diff -r d935d42f6d93 -r 9548f8d846e9 jdk/src/java.base/share/classes/java/util/concurrent/atomic/AtomicLongArray.java
--- a/jdk/src/java.base/share/classes/java/util/concurrent/atomic/AtomicLongArray.java	Fri Jul 15 13:59:58 2016 -0700
+++ b/jdk/src/java.base/share/classes/java/util/concurrent/atomic/AtomicLongArray.java	Fri Jul 15 14:04:09 2016 -0700
@@ -35,43 +35,24 @@
 
 package java.util.concurrent.atomic;
 
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.VarHandle;
 import java.util.function.LongBinaryOperator;
 import java.util.function.LongUnaryOperator;
 
 /**
  * A {@code long} array in which elements may be updated atomically.
- * See the {@link java.util.concurrent.atomic} package specification
- * for description of the properties of atomic variables.
+ * See the {@link VarHandle} specification for descriptions of the
+ * properties of atomic accesses.
  * @since 1.5
  * @author Doug Lea
  */
 public class AtomicLongArray implements java.io.Serializable {
     private static final long serialVersionUID = -2308431214976778248L;
-
-    private static final jdk.internal.misc.Unsafe U = jdk.internal.misc.Unsafe.getUnsafe();
-    private static final int ABASE;
-    private static final int ASHIFT;
+    private static final VarHandle AA
+        = MethodHandles.arrayElementVarHandle(long[].class);
     private final long[] array;
 
-    static {
-        ABASE = U.arrayBaseOffset(long[].class);
-        int scale = U.arrayIndexScale(long[].class);
-        if ((scale & (scale - 1)) != 0)
-            throw new Error("array index scale not a power of two");
-        ASHIFT = 31 - Integer.numberOfLeadingZeros(scale);
-    }
-
-    private long checkedByteOffset(int i) {
-        if (i < 0 || i >= array.length)
-            throw new IndexOutOfBoundsException("index " + i);
-
-        return byteOffset(i);
-    }
-
-    private static long byteOffset(int i) {
-        return ((long) i << ASHIFT) + ABASE;
-    }
-
     /**
      * Creates a new AtomicLongArray of the given length, with all
      * elements initially zero.
@@ -104,147 +85,155 @@
     }
 
     /**
-     * Gets the current value at position {@code i}.
+     * Returns the current value of the element at index {@code i},
+     * with memory effects as specified by {@link VarHandle#getVolatile}.
      *
      * @param i the index
      * @return the current value
      */
     public final long get(int i) {
-        return getRaw(checkedByteOffset(i));
-    }
-
-    private long getRaw(long offset) {
-        return U.getLongVolatile(array, offset);
+        return (long)AA.getVolatile(array, i);
     }
 
     /**
-     * Sets the element at position {@code i} to the given value.
+     * Sets the element at index {@code i} to {@code newValue},
+     * with memory effects as specified by {@link VarHandle#setVolatile}.
      *
      * @param i the index
      * @param newValue the new value
      */
     public final void set(int i, long newValue) {
-        U.putLongVolatile(array, checkedByteOffset(i), newValue);
+        AA.setVolatile(array, i, newValue);
     }
 
     /**
-     * Eventually sets the element at position {@code i} to the given value.
+     * Sets the element at index {@code i} to {@code newValue},
+     * with memory effects as specified by {@link VarHandle#setRelease}.
      *
      * @param i the index
      * @param newValue the new value
      * @since 1.6
      */
     public final void lazySet(int i, long newValue) {
-        U.putLongRelease(array, checkedByteOffset(i), newValue);
+        AA.setRelease(array, i, newValue);
     }
 
     /**
-     * Atomically sets the element at position {@code i} to the given value
-     * and returns the old value.
+     * Atomically sets the element at index {@code i} to {@code
+     * newValue} and returns the old value,
+     * with memory effects as specified by {@link VarHandle#getAndSet}.
      *
      * @param i the index
      * @param newValue the new value
      * @return the previous value
      */
     public final long getAndSet(int i, long newValue) {
-        return U.getAndSetLong(array, checkedByteOffset(i), newValue);
+        return (long)AA.getAndSet(array, i, newValue);
     }
 
     /**
-     * Atomically sets the element at position {@code i} to the given
-     * updated value if the current value {@code ==} the expected value.
+     * Atomically sets the element at index {@code i} to {@code newValue}
+     * if the element's current value {@code == expectedValue},
+     * with memory effects as specified by {@link VarHandle#compareAndSet}.
      *
      * @param i the index
-     * @param expect the expected value
-     * @param update the new value
+     * @param expectedValue the expected value
+     * @param newValue the new value
      * @return {@code true} if successful. False return indicates that
      * the actual value was not equal to the expected value.
      */
-    public final boolean compareAndSet(int i, long expect, long update) {
-        return compareAndSetRaw(checkedByteOffset(i), expect, update);
-    }
-
-    private boolean compareAndSetRaw(long offset, long expect, long update) {
-        return U.compareAndSwapLong(array, offset, expect, update);
+    public final boolean compareAndSet(int i, long expectedValue, long newValue) {
+        return AA.compareAndSet(array, i, expectedValue, newValue);
     }
 
     /**
-     * Atomically sets the element at position {@code i} to the given
-     * updated value if the current value {@code ==} the expected value.
-     *
-     * <p><a href="package-summary.html#weakCompareAndSet">May fail
-     * spuriously and does not provide ordering guarantees</a>, so is
-     * only rarely an appropriate alternative to {@code compareAndSet}.
+     * Possibly atomically sets the element at index {@code i} to
+     * {@code newValue} if the element's current value {@code == expectedValue},
+     * with memory effects as specified by {@link VarHandle#weakCompareAndSet}.
      *
      * @param i the index
-     * @param expect the expected value
-     * @param update the new value
+     * @param expectedValue the expected value
+     * @param newValue the new value
      * @return {@code true} if successful
      */
-    public final boolean weakCompareAndSet(int i, long expect, long update) {
-        return compareAndSet(i, expect, update);
+    public final boolean weakCompareAndSet(int i, long expectedValue, long newValue) {
+        return AA.weakCompareAndSet(array, i, expectedValue, newValue);
     }
 
     /**
-     * Atomically increments by one the element at index {@code i}.
+     * Atomically increments the value of the element at index {@code i},
+     * with memory effects as specified by {@link VarHandle#getAndAdd}.
+     *
+     * <p>Equivalent to {@code getAndAdd(i, 1)}.
      *
      * @param i the index
      * @return the previous value
      */
     public final long getAndIncrement(int i) {
-        return getAndAdd(i, 1);
+        return (long)AA.getAndAdd(array, i, 1L);
     }
 
     /**
-     * Atomically decrements by one the element at index {@code i}.
+     * Atomically decrements the value of the element at index {@code i},
+     * with memory effects as specified by {@link VarHandle#getAndAdd}.
+     *
+     * <p>Equivalent to {@code getAndAdd(i, -1)}.
      *
      * @param i the index
      * @return the previous value
      */
     public final long getAndDecrement(int i) {
-        return getAndAdd(i, -1);
+        return (long)AA.getAndAdd(array, i, -1L);
     }
 
     /**
-     * Atomically adds the given value to the element at index {@code i}.
+     * Atomically adds the given value to the element at index {@code i},
+     * with memory effects as specified by {@link VarHandle#getAndAdd}.
      *
      * @param i the index
      * @param delta the value to add
      * @return the previous value
      */
     public final long getAndAdd(int i, long delta) {
-        return U.getAndAddLong(array, checkedByteOffset(i), delta);
+        return (long)AA.getAndAdd(array, i, delta);
     }
 
     /**
-     * Atomically increments by one the element at index {@code i}.
+     * Atomically increments the value of the element at index {@code i},
+     * with memory effects as specified by {@link VarHandle#addAndGet}.
+     *
+     * <p>Equivalent to {@code addAndGet(i, 1)}.
      *
      * @param i the index
      * @return the updated value
      */
     public final long incrementAndGet(int i) {
-        return getAndAdd(i, 1) + 1;
+        return (long)AA.addAndGet(array, i, 1L);
     }
 
     /**
-     * Atomically decrements by one the element at index {@code i}.
+     * Atomically decrements the value of the element at index {@code i},
+     * with memory effects as specified by {@link VarHandle#addAndGet}.
+     *
+     * <p>Equivalent to {@code addAndGet(i, -1)}.
      *
      * @param i the index
      * @return the updated value
      */
     public final long decrementAndGet(int i) {
-        return getAndAdd(i, -1) - 1;
+        return (long)AA.addAndGet(array, i, -1L);
     }
 
     /**
-     * Atomically adds the given value to the element at index {@code i}.
+     * Atomically adds the given value to the element at index {@code i},
+     * with memory effects as specified by {@link VarHandle#addAndGet}.
      *
      * @param i the index
      * @param delta the value to add
      * @return the updated value
      */
     public long addAndGet(int i, long delta) {
-        return getAndAdd(i, delta) + delta;
+        return (long)AA.addAndGet(array, i, delta);
     }
 
     /**
@@ -259,13 +248,14 @@
      * @since 1.8
      */
     public final long getAndUpdate(int i, LongUnaryOperator updateFunction) {
-        long offset = checkedByteOffset(i);
-        long prev, next;
-        do {
-            prev = getRaw(offset);
-            next = updateFunction.applyAsLong(prev);
-        } while (!compareAndSetRaw(offset, prev, next));
-        return prev;
+        long prev = get(i), next = 0L;
+        for (boolean haveNext = false;;) {
+            if (!haveNext)
+                next = updateFunction.applyAsLong(prev);
+            if (weakCompareAndSetVolatile(i, prev, next))
+                return prev;
+            haveNext = (prev == (prev = get(i)));
+        }
     }
 
     /**
@@ -280,23 +270,25 @@
      * @since 1.8
      */
     public final long updateAndGet(int i, LongUnaryOperator updateFunction) {
-        long offset = checkedByteOffset(i);
-        long prev, next;
-        do {
-            prev = getRaw(offset);
-            next = updateFunction.applyAsLong(prev);
-        } while (!compareAndSetRaw(offset, prev, next));
-        return next;
+        long prev = get(i), next = 0L;
+        for (boolean haveNext = false;;) {
+            if (!haveNext)
+                next = updateFunction.applyAsLong(prev);
+            if (weakCompareAndSetVolatile(i, prev, next))
+                return next;
+            haveNext = (prev == (prev = get(i)));
+        }
     }
 
     /**
      * Atomically updates the element at index {@code i} with the
-     * results of applying the given function to the current and
-     * given values, returning the previous value. The function should
-     * be side-effect-free, since it may be re-applied when attempted
+     * results of applying the given function to the current and given
+     * values, returning the previous value. The function should be
+     * side-effect-free, since it may be re-applied when attempted
      * updates fail due to contention among threads.  The function is
-     * applied with the current value at index {@code i} as its first
-     * argument, and the given update as the second argument.
+     * applied with the current value of the element at index {@code i}
+     * as its first argument, and the given update as the second
+     * argument.
      *
      * @param i the index
      * @param x the update value
@@ -306,23 +298,25 @@
      */
     public final long getAndAccumulate(int i, long x,
                                       LongBinaryOperator accumulatorFunction) {
-        long offset = checkedByteOffset(i);
-        long prev, next;
-        do {
-            prev = getRaw(offset);
-            next = accumulatorFunction.applyAsLong(prev, x);
-        } while (!compareAndSetRaw(offset, prev, next));
-        return prev;
+        long prev = get(i), next = 0L;
+        for (boolean haveNext = false;;) {
+            if (!haveNext)
+                next = accumulatorFunction.applyAsLong(prev, x);
+            if (weakCompareAndSetVolatile(i, prev, next))
+                return prev;
+            haveNext = (prev == (prev = get(i)));
+        }
     }
 
     /**
      * Atomically updates the element at index {@code i} with the
-     * results of applying the given function to the current and
-     * given values, returning the updated value. The function should
-     * be side-effect-free, since it may be re-applied when attempted
+     * results of applying the given function to the current and given
+     * values, returning the updated value. The function should be
+     * side-effect-free, since it may be re-applied when attempted
      * updates fail due to contention among threads.  The function is
-     * applied with the current value at index {@code i} as its first
-     * argument, and the given update as the second argument.
+     * applied with the current value of the element at index {@code i}
+     * as its first argument, and the given update as the second
+     * argument.
      *
      * @param i the index
      * @param x the update value
@@ -332,13 +326,14 @@
      */
     public final long accumulateAndGet(int i, long x,
                                       LongBinaryOperator accumulatorFunction) {
-        long offset = checkedByteOffset(i);
-        long prev, next;
-        do {
-            prev = getRaw(offset);
-            next = accumulatorFunction.applyAsLong(prev, x);
-        } while (!compareAndSetRaw(offset, prev, next));
-        return next;
+        long prev = get(i), next = 0L;
+        for (boolean haveNext = false;;) {
+            if (!haveNext)
+                next = accumulatorFunction.applyAsLong(prev, x);
+            if (weakCompareAndSetVolatile(i, prev, next))
+                return next;
+            haveNext = (prev == (prev = get(i)));
+        }
     }
 
     /**
@@ -353,11 +348,189 @@
         StringBuilder b = new StringBuilder();
         b.append('[');
         for (int i = 0; ; i++) {
-            b.append(getRaw(byteOffset(i)));
+            b.append(get(i));
             if (i == iMax)
                 return b.append(']').toString();
             b.append(',').append(' ');
         }
     }
 
+    // jdk9
+
+    /**
+     * Returns the current value of the element at index {@code i},
+     * with memory semantics of reading as if the variable was declared
+     * non-{@code volatile}.
+     *
+     * @param i the index
+     * @return the value
+     * @since 9
+     */
+    public final long getPlain(int i) {
+        return (long)AA.get(array, i);
+    }
+
+    /**
+     * Sets the element at index {@code i} to {@code newValue},
+     * with memory semantics of setting as if the variable was
+     * declared non-{@code volatile} and non-{@code final}.
+     *
+     * @param i the index
+     * @param newValue the new value
+     * @since 9
+     */
+    public final void setPlain(int i, long newValue) {
+        AA.set(array, i, newValue);
+    }
+
+    /**
+     * Returns the current value of the element at index {@code i},
+     * with memory effects as specified by {@link VarHandle#getOpaque}.
+     *
+     * @param i the index
+     * @return the value
+     * @since 9
+     */
+    public final long getOpaque(int i) {
+        return (long)AA.getOpaque(array, i);
+    }
+
+    /**
+     * Sets the element at index {@code i} to {@code newValue},
+     * with memory effects as specified by {@link VarHandle#setOpaque}.
+     *
+     * @param i the index
+     * @param newValue the new value
+     * @since 9
+     */
+    public final void setOpaque(int i, long newValue) {
+        AA.setOpaque(array, i, newValue);
+    }
+
+    /**
+     * Returns the current value of the element at index {@code i},
+     * with memory effects as specified by {@link VarHandle#getAcquire}.
+     *
+     * @param i the index
+     * @return the value
+     * @since 9
+     */
+    public final long getAcquire(int i) {
+        return (long)AA.getAcquire(array, i);
+    }
+
+    /**
+     * Sets the element at index {@code i} to {@code newValue},
+     * with memory effects as specified by {@link VarHandle#setRelease}.
+     *
+     * @param i the index
+     * @param newValue the new value
+     * @since 9
+     */
+    public final void setRelease(int i, long newValue) {
+        AA.setRelease(array, i, newValue);
+    }
+
+    /**
+     * Atomically sets the element at index {@code i} to {@code newValue}
+     * if the element's current value, referred to as the <em>witness
+     * value</em>, {@code == expectedValue},
+     * with memory effects as specified by
+     * {@link VarHandle#compareAndExchange}.
+     *
+     * @param i the index
+     * @param expectedValue the expected value
+     * @param newValue the new value
+     * @return the witness value, which will be the same as the
+     * expected value if successful
+     * @since 9
+     */
+    public final long compareAndExchange(int i, long expectedValue, long newValue) {
+        return (long)AA.compareAndExchange(array, i, expectedValue, newValue);
+    }
+
+    /**
+     * Atomically sets the element at index {@code i} to {@code newValue}
+     * if the element's current value, referred to as the <em>witness
+     * value</em>, {@code == expectedValue},
+     * with memory effects as specified by
+     * {@link VarHandle#compareAndExchangeAcquire}.
+     *
+     * @param i the index
+     * @param expectedValue the expected value
+     * @param newValue the new value
+     * @return the witness value, which will be the same as the
+     * expected value if successful
+     * @since 9
+     */
+    public final long compareAndExchangeAcquire(int i, long expectedValue, long newValue) {
+        return (long)AA.compareAndExchangeAcquire(array, i, expectedValue, newValue);
+    }
+
+    /**
+     * Atomically sets the element at index {@code i} to {@code newValue}
+     * if the element's current value, referred to as the <em>witness
+     * value</em>, {@code == expectedValue},
+     * with memory effects as specified by
+     * {@link VarHandle#compareAndExchangeRelease}.
+     *
+     * @param i the index
+     * @param expectedValue the expected value
+     * @param newValue the new value
+     * @return the witness value, which will be the same as the
+     * expected value if successful
+     * @since 9
+     */
+    public final long compareAndExchangeRelease(int i, long expectedValue, long newValue) {
+        return (long)AA.compareAndExchangeRelease(array, i, expectedValue, newValue);
+    }
+
+    /**
+     * Possibly atomically sets the element at index {@code i} to
+     * {@code newValue} if the element's current value {@code == expectedValue},
+     * with memory effects as specified by
+     * {@link VarHandle#weakCompareAndSetVolatile}.
+     *
+     * @param i the index
+     * @param expectedValue the expected value
+     * @param newValue the new value
+     * @return {@code true} if successful
+     * @since 9
+     */
+    public final boolean weakCompareAndSetVolatile(int i, long expectedValue, long newValue) {
+        return AA.weakCompareAndSetVolatile(array, i, expectedValue, newValue);
+    }
+
+    /**
+     * Possibly atomically sets the element at index {@code i} to
+     * {@code newValue} if the element's current value {@code == expectedValue},
+     * with memory effects as specified by
+     * {@link VarHandle#weakCompareAndSetAcquire}.
+     *
+     * @param i the index
+     * @param expectedValue the expected value
+     * @param newValue the new value
+     * @return {@code true} if successful
+     * @since 9
+     */
+    public final boolean weakCompareAndSetAcquire(int i, long expectedValue, long newValue) {
+        return AA.weakCompareAndSetAcquire(array, i, expectedValue, newValue);
+    }
+
+    /**
+     * Possibly atomically sets the element at index {@code i} to
+     * {@code newValue} if the element's current value {@code == expectedValue},
+     * with memory effects as specified by
+     * {@link VarHandle#weakCompareAndSetRelease}.
+     *
+     * @param i the index
+     * @param expectedValue the expected value
+     * @param newValue the new value
+     * @return {@code true} if successful
+     * @since 9
+     */
+    public final boolean weakCompareAndSetRelease(int i, long expectedValue, long newValue) {
+        return AA.weakCompareAndSetRelease(array, i, expectedValue, newValue);
+    }
+
 }