ladybird/AK/Platform.h
Daniel Bertalan 515e2d9734 AK: Use conditionally trivial special member functions
This commit makes use of the conditionally trivial special member
functions introduced in C++20. Basically, `Optional` and `Variant`
inherits whether its wrapped type is trivially copy constructible,
trivially copy assignable or trivially destructible. This lets the
compiler optimize optimize a large number of their use cases.

The constraints have been applied to `Optional`'s converting
constructors too in order to make the API more explicit.

This feature is not supported by Clang yet, so we use conditional
compilation so that Lagom can be built on macOS. Once Clang has P0848R3
support, these can be removed.
2021-07-04 07:24:41 +04:30

101 lines
2.3 KiB
C

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#ifdef __i386__
# define AK_ARCH_I386 1
#endif
#ifdef __x86_64__
# define AK_ARCH_X86_64 1
#endif
#if defined(__APPLE__) && defined(__MACH__)
# define AK_OS_MACOS
# define AK_OS_BSD_GENERIC
#endif
#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
# define AK_OS_BSD_GENERIC
#endif
#define ARCH(arch) (defined(AK_ARCH_##arch) && AK_ARCH_##arch)
#if !defined(__clang__)
# define AK_HAS_CONDITIONALLY_TRIVIAL
#endif
#ifdef ALWAYS_INLINE
# undef ALWAYS_INLINE
#endif
#define ALWAYS_INLINE __attribute__((always_inline)) inline
#ifdef NEVER_INLINE
# undef NEVER_INLINE
#endif
#define NEVER_INLINE __attribute__((noinline))
#ifdef FLATTEN
# undef FLATTEN
#endif
#define FLATTEN __attribute__((flatten))
#ifdef RETURNS_NONNULL
# undef RETURNS_NONNULL
#endif
#define RETURNS_NONNULL __attribute__((returns_nonnull))
#ifdef NO_SANITIZE_ADDRESS
# undef NO_SANITIZE_ADDRESS
#endif
#define NO_SANITIZE_ADDRESS __attribute__((no_sanitize_address))
// GCC doesn't have __has_feature but clang does
#ifndef __has_feature
# define __has_feature(...) 0
#endif
#if __has_feature(address_sanitizer) || defined(__SANITIZE_ADDRESS__)
# define HAS_ADDRESS_SANITIZER
# define ASAN_POISON_MEMORY_REGION(addr, size) __asan_poison_memory_region(addr, size)
# define ASAN_UNPOISON_MEMORY_REGION(addr, size) __asan_unpoison_memory_region(addr, size)
#else
# define ASAN_POISON_MEMORY_REGION(addr, size)
# define ASAN_UNPOISON_MEMORY_REGION(addr, size)
#endif
#ifndef __serenity__
# include <unistd.h>
# undef PAGE_SIZE
# define PAGE_SIZE sysconf(_SC_PAGESIZE)
#endif
ALWAYS_INLINE int count_trailing_zeroes_32(unsigned int val)
{
#if defined(__GNUC__) || defined(__clang__)
return __builtin_ctz(val);
#else
for (u8 i = 0; i < 32; ++i) {
if ((val >> i) & 1) {
return i;
}
}
return 0;
#endif
}
ALWAYS_INLINE int count_trailing_zeroes_32_safe(unsigned int val)
{
if (val == 0)
return 32;
return count_trailing_zeroes_32(val);
}
#ifdef AK_OS_BSD_GENERIC
# define CLOCK_MONOTONIC_COARSE CLOCK_MONOTONIC
# define CLOCK_REALTIME_COARSE CLOCK_REALTIME
#endif