diff -r effb66aab08b -r da026c172c1e src/java.base/share/classes/java/util/random/MRG32k3a.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.base/share/classes/java/util/random/MRG32k3a.java	Thu Nov 14 12:50:08 2019 -0400
@@ -0,0 +1,485 @@
+/*
+ * Copyright (c) 2013, 2019, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package java.util.random;
+
+import java.math.BigInteger;
+import java.util.concurrent.atomic.AtomicLong;
+import java.util.random.RandomGenerator.LeapableGenerator;
+import java.util.random.RandomSupport.AbstractArbitrarilyJumpableGenerator;
+
+/**
+ * A generator of uniform pseudorandom values applicable for use in
+ * (among other contexts) isolated parallel computations that may
+ * generate subtasks.  Class {@link MRG32k3a} implements
+ * interfaces {@link RandomGenerator} and {@link AbstractArbitrarilyJumpableGenerator},
+ * and therefore supports methods for producing pseudorandomly chosen
+ * numbers of type {@code int}, {@code long}, {@code float}, and {@code double}
+ * as well as creating new {@link Xoroshiro128PlusMRG32k3a} objects
+ * by "jumping" or "leaping".
+ * <p>
+ * Instances {@link Xoroshiro128Plus} are <em>not</em> thread-safe.
+ * They are designed to be used so that each thread as its own instance.
+ * The methods {@link #jump} and {@link #leap} and {@link #jumps} and {@link #leaps}
+ * can be used to construct new instances of {@link Xoroshiro128Plus} that traverse
+ * other parts of the state cycle.
+ * <p>
+ * Instances of {@link MRG32k3a} are not cryptographically
+ * secure.  Consider instead using {@link java.security.SecureRandom}
+ * in security-sensitive applications. Additionally,
+ * default-constructed instances do not use a cryptographically random
+ * seed unless the {@linkplain System#getProperty system property}
+ * {@code java.util.secureRandomSeed} is set to {@code true}.
+ *
+ * @since 14
+ */
+public final class MRG32k3a extends AbstractArbitrarilyJumpableGenerator {
+
+    /*
+     * Implementation Overview.
+     *
+     * See http://simul.iro.umontreal.ca/rng/MRG32k3a.c .
+     *
+     * File organization: First the non-public methods that constitute
+     * the main algorithm, then the main public methods, followed by
+     * some custom spliterator classes needed for stream methods.
+     */
+
+    private final static double NORM1 = 2.328306549295728e-10;
+    private final static double NORM2 = 2.328318824698632e-10;
+    private final static double M1 =   4294967087.0;
+    private final static double M2 =   4294944443.0;
+    private final static double A12 =     1403580.0;
+    private final static double A13N =     810728.0;
+    private final static double A21 =      527612.0;
+    private final static double A23N =    1370589.0;
+    private final static int M1_DEFICIT = 209;
+
+    /**
+     * The per-instance state.
+     The seeds for s10, s11, s12 must be integers in [0, m1 - 1] and not all 0.
+     The seeds for s20, s21, s22 must be integers in [0, m2 - 1] and not all 0.
+     */
+    private double s10, s11, s12,
+                   s20, s21, s22;
+
+    /**
+     * The seed generator for default constructors.
+     */
+    private static final AtomicLong DEFAULT_GEN =
+        new AtomicLong(RandomSupport.initialSeed());
+
+    /*
+      32-bits Random number generator U(0,1): MRG32k3a
+      Author: Pierre L'Ecuyer,
+      Source: Good Parameter Sets for Combined Multiple Recursive Random
+           Number Generators,
+           Shorter version in Operations Research,
+           47, 1 (1999), 159--164.
+           ---------------------------------------------------------
+    */
+
+    private void nextState() {
+        /* Component 1 */
+        double p1 = A12 * s11 - A13N * s10;
+        double k1 = p1 / M1;   p1 -= k1 * M1;   if (p1 < 0.0) p1 += M1;
+        s10 = s11;   s11 = s12;   s12 = p1;
+        /* Component 2 */
+        double p2 = A21 * s22 - A23N * s20;
+        double k2 = p2 / M2;   p2 -= k2 * M2;   if (p2 < 0.0) p2 += M2;
+        s20 = s21;   s21 = s22;   s22 = p2;
+    }
+
+
+    /**
+     * The form of nextInt used by IntStream Spliterators.
+     * Exactly the same as long version, except for types.
+     *
+     * @param origin the least value, unless greater than bound
+     * @param bound the upper bound (exclusive), must not equal origin
+     *
+     * @return a pseudorandom value
+     */
+    private int internalNextInt(int origin, int bound) {
+        if (origin < bound) {
+            final int n = bound - origin;
+            final int m = n - 1;
+            if (n > 0) {
+                int r;
+                for (int u = (int)nextDouble() >>> 1;
+                     u + m + ((M1_DEFICIT + 1) >>> 1) - (r = u % n) < 0;
+                     u = (int)nextDouble() >>> 1)
+                    ;
+                return (r + origin);
+            } else {
+                return RandomSupport.boundedNextInt(this, origin, bound);
+            }
+        } else {
+            return nextInt();
+        }
+    }
+
+    private int internalNextInt(int bound) {
+        // Specialize internalNextInt for origin == 0, bound > 0
+        final int n = bound;
+        final int m = n - 1;
+        int r;
+        for (int u = (int)nextDouble() >>> 1;
+             u + m + ((M1_DEFICIT + 1) >>> 1) - (r = u % n) < 0;
+             u = (int)nextDouble() >>> 1)
+            ;
+        return r;
+    }
+
+    /**
+     * All arguments must be known to be nonnegative integral values
+     * less than the appropriate modulus.
+     */
+    private MRG32k3a(double s10, double s11, double s12,
+                     double s20, double s21, double s22) {
+        this.s10 = s10; this.s11 = s11; this.s12 = s12;
+        this.s20 = s20; this.s21 = s21; this.s22 = s22;
+        if ((s10 == 0.0) && (s11 == 0.0) && (s12 == 0.0)) {
+            this.s10 = this.s11 = this.s12 = 12345.0;
+        }
+        if ((s20 == 0.0) && (s21 == 0.0) && (s22 == 0.0)) {
+            this.s20 = this.s21 = this.s21 = 12345.0;
+        }
+    }
+
+    /* ---------------- public methods ---------------- */
+
+    /**
+     * Creates a new MRG32k3a instance using six specified {@code int}
+     * initial seed values. MRG32k3a instances created with the same
+     * seeds in the same program generate identical sequences of values.
+     * If all six seed values are zero, the generator is seeded to a
+     * widely used initialization of MRG32k3a: all six state variables
+     * are set to 12345.
+     *
+     * @param s10 the first seed value for the first subgenerator
+     * @param s11 the second seed value for the first subgenerator
+     * @param s12 the third seed value for the first subgenerator
+     * @param s20 the first seed value for the second subgenerator
+     * @param s21 the second seed value for the second subgenerator
+     * @param s22 the third seed value for the second subgenerator
+     */
+    public MRG32k3a(int s10, int s11, int s12,
+                    int s20, int s21, int s22) {
+        this(((double)(((long)s10) & 0x00000000ffffffffL)) % M1,
+             ((double)(((long)s11) & 0x00000000ffffffffL)) % M1,
+             ((double)(((long)s12) & 0x00000000ffffffffL)) % M1,
+             ((double)(((long)s20) & 0x00000000ffffffffL)) % M2,
+             ((double)(((long)s21) & 0x00000000ffffffffL)) % M2,
+             ((double)(((long)s22) & 0x00000000ffffffffL)) % M2);
+    }
+
+    /**
+     * Creates a new MRG32k3a instance using the specified
+     * initial seed. MRG32k3a instances created with the same
+     * seed in the same program generate identical sequences of values.
+     * An argument of 0 seeds the generator to a widely used initialization
+     * of MRG32k3a: all six state variables are set to 12345.
+     *
+     * @param seed the initial seed
+     */
+    public MRG32k3a(long seed) {
+        this((double)((seed & 0x7FF) + 12345),
+             (double)(((seed >>> 11) & 0x7FF) + 12345),
+             (double)(((seed >>> 22) & 0x7FF) + 12345),
+             (double)(((seed >>> 33) & 0x7FF) + 12345),
+             (double)(((seed >>> 44) & 0x7FF) + 12345),
+             (double)((seed >>> 55) + 12345));
+    }
+
+    /**
+     * Creates a new MRG32k3a instance that is likely to
+     * generate sequences of values that are statistically independent
+     * of those of any other instances in the current program; and
+     * may, and typically does, vary across program invocations.
+     */
+    public MRG32k3a() {
+        this(DEFAULT_GEN.getAndAdd(RandomSupport.GOLDEN_RATIO_64));
+    }
+
+    /**
+     * Creates a new instance of {@link Xoshiro256StarStar} using the specified array of
+     * initial seed bytes. Instances of {@link Xoshiro256StarStar} created with the same
+     * seed array in the same program execution generate identical sequences of values.
+     *
+     * @param seed the initial seed
+     */
+    public MRG32k3a(byte[] seed) {
+        // Convert the seed to 6 int values.
+        int[] data = RandomSupport.convertSeedBytesToInts(seed, 6, 0);
+        int s10 = data[0], s11 = data[1], s12 = data[2];
+        int s20 = data[3], s21 = data[4], s22 = data[5];
+        this.s10 = ((double)(((long)s10) & 0x00000000ffffffffL)) % M1;
+        this.s11 = ((double)(((long)s11) & 0x00000000ffffffffL)) % M1;
+        this.s12 = ((double)(((long)s12) & 0x00000000ffffffffL)) % M1;
+        this.s20 = ((double)(((long)s20) & 0x00000000ffffffffL)) % M2;
+        this.s21 = ((double)(((long)s21) & 0x00000000ffffffffL)) % M2;
+        this.s22 = ((double)(((long)s22) & 0x00000000ffffffffL)) % M2;
+        if ((s10 == 0.0) && (s11 == 0.0) && (s12 == 0.0)) {
+            this.s10 = this.s11 = this.s12 = 12345.0;
+        }
+        if ((s20 == 0.0) && (s21 == 0.0) && (s22 == 0.0)) {
+            this.s20 = this.s21 = this.s21 = 12345.0;
+        }
+    }
+
+    public MRG32k3a copy() {
+        return new MRG32k3a(s10, s11, s12, s20, s21, s22);
+    }
+
+    /**
+     * Returns a pseudorandom {@code double} value between zero
+     * (exclusive) and one (exclusive).
+     *
+     * @return a pseudorandom {@code double} value between zero
+     *         (exclusive) and one (exclusive)
+     */
+    public double nextOpenDouble() {
+        nextState();
+        double p1 = s12, p2 = s22;
+        if (p1 <= p2)
+            return ((p1 - p2 + M1) * NORM1);
+        else
+            return ((p1 - p2) * NORM1);
+    }
+
+    /**
+     * Returns a pseudorandom {@code double} value between zero
+     * (inclusive) and one (exclusive).
+     *
+     * @return a pseudorandom {@code double} value between zero
+     *         (inclusive) and one (exclusive)
+     */
+    public double nextDouble() {
+        nextState();
+        double p1 = s12, p2 = s22;
+        final double p = p1 * NORM1 - p2 * NORM2;
+        if (p < 0.0) return (p + 1.0);
+        else return p;
+    }
+
+
+    /**
+     * Returns a pseudorandom {@code float} value between zero
+     * (inclusive) and one (exclusive).
+     *
+     * @return a pseudorandom {@code float} value between zero
+     *         (inclusive) and one (exclusive)
+     */
+    public float nextFloat() {
+        return (float)nextDouble();
+    }
+
+    /**
+     * Returns a pseudorandom {@code int} value.
+     *
+     * @return a pseudorandom {@code int} value
+     */
+    public int nextInt() {
+        return (internalNextInt(0x10000) << 16) | internalNextInt(0x10000);
+    }
+
+    /**
+     * Returns a pseudorandom {@code long} value.
+     *
+     * @return a pseudorandom {@code long} value
+     */
+
+    public long nextLong() {
+         return (((long)internalNextInt(0x200000) << 43) |
+                ((long)internalNextInt(0x200000) << 22) |
+                ((long)internalNextInt(0x400000)));
+    }
+
+    // Period is (m1**3 - 1)(m2**3 - 1)/2, or approximately 2**191.
+    static BigInteger calculateThePeriod() {
+        BigInteger bigm1 = BigInteger.valueOf((long)M1);
+        BigInteger bigm2 = BigInteger.valueOf((long)M2);
+        BigInteger t1 = bigm1.multiply(bigm1).multiply(bigm1).subtract(BigInteger.ONE);
+        BigInteger t2 = bigm2.multiply(bigm2).multiply(bigm2).subtract(BigInteger.ONE);
+        return t1.shiftRight(1).multiply(t2);
+    }
+
+    static final BigInteger PERIOD = calculateThePeriod();
+
+    public BigInteger period() {
+        return PERIOD;
+    }
+
+    // Jump and leap distances recommended in Section 1.3 of this paper:
+    // Pierre L'Ecuyer, Richard Simard, E. Jack Chen, and W. David Kelton.
+    // An Object-Oriented Random-Number Package with Many Long Streams and Substreams.
+    // Operations Research 50, 6 (Nov--Dec 2002), 1073--1075.
+
+    public double defaultJumpDistance() {
+        return 0x1.0p76;   // 2**76
+    }
+
+    public double defaultLeapDistance() {
+        return 0x1.0p127;   // 2**127
+    }
+
+    public void jump(double distance) {
+        if (distance < 0.0 || Double.isInfinite(distance) || distance != Math.floor(distance))
+            throw new IllegalArgumentException("jump distance must be a nonnegative finite integer");
+            // We will compute a jump transformation (s => M s) for each LCG.
+            // We initialize each transformation to the identity transformation.
+            // Each will be turned into the d'th power of the corresponding base transformation.
+        long m1_00 = 1, m1_01 = 0, m1_02 = 0,
+             m1_10 = 0, m1_11 = 1, m1_12 = 0,
+             m1_20 = 0, m1_21 = 0, m1_22 = 1;
+        long m2_00 = 1, m2_01 = 0, m2_02 = 0,
+             m2_10 = 0, m2_11 = 1, m2_12 = 0,
+             m2_20 = 0, m2_21 = 0, m2_22 = 1;
+        // These are the base transformations, which will be repeatedly squared,
+        // and composed with the computed transformations for each 1-bit in distance.
+        long t1_00 = 0,           t1_01 = 1,         t1_02 = 0,
+             t1_10 = 0,           t1_11 = 0,         t1_12 = 1,
+             t1_20 = -(long)A13N, t1_21 = (long)A12, t1_22 = 0;
+        long t2_00 = 0,           t2_01 = 1,         t2_02 = 0,
+             t2_10 = 0,           t2_11 = 0,         t2_12 = 1,
+             t2_20 = -(long)A23N, t2_21 = (long)A21, t2_22 = 0;
+        while (distance > 0.0) {
+            final double dhalf = 0.5 * distance;
+            if (Math.floor(dhalf) != dhalf) {
+                // distance is odd: accumulate current squaring
+                final long n1_00 = m1_00 * t1_00 + m1_01 * t1_10 + m1_02 * t1_20;
+                final long n1_01 = m1_00 * t1_01 + m1_01 * t1_11 + m1_02 * t1_21;
+                final long n1_02 = m1_00 * t1_02 + m1_01 * t1_12 + m1_02 * t1_22;
+                final long n1_10 = m1_10 * t1_00 + m1_11 * t1_10 + m1_12 * t1_20;
+                final long n1_11 = m1_10 * t1_01 + m1_11 * t1_11 + m1_12 * t1_21;
+                final long n1_12 = m1_10 * t1_02 + m1_11 * t1_12 + m1_12 * t1_22;
+                final long n1_20 = m1_20 * t1_00 + m1_21 * t1_10 + m1_22 * t1_20;
+                final long n1_21 = m1_20 * t1_01 + m1_21 * t1_11 + m1_22 * t1_21;
+                final long n1_22 = m1_20 * t1_02 + m1_21 * t1_12 + m1_22 * t1_22;
+                m1_00 = Math.floorMod(n1_00, (long)M1);
+                m1_01 = Math.floorMod(n1_01, (long)M1);
+                m1_02 = Math.floorMod(n1_02, (long)M1);
+                m1_10 = Math.floorMod(n1_10, (long)M1);
+                m1_11 = Math.floorMod(n1_11, (long)M1);
+                m1_12 = Math.floorMod(n1_12, (long)M1);
+                m1_20 = Math.floorMod(n1_20, (long)M1);
+                m1_21 = Math.floorMod(n1_21, (long)M1);
+                m1_22 = Math.floorMod(n1_22, (long)M1);
+                final long n2_00 = m2_00 * t2_00 + m2_01 * t2_10 + m2_02 * t2_20;
+                final long n2_01 = m2_00 * t2_01 + m2_01 * t2_11 + m2_02 * t2_21;
+                final long n2_02 = m2_00 * t2_02 + m2_01 * t2_12 + m2_02 * t2_22;
+                final long n2_10 = m2_10 * t2_00 + m2_11 * t2_10 + m2_12 * t2_20;
+                final long n2_11 = m2_10 * t2_01 + m2_11 * t2_11 + m2_12 * t2_21;
+                final long n2_12 = m2_10 * t2_02 + m2_11 * t2_12 + m2_12 * t2_22;
+                final long n2_20 = m2_20 * t2_00 + m2_21 * t2_10 + m2_22 * t2_20;
+                final long n2_21 = m2_20 * t2_01 + m2_21 * t2_11 + m2_22 * t2_21;
+                final long n2_22 = m2_20 * t2_02 + m2_21 * t2_12 + m2_22 * t2_22;
+                m2_00 = Math.floorMod(n2_00, (long)M2);
+                m2_01 = Math.floorMod(n2_01, (long)M2);
+                m2_02 = Math.floorMod(n2_02, (long)M2);
+                m2_10 = Math.floorMod(n2_10, (long)M2);
+                m2_11 = Math.floorMod(n2_11, (long)M2);
+                m2_12 = Math.floorMod(n2_12, (long)M2);
+                m2_20 = Math.floorMod(n2_20, (long)M2);
+                m2_21 = Math.floorMod(n2_21, (long)M2);
+                m2_22 = Math.floorMod(n2_22, (long)M2);
+            }
+            // Square the base transformations.
+            {
+                final long z1_00 = m1_00 * m1_00 + m1_01 * m1_10 + m1_02 * m1_20;
+                final long z1_01 = m1_00 * m1_01 + m1_01 * m1_11 + m1_02 * m1_21;
+                final long z1_02 = m1_00 * m1_02 + m1_01 * m1_12 + m1_02 * m1_22;
+                final long z1_10 = m1_10 * m1_00 + m1_11 * m1_10 + m1_12 * m1_20;
+                final long z1_11 = m1_10 * m1_01 + m1_11 * m1_11 + m1_12 * m1_21;
+                final long z1_12 = m1_10 * m1_02 + m1_11 * m1_12 + m1_12 * m1_22;
+                final long z1_20 = m1_20 * m1_00 + m1_21 * m1_10 + m1_22 * m1_20;
+                final long z1_21 = m1_20 * m1_01 + m1_21 * m1_11 + m1_22 * m1_21;
+                final long z1_22 = m1_20 * m1_02 + m1_21 * m1_12 + m1_22 * m1_22;
+                m1_00 = Math.floorMod(z1_00, (long)M1);
+                m1_01 = Math.floorMod(z1_01, (long)M1);
+                m1_02 = Math.floorMod(z1_02, (long)M1);
+                m1_10 = Math.floorMod(z1_10, (long)M1);
+                m1_11 = Math.floorMod(z1_11, (long)M1);
+                m1_12 = Math.floorMod(z1_12, (long)M1);
+                m1_20 = Math.floorMod(z1_20, (long)M1);
+                m1_21 = Math.floorMod(z1_21, (long)M1);
+                m1_22 = Math.floorMod(z1_22, (long)M1);
+                final long z2_00 = m2_00 * m2_00 + m2_01 * m2_10 + m2_02 * m2_20;
+                final long z2_01 = m2_00 * m2_01 + m2_01 * m2_11 + m2_02 * m2_21;
+                final long z2_02 = m2_00 * m2_02 + m2_01 * m2_12 + m2_02 * m2_22;
+                final long z2_10 = m2_10 * m2_00 + m2_11 * m2_10 + m2_12 * m2_20;
+                final long z2_11 = m2_10 * m2_01 + m2_11 * m2_11 + m2_12 * m2_21;
+                final long z2_12 = m2_10 * m2_02 + m2_11 * m2_12 + m2_12 * m2_22;
+                final long z2_20 = m2_20 * m2_00 + m2_21 * m2_10 + m2_22 * m2_20;
+                final long z2_21 = m2_20 * m2_01 + m2_21 * m2_11 + m2_22 * m2_21;
+                final long z2_22 = m2_20 * m2_02 + m2_21 * m2_12 + m2_22 * m2_22;
+                m2_00 = Math.floorMod(z2_00, (long)M2);
+                m2_01 = Math.floorMod(z2_01, (long)M2);
+                m2_02 = Math.floorMod(z2_02, (long)M2);
+                m2_10 = Math.floorMod(z2_10, (long)M2);
+                m2_11 = Math.floorMod(z2_11, (long)M2);
+                m2_12 = Math.floorMod(z2_12, (long)M2);
+                m2_20 = Math.floorMod(z2_20, (long)M2);
+                m2_21 = Math.floorMod(z2_21, (long)M2);
+                m2_22 = Math.floorMod(z2_22, (long)M2);
+            }
+            // Divide distance by 2.
+            distance = dhalf;
+        }
+        final long w10 = m1_00 * (long)s10 + m1_01 * (long)s11 + m1_02 * (long)s12;
+        final long w11 = m1_10 * (long)s10 + m1_11 * (long)s11 + m1_12 * (long)s12;
+        final long w12 = m1_20 * (long)s10 + m1_21 * (long)s11 + m1_22 * (long)s12;
+        s10 = Math.floorMod(w10, (long)M1);
+        s11 = Math.floorMod(w11, (long)M1);
+        s12 = Math.floorMod(w12, (long)M1);
+        final long w20 = m2_00 * (long)s20 + m2_01 * (long)s21 + m2_02 * (long)s22;
+        final long w21 = m2_10 * (long)s20 + m2_11 * (long)s21 + m2_12 * (long)s22;
+        final long w22 = m2_20 * (long)s20 + m2_21 * (long)s21 + m2_22 * (long)s22;
+        s20 = Math.floorMod(w20, (long)M2);
+        s21 = Math.floorMod(w21, (long)M2);
+        s22 = Math.floorMod(w22, (long)M2);
+    }
+
+    /**
+     * Alter the state of this pseudorandom number generator so as to
+     * jump forward a distance equal to 2<sup>{@code logDistance}</sup>
+     * within its state cycle.
+     *
+     * @param logDistance the base-2 logarithm of the distance to jump
+     *        forward within the state cycle.  Must be non-negative and
+     *        not greater than 192.
+     *
+     * @throws IllegalArgumentException if {@code logDistance} is
+     *         less than zero or 2<sup>{@code logDistance}</sup> is
+     *         greater than the period of this generator
+     */
+    public void jumpPowerOfTwo(int logDistance) {
+        if (logDistance < 0 || logDistance > 192)
+            throw new IllegalArgumentException("logDistance must be non-negative and not greater than 192");
+        jump(Math.scalb(1.0, logDistance));
+    }
+
+}