diff options
-rw-r--r-- | llvm/include/llvm/Support/Casting.h | 70 | ||||
-rw-r--r-- | llvm/unittests/Support/Casting.cpp | 75 |
2 files changed, 145 insertions, 0 deletions
diff --git a/llvm/include/llvm/Support/Casting.h b/llvm/include/llvm/Support/Casting.h index a73047b2b55..3a0c5536c01 100644 --- a/llvm/include/llvm/Support/Casting.h +++ b/llvm/include/llvm/Support/Casting.h @@ -18,6 +18,7 @@ #include "llvm/Support/Compiler.h" #include "llvm/Support/type_traits.h" #include <cassert> +#include <memory> namespace llvm { @@ -76,6 +77,14 @@ template <typename To, typename From> struct isa_impl_cl<To, const From> { } }; +template <typename To, typename From> +struct isa_impl_cl<To, const std::unique_ptr<From>> { + static inline bool doit(const std::unique_ptr<From> &Val) { + assert(Val && "isa<> used on a null pointer"); + return isa_impl_cl<To, From>::doit(*Val); + } +}; + template <typename To, typename From> struct isa_impl_cl<To, From*> { static inline bool doit(const From *Val) { assert(Val && "isa<> used on a null pointer"); @@ -161,6 +170,15 @@ 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> +struct cast_retty_impl<To, std::unique_ptr<From>> { +private: + typedef typename cast_retty_impl<To, From *>::ret_type PointerType; + typedef typename std::remove_pointer<PointerType>::type ResultType; + +public: + typedef std::unique_ptr<ResultType> ret_type; +}; template<class To, class From, class SimpleFrom> struct cast_retty_wrap { @@ -238,6 +256,16 @@ inline typename cast_retty<X, Y *>::ret_type cast(Y *Val) { typename simplify_type<Y*>::SimpleType>::doit(Val); } +template <class X, class Y> +inline typename cast_retty<X, std::unique_ptr<Y>>::ret_type +cast(std::unique_ptr<Y> &&Val) { + assert(isa<X>(Val.get()) && "cast<Ty>() argument of incompatible type!"); + using ret_type = typename cast_retty<X, std::unique_ptr<Y>>::ret_type; + return ret_type( + cast_convert_val<X, Y *, typename simplify_type<Y *>::SimpleType>::doit( + Val.release())); +} + // cast_or_null<X> - Functionally identical to cast, except that a null value is // accepted. // @@ -271,6 +299,13 @@ cast_or_null(Y *Val) { return cast<X>(Val); } +template <class X, class Y> +inline typename cast_retty<X, std::unique_ptr<Y>>::ret_type +cast_or_null(std::unique_ptr<Y> &&Val) { + if (!Val) + return nullptr; + return cast<X>(std::move(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 @@ -323,6 +358,41 @@ dyn_cast_or_null(Y *Val) { return (Val && isa<X>(Val)) ? cast<X>(Val) : nullptr; } +// unique_dyn_cast<X> - Given a unique_ptr<Y>, try to return a unique_ptr<X>, +// taking ownership of the input pointer iff isa<X>(Val) is true. If the +// cast is successful, From refers to nullptr on exit and the casted value +// is returned. If the cast is unsuccessful, the function returns nullptr +// and From is unchanged. +template <class X, class Y> +LLVM_NODISCARD inline auto unique_dyn_cast(std::unique_ptr<Y> &Val) + -> decltype(cast<X>(Val)) { + if (!isa<X>(Val)) + return nullptr; + return cast<X>(std::move(Val)); +} + +template <class X, class Y> +LLVM_NODISCARD inline auto unique_dyn_cast(std::unique_ptr<Y> &&Val) + -> decltype(cast<X>(Val)) { + return unique_dyn_cast<X, Y>(Val); +} + +// dyn_cast_or_null<X> - Functionally identical to unique_dyn_cast, except that +// a null value is accepted. +template <class X, class Y> +LLVM_NODISCARD inline auto unique_dyn_cast_or_null(std::unique_ptr<Y> &Val) + -> decltype(cast<X>(Val)) { + if (!Val) + return nullptr; + return unique_dyn_cast(Val); +} + +template <class X, class Y> +LLVM_NODISCARD inline auto unique_dyn_cast_or_null(std::unique_ptr<Y> &&Val) + -> decltype(cast<X>(Val)) { + return unique_dyn_cast_or_null<X, Y>(Val); +} + } // End llvm namespace #endif diff --git a/llvm/unittests/Support/Casting.cpp b/llvm/unittests/Support/Casting.cpp index e6c35fc21eb..9a818f6bdeb 100644 --- a/llvm/unittests/Support/Casting.cpp +++ b/llvm/unittests/Support/Casting.cpp @@ -40,6 +40,14 @@ struct foo { }*/ }; +struct base { + virtual ~base() {} +}; + +struct derived : public base { + static bool classof(const base *B) { return true; } +}; + template <> struct isa_impl<foo, bar> { static inline bool doit(const bar &Val) { dbgs() << "Classof: " << &Val << "\n"; @@ -47,6 +55,10 @@ template <> struct isa_impl<foo, bar> { } }; +template <typename T> struct isa_impl<foo, T> { + static inline bool doit(const T &Val) { return false; } +}; + foo *bar::baz() { return cast<foo>(this); } @@ -123,6 +135,13 @@ TEST(CastingTest, cast) { // EXPECT_EQ(F7, null_foo); foo *F8 = B1.baz(); EXPECT_NE(F8, null_foo); + + std::unique_ptr<const bar> BP(B2); + auto FP = cast<foo>(std::move(BP)); + static_assert(std::is_same<std::unique_ptr<const foo>, decltype(FP)>::value, + "Incorrect deduced return type!"); + EXPECT_NE(FP.get(), null_foo); + FP.release(); } TEST(CastingTest, cast_or_null) { @@ -136,6 +155,10 @@ TEST(CastingTest, cast_or_null) { EXPECT_EQ(F14, null_foo); foo *F15 = B1.caz(); EXPECT_NE(F15, null_foo); + + std::unique_ptr<const bar> BP(fub()); + auto FP = cast_or_null<foo>(std::move(BP)); + EXPECT_EQ(FP.get(), null_foo); } TEST(CastingTest, dyn_cast) { @@ -165,6 +188,58 @@ TEST(CastingTest, dyn_cast_or_null) { EXPECT_NE(F5, null_foo); } +std::unique_ptr<derived> newd() { return llvm::make_unique<derived>(); } +std::unique_ptr<base> newb() { return llvm::make_unique<derived>(); } + +TEST(CastingTest, unique_dyn_cast) { + derived *OrigD = nullptr; + auto D = llvm::make_unique<derived>(); + OrigD = D.get(); + + // Converting from D to itself is valid, it should return a new unique_ptr + // and the old one should become nullptr. + auto NewD = unique_dyn_cast<derived>(D); + ASSERT_EQ(OrigD, NewD.get()); + ASSERT_EQ(nullptr, D); + + // Converting from D to B is valid, B should have a value and D should be + // nullptr. + auto B = unique_dyn_cast<base>(NewD); + ASSERT_EQ(OrigD, B.get()); + ASSERT_EQ(nullptr, NewD); + + // Converting from B to itself is valid, it should return a new unique_ptr + // and the old one should become nullptr. + auto NewB = unique_dyn_cast<base>(B); + ASSERT_EQ(OrigD, NewB.get()); + ASSERT_EQ(nullptr, B); + + // Converting from B to D is valid, D should have a value and B should be + // nullptr; + D = unique_dyn_cast<derived>(NewB); + ASSERT_EQ(OrigD, D.get()); + ASSERT_EQ(nullptr, NewB); + + // Converting between unrelated types should fail. The original value should + // remain unchanged and it should return nullptr. + auto F = unique_dyn_cast<foo>(D); + ASSERT_EQ(nullptr, F); + ASSERT_EQ(OrigD, D.get()); + + // All of the above should also hold for temporaries. + auto D2 = unique_dyn_cast<derived>(newd()); + EXPECT_NE(nullptr, D2); + + auto B2 = unique_dyn_cast<derived>(newb()); + EXPECT_NE(nullptr, B2); + + auto B3 = unique_dyn_cast<base>(newb()); + EXPECT_NE(nullptr, B3); + + auto F2 = unique_dyn_cast<foo>(newb()); + EXPECT_EQ(nullptr, F2); +} + // These lines are errors... //foo *F20 = cast<foo>(B2); // Yields const foo* //foo &F21 = cast<foo>(B3); // Yields const foo& |