FloatConversion.java

/*
 * Copyright (c) 2023 Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package org.openjdk.bench.java.math;

import java.util.Random;
import java.util.concurrent.TimeUnit;
import org.openjdk.jmh.annotations.*;

@OutputTimeUnit(TimeUnit.MILLISECONDS)
@State(Scope.Thread)
@Warmup(iterations = 5, time = 1)
@Measurement(iterations = 5, time = 1)
@Fork(value = 3)
public class FloatConversion {

    @Param({"2048"})
    public int size;

    public float[]   farr;
    public double[] darr;
    public int[]    f2i;
    public long[]   f2l;
    public int[]    d2i;
    public long[]   d2l;

    @Setup(Level.Trial)
    public void BmSetup() {
        int i = 0;
        Random r = new Random(1024);

        farr = new float[size];
        darr = new double[size];
        f2i  = new int[size];
        f2l  = new long[size];
        d2i  = new int[size];
        d2l  = new long[size];

        for (; i < size - 50; i++) {
            farr[i] = r.nextFloat();
            darr[i] = r.nextDouble();
        }

        // Fill with INF and NaN
        for (; i < size; i++) {
           if (i % 3 == 0) {
            farr[i] = Float.NaN;
            darr[i] = Double.NaN;
           } else if (i % 3 == 1) {
            farr[i] = Float.POSITIVE_INFINITY;
            darr[i] = Double.POSITIVE_INFINITY;
           } else {
            farr[i] = Float.NEGATIVE_INFINITY;
            darr[i] = Double.NEGATIVE_INFINITY;
           }
        }
    }

    @Benchmark
    public int[] floatToInt() {
        for (int i = 0; i < farr.length; i++) {
            f2i[i] = (int) farr[i];
        }
        return f2i;
    }

    @Benchmark
    public long[] floatToLong() {
        for (int i = 0; i < farr.length; i++) {
            f2l[i] = (long) farr[i];
        }
        return f2l;
    }

    @Benchmark
    public int[] doubleToInt() {
        for (int i = 0; i < darr.length; i++) {
            d2i[i] = (int) darr[i];
        }
        return d2i;
    }

    @Benchmark
    public long[] doubleToLong() {
        for (int i = 0; i < darr.length; i++) {
            d2l[i] = (long) darr[i];
        }
        return d2l;
    }
}