From 33feee3b030c24f85a7f5a5c8475ef4f7aa1780b Mon Sep 17 00:00:00 2001
From: Alexander Markov <alexmarkov@google.com>
Date: Wed, 13 Jun 2018 22:28:04 +0000
Subject: [PATCH] [vm/kernel/bytecode] Fix arguments passing in native factory
 constructors
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VM requires to pass null type arguments to factory constructors of
non-generic classes. This includes native implementation of native
factory constructors.

Bytecode generation for bodies of native factory constructors is fixed
to push this extra argument for NativeCall.

Change-Id: I741a783c6964da88ecd0bfd1d2ec4aa3b1868708
Reviewed-on: https://dart-review.googlesource.com/60200
Reviewed-by: Zach Anderson <zra@google.com>
Reviewed-by: Régis Crelier <regis@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
---
 pkg/vm/lib/bytecode/gen_bytecode.dart           |  5 +++++
 .../testcases/bytecode/instance_creation.dart   |  6 ++++++
 .../bytecode/instance_creation.dart.expect      | 17 +++++++++++++++++
 3 files changed, 28 insertions(+)

diff --git a/pkg/vm/lib/bytecode/gen_bytecode.dart b/pkg/vm/lib/bytecode/gen_bytecode.dart
index 797bc67c615..4e218c891b1 100644
--- a/pkg/vm/lib/bytecode/gen_bytecode.dart
+++ b/pkg/vm/lib/bytecode/gen_bytecode.dart
@@ -152,6 +152,11 @@ class BytecodeGenerator extends RecursiveVisitor<Null> {
 
     if (locals.hasTypeArgsVar) {
       asm.emitPush(locals.typeArgsVarIndexInFrame);
+    } else if (enclosingMember is Procedure &&
+        (enclosingMember as Procedure).isFactory) {
+      // Null type arguments are passed to factory constructors even if class
+      // is not generic. TODO(alexmarkov): Clean this up.
+      _genPushNull();
     }
     if (locals.hasReceiver) {
       asm.emitPush(locals.getVarIndexInFrame(locals.receiverVar));
diff --git a/pkg/vm/testcases/bytecode/instance_creation.dart b/pkg/vm/testcases/bytecode/instance_creation.dart
index 5821f59a9d8..85ea5d71f54 100644
--- a/pkg/vm/testcases/bytecode/instance_creation.dart
+++ b/pkg/vm/testcases/bytecode/instance_creation.dart
@@ -2,6 +2,8 @@
 // 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.
 
+// ignore_for_file: native_function_body_in_non_sdk_code
+
 class Base<T1, T2> {
   T1 t1;
   T2 t2;
@@ -67,6 +69,10 @@ void foo5() {
   new I.test_factory2(param: 42);
 }
 
+class J {
+  factory J() native "agent_J";
+}
+
 main() {
   foo1();
   foo2();
diff --git a/pkg/vm/testcases/bytecode/instance_creation.dart.expect b/pkg/vm/testcases/bytecode/instance_creation.dart.expect
index 32c2c325ec3..be92aa5b66e 100644
--- a/pkg/vm/testcases/bytecode/instance_creation.dart.expect
+++ b/pkg/vm/testcases/bytecode/instance_creation.dart.expect
@@ -1,6 +1,7 @@
 library #lib;
 import self as self;
 import "dart:core" as core;
+import "dart:_internal" as _in;
 
 class Base<T1 extends core::Object = dynamic, T2 extends core::Object = dynamic> extends core::Object {
   generic-covariant-impl field self::Base::T1 t1 = null;
@@ -385,6 +386,22 @@ ConstantPool {
 ]  static factory test_factory2({dynamic param = null}) → self::I
     return new self::I::•(param);
 }
+class J extends core::Object {
+[@vm.bytecode=
+Bytecode {
+  Entry                0
+  CheckStack
+  PushConstant         CP#0
+  NativeCall           CP#1
+  ReturnTOS
+}
+ConstantPool {
+  [0] = Null
+  [1] = NativeEntry agent_J
+}
+]  @_in::ExternalName::•("agent_J")
+  external static factory •() → self::J;
+}
 [@vm.bytecode=
 Bytecode {
   Entry                1