Define atomic_compare_and_exchange_val_acq,
authordrepper <drepper>
Sat, 13 Jan 2007 01:52:31 +0000 (01:52 +0000)
committerdrepper <drepper>
Sat, 13 Jan 2007 01:52:31 +0000 (01:52 +0000)
atomic_compare_and_exchange_bool_acq, and atomic_exchange_and_add
using __sync_* built-ins for gcc >= 4.1.

sysdeps/i386/i486/bits/atomic.h

index a27734c..4577499 100644 (file)
@@ -1,4 +1,4 @@
-/* Copyright (C) 2002, 2003, 2004, 2006 Free Software Foundation, Inc.
+/* Copyright (C) 2002, 2003, 2004, 2006, 2007 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
 
@@ -56,26 +56,33 @@ typedef uintmax_t uatomic_max_t;
 #endif
 
 
-#define __arch_compare_and_exchange_val_8_acq(mem, newval, oldval) \
+#if __GNUC_PREREQ (4, 1)
+# define atomic_compare_and_exchange_val_acq(mem, newval, oldval) \
+  __sync_val_compare_and_swap (mem, oldval, newval)
+#  define atomic_compare_and_exchange_bool_acq(mem, newval, oldval) \
+  (! __sync_bool_compare_and_swap (mem, oldval, newval))
+#else
+# define __arch_compare_and_exchange_val_8_acq(mem, newval, oldval) \
   ({ __typeof (*mem) ret;                                                    \
      __asm __volatile (LOCK_PREFIX "cmpxchgb %b2, %1"                        \
                       : "=a" (ret), "=m" (*mem)                              \
                       : "q" (newval), "m" (*mem), "0" (oldval));             \
      ret; })
 
-#define __arch_compare_and_exchange_val_16_acq(mem, newval, oldval) \
+# define __arch_compare_and_exchange_val_16_acq(mem, newval, oldval) \
   ({ __typeof (*mem) ret;                                                    \
      __asm __volatile (LOCK_PREFIX "cmpxchgw %w2, %1"                        \
                       : "=a" (ret), "=m" (*mem)                              \
                       : "r" (newval), "m" (*mem), "0" (oldval));             \
      ret; })
 
-#define __arch_compare_and_exchange_val_32_acq(mem, newval, oldval) \
+# define __arch_compare_and_exchange_val_32_acq(mem, newval, oldval) \
   ({ __typeof (*mem) ret;                                                    \
      __asm __volatile (LOCK_PREFIX "cmpxchgl %2, %1"                         \
                       : "=a" (ret), "=m" (*mem)                              \
                       : "r" (newval), "m" (*mem), "0" (oldval));             \
      ret; })
+#endif
 
 
 #define __arch_c_compare_and_exchange_val_8_acq(mem, newval, oldval) \
@@ -240,8 +247,13 @@ typedef uintmax_t uatomic_max_t;
        }                                                                     \
      __result; })
 
-#define atomic_exchange_and_add(mem, value) \
+#if __GNUC_PREREQ (4, 1)
+# define atomic_exchange_and_add(mem, value) \
+  __sync_fetch_and_add (mem, value)
+#else
+# define atomic_exchange_and_add(mem, value) \
   __arch_exchange_and_add_body (LOCK_PREFIX, __arch, mem, value)
+#endif
 
 #define __arch_exchange_and_add_cprefix \
   "cmpl $0, %%gs:%P4\n\tje 0f\n\tlock\n0:\t"