From 97b7b9dafd3c9ab25c66c4d77e1a1cb41bfc5796 Mon Sep 17 00:00:00 2001
From: Volker Berlin <volker.berlin@googlemail.com>
Date: Tue, 26 Mar 2019 18:21:20 +0100
Subject: [PATCH] passing code position for a source map. #6

---
 .../jwebassembly/binary/BinaryModuleWriter.java    |  8 ++++++++
 .../inetsoftware/jwebassembly/binary/Function.java | 14 +++++++++++++-
 .../jwebassembly/module/ModuleGenerator.java       |  7 +++++++
 .../jwebassembly/module/ModuleWriter.java          |  8 ++++++++
 .../jwebassembly/text/TextModuleWriter.java        |  8 ++++++++
 5 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/src/de/inetsoftware/jwebassembly/binary/BinaryModuleWriter.java b/src/de/inetsoftware/jwebassembly/binary/BinaryModuleWriter.java
index ab8f1042..94b19498 100644
--- a/src/de/inetsoftware/jwebassembly/binary/BinaryModuleWriter.java
+++ b/src/de/inetsoftware/jwebassembly/binary/BinaryModuleWriter.java
@@ -394,6 +394,14 @@ protected void writeMethodParamFinish() throws IOException {
         function.typeId = typeId;
     }
 
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected void markCodePosition( int javaCodePosition ) {
+        function.markCodePosition( codeStream.size(), javaCodePosition );
+    }
+
     /**
      * {@inheritDoc}
      */
diff --git a/src/de/inetsoftware/jwebassembly/binary/Function.java b/src/de/inetsoftware/jwebassembly/binary/Function.java
index 0caa30b4..3078699e 100644
--- a/src/de/inetsoftware/jwebassembly/binary/Function.java
+++ b/src/de/inetsoftware/jwebassembly/binary/Function.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 - 2018 Volker Berlin (i-net software)
+ * Copyright 2017 - 2019 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.
@@ -40,4 +40,16 @@ class Function extends SectionEntry {
     void writeSectionEntry( WasmOutputStream stream ) throws IOException {
         stream.writeVaruint32( this.typeId );
     }
+
+    /**
+     * Add code position marker for a source map.
+     * 
+     * @param streamPosition
+     *            the position in the function stream
+     * @param javaCodePosition
+     *            the position in the Java Source file
+     */
+    void markCodePosition( int streamPosition, int javaCodePosition ) {
+        // TODO Auto-generated method stub
+    }
 }
diff --git a/src/de/inetsoftware/jwebassembly/module/ModuleGenerator.java b/src/de/inetsoftware/jwebassembly/module/ModuleGenerator.java
index 25b381bf..ba544ee9 100644
--- a/src/de/inetsoftware/jwebassembly/module/ModuleGenerator.java
+++ b/src/de/inetsoftware/jwebassembly/module/ModuleGenerator.java
@@ -369,6 +369,8 @@ private void writeMethodImpl( FunctionName name, boolean isStatic, LocalVariable
 
         List<WasmInstruction> instructions = codeBuilder.getInstructions();
         optimizer.optimze( instructions );
+
+        int lastCodePosition = -1;
         for( WasmInstruction instruction : instructions ) {
             switch( instruction.getType() ) {
                 case Block:
@@ -388,6 +390,11 @@ private void writeMethodImpl( FunctionName name, boolean isStatic, LocalVariable
                     break;
                 default:
             }
+            int codePosition = instruction.getCodePosition();
+            if( codePosition >= 0 && codePosition != lastCodePosition ) {
+                writer.markCodePosition( codePosition );
+                lastCodePosition = codePosition;
+            }
             instruction.writeTo( writer );
         }
         writer.writeMethodFinish();
diff --git a/src/de/inetsoftware/jwebassembly/module/ModuleWriter.java b/src/de/inetsoftware/jwebassembly/module/ModuleWriter.java
index c3e05fea..c229f42e 100644
--- a/src/de/inetsoftware/jwebassembly/module/ModuleWriter.java
+++ b/src/de/inetsoftware/jwebassembly/module/ModuleWriter.java
@@ -126,6 +126,14 @@ public void prepareFinish() {
      */
     protected abstract void writeMethodParamFinish() throws IOException;
 
+    /**
+     * Mark the current output position with Java code position for crating of a source map.
+     * 
+     * @param javaCodePosition
+     *            the position in the Java code
+     */
+    protected abstract void markCodePosition( int javaCodePosition );
+
     /**
      * Complete the method
      * 
diff --git a/src/de/inetsoftware/jwebassembly/text/TextModuleWriter.java b/src/de/inetsoftware/jwebassembly/text/TextModuleWriter.java
index 125f6e54..456e8ff5 100644
--- a/src/de/inetsoftware/jwebassembly/text/TextModuleWriter.java
+++ b/src/de/inetsoftware/jwebassembly/text/TextModuleWriter.java
@@ -198,6 +198,14 @@ protected void writeMethodParamFinish( ) throws IOException {
         }
     }
 
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected void markCodePosition( int javaCodePosition ) {
+        // nothing
+    }
+
     /**
      * {@inheritDoc}
      */