THE ENTRIES TO THIS SUBROUTINE PROVIDE 'FRONT ENDS' TO
SUBROUTINE PLACE, TAILORED TO SPECIFIC PLACE TYPES. THEY
PROVIDE COMPATIBILITY WITH PREVIOUSLY SUPPORTED CALLING
SEQUENCES.
Nodes of different colours represent the following:
Solid arrows point from a procedure to one which it calls. Dashed
arrows point from an interface to procedures which implement that interface.
This could include the module procedures in a generic interface or the
implementation in a submodule of an interface in a parent module.