public static long zeroExtend(long val, int bit) {
		long mask = 0;
		mask = (~mask) << bit;
		mask <<= 1;
		val &= (~mask);
		return val;
	}
Clear all bits in -val- above -bit-
@param val   value to zero extend
@param bit   bit above which to zero extend
@return the extended value
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/app/plugin/processors/sleigh/expression/TokenField.java