The fix for ticket #2560 was somehow removed in the

great autogen update.  Therefore, put them back.

This commit was SVN r24053.

opal/config/opal_config_asm.m4

@@ -10,6 +10,7 @@ dnl                         University of Stuttgart.  All rights reserved.
 dnl Copyright (c) 2004-2005 The Regents of the University of California.
 dnl                         All rights reserved.
 dnl Copyright (c) 2008-2009 Cisco Systems, Inc.  All rights reserved.
+dnl Copyright (c) 2010      Oracle and/or its affiliates.  All rights reserved.
 dnl $COPYRIGHT$
 dnl 
 dnl Additional copyrights may follow
@@ -562,6 +563,13 @@ dnl For PowerPC, this would be:
 dnl
 dnl   "li %0,0" : "=&r"(ret)
 dnl
+dnl For testing ia32 assembly, the assembly instruction xaddl is
+dnl tested.  The xaddl instruction is used by some of the atomic
+dnl implementations so it makes sense to test for it.  In addition,
+dnl some compilers (i.e. earlier versions of Sun Studio 12) do not
+dnl necessarily handle xaddl properly, so that needs to be detected
+dnl during configure time.
+dnl
 dnl DEFINE OMPI_GCC_INLINE_ASSEMBLY to 0 or 1 depending on GCC
 dnl                support
 dnl
@@ -588,6 +596,7 @@ AC_DEFUN([OMPI_CHECK_INLINE_C_GCC],[
                         AC_RUN_IFELSE([AC_LANG_PROGRAM([
 AC_INCLUDES_DEFAULT],
 [[int ret = 1;
+int negone = -1;
 __asm__ __volatile__ ($assembly);
 return ret;]])],
                     [asm_result="yes"], [asm_result="no"], 
@@ -603,6 +612,7 @@ return ret;]])],
             AC_LINK_IFELSE([AC_LANG_PROGRAM([
 AC_INCLUDES_DEFAULT],
 [[int ret = 1;
+int negone = -1;
 __asm__ __volatile__ ($assembly);
 return ret;]])],
             [asm_result="yes"], [asm_result="no"])
@@ -642,6 +652,7 @@ AC_DEFUN([OMPI_CHECK_INLINE_CXX_GCC],[
             AC_RUN_IFELSE([AC_LANG_PROGRAM([
 AC_INCLUDES_DEFAULT],
 [[int ret = 1;
+int negone = -1;
 __asm__ __volatile__ ($assembly);
 return ret;]])],
                     [asm_result="yes"], [asm_result="no"], 
@@ -656,6 +667,7 @@ return ret;]])],
         AC_LINK_IFELSE([AC_LANG_PROGRAM([
 AC_INCLUDES_DEFAULT],
 [[int ret = 1;
+int negone = -1;
 __asm__ __volatile__ ($assembly);
 return ret;]])],
             [asm_result="yes"], [asm_result="no"])
@@ -873,7 +885,7 @@ AC_DEFUN([OPAL_CONFIG_ASM],[
                 ompi_cv_asm_arch="AMD64"
             fi
             OPAL_ASM_SUPPORT_64BIT=1
-            OMPI_GCC_INLINE_ASSIGN='"movl [$]0, %0" : "=&r"(ret)'
+            OMPI_GCC_INLINE_ASSIGN='"xaddl %1,%0" : "=m"(ret), "+r"(negone)'
             ;;
 
         ia64-*)

opal/include/opal/sys/ia32/atomic.h

@@ -9,7 +9,7 @@
  *                         University of Stuttgart.  All rights reserved.
  * Copyright (c) 2004-2005 The Regents of the University of California.
  *                         All rights reserved.
- * Copyright (c) 2007      Sun Microsystems, Inc.  All rights reserverd.
+ * Copyright (c) 2007-2010 Oracle and/or its affiliates.  All rights reserved.
  * $COPYRIGHT$
  * 
  * Additional copyrights may follow
@@ -164,11 +164,12 @@ static inline int opal_atomic_cmpset_64(volatile int64_t *addr,
  */
 static inline int32_t opal_atomic_add_32(volatile int32_t* v, int i)
 {
+    int ret = i;
    __asm__ __volatile__(
-                        SMPLOCK "addl %1,%0"
-                        :"=m" (*v)
-                        :"ir" (i), "m" (*v));
-   return (*v);  /* should be an atomic operation */
+                        SMPLOCK "xaddl %1,%0"
+                        :"=m" (*v), "+r" (ret)
+                        );
+   return (ret+i);
 }
 
 
@@ -181,11 +182,12 @@ static inline int32_t opal_atomic_add_32(volatile int32_t* v, int i)
  */
 static inline int32_t opal_atomic_sub_32(volatile int32_t* v, int i)
 {
+    int ret = -i;
    __asm__ __volatile__(
-                        SMPLOCK "subl %1,%0"
-                        :"=m" (*v)
-                        :"ir" (i), "m" (*v));
-   return (*v);  /* should be an atomic operation */
+                        SMPLOCK "xaddl %1,%0"
+                        :"=m" (*v), "+r" (ret)
+                        );
+   return (ret-i);
 }
 
 #endif /* OMPI_GCC_INLINE_ASSEMBLY */