521 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			521 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===-- tsan_interceptors_mac.cpp -----------------------------------------===//
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| //
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| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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| // See https://llvm.org/LICENSE.txt for license information.
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| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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| //
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| //===----------------------------------------------------------------------===//
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| //
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| // This file is a part of ThreadSanitizer (TSan), a race detector.
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| //
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| // Mac-specific interceptors.
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| //===----------------------------------------------------------------------===//
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| 
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| #include "sanitizer_common/sanitizer_platform.h"
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| #if SANITIZER_MAC
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| 
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| #include "interception/interception.h"
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| #include "tsan_interceptors.h"
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| #include "tsan_interface.h"
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| #include "tsan_interface_ann.h"
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| #include "sanitizer_common/sanitizer_addrhashmap.h"
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| 
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| #include <errno.h>
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| #include <libkern/OSAtomic.h>
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| #include <objc/objc-sync.h>
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| #include <os/lock.h>
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| #include <sys/ucontext.h>
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| 
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| #if defined(__has_include) && __has_include(<xpc/xpc.h>)
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| #include <xpc/xpc.h>
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| #endif  // #if defined(__has_include) && __has_include(<xpc/xpc.h>)
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| 
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| typedef long long_t;
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| 
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| extern "C" {
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| int getcontext(ucontext_t *ucp) __attribute__((returns_twice));
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| int setcontext(const ucontext_t *ucp);
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| }
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| 
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| namespace __tsan {
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| 
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| // The non-barrier versions of OSAtomic* functions are semantically mo_relaxed,
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| // but the two variants (e.g. OSAtomicAdd32 and OSAtomicAdd32Barrier) are
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| // actually aliases of each other, and we cannot have different interceptors for
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| // them, because they're actually the same function.  Thus, we have to stay
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| // conservative and treat the non-barrier versions as mo_acq_rel.
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| static const morder kMacOrderBarrier = mo_acq_rel;
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| static const morder kMacOrderNonBarrier = mo_acq_rel;
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| 
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| #define OSATOMIC_INTERCEPTOR(return_t, t, tsan_t, f, tsan_atomic_f, mo) \
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|   TSAN_INTERCEPTOR(return_t, f, t x, volatile t *ptr) {                 \
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|     SCOPED_TSAN_INTERCEPTOR(f, x, ptr);                                 \
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|     return tsan_atomic_f((volatile tsan_t *)ptr, x, mo);                \
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|   }
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| 
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| #define OSATOMIC_INTERCEPTOR_PLUS_X(return_t, t, tsan_t, f, tsan_atomic_f, mo) \
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|   TSAN_INTERCEPTOR(return_t, f, t x, volatile t *ptr) {                        \
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|     SCOPED_TSAN_INTERCEPTOR(f, x, ptr);                                        \
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|     return tsan_atomic_f((volatile tsan_t *)ptr, x, mo) + x;                   \
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|   }
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| 
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| #define OSATOMIC_INTERCEPTOR_PLUS_1(return_t, t, tsan_t, f, tsan_atomic_f, mo) \
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|   TSAN_INTERCEPTOR(return_t, f, volatile t *ptr) {                             \
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|     SCOPED_TSAN_INTERCEPTOR(f, ptr);                                           \
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|     return tsan_atomic_f((volatile tsan_t *)ptr, 1, mo) + 1;                   \
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|   }
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| 
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| #define OSATOMIC_INTERCEPTOR_MINUS_1(return_t, t, tsan_t, f, tsan_atomic_f, \
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|                                      mo)                                    \
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|   TSAN_INTERCEPTOR(return_t, f, volatile t *ptr) {                          \
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|     SCOPED_TSAN_INTERCEPTOR(f, ptr);                                        \
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|     return tsan_atomic_f((volatile tsan_t *)ptr, 1, mo) - 1;                \
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|   }
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| 
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| #define OSATOMIC_INTERCEPTORS_ARITHMETIC(f, tsan_atomic_f, m)                  \
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|   m(int32_t, int32_t, a32, f##32, __tsan_atomic32_##tsan_atomic_f,             \
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|     kMacOrderNonBarrier)                                                       \
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|   m(int32_t, int32_t, a32, f##32##Barrier, __tsan_atomic32_##tsan_atomic_f,    \
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|     kMacOrderBarrier)                                                          \
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|   m(int64_t, int64_t, a64, f##64, __tsan_atomic64_##tsan_atomic_f,             \
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|     kMacOrderNonBarrier)                                                       \
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|   m(int64_t, int64_t, a64, f##64##Barrier, __tsan_atomic64_##tsan_atomic_f,    \
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|     kMacOrderBarrier)
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| 
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| #define OSATOMIC_INTERCEPTORS_BITWISE(f, tsan_atomic_f, m, m_orig)             \
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|   m(int32_t, uint32_t, a32, f##32, __tsan_atomic32_##tsan_atomic_f,            \
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|     kMacOrderNonBarrier)                                                       \
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|   m(int32_t, uint32_t, a32, f##32##Barrier, __tsan_atomic32_##tsan_atomic_f,   \
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|     kMacOrderBarrier)                                                          \
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|   m_orig(int32_t, uint32_t, a32, f##32##Orig, __tsan_atomic32_##tsan_atomic_f, \
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|     kMacOrderNonBarrier)                                                       \
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|   m_orig(int32_t, uint32_t, a32, f##32##OrigBarrier,                           \
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|     __tsan_atomic32_##tsan_atomic_f, kMacOrderBarrier)
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| 
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| OSATOMIC_INTERCEPTORS_ARITHMETIC(OSAtomicAdd, fetch_add,
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|                                  OSATOMIC_INTERCEPTOR_PLUS_X)
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| OSATOMIC_INTERCEPTORS_ARITHMETIC(OSAtomicIncrement, fetch_add,
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|                                  OSATOMIC_INTERCEPTOR_PLUS_1)
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| OSATOMIC_INTERCEPTORS_ARITHMETIC(OSAtomicDecrement, fetch_sub,
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|                                  OSATOMIC_INTERCEPTOR_MINUS_1)
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| OSATOMIC_INTERCEPTORS_BITWISE(OSAtomicOr, fetch_or, OSATOMIC_INTERCEPTOR_PLUS_X,
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|                               OSATOMIC_INTERCEPTOR)
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| OSATOMIC_INTERCEPTORS_BITWISE(OSAtomicAnd, fetch_and,
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|                               OSATOMIC_INTERCEPTOR_PLUS_X, OSATOMIC_INTERCEPTOR)
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| OSATOMIC_INTERCEPTORS_BITWISE(OSAtomicXor, fetch_xor,
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|                               OSATOMIC_INTERCEPTOR_PLUS_X, OSATOMIC_INTERCEPTOR)
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| 
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| #define OSATOMIC_INTERCEPTORS_CAS(f, tsan_atomic_f, tsan_t, t)              \
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|   TSAN_INTERCEPTOR(bool, f, t old_value, t new_value, t volatile *ptr) {    \
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|     SCOPED_TSAN_INTERCEPTOR(f, old_value, new_value, ptr);                  \
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|     return tsan_atomic_f##_compare_exchange_strong(                         \
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|         (volatile tsan_t *)ptr, (tsan_t *)&old_value, (tsan_t)new_value,    \
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|         kMacOrderNonBarrier, kMacOrderNonBarrier);                          \
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|   }                                                                         \
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|                                                                             \
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|   TSAN_INTERCEPTOR(bool, f##Barrier, t old_value, t new_value,              \
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|                    t volatile *ptr) {                                       \
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|     SCOPED_TSAN_INTERCEPTOR(f##Barrier, old_value, new_value, ptr);         \
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|     return tsan_atomic_f##_compare_exchange_strong(                         \
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|         (volatile tsan_t *)ptr, (tsan_t *)&old_value, (tsan_t)new_value,    \
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|         kMacOrderBarrier, kMacOrderNonBarrier);                             \
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|   }
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| 
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| OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwapInt, __tsan_atomic32, a32, int)
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| OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwapLong, __tsan_atomic64, a64,
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|                           long_t)
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| OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwapPtr, __tsan_atomic64, a64,
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|                           void *)
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| OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwap32, __tsan_atomic32, a32,
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|                           int32_t)
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| OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwap64, __tsan_atomic64, a64,
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|                           int64_t)
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| 
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| #define OSATOMIC_INTERCEPTOR_BITOP(f, op, clear, mo)             \
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|   TSAN_INTERCEPTOR(bool, f, uint32_t n, volatile void *ptr) {    \
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|     SCOPED_TSAN_INTERCEPTOR(f, n, ptr);                          \
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|     volatile char *byte_ptr = ((volatile char *)ptr) + (n >> 3); \
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|     char bit = 0x80u >> (n & 7);                                 \
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|     char mask = clear ? ~bit : bit;                              \
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|     char orig_byte = op((volatile a8 *)byte_ptr, mask, mo);      \
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|     return orig_byte & bit;                                      \
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|   }
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| 
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| #define OSATOMIC_INTERCEPTORS_BITOP(f, op, clear)               \
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|   OSATOMIC_INTERCEPTOR_BITOP(f, op, clear, kMacOrderNonBarrier) \
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|   OSATOMIC_INTERCEPTOR_BITOP(f##Barrier, op, clear, kMacOrderBarrier)
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| 
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| OSATOMIC_INTERCEPTORS_BITOP(OSAtomicTestAndSet, __tsan_atomic8_fetch_or, false)
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| OSATOMIC_INTERCEPTORS_BITOP(OSAtomicTestAndClear, __tsan_atomic8_fetch_and,
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|                             true)
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| 
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| TSAN_INTERCEPTOR(void, OSAtomicEnqueue, OSQueueHead *list, void *item,
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|                  size_t offset) {
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|   SCOPED_TSAN_INTERCEPTOR(OSAtomicEnqueue, list, item, offset);
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|   __tsan_release(item);
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|   REAL(OSAtomicEnqueue)(list, item, offset);
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| }
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| 
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| TSAN_INTERCEPTOR(void *, OSAtomicDequeue, OSQueueHead *list, size_t offset) {
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|   SCOPED_TSAN_INTERCEPTOR(OSAtomicDequeue, list, offset);
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|   void *item = REAL(OSAtomicDequeue)(list, offset);
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|   if (item) __tsan_acquire(item);
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|   return item;
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| }
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| 
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| // OSAtomicFifoEnqueue and OSAtomicFifoDequeue are only on OS X.
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| #if !SANITIZER_IOS
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| 
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| TSAN_INTERCEPTOR(void, OSAtomicFifoEnqueue, OSFifoQueueHead *list, void *item,
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|                  size_t offset) {
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|   SCOPED_TSAN_INTERCEPTOR(OSAtomicFifoEnqueue, list, item, offset);
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|   __tsan_release(item);
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|   REAL(OSAtomicFifoEnqueue)(list, item, offset);
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| }
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| 
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| TSAN_INTERCEPTOR(void *, OSAtomicFifoDequeue, OSFifoQueueHead *list,
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|                  size_t offset) {
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|   SCOPED_TSAN_INTERCEPTOR(OSAtomicFifoDequeue, list, offset);
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|   void *item = REAL(OSAtomicFifoDequeue)(list, offset);
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|   if (item) __tsan_acquire(item);
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|   return item;
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| }
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| 
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| #endif
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| 
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| TSAN_INTERCEPTOR(void, OSSpinLockLock, volatile OSSpinLock *lock) {
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|   CHECK(!cur_thread()->is_dead);
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|   if (!cur_thread()->is_inited) {
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|     return REAL(OSSpinLockLock)(lock);
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|   }
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|   SCOPED_TSAN_INTERCEPTOR(OSSpinLockLock, lock);
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|   REAL(OSSpinLockLock)(lock);
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|   Acquire(thr, pc, (uptr)lock);
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| }
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| 
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| TSAN_INTERCEPTOR(bool, OSSpinLockTry, volatile OSSpinLock *lock) {
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|   CHECK(!cur_thread()->is_dead);
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|   if (!cur_thread()->is_inited) {
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|     return REAL(OSSpinLockTry)(lock);
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|   }
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|   SCOPED_TSAN_INTERCEPTOR(OSSpinLockTry, lock);
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|   bool result = REAL(OSSpinLockTry)(lock);
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|   if (result)
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|     Acquire(thr, pc, (uptr)lock);
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|   return result;
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| }
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| 
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| TSAN_INTERCEPTOR(void, OSSpinLockUnlock, volatile OSSpinLock *lock) {
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|   CHECK(!cur_thread()->is_dead);
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|   if (!cur_thread()->is_inited) {
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|     return REAL(OSSpinLockUnlock)(lock);
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|   }
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|   SCOPED_TSAN_INTERCEPTOR(OSSpinLockUnlock, lock);
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|   Release(thr, pc, (uptr)lock);
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|   REAL(OSSpinLockUnlock)(lock);
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| }
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| 
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| TSAN_INTERCEPTOR(void, os_lock_lock, void *lock) {
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|   CHECK(!cur_thread()->is_dead);
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|   if (!cur_thread()->is_inited) {
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|     return REAL(os_lock_lock)(lock);
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|   }
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|   SCOPED_TSAN_INTERCEPTOR(os_lock_lock, lock);
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|   REAL(os_lock_lock)(lock);
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|   Acquire(thr, pc, (uptr)lock);
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| }
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| 
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| TSAN_INTERCEPTOR(bool, os_lock_trylock, void *lock) {
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|   CHECK(!cur_thread()->is_dead);
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|   if (!cur_thread()->is_inited) {
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|     return REAL(os_lock_trylock)(lock);
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|   }
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|   SCOPED_TSAN_INTERCEPTOR(os_lock_trylock, lock);
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|   bool result = REAL(os_lock_trylock)(lock);
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|   if (result)
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|     Acquire(thr, pc, (uptr)lock);
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|   return result;
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| }
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| 
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| TSAN_INTERCEPTOR(void, os_lock_unlock, void *lock) {
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|   CHECK(!cur_thread()->is_dead);
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|   if (!cur_thread()->is_inited) {
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|     return REAL(os_lock_unlock)(lock);
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|   }
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|   SCOPED_TSAN_INTERCEPTOR(os_lock_unlock, lock);
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|   Release(thr, pc, (uptr)lock);
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|   REAL(os_lock_unlock)(lock);
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| }
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| 
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| TSAN_INTERCEPTOR(void, os_unfair_lock_lock, os_unfair_lock_t lock) {
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|   if (!cur_thread()->is_inited || cur_thread()->is_dead) {
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|     return REAL(os_unfair_lock_lock)(lock);
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|   }
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|   SCOPED_TSAN_INTERCEPTOR(os_unfair_lock_lock, lock);
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|   REAL(os_unfair_lock_lock)(lock);
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|   Acquire(thr, pc, (uptr)lock);
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| }
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| 
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| TSAN_INTERCEPTOR(void, os_unfair_lock_lock_with_options, os_unfair_lock_t lock,
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|                  u32 options) {
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|   if (!cur_thread()->is_inited || cur_thread()->is_dead) {
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|     return REAL(os_unfair_lock_lock_with_options)(lock, options);
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|   }
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|   SCOPED_TSAN_INTERCEPTOR(os_unfair_lock_lock_with_options, lock, options);
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|   REAL(os_unfair_lock_lock_with_options)(lock, options);
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|   Acquire(thr, pc, (uptr)lock);
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| }
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| 
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| TSAN_INTERCEPTOR(bool, os_unfair_lock_trylock, os_unfair_lock_t lock) {
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|   if (!cur_thread()->is_inited || cur_thread()->is_dead) {
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|     return REAL(os_unfair_lock_trylock)(lock);
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|   }
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|   SCOPED_TSAN_INTERCEPTOR(os_unfair_lock_trylock, lock);
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|   bool result = REAL(os_unfair_lock_trylock)(lock);
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|   if (result)
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|     Acquire(thr, pc, (uptr)lock);
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|   return result;
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| }
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| 
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| TSAN_INTERCEPTOR(void, os_unfair_lock_unlock, os_unfair_lock_t lock) {
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|   if (!cur_thread()->is_inited || cur_thread()->is_dead) {
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|     return REAL(os_unfair_lock_unlock)(lock);
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|   }
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|   SCOPED_TSAN_INTERCEPTOR(os_unfair_lock_unlock, lock);
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|   Release(thr, pc, (uptr)lock);
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|   REAL(os_unfair_lock_unlock)(lock);
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| }
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| 
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| #if defined(__has_include) && __has_include(<xpc/xpc.h>)
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| 
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| TSAN_INTERCEPTOR(void, xpc_connection_set_event_handler,
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|                  xpc_connection_t connection, xpc_handler_t handler) {
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|   SCOPED_TSAN_INTERCEPTOR(xpc_connection_set_event_handler, connection,
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|                           handler);
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|   Release(thr, pc, (uptr)connection);
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|   xpc_handler_t new_handler = ^(xpc_object_t object) {
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|     {
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|       SCOPED_INTERCEPTOR_RAW(xpc_connection_set_event_handler);
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|       Acquire(thr, pc, (uptr)connection);
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|     }
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|     handler(object);
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|   };
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|   REAL(xpc_connection_set_event_handler)(connection, new_handler);
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| }
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| 
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| TSAN_INTERCEPTOR(void, xpc_connection_send_barrier, xpc_connection_t connection,
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|                  dispatch_block_t barrier) {
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|   SCOPED_TSAN_INTERCEPTOR(xpc_connection_send_barrier, connection, barrier);
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|   Release(thr, pc, (uptr)connection);
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|   dispatch_block_t new_barrier = ^() {
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|     {
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|       SCOPED_INTERCEPTOR_RAW(xpc_connection_send_barrier);
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|       Acquire(thr, pc, (uptr)connection);
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|     }
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|     barrier();
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|   };
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|   REAL(xpc_connection_send_barrier)(connection, new_barrier);
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| }
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| 
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| TSAN_INTERCEPTOR(void, xpc_connection_send_message_with_reply,
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|                  xpc_connection_t connection, xpc_object_t message,
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|                  dispatch_queue_t replyq, xpc_handler_t handler) {
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|   SCOPED_TSAN_INTERCEPTOR(xpc_connection_send_message_with_reply, connection,
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|                           message, replyq, handler);
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|   Release(thr, pc, (uptr)connection);
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|   xpc_handler_t new_handler = ^(xpc_object_t object) {
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|     {
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|       SCOPED_INTERCEPTOR_RAW(xpc_connection_send_message_with_reply);
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|       Acquire(thr, pc, (uptr)connection);
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|     }
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|     handler(object);
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|   };
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|   REAL(xpc_connection_send_message_with_reply)
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|   (connection, message, replyq, new_handler);
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| }
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| 
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| TSAN_INTERCEPTOR(void, xpc_connection_cancel, xpc_connection_t connection) {
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|   SCOPED_TSAN_INTERCEPTOR(xpc_connection_cancel, connection);
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|   Release(thr, pc, (uptr)connection);
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|   REAL(xpc_connection_cancel)(connection);
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| }
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| 
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| #endif  // #if defined(__has_include) && __has_include(<xpc/xpc.h>)
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| 
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| // Determines whether the Obj-C object pointer is a tagged pointer. Tagged
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| // pointers encode the object data directly in their pointer bits and do not
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| // have an associated memory allocation. The Obj-C runtime uses tagged pointers
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| // to transparently optimize small objects.
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| static bool IsTaggedObjCPointer(id obj) {
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|   const uptr kPossibleTaggedBits = 0x8000000000000001ull;
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|   return ((uptr)obj & kPossibleTaggedBits) != 0;
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| }
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| 
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| // Returns an address which can be used to inform TSan about synchronization
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| // points (MutexLock/Unlock). The TSan infrastructure expects this to be a valid
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| // address in the process space. We do a small allocation here to obtain a
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| // stable address (the array backing the hash map can change). The memory is
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| // never free'd (leaked) and allocation and locking are slow, but this code only
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| // runs for @synchronized with tagged pointers, which is very rare.
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| static uptr GetOrCreateSyncAddress(uptr addr, ThreadState *thr, uptr pc) {
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|   typedef AddrHashMap<uptr, 5> Map;
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|   static Map Addresses;
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|   Map::Handle h(&Addresses, addr);
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|   if (h.created()) {
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|     ThreadIgnoreBegin(thr, pc);
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|     *h = (uptr) user_alloc(thr, pc, /*size=*/1);
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|     ThreadIgnoreEnd(thr, pc);
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|   }
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|   return *h;
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| }
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| 
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| // Returns an address on which we can synchronize given an Obj-C object pointer.
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| // For normal object pointers, this is just the address of the object in memory.
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| // Tagged pointers are not backed by an actual memory allocation, so we need to
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| // synthesize a valid address.
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| static uptr SyncAddressForObjCObject(id obj, ThreadState *thr, uptr pc) {
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|   if (IsTaggedObjCPointer(obj))
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|     return GetOrCreateSyncAddress((uptr)obj, thr, pc);
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|   return (uptr)obj;
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| }
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| 
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| TSAN_INTERCEPTOR(int, objc_sync_enter, id obj) {
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|   SCOPED_TSAN_INTERCEPTOR(objc_sync_enter, obj);
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|   if (!obj) return REAL(objc_sync_enter)(obj);
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|   uptr addr = SyncAddressForObjCObject(obj, thr, pc);
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|   MutexPreLock(thr, pc, addr, MutexFlagWriteReentrant);
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|   int result = REAL(objc_sync_enter)(obj);
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|   CHECK_EQ(result, OBJC_SYNC_SUCCESS);
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|   MutexPostLock(thr, pc, addr, MutexFlagWriteReentrant);
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|   return result;
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| }
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| 
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| TSAN_INTERCEPTOR(int, objc_sync_exit, id obj) {
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|   SCOPED_TSAN_INTERCEPTOR(objc_sync_exit, obj);
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|   if (!obj) return REAL(objc_sync_exit)(obj);
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|   uptr addr = SyncAddressForObjCObject(obj, thr, pc);
 | |
|   MutexUnlock(thr, pc, addr);
 | |
|   int result = REAL(objc_sync_exit)(obj);
 | |
|   if (result != OBJC_SYNC_SUCCESS) MutexInvalidAccess(thr, pc, addr);
 | |
|   return result;
 | |
| }
 | |
| 
 | |
| TSAN_INTERCEPTOR(int, swapcontext, ucontext_t *oucp, const ucontext_t *ucp) {
 | |
|   {
 | |
|     SCOPED_INTERCEPTOR_RAW(swapcontext, oucp, ucp);
 | |
|   }
 | |
|   // Bacause of swapcontext() semantics we have no option but to copy its
 | |
|   // impementation here
 | |
|   if (!oucp || !ucp) {
 | |
|     errno = EINVAL;
 | |
|     return -1;
 | |
|   }
 | |
|   ThreadState *thr = cur_thread();
 | |
|   const int UCF_SWAPPED = 0x80000000;
 | |
|   oucp->uc_onstack &= ~UCF_SWAPPED;
 | |
|   thr->ignore_interceptors++;
 | |
|   int ret = getcontext(oucp);
 | |
|   if (!(oucp->uc_onstack & UCF_SWAPPED)) {
 | |
|     thr->ignore_interceptors--;
 | |
|     if (!ret) {
 | |
|       oucp->uc_onstack |= UCF_SWAPPED;
 | |
|       ret = setcontext(ucp);
 | |
|     }
 | |
|   }
 | |
|   return ret;
 | |
| }
 | |
| 
 | |
| // 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;
 | |
|   virtual ~fake_shared_weak_count() = 0;  // suppress -Wnon-virtual-dtor
 | |
| };
 | |
| }  // namespace
 | |
| 
 | |
| // The following code adds libc++ interceptors for:
 | |
| //     void __shared_weak_count::__release_shared() _NOEXCEPT;
 | |
| //     bool __shared_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. These interceptors re-implements the whole functions so that
 | |
| // the mo_acq_rel semantics of the atomic decrement are visible.
 | |
| //
 | |
| // Unfortunately, the interceptors 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();
 | |
|     }
 | |
|   }
 | |
| }
 | |
| 
 | |
| STDCXX_INTERCEPTOR(bool, _ZNSt3__114__shared_count16__release_sharedEv,
 | |
|                    fake_shared_weak_count *o) {
 | |
|   if (!flags()->shared_ptr_interceptor)
 | |
|     return REAL(_ZNSt3__114__shared_count16__release_sharedEv)(o);
 | |
| 
 | |
|   SCOPED_TSAN_INTERCEPTOR(_ZNSt3__114__shared_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();
 | |
|     return true;
 | |
|   }
 | |
|   return false;
 | |
| }
 | |
| 
 | |
| namespace {
 | |
| struct call_once_callback_args {
 | |
|   void (*orig_func)(void *arg);
 | |
|   void *orig_arg;
 | |
|   void *flag;
 | |
| };
 | |
| 
 | |
| void call_once_callback_wrapper(void *arg) {
 | |
|   call_once_callback_args *new_args = (call_once_callback_args *)arg;
 | |
|   new_args->orig_func(new_args->orig_arg);
 | |
|   __tsan_release(new_args->flag);
 | |
| }
 | |
| }  // namespace
 | |
| 
 | |
| // This adds a libc++ interceptor for:
 | |
| //     void __call_once(volatile unsigned long&, void*, void(*)(void*));
 | |
| // C++11 call_once is implemented via an internal function __call_once which is
 | |
| // inside libc++.dylib, and the atomic release store inside it is thus
 | |
| // TSan-invisible. To avoid false positives, this interceptor wraps the callback
 | |
| // function and performs an explicit Release after the user code has run.
 | |
| STDCXX_INTERCEPTOR(void, _ZNSt3__111__call_onceERVmPvPFvS2_E, void *flag,
 | |
|                    void *arg, void (*func)(void *arg)) {
 | |
|   call_once_callback_args new_args = {func, arg, flag};
 | |
|   REAL(_ZNSt3__111__call_onceERVmPvPFvS2_E)(flag, &new_args,
 | |
|                                             call_once_callback_wrapper);
 | |
| }
 | |
| 
 | |
| }  // namespace __tsan
 | |
| 
 | |
| #endif  // SANITIZER_MAC
 |