v8  4.4.63(io.js3.3.1)
V8 is Google's open source JavaScript engine
v8config.h
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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__ * 100) >=
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_AIX - AIX
71 // V8_OS_WIN - Microsoft Windows
72 
73 #if defined(__ANDROID__)
74 # define V8_OS_ANDROID 1
75 # define V8_OS_LINUX 1
76 # define V8_OS_POSIX 1
77 #elif defined(__APPLE__)
78 # define V8_OS_BSD 1
79 # define V8_OS_MACOSX 1
80 # define V8_OS_POSIX 1
81 #elif defined(__native_client__)
82 # define V8_OS_NACL 1
83 # define V8_OS_POSIX 1
84 #elif defined(__CYGWIN__)
85 # define V8_OS_CYGWIN 1
86 # define V8_OS_POSIX 1
87 #elif defined(__linux__)
88 # define V8_OS_LINUX 1
89 # define V8_OS_POSIX 1
90 #elif defined(__sun)
91 # define V8_OS_POSIX 1
92 # define V8_OS_SOLARIS 1
93 #elif defined(_AIX)
94 #define V8_OS_POSIX 1
95 #define V8_OS_AIX 1
96 #elif defined(__FreeBSD__)
97 # define V8_OS_BSD 1
98 # define V8_OS_FREEBSD 1
99 # define V8_OS_POSIX 1
100 #elif defined(__DragonFly__)
101 # define V8_OS_BSD 1
102 # define V8_OS_DRAGONFLYBSD 1
103 # define V8_OS_POSIX 1
104 #elif defined(__NetBSD__)
105 # define V8_OS_BSD 1
106 # define V8_OS_NETBSD 1
107 # define V8_OS_POSIX 1
108 #elif defined(__OpenBSD__)
109 # define V8_OS_BSD 1
110 # define V8_OS_OPENBSD 1
111 # define V8_OS_POSIX 1
112 #elif defined(__QNXNTO__)
113 # define V8_OS_POSIX 1
114 # define V8_OS_QNX 1
115 #elif defined(_WIN32)
116 # define V8_OS_WIN 1
117 #endif
118 
119 
120 // -----------------------------------------------------------------------------
121 // C library detection
122 //
123 // V8_LIBC_MSVCRT - MSVC libc
124 // V8_LIBC_BIONIC - Bionic libc
125 // V8_LIBC_BSD - BSD libc derivate
126 // V8_LIBC_GLIBC - GNU C library
127 // V8_LIBC_UCLIBC - uClibc
128 //
129 // Note that testing for libc must be done using #if not #ifdef. For example,
130 // to test for the GNU C library, use:
131 // #if V8_LIBC_GLIBC
132 // ...
133 // #endif
134 
135 #if defined (_MSC_VER)
136 # define V8_LIBC_MSVCRT 1
137 #elif defined(__BIONIC__)
138 # define V8_LIBC_BIONIC 1
139 # define V8_LIBC_BSD 1
140 #elif defined(__UCLIBC__)
141 // Must test for UCLIBC before GLIBC, as UCLIBC pretends to be GLIBC.
142 # define V8_LIBC_UCLIBC 1
143 #elif defined(__GLIBC__) || defined(__GNU_LIBRARY__)
144 # define V8_LIBC_GLIBC 1
145 #else
146 # define V8_LIBC_BSD V8_OS_BSD
147 #endif
148 
149 
150 // -----------------------------------------------------------------------------
151 // Compiler detection
152 //
153 // V8_CC_GNU - GCC, or clang in gcc mode
154 // V8_CC_INTEL - Intel C++
155 // V8_CC_MINGW - Minimalist GNU for Windows
156 // V8_CC_MINGW32 - Minimalist GNU for Windows (mingw32)
157 // V8_CC_MINGW64 - Minimalist GNU for Windows (mingw-w64)
158 // V8_CC_MSVC - Microsoft Visual C/C++, or clang in cl.exe mode
159 //
160 // C++11 feature detection
161 //
162 // V8_HAS_CXX11_ALIGNAS - alignas specifier supported
163 // V8_HAS_CXX11_ALIGNOF - alignof(type) operator supported
164 // V8_HAS_CXX11_STATIC_ASSERT - static_assert() supported
165 //
166 // Compiler-specific feature detection
167 //
168 // V8_HAS___ALIGNOF - __alignof(type) operator supported
169 // V8_HAS___ALIGNOF__ - __alignof__(type) operator supported
170 // V8_HAS_ATTRIBUTE_ALIGNED - __attribute__((aligned(n))) supported
171 // V8_HAS_ATTRIBUTE_ALWAYS_INLINE - __attribute__((always_inline))
172 // supported
173 // V8_HAS_ATTRIBUTE_DEPRECATED - __attribute__((deprecated)) supported
174 // V8_HAS_ATTRIBUTE_NOINLINE - __attribute__((noinline)) supported
175 // V8_HAS_ATTRIBUTE_UNUSED - __attribute__((unused)) supported
176 // V8_HAS_ATTRIBUTE_VISIBILITY - __attribute__((visibility)) supported
177 // V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT - __attribute__((warn_unused_result))
178 // supported
179 // V8_HAS_BUILTIN_CLZ - __builtin_clz() supported
180 // V8_HAS_BUILTIN_CTZ - __builtin_ctz() supported
181 // V8_HAS_BUILTIN_EXPECT - __builtin_expect() supported
182 // V8_HAS_BUILTIN_FRAME_ADDRESS - __builtin_frame_address() supported
183 // V8_HAS_BUILTIN_POPCOUNT - __builtin_popcount() supported
184 // V8_HAS_BUILTIN_SADD_OVERFLOW - __builtin_sadd_overflow() supported
185 // V8_HAS_BUILTIN_SSUB_OVERFLOW - __builtin_ssub_overflow() supported
186 // V8_HAS_DECLSPEC_ALIGN - __declspec(align(n)) supported
187 // V8_HAS_DECLSPEC_DEPRECATED - __declspec(deprecated) supported
188 // V8_HAS_DECLSPEC_NOINLINE - __declspec(noinline) supported
189 // V8_HAS_DECLSPEC_SELECTANY - __declspec(selectany) 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 #elif defined(_MSC_VER) // Clang in cl mode.
203 # define V8_CC_MSVC 1
204 #endif
205 
206 // Clang defines __alignof__ as alias for __alignof
207 # define V8_HAS___ALIGNOF 1
208 # define V8_HAS___ALIGNOF__ V8_HAS___ALIGNOF
209 
210 # define V8_HAS_ATTRIBUTE_ALIGNED (__has_attribute(aligned))
211 # define V8_HAS_ATTRIBUTE_ALWAYS_INLINE (__has_attribute(always_inline))
212 # define V8_HAS_ATTRIBUTE_DEPRECATED (__has_attribute(deprecated))
213 # define V8_HAS_ATTRIBUTE_NOINLINE (__has_attribute(noinline))
214 # define V8_HAS_ATTRIBUTE_UNUSED (__has_attribute(unused))
215 # define V8_HAS_ATTRIBUTE_VISIBILITY (__has_attribute(visibility))
216 # define V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT
217  (__has_attribute(warn_unused_result))
218 
219 # define V8_HAS_BUILTIN_CLZ (__has_builtin(__builtin_clz))
220 # define V8_HAS_BUILTIN_CTZ (__has_builtin(__builtin_ctz))
221 # define V8_HAS_BUILTIN_EXPECT (__has_builtin(__builtin_expect))
222 # define V8_HAS_BUILTIN_FRAME_ADDRESS (__has_builtin(__builtin_frame_address))
223 # define V8_HAS_BUILTIN_POPCOUNT (__has_builtin(__builtin_popcount))
224 # define V8_HAS_BUILTIN_SADD_OVERFLOW (__has_builtin(__builtin_sadd_overflow))
225 # define V8_HAS_BUILTIN_SSUB_OVERFLOW (__has_builtin(__builtin_ssub_overflow))
226 
227 # define V8_HAS_CXX11_ALIGNAS (__has_feature(cxx_alignas))
228 # define V8_HAS_CXX11_STATIC_ASSERT (__has_feature(cxx_static_assert))
229 
230 #elif defined(__GNUC__)
231 
232 # define V8_CC_GNU 1
233 // Intel C++ also masquerades as GCC 3.2.0
234 # define V8_CC_INTEL (defined(__INTEL_COMPILER))
235 # define V8_CC_MINGW32 (defined(__MINGW32__))
236 # define V8_CC_MINGW64 (defined(__MINGW64__))
237 # define V8_CC_MINGW (V8_CC_MINGW32 || V8_CC_MINGW64)
238 
239 # define V8_HAS___ALIGNOF__ (V8_GNUC_PREREQ(4, 3, 0))
240 
241 # define V8_HAS_ATTRIBUTE_ALIGNED (V8_GNUC_PREREQ(2, 95, 0))
242 // always_inline is available in gcc 4.0 but not very reliable until 4.4.
243 // Works around "sorry, unimplemented: inlining failed" build errors with
244 // older compilers.
245 # define V8_HAS_ATTRIBUTE_ALWAYS_INLINE (V8_GNUC_PREREQ(4, 4, 0))
246 # define V8_HAS_ATTRIBUTE_DEPRECATED (V8_GNUC_PREREQ(3, 4, 0))
247 # define V8_HAS_ATTRIBUTE_DEPRECATED_MESSAGE (V8_GNUC_PREREQ(4, 5, 0))
248 # define V8_HAS_ATTRIBUTE_NOINLINE (V8_GNUC_PREREQ(3, 4, 0))
249 # define V8_HAS_ATTRIBUTE_UNUSED (V8_GNUC_PREREQ(2, 95, 0))
250 # define V8_HAS_ATTRIBUTE_VISIBILITY (V8_GNUC_PREREQ(4, 3, 0))
251 # define V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT
252  (!V8_CC_INTEL && V8_GNUC_PREREQ(4, 1, 0))
253 
254 # define V8_HAS_BUILTIN_CLZ (V8_GNUC_PREREQ(3, 4, 0))
255 # define V8_HAS_BUILTIN_CTZ (V8_GNUC_PREREQ(3, 4, 0))
256 # define V8_HAS_BUILTIN_EXPECT (V8_GNUC_PREREQ(2, 96, 0))
257 # define V8_HAS_BUILTIN_FRAME_ADDRESS (V8_GNUC_PREREQ(2, 96, 0))
258 # define V8_HAS_BUILTIN_POPCOUNT (V8_GNUC_PREREQ(3, 4, 0))
259 
260 // g++ requires -std=c++0x or -std=gnu++0x to support C++11 functionality
261 // without warnings (functionality used by the macros below). These modes
262 // are detectable by checking whether __GXX_EXPERIMENTAL_CXX0X__ is defined or,
263 // more standardly, by checking whether __cplusplus has a C++11 or greater
264 // value. Current versions of g++ do not correctly set __cplusplus, so we check
265 // both for forward compatibility.
266 # if defined(__GXX_EXPERIMENTAL_CXX0X__) || __cplusplus >= 201103L
267 # define V8_HAS_CXX11_ALIGNAS (V8_GNUC_PREREQ(4, 8, 0))
268 # define V8_HAS_CXX11_ALIGNOF (V8_GNUC_PREREQ(4, 8, 0))
269 # define V8_HAS_CXX11_STATIC_ASSERT (V8_GNUC_PREREQ(4, 3, 0))
270 # endif
271 
272 #elif defined(_MSC_VER)
273 
274 # define V8_CC_MSVC 1
275 
276 # define V8_HAS___ALIGNOF 1
277 
278 # define V8_HAS_DECLSPEC_ALIGN 1
279 # define V8_HAS_DECLSPEC_DEPRECATED 1
280 # define V8_HAS_DECLSPEC_NOINLINE 1
281 # define V8_HAS_DECLSPEC_SELECTANY 1
282 
283 # define V8_HAS___FORCEINLINE 1
284 
285 #endif
286 
287 
288 // -----------------------------------------------------------------------------
289 // Helper macros
290 
291 // A macro used to make better inlining. Don't bother for debug builds.
292 // Use like:
293 // V8_INLINE int GetZero() { return 0; }
294 #if !defined(DEBUG) && V8_HAS_ATTRIBUTE_ALWAYS_INLINE
295 # define V8_INLINE inline __attribute__((always_inline))
296 #elif !defined(DEBUG) && V8_HAS___FORCEINLINE
297 # define V8_INLINE __forceinline
298 #else
299 # define V8_INLINE inline
300 #endif
301 
302 
303 // A macro used to tell the compiler to never inline a particular function.
304 // Don't bother for debug builds.
305 // Use like:
306 // V8_NOINLINE int GetMinusOne() { return -1; }
307 #if !defined(DEBUG) && V8_HAS_ATTRIBUTE_NOINLINE
308 # define V8_NOINLINE __attribute__((noinline))
309 #elif !defined(DEBUG) && V8_HAS_DECLSPEC_NOINLINE
310 # define V8_NOINLINE __declspec(noinline)
311 #else
312 # define V8_NOINLINE /* NOT SUPPORTED */
313 #endif
314 
315 
316 // A macro to mark classes or functions as deprecated.
317 #if defined(V8_DEPRECATION_WARNINGS) && V8_HAS_ATTRIBUTE_DEPRECATED_MESSAGE
318 # define V8_DEPRECATED(message, declarator) declarator
319  __attribute__((deprecated(message)))
320 #elif defined(V8_DEPRECATION_WARNINGS) && V8_HAS_ATTRIBUTE_DEPRECATED
321 # define V8_DEPRECATED(message, declarator) declarator
322  __attribute__((deprecated))
323 #elif defined(V8_DEPRECATION_WARNINGS) && V8_HAS_DECLSPEC_DEPRECATED
324 # define V8_DEPRECATED(message, declarator) __declspec(deprecated) declarator
325 #else
326 # define V8_DEPRECATED(message, declarator) declarator
327 #endif
328 
329 
330 // a macro to make it easier to see what will be deprecated.
331 #define V8_DEPRECATE_SOON(message, declarator) declarator
332 
333 
334 // A macro to provide the compiler with branch prediction information.
335 #if V8_HAS_BUILTIN_EXPECT
336 # define V8_UNLIKELY(condition) (__builtin_expect(!!(condition), 0))
337 # define V8_LIKELY(condition) (__builtin_expect(!!(condition), 1))
338 #else
339 # define V8_UNLIKELY(condition) (condition)
340 # define V8_LIKELY(condition) (condition)
341 #endif
342 
343 
344 // This macro allows to specify memory alignment for structs, classes, etc.
345 // Use like:
346 // class V8_ALIGNED(16) MyClass { ... };
347 // V8_ALIGNED(32) int array[42];
348 #if V8_HAS_CXX11_ALIGNAS
349 # define V8_ALIGNED(n) alignas(n)
350 #elif V8_HAS_ATTRIBUTE_ALIGNED
351 # define V8_ALIGNED(n) __attribute__((aligned(n)))
352 #elif V8_HAS_DECLSPEC_ALIGN
353 # define V8_ALIGNED(n) __declspec(align(n))
354 #else
355 # define V8_ALIGNED(n) /* NOT SUPPORTED */
356 #endif
357 
358 
359 // This macro is similar to V8_ALIGNED(), but takes a type instead of size
360 // in bytes. If the compiler does not supports using the alignment of the
361 // |type|, it will align according to the |alignment| instead. For example,
362 // Visual Studio C++ cannot combine __declspec(align) and __alignof. The
363 // |alignment| must be a literal that is used as a kind of worst-case fallback
364 // alignment.
365 // Use like:
366 // struct V8_ALIGNAS(AnotherClass, 16) NewClass { ... };
367 // V8_ALIGNAS(double, 8) int array[100];
368 #if V8_HAS_CXX11_ALIGNAS
369 # define V8_ALIGNAS(type, alignment) alignas(type)
370 #elif V8_HAS___ALIGNOF__ && V8_HAS_ATTRIBUTE_ALIGNED
371 # define V8_ALIGNAS(type, alignment) __attribute__((aligned(__alignof__(type))))
372 #else
373 # define V8_ALIGNAS(type, alignment) V8_ALIGNED(alignment)
374 #endif
375 
376 
377 // This macro returns alignment in bytes (an integer power of two) required for
378 // any instance of the given type, which is either complete type, an array type,
379 // or a reference type.
380 // Use like:
381 // size_t alignment = V8_ALIGNOF(double);
382 #if V8_HAS_CXX11_ALIGNOF
383 # define V8_ALIGNOF(type) alignof(type)
384 #elif V8_HAS___ALIGNOF
385 # define V8_ALIGNOF(type) __alignof(type)
386 #elif V8_HAS___ALIGNOF__
387 # define V8_ALIGNOF(type) __alignof__(type)
388 #else
389 // Note that alignment of a type within a struct can be less than the
390 // alignment of the type stand-alone (because of ancient ABIs), so this
391 // should only be used as a last resort.
392 namespace v8 { template <typename T> class AlignOfHelper { char c; T t; }; }
393 # define V8_ALIGNOF(type) (sizeof(::v8::AlignOfHelper<type>) - sizeof(type))
394 #endif
395 
396 // Annotate a function indicating the caller must examine the return value.
397 // Use like:
398 // int foo() WARN_UNUSED_RESULT;
399 #if V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT
400 #define V8_WARN_UNUSED_RESULT __attribute__((warn_unused_result))
401 #else
402 #define V8_WARN_UNUSED_RESULT /* NOT SUPPORTED */
403 #endif
404 
405 #endif // V8CONFIG_H_