/*
- * Copyright 2016 Facebook, Inc.
+ * Copyright 2017 Facebook, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* limitations under the License.
*/
-#ifndef FOLLY_PORTABILITY_H_
-#define FOLLY_PORTABILITY_H_
+#pragma once
#include <string.h>
#include <cstddef>
+#include <type_traits>
#include <folly/portability/Config.h>
#include <folly/CPortability.h>
-#ifdef __APPLE__
-# include <malloc/malloc.h>
-#endif
-
-#if FOLLY_HAVE_SCHED_H
- #include <sched.h>
-#endif
-
// Unaligned loads and stores
namespace folly {
#if FOLLY_HAVE_UNALIGNED_ACCESS
#else
constexpr bool kHasUnalignedAccess = false;
#endif
-}
+
+namespace portability_detail {
+
+template <typename I, I A, I B>
+using integral_max = std::integral_constant<I, (A < B) ? B : A>;
+
+template <typename I, I A, I... Bs>
+struct integral_sequence_max
+ : integral_max<I, A, integral_sequence_max<I, Bs...>::value> {};
+
+template <typename I, I A>
+struct integral_sequence_max<I, A> : std::integral_constant<I, A> {};
+
+template <typename... Ts>
+using max_alignment = integral_sequence_max<size_t, alignof(Ts)...>;
+
+using max_basic_alignment = max_alignment<
+ std::max_align_t,
+ long double,
+ double,
+ float,
+ long long int,
+ long int,
+ int,
+ short int,
+ bool,
+ char,
+ char16_t,
+ char32_t,
+ wchar_t,
+ std::nullptr_t>;
+} // namespace portability_detail
+
+constexpr size_t max_align_v = portability_detail::max_basic_alignment::value;
+
+// max_align_t is a type which is aligned at least as strictly as the
+// most-aligned basic type (see the specification of std::max_align_t). This
+// implementation exists because 32-bit iOS platforms have a broken
+// std::max_align_t (see below).
+//
+// You should refer to this as `::folly::max_align_t` in portable code, even if
+// you have `using namespace folly;` because C11 defines a global namespace
+// `max_align_t` type.
+//
+// To be certain, we consider every non-void fundamental type specified by the
+// standard. On most platforms `long double` would be enough, but iOS 32-bit
+// has an 8-byte aligned `double` and `long long int` and a 4-byte aligned
+// `long double`.
+//
+// So far we've covered locals and other non-allocated storage, but we also need
+// confidence that allocated storage from `malloc`, `new`, etc will also be
+// suitable for objects with this alignment reuirement.
+//
+// Apple document that their implementation of malloc will issue 16-byte
+// granularity chunks for small allocations (large allocations are page-size
+// granularity and page-aligned). We think that allocated storage will be
+// suitable for these objects based on the following assumptions:
+//
+// 1. 16-byte granularity also means 16-byte aligned.
+// 2. `new` and other allocators follow the `malloc` rules.
+//
+// We also have some anecdotal evidence: we don't see lots of misaligned-storage
+// crashes on 32-bit iOS apps that use `double`.
+//
+// Apple's allocation reference: http://bit.ly/malloc-small
+struct alignas(max_align_v) max_align_t {};
+
+} // namespace folly
// compiler specific attribute translation
// msvc should come first, so if clang is in msvc mode it gets the right defines
#else
# error Cannot define FOLLY_ALIGNED on this platform
#endif
-#define FOLLY_ALIGNED_MAX FOLLY_ALIGNED(alignof(std::max_align_t))
+#define FOLLY_ALIGNED_MAX FOLLY_ALIGNED(::folly::max_align_v)
// NOTE: this will only do checking in msvc with versions that support /analyze
#if _MSC_VER
# endif
/* nolint */
# define _USE_ATTRIBUTES_FOR_SAL 1
-# include <sal.h>
+# include <sal.h> // @manual
# define FOLLY_PRINTF_FORMAT _Printf_format_string_
# define FOLLY_PRINTF_FORMAT_ATTR(format_param, dots_param) /**/
#else
# define FOLLY_DEPRECATED(msg)
#endif
-// noreturn
-#if defined(_MSC_VER)
-# define FOLLY_NORETURN __declspec(noreturn)
-#elif defined(__clang__) || defined(__GNUC__)
-# define FOLLY_NORETURN __attribute__((__noreturn__))
-#else
-# define FOLLY_NORETURN
+// warn unused result
+#if defined(__has_cpp_attribute)
+#if __has_cpp_attribute(nodiscard)
+#define FOLLY_NODISCARD [[nodiscard]]
#endif
-
-// noinline
-#ifdef _MSC_VER
-# define FOLLY_NOINLINE __declspec(noinline)
+#endif
+#if !defined FOLLY_NODISCARD
+#if defined(_MSC_VER) && (_MSC_VER >= 1700)
+#define FOLLY_NODISCARD _Check_return_
#elif defined(__clang__) || defined(__GNUC__)
-# define FOLLY_NOINLINE __attribute__((__noinline__))
+#define FOLLY_NODISCARD __attribute__((__warn_unused_result__))
#else
-# define FOLLY_NOINLINE
+#define FOLLY_NODISCARD
+#endif
#endif
-// always inline
+// target
#ifdef _MSC_VER
-# define FOLLY_ALWAYS_INLINE __forceinline
-#elif defined(__clang__) || defined(__GNUC__)
-# define FOLLY_ALWAYS_INLINE inline __attribute__((__always_inline__))
+# define FOLLY_TARGET_ATTRIBUTE(target)
#else
-# define FOLLY_ALWAYS_INLINE inline
+# define FOLLY_TARGET_ATTRIBUTE(target) __attribute__((__target__(target)))
#endif
// detection for 64 bit
#endif
#if defined(__aarch64__)
-# define FOLLY_A64 1
+# define FOLLY_AARCH64 1
#else
-# define FOLLY_A64 0
+# define FOLLY_AARCH64 0
#endif
#if defined (__powerpc64__)
# define FOLLY_PPC64 0
#endif
+namespace folly {
+constexpr bool kIsArchAmd64 = FOLLY_X64 == 1;
+constexpr bool kIsArchAArch64 = FOLLY_AARCH64 == 1;
+constexpr bool kIsArchPPC64 = FOLLY_PPC64 == 1;
+} // namespace folly
+
+namespace folly {
+
+#if FOLLY_SANITIZE_ADDRESS
+constexpr bool kIsSanitizeAddress = true;
+#else
+constexpr bool kIsSanitizeAddress = false;
+#endif
+
+#if FOLLY_SANITIZE_THREAD
+constexpr bool kIsSanitizeThread = true;
+#else
+constexpr bool kIsSanitizeThread = false;
+#endif
+
+#if FOLLY_SANITIZE
+constexpr bool kIsSanitize = true;
+#else
+constexpr bool kIsSanitize = false;
+#endif
+} // namespace folly
+
// packing is very ugly in msvc
#ifdef _MSC_VER
# define FOLLY_PACK_ATTR /**/
#elif defined(__clang__) || defined(__GNUC__)
# define FOLLY_PUSH_WARNING _Pragma("GCC diagnostic push")
# define FOLLY_POP_WARNING _Pragma("GCC diagnostic pop")
-#define FOLLY_GCC_DISABLE_WARNING_INTERNAL3(warningName) #warningName
-#define FOLLY_GCC_DISABLE_WARNING_INTERNAL2(warningName) \
- FOLLY_GCC_DISABLE_WARNING_INTERNAL3(warningName)
-#define FOLLY_GCC_DISABLE_WARNING(warningName) \
- _Pragma(FOLLY_GCC_DISABLE_WARNING_INTERNAL2(GCC diagnostic ignored \
- FOLLY_GCC_DISABLE_WARNING_INTERNAL3(-W##warningName)))
+# define FOLLY_GCC_DISABLE_WARNING_INTERNAL2(warningName) #warningName
+# define FOLLY_GCC_DISABLE_WARNING(warningName) \
+ _Pragma( \
+ FOLLY_GCC_DISABLE_WARNING_INTERNAL2(GCC diagnostic ignored warningName))
// Disable the MSVC warnings.
# define FOLLY_MSVC_DISABLE_WARNING(warningNumber)
#else
# define FOLLY_MSVC_DISABLE_WARNING(warningNumber)
#endif
-// portable version check
-#ifndef __GNUC_PREREQ
-# if defined __GNUC__ && defined __GNUC_MINOR__
-/* nolint */
-# define __GNUC_PREREQ(maj, min) ((__GNUC__ << 16) + __GNUC_MINOR__ >= \
- ((maj) << 16) + (min))
-# else
-/* nolint */
-# define __GNUC_PREREQ(maj, min) 0
-# endif
-#endif
-
-#if defined(__GNUC__) && !defined(__APPLE__) && !__GNUC_PREREQ(4,9)
-// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56019
-// gcc 4.8.x incorrectly placed max_align_t in the root namespace
-// Alias it into std (where it's found in 4.9 and later)
-namespace std { typedef ::max_align_t max_align_t; }
-#endif
-
-// portable version check for clang
-#ifndef __CLANG_PREREQ
-# if defined __clang__ && defined __clang_major__ && defined __clang_minor__
-/* nolint */
-# define __CLANG_PREREQ(maj, min) \
- ((__clang_major__ << 16) + __clang_minor__ >= ((maj) << 16) + (min))
-# else
-/* nolint */
-# define __CLANG_PREREQ(maj, min) 0
-# endif
+#ifdef FOLLY_HAVE_SHADOW_LOCAL_WARNINGS
+#define FOLLY_GCC_DISABLE_NEW_SHADOW_WARNINGS \
+ FOLLY_GCC_DISABLE_WARNING("-Wshadow-compatible-local") \
+ FOLLY_GCC_DISABLE_WARNING("-Wshadow-local")
+#else
+#define FOLLY_GCC_DISABLE_NEW_SHADOW_WARNINGS /* empty */
#endif
/* Platform specific TLS support
# error cannot define platform specific thread local storage
#endif
-#if defined(__APPLE__) && (TARGET_IPHONE_SIMULATOR || TARGET_OS_IPHONE)
+#if FOLLY_MOBILE
#undef FOLLY_TLS
#endif
-// Define to 1 if you have the `preadv' and `pwritev' functions, respectively
-#if !defined(FOLLY_HAVE_PREADV) && !defined(FOLLY_HAVE_PWRITEV)
-# if defined(__GLIBC_PREREQ)
-# if __GLIBC_PREREQ(2, 10)
-# define FOLLY_HAVE_PREADV 1
-# define FOLLY_HAVE_PWRITEV 1
-# endif
-# endif
-#endif
-
// It turns out that GNU libstdc++ and LLVM libc++ differ on how they implement
// the 'std' namespace; the latter uses inline namespaces. Wrap this decision
// up in a macro to make forward-declarations easier.
#if FOLLY_USE_LIBCPP
-#include <__config>
+#include <__config> // @manual
#define FOLLY_NAMESPACE_STD_BEGIN _LIBCPP_BEGIN_NAMESPACE_STD
#define FOLLY_NAMESPACE_STD_END _LIBCPP_END_NAMESPACE_STD
#else
// If the new c++ ABI is used, __cxx11 inline namespace needs to be added to
// some types, e.g. std::list.
#if _GLIBCXX_USE_CXX11_ABI
-# define FOLLY_GLIBCXX_NAMESPACE_CXX11_BEGIN _GLIBCXX_BEGIN_NAMESPACE_CXX11
+#define FOLLY_GLIBCXX_NAMESPACE_CXX11_BEGIN \
+ inline _GLIBCXX_BEGIN_NAMESPACE_CXX11
# define FOLLY_GLIBCXX_NAMESPACE_CXX11_END _GLIBCXX_END_NAMESPACE_CXX11
#else
# define FOLLY_GLIBCXX_NAMESPACE_CXX11_BEGIN
# define FOLLY_GLIBCXX_NAMESPACE_CXX11_END
#endif
-// Some platforms lack clock_gettime(2) and clock_getres(2). Inject our own
-// versions of these into the global namespace.
-#if FOLLY_HAVE_CLOCK_GETTIME
-#include <time.h>
-#else
-#include <folly/detail/Clock.h>
-#endif
-
-// Provide our own std::__throw_* wrappers for platforms that don't have them
-#if FOLLY_HAVE_BITS_FUNCTEXCEPT_H
-#include <bits/functexcept.h>
-#else
-#include <folly/detail/FunctionalExcept.h>
-#endif
-
-#if defined(__cplusplus)
-// Unfortunately, boost::has_trivial_copy<T> is broken in libc++ due to its
-// usage of __has_trivial_copy(), so we can't use it as a
-// least-common-denominator for C++11 implementations that don't support
-// std::is_trivially_copyable<T>.
-//
-// http://stackoverflow.com/questions/12754886/has-trivial-copy-behaves-differently-in-clang-and-gcc-whos-right
-//
-// As a result, use std::is_trivially_copyable() where it exists, and fall back
-// to Boost otherwise.
-#if FOLLY_HAVE_STD__IS_TRIVIALLY_COPYABLE
-#include <type_traits>
-#define FOLLY_IS_TRIVIALLY_COPYABLE(T) \
- (std::is_trivially_copyable<T>::value)
-#else
-#include <boost/type_traits.hpp>
-#define FOLLY_IS_TRIVIALLY_COPYABLE(T) \
- (boost::has_trivial_copy<T>::value && \
- boost::has_trivial_destructor<T>::value)
-#endif
-#endif // __cplusplus
-
// MSVC specific defines
// mainly for posix compat
#ifdef _MSC_VER
#include <folly/portability/SysTypes.h>
-// sprintf semantics are not exactly identical
-// but current usage is not a problem
-# define snprintf _snprintf
-
-// semantics here are identical
-# define strerror_r(errno,buf,len) strerror_s(buf,len,errno)
-
// compiler specific to compiler specific
// nolint
# define __PRETTY_FUNCTION__ __FUNCSIG__
// Hide a GCC specific thing that breaks MSVC if left alone.
# define __extension__
-#ifdef _M_IX86_FP
-# define FOLLY_SSE _M_IX86_FP
-# define FOLLY_SSE_MINOR 0
-#endif
+// We have compiler support for the newest of the new, but
+// MSVC doesn't tell us that.
+#define __SSE4_2__ 1
#endif
#else
constexpr auto kIsDebug = true;
#endif
-}
+} // namespace folly
// Endianness
namespace folly {
constexpr auto kIsLittleEndian = __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__;
#endif
constexpr auto kIsBigEndian = !kIsLittleEndian;
-}
+} // namespace folly
#ifndef FOLLY_SSE
# if defined(__SSE4_2__)
namespace FOLLY_GFLAGS_NAMESPACE { }
namespace gflags {
using namespace FOLLY_GFLAGS_NAMESPACE;
-} // namespace gflags
+} // namespace gflags
#endif
// for TARGET_OS_IPHONE
#ifdef __APPLE__
-#include <TargetConditionals.h>
-#endif
-
-// MacOS doesn't have malloc_usable_size()
-#if defined(__APPLE__) && !defined(FOLLY_HAVE_MALLOC_USABLE_SIZE)
-inline size_t malloc_usable_size(void* ptr) {
- return malloc_size(ptr);
-}
+#include <TargetConditionals.h> // @manual
#endif
// RTTI may not be enabled for this compilation unit.
# define FOLLY_HAS_RTTI 1
#endif
-#ifdef _MSC_VER
-# include <intrin.h>
+#if defined(__APPLE__) || defined(_MSC_VER)
+#define FOLLY_STATIC_CTOR_PRIORITY_MAX
+#else
+// 101 is the highest priority allowed by the init_priority attribute.
+// This priority is already used by JEMalloc and other memory allocators so
+// we will take the next one.
+#define FOLLY_STATIC_CTOR_PRIORITY_MAX __attribute__((__init_priority__(102)))
#endif
namespace folly {
-inline void asm_volatile_memory() {
-#if defined(__clang__) || defined(__GNUC__)
- asm volatile("" : : : "memory");
-#elif defined(_MSC_VER)
- ::_ReadWriteBarrier();
-#endif
-}
-
-inline void asm_volatile_pause() {
-#if defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_X64))
- ::_mm_pause();
-#elif defined(__i386__) || FOLLY_X64
- asm volatile ("pause");
-#elif FOLLY_A64 || defined(__arm__)
- asm volatile ("yield");
-#elif FOLLY_PPC64
- asm volatile("or 27,27,27");
-#endif
-}
-inline void asm_pause() {
-#if defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_X64))
- ::_mm_pause();
-#elif defined(__i386__) || FOLLY_X64
- asm ("pause");
-#elif FOLLY_A64 || defined(__arm__)
- asm ("yield");
-#elif FOLLY_PPC64
- asm ("or 31,31,31");
-#endif
-}
+#if __OBJC__
+constexpr auto kIsObjC = true;
+#else
+constexpr auto kIsObjC = false;
+#endif
-#if defined(__APPLE__) || defined(_MSC_VER)
-#define MAX_STATIC_CONSTRUCTOR_PRIORITY
+#if defined(__linux__) && !FOLLY_MOBILE
+constexpr auto kIsLinux = true;
#else
-// 101 is the highest priority allowed by the init_priority attribute.
-// This priority is already used by JEMalloc and other memory allocators so
-// we will take the next one.
-#define MAX_STATIC_CONSTRUCTOR_PRIORITY __attribute__ ((__init_priority__(102)))
+constexpr auto kIsLinux = false;
#endif
+#if defined(_WIN32)
+constexpr auto kIsWindows = true;
+constexpr auto kMscVer = _MSC_VER;
+#else
+constexpr auto kIsWindows = false;
+constexpr auto kMscVer = 0;
+#endif
} // namespace folly
-#endif // FOLLY_PORTABILITY_H_
+
+// Define FOLLY_USE_CPP14_CONSTEXPR to be true if the compiler's C++14
+// constexpr support is "good enough".
+#ifndef FOLLY_USE_CPP14_CONSTEXPR
+#if defined(__clang__)
+#define FOLLY_USE_CPP14_CONSTEXPR __cplusplus >= 201300L
+#elif defined(__GNUC__)
+#define FOLLY_USE_CPP14_CONSTEXPR __cplusplus >= 201304L
+#else
+#define FOLLY_USE_CPP14_CONSTEXPR 0 // MSVC?
+#endif
+#endif
+
+#if FOLLY_USE_CPP14_CONSTEXPR
+#define FOLLY_CPP14_CONSTEXPR constexpr
+#else
+#define FOLLY_CPP14_CONSTEXPR inline
+#endif
+
+#if __cpp_coroutines >= 201703L || (_MSC_VER && _RESUMABLE_FUNCTIONS_SUPPORTED)
+#define FOLLY_HAS_COROUTINES 1
+#endif
+
+// MSVC 2017.5
+#if __cpp_noexcept_function_type >= 201510 || _MSC_FULL_VER >= 191225816
+#define FOLLY_HAVE_NOEXCEPT_FUNCTION_TYPE 1
+#endif
projects / folly.git / blobdiff