private static void tagFunctionNames(FunctionManager funcMgr,Listing listing,
				TreeMap<String, MyFunction> mymap, boolean isSrc) {
			FunctionIterator functions = funcMgr.getFunctions(true);
			while (functions.hasNext()) {
				Function next = functions.next();
				if (next.isThunk()) continue;
				CodeUnit cu = listing.getCodeUnitAt(next.getEntryPoint());
				boolean hasbody = false;
				if ((cu != null) && (cu instanceof Instruction))
					hasbody = true;
				String funcName = getName(next);
				MyFunction myRec = mymap.get(funcName);
				if (myRec == null) {
					myRec = new MyFunction(funcName);
					mymap.put(myRec.name, myRec);
				}
				if (isSrc) {
					myRec.srcexists = true;
					myRec.srcbody = hasbody;
				}
				else {
					myRec.destexists = true;
					myRec.destbody = hasbody;
				}
			}
			// Make sure external functions have an entry
			functions = funcMgr.getExternalFunctions();
			while(functions.hasNext()) {
				Function next = functions.next();
				String funcName = getName(next);
				MyFunction myRec = mymap.get(funcName);
				if (myRec == null) {
					myRec = new MyFunction(funcName);
					mymap.put(myRec.name, myRec);
				}
				if (isSrc) {
					myRec.srcexists = true;
					myRec.srcbody = false;
				}
				else {
					myRec.destexists = true;
					myRec.destbody = false;
				}
			}
		}
For every function in a manager, make sure a record exists in -mymap-
@param funcMgr is the manager to iterate over
@param mymap is the map to add records to
@param isSrc is true if the srcexists field should be set to true, otherwise destexists is set
Ghidra/Features/VersionTracking/developer_scripts/EvaluateVTMatch.java