JS: optimize case when JS method returns java.lang.Object and then treated as JS object

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

@@ -160,6 +160,10 @@ public abstract class BaseTypeInference<T> {
 
     protected abstract T elementType(T t);
 
+    protected T methodReturnType(MethodReference methodRef) {
+        return mapType(methodRef.getReturnType());
+    }
+
     private class InitialTypeVisitor extends AbstractInstructionVisitor {
         private GraphBuilder graphBuilder;
         private GraphBuilder arrayGraphBuilder;
@@ -280,7 +284,7 @@ public abstract class BaseTypeInference<T> {
 
         @Override
         public void visit(InvokeInstruction insn) {
-            type(insn.getReceiver(), insn.getMethod().getReturnType());
+            type(insn.getReceiver(), methodReturnType(insn.getMethod()));
         }
 
         @Override
@@ -338,5 +342,11 @@ public abstract class BaseTypeInference<T> {
                 }
             }
         }
+
+        void type(Variable target, T type) {
+            if (target != null && type != null) {
+                types[target.getIndex()] = type;
+            }
+        }
     }
 }

jso/impl/src/main/java/org/teavm/jso/impl/JSClassProcessor.java

@@ -224,7 +224,7 @@ class JSClassProcessor {
 
     void processProgram(MethodHolder methodToProcess) {
         setCurrentProgram(methodToProcess.getProgram());
-        types = new JSTypeInference(typeHelper, program, methodToProcess.getReference());
+        types = new JSTypeInference(typeHelper, classSource, program, methodToProcess.getReference());
         types.ensure();
         for (int i = 0; i < program.basicBlockCount(); ++i) {
             var block = program.basicBlockAt(i);
@@ -565,7 +565,8 @@ class JSClassProcessor {
         newInvoke.setArguments(newArgs.toArray(new Variable[0]));
         replacement.add(newInvoke);
         if (result != null) {
-            result = marshaller.unwrapReturnValue(callLocation, result, method.getResultType(), returnByRef);
+            result = marshaller.unwrapReturnValue(callLocation, result, method.getResultType(), returnByRef,
+                    canBeOnlyJava(invoke.getReceiver()));
             copyVar(result, invoke.getReceiver(), invoke.getLocation());
         }
 
@@ -585,7 +586,8 @@ class JSClassProcessor {
             Variable result = invoke.getReceiver() != null ? program.createVariable() : null;
             addPropertyGet(propertyName, invoke.getInstance(), result, invoke.getLocation(), pure);
             if (result != null) {
-                result = marshaller.unwrapReturnValue(callLocation, result, method.getResultType(), false);
+                result = marshaller.unwrapReturnValue(callLocation, result, method.getResultType(), false,
+                        canBeOnlyJava(invoke.getReceiver()));
                 copyVar(result, invoke.getReceiver(), invoke.getLocation());
             }
             return true;
@@ -617,7 +619,8 @@ class JSClassProcessor {
             addIndexerGet(invoke.getInstance(), marshaller.wrapArgument(callLocation, invoke.getArguments().get(0),
                     method.parameterType(0), false), result, invoke.getLocation());
             if (result != null) {
-                result = marshaller.unwrapReturnValue(callLocation, result, method.getResultType(), false);
+                result = marshaller.unwrapReturnValue(callLocation, result, method.getResultType(), false,
+                        canBeOnlyJava(invoke.getReceiver()));
                 copyVar(result, invoke.getReceiver(), invoke.getLocation());
             }
             return true;
@@ -665,6 +668,11 @@ class JSClassProcessor {
         return true;
     }
 
+    private boolean canBeOnlyJava(Variable variable) {
+        var type = types.typeOf(variable);
+        return type != JSType.JS && type != JSType.MIXED;
+    }
+
     private boolean processMethod(MethodReader method, CallLocation callLocation, InvokeInstruction invoke) {
         String name = method.getName();
 
@@ -699,7 +707,8 @@ class JSClassProcessor {
         newInvoke.setArguments(newArguments.toArray(new Variable[0]));
         replacement.add(newInvoke);
         if (result != null) {
-            result = marshaller.unwrapReturnValue(callLocation, result, method.getResultType(), false);
+            result = marshaller.unwrapReturnValue(callLocation, result, method.getResultType(), false,
+                    canBeOnlyJava(invoke.getReceiver()));
             copyVar(result, invoke.getReceiver(), invoke.getLocation());
         }
 
@@ -880,12 +889,12 @@ class JSClassProcessor {
         replacement.clear();
         if (!callee.hasModifier(ElementModifier.STATIC)) {
             insn.setInstance(marshaller.unwrapReturnValue(location, program.variableAt(paramIndex++),
-                    ValueType.object(calleeRef.getClassName()), false));
+                    ValueType.object(calleeRef.getClassName()), false, true));
         }
         Variable[] args = new Variable[callee.parameterCount()];
         for (int i = 0; i < callee.parameterCount(); ++i) {
             args[i] = marshaller.unwrapReturnValue(location, program.variableAt(paramIndex++),
-                    callee.parameterType(i), false);
+                    callee.parameterType(i), false, true);
         }
         insn.setArguments(args);
         if (callee.getResultType() != ValueType.VOID) {

jso/impl/src/main/java/org/teavm/jso/impl/JSObjectClassTransformer.java

@@ -130,7 +130,7 @@ class JSObjectClassTransformer implements ClassHolderTransformer {
 
             for (int i = 0; i < method.parameterCount(); ++i) {
                 variablesToPass[i] = marshaller.unwrapReturnValue(callLocation, variablesToPass[i],
-                        method.parameterType(i), false);
+                        method.parameterType(i), false, true);
             }
 
             basicBlock.addAll(marshallInstructions);

jso/impl/src/main/java/org/teavm/jso/impl/JSTypeInference.java

@@ -15,6 +15,8 @@
  */
 package org.teavm.jso.impl;
 
+import org.teavm.jso.JSBody;
+import org.teavm.model.ClassReaderSource;
 import org.teavm.model.MethodReference;
 import org.teavm.model.Program;
 import org.teavm.model.ValueType;
@@ -22,10 +24,12 @@ import org.teavm.model.analysis.BaseTypeInference;
 
 class JSTypeInference extends BaseTypeInference<JSType> {
     private JSTypeHelper typeHelper;
+    private ClassReaderSource classes;
 
-    JSTypeInference(JSTypeHelper typeHelper, Program program, MethodReference reference) {
+    JSTypeInference(JSTypeHelper typeHelper, ClassReaderSource classes, Program program, MethodReference reference) {
         super(program, reference);
         this.typeHelper = typeHelper;
+        this.classes = classes;
     }
 
     @Override
@@ -79,4 +83,20 @@ class JSTypeInference extends BaseTypeInference<JSType> {
     protected JSType elementType(JSType jsType) {
         return jsType instanceof JSType.ArrayType ? ((JSType.ArrayType) jsType).elementType : JSType.MIXED;
     }
+
+    @Override
+    protected JSType methodReturnType(MethodReference methodRef) {
+        if (!methodRef.getReturnType().isObject(Object.class)) {
+            return mapType(methodRef.getReturnType());
+        }
+        return isJsMethod(methodRef) ? JSType.MIXED : JSType.JAVA;
+    }
+
+    private boolean isJsMethod(MethodReference methodRef) {
+        if (typeHelper.isJavaScriptClass(methodRef.getClassName())) {
+            return true;
+        }
+        var method = classes.resolveImplementation(methodRef);
+        return method != null && method.getAnnotations().get(JSBody.class.getName()) != null;
+    }
 }

jso/impl/src/main/java/org/teavm/jso/impl/JSValueMarshaller.java

@@ -37,6 +37,10 @@ import org.teavm.model.instructions.InvokeInstruction;
 import org.teavm.model.instructions.StringConstantInstruction;
 
 class JSValueMarshaller {
+    private static final MethodReference JS_TO_JAVA = new MethodReference(JSWrapper.class, "jsToJava",
+            JSObject.class, Object.class);
+    private static final MethodReference LIGHTWEIGHT_JS_TO_JAVA = new MethodReference(JSWrapper.class,
+            "dependencyJsToJava", JSObject.class, Object.class);
     private static final ValueType stringType = ValueType.parse(String.class);
     private ReferenceCache referenceCache = new ReferenceCache();
     private Diagnostics diagnostics;
@@ -225,7 +229,8 @@ class JSValueMarshaller {
         return JSMethods.ARRAY_WRAPPER;
     }
 
-    Variable unwrapReturnValue(CallLocation location, Variable var, ValueType type, boolean byRef) {
+    Variable unwrapReturnValue(CallLocation location, Variable var, ValueType type, boolean byRef,
+            boolean strictJava) {
         if (byRef) {
             return unwrapByRef(location, var, type);
         }
@@ -237,7 +242,7 @@ class JSValueMarshaller {
                 return unwrapFunctor(location, var, cls);
             }
         }
-        return unwrap(location, var, type);
+        return unwrap(location, var, type, strictJava);
     }
 
     private Variable unwrapByRef(CallLocation location, Variable var, ValueType type) {
@@ -263,7 +268,7 @@ class JSValueMarshaller {
         return invokeMethod(location, JSMethods.DATA_TO_ARRAY, var);
     }
 
-    Variable unwrap(CallLocation location, Variable var, ValueType type) {
+    Variable unwrap(CallLocation location, Variable var, ValueType type, boolean strictJava) {
         if (type instanceof ValueType.Primitive) {
             switch (((ValueType.Primitive) type).getKind()) {
                 case BOOLEAN:
@@ -296,7 +301,7 @@ class JSValueMarshaller {
                 var wrapNative = new InvokeInstruction();
                 wrapNative.setLocation(location.getSourceLocation());
                 wrapNative.setType(InvocationType.SPECIAL);
-                wrapNative.setMethod(new MethodReference(JSWrapper.class, "jsToJava", JSObject.class, Object.class));
+                wrapNative.setMethod(strictJava ? JS_TO_JAVA : LIGHTWEIGHT_JS_TO_JAVA);
                 wrapNative.setArguments(var);
                 wrapNative.setReceiver(program.createVariable());
                 replacement.add(wrapNative);

jso/impl/src/main/java/org/teavm/jso/impl/JSWrapperGenerator.java

@@ -16,6 +16,7 @@
 package org.teavm.jso.impl;
 
 import java.io.IOException;
+import org.teavm.backend.javascript.rendering.Precedence;
 import org.teavm.backend.javascript.spi.Injector;
 import org.teavm.backend.javascript.spi.InjectorContext;
 import org.teavm.dependency.DependencyAgent;
@@ -36,11 +37,17 @@ public class JSWrapperGenerator implements Injector, DependencyPlugin {
             case "dependencyJsToJava":
             case "wrapperToJs":
             case "jsToWrapper":
-                context.writeExpr(context.getArgument(0));
+                context.writeExpr(context.getArgument(0), context.getPrecedence());
                 break;
             case "isJava":
+                if (context.getPrecedence().ordinal() >= Precedence.COMPARISON.ordinal()) {
+                    context.getWriter().append("(");
+                }
                 context.writeExpr(context.getArgument(0));
                 context.getWriter().append(" instanceof ").append("$rt_objcls").append("()");
+                if (context.getPrecedence().ordinal() >= Precedence.COMPARISON.ordinal()) {
+                    context.getWriter().append(")");
+                }
                 break;
         }
     }

tests/src/test/java/org/teavm/jso/test/JSWrapperTest.java

@@ -232,10 +232,12 @@ public class JSWrapperTest {
     @Test
     public void passJavaToJS() {
         var a = processObject(new A(23));
+        assertEquals("A(23)", a.toString());
         assertTrue(a instanceof A);
         assertEquals(23, ((A) a).getX());
 
         a = processObject(JSString.valueOf("qwe"));
+        assertEquals("qwe", a.toString());
         assertTrue(a instanceof JSString);
         assertEquals("qwe", ((JSString) a).stringValue());
 
@@ -263,5 +265,10 @@ public class JSWrapperTest {
         int getX() {
             return x;
         }
+
+        @Override
+        public String toString() {
+            return "A(" + x + ")";
+        }
     }
 }