[Interpreter] Fixes a bug when popping context to correct level on break/continue.

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/scopes.h"
 #include "src/compiler.h"
 #include "src/interpreter/bytecode-register-allocator.h"
 #include "src/interpreter/control-flow-builders.h"
@@ skipping 344 matching lines @@
 
  private:
   TryFinallyBuilder* try_finally_builder_;
   DeferredCommands* commands_;
 };
 
 
 void BytecodeGenerator::ControlScope::PerformCommand(Command command,
                                                      Statement* statement) {
   ControlScope* current = this;
-  ContextScope* context = this->context();
+  ContextScope* context = generator()->execution_context();
   do {
-    if (current->Execute(command, statement)) { return; }
-    current = current->outer();
     if (current->context() != context) {
       // Pop context to the expected depth.
       // TODO(rmcilroy): Only emit a single context pop.

[rmcilroy, 2016/03/08 17:33:40]

nit - move TODO down below comment.

[mythria, 2016/03/09 10:24:45]

Done.

-      generator()->builder()->PopContext(current->context()->reg());
+      // pop contexts only for break and continue. For Return and throw it is

[rmcilroy, 2016/03/08 17:33:40]

nit /s/pop/Pop

[rmcilroy, 2016/03/08 17:33:40]

/s/Return/return

[mythria, 2016/03/09 10:24:44]

Done.

[mythria, 2016/03/09 10:24:45]

Done.

+      // not required to pop. Debuuger expects that the context is not popped on

[rmcilroy, 2016/03/08 17:33:40]

/s/debuuger/debugger

[mythria, 2016/03/09 10:24:45]

Done.

+      // return. So do not pop on return.
+      if (command == CMD_BREAK || command == CMD_CONTINUE) {
+        generator()->builder()->PopContext(current->context()->reg());
+      }
       context = current->context();
     }
+    if (current->Execute(command, statement)) {
+      return;
+    }
+    current = current->outer();
   } while (current != nullptr);
   UNREACHABLE();
 }
 
 
 class BytecodeGenerator::RegisterAllocationScope {
  public:
   explicit RegisterAllocationScope(BytecodeGenerator* generator)
       : generator_(generator),
         outer_(generator->register_allocator()),
@@ skipping 2757 matching lines @@
 }
 
 
 int BytecodeGenerator::feedback_index(FeedbackVectorSlot slot) const {
   return info()->feedback_vector()->GetIndex(slot);
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8