http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55561
--- Comment #32 from Joost VandeVondele <Joost.VandeVondele at mat dot ethz.ch>
2013-01-07 21:35:25 UTC ---
(In reply to comment #30)
> The formatting in the patch is wrong (multiple issues).
I've tried to fix them in the version below.
It would be really cool to have -fopenmp -fsanitize=thread to work
out-of-the-box with gcc.
2012-12-30 Dmitry Vyukov <dvyu...@gcc.gnu.org>
PR libgomp/55561
PR libgomp/40362
* config/linux/wait.h (do_spin): Use atomic load for addr.
* config/linux/ptrlock.c (gomp_ptrlock_get_slow): Use atomic
for intptr and ptrlock.
* onfig/linux/ptrlock.h (gomp_ptrlock_get): Use atomic load
for ptrlock.
Index: libgomp/config/linux/wait.h
===================================================================
--- libgomp/config/linux/wait.h (revision 194730)
+++ libgomp/config/linux/wait.h (working copy)
@@ -51,7 +51,7 @@ static inline int do_spin (int *addr, in
if (__builtin_expect (gomp_managed_threads > gomp_available_cpus, 0))
count = gomp_throttled_spin_count_var;
for (i = 0; i < count; i++)
- if (__builtin_expect (*addr != val, 0))
+ if (__builtin_expect (__atomic_load_n (addr, MEMMODEL_RELAXED) != val, 0))
return 0;
else
cpu_relax ();
Index: libgomp/config/linux/ptrlock.c
===================================================================
--- libgomp/config/linux/ptrlock.c (revision 194730)
+++ libgomp/config/linux/ptrlock.c (working copy)
@@ -50,9 +50,9 @@ gomp_ptrlock_get_slow (gomp_ptrlock_t *p
#endif
do
do_wait (intptr, 2);
- while (*intptr == 2);
+ while (__atomic_load_n (intptr, MEMMODEL_RELAXED) == 2);
__asm volatile ("" : : : "memory");
- return *ptrlock;
+ return (void *) __atomic_load_n (ptrlock, MEMMODEL_ACQUIRE);
}
void
Index: libgomp/config/linux/ptrlock.h
===================================================================
--- libgomp/config/linux/ptrlock.h (revision 194730)
+++ libgomp/config/linux/ptrlock.h (working copy)
@@ -48,8 +48,9 @@ static inline void *gomp_ptrlock_get (go
{
uintptr_t oldval;
- if ((uintptr_t) *ptrlock > 2)
- return *ptrlock;
+ uintptr_t v = (uintptr_t) __atomic_load_n (ptrlock, MEMMODEL_ACQUIRE);
+ if (v > 2)
+ return (void *) v;
oldval = 0;
if (__atomic_compare_exchange_n (ptrlock, &oldval, 1, false,
