VirtualBaseTableEntry getOrParseEntryByOrdinal(int ordinal) throws PdbException {
			VirtualBaseTableEntry entry = entryByOrdinal.get(ordinal);
			if (entry == null) {
				entry = parseVbtEntryFromMemory(memory, address, ordinal, entrySize);
				addEntry(ordinal, entry);
			}
			return entry;
		}
Returns the offset from the virtual base table entry
@param address Address of virtual base table
@param ordinal index into table
@param size size of a vbt entry offset value
@return the offset
@throws PdbException if no table exists for address or no entry exists for ordinal
Ghidra/Features/PDB/src/main/java/ghidra/app/util/pdb/pdbapplicator/PdbVbtManager.java