Equivalence <=> structural equality.
See Node.opIndex.
Semantic hash.
Provides an iterator over this node's in-edges.
Provides an iterator over this node's out-edges.
Frees all resources allocated by this node and sets it to an uninitialized state.
Initializes a extension node.
Post-move adjusts in-edge slots' owner pointer.
Yields a wider version of its input, with added bits equal to the input's sign bit.