forked from OSchip/llvm-project
106 lines
3.4 KiB
C++
106 lines
3.4 KiB
C++
//===-- sanitizer_atomic_clang.h --------------------------------*- C++ -*-===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file is a part of ThreadSanitizer/AddressSanitizer runtime.
|
|
// Not intended for direct inclusion. Include sanitizer_atomic.h.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef SANITIZER_ATOMIC_CLANG_H
|
|
#define SANITIZER_ATOMIC_CLANG_H
|
|
|
|
#if defined(__i386__) || defined(__x86_64__)
|
|
# include "sanitizer_atomic_clang_x86.h"
|
|
#else
|
|
# include "sanitizer_atomic_clang_other.h"
|
|
#endif
|
|
|
|
namespace __sanitizer {
|
|
|
|
// We would like to just use compiler builtin atomic operations
|
|
// for loads and stores, but they are mostly broken in clang:
|
|
// - they lead to vastly inefficient code generation
|
|
// (http://llvm.org/bugs/show_bug.cgi?id=17281)
|
|
// - 64-bit atomic operations are not implemented on x86_32
|
|
// (http://llvm.org/bugs/show_bug.cgi?id=15034)
|
|
// - they are not implemented on ARM
|
|
// error: undefined reference to '__atomic_load_4'
|
|
|
|
// See http://www.cl.cam.ac.uk/~pes20/cpp/cpp0xmappings.html
|
|
// for mappings of the memory model to different processors.
|
|
|
|
INLINE void atomic_signal_fence(memory_order) {
|
|
__asm__ __volatile__("" ::: "memory");
|
|
}
|
|
|
|
INLINE void atomic_thread_fence(memory_order) {
|
|
__sync_synchronize();
|
|
}
|
|
|
|
template<typename T>
|
|
INLINE typename T::Type atomic_fetch_add(volatile T *a,
|
|
typename T::Type v, memory_order mo) {
|
|
(void)mo;
|
|
DCHECK(!((uptr)a % sizeof(*a)));
|
|
return __sync_fetch_and_add(&a->val_dont_use, v);
|
|
}
|
|
|
|
template<typename T>
|
|
INLINE typename T::Type atomic_fetch_sub(volatile T *a,
|
|
typename T::Type v, memory_order mo) {
|
|
(void)mo;
|
|
DCHECK(!((uptr)a % sizeof(*a)));
|
|
return __sync_fetch_and_add(&a->val_dont_use, -v);
|
|
}
|
|
|
|
template<typename T>
|
|
INLINE typename T::Type atomic_exchange(volatile T *a,
|
|
typename T::Type v, memory_order mo) {
|
|
DCHECK(!((uptr)a % sizeof(*a)));
|
|
if (mo & (memory_order_release | memory_order_acq_rel | memory_order_seq_cst))
|
|
__sync_synchronize();
|
|
v = __sync_lock_test_and_set(&a->val_dont_use, v);
|
|
if (mo == memory_order_seq_cst)
|
|
__sync_synchronize();
|
|
return v;
|
|
}
|
|
|
|
template <typename T>
|
|
INLINE bool atomic_compare_exchange_strong(volatile T *a, typename T::Type *cmp,
|
|
typename T::Type xchg,
|
|
memory_order mo) {
|
|
typedef typename T::Type Type;
|
|
Type cmpv = *cmp;
|
|
Type prev;
|
|
prev = __sync_val_compare_and_swap(&a->val_dont_use, cmpv, xchg);
|
|
if (prev == cmpv) return true;
|
|
*cmp = prev;
|
|
return false;
|
|
}
|
|
|
|
template<typename T>
|
|
INLINE bool atomic_compare_exchange_weak(volatile T *a,
|
|
typename T::Type *cmp,
|
|
typename T::Type xchg,
|
|
memory_order mo) {
|
|
return atomic_compare_exchange_strong(a, cmp, xchg, mo);
|
|
}
|
|
|
|
} // namespace __sanitizer
|
|
|
|
// This include provides explicit template instantiations for atomic_uint64_t
|
|
// on MIPS32, which does not directly support 8 byte atomics. It has to
|
|
// proceed the template definitions above.
|
|
#if defined(_MIPS_SIM) && defined(_ABIO32)
|
|
#include "sanitizer_atomic_clang_mips.h"
|
|
#endif
|
|
|
|
#undef ATOMIC_ORDER
|
|
|
|
#endif // SANITIZER_ATOMIC_CLANG_H
|