public MaskedLong subtract(MaskedLong that) {
		if (!this.isFullyDefined() || !that.isFullyDefined()) {
			return doRippleCarry(this, that, true);
		}
		return fromMaskAndValue(-1, this.val - that.val);
	}
Compute the arithmetic difference: this masked long minus another

@param that the other masked long.
@return the result.
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/app/plugin/assembler/sleigh/expr/MaskedLong.java