ugtp:
UENT: If 68000 or Vax, don't allocate RsavAt
UABS: if Is68000 and real number, then let emitunaryop handle it
UADD/USUB/UINC/UDEC: You can get rid of Is68000, since I handle it in
	Emitbinaryop
UINN USGS Handled inefficiently for 68000, but left so. Should change later
UMUS: header comment: last word must be ANDed -instead of- ORed
UCVT2: restack At1 because moveit might call a subroutine,
	which needs the stack so it can save registers
	Should be a temporary hack
ULDP and other places: Inefficient code for machines with autoincrement!
