write local method names if DebugNames is enabled

src/de/inetsoftware/jwebassembly/binary/BinaryModuleWriter.java

@@ -62,7 +62,7 @@ public class BinaryModuleWriter extends ModuleWriter implements InstructionOpcod
 
     private Map<String, Function>       functions           = new LinkedHashMap<>();
 
-    private List<ValueType>             locals;
+    private List<ValueType>             locals              = new ArrayList<>();
 
     private Map<String, Global>         globals             = new LinkedHashMap<>();
 
@@ -197,6 +197,24 @@ public class BinaryModuleWriter extends ModuleWriter implements InstructionOpcod
         stream.writeVaruint32( section.size() );
         section.writeTo( stream );
 
+        // write function parameter names
+        stream.write( 2 ); // 2 - Local names
+        section.reset();
+        section.writeVaruint32( functions.size() );
+        for( Entry<String, Function> entry : functions.entrySet() ) {
+            Function func = entry.getValue();
+            section.writeVaruint32( func.id ); // function index
+            List<String> paramNames = func.paramNames;
+            int count = paramNames == null ? 0 : paramNames.size();
+            section.writeVaruint32( count ); // count of locals
+            for( int i = 0; i < count; i++ ) {
+                section.writeVaruint32( i );
+                section.writeString( paramNames.get( i ) );
+            }
+        }
+        stream.writeVaruint32( section.size() );
+        section.writeTo( stream );
+
         wasm.writeSection( SectionType.Custom, stream );
     }
 
@@ -251,20 +269,30 @@ public class BinaryModuleWriter extends ModuleWriter implements InstructionOpcod
         function = functions.get( name.signatureName );
         functionType = new FunctionType();
         codeStream.reset();
+        locals.clear();
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
-    protected void writeMethodParam( String kind, ValueType valueType ) throws IOException {
+    protected void writeMethodParam( String kind, ValueType valueType, @Nullable String name ) throws IOException {
         switch( kind ) {
             case "param":
                 functionType.params.add( valueType );
-                return;
+                break;
             case "result":
                 functionType.result = valueType;
                 return;
+            case "local":
+                locals.add( valueType );
+                break;
+        }
+        if( debugNames && name != null ) {
+            if( function.paramNames == null ) {
+                function.paramNames = new ArrayList<>();
+            }
+            function.paramNames.add( name );
         }
     }
 
@@ -272,14 +300,13 @@ public class BinaryModuleWriter extends ModuleWriter implements InstructionOpcod
      * {@inheritDoc}
      */
     @Override
-    protected void writeMethodParamFinish( List<ValueType> locals ) throws IOException {
+    protected void writeMethodParamFinish() throws IOException {
         int typeId = functionTypes.indexOf( functionType );
         if( typeId < 0 ) {
             typeId = functionTypes.size();
             functionTypes.add( functionType );
         }
         function.typeId = typeId;
-        this.locals = locals;
     }
 
     /**

src/de/inetsoftware/jwebassembly/binary/Function.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 Volker Berlin (i-net software)
+ * Copyright 2017 - 2018 Volker Berlin (i-net software)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,6 +16,7 @@
 package de.inetsoftware.jwebassembly.binary;
 
 import java.io.IOException;
+import java.util.List;
 
 /**
  * An entry in the function section of the WebAssembly.
@@ -28,6 +29,8 @@ class Function extends SectionEntry {
 
     int typeId;
 
+    List<String> paramNames;
+
     /**
      * {@inheritDoc}
      */

src/de/inetsoftware/jwebassembly/module/ModuleGenerator.java

@@ -29,6 +29,7 @@ import de.inetsoftware.classparser.Code;
 import de.inetsoftware.classparser.CodeInputStream;
 import de.inetsoftware.classparser.ConstantPool;
 import de.inetsoftware.classparser.ConstantRef;
+import de.inetsoftware.classparser.LocalVariableTable;
 import de.inetsoftware.classparser.MethodInfo;
 import de.inetsoftware.jwebassembly.WasmException;
 
@@ -130,7 +131,7 @@ public class ModuleGenerator {
                 String impoarModule = (String)annotationValues.get( "module" );
                 String importName = (String)annotationValues.get( "name" );
                 writer.prepareImport( name, impoarModule, importName );
-                writeMethodSignature( method );
+                writeMethodSignature( method, null );
             } else {
                 writer.prepareFunction( name );
             }
@@ -162,7 +163,7 @@ public class ModuleGenerator {
                 byteCode = code.getByteCode();
                 writeCode( byteCode, method.getConstantPool() );
                 localVariables.calculate();
-                writeMethodSignature( method );
+                writeMethodSignature( method, code.getLocalVariableTable() );
 
                 for( WasmInstruction instruction : instructions ) {
                     instruction.writeTo( writer );
@@ -207,7 +208,7 @@ public class ModuleGenerator {
      * @throws WasmException
      *             if some Java code can't converted
      */
-    private void writeMethodSignature( MethodInfo method ) throws IOException, WasmException {
+    private void writeMethodSignature( MethodInfo method, LocalVariableTable variables ) throws IOException, WasmException {
         String signature = method.getDescription();
         String kind = "param";
         int paramCount = 0;
@@ -217,16 +218,29 @@ public class ModuleGenerator {
                 kind = "result";
                 continue;
             }
+            String name = null;
             if( kind == "param" ) {
+                if( variables != null ) {
+                    name = variables.getPosition( paramCount ).getName( method.getConstantPool() );
+                }
                 paramCount++;
             }
             type = ValueType.getValueType( signature, i );
             if( type != null ) {
-                writer.writeMethodParam( kind, type );
+                writer.writeMethodParam( kind, type, name );
             }
         }
         this.returnType = type;
-        writer.writeMethodParamFinish( localVariables.getLocalTypes( paramCount ) );
+        List<ValueType> localTypes = localVariables.getLocalTypes( paramCount );
+        for( int i = 0; i < localTypes.size(); i++ ) {
+            type = localTypes.get( i );
+            String name = null;
+            if( variables != null ) {
+                name = variables.getPosition( paramCount ).getName( method.getConstantPool() );
+            }
+            writer.writeMethodParam( "local", type, name );
+        }
+        writer.writeMethodParamFinish( );
     }
 
     /**

src/de/inetsoftware/jwebassembly/module/ModuleWriter.java

@@ -17,7 +17,6 @@ package de.inetsoftware.jwebassembly.module;
 
 import java.io.Closeable;
 import java.io.IOException;
-import java.util.List;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
@@ -90,22 +89,20 @@ public abstract class ModuleWriter implements Closeable {
      *            "param", "result" or "local"
      * @param valueType
      *            the data type of the parameter
+     * @param name
+     *            optional name of the parameter
      * @throws IOException
      *             if any I/O error occur
      */
-    protected abstract void writeMethodParam( String kind, ValueType valueType ) throws IOException;
+    protected abstract void writeMethodParam( String kind, ValueType valueType, @Nullable String name ) throws IOException;
 
     /**
      * Finish the function parameter.
      * 
-     * @param locals
-     *            a list with types of local variables
-     * 
-     * 
      * @throws IOException
      *             if any I/O error occur
      */
-    protected abstract void writeMethodParamFinish( List<ValueType> locals ) throws IOException;
+    protected abstract void writeMethodParamFinish() throws IOException;
 
     /**
      * Complete the method

src/de/inetsoftware/jwebassembly/text/TextModuleWriter.java

@@ -18,12 +18,12 @@ package de.inetsoftware.jwebassembly.text;
 import java.io.IOException;
 import java.util.HashMap;
 import java.util.HashSet;
-import java.util.List;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 
 import de.inetsoftware.classparser.ConstantRef;
+import de.inetsoftware.jwebassembly.JWebAssembly;
 import de.inetsoftware.jwebassembly.module.FunctionName;
 import de.inetsoftware.jwebassembly.module.ModuleWriter;
 import de.inetsoftware.jwebassembly.module.NumericOperator;
@@ -41,6 +41,8 @@ public class TextModuleWriter extends ModuleWriter {
 
     private Appendable      output;
 
+    private final boolean   debugNames;
+
     private StringBuilder   methodOutput = new StringBuilder();
 
     private int             inset;
@@ -61,6 +63,7 @@ public class TextModuleWriter extends ModuleWriter {
      */
     public TextModuleWriter( Appendable output, HashMap<String, String> properties ) throws IOException {
         this.output = output;
+        debugNames = Boolean.parseBoolean( properties.get( JWebAssembly.DEBUG_NAMES ) );
         output.append( "(module" );
         inset++;
     }
@@ -112,22 +115,22 @@ public class TextModuleWriter extends ModuleWriter {
      * {@inheritDoc}
      */
     @Override
-    protected void writeMethodParam( String kind, ValueType valueType ) throws IOException {
+    protected void writeMethodParam( String kind, ValueType valueType, @Nullable String name ) throws IOException {
-        methodOutput.append( " (" ).append( kind ).append( ' ' ).append( valueType.toString() ).append( ')' );
+        methodOutput.append( " (" ).append( kind );
+        if( debugNames && name != null ) {
+            methodOutput.append( " $" ).append( name );
+        }
+        methodOutput.append( ' ' ).append( valueType.toString() ).append( ')' );
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
-    protected void writeMethodParamFinish( List<ValueType> locals ) throws IOException {
+    protected void writeMethodParamFinish( ) throws IOException {
         if( isImport ) {
             isImport = false;
             output.append( "))" );
-        } else {
-            for( ValueType valueType : locals ) {
-                methodOutput.append( " (local " ).append( valueType.toString() ).append( ')' );
-            }
         }
     }