exceptionSetMap.put(basicBlock, cachedExceptionSet);
thrownExceptionSetMap.put(basicBlock, cachedExceptionSet);
	private CachedExceptionSet getCachedExceptionSet(BasicBlock basicBlock) {		CachedExceptionSet cachedExceptionSet = exceptionSetMap.get(basicBlock);		if (cachedExceptionSet == null) {			// When creating the cached exception type set for the first time:			// - the block result is set to TOP, so it won't match			//   any block result that has actually been computed			//   using the analysis transfer function			// - the exception set is created as empty (which makes it			//   return TOP as its common superclass)			TypeFrame top = createFact();			makeFactTop(top);			cachedExceptionSet = new CachedExceptionSet(top, new ExceptionSet());			exceptionSetMap.put(basicBlock, cachedExceptionSet);		}		return cachedExceptionSet;	}