Use a different map to distinguish eval contexts

src/factory.h

 // Copyright 2014 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.
 
 #ifndef V8_FACTORY_H_
 #define V8_FACTORY_H_
 
 #include "src/globals.h"
 #include "src/isolate.h"
 #include "src/messages.h"
@@ skipping 278 matching lines @@
                                    Handle<ScopeInfo> scope_info);
 
   // Create an empty script context table.
   Handle<ScriptContextTable> NewScriptContextTable();
 
   // Create a module context.
   Handle<Context> NewModuleContext(Handle<Module> module,
                                    Handle<JSFunction> function,
                                    Handle<ScopeInfo> scope_info);
 
-  // Create a function context.
-  Handle<Context> NewFunctionContext(int length, Handle<JSFunction> function);
+  // Create a function or eval context.

[adamk, 2016/12/14 12:23:31]

Can you mention here that scope_type should be one of FUNCTION_SCOPE/EVAL_SCOPE?

[Dan Ehrenberg, 2016/12/14 22:53:30]

There are tons of places where scope_type is an instance variable or argument.
Should I put that everywhere? I thought it might be enough to have the DCHECKs.

[adamk, 2016/12/15 08:46:52]

I commented on this case just because it happened to have a comment already. I
don't think you need to sprinkle this comment everywhere.

Also note that UNREACHABLE() is a CHECK, not a DCHECK (I think that's OK, just
want to make sure you're aware).

+  Handle<Context> NewFunctionContext(int length, Handle<JSFunction> function,
+                                     ScopeType scope_type);
 
   // Create a catch context.
   Handle<Context> NewCatchContext(Handle<JSFunction> function,
                                   Handle<Context> previous,
                                   Handle<ScopeInfo> scope_info,
                                   Handle<String> name,
                                   Handle<Object> thrown_object);
 
   // Create a 'with' context.
   Handle<Context> NewWithContext(Handle<JSFunction> function,
@@ skipping 495 matching lines @@
   void SetStrictFunctionInstanceDescriptor(Handle<Map> map,
                                            FunctionMode function_mode);
 
   void SetClassFunctionInstanceDescriptor(Handle<Map> map);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_FACTORY_H_