gas/

gas/
	* config/tc-mips.c (match_expression):  Report uses of registers here.
	Add a "must be an immediate expression" error.  Handle elided offsets
	here rather than...
	(match_int_operand): ...here.

gas/testsuite/
	* gas/mips/octeon-ill.l: Adjust expected output.
	* gas/mips/lui-1.l, gas/mips/lui-1.s: Add more cases.