public static AssemblyPatternBlock fromRegisterValue(RegisterValue rv) {
		byte[] mb = rv.toBytes();
		byte[] mask = new byte[mb.length / 2];
		byte[] vals = new byte[mb.length / 2];
		System.arraycopy(mb, 0, mask, 0, mb.length / 2);
		System.arraycopy(mb, mb.length / 2, vals, 0, mb.length / 2);
		return new AssemblyPatternBlock(0, mask, vals);
	}
Convert a register value into a pattern block

<p>
This is used primarily to compute default context register values, and pass them into an
assembler.

@param rv the register value
@return the pattern block
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/app/plugin/assembler/sleigh/sem/AssemblyPatternBlock.java