Home | History | Annotate | Download | only in include
      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 // clang-format off
      9 
     10 // Platform headers for feature detection below.
     11 #if defined(__ANDROID__)
     12 # include <sys/cdefs.h>
     13 #elif defined(__APPLE__)
     14 # include <TargetConditionals.h>
     15 #elif defined(__linux__)
     16 # include <features.h>
     17 #endif
     18 
     19 
     20 // This macro allows to test for the version of the GNU C library (or
     21 // a compatible C library that masquerades as glibc). It evaluates to
     22 // 0 if libc is not GNU libc or compatible.
     23 // Use like:
     24 //  #if V8_GLIBC_PREREQ(2, 3)
     25 //   ...
     26 //  #endif
     27 #if defined(__GLIBC__) && defined(__GLIBC_MINOR__)
     28 # define V8_GLIBC_PREREQ(major, minor)                                    \
     29     ((__GLIBC__ * 100 + __GLIBC_MINOR__) >= ((major) * 100 + (minor)))
     30 #else
     31 # define V8_GLIBC_PREREQ(major, minor) 0
     32 #endif
     33 
     34 
     35 // This macro allows to test for the version of the GNU C++ compiler.
     36 // Note that this also applies to compilers that masquerade as GCC,
     37 // for example clang and the Intel C++ compiler for Linux.
     38 // Use like:
     39 //  #if V8_GNUC_PREREQ(4, 3, 1)
     40 //   ...
     41 //  #endif
     42 #if defined(__GNUC__) && defined(__GNUC_MINOR__) && defined(__GNUC_PATCHLEVEL__)
     43 # define V8_GNUC_PREREQ(major, minor, patchlevel)                         \
     44     ((__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) >=   \
     45      ((major) * 10000 + (minor) * 100 + (patchlevel)))
     46 #elif defined(__GNUC__) && defined(__GNUC_MINOR__)
     47 # define V8_GNUC_PREREQ(major, minor, patchlevel)      \
     48     ((__GNUC__ * 10000 + __GNUC_MINOR__ * 100) >=      \
     49      ((major) * 10000 + (minor) * 100 + (patchlevel)))
     50 #else
     51 # define V8_GNUC_PREREQ(major, minor, patchlevel) 0
     52 #endif
     53 
     54 
     55 
     56 // -----------------------------------------------------------------------------
     57 // Operating system detection
     58 //
     59 //  V8_OS_ANDROID       - Android
     60 //  V8_OS_BSD           - BSDish (Mac OS X, Net/Free/Open/DragonFlyBSD)
     61 //  V8_OS_CYGWIN        - Cygwin
     62 //  V8_OS_DRAGONFLYBSD  - DragonFlyBSD
     63 //  V8_OS_FREEBSD       - FreeBSD
     64 //  V8_OS_LINUX         - Linux
     65 //  V8_OS_MACOSX        - Mac OS X
     66 //  V8_OS_NACL          - Native Client
     67 //  V8_OS_NETBSD        - NetBSD
     68 //  V8_OS_OPENBSD       - OpenBSD
     69 //  V8_OS_POSIX         - POSIX compatible (mostly everything except Windows)
     70 //  V8_OS_QNX           - QNX Neutrino
     71 //  V8_OS_SOLARIS       - Sun Solaris and OpenSolaris
     72 //  V8_OS_AIX           - AIX
     73 //  V8_OS_WIN           - Microsoft Windows
     74 
     75 #if defined(__ANDROID__)
     76 # define V8_OS_ANDROID 1
     77 # define V8_OS_LINUX 1
     78 # define V8_OS_POSIX 1
     79 #elif defined(__APPLE__)
     80 # define V8_OS_BSD 1
     81 # define V8_OS_MACOSX 1
     82 # define V8_OS_POSIX 1
     83 #elif defined(__native_client__)
     84 # define V8_OS_NACL 1
     85 # define V8_OS_POSIX 1
     86 #elif defined(__CYGWIN__)
     87 # define V8_OS_CYGWIN 1
     88 # define V8_OS_POSIX 1
     89 #elif defined(__linux__)
     90 # define V8_OS_LINUX 1
     91 # define V8_OS_POSIX 1
     92 #elif defined(__sun)
     93 # define V8_OS_POSIX 1
     94 # define V8_OS_SOLARIS 1
     95 #elif defined(_AIX)
     96 #define V8_OS_POSIX 1
     97 #define V8_OS_AIX 1
     98 #elif defined(__FreeBSD__)
     99 # define V8_OS_BSD 1
    100 # define V8_OS_FREEBSD 1
    101 # define V8_OS_POSIX 1
    102 #elif defined(__DragonFly__)
    103 # define V8_OS_BSD 1
    104 # define V8_OS_DRAGONFLYBSD 1
    105 # define V8_OS_POSIX 1
    106 #elif defined(__NetBSD__)
    107 # define V8_OS_BSD 1
    108 # define V8_OS_NETBSD 1
    109 # define V8_OS_POSIX 1
    110 #elif defined(__OpenBSD__)
    111 # define V8_OS_BSD 1
    112 # define V8_OS_OPENBSD 1
    113 # define V8_OS_POSIX 1
    114 #elif defined(__QNXNTO__)
    115 # define V8_OS_POSIX 1
    116 # define V8_OS_QNX 1
    117 #elif defined(_WIN32)
    118 # define V8_OS_WIN 1
    119 #endif
    120 
    121 
    122 // -----------------------------------------------------------------------------
    123 // C library detection
    124 //
    125 //  V8_LIBC_MSVCRT  - MSVC libc
    126 //  V8_LIBC_BIONIC  - Bionic libc
    127 //  V8_LIBC_BSD     - BSD libc derivate
    128 //  V8_LIBC_GLIBC   - GNU C library
    129 //  V8_LIBC_UCLIBC  - uClibc
    130 //
    131 // Note that testing for libc must be done using #if not #ifdef. For example,
    132 // to test for the GNU C library, use:
    133 //  #if V8_LIBC_GLIBC
    134 //   ...
    135 //  #endif
    136 
    137 #if defined (_MSC_VER)
    138 # define V8_LIBC_MSVCRT 1
    139 #elif defined(__BIONIC__)
    140 # define V8_LIBC_BIONIC 1
    141 # define V8_LIBC_BSD 1
    142 #elif defined(__UCLIBC__)
    143 // Must test for UCLIBC before GLIBC, as UCLIBC pretends to be GLIBC.
    144 # define V8_LIBC_UCLIBC 1
    145 #elif defined(__GLIBC__) || defined(__GNU_LIBRARY__)
    146 # define V8_LIBC_GLIBC 1
    147 #else
    148 # define V8_LIBC_BSD V8_OS_BSD
    149 #endif
    150 
    151 
    152 // -----------------------------------------------------------------------------
    153 // Compiler detection
    154 //
    155 //  V8_CC_GNU     - GCC, or clang in gcc mode
    156 //  V8_CC_INTEL   - Intel C++
    157 //  V8_CC_MINGW   - Minimalist GNU for Windows
    158 //  V8_CC_MINGW32 - Minimalist GNU for Windows (mingw32)
    159 //  V8_CC_MINGW64 - Minimalist GNU for Windows (mingw-w64)
    160 //  V8_CC_MSVC    - Microsoft Visual C/C++, or clang in cl.exe mode
    161 //
    162 // C++11 feature detection
    163 //
    164 //  V8_HAS_CXX11_ALIGNAS        - alignas specifier supported
    165 //  V8_HAS_CXX11_ALIGNOF        - alignof(type) operator supported
    166 //
    167 // Compiler-specific feature detection
    168 //
    169 //  V8_HAS___ALIGNOF                    - __alignof(type) operator supported
    170 //  V8_HAS___ALIGNOF__                  - __alignof__(type) operator supported
    171 //  V8_HAS_ATTRIBUTE_ALIGNED            - __attribute__((aligned(n))) supported
    172 //  V8_HAS_ATTRIBUTE_ALWAYS_INLINE      - __attribute__((always_inline))
    173 //                                        supported
    174 //  V8_HAS_ATTRIBUTE_DEPRECATED         - __attribute__((deprecated)) supported
    175 //  V8_HAS_ATTRIBUTE_NOINLINE           - __attribute__((noinline)) supported
    176 //  V8_HAS_ATTRIBUTE_NORETURN           - __attribute__((noreturn)) supported
    177 //  V8_HAS_ATTRIBUTE_UNUSED             - __attribute__((unused)) supported
    178 //  V8_HAS_ATTRIBUTE_VISIBILITY         - __attribute__((visibility)) supported
    179 //  V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT - __attribute__((warn_unused_result))
    180 //                                        supported
    181 //  V8_HAS_BUILTIN_CLZ                  - __builtin_clz() supported
    182 //  V8_HAS_BUILTIN_CTZ                  - __builtin_ctz() supported
    183 //  V8_HAS_BUILTIN_EXPECT               - __builtin_expect() supported
    184 //  V8_HAS_BUILTIN_FRAME_ADDRESS        - __builtin_frame_address() supported
    185 //  V8_HAS_BUILTIN_POPCOUNT             - __builtin_popcount() supported
    186 //  V8_HAS_BUILTIN_SADD_OVERFLOW        - __builtin_sadd_overflow() supported
    187 //  V8_HAS_BUILTIN_SSUB_OVERFLOW        - __builtin_ssub_overflow() supported
    188 //  V8_HAS_BUILTIN_UADD_OVERFLOW        - __builtin_uadd_overflow() supported
    189 //  V8_HAS_DECLSPEC_ALIGN               - __declspec(align(n)) supported
    190 //  V8_HAS_DECLSPEC_DEPRECATED          - __declspec(deprecated) supported
    191 //  V8_HAS_DECLSPEC_NOINLINE            - __declspec(noinline) supported
    192 //  V8_HAS_DECLSPEC_SELECTANY           - __declspec(selectany) supported
    193 //  V8_HAS_DECLSPEC_NORETURN            - __declspec(noreturn) supported
    194 //  V8_HAS___FORCEINLINE                - __forceinline supported
    195 //
    196 // Note that testing for compilers and/or features must be done using #if
    197 // not #ifdef. For example, to test for Intel C++ Compiler, use:
    198 //  #if V8_CC_INTEL
    199 //   ...
    200 //  #endif
    201 
    202 #if defined(__clang__)
    203 
    204 #if defined(__GNUC__)  // Clang in gcc mode.
    205 # define V8_CC_GNU 1
    206 #endif
    207 
    208 // Clang defines __alignof__ as alias for __alignof
    209 # define V8_HAS___ALIGNOF 1
    210 # define V8_HAS___ALIGNOF__ V8_HAS___ALIGNOF
    211 
    212 # define V8_HAS_ATTRIBUTE_ALIGNED (__has_attribute(aligned))
    213 # define V8_HAS_ATTRIBUTE_ALWAYS_INLINE (__has_attribute(always_inline))
    214 # define V8_HAS_ATTRIBUTE_DEPRECATED (__has_attribute(deprecated))
    215 # define V8_HAS_ATTRIBUTE_NOINLINE (__has_attribute(noinline))
    216 # define V8_HAS_ATTRIBUTE_NORETURN (__has_attribute(noreturn))
    217 # define V8_HAS_ATTRIBUTE_UNUSED (__has_attribute(unused))
    218 # define V8_HAS_ATTRIBUTE_VISIBILITY (__has_attribute(visibility))
    219 # define V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT \
    220     (__has_attribute(warn_unused_result))
    221 
    222 # define V8_HAS_BUILTIN_CLZ (__has_builtin(__builtin_clz))
    223 # define V8_HAS_BUILTIN_CTZ (__has_builtin(__builtin_ctz))
    224 # define V8_HAS_BUILTIN_EXPECT (__has_builtin(__builtin_expect))
    225 # define V8_HAS_BUILTIN_FRAME_ADDRESS (__has_builtin(__builtin_frame_address))
    226 # define V8_HAS_BUILTIN_POPCOUNT (__has_builtin(__builtin_popcount))
    227 # define V8_HAS_BUILTIN_SADD_OVERFLOW (__has_builtin(__builtin_sadd_overflow))
    228 # define V8_HAS_BUILTIN_SSUB_OVERFLOW (__has_builtin(__builtin_ssub_overflow))
    229 # define V8_HAS_BUILTIN_UADD_OVERFLOW (__has_builtin(__builtin_uadd_overflow))
    230 
    231 # define V8_HAS_CXX11_ALIGNAS (__has_feature(cxx_alignas))
    232 
    233 #elif defined(__GNUC__)
    234 
    235 # define V8_CC_GNU 1
    236 # if defined(__INTEL_COMPILER)  // Intel C++ also masquerades as GCC 3.2.0
    237 #  define V8_CC_INTEL 1
    238 # endif
    239 # if defined(__MINGW32__)
    240 #  define V8_CC_MINGW32 1
    241 # endif
    242 # if defined(__MINGW64__)
    243 #  define V8_CC_MINGW64 1
    244 # endif
    245 # define V8_CC_MINGW (V8_CC_MINGW32 || V8_CC_MINGW64)
    246 
    247 # define V8_HAS___ALIGNOF__ (V8_GNUC_PREREQ(4, 3, 0))
    248 
    249 # define V8_HAS_ATTRIBUTE_ALIGNED (V8_GNUC_PREREQ(2, 95, 0))
    250 // always_inline is available in gcc 4.0 but not very reliable until 4.4.
    251 // Works around "sorry, unimplemented: inlining failed" build errors with
    252 // older compilers.
    253 # define V8_HAS_ATTRIBUTE_ALWAYS_INLINE (V8_GNUC_PREREQ(4, 4, 0))
    254 # define V8_HAS_ATTRIBUTE_DEPRECATED (V8_GNUC_PREREQ(3, 4, 0))
    255 # define V8_HAS_ATTRIBUTE_DEPRECATED_MESSAGE (V8_GNUC_PREREQ(4, 5, 0))
    256 # define V8_HAS_ATTRIBUTE_NOINLINE (V8_GNUC_PREREQ(3, 4, 0))
    257 # define V8_HAS_ATTRIBUTE_NORETURN (V8_GNUC_PREREQ(2, 5, 0))
    258 # define V8_HAS_ATTRIBUTE_UNUSED (V8_GNUC_PREREQ(2, 95, 0))
    259 # define V8_HAS_ATTRIBUTE_VISIBILITY (V8_GNUC_PREREQ(4, 3, 0))
    260 # define V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT \
    261     (!V8_CC_INTEL && V8_GNUC_PREREQ(4, 1, 0))
    262 
    263 # define V8_HAS_BUILTIN_CLZ (V8_GNUC_PREREQ(3, 4, 0))
    264 # define V8_HAS_BUILTIN_CTZ (V8_GNUC_PREREQ(3, 4, 0))
    265 # define V8_HAS_BUILTIN_EXPECT (V8_GNUC_PREREQ(2, 96, 0))
    266 # define V8_HAS_BUILTIN_FRAME_ADDRESS (V8_GNUC_PREREQ(2, 96, 0))
    267 # define V8_HAS_BUILTIN_POPCOUNT (V8_GNUC_PREREQ(3, 4, 0))
    268 
    269 // g++ requires -std=c++0x or -std=gnu++0x to support C++11 functionality
    270 // without warnings (functionality used by the macros below).  These modes
    271 // are detectable by checking whether __GXX_EXPERIMENTAL_CXX0X__ is defined or,
    272 // more standardly, by checking whether __cplusplus has a C++11 or greater
    273 // value. Current versions of g++ do not correctly set __cplusplus, so we check
    274 // both for forward compatibility.
    275 # if defined(__GXX_EXPERIMENTAL_CXX0X__) || __cplusplus >= 201103L
    276 #  define V8_HAS_CXX11_ALIGNAS (V8_GNUC_PREREQ(4, 8, 0))
    277 #  define V8_HAS_CXX11_ALIGNOF (V8_GNUC_PREREQ(4, 8, 0))
    278 # endif
    279 #endif
    280 
    281 #if defined(_MSC_VER)
    282 # define V8_CC_MSVC 1
    283 # define V8_HAS___ALIGNOF 1
    284 
    285 # define V8_HAS_DECLSPEC_ALIGN 1
    286 # define V8_HAS_DECLSPEC_DEPRECATED 1
    287 # define V8_HAS_DECLSPEC_NOINLINE 1
    288 # define V8_HAS_DECLSPEC_SELECTANY 1
    289 # define V8_HAS_DECLSPEC_NORETURN 1
    290 
    291 # define V8_HAS___FORCEINLINE 1
    292 
    293 #endif
    294 
    295 
    296 // -----------------------------------------------------------------------------
    297 // Helper macros
    298 
    299 // A macro used to make better inlining. Don't bother for debug builds.
    300 // Use like:
    301 //   V8_INLINE int GetZero() { return 0; }
    302 #if !defined(DEBUG) && V8_HAS_ATTRIBUTE_ALWAYS_INLINE
    303 # define V8_INLINE inline __attribute__((always_inline))
    304 #elif !defined(DEBUG) && V8_HAS___FORCEINLINE
    305 # define V8_INLINE __forceinline
    306 #else
    307 # define V8_INLINE inline
    308 #endif
    309 
    310 
    311 // A macro used to tell the compiler to never inline a particular function.
    312 // Don't bother for debug builds.
    313 // Use like:
    314 //   V8_NOINLINE int GetMinusOne() { return -1; }
    315 #if !defined(DEBUG) && V8_HAS_ATTRIBUTE_NOINLINE
    316 # define V8_NOINLINE __attribute__((noinline))
    317 #elif !defined(DEBUG) && V8_HAS_DECLSPEC_NOINLINE
    318 # define V8_NOINLINE __declspec(noinline)
    319 #else
    320 # define V8_NOINLINE /* NOT SUPPORTED */
    321 #endif
    322 
    323 
    324 // A macro used to tell the compiler that a particular function never returns.
    325 // Use like:
    326 //   V8_NORETURN void MyAbort() { abort(); }
    327 #if V8_HAS_ATTRIBUTE_NORETURN
    328 # define V8_NORETURN __attribute__((noreturn))
    329 #elif HAS_DECLSPEC_NORETURN
    330 # define V8_NORETURN __declspec(noreturn)
    331 #else
    332 # define V8_NORETURN /* NOT SUPPORTED */
    333 #endif
    334 
    335 
    336 // A macro (V8_DEPRECATED) to mark classes or functions as deprecated.
    337 #if defined(V8_DEPRECATION_WARNINGS) && V8_HAS_ATTRIBUTE_DEPRECATED_MESSAGE
    338 #define V8_DEPRECATED(message, declarator) \
    339   declarator __attribute__((deprecated(message)))
    340 #elif defined(V8_DEPRECATION_WARNINGS) && V8_HAS_ATTRIBUTE_DEPRECATED
    341 #define V8_DEPRECATED(message, declarator) \
    342   declarator __attribute__((deprecated))
    343 #elif defined(V8_DEPRECATION_WARNINGS) && V8_HAS_DECLSPEC_DEPRECATED
    344 #define V8_DEPRECATED(message, declarator) __declspec(deprecated) declarator
    345 #else
    346 #define V8_DEPRECATED(message, declarator) declarator
    347 #endif
    348 
    349 
    350 // A macro (V8_DEPRECATE_SOON) to make it easier to see what will be deprecated.
    351 #if defined(V8_IMMINENT_DEPRECATION_WARNINGS) && \
    352     V8_HAS_ATTRIBUTE_DEPRECATED_MESSAGE
    353 #define V8_DEPRECATE_SOON(message, declarator) \
    354   declarator __attribute__((deprecated(message)))
    355 #elif defined(V8_IMMINENT_DEPRECATION_WARNINGS) && V8_HAS_ATTRIBUTE_DEPRECATED
    356 #define V8_DEPRECATE_SOON(message, declarator) \
    357   declarator __attribute__((deprecated))
    358 #elif defined(V8_IMMINENT_DEPRECATION_WARNINGS) && V8_HAS_DECLSPEC_DEPRECATED
    359 #define V8_DEPRECATE_SOON(message, declarator) __declspec(deprecated) declarator
    360 #else
    361 #define V8_DEPRECATE_SOON(message, declarator) declarator
    362 #endif
    363 
    364 
    365 // A macro to provide the compiler with branch prediction information.
    366 #if V8_HAS_BUILTIN_EXPECT
    367 # define V8_UNLIKELY(condition) (__builtin_expect(!!(condition), 0))
    368 # define V8_LIKELY(condition) (__builtin_expect(!!(condition), 1))
    369 #else
    370 # define V8_UNLIKELY(condition) (condition)
    371 # define V8_LIKELY(condition) (condition)
    372 #endif
    373 
    374 
    375 // This macro allows to specify memory alignment for structs, classes, etc.
    376 // Use like:
    377 //   class V8_ALIGNED(16) MyClass { ... };
    378 //   V8_ALIGNED(32) int array[42];
    379 #if V8_HAS_CXX11_ALIGNAS
    380 # define V8_ALIGNED(n) alignas(n)
    381 #elif V8_HAS_ATTRIBUTE_ALIGNED
    382 # define V8_ALIGNED(n) __attribute__((aligned(n)))
    383 #elif V8_HAS_DECLSPEC_ALIGN
    384 # define V8_ALIGNED(n) __declspec(align(n))
    385 #else
    386 # define V8_ALIGNED(n) /* NOT SUPPORTED */
    387 #endif
    388 
    389 
    390 // This macro is similar to V8_ALIGNED(), but takes a type instead of size
    391 // in bytes. If the compiler does not supports using the alignment of the
    392 // |type|, it will align according to the |alignment| instead. For example,
    393 // Visual Studio C++ cannot combine __declspec(align) and __alignof. The
    394 // |alignment| must be a literal that is used as a kind of worst-case fallback
    395 // alignment.
    396 // Use like:
    397 //   struct V8_ALIGNAS(AnotherClass, 16) NewClass { ... };
    398 //   V8_ALIGNAS(double, 8) int array[100];
    399 #if V8_HAS_CXX11_ALIGNAS
    400 # define V8_ALIGNAS(type, alignment) alignas(type)
    401 #elif V8_HAS___ALIGNOF__ && V8_HAS_ATTRIBUTE_ALIGNED
    402 # define V8_ALIGNAS(type, alignment) __attribute__((aligned(__alignof__(type))))
    403 #else
    404 # define V8_ALIGNAS(type, alignment) V8_ALIGNED(alignment)
    405 #endif
    406 
    407 
    408 // This macro returns alignment in bytes (an integer power of two) required for
    409 // any instance of the given type, which is either complete type, an array type,
    410 // or a reference type.
    411 // Use like:
    412 //   size_t alignment = V8_ALIGNOF(double);
    413 #if V8_HAS_CXX11_ALIGNOF
    414 # define V8_ALIGNOF(type) alignof(type)
    415 #elif V8_HAS___ALIGNOF
    416 # define V8_ALIGNOF(type) __alignof(type)
    417 #elif V8_HAS___ALIGNOF__
    418 # define V8_ALIGNOF(type) __alignof__(type)
    419 #else
    420 // Note that alignment of a type within a struct can be less than the
    421 // alignment of the type stand-alone (because of ancient ABIs), so this
    422 // should only be used as a last resort.
    423 namespace v8 { template <typename T> class AlignOfHelper { char c; T t; }; }
    424 # define V8_ALIGNOF(type) (sizeof(::v8::AlignOfHelper<type>) - sizeof(type))
    425 #endif
    426 
    427 // Annotate a function indicating the caller must examine the return value.
    428 // Use like:
    429 //   int foo() WARN_UNUSED_RESULT;
    430 #if V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT
    431 #define V8_WARN_UNUSED_RESULT __attribute__((warn_unused_result))
    432 #else
    433 #define V8_WARN_UNUSED_RESULT /* NOT SUPPORTED */
    434 #endif
    435 
    436 // clang-format on
    437 
    438 #endif  // V8CONFIG_H_
    439