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Re: Patch for PR libgomp/37938, IA64 specific.
On Thu, 2008-11-06 at 17:12 -0800, H.J. Lu wrote:
> static inline void gomp_mutex_unlock (gomp_mutex_t *mutex)
> {
> int val = __sync_lock_test_and_set (mutex, 0);
> if (__builtin_expect (val > 1, 0))
> gomp_mutex_unlock_slow (mutex);
> }
>
> should work as long as mutex isn't updated with release or
> unordered semantics prior to this function call. Who else
> have updated mutux? What semantics are they using?
Isn't the lock done with release semantics? gomp_mutex_lock
calls __sync_bool_compare_and_swap and sync_compare_and_swap<mode> in
sync.md generates a cmpxchg.rel instruction.
Steve Ellcey
sje@cup.hp.com