[Tracing] Implement IC statistics in tracing.

src/ic/ic-stats.h

+// Copyright 2016 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_IC_IC_STATS_H_
+#define V8_IC_IC_STATS_H_
+
+#include <memory>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+#include "src/base/atomicops.h"
+#include "src/base/lazy-instance.h"
+
+namespace v8 {
+
+namespace tracing {
+class TracedValue;
+}
+
+namespace internal {
+
+class JSFunction;
+class Object;
+
+struct ICInfo {
+  ICInfo();
+  void Reset();
+  void AppendToTracedValue(v8::tracing::TracedValue* value) const;
+  std::string type;
+  std::string function_name;
+  int offset;

[Camillo Bruni, 2016/12/02 12:12:55]

rename to script_offset

[lpy, 2016/12/05 17:49:11]

Done.

+  const char* script_name;
+  int line_num;
+  unsigned constructor;

[Camillo Bruni, 2016/12/02 12:12:55]

bool is_constructor

[lpy, 2016/12/05 17:49:11]

Done.

+  std::string state;
+  // Address of the map.
+  void* map;
+  // Indicate whether map is a dictionary map.
+  unsigned dict;

[Camillo Bruni, 2016/12/02 12:12:55]

this should be bool I guess (also maybe rename it to something more clear like
is_dictionary_map)

[lpy, 2016/12/05 17:49:11]

Done.

+  // Number of own descriptors.
+  unsigned own;

[Camillo Bruni, 2016/12/02 12:12:55]

please rename to: number_of_own_descriptors (or a short form of it).

[lpy, 2016/12/05 17:49:11]

Done.

+  std::string instance_type;
+};
+
+class ICStats {
+ public:
+  const int MAX_IC_INFO = 4096;
+
+  ICStats();
+  void Dump();
+  void Begin();
+  void End();
+  void Reset();
+  V8_INLINE ICInfo& Current() {
+    DCHECK(pos_ >= 0 && pos_ < MAX_IC_INFO);
+    return ic_infos_[pos_];
+  }
+  const char* GetOrCacheScriptName(Object* obj);
+  std::string& GetOrCacheFunctionName(JSFunction* function);
+  V8_INLINE static ICStats* instance() { return instance_.Pointer(); }
+
+ private:
+  static base::LazyInstance<ICStats>::type instance_;
+  base::Atomic32 being_used_;

[Camillo Bruni, 2016/12/02 12:12:55]

How about "enabled"?

[lpy, 2016/12/05 17:49:11]

Done.

+  std::vector<ICInfo> ic_infos_;
+  std::unordered_map<Object*, std::unique_ptr<char[]>> script_name_map_;
+  std::unordered_map<JSFunction*, std::string> function_name_map_;

[Camillo Bruni, 2016/12/02 12:12:55]

Did you try running this on a big website and see if the memory consumption
isn't killing us?
http://edition.cnn.com/ is reasonably complex and good old
http://facebook.com/shakira?

[lpy, 2016/12/05 17:49:11]

Thanks for the advice, will try it with Chrome TOT and let you know.

+  int pos_;
+};
+
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_IC_IC_STATS_H_