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 * (a) the Software, and
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 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
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package com.oracle.truffle.api;

This class contains exact math related methods that are generally useful for dynamic language
implementations.
Since:
0.8 or earlier/**
 * This class contains exact math related methods that are generally useful for dynamic language
 * implementations.
 *
 * @since 0.8 or earlier
 */
public final class ExactMath {

    private ExactMath() {
    }

    
Since:
0.8 or earlier/** @since 0.8 or earlier */
    public static int multiplyHigh(int x, int y) {
        long r = (long) x * (long) y;
        return (int) (r >> 32);
    }

    
Since:
0.8 or earlier/** @since 0.8 or earlier */
    public static int multiplyHighUnsigned(int x, int y) {
        long xl = x & 0xFFFFFFFFL;
        long yl = y & 0xFFFFFFFFL;
        long r = xl * yl;
        return (int) (r >> 32);
    }

    
Since:
0.8 or earlier/** @since 0.8 or earlier */
    public static long multiplyHigh(long x, long y) {
        // Checkstyle: stop
        long x0, y0, z0;
        long x1, y1, z1, z2, t;
        // Checkstyle: resume

        x0 = x & 0xFFFFFFFFL;
        x1 = x >> 32;

        y0 = y & 0xFFFFFFFFL;
        y1 = y >> 32;

        z0 = x0 * y0;
        t = x1 * y0 + (z0 >>> 32);
        z1 = t & 0xFFFFFFFFL;
        z2 = t >> 32;
        z1 += x0 * y1;

        return x1 * y1 + z2 + (z1 >> 32);
    }

    
Since:
0.8 or earlier/** @since 0.8 or earlier */
    public static long multiplyHighUnsigned(long x, long y) {
        // Checkstyle: stop
        long x0, y0, z0;
        long x1, y1, z1, z2, t;
        // Checkstyle: resume

        x0 = x & 0xFFFFFFFFL;
        x1 = x >>> 32;

        y0 = y & 0xFFFFFFFFL;
        y1 = y >>> 32;

        z0 = x0 * y0;
        t = x1 * y0 + (z0 >>> 32);
        z1 = t & 0xFFFFFFFFL;
        z2 = t >>> 32;
        z1 += x0 * y1;

        return x1 * y1 + z2 + (z1 >>> 32);
    }
}