#ifndef LLVM_SUPPORT_COMPILER_H
#define LLVM_SUPPORT_COMPILER_H
+#ifndef __has_feature
+# define __has_feature(x) 0
+#endif
+
+/// \brief Does the compiler support r-value references?
+/// This implies that <utility> provides the one-argument std::move; it
+/// does not imply the existence of any other C++ library features.
+#if (__has_feature(cxx_rvalue_references) \
+ || defined(__GXX_EXPERIMENTAL_CXX0X__) \
+ || (defined(_MSC_VER) && _MSC_VER >= 1600))
+#define LLVM_HAS_RVALUE_REFERENCES 1
+#else
+#define LLVM_HAS_RVALUE_REFERENCES 0
+#endif
+
+/// \brief Does the compiler support r-value reference *this?
+///
+/// Sadly, this is separate from just r-value reference support because GCC
+/// implemented everything but this thus far. No release of GCC yet has support
+/// for this feature so it is enabled with Clang only.
+/// FIXME: This should change to a version check when GCC grows support for it.
+#if __has_feature(cxx_rvalue_references)
+#define LLVM_HAS_RVALUE_REFERENCE_THIS 1
+#else
+#define LLVM_HAS_RVALUE_REFERENCE_THIS 0
+#endif
+
+/// llvm_move - Expands to ::std::move if the compiler supports
+/// r-value references; otherwise, expands to the argument.
+#if LLVM_HAS_RVALUE_REFERENCES
+#define llvm_move(value) (::std::move(value))
+#else
+#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_HAS_RVALUE_REFERENCE_THIS
+#if LLVM_HAS_RVALUE_REFERENCE_THIS
+#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.
+///
+/// class DontCopy {
+/// private:
+/// DontCopy(const DontCopy&) LLVM_DELETED_FUNCTION;
+/// DontCopy &operator =(const DontCopy&) LLVM_DELETED_FUNCTION;
+/// public:
+/// ...
+/// };
+#if (__has_feature(cxx_deleted_functions) \
+ || defined(__GXX_EXPERIMENTAL_CXX0X__))
+ // No version of MSVC currently supports this.
+#define LLVM_DELETED_FUNCTION = delete
+#else
+#define LLVM_DELETED_FUNCTION
+#endif
+
+/// LLVM_FINAL - Expands to 'final' if the compiler supports it.
+/// Use to mark classes or virtual methods as final.
+#if (__has_feature(cxx_override_control))
+#define LLVM_FINAL final
+#else
+#define LLVM_FINAL
+#endif
+
+/// LLVM_OVERRIDE - Expands to 'override' if the compiler supports it.
+/// Use to mark virtual methods as overriding a base class method.
+#if (__has_feature(cxx_override_control))
+#define LLVM_OVERRIDE override
+#else
+#define LLVM_OVERRIDE
+#endif
+
/// LLVM_LIBRARY_VISIBILITY - If a class marked with this attribute is linked
/// into a shared library, then the class should be private to the library and
/// not accessible from outside it. Can also be used to mark variables and
/// functions, making them private to any shared library they are linked into.
-
-/// LLVM_GLOBAL_VISIBILITY - If a class marked with this attribute is linked
-/// into a shared library, then the class will be accessible from outside the
-/// the library. Can also be used to mark variables and functions, making them
-/// accessible from outside any shared library they are linked into.
-#if defined(__MINGW32__) || defined(__CYGWIN__)
-#define LLVM_LIBRARY_VISIBILITY
-#define LLVM_GLOBAL_VISIBILITY __declspec(dllexport)
-#elif (__GNUC__ >= 4)
+#if (__GNUC__ >= 4) && !defined(__MINGW32__) && !defined(__CYGWIN__)
#define LLVM_LIBRARY_VISIBILITY __attribute__ ((visibility("hidden")))
-#define LLVM_GLOBAL_VISIBILITY __attribute__ ((visibility("default")))
#else
#define LLVM_LIBRARY_VISIBILITY
-#define LLVM_GLOBAL_VISIBILITY
#endif
#if (__GNUC__ >= 4 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1))
-#define ATTRIBUTE_USED __attribute__((__used__))
+#define LLVM_ATTRIBUTE_USED __attribute__((__used__))
#else
-#define ATTRIBUTE_USED
+#define LLVM_ATTRIBUTE_USED
#endif
+// Some compilers warn about unused functions. When a function is sometimes
+// used or not depending on build settings (e.g. a function only called from
+// within "assert"), this attribute can be used to suppress such warnings.
+//
+// However, it shouldn't be used for unused *variables*, as those have a much
+// more portable solution:
+// (void)unused_var_name;
+// Prefer cast-to-void wherever it is sufficient.
#if (__GNUC__ >= 4 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1))
-#define ATTRIBUTE_UNUSED __attribute__((__unused__))
+#define LLVM_ATTRIBUTE_UNUSED __attribute__((__unused__))
+#else
+#define LLVM_ATTRIBUTE_UNUSED
+#endif
+
+#if (__GNUC__ >= 4) && !defined(__MINGW32__) && !defined(__CYGWIN__)
+#define LLVM_ATTRIBUTE_WEAK __attribute__((__weak__))
#else
-#define ATTRIBUTE_UNUSED
+#define LLVM_ATTRIBUTE_WEAK
#endif
-#ifdef __GNUC__ // aka 'ATTRIBUTE_CONST' but following LLVM Conventions.
-#define ATTRIBUTE_READNONE __attribute__((__const__))
+#ifdef __GNUC__ // aka 'CONST' but following LLVM Conventions.
+#define LLVM_READNONE __attribute__((__const__))
#else
-#define ATTRIBUTE_READNONE
+#define LLVM_READNONE
#endif
-#ifdef __GNUC__ // aka 'ATTRIBUTE_PURE' but following LLVM Conventions.
-#define ATTRIBUTE_READONLY __attribute__((__pure__))
+#ifdef __GNUC__ // aka 'PURE' but following LLVM Conventions.
+#define LLVM_READONLY __attribute__((__pure__))
#else
-#define ATTRIBUTE_READONLY
+#define LLVM_READONLY
#endif
#if (__GNUC__ >= 4)
-#define BUILTIN_EXPECT(EXPR, VALUE) __builtin_expect((EXPR), (VALUE))
+#define LLVM_LIKELY(EXPR) __builtin_expect((bool)(EXPR), true)
+#define LLVM_UNLIKELY(EXPR) __builtin_expect((bool)(EXPR), false)
#else
-#define BUILTIN_EXPECT(EXPR, VALUE) (EXPR)
+#define LLVM_LIKELY(EXPR) (EXPR)
+#define LLVM_UNLIKELY(EXPR) (EXPR)
#endif
// C++ doesn't support 'extern template' of template specializations. GCC does,
#define TEMPLATE_INSTANTIATION(X)
#endif
-// DISABLE_INLINE - On compilers where we have a directive to do so, mark a
-// method "not for inlining".
+/// LLVM_ATTRIBUTE_NOINLINE - On compilers where we have a directive to do so,
+/// mark a method "not for inlining".
#if (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4))
-#define DISABLE_INLINE __attribute__((noinline))
+#define LLVM_ATTRIBUTE_NOINLINE __attribute__((noinline))
#elif defined(_MSC_VER)
-#define DISABLE_INLINE __declspec(noinline)
+#define LLVM_ATTRIBUTE_NOINLINE __declspec(noinline)
#else
-#define DISABLE_INLINE
+#define LLVM_ATTRIBUTE_NOINLINE
#endif
-// ALWAYS_INLINE - On compilers where we have a directive to do so, mark a
-// method "always inline" because it is performance sensitive.
-// GCC 3.4 supported this but is buggy in various cases and produces
-// unimplemented errors, just use it in GCC 4.0 and later.
+/// LLVM_ATTRIBUTE_ALWAYS_INLINE - On compilers where we have a directive to do
+/// so, mark a method "always inline" because it is performance sensitive. GCC
+/// 3.4 supported this but is buggy in various cases and produces unimplemented
+/// errors, just use it in GCC 4.0 and later.
#if __GNUC__ > 3
-#define ALWAYS_INLINE __attribute__((always_inline))
+#define LLVM_ATTRIBUTE_ALWAYS_INLINE inline __attribute__((always_inline))
+#elif defined(_MSC_VER)
+#define LLVM_ATTRIBUTE_ALWAYS_INLINE __forceinline
#else
-// TODO: No idea how to do this with MSVC.
-#define ALWAYS_INLINE
+#define LLVM_ATTRIBUTE_ALWAYS_INLINE
#endif
+#ifdef __GNUC__
+#define LLVM_ATTRIBUTE_NORETURN __attribute__((noreturn))
+#elif defined(_MSC_VER)
+#define LLVM_ATTRIBUTE_NORETURN __declspec(noreturn)
+#else
+#define LLVM_ATTRIBUTE_NORETURN
+#endif
+/// LLVM_EXTENSION - Support compilers where we have a keyword to suppress
+/// pedantic diagnostics.
#ifdef __GNUC__
-#define NORETURN __attribute__((noreturn))
+#define LLVM_EXTENSION __extension__
+#else
+#define LLVM_EXTENSION
+#endif
+
+// LLVM_ATTRIBUTE_DEPRECATED(decl, "message")
+#if __has_feature(attribute_deprecated_with_message)
+# define LLVM_ATTRIBUTE_DEPRECATED(decl, message) \
+ decl __attribute__((deprecated(message)))
+#elif defined(__GNUC__)
+# define LLVM_ATTRIBUTE_DEPRECATED(decl, message) \
+ decl __attribute__((deprecated))
+#elif defined(_MSC_VER)
+# define LLVM_ATTRIBUTE_DEPRECATED(decl, message) \
+ __declspec(deprecated(message)) decl
+#else
+# define LLVM_ATTRIBUTE_DEPRECATED(decl, message) \
+ decl
+#endif
+
+/// LLVM_BUILTIN_UNREACHABLE - On compilers which support it, expands
+/// to an expression which states that it is undefined behavior for the
+/// compiler to reach this point. Otherwise is not defined.
+#if defined(__clang__) || (__GNUC__ > 4) \
+ || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)
+# define LLVM_BUILTIN_UNREACHABLE __builtin_unreachable()
#elif defined(_MSC_VER)
-#define NORETURN __declspec(noreturn)
+# define LLVM_BUILTIN_UNREACHABLE __assume(false)
+#endif
+
+/// LLVM_BUILTIN_TRAP - On compilers which support it, expands to an expression
+/// which causes the program to exit abnormally.
+#if defined(__clang__) || (__GNUC__ > 4) \
+ || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
+# define LLVM_BUILTIN_TRAP __builtin_trap()
+#else
+# define LLVM_BUILTIN_TRAP *(volatile int*)0x11 = 0
+#endif
+
+/// \macro LLVM_ASSUME_ALIGNED
+/// \brief Returns a pointer with an assumed alignment.
+#if !defined(__clang__) && ((__GNUC__ > 4) \
+ || (__GNUC__ == 4 && __GNUC_MINOR__ >= 7))
+// FIXME: Enable on clang when it supports it.
+# define LLVM_ASSUME_ALIGNED(p, a) __builtin_assume_aligned(p, a)
+#elif defined(LLVM_BUILTIN_UNREACHABLE)
+# define LLVM_ASSUME_ALIGNED(p, a) \
+ (((uintptr_t(p) % (a)) == 0) ? (p) : (LLVM_BUILTIN_UNREACHABLE, (p)))
#else
-#define NORETURN
+# define LLVM_ASSUME_ALIGNED(p, a) (p)
#endif
#endif