Emulating legacy hardware using IEEE 754 compliant hardware is disclosed herein. In some aspects, the emulation includes locating an instruction that includes NaN (not a number) as at least one of an operand or a resultant. The emulation adjusts the resultant of the instruction, via additional code, to produce a final resultant of non-compliant (legacy) hardware. Legacy software, which was written in anticipation of processing by legacy hardware, may then be processed using compliant hardware.