@Override
	public T getVar(AddressSpace space, long offset, int size, boolean quantize,
			Reason reason) {
		checkRange(space, offset, size);
		if (space.isConstantSpace()) {
			return arithmetic.fromConst(offset, size);
		}
		if (space.isUniqueSpace()) {
			return getUnique(offset, size, reason);
		}
		S s = getForSpace(space, false);
		if (s == null) {
			return getFromNullSpace(size, reason);
		}
		offset = quantizeOffset(space, offset);
		return getFromSpace(s, offset, size, reason);
	}
In case spaces are generated lazily, and we're reading from a space that doesn't yet exist,
"read" a default value.

<p>
By default, the returned value is 0, which should be reasonable for all implementations.

@param size the number of bytes to read (the size of the value)
@param reason the reason for reading state
@return the default value
Ghidra/Framework/Emulation/src/main/java/ghidra/pcode/exec/AbstractLongOffsetPcodeExecutorStatePiece.java