presto-main/src/main/java/io/prestosql/operator/aggregation/histogram/Histogram.java/Histogram/input
class Histogram:    public static void input(Type type, HistogramState state, Block key, int position)
    {
        TypedHistogram typedHistogram = state.get();
        long startSize = typedHistogram.getEstimatedSize();
        typedHistogram.add(position, key, 1L);
        state.addMemoryUsage(typedHistogram.getEstimatedSize() - startSize);
    }