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#ifndef __LIBC_ATOMIC_H
#define __LIBC_ATOMIC_H
#include <stdatomic.h>
#define LIBC_LOCK(__lock) __libc_lock(&__lock)
#define LIBC_UNLOCK(__lock) atomic_flag_clear(&__lock)
static __inline void __libc_lock(volatile atomic_flag *lock)
{
while (atomic_flag_test_and_set_explicit(lock, memory_order_acquire)) {
unsigned int spins = 1;
do {
for (unsigned int i = 0; i < spins; i++)
__asm__ volatile("pause");
if (spins < 64)
spins *= 2;
} while (atomic_flag_test_and_set_explicit(
lock, memory_order_relaxed));
}
}
#endif
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