protected void parse1(int currentPass, ParserFactory factory, Collection<InputDescriptor> sources, boolean shuffleSources) throws InterruptedException {
		if (FILE_GRANULARITY) {
			System.gc();
		}

        parseSources(currentPass, factory, sources, shuffleSources);
    }
This method is separate from {@link #parse2} so the first pass can be distinguished when analyzing
 profiler results.
tool-testsuite/test/org/antlr/v4/test/tool/TestPerformance.java