void initializeBlock(byte initialValue) throws IOException {
		lastSubBlock = null;
		for (SubMemoryBlock subBlock : subBlocks) {
			subBlock.delete();
		}
		subBlocks.clear();

		int numFullBlocks = (int) (length / Memory.GBYTE);
		int lastSubBlockSize = (int) (length % Memory.GBYTE);
		long blockOffset = 0;
		for (int i = 0; i < numFullBlocks; i++) {
			createBufferSubBlock(initialValue, blockOffset, (int) Memory.GBYTE);
			blockOffset += Memory.GBYTE;
		}
		if (lastSubBlockSize > 0) {
			createBufferSubBlock(initialValue, blockOffset, lastSubBlockSize);
		}
	}
Get collection of blocks which map onto this block.

@return collection of blocks which map onto this block or null if none identified
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/mem/MemoryBlockDB.java