--- old/src/share/vm/opto/phaseX.cpp 2012-11-27 18:45:19.139266259 -0800 +++ new/src/share/vm/opto/phaseX.cpp 2012-11-27 18:45:18.751418993 -0800 @@ -383,6 +383,8 @@ // Identify nodes that are reachable from below, useful. C->identify_useful_nodes(_useful); + // Update dead node list + C->update_dead_node_list(_useful); // Remove all useless nodes from PhaseValues' recorded types // Must be done before disconnecting nodes to preserve hash-table-invariant @@ -1190,7 +1192,7 @@ } } } - + C->record_dead_node(dead->_idx); if (dead->is_macro()) { C->remove_macro_node(dead); } @@ -1199,6 +1201,11 @@ continue; } } + // Constant node that has no out-edges and has only one in-edge from + // root is usually dead. However, sometimes reshaping walk makes + // it reachable by adding use edges. So, we will NOT count Con nodes + // as dead to be conservative about the dead node count at any + // given time. } // Aggressively kill globally dead uses