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verified gcc-4.6.4.tar.bz2.sig;
imported gcc-4.6.4 source tree from verified upstream tarball.

downloading a git-generated archive based on the 'upstream' tag
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if you have obtained the source via the command 'git clone',
however, do note that line-endings of files in your working
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12 files changed, 2735 insertions, 0 deletions

diff --git a/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicBoolean.java b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicBoolean.java
new file mode 100644
index 000000000..bd823bd2c
--- /dev/null
+++ b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicBoolean.java
@@ -0,0 +1,133 @@
+/*
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/licenses/publicdomain
+ */
+
+package java.util.concurrent.atomic;
+import sun.misc.Unsafe;
+
+/**
+ * A <tt>boolean</tt> value that may be updated atomically. See the
+ * {@link java.util.concurrent.atomic} package specification for
+ * description of the properties of atomic variables. An
+ * <tt>AtomicBoolean</tt> is used in applications such as atomically
+ * updated flags, and cannot be used as a replacement for a
+ * {@link java.lang.Boolean}.
+ *
+ * @since 1.5
+ * @author Doug Lea
+ */
+public class AtomicBoolean implements java.io.Serializable {
+    private static final long serialVersionUID = 4654671469794556979L;
+    // setup to use Unsafe.compareAndSwapInt for updates
+    private static final Unsafe unsafe = Unsafe.getUnsafe();
+    private static final long valueOffset;
+
+    static {
+      try {
+        valueOffset = unsafe.objectFieldOffset
+            (AtomicBoolean.class.getDeclaredField("value"));
+      } catch (Exception ex) { throw new Error(ex); }
+    }
+
+    private volatile int value;
+
+    /**
+     * Creates a new <tt>AtomicBoolean</tt> with the given initial value.
+     *
+     * @param initialValue the initial value
+     */
+    public AtomicBoolean(boolean initialValue) {
+        value = initialValue ? 1 : 0;
+    }
+
+    /**
+     * Creates a new <tt>AtomicBoolean</tt> with initial value <tt>false</tt>.
+     */
+    public AtomicBoolean() {
+    }
+
+    /**
+     * Returns the current value.
+     *
+     * @return the current value
+     */
+    public final boolean get() {
+        return value != 0;
+    }
+
+    /**
+     * Atomically sets the value to the given updated value
+     * if the current value <tt>==</tt> the expected value.
+     *
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful. False return indicates that
+     * the actual value was not equal to the expected value.
+     */
+    public final boolean compareAndSet(boolean expect, boolean update) {
+        int e = expect ? 1 : 0;
+        int u = update ? 1 : 0;
+        return unsafe.compareAndSwapInt(this, valueOffset, e, u);
+    }
+
+    /**
+     * Atomically sets the value to the given updated value
+     * if the current value <tt>==</tt> the expected value.
+     * May fail spuriously and does not provide ordering guarantees,
+     * so is only rarely an appropriate alternative to <tt>compareAndSet</tt>.
+     *
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful.
+     */
+    public boolean weakCompareAndSet(boolean expect, boolean update) {
+        int e = expect ? 1 : 0;
+        int u = update ? 1 : 0;
+        return unsafe.compareAndSwapInt(this, valueOffset, e, u);
+    }
+
+    /**
+     * Unconditionally sets to the given value.
+     *
+     * @param newValue the new value
+     */
+    public final void set(boolean newValue) {
+        value = newValue ? 1 : 0;
+    }
+
+    /**
+     * Eventually sets to the given value.
+     *
+     * @param newValue the new value
+     * @since 1.6
+     */
+    public final void lazySet(boolean newValue) {
+        int v = newValue ? 1 : 0;
+        unsafe.putOrderedInt(this, valueOffset, v);
+    }
+
+    /**
+     * Atomically sets to the given value and returns the previous value.
+     *
+     * @param newValue the new value
+     * @return the previous value
+     */
+    public final boolean getAndSet(boolean newValue) {
+        for (;;) {
+            boolean current = get();
+            if (compareAndSet(current, newValue))
+                return current;
+        }
+    }
+
+    /**
+     * Returns the String representation of the current value.
+     * @return the String representation of the current value.
+     */
+    public String toString() {
+        return Boolean.toString(get());
+    }
+
+}
diff --git a/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicInteger.java b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicInteger.java
new file mode 100644
index 000000000..0f723f613
--- /dev/null
+++ b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicInteger.java
@@ -0,0 +1,234 @@
+/*
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/licenses/publicdomain
+ */
+
+package java.util.concurrent.atomic;
+import sun.misc.Unsafe;
+
+/**
+ * An <tt>int</tt> value that may be updated atomically.  See the
+ * {@link java.util.concurrent.atomic} package specification for
+ * description of the properties of atomic variables. An
+ * <tt>AtomicInteger</tt> is used in applications such as atomically
+ * incremented counters, and cannot be used as a replacement for an
+ * {@link java.lang.Integer}. However, this class does extend
+ * <tt>Number</tt> to allow uniform access by tools and utilities that
+ * deal with numerically-based classes.
+ *
+ * @since 1.5
+ * @author Doug Lea
+*/
+public class AtomicInteger extends Number implements java.io.Serializable {
+    private static final long serialVersionUID = 6214790243416807050L;
+
+    // setup to use Unsafe.compareAndSwapInt for updates
+    private static final Unsafe unsafe = Unsafe.getUnsafe();
+    private static final long valueOffset;
+
+    static {
+      try {
+        valueOffset = unsafe.objectFieldOffset
+            (AtomicInteger.class.getDeclaredField("value"));
+      } catch (Exception ex) { throw new Error(ex); }
+    }
+
+    private volatile int value;
+
+    /**
+     * Creates a new AtomicInteger with the given initial value.
+     *
+     * @param initialValue the initial value
+     */
+    public AtomicInteger(int initialValue) {
+        value = initialValue;
+    }
+
+    /**
+     * Creates a new AtomicInteger with initial value <tt>0</tt>.
+     */
+    public AtomicInteger() {
+    }
+
+    /**
+     * Gets the current value.
+     *
+     * @return the current value
+     */
+    public final int get() {
+        return value;
+    }
+
+    /**
+     * Sets to the given value.
+     *
+     * @param newValue the new value
+     */
+    public final void set(int newValue) {
+        value = newValue;
+    }
+
+    /**
+     * Eventually sets to the given value.
+     *
+     * @param newValue the new value
+     * @since 1.6
+     */
+    public final void lazySet(int newValue) {
+        unsafe.putOrderedInt(this, valueOffset, newValue);
+    }
+
+    /**
+     * Atomically sets to the given value and returns the old value.
+     *
+     * @param newValue the new value
+     * @return the previous value
+     */
+    public final int getAndSet(int newValue) {
+        for (;;) {
+            int current = get();
+            if (compareAndSet(current, newValue))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically sets the value to the given updated value
+     * if the current value <tt>==</tt> the expected value.
+     *
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful. False return indicates that
+     * the actual value was not equal to the expected value.
+     */
+    public final boolean compareAndSet(int expect, int update) {
+        return unsafe.compareAndSwapInt(this, valueOffset, expect, update);
+    }
+
+    /**
+     * Atomically sets the value to the given updated value
+     * if the current value <tt>==</tt> the expected value.
+     * May fail spuriously and does not provide ordering guarantees,
+     * so is only rarely an appropriate alternative to <tt>compareAndSet</tt>.
+     *
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful.
+     */
+    public final boolean weakCompareAndSet(int expect, int update) {
+        return unsafe.compareAndSwapInt(this, valueOffset, expect, update);
+    }
+
+    /**
+     * Atomically increments by one the current value.
+     *
+     * @return the previous value
+     */
+    public final int getAndIncrement() {
+        for (;;) {
+            int current = get();
+            int next = current + 1;
+            if (compareAndSet(current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically decrements by one the current value.
+     *
+     * @return the previous value
+     */
+    public final int getAndDecrement() {
+        for (;;) {
+            int current = get();
+            int next = current - 1;
+            if (compareAndSet(current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically adds the given value to the current value.
+     *
+     * @param delta the value to add
+     * @return the previous value
+     */
+    public final int getAndAdd(int delta) {
+        for (;;) {
+            int current = get();
+            int next = current + delta;
+            if (compareAndSet(current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically increments by one the current value.
+     *
+     * @return the updated value
+     */
+    public final int incrementAndGet() {
+        for (;;) {
+            int current = get();
+            int next = current + 1;
+            if (compareAndSet(current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Atomically decrements by one the current value.
+     *
+     * @return the updated value
+     */
+    public final int decrementAndGet() {
+        for (;;) {
+            int current = get();
+            int next = current - 1;
+            if (compareAndSet(current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Atomically adds the given value to the current value.
+     *
+     * @param delta the value to add
+     * @return the updated value
+     */
+    public final int addAndGet(int delta) {
+        for (;;) {
+            int current = get();
+            int next = current + delta;
+            if (compareAndSet(current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Returns the String representation of the current value.
+     * @return the String representation of the current value.
+     */
+    public String toString() {
+        return Integer.toString(get());
+    }
+
+
+    public int intValue() {
+        return get();
+    }
+
+    public long longValue() {
+        return (long)get();
+    }
+
+    public float floatValue() {
+        return (float)get();
+    }
+
+    public double doubleValue() {
+        return (double)get();
+    }
+
+}
diff --git a/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicIntegerArray.java b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicIntegerArray.java
new file mode 100644
index 000000000..2ad754fda
--- /dev/null
+++ b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicIntegerArray.java
@@ -0,0 +1,255 @@
+/*
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/licenses/publicdomain
+ */
+
+package java.util.concurrent.atomic;
+import sun.misc.Unsafe;
+import java.util.*;
+
+/**
+ * An <tt>int</tt> 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.
+ * @since 1.5
+ * @author Doug Lea
+ */
+public class AtomicIntegerArray implements java.io.Serializable {
+    private static final long serialVersionUID = 2862133569453604235L;
+
+   // setup to use Unsafe.compareAndSwapInt for updates
+    private static final Unsafe unsafe = Unsafe.getUnsafe();
+    private static final int base = unsafe.arrayBaseOffset(int[].class);
+    private static final int scale = unsafe.arrayIndexScale(int[].class);
+    private final int[] array;
+
+    private long rawIndex(int i) {
+        if (i < 0 || i >= array.length)
+            throw new IndexOutOfBoundsException("index " + i);
+        return base + i * scale;
+    }
+
+    /**
+     * Creates a new AtomicIntegerArray of given length.
+     *
+     * @param length the length of the array
+     */
+    public AtomicIntegerArray(int length) {
+        array = new int[length];
+        // must perform at least one volatile write to conform to JMM
+        if (length > 0)
+            unsafe.putIntVolatile(array, rawIndex(0), 0);
+    }
+
+    /**
+     * Creates a new AtomicIntegerArray with the same length as, and
+     * all elements copied from, the given array.
+     *
+     * @param array the array to copy elements from
+     * @throws NullPointerException if array is null
+     */
+    public AtomicIntegerArray(int[] array) {
+        if (array == null)
+            throw new NullPointerException();
+        int length = array.length;
+        this.array = new int[length];
+        if (length > 0) {
+            int last = length-1;
+            for (int i = 0; i < last; ++i)
+                this.array[i] = array[i];
+            // Do the last write as volatile
+            unsafe.putIntVolatile(this.array, rawIndex(last), array[last]);
+        }
+    }
+
+    /**
+     * Returns the length of the array.
+     *
+     * @return the length of the array
+     */
+    public final int length() {
+        return array.length;
+    }
+
+    /**
+     * Gets the current value at position <tt>i</tt>.
+     *
+     * @param i the index
+     * @return the current value
+     */
+    public final int get(int i) {
+        return unsafe.getIntVolatile(array, rawIndex(i));
+    }
+
+    /**
+     * Sets the element at position <tt>i</tt> to the given value.
+     *
+     * @param i the index
+     * @param newValue the new value
+     */
+    public final void set(int i, int newValue) {
+        unsafe.putIntVolatile(array, rawIndex(i), newValue);
+    }
+
+    /**
+     * Eventually sets the element at position <tt>i</tt> to the given value.
+     *
+     * @param i the index
+     * @param newValue the new value
+     * @since 1.6
+     */
+    public final void lazySet(int i, int newValue) {
+        unsafe.putOrderedInt(array, rawIndex(i), newValue);
+    }
+
+    /**
+     * Atomically sets the element at position <tt>i</tt> to the given
+     * value and returns the old value.
+     *
+     * @param i the index
+     * @param newValue the new value
+     * @return the previous value
+     */
+    public final int getAndSet(int i, int newValue) {
+        while (true) {
+            int current = get(i);
+            if (compareAndSet(i, current, newValue))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically sets the element at position <tt>i</tt> to the given
+     * updated value if the current value <tt>==</tt> the expected value.
+     *
+     * @param i the index
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful. False return indicates that
+     * the actual value was not equal to the expected value.
+     */
+    public final boolean compareAndSet(int i, int expect, int update) {
+        return unsafe.compareAndSwapInt(array, rawIndex(i),
+                                        expect, update);
+    }
+
+    /**
+     * Atomically sets the element at position <tt>i</tt> to the given
+     * updated value if the current value <tt>==</tt> the expected value.
+     * May fail spuriously and does not provide ordering guarantees,
+     * so is only rarely an appropriate alternative to <tt>compareAndSet</tt>.
+     *
+     * @param i the index
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful.
+     */
+    public final boolean weakCompareAndSet(int i, int expect, int update) {
+        return compareAndSet(i, expect, update);
+    }
+
+    /**
+     * Atomically increments by one the element at index <tt>i</tt>.
+     *
+     * @param i the index
+     * @return the previous value
+     */
+    public final int getAndIncrement(int i) {
+        while (true) {
+            int current = get(i);
+            int next = current + 1;
+            if (compareAndSet(i, current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically decrements by one the element at index <tt>i</tt>.
+     *
+     * @param i the index
+     * @return the previous value
+     */
+    public final int getAndDecrement(int i) {
+        while (true) {
+            int current = get(i);
+            int next = current - 1;
+            if (compareAndSet(i, current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically adds the given value to the element at index <tt>i</tt>.
+     *
+     * @param i the index
+     * @param delta the value to add
+     * @return the previous value
+     */
+    public final int getAndAdd(int i, int delta) {
+        while (true) {
+            int current = get(i);
+            int next = current + delta;
+            if (compareAndSet(i, current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically increments by one the element at index <tt>i</tt>.
+     *
+     * @param i the index
+     * @return the updated value
+     */
+    public final int incrementAndGet(int i) {
+        while (true) {
+            int current = get(i);
+            int next = current + 1;
+            if (compareAndSet(i, current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Atomically decrements by one the element at index <tt>i</tt>.
+     *
+     * @param i the index
+     * @return the updated value
+     */
+    public final int decrementAndGet(int i) {
+        while (true) {
+            int current = get(i);
+            int next = current - 1;
+            if (compareAndSet(i, current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Atomically adds the given value to the element at index <tt>i</tt>.
+     *
+     * @param i the index
+     * @param delta the value to add
+     * @return the updated value
+     */
+    public final int addAndGet(int i, int delta) {
+        while (true) {
+            int current = get(i);
+            int next = current + delta;
+            if (compareAndSet(i, current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Returns the String representation of the current values of array.
+     * @return the String representation of the current values of array.
+     */
+    public String toString() {
+        if (array.length > 0) // force volatile read
+            get(0);
+        return Arrays.toString(array);
+    }
+
+}
diff --git a/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicIntegerFieldUpdater.java b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicIntegerFieldUpdater.java
new file mode 100644
index 000000000..c957bbf3f
--- /dev/null
+++ b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicIntegerFieldUpdater.java
@@ -0,0 +1,316 @@
+/*
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/licenses/publicdomain
+ */
+
+package java.util.concurrent.atomic;
+import sun.misc.Unsafe;
+import java.lang.reflect.*;
+
+/**
+ * A reflection-based utility that enables atomic updates to
+ * designated <tt>volatile int</tt> fields of designated classes.
+ * This class is designed for use in atomic data structures in which
+ * several fields of the same node are independently subject to atomic
+ * updates.
+ *
+ * <p>Note that the guarantees of the {@code compareAndSet}
+ * method in this class are weaker than in other atomic classes.
+ * Because this class cannot ensure that all uses of the field
+ * are appropriate for purposes of atomic access, it can
+ * guarantee atomicity only with respect to other invocations of
+ * {@code compareAndSet} and {@code set} on the same updater.
+ *
+ * @since 1.5
+ * @author Doug Lea
+ * @param <T> The type of the object holding the updatable field
+ */
+public abstract class  AtomicIntegerFieldUpdater<T>  {
+    /**
+     * Creates and returns an updater for objects with the given field.
+     * The Class argument is needed to check that reflective types and
+     * generic types match.
+     *
+     * @param tclass the class of the objects holding the field
+     * @param fieldName the name of the field to be updated
+     * @return the updater
+     * @throws IllegalArgumentException if the field is not a
+     * volatile integer type
+     * @throws RuntimeException with a nested reflection-based
+     * exception if the class does not hold field or is the wrong type
+     */
+    public static <U> AtomicIntegerFieldUpdater<U> newUpdater(Class<U> tclass, String fieldName) {
+        return new AtomicIntegerFieldUpdaterImpl<U>(tclass, fieldName);
+    }
+
+    /**
+     * Protected do-nothing constructor for use by subclasses.
+     */
+    protected AtomicIntegerFieldUpdater() {
+    }
+
+    /**
+     * Atomically sets the field of the given object managed by this updater
+     * to the given updated value if the current value <tt>==</tt> the
+     * expected value. This method is guaranteed to be atomic with respect to
+     * other calls to <tt>compareAndSet</tt> and <tt>set</tt>, but not
+     * necessarily with respect to other changes in the field.
+     *
+     * @param obj An object whose field to conditionally set
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful
+     * @throws ClassCastException if <tt>obj</tt> is not an instance
+     * of the class possessing the field established in the constructor
+     */
+    public abstract boolean compareAndSet(T obj, int expect, int update);
+
+    /**
+     * Atomically sets the field of the given object managed by this updater
+     * to the given updated value if the current value <tt>==</tt> the
+     * expected value. This method is guaranteed to be atomic with respect to
+     * other calls to <tt>compareAndSet</tt> and <tt>set</tt>, but not
+     * necessarily with respect to other changes in the field.
+     * May fail spuriously and does not provide ordering guarantees,
+     * so is only rarely an appropriate alternative to <tt>compareAndSet</tt>.
+     *
+     * @param obj An object whose field to conditionally set
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful
+     * @throws ClassCastException if <tt>obj</tt> is not an instance
+     * of the class possessing the field established in the constructor
+     */
+    public abstract boolean weakCompareAndSet(T obj, int expect, int update);
+
+    /**
+     * Sets the field of the given object managed by this updater to the
+     * given updated value. This operation is guaranteed to act as a volatile
+     * store with respect to subsequent invocations of
+     * <tt>compareAndSet</tt>.
+     *
+     * @param obj An object whose field to set
+     * @param newValue the new value
+     */
+    public abstract void set(T obj, int newValue);
+
+    /**
+     * Eventually sets the field of the given object managed by this
+     * updater to the given updated value.
+     *
+     * @param obj An object whose field to set
+     * @param newValue the new value
+     * @since 1.6
+     */
+    public abstract void lazySet(T obj, int newValue);
+
+
+    /**
+     * Gets the current value held in the field of the given object managed
+     * by this updater.
+     *
+     * @param obj An object whose field to get
+     * @return the current value
+     */
+    public abstract int get(T obj);
+
+    /**
+     * Atomically sets the field of the given object managed by this updater
+     * to the given value and returns the old value.
+     *
+     * @param obj An object whose field to get and set
+     * @param newValue the new value
+     * @return the previous value
+     */
+    public int getAndSet(T obj, int newValue) {
+        for (;;) {
+            int current = get(obj);
+            if (compareAndSet(obj, current, newValue))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically increments by one the current value of the field of the
+     * given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @return the previous value
+     */
+    public int getAndIncrement(T obj) {
+        for (;;) {
+            int current = get(obj);
+            int next = current + 1;
+            if (compareAndSet(obj, current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically decrements by one the current value of the field of the
+     * given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @return the previous value
+     */
+    public int getAndDecrement(T obj) {
+        for (;;) {
+            int current = get(obj);
+            int next = current - 1;
+            if (compareAndSet(obj, current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically adds the given value to the current value of the field of
+     * the given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @param delta the value to add
+     * @return the previous value
+     */
+    public int getAndAdd(T obj, int delta) {
+        for (;;) {
+            int current = get(obj);
+            int next = current + delta;
+            if (compareAndSet(obj, current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically increments by one the current value of the field of the
+     * given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @return the updated value
+     */
+    public int incrementAndGet(T obj) {
+        for (;;) {
+            int current = get(obj);
+            int next = current + 1;
+            if (compareAndSet(obj, current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Atomically decrements by one the current value of the field of the
+     * given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @return the updated value
+     */
+    public int decrementAndGet(T obj) {
+        for (;;) {
+            int current = get(obj);
+            int next = current - 1;
+            if (compareAndSet(obj, current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Atomically adds the given value to the current value of the field of
+     * the given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @param delta the value to add
+     * @return the updated value
+     */
+    public int addAndGet(T obj, int delta) {
+        for (;;) {
+            int current = get(obj);
+            int next = current + delta;
+            if (compareAndSet(obj, current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Standard hotspot implementation using intrinsics
+     */
+    private static class AtomicIntegerFieldUpdaterImpl<T> extends AtomicIntegerFieldUpdater<T> {
+        private static final Unsafe unsafe = Unsafe.getUnsafe();
+        private final long offset;
+        private final Class<T> tclass;
+        private final Class cclass;
+
+        AtomicIntegerFieldUpdaterImpl(Class<T> tclass, String fieldName) {
+            Field field = null;
+            Class caller = null;
+            int modifiers = 0;
+            try {
+                field = tclass.getDeclaredField(fieldName);
+                caller = sun.reflect.Reflection.getCallerClass(3);
+                modifiers = field.getModifiers();
+                sun.reflect.misc.ReflectUtil.ensureMemberAccess(
+                    caller, tclass, null, modifiers);
+                sun.reflect.misc.ReflectUtil.checkPackageAccess(tclass);
+            } catch(Exception ex) {
+                throw new RuntimeException(ex);
+            }
+
+            Class fieldt = field.getType();
+            if (fieldt != int.class)
+                throw new IllegalArgumentException("Must be integer type");
+
+            if (!Modifier.isVolatile(modifiers))
+                throw new IllegalArgumentException("Must be volatile type");
+
+            this.cclass = (Modifier.isProtected(modifiers) &&
+                           caller != tclass) ? caller : null;
+            this.tclass = tclass;
+            offset = unsafe.objectFieldOffset(field);
+        }
+
+        private void fullCheck(T obj) {
+            if (!tclass.isInstance(obj))
+                throw new ClassCastException();
+            if (cclass != null)
+                ensureProtectedAccess(obj);
+        }
+
+        public boolean compareAndSet(T obj, int expect, int update) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            return unsafe.compareAndSwapInt(obj, offset, expect, update);
+        }
+
+        public boolean weakCompareAndSet(T obj, int expect, int update) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            return unsafe.compareAndSwapInt(obj, offset, expect, update);
+        }
+
+        public void set(T obj, int newValue) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            unsafe.putIntVolatile(obj, offset, newValue);
+        }
+
+        public void lazySet(T obj, int newValue) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            unsafe.putOrderedInt(obj, offset, newValue);
+        }
+
+        public final int get(T obj) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            return unsafe.getIntVolatile(obj, offset);
+        }
+
+        private void ensureProtectedAccess(T obj) {
+            if (cclass.isInstance(obj)) {
+                return;
+            }
+            throw new RuntimeException(
+                new IllegalAccessException("Class " +
+                    cclass.getName() +
+                    " can not access a protected member of class " +
+                    tclass.getName() +
+                    " using an instance of " +
+                    obj.getClass().getName()
+                )
+            );
+        }
+    }
+}
diff --git a/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicLong.java b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicLong.java
new file mode 100644
index 000000000..fa254ba62
--- /dev/null
+++ b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicLong.java
@@ -0,0 +1,248 @@
+/*
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/licenses/publicdomain
+ */
+
+package java.util.concurrent.atomic;
+import sun.misc.Unsafe;
+
+/**
+ * A <tt>long</tt> value that may be updated atomically.  See the
+ * {@link java.util.concurrent.atomic} package specification for
+ * description of the properties of atomic variables. An
+ * <tt>AtomicLong</tt> is used in applications such as atomically
+ * incremented sequence numbers, and cannot be used as a replacement
+ * for a {@link java.lang.Long}. However, this class does extend
+ * <tt>Number</tt> to allow uniform access by tools and utilities that
+ * deal with numerically-based classes.
+ *
+ * @since 1.5
+ * @author Doug Lea
+ */
+public class AtomicLong extends Number implements java.io.Serializable {
+    private static final long serialVersionUID = 1927816293512124184L;
+
+    // setup to use Unsafe.compareAndSwapLong for updates
+    private static final Unsafe unsafe = Unsafe.getUnsafe();
+    private static final long valueOffset;
+
+    /**
+     * Records whether the underlying JVM supports lockless
+     * CompareAndSet for longs. While the unsafe.CompareAndSetLong
+     * method works in either case, some constructions should be
+     * handled at Java level to avoid locking user-visible locks.
+     */
+    static final boolean VM_SUPPORTS_LONG_CAS = VMSupportsCS8();
+
+    /**
+     * Returns whether underlying JVM supports lockless CompareAndSet
+     * for longs. Called only once and cached in VM_SUPPORTS_LONG_CAS.
+     */
+    private static native boolean VMSupportsCS8();
+
+    static {
+      try {
+        valueOffset = unsafe.objectFieldOffset
+            (AtomicLong.class.getDeclaredField("value"));
+      } catch (Exception ex) { throw new Error(ex); }
+    }
+
+    private volatile long value;
+
+    /**
+     * Creates a new AtomicLong with the given initial value.
+     *
+     * @param initialValue the initial value
+     */
+    public AtomicLong(long initialValue) {
+        value = initialValue;
+    }
+
+    /**
+     * Creates a new AtomicLong with initial value <tt>0</tt>.
+     */
+    public AtomicLong() {
+    }
+
+    /**
+     * Gets the current value.
+     *
+     * @return the current value
+     */
+    public final long get() {
+        return value;
+    }
+
+    /**
+     * Sets to the given value.
+     *
+     * @param newValue the new value
+     */
+    public final void set(long newValue) {
+        value = newValue;
+    }
+
+    /**
+     * Eventually sets to the given value.
+     *
+     * @param newValue the new value
+     * @since 1.6
+     */
+    public final void lazySet(long newValue) {
+        unsafe.putOrderedLong(this, valueOffset, newValue);
+    }
+
+    /**
+     * Atomically sets to the given value and returns the old value.
+     *
+     * @param newValue the new value
+     * @return the previous value
+     */
+    public final long getAndSet(long newValue) {
+        while (true) {
+            long current = get();
+            if (compareAndSet(current, newValue))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically sets the value to the given updated value
+     * if the current value <tt>==</tt> the expected value.
+     *
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful. False return indicates that
+     * the actual value was not equal to the expected value.
+     */
+    public final boolean compareAndSet(long expect, long update) {
+        return unsafe.compareAndSwapLong(this, valueOffset, expect, update);
+    }
+
+    /**
+     * Atomically sets the value to the given updated value
+     * if the current value <tt>==</tt> the expected value.
+     * May fail spuriously and does not provide ordering guarantees,
+     * so is only rarely an appropriate alternative to <tt>compareAndSet</tt>.
+     *
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful.
+     */
+    public final boolean weakCompareAndSet(long expect, long update) {
+        return unsafe.compareAndSwapLong(this, valueOffset, expect, update);
+    }
+
+    /**
+     * Atomically increments by one the current value.
+     *
+     * @return the previous value
+     */
+    public final long getAndIncrement() {
+        while (true) {
+            long current = get();
+            long next = current + 1;
+            if (compareAndSet(current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically decrements by one the current value.
+     *
+     * @return the previous value
+     */
+    public final long getAndDecrement() {
+        while (true) {
+            long current = get();
+            long next = current - 1;
+            if (compareAndSet(current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically adds the given value to the current value.
+     *
+     * @param delta the value to add
+     * @return the previous value
+     */
+    public final long getAndAdd(long delta) {
+        while (true) {
+            long current = get();
+            long next = current + delta;
+            if (compareAndSet(current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically increments by one the current value.
+     *
+     * @return the updated value
+     */
+    public final long incrementAndGet() {
+        for (;;) {
+            long current = get();
+            long next = current + 1;
+            if (compareAndSet(current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Atomically decrements by one the current value.
+     *
+     * @return the updated value
+     */
+    public final long decrementAndGet() {
+        for (;;) {
+            long current = get();
+            long next = current - 1;
+            if (compareAndSet(current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Atomically adds the given value to the current value.
+     *
+     * @param delta the value to add
+     * @return the updated value
+     */
+    public final long addAndGet(long delta) {
+        for (;;) {
+            long current = get();
+            long next = current + delta;
+            if (compareAndSet(current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Returns the String representation of the current value.
+     * @return the String representation of the current value.
+     */
+    public String toString() {
+        return Long.toString(get());
+    }
+
+
+    public int intValue() {
+        return (int)get();
+    }
+
+    public long longValue() {
+        return (long)get();
+    }
+
+    public float floatValue() {
+        return (float)get();
+    }
+
+    public double doubleValue() {
+        return (double)get();
+    }
+
+}
diff --git a/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicLongArray.java b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicLongArray.java
new file mode 100644
index 000000000..c582cba54
--- /dev/null
+++ b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicLongArray.java
@@ -0,0 +1,255 @@
+/*
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/licenses/publicdomain
+ */
+
+package java.util.concurrent.atomic;
+import sun.misc.Unsafe;
+import java.util.*;
+
+/**
+ * A <tt>long</tt> 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.
+ * @since 1.5
+ * @author Doug Lea
+ */
+public class AtomicLongArray implements java.io.Serializable {
+    private static final long serialVersionUID = -2308431214976778248L;
+
+    // setup to use Unsafe.compareAndSwapInt for updates
+    private static final Unsafe unsafe = Unsafe.getUnsafe();
+    private static final int base = unsafe.arrayBaseOffset(long[].class);
+    private static final int scale = unsafe.arrayIndexScale(long[].class);
+    private final long[] array;
+
+    private long rawIndex(int i) {
+        if (i < 0 || i >= array.length)
+            throw new IndexOutOfBoundsException("index " + i);
+        return base + i * scale;
+    }
+
+    /**
+     * Creates a new AtomicLongArray of given length.
+     *
+     * @param length the length of the array
+     */
+    public AtomicLongArray(int length) {
+        array = new long[length];
+        // must perform at least one volatile write to conform to JMM
+        if (length > 0)
+            unsafe.putLongVolatile(array, rawIndex(0), 0);
+    }
+
+    /**
+     * Creates a new AtomicLongArray with the same length as, and
+     * all elements copied from, the given array.
+     *
+     * @param array the array to copy elements from
+     * @throws NullPointerException if array is null
+     */
+    public AtomicLongArray(long[] array) {
+        if (array == null)
+            throw new NullPointerException();
+        int length = array.length;
+        this.array = new long[length];
+        if (length > 0) {
+            int last = length-1;
+            for (int i = 0; i < last; ++i)
+                this.array[i] = array[i];
+            // Do the last write as volatile
+            unsafe.putLongVolatile(this.array, rawIndex(last), array[last]);
+        }
+    }
+
+    /**
+     * Returns the length of the array.
+     *
+     * @return the length of the array
+     */
+    public final int length() {
+        return array.length;
+    }
+
+    /**
+     * Gets the current value at position <tt>i</tt>.
+     *
+     * @param i the index
+     * @return the current value
+     */
+    public final long get(int i) {
+        return unsafe.getLongVolatile(array, rawIndex(i));
+    }
+
+    /**
+     * Sets the element at position <tt>i</tt> to the given value.
+     *
+     * @param i the index
+     * @param newValue the new value
+     */
+    public final void set(int i, long newValue) {
+        unsafe.putLongVolatile(array, rawIndex(i), newValue);
+    }
+
+    /**
+     * Eventually sets the element at position <tt>i</tt> to the given value.
+     *
+     * @param i the index
+     * @param newValue the new value
+     * @since 1.6
+     */
+    public final void lazySet(int i, long newValue) {
+        unsafe.putOrderedLong(array, rawIndex(i), newValue);
+    }
+
+
+    /**
+     * Atomically sets the element at position <tt>i</tt> to the given value
+     * and returns the old value.
+     *
+     * @param i the index
+     * @param newValue the new value
+     * @return the previous value
+     */
+    public final long getAndSet(int i, long newValue) {
+        while (true) {
+            long current = get(i);
+            if (compareAndSet(i, current, newValue))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically sets the value to the given updated value
+     * if the current value <tt>==</tt> the expected value.
+     *
+     * @param i the index
+     * @param expect the expected value
+     * @param update the new value
+     * @return 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 unsafe.compareAndSwapLong(array, rawIndex(i),
+                                         expect, update);
+    }
+
+    /**
+     * Atomically sets the value to the given updated value
+     * if the current value <tt>==</tt> the expected value.
+     * May fail spuriously and does not provide ordering guarantees,
+     * so is only rarely an appropriate alternative to <tt>compareAndSet</tt>.
+     *
+     * @param i the index
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful.
+     */
+    public final boolean weakCompareAndSet(int i, long expect, long update) {
+        return compareAndSet(i, expect, update);
+    }
+
+    /**
+     * Atomically increments by one the element at index <tt>i</tt>.
+     *
+     * @param i the index
+     * @return the previous value
+     */
+    public final long getAndIncrement(int i) {
+        while (true) {
+            long current = get(i);
+            long next = current + 1;
+            if (compareAndSet(i, current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically decrements by one the element at index <tt>i</tt>.
+     *
+     * @param i the index
+     * @return the previous value
+     */
+    public final long getAndDecrement(int i) {
+        while (true) {
+            long current = get(i);
+            long next = current - 1;
+            if (compareAndSet(i, current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically adds the given value to the element at index <tt>i</tt>.
+     *
+     * @param i the index
+     * @param delta the value to add
+     * @return the previous value
+     */
+    public final long getAndAdd(int i, long delta) {
+        while (true) {
+            long current = get(i);
+            long next = current + delta;
+            if (compareAndSet(i, current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically increments by one the element at index <tt>i</tt>.
+     *
+     * @param i the index
+     * @return the updated value
+     */
+    public final long incrementAndGet(int i) {
+        while (true) {
+            long current = get(i);
+            long next = current + 1;
+            if (compareAndSet(i, current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Atomically decrements by one the element at index <tt>i</tt>.
+     *
+     * @param i the index
+     * @return the updated value
+     */
+    public final long decrementAndGet(int i) {
+        while (true) {
+            long current = get(i);
+            long next = current - 1;
+            if (compareAndSet(i, current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Atomically adds the given value to the element at index <tt>i</tt>.
+     *
+     * @param i the index
+     * @param delta the value to add
+     * @return the updated value
+     */
+    public long addAndGet(int i, long delta) {
+        while (true) {
+            long current = get(i);
+            long next = current + delta;
+            if (compareAndSet(i, current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Returns the String representation of the current values of array.
+     * @return the String representation of the current values of array.
+     */
+    public String toString() {
+        if (array.length > 0) // force volatile read
+            get(0);
+        return Arrays.toString(array);
+    }
+
+}
diff --git a/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicLongFieldUpdater.java b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicLongFieldUpdater.java
new file mode 100644
index 000000000..f6135d1fc
--- /dev/null
+++ b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicLongFieldUpdater.java
@@ -0,0 +1,406 @@
+/*
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/licenses/publicdomain
+ */
+
+package java.util.concurrent.atomic;
+import sun.misc.Unsafe;
+import java.lang.reflect.*;
+
+/**
+ * A reflection-based utility that enables atomic updates to
+ * designated <tt>volatile long</tt> fields of designated classes.
+ * This class is designed for use in atomic data structures in which
+ * several fields of the same node are independently subject to atomic
+ * updates.
+ *
+ * <p>Note that the guarantees of the {@code compareAndSet}
+ * method in this class are weaker than in other atomic classes.
+ * Because this class cannot ensure that all uses of the field
+ * are appropriate for purposes of atomic access, it can
+ * guarantee atomicity only with respect to other invocations of
+ * {@code compareAndSet} and {@code set} on the same updater.
+ *
+ * @since 1.5
+ * @author Doug Lea
+ * @param <T> The type of the object holding the updatable field
+ */
+public abstract class  AtomicLongFieldUpdater<T>  {
+    /**
+     * Creates and returns an updater for objects with the given field.
+     * The Class argument is needed to check that reflective types and
+     * generic types match.
+     *
+     * @param tclass the class of the objects holding the field
+     * @param fieldName the name of the field to be updated.
+     * @return the updater
+     * @throws IllegalArgumentException if the field is not a
+     * volatile long type.
+     * @throws RuntimeException with a nested reflection-based
+     * exception if the class does not hold field or is the wrong type.
+     */
+    public static <U> AtomicLongFieldUpdater<U> newUpdater(Class<U> tclass, String fieldName) {
+        if (AtomicLong.VM_SUPPORTS_LONG_CAS)
+            return new CASUpdater<U>(tclass, fieldName);
+        else
+            return new LockedUpdater<U>(tclass, fieldName);
+    }
+
+    /**
+     * Protected do-nothing constructor for use by subclasses.
+     */
+    protected AtomicLongFieldUpdater() {
+    }
+
+    /**
+     * Atomically sets the field of the given object managed by this updater
+     * to the given updated value if the current value <tt>==</tt> the
+     * expected value. This method is guaranteed to be atomic with respect to
+     * other calls to <tt>compareAndSet</tt> and <tt>set</tt>, but not
+     * necessarily with respect to other changes in the field.
+     *
+     * @param obj An object whose field to conditionally set
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful.
+     * @throws ClassCastException if <tt>obj</tt> is not an instance
+     * of the class possessing the field established in the constructor.
+     */
+    public abstract boolean compareAndSet(T obj, long expect, long update);
+
+    /**
+     * Atomically sets the field of the given object managed by this updater
+     * to the given updated value if the current value <tt>==</tt> the
+     * expected value. This method is guaranteed to be atomic with respect to
+     * other calls to <tt>compareAndSet</tt> and <tt>set</tt>, but not
+     * necessarily with respect to other changes in the field.
+     * May fail spuriously and does not provide ordering guarantees,
+     * so is only rarely an appropriate alternative to <tt>compareAndSet</tt>.
+     *
+     * @param obj An object whose field to conditionally set
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful.
+     * @throws ClassCastException if <tt>obj</tt> is not an instance
+     * of the class possessing the field established in the constructor.
+     */
+    public abstract boolean weakCompareAndSet(T obj, long expect, long update);
+
+    /**
+     * Sets the field of the given object managed by this updater to the
+     * given updated value. This operation is guaranteed to act as a volatile
+     * store with respect to subsequent invocations of
+     * <tt>compareAndSet</tt>.
+     *
+     * @param obj An object whose field to set
+     * @param newValue the new value
+     */
+    public abstract void set(T obj, long newValue);
+
+    /**
+     * Eventually sets the field of the given object managed by this
+     * updater to the given updated value.
+     *
+     * @param obj An object whose field to set
+     * @param newValue the new value
+     * @since 1.6
+     */
+    public abstract void lazySet(T obj, long newValue);
+
+    /**
+     * Gets the current value held in the field of the given object managed
+     * by this updater.
+     *
+     * @param obj An object whose field to get
+     * @return the current value
+     */
+    public abstract long get(T obj);
+
+    /**
+     * Atomically sets the field of the given object managed by this updater
+     * to the given value and returns the old value.
+     *
+     * @param obj An object whose field to get and set
+     * @param newValue the new value
+     * @return the previous value
+     */
+    public long getAndSet(T obj, long newValue) {
+        for (;;) {
+            long current = get(obj);
+            if (compareAndSet(obj, current, newValue))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically increments by one the current value of the field of the
+     * given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @return the previous value
+     */
+    public long getAndIncrement(T obj) {
+        for (;;) {
+            long current = get(obj);
+            long next = current + 1;
+            if (compareAndSet(obj, current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically decrements by one the current value of the field of the
+     * given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @return the previous value
+     */
+    public long getAndDecrement(T obj) {
+        for (;;) {
+            long current = get(obj);
+            long next = current - 1;
+            if (compareAndSet(obj, current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically adds the given value to the current value of the field of
+     * the given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @param delta the value to add
+     * @return the previous value
+     */
+    public long getAndAdd(T obj, long delta) {
+        for (;;) {
+            long current = get(obj);
+            long next = current + delta;
+            if (compareAndSet(obj, current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically increments by one the current value of the field of the
+     * given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @return the updated value
+     */
+    public long incrementAndGet(T obj) {
+        for (;;) {
+            long current = get(obj);
+            long next = current + 1;
+            if (compareAndSet(obj, current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Atomically decrements by one the current value of the field of the
+     * given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @return the updated value
+     */
+    public long decrementAndGet(T obj) {
+        for (;;) {
+            long current = get(obj);
+            long next = current - 1;
+            if (compareAndSet(obj, current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Atomically adds the given value to the current value of the field of
+     * the given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @param delta the value to add
+     * @return the updated value
+     */
+    public long addAndGet(T obj, long delta) {
+        for (;;) {
+            long current = get(obj);
+            long next = current + delta;
+            if (compareAndSet(obj, current, next))
+                return next;
+        }
+    }
+
+    private static class CASUpdater<T> extends AtomicLongFieldUpdater<T> {
+        private static final Unsafe unsafe = Unsafe.getUnsafe();
+        private final long offset;
+        private final Class<T> tclass;
+        private final Class cclass;
+
+        CASUpdater(Class<T> tclass, String fieldName) {
+            Field field = null;
+            Class caller = null;
+            int modifiers = 0;
+            try {
+                field = tclass.getDeclaredField(fieldName);
+                caller = sun.reflect.Reflection.getCallerClass(3);
+                modifiers = field.getModifiers();
+                sun.reflect.misc.ReflectUtil.ensureMemberAccess(
+                    caller, tclass, null, modifiers);
+                sun.reflect.misc.ReflectUtil.checkPackageAccess(tclass);
+            } catch(Exception ex) {
+                throw new RuntimeException(ex);
+            }
+
+            Class fieldt = field.getType();
+            if (fieldt != long.class)
+                throw new IllegalArgumentException("Must be long type");
+
+            if (!Modifier.isVolatile(modifiers))
+                throw new IllegalArgumentException("Must be volatile type");
+
+            this.cclass = (Modifier.isProtected(modifiers) &&
+                           caller != tclass) ? caller : null;
+            this.tclass = tclass;
+            offset = unsafe.objectFieldOffset(field);
+        }
+
+        private void fullCheck(T obj) {
+            if (!tclass.isInstance(obj))
+                throw new ClassCastException();
+            if (cclass != null)
+                ensureProtectedAccess(obj);
+        }
+
+        public boolean compareAndSet(T obj, long expect, long update) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            return unsafe.compareAndSwapLong(obj, offset, expect, update);
+        }
+
+        public boolean weakCompareAndSet(T obj, long expect, long update) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            return unsafe.compareAndSwapLong(obj, offset, expect, update);
+        }
+
+        public void set(T obj, long newValue) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            unsafe.putLongVolatile(obj, offset, newValue);
+        }
+
+        public void lazySet(T obj, long newValue) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            unsafe.putOrderedLong(obj, offset, newValue);
+        }
+
+        public long get(T obj) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            return unsafe.getLongVolatile(obj, offset);
+        }
+
+        private void ensureProtectedAccess(T obj) {
+            if (cclass.isInstance(obj)) {
+                return;
+            }
+            throw new RuntimeException (
+                new IllegalAccessException("Class " +
+                    cclass.getName() +
+                    " can not access a protected member of class " +
+                    tclass.getName() +
+                    " using an instance of " +
+                    obj.getClass().getName()
+                )
+            );
+        }
+    }
+
+
+    private static class LockedUpdater<T> extends AtomicLongFieldUpdater<T> {
+        private static final Unsafe unsafe = Unsafe.getUnsafe();
+        private final long offset;
+        private final Class<T> tclass;
+        private final Class cclass;
+
+        LockedUpdater(Class<T> tclass, String fieldName) {
+            Field field = null;
+            Class caller = null;
+            int modifiers = 0;
+            try {
+                field = tclass.getDeclaredField(fieldName);
+                caller = sun.reflect.Reflection.getCallerClass(3);
+                modifiers = field.getModifiers();
+                sun.reflect.misc.ReflectUtil.ensureMemberAccess(
+                    caller, tclass, null, modifiers);
+                sun.reflect.misc.ReflectUtil.checkPackageAccess(tclass);
+            } catch(Exception ex) {
+                throw new RuntimeException(ex);
+            }
+
+            Class fieldt = field.getType();
+            if (fieldt != long.class)
+                throw new IllegalArgumentException("Must be long type");
+
+            if (!Modifier.isVolatile(modifiers))
+                throw new IllegalArgumentException("Must be volatile type");
+
+            this.cclass = (Modifier.isProtected(modifiers) &&
+                           caller != tclass) ? caller : null;
+            this.tclass = tclass;
+            offset = unsafe.objectFieldOffset(field);
+        }
+
+        private void fullCheck(T obj) {
+            if (!tclass.isInstance(obj))
+                throw new ClassCastException();
+            if (cclass != null)
+                ensureProtectedAccess(obj);
+        }
+
+        public boolean compareAndSet(T obj, long expect, long update) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            synchronized(this) {
+                long v = unsafe.getLong(obj, offset);
+                if (v != expect)
+                    return false;
+                unsafe.putLong(obj, offset, update);
+                return true;
+            }
+        }
+
+        public boolean weakCompareAndSet(T obj, long expect, long update) {
+            return compareAndSet(obj, expect, update);
+        }
+
+        public void set(T obj, long newValue) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            synchronized(this) {
+                unsafe.putLong(obj, offset, newValue);
+            }
+        }
+
+        public void lazySet(T obj, long newValue) {
+            set(obj, newValue);
+        }
+
+        public long get(T obj) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            synchronized(this) {
+                return unsafe.getLong(obj, offset);
+            }
+        }
+
+        private void ensureProtectedAccess(T obj) {
+            if (cclass.isInstance(obj)) {
+                return;
+            }
+            throw new RuntimeException (
+                new IllegalAccessException("Class " +
+                    cclass.getName() +
+                    " can not access a protected member of class " +
+                    tclass.getName() +
+                    " using an instance of " +
+                    obj.getClass().getName()
+                )
+            );
+        }
+    }
+}
diff --git a/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicMarkableReference.java b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicMarkableReference.java
new file mode 100644
index 000000000..85335b737
--- /dev/null
+++ b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicMarkableReference.java
@@ -0,0 +1,161 @@
+/*
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/licenses/publicdomain
+ */
+
+package java.util.concurrent.atomic;
+
+/**
+ * An <tt>AtomicMarkableReference</tt> maintains an object reference
+ * along with a mark bit, that can be updated atomically.
+ * <p>
+ * <p> Implementation note. This implementation maintains markable
+ * references by creating internal objects representing "boxed"
+ * [reference, boolean] pairs.
+ *
+ * @since 1.5
+ * @author Doug Lea
+ * @param <V> The type of object referred to by this reference
+ */
+public class AtomicMarkableReference<V>  {
+
+    private static class ReferenceBooleanPair<T> {
+        private final T reference;
+        private final boolean bit;
+        ReferenceBooleanPair(T r, boolean i) {
+            reference = r; bit = i;
+        }
+    }
+
+    private final AtomicReference<ReferenceBooleanPair<V>>  atomicRef;
+
+    /**
+     * Creates a new <tt>AtomicMarkableReference</tt> with the given
+     * initial values.
+     *
+     * @param initialRef the initial reference
+     * @param initialMark the initial mark
+     */
+    public AtomicMarkableReference(V initialRef, boolean initialMark) {
+        atomicRef = new AtomicReference<ReferenceBooleanPair<V>> (new ReferenceBooleanPair<V>(initialRef, initialMark));
+    }
+
+    /**
+     * Returns the current value of the reference.
+     *
+     * @return the current value of the reference
+     */
+    public V getReference() {
+        return atomicRef.get().reference;
+    }
+
+    /**
+     * Returns the current value of the mark.
+     *
+     * @return the current value of the mark
+     */
+    public boolean isMarked() {
+        return atomicRef.get().bit;
+    }
+
+    /**
+     * Returns the current values of both the reference and the mark.
+     * Typical usage is <tt>boolean[1] holder; ref = v.get(holder); </tt>.
+     *
+     * @param markHolder an array of size of at least one. On return,
+     * <tt>markholder[0]</tt> will hold the value of the mark.
+     * @return the current value of the reference
+     */
+    public V get(boolean[] markHolder) {
+        ReferenceBooleanPair<V> p = atomicRef.get();
+        markHolder[0] = p.bit;
+        return p.reference;
+    }
+
+    /**
+     * Atomically sets the value of both the reference and mark
+     * to the given update values if the
+     * current reference is <tt>==</tt> to the expected reference
+     * and the current mark is equal to the expected mark.
+     * May fail spuriously and does not provide ordering guarantees,
+     * so is only rarely an appropriate alternative to <tt>compareAndSet</tt>.
+     *
+     * @param expectedReference the expected value of the reference
+     * @param newReference the new value for the reference
+     * @param expectedMark the expected value of the mark
+     * @param newMark the new value for the mark
+     * @return true if successful
+     */
+    public boolean weakCompareAndSet(V       expectedReference,
+                                     V       newReference,
+                                     boolean expectedMark,
+                                     boolean newMark) {
+        ReferenceBooleanPair<V> current = atomicRef.get();
+        return  expectedReference == current.reference &&
+            expectedMark == current.bit &&
+            ((newReference == current.reference && newMark == current.bit) ||
+             atomicRef.weakCompareAndSet(current,
+                                     new ReferenceBooleanPair<V>(newReference,
+                                                              newMark)));
+    }
+
+    /**
+     * Atomically sets the value of both the reference and mark
+     * to the given update values if the
+     * current reference is <tt>==</tt> to the expected reference
+     * and the current mark is equal to the expected mark.
+     *
+     * @param expectedReference the expected value of the reference
+     * @param newReference the new value for the reference
+     * @param expectedMark the expected value of the mark
+     * @param newMark the new value for the mark
+     * @return true if successful
+     */
+    public boolean compareAndSet(V       expectedReference,
+                                 V       newReference,
+                                 boolean expectedMark,
+                                 boolean newMark) {
+        ReferenceBooleanPair<V> current = atomicRef.get();
+        return  expectedReference == current.reference &&
+            expectedMark == current.bit &&
+            ((newReference == current.reference && newMark == current.bit) ||
+             atomicRef.compareAndSet(current,
+                                     new ReferenceBooleanPair<V>(newReference,
+                                                              newMark)));
+    }
+
+    /**
+     * Unconditionally sets the value of both the reference and mark.
+     *
+     * @param newReference the new value for the reference
+     * @param newMark the new value for the mark
+     */
+    public void set(V newReference, boolean newMark) {
+        ReferenceBooleanPair<V> current = atomicRef.get();
+        if (newReference != current.reference || newMark != current.bit)
+            atomicRef.set(new ReferenceBooleanPair<V>(newReference, newMark));
+    }
+
+    /**
+     * Atomically sets the value of the mark to the given update value
+     * if the current reference is <tt>==</tt> to the expected
+     * reference.  Any given invocation of this operation may fail
+     * (return <tt>false</tt>) spuriously, but repeated invocation
+     * when the current value holds the expected value and no other
+     * thread is also attempting to set the value will eventually
+     * succeed.
+     *
+     * @param expectedReference the expected value of the reference
+     * @param newMark the new value for the mark
+     * @return true if successful
+     */
+    public boolean attemptMark(V expectedReference, boolean newMark) {
+        ReferenceBooleanPair<V> current = atomicRef.get();
+        return  expectedReference == current.reference &&
+            (newMark == current.bit ||
+             atomicRef.compareAndSet
+             (current, new ReferenceBooleanPair<V>(expectedReference,
+                                                newMark)));
+    }
+}
diff --git a/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicReference.java b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicReference.java
new file mode 100644
index 000000000..e7c989c2b
--- /dev/null
+++ b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicReference.java
@@ -0,0 +1,124 @@
+/*
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/licenses/publicdomain
+ */
+
+package java.util.concurrent.atomic;
+import sun.misc.Unsafe;
+
+/**
+ * An object reference that may be updated atomically. See the {@link
+ * java.util.concurrent.atomic} package specification for description
+ * of the properties of atomic variables.
+ * @since 1.5
+ * @author Doug Lea
+ * @param <V> The type of object referred to by this reference
+ */
+public class AtomicReference<V>  implements java.io.Serializable {
+    private static final long serialVersionUID = -1848883965231344442L;
+
+    private static final Unsafe unsafe = Unsafe.getUnsafe();
+    private static final long valueOffset;
+
+    static {
+      try {
+        valueOffset = unsafe.objectFieldOffset
+            (AtomicReference.class.getDeclaredField("value"));
+      } catch (Exception ex) { throw new Error(ex); }
+    }
+
+    private volatile V value;
+
+    /**
+     * Creates a new AtomicReference with the given initial value.
+     *
+     * @param initialValue the initial value
+     */
+    public AtomicReference(V initialValue) {
+        value = initialValue;
+    }
+
+    /**
+     * Creates a new AtomicReference with null initial value.
+     */
+    public AtomicReference() {
+    }
+
+    /**
+     * Gets the current value.
+     *
+     * @return the current value
+     */
+    public final V get() {
+        return value;
+    }
+
+    /**
+     * Sets to the given value.
+     *
+     * @param newValue the new value
+     */
+    public final void set(V newValue) {
+        value = newValue;
+    }
+
+    /**
+     * Eventually sets to the given value.
+     *
+     * @param newValue the new value
+     * @since 1.6
+     */
+    public final void lazySet(V newValue) {
+        unsafe.putOrderedObject(this, valueOffset, newValue);
+    }
+
+    /**
+     * Atomically sets the value to the given updated value
+     * if the current value <tt>==</tt> the expected value.
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful. False return indicates that
+     * the actual value was not equal to the expected value.
+     */
+    public final boolean compareAndSet(V expect, V update) {
+        return unsafe.compareAndSwapObject(this, valueOffset, expect, update);
+    }
+
+    /**
+     * Atomically sets the value to the given updated value
+     * if the current value <tt>==</tt> the expected value.
+     * May fail spuriously and does not provide ordering guarantees,
+     * so is only rarely an appropriate alternative to <tt>compareAndSet</tt>.
+     *
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful.
+     */
+    public final boolean weakCompareAndSet(V expect, V update) {
+        return unsafe.compareAndSwapObject(this, valueOffset, expect, update);
+    }
+
+    /**
+     * Atomically sets to the given value and returns the old value.
+     *
+     * @param newValue the new value
+     * @return the previous value
+     */
+    public final V getAndSet(V newValue) {
+        while (true) {
+            V x = get();
+            if (compareAndSet(x, newValue))
+                return x;
+        }
+    }
+
+    /**
+     * Returns the String representation of the current value.
+     * @return the String representation of the current value.
+     */
+    public String toString() {
+        return String.valueOf(get());
+    }
+
+}
diff --git a/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicReferenceArray.java b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicReferenceArray.java
new file mode 100644
index 000000000..91b601ed9
--- /dev/null
+++ b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicReferenceArray.java
@@ -0,0 +1,163 @@
+/*
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/licenses/publicdomain
+ */
+
+package java.util.concurrent.atomic;
+import sun.misc.Unsafe;
+import java.util.*;
+
+/**
+ * An array of object references in which elements may be updated
+ * atomically.  See the {@link java.util.concurrent.atomic} package
+ * specification for description of the properties of atomic
+ * variables.
+ * @since 1.5
+ * @author Doug Lea
+ * @param <E> The base class of elements held in this array
+ */
+public class AtomicReferenceArray<E> implements java.io.Serializable {
+    private static final long serialVersionUID = -6209656149925076980L;
+
+    private static final Unsafe unsafe = Unsafe.getUnsafe();
+    private static final int base = unsafe.arrayBaseOffset(Object[].class);
+    private static final int scale = unsafe.arrayIndexScale(Object[].class);
+    private final Object[] array;
+
+    private long rawIndex(int i) {
+        if (i < 0 || i >= array.length)
+            throw new IndexOutOfBoundsException("index " + i);
+        return base + i * scale;
+    }
+
+    /**
+     * Creates a new AtomicReferenceArray of given length.
+     * @param length the length of the array
+     */
+    public AtomicReferenceArray(int length) {
+        array = new Object[length];
+        // must perform at least one volatile write to conform to JMM
+        if (length > 0)
+            unsafe.putObjectVolatile(array, rawIndex(0), null);
+    }
+
+    /**
+     * Creates a new AtomicReferenceArray with the same length as, and
+     * all elements copied from, the given array.
+     *
+     * @param array the array to copy elements from
+     * @throws NullPointerException if array is null
+     */
+    public AtomicReferenceArray(E[] array) {
+        if (array == null)
+            throw new NullPointerException();
+        int length = array.length;
+        this.array = new Object[length];
+        if (length > 0) {
+            int last = length-1;
+            for (int i = 0; i < last; ++i)
+                this.array[i] = array[i];
+            // Do the last write as volatile
+            E e = array[last];
+            unsafe.putObjectVolatile(this.array, rawIndex(last), e);
+        }
+    }
+
+    /**
+     * Returns the length of the array.
+     *
+     * @return the length of the array
+     */
+    public final int length() {
+        return array.length;
+    }
+
+    /**
+     * Gets the current value at position <tt>i</tt>.
+     *
+     * @param i the index
+     * @return the current value
+     */
+    public final E get(int i) {
+        return (E) unsafe.getObjectVolatile(array, rawIndex(i));
+    }
+
+    /**
+     * Sets the element at position <tt>i</tt> to the given value.
+     *
+     * @param i the index
+     * @param newValue the new value
+     */
+    public final void set(int i, E newValue) {
+        unsafe.putObjectVolatile(array, rawIndex(i), newValue);
+    }
+
+    /**
+     * Eventually sets the element at position <tt>i</tt> to the given value.
+     *
+     * @param i the index
+     * @param newValue the new value
+     * @since 1.6
+     */
+    public final void lazySet(int i, E newValue) {
+        unsafe.putOrderedObject(array, rawIndex(i), newValue);
+    }
+
+
+    /**
+     * Atomically sets the element at position <tt>i</tt> to the given
+     * value and returns the old value.
+     *
+     * @param i the index
+     * @param newValue the new value
+     * @return the previous value
+     */
+    public final E getAndSet(int i, E newValue) {
+        while (true) {
+            E current = get(i);
+            if (compareAndSet(i, current, newValue))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically sets the element at position <tt>i</tt> to the given
+     * updated value if the current value <tt>==</tt> the expected value.
+     * @param i the index
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful. False return indicates that
+     * the actual value was not equal to the expected value.
+     */
+    public final boolean compareAndSet(int i, E expect, E update) {
+        return unsafe.compareAndSwapObject(array, rawIndex(i),
+                                         expect, update);
+    }
+
+    /**
+     * Atomically sets the element at position <tt>i</tt> to the given
+     * updated value if the current value <tt>==</tt> the expected value.
+     * May fail spuriously and does not provide ordering guarantees,
+     * so is only rarely an appropriate alternative to <tt>compareAndSet</tt>.
+     *
+     * @param i the index
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful.
+     */
+    public final boolean weakCompareAndSet(int i, E expect, E update) {
+        return compareAndSet(i, expect, update);
+    }
+
+    /**
+     * Returns the String representation of the current values of array.
+     * @return the String representation of the current values of array.
+     */
+    public String toString() {
+        if (array.length > 0) // force volatile read
+            get(0);
+        return Arrays.toString(array);
+    }
+
+}
diff --git a/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicReferenceFieldUpdater.java b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicReferenceFieldUpdater.java
new file mode 100644
index 000000000..24014a9df
--- /dev/null
+++ b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicReferenceFieldUpdater.java
@@ -0,0 +1,275 @@
+/*
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/licenses/publicdomain
+ */
+
+package java.util.concurrent.atomic;
+import sun.misc.Unsafe;
+import java.lang.reflect.*;
+
+/**
+ * A reflection-based utility that enables atomic updates to
+ * designated <tt>volatile</tt> reference fields of designated
+ * classes.  This class is designed for use in atomic data structures
+ * in which several reference fields of the same node are
+ * independently subject to atomic updates. For example, a tree node
+ * might be declared as
+ *
+ * <pre>
+ * class Node {
+ *   private volatile Node left, right;
+ *
+ *   private static final AtomicReferenceFieldUpdater&lt;Node, Node&gt; leftUpdater =
+ *     AtomicReferenceFieldUpdater.newUpdater(Node.class, Node.class, "left");
+ *   private static AtomicReferenceFieldUpdater&lt;Node, Node&gt; rightUpdater =
+ *     AtomicReferenceFieldUpdater.newUpdater(Node.class, Node.class, "right");
+ *
+ *   Node getLeft() { return left;  }
+ *   boolean compareAndSetLeft(Node expect, Node update) {
+ *     return leftUpdater.compareAndSet(this, expect, update);
+ *   }
+ *   // ... and so on
+ * }
+ * </pre>
+ *
+ * <p>Note that the guarantees of the {@code compareAndSet}
+ * method in this class are weaker than in other atomic classes.
+ * Because this class cannot ensure that all uses of the field
+ * are appropriate for purposes of atomic access, it can
+ * guarantee atomicity only with respect to other invocations of
+ * {@code compareAndSet} and {@code set} on the same updater.
+ *
+ * @since 1.5
+ * @author Doug Lea
+ * @param <T> The type of the object holding the updatable field
+ * @param <V> The type of the field
+ */
+public abstract class AtomicReferenceFieldUpdater<T, V>  {
+
+    /**
+     * Creates and returns an updater for objects with the given field.
+     * The Class arguments are needed to check that reflective types and
+     * generic types match.
+     *
+     * @param tclass the class of the objects holding the field.
+     * @param vclass the class of the field
+     * @param fieldName the name of the field to be updated.
+     * @return the updater
+     * @throws IllegalArgumentException if the field is not a volatile reference type.
+     * @throws RuntimeException with a nested reflection-based
+     * exception if the class does not hold field or is the wrong type.
+     */
+    public static <U, W> AtomicReferenceFieldUpdater<U,W> newUpdater(Class<U> tclass, Class<W> vclass, String fieldName) {
+        return new AtomicReferenceFieldUpdaterImpl<U,W>(tclass,
+                                                        vclass,
+                                                        fieldName);
+    }
+
+    /**
+     * Protected do-nothing constructor for use by subclasses.
+     */
+    protected AtomicReferenceFieldUpdater() {
+    }
+
+    /**
+     * Atomically sets the field of the given object managed by this updater
+     * to the given updated value if the current value <tt>==</tt> the
+     * expected value. This method is guaranteed to be atomic with respect to
+     * other calls to <tt>compareAndSet</tt> and <tt>set</tt>, but not
+     * necessarily with respect to other changes in the field.
+     *
+     * @param obj An object whose field to conditionally set
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful.
+     */
+    public abstract boolean compareAndSet(T obj, V expect, V update);
+
+    /**
+     * Atomically sets the field of the given object managed by this updater
+     * to the given updated value if the current value <tt>==</tt> the
+     * expected value. This method is guaranteed to be atomic with respect to
+     * other calls to <tt>compareAndSet</tt> and <tt>set</tt>, but not
+     * necessarily with respect to other changes in the field.
+     * May fail spuriously and does not provide ordering guarantees,
+     * so is only rarely an appropriate alternative to <tt>compareAndSet</tt>.
+     *
+     * @param obj An object whose field to conditionally set
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful.
+     */
+    public abstract boolean weakCompareAndSet(T obj, V expect, V update);
+
+    /**
+     * Sets the field of the given object managed by this updater to the
+     * given updated value. This operation is guaranteed to act as a volatile
+     * store with respect to subsequent invocations of
+     * <tt>compareAndSet</tt>.
+     *
+     * @param obj An object whose field to set
+     * @param newValue the new value
+     */
+    public abstract void set(T obj, V newValue);
+
+    /**
+     * Eventually sets the field of the given object managed by this
+     * updater to the given updated value.
+     *
+     * @param obj An object whose field to set
+     * @param newValue the new value
+     * @since 1.6
+     */
+    public abstract void lazySet(T obj, V newValue);
+
+    /**
+     * Gets the current value held in the field of the given object managed
+     * by this updater.
+     *
+     * @param obj An object whose field to get
+     * @return the current value
+     */
+    public abstract V get(T obj);
+
+    /**
+     * Atomically sets the field of the given object managed by this updater
+     * to the given value and returns the old value.
+     *
+     * @param obj An object whose field to get and set
+     * @param newValue the new value
+     * @return the previous value
+     */
+    public V getAndSet(T obj, V newValue) {
+        for (;;) {
+            V current = get(obj);
+            if (compareAndSet(obj, current, newValue))
+                return current;
+        }
+    }
+
+    private static final class AtomicReferenceFieldUpdaterImpl<T,V>
+        extends AtomicReferenceFieldUpdater<T,V> {
+        private static final Unsafe unsafe = Unsafe.getUnsafe();
+        private final long offset;
+        private final Class<T> tclass;
+        private final Class<V> vclass;
+        private final Class cclass;
+
+        /*
+         * Internal type checks within all update methods contain
+         * internal inlined optimizations checking for the common
+         * cases where the class is final (in which case a simple
+         * getClass comparison suffices) or is of type Object (in
+         * which case no check is needed because all objects are
+         * instances of Object). The Object case is handled simply by
+         * setting vclass to null in constructor.  The targetCheck and
+         * updateCheck methods are invoked when these faster
+         * screenings fail.
+         */
+
+        AtomicReferenceFieldUpdaterImpl(Class<T> tclass,
+                                        Class<V> vclass,
+                                        String fieldName) {
+            Field field = null;
+            Class fieldClass = null;
+            Class caller = null;
+            int modifiers = 0;
+            try {
+                field = tclass.getDeclaredField(fieldName);
+                caller = sun.reflect.Reflection.getCallerClass(3);
+                modifiers = field.getModifiers();
+                sun.reflect.misc.ReflectUtil.ensureMemberAccess(
+                    caller, tclass, null, modifiers);
+                sun.reflect.misc.ReflectUtil.checkPackageAccess(tclass);
+                fieldClass = field.getType();
+            } catch (Exception ex) {
+                throw new RuntimeException(ex);
+            }
+
+            if (vclass != fieldClass)
+                throw new ClassCastException();
+
+            if (!Modifier.isVolatile(modifiers))
+                throw new IllegalArgumentException("Must be volatile type");
+
+            this.cclass = (Modifier.isProtected(modifiers) &&
+                           caller != tclass) ? caller : null;
+            this.tclass = tclass;
+            if (vclass == Object.class)
+                this.vclass = null;
+            else
+                this.vclass = vclass;
+            offset = unsafe.objectFieldOffset(field);
+        }
+
+        void targetCheck(T obj) {
+            if (!tclass.isInstance(obj))
+                throw new ClassCastException();
+            if (cclass != null)
+                ensureProtectedAccess(obj);
+        }
+
+        void updateCheck(T obj, V update) {
+            if (!tclass.isInstance(obj) ||
+                (update != null && vclass != null && !vclass.isInstance(update)))
+                throw new ClassCastException();
+            if (cclass != null)
+                ensureProtectedAccess(obj);
+        }
+
+        public boolean compareAndSet(T obj, V expect, V update) {
+            if (obj == null || obj.getClass() != tclass || cclass != null ||
+                (update != null && vclass != null &&
+                 vclass != update.getClass()))
+                updateCheck(obj, update);
+            return unsafe.compareAndSwapObject(obj, offset, expect, update);
+        }
+
+        public boolean weakCompareAndSet(T obj, V expect, V update) {
+            // same implementation as strong form for now
+            if (obj == null || obj.getClass() != tclass || cclass != null ||
+                (update != null && vclass != null &&
+                 vclass != update.getClass()))
+                updateCheck(obj, update);
+            return unsafe.compareAndSwapObject(obj, offset, expect, update);
+        }
+
+        public void set(T obj, V newValue) {
+            if (obj == null || obj.getClass() != tclass || cclass != null ||
+                (newValue != null && vclass != null &&
+                 vclass != newValue.getClass()))
+                updateCheck(obj, newValue);
+            unsafe.putObjectVolatile(obj, offset, newValue);
+        }
+
+        public void lazySet(T obj, V newValue) {
+            if (obj == null || obj.getClass() != tclass || cclass != null ||
+                (newValue != null && vclass != null &&
+                 vclass != newValue.getClass()))
+                updateCheck(obj, newValue);
+            unsafe.putOrderedObject(obj, offset, newValue);
+        }
+
+        public V get(T obj) {
+            if (obj == null || obj.getClass() != tclass || cclass != null)
+                targetCheck(obj);
+            return (V)unsafe.getObjectVolatile(obj, offset);
+        }
+
+        private void ensureProtectedAccess(T obj) {
+            if (cclass.isInstance(obj)) {
+                return;
+            }
+            throw new RuntimeException (
+                new IllegalAccessException("Class " +
+                    cclass.getName() +
+                    " can not access a protected member of class " +
+                    tclass.getName() +
+                    " using an instance of " +
+                    obj.getClass().getName()
+                )
+            );
+        }
+    }
+}
diff --git a/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicStampedReference.java b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicStampedReference.java
new file mode 100644
index 000000000..558808216
--- /dev/null
+++ b/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicStampedReference.java
@@ -0,0 +1,165 @@
+/*
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/licenses/publicdomain
+ */
+
+package java.util.concurrent.atomic;
+
+/**
+ * An <tt>AtomicStampedReference</tt> maintains an object reference
+ * along with an integer "stamp", that can be updated atomically.
+ *
+ * <p> Implementation note. This implementation maintains stamped
+ * references by creating internal objects representing "boxed"
+ * [reference, integer] pairs.
+ *
+ * @since 1.5
+ * @author Doug Lea
+ * @param <V> The type of object referred to by this reference
+ */
+public class AtomicStampedReference<V>  {
+
+    private static class ReferenceIntegerPair<T> {
+        private final T reference;
+        private final int integer;
+        ReferenceIntegerPair(T r, int i) {
+            reference = r; integer = i;
+        }
+    }
+
+    private final AtomicReference<ReferenceIntegerPair<V>>  atomicRef;
+
+    /**
+     * Creates a new <tt>AtomicStampedReference</tt> with the given
+     * initial values.
+     *
+     * @param initialRef the initial reference
+     * @param initialStamp the initial stamp
+     */
+    public AtomicStampedReference(V initialRef, int initialStamp) {
+        atomicRef = new AtomicReference<ReferenceIntegerPair<V>>
+            (new ReferenceIntegerPair<V>(initialRef, initialStamp));
+    }
+
+    /**
+     * Returns the current value of the reference.
+     *
+     * @return the current value of the reference
+     */
+    public V getReference() {
+        return atomicRef.get().reference;
+    }
+
+    /**
+     * Returns the current value of the stamp.
+     *
+     * @return the current value of the stamp
+     */
+    public int getStamp() {
+        return atomicRef.get().integer;
+    }
+
+    /**
+     * Returns the current values of both the reference and the stamp.
+     * Typical usage is <tt>int[1] holder; ref = v.get(holder); </tt>.
+     *
+     * @param stampHolder an array of size of at least one.  On return,
+     * <tt>stampholder[0]</tt> will hold the value of the stamp.
+     * @return the current value of the reference
+     */
+    public V get(int[] stampHolder) {
+        ReferenceIntegerPair<V> p = atomicRef.get();
+        stampHolder[0] = p.integer;
+        return p.reference;
+    }
+
+    /**
+     * Atomically sets the value of both the reference and stamp
+     * to the given update values if the
+     * current reference is <tt>==</tt> to the expected reference
+     * and the current stamp is equal to the expected stamp.
+     * May fail spuriously and does not provide ordering guarantees,
+     * so is only rarely an appropriate alternative to <tt>compareAndSet</tt>.
+     *
+     * @param expectedReference the expected value of the reference
+     * @param newReference the new value for the reference
+     * @param expectedStamp the expected value of the stamp
+     * @param newStamp the new value for the stamp
+     * @return true if successful
+     */
+    public boolean weakCompareAndSet(V      expectedReference,
+                                     V      newReference,
+                                     int    expectedStamp,
+                                     int    newStamp) {
+        ReferenceIntegerPair<V> current = atomicRef.get();
+        return  expectedReference == current.reference &&
+            expectedStamp == current.integer &&
+            ((newReference == current.reference &&
+              newStamp == current.integer) ||
+             atomicRef.weakCompareAndSet(current,
+                                     new ReferenceIntegerPair<V>(newReference,
+                                                              newStamp)));
+    }
+
+    /**
+     * Atomically sets the value of both the reference and stamp
+     * to the given update values if the
+     * current reference is <tt>==</tt> to the expected reference
+     * and the current stamp is equal to the expected stamp.
+     *
+     * @param expectedReference the expected value of the reference
+     * @param newReference the new value for the reference
+     * @param expectedStamp the expected value of the stamp
+     * @param newStamp the new value for the stamp
+     * @return true if successful
+     */
+    public boolean compareAndSet(V      expectedReference,
+                                 V      newReference,
+                                 int    expectedStamp,
+                                 int    newStamp) {
+        ReferenceIntegerPair<V> current = atomicRef.get();
+        return  expectedReference == current.reference &&
+            expectedStamp == current.integer &&
+            ((newReference == current.reference &&
+              newStamp == current.integer) ||
+             atomicRef.compareAndSet(current,
+                                     new ReferenceIntegerPair<V>(newReference,
+                                                              newStamp)));
+    }
+
+
+    /**
+     * Unconditionally sets the value of both the reference and stamp.
+     *
+     * @param newReference the new value for the reference
+     * @param newStamp the new value for the stamp
+     */
+    public void set(V newReference, int newStamp) {
+        ReferenceIntegerPair<V> current = atomicRef.get();
+        if (newReference != current.reference || newStamp != current.integer)
+            atomicRef.set(new ReferenceIntegerPair<V>(newReference, newStamp));
+    }
+
+    /**
+     * Atomically sets the value of the stamp to the given update value
+     * if the current reference is <tt>==</tt> to the expected
+     * reference.  Any given invocation of this operation may fail
+     * (return <tt>false</tt>) spuriously, but repeated invocation
+     * when the current value holds the expected value and no other
+     * thread is also attempting to set the value will eventually
+     * succeed.
+     *
+     * @param expectedReference the expected value of the reference
+     * @param newStamp the new value for the stamp
+     * @return true if successful
+     */
+    public boolean attemptStamp(V expectedReference, int newStamp) {
+        ReferenceIntegerPair<V> current = atomicRef.get();
+        return  expectedReference == current.reference &&
+            (newStamp == current.integer ||
+             atomicRef.compareAndSet(current,
+                                     new ReferenceIntegerPair<V>(expectedReference,
+                                                              newStamp)));
+    }
+}