[dart2js] new-rti: Implement basic is-test

Also add a few more type literal tests.

TBR=fishythefish@google.co,

Change-Id: Iab5ca4a5f8d224f67deaf1fe391e17ece46bde59
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/107600
Reviewed-by: Stephen Adams <sra@google.com>
Commit-Queue: Stephen Adams <sra@google.com>

pkg/compiler/lib/src/ssa/builder_kernel.dart

@@ -5302,6 +5302,13 @@ class KernelSsaGraphBuilder extends ir.Visitor {
       return;
     }
 
+    if (options.experimentNewRti) {
+      HInstruction rti =
+          _typeBuilder.analyzeTypeArgumentNewRti(typeValue, sourceElement);
+      push(HIsTest(typeValue, expression, rti, _abstractValueDomain.boolType));
+      return;
+    }
+
     if (typeValue is FunctionType) {
       HInstruction representation =
           _typeBuilder.analyzeTypeArgument(typeValue, sourceElement);

pkg/compiler/lib/src/ssa/codegen.dart

@@ -3340,6 +3340,8 @@ class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
 
   @override
   visitIsTest(HIsTest node) {
+    _registry.registerTypeUse(new TypeUse.isCheck(node.dartType));
+
     use(node.typeInput);
     js.Expression first = pop();
     use(node.checkedInput);

pkg/compiler/lib/src/ssa/nodes.dart

@@ -4348,7 +4348,10 @@ class HTypeInfoExpression extends HInstruction {
 /// lowered to other instructions, so this instruction remains for types that
 /// depend on type variables and complex types.
 class HIsTest extends HInstruction {
-  HIsTest(HInstruction checked, HInstruction rti, AbstractValue type)
+  final DartType dartType;
+
+  HIsTest(
+      this.dartType, HInstruction checked, HInstruction rti, AbstractValue type)
       : super([rti, checked], type) {
     setUseGvn();
   }

sdk/lib/_internal/js_runtime/lib/rti.dart

@@ -329,8 +329,8 @@ bool _generalIsTestImplementation(object) {
   // This static method is installed on an Rti object as a JavaScript instance
   // method. The Rti object is 'this'.
   Rti testRti = _castToRti(JS('', 'this'));
-  throw UnimplementedError(
-      '${Error.safeToString(object)} is ${_rtiToString(testRti, null)}');
+  Rti objectRti = instanceType(object);
+  return isSubtype(_theUniverse(), objectRti, testRti);
 }
 
 /// Called from generated code.

tests/compiler/dart2js_extra/rti/runtime_type_2_test.dart

@@ -14,9 +14,20 @@ Type grabList<T>() => grab<List<T>>();
 
 main() {
   Expect.equals('int', grab<int>().toString());
+
   Expect.identical(int, grab<int>());
+  Expect.identical(dynamic, grab<dynamic>());
+  Expect.identical(Object, grab<Object>());
+  Expect.identical(Null, grab<Null>());
 
   Expect.equals('List<int>', grabList<int>().toString());
+  Expect.equals('List<Null>', grabList<Null>().toString());
 
   Expect.equals('List<dynamic>', (List).toString());
+
+  Expect.equals('dynamic', (dynamic).toString());
+  Expect.equals('Object', (Object).toString());
+  Expect.equals('Null', (Null).toString());
+
+  Expect.equals(List, grabList<dynamic>());
 }

tests/compiler/dart2js_extra/rti/simple_is_test.dart

@@ -0,0 +1,40 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+//
+// dart2jsOptions=--experiment-new-rti --no-minify
+
+import 'dart:_rti' as rti;
+import "package:expect/expect.dart";
+
+class Thingy {}
+
+class Generic<AA> {
+  checkMethod(o) => o is AA;
+}
+
+@pragma('dart2js:noInline')
+void check<T>(o) {
+  Expect.isTrue(o is T);
+  Expect.isFalse(o is! T);
+}
+
+main() {
+  check<Thingy>(Thingy());
+
+  check<Generic<int>>(Generic<int>());
+
+  check<Generic<dynamic>>(Generic<dynamic>());
+  check<Generic<Object>>(Generic<Object>());
+  check<Generic<Object>>(Generic<dynamic>());
+  check<Generic<dynamic>>(Generic<Object>());
+
+  Expect.isTrue(Generic<Thingy>().checkMethod(Thingy()));
+  Expect.isTrue(Generic<Object>().checkMethod(Object()));
+  Expect.isTrue(Generic<Object>().checkMethod(Thingy()));
+  Expect.isFalse(Generic<Thingy>().checkMethod(Object()));
+  Expect.isTrue(Generic<dynamic>().checkMethod(Object()));
+
+  Expect.isFalse(Generic<Thingy>().checkMethod(123));
+  Expect.isFalse(Generic<Thingy>().checkMethod(Object()));
+}