StgWord result;
result = w;
__asm__ __volatile__ (
- "xchgl %1,%0"
+ "xchg %1,%0"
:"+r" (result), "+m" (*p)
: /* no input-only operands */
);
INLINE_HEADER StgInfoTable *
lockClosure(StgClosure *p)
{
+#if i386_HOST_ARCH || x86_64_HOST_ARCH
StgWord info;
-#if 0
do {
info = xchg((P_)&p->header.info, (W_)&stg_WHITEHOLE_info);
if (info != (W_)&stg_WHITEHOLE_info) return (StgInfoTable *)info;
yieldThread();
} while (1);
#else
- info = p->header.info;
+ ACQUIRE_SM_LOCK
+#endif
+}
+
+INLINE_HEADER void
+unlockClosure(StgClosure *p, StgInfoTable *info)
+{
+#if i386_HOST_ARCH || x86_64_HOST_ARCH
+ // This is safe enough, because lockClosure() does the memory barrier:
+ p->header.info = info;
+#else
+ RELEASE_SM_LOCK;
#endif
}