diff options
Diffstat (limited to 'absl/base/config.h')
| -rw-r--r-- | absl/base/config.h | 319 |
1 files changed, 245 insertions, 74 deletions
diff --git a/absl/base/config.h b/absl/base/config.h index 95449969..8533aead 100644 --- a/absl/base/config.h +++ b/absl/base/config.h @@ -56,6 +56,25 @@ #include <cstddef> #endif // __cplusplus +// ABSL_INTERNAL_CPLUSPLUS_LANG +// +// MSVC does not set the value of __cplusplus correctly, but instead uses +// _MSVC_LANG as a stand-in. +// https://docs.microsoft.com/en-us/cpp/preprocessor/predefined-macros +// +// However, there are reports that MSVC even sets _MSVC_LANG incorrectly at +// times, for example: +// https://github.com/microsoft/vscode-cpptools/issues/1770 +// https://reviews.llvm.org/D70996 +// +// For this reason, this symbol is considered INTERNAL and code outside of +// Abseil must not use it. +#if defined(_MSVC_LANG) +#define ABSL_INTERNAL_CPLUSPLUS_LANG _MSVC_LANG +#elif defined(__cplusplus) +#define ABSL_INTERNAL_CPLUSPLUS_LANG __cplusplus +#endif + #if defined(__APPLE__) // Included for TARGET_OS_IPHONE, __IPHONE_OS_VERSION_MIN_REQUIRED, // __IPHONE_8_0. @@ -66,6 +85,35 @@ #include "absl/base/options.h" #include "absl/base/policy_checks.h" +// Abseil long-term support (LTS) releases will define +// `ABSL_LTS_RELEASE_VERSION` to the integer representing the date string of the +// LTS release version, and will define `ABSL_LTS_RELEASE_PATCH_LEVEL` to the +// integer representing the patch-level for that release. +// +// For example, for LTS release version "20300401.2", this would give us +// ABSL_LTS_RELEASE_VERSION == 20300401 && ABSL_LTS_RELEASE_PATCH_LEVEL == 2 +// +// These symbols will not be defined in non-LTS code. +// +// Abseil recommends that clients live-at-head. Therefore, if you are using +// these symbols to assert a minimum version requirement, we recommend you do it +// as +// +// #if defined(ABSL_LTS_RELEASE_VERSION) && ABSL_LTS_RELEASE_VERSION < 20300401 +// #error Project foo requires Abseil LTS version >= 20300401 +// #endif +// +// The `defined(ABSL_LTS_RELEASE_VERSION)` part of the check excludes +// live-at-head clients from the minimum version assertion. +// +// See https://abseil.io/about/releases for more information on Abseil release +// management. +// +// LTS releases can be obtained from +// https://github.com/abseil/abseil-cpp/releases. +#define ABSL_LTS_RELEASE_VERSION 20220623 +#define ABSL_LTS_RELEASE_PATCH_LEVEL 0 + // Helper macro to convert a CPP variable to a string literal. #define ABSL_INTERNAL_DO_TOKEN_STR(x) #x #define ABSL_INTERNAL_TOKEN_STR(x) ABSL_INTERNAL_DO_TOKEN_STR(x) @@ -154,24 +202,35 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' || #define ABSL_HAVE_BUILTIN(x) 0 #endif -#if defined(__is_identifier) -#define ABSL_INTERNAL_HAS_KEYWORD(x) !(__is_identifier(x)) -#else -#define ABSL_INTERNAL_HAS_KEYWORD(x) 0 -#endif - #ifdef __has_feature #define ABSL_HAVE_FEATURE(f) __has_feature(f) #else #define ABSL_HAVE_FEATURE(f) 0 #endif +// Portable check for GCC minimum version: +// https://gcc.gnu.org/onlinedocs/cpp/Common-Predefined-Macros.html +#if defined(__GNUC__) && defined(__GNUC_MINOR__) +#define ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(x, y) \ + (__GNUC__ > (x) || __GNUC__ == (x) && __GNUC_MINOR__ >= (y)) +#else +#define ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(x, y) 0 +#endif + +#if defined(__clang__) && defined(__clang_major__) && defined(__clang_minor__) +#define ABSL_INTERNAL_HAVE_MIN_CLANG_VERSION(x, y) \ + (__clang_major__ > (x) || __clang_major__ == (x) && __clang_minor__ >= (y)) +#else +#define ABSL_INTERNAL_HAVE_MIN_CLANG_VERSION(x, y) 0 +#endif + // ABSL_HAVE_TLS is defined to 1 when __thread should be supported. -// We assume __thread is supported on Linux when compiled with Clang or compiled -// against libstdc++ with _GLIBCXX_HAVE_TLS defined. +// We assume __thread is supported on Linux or Asylo when compiled with Clang or +// compiled against libstdc++ with _GLIBCXX_HAVE_TLS defined. #ifdef ABSL_HAVE_TLS #error ABSL_HAVE_TLS cannot be directly set -#elif defined(__linux__) && (defined(__clang__) || defined(_GLIBCXX_HAVE_TLS)) +#elif (defined(__linux__) || defined(__ASYLO__)) && \ + (defined(__clang__) || defined(_GLIBCXX_HAVE_TLS)) #define ABSL_HAVE_TLS 1 #endif @@ -183,10 +242,9 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' || // gcc >= 4.8.1 using libstdc++, and Visual Studio. #ifdef ABSL_HAVE_STD_IS_TRIVIALLY_DESTRUCTIBLE #error ABSL_HAVE_STD_IS_TRIVIALLY_DESTRUCTIBLE cannot be directly set -#elif defined(_LIBCPP_VERSION) || \ - (!defined(__clang__) && defined(__GNUC__) && defined(__GLIBCXX__) && \ - (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8))) || \ - defined(_MSC_VER) +#elif defined(_LIBCPP_VERSION) || defined(_MSC_VER) || \ + (!defined(__clang__) && defined(__GLIBCXX__) && \ + ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(4, 8)) #define ABSL_HAVE_STD_IS_TRIVIALLY_DESTRUCTIBLE 1 #endif @@ -199,34 +257,22 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' || // // Checks whether `std::is_trivially_copy_assignable<T>` is supported. -// Notes: Clang with libc++ supports these features, as does gcc >= 5.1 with -// either libc++ or libstdc++, and Visual Studio (but not NVCC). +// Notes: Clang with libc++ supports these features, as does gcc >= 7.4 with +// libstdc++, or gcc >= 8.2 with libc++, and Visual Studio (but not NVCC). #if defined(ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE) #error ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE cannot be directly set #elif defined(ABSL_HAVE_STD_IS_TRIVIALLY_ASSIGNABLE) #error ABSL_HAVE_STD_IS_TRIVIALLY_ASSIGNABLE cannot directly set -#elif (defined(__clang__) && defined(_LIBCPP_VERSION)) || \ - (!defined(__clang__) && defined(__GNUC__) && \ - (__GNUC__ > 7 || (__GNUC__ == 7 && __GNUC_MINOR__ >= 4)) && \ - (defined(_LIBCPP_VERSION) || defined(__GLIBCXX__))) || \ +#elif (defined(__clang__) && defined(_LIBCPP_VERSION)) || \ + (!defined(__clang__) && \ + ((ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(7, 4) && defined(__GLIBCXX__)) || \ + (ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(8, 2) && \ + defined(_LIBCPP_VERSION)))) || \ (defined(_MSC_VER) && !defined(__NVCC__)) #define ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE 1 #define ABSL_HAVE_STD_IS_TRIVIALLY_ASSIGNABLE 1 #endif -// ABSL_HAVE_SOURCE_LOCATION_CURRENT -// -// Indicates whether `absl::SourceLocation::current()` will return useful -// information in some contexts. -#ifndef ABSL_HAVE_SOURCE_LOCATION_CURRENT -#if ABSL_INTERNAL_HAS_KEYWORD(__builtin_LINE) && \ - ABSL_INTERNAL_HAS_KEYWORD(__builtin_FILE) -#define ABSL_HAVE_SOURCE_LOCATION_CURRENT 1 -#elif defined(__GNUC__) && __GNUC__ >= 5 -#define ABSL_HAVE_SOURCE_LOCATION_CURRENT 1 -#endif -#endif - // ABSL_HAVE_THREAD_LOCAL // // Checks whether C++11's `thread_local` storage duration specifier is @@ -319,25 +365,21 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' || // For further details, consult the compiler's documentation. #ifdef ABSL_HAVE_EXCEPTIONS #error ABSL_HAVE_EXCEPTIONS cannot be directly set. - -#elif defined(__clang__) - -#if __clang_major__ > 3 || (__clang_major__ == 3 && __clang_minor__ >= 6) +#elif ABSL_INTERNAL_HAVE_MIN_CLANG_VERSION(3, 6) // Clang >= 3.6 #if ABSL_HAVE_FEATURE(cxx_exceptions) #define ABSL_HAVE_EXCEPTIONS 1 #endif // ABSL_HAVE_FEATURE(cxx_exceptions) -#else +#elif defined(__clang__) // Clang < 3.6 // http://releases.llvm.org/3.6.0/tools/clang/docs/ReleaseNotes.html#the-exceptions-macro #if defined(__EXCEPTIONS) && ABSL_HAVE_FEATURE(cxx_exceptions) #define ABSL_HAVE_EXCEPTIONS 1 #endif // defined(__EXCEPTIONS) && ABSL_HAVE_FEATURE(cxx_exceptions) -#endif // __clang_major__ > 3 || (__clang_major__ == 3 && __clang_minor__ >= 6) - // Handle remaining special cases and default to exceptions being supported. -#elif !(defined(__GNUC__) && (__GNUC__ < 5) && !defined(__EXCEPTIONS)) && \ - !(defined(__GNUC__) && (__GNUC__ >= 5) && !defined(__cpp_exceptions)) && \ +#elif !(defined(__GNUC__) && (__GNUC__ < 5) && !defined(__EXCEPTIONS)) && \ + !(ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(5, 0) && \ + !defined(__cpp_exceptions)) && \ !(defined(_MSC_VER) && !defined(_CPPUNWIND)) #define ABSL_HAVE_EXCEPTIONS 1 #endif @@ -369,10 +411,12 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' || // POSIX.1-2001. #ifdef ABSL_HAVE_MMAP #error ABSL_HAVE_MMAP cannot be directly set -#elif defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__) || \ - defined(__ros__) || defined(__native_client__) || defined(__asmjs__) || \ - defined(__wasm__) || defined(__Fuchsia__) || defined(__sun) || \ - defined(__ASYLO__) || defined(__myriad2__) +#elif defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__) || \ + defined(_AIX) || defined(__ros__) || defined(__native_client__) || \ + defined(__asmjs__) || defined(__wasm__) || defined(__Fuchsia__) || \ + defined(__sun) || defined(__ASYLO__) || defined(__myriad2__) || \ + defined(__HAIKU__) || defined(__OpenBSD__) || defined(__NetBSD__) || \ + defined(__QNX__) #define ABSL_HAVE_MMAP 1 #endif @@ -383,7 +427,8 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' || #ifdef ABSL_HAVE_PTHREAD_GETSCHEDPARAM #error ABSL_HAVE_PTHREAD_GETSCHEDPARAM cannot be directly set #elif defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__) || \ - defined(__ros__) + defined(_AIX) || defined(__ros__) || defined(__OpenBSD__) || \ + defined(__NetBSD__) #define ABSL_HAVE_PTHREAD_GETSCHEDPARAM 1 #endif @@ -478,22 +523,41 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' || #error "absl endian detection needs to be set up for your compiler" #endif -// macOS 10.13 and iOS 10.11 don't let you use <any>, <optional>, or <variant> -// even though the headers exist and are publicly noted to work. See -// https://github.com/abseil/abseil-cpp/issues/207 and +// macOS < 10.13 and iOS < 11 don't let you use <any>, <optional>, or <variant> +// even though the headers exist and are publicly noted to work, because the +// libc++ shared library shipped on the system doesn't have the requisite +// exported symbols. See https://github.com/abseil/abseil-cpp/issues/207 and // https://developer.apple.com/documentation/xcode_release_notes/xcode_10_release_notes +// // libc++ spells out the availability requirements in the file // llvm-project/libcxx/include/__config via the #define // _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS. -#if defined(__APPLE__) && defined(_LIBCPP_VERSION) && \ - ((defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && \ - __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101400) || \ - (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && \ - __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 120000) || \ - (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && \ - __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 50000) || \ - (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && \ - __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 120000)) +// +// Unfortunately, Apple initially mis-stated the requirements as macOS < 10.14 +// and iOS < 12 in the libc++ headers. This was corrected by +// https://github.com/llvm/llvm-project/commit/7fb40e1569dd66292b647f4501b85517e9247953 +// which subsequently made it into the XCode 12.5 release. We need to match the +// old (incorrect) conditions when built with old XCode, but can use the +// corrected earlier versions with new XCode. +#if defined(__APPLE__) && defined(_LIBCPP_VERSION) && \ + ((_LIBCPP_VERSION >= 11000 && /* XCode 12.5 or later: */ \ + ((defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && \ + __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101300) || \ + (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && \ + __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 110000) || \ + (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && \ + __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 40000) || \ + (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && \ + __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 110000))) || \ + (_LIBCPP_VERSION < 11000 && /* Pre-XCode 12.5: */ \ + ((defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && \ + __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101400) || \ + (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && \ + __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 120000) || \ + (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) && \ + __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 50000) || \ + (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && \ + __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 120000)))) #define ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE 1 #else #define ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE 0 @@ -663,8 +727,6 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' || #endif #endif -#undef ABSL_INTERNAL_HAS_KEYWORD - // ABSL_DLL // // When building Abseil as a DLL, this macro expands to `__declspec(dllexport)` @@ -690,12 +752,6 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' || // a compiler instrumentation module and a run-time library. #ifdef ABSL_HAVE_MEMORY_SANITIZER #error "ABSL_HAVE_MEMORY_SANITIZER cannot be directly set." -#elif defined(MEMORY_SANITIZER) -// The MEMORY_SANITIZER macro is deprecated but we will continue to honor it -// for now. -#define ABSL_HAVE_MEMORY_SANITIZER 1 -#elif defined(__SANITIZE_MEMORY__) -#define ABSL_HAVE_MEMORY_SANITIZER 1 #elif !defined(__native_client__) && ABSL_HAVE_FEATURE(memory_sanitizer) #define ABSL_HAVE_MEMORY_SANITIZER 1 #endif @@ -705,10 +761,6 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' || // ThreadSanitizer (TSan) is a fast data race detector. #ifdef ABSL_HAVE_THREAD_SANITIZER #error "ABSL_HAVE_THREAD_SANITIZER cannot be directly set." -#elif defined(THREAD_SANITIZER) -// The THREAD_SANITIZER macro is deprecated but we will continue to honor it -// for now. -#define ABSL_HAVE_THREAD_SANITIZER 1 #elif defined(__SANITIZE_THREAD__) #define ABSL_HAVE_THREAD_SANITIZER 1 #elif ABSL_HAVE_FEATURE(thread_sanitizer) @@ -720,16 +772,51 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' || // AddressSanitizer (ASan) is a fast memory error detector. #ifdef ABSL_HAVE_ADDRESS_SANITIZER #error "ABSL_HAVE_ADDRESS_SANITIZER cannot be directly set." -#elif defined(ADDRESS_SANITIZER) -// The ADDRESS_SANITIZER macro is deprecated but we will continue to honor it -// for now. -#define ABSL_HAVE_ADDRESS_SANITIZER 1 #elif defined(__SANITIZE_ADDRESS__) #define ABSL_HAVE_ADDRESS_SANITIZER 1 #elif ABSL_HAVE_FEATURE(address_sanitizer) #define ABSL_HAVE_ADDRESS_SANITIZER 1 #endif +// ABSL_HAVE_HWADDRESS_SANITIZER +// +// Hardware-Assisted AddressSanitizer (or HWASAN) is even faster than asan +// memory error detector which can use CPU features like ARM TBI, Intel LAM or +// AMD UAI. +#ifdef ABSL_HAVE_HWADDRESS_SANITIZER +#error "ABSL_HAVE_HWADDRESS_SANITIZER cannot be directly set." +#elif defined(__SANITIZE_HWADDRESS__) +#define ABSL_HAVE_HWADDRESS_SANITIZER 1 +#elif ABSL_HAVE_FEATURE(hwaddress_sanitizer) +#define ABSL_HAVE_HWADDRESS_SANITIZER 1 +#endif + +// ABSL_HAVE_LEAK_SANITIZER +// +// LeakSanitizer (or lsan) is a detector of memory leaks. +// https://clang.llvm.org/docs/LeakSanitizer.html +// https://github.com/google/sanitizers/wiki/AddressSanitizerLeakSanitizer +// +// The macro ABSL_HAVE_LEAK_SANITIZER can be used to detect at compile-time +// whether the LeakSanitizer is potentially available. However, just because the +// LeakSanitizer is available does not mean it is active. Use the +// always-available run-time interface in //absl/debugging/leak_check.h for +// interacting with LeakSanitizer. +#ifdef ABSL_HAVE_LEAK_SANITIZER +#error "ABSL_HAVE_LEAK_SANITIZER cannot be directly set." +#elif defined(LEAK_SANITIZER) +// GCC provides no method for detecting the presense of the standalone +// LeakSanitizer (-fsanitize=leak), so GCC users of -fsanitize=leak should also +// use -DLEAK_SANITIZER. +#define ABSL_HAVE_LEAK_SANITIZER 1 +// Clang standalone LeakSanitizer (-fsanitize=leak) +#elif ABSL_HAVE_FEATURE(leak_sanitizer) +#define ABSL_HAVE_LEAK_SANITIZER 1 +#elif defined(ABSL_HAVE_ADDRESS_SANITIZER) +// GCC or Clang using the LeakSanitizer integrated into AddressSanitizer. +#define ABSL_HAVE_LEAK_SANITIZER 1 +#endif + // ABSL_HAVE_CLASS_TEMPLATE_ARGUMENT_DEDUCTION // // Class template argument deduction is a language feature added in C++17. @@ -739,4 +826,88 @@ static_assert(ABSL_INTERNAL_INLINE_NAMESPACE_STR[0] != 'h' || #define ABSL_HAVE_CLASS_TEMPLATE_ARGUMENT_DEDUCTION 1 #endif +// ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL +// +// Prior to C++17, static constexpr variables defined in classes required a +// separate definition outside of the class body, for example: +// +// class Foo { +// static constexpr int kBar = 0; +// }; +// constexpr int Foo::kBar; +// +// In C++17, these variables defined in classes are considered inline variables, +// and the extra declaration is redundant. Since some compilers warn on the +// extra declarations, ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL can be used +// conditionally ignore them: +// +// #ifdef ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL +// constexpr int Foo::kBar; +// #endif +#if defined(ABSL_INTERNAL_CPLUSPLUS_LANG) && \ + ABSL_INTERNAL_CPLUSPLUS_LANG < 201703L +#define ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL 1 +#endif + +// `ABSL_INTERNAL_HAS_RTTI` determines whether abseil is being compiled with +// RTTI support. +#ifdef ABSL_INTERNAL_HAS_RTTI +#error ABSL_INTERNAL_HAS_RTTI cannot be directly set +#elif !defined(__GNUC__) || defined(__GXX_RTTI) +#define ABSL_INTERNAL_HAS_RTTI 1 +#endif // !defined(__GNUC__) || defined(__GXX_RTTI) + +// ABSL_INTERNAL_HAVE_SSE is used for compile-time detection of SSE support. +// See https://gcc.gnu.org/onlinedocs/gcc/x86-Options.html for an overview of +// which architectures support the various x86 instruction sets. +#ifdef ABSL_INTERNAL_HAVE_SSE +#error ABSL_INTERNAL_HAVE_SSE cannot be directly set +#elif defined(__SSE__) +#define ABSL_INTERNAL_HAVE_SSE 1 +#elif defined(_M_X64) || (defined(_M_IX86_FP) && _M_IX86_FP >= 1) +// MSVC only defines _M_IX86_FP for x86 32-bit code, and _M_IX86_FP >= 1 +// indicates that at least SSE was targeted with the /arch:SSE option. +// All x86-64 processors support SSE, so support can be assumed. +// https://docs.microsoft.com/en-us/cpp/preprocessor/predefined-macros +#define ABSL_INTERNAL_HAVE_SSE 1 +#endif + +// ABSL_INTERNAL_HAVE_SSE2 is used for compile-time detection of SSE2 support. +// See https://gcc.gnu.org/onlinedocs/gcc/x86-Options.html for an overview of +// which architectures support the various x86 instruction sets. +#ifdef ABSL_INTERNAL_HAVE_SSE2 +#error ABSL_INTERNAL_HAVE_SSE2 cannot be directly set +#elif defined(__SSE2__) +#define ABSL_INTERNAL_HAVE_SSE2 1 +#elif defined(_M_X64) || (defined(_M_IX86_FP) && _M_IX86_FP >= 2) +// MSVC only defines _M_IX86_FP for x86 32-bit code, and _M_IX86_FP >= 2 +// indicates that at least SSE2 was targeted with the /arch:SSE2 option. +// All x86-64 processors support SSE2, so support can be assumed. +// https://docs.microsoft.com/en-us/cpp/preprocessor/predefined-macros +#define ABSL_INTERNAL_HAVE_SSE2 1 +#endif + +// ABSL_INTERNAL_HAVE_SSSE3 is used for compile-time detection of SSSE3 support. +// See https://gcc.gnu.org/onlinedocs/gcc/x86-Options.html for an overview of +// which architectures support the various x86 instruction sets. +// +// MSVC does not have a mode that targets SSSE3 at compile-time. To use SSSE3 +// with MSVC requires either assuming that the code will only every run on CPUs +// that support SSSE3, otherwise __cpuid() can be used to detect support at +// runtime and fallback to a non-SSSE3 implementation when SSSE3 is unsupported +// by the CPU. +#ifdef ABSL_INTERNAL_HAVE_SSSE3 +#error ABSL_INTERNAL_HAVE_SSSE3 cannot be directly set +#elif defined(__SSSE3__) +#define ABSL_INTERNAL_HAVE_SSSE3 1 +#endif + +// ABSL_INTERNAL_HAVE_ARM_NEON is used for compile-time detection of NEON (ARM +// SIMD). +#ifdef ABSL_INTERNAL_HAVE_ARM_NEON +#error ABSL_INTERNAL_HAVE_ARM_NEON cannot be directly set +#elif defined(__ARM_NEON) +#define ABSL_INTERNAL_HAVE_ARM_NEON 1 +#endif + #endif // ABSL_BASE_CONFIG_H_ |