From 8f12da979523f5f95190d41fcef7e833b773a92d Mon Sep 17 00:00:00 2001 From: Maxim Kuvyrkov Date: Mon, 13 Aug 2012 19:55:34 -0700 Subject: Add explicit acquire/release semantics to MIPS' atomic_exchange_and_add. --- ports/sysdeps/mips/bits/atomic.h | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) (limited to 'ports/sysdeps') diff --git a/ports/sysdeps/mips/bits/atomic.h b/ports/sysdeps/mips/bits/atomic.h index b0942737dd..749e166908 100644 --- a/ports/sysdeps/mips/bits/atomic.h +++ b/ports/sysdeps/mips/bits/atomic.h @@ -193,11 +193,13 @@ typedef uintmax_t uatomic_max_t; __atomic_fetch_add (mem, value, model) # endif -/* ??? Barrier semantics for atomic_exchange_and_add appear to be - undefined. Use full barrier for now, as that's safe. */ -# define atomic_exchange_and_add(mem, value) \ +# define atomic_exchange_and_add_acq(mem, value) \ __atomic_val_bysize (__arch_exchange_and_add, int, mem, value, \ - __ATOMIC_ACQ_REL) + __ATOMIC_ACQUIRE) + +# define atomic_exchange_and_add_rel(mem, value) \ + __atomic_val_bysize (__arch_exchange_and_add, int, mem, value, \ + __ATOMIC_RELEASE) #else /* !__GNUC_PREREQ (4, 8) */ /* This implementation using inline assembly will be removed once glibc requires GCC 4.8 or later to build. */ @@ -434,11 +436,13 @@ typedef uintmax_t uatomic_max_t; __prev; }) # endif -/* ??? Barrier semantics for atomic_exchange_and_add appear to be - undefined. Use full barrier for now, as that's safe. */ -# define atomic_exchange_and_add(mem, value) \ - __atomic_val_bysize (__arch_exchange_and_add, int, mem, value, \ - MIPS_SYNC_STR, MIPS_SYNC_STR) +# define atomic_exchange_and_add_acq(mem, value) \ + __atomic_val_bysize (__arch_exchange_and_add, int, mem, value, \ + "", MIPS_SYNC_STR) + +# define atomic_exchange_and_add_rel(mem, value) \ + __atomic_val_bysize (__arch_exchange_and_add, int, mem, value, \ + MIPS_SYNC_STR, "") #endif /* __GNUC_PREREQ (4, 8) */ /* TODO: More atomic operations could be implemented efficiently; only the -- cgit 1.4.1