[PATCH] Adjust call stmt cost for tailcalls

[Richard Guenther]

Tailcalls have no argument setup cost and no return value cost.
This patch adjusts estminate_num_insns to reflect that.

Honza, does this look correct?

Bootstrapped and tested on x86_64-unknown-linux-gnu.

Thanks,
Richard.

2012-06-20  Richard Guenther  <rguent...@suse.de>

        * tree-inline.c (estimate_num_insns): Estimate call cost for
        tailcalls properly.

Index: gcc/tree-inline.c
===================================================================
--- gcc/tree-inline.c   (revision 188817)
+++ gcc/tree-inline.c   (working copy)
@@ -3611,12 +3611,15 @@ estimate_num_insns (gimple stmt, eni_wei
          }
 
        cost = node ? weights->call_cost : weights->indirect_call_cost;
-       if (gimple_call_lhs (stmt))
-         cost += estimate_move_cost (TREE_TYPE (gimple_call_lhs (stmt)));
-       for (i = 0; i < gimple_call_num_args (stmt); i++)
+       if (!gimple_call_tail_p (stmt))
          {
-           tree arg = gimple_call_arg (stmt, i);
-           cost += estimate_move_cost (TREE_TYPE (arg));
+           if (gimple_call_lhs (stmt))
+             cost += estimate_move_cost (TREE_TYPE (gimple_call_lhs (stmt)));
+           for (i = 0; i < gimple_call_num_args (stmt); i++)
+             {
+               tree arg = gimple_call_arg (stmt, i);
+               cost += estimate_move_cost (TREE_TYPE (arg));
+             }
          }
        break;
       }