* config/tc-mips.c (INSERT_BITS, EXTRACT_BITS, INSERT_OPERAND)

	(EXTRACT_OPERAND, MIPS16_INSERT_OPERAND, MIPS16_EXTRACT_OPERAND): New.
	(insn_uses_reg, reg_needs_delay, append_insn, macro_build)
	(mips16_macro_build, macro_build_lui, mips16_macro, mips_ip)
	(mips16_ip): Use the new macros instead of explicit masks and shifts.