added code to avoid unordered fp compares

diff --git a/ir/be/ia32/ia32_finish.c b/ir/be/ia32/ia32_finish.c
index 0a39293..c953b1e 100644 (file)
--- a/ir/be/ia32/ia32_finish.c
+++ b/ir/be/ia32/ia32_finish.c
@@ -299,10 +299,36 @@ insert_copy:
                        }
                }
 
-               /* If we have a CondJmp/CmpSet/xCmpSet with immediate, we need to    */
-               /* check if it's the right operand, otherwise we have */
-               /* to change it, as CMP doesn't support immediate as  */
-               /* left operands.                                     */
+               /* check xCmp: try to avoid unordered cmp */
+               if ((is_ia32_xCmp(irn) || is_ia32_xCmpCMov(irn) || is_ia32_xCmpSet(irn)) &&
+                       op_tp == ia32_Normal    &&
+                       ! is_ia32_ImmConst(irn) && ! is_ia32_ImmSymConst(irn))
+               {
+                       long pnc = get_ia32_pncode(irn);
+
+                       if (pnc & pn_Cmp_Uo) {
+                               ir_node *tmp;
+                               int idx1 = 2, idx2 = 3;
+
+                               if (is_ia32_xCmpCMov(irn)) {
+                                       idx1 = 0;
+                                       idx2 = 1;
+                               }
+
+                               tmp = get_irn_n(irn, idx1);
+                               set_irn_n(irn, idx1, get_irn_n(irn, idx2));
+                               set_irn_n(irn, idx2, tmp);
+
+                               set_ia32_pncode(irn, get_negated_pnc(pnc, mode_D));
+                       }
+               }
+
+               /*
+                       If we have a CondJmp/CmpSet/xCmpSet with immediate,
+                       we need to check if it's the right operand, otherwise
+                       we have to change it, as CMP doesn't support immediate
+                       as left operands.
+               */
                if ((is_ia32_CondJmp(irn) || is_ia32_CmpSet(irn) || is_ia32_xCmpSet(irn)) &&
                        (is_ia32_ImmConst(irn) || is_ia32_ImmSymConst(irn))                   &&
                        op_tp == ia32_AddrModeS)