Code/net/minecraft/util/SimpleBitStorage.java

package net.minecraft.util;

import java.util.function.IntConsumer;
import javax.annotation.Nullable;
import org.apache.commons.lang3.Validate;

public class SimpleBitStorage implements BitStorage {
    private static final int[] MAGIC = new int[]{
        -1,
        -1,
        0,
        Integer.MIN_VALUE,
        0,
        0,
        1431655765,
        1431655765,
        0,
        Integer.MIN_VALUE,
        0,
        1,
        858993459,
        858993459,
        0,
        715827882,
        715827882,
        0,
        613566756,
        613566756,
        0,
        Integer.MIN_VALUE,
        0,
        2,
        477218588,
        477218588,
        0,
        429496729,
        429496729,
        0,
        390451572,
        390451572,
        0,
        357913941,
        357913941,
        0,
        330382099,
        330382099,
        0,
        306783378,
        306783378,
        0,
        286331153,
        286331153,
        0,
        Integer.MIN_VALUE,
        0,
        3,
        252645135,
        252645135,
        0,
        238609294,
        238609294,
        0,
        226050910,
        226050910,
        0,
        214748364,
        214748364,
        0,
        204522252,
        204522252,
        0,
        195225786,
        195225786,
        0,
        186737708,
        186737708,
        0,
        178956970,
        178956970,
        0,
        171798691,
        171798691,
        0,
        165191049,
        165191049,
        0,
        159072862,
        159072862,
        0,
        153391689,
        153391689,
        0,
        148102320,
        148102320,
        0,
        143165576,
        143165576,
        0,
        138547332,
        138547332,
        0,
        Integer.MIN_VALUE,
        0,
        4,
        130150524,
        130150524,
        0,
        126322567,
        126322567,
        0,
        122713351,
        122713351,
        0,
        119304647,
        119304647,
        0,
        116080197,
        116080197,
        0,
        113025455,
        113025455,
        0,
        110127366,
        110127366,
        0,
        107374182,
        107374182,
        0,
        104755299,
        104755299,
        0,
        102261126,
        102261126,
        0,
        99882960,
        99882960,
        0,
        97612893,
        97612893,
        0,
        95443717,
        95443717,
        0,
        93368854,
        93368854,
        0,
        91382282,
        91382282,
        0,
        89478485,
        89478485,
        0,
        87652393,
        87652393,
        0,
        85899345,
        85899345,
        0,
        84215045,
        84215045,
        0,
        82595524,
        82595524,
        0,
        81037118,
        81037118,
        0,
        79536431,
        79536431,
        0,
        78090314,
        78090314,
        0,
        76695844,
        76695844,
        0,
        75350303,
        75350303,
        0,
        74051160,
        74051160,
        0,
        72796055,
        72796055,
        0,
        71582788,
        71582788,
        0,
        70409299,
        70409299,
        0,
        69273666,
        69273666,
        0,
        68174084,
        68174084,
        0,
        Integer.MIN_VALUE,
        0,
        5
    };
    private final long[] data;
    private final int bits;
    private final long mask;
    private final int size;
    private final int valuesPerLong;
    private final int divideMul;
    private final int divideAdd;
    private final int divideShift;

    public SimpleBitStorage(int p_198164_, int p_198165_, int[] p_198166_) {
        this(p_198164_, p_198165_);
        int j = 0;

        int i;
        for (i = 0; i <= p_198165_ - this.valuesPerLong; i += this.valuesPerLong) {
            long k = 0L;

            for (int i1 = this.valuesPerLong - 1; i1 >= 0; i1--) {
                k <<= p_198164_;
                k |= p_198166_[i + i1] & this.mask;
            }

            this.data[j++] = k;
        }

        int k1 = p_198165_ - i;
        if (k1 > 0) {
            long l = 0L;

            for (int j1 = k1 - 1; j1 >= 0; j1--) {
                l <<= p_198164_;
                l |= p_198166_[i + j1] & this.mask;
            }

            this.data[j] = l;
        }
    }

    public SimpleBitStorage(int p_184717_, int p_184718_) {
        this(p_184717_, p_184718_, (long[])null);
    }

    public SimpleBitStorage(int p_184724_, int p_184725_, @Nullable long[] p_184726_) {
        Validate.inclusiveBetween(1L, 32L, (long)p_184724_);
        this.size = p_184725_;
        this.bits = p_184724_;
        this.mask = (1L << p_184724_) - 1L;
        this.valuesPerLong = (char)(64 / p_184724_);
        int i = 3 * (this.valuesPerLong - 1);
        this.divideMul = MAGIC[i + 0];
        this.divideAdd = MAGIC[i + 1];
        this.divideShift = MAGIC[i + 2];
        int j = (p_184725_ + this.valuesPerLong - 1) / this.valuesPerLong;
        if (p_184726_ != null) {
            if (p_184726_.length != j) {
                throw new SimpleBitStorage.InitializationException("Invalid length given for storage, got: " + p_184726_.length + " but expected: " + j);
            }

            this.data = p_184726_;
        } else {
            this.data = new long[j];
        }
    }

    private int cellIndex(int p_184740_) {
        long i = Integer.toUnsignedLong(this.divideMul);
        long j = Integer.toUnsignedLong(this.divideAdd);
        return (int)(p_184740_ * i + j >> 32 >> this.divideShift);
    }

    @Override
    public int getAndSet(int p_184731_, int p_184732_) {
        Validate.inclusiveBetween(0L, (long)(this.size - 1), (long)p_184731_);
        Validate.inclusiveBetween(0L, this.mask, (long)p_184732_);
        int i = this.cellIndex(p_184731_);
        long j = this.data[i];
        int k = (p_184731_ - i * this.valuesPerLong) * this.bits;
        int l = (int)(j >> k & this.mask);
        this.data[i] = j & ~(this.mask << k) | (p_184732_ & this.mask) << k;
        return l;
    }

    @Override
    public void set(int p_184742_, int p_184743_) {
        Validate.inclusiveBetween(0L, (long)(this.size - 1), (long)p_184742_);
        Validate.inclusiveBetween(0L, this.mask, (long)p_184743_);
        int i = this.cellIndex(p_184742_);
        long j = this.data[i];
        int k = (p_184742_ - i * this.valuesPerLong) * this.bits;
        this.data[i] = j & ~(this.mask << k) | (p_184743_ & this.mask) << k;
    }

    @Override
    public int get(int p_184729_) {
        Validate.inclusiveBetween(0L, (long)(this.size - 1), (long)p_184729_);
        int i = this.cellIndex(p_184729_);
        long j = this.data[i];
        int k = (p_184729_ - i * this.valuesPerLong) * this.bits;
        return (int)(j >> k & this.mask);
    }

    @Override
    public long[] getRaw() {
        return this.data;
    }

    @Override
    public int getSize() {
        return this.size;
    }

    @Override
    public int getBits() {
        return this.bits;
    }

    @Override
    public void getAll(IntConsumer p_184734_) {
        int i = 0;

        for (long j : this.data) {
            for (int k = 0; k < this.valuesPerLong; k++) {
                p_184734_.accept((int)(j & this.mask));
                j >>= this.bits;
                if (++i >= this.size) {
                    return;
                }
            }
        }
    }

    @Override
    public void unpack(int[] p_198168_) {
        int i = this.data.length;
        int j = 0;

        for (int k = 0; k < i - 1; k++) {
            long l = this.data[k];

            for (int i1 = 0; i1 < this.valuesPerLong; i1++) {
                p_198168_[j + i1] = (int)(l & this.mask);
                l >>= this.bits;
            }

            j += this.valuesPerLong;
        }

        int j1 = this.size - j;
        if (j1 > 0) {
            long k1 = this.data[i - 1];

            for (int l1 = 0; l1 < j1; l1++) {
                p_198168_[j + l1] = (int)(k1 & this.mask);
                k1 >>= this.bits;
            }
        }
    }

    @Override
    public BitStorage copy() {
        return new SimpleBitStorage(this.bits, this.size, (long[])this.data.clone());
    }

    public static class InitializationException extends RuntimeException {
        InitializationException(String p_184746_) {
            super(p_184746_);
        }
    }
}