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Diffstat (limited to 'include/Support/Casting.h')
| -rw-r--r-- | include/Support/Casting.h | 301 |
1 files changed, 0 insertions, 301 deletions
diff --git a/include/Support/Casting.h b/include/Support/Casting.h deleted file mode 100644 index abc80aac7a..0000000000 --- a/include/Support/Casting.h +++ /dev/null @@ -1,301 +0,0 @@ -//===-- Support/Casting.h - Allow flexible, checked, casts ------*- C++ -*-===// -// -// The LLVM Compiler Infrastructure -// -// This file was developed by the LLVM research group and is distributed under -// the University of Illinois Open Source License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file defines the isa<X>(), cast<X>(), dyn_cast<X>(), cast_or_null<X>(), -// and dyn_cast_or_null<X>() templates. -// -//===----------------------------------------------------------------------===// - -#ifndef SUPPORT_CASTING_H -#define SUPPORT_CASTING_H - -namespace llvm { - -//===----------------------------------------------------------------------===// -// isa<x> Support Templates -//===----------------------------------------------------------------------===// - -template<typename FromCl> struct isa_impl_cl; - -// Define a template that can be specialized by smart pointers to reflect the -// fact that they are automatically dereferenced, and are not involved with the -// template selection process... the default implementation is a noop. -// -template<typename From> struct simplify_type { - typedef From SimpleType; // The real type this represents... - - // An accessor to get the real value... - static SimpleType &getSimplifiedValue(From &Val) { return Val; } -}; - -template<typename From> struct simplify_type<const From> { - typedef const From SimpleType; - static SimpleType &getSimplifiedValue(const From &Val) { - return simplify_type<From>::getSimplifiedValue(static_cast<From&>(Val)); - } -}; - - -// isa<X> - Return true if the parameter to the template is an instance of the -// template type argument. Used like this: -// -// if (isa<Type*>(myVal)) { ... } -// -template <typename To, typename From> -inline bool isa_impl(const From &Val) { - return To::classof(&Val); -} - -template<typename To, typename From, typename SimpleType> -struct isa_impl_wrap { - // When From != SimplifiedType, we can simplify the type some more by using - // the simplify_type template. - static bool doit(const From &Val) { - return isa_impl_cl<const SimpleType>::template - isa<To>(simplify_type<const From>::getSimplifiedValue(Val)); - } -}; - -template<typename To, typename FromTy> -struct isa_impl_wrap<To, const FromTy, const FromTy> { - // When From == SimpleType, we are as simple as we are going to get. - static bool doit(const FromTy &Val) { - return isa_impl<To,FromTy>(Val); - } -}; - -// isa_impl_cl - Use class partial specialization to transform types to a single -// canonical form for isa_impl. -// -template<typename FromCl> -struct isa_impl_cl { - template<class ToCl> - static bool isa(const FromCl &Val) { - return isa_impl_wrap<ToCl,const FromCl, - typename simplify_type<const FromCl>::SimpleType>::doit(Val); - } -}; - -// Specialization used to strip const qualifiers off of the FromCl type... -template<typename FromCl> -struct isa_impl_cl<const FromCl> { - template<class ToCl> - static bool isa(const FromCl &Val) { - return isa_impl_cl<FromCl>::template isa<ToCl>(Val); - } -}; - -// Define pointer traits in terms of base traits... -template<class FromCl> -struct isa_impl_cl<FromCl*> { - template<class ToCl> - static bool isa(FromCl *Val) { - return isa_impl_cl<FromCl>::template isa<ToCl>(*Val); - } -}; - -// Define reference traits in terms of base traits... -template<class FromCl> -struct isa_impl_cl<FromCl&> { - template<class ToCl> - static bool isa(FromCl &Val) { - return isa_impl_cl<FromCl>::template isa<ToCl>(&Val); - } -}; - -template <class X, class Y> -inline bool isa(const Y &Val) { - return isa_impl_cl<Y>::template isa<X>(Val); -} - -//===----------------------------------------------------------------------===// -// cast<x> Support Templates -//===----------------------------------------------------------------------===// - -template<class To, class From> struct cast_retty; - - -// Calculate what type the 'cast' function should return, based on a requested -// type of To and a source type of From. -template<class To, class From> struct cast_retty_impl { - typedef To& ret_type; // Normal case, return Ty& -}; -template<class To, class From> struct cast_retty_impl<To, const From> { - typedef const To &ret_type; // Normal case, return Ty& -}; - -template<class To, class From> struct cast_retty_impl<To, From*> { - typedef To* ret_type; // Pointer arg case, return Ty* -}; - -template<class To, class From> struct cast_retty_impl<To, const From*> { - typedef const To* ret_type; // Constant pointer arg case, return const Ty* -}; - -template<class To, class From> struct cast_retty_impl<To, const From*const> { - typedef const To* ret_type; // Constant pointer arg case, return const Ty* -}; - - -template<class To, class From, class SimpleFrom> -struct cast_retty_wrap { - // When the simplified type and the from type are not the same, use the type - // simplifier to reduce the type, then reuse cast_retty_impl to get the - // resultant type. - typedef typename cast_retty<To, SimpleFrom>::ret_type ret_type; -}; - -template<class To, class FromTy> -struct cast_retty_wrap<To, FromTy, FromTy> { - // When the simplified type is equal to the from type, use it directly. - typedef typename cast_retty_impl<To,FromTy>::ret_type ret_type; -}; - -template<class To, class From> -struct cast_retty { - typedef typename cast_retty_wrap<To, From, - typename simplify_type<From>::SimpleType>::ret_type ret_type; -}; - -// Ensure the non-simple values are converted using the simplify_type template -// that may be specialized by smart pointers... -// -template<class To, class From, class SimpleFrom> struct cast_convert_val { - // This is not a simple type, use the template to simplify it... - static typename cast_retty<To, From>::ret_type doit(const From &Val) { - return cast_convert_val<To, SimpleFrom, - typename simplify_type<SimpleFrom>::SimpleType>::doit( - simplify_type<From>::getSimplifiedValue(Val)); - } -}; - -template<class To, class FromTy> struct cast_convert_val<To,FromTy,FromTy> { - // This _is_ a simple type, just cast it. - static typename cast_retty<To, FromTy>::ret_type doit(const FromTy &Val) { - return reinterpret_cast<typename cast_retty<To, FromTy>::ret_type>( - const_cast<FromTy&>(Val)); - } -}; - - - -// cast<X> - Return the argument parameter cast to the specified type. This -// casting operator asserts that the type is correct, so it does not return null -// on failure. But it will correctly return NULL when the input is NULL. -// Used Like this: -// -// cast<Instruction>(myVal)->getParent() -// -template <class X, class Y> -inline typename cast_retty<X, Y>::ret_type cast(const Y &Val) { - assert(isa<X>(Val) && "cast<Ty>() argument of incompatible type!"); - return cast_convert_val<X, Y, - typename simplify_type<Y>::SimpleType>::doit(Val); -} - -// cast_or_null<X> - Functionally identical to cast, except that a null value is -// accepted. -// -template <class X, class Y> -inline typename cast_retty<X, Y*>::ret_type cast_or_null(Y *Val) { - if (Val == 0) return 0; - assert(isa<X>(Val) && "cast_or_null<Ty>() argument of incompatible type!"); - return cast<X>(Val); -} - - -// dyn_cast<X> - Return the argument parameter cast to the specified type. This -// casting operator returns null if the argument is of the wrong type, so it can -// be used to test for a type as well as cast if successful. This should be -// used in the context of an if statement like this: -// -// if (const Instruction *I = dyn_cast<Instruction>(myVal)) { ... } -// - -template <class X, class Y> -inline typename cast_retty<X, Y>::ret_type dyn_cast(Y Val) { - return isa<X>(Val) ? cast<X, Y>(Val) : 0; -} - -// dyn_cast_or_null<X> - Functionally identical to dyn_cast, except that a null -// value is accepted. -// -template <class X, class Y> -inline typename cast_retty<X, Y>::ret_type dyn_cast_or_null(Y Val) { - return (Val && isa<X>(Val)) ? cast<X, Y>(Val) : 0; -} - - -#ifdef DEBUG_CAST_OPERATORS -#include <iostream> - -struct bar { - bar() {} -private: - bar(const bar &); -}; -struct foo { - void ext() const; - /* static bool classof(const bar *X) { - cerr << "Classof: " << X << "\n"; - return true; - }*/ -}; - -template <> inline bool isa_impl<foo,bar>(const bar &Val) { - cerr << "Classof: " << &Val << "\n"; - return true; -} - - -bar *fub(); -void test(bar &B1, const bar *B2) { - // test various configurations of const - const bar &B3 = B1; - const bar *const B4 = B2; - - // test isa - if (!isa<foo>(B1)) return; - if (!isa<foo>(B2)) return; - if (!isa<foo>(B3)) return; - if (!isa<foo>(B4)) return; - - // test cast - foo &F1 = cast<foo>(B1); - const foo *F3 = cast<foo>(B2); - const foo *F4 = cast<foo>(B2); - const foo &F8 = cast<foo>(B3); - const foo *F9 = cast<foo>(B4); - foo *F10 = cast<foo>(fub()); - - // test cast_or_null - const foo *F11 = cast_or_null<foo>(B2); - const foo *F12 = cast_or_null<foo>(B2); - const foo *F13 = cast_or_null<foo>(B4); - const foo *F14 = cast_or_null<foo>(fub()); // Shouldn't print. - - // These lines are errors... - //foo *F20 = cast<foo>(B2); // Yields const foo* - //foo &F21 = cast<foo>(B3); // Yields const foo& - //foo *F22 = cast<foo>(B4); // Yields const foo* - //foo &F23 = cast_or_null<foo>(B1); - //const foo &F24 = cast_or_null<foo>(B3); -} - -bar *fub() { return 0; } -void main() { - bar B; - test(B, &B); -} - -#endif - -} // End llvm namespace - -#endif |