Update.

2003-03-20  Ulrich Drepper  <drepper@redhat.com>

	* include/atomic.h: Define atomic_exchange and
	atomic_decrement_if_positive if not already defined.  Add some
	__builtin_expect.
	* sysdeps/i386/i486/bits/atomic.h: Define atomic_exchange.
	* sysdeps/x86_64/bits/atomic.h: Likewise.
	* sysdeps/ia64/bits/atomic.h: Pretty printing.  Define atomic_exchange.
	* sysdeps/powerpc/bits/atomic.h: Pretty printing.  Define
	atomic_exchange, atomic_exchange_and_add, and
	atomic_decrement_if_positive

diff --git a/ChangeLog b/ChangeLog
index 2d0522d..0418130 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,15 @@
+2003-03-20  Ulrich Drepper  <drepper@redhat.com>
+
+       * include/atomic.h: Define atomic_exchange and
+       atomic_decrement_if_positive if not already defined.  Add some
+       __builtin_expect.
+       * sysdeps/i386/i486/bits/atomic.h: Define atomic_exchange.
+       * sysdeps/x86_64/bits/atomic.h: Likewise.
+       * sysdeps/ia64/bits/atomic.h: Pretty printing.  Define atomic_exchange.
+       * sysdeps/powerpc/bits/atomic.h: Pretty printing.  Define
+       atomic_exchange, atomic_exchange_and_add, and
+       atomic_decrement_if_positive
+
 2003-03-20  Alexandre Oliva  <aoliva@redhat.com>
 
        * sysdeps/unix/sysv/linux/mips/mips64/n64/ioctl.S: Sign-extend

diff --git a/sysdeps/i386/i486/bits/atomic.h b/sysdeps/i386/i486/bits/atomic.h
index 87739c6..e22e560 100644 (file)
--- a/sysdeps/i386/i486/bits/atomic.h
+++ b/sysdeps/i386/i486/bits/atomic.h
@@ -119,6 +119,29 @@ typedef uintmax_t uatomic_max_t;
 #endif
 
 
+/* Note that we need no lock prefix.  */
+#define atomic_exchange(mem, newvalue) \
+  ({ __typeof (*mem) result;                                                 \
+     if (sizeof (*mem) == 1)                                                 \
+       __asm __volatile ("xchgb %b0, %1"                                     \
+                        : "=r" (result), "=m" (*mem)                         \
+                        : "0" (newvalue), "1" (*mem));                       \
+     else if (sizeof (*mem) == 2)                                            \
+       __asm __volatile ("xchgw %w0, %1"                                     \
+                        : "=r" (result), "=m" (*mem)                         \
+                        : "0" (newvalue), "1" (*mem));                       \
+     else if (sizeof (*mem) == 4)                                            \
+       __asm __volatile ("xchgl %0, %1"                                              \
+                        : "=r" (result), "=m" (*mem)                         \
+                        : "0" (newvalue), "1" (*mem));                       \
+     else                                                                    \
+       {                                                                     \
+        result = 0;                                                          \
+        abort ();                                                            \
+       }                                                                     \
+     result; })
+
+
 #define atomic_exchange_and_add(mem, value) \
   ({ __typeof (*mem) result;                                                 \
      __typeof (value) addval = (value);                                              \

diff --git a/sysdeps/ia64/bits/atomic.h b/sysdeps/ia64/bits/atomic.h
index fab2307..7c6ebf1 100644 (file)
--- a/sysdeps/ia64/bits/atomic.h
+++ b/sysdeps/ia64/bits/atomic.h
@@ -55,7 +55,7 @@ typedef uintmax_t uatomic_max_t;
   (!__sync_bool_compare_and_swap_si ((int *) (mem), (int) (long) (oldval), \
                                     (int) (long) (newval)))
 
-# define __arch_compare_and_exchange_64_acq(mem, newval, oldval) \
+#define __arch_compare_and_exchange_64_acq(mem, newval, oldval) \
   (!__sync_bool_compare_and_swap_di ((long *) (mem), (long) (oldval), \
                                     (long) (newval)))
 
@@ -63,11 +63,15 @@ typedef uintmax_t uatomic_max_t;
   __sync_val_compare_and_swap_si ((int *) (mem), (int) (long) (oldval), \
                                  (int) (long) (newval))
 
-# define __arch_compare_and_exchange_64_val_acq(mem, newval, oldval) \
+#define __arch_compare_and_exchange_64_val_acq(mem, newval, oldval) \
   __sync_val_compare_and_swap_di ((long *) (mem), (long) (oldval), \
                                  (long) (newval))
 
-# define atomic_exchange_and_add(mem, value) \
+/* Atomically store newval and return the old value.  */
+#define atomic_exchange(mem, value) \
+  __sync_lock_test_and_set_si (mem, value)
+
+#define atomic_exchange_and_add(mem, value) \
   ({                                                                         \
     __typeof (*mem) __oldval, __val;                                         \
     __typeof (mem) __memp = (mem);                                           \

diff --git a/sysdeps/powerpc/bits/atomic.h b/sysdeps/powerpc/bits/atomic.h
index af61563..13001cb 100644 (file)
--- a/sysdeps/powerpc/bits/atomic.h
+++ b/sysdeps/powerpc/bits/atomic.h
@@ -53,11 +53,11 @@ typedef uintmax_t uatomic_max_t;
   (abort (), 0)
 
 #ifdef UP
-#define __ARCH_ACQ_INSTR       ""
-#define __ARCH_REL_INSTR       ""
+# define __ARCH_ACQ_INSTR      ""
+# define __ARCH_REL_INSTR      ""
 #else
-#define __ARCH_ACQ_INSTR       "isync"
-#define __ARCH_REL_INSTR       "sync"
+# define __ARCH_ACQ_INSTR      "isync"
+# define __ARCH_REL_INSTR      "sync"
 #endif
 
 /*
@@ -86,7 +86,7 @@ typedef uintmax_t uatomic_max_t;
 })
 
 #ifdef __powerpc64__
-#define __arch_compare_and_exchange_64_acq(mem, newval, oldval)        \
+# define __arch_compare_and_exchange_64_acq(mem, newval, oldval)\
 ({                                                             \
   unsigned long        __tmp;                                          \
   __asm __volatile (__ARCH_REL_INSTR "\n"                      \
@@ -103,14 +103,64 @@ typedef uintmax_t uatomic_max_t;
 })
 
 #else /* powerpc32 */
-#define __arch_compare_and_exchange_64_acq(mem, newval, oldval) \
+# define __arch_compare_and_exchange_64_acq(mem, newval, oldval) \
   (abort (), 0)
 #endif
 
+
+#define atomic_exchange(mem, value) \
+  ({ if (sizeof (*mem) != 4)                                                 \
+       abort ();                                                             \
+     int __val, __tmp;                                                       \
+      __asm __volatile (__ARCH_REL_INSTR "\n"                                \
+                       "1:     lwarx   %0,0,%2\n"                            \
+                       "       stwcx.  %3,0,%2\n"                            \
+                       "       bne-    1b"                                   \
+                       : "=&r" (__val), "=m" (*mem)                          \
+                       : "r" (mem), "r" (value), "1" (*mem)                  \
+                       : "cr0", "memory");                                   \
+      __val; })
+
+
+#define atomic_exchange_and_add(mem, value) \
+  ({ if (sizeof (*mem) != 4)                                                 \
+       abort ();                                                             \
+     int __val, __tmp;                                                       \
+     __asm __volatile ("1:     lwarx   %0,0,%3\n"                            \
+                      "        addi    %1,%0,%4\n"                           \
+                      "        stwcx.  %1,0,%3\n"                            \
+                      "        bne-    1b"                                   \
+                      : "=&b" (__val), "=&r" (__tmp), "=m" (*mem)            \
+                      : "r" (mem), "I" (value), "2" (*mem)                   \
+                      : "cr0");                                              \
+     __val;                                                                  \
+  })
+
+
+/* Decrement *MEM if it is > 0, and return the old value.  */
+#define atomic_decrement_if_positive(mem) \
+  ({ if (sizeof (*mem) != 4)                                                 \
+       abort ();                                                             \
+     int __val, __tmp;                                                       \
+     __asm __volatile ("1:     lwarx   %0,0,%3\n"                            \
+                      "        cmpwi   0,%0,0\n"                             \
+                      "        addi    %1,%0,-1\n"                           \
+                      "        ble     2f\n"                                 \
+                      "        stwcx.  %1,0,%3\n"                            \
+                      "        bne-    1b\n"                                 \
+                      "2:      " __ARCH_ACQ_INSTR                            \
+                      : "=&b" (__val), "=&r" (__tmp), "=m" (*mem)            \
+                      : "r" (mem), "2" (*mem)                                \
+                      : "cr0");                                              \
+     __val;                                                                  \
+  })
+
+
+
 #define atomic_full_barrier()  __asm ("sync" ::: "memory")
 #ifdef __powerpc64__
-#define atomic_read_barrier()  __asm ("lwsync" ::: "memory")
+# define atomic_read_barrier() __asm ("lwsync" ::: "memory")
 #else
-#define atomic_read_barrier()  __asm ("sync" ::: "memory")
+# define atomic_read_barrier() __asm ("sync" ::: "memory")
 #endif
 #define atomic_write_barrier() __asm ("eieio" ::: "memory")

diff --git a/sysdeps/x86_64/bits/atomic.h b/sysdeps/x86_64/bits/atomic.h
index f72f16c..22d3ab0 100644 (file)
--- a/sysdeps/x86_64/bits/atomic.h
+++ b/sysdeps/x86_64/bits/atomic.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2002 Free Software Foundation, Inc.
+/* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
 
@@ -84,6 +84,28 @@ typedef uintmax_t uatomic_max_t;
      ret; })
 
 
+/* Note that we need no lock prefix.  */
+#define atomic_exchange(mem, newvalue) \
+  ({ __typeof (*mem) result;                                                 \
+     if (sizeof (*mem) == 1)                                                 \
+       __asm __volatile ("xchgb %b0, %1"                                     \
+                        : "=r" (result), "=m" (*mem)                         \
+                        : "0" (newvalue), "1" (*mem));                       \
+     else if (sizeof (*mem) == 2)                                            \
+       __asm __volatile ("xchgw %w0, %1"                                     \
+                        : "=r" (result), "=m" (*mem)                         \
+                        : "0" (newvalue), "1" (*mem));                       \
+     else if (sizeof (*mem) == 4)                                            \
+       __asm __volatile ("xchgl %0, %1"                                              \
+                        : "=r" (result), "=m" (*mem)                         \
+                        : "0" (newvalue), "1" (*mem));                       \
+     else                                                                    \
+       __asm __volatile ("xchgq %q0, %1"                                     \
+                        : "=r" (result), "=m" (*mem)                         \
+                        : "0" (newvalue), "1" (*mem));                       \
+     result; })
+
+
 #define atomic_exchange_and_add(mem, value) \
   ({ __typeof (*mem) result;                                                 \
      if (sizeof (*mem) == 1)                                                 \