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420 lines
15 KiB
420 lines
15 KiB
5 years ago
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// Copyright 2013 the V8 project authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#ifndef V8CONFIG_H_
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#define V8CONFIG_H_
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// Platform headers for feature detection below.
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#if defined(__ANDROID__)
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# include <sys/cdefs.h>
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#elif defined(__APPLE__)
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# include <TargetConditionals.h>
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#elif defined(__linux__)
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# include <features.h>
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#endif
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// This macro allows to test for the version of the GNU C library (or
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// a compatible C library that masquerades as glibc). It evaluates to
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// 0 if libc is not GNU libc or compatible.
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// Use like:
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// #if V8_GLIBC_PREREQ(2, 3)
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// ...
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// #endif
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#if defined(__GLIBC__) && defined(__GLIBC_MINOR__)
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# define V8_GLIBC_PREREQ(major, minor) \
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((__GLIBC__ * 100 + __GLIBC_MINOR__) >= ((major) * 100 + (minor)))
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#else
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# define V8_GLIBC_PREREQ(major, minor) 0
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#endif
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// This macro allows to test for the version of the GNU C++ compiler.
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// Note that this also applies to compilers that masquerade as GCC,
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// for example clang and the Intel C++ compiler for Linux.
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// Use like:
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// #if V8_GNUC_PREREQ(4, 3, 1)
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// ...
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// #endif
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#if defined(__GNUC__) && defined(__GNUC_MINOR__) && defined(__GNUC_PATCHLEVEL__)
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# define V8_GNUC_PREREQ(major, minor, patchlevel) \
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((__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) >= \
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((major) * 10000 + (minor) * 100 + (patchlevel)))
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#elif defined(__GNUC__) && defined(__GNUC_MINOR__)
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# define V8_GNUC_PREREQ(major, minor, patchlevel) \
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((__GNUC__ * 10000 + __GNUC_MINOR__) >= \
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((major) * 10000 + (minor) * 100 + (patchlevel)))
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#else
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# define V8_GNUC_PREREQ(major, minor, patchlevel) 0
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#endif
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// -----------------------------------------------------------------------------
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// Operating system detection
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//
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// V8_OS_ANDROID - Android
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// V8_OS_BSD - BSDish (Mac OS X, Net/Free/Open/DragonFlyBSD)
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// V8_OS_CYGWIN - Cygwin
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// V8_OS_DRAGONFLYBSD - DragonFlyBSD
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// V8_OS_FREEBSD - FreeBSD
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// V8_OS_LINUX - Linux
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// V8_OS_MACOSX - Mac OS X
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// V8_OS_NACL - Native Client
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// V8_OS_NETBSD - NetBSD
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// V8_OS_OPENBSD - OpenBSD
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// V8_OS_POSIX - POSIX compatible (mostly everything except Windows)
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// V8_OS_QNX - QNX Neutrino
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// V8_OS_SOLARIS - Sun Solaris and OpenSolaris
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// V8_OS_WIN - Microsoft Windows
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#if defined(__ANDROID__)
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# define V8_OS_ANDROID 1
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# define V8_OS_LINUX 1
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# define V8_OS_POSIX 1
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#elif defined(__APPLE__)
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# define V8_OS_BSD 1
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# define V8_OS_MACOSX 1
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# define V8_OS_POSIX 1
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#elif defined(__native_client__)
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# define V8_OS_NACL 1
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# define V8_OS_POSIX 1
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#elif defined(__CYGWIN__)
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# define V8_OS_CYGWIN 1
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# define V8_OS_POSIX 1
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#elif defined(__linux__)
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# define V8_OS_LINUX 1
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# define V8_OS_POSIX 1
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#elif defined(__sun)
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# define V8_OS_POSIX 1
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# define V8_OS_SOLARIS 1
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#elif defined(__FreeBSD__)
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# define V8_OS_BSD 1
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# define V8_OS_FREEBSD 1
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# define V8_OS_POSIX 1
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#elif defined(__DragonFly__)
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# define V8_OS_BSD 1
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# define V8_OS_DRAGONFLYBSD 1
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# define V8_OS_POSIX 1
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#elif defined(__NetBSD__)
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# define V8_OS_BSD 1
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# define V8_OS_NETBSD 1
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# define V8_OS_POSIX 1
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#elif defined(__OpenBSD__)
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# define V8_OS_BSD 1
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# define V8_OS_OPENBSD 1
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# define V8_OS_POSIX 1
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#elif defined(__QNXNTO__)
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# define V8_OS_POSIX 1
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# define V8_OS_QNX 1
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#elif defined(_WIN32)
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# define V8_OS_WIN 1
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#endif
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// -----------------------------------------------------------------------------
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// C library detection
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//
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// V8_LIBC_MSVCRT - MSVC libc
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// V8_LIBC_BIONIC - Bionic libc
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// V8_LIBC_BSD - BSD libc derivate
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// V8_LIBC_GLIBC - GNU C library
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// V8_LIBC_UCLIBC - uClibc
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//
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// Note that testing for libc must be done using #if not #ifdef. For example,
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// to test for the GNU C library, use:
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// #if V8_LIBC_GLIBC
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// ...
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// #endif
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#if defined (_MSC_VER)
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# define V8_LIBC_MSVCRT 1
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#elif defined(__BIONIC__)
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# define V8_LIBC_BIONIC 1
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# define V8_LIBC_BSD 1
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#elif defined(__UCLIBC__)
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# define V8_LIBC_UCLIBC 1
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#elif defined(__GLIBC__) || defined(__GNU_LIBRARY__)
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# define V8_LIBC_GLIBC 1
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#else
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# define V8_LIBC_BSD V8_OS_BSD
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#endif
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// -----------------------------------------------------------------------------
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// Compiler detection
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//
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// V8_CC_CLANG - Clang
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// V8_CC_GNU - GNU C++
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// V8_CC_INTEL - Intel C++
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// V8_CC_MINGW - Minimalist GNU for Windows
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// V8_CC_MINGW32 - Minimalist GNU for Windows (mingw32)
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// V8_CC_MINGW64 - Minimalist GNU for Windows (mingw-w64)
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// V8_CC_MSVC - Microsoft Visual C/C++
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//
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// C++11 feature detection
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//
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// V8_HAS_CXX11_ALIGNAS - alignas specifier supported
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// V8_HAS_CXX11_ALIGNOF - alignof(type) operator supported
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// V8_HAS_CXX11_STATIC_ASSERT - static_assert() supported
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// V8_HAS_CXX11_DELETE - deleted functions supported
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// V8_HAS_CXX11_FINAL - final marker supported
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// V8_HAS_CXX11_OVERRIDE - override marker supported
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//
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// Compiler-specific feature detection
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//
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// V8_HAS___ALIGNOF - __alignof(type) operator supported
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// V8_HAS___ALIGNOF__ - __alignof__(type) operator supported
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// V8_HAS_ATTRIBUTE_ALIGNED - __attribute__((aligned(n))) supported
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// V8_HAS_ATTRIBUTE_ALWAYS_INLINE - __attribute__((always_inline))
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// supported
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// V8_HAS_ATTRIBUTE_DEPRECATED - __attribute__((deprecated)) supported
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// V8_HAS_ATTRIBUTE_NOINLINE - __attribute__((noinline)) supported
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// V8_HAS_ATTRIBUTE_UNUSED - __attribute__((unused)) supported
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// V8_HAS_ATTRIBUTE_VISIBILITY - __attribute__((visibility)) supported
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// V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT - __attribute__((warn_unused_result))
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// supported
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// V8_HAS_BUILTIN_CLZ - __builtin_clz() supported
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// V8_HAS_BUILTIN_CTZ - __builtin_ctz() supported
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// V8_HAS_BUILTIN_EXPECT - __builtin_expect() supported
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// V8_HAS_BUILTIN_POPCOUNT - __builtin_popcount() supported
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// V8_HAS_BUILTIN_SADD_OVERFLOW - __builtin_sadd_overflow() supported
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// V8_HAS_BUILTIN_SSUB_OVERFLOW - __builtin_ssub_overflow() supported
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// V8_HAS_DECLSPEC_ALIGN - __declspec(align(n)) supported
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// V8_HAS_DECLSPEC_DEPRECATED - __declspec(deprecated) supported
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// V8_HAS_DECLSPEC_NOINLINE - __declspec(noinline) supported
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// V8_HAS___FINAL - __final supported in non-C++11 mode
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// V8_HAS___FORCEINLINE - __forceinline supported
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// V8_HAS_SEALED - MSVC style sealed marker supported
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//
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// Note that testing for compilers and/or features must be done using #if
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// not #ifdef. For example, to test for Intel C++ Compiler, use:
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// #if V8_CC_INTEL
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// ...
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// #endif
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#if defined(__clang__)
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# define V8_CC_CLANG 1
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// Clang defines __alignof__ as alias for __alignof
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# define V8_HAS___ALIGNOF 1
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# define V8_HAS___ALIGNOF__ V8_HAS___ALIGNOF
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# define V8_HAS_ATTRIBUTE_ALIGNED (__has_attribute(aligned))
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# define V8_HAS_ATTRIBUTE_ALWAYS_INLINE (__has_attribute(always_inline))
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# define V8_HAS_ATTRIBUTE_DEPRECATED (__has_attribute(deprecated))
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# define V8_HAS_ATTRIBUTE_NOINLINE (__has_attribute(noinline))
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# define V8_HAS_ATTRIBUTE_UNUSED (__has_attribute(unused))
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# define V8_HAS_ATTRIBUTE_VISIBILITY (__has_attribute(visibility))
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# define V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT \
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(__has_attribute(warn_unused_result))
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# define V8_HAS_BUILTIN_CLZ (__has_builtin(__builtin_clz))
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# define V8_HAS_BUILTIN_CTZ (__has_builtin(__builtin_ctz))
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# define V8_HAS_BUILTIN_EXPECT (__has_builtin(__builtin_expect))
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# define V8_HAS_BUILTIN_POPCOUNT (__has_builtin(__builtin_popcount))
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# define V8_HAS_BUILTIN_SADD_OVERFLOW (__has_builtin(__builtin_sadd_overflow))
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# define V8_HAS_BUILTIN_SSUB_OVERFLOW (__has_builtin(__builtin_ssub_overflow))
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# define V8_HAS_CXX11_ALIGNAS (__has_feature(cxx_alignas))
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# define V8_HAS_CXX11_STATIC_ASSERT (__has_feature(cxx_static_assert))
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# define V8_HAS_CXX11_DELETE (__has_feature(cxx_deleted_functions))
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# define V8_HAS_CXX11_FINAL (__has_feature(cxx_override_control))
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# define V8_HAS_CXX11_OVERRIDE (__has_feature(cxx_override_control))
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#elif defined(__GNUC__)
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# define V8_CC_GNU 1
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// Intel C++ also masquerades as GCC 3.2.0
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# define V8_CC_INTEL (defined(__INTEL_COMPILER))
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# define V8_CC_MINGW32 (defined(__MINGW32__))
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# define V8_CC_MINGW64 (defined(__MINGW64__))
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# define V8_CC_MINGW (V8_CC_MINGW32 || V8_CC_MINGW64)
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# define V8_HAS___ALIGNOF__ (V8_GNUC_PREREQ(4, 3, 0))
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# define V8_HAS_ATTRIBUTE_ALIGNED (V8_GNUC_PREREQ(2, 95, 0))
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// always_inline is available in gcc 4.0 but not very reliable until 4.4.
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// Works around "sorry, unimplemented: inlining failed" build errors with
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// older compilers.
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# define V8_HAS_ATTRIBUTE_ALWAYS_INLINE (V8_GNUC_PREREQ(4, 4, 0))
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# define V8_HAS_ATTRIBUTE_DEPRECATED (V8_GNUC_PREREQ(3, 4, 0))
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# define V8_HAS_ATTRIBUTE_DEPRECATED_MESSAGE (V8_GNUC_PREREQ(4, 5, 0))
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# define V8_HAS_ATTRIBUTE_NOINLINE (V8_GNUC_PREREQ(3, 4, 0))
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# define V8_HAS_ATTRIBUTE_UNUSED (V8_GNUC_PREREQ(2, 95, 0))
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# define V8_HAS_ATTRIBUTE_VISIBILITY (V8_GNUC_PREREQ(4, 3, 0))
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# define V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT \
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(!V8_CC_INTEL && V8_GNUC_PREREQ(4, 1, 0))
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# define V8_HAS_BUILTIN_CLZ (V8_GNUC_PREREQ(3, 4, 0))
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# define V8_HAS_BUILTIN_CTZ (V8_GNUC_PREREQ(3, 4, 0))
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# define V8_HAS_BUILTIN_EXPECT (V8_GNUC_PREREQ(2, 96, 0))
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# define V8_HAS_BUILTIN_POPCOUNT (V8_GNUC_PREREQ(3, 4, 0))
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// g++ requires -std=c++0x or -std=gnu++0x to support C++11 functionality
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// without warnings (functionality used by the macros below). These modes
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// are detectable by checking whether __GXX_EXPERIMENTAL_CXX0X__ is defined or,
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// more standardly, by checking whether __cplusplus has a C++11 or greater
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// value. Current versions of g++ do not correctly set __cplusplus, so we check
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// both for forward compatibility.
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# if defined(__GXX_EXPERIMENTAL_CXX0X__) || __cplusplus >= 201103L
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# define V8_HAS_CXX11_ALIGNAS (V8_GNUC_PREREQ(4, 8, 0))
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# define V8_HAS_CXX11_ALIGNOF (V8_GNUC_PREREQ(4, 8, 0))
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# define V8_HAS_CXX11_STATIC_ASSERT (V8_GNUC_PREREQ(4, 3, 0))
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# define V8_HAS_CXX11_DELETE (V8_GNUC_PREREQ(4, 4, 0))
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# define V8_HAS_CXX11_OVERRIDE (V8_GNUC_PREREQ(4, 7, 0))
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# define V8_HAS_CXX11_FINAL (V8_GNUC_PREREQ(4, 7, 0))
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# else
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// '__final' is a non-C++11 GCC synonym for 'final', per GCC r176655.
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# define V8_HAS___FINAL (V8_GNUC_PREREQ(4, 7, 0))
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# endif
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#elif defined(_MSC_VER)
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# define V8_CC_MSVC 1
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# define V8_HAS___ALIGNOF 1
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// Override control was added with Visual Studio 2005, but
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// Visual Studio 2010 and earlier spell "final" as "sealed".
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# define V8_HAS_CXX11_FINAL (_MSC_VER >= 1700)
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# define V8_HAS_CXX11_OVERRIDE (_MSC_VER >= 1400)
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# define V8_HAS_SEALED (_MSC_VER >= 1400)
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# define V8_HAS_DECLSPEC_ALIGN 1
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# define V8_HAS_DECLSPEC_DEPRECATED (_MSC_VER >= 1300)
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# define V8_HAS_DECLSPEC_NOINLINE 1
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# define V8_HAS___FORCEINLINE 1
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#endif
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// -----------------------------------------------------------------------------
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// Helper macros
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// A macro used to make better inlining. Don't bother for debug builds.
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// Use like:
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// V8_INLINE int GetZero() { return 0; }
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#if !defined(DEBUG) && V8_HAS_ATTRIBUTE_ALWAYS_INLINE
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# define V8_INLINE inline __attribute__((always_inline))
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#elif !defined(DEBUG) && V8_HAS___FORCEINLINE
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# define V8_INLINE __forceinline
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#else
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# define V8_INLINE inline
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#endif
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// A macro used to tell the compiler to never inline a particular function.
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// Don't bother for debug builds.
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// Use like:
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// V8_NOINLINE int GetMinusOne() { return -1; }
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#if !defined(DEBUG) && V8_HAS_ATTRIBUTE_NOINLINE
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# define V8_NOINLINE __attribute__((noinline))
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#elif !defined(DEBUG) && V8_HAS_DECLSPEC_NOINLINE
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# define V8_NOINLINE __declspec(noinline)
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#else
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# define V8_NOINLINE /* NOT SUPPORTED */
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#endif
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// A macro to mark classes or functions as deprecated.
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#if defined(V8_DEPRECATION_WARNINGS) && V8_HAS_ATTRIBUTE_DEPRECATED_MESSAGE
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# define V8_DEPRECATED(message, declarator) \
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declarator __attribute__((deprecated(message)))
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#elif defined(V8_DEPRECATION_WARNINGS) && V8_HAS_ATTRIBUTE_DEPRECATED
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# define V8_DEPRECATED(message, declarator) \
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declarator __attribute__((deprecated))
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#elif defined(V8_DEPRECATION_WARNINGS) && V8_HAS_DECLSPEC_DEPRECATED
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# define V8_DEPRECATED(message, declarator) __declspec(deprecated) declarator
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#else
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# define V8_DEPRECATED(message, declarator) declarator
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#endif
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// A macro to provide the compiler with branch prediction information.
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#if V8_HAS_BUILTIN_EXPECT
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# define V8_UNLIKELY(condition) (__builtin_expect(!!(condition), 0))
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# define V8_LIKELY(condition) (__builtin_expect(!!(condition), 1))
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#else
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# define V8_UNLIKELY(condition) (condition)
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||
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# define V8_LIKELY(condition) (condition)
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#endif
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// A macro to specify that a method is deleted from the corresponding class.
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||
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// Any attempt to use the method will always produce an error at compile time
|
||
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// when this macro can be implemented (i.e. if the compiler supports C++11).
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||
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// If the current compiler does not support C++11, use of the annotated method
|
||
|
// will still cause an error, but the error will most likely occur at link time
|
||
|
// rather than at compile time. As a backstop, method declarations using this
|
||
|
// macro should be private.
|
||
|
// Use like:
|
||
|
// class A {
|
||
|
// private:
|
||
|
// A(const A& other) V8_DELETE;
|
||
|
// A& operator=(const A& other) V8_DELETE;
|
||
|
// };
|
||
|
#if V8_HAS_CXX11_DELETE
|
||
|
# define V8_DELETE = delete
|
||
|
#else
|
||
|
# define V8_DELETE /* NOT SUPPORTED */
|
||
|
#endif
|
||
|
|
||
|
|
||
|
// This macro allows to specify memory alignment for structs, classes, etc.
|
||
|
// Use like:
|
||
|
// class V8_ALIGNED(16) MyClass { ... };
|
||
|
// V8_ALIGNED(32) int array[42];
|
||
|
#if V8_HAS_CXX11_ALIGNAS
|
||
|
# define V8_ALIGNED(n) alignas(n)
|
||
|
#elif V8_HAS_ATTRIBUTE_ALIGNED
|
||
|
# define V8_ALIGNED(n) __attribute__((aligned(n)))
|
||
|
#elif V8_HAS_DECLSPEC_ALIGN
|
||
|
# define V8_ALIGNED(n) __declspec(align(n))
|
||
|
#else
|
||
|
# define V8_ALIGNED(n) /* NOT SUPPORTED */
|
||
|
#endif
|
||
|
|
||
|
|
||
|
// This macro is similar to V8_ALIGNED(), but takes a type instead of size
|
||
|
// in bytes. If the compiler does not supports using the alignment of the
|
||
|
// |type|, it will align according to the |alignment| instead. For example,
|
||
|
// Visual Studio C++ cannot combine __declspec(align) and __alignof. The
|
||
|
// |alignment| must be a literal that is used as a kind of worst-case fallback
|
||
|
// alignment.
|
||
|
// Use like:
|
||
|
// struct V8_ALIGNAS(AnotherClass, 16) NewClass { ... };
|
||
|
// V8_ALIGNAS(double, 8) int array[100];
|
||
|
#if V8_HAS_CXX11_ALIGNAS
|
||
|
# define V8_ALIGNAS(type, alignment) alignas(type)
|
||
|
#elif V8_HAS___ALIGNOF__ && V8_HAS_ATTRIBUTE_ALIGNED
|
||
|
# define V8_ALIGNAS(type, alignment) __attribute__((aligned(__alignof__(type))))
|
||
|
#else
|
||
|
# define V8_ALIGNAS(type, alignment) V8_ALIGNED(alignment)
|
||
|
#endif
|
||
|
|
||
|
|
||
|
// This macro returns alignment in bytes (an integer power of two) required for
|
||
|
// any instance of the given type, which is either complete type, an array type,
|
||
|
// or a reference type.
|
||
|
// Use like:
|
||
|
// size_t alignment = V8_ALIGNOF(double);
|
||
|
#if V8_HAS_CXX11_ALIGNOF
|
||
|
# define V8_ALIGNOF(type) alignof(type)
|
||
|
#elif V8_HAS___ALIGNOF
|
||
|
# define V8_ALIGNOF(type) __alignof(type)
|
||
|
#elif V8_HAS___ALIGNOF__
|
||
|
# define V8_ALIGNOF(type) __alignof__(type)
|
||
|
#else
|
||
|
// Note that alignment of a type within a struct can be less than the
|
||
|
// alignment of the type stand-alone (because of ancient ABIs), so this
|
||
|
// should only be used as a last resort.
|
||
|
namespace v8 { template <typename T> class AlignOfHelper { char c; T t; }; }
|
||
|
# define V8_ALIGNOF(type) (sizeof(::v8::AlignOfHelper<type>) - sizeof(type))
|
||
|
#endif
|
||
|
|
||
|
#endif // V8CONFIG_H_
|