public static AssemblyPatternBlock fromLength(int length) {
		byte[] mask = new byte[length];
		byte[] vals = new byte[length];
		return new AssemblyPatternBlock(0, mask, vals);
	}
Allocate a fully-undefined pattern block of the given length

@param length the length in bytes
@return the block of all unknown bits
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/app/plugin/assembler/sleigh/sem/AssemblyPatternBlock.java