Added jumptable optimization (aka Proj(Cond(mode_int)) )

[r3624]

diff --git a/ir/ir/iropt.c b/ir/ir/iropt.c
index f40081a..3dab4dd 100644 (file)
--- a/ir/ir/iropt.c
+++ b/ir/ir/iropt.c
@@ -1300,6 +1300,29 @@ static ir_node *transform_node_Proj(ir_node *proj)
       set_Tuple_pred(n, pn_DivMod_res_mod, proj_mod);
     }
     break;
       set_Tuple_pred(n, pn_DivMod_res_mod, proj_mod);
     }
     break;

+
+  case iro_Cond:
+    if (get_opt_unreachable_code()) {
+      b = get_Cond_selector(n);
+      tb = computed_value(b);
+
+      if (tb != tarval_bad && mode_is_int(get_tarval_mode(tb))) {
+       /* we have a constant switch */
+       long num = get_Proj_proj(proj);
+
+       if (num != get_Cond_defaultProj(n)) { /* we cannot optimize default Proj's yet */
+         if (get_tarval_long(tb) == num) {
+           /* Do NOT create a jump here, or we will have 2 control flow ops
+            * in a block. This case is optimized away in optimize_cf(). */
+           return proj;
+         }
+         else
+           return new_Bad();
+       }
+      }
+    }
+    return proj;
+

   default:
     /* do nothing */
     return proj;
   default:
     /* do nothing */
     return proj;