8146629: Make phase->is_IterGVN() accessible from Node::Identity and Node::Value
Summary: Change arguments of Node::Identity() and Node::Value() from PhaseTransform* to PhaseGVN*.
Reviewed-by: kvn, roland

8004073: Implement C2 Ideal node specific dump() method
Summary: add Node::dump_rel() to dump a node and its related nodes (the notion of "related" depends on the node at hand); add Node::dump_comp() to dump a node in compact representation; add Node::dump_rel_comp() to dump a node and its related nodes in compact representation; add the required machinery; extend some C2 IR nodes with compact and related dumping
Reviewed-by: kvn, roland

8054033: Remove unused references to Compile*
Summary: Removed unused references to Compile* missed by JDK-8034812.
Reviewed-by: kvn, roland

8001532: C2 node files refactoring
Summary: Split C2 node files into cast, convert, countbits, intrinsic, move, narrowptr and opaquenode classes
Reviewed-by: kvn, morris