accel/tcg/user-retaddr.h


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#ifndef ACCEL_TCG_USER_RETADDR_H
#define ACCEL_TCG_USER_RETADDR_H

#include "qemu/atomic.h"

extern __thread uintptr_t helper_retaddr;

static inline void set_helper_retaddr(uintptr_t ra)
{
    helper_retaddr = ra;
    /*
     * Ensure that this write is visible to the SIGSEGV handler that
     * may be invoked due to a subsequent invalid memory operation.
     */
    signal_barrier();
}

static inline void clear_helper_retaddr(void)
{
    /*
     * Ensure that previous memory operations have succeeded before
     * removing the data visible to the signal handler.
     */
    signal_barrier();
    helper_retaddr = 0;
}

#endif