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