can_only_get_address_of_first_pointer_type
 | |
|                         = reinterpret_cast<PT1 const *>(Val.getAddrOfPointer());
 | |
|       return can_only_get_address_of_first_pointer_type;
 | |
|     }
 | |
|     
 | |
|     /// 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(
 | |
|          const_cast<void *>(PointerLikeTypeTraits<PT1>::getAsVoidPointer(RHS)));
 | |
|       Val.setInt(0);
 | |
|       return *this;
 | |
|     }
 | |
|     const PointerUnion &operator=(const PT2 &RHS) {
 | |
|       Val.setPointer(
 | |
|         const_cast<void *>(PointerLikeTypeTraits<PT2>::getAsVoidPointer(RHS)));
 | |
|       Val.setInt(1);
 | |
|       return *this;
 | |
|     }
 | |
|     
 | |
|     void *getOpaqueValue() const { return Val.getOpaqueValue(); }
 | |
|     static inline PointerUnion getFromOpaqueValue(void *VP) {
 | |
|       PointerUnion V;
 | |
|       V.Val = ValTy::getFromOpaqueValue(VP);
 | |
|       return V;
 | |
|     }
 | |
|   };
 | |
|   
 | |
|   // 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> > {
 | |
|   public:
 | |
|     static inline void *
 | |
|     getAsVoidPointer(const PointerUnion<PT1, PT2> &P) {
 | |
|       return P.getOpaqueValue();
 | |
|     }
 | |
|     static inline PointerUnion<PT1, PT2>
 | |
|     getFromVoidPointer(void *P) {
 | |
|       return PointerUnion<PT1, PT2>::getFromOpaqueValue(P);
 | |
|     }
 | |
|     
 | |
|     // The number of bits available are the min of the two pointer types.
 | |
|     enum {
 | |
|       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;
 | |
| 
 | |
|     struct IsInnerUnion {
 | |
|       ValTy Val;
 | |
|       IsInnerUnion(ValTy val) : Val(val) { }
 | |
|       template<typename T>
 | |
|       int is() const {
 | |
|         return Val.template is<InnerUnion>() && 
 | |
|                Val.template get<InnerUnion>().template is<T>();
 | |
|       }
 | |
|       template<typename T>
 | |
|       T get() const {
 | |
|         return Val.template get<InnerUnion>().template get<T>();
 | |
|       }
 | |
|     };
 | |
| 
 | |
|     struct IsPT3 {
 | |
|       ValTy Val;
 | |
|       IsPT3(ValTy val) : Val(val) { }
 | |
|       template<typename T>
 | |
|       int is() const {
 | |
|         return Val.template is<T>();
 | |
|       }
 | |
|       template<typename T>
 | |
|       T get() const {
 | |
|         return Val.template get<T>();
 | |
|       }
 | |
|     };
 | |
| 
 | |
|   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 held 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 {
 | |
|       // If T is PT1/PT2 choose IsInnerUnion otherwise choose IsPT3.
 | |
|       typedef typename
 | |
|         ::llvm::PointerUnionTypeSelector<PT1, T, IsInnerUnion,
 | |
|           ::llvm::PointerUnionTypeSelector<PT2, T, IsInnerUnion, IsPT3 >
 | |
|                                                                    >::Return Ty;
 | |
|       return Ty(Val).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 IsInnerUnion otherwise choose IsPT3.
 | |
|       typedef typename
 | |
|         ::llvm::PointerUnionTypeSelector<PT1, T, IsInnerUnion,
 | |
|           ::llvm::PointerUnionTypeSelector<PT2, T, IsInnerUnion, IsPT3 >
 | |
|                                                                    >::Return Ty;
 | |
|       return Ty(Val).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 inline 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
 | |
|     };
 | |
|   };
 | |
| 
 | |
|   /// 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(); }
 | |
|     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();
 | |
|     }
 | |
|     
 | |
|     /// 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
 | |
|     };
 | |
|   };
 | |
| }
 | |
| 
 | |
| #endif
 |