Start for a basic atomic implementation for avian. Still need to figure out how to do the Array versions of these. But I wanted to wait till we have the needed Unsafe implementation and add testing for these before we go further.

classpath/java/util/concurrent/atomic/AtomicBoolean.java

@@ -0,0 +1,61 @@
+package java.util.concurrent.atomic;
+
+public class AtomicBoolean implements java.io.Serializable {
+  private static final long serialVersionUID = 4654671469794556979L;
+  
+  private static final int FALSE_VALUE = 0;
+  private static final int TRUE_VALUE = 1;
+  
+  private final AtomicInteger value;
+  
+  public AtomicBoolean() {
+    this(false);
+  }
+  
+  public AtomicBoolean(boolean initialValue) {
+    value = new AtomicInteger(intValue(initialValue));
+  }
+  
+  private static int intValue(boolean value) {
+    return value ? TRUE_VALUE : FALSE_VALUE;
+  }
+  
+  private static boolean booleanValue(int value) {
+    if (value == TRUE_VALUE) {
+      return true;
+    } else {
+      return false;
+    }
+  }
+  
+  public boolean get() {
+    return booleanValue(value.get());
+  }
+  
+  public boolean compareAndSet(boolean expect, boolean update) {
+    return value.compareAndSet(intValue(expect), intValue(update));
+  }
+  
+  public boolean weakCompareAndSet(boolean expect, boolean update) {
+    return value.weakCompareAndSet(intValue(expect), intValue(update));
+  }
+  
+  public void set(boolean newValue) {
+    value.set(intValue(newValue));
+  }
+  
+  public void lazySet(boolean newValue) {
+    value.lazySet(intValue(newValue));
+  }
+  
+  public boolean getAndSet(boolean newValue) {
+    int intResult = value.getAndSet(intValue(newValue));
+    
+    return booleanValue(intResult);
+  }
+  
+  @Override
+  public String toString() {
+    return Boolean.toString(get());
+  }
+}

classpath/java/util/concurrent/atomic/AtomicInteger.java

@@ -0,0 +1,126 @@
+package java.util.concurrent.atomic;
+
+import java.lang.reflect.Field;
+
+import sun.misc.Unsafe;
+
+public class AtomicInteger extends Number implements java.io.Serializable {
+  private static final long serialVersionUID = 6214790243416807050L;
+  
+  private static final Unsafe unsafe = Unsafe.getUnsafe();
+  private static final long valueOffset;
+  
+  static {
+    try {
+      Field<?> f = AtomicInteger.class.getDeclaredField("value");
+      valueOffset = unsafe.objectFieldOffset(f);
+    } catch (NoSuchFieldException e) {
+      throw new Error(e);
+    }
+  }
+  
+  private volatile int value;
+  
+  public AtomicInteger() {
+    this(0);
+  }
+  
+  public AtomicInteger(int initialValue) {
+    this.value = initialValue;
+  }
+  
+  public int get() {
+    return value;
+  }
+  
+  public void set(int newValue) {
+    this.value = newValue;
+  }
+  
+  public void lazySet(int newValue) {
+    unsafe.putOrderedInt(this, valueOffset, newValue);
+  }
+  
+  public boolean compareAndSet(int expect, int update) {
+    return unsafe.compareAndSwapInt(this, valueOffset, expect, update);
+  }
+  
+  public boolean weakCompareAndSet(int expect, int update) {
+    return unsafe.compareAndSwapInt(this, valueOffset, expect, update);
+  }
+  
+  public int getAndSet(int newValue) {
+    while (true) {
+      int current = value;
+      if (compareAndSet(current, newValue)) {
+        return current;
+      }
+    }
+  }
+  
+  public int getAndAdd(int delta) {
+    while (true) {
+      int current = value;
+      int next = current + delta;
+      if (compareAndSet(current, next)) {
+        return current;
+      }
+    }
+  }
+  
+  public int getAndIncrement() {
+    return getAndAdd(1);
+  }
+  
+  public int getAndDecrement() {
+    return getAndAdd(-1);
+  }
+  
+  public int addAndGet(int delta) {
+    while (true) {
+      int current = value;
+      int next = current + delta;
+      if (compareAndSet(current, next)) {
+        return next;
+      }
+    }
+  }
+  
+  public int incrementAndGet() {
+    return addAndGet(1);
+  }
+  
+  public int decrementAndGet() {
+    return addAndGet(-1);
+  }
+  
+  @Override
+  public byte byteValue() {
+    return (byte)value;
+  }
+
+  @Override
+  public short shortValue() {
+    return (short)value;
+  }
+
+  @Override
+  public int intValue() {
+    return value;
+  }
+
+  @Override
+  public long longValue() {
+    return value;
+  }
+
+  @Override
+  public float floatValue() {
+    return value;
+  }
+
+  @Override
+  public double doubleValue() {
+    return value;
+  }
+}

classpath/java/util/concurrent/atomic/AtomicLong.java

@@ -0,0 +1,126 @@
+package java.util.concurrent.atomic;
+
+import java.lang.reflect.Field;
+
+import sun.misc.Unsafe;
+
+public class AtomicLong extends Number implements java.io.Serializable {
+  private static final long serialVersionUID = 1927816293512124184L;
+  
+  private static final Unsafe unsafe = Unsafe.getUnsafe();
+  private static final long valueOffset;
+  
+  static {
+    try {
+      Field<?> f = AtomicLong.class.getDeclaredField("value");
+      valueOffset = unsafe.objectFieldOffset(f);
+    } catch (NoSuchFieldException e) {
+      throw new Error(e);
+    }
+  }
+  
+  private volatile long value;
+  
+  public AtomicLong() {
+    this(0);
+  }
+  
+  public AtomicLong(long initialValue) {
+    this.value = initialValue;
+  }
+  
+  public long get() {
+    return value;
+  }
+  
+  public void set(long newValue) {
+    this.value = newValue;
+  }
+  
+  public void lazySet(long newValue) {
+    unsafe.putOrderedLong(this, valueOffset, newValue);
+  }
+  
+  public boolean compareAndSet(long expect, long update) {
+    return unsafe.compareAndSwapLong(this, valueOffset, expect, update);
+  }
+  
+  public boolean weakCompareAndSet(long expect, long update) {
+    return unsafe.compareAndSwapLong(this, valueOffset, expect, update);
+  }
+  
+  public long getAndSet(long newValue) {
+    while (true) {
+      long current = value;
+      if (compareAndSet(current, newValue)) {
+        return current;
+      }
+    }
+  }
+  
+  public long getAndAdd(long delta) {
+    while (true) {
+      long current = value;
+      long next = current + delta;
+      if (compareAndSet(current, next)) {
+        return current;
+      }
+    }
+  }
+  
+  public long getAndIncrement() {
+    return getAndAdd(1);
+  }
+  
+  public long getAndDecrement() {
+    return getAndAdd(-1);
+  }
+  
+  public long addAndGet(long delta) {
+    while (true) {
+      long current = value;
+      long next = current + delta;
+      if (compareAndSet(current, next)) {
+        return next;
+      }
+    }
+  }
+  
+  public long incrementAndGet() {
+    return addAndGet(1);
+  }
+  
+  public long decrementAndGet() {
+    return addAndGet(-1);
+  }
+  
+  @Override
+  public byte byteValue() {
+    return (byte)value;
+  }
+
+  @Override
+  public short shortValue() {
+    return (short)value;
+  }
+
+  @Override
+  public int intValue() {
+    return (int)value;
+  }
+
+  @Override
+  public long longValue() {
+    return value;
+  }
+
+  @Override
+  public float floatValue() {
+    return value;
+  }
+
+  @Override
+  public double doubleValue() {
+    return value;
+  }
+}

classpath/java/util/concurrent/atomic/AtomicReference.java

@@ -0,0 +1,61 @@
+package java.util.concurrent.atomic;
+
+import java.lang.reflect.Field;
+
+import sun.misc.Unsafe;
+
+public class AtomicReference<T> implements java.io.Serializable {
+  private static final long serialVersionUID = -1848883965231344442L;
+  
+  private static final Unsafe unsafe = Unsafe.getUnsafe();
+  private static final long valueOffset;
+  
+  static {
+    try {
+      Field<?> f = AtomicReference.class.getDeclaredField("value");
+      valueOffset = unsafe.objectFieldOffset(f);
+    } catch (NoSuchFieldException e) {
+      throw new Error(e);
+    }
+  }
+  
+  private volatile T value;
+  
+  public AtomicReference() {
+    this(null);
+  }
+  
+  public AtomicReference(T initialValue) {
+    this.value = initialValue;
+  }
+  
+  public T get() {
+    return value;
+  }
+  
+  public void lazySet(T newValue) {
+    unsafe.putOrderedObject(this, valueOffset, newValue);
+  }
+  
+  public boolean compareAndSet(T expect, T update) {
+    return unsafe.compareAndSwapObject(this, valueOffset, expect, update);
+  }
+  
+  public boolean weakCompareAndSet(T expect, T update) {
+    return unsafe.compareAndSwapObject(this, valueOffset, expect, update);
+  }
+  
+  public final T getAndSet(T newValue) {
+    while (true) {
+      T current = value;
+      if (compareAndSet(current, newValue)) {
+        return current;
+      }
+    }
+  }
+  
+  @Override
+  public String toString() {
+    return String.valueOf(value);
+  }
+}