wasm gc: trying to fix virtual calls

core/src/main/java/org/teavm/backend/wasm/generate/gc/classes/WasmGCClassGenerator.java

@@ -100,7 +100,7 @@ public class WasmGCClassGenerator implements WasmGCClassInfoProvider, WasmGCInit
 
     private int classTagOffset;
     private int classFlagsOffset;
-    private int classNameOffset = -1;
+    private int classNameOffset;
     private int classParentOffset;
     private int classArrayOffset;
     private int classArrayItemOffset;
@@ -162,7 +162,10 @@ public class WasmGCClassGenerator implements WasmGCClassInfoProvider, WasmGCInit
             if (classInfo.virtualTableStructure != null && classInfo.getValueType() instanceof ValueType.Object
                     && classInfo.hasOwnVirtualTable) {
                 var className = ((ValueType.Object) classInfo.getValueType()).getClassName();
-                classInfo.virtualTableStructure.setSupertype(findVirtualTableSupertype(className));
+                var candidate = findVirtualTableSupertype(className);
+                if (candidate != null) {
+                    classInfo.virtualTableStructure.setSupertype(candidate);
+                }
             }
         }
     }
@@ -235,21 +238,29 @@ public class WasmGCClassGenerator implements WasmGCClassInfoProvider, WasmGCInit
                 var name = type instanceof ValueType.Object
                         ? ((ValueType.Object) type).getClassName()
                         : null;
+                var isInterface = false;
+                var classReader = name != null ? classSource.get(name) : null;
+                if (classReader != null && classReader.hasModifier(ElementModifier.INTERFACE)) {
+                    isInterface = true;
+                    classInfo.structure = standardClasses.objectClass().structure;
+                } else {
                     classInfo.structure = new WasmStructure(name != null ? names.forClass(name) : null);
+                    module.types.add(classInfo.structure);
+                }
                 if (name != null) {
-                    var classReader = classSource.get(name);
+                    if (!isInterface) {
-                    if (classReader == null || !classReader.hasModifier(ElementModifier.INTERFACE)) {
                         virtualTable = virtualTables.lookup(name);
                     }
-                    if (classReader != null && classReader.getParent() != null) {
+                    if (classReader != null && classReader.getParent() != null && !isInterface) {
                         classInfo.structure.setSupertype(getClassInfo(classReader.getParent()).structure);
                     }
                 } else {
                     classInfo.structure.setSupertype(standardClasses.objectClass().structure);
                 }
-                module.types.add(classInfo.structure);
+                if (!isInterface) {
                     fillFields(classInfo, type);
                     }
+            }
             var pointerName = names.forClassInstance(type);
             classInfo.hasOwnVirtualTable = virtualTable != null && virtualTable.hasValidEntries();
             var classStructure = classInfo.hasOwnVirtualTable
@@ -405,10 +416,7 @@ public class WasmGCClassGenerator implements WasmGCClassInfoProvider, WasmGCInit
                 var function = functionProvider.forInstanceMethod(entry.getImplementor());
                 if (!virtualTable.getClassName().equals(entry.getImplementor().getClassName())
                         || expectedFunctionType != function.getType()) {
-                    var functionType = typeMapper.getFunctionType(virtualTable.getClassName(), method, true);
+                    var wrapperFunction = new WasmFunction(expectedFunctionType);
-                    functionType.getSupertypes().add(expectedFunctionType);
-                    expectedFunctionType.setFinal(false);
-                    var wrapperFunction = new WasmFunction(functionType);
                     module.functions.add(wrapperFunction);
                     var call = new WasmCall(function);
                     var instanceParam = new WasmLocal(getClassInfo(virtualTable.getClassName()).getType());
@@ -451,7 +459,8 @@ public class WasmGCClassGenerator implements WasmGCClassInfoProvider, WasmGCInit
             if (methodDesc == null) {
                 structure.getFields().add(WasmType.Reference.FUNC.asStorage());
             } else {
-                var functionType = typeMapper.getFunctionType(virtualTable.getClassName(), methodDesc, false);
+                var originalVirtualTable = virtualTable.findMethodContainer(methodDesc);
+                var functionType = typeMapper.getFunctionType(originalVirtualTable.getClassName(), methodDesc, false);
                 structure.getFields().add(functionType.getReference().asStorage());
             }
         }
@@ -570,8 +579,9 @@ public class WasmGCClassGenerator implements WasmGCClassInfoProvider, WasmGCInit
             fields.add(supertypeGenerator.getFunctionType().getReference().asStorage());
             classNewArrayOffset = fields.size();
             fields.add(newArrayGenerator.getNewArrayFunctionType().getReference().asStorage());
+            classNameOffset = fields.size();
+            fields.add(standardClasses.stringClass().getType().asStorage());
             virtualTableFieldOffset = fields.size();
-            classNameOffset = fieldIndexes.getOrDefault(new FieldReference(className, "name"), -1);
         }
     }
 
@@ -654,14 +664,12 @@ public class WasmGCClassGenerator implements WasmGCClassInfoProvider, WasmGCInit
                 classFlagsOffset,
                 flagsExpr
         ));
-        if (classNameOffset >= 0) {
         function.getBody().add(new WasmStructSet(
                 standardClasses.classClass().getStructure(),
                 new WasmGetLocal(targetVar),
                 classNameOffset,
                 new WasmGetLocal(nameVar)
         ));
-        }
         function.getBody().add(new WasmStructSet(
                 standardClasses.classClass().getStructure(),
                 new WasmGetLocal(targetVar),

core/src/main/java/org/teavm/backend/wasm/generate/gc/methods/WasmGCGenerationVisitor.java

@@ -260,42 +260,41 @@ public class WasmGCGenerationVisitor extends BaseWasmGenerationVisitor {
             List<WasmExpression> arguments) {
         var vtable = context.virtualTables().lookup(method.getClassName());
         if (vtable != null) {
+            var cls = context.classes().get(method.getClassName());
+            assert cls != null : "Virtual table can't be generated for absent class";
+            if (cls.hasModifier(ElementModifier.INTERFACE)) {
+                vtable = pickVirtualTableForInterfaceCall(vtable, method.getDescriptor());
+            }
             vtable = vtable.findMethodContainer(method.getDescriptor());
         }
         if (vtable == null) {
             return new WasmUnreachable();
         }
-        var cls = context.classes().get(method.getClassName());
-        assert cls != null : "Virtual table can't be generated for absent class";
-
-        if (cls.hasModifier(ElementModifier.INTERFACE)) {
-            vtable = pickVirtualTableForInterfaceCall(vtable, method.getDescriptor());
-        }
 
         int vtableIndex = vtable.getMethods().indexOf(method.getDescriptor());
         if (vtable.getParent() != null) {
             vtableIndex += vtable.getParent().size();
         }
-        var instanceStruct = context.classInfoProvider().getClassInfo(vtable.getClassName()).getStructure();
 
-        var actualInstanceType = (WasmType.CompositeReference) instance.getType();
+        WasmExpression classRef = new WasmStructGet(context.standardClasses().objectClass().getStructure(),
-        var actualInstanceStruct = (WasmStructure) actualInstanceType.composite;
+                new WasmGetLocal(instance), WasmGCClassInfoProvider.CLASS_FIELD_OFFSET);
-        var actualVtableType = (WasmType.CompositeReference) actualInstanceStruct.getFields().get(0).asUnpackedType();
-        var actualVtableStruct = (WasmStructure) actualVtableType.composite;
-
-        WasmExpression classRef = new WasmStructGet(instanceStruct, new WasmGetLocal(instance),
-                WasmGCClassInfoProvider.CLASS_FIELD_OFFSET);
         var index = context.classInfoProvider().getVirtualMethodsOffset() + vtableIndex;
-        var vtableStruct = context.classInfoProvider().getClassInfo(vtable.getClassName())
+        var expectedInstanceClassInfo = context.classInfoProvider().getClassInfo(vtable.getClassName());
-                .getVirtualTableStructure();
+        var vtableStruct = expectedInstanceClassInfo.getVirtualTableStructure();
-        if (!vtableStruct.isSupertypeOf(actualVtableStruct)) {
         classRef = new WasmCast(classRef, vtableStruct.getReference());
-        }
 
         var functionRef = new WasmStructGet(vtableStruct, classRef, index);
         var functionTypeRef = (WasmType.CompositeReference) vtableStruct.getFields().get(index).asUnpackedType();
         var invoke = new WasmCallReference(functionRef, (WasmFunctionType) functionTypeRef.composite);
-        invoke.getArguments().addAll(arguments);
+        WasmExpression instanceRef = new WasmGetLocal(instance);
+        var instanceType = (WasmType.CompositeReference) instance.getType();
+        var instanceStruct = (WasmStructure) instanceType.composite;
+        if (!expectedInstanceClassInfo.getStructure().isSupertypeOf(instanceStruct)) {
+            instanceRef = new WasmCast(instanceRef, expectedInstanceClassInfo.getType());
+        }
+
+        invoke.getArguments().add(instanceRef);
+        invoke.getArguments().addAll(arguments.subList(1, arguments.size()));
         return invoke;
     }
 

core/src/main/java/org/teavm/backend/wasm/model/WasmCollection.java

@@ -43,6 +43,9 @@ public class WasmCollection<T extends WasmEntity> implements Iterable<T> {
     }
 
     public void add(T entity) {
+        if (entity.collection != null) {
+            throw new IllegalArgumentException("Entity already belongs some collection");
+        }
         if (!indexesInvalid) {
             entity.index = items.size();
         }

core/src/main/java/org/teavm/backend/wasm/model/WasmModule.java

@@ -98,7 +98,7 @@ public class WasmModule {
     }
 
     private void prepareTypes() {
-        var typeGraph = WasmTypeGraphBuilder.buildTypeGraph(types, types.size());
+        var typeGraph = WasmTypeGraphBuilder.buildTypeGraph(this, types, types.size());
         var sccs = GraphUtils.findStronglyConnectedComponents(typeGraph);
         var sccStartNode = new int[types.size()];
         for (var i = 0; i < sccStartNode.length; ++i) {

core/src/main/java/org/teavm/backend/wasm/model/WasmTypeGraphBuilder.java

@@ -22,21 +22,23 @@ final class WasmTypeGraphBuilder {
     private WasmTypeGraphBuilder() {
     }
 
-    static Graph buildTypeGraph(Iterable<WasmCompositeType> types, int size) {
+    static Graph buildTypeGraph(WasmModule module, Iterable<WasmCompositeType> types, int size) {
         var graphBuilder = new GraphBuilder(size);
-        var visitor = new GraphBuilderVisitor(graphBuilder);
+        var visitor = new GraphBuilderVisitor(module, graphBuilder);
         for (var type : types) {
-            visitor.currentIndex = type.index;
+            visitor.currentIndex = module.types.indexOf(type);
             type.acceptVisitor(visitor);
         }
         return graphBuilder.build();
     }
 
     private static class GraphBuilderVisitor implements WasmCompositeTypeVisitor {
+        final WasmModule module;
         final GraphBuilder graphBuilder;
         int currentIndex;
 
-        GraphBuilderVisitor(GraphBuilder graphBuilder) {
+        GraphBuilderVisitor(WasmModule module, GraphBuilder graphBuilder) {
+            this.module = module;
             this.graphBuilder = graphBuilder;
         }
 
@@ -71,7 +73,7 @@ final class WasmTypeGraphBuilder {
         private void addEdge(WasmType type) {
             if (type instanceof WasmType.CompositeReference) {
                 var composite = ((WasmType.CompositeReference) type).composite;
-                graphBuilder.addEdge(currentIndex, composite.index);
+                graphBuilder.addEdge(currentIndex, module.types.indexOf(composite));
             }
         }
     }

core/src/main/java/org/teavm/backend/wasm/model/expression/WasmStructGet.java

@@ -25,6 +25,7 @@ public class WasmStructGet extends WasmExpression {
     private WasmSignedType signedType;
 
     public WasmStructGet(WasmStructure type, WasmExpression instance, int fieldIndex) {
+        checkFieldIndex(fieldIndex);
         this.type = Objects.requireNonNull(type);
         this.instance = Objects.requireNonNull(instance);
         this.fieldIndex = fieldIndex;
@@ -51,6 +52,7 @@ public class WasmStructGet extends WasmExpression {
     }
 
     public void setFieldIndex(int fieldIndex) {
+        checkFieldIndex(fieldIndex);
         this.fieldIndex = fieldIndex;
     }
 
@@ -66,4 +68,10 @@ public class WasmStructGet extends WasmExpression {
     public void acceptVisitor(WasmExpressionVisitor visitor) {
         visitor.visit(this);
     }
+
+    private static void checkFieldIndex(int fieldIndex) {
+        if (fieldIndex < 0) {
+            throw new IllegalArgumentException("Field index must be >= 0");
+        }
+    }
 }

core/src/main/java/org/teavm/model/analysis/BaseTypeInference.java

@@ -316,12 +316,12 @@ public abstract class BaseTypeInference<T> {
 
         @Override
         public void visit(ClassConstantInstruction insn) {
-            type(insn.getReceiver(), ValueType.object("java/lang/Class"));
+            type(insn.getReceiver(), ValueType.object("java.lang.Class"));
         }
 
         @Override
         public void visit(StringConstantInstruction insn) {
-            type(insn.getReceiver(), ValueType.object("java/lang/String"));
+            type(insn.getReceiver(), ValueType.object("java.lang.String"));
         }
 
         @Override