public boolean isFallThrough() {
		return index == code.size();
	}
Check if the index has advanced past the end of the p-code program

<p>
If the index has advanced beyond the program, it implies the program has finished executing.
In the case of instruction emulation, no branch was encountered. The machine should advance
to the fall-through instruction.

@see #isBranch()
@see #isFinished()
@return true if the program completed without branching
Ghidra/Framework/Emulation/src/main/java/ghidra/pcode/exec/PcodeFrame.java