1// Copyright 2013 the V8 project authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#ifndef V8CONFIG_H_ 6#define V8CONFIG_H_ 7 8// Platform headers for feature detection below. 9#if defined(__ANDROID__) 10# include <sys/cdefs.h> 11#elif defined(__APPLE__) 12# include <TargetConditionals.h> 13#elif defined(__linux__) 14# include <features.h> 15#endif 16 17 18// This macro allows to test for the version of the GNU C library (or 19// a compatible C library that masquerades as glibc). It evaluates to 20// 0 if libc is not GNU libc or compatible. 21// Use like: 22// #if V8_GLIBC_PREREQ(2, 3) 23// ... 24// #endif 25#if defined(__GLIBC__) && defined(__GLIBC_MINOR__) 26# define V8_GLIBC_PREREQ(major, minor) \ 27 ((__GLIBC__ * 100 + __GLIBC_MINOR__) >= ((major) * 100 + (minor))) 28#else 29# define V8_GLIBC_PREREQ(major, minor) 0 30#endif 31 32 33// This macro allows to test for the version of the GNU C++ compiler. 34// Note that this also applies to compilers that masquerade as GCC, 35// for example clang and the Intel C++ compiler for Linux. 36// Use like: 37// #if V8_GNUC_PREREQ(4, 3, 1) 38// ... 39// #endif 40#if defined(__GNUC__) && defined(__GNUC_MINOR__) && defined(__GNUC_PATCHLEVEL__) 41# define V8_GNUC_PREREQ(major, minor, patchlevel) \ 42 ((__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) >= \ 43 ((major) * 10000 + (minor) * 100 + (patchlevel))) 44#elif defined(__GNUC__) && defined(__GNUC_MINOR__) 45# define V8_GNUC_PREREQ(major, minor, patchlevel) \ 46 ((__GNUC__ * 10000 + __GNUC_MINOR__) >= \ 47 ((major) * 10000 + (minor) * 100 + (patchlevel))) 48#else 49# define V8_GNUC_PREREQ(major, minor, patchlevel) 0 50#endif 51 52 53 54// ----------------------------------------------------------------------------- 55// Operating system detection 56// 57// V8_OS_ANDROID - Android 58// V8_OS_BSD - BSDish (Mac OS X, Net/Free/Open/DragonFlyBSD) 59// V8_OS_CYGWIN - Cygwin 60// V8_OS_DRAGONFLYBSD - DragonFlyBSD 61// V8_OS_FREEBSD - FreeBSD 62// V8_OS_LINUX - Linux 63// V8_OS_MACOSX - Mac OS X 64// V8_OS_NACL - Native Client 65// V8_OS_NETBSD - NetBSD 66// V8_OS_OPENBSD - OpenBSD 67// V8_OS_POSIX - POSIX compatible (mostly everything except Windows) 68// V8_OS_QNX - QNX Neutrino 69// V8_OS_SOLARIS - Sun Solaris and OpenSolaris 70// V8_OS_WIN - Microsoft Windows 71 72#if defined(__ANDROID__) 73# define V8_OS_ANDROID 1 74# define V8_OS_LINUX 1 75# define V8_OS_POSIX 1 76#elif defined(__APPLE__) 77# define V8_OS_BSD 1 78# define V8_OS_MACOSX 1 79# define V8_OS_POSIX 1 80#elif defined(__native_client__) 81# define V8_OS_NACL 1 82# define V8_OS_POSIX 1 83#elif defined(__CYGWIN__) 84# define V8_OS_CYGWIN 1 85# define V8_OS_POSIX 1 86#elif defined(__linux__) 87# define V8_OS_LINUX 1 88# define V8_OS_POSIX 1 89#elif defined(__sun) 90# define V8_OS_POSIX 1 91# define V8_OS_SOLARIS 1 92#elif defined(__FreeBSD__) 93# define V8_OS_BSD 1 94# define V8_OS_FREEBSD 1 95# define V8_OS_POSIX 1 96#elif defined(__DragonFly__) 97# define V8_OS_BSD 1 98# define V8_OS_DRAGONFLYBSD 1 99# define V8_OS_POSIX 1 100#elif defined(__NetBSD__) 101# define V8_OS_BSD 1 102# define V8_OS_NETBSD 1 103# define V8_OS_POSIX 1 104#elif defined(__OpenBSD__) 105# define V8_OS_BSD 1 106# define V8_OS_OPENBSD 1 107# define V8_OS_POSIX 1 108#elif defined(__QNXNTO__) 109# define V8_OS_POSIX 1 110# define V8_OS_QNX 1 111#elif defined(_WIN32) 112# define V8_OS_WIN 1 113#endif 114 115 116// ----------------------------------------------------------------------------- 117// C library detection 118// 119// V8_LIBC_MSVCRT - MSVC libc 120// V8_LIBC_BIONIC - Bionic libc 121// V8_LIBC_BSD - BSD libc derivate 122// V8_LIBC_GLIBC - GNU C library 123// V8_LIBC_UCLIBC - uClibc 124// 125// Note that testing for libc must be done using #if not #ifdef. For example, 126// to test for the GNU C library, use: 127// #if V8_LIBC_GLIBC 128// ... 129// #endif 130 131#if defined (_MSC_VER) 132# define V8_LIBC_MSVCRT 1 133#elif defined(__BIONIC__) 134# define V8_LIBC_BIONIC 1 135# define V8_LIBC_BSD 1 136#elif defined(__UCLIBC__) 137# define V8_LIBC_UCLIBC 1 138#elif defined(__GLIBC__) || defined(__GNU_LIBRARY__) 139# define V8_LIBC_GLIBC 1 140#else 141# define V8_LIBC_BSD V8_OS_BSD 142#endif 143 144 145// ----------------------------------------------------------------------------- 146// Compiler detection 147// 148// V8_CC_CLANG - Clang 149// V8_CC_GNU - GNU C++ 150// V8_CC_INTEL - Intel C++ 151// V8_CC_MINGW - Minimalist GNU for Windows 152// V8_CC_MINGW32 - Minimalist GNU for Windows (mingw32) 153// V8_CC_MINGW64 - Minimalist GNU for Windows (mingw-w64) 154// V8_CC_MSVC - Microsoft Visual C/C++ 155// 156// C++11 feature detection 157// 158// V8_HAS_CXX11_ALIGNAS - alignas specifier supported 159// V8_HAS_CXX11_ALIGNOF - alignof(type) operator supported 160// V8_HAS_CXX11_STATIC_ASSERT - static_assert() supported 161// V8_HAS_CXX11_DELETE - deleted functions supported 162// V8_HAS_CXX11_FINAL - final marker supported 163// V8_HAS_CXX11_OVERRIDE - override marker supported 164// 165// Compiler-specific feature detection 166// 167// V8_HAS___ALIGNOF - __alignof(type) operator supported 168// V8_HAS___ALIGNOF__ - __alignof__(type) operator supported 169// V8_HAS_ATTRIBUTE_ALIGNED - __attribute__((aligned(n))) supported 170// V8_HAS_ATTRIBUTE_ALWAYS_INLINE - __attribute__((always_inline)) 171// supported 172// V8_HAS_ATTRIBUTE_DEPRECATED - __attribute__((deprecated)) supported 173// V8_HAS_ATTRIBUTE_NOINLINE - __attribute__((noinline)) supported 174// V8_HAS_ATTRIBUTE_UNUSED - __attribute__((unused)) supported 175// V8_HAS_ATTRIBUTE_VISIBILITY - __attribute__((visibility)) supported 176// V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT - __attribute__((warn_unused_result)) 177// supported 178// V8_HAS_BUILTIN_CLZ - __builtin_clz() supported 179// V8_HAS_BUILTIN_CTZ - __builtin_ctz() supported 180// V8_HAS_BUILTIN_EXPECT - __builtin_expect() supported 181// V8_HAS_BUILTIN_POPCOUNT - __builtin_popcount() supported 182// V8_HAS_BUILTIN_SADD_OVERFLOW - __builtin_sadd_overflow() supported 183// V8_HAS_BUILTIN_SSUB_OVERFLOW - __builtin_ssub_overflow() supported 184// V8_HAS_DECLSPEC_ALIGN - __declspec(align(n)) supported 185// V8_HAS_DECLSPEC_DEPRECATED - __declspec(deprecated) supported 186// V8_HAS_DECLSPEC_NOINLINE - __declspec(noinline) supported 187// V8_HAS___FINAL - __final supported in non-C++11 mode 188// V8_HAS___FORCEINLINE - __forceinline supported 189// V8_HAS_SEALED - MSVC style sealed marker supported 190// 191// Note that testing for compilers and/or features must be done using #if 192// not #ifdef. For example, to test for Intel C++ Compiler, use: 193// #if V8_CC_INTEL 194// ... 195// #endif 196 197#if defined(__clang__) 198 199# define V8_CC_CLANG 1 200 201// Clang defines __alignof__ as alias for __alignof 202# define V8_HAS___ALIGNOF 1 203# define V8_HAS___ALIGNOF__ V8_HAS___ALIGNOF 204 205# define V8_HAS_ATTRIBUTE_ALIGNED (__has_attribute(aligned)) 206# define V8_HAS_ATTRIBUTE_ALWAYS_INLINE (__has_attribute(always_inline)) 207# define V8_HAS_ATTRIBUTE_DEPRECATED (__has_attribute(deprecated)) 208# define V8_HAS_ATTRIBUTE_NOINLINE (__has_attribute(noinline)) 209# define V8_HAS_ATTRIBUTE_UNUSED (__has_attribute(unused)) 210# define V8_HAS_ATTRIBUTE_VISIBILITY (__has_attribute(visibility)) 211# define V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT \ 212 (__has_attribute(warn_unused_result)) 213 214# define V8_HAS_BUILTIN_CLZ (__has_builtin(__builtin_clz)) 215# define V8_HAS_BUILTIN_CTZ (__has_builtin(__builtin_ctz)) 216# define V8_HAS_BUILTIN_EXPECT (__has_builtin(__builtin_expect)) 217# define V8_HAS_BUILTIN_POPCOUNT (__has_builtin(__builtin_popcount)) 218# define V8_HAS_BUILTIN_SADD_OVERFLOW (__has_builtin(__builtin_sadd_overflow)) 219# define V8_HAS_BUILTIN_SSUB_OVERFLOW (__has_builtin(__builtin_ssub_overflow)) 220 221# define V8_HAS_CXX11_ALIGNAS (__has_feature(cxx_alignas)) 222# define V8_HAS_CXX11_STATIC_ASSERT (__has_feature(cxx_static_assert)) 223# define V8_HAS_CXX11_DELETE (__has_feature(cxx_deleted_functions)) 224# define V8_HAS_CXX11_FINAL (__has_feature(cxx_override_control)) 225# define V8_HAS_CXX11_OVERRIDE (__has_feature(cxx_override_control)) 226 227#elif defined(__GNUC__) 228 229# define V8_CC_GNU 1 230// Intel C++ also masquerades as GCC 3.2.0 231# define V8_CC_INTEL (defined(__INTEL_COMPILER)) 232# define V8_CC_MINGW32 (defined(__MINGW32__)) 233# define V8_CC_MINGW64 (defined(__MINGW64__)) 234# define V8_CC_MINGW (V8_CC_MINGW32 || V8_CC_MINGW64) 235 236# define V8_HAS___ALIGNOF__ (V8_GNUC_PREREQ(4, 3, 0)) 237 238# define V8_HAS_ATTRIBUTE_ALIGNED (V8_GNUC_PREREQ(2, 95, 0)) 239// always_inline is available in gcc 4.0 but not very reliable until 4.4. 240// Works around "sorry, unimplemented: inlining failed" build errors with 241// older compilers. 242# define V8_HAS_ATTRIBUTE_ALWAYS_INLINE (V8_GNUC_PREREQ(4, 4, 0)) 243# define V8_HAS_ATTRIBUTE_DEPRECATED (V8_GNUC_PREREQ(3, 4, 0)) 244# define V8_HAS_ATTRIBUTE_DEPRECATED_MESSAGE (V8_GNUC_PREREQ(4, 5, 0)) 245# define V8_HAS_ATTRIBUTE_NOINLINE (V8_GNUC_PREREQ(3, 4, 0)) 246# define V8_HAS_ATTRIBUTE_UNUSED (V8_GNUC_PREREQ(2, 95, 0)) 247# define V8_HAS_ATTRIBUTE_VISIBILITY (V8_GNUC_PREREQ(4, 3, 0)) 248# define V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT \ 249 (!V8_CC_INTEL && V8_GNUC_PREREQ(4, 1, 0)) 250 251# define V8_HAS_BUILTIN_CLZ (V8_GNUC_PREREQ(3, 4, 0)) 252# define V8_HAS_BUILTIN_CTZ (V8_GNUC_PREREQ(3, 4, 0)) 253# define V8_HAS_BUILTIN_EXPECT (V8_GNUC_PREREQ(2, 96, 0)) 254# define V8_HAS_BUILTIN_POPCOUNT (V8_GNUC_PREREQ(3, 4, 0)) 255 256// g++ requires -std=c++0x or -std=gnu++0x to support C++11 functionality 257// without warnings (functionality used by the macros below). These modes 258// are detectable by checking whether __GXX_EXPERIMENTAL_CXX0X__ is defined or, 259// more standardly, by checking whether __cplusplus has a C++11 or greater 260// value. Current versions of g++ do not correctly set __cplusplus, so we check 261// both for forward compatibility. 262# if defined(__GXX_EXPERIMENTAL_CXX0X__) || __cplusplus >= 201103L 263# define V8_HAS_CXX11_ALIGNAS (V8_GNUC_PREREQ(4, 8, 0)) 264# define V8_HAS_CXX11_ALIGNOF (V8_GNUC_PREREQ(4, 8, 0)) 265# define V8_HAS_CXX11_STATIC_ASSERT (V8_GNUC_PREREQ(4, 3, 0)) 266# define V8_HAS_CXX11_DELETE (V8_GNUC_PREREQ(4, 4, 0)) 267# define V8_HAS_CXX11_OVERRIDE (V8_GNUC_PREREQ(4, 7, 0)) 268# define V8_HAS_CXX11_FINAL (V8_GNUC_PREREQ(4, 7, 0)) 269# else 270// '__final' is a non-C++11 GCC synonym for 'final', per GCC r176655. 271# define V8_HAS___FINAL (V8_GNUC_PREREQ(4, 7, 0)) 272# endif 273 274#elif defined(_MSC_VER) 275 276# define V8_CC_MSVC 1 277 278# define V8_HAS___ALIGNOF 1 279 280// Override control was added with Visual Studio 2005, but 281// Visual Studio 2010 and earlier spell "final" as "sealed". 282# define V8_HAS_CXX11_FINAL (_MSC_VER >= 1700) 283# define V8_HAS_CXX11_OVERRIDE (_MSC_VER >= 1400) 284# define V8_HAS_SEALED (_MSC_VER >= 1400) 285 286# define V8_HAS_DECLSPEC_ALIGN 1 287# define V8_HAS_DECLSPEC_DEPRECATED (_MSC_VER >= 1300) 288# define V8_HAS_DECLSPEC_NOINLINE 1 289 290# define V8_HAS___FORCEINLINE 1 291 292#endif 293 294 295// ----------------------------------------------------------------------------- 296// Helper macros 297 298// A macro used to make better inlining. Don't bother for debug builds. 299// Use like: 300// V8_INLINE int GetZero() { return 0; } 301#if !defined(DEBUG) && V8_HAS_ATTRIBUTE_ALWAYS_INLINE 302# define V8_INLINE inline __attribute__((always_inline)) 303#elif !defined(DEBUG) && V8_HAS___FORCEINLINE 304# define V8_INLINE __forceinline 305#else 306# define V8_INLINE inline 307#endif 308 309 310// A macro used to tell the compiler to never inline a particular function. 311// Don't bother for debug builds. 312// Use like: 313// V8_NOINLINE int GetMinusOne() { return -1; } 314#if !defined(DEBUG) && V8_HAS_ATTRIBUTE_NOINLINE 315# define V8_NOINLINE __attribute__((noinline)) 316#elif !defined(DEBUG) && V8_HAS_DECLSPEC_NOINLINE 317# define V8_NOINLINE __declspec(noinline) 318#else 319# define V8_NOINLINE /* NOT SUPPORTED */ 320#endif 321 322 323// A macro to mark classes or functions as deprecated. 324#if defined(V8_DEPRECATION_WARNINGS) && V8_HAS_ATTRIBUTE_DEPRECATED_MESSAGE 325# define V8_DEPRECATED(message, declarator) \ 326declarator __attribute__((deprecated(message))) 327#elif defined(V8_DEPRECATION_WARNINGS) && V8_HAS_ATTRIBUTE_DEPRECATED 328# define V8_DEPRECATED(message, declarator) \ 329declarator __attribute__((deprecated)) 330#elif defined(V8_DEPRECATION_WARNINGS) && V8_HAS_DECLSPEC_DEPRECATED 331# define V8_DEPRECATED(message, declarator) __declspec(deprecated) declarator 332#else 333# define V8_DEPRECATED(message, declarator) declarator 334#endif 335 336 337// A macro to provide the compiler with branch prediction information. 338#if V8_HAS_BUILTIN_EXPECT 339# define V8_UNLIKELY(condition) (__builtin_expect(!!(condition), 0)) 340# define V8_LIKELY(condition) (__builtin_expect(!!(condition), 1)) 341#else 342# define V8_UNLIKELY(condition) (condition) 343# define V8_LIKELY(condition) (condition) 344#endif 345 346 347// A macro to specify that a method is deleted from the corresponding class. 348// Any attempt to use the method will always produce an error at compile time 349// when this macro can be implemented (i.e. if the compiler supports C++11). 350// If the current compiler does not support C++11, use of the annotated method 351// will still cause an error, but the error will most likely occur at link time 352// rather than at compile time. As a backstop, method declarations using this 353// macro should be private. 354// Use like: 355// class A { 356// private: 357// A(const A& other) V8_DELETE; 358// A& operator=(const A& other) V8_DELETE; 359// }; 360#if V8_HAS_CXX11_DELETE 361# define V8_DELETE = delete 362#else 363# define V8_DELETE /* NOT SUPPORTED */ 364#endif 365 366 367// This macro allows to specify memory alignment for structs, classes, etc. 368// Use like: 369// class V8_ALIGNED(16) MyClass { ... }; 370// V8_ALIGNED(32) int array[42]; 371#if V8_HAS_CXX11_ALIGNAS 372# define V8_ALIGNED(n) alignas(n) 373#elif V8_HAS_ATTRIBUTE_ALIGNED 374# define V8_ALIGNED(n) __attribute__((aligned(n))) 375#elif V8_HAS_DECLSPEC_ALIGN 376# define V8_ALIGNED(n) __declspec(align(n)) 377#else 378# define V8_ALIGNED(n) /* NOT SUPPORTED */ 379#endif 380 381 382// This macro is similar to V8_ALIGNED(), but takes a type instead of size 383// in bytes. If the compiler does not supports using the alignment of the 384// |type|, it will align according to the |alignment| instead. For example, 385// Visual Studio C++ cannot combine __declspec(align) and __alignof. The 386// |alignment| must be a literal that is used as a kind of worst-case fallback 387// alignment. 388// Use like: 389// struct V8_ALIGNAS(AnotherClass, 16) NewClass { ... }; 390// V8_ALIGNAS(double, 8) int array[100]; 391#if V8_HAS_CXX11_ALIGNAS 392# define V8_ALIGNAS(type, alignment) alignas(type) 393#elif V8_HAS___ALIGNOF__ && V8_HAS_ATTRIBUTE_ALIGNED 394# define V8_ALIGNAS(type, alignment) __attribute__((aligned(__alignof__(type)))) 395#else 396# define V8_ALIGNAS(type, alignment) V8_ALIGNED(alignment) 397#endif 398 399 400// This macro returns alignment in bytes (an integer power of two) required for 401// any instance of the given type, which is either complete type, an array type, 402// or a reference type. 403// Use like: 404// size_t alignment = V8_ALIGNOF(double); 405#if V8_HAS_CXX11_ALIGNOF 406# define V8_ALIGNOF(type) alignof(type) 407#elif V8_HAS___ALIGNOF 408# define V8_ALIGNOF(type) __alignof(type) 409#elif V8_HAS___ALIGNOF__ 410# define V8_ALIGNOF(type) __alignof__(type) 411#else 412// Note that alignment of a type within a struct can be less than the 413// alignment of the type stand-alone (because of ancient ABIs), so this 414// should only be used as a last resort. 415namespace v8 { template <typename T> class AlignOfHelper { char c; T t; }; } 416# define V8_ALIGNOF(type) (sizeof(::v8::AlignOfHelper<type>) - sizeof(type)) 417#endif 418 419#endif // V8CONFIG_H_ 420