BitUtil.java

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package org.apache.doris.common.util;

public class BitUtil {

    // Returns the log2 of 'val'. 'val' must be > 0.
    public static int log2Ceiling(long val) {
        // Formula is based on the Long.numberOfLeadingZeros() javadoc comment.
        return 64 - Long.numberOfLeadingZeros(val - 1);
    }

    // Round up 'val' to the nearest power of two. 'val' must be > 0.
    public static long roundUpToPowerOf2(long val) {
        return 1L << log2Ceiling(val);
    }

    // Round up 'val' to the nearest multiple of a power-of-two 'factor'.
    // 'val' must be > 0.
    public static long roundUpToPowerOf2Factor(long val, long factor) {
        return (val + (factor - 1)) & ~(factor - 1);
    }
}