@Override
	public CodeBlock getCodeBlockAt(Address addr, TaskMonitor monitor) throws CancelledException {

		// First check out the Block cache
		CodeBlock block = foundModelP.getBlockAt(addr);
		if (block != null) {
			return block;
		}

		// get block containing addr, but return it only if it's entry point is addr
		block = getFirstCodeBlockContaining(addr, monitor);
		if (block != null) {
			if (block.getFirstStartAddress().equals(addr)) {
				return block;
			}
		}
		return null;
	}
@see ghidra.program.model.block.CodeBlockModel#getCodeBlockAt(ghidra.program.model.address.Address, ghidra.util.task.TaskMonitor)
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/model/block/PartitionCodeSubModel.java