Fixed: #2270 AS3 decompilation - unnnecessary local registers assignments as part of expressions when using optimization like dup, setlocal N instead of setlocal N, getlocal N

libsrc/ffdec_lib/src/com/jpexs/decompiler/graph/AbstractGraphTargetRecursiveVisitor.java

@@ -0,0 +1,44 @@
+/*
+ *  Copyright (C) 2010-2024 JPEXS, All rights reserved.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3.0 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library.
+ */
+package com.jpexs.decompiler.graph;
+
+import java.util.Collection;
+import java.util.Stack;
+
+/**
+ * Abstract graph target recursive visitor.
+ *
+ * @author JPEXS
+ */
+public abstract class AbstractGraphTargetRecursiveVisitor implements GraphTargetRecursiveVisitorInterface {
+
+    /**
+     * Constructs new AbstractGraphTargetVisitor
+     */
+    public AbstractGraphTargetRecursiveVisitor() {
+    }
+
+    @Override
+    public abstract void visit(GraphTargetItem item, Stack<GraphTargetItem> parentStack);
+
+    @Override
+    public final void visitAll(Collection<GraphTargetItem> items, Stack<GraphTargetItem> parentStack) {
+        for (GraphTargetItem item : items) {
+            visit(item, parentStack);
+        }
+    }
+}

libsrc/ffdec_lib/src/com/jpexs/decompiler/graph/Graph.java

@@ -2715,6 +2715,18 @@ public class Graph {
         return printGraph(foundGotos, partCodes, partCodePos, visited, localData, stack, allParts, parent, part, stopPart, stopPartKind, loops, throwStates, null, staticOperation, path, 0);
     }
 
+    /**
+     * Gets if expression from stack.
+     * Can be overriden for custom handling
+     * @param localData Local data
+     * @param stack Stack
+     * @param output Output
+     * @return Expression
+     */
+    protected GraphTargetItem getIfExpression(BaseLocalData localData, TranslateStack stack, List<GraphTargetItem> output) {
+        return stack.pop();
+    }
+    
     /**
      * Walks graph parts and converts them to target items.
      *
@@ -3254,7 +3266,7 @@ public class Graph {
                 } //else
                 GraphPart nextOnePart = null;
                 if (getNextParts(localData, part).size() == 2 && !partIsSwitch(part)) {
-                    GraphTargetItem expr = stack.pop();
+                    GraphTargetItem expr = getIfExpression(localData, stack, currentRet);
 
                     if (nextOnePart == null) {
 

libsrc/ffdec_lib/src/com/jpexs/decompiler/graph/GraphTargetItem.java

@@ -48,6 +48,7 @@ import java.util.Arrays;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
+import java.util.Stack;
 
 /**
  * Graph target item - an item in high level representation of the code.
@@ -963,15 +964,19 @@ public abstract class GraphTargetItem implements Serializable, Cloneable {
      *
      * @param visitor Visitor
      */
-    public final void visitRecursivelyNoBlock(GraphTargetVisitorInterface visitor) {
+    public final void visitRecursivelyNoBlock(GraphTargetRecursiveVisitorInterface visitor) {
         Set<GraphTargetItem> visitedItems = new HashSet<>();
+        Stack<GraphTargetItem> parentStack = new Stack<>();
+        parentStack.add(this);
         visitNoBlock(new AbstractGraphTargetVisitor() {
             @Override
             public void visit(GraphTargetItem item) {
                 if (item != null && !visitedItems.contains(item)) {
                     visitedItems.add(item);
-                    visitor.visit(item);
+                    visitor.visit(item, parentStack);
+                    parentStack.push(item);
                     item.visitNoBlock(this);
+                    parentStack.pop();
                 }
             }
         });

libsrc/ffdec_lib/src/com/jpexs/decompiler/graph/GraphTargetRecursiveVisitorInterface.java

@@ -0,0 +1,44 @@
+/*
+ *  Copyright (C) 2010-2024 JPEXS, All rights reserved.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3.0 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library.
+ */
+package com.jpexs.decompiler.graph;
+
+import java.util.Collection;
+import java.util.Stack;
+
+/**
+ * Recursive graph target visitor interface.
+ *
+ * @author JPEXS
+ */
+public interface GraphTargetRecursiveVisitorInterface {
+
+    /**
+     * Visits a graph target item.
+     *
+     * @param item Graph target item
+     * @param parentStack Stack of parents
+     */
+    public void visit(GraphTargetItem item, Stack<GraphTargetItem> parentStack);
+
+    /**
+     * Visits all graph target items.
+     *
+     * @param items Collection of graph target items
+     * @param parentStack Stack of parents
+     */
+    public void visitAll(Collection<GraphTargetItem> items, Stack<GraphTargetItem> parentStack);
+}

libsrc/ffdec_lib/src/com/jpexs/decompiler/graph/GraphTargetVisitorInterface.java

@@ -19,7 +19,7 @@ package com.jpexs.decompiler.graph;
 import java.util.Collection;
 
 /**
- * Graph source visitor interface.
+ * Graph target visitor interface.
  *
  * @author JPEXS
  */

libsrc/ffdec_lib/src/com/jpexs/decompiler/graph/TranslateStack.java

@@ -17,6 +17,10 @@
 package com.jpexs.decompiler.graph;
 
 import com.jpexs.decompiler.graph.model.PopItem;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
 import java.util.Stack;
 import java.util.logging.Level;
 import java.util.logging.Logger;
@@ -38,6 +42,27 @@ public class TranslateStack extends Stack<GraphTargetItem> {
      */
     private final String path;
 
+    private Map<String, GraphTargetItem> marks = new HashMap<>();
+
+    
+    /**
+     * Sets mark.
+     * @param name Name
+     * @param value Value
+     */
+    public void setMark(String name, GraphTargetItem value) {
+        marks.put(name, value);
+    }
+    
+    /**
+     * Gets mark.
+     * @param name Name
+     * @return Value
+     */
+    public GraphTargetItem getMark(String name) {
+        return marks.get(name);
+    }
+    
     /**
      * Simplifies all items in the stack.
      */