optabs.c (expand_sync_operation): Use plus insn if minus CONST_INT_P(val).

	* optabs.c (expand_sync_operation):  Use plus insn if minus
	CONST_INT_P(val).
	(expand_sync_fetch_operation):  Ditto.

From-SVN: r128322

gcc/ChangeLog

+2007-09-09  David Daney  <ddaney@avtrex.com>
+
+	* optabs.c (expand_sync_operation):  Use plus insn if minus
+	CONST_INT_P(val).
+	(expand_sync_fetch_operation):  Ditto.
+
 2007-09-09  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* i386.md (*floatsisf2_mixed_vector): Use cvtdq2ps instead

gcc/optabs.c

@@ -7242,7 +7242,7 @@ expand_sync_operation (rtx mem, rtx val, enum rtx_code code)
 
     case MINUS:
       icode = sync_sub_optab[mode];
-      if (icode == CODE_FOR_nothing)
+      if (icode == CODE_FOR_nothing || CONST_INT_P (val))
 	{
 	  icode = sync_add_optab[mode];
 	  if (icode != CODE_FOR_nothing)
@@ -7342,7 +7342,8 @@ expand_sync_fetch_operation (rtx mem, rtx val, enum rtx_code code,
     case MINUS:
       old_code = sync_old_sub_optab[mode];
       new_code = sync_new_sub_optab[mode];
-      if (old_code == CODE_FOR_nothing && new_code == CODE_FOR_nothing)
+      if ((old_code == CODE_FOR_nothing && new_code == CODE_FOR_nothing)
+          || CONST_INT_P (val))
 	{
 	  old_code = sync_old_add_optab[mode];
 	  new_code = sync_new_add_optab[mode];