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diff --git a/src/proguard/optimize/info/SideEffectMethodMarker.java b/src/proguard/optimize/info/SideEffectMethodMarker.java
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+++ b/src/proguard/optimize/info/SideEffectMethodMarker.java
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+/*
+ * ProGuard -- shrinking, optimization, obfuscation, and preverification
+ *             of Java bytecode.
+ *
+ * Copyright (c) 2002-2009 Eric Lafortune (eric@graphics.cornell.edu)
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program 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 for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+package proguard.optimize.info;
+
+import proguard.classfile.*;
+import proguard.classfile.attribute.*;
+import proguard.classfile.attribute.visitor.AttributeVisitor;
+import proguard.classfile.instruction.*;
+import proguard.classfile.util.SimplifiedVisitor;
+import proguard.classfile.visitor.*;
+
+/**
+ * This ClassPoolVisitor marks all methods that have side effects.
+ *
+ * @see ReadWriteFieldMarker
+ * @see NoSideEffectMethodMarker
+ * @author Eric Lafortune
+ */
+public class SideEffectMethodMarker
+extends      SimplifiedVisitor
+implements   ClassPoolVisitor,
+             ClassVisitor,
+             MemberVisitor,
+             AttributeVisitor
+{
+    // A reusable object for checking whether instructions have side effects.
+    private final SideEffectInstructionChecker sideEffectInstructionChecker = new SideEffectInstructionChecker(false);
+
+    // Parameters and values for visitor methods.
+    private int     newSideEffectCount;
+    private boolean hasSideEffects;
+
+
+    // Implementations for ClassPoolVisitor.
+
+    public void visitClassPool(ClassPool classPool)
+    {
+        // Go over all classes and their methods, marking if they have side
+        // effects, until no new cases can be found.
+        do
+        {
+            newSideEffectCount = 0;
+
+            // Go over all classes and their methods once.
+            classPool.classesAccept(this);
+        }
+        while (newSideEffectCount > 0);
+    }
+
+
+    // Implementations for ClassVisitor.
+
+    public void visitProgramClass(ProgramClass programClass)
+    {
+        // Go over all methods.
+        programClass.methodsAccept(this);
+    }
+
+
+    // Implementations for MemberVisitor.
+
+    public void visitProgramMethod(ProgramClass programClass, ProgramMethod programMethod)
+    {
+        if (!hasSideEffects(programMethod) &&
+            !NoSideEffectMethodMarker.hasNoSideEffects(programMethod))
+        {
+            // Initialize the return value.
+            hasSideEffects =
+                (programMethod.getAccessFlags() &
+                 (ClassConstants.INTERNAL_ACC_NATIVE |
+                  ClassConstants.INTERNAL_ACC_SYNCHRONIZED)) != 0;
+
+            // Look further if the method hasn't been marked yet.
+            if (!hasSideEffects)
+            {
+                // Investigate the actual code.
+                programMethod.attributesAccept(programClass, this);
+            }
+
+            // Mark the method depending on the return value.
+            if (hasSideEffects)
+            {
+                markSideEffects(programMethod);
+
+                newSideEffectCount++;
+            }
+        }
+    }
+
+
+    // Implementations for AttributeVisitor.
+
+    public void visitAnyAttribute(Clazz clazz, Attribute attribute) {}
+
+
+    public void visitCodeAttribute(Clazz clazz, Method method, CodeAttribute codeAttribute)
+    {
+        // Remember whether the code has any side effects.
+        hasSideEffects = hasSideEffects(clazz, method, codeAttribute);
+    }
+
+
+    // Small utility methods.
+
+    /**
+     * Returns whether the given code has any side effects.
+     */
+    private boolean hasSideEffects(Clazz         clazz,
+                                   Method        method,
+                                   CodeAttribute codeAttribute)
+    {
+        byte[] code   = codeAttribute.code;
+        int    length = codeAttribute.u4codeLength;
+
+        // Go over all instructions.
+        int offset = 0;
+        do
+        {
+            // Get the current instruction.
+            Instruction instruction = InstructionFactory.create(code, offset);
+
+            // Check if it may be throwing exceptions.
+            if (sideEffectInstructionChecker.hasSideEffects(clazz,
+                                                            method,
+                                                            codeAttribute,
+                                                            offset,
+                                                            instruction))
+            {
+                return true;
+            }
+
+            // Go to the next instruction.
+            offset += instruction.length(offset);
+        }
+        while (offset < length);
+
+        return false;
+    }
+
+
+    private static void markSideEffects(Method method)
+    {
+        MethodOptimizationInfo info = MethodOptimizationInfo.getMethodOptimizationInfo(method);
+        if (info != null)
+        {
+            info.setSideEffects();
+        }
+    }
+
+
+    public static boolean hasSideEffects(Method method)
+    {
+        MethodOptimizationInfo info = MethodOptimizationInfo.getMethodOptimizationInfo(method);
+        return info == null ||
+               info.hasSideEffects();
+    }
+}