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/* |
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* $Id$ |
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* |
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* Copyright (C) 2003-2009 JNode.org |
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* |
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* This library is free software; you can redistribute it and/or modify it |
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* under the terms of the GNU Lesser General Public License as published |
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* by the Free Software Foundation; either version 2.1 of the License, or |
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* (at your option) any later version. |
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* |
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* This library is distributed in the hope that it will be useful, but |
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* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
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* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public |
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* License for more details. |
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* |
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* You should have received a copy of the GNU Lesser General Public License |
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* along with this library; If not, write to the Free Software Foundation, Inc., |
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
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*/ |
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|
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package org.jnode.vm; |
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|
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import org.jnode.vm.classmgr.VmByteCode; |
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import org.jnode.vm.classmgr.VmMethod; |
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import org.jnode.vm.classmgr.VmType; |
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|
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/** |
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* A VmFrame is the execution frame (locals & stack) for a method during |
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* execution. Note that this class is not meant to be a normal java class, |
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* instead it is a record structure that maps directly on how a method frame is |
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* push on the stack by the compiler. Don't add any methods, since during |
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* runtime instances of this class will have no header and thus no virtual |
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* method table. |
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*/ |
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public final class VmStackFrame extends VmSystemObject { |
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|
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public static final int MAGIC_MASK = 0xFFFFFF00; |
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public static final int MAGIC_COMPILED = 0x21A52F00; |
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|
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/** |
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* The method executing in this frame |
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*/ |
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private final VmMethod sfMethod; |
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private final int programCounter; |
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|
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/** |
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* Initialize this instance. |
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* |
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* @param src |
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* @param reader |
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*/ |
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VmStackFrame(VmMethod method, int programCounter) { |
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this.sfMethod = method; |
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this.programCounter = programCounter; |
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} |
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|
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/** |
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* @return Returns the method. |
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*/ |
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public final VmMethod getMethod() { |
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return this.sfMethod; |
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} |
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|
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/** |
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* Gets the line number of the current instruction of this frame. |
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* |
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* @return The line number, or -1 if not found. |
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*/ |
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public final String getLocationInfo() { |
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int lineNo = -1; |
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if (sfMethod != null) { |
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final VmByteCode bc = sfMethod.getBytecode(); |
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if (bc != null) { |
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lineNo = bc.getLineNr(programCounter); |
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} |
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} |
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if (lineNo >= 0) { |
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return String.valueOf(lineNo); |
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} else { |
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return "?"; |
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} |
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} |
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|
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/** |
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* Convert to a String representation. |
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* |
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* @see java.lang.Object#toString() |
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*/ |
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public String toString() { |
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final VmMethod method = sfMethod; |
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final VmType<?> vmClass = (method == null) ? null : method.getDeclaringClass(); |
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final String cname = (vmClass == null) ? "<unknown class>" : vmClass.getName(); |
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final String mname = (method == null) ? "<unknown method>" : method.getName(); |
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final String location = getLocationInfo(); |
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|
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return cname + "!" + mname + " (" + location + ")"; |
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} |
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} |
