diff --git a/src/de/inetsoftware/jwebassembly/module/BranchManger.java b/src/de/inetsoftware/jwebassembly/module/BranchManger.java
index 221497c..d78d358 100644
--- a/src/de/inetsoftware/jwebassembly/module/BranchManger.java
+++ b/src/de/inetsoftware/jwebassembly/module/BranchManger.java
@@ -73,8 +73,8 @@ class BranchManger {
      *            the values of the cases
      * @param positions
      *            the code positions
-     * @param the
-     *            code position of the default block
+     * @param defaultPosition
+     *            the code position of the default block
      */
     void startSwitch( int startPosition, int offset, int lineNumber, int[] keys, int[] positions, int defaultPosition ) {
         allParsedOperations.add( new SwitchParsedBlock( startPosition, offset, lineNumber, keys, positions, defaultPosition ) );
@@ -209,7 +209,7 @@ class BranchManger {
      *            the not consumed operations in the parent branch
      */
     private void caculateSwitch( BranchNode parent, SwitchParsedBlock switchBlock, List<ParsedBlock> parsedOperations ) {
-        int startPosition = switchBlock.startPosition;
+        int startPosition = ((ParsedBlock)switchBlock).startPosition;
         int posCount = switchBlock.positions.length;
         boolean isTable = switchBlock.keys.length == 1;
         if( isTable ) { 
@@ -228,13 +228,16 @@ class BranchManger {
             Arrays.sort( cases, (a, b) -> Integer.compare( a.position, b.position ) );
             int blockCount = 0;
             int lastPosition = -1;
-            BranchNode brTableNode = new BranchNode( startPosition, startPosition, WasmBlockOperator.BR_TABLE, null );
-            BranchNode blockNode = brTableNode;
+            BranchNode brTableNode = null;
+            BranchNode blockNode = null;
             for( int i = 0; i < cases.length; i++ ) {
                 switchCase = cases[i];
                 switchCase.block = blockCount;
                 int currentPosition = switchCase.position;
                 if( lastPosition != currentPosition ) {
+                    if( blockNode == null ) {
+                        blockNode = brTableNode = new BranchNode( currentPosition, currentPosition, WasmBlockOperator.BR_TABLE, null );
+                    }
                     lastPosition = currentPosition;
                     blockCount++;
                     BranchNode node = new BranchNode( startPosition, startPosition + currentPosition, WasmBlockOperator.BLOCK, WasmBlockOperator.END );
@@ -303,9 +306,9 @@ class BranchManger {
     private static class ParsedBlock {
         private JavaBlockOperator op;
 
-        int                       startPosition;
+        private int               startPosition;
 
-        int                       endPosition;
+        private int               endPosition;
 
         private int               lineNumber;
 
diff --git a/src/de/inetsoftware/jwebassembly/module/ModuleWriter.java b/src/de/inetsoftware/jwebassembly/module/ModuleWriter.java
index 3e148b6..d4dafa6 100644
--- a/src/de/inetsoftware/jwebassembly/module/ModuleWriter.java
+++ b/src/de/inetsoftware/jwebassembly/module/ModuleWriter.java
@@ -53,6 +53,8 @@ public abstract class ModuleWriter implements Closeable {
 
     private BranchManger         branchManager = new BranchManger();
 
+    private ValueStackManger     stackManager = new ValueStackManger();
+
     /**
      * Prepare the content of the class.
      * 
@@ -133,6 +135,7 @@ public abstract class ModuleWriter implements Closeable {
                 locals.clear();
                 localTable = code.getLocalVariableTable();
 
+                stackManager.reset();
                 branchManager.reset();
                 for( CodeInputStream byteCode : code.getByteCodes() ) {
                     prepareBranchManager( byteCode, lineNumber = byteCode.getLineNumber() );
@@ -296,12 +299,30 @@ public abstract class ModuleWriter implements Closeable {
             while( byteCode.available() > 0 ) {
                 int op = byteCode.readUnsignedByte();
                 switch( op ) {
+                    case 21: // iload
+                        stackManager.add( ValueType.i32, byteCode.getCodePosition() - 1 );
+                        byteCode.skip(1);
+                        break;
+                    case 22: // lload
+                        stackManager.add( ValueType.i64, byteCode.getCodePosition() - 1 );
+                        byteCode.skip(1);
+                        break;
+                    case 23: // fload
+                        stackManager.add( ValueType.f32, byteCode.getCodePosition() - 1 );
+                        byteCode.skip(1);
+                        break;
+                    case 24: // dload
+                        stackManager.add( ValueType.f64, byteCode.getCodePosition() - 1 );
+                        byteCode.skip(1);
+                        break;
+                    case 26: // iload_0
+                    case 27: // iload_1
+                    case 28: // iload_2
+                    case 29: // iload_3
+                        stackManager.add( ValueType.i32, byteCode.getCodePosition() - 1 );
+                        break;
                     case 16: // bipush
                     case 18: // ldc
-                    case 21: //iload
-                    case 22: //lload
-                    case 23: //fload
-                    case 24: //dload
                     case 25: //aload
                     case 54: // istore
                     case 55: // lstore
@@ -351,7 +372,7 @@ public abstract class ModuleWriter implements Closeable {
                         }
                         startPosition--;
 
-                        int defaultPosition = offset = byteCode.readInt();
+                        int defaultPosition = startPosition + byteCode.readInt();
                         int[] keys;
                         int[] positions;
                         if( op == 171 ) { // lookupswitch
@@ -360,7 +381,7 @@ public abstract class ModuleWriter implements Closeable {
                             positions = new int[nPairs];
                             for( int i = 0; i < nPairs; i++ ) {
                                 keys[i] = byteCode.readInt();
-                                offset = Math.max( offset, positions[i] = byteCode.readInt() );
+                                positions[i] = startPosition + byteCode.readInt();
                             }
                         } else {
                             int low = byteCode.readInt();
@@ -368,10 +389,11 @@ public abstract class ModuleWriter implements Closeable {
                             int count = byteCode.readInt() - low + 1;
                             positions = new int[count];
                             for( int i = 0; i < count; i++ ) {
-                                offset = Math.max( offset, positions[i] = byteCode.readInt() );
+                                positions[i] = startPosition + byteCode.readInt();
                             }
                         }
-                        branchManager.startSwitch( startPosition, offset, lineNumber, keys, positions, defaultPosition );
+                        int switchValuestartPosition = stackManager.getCodePosition( 0 );
+                        branchManager.startSwitch( switchValuestartPosition, 0, lineNumber, keys, positions, defaultPosition );
                         break;
                 }
             }