ClickHouse/base/base/defines.h
2023-02-09 14:49:22 -05:00

196 lines
9.1 KiB
C++

#pragma once
/// __has_feature supported only by clang.
///
/// But libcxx/libcxxabi overrides it to 0,
/// thus the checks for __has_feature will be wrong.
///
/// NOTE:
/// - __has_feature cannot be simply undefined,
/// since this will be broken if some C++ header will be included after
/// including <base/defines.h>
/// - it should not have fallback to 0,
/// since this may create false-positive detection (common problem)
#if defined(__clang__) && defined(__has_feature)
# define ch_has_feature __has_feature
#endif
#if !defined(likely)
# define likely(x) (__builtin_expect(!!(x), 1))
#endif
#if !defined(unlikely)
# define unlikely(x) (__builtin_expect(!!(x), 0))
#endif
// more aliases: https://mailman.videolan.org/pipermail/x264-devel/2014-May/010660.html
#define ALWAYS_INLINE __attribute__((__always_inline__))
#define NO_INLINE __attribute__((__noinline__))
#define MAY_ALIAS __attribute__((__may_alias__))
#if !defined(__x86_64__) && !defined(__aarch64__) && !defined(__PPC__) && !defined(__s390x__) && !(defined(__riscv) && (__riscv_xlen == 64))
# error "The only supported platforms are x86_64 and AArch64, PowerPC (work in progress), s390x (work in progress) and RISC-V 64 (experimental)"
#endif
/// Check for presence of address sanitizer
#if !defined(ADDRESS_SANITIZER)
# if defined(ch_has_feature)
# if ch_has_feature(address_sanitizer)
# define ADDRESS_SANITIZER 1
# endif
# elif defined(__SANITIZE_ADDRESS__)
# define ADDRESS_SANITIZER 1
# endif
#endif
#if !defined(THREAD_SANITIZER)
# if defined(ch_has_feature)
# if ch_has_feature(thread_sanitizer)
# define THREAD_SANITIZER 1
# endif
# elif defined(__SANITIZE_THREAD__)
# define THREAD_SANITIZER 1
# endif
#endif
#if !defined(MEMORY_SANITIZER)
# if defined(ch_has_feature)
# if ch_has_feature(memory_sanitizer)
# define MEMORY_SANITIZER 1
# endif
# elif defined(__MEMORY_SANITIZER__)
# define MEMORY_SANITIZER 1
# endif
#endif
#if !defined(UNDEFINED_BEHAVIOR_SANITIZER)
# if defined(__has_feature)
# if __has_feature(undefined_behavior_sanitizer)
# define UNDEFINED_BEHAVIOR_SANITIZER 1
# endif
# elif defined(__UNDEFINED_BEHAVIOR_SANITIZER__)
# define UNDEFINED_BEHAVIOR_SANITIZER 1
# endif
#endif
#if defined(ADDRESS_SANITIZER)
# define BOOST_USE_ASAN 1
# define BOOST_USE_UCONTEXT 1
#endif
#if defined(THREAD_SANITIZER)
# define BOOST_USE_TSAN 1
# define BOOST_USE_UCONTEXT 1
#endif
/// TODO: Strange enough, there is no way to detect UB sanitizer.
/// Explicitly allow undefined behaviour for certain functions. Use it as a function attribute.
/// It is useful in case when compiler cannot see (and exploit) it, but UBSan can.
/// Example: multiplication of signed integers with possibility of overflow when both sides are from user input.
#if defined(__clang__)
# define NO_SANITIZE_UNDEFINED __attribute__((__no_sanitize__("undefined")))
# define NO_SANITIZE_ADDRESS __attribute__((__no_sanitize__("address")))
# define NO_SANITIZE_THREAD __attribute__((__no_sanitize__("thread")))
# define ALWAYS_INLINE_NO_SANITIZE_UNDEFINED __attribute__((__always_inline__, __no_sanitize__("undefined")))
#else /// It does not work in GCC. GCC 7 cannot recognize this attribute and GCC 8 simply ignores it.
# define NO_SANITIZE_UNDEFINED
# define NO_SANITIZE_ADDRESS
# define NO_SANITIZE_THREAD
# define ALWAYS_INLINE_NO_SANITIZE_UNDEFINED ALWAYS_INLINE
#endif
#if defined(__clang__) && defined(__clang_major__) && __clang_major__ >= 14
# define DISABLE_SANITIZER_INSTRUMENTATION __attribute__((disable_sanitizer_instrumentation))
#else
# define DISABLE_SANITIZER_INSTRUMENTATION
#endif
#if !__has_include(<sanitizer/asan_interface.h>) || !defined(ADDRESS_SANITIZER)
# define ASAN_UNPOISON_MEMORY_REGION(a, b)
# define ASAN_POISON_MEMORY_REGION(a, b)
#endif
#if !defined(ABORT_ON_LOGICAL_ERROR)
#if !defined(NDEBUG) || defined(ADDRESS_SANITIZER) || defined(THREAD_SANITIZER) || defined(MEMORY_SANITIZER) || defined(UNDEFINED_BEHAVIOR_SANITIZER)
#define ABORT_ON_LOGICAL_ERROR
#endif
#endif
/// chassert(x) is similar to assert(x), but:
/// - works in builds with sanitizers, not only in debug builds
/// - tries to print failed assertion into server log
/// It can be used for all assertions except heavy ones.
/// Heavy assertions (that run loops or call complex functions) are allowed in debug builds only.
/// Also it makes sense to call abort() instead of __builtin_unreachable() in debug builds,
/// because SIGABRT is easier to debug than SIGTRAP (the second one makes gdb crazy)
#if !defined(chassert)
#if defined(ABORT_ON_LOGICAL_ERROR)
#define chassert(x) static_cast<bool>(x) ? void(0) : ::DB::abortOnFailedAssertion(#x)
#define UNREACHABLE() abort()
#else
/// Here sizeof() trick is used to suppress unused warning for result,
/// since simple "(void)x" will evaluate the expression, while
/// "sizeof(!(x))" will not.
#define NIL_EXPRESSION(x) (void)sizeof(!(x))
#define chassert(x) NIL_EXPRESSION(x)
#define UNREACHABLE() __builtin_unreachable()
#endif
#endif
/// Macros for Clang Thread Safety Analysis (TSA). They can be safely ignored by other compilers.
/// Feel free to extend, but please stay close to https://clang.llvm.org/docs/ThreadSafetyAnalysis.html#mutexheader
#if defined(__clang__)
# define TSA_GUARDED_BY(...) __attribute__((guarded_by(__VA_ARGS__))) /// data is protected by given capability
# define TSA_PT_GUARDED_BY(...) __attribute__((pt_guarded_by(__VA_ARGS__))) /// pointed-to data is protected by the given capability
# define TSA_REQUIRES(...) __attribute__((requires_capability(__VA_ARGS__))) /// thread needs exclusive possession of given capability
# define TSA_REQUIRES_SHARED(...) __attribute__((requires_shared_capability(__VA_ARGS__))) /// thread needs shared possession of given capability
# define TSA_ACQUIRED_AFTER(...) __attribute__((acquired_after(__VA_ARGS__))) /// annotated lock must be locked after given lock
# define TSA_NO_THREAD_SAFETY_ANALYSIS __attribute__((no_thread_safety_analysis)) /// disable TSA for a function
# define TSA_CAPABILITY(...) __attribute__((capability(__VA_ARGS__))) /// object of a class can be used as capability
# define TSA_ACQUIRE(...) __attribute__((acquire_capability(__VA_ARGS__))) /// function acquires a capability, but does not release it
# define TSA_TRY_ACQUIRE(...) __attribute__((try_acquire_capability(__VA_ARGS__))) /// function tries to acquire a capability and returns a boolean value indicating success or failure
# define TSA_RELEASE(...) __attribute__((release_capability(__VA_ARGS__))) /// function releases the given capability
# define TSA_ACQUIRE_SHARED(...) __attribute__((acquire_shared_capability(__VA_ARGS__))) /// function acquires a shared capability, but does not release it
# define TSA_TRY_ACQUIRE_SHARED(...) __attribute__((try_acquire_shared_capability(__VA_ARGS__))) /// function tries to acquire a shared capability and returns a boolean value indicating success or failure
# define TSA_RELEASE_SHARED(...) __attribute__((release_shared_capability(__VA_ARGS__))) /// function releases the given shared capability
/// Macros for suppressing TSA warnings for specific reads/writes (instead of suppressing it for the whole function)
/// They use a lambda function to apply function attribute to a single statement. This enable us to suppress warnings locally instead of
/// suppressing them in the whole function
/// Consider adding a comment when using these macros.
# define TSA_SUPPRESS_WARNING_FOR_READ(x) ([&]() TSA_NO_THREAD_SAFETY_ANALYSIS -> const auto & { return (x); }())
# define TSA_SUPPRESS_WARNING_FOR_WRITE(x) ([&]() TSA_NO_THREAD_SAFETY_ANALYSIS -> auto & { return (x); }())
/// This macro is useful when only one thread writes to a member
/// and you want to read this member from the same thread without locking a mutex.
/// It's safe (because no concurrent writes are possible), but TSA generates a warning.
/// (Seems like there's no way to verify it, but it makes sense to distinguish it from TSA_SUPPRESS_WARNING_FOR_READ for readability)
# define TSA_READ_ONE_THREAD(x) TSA_SUPPRESS_WARNING_FOR_READ(x)
#else
# define TSA_GUARDED_BY(...)
# define TSA_PT_GUARDED_BY(...)
# define TSA_REQUIRES(...)
# define TSA_REQUIRES_SHARED(...)
# define TSA_NO_THREAD_SAFETY_ANALYSIS
# define TSA_CAPABILITY(...)
# define TSA_ACQUIRE(...)
# define TSA_TRY_ACQUIRE(...)
# define TSA_RELEASE(...)
# define TSA_ACQUIRE_SHARED(...)
# define TSA_TRY_ACQUIRE_SHARED(...)
# define TSA_RELEASE_SHARED(...)
# define TSA_SUPPRESS_WARNING_FOR_READ(x) (x)
# define TSA_SUPPRESS_WARNING_FOR_WRITE(x) (x)
# define TSA_READ_ONE_THREAD(x) TSA_SUPPRESS_WARNING_FOR_READ(x)
#endif
/// A template function for suppressing warnings about unused variables or function results.
template <typename... Args>
constexpr void UNUSED(Args &&... args [[maybe_unused]])
{
}