--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/agent/src/share/classes/sun/jvm/hotspot/code/StubQueue.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,174 @@
+/*
+ * Copyright 2000-2002 Sun Microsystems, Inc.  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.
+ *
+ * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+package sun.jvm.hotspot.code;
+
+import java.util.*;
+import sun.jvm.hotspot.debugger.*;
+import sun.jvm.hotspot.runtime.*;
+import sun.jvm.hotspot.types.*;
+import sun.jvm.hotspot.utilities.*;
+
+/** <P> A port of the VM's StubQueue. Note that the VM implicitly
+    knows the type of the objects contained in each StubQueue because
+    it passes in an instance of a StubInterface to the StubQueue's
+    constructor; the goal in the VM was to save space in the generated
+    code. In the SA APIs the pattern has been to use the
+    VirtualConstructor mechanism to instantiate wrapper objects of the
+    appropriate type for objects down in the VM; see, for example, the
+    CodeCache, which identifies NMethods, RuntimeStubs, etc. </P>
+
+    <P> In this port we eliminate the StubInterface in favor of
+    passing in the class corresponding to the type of Stub which this
+    StubQueue contains. </P> */
+
+public class StubQueue extends VMObject {
+  // FIXME: add the rest of the fields
+  private static AddressField  stubBufferField;
+  private static CIntegerField bufferLimitField;
+  private static CIntegerField queueBeginField;
+  private static CIntegerField queueEndField;
+  private static CIntegerField numberOfStubsField;
+
+  // The type of the contained stubs (i.e., InterpreterCodelet,
+  // ICStub). Must be a subclass of type Stub.
+  private Class stubType;
+
+  static {
+    VM.registerVMInitializedObserver(new Observer() {
+        public void update(Observable o, Object data) {
+          initialize(VM.getVM().getTypeDataBase());
+        }
+      });
+  }
+
+  private static synchronized void initialize(TypeDataBase db) {
+    Type type = db.lookupType("StubQueue");
+
+    stubBufferField    = type.getAddressField("_stub_buffer");
+    bufferLimitField   = type.getCIntegerField("_buffer_limit");
+    queueBeginField    = type.getCIntegerField("_queue_begin");
+    queueEndField      = type.getCIntegerField("_queue_end");
+    numberOfStubsField = type.getCIntegerField("_number_of_stubs");
+  }
+
+  public StubQueue(Address addr, Class stubType) {
+    super(addr);
+    this.stubType = stubType;
+  }
+
+  public boolean contains(Address pc) {
+    if (pc == null) return false;
+    long offset = pc.minus(getStubBuffer());
+    return ((0 <= offset) && (offset < getBufferLimit()));
+  }
+
+  public Stub getStubContaining(Address pc) {
+    if (contains(pc)) {
+      int i = 0;
+      for (Stub s = getFirst(); s != null; s = getNext(s)) {
+        if (stubContains(s, pc)) {
+          return s;
+        }
+      }
+    }
+    return null;
+  }
+
+  public boolean stubContains(Stub s, Address pc) {
+    return (s.codeBegin().lessThanOrEqual(pc) && s.codeEnd().greaterThan(pc));
+  }
+
+  public int getNumberOfStubs() {
+    return (int) numberOfStubsField.getValue(addr);
+  }
+
+  public Stub getFirst() {
+    return ((getNumberOfStubs() > 0) ? getStubAt(getQueueBegin()) : null);
+  }
+
+  public Stub getNext(Stub s) {
+    long i = getIndexOf(s) + getStubSize(s);
+    if (i == getBufferLimit()) {
+      i = 0;
+    }
+    return ((i == getQueueEnd()) ? null : getStubAt(i));
+  }
+
+  public Stub getPrev(Stub s) {
+    if (getIndexOf(s) == getQueueBegin()) {
+       return null;
+    }
+
+    Stub temp = getFirst();
+    Stub prev = null;
+    while (temp != null && getIndexOf(temp) != getIndexOf(s)) {
+       prev = temp;
+       temp  = getNext(temp);
+    }
+
+    return prev;
+  }
+
+  //--------------------------------------------------------------------------------
+  // Internals only below this point
+  //
+
+  private long getQueueBegin() {
+    return queueBeginField.getValue(addr);
+  }
+
+  private long getQueueEnd() {
+    return queueEndField.getValue(addr);
+  }
+
+  private long getBufferLimit() {
+    return bufferLimitField.getValue(addr);
+  }
+
+  private Address getStubBuffer() {
+    return stubBufferField.getValue(addr);
+  }
+
+  private Stub getStubAt(long offset) {
+    checkIndex(offset);
+    return (Stub) VMObjectFactory.newObject(stubType, getStubBuffer().addOffsetTo(offset));
+  }
+
+  private long getIndexOf(Stub s) {
+    long i = s.getAddress().minus(getStubBuffer());
+    checkIndex(i);
+    return i;
+  }
+
+  private long getStubSize(Stub s) {
+    return s.getSize();
+  }
+
+  private void checkIndex(long i) {
+    if (Assert.ASSERTS_ENABLED) {
+      Assert.that(0 <= i && i < getBufferLimit() && (i % VM.getVM().getAddressSize() == 0), "illegal index");
+    }
+  }
+}