[tracing] Optimize StackFrameDeduplicator.

base/trace_event/memory_usage_estimator.h

 // Copyright 2016 The Chromium 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 BASE_TRACE_EVENT_MEMORY_USAGE_ESTIMATOR_H_
 #define BASE_TRACE_EVENT_MEMORY_USAGE_ESTIMATOR_H_
 
 #include <stdint.h>
 
 #include <array>
 #include <deque>
 #include <list>
 #include <map>
 #include <memory>
 #include <queue>
 #include <set>
 #include <stack>
 #include <string>
 #include <type_traits>
 #include <unordered_map>
 #include <unordered_set>
 #include <vector>
 
 #include "base/base_export.h"
+#include "base/containers/flat_map.h"
+#include "base/containers/flat_set.h"
 #include "base/containers/linked_list.h"
 #include "base/strings/string16.h"
 
 // Composable memory usage estimators.
 //
 // This file defines set of EstimateMemoryUsage(object) functions that return
 // approximate memory usage of their argument.
 //
 // The ultimate goal is to make memory usage estimation for a class simply a
 // matter of aggregating EstimateMemoryUsage() results over all fields.
@@ skipping 108 matching lines @@
 
 template <class T, class C>
 size_t EstimateMemoryUsage(const std::queue<T, C>& queue);
 
 template <class T, class C>
 size_t EstimateMemoryUsage(const std::priority_queue<T, C>& queue);
 
 template <class T, class C>
 size_t EstimateMemoryUsage(const std::stack<T, C>& stack);
 
+template <class T, class C>
+size_t EstimateMemoryUsage(const base::flat_set<T, C>& set);
+
+template <class K, class V, class C>
+size_t EstimateMemoryUsage(const base::flat_map<K, V, C>& map);
+
 // TODO(dskiba):
 //   std::forward_list
 
 // Definitions
 
 namespace internal {
 
 // HasEMU<T>::value is true iff EstimateMemoryUsage(T) is available.
 // (This is the default version, which is false.)
 template <class T, class X = void>
@@ skipping 372 matching lines @@
 template <class T, class C>
 size_t EstimateMemoryUsage(const std::priority_queue<T, C>& queue) {
   return EstimateMemoryUsage(internal::GetUnderlyingContainer(queue));
 }
 
 template <class T, class C>
 size_t EstimateMemoryUsage(const std::stack<T, C>& stack) {
   return EstimateMemoryUsage(internal::GetUnderlyingContainer(stack));
 }
 
+// Flat containers
+
+template <class T, class C>
+size_t EstimateMemoryUsage(const base::flat_set<T, C>& set) {
+  using value_type = typename base::flat_set<T, C>::value_type;
+  return sizeof(value_type) * set.capacity() + EstimateIterableMemoryUsage(set);
+}
+
+template <class K, class V, class C>
+size_t EstimateMemoryUsage(const base::flat_map<K, V, C>& map) {
+  using value_type = typename base::flat_map<K, V, C>::value_type;
+  return sizeof(value_type) * map.capacity() + EstimateIterableMemoryUsage(map);
+}
+
 }  // namespace trace_event
 }  // namespace base
 
 #endif  // BASE_TRACE_EVENT_MEMORY_USAGE_ESTIMATOR_H_