From 142e56d1574d92985bb2b2c9b3ac77e70302ad7f Mon Sep 17 00:00:00 2001 From: Jordan Rose Date: Fri, 30 Nov 2012 00:38:53 +0000 Subject: [PATCH] Add a new C++11 compatibility macro, LLVM_LVALUE_FUNCTION. This expands to '&', and is intended to be used when an /optional/ rvalue override is available. Before: void foo() const { ... } After: void foo() const LLVM_LVALUE_FUNCTION { ... } void foo() && { ... } This is used to allow moving the contents of an Optional. llvm-svn: 168963 --- llvm/include/llvm/ADT/Optional.h | 9 +++++++-- llvm/include/llvm/Support/Compiler.h | 10 ++++++++++ 2 files changed, 17 insertions(+), 2 deletions(-) diff --git a/llvm/include/llvm/ADT/Optional.h b/llvm/include/llvm/ADT/Optional.h index f43aeb1..23100ab 100644 --- a/llvm/include/llvm/ADT/Optional.h +++ b/llvm/include/llvm/ADT/Optional.h @@ -48,12 +48,17 @@ public: } const T* getPointer() const { assert(hasVal); return &x; } - const T& getValue() const { assert(hasVal); return x; } + const T& getValue() const LLVM_LVALUE_FUNCTION { assert(hasVal); return x; } operator bool() const { return hasVal; } bool hasValue() const { return hasVal; } const T* operator->() const { return getPointer(); } - const T& operator*() const { assert(hasVal); return x; } + const T& operator*() const LLVM_LVALUE_FUNCTION { assert(hasVal); return x; } + +#if LLVM_USE_RVALUE_REFERENCES + T&& getValue() && { assert(hasVal); return std::move(x); } + T&& operator*() && { assert(hasVal); return std::move(x); } +#endif }; template struct simplify_type; diff --git a/llvm/include/llvm/Support/Compiler.h b/llvm/include/llvm/Support/Compiler.h index 5acc716..7d9785c 100644 --- a/llvm/include/llvm/Support/Compiler.h +++ b/llvm/include/llvm/Support/Compiler.h @@ -38,6 +38,16 @@ #define llvm_move(value) (value) #endif +/// Expands to '&' if r-value references are supported. +/// +/// This can be used to provide l-value/r-value overrides of member functions. +/// The r-value override should be guarded by LLVM_USE_RVALUE_REFERENCES +#if LLVM_USE_RVALUE_REFERENCES +#define LLVM_LVALUE_FUNCTION & +#else +#define LLVM_LVALUE_FUNCTION +#endif + /// LLVM_DELETED_FUNCTION - Expands to = delete if the compiler supports it. /// Use to mark functions as uncallable. Member functions with this should /// be declared private so that some behavior is kept in C++03 mode. -- 2.7.4