protected String print(Varnode rvnode) {
		if (rvnode == null) {
			return "<null>";
		}
		if (rvnode.isRegister()) {
			Register reg = this.trans.getRegister(rvnode);
			return (reg == null ? "<bad reg " + rvnode.getOffset() + ">" : reg.getName());
		}
		return rvnode.toString();
	}
Get the value (value, space, size) of a register at the end of the last execution
flow taken for the instruction at toAddr.

Note: This can only be called if trackStartEndState flag is true.

@param reg register to retrieve the end value
@param fromAddr flow from address (not used currently, future use to retrieve multiple flows)
@param toAddr address of instruction to retrieve the register flow state
@param signed is the value signed or unsigned, will sext the top bit based on value size

@return instruction end state value for register, or null if no known state

@throws UnsupportedOperationException trackStartEndState == false at construction
Ghidra/Features/Base/src/main/java/ghidra/program/util/VarnodeContext.java