builtins.c (expand_builtin_expect_jump): Disable if the expression can't be re-evaluated.

        * builtins.c (expand_builtin_expect_jump): Disable if the
        expression can't be re-evaluated.

From-SVN: r43543

gcc/ChangeLog

+2001-06-24  Richard Henderson  <rth@redhat.com>
+
+	* builtins.c (expand_builtin_expect_jump): Disable if the
+	expression can't be re-evaluated.
+
 2001-06-24  Nick Clifton  <nickc@cambridge.redhat.com>
 
 	* config/arm/arm.c (arm_compute_save_reg_mask): For FIQ interrupt

gcc/builtins.c

@@ -3304,6 +3304,22 @@ expand_builtin_expect_jump (exp, if_false_label, if_true_label)
       int j;
       int num_jumps = 0;
 
+      /* If we fail to locate an appropriate conditional jump, we'll
+	 fall back to normal evaluation.  Ensure that the expression
+	 can be re-evaluated.  */
+      switch (unsafe_for_reeval (arg0))
+	{
+	case 0: /* Safe.  */
+	  break;
+
+	case 1: /* Mildly unsafe.  */
+	  arg0 = unsave_expr (arg0);
+	  break;
+
+	case 2: /* Wildly unsafe.  */
+	  return NULL_RTX;
+	}
+
       /* Expand the jump insns.  */
       start_sequence ();
       do_jump (arg0, if_false_label, if_true_label);