--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/langtools/src/share/classes/com/sun/tools/javac/comp/CompileStates.java	Sat Apr 13 12:25:44 2013 +0100
@@ -0,0 +1,92 @@
+/*
+ * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package com.sun.tools.javac.comp;
+
+import java.util.HashMap;
+
+import com.sun.tools.javac.util.Context;
+
+/** Partial map to record which compiler phases have been executed
+ *  for each compilation unit. Used for ATTR and FLOW phases.
+ *
+ *  <p><b>This is NOT part of any supported API.
+ *  If you write code that depends on this, you do so at your own risk.
+ *  This code and its internal interfaces are subject to change or
+ *  deletion without notice.</b>
+ */
+public class CompileStates extends HashMap<Env<AttrContext>, CompileStates.CompileState> {
+    /** The context key for the compile states. */
+    protected static final Context.Key<CompileStates> compileStatesKey =
+        new Context.Key<CompileStates>();
+
+    /** Get the CompileStates instance for this context. */
+    public static CompileStates instance(Context context) {
+        CompileStates instance = context.get(compileStatesKey);
+        if (instance == null) {
+            instance = new CompileStates(context);
+        }
+        return instance;
+    }
+
+    /** Ordered list of compiler phases for each compilation unit. */
+    public enum CompileState {
+        INIT(0),
+        PARSE(1),
+        ENTER(2),
+        PROCESS(3),
+        ATTR(4),
+        FLOW(5),
+        TRANSTYPES(6),
+        UNLAMBDA(7),
+        LOWER(8),
+        GENERATE(9);
+
+        CompileState(int value) {
+            this.value = value;
+        }
+        public boolean isAfter(CompileState other) {
+            return value > other.value;
+        }
+        public static CompileState max(CompileState a, CompileState b) {
+            return a.value > b.value ? a : b;
+        }
+        private final int value;
+    };
+
+    private static final long serialVersionUID = 1812267524140424433L;
+
+    protected Context context;
+
+    public CompileStates(Context context) {
+        this.context = context;
+        context.put(compileStatesKey, this);
+    }
+
+    public boolean isDone(Env<AttrContext> env, CompileState cs) {
+        CompileState ecs = get(env);
+        return (ecs != null) && !cs.isAfter(ecs);
+    }
+}