lib/tsan/rtl/tsan_interceptors_mac.cc - platform/external/compiler-rt - Git at Google

 //===-- tsan_interceptors_mac.cc ------------------------------------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file is a part of ThreadSanitizer (TSan), a race detector.
 //
 // Mac-specific interceptors.
 //===----------------------------------------------------------------------===//

 #include "sanitizer_common/sanitizer_platform.h"
 #if SANITIZER_MAC

 #include "interception/interception.h"
 #include "tsan_interceptors.h"
 #include "tsan_interface.h"
 #include "tsan_interface_ann.h"

 #include <libkern/OSAtomic.h>
 #include <xpc/xpc.h>

 typedef long long_t;  // NOLINT

 namespace __tsan {

 // The non-barrier versions of OSAtomic* functions are semantically mo_relaxed,
 // but the two variants (e.g. OSAtomicAdd32 and OSAtomicAdd32Barrier) are
 // actually aliases of each other, and we cannot have different interceptors for
 // them, because they're actually the same function.  Thus, we have to stay
 // conservative and treat the non-barrier versions as mo_acq_rel.
 static const morder kMacOrderBarrier = mo_acq_rel;
 static const morder kMacOrderNonBarrier = mo_acq_rel;

 #define OSATOMIC_INTERCEPTOR(return_t, t, tsan_t, f, tsan_atomic_f, mo) \
   TSAN_INTERCEPTOR(return_t, f, t x, volatile t *ptr) {                 \
     SCOPED_TSAN_INTERCEPTOR(f, x, ptr);                                 \
     return tsan_atomic_f((volatile tsan_t *)ptr, x, mo);                \
   }

 #define OSATOMIC_INTERCEPTOR_PLUS_X(return_t, t, tsan_t, f, tsan_atomic_f, mo) \
   TSAN_INTERCEPTOR(return_t, f, t x, volatile t *ptr) {                        \
     SCOPED_TSAN_INTERCEPTOR(f, x, ptr);                                        \
     return tsan_atomic_f((volatile tsan_t *)ptr, x, mo) + x;                   \
   }

 #define OSATOMIC_INTERCEPTOR_PLUS_1(return_t, t, tsan_t, f, tsan_atomic_f, mo) \
   TSAN_INTERCEPTOR(return_t, f, volatile t *ptr) {                             \
     SCOPED_TSAN_INTERCEPTOR(f, ptr);                                           \
     return tsan_atomic_f((volatile tsan_t *)ptr, 1, mo) + 1;                   \
   }

 #define OSATOMIC_INTERCEPTOR_MINUS_1(return_t, t, tsan_t, f, tsan_atomic_f, \
                                      mo)                                    \
   TSAN_INTERCEPTOR(return_t, f, volatile t *ptr) {                          \
     SCOPED_TSAN_INTERCEPTOR(f, ptr);                                        \
     return tsan_atomic_f((volatile tsan_t *)ptr, 1, mo) - 1;                \
   }

 #define OSATOMIC_INTERCEPTORS_ARITHMETIC(f, tsan_atomic_f, m)                  \
   m(int32_t, int32_t, a32, f##32, __tsan_atomic32_##tsan_atomic_f,             \
     kMacOrderNonBarrier)                                                       \
   m(int32_t, int32_t, a32, f##32##Barrier, __tsan_atomic32_##tsan_atomic_f,    \
     kMacOrderBarrier)                                                          \
   m(int64_t, int64_t, a64, f##64, __tsan_atomic64_##tsan_atomic_f,             \
     kMacOrderNonBarrier)                                                       \
   m(int64_t, int64_t, a64, f##64##Barrier, __tsan_atomic64_##tsan_atomic_f,    \
     kMacOrderBarrier)

 #define OSATOMIC_INTERCEPTORS_BITWISE(f, tsan_atomic_f, m, m_orig)             \
   m(int32_t, uint32_t, a32, f##32, __tsan_atomic32_##tsan_atomic_f,            \
     kMacOrderNonBarrier)                                                       \
   m(int32_t, uint32_t, a32, f##32##Barrier, __tsan_atomic32_##tsan_atomic_f,   \
     kMacOrderBarrier)                                                          \
   m_orig(int32_t, uint32_t, a32, f##32##Orig, __tsan_atomic32_##tsan_atomic_f, \
     kMacOrderNonBarrier)                                                       \
   m_orig(int32_t, uint32_t, a32, f##32##OrigBarrier,                           \
     __tsan_atomic32_##tsan_atomic_f, kMacOrderBarrier)

 OSATOMIC_INTERCEPTORS_ARITHMETIC(OSAtomicAdd, fetch_add,
                                  OSATOMIC_INTERCEPTOR_PLUS_X)
 OSATOMIC_INTERCEPTORS_ARITHMETIC(OSAtomicIncrement, fetch_add,
                                  OSATOMIC_INTERCEPTOR_PLUS_1)
 OSATOMIC_INTERCEPTORS_ARITHMETIC(OSAtomicDecrement, fetch_sub,
                                  OSATOMIC_INTERCEPTOR_MINUS_1)
 OSATOMIC_INTERCEPTORS_BITWISE(OSAtomicOr, fetch_or, OSATOMIC_INTERCEPTOR_PLUS_X,
                               OSATOMIC_INTERCEPTOR)
 OSATOMIC_INTERCEPTORS_BITWISE(OSAtomicAnd, fetch_and,
                               OSATOMIC_INTERCEPTOR_PLUS_X, OSATOMIC_INTERCEPTOR)
 OSATOMIC_INTERCEPTORS_BITWISE(OSAtomicXor, fetch_xor,
                               OSATOMIC_INTERCEPTOR_PLUS_X, OSATOMIC_INTERCEPTOR)

 #define OSATOMIC_INTERCEPTORS_CAS(f, tsan_atomic_f, tsan_t, t)              \
   TSAN_INTERCEPTOR(bool, f, t old_value, t new_value, t volatile *ptr) {    \
     SCOPED_TSAN_INTERCEPTOR(f, old_value, new_value, ptr);                  \
     return tsan_atomic_f##_compare_exchange_strong(                         \
         (tsan_t *)ptr, (tsan_t *)&old_value, (tsan_t)new_value,             \
         kMacOrderNonBarrier, kMacOrderNonBarrier);                          \
   }                                                                         \
                                                                             \
   TSAN_INTERCEPTOR(bool, f##Barrier, t old_value, t new_value,              \
                    t volatile *ptr) {                                       \
     SCOPED_TSAN_INTERCEPTOR(f##Barrier, old_value, new_value, ptr);         \
     return tsan_atomic_f##_compare_exchange_strong(                         \
         (tsan_t *)ptr, (tsan_t *)&old_value, (tsan_t)new_value,             \
         kMacOrderBarrier, kMacOrderNonBarrier);                             \
   }

 OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwapInt, __tsan_atomic32, a32, int)
 OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwapLong, __tsan_atomic64, a64,
                           long_t)
 OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwapPtr, __tsan_atomic64, a64,
                           void *)
 OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwap32, __tsan_atomic32, a32,
                           int32_t)
 OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwap64, __tsan_atomic64, a64,
                           int64_t)

 #define OSATOMIC_INTERCEPTOR_BITOP(f, op, m, mo)              \
   TSAN_INTERCEPTOR(bool, f, uint32_t n, volatile void *ptr) { \
     SCOPED_TSAN_INTERCEPTOR(f, n, ptr);                       \
     char *byte_ptr = ((char *)ptr) + (n >> 3);                \
     char bit_index = n & 7;                                   \
     char mask = m;                                            \
     char orig_byte = op((a8 *)byte_ptr, mask, mo);            \
     return orig_byte & mask;                                  \
   }

 #define OSATOMIC_INTERCEPTORS_BITOP(f, op, m)                     \
   OSATOMIC_INTERCEPTOR_BITOP(f, op, m, kMacOrderNonBarrier)       \
   OSATOMIC_INTERCEPTOR_BITOP(f##Barrier, op, m, kMacOrderBarrier)

 OSATOMIC_INTERCEPTORS_BITOP(OSAtomicTestAndSet, __tsan_atomic8_fetch_or,
                             0x80u >> bit_index)
 OSATOMIC_INTERCEPTORS_BITOP(OSAtomicTestAndClear, __tsan_atomic8_fetch_and,
                             ~(0x80u >> bit_index))

 TSAN_INTERCEPTOR(void, OSAtomicEnqueue, OSQueueHead *list, void *item,
                  size_t offset) {
   SCOPED_TSAN_INTERCEPTOR(OSAtomicEnqueue, list, item, offset);
   __tsan_release(item);
   REAL(OSAtomicEnqueue)(list, item, offset);
 }

 TSAN_INTERCEPTOR(void *, OSAtomicDequeue, OSQueueHead *list, size_t offset) {
   SCOPED_TSAN_INTERCEPTOR(OSAtomicDequeue, list, offset);
   void *item = REAL(OSAtomicDequeue)(list, offset);
   if (item) __tsan_acquire(item);
   return item;
 }

 // OSAtomicFifoEnqueue and OSAtomicFifoDequeue are only on OS X.
 #if !SANITIZER_IOS

 TSAN_INTERCEPTOR(void, OSAtomicFifoEnqueue, OSFifoQueueHead *list, void *item,
                  size_t offset) {
   SCOPED_TSAN_INTERCEPTOR(OSAtomicFifoEnqueue, list, item, offset);
   __tsan_release(item);
   REAL(OSAtomicFifoEnqueue)(list, item, offset);
 }

 TSAN_INTERCEPTOR(void *, OSAtomicFifoDequeue, OSFifoQueueHead *list,
                  size_t offset) {
   SCOPED_TSAN_INTERCEPTOR(OSAtomicFifoDequeue, list, offset);
   void *item = REAL(OSAtomicFifoDequeue)(list, offset);
   if (item) __tsan_acquire(item);
   return item;
 }

 #endif

 TSAN_INTERCEPTOR(void, OSSpinLockLock, volatile OSSpinLock *lock) {
   CHECK(!cur_thread()->is_dead);
   if (!cur_thread()->is_inited) {
     return REAL(OSSpinLockLock)(lock);
   }
   SCOPED_TSAN_INTERCEPTOR(OSSpinLockLock, lock);
   REAL(OSSpinLockLock)(lock);
   Acquire(thr, pc, (uptr)lock);
 }

 TSAN_INTERCEPTOR(bool, OSSpinLockTry, volatile OSSpinLock *lock) {
   CHECK(!cur_thread()->is_dead);
   if (!cur_thread()->is_inited) {
     return REAL(OSSpinLockTry)(lock);
   }
   SCOPED_TSAN_INTERCEPTOR(OSSpinLockTry, lock);
   bool result = REAL(OSSpinLockTry)(lock);
   if (result)
     Acquire(thr, pc, (uptr)lock);
   return result;
 }

 TSAN_INTERCEPTOR(void, OSSpinLockUnlock, volatile OSSpinLock *lock) {
   CHECK(!cur_thread()->is_dead);
   if (!cur_thread()->is_inited) {
     return REAL(OSSpinLockUnlock)(lock);
   }
   SCOPED_TSAN_INTERCEPTOR(OSSpinLockUnlock, lock);
   Release(thr, pc, (uptr)lock);
   REAL(OSSpinLockUnlock)(lock);
 }

 TSAN_INTERCEPTOR(void, os_lock_lock, void *lock) {
   CHECK(!cur_thread()->is_dead);
   if (!cur_thread()->is_inited) {
     return REAL(os_lock_lock)(lock);
   }
   SCOPED_TSAN_INTERCEPTOR(os_lock_lock, lock);
   REAL(os_lock_lock)(lock);
   Acquire(thr, pc, (uptr)lock);
 }

 TSAN_INTERCEPTOR(bool, os_lock_trylock, void *lock) {
   CHECK(!cur_thread()->is_dead);
   if (!cur_thread()->is_inited) {
     return REAL(os_lock_trylock)(lock);
   }
   SCOPED_TSAN_INTERCEPTOR(os_lock_trylock, lock);
   bool result = REAL(os_lock_trylock)(lock);
   if (result)
     Acquire(thr, pc, (uptr)lock);
   return result;
 }

 TSAN_INTERCEPTOR(void, os_lock_unlock, void *lock) {
   CHECK(!cur_thread()->is_dead);
   if (!cur_thread()->is_inited) {
     return REAL(os_lock_unlock)(lock);
   }
   SCOPED_TSAN_INTERCEPTOR(os_lock_unlock, lock);
   Release(thr, pc, (uptr)lock);
   REAL(os_lock_unlock)(lock);
 }

 TSAN_INTERCEPTOR(void, xpc_connection_set_event_handler,
                  xpc_connection_t connection, xpc_handler_t handler) {
   SCOPED_TSAN_INTERCEPTOR(xpc_connection_set_event_handler, connection,
                           handler);
   Release(thr, pc, (uptr)connection);
   xpc_handler_t new_handler = ^(xpc_object_t object) {
     {
       SCOPED_INTERCEPTOR_RAW(xpc_connection_set_event_handler);
       Acquire(thr, pc, (uptr)connection);
     }
     handler(object);
   };
   REAL(xpc_connection_set_event_handler)(connection, new_handler);
 }

 TSAN_INTERCEPTOR(void, xpc_connection_send_barrier, xpc_connection_t connection,
                  dispatch_block_t barrier) {
   SCOPED_TSAN_INTERCEPTOR(xpc_connection_send_barrier, connection, barrier);
   Release(thr, pc, (uptr)connection);
   dispatch_block_t new_barrier = ^() {
     {
       SCOPED_INTERCEPTOR_RAW(xpc_connection_send_barrier);
       Acquire(thr, pc, (uptr)connection);
     }
     barrier();
   };
   REAL(xpc_connection_send_barrier)(connection, new_barrier);
 }

 TSAN_INTERCEPTOR(void, xpc_connection_send_message_with_reply,
                  xpc_connection_t connection, xpc_object_t message,
                  dispatch_queue_t replyq, xpc_handler_t handler) {
   SCOPED_TSAN_INTERCEPTOR(xpc_connection_send_message_with_reply, connection,
                           message, replyq, handler);
   Release(thr, pc, (uptr)connection);
   xpc_handler_t new_handler = ^(xpc_object_t object) {
     {
       SCOPED_INTERCEPTOR_RAW(xpc_connection_send_message_with_reply);
       Acquire(thr, pc, (uptr)connection);
     }
     handler(object);
   };
   REAL(xpc_connection_send_message_with_reply)
   (connection, message, replyq, new_handler);
 }

 // On macOS, libc++ is always linked dynamically, so intercepting works the
 // usual way.
 #define STDCXX_INTERCEPTOR TSAN_INTERCEPTOR

 namespace {
 struct fake_shared_weak_count {
   volatile a64 shared_owners;
   volatile a64 shared_weak_owners;
   virtual void _unused_0x0() = 0;
   virtual void _unused_0x8() = 0;
   virtual void on_zero_shared() = 0;
   virtual void _unused_0x18() = 0;
   virtual void on_zero_shared_weak() = 0;
 };
 }  // namespace

 // This adds a libc++ interceptor for:
 //     void __shared_weak_count::__release_shared() _NOEXCEPT;
 // Shared and weak pointers in C++ maintain reference counts via atomics in
 // libc++.dylib, which are TSan-invisible, and this leads to false positives in
 // destructor code.  This interceptor re-implements the whole function so that
 // the mo_acq_rel semantics of the atomic decrement are visible.
 //
 // Unfortunately, this interceptor cannot simply Acquire/Release some sync
 // object and call the original function, because it would have a race between
 // the sync and the destruction of the object.  Calling both under a lock will
 // not work because the destructor can invoke this interceptor again (and even
 // in a different thread, so recursive locks don't help).
 STDCXX_INTERCEPTOR(void, _ZNSt3__119__shared_weak_count16__release_sharedEv,
                    fake_shared_weak_count *o) {
   if (!flags()->shared_ptr_interceptor)
     return REAL(_ZNSt3__119__shared_weak_count16__release_sharedEv)(o);

   SCOPED_TSAN_INTERCEPTOR(_ZNSt3__119__shared_weak_count16__release_sharedEv,
                           o);
   if (__tsan_atomic64_fetch_add(&o->shared_owners, -1, mo_release) == 0) {
     Acquire(thr, pc, (uptr)&o->shared_owners);
     o->on_zero_shared();
     if (__tsan_atomic64_fetch_add(&o->shared_weak_owners, -1, mo_release) ==
         0) {
       Acquire(thr, pc, (uptr)&o->shared_weak_owners);
       o->on_zero_shared_weak();
     }
   }
 }

 }  // namespace __tsan

 #endif  // SANITIZER_MAC
	//===-- tsan_interceptors_mac.cc ------------------------------------------===//
	//
	// The LLVM Compiler Infrastructure
	//
	// This file is distributed under the University of Illinois Open Source
	// License. See LICENSE.TXT for details.
	//
	//===----------------------------------------------------------------------===//
	//
	// This file is a part of ThreadSanitizer (TSan), a race detector.
	//
	// Mac-specific interceptors.
	//===----------------------------------------------------------------------===//

	#include "sanitizer_common/sanitizer_platform.h"
	#if SANITIZER_MAC

	#include "interception/interception.h"
	#include "tsan_interceptors.h"
	#include "tsan_interface.h"
	#include "tsan_interface_ann.h"

	#include <libkern/OSAtomic.h>
	#include <xpc/xpc.h>

	typedef long long_t; // NOLINT

	namespace __tsan {

	// The non-barrier versions of OSAtomic* functions are semantically mo_relaxed,
	// but the two variants (e.g. OSAtomicAdd32 and OSAtomicAdd32Barrier) are
	// actually aliases of each other, and we cannot have different interceptors for
	// them, because they're actually the same function. Thus, we have to stay
	// conservative and treat the non-barrier versions as mo_acq_rel.
	static const morder kMacOrderBarrier = mo_acq_rel;
	static const morder kMacOrderNonBarrier = mo_acq_rel;

	#define OSATOMIC_INTERCEPTOR(return_t, t, tsan_t, f, tsan_atomic_f, mo) \
	TSAN_INTERCEPTOR(return_t, f, t x, volatile t *ptr) { \
	SCOPED_TSAN_INTERCEPTOR(f, x, ptr); \
	return tsan_atomic_f((volatile tsan_t *)ptr, x, mo); \
	}

	#define OSATOMIC_INTERCEPTOR_PLUS_X(return_t, t, tsan_t, f, tsan_atomic_f, mo) \
	TSAN_INTERCEPTOR(return_t, f, t x, volatile t *ptr) { \
	SCOPED_TSAN_INTERCEPTOR(f, x, ptr); \
	return tsan_atomic_f((volatile tsan_t *)ptr, x, mo) + x; \
	}

	#define OSATOMIC_INTERCEPTOR_PLUS_1(return_t, t, tsan_t, f, tsan_atomic_f, mo) \
	TSAN_INTERCEPTOR(return_t, f, volatile t *ptr) { \
	SCOPED_TSAN_INTERCEPTOR(f, ptr); \
	return tsan_atomic_f((volatile tsan_t *)ptr, 1, mo) + 1; \
	}

	#define OSATOMIC_INTERCEPTOR_MINUS_1(return_t, t, tsan_t, f, tsan_atomic_f, \
	mo) \
	TSAN_INTERCEPTOR(return_t, f, volatile t *ptr) { \
	SCOPED_TSAN_INTERCEPTOR(f, ptr); \
	return tsan_atomic_f((volatile tsan_t *)ptr, 1, mo) - 1; \
	}

	#define OSATOMIC_INTERCEPTORS_ARITHMETIC(f, tsan_atomic_f, m) \
	m(int32_t, int32_t, a32, f##32, __tsan_atomic32_##tsan_atomic_f, \
	kMacOrderNonBarrier) \
	m(int32_t, int32_t, a32, f##32##Barrier, __tsan_atomic32_##tsan_atomic_f, \
	kMacOrderBarrier) \
	m(int64_t, int64_t, a64, f##64, __tsan_atomic64_##tsan_atomic_f, \
	kMacOrderNonBarrier) \
	m(int64_t, int64_t, a64, f##64##Barrier, __tsan_atomic64_##tsan_atomic_f, \
	kMacOrderBarrier)

	#define OSATOMIC_INTERCEPTORS_BITWISE(f, tsan_atomic_f, m, m_orig) \
	m(int32_t, uint32_t, a32, f##32, __tsan_atomic32_##tsan_atomic_f, \
	kMacOrderNonBarrier) \
	m(int32_t, uint32_t, a32, f##32##Barrier, __tsan_atomic32_##tsan_atomic_f, \
	kMacOrderBarrier) \
	m_orig(int32_t, uint32_t, a32, f##32##Orig, __tsan_atomic32_##tsan_atomic_f, \
	kMacOrderNonBarrier) \
	m_orig(int32_t, uint32_t, a32, f##32##OrigBarrier, \
	__tsan_atomic32_##tsan_atomic_f, kMacOrderBarrier)

	OSATOMIC_INTERCEPTORS_ARITHMETIC(OSAtomicAdd, fetch_add,
	OSATOMIC_INTERCEPTOR_PLUS_X)
	OSATOMIC_INTERCEPTORS_ARITHMETIC(OSAtomicIncrement, fetch_add,
	OSATOMIC_INTERCEPTOR_PLUS_1)
	OSATOMIC_INTERCEPTORS_ARITHMETIC(OSAtomicDecrement, fetch_sub,
	OSATOMIC_INTERCEPTOR_MINUS_1)
	OSATOMIC_INTERCEPTORS_BITWISE(OSAtomicOr, fetch_or, OSATOMIC_INTERCEPTOR_PLUS_X,
	OSATOMIC_INTERCEPTOR)
	OSATOMIC_INTERCEPTORS_BITWISE(OSAtomicAnd, fetch_and,
	OSATOMIC_INTERCEPTOR_PLUS_X, OSATOMIC_INTERCEPTOR)
	OSATOMIC_INTERCEPTORS_BITWISE(OSAtomicXor, fetch_xor,
	OSATOMIC_INTERCEPTOR_PLUS_X, OSATOMIC_INTERCEPTOR)

	#define OSATOMIC_INTERCEPTORS_CAS(f, tsan_atomic_f, tsan_t, t) \
	TSAN_INTERCEPTOR(bool, f, t old_value, t new_value, t volatile *ptr) { \
	SCOPED_TSAN_INTERCEPTOR(f, old_value, new_value, ptr); \
	return tsan_atomic_f##_compare_exchange_strong( \
	(tsan_t )ptr, (tsan_t )&old_value, (tsan_t)new_value, \
	kMacOrderNonBarrier, kMacOrderNonBarrier); \
	} \
	\
	TSAN_INTERCEPTOR(bool, f##Barrier, t old_value, t new_value, \
	t volatile *ptr) { \
	SCOPED_TSAN_INTERCEPTOR(f##Barrier, old_value, new_value, ptr); \
	return tsan_atomic_f##_compare_exchange_strong( \
	(tsan_t )ptr, (tsan_t )&old_value, (tsan_t)new_value, \
	kMacOrderBarrier, kMacOrderNonBarrier); \
	}

	OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwapInt, __tsan_atomic32, a32, int)
	OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwapLong, __tsan_atomic64, a64,
	long_t)
	OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwapPtr, __tsan_atomic64, a64,
	void *)
	OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwap32, __tsan_atomic32, a32,
	int32_t)
	OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwap64, __tsan_atomic64, a64,
	int64_t)

	#define OSATOMIC_INTERCEPTOR_BITOP(f, op, m, mo) \
	TSAN_INTERCEPTOR(bool, f, uint32_t n, volatile void *ptr) { \
	SCOPED_TSAN_INTERCEPTOR(f, n, ptr); \
	char byte_ptr = ((char )ptr) + (n >> 3); \
	char bit_index = n & 7; \
	char mask = m; \
	char orig_byte = op((a8 *)byte_ptr, mask, mo); \
	return orig_byte & mask; \
	}

	#define OSATOMIC_INTERCEPTORS_BITOP(f, op, m) \
	OSATOMIC_INTERCEPTOR_BITOP(f, op, m, kMacOrderNonBarrier) \
	OSATOMIC_INTERCEPTOR_BITOP(f##Barrier, op, m, kMacOrderBarrier)

	OSATOMIC_INTERCEPTORS_BITOP(OSAtomicTestAndSet, __tsan_atomic8_fetch_or,
	0x80u >> bit_index)
	OSATOMIC_INTERCEPTORS_BITOP(OSAtomicTestAndClear, __tsan_atomic8_fetch_and,
	~(0x80u >> bit_index))

	TSAN_INTERCEPTOR(void, OSAtomicEnqueue, OSQueueHead list, void item,
	size_t offset) {
	SCOPED_TSAN_INTERCEPTOR(OSAtomicEnqueue, list, item, offset);
	__tsan_release(item);
	REAL(OSAtomicEnqueue)(list, item, offset);
	}

	TSAN_INTERCEPTOR(void , OSAtomicDequeue, OSQueueHead list, size_t offset) {
	SCOPED_TSAN_INTERCEPTOR(OSAtomicDequeue, list, offset);
	void *item = REAL(OSAtomicDequeue)(list, offset);
	if (item) __tsan_acquire(item);
	return item;
	}

	// OSAtomicFifoEnqueue and OSAtomicFifoDequeue are only on OS X.
	#if !SANITIZER_IOS

	TSAN_INTERCEPTOR(void, OSAtomicFifoEnqueue, OSFifoQueueHead list, void item,
	size_t offset) {
	SCOPED_TSAN_INTERCEPTOR(OSAtomicFifoEnqueue, list, item, offset);
	__tsan_release(item);
	REAL(OSAtomicFifoEnqueue)(list, item, offset);
	}

	TSAN_INTERCEPTOR(void , OSAtomicFifoDequeue, OSFifoQueueHead list,
	size_t offset) {
	SCOPED_TSAN_INTERCEPTOR(OSAtomicFifoDequeue, list, offset);
	void *item = REAL(OSAtomicFifoDequeue)(list, offset);
	if (item) __tsan_acquire(item);
	return item;
	}

	#endif

	TSAN_INTERCEPTOR(void, OSSpinLockLock, volatile OSSpinLock *lock) {
	CHECK(!cur_thread()->is_dead);
	if (!cur_thread()->is_inited) {
	return REAL(OSSpinLockLock)(lock);
	}
	SCOPED_TSAN_INTERCEPTOR(OSSpinLockLock, lock);
	REAL(OSSpinLockLock)(lock);
	Acquire(thr, pc, (uptr)lock);
	}

	TSAN_INTERCEPTOR(bool, OSSpinLockTry, volatile OSSpinLock *lock) {
	CHECK(!cur_thread()->is_dead);
	if (!cur_thread()->is_inited) {
	return REAL(OSSpinLockTry)(lock);
	}
	SCOPED_TSAN_INTERCEPTOR(OSSpinLockTry, lock);
	bool result = REAL(OSSpinLockTry)(lock);
	if (result)
	Acquire(thr, pc, (uptr)lock);
	return result;
	}

	TSAN_INTERCEPTOR(void, OSSpinLockUnlock, volatile OSSpinLock *lock) {
	CHECK(!cur_thread()->is_dead);
	if (!cur_thread()->is_inited) {
	return REAL(OSSpinLockUnlock)(lock);
	}
	SCOPED_TSAN_INTERCEPTOR(OSSpinLockUnlock, lock);
	Release(thr, pc, (uptr)lock);
	REAL(OSSpinLockUnlock)(lock);
	}

	TSAN_INTERCEPTOR(void, os_lock_lock, void *lock) {
	CHECK(!cur_thread()->is_dead);
	if (!cur_thread()->is_inited) {
	return REAL(os_lock_lock)(lock);
	}
	SCOPED_TSAN_INTERCEPTOR(os_lock_lock, lock);
	REAL(os_lock_lock)(lock);
	Acquire(thr, pc, (uptr)lock);
	}

	TSAN_INTERCEPTOR(bool, os_lock_trylock, void *lock) {
	CHECK(!cur_thread()->is_dead);
	if (!cur_thread()->is_inited) {
	return REAL(os_lock_trylock)(lock);
	}
	SCOPED_TSAN_INTERCEPTOR(os_lock_trylock, lock);
	bool result = REAL(os_lock_trylock)(lock);
	if (result)
	Acquire(thr, pc, (uptr)lock);
	return result;
	}

	TSAN_INTERCEPTOR(void, os_lock_unlock, void *lock) {
	CHECK(!cur_thread()->is_dead);
	if (!cur_thread()->is_inited) {
	return REAL(os_lock_unlock)(lock);
	}
	SCOPED_TSAN_INTERCEPTOR(os_lock_unlock, lock);
	Release(thr, pc, (uptr)lock);
	REAL(os_lock_unlock)(lock);
	}

	TSAN_INTERCEPTOR(void, xpc_connection_set_event_handler,
	xpc_connection_t connection, xpc_handler_t handler) {
	SCOPED_TSAN_INTERCEPTOR(xpc_connection_set_event_handler, connection,
	handler);
	Release(thr, pc, (uptr)connection);
	xpc_handler_t new_handler = ^(xpc_object_t object) {
	{
	SCOPED_INTERCEPTOR_RAW(xpc_connection_set_event_handler);
	Acquire(thr, pc, (uptr)connection);
	}
	handler(object);
	};
	REAL(xpc_connection_set_event_handler)(connection, new_handler);
	}

	TSAN_INTERCEPTOR(void, xpc_connection_send_barrier, xpc_connection_t connection,
	dispatch_block_t barrier) {
	SCOPED_TSAN_INTERCEPTOR(xpc_connection_send_barrier, connection, barrier);
	Release(thr, pc, (uptr)connection);
	dispatch_block_t new_barrier = ^() {
	{
	SCOPED_INTERCEPTOR_RAW(xpc_connection_send_barrier);
	Acquire(thr, pc, (uptr)connection);
	}
	barrier();
	};
	REAL(xpc_connection_send_barrier)(connection, new_barrier);
	}

	TSAN_INTERCEPTOR(void, xpc_connection_send_message_with_reply,
	xpc_connection_t connection, xpc_object_t message,
	dispatch_queue_t replyq, xpc_handler_t handler) {
	SCOPED_TSAN_INTERCEPTOR(xpc_connection_send_message_with_reply, connection,
	message, replyq, handler);
	Release(thr, pc, (uptr)connection);
	xpc_handler_t new_handler = ^(xpc_object_t object) {
	{
	SCOPED_INTERCEPTOR_RAW(xpc_connection_send_message_with_reply);
	Acquire(thr, pc, (uptr)connection);
	}
	handler(object);
	};
	REAL(xpc_connection_send_message_with_reply)
	(connection, message, replyq, new_handler);
	}

	// On macOS, libc++ is always linked dynamically, so intercepting works the
	// usual way.
	#define STDCXX_INTERCEPTOR TSAN_INTERCEPTOR

	namespace {
	struct fake_shared_weak_count {
	volatile a64 shared_owners;
	volatile a64 shared_weak_owners;
	virtual void _unused_0x0() = 0;
	virtual void _unused_0x8() = 0;
	virtual void on_zero_shared() = 0;
	virtual void _unused_0x18() = 0;
	virtual void on_zero_shared_weak() = 0;
	};
	} // namespace

	// This adds a libc++ interceptor for:
	// void __shared_weak_count::__release_shared() _NOEXCEPT;
	// Shared and weak pointers in C++ maintain reference counts via atomics in
	// libc++.dylib, which are TSan-invisible, and this leads to false positives in
	// destructor code. This interceptor re-implements the whole function so that
	// the mo_acq_rel semantics of the atomic decrement are visible.
	//
	// Unfortunately, this interceptor cannot simply Acquire/Release some sync
	// object and call the original function, because it would have a race between
	// the sync and the destruction of the object. Calling both under a lock will
	// not work because the destructor can invoke this interceptor again (and even
	// in a different thread, so recursive locks don't help).
	STDCXX_INTERCEPTOR(void, _ZNSt3__119__shared_weak_count16__release_sharedEv,
	fake_shared_weak_count *o) {
	if (!flags()->shared_ptr_interceptor)
	return REAL(_ZNSt3__119__shared_weak_count16__release_sharedEv)(o);

	SCOPED_TSAN_INTERCEPTOR(_ZNSt3__119__shared_weak_count16__release_sharedEv,
	o);
	if (__tsan_atomic64_fetch_add(&o->shared_owners, -1, mo_release) == 0) {
	Acquire(thr, pc, (uptr)&o->shared_owners);
	o->on_zero_shared();
	if (__tsan_atomic64_fetch_add(&o->shared_weak_owners, -1, mo_release) ==
	0) {
	Acquire(thr, pc, (uptr)&o->shared_weak_owners);
	o->on_zero_shared_weak();
	}
	}
	}

	} // namespace __tsan

	#endif // SANITIZER_MAC