predicates.md (ext_register_operand): Check that SUBREG_REG is really a register before looking for REGNO.

	* config/i386/predicates.md (ext_register_operand): Check that
	SUBREG_REG is really a register before looking for REGNO.
	(reg_not_xmm0_operand): Handle SUBREGs correctly.
	(nonimm_not_xmm0_operand): Call reg_not_xmm0_operand.

From-SVN: r164071