--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/main/gov/nasa/jpf/vm/AtomicData.java	Fri Jan 23 10:14:01 2015 -0800
@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) 2014, United States Government, as represented by the
+ * Administrator of the National Aeronautics and Space Administration.
+ * All rights reserved.
+ *
+ * The Java Pathfinder core (jpf-core) platform is licensed under the
+ * Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ * 
+ *        http://www.apache.org/licenses/LICENSE-2.0. 
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and 
+ * limitations under the License.
+ */
+package gov.nasa.jpf.vm;
+
+import gov.nasa.jpf.util.HashData;
+
+
+/**
+ * helper object to store per thread information about atomic line
+ * execution
+ * <2do> check if we can't do this less expensive. atomic-lines is not
+ * the default anymore
+ */
+public class AtomicData {
+  /**
+   * The method in which the line step started.
+   */
+  public MethodInfo currentMethod;
+
+  /**
+   * The line at which the line step started.
+   */
+  public int line;
+
+  /**
+   * Set to true if we still are in the same method in which we were
+   * when the line step started.
+   */
+  public boolean inSameMethod;
+
+  @Override
+  public Object clone () {
+    AtomicData a = new AtomicData();
+
+    a.currentMethod = currentMethod;
+    a.line = line;
+    a.inSameMethod = inSameMethod;
+
+    return a;
+  }
+
+  @Override
+  public boolean equals (Object o) {
+    if (o == null) {
+      return false;
+    }
+
+    if (!(o instanceof AtomicData)) {
+      return false;
+    }
+
+    AtomicData a = (AtomicData) o;
+
+    if (currentMethod != a.currentMethod) {
+      return false;
+    }
+
+    if (line != a.line) {
+      return false;
+    }
+
+    if (inSameMethod != a.inSameMethod) {
+      return false;
+    }
+
+    return true;
+  }
+
+  /**
+   * Computes a hash code with the object data.
+   */
+  public void hash (HashData hd) {
+    hd.add(line);
+    hd.add(inSameMethod ? 1 : 0);
+  }
+
+  /**
+   * Returns a hash code for the object.
+   */
+  @Override
+  public int hashCode () {
+    HashData hd = new HashData();
+
+    hash(hd);
+
+    return hd.getValue();
+  }
+}