From cd819760653545eda593c8b6ca5b39782efbaf8f Mon Sep 17 00:00:00 2001
From: "alexeif@chromium.org"
 <alexeif@chromium.org@ce2b1a6d-e550-0410-aec6-3dcde31c8c00>
Date: Tue, 13 Mar 2012 15:42:26 +0000
Subject: [PATCH] Store entry id as 32-bit int.

BUG=
TEST=

Review URL: https://chromiumcodereview.appspot.com/9695046

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11029 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
---
 src/profile-generator-inl.h |  9 ---------
 src/profile-generator.cc    | 13 ++++---------
 src/profile-generator.h     |  7 ++-----
 3 files changed, 6 insertions(+), 23 deletions(-)

diff --git a/src/profile-generator-inl.h b/src/profile-generator-inl.h
index d967ed3..65369be 100644
--- a/src/profile-generator-inl.h
+++ b/src/profile-generator-inl.h
@@ -114,15 +114,6 @@ int V8HeapExplorer::GetGcSubrootOrder(HeapObject* subroot) {
       HeapObjectsMap::kObjectIdStep);
 }
 
-
-SnapshotObjectId HeapEntry::id() {
-  union {
-    Id stored_id;
-    SnapshotObjectId returned_id;
-  } id_adaptor = {id_};
-  return id_adaptor.returned_id;
-}
-
 } }  // namespace v8::internal
 
 #endif  // V8_PROFILE_GENERATOR_INL_H_
diff --git a/src/profile-generator.cc b/src/profile-generator.cc
index ca97565..2d0984e 100644
--- a/src/profile-generator.cc
+++ b/src/profile-generator.cc
@@ -978,12 +978,7 @@ void HeapEntry::Init(HeapSnapshot* snapshot,
   children_count_ = children_count;
   retainers_count_ = retainers_count;
   dominator_ = NULL;
-
-  union {
-    SnapshotObjectId set_id;
-    Id stored_id;
-  } id_adaptor = {id};
-  id_ = id_adaptor.stored_id;
+  id_ = id;
 }
 
 
@@ -1113,7 +1108,7 @@ template <size_t ptr_size> struct SnapshotSizeConstants;
 
 template <> struct SnapshotSizeConstants<4> {
   static const int kExpectedHeapGraphEdgeSize = 12;
-  static const int kExpectedHeapEntrySize = 36;
+  static const int kExpectedHeapEntrySize = 32;
   static const size_t kMaxSerializableSnapshotRawSize = 256 * MB;
 };
 
@@ -1139,10 +1134,10 @@ HeapSnapshot::HeapSnapshot(HeapSnapshotsCollection* collection,
       natives_root_entry_(NULL),
       raw_entries_(NULL),
       entries_sorted_(false) {
-  STATIC_ASSERT(
+  STATIC_CHECK(
       sizeof(HeapGraphEdge) ==
       SnapshotSizeConstants<kPointerSize>::kExpectedHeapGraphEdgeSize);
-  STATIC_ASSERT(
+  STATIC_CHECK(
       sizeof(HeapEntry) ==
       SnapshotSizeConstants<kPointerSize>::kExpectedHeapEntrySize);
   for (int i = 0; i < VisitorSynchronization::kNumberOfSyncTags; ++i) {
diff --git a/src/profile-generator.h b/src/profile-generator.h
index fadae7e..d9a1319 100644
--- a/src/profile-generator.h
+++ b/src/profile-generator.h
@@ -544,7 +544,7 @@ class HeapEntry BASE_EMBEDDED {
   Type type() { return static_cast<Type>(type_); }
   const char* name() { return name_; }
   void set_name(const char* name) { name_ = name; }
-  inline SnapshotObjectId id();
+  inline SnapshotObjectId id() { return id_; }
   int self_size() { return self_size_; }
   int retained_size() { return retained_size_; }
   void add_retained_size(int size) { retained_size_ += size; }
@@ -608,12 +608,9 @@ class HeapEntry BASE_EMBEDDED {
     int ordered_index_;  // Used during dominator tree building.
     int retained_size_;  // At that moment, there is no retained size yet.
   };
+  SnapshotObjectId id_;
   HeapEntry* dominator_;
   HeapSnapshot* snapshot_;
-  struct Id {
-    uint32_t id1_;
-    uint32_t id2_;
-  } id_;  // This is to avoid extra padding of 64-bit value.
   const char* name_;
 
   DISALLOW_COPY_AND_ASSIGN(HeapEntry);
-- 
2.7.4