@Override
	public BigInteger getValue(Register register, boolean signed) {
		if (signed) {
			throw new UnsupportedOperationException();
		}
		if (!register.isProcessorContext()) {
			return null;
		}
		BigInteger res = curctx.toBigInteger(register.getMinimumByteSize());
		if (register.isBaseRegister()) {
			return res;
		}
		throw new UnsupportedOperationException();
	}
Compute the default value of the context register at the given address

@param addr the addres
@return the value as a pattern block for assembly
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/app/plugin/assembler/sleigh/sem/AssemblyDefaultContext.java