Show names of the context fields in heap snapshot.

src/profile-generator.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2050 matching lines @@
     if (obj->IsConsString()) {
       ConsString* cs = ConsString::cast(obj);
       SetInternalReference(obj, entry, 1, cs->first());
       SetInternalReference(obj, entry, 2, cs->second());
     }
     if (obj->IsSlicedString()) {
       SlicedString* ss = SlicedString::cast(obj);
       SetInternalReference(obj, entry, "parent", ss->parent());
     }
     extract_indexed_refs = false;
-  } else if (obj->IsGlobalContext()) {
+  } else if (obj->IsContext()) {
     Context* context = Context::cast(obj);
-    TagObject(context->jsfunction_result_caches(),
-              "(context func. result caches)");
-    TagObject(context->normalized_map_cache(), "(context norm. map cache)");
-    TagObject(context->runtime_context(), "(runtime context)");
-    TagObject(context->data(), "(context data)");
-    for (int i = Context::FIRST_WEAK_SLOT;
-         i < Context::GLOBAL_CONTEXT_SLOTS;
-         ++i) {
-      SetWeakReference(obj, entry,
-                       i, context->get(i),
-                       FixedArray::OffsetOfElementAt(i));
+#define EXTRACT_CONTEXT_FIELD(index, type, name) \
+    SetInternalReference(context, entry, #name, context->get(Context::index), \
+        FixedArray::OffsetOfElementAt(Context::index));
+    EXTRACT_CONTEXT_FIELD(CLOSURE_INDEX, JSFunction, closure);
+    EXTRACT_CONTEXT_FIELD(PREVIOUS_INDEX, Context, previous);
+    EXTRACT_CONTEXT_FIELD(EXTENSION_INDEX, Object, extension);
+    EXTRACT_CONTEXT_FIELD(GLOBAL_INDEX, GlobalObject, global);
+    if (obj->IsGlobalContext()) {
+      TagObject(context->jsfunction_result_caches(),
+                "(context func. result caches)");
+      TagObject(context->normalized_map_cache(), "(context norm. map cache)");
+      TagObject(context->runtime_context(), "(runtime context)");
+      TagObject(context->data(), "(context data)");
+      GLOBAL_CONTEXT_FIELDS(EXTRACT_CONTEXT_FIELD);
+#undef EXTRACT_CONTEXT_FIELD
+      for (int i = Context::FIRST_WEAK_SLOT;
+           i < Context::GLOBAL_CONTEXT_SLOTS;
+           ++i) {
+        SetWeakReference(obj, entry,
+                         i, context->get(i),
+                         FixedArray::OffsetOfElementAt(i));
+      }
     }
   } else if (obj->IsMap()) {
     Map* map = Map::cast(obj);
     SetInternalReference(obj, entry,
                          "prototype", map->prototype(), Map::kPrototypeOffset);
     SetInternalReference(obj, entry,
                          "constructor", map->constructor(),
                          Map::kConstructorOffset);
     if (!map->instance_descriptors()->IsEmpty()) {
       TagObject(map->instance_descriptors(), "(map descriptors)");
@@ skipping 86 matching lines @@
     obj->Iterate(&refs_extractor);
   }
 }
 
 
 void V8HeapExplorer::ExtractClosureReferences(JSObject* js_obj,
                                               HeapEntry* entry) {
   if (!js_obj->IsJSFunction()) return;
 
   JSFunction* func = JSFunction::cast(js_obj);
-  Context* context = func->context()->declaration_context();
-  ScopeInfo* scope_info = context->closure()->shared()->scope_info();
-
   if (func->shared()->bound()) {
     FixedArray* bindings = func->function_bindings();
     SetNativeBindReference(js_obj, entry, "bound_this",
                            bindings->get(JSFunction::kBoundThisIndex));
     SetNativeBindReference(js_obj, entry, "bound_function",
                            bindings->get(JSFunction::kBoundFunctionIndex));
     for (int i = JSFunction::kBoundArgumentsStartIndex;
          i < bindings->length(); i++) {
       const char* reference_name = collection_->names()->GetFormatted(
           "bound_argument_%d",
           i - JSFunction::kBoundArgumentsStartIndex);
       SetNativeBindReference(js_obj, entry, reference_name,
                              bindings->get(i));
     }
   } else {
+    Context* context = func->context()->declaration_context();
+    ScopeInfo* scope_info = context->closure()->shared()->scope_info();
     // Add context allocated locals.
     int context_locals = scope_info->ContextLocalCount();
     for (int i = 0; i < context_locals; ++i) {
       String* local_name = scope_info->ContextLocalName(i);
       int idx = Context::MIN_CONTEXT_SLOTS + i;
       SetClosureReference(js_obj, entry, local_name, context->get(idx));
     }
 
     // Add function variable.
     if (scope_info->HasFunctionName()) {
@@ skipping 1750 matching lines @@
 
 
 void HeapSnapshotJSONSerializer::SortHashMap(
     HashMap* map, List<HashMap::Entry*>* sorted_entries) {
   for (HashMap::Entry* p = map->Start(); p != NULL; p = map->Next(p))
     sorted_entries->Add(p);
   sorted_entries->Sort(SortUsingEntryValue);
 }
 
 } }  // namespace v8::internal