implements INSTANCEOF operation

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

@@ -52,6 +52,11 @@ public class TypeManager {
     /** name of virtual function table, start with a point for an invalid Java identifier  */
     static final String             VTABLE = ".vtable";
 
+    /**
+     * The reserved position on start of the vtable:
+     * <li>offset of interface call table (itable)
+     * <li>offset of instanceof list
+     */
     private static final int        VTABLE_FIRST_FUNCTION_INDEX = 2;
 
     private Map<String, StructType> structTypes = new LinkedHashMap<>();
@@ -132,13 +137,13 @@ public class TypeManager {
     }
 
     /**
-     * Get the FunctionName for a virtual call and mark it as used. The function has 2 parameters (THIS,
+     * Create the FunctionName for a virtual call and mark it as used. The function has 2 parameters (THIS,
      * virtualfunctionIndex) and returns the index of the function.
      * 
      * @return the name
      */
     @Nonnull
-    WatCodeSyntheticFunctionName getCallVirtualGC() {
+    WatCodeSyntheticFunctionName createCallVirtualGC() {
         return new WatCodeSyntheticFunctionName( //
                         "callVirtual", "local.get 0 " // THIS
                                         + "struct.get java/lang/Object .vtable " // vtable is on index 0
@@ -149,6 +154,49 @@ public class TypeManager {
                         , valueOf( "java/lang/Object" ), ValueType.i32, null, ValueType.i32 ); //
     }
 
+    /**
+     * Create the FunctionName for the INSTANCEOF operation and mark it as used. The function has 2 parameters (THIS,
+     * classIndex) and returns true if there is a match.
+     * 
+     * @return the name
+     */
+    WatCodeSyntheticFunctionName createInstanceOf() {
+        return new WatCodeSyntheticFunctionName( //
+                        "instanceof", "local.get 0 " // THIS
+                                        + "struct.get java/lang/Object .vtable " // vtable is on index 0
+                                        + "local.tee 2 " // save the vtable location
+                                        + "i32.load offset=4 align=4 " // get offset of instanceof inside vtable (int position 1, byte position 4)
+                                        + "local.get 2 " // get the vtable location
+                                        + "i32.add " //
+                                        + "local.tee 2 " // save the instanceof location
+                                        + "i32.load offset=0 align=4 " // count of instanceof entries
+                                        + "i32.const 4 " //
+                                        + "i32.mul " //
+                                        + "local.get 2 " // get the instanceof location
+                                        + "i32.add " //
+                                        + "local.set 3 " // save end position
+                                        + "loop" //
+                                        + "  local.get 2 " // get the instanceof location pointer
+                                        + "  local.get 3 " // get the end location
+                                        + "  i32.eq" //
+                                        + "  if" // current offset == end offset
+                                        + "    i32.const 0" // not found
+                                        + "    return" //
+                                        + "  end" //
+                                        + "  local.get 2" // get the instanceof location pointer
+                                        + "  i32.const 4" //
+                                        + "  i32.add" // increment offset
+                                        + "  local.tee 2" // save the instanceof location pointer
+                                        + "  i32.load offset=0 align=4" //
+                                        + "  local.get 1" // the class index that we search
+                                        + "  i32.ne" //
+                                        + "  br_if 0 " //
+                                        + "end " //
+                                        + "i32.const 1 " // class/interface found
+                                        + "return " //
+                        , valueOf( "java/lang/Object" ), ValueType.i32, null, ValueType.i32 ); //
+    }
+
     /**
      * A reference to a type.
      * 
@@ -259,9 +307,9 @@ public class TypeManager {
                 }
             }
 
-            // add all interfaces to the instanceof
+            // add all interfaces to the instanceof set
             for(ConstantClass interClass : classFile.getInterfaces() ) {
-                StructType type = types.structTypes.get( className );
+                StructType type = types.structTypes.get( interClass.getName() );
                 if( type != null ) {
                     instanceOFs.add( type );
                 }

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

@@ -52,11 +52,6 @@ import de.inetsoftware.jwebassembly.wasm.WasmBlockOperator;
  */
 public abstract class WasmCodeBuilder {
 
-    /**
-     * declare for frequently use of virtual call with non GC mode.
-     */
-    static final SyntheticFunctionName GET_I32 = new JavaScriptSyntheticFunctionName( "NonGC", "get_i32", () -> "(a,i) => a[i]", ValueType.anyref, ValueType.i32, null, ValueType.i32 );
-
     private final LocaleVariableManager localVariables = new LocaleVariableManager();
 
     private final List<WasmInstruction> instructions   = new ArrayList<>();
@@ -497,11 +492,7 @@ public abstract class WasmCodeBuilder {
         }
         indirectCall.setVariableIndexOfThis( varIndex );
         instructions.add( indirectCall );
-        if( !options.useGC() ) {
+        options.registerGet_i32(); // for later access of the vtable
-            // for later access of the vtable
-            functions.markAsNeeded( GET_I32 );
-            functions.markAsImport( GET_I32, GET_I32.getAnnotation() );
-        }
     }
 
     /**
@@ -643,6 +634,12 @@ public abstract class WasmCodeBuilder {
      *            the line number in the Java source code
      */
     protected void addStructInstruction( StructOperator op, @Nonnull String typeName, @Nullable NamedStorageType fieldName, int javaCodePos, int lineNumber ) {
+        if( op == StructOperator.INSTANCEOF ) {
+            instructions.add( new WasmConstInstruction( types.valueOf( typeName ).getClassIndex(), javaCodePos, lineNumber ) );
+            FunctionName name = options.getInstanceOf();
+            instructions.add( new WasmCallInstruction( name, javaCodePos, lineNumber, types, false ) );
+            return;
+        }
         WasmStructInstruction structInst = new WasmStructInstruction( op, typeName, fieldName, javaCodePos, lineNumber, types );
         instructions.add( structInst );
         if( !options.useGC() ) {

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

@@ -20,11 +20,13 @@ import java.util.HashMap;
 import javax.annotation.Nonnull;
 
 import de.inetsoftware.jwebassembly.JWebAssembly;
+import de.inetsoftware.jwebassembly.javascript.JavaScriptSyntheticFunctionName;
 import de.inetsoftware.jwebassembly.module.CodeOptimizer;
 import de.inetsoftware.jwebassembly.module.FunctionManager;
 import de.inetsoftware.jwebassembly.module.FunctionName;
 import de.inetsoftware.jwebassembly.module.StringManager;
 import de.inetsoftware.jwebassembly.module.TypeManager;
+import de.inetsoftware.jwebassembly.wasm.ValueType;
 
 /**
  * The option/properties for the behavior of the compiler.
@@ -55,9 +57,12 @@ public class WasmOptions {
      */
     public FunctionName ref_eq;
 
+    private FunctionName get_i32;
 
     private FunctionName callVirtual;
 
+    private FunctionName instanceOf;
+
     /**
      * Create a new instance of options
      * 
@@ -112,6 +117,21 @@ public class WasmOptions {
         return sourceMapBase;
     }
 
+    /**
+     * Register FunctionName "NonGC.get_i32" for frequently access to vtable with non GC mode.
+     */
+    void registerGet_i32() {
+        if( useGC ) {
+            return;
+        }
+        if( get_i32 == null ) {
+            SyntheticFunctionName name;
+            get_i32 = name = new JavaScriptSyntheticFunctionName( "NonGC", "get_i32", () -> "(a,i) => a[i]", ValueType.anyref, ValueType.i32, null, ValueType.i32 );
+            functions.markAsNeeded( name );
+            functions.markAsImport( name, name.getAnnotation() );
+        }
+    }
+
     /**
      * Get the FunctionName for a virtual call and mark it as used. The function has 2 parameters (THIS,
      * virtualfunctionIndex) and returns the index of the function.
@@ -122,8 +142,26 @@ public class WasmOptions {
     FunctionName getCallVirtual() {
         FunctionName name = callVirtual;
         if( name == null ) {
-            callVirtual = name = types.getCallVirtualGC();
+            callVirtual = name = types.createCallVirtualGC();
             functions.markAsNeeded( name );
+            registerGet_i32();
+        }
+        return name;
+    }
+
+    /**
+     * Get the FunctionName for an INSTANCEOF check and mark it as used. The function has 2 parameters (THIS,
+     * classIndex) and returns true or false.
+     * 
+     * @return the name
+     */
+    @Nonnull
+    FunctionName getInstanceOf() {
+        FunctionName name = instanceOf;
+        if( name == null ) {
+            instanceOf = name = types.createInstanceOf();
+            functions.markAsNeeded( name );
+            registerGet_i32();
         }
         return name;
     }

test/de/inetsoftware/jwebassembly/runtime/RuntimeErrors.java

@@ -126,19 +126,6 @@ public class RuntimeErrors {
         }
     }
 
-    @Test
-    public void instanceofCall() throws IOException {
-        compileErrorTest( "Unknown operator: INSTANCEOF", InstanceofMethod.class );
-    }
-
-    static class InstanceofMethod {
-        @Export
-        static boolean runnable() {
-            Object obj = new Object();
-            return obj instanceof Integer;
-        }
-    }
-
     @Test
     public void checkcast() throws IOException {
         compileErrorTest( "Unknown operator: CAST", CheckcastMethod.class );

test/de/inetsoftware/jwebassembly/runtime/StructsNonGC.java

@@ -17,6 +17,8 @@ package de.inetsoftware.jwebassembly.runtime;
 
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.LinkedList;
+import java.util.List;
 
 import org.junit.ClassRule;
 import org.junit.runners.Parameterized.Parameters;
@@ -50,6 +52,9 @@ public class StructsNonGC extends AbstractBaseTest {
             addParam( list, script, "useGlobalObject" );
             addParam( list, script, "multipleAssign" );
             addParam( list, script, "getDefaultValue" );
+            addParam( list, script, "instanceof1" );
+            addParam( list, script, "instanceof2" );
+            addParam( list, script, "instanceof3" );
         }
         rule.setTestParameters( list );
         return list;
@@ -143,6 +148,24 @@ public class StructsNonGC extends AbstractBaseTest {
             Abc2 val = new Abc2();
             return val.getDefault();
         }
+
+        @Export
+        static boolean instanceof1() {
+            Object obj = new Object();
+            return obj instanceof Integer;
+        }
+
+        @Export
+        static boolean instanceof2() {
+            Object obj = new Object();
+            return obj instanceof Object;
+        }
+
+        @Export
+        static boolean instanceof3() {
+            Object obj = new LinkedList();
+            return obj instanceof List;
+        }
     }
 
     interface TestDefault {