@Override
	public MaskedLong getValue(EndInstructionValue iv, Map<String, Long> vals,
			AssemblyResolvedPatterns cur) throws NeedsBackfillException {
		Long instNext = vals.get(AbstractAssemblyTreeResolver.INST_NEXT);
		if (instNext == null) {
			throw new NeedsBackfillException(AbstractAssemblyTreeResolver.INST_NEXT);
		}
		return MaskedLong.fromLong(instNext);
	}
I suppose we could instead throw NeedsBackfillException(INST_NEXT) here, too, but this
serves as a sanity check on the SLEIGH spec. I can't think of a good reason to try to
solve INST_NEXT == const.
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/app/plugin/assembler/sleigh/expr/EndInstructionValueSolver.java