From d81da1f342af79792a9603516dc5cabdc4f3f4ec Mon Sep 17 00:00:00 2001
From: Volker <Volker@Volker.fritz.box>
Date: Fri, 27 Jul 2018 18:30:04 +0200
Subject: [PATCH] Use byte values for ValeTypes instead of Varint values.
 Prepare for ref values.

---
 .../jwebassembly/binary/BinaryModuleWriter.java | 14 +++++++-------
 .../jwebassembly/binary/InstructionOpcodes.java |  6 ++++++
 .../jwebassembly/module/ValueType.java          | 17 ++++++++++-------
 3 files changed, 23 insertions(+), 14 deletions(-)

diff --git a/src/de/inetsoftware/jwebassembly/binary/BinaryModuleWriter.java b/src/de/inetsoftware/jwebassembly/binary/BinaryModuleWriter.java
index 4a1e5eb..b3a3326 100644
--- a/src/de/inetsoftware/jwebassembly/binary/BinaryModuleWriter.java
+++ b/src/de/inetsoftware/jwebassembly/binary/BinaryModuleWriter.java
@@ -105,16 +105,16 @@ public class BinaryModuleWriter extends ModuleWriter implements InstructionOpcod
             WasmOutputStream stream = new WasmOutputStream();
             stream.writeVaruint32( count );
             for( FunctionType type : functionTypes ) {
-                stream.writeVarint( ValueType.func.getCode() );
+                stream.write( ValueType.func.getCode() );
                 stream.writeVaruint32( type.params.size() );
                 for( ValueType valueType : type.params ) {
-                    stream.writeVarint( valueType.getCode() );
+                    stream.write( valueType.getCode() );
                 }
                 if( type.result == null ) {
                     stream.writeVaruint32( 0 );
                 } else {
                     stream.writeVaruint32( 1 );
-                    stream.writeVarint( type.result.getCode() );
+                    stream.write( type.result.getCode() );
                 }
             }
             wasm.writeSection( SectionType.Type, stream, null );
@@ -295,7 +295,7 @@ public class BinaryModuleWriter extends ModuleWriter implements InstructionOpcod
         localsStream.writeVaruint32( locals.size() );
         for( ValueType valueType : locals ) {
             localsStream.writeVaruint32( 1 ); // TODO optimize, write the count of same types.
-            localsStream.writeVarint( valueType.getCode() );
+            localsStream.write( valueType.getCode() );
         }
         functionsStream.writeVaruint32( localsStream.size() + codeStream.size() + 1 );
         localsStream.writeTo( functionsStream );
@@ -692,7 +692,7 @@ public class BinaryModuleWriter extends ModuleWriter implements InstructionOpcod
                 break;
             case IF:
                 codeStream.write( IF );
-                codeStream.write( 0x40 ); // void; the return type of the block. currently we does not use it
+                codeStream.write( ValueType.empty.getCode() ); // void; the return type of the block. currently we does not use it
                 break;
             case ELSE:
                 codeStream.write( ELSE );
@@ -705,7 +705,7 @@ public class BinaryModuleWriter extends ModuleWriter implements InstructionOpcod
                 break;
             case BLOCK:
                 codeStream.write( BLOCK );
-                codeStream.write( 0x40 ); // void; the return type of the block. currently we does not use it
+                codeStream.write( ValueType.empty.getCode() ); // void; the return type of the block. currently we does not use it
                 break;
             case BR:
                 codeStream.write( BR );
@@ -725,7 +725,7 @@ public class BinaryModuleWriter extends ModuleWriter implements InstructionOpcod
                 break;
             case LOOP:
                 codeStream.write( LOOP );
-                codeStream.write( 0x40 ); // void; the return type of the loop. currently we does not use it
+                codeStream.write( ValueType.empty.getCode() ); // void; the return type of the loop. currently we does not use it
                 break;
             case UNREACHABLE:
                 codeStream.write( UNREACHABLE );
diff --git a/src/de/inetsoftware/jwebassembly/binary/InstructionOpcodes.java b/src/de/inetsoftware/jwebassembly/binary/InstructionOpcodes.java
index a97d0d7..8a42021 100644
--- a/src/de/inetsoftware/jwebassembly/binary/InstructionOpcodes.java
+++ b/src/de/inetsoftware/jwebassembly/binary/InstructionOpcodes.java
@@ -334,4 +334,10 @@ interface InstructionOpcodes {
     static final int F64_CONVERT_U_I64      = 0xBA;
 
     static final int F64_PROMOTE_F32        = 0xBB;
+
+    // === numerical operations ======
+
+    static final int REF_NULL               = 0xD0;
+
+    static final int REF_ISNULL             = 0xD1;
 }
diff --git a/src/de/inetsoftware/jwebassembly/module/ValueType.java b/src/de/inetsoftware/jwebassembly/module/ValueType.java
index 2058c18..0f390d5 100644
--- a/src/de/inetsoftware/jwebassembly/module/ValueType.java
+++ b/src/de/inetsoftware/jwebassembly/module/ValueType.java
@@ -19,14 +19,17 @@ package de.inetsoftware.jwebassembly.module;
  * @author Volker Berlin
  */
 public enum ValueType {
-    i32(-1),
-    i64(-2),
-    f32(-3),
-    f64(-4),
-    func(-0x20);
-    // void(-0x40);
+    i32(0x7f),
+    i64(0x7e),
+    f32(0x7d),
+    f64(0x7c),
+    anyfunc(0x70),
+    anyref(0x6f),
+    func(0x60),
+    empty(0x40), // empty block_type
+    ;
 
-    private int code;
+    private final int code;
 
     /**
      * Create instance of the enum