git-svn-id: https://svn.code.sf.net/p/jode/code/trunk@78 379699f6-c40d-0410-875b-85095c16579estable
jochen
27 years ago
parent
e2b966818c
commit
dff23235cc
@ -0,0 +1,812 @@ |
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/* TransformExceptionHandlers Copyright (C) 1997-1998 Jochen Hoenicke. |
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* |
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* This program is free software; you can redistribute it and/or modify |
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* it under the terms of the GNU General Public License as published by |
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* the Free Software Foundation; either version 2, or (at your option) |
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* any later version. |
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* |
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* This program is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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* GNU General Public License for more details. |
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* |
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* You should have received a copy of the GNU General Public License |
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* along with this program; see the file COPYING. If not, write to |
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* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. |
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* |
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* $Id$ |
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*/ |
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package jode.flow; |
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import jode.AssertError; |
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import jode.Type; |
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import jode.LocalInfo; |
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import jode.ComplexExpression; |
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import jode.LocalStoreOperator; |
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import jode.NopOperator; |
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import jode.MonitorExitOperator; |
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import jode.LocalLoadOperator; |
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import jode.Expression; |
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import jode.PopOperator; |
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import java.util.Enumeration; |
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import java.util.Stack; |
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|
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/** |
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* |
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* @author Jochen Hoenicke |
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*/ |
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public class TransformExceptionHandlers { |
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FlowBlock[] flows; |
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int count; |
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int[] startPCs = new int[4]; |
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int[] endPCs = new int[4]; |
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int[] handlerPCs = new int[4]; |
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Type[] types = new Type[4]; |
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|
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public TransformExceptionHandlers(FlowBlock[] flowBlocks) { |
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flows = flowBlocks; |
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count = 0; |
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} |
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|
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/** |
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* Add an exception Handler. |
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* @param start The start address of the exception range. |
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* @param end The end address of the exception range + 1. |
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* @param handler The address of the handler. |
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* @param type The type of the exception, null for ALL. |
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*/ |
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public void addHandler(int start, int end, int handler, Type type) { |
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int offset = 0; |
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/* First sort by start offsets, highest address first...*/ |
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while (offset < count && start < startPCs[offset]) |
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offset++; |
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/* ...Second sort by end offsets, lowest address first... |
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* this will move the innermost blocks to the beginning. */ |
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while (offset < count && start == startPCs[offset] |
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&& end > endPCs[offset]) |
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offset++; |
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/* ...Last sort by handler offsets, lowest first */ |
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while (offset < count && start == startPCs[offset] |
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&& end == endPCs[offset] && handler > handlerPCs[offset]) |
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offset++; |
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|
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if (count++ >= startPCs.length) { |
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/* We grow the arrays by 50 % */ |
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int newSize = startPCs.length * 3 / 2; |
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int[] newStartPCs = new int[newSize]; |
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int[] newEndPCs = new int[newSize]; |
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int[] newHandlerPCs = new int[newSize]; |
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Type[] newTypes = new Type[newSize]; |
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System.arraycopy(startPCs, 0, newStartPCs, 0, offset); |
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System.arraycopy(endPCs, 0, newEndPCs, 0, offset); |
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System.arraycopy(handlerPCs, 0, newHandlerPCs, 0, offset); |
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System.arraycopy(types, 0, newTypes, 0, offset); |
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|
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if (offset+1 < count) { |
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System.arraycopy(startPCs, offset, newStartPCs, offset+1, |
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count-offset-1); |
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System.arraycopy(endPCs, offset, newEndPCs, offset+1, |
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count-offset-1); |
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System.arraycopy(handlerPCs, offset, newHandlerPCs, offset+1, |
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count-offset-1); |
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System.arraycopy(types, offset, newTypes, offset+1, |
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count-offset-1); |
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} |
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startPCs = newStartPCs; |
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endPCs = newEndPCs; |
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handlerPCs = newHandlerPCs; |
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types = newTypes; |
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} else if (offset+1 < count) { |
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/* Move the tailing data one place below |
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*/ |
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System.arraycopy(startPCs, offset, startPCs, offset+1, |
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count-offset-1); |
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System.arraycopy(endPCs, offset, endPCs, offset+1, |
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count-offset-1); |
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System.arraycopy(handlerPCs, offset, handlerPCs, offset+1, |
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count-offset-1); |
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System.arraycopy(types, offset, types, offset+1, |
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count-offset-1); |
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} |
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/* Insert the new handler */ |
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startPCs[offset] = start; |
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endPCs[offset] = end; |
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handlerPCs[offset] = handler; |
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types[offset] = type; |
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} |
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|
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/** |
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* Updates the in/out-Vectors of the structured block of the |
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* successing flow block for a try catch block. The main difference |
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* to updateInOut in FlowBlock is, that this function works, as if |
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* every instruction would have a jump. This is because every |
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* instruction can throw an exception and thus enter the catch block. |
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* |
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* @param successor The flow block which is unified with this flow |
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* block. |
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* @return The variables that must be defined in this block. |
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*/ |
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static void updateInOutCatch (FlowBlock tryFlow, FlowBlock catchFlow) { |
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VariableSet gens = ((TryBlock)tryFlow.block).gen; |
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|
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/* Merge the locals used in the catch block with those written |
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* by the try block |
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*/ |
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catchFlow.in.merge(gens); |
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|
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/* The gen/kill sets must be updated for every jump |
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* in the catch block */ |
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Enumeration stacks = catchFlow.successors.elements(); |
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while (stacks.hasMoreElements()) { |
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Enumeration enum = ((Stack) stacks.nextElement()).elements(); |
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while (enum.hasMoreElements()) { |
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|
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Jump jump = (Jump) enum.nextElement(); |
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if (jump != null) { |
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jump.gen.mergeGenKill(gens, jump.kill); |
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} |
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} |
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} |
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tryFlow.in.unionExact(catchFlow.in); |
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tryFlow.gen.unionExact(catchFlow.gen); |
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|
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if (jode.Decompiler.debugInOut) { |
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System.err.println("UpdateInOutCatch: gens : "+gens); |
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System.err.println(" s.in : "+catchFlow.in); |
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System.err.println(" in : "+tryFlow.in); |
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} |
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} |
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|
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|
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/* simple try catch block: |
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* |
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* try-header |
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* |- first instruction |
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* | ... |
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* | last instruction |
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* |- optional jump (last+1) |
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* | ... |
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* `- catch block |
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*/ |
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static int serialno=0; |
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|
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static void analyzeCatchBlock(Type type, |
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FlowBlock tryFlow, FlowBlock catchFlow) { |
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|
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StructuredBlock catchBlock = catchFlow.block; |
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LocalInfo local = null; |
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StructuredBlock firstInstr = (catchBlock instanceof SequentialBlock) |
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? catchBlock.getSubBlocks()[0] : catchBlock; |
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|
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if (firstInstr instanceof InstructionBlock) { |
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Expression instr = |
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((InstructionBlock) firstInstr).getInstruction(); |
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if (instr instanceof PopOperator |
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&& ((PopOperator) instr).getCount() == 1) { |
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/* The exception is ignored. Create a dummy local for it */ |
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local = new LocalInfo(-1); |
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local.setName("exception_"+(serialno++)+"_"); |
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firstInstr.removeBlock(); |
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|
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} else if (instr instanceof jode.LocalStoreOperator) { |
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/* The exception is stored in a local variable */ |
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local = |
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((jode.LocalStoreOperator) instr).getLocalInfo(); |
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firstInstr.removeBlock(); |
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} |
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} |
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|
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if (local == null) { |
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local = new LocalInfo(-1); |
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local.setName("ERROR!!!"); |
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} |
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local.setType(type); |
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|
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CatchBlock newBlock = new CatchBlock(type, local); |
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((TryBlock)tryFlow.block).addCatchBlock(newBlock); |
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newBlock.setCatchBlock(catchFlow.block); |
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tryFlow.mergeSuccessors(catchFlow); |
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tryFlow.length += catchFlow.length; |
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} |
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|
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/* And now the complicated parts. */ |
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/** |
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* This transforms a sub routine, that is checks if the beginning |
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* local assignment matches the final ret and then returns. |
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*/ |
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boolean transformSubRoutine(FlowBlock subRoutine) { |
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try { |
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SequentialBlock sequBlock = (SequentialBlock) subRoutine.block; |
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LocalStoreOperator store = (LocalStoreOperator) |
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((InstructionBlock)sequBlock.subBlocks[0]).instr.getOperator(); |
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while (sequBlock.subBlocks[1] instanceof SequentialBlock) |
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sequBlock = (SequentialBlock) sequBlock.subBlocks[1]; |
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RetBlock retBlock = (RetBlock)sequBlock.subBlocks[1]; |
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if (! retBlock.local.equals(store.getLocalInfo())) |
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/* Ret doesn't match */ |
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return false; |
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subRoutine.block.getSubBlocks()[0].removeBlock(); |
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retBlock.removeBlock(); |
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return true; |
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} catch (ClassCastException ex) { |
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return false; |
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} |
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} |
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|
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/** |
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* Remove the JSR's jumping to the specified subRoutine. It |
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* is checked if the next block is a leaving instruction, and |
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* otherwise the JsrBlock is not removed (to give the user a |
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* hint that something went wrong). This will also remove the |
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* local javac generates for returns. |
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* @param tryFlow the FlowBLock of the try block. |
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* @param subRoutine the FlowBlock of the sub routine. |
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*/ |
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private void removeJSR(FlowBlock tryFlow, FlowBlock subRoutine) { |
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Stack jumps = (Stack)tryFlow.successors.remove(subRoutine); |
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if (jumps == null) |
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return; |
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Enumeration enum = jumps.elements(); |
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while (enum.hasMoreElements()) { |
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Jump jump = (Jump)enum.nextElement(); |
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|
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StructuredBlock prev = jump.prev; |
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prev.removeJump(); |
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if (prev instanceof EmptyBlock |
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&& prev.outer instanceof JsrBlock) { |
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if (prev.outer.getNextFlowBlock() != null) { |
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/* The jsr is directly before a jump, okay. */ |
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prev.outer.removeBlock(); |
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continue; |
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} |
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if (prev.outer.outer instanceof SequentialBlock |
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&& prev.outer.outer.getSubBlocks()[0] == prev.outer) { |
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SequentialBlock seq = (SequentialBlock) prev.outer.outer; |
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if (seq.subBlocks[1] instanceof JsrBlock) { |
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/* The jsr is followed by a jsr, okay. */ |
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prev.outer.removeBlock(); |
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continue; |
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} |
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if (seq.subBlocks[1] instanceof ReturnBlock |
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&& !(seq.subBlocks[1] instanceof ThrowBlock)) { |
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|
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/* The jsr is followed by a return, okay. */ |
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ReturnBlock ret = (ReturnBlock) seq.subBlocks[1]; |
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prev.outer.removeBlock(); |
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|
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if (ret.outer != null |
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&& ret.outer instanceof SequentialBlock) { |
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/* Try to eliminate the local that javac uses |
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* in this case. |
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*/ |
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try { |
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ComplexExpression expr = (ComplexExpression) |
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((InstructionBlock) |
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ret.outer.getSubBlocks()[0]).instr; |
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LocalStoreOperator store = |
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(LocalStoreOperator) expr.getOperator(); |
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if (store.matches((LocalLoadOperator) |
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ret.getInstruction())) { |
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ret.setInstruction(expr. |
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getSubExpressions()[0]); |
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ret.replace(ret.outer); |
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ret.used.removeElement |
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(store.getLocalInfo()); |
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} |
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} catch(ClassCastException ex) { |
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/* didn't succeed */ |
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} |
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} |
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continue; |
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} |
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} |
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} |
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/* Now we have a dangling JSR at the wrong place. |
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* We don't do anything, so that JSR will show up in |
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* the output. |
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*/ |
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} |
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} |
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|
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public void checkAndRemoveJSR(FlowBlock tryFlow, FlowBlock subRoutine) { |
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Enumeration keys = tryFlow.successors.keys(); |
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Enumeration stacks = tryFlow.successors.elements(); |
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while (keys.hasMoreElements()) { |
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Stack jumps = (Stack) stacks.nextElement(); |
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if (keys.nextElement() == subRoutine) |
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continue; |
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|
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Enumeration enum = jumps.elements(); |
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while (enum.hasMoreElements()) { |
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Jump jump = (Jump)enum.nextElement(); |
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|
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StructuredBlock prev = jump.prev; |
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if (prev instanceof ThrowBlock) { |
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/* The jump is a throw. We have a catch-all block |
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* that will do the finally. |
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*/ |
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continue; |
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} |
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if (prev instanceof JsrBlock) { |
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/* The jump is directly preceeded by a jsr. |
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* Everything okay. |
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*/ |
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continue; |
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} |
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|
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if (prev instanceof EmptyBlock |
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&& prev.outer instanceof JsrBlock) { |
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/* If jump is a jsr check the outer |
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* block instead. |
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*/ |
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prev = prev.outer; |
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} |
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if ((prev instanceof ReturnBlock |
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|| prev instanceof JsrBlock) |
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&& prev.outer instanceof SequentialBlock) { |
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SequentialBlock seq = (SequentialBlock) prev.outer; |
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if (seq.subBlocks[1] == prev |
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&& (seq.subBlocks[0] instanceof JsrBlock)) { |
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/* The jump is preceeded by another jsr, okay. |
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*/ |
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continue; |
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} |
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if (seq.subBlocks[0] == prev |
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&& seq.outer instanceof SequentialBlock |
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&& (seq.outer.getSubBlocks()[0] instanceof JsrBlock)) { |
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/* Again the jump is preceeded by another jsr, okay. |
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*/ |
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continue; |
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} |
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} |
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/* Now we have a jump with a wrong destination. |
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* Complain! |
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*/ |
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System.err.println("non well formed try-finally block"); |
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} |
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} |
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removeJSR(tryFlow, subRoutine); |
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} |
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|
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static boolean isMonitorExit(Expression instr, LocalInfo local) { |
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if (instr instanceof ComplexExpression) { |
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ComplexExpression expr = (ComplexExpression)instr; |
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if (expr.getOperator() instanceof MonitorExitOperator |
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&& expr.getSubExpressions()[0] instanceof LocalLoadOperator |
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&& (((LocalLoadOperator) expr.getSubExpressions()[0]) |
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.getLocalInfo().getSlot() == local.getSlot())) { |
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return true; |
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} |
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} |
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return false; |
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} |
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|
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public void checkAndRemoveMonitorExit(FlowBlock tryFlow, LocalInfo local, |
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int startMonExit, int endMonExit) { |
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FlowBlock subRoutine = null; |
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Enumeration stacks = tryFlow.successors.elements(); |
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dest_loop: |
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while (stacks.hasMoreElements()) { |
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Enumeration enum = ((Stack) stacks.nextElement()).elements(); |
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while (enum.hasMoreElements()) { |
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Jump jump = (Jump)enum.nextElement(); |
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|
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StructuredBlock prev = jump.prev; |
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if (prev instanceof EmptyBlock |
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&& prev.outer instanceof JsrBlock |
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&& subRoutine == null) { |
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|
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subRoutine = jump.destination; |
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subRoutine.analyze(startMonExit, endMonExit); |
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transformSubRoutine(subRoutine); |
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|
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if (subRoutine.block instanceof InstructionBlock) { |
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Expression instr = |
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((InstructionBlock)subRoutine.block) |
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.getInstruction(); |
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if (isMonitorExit(instr, local)) { |
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tryFlow.length += subRoutine.length; |
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continue dest_loop; |
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} |
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} |
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} |
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|
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if (prev instanceof ThrowBlock) { |
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/* The jump is a throw. We have a catch all block |
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* that will do the monitorexit. |
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*/ |
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continue; |
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} |
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if (prev instanceof JsrBlock) { |
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/* The jump is directly preceeded by a jsr. |
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*/ |
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continue; |
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} |
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if (prev instanceof EmptyBlock |
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&& prev.outer instanceof JsrBlock) { |
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/* If jump is a jsr check the outer |
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* block instead. |
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*/ |
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prev = prev.outer; |
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} |
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|
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if ((prev instanceof JsrBlock |
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|| prev instanceof ReturnBlock) |
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&& prev.outer instanceof SequentialBlock) { |
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SequentialBlock seq = (SequentialBlock) prev.outer; |
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StructuredBlock pred = null; |
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if (seq.subBlocks[1] == prev) |
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pred = seq.subBlocks[0]; |
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else if (seq.outer instanceof SequentialBlock) |
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pred = seq.outer.getSubBlocks()[0]; |
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|
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if (pred != null) { |
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if (pred instanceof JsrBlock || pred.jump != null) |
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/* The jump is preceeded by another jump |
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* or jsr and last in its block, okay. |
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*/ |
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continue; |
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|
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if (pred instanceof InstructionBlock) { |
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Expression instr = |
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((InstructionBlock)pred).getInstruction(); |
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if (instr instanceof ComplexExpression |
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&& ((ComplexExpression)instr) |
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.getOperator() instanceof MonitorExitOperator |
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&& ((ComplexExpression)instr) |
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.getSubExpressions()[0] |
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instanceof LocalLoadOperator |
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&& (((LocalLoadOperator) |
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((ComplexExpression)instr) |
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.getSubExpressions()[0]).getLocalInfo() |
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.getSlot() == local.getSlot())) |
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continue; |
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} |
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} |
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} |
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|
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if (prev instanceof InstructionBlock |
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&& isMonitorExit(((InstructionBlock)prev).instr, local)) { |
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/* This is probably the last expression in the |
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* synchronized block, and has the right monitor exit |
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* attached. Remove this block. |
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*/ |
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prev.removeBlock(); |
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continue; |
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} |
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|
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/* Now we have a jump that is not preceded by a monitorexit. |
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* Complain! |
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*/ |
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System.err.println("non well formed synchronized block"); |
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} |
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} |
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|
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if (subRoutine != null) |
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removeJSR(tryFlow, subRoutine); |
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} |
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|
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private boolean analyzeSynchronized(FlowBlock tryFlow, |
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FlowBlock catchFlow, |
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int endHandler) { |
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if (!(catchFlow.block instanceof SequentialBlock |
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&& catchFlow.block.getSubBlocks()[0] |
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instanceof InstructionBlock)) |
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return false; |
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|
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SequentialBlock catchBlock = (SequentialBlock) catchFlow.block; |
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Expression instr = |
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((InstructionBlock)catchBlock.subBlocks[0]).getInstruction(); |
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|
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if (instr instanceof ComplexExpression |
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&& ((ComplexExpression)instr).getOperator() |
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instanceof MonitorExitOperator |
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&& ((ComplexExpression)instr).getSubExpressions()[0] |
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instanceof LocalLoadOperator |
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&& catchBlock.subBlocks[1] instanceof ThrowBlock |
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&& ((ThrowBlock)catchBlock.subBlocks[1]).instr |
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instanceof NopOperator) { |
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|
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/* This is a synchronized block: |
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* |
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* local_x = monitor object; // later
|
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* monitorenter local_x // later
|
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* tryFlow: |
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* |- syncronized block |
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* | ... |
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* | every jump to outside is preceded by jsr subroutine-, |
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* | ... | |
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* |- monitorexit local_x | |
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* ` jump after this block (without jsr monexit) | |
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* | |
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* catchFlow: | |
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* local_n = stack | |
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* monitorexit local_x | |
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* throw local_n | |
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* oprtional subroutine: <----------------------------------' |
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* astore_n |
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* monitorexit local_x |
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* return_n |
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*/ |
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|
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/* Now remove the jump (after the throw) from the |
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* catch block so that we can forget about it. |
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*/ |
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|
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catchBlock.subBlocks[1] |
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.jump.destination.predecessors.removeElement(catchFlow); |
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|
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ComplexExpression monexit = (ComplexExpression) |
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((InstructionBlock) catchBlock.subBlocks[0]).instr; |
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LocalInfo local = |
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((LocalLoadOperator)monexit.getSubExpressions()[0]) |
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.getLocalInfo(); |
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tryFlow.length += catchFlow.length; |
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|
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checkAndRemoveMonitorExit |
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(tryFlow, local, catchFlow.addr+catchFlow.length, endHandler); |
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|
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SynchronizedBlock syncBlock = new SynchronizedBlock(local); |
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TryBlock tryBlock = (TryBlock) tryFlow.block; |
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syncBlock.replace(tryBlock); |
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syncBlock.moveJump(tryBlock.jump); |
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syncBlock.setBodyBlock(tryBlock.subBlocks.length == 1 |
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? tryBlock.subBlocks[0] : tryBlock); |
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tryFlow.lastModified = syncBlock; |
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return true; |
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} |
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return false; |
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} |
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|
||||
private boolean analyzeFinally(FlowBlock tryFlow, FlowBlock catchFlow, |
||||
int end) { |
||||
if (!(catchFlow.block instanceof SequentialBlock |
||||
&& catchFlow.block.getSubBlocks()[0] |
||||
instanceof InstructionBlock)) |
||||
return false; |
||||
|
||||
SequentialBlock catchBlock = (SequentialBlock) catchFlow.block; |
||||
Expression instr = |
||||
((InstructionBlock)catchBlock.subBlocks[0]).getInstruction(); |
||||
|
||||
if (catchBlock.subBlocks[1] instanceof SequentialBlock |
||||
&& catchBlock.subBlocks[1].getSubBlocks()[0] |
||||
instanceof JsrBlock |
||||
&& instr instanceof LocalStoreOperator |
||||
&& catchBlock.subBlocks[1].getSubBlocks()[1] |
||||
instanceof ThrowBlock |
||||
&& ((ThrowBlock)catchBlock.subBlocks[1] |
||||
.getSubBlocks()[1]).instr |
||||
instanceof LocalLoadOperator |
||||
&& ((LocalStoreOperator) instr) |
||||
.matches((LocalLoadOperator) |
||||
((ThrowBlock)catchBlock.subBlocks[1] |
||||
.getSubBlocks()[1]).instr)) { |
||||
|
||||
/* Wow that was complicated :-) |
||||
* But now we know that the catch block looks |
||||
* exactly like an try finally block: |
||||
* |
||||
* tryFlow: |
||||
* |- first instruction |
||||
* | ... |
||||
* | every jump to outside is preceded by jsr finally |
||||
* | ... |
||||
* | jsr finally -----------------, |
||||
* `- jump after finally | |
||||
* | |
||||
* catchFlow: (already checked) | |
||||
* local_n = stack v |
||||
* jsr finally ---------------->| |
||||
* throw local_n; | |
||||
* finally: <-----------------------' |
||||
* astore_n |
||||
* ... |
||||
* return_n |
||||
*/ |
||||
|
||||
FlowBlock subRoutine = |
||||
((JsrBlock)catchBlock.subBlocks[1].getSubBlocks()[0]) |
||||
.innerBlock.jump.destination; |
||||
|
||||
/* Now remove the two jumps of the catch block |
||||
* so that we can forget about them. |
||||
* This are the jsr and the throw. |
||||
*/ |
||||
catchBlock.subBlocks[1].getSubBlocks()[0].getSubBlocks()[0] |
||||
.jump.destination.predecessors.removeElement(catchFlow); |
||||
catchBlock.subBlocks[1].getSubBlocks()[1] |
||||
.jump.destination.predecessors.removeElement(catchFlow); |
||||
|
||||
subRoutine.analyze(catchFlow.addr+catchFlow.length, end); |
||||
if (!transformSubRoutine(subRoutine)) |
||||
return false; |
||||
Stack jumps = (Stack)tryFlow.successors.get(subRoutine); |
||||
if (jumps != null) |
||||
/* jumps may be null, if tryFlow ends with a throw */ |
||||
tryFlow.updateInOut(subRoutine, true, jumps); |
||||
|
||||
tryFlow.length += catchFlow.length; |
||||
checkAndRemoveJSR(tryFlow, subRoutine); |
||||
|
||||
TryBlock tryBlock = (TryBlock)tryFlow.block; |
||||
if (tryBlock.getSubBlocks()[0] instanceof TryBlock) { |
||||
/* remove the nested tryBlock */ |
||||
TryBlock innerTry = (TryBlock)tryBlock.getSubBlocks()[0]; |
||||
innerTry.gen = tryBlock.gen; |
||||
innerTry.replace(tryBlock); |
||||
tryBlock = innerTry; |
||||
tryFlow.lastModified = innerTry; |
||||
} |
||||
FinallyBlock newBlock = new FinallyBlock(); |
||||
newBlock.setCatchBlock(subRoutine.block); |
||||
tryBlock.addCatchBlock(newBlock); |
||||
tryFlow.mergeSuccessors(subRoutine); |
||||
tryFlow.length += subRoutine.length; |
||||
return true; |
||||
} |
||||
return false; |
||||
} |
||||
|
||||
private boolean analyzeSpecialFinally(FlowBlock tryFlow, |
||||
FlowBlock catchFlow, int end) { |
||||
|
||||
StructuredBlock firstInstr = |
||||
catchFlow.block instanceof SequentialBlock |
||||
? catchFlow.block.getSubBlocks()[0]: catchFlow.block; |
||||
|
||||
if (firstInstr instanceof InstructionBlock |
||||
&& ((InstructionBlock) firstInstr).getInstruction() |
||||
instanceof PopOperator |
||||
&& ((PopOperator) ((InstructionBlock) firstInstr) |
||||
.getInstruction()).getCount() == 1) { |
||||
|
||||
/* This is a special try/finally-block, where |
||||
* the finally block ends with a break, return or |
||||
* similar. |
||||
*/ |
||||
|
||||
FlowBlock succ = (firstInstr.jump != null) ? |
||||
firstInstr.jump.destination : null; |
||||
boolean hasExit = false; |
||||
Enumeration keys = tryFlow.successors.keys(); |
||||
while (keys.hasMoreElements()) { |
||||
Object key = keys.nextElement(); |
||||
if (key == succ) |
||||
continue; |
||||
if (key != tryFlow.END_OF_METHOD) { |
||||
/* There is another exit in the try block, bad */ |
||||
return false; |
||||
} |
||||
Enumeration enum = |
||||
((Stack)tryFlow.successors.get(key)).elements(); |
||||
while (enum.hasMoreElements()) { |
||||
Jump throwJump= (Jump)enum.nextElement(); |
||||
if (!(throwJump.prev instanceof ThrowBlock)) { |
||||
/* There is a return exit in the try block */ |
||||
return false; |
||||
} |
||||
} |
||||
} |
||||
|
||||
/* remove the pop now */ |
||||
firstInstr.removeBlock(); |
||||
|
||||
if (succ != null) { |
||||
Stack jumps = (Stack) tryFlow.successors.remove(succ); |
||||
succ.predecessors.removeElement(tryFlow); |
||||
/* Handle the jumps in the tryFlow. |
||||
*/ |
||||
tryFlow.updateInOut(succ, true, jumps); |
||||
tryFlow.optimizeJumps(jumps, succ); |
||||
tryFlow.resolveRemaining(jumps); |
||||
} |
||||
|
||||
tryFlow.length += catchFlow.length; |
||||
|
||||
TryBlock tryBlock = (TryBlock)tryFlow.block; |
||||
if (tryBlock.getSubBlocks()[0] instanceof TryBlock) { |
||||
/* remove the unnecessary tryBlock */ |
||||
TryBlock innerTry = (TryBlock)tryBlock.getSubBlocks()[0]; |
||||
innerTry.gen = tryBlock.gen; |
||||
innerTry.replace(tryBlock); |
||||
tryBlock = innerTry; |
||||
tryFlow.lastModified = innerTry; |
||||
} |
||||
FinallyBlock newBlock = new FinallyBlock(); |
||||
tryBlock.addCatchBlock(newBlock); |
||||
/* try block has no successors */ |
||||
|
||||
if (succ != null && succ.predecessors.size() == 1) { |
||||
while (succ.analyze(catchFlow.addr+catchFlow.length, end)); |
||||
tryFlow.length += succ.length; |
||||
tryFlow.successors.remove(succ); |
||||
newBlock.setCatchBlock(succ.block); |
||||
tryFlow.mergeSuccessors(succ); |
||||
} else { |
||||
/* Put the catchBlock in instaed. |
||||
*/ |
||||
newBlock.setCatchBlock(catchFlow.block); |
||||
tryFlow.mergeSuccessors(catchFlow); |
||||
} |
||||
return true; |
||||
} |
||||
return false; |
||||
} |
||||
|
||||
/** |
||||
* Analyzes all exception handlers to try/catch/finally or |
||||
* synchronized blocks. |
||||
*/ |
||||
public void analyze() { |
||||
/* Check if try/catch ranges are okay. The following succeeds |
||||
* for all classes generated by the sun java compiler, but hand |
||||
* optimized classes will fail this. |
||||
*/ |
||||
for (int i=0; i<count; i++) { |
||||
int start = startPCs[i]; |
||||
int end = endPCs[i]; |
||||
int handler = handlerPCs[i]; |
||||
if (start >= end || handler < end) |
||||
throw new AssertError("ExceptionHandler order failed: not " |
||||
+ start + " < " + end + " <= " + |
||||
handler); |
||||
if (i == 0 |
||||
|| startPCs[i-1] != start || endPCs[i-1] != end) { |
||||
/* The last handler does catch another range. */ |
||||
if ( /*handler > end + 1 || */ |
||||
(i > 0 && end > startPCs[i-1] && end < endPCs[i-1])) |
||||
throw new AssertError("ExceptionHandler" |
||||
+ " at wrong position: " |
||||
+ "end: "+end + " handler: "+handler |
||||
+ (i>0 ? " last: ("+startPCs[i-1] |
||||
+", "+endPCs[i-1]+", " |
||||
+handlerPCs[i-1]+")" |
||||
:"")); |
||||
} |
||||
} |
||||
|
||||
for (int i=0; i<count; i++) { |
||||
int endHandler = (i< count-1 && endPCs[i+1] > handlerPCs[i]) |
||||
? endPCs[i+1] |
||||
: Integer.MAX_VALUE; |
||||
if (jode.Decompiler.debugAnalyze) |
||||
System.err.println("analyzeCatch(" + startPCs[i] + ", " |
||||
+ endPCs[i] + ", " +handlerPCs[i] + ")"); |
||||
FlowBlock tryFlow = flows[startPCs[i]]; |
||||
while (tryFlow.analyze(startPCs[i], handlerPCs[i])); |
||||
|
||||
if (i == 0 |
||||
|| startPCs[i-1] != startPCs[i] || endPCs[i-1] != endPCs[i]) { |
||||
/* The last handler does catch another range. |
||||
* Create a new try block. |
||||
*/ |
||||
TryBlock tryBlock = new TryBlock(tryFlow); |
||||
} else if (! (tryFlow.block instanceof TryBlock)) |
||||
throw new AssertError("no TryBlock"); |
||||
|
||||
FlowBlock catchFlow = flows[handlerPCs[i]]; |
||||
while (catchFlow.analyze(handlerPCs[i], endHandler)); |
||||
|
||||
if (!catchFlow.predecessors.isEmpty()) |
||||
throw new AssertError("Handler has a predecessors"); |
||||
|
||||
updateInOutCatch(tryFlow, catchFlow); |
||||
if (types[i] != null) { |
||||
analyzeCatchBlock(types[i], tryFlow, catchFlow); |
||||
|
||||
} else if (!analyzeSynchronized(tryFlow, catchFlow, endHandler) |
||||
&& ! analyzeFinally(tryFlow, catchFlow, endHandler) |
||||
&& ! analyzeSpecialFinally(tryFlow, catchFlow, |
||||
endHandler)) |
||||
|
||||
analyzeCatchBlock(jode.Type.tObject, tryFlow, catchFlow); |
||||
|
||||
tryFlow.checkConsistent(); |
||||
if (jode.Decompiler.debugAnalyze) |
||||
System.err.println("analyzeCatch(" + tryFlow.addr + ", " |
||||
+ (tryFlow.addr + tryFlow.length) + |
||||
") done."); |
||||
} |
||||
} |
||||
} |
||||
@ -0,0 +1,103 @@ |
||||
/* jode.flow.TryBlock (c) 1998 Jochen Hoenicke |
||||
* |
||||
* You may distribute under the terms of the GNU General Public License. |
||||
* |
||||
* IN NO EVENT SHALL JOCHEN HOENICKE BE LIABLE TO ANY PARTY FOR DIRECT, |
||||
* INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF |
||||
* THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF JOCHEN HOENICKE |
||||
* HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
* |
||||
* JOCHEN HOENICKE SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT |
||||
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A |
||||
* PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS" |
||||
* BASIS, AND JOCHEN HOENICKE HAS NO OBLIGATION TO PROVIDE MAINTENANCE, |
||||
* SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. |
||||
* |
||||
* $Id$ |
||||
*/ |
||||
|
||||
package jode.flow; |
||||
import jode.TabbedPrintWriter; |
||||
|
||||
/** |
||||
* A TryBlock is created for each exception in the |
||||
* ExceptionHandlers-Attribute. <p> |
||||
* |
||||
* For each catch block (there may be more than one catch block |
||||
* appending a single try block) and for each finally and each |
||||
* synchronized block such a TryBlock is created. The |
||||
* finally/synchronized-blocks have a null exception type so that they |
||||
* are easily distinguishable from the catch blocks. <p> |
||||
* |
||||
* A TryBlock is an intermediate representation that gets |
||||
* converted later to a CatchBlock, a FinallyBlock or a |
||||
* SynchronizedBlock (after the body is parsed). |
||||
* |
||||
* @date 1998/09/16 |
||||
* @author Jochen Hoenicke |
||||
* @see CatchBlock |
||||
* @see FinallyBlock |
||||
* @see SynchronizedBlock |
||||
*/ |
||||
|
||||
public class TryBlock extends StructuredBlock { |
||||
|
||||
VariableSet gen; |
||||
StructuredBlock[] subBlocks = new StructuredBlock[1]; |
||||
|
||||
public TryBlock(FlowBlock tryFlow) { |
||||
this.gen = (VariableSet) tryFlow.gen.clone(); |
||||
this.flowBlock = tryFlow; |
||||
|
||||
StructuredBlock bodyBlock = tryFlow.block; |
||||
replace(bodyBlock); |
||||
this.subBlocks = new StructuredBlock[] { bodyBlock }; |
||||
bodyBlock.outer = this; |
||||
tryFlow.lastModified = this; |
||||
} |
||||
|
||||
public void addCatchBlock(CatchBlock catchBlock) { |
||||
StructuredBlock[] newSubBlocks = |
||||
new StructuredBlock[subBlocks.length+1]; |
||||
System.arraycopy(subBlocks, 0, newSubBlocks, 0, subBlocks.length); |
||||
newSubBlocks[subBlocks.length] = catchBlock; |
||||
subBlocks = newSubBlocks; |
||||
catchBlock.outer = this; |
||||
catchBlock.setFlowBlock(flowBlock); |
||||
} |
||||
|
||||
/** |
||||
* Replaces the given sub block with a new block. |
||||
* @param oldBlock the old sub block. |
||||
* @param newBlock the new sub block. |
||||
* @return false, if oldBlock wasn't a direct sub block. |
||||
*/ |
||||
public boolean replaceSubBlock(StructuredBlock oldBlock, |
||||
StructuredBlock newBlock) { |
||||
for (int i=0; i<subBlocks.length; i++) { |
||||
if (subBlocks[i] == oldBlock) { |
||||
subBlocks[i] = newBlock; |
||||
return true; |
||||
} |
||||
} |
||||
return false; |
||||
} |
||||
|
||||
/** |
||||
* Returns all sub block of this structured block. |
||||
*/ |
||||
public StructuredBlock[] getSubBlocks() { |
||||
return subBlocks; |
||||
} |
||||
|
||||
public void dumpInstruction(TabbedPrintWriter writer) |
||||
throws java.io.IOException { |
||||
writer.println("try {"); |
||||
writer.tab(); |
||||
subBlocks[0].dumpSource(writer); |
||||
writer.untab(); |
||||
for (int i=1; i<subBlocks.length;i++) |
||||
subBlocks[i].dumpSource(writer); |
||||
writer.println("}"); |
||||
} |
||||
} |
||||
Loading…
Reference in new issue