byte[] getForwardModMapData() {
		
		// Allocate map based upon number of buffers corresponding to latest version changes
		int bitMapSize = (originalBufCount + 7) / 8;
		byte[] data = new byte[bitMapSize];
		Arrays.fill(data, (byte)0);
		
		// Mark excess bits corresponding to maxBufCount and beyond as changed
		int excess = originalBufCount % 8;
		if (excess != 0) {
			data[bitMapSize-1] |= (byte)(0xff << excess);
		}
		for (int index : bufferMap.getKeys()) {
			if (index < originalBufCount) {
				setMapDataBit(data, index);
			}
		}
		return data;
	}
Returns a bit map corresponding to all buffers modified since
the original version (e.g., oldest).  This identifies all buffers contained within the original
version (e.g., oldest) which have been modified during any revision up until the original version.
NOTE: The bit mask may identify buffers which have been removed in the current version.
Ghidra/Framework/DB/src/main/java/db/buffers/VersionFileHandler.java