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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#ifdef V8_GN_HEADER
9#if __cplusplus >= 201703L && !__has_include("v8-gn.h")
10#error Missing v8-gn.h. The configuration for v8 is missing from the include \
11path. Add it with -I<path> to the command line
12#endif
13#include "v8-gn.h" // NOLINT(build/include_directory)
14#endif
15
16#include <memory>
17// clang-format off
18
19// Platform headers for feature detection below.
20#if defined(__ANDROID__)
21# include <sys/cdefs.h>
22#elif defined(__APPLE__)
23# include <TargetConditionals.h>
24#elif defined(__linux__)
25# include <features.h>
26#endif
27
28
29// This macro allows to test for the version of the GNU C library (or
30// a compatible C library that masquerades as glibc). It evaluates to
31// 0 if libc is not GNU libc or compatible.
32// Use like:
33// #if V8_GLIBC_PREREQ(2, 3)
34// ...
35// #endif
36#if defined(__GLIBC__) && defined(__GLIBC_MINOR__)
37# define V8_GLIBC_PREREQ(major, minor) \
38 ((__GLIBC__ * 100 + __GLIBC_MINOR__) >= ((major) * 100 + (minor)))
39#else
40# define V8_GLIBC_PREREQ(major, minor) 0
41#endif
42
43
44// This macro allows to test for the version of the GNU C++ compiler.
45// Note that this also applies to compilers that masquerade as GCC,
46// for example clang and the Intel C++ compiler for Linux.
47// Use like:
48// #if V8_GNUC_PREREQ(4, 3, 1)
49// ...
50// #endif
51#if defined(__GNUC__) && defined(__GNUC_MINOR__) && defined(__GNUC_PATCHLEVEL__)
52# define V8_GNUC_PREREQ(major, minor, patchlevel) \
53 ((__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) >= \
54 ((major) * 10000 + (minor) * 100 + (patchlevel)))
55#elif defined(__GNUC__) && defined(__GNUC_MINOR__)
56# define V8_GNUC_PREREQ(major, minor, patchlevel) \
57 ((__GNUC__ * 10000 + __GNUC_MINOR__ * 100) >= \
58 ((major) * 10000 + (minor) * 100 + (patchlevel)))
59#else
60# define V8_GNUC_PREREQ(major, minor, patchlevel) 0
61#endif
62
63
64
65// -----------------------------------------------------------------------------
66// Operating system detection (host)
67//
68// V8_OS_ANDROID - Android
69// V8_OS_BSD - BSDish (macOS, Net/Free/Open/DragonFlyBSD)
70// V8_OS_CYGWIN - Cygwin
71// V8_OS_DRAGONFLYBSD - DragonFlyBSD
72// V8_OS_FREEBSD - FreeBSD
73// V8_OS_FUCHSIA - Fuchsia
74// V8_OS_LINUX - Linux (Android, ChromeOS, Linux, ...)
75// V8_OS_DARWIN - Darwin (macOS, iOS)
76// V8_OS_MACOS - macOS
77// V8_OS_IOS - iOS
78// V8_OS_NETBSD - NetBSD
79// V8_OS_OPENBSD - OpenBSD
80// V8_OS_POSIX - POSIX compatible (mostly everything except Windows)
81// V8_OS_QNX - QNX Neutrino
82// V8_OS_SOLARIS - Sun Solaris and OpenSolaris
83// V8_OS_STARBOARD - Starboard (platform abstraction for Cobalt)
84// V8_OS_AIX - AIX
85// V8_OS_WIN - Microsoft Windows
86
87#if defined(__ANDROID__)
88# define V8_OS_ANDROID 1
89# define V8_OS_LINUX 1
90# define V8_OS_POSIX 1
91# define V8_OS_STRING "android"
92
93#elif defined(__APPLE__)
94# define V8_OS_POSIX 1
95# define V8_OS_BSD 1
96# define V8_OS_DARWIN 1
97# if defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE
98# define V8_OS_IOS 1
99# define V8_OS_STRING "ios"
100# else
101# define V8_OS_MACOS 1
102# define V8_OS_STRING "macos"
103# endif // defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE
104
105#elif defined(__CYGWIN__)
106# define V8_OS_CYGWIN 1
107# define V8_OS_POSIX 1
108# define V8_OS_STRING "cygwin"
109
110#elif defined(__linux__)
111# define V8_OS_LINUX 1
112# define V8_OS_POSIX 1
113# define V8_OS_STRING "linux"
114
115#elif defined(__sun)
116# define V8_OS_POSIX 1
117# define V8_OS_SOLARIS 1
118# define V8_OS_STRING "sun"
119
120#elif defined(STARBOARD)
121# define V8_OS_STARBOARD 1
122# define V8_OS_STRING "starboard"
123
124#elif defined(_AIX)
125# define V8_OS_POSIX 1
126# define V8_OS_AIX 1
127# define V8_OS_STRING "aix"
128
129#elif defined(__FreeBSD__)
130# define V8_OS_BSD 1
131# define V8_OS_FREEBSD 1
132# define V8_OS_POSIX 1
133# define V8_OS_STRING "freebsd"
134
135#elif defined(__Fuchsia__)
136# define V8_OS_FUCHSIA 1
137# define V8_OS_POSIX 1
138# define V8_OS_STRING "fuchsia"
139
140#elif defined(__DragonFly__)
141# define V8_OS_BSD 1
142# define V8_OS_DRAGONFLYBSD 1
143# define V8_OS_POSIX 1
144# define V8_OS_STRING "dragonflybsd"
145
146#elif defined(__NetBSD__)
147# define V8_OS_BSD 1
148# define V8_OS_NETBSD 1
149# define V8_OS_POSIX 1
150# define V8_OS_STRING "netbsd"
151
152#elif defined(__OpenBSD__)
153# define V8_OS_BSD 1
154# define V8_OS_OPENBSD 1
155# define V8_OS_POSIX 1
156# define V8_OS_STRING "openbsd"
157
158#elif defined(__QNXNTO__)
159# define V8_OS_POSIX 1
160# define V8_OS_QNX 1
161# define V8_OS_STRING "qnx"
162
163#elif defined(_WIN32)
164# define V8_OS_WIN 1
165# define V8_OS_STRING "windows"
166#endif
167
168// -----------------------------------------------------------------------------
169// Operating system detection (target)
170//
171// V8_TARGET_OS_ANDROID
172// V8_TARGET_OS_FUCHSIA
173// V8_TARGET_OS_IOS
174// V8_TARGET_OS_LINUX
175// V8_TARGET_OS_MACOS
176// V8_TARGET_OS_WIN
177// V8_TARGET_OS_CHROMEOS
178//
179// If not set explicitly, these fall back to corresponding V8_OS_ values.
180
181#ifdef V8_HAVE_TARGET_OS
182
183// The target OS is provided, just check that at least one known value is set.
184# if !defined(V8_TARGET_OS_ANDROID) \
185 && !defined(V8_TARGET_OS_FUCHSIA) \
186 && !defined(V8_TARGET_OS_IOS) \
187 && !defined(V8_TARGET_OS_LINUX) \
188 && !defined(V8_TARGET_OS_MACOS) \
189 && !defined(V8_TARGET_OS_WIN) \
190 && !defined(V8_TARGET_OS_CHROMEOS)
191# error No known target OS defined.
192# endif
193
194#else // V8_HAVE_TARGET_OS
195
196# if defined(V8_TARGET_OS_ANDROID) \
197 || defined(V8_TARGET_OS_FUCHSIA) \
198 || defined(V8_TARGET_OS_IOS) \
199 || defined(V8_TARGET_OS_LINUX) \
200 || defined(V8_TARGET_OS_MACOS) \
201 || defined(V8_TARGET_OS_WIN) \
202 || defined(V8_TARGET_OS_CHROMEOS)
203# error A target OS is defined but V8_HAVE_TARGET_OS is unset.
204# endif
205
206// Fall back to the detected host OS.
207#ifdef V8_OS_ANDROID
208# define V8_TARGET_OS_ANDROID
209#endif
210
211#ifdef V8_OS_FUCHSIA
212# define V8_TARGET_OS_FUCHSIA
213#endif
214
215#ifdef V8_OS_IOS
216# define V8_TARGET_OS_IOS
217#endif
218
219#ifdef V8_OS_LINUX
220# define V8_TARGET_OS_LINUX
221#endif
222
223#ifdef V8_OS_MACOS
224# define V8_TARGET_OS_MACOS
225#endif
226
227#ifdef V8_OS_WIN
228# define V8_TARGET_OS_WIN
229#endif
230
231#endif // V8_HAVE_TARGET_OS
232
233#if defined(V8_TARGET_OS_ANDROID)
234# define V8_TARGET_OS_STRING "android"
235#elif defined(V8_TARGET_OS_FUCHSIA)
236# define V8_TARGET_OS_STRING "fuchsia"
237#elif defined(V8_TARGET_OS_IOS)
238# define V8_TARGET_OS_STRING "ios"
239#elif defined(V8_TARGET_OS_LINUX)
240# define V8_TARGET_OS_STRING "linux"
241#elif defined(V8_TARGET_OS_MACOS)
242# define V8_TARGET_OS_STRING "macos"
243#elif defined(V8_TARGET_OS_WINDOWS)
244# define V8_TARGET_OS_STRING "windows"
245#else
246# define V8_TARGET_OS_STRING "unknown"
247#endif
248
249// -----------------------------------------------------------------------------
250// C library detection
251//
252// V8_LIBC_MSVCRT - MSVC libc
253// V8_LIBC_BIONIC - Bionic libc
254// V8_LIBC_BSD - BSD libc derivate
255// V8_LIBC_GLIBC - GNU C library
256// V8_LIBC_UCLIBC - uClibc
257//
258// Note that testing for libc must be done using #if not #ifdef. For example,
259// to test for the GNU C library, use:
260// #if V8_LIBC_GLIBC
261// ...
262// #endif
263
264#if defined (_MSC_VER)
265# define V8_LIBC_MSVCRT 1
266#elif defined(__BIONIC__)
267# define V8_LIBC_BIONIC 1
268# define V8_LIBC_BSD 1
269#elif defined(__UCLIBC__)
270// Must test for UCLIBC before GLIBC, as UCLIBC pretends to be GLIBC.
271# define V8_LIBC_UCLIBC 1
272#elif defined(__GLIBC__) || defined(__GNU_LIBRARY__)
273# define V8_LIBC_GLIBC 1
274#else
275# define V8_LIBC_BSD V8_OS_BSD
276#endif
277
278
279// -----------------------------------------------------------------------------
280// Compiler detection
281//
282// V8_CC_GNU - GCC, or clang in gcc mode
283// V8_CC_INTEL - Intel C++
284// V8_CC_MINGW - Minimalist GNU for Windows
285// V8_CC_MINGW32 - Minimalist GNU for Windows (mingw32)
286// V8_CC_MINGW64 - Minimalist GNU for Windows (mingw-w64)
287// V8_CC_MSVC - Microsoft Visual C/C++, or clang in cl.exe mode
288//
289// C++11 feature detection
290//
291// Compiler-specific feature detection
292//
293// V8_HAS_ATTRIBUTE_ALWAYS_INLINE - __attribute__((always_inline))
294// supported
295// V8_HAS_ATTRIBUTE_CONSTINIT - __attribute__((require_constant_
296// initialization))
297// supported
298// V8_HAS_ATTRIBUTE_NONNULL - __attribute__((nonnull)) supported
299// V8_HAS_ATTRIBUTE_NOINLINE - __attribute__((noinline)) supported
300// V8_HAS_ATTRIBUTE_UNUSED - __attribute__((unused)) supported
301// V8_HAS_ATTRIBUTE_USED - __attribute__((used)) supported
302// V8_HAS_ATTRIBUTE_RETAIN - __attribute__((retain)) supported
303// V8_HAS_ATTRIBUTE_VISIBILITY - __attribute__((visibility)) supported
304// V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT - __attribute__((warn_unused_result))
305// supported
306// V8_HAS_CPP_ATTRIBUTE_NODISCARD - [[nodiscard]] supported
307// V8_HAS_CPP_ATTRIBUTE_NO_UNIQUE_ADDRESS
308// - [[no_unique_address]] supported
309// V8_HAS_BUILTIN_ADD_OVERFLOW - __builtin_add_overflow() supported
310// V8_HAS_BUILTIN_BIT_CAST - __builtin_bit_cast() supported
311// V8_HAS_BUILTIN_BSWAP16 - __builtin_bswap16() supported
312// V8_HAS_BUILTIN_BSWAP32 - __builtin_bswap32() supported
313// V8_HAS_BUILTIN_BSWAP64 - __builtin_bswap64() supported
314// V8_HAS_BUILTIN_CLZ - __builtin_clz() supported
315// V8_HAS_BUILTIN_CTZ - __builtin_ctz() supported
316// V8_HAS_BUILTIN_EXPECT - __builtin_expect() supported
317// V8_HAS_BUILTIN_FRAME_ADDRESS - __builtin_frame_address() supported
318// V8_HAS_BUILTIN_MUL_OVERFLOW - __builtin_mul_overflow() supported
319// V8_HAS_BUILTIN_POPCOUNT - __builtin_popcount() supported
320// V8_HAS_BUILTIN_SADD_OVERFLOW - __builtin_sadd_overflow() supported
321// V8_HAS_BUILTIN_SMUL_OVERFLOW - __builtin_smul_overflow() supported
322// V8_HAS_BUILTIN_SSUB_OVERFLOW - __builtin_ssub_overflow() supported
323// V8_HAS_BUILTIN_SUB_OVERFLOW - __builtin_sub_overflow() supported
324// V8_HAS_BUILTIN_UADD_OVERFLOW - __builtin_uadd_overflow() supported
325// V8_HAS_COMPUTED_GOTO - computed goto/labels as values
326// supported
327// V8_HAS_DECLSPEC_NOINLINE - __declspec(noinline) supported
328// V8_HAS_DECLSPEC_SELECTANY - __declspec(selectany) supported
329// V8_HAS___FORCEINLINE - __forceinline supported
330//
331// Note that testing for compilers and/or features must be done using #if
332// not #ifdef. For example, to test for Intel C++ Compiler, use:
333// #if V8_CC_INTEL
334// ...
335// #endif
336
337#if defined(__has_cpp_attribute)
338#define V8_HAS_CPP_ATTRIBUTE(FEATURE) __has_cpp_attribute(FEATURE)
339#else
340#define V8_HAS_CPP_ATTRIBUTE(FEATURE) 0
341#endif
342
343#if defined(__clang__)
344
345#if defined(__GNUC__) // Clang in gcc mode.
346# define V8_CC_GNU 1
347#endif
348
349# define V8_HAS_ATTRIBUTE_ALWAYS_INLINE (__has_attribute(always_inline))
350# define V8_HAS_ATTRIBUTE_CONSTINIT \
351 (__has_attribute(require_constant_initialization))
352# define V8_HAS_ATTRIBUTE_CONST (__has_attribute(const))
353# define V8_HAS_ATTRIBUTE_NONNULL (__has_attribute(nonnull))
354# define V8_HAS_ATTRIBUTE_NOINLINE (__has_attribute(noinline))
355# define V8_HAS_ATTRIBUTE_UNUSED (__has_attribute(unused))
356# define V8_HAS_ATTRIBUTE_USED (__has_attribute(used))
357# define V8_HAS_ATTRIBUTE_RETAIN (__has_attribute(retain))
358// Support for the "preserve_most" attribute is limited:
359// - 32-bit platforms do not implement it,
360// - component builds fail because _dl_runtime_resolve clobbers registers,
361// - we see crashes on arm64 on Windows (https://crbug.com/1409934), which can
362// hopefully be fixed in the future.
363// Additionally, the initial implementation in clang <= 16 overwrote the return
364// register(s) in the epilogue of a preserve_most function, so we only use
365// preserve_most in clang >= 17 (see https://reviews.llvm.org/D143425).
366#if (defined(_M_X64) || defined(__x86_64__) /* x64 (everywhere) */ \
367 || ((defined(__AARCH64EL__) || defined(_M_ARM64)) /* arm64, but ... */ \
368 && !defined(_WIN32))) /* not on windows */ \
369 && !defined(COMPONENT_BUILD) /* no component build */\
370 && __clang_major__ >= 17 /* clang >= 17 */
371# define V8_HAS_ATTRIBUTE_PRESERVE_MOST (__has_attribute(preserve_most))
372#endif
373# define V8_HAS_ATTRIBUTE_VISIBILITY (__has_attribute(visibility))
374# define V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT \
375 (__has_attribute(warn_unused_result))
376# define V8_HAS_ATTRIBUTE_WEAK (__has_attribute(weak))
377
378# define V8_HAS_CPP_ATTRIBUTE_NODISCARD (V8_HAS_CPP_ATTRIBUTE(nodiscard))
379# define V8_HAS_CPP_ATTRIBUTE_NO_UNIQUE_ADDRESS \
380 (V8_HAS_CPP_ATTRIBUTE(no_unique_address))
381
382# define V8_HAS_BUILTIN_ADD_OVERFLOW (__has_builtin(__builtin_add_overflow))
383# define V8_HAS_BUILTIN_ASSUME (__has_builtin(__builtin_assume))
384# define V8_HAS_BUILTIN_ASSUME_ALIGNED (__has_builtin(__builtin_assume_aligned))
385# define V8_HAS_BUILTIN_BIT_CAST (__has_builtin(__builtin_bit_cast))
386# define V8_HAS_BUILTIN_BSWAP16 (__has_builtin(__builtin_bswap16))
387# define V8_HAS_BUILTIN_BSWAP32 (__has_builtin(__builtin_bswap32))
388# define V8_HAS_BUILTIN_BSWAP64 (__has_builtin(__builtin_bswap64))
389# define V8_HAS_BUILTIN_CLZ (__has_builtin(__builtin_clz))
390# define V8_HAS_BUILTIN_CTZ (__has_builtin(__builtin_ctz))
391# define V8_HAS_BUILTIN_EXPECT (__has_builtin(__builtin_expect))
392# define V8_HAS_BUILTIN_FRAME_ADDRESS (__has_builtin(__builtin_frame_address))
393# define V8_HAS_BUILTIN_MUL_OVERFLOW (__has_builtin(__builtin_mul_overflow))
394# define V8_HAS_BUILTIN_POPCOUNT (__has_builtin(__builtin_popcount))
395# define V8_HAS_BUILTIN_SADD_OVERFLOW (__has_builtin(__builtin_sadd_overflow))
396# define V8_HAS_BUILTIN_SMUL_OVERFLOW (__has_builtin(__builtin_smul_overflow))
397# define V8_HAS_BUILTIN_SSUB_OVERFLOW (__has_builtin(__builtin_ssub_overflow))
398# define V8_HAS_BUILTIN_SUB_OVERFLOW (__has_builtin(__builtin_sub_overflow))
399# define V8_HAS_BUILTIN_UADD_OVERFLOW (__has_builtin(__builtin_uadd_overflow))
400# define V8_HAS_BUILTIN_UNREACHABLE (__has_builtin(__builtin_unreachable))
401
402// Clang has no __has_feature for computed gotos.
403// GCC doc: https://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html
404# define V8_HAS_COMPUTED_GOTO 1
405
406#elif defined(__GNUC__)
407
408# define V8_CC_GNU 1
409# if defined(__INTEL_COMPILER) // Intel C++ also masquerades as GCC 3.2.0
410# define V8_CC_INTEL 1
411# endif
412# if defined(__MINGW32__)
413# define V8_CC_MINGW32 1
414# endif
415# if defined(__MINGW64__)
416# define V8_CC_MINGW64 1
417# endif
418# define V8_CC_MINGW (V8_CC_MINGW32 || V8_CC_MINGW64)
419
420// FYI: __has_builtin is only available with GCC 10 and later, so explicitly
421// check GCC version numbers to enable features. TODO(leszeks): Merge feature
422// enabling for GCC 10 and later into the Clang section above, and leave this
423// section for GCC 9 and earlier.
424
425// always_inline is available in gcc 4.0 but not very reliable until 4.4.
426// Works around "sorry, unimplemented: inlining failed" build errors with
427// older compilers.
428# define V8_HAS_ATTRIBUTE_ALWAYS_INLINE 1
429# define V8_HAS_ATTRIBUTE_NOINLINE 1
430# define V8_HAS_ATTRIBUTE_UNUSED 1
431# define V8_HAS_ATTRIBUTE_VISIBILITY 1
432# define V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT (!V8_CC_INTEL)
433# define V8_HAS_ATTRIBUTE_WEAK 1
434
435// [[nodiscard]] does not work together with with
436// __attribute__((visibility(""))) on GCC 7.4 which is why there is no define
437// for V8_HAS_CPP_ATTRIBUTE_NODISCARD. See https://crbug.com/v8/11707.
438
439# define V8_HAS_BUILTIN_ASSUME_ALIGNED 1
440# if __GNUC__ >= 11
441# define V8_HAS_BUILTIN_BIT_CAST 1
442# endif
443# define V8_HAS_BUILTIN_CLZ 1
444# define V8_HAS_BUILTIN_CTZ 1
445# define V8_HAS_BUILTIN_EXPECT 1
446# define V8_HAS_BUILTIN_FRAME_ADDRESS 1
447# define V8_HAS_BUILTIN_POPCOUNT 1
448# define V8_HAS_BUILTIN_UNREACHABLE 1
449
450// GCC doc: https://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html
451#define V8_HAS_COMPUTED_GOTO 1
452
453#endif
454
455#if defined(_MSC_VER)
456# define V8_CC_MSVC 1
457
458# define V8_HAS_DECLSPEC_NOINLINE 1
459# define V8_HAS_DECLSPEC_SELECTANY 1
460
461# define V8_HAS___FORCEINLINE 1
462
463#endif
464
465
466// -----------------------------------------------------------------------------
467// Helper macros
468
469// A macro used to make better inlining. Don't bother for debug builds.
470// Use like:
471// V8_INLINE int GetZero() { return 0; }
472#if !defined(DEBUG) && V8_HAS_ATTRIBUTE_ALWAYS_INLINE
473# define V8_INLINE inline __attribute__((always_inline))
474#elif !defined(DEBUG) && V8_HAS___FORCEINLINE
475# define V8_INLINE __forceinline
476#else
477# define V8_INLINE inline
478#endif
479
480#if V8_HAS_BUILTIN_ASSUME
481#ifdef DEBUG
482// In debug mode, check assumptions in addition to adding annotations.
483// This helps GCC (and maybe other compilers) figure out that certain
484// situations are unreachable.
485# define V8_ASSUME(condition) \
486 do { \
487 DCHECK(condition); \
488 __builtin_assume(condition); \
489 } while (false)
490#else // DEBUG
491# define V8_ASSUME __builtin_assume
492#endif // DEBUG
493#elif V8_HAS_BUILTIN_UNREACHABLE
494# define V8_ASSUME(condition) \
495 do { \
496 DCHECK(condition); \
497 if (!(condition)) __builtin_unreachable(); \
498 } while (false)
499#else
500# define V8_ASSUME USE
501#endif
502
503// Prefer c++20 std::assume_aligned
504#if __cplusplus >= 202002L && defined(__cpp_lib_assume_aligned)
505# define V8_ASSUME_ALIGNED(ptr, alignment) \
506 std::assume_aligned<(alignment)>(ptr)
507#elif V8_HAS_BUILTIN_ASSUME_ALIGNED
508# define V8_ASSUME_ALIGNED(ptr, alignment) \
509 __builtin_assume_aligned((ptr), (alignment))
510#else
511# define V8_ASSUME_ALIGNED(ptr, alignment) (ptr)
512#endif
513
514// A macro to mark functions whose values don't change (e.g. across calls)
515// and thereby compiler is free to hoist and fold multiple calls together.
516// Use like:
517// V8_CONST int foo() { ... }
518#if V8_HAS_ATTRIBUTE_CONST
519# define V8_CONST __attribute__((const))
520#else
521# define V8_CONST
522#endif
523
524// A macro to mark a declaration as requiring constant initialization.
525// Use like:
526// int* foo V8_CONSTINIT;
527#if V8_HAS_ATTRIBUTE_CONSTINIT
528# define V8_CONSTINIT __attribute__((require_constant_initialization))
529#else
530# define V8_CONSTINIT
531#endif
532
533
534// A macro to mark specific arguments as non-null.
535// Use like:
536// int add(int* x, int y, int* z) V8_NONNULL(1, 3) { return *x + y + *z; }
537#if V8_HAS_ATTRIBUTE_NONNULL
538# define V8_NONNULL(...) __attribute__((nonnull(__VA_ARGS__)))
539#else
540# define V8_NONNULL(...) /* NOT SUPPORTED */
541#endif
542
543
544// A macro used to tell the compiler to never inline a particular function.
545// Use like:
546// V8_NOINLINE int GetMinusOne() { return -1; }
547#if V8_HAS_ATTRIBUTE_NOINLINE
548# define V8_NOINLINE __attribute__((noinline))
549#elif V8_HAS_DECLSPEC_NOINLINE
550# define V8_NOINLINE __declspec(noinline)
551#else
552# define V8_NOINLINE /* NOT SUPPORTED */
553#endif
554
555
556// A macro used to change the calling conventions to preserve all registers (no
557// caller-saved registers). Use this for cold functions called from hot
558// functions.
559// Use like:
560// V8_NOINLINE V8_PRESERVE_MOST void UnlikelyMethod();
561#if V8_HAS_ATTRIBUTE_PRESERVE_MOST
562# define V8_PRESERVE_MOST __attribute__((preserve_most))
563#else
564# define V8_PRESERVE_MOST /* NOT SUPPORTED */
565#endif
566
567
568// A macro (V8_DEPRECATED) to mark classes or functions as deprecated.
569#if defined(V8_DEPRECATION_WARNINGS)
570# define V8_DEPRECATED(message) [[deprecated(message)]]
571#else
572# define V8_DEPRECATED(message)
573#endif
574
575
576// A macro (V8_DEPRECATE_SOON) to make it easier to see what will be deprecated.
577#if defined(V8_IMMINENT_DEPRECATION_WARNINGS)
578# define V8_DEPRECATE_SOON(message) [[deprecated(message)]]
579#else
580# define V8_DEPRECATE_SOON(message)
581#endif
582
583
584#if defined(V8_IMMINENT_DEPRECATION_WARNINGS) || \
585 defined(V8_DEPRECATION_WARNINGS)
586#if defined(V8_CC_MSVC)
587# define START_ALLOW_USE_DEPRECATED() \
588 __pragma(warning(push)) \
589 __pragma(warning(disable : 4996))
590# define END_ALLOW_USE_DEPRECATED() __pragma(warning(pop))
591#else // !defined(V8_CC_MSVC)
592# define START_ALLOW_USE_DEPRECATED() \
593 _Pragma("GCC diagnostic push") \
594 _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
595#define END_ALLOW_USE_DEPRECATED() _Pragma("GCC diagnostic pop")
596#endif // !defined(V8_CC_MSVC)
597#else // !(defined(V8_IMMINENT_DEPRECATION_WARNINGS) ||
598 // defined(V8_DEPRECATION_WARNINGS))
599#define START_ALLOW_USE_DEPRECATED()
600#define END_ALLOW_USE_DEPRECATED()
601#endif // !(defined(V8_IMMINENT_DEPRECATION_WARNINGS) ||
602 // defined(V8_DEPRECATION_WARNINGS))
603#define ALLOW_COPY_AND_MOVE_WITH_DEPRECATED_FIELDS(ClassName) \
604 START_ALLOW_USE_DEPRECATED() \
605 ClassName(const ClassName&) = default; \
606 ClassName(ClassName&&) = default; \
607 ClassName& operator=(const ClassName&) = default; \
608 ClassName& operator=(ClassName&&) = default; \
609 END_ALLOW_USE_DEPRECATED()
610
611
612#if defined(__GNUC__) && !defined(__clang__) && (__GNUC__ < 6)
613# define V8_ENUM_DEPRECATED(message)
614# define V8_ENUM_DEPRECATE_SOON(message)
615#else
616# define V8_ENUM_DEPRECATED(message) V8_DEPRECATED(message)
617# define V8_ENUM_DEPRECATE_SOON(message) V8_DEPRECATE_SOON(message)
618#endif
619
620
621// A macro to provide the compiler with branch prediction information.
622#if V8_HAS_BUILTIN_EXPECT
623# define V8_UNLIKELY(condition) (__builtin_expect(!!(condition), 0))
624# define V8_LIKELY(condition) (__builtin_expect(!!(condition), 1))
625#else
626# define V8_UNLIKELY(condition) (condition)
627# define V8_LIKELY(condition) (condition)
628#endif
629
630
631// Annotate a function indicating the caller must examine the return value.
632// Use like:
633// int foo() V8_WARN_UNUSED_RESULT;
634#if V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT
635#define V8_WARN_UNUSED_RESULT __attribute__((warn_unused_result))
636#else
637#define V8_WARN_UNUSED_RESULT /* NOT SUPPORTED */
638#endif
639
640
641// Annotate functions/variables as weak to allow overriding the symbol.
642#if V8_HAS_ATTRIBUTE_WEAK
643#define V8_WEAK __attribute__((weak))
644#else
645#define V8_WEAK /* NOT SUPPORTED */
646#endif
647
648
649// Annotate a class or constructor indicating the caller must assign the
650// constructed instances.
651// Apply to the whole class like:
652// class V8_NODISCARD Foo() { ... };
653// or apply to just one constructor like:
654// V8_NODISCARD Foo() { ... };
655// [[nodiscard]] comes in C++17 but supported in clang with -std >= c++11.
656#if V8_HAS_CPP_ATTRIBUTE_NODISCARD
657#define V8_NODISCARD [[nodiscard]]
658#else
659#define V8_NODISCARD /* NOT SUPPORTED */
660#endif
661
662// The no_unique_address attribute allows tail padding in a non-static data
663// member to overlap other members of the enclosing class (and in the special
664// case when the type is empty, permits it to fully overlap other members). The
665// field is laid out as if a base class were encountered at the corresponding
666// point within the class (except that it does not share a vptr with the
667// enclosing object).
668//
669// Apply to a data member like:
670//
671// class Foo {
672// V8_NO_UNIQUE_ADDRESS Bar bar_;
673// };
674//
675// [[no_unique_address]] comes in C++20 but supported in clang with
676// -std >= c++11.
677#if V8_HAS_CPP_ATTRIBUTE_NO_UNIQUE_ADDRESS
678#define V8_NO_UNIQUE_ADDRESS [[no_unique_address]]
679#else
680#define V8_NO_UNIQUE_ADDRESS /* NOT SUPPORTED */
681#endif
682
683// Marks a type as being eligible for the "trivial" ABI despite having a
684// non-trivial destructor or copy/move constructor. Such types can be relocated
685// after construction by simply copying their memory, which makes them eligible
686// to be passed in registers. The canonical example is std::unique_ptr.
687//
688// Use with caution; this has some subtle effects on constructor/destructor
689// ordering and will be very incorrect if the type relies on its address
690// remaining constant. When used as a function argument (by value), the value
691// may be constructed in the caller's stack frame, passed in a register, and
692// then used and destructed in the callee's stack frame. A similar thing can
693// occur when values are returned.
694//
695// TRIVIAL_ABI is not needed for types which have a trivial destructor and
696// copy/move constructors, since those are automatically trivial by the ABI
697// spec.
698//
699// It is also not likely to be effective on types too large to be passed in one
700// or two registers on typical target ABIs.
701//
702// See also:
703// https://clang.llvm.org/docs/AttributeReference.html#trivial-abi
704// https://libcxx.llvm.org/docs/DesignDocs/UniquePtrTrivialAbi.html
705#if defined(__clang__) && defined(__has_attribute)
706#if __has_attribute(trivial_abi)
707#define V8_TRIVIAL_ABI [[clang::trivial_abi]]
708#define V8_HAS_ATTRIBUTE_TRIVIAL_ABI 1
709#endif // __has_attribute(trivial_abi)
710#endif // defined(__clang__) && defined(__has_attribute)
711#if !defined(V8_TRIVIAL_ABI)
712#define V8_TRIVIAL_ABI
713#define V8_HAS_ATTRIBUTE_TRIVIAL_ABI 0
714#endif
715
716// Helper macro to define no_sanitize attributes only with clang.
717#if defined(__clang__) && defined(__has_attribute)
718#if __has_attribute(no_sanitize)
719#define V8_CLANG_NO_SANITIZE(what) __attribute__((no_sanitize(what)))
720#endif
721#endif
722#if !defined(V8_CLANG_NO_SANITIZE)
723#define V8_CLANG_NO_SANITIZE(what)
724#endif
725
726// Exposing private symbols requires exposing public symbols too.
727#ifdef BUILDING_V8_SHARED_PRIVATE
728#define BUILDING_V8_SHARED
729#endif
730
731#if defined(BUILDING_V8_SHARED) && defined(USING_V8_SHARED)
732#error Inconsistent build configuration: To build the V8 shared library \
733set BUILDING_V8_SHARED, to include its headers for linking against the \
734V8 shared library set USING_V8_SHARED.
735#endif
736
737#ifdef V8_OS_WIN
738
739// Setup for Windows DLL export/import. When building the V8 DLL the
740// BUILDING_V8_SHARED needs to be defined. When building a program which uses
741// the V8 DLL USING_V8_SHARED needs to be defined. When either building the V8
742// static library or building a program which uses the V8 static library neither
743// BUILDING_V8_SHARED nor USING_V8_SHARED should be defined.
744#ifdef BUILDING_V8_SHARED
745# define V8_EXPORT __declspec(dllexport)
746#elif USING_V8_SHARED
747# define V8_EXPORT __declspec(dllimport)
748#else
749# define V8_EXPORT
750#endif // BUILDING_V8_SHARED
751
752#else // V8_OS_WIN
753
754// Setup for Linux shared library export.
755#if V8_HAS_ATTRIBUTE_VISIBILITY
756# ifdef BUILDING_V8_SHARED
757# define V8_EXPORT __attribute__ ((visibility("default")))
758# else
759# define V8_EXPORT
760# endif
761#else
762# define V8_EXPORT
763#endif
764
765#endif // V8_OS_WIN
766
767// clang-format on
768
769// Processor architecture detection. For more info on what's defined, see:
770// http://msdn.microsoft.com/en-us/library/b0084kay.aspx
771// http://www.agner.org/optimize/calling_conventions.pdf
772// or with gcc, run: "echo | gcc -E -dM -"
773// The V8_HOST_ARCH_* macros correspond to the architecture on which V8, as a
774// virtual machine and compiler, runs. Don't confuse this with the architecture
775// on which V8 is built.
776#if defined(_M_X64) || defined(__x86_64__)
777#define V8_HOST_ARCH_X64 1
778#if defined(__x86_64__) && __SIZEOF_POINTER__ == 4 // Check for x32.
779#define V8_HOST_ARCH_32_BIT 1
780#else
781#define V8_HOST_ARCH_64_BIT 1
782#endif
783#elif defined(_M_IX86) || defined(__i386__)
784#define V8_HOST_ARCH_IA32 1
785#define V8_HOST_ARCH_32_BIT 1
786#elif defined(__AARCH64EL__) || defined(_M_ARM64)
787#define V8_HOST_ARCH_ARM64 1
788#define V8_HOST_ARCH_64_BIT 1
789#elif defined(__ARMEL__)
790#define V8_HOST_ARCH_ARM 1
791#define V8_HOST_ARCH_32_BIT 1
792#elif defined(__mips64)
793#define V8_HOST_ARCH_MIPS64 1
794#define V8_HOST_ARCH_64_BIT 1
795#elif defined(__loongarch_lp64)
796#define V8_HOST_ARCH_LOONG64 1
797#define V8_HOST_ARCH_64_BIT 1
798#elif defined(__PPC64__) || defined(_ARCH_PPC64)
799#define V8_HOST_ARCH_PPC64 1
800#define V8_HOST_ARCH_64_BIT 1
801#elif defined(__PPC__) || defined(_ARCH_PPC)
802#define V8_HOST_ARCH_PPC 1
803#define V8_HOST_ARCH_32_BIT 1
804#elif defined(__s390__) || defined(__s390x__)
805#define V8_HOST_ARCH_S390 1
806#if defined(__s390x__)
807#define V8_HOST_ARCH_64_BIT 1
808#else
809#define V8_HOST_ARCH_32_BIT 1
810#endif
811#elif defined(__riscv) || defined(__riscv__)
812#if __riscv_xlen == 64
813#define V8_HOST_ARCH_RISCV64 1
814#define V8_HOST_ARCH_64_BIT 1
815#elif __riscv_xlen == 32
816#define V8_HOST_ARCH_RISCV32 1
817#define V8_HOST_ARCH_32_BIT 1
818#else
819#error "Cannot detect Riscv's bitwidth"
820#endif
821#else
822#error "Host architecture was not detected as supported by v8"
823#endif
824
825// Target architecture detection. This corresponds to the architecture for which
826// V8's JIT will generate code (the last stage of the canadian cross-compiler).
827// The macros may be set externally. If not, detect in the same way as the host
828// architecture, that is, target the native environment as presented by the
829// compiler.
830#if !V8_TARGET_ARCH_X64 && !V8_TARGET_ARCH_IA32 && !V8_TARGET_ARCH_ARM && \
831 !V8_TARGET_ARCH_ARM64 && !V8_TARGET_ARCH_MIPS64 && !V8_TARGET_ARCH_PPC && \
832 !V8_TARGET_ARCH_PPC64 && !V8_TARGET_ARCH_S390 && \
833 !V8_TARGET_ARCH_RISCV64 && !V8_TARGET_ARCH_LOONG64 && \
834 !V8_TARGET_ARCH_RISCV32
835#if defined(_M_X64) || defined(__x86_64__)
836#define V8_TARGET_ARCH_X64 1
837#elif defined(_M_IX86) || defined(__i386__)
838#define V8_TARGET_ARCH_IA32 1
839#elif defined(__AARCH64EL__) || defined(_M_ARM64)
840#define V8_TARGET_ARCH_ARM64 1
841#elif defined(__ARMEL__)
842#define V8_TARGET_ARCH_ARM 1
843#elif defined(__mips64)
844#define V8_TARGET_ARCH_MIPS64 1
845#elif defined(__loongarch_lp64)
846#define V8_TARGET_ARCH_LOONG64 1
847#elif defined(_ARCH_PPC64)
848#define V8_TARGET_ARCH_PPC64 1
849#elif defined(_ARCH_PPC)
850#define V8_TARGET_ARCH_PPC 1
851#elif defined(__s390__)
852#define V8_TARGET_ARCH_S390 1
853#if defined(__s390x__)
854#define V8_TARGET_ARCH_S390X 1
855#endif
856#elif defined(__riscv) || defined(__riscv__)
857#if __riscv_xlen == 64
858#define V8_TARGET_ARCH_RISCV64 1
859#elif __riscv_xlen == 32
860#define V8_TARGET_ARCH_RISCV32 1
861#endif
862#else
863#error Target architecture was not detected as supported by v8
864#endif
865#endif
866
867// Determine architecture pointer size.
868#if V8_TARGET_ARCH_IA32
869#define V8_TARGET_ARCH_32_BIT 1
870#elif V8_TARGET_ARCH_X64
871#if !V8_TARGET_ARCH_32_BIT && !V8_TARGET_ARCH_64_BIT
872#if defined(__x86_64__) && __SIZEOF_POINTER__ == 4 // Check for x32.
873#define V8_TARGET_ARCH_32_BIT 1
874#else
875#define V8_TARGET_ARCH_64_BIT 1
876#endif
877#endif
878#elif V8_TARGET_ARCH_ARM
879#define V8_TARGET_ARCH_32_BIT 1
880#elif V8_TARGET_ARCH_ARM64
881#define V8_TARGET_ARCH_64_BIT 1
882#elif V8_TARGET_ARCH_MIPS
883#define V8_TARGET_ARCH_32_BIT 1
884#elif V8_TARGET_ARCH_MIPS64
885#define V8_TARGET_ARCH_64_BIT 1
886#elif V8_TARGET_ARCH_LOONG64
887#define V8_TARGET_ARCH_64_BIT 1
888#elif V8_TARGET_ARCH_PPC
889#define V8_TARGET_ARCH_32_BIT 1
890#elif V8_TARGET_ARCH_PPC64
891#define V8_TARGET_ARCH_64_BIT 1
892#elif V8_TARGET_ARCH_S390
893#if V8_TARGET_ARCH_S390X
894#define V8_TARGET_ARCH_64_BIT 1
895#else
896#define V8_TARGET_ARCH_32_BIT 1
897#endif
898#elif V8_TARGET_ARCH_RISCV64
899#define V8_TARGET_ARCH_64_BIT 1
900#elif V8_TARGET_ARCH_RISCV32
901#define V8_TARGET_ARCH_32_BIT 1
902#else
903#error Unknown target architecture pointer size
904#endif
905
906// Check for supported combinations of host and target architectures.
907#if V8_TARGET_ARCH_IA32 && !V8_HOST_ARCH_IA32
908#error Target architecture ia32 is only supported on ia32 host
909#endif
910#if (V8_TARGET_ARCH_X64 && V8_TARGET_ARCH_64_BIT && \
911 !((V8_HOST_ARCH_X64 || V8_HOST_ARCH_ARM64) && V8_HOST_ARCH_64_BIT))
912#error Target architecture x64 is only supported on x64 and arm64 host
913#endif
914#if (V8_TARGET_ARCH_X64 && V8_TARGET_ARCH_32_BIT && \
915 !(V8_HOST_ARCH_X64 && V8_HOST_ARCH_32_BIT))
916#error Target architecture x32 is only supported on x64 host with x32 support
917#endif
918#if (V8_TARGET_ARCH_ARM && !(V8_HOST_ARCH_IA32 || V8_HOST_ARCH_ARM))
919#error Target architecture arm is only supported on arm and ia32 host
920#endif
921#if (V8_TARGET_ARCH_ARM64 && !(V8_HOST_ARCH_X64 || V8_HOST_ARCH_ARM64))
922#error Target architecture arm64 is only supported on arm64 and x64 host
923#endif
924#if (V8_TARGET_ARCH_MIPS64 && !(V8_HOST_ARCH_X64 || V8_HOST_ARCH_MIPS64))
925#error Target architecture mips64 is only supported on mips64 and x64 host
926#endif
927#if (V8_TARGET_ARCH_RISCV64 && !(V8_HOST_ARCH_X64 || V8_HOST_ARCH_RISCV64))
928#error Target architecture riscv64 is only supported on riscv64 and x64 host
929#endif
930#if (V8_TARGET_ARCH_RISCV32 && !(V8_HOST_ARCH_IA32 || V8_HOST_ARCH_RISCV32))
931#error Target architecture riscv32 is only supported on riscv32 and ia32 host
932#endif
933#if (V8_TARGET_ARCH_LOONG64 && !(V8_HOST_ARCH_X64 || V8_HOST_ARCH_LOONG64))
934#error Target architecture loong64 is only supported on loong64 and x64 host
935#endif
936
937// Determine architecture endianness.
938#if V8_TARGET_ARCH_IA32
939#define V8_TARGET_LITTLE_ENDIAN 1
940#elif V8_TARGET_ARCH_X64
941#define V8_TARGET_LITTLE_ENDIAN 1
942#elif V8_TARGET_ARCH_ARM
943#define V8_TARGET_LITTLE_ENDIAN 1
944#elif V8_TARGET_ARCH_ARM64
945#define V8_TARGET_LITTLE_ENDIAN 1
946#elif V8_TARGET_ARCH_LOONG64
947#define V8_TARGET_LITTLE_ENDIAN 1
948#elif V8_TARGET_ARCH_MIPS64
949#if defined(__MIPSEB__) || defined(V8_TARGET_ARCH_MIPS64_BE)
950#define V8_TARGET_BIG_ENDIAN 1
951#else
952#define V8_TARGET_LITTLE_ENDIAN 1
953#endif
954#elif defined(__BIG_ENDIAN__) // FOR PPCGR on AIX
955#define V8_TARGET_BIG_ENDIAN 1
956#elif V8_TARGET_ARCH_PPC_LE
957#define V8_TARGET_LITTLE_ENDIAN 1
958#elif V8_TARGET_ARCH_PPC_BE
959#define V8_TARGET_BIG_ENDIAN 1
960#elif V8_TARGET_ARCH_S390
961#if V8_TARGET_ARCH_S390_LE_SIM
962#define V8_TARGET_LITTLE_ENDIAN 1
963#else
964#define V8_TARGET_BIG_ENDIAN 1
965#endif
966#elif V8_TARGET_ARCH_RISCV32 || V8_TARGET_ARCH_RISCV64
967#define V8_TARGET_LITTLE_ENDIAN 1
968#elif defined(__BYTE_ORDER__)
969#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
970#define V8_TARGET_BIG_ENDIAN 1
971#else
972#define V8_TARGET_LITTLE_ENDIAN 1
973#endif
974#else
975#error Unknown target architecture endianness
976#endif
977
978#undef V8_HAS_CPP_ATTRIBUTE
979
980#if !defined(V8_STATIC_ROOTS)
981#define V8_STATIC_ROOTS_BOOL false
982#else
983#define V8_STATIC_ROOTS_BOOL true
984#endif
985
986#endif // V8CONFIG_H_