// IfsOverlays.decl -- declaration for IFS Overlays package
// Copyright Xerox Corporation 1980

// Last modified March 1, 1980  3:07 PM by Taft

// Derived from OVERLAYS.D, by P. Deutsch
// last edited May 17, 1977  4:15 PM
//


structure OD:	// overlay descriptor
	[
	JSR word	// STA3JSRI OverlaySave
	da word		// disk address
	core word	// core page (for lock)
	onstack bit 1	// 1 if referenced from stack
	firstPn bit 15	// first page # in file
	]
manifest lOD = size OD/16

structure OEP:	// overlay special entry point
	[
	JSRJMP word	// JMP @.+1 if present in bank 0,
			// XJMP b if present in bank b,
			// STA3JSRI OverlaySave if not present.
	ODorEP word	// overlay descriptor address or code entry point
	]
manifest lOEP = size OEP/16