8225475: Node budget asserts on x86_32/64

Make the (ad-hoc) loop cloning size estimate more pessimistic.

Backport-of: ca29203

Author: TheRealMDoerr

src/hotspot/share/opto/loopnode.cpp

@@ -2511,9 +2511,11 @@ uint IdealLoopTree::est_loop_clone_sz(uint factor) const {
       }
     }
   }
-  // Add data (x1.5) and control (x1.0) count to estimate iff both are > 0.
+  // Add data and control count (x2.0) to estimate iff both are > 0. This is
+  // a rather pessimistic estimate for the most part, in particular for some
+  // complex loops, but still not enough to capture all loops.
   if (ctrl_edge_out_cnt > 0 && data_edge_out_cnt > 0) {
-    estimate += ctrl_edge_out_cnt + data_edge_out_cnt + data_edge_out_cnt / 2;
+    estimate += 2 * (ctrl_edge_out_cnt + data_edge_out_cnt);
   }
 
   return estimate;