[generators] Always call function with closure context when resuming.

src/interpreter/bytecode-generator.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/interpreter/bytecode-generator.h"
 
 #include "src/ast/compile-time-value.h"
 #include "src/ast/scopes.h"
 #include "src/builtins/builtins-constructor.h"
 #include "src/code-stubs.h"
@@ skipping 781 matching lines @@
   // The generator resume trampoline abuses the new.target register both to
   // indicate that this is a resume call and to pass in the generator object.
   // In ordinary calls, new.target is always undefined because generator
   // functions are non-constructable.
   Register generator_object = Register::new_target();
   BytecodeLabel regular_call;
   builder()
       ->LoadAccumulatorWithRegister(generator_object)
       .JumpIfUndefined(&regular_call);
 
-  // This is a resume call. Restore registers and perform state dispatch.
-  // (The current context has already been restored by the trampoline.)
+  // This is a resume call. Restore the current context and the registers, then
+  // perform state dispatch.
+  Register dummy = register_allocator()->NewRegister();
   builder()
-      ->ResumeGenerator(generator_object)
+      ->CallRuntime(Runtime::kInlineGeneratorGetContext, generator_object)
+      .PushContext(dummy)
+      .ResumeGenerator(generator_object)
       .StoreAccumulatorInRegister(generator_state_);
   BuildIndexedJump(generator_state_, 0, generator_resume_points_.size(),
                    generator_resume_points_);
 
   builder()
       ->Bind(&regular_call)
       .LoadLiteral(Smi::FromInt(JSGeneratorObject::kGeneratorExecuting))
       .StoreAccumulatorInRegister(generator_state_);
   // This is a regular call. Fall through to the ordinary function prologue,
   // after which we will run into the generator object creation and other extra
@@ skipping 2543 matching lines @@
 }
 
 Runtime::FunctionId BytecodeGenerator::StoreKeyedToSuperRuntimeId() {
   return is_strict(language_mode()) ? Runtime::kStoreKeyedToSuper_Strict
                                     : Runtime::kStoreKeyedToSuper_Sloppy;
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8