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#include <intrin.h> 
#include <cstdint> 
 
 
_LIBCPP_BEGIN_NAMESPACE_STD 
 
namespace { 
static const int __msvc_locks_size = 1024; 
volatile long __msvc_locks[__msvc_locks_size]; 
 
size_t __msvc_lock_hash(void* __p) { 
    uintptr_t __num = reinterpret_cast<uintptr_t>(__p); 
    return (__num ^ (__num >> 10)) & (__msvc_locks_size - 1); 
} 
} 
 
void __msvc_lock(void* __p) { 
    volatile long& __lock = __msvc_locks[__msvc_lock_hash(__p)]; 
    while (_InterlockedExchange(&__lock, 1) == 0) { 
#if defined(_M_ARM) || defined(_M_ARM64) 
        __yield(); 
#endif 
    } 
} 
 
void __msvc_unlock(void* __p) { 
    volatile long& __lock = __msvc_locks[__msvc_lock_hash(__p)]; 
    _InterlockedExchange(&__lock, 0); 
} 
 
_LIBCPP_END_NAMESPACE_STD