| /* |
| * Copyright (c) 2000, 2002, 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. |
| * |
| * 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 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"); |
| } |
| } |
| } |