diff options
Diffstat (limited to 'libatomic/cas_n.c')
-rw-r--r-- | libatomic/cas_n.c | 25 |
1 files changed, 12 insertions, 13 deletions
diff --git a/libatomic/cas_n.c b/libatomic/cas_n.c index a4702683899..fa5c0ada8c9 100644 --- a/libatomic/cas_n.c +++ b/libatomic/cas_n.c @@ -51,10 +51,9 @@ SIZE(libat_compare_exchange) (UTYPE *mptr, UTYPE *eptr, UTYPE newval, #if !DONE && N <= WORDSIZE && defined(atomic_compare_exchange_w) bool SIZE(libat_compare_exchange) (UTYPE *mptr, UTYPE *eptr, UTYPE newval, - int smodel, int fmodel UNUSED) + int smodel, int fmodel) { UWORD mask, shift, weval, woldval, wnewval, t, *wptr; - bool ret = false; pre_barrier (smodel); @@ -82,12 +81,13 @@ SIZE(libat_compare_exchange) (UTYPE *mptr, UTYPE *eptr, UTYPE newval, } while (!atomic_compare_exchange_w (wptr, &woldval, t, true, __ATOMIC_RELAXED, __ATOMIC_RELAXED)); - ret = true; + post_barrier (smodel); + return true; + failure: *eptr = woldval >> shift; - - post_barrier (smodel); - return ret; + post_barrier (fmodel); + return false; } #define DONE 1 @@ -102,18 +102,17 @@ SIZE(libat_compare_exchange) (UTYPE *mptr, UTYPE *eptr, UTYPE newval, { UTYPE oldval; UWORD magic; - bool ret = false; + bool ret; pre_seq_barrier (smodel); magic = protect_start (mptr); oldval = *mptr; - if (oldval == *eptr) - { - *mptr = newval; - ret = true; - } - *eptr = oldval; + ret = (oldval == *eptr); + if (ret) + *mptr = newval; + else + *eptr = oldval; protect_end (mptr, magic); post_seq_barrier (smodel); |