Kernel/VM: Set the instantiator type arguments on closures

runtime/vm/kernel_to_il.cc

 // Copyright (c) 2016, 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.
 
 #include <set>
 
 #include "vm/kernel_to_il.h"
 
 #include "vm/compiler.h"
 #include "vm/intermediate_language.h"
@@ skipping 3780 matching lines @@
 
 
 Fragment FlowGraphBuilder::BuildImplicitClosureCreation(
     const Function& target) {
   Fragment fragment;
   const dart::Class& closure_class =
       dart::Class::ZoneHandle(Z, I->object_store()->closure_class());
   fragment += AllocateObject(closure_class, target);
   LocalVariable* closure = MakeTemporary();
 
+  // The function signature can have uninstantiated class type parameters.
+  //
+  // TODO(regis): Also handle the case of a function signature that has
+  // uninstantiated function type parameters.
+  if (!target.HasInstantiatedSignature(kCurrentClass)) {
+    fragment += LoadLocal(closure);
+    fragment += LoadInstantiatorTypeArguments();
+    fragment +=
+        StoreInstanceField(TokenPosition::kNoSource,
+                           Closure::instantiator_type_arguments_offset());
+  }
+
   // Allocate a context that closes over `this`.
   fragment += AllocateContext(1);
   LocalVariable* context = MakeTemporary();
 
   // Store the function and the context in the closure.
   fragment += LoadLocal(closure);
   fragment += Constant(target);
   fragment +=
       StoreInstanceField(TokenPosition::kNoSource, Closure::function_offset());
 
@@ skipping 2879 matching lines @@
     }
     break;
   }
 
   const dart::Class& closure_class =
       dart::Class::ZoneHandle(Z, I->object_store()->closure_class());
   ASSERT(!closure_class.IsNull());
   Fragment instructions = AllocateObject(closure_class, function);
   LocalVariable* closure = MakeTemporary();
 
-  // TODO(27590): Generic closures need type arguments.
+  // The function signature can have uninstantiated class type parameters.
+  //
+  // TODO(regis): Also handle the case of a function signature that has
+  // uninstantiated function type parameters.
+  if (!function.HasInstantiatedSignature(kCurrentClass)) {
+    instructions += LoadLocal(closure);
+    instructions += LoadInstantiatorTypeArguments();
+    instructions +=
+        StoreInstanceField(TokenPosition::kNoSource,
+                           Closure::instantiator_type_arguments_offset());
+  }
 
   // Store the function and the context in the closure.
   instructions += LoadLocal(closure);
   instructions += Constant(function);
   instructions +=
       StoreInstanceField(TokenPosition::kNoSource, Closure::function_offset());
 
   instructions += LoadLocal(closure);
   instructions += LoadLocal(parsed_function_->current_context_var());
   instructions +=
@@ skipping 128 matching lines @@
     thread->clear_sticky_error();
     return error.raw();
   }
 }
 
 
 }  // namespace kernel
 }  // namespace dart
 
 #endif  // !defined(DART_PRECOMPILED_RUNTIME)