AppList Performance Optimization 2

ui/app_list/search/mixer.cc

Index: ui/app_list/search/mixer.cc
diff --git a/ui/app_list/search/mixer.cc b/ui/app_list/search/mixer.cc
index 0e8cdb33e00ed17b979d39ed499f39db425ea793..78db4de53756c8dae7b7a17c6e5c776e3055460d 100644
--- a/ui/app_list/search/mixer.cc
+++ b/ui/app_list/search/mixer.cc
@@ -28,8 +28,7 @@ void UpdateResult(const SearchResult& source, SearchResult* target) {
 
 }  // namespace
 
-Mixer::SortData::SortData() : result(NULL), score(0.0) {
-}
+Mixer::SortData::SortData() : result(nullptr), score(0.0) {}
 
 Mixer::SortData::SortData(SearchResult* result, double score)
     : result(result), score(score) {
@@ -47,21 +46,22 @@ class Mixer::Group {
       : max_results_(max_results), multiplier_(multiplier) {}
   ~Group() {}
 
-  void AddProvider(SearchProvider* provider) { providers_.push_back(provider); }
+  void AddProvider(SearchProvider* provider) {
+    providers_.emplace_back(provider);
+  }
 
   void FetchResults(bool is_voice_query, const KnownResults& known_results) {
     results_.clear();
 
     for (const SearchProvider* provider : providers_) {
-      for (SearchResult* result : provider->results()) {
+      for (const auto& result : provider->results()) {
         DCHECK(!result->id().empty());
 
         // We cannot rely on providers to give relevance scores in the range
         // [0.0, 1.0] (e.g., PeopleProvider directly gives values from the
         // Google+ API). Clamp to that range.
-        double relevance = std::min(std::max(result->relevance(), 0.0), 1.0);
-
-        double multiplier = multiplier_;
+        const double relevance =
+            std::min(std::max(result->relevance(), 0.0), 1.0);
         double boost = 0.0;
 
         // Recommendations should not be affected by query-to-launch correlation
@@ -97,7 +97,7 @@ class Mixer::Group {
             boost += 4.0;
         }
 
-        results_.push_back(SortData(result, relevance * multiplier + boost));
+        results_.emplace_back(result.get(), relevance * multiplier_ + boost);
       }
     }
 
@@ -145,7 +145,7 @@ void Mixer::MixAndPublish(bool is_voice_query,
   // Add results from each group. Limit to the maximum number of results in each
   // group.
   for (const Group* group : groups_) {
-    size_t num_results =
+    const size_t num_results =
         std::min(group->results().size(), group->max_results());
     results.insert(results.end(), group->results().begin(),
                    group->results().begin() + num_results);
@@ -157,8 +157,8 @@ void Mixer::MixAndPublish(bool is_voice_query,
   RemoveDuplicates(&results);
   std::sort(results.begin(), results.end());
 
-  if (results.size() < num_max_results) {
-    size_t original_size = results.size();
+  const size_t original_size = results.size();
+  if (original_size < num_max_results) {
     // We didn't get enough results. Insert all the results again, and this
     // time, do not limit the maximum number of results from each group. (This
     // will result in duplicates, which will be removed by RemoveDuplicates.)
@@ -192,7 +192,7 @@ void Mixer::Publish(const SortedResults& new_results,
   // meaningful indexes.
   auto current_results = ui_results->RemoveAll();
   std::map<std::string, std::unique_ptr<SearchResult>> ui_results_map;
-  for (std::unique_ptr<SearchResult>& ui_result : current_results)
+  for (auto& ui_result : current_results)
     ui_results_map[ui_result->id()] = std::move(ui_result);
 
   // Add items back to |ui_results| in the order of |new_results|.
@@ -227,12 +227,10 @@ void Mixer::RemoveDuplicates(SortedResults* results) {
 
   std::set<std::string> id_set;
   for (const SortData& sort_data : *results) {
-    const std::string& id = sort_data.result->id();
-    if (id_set.find(id) != id_set.end())
+    if (!id_set.insert(sort_data.result->id()).second)
       continue;
 
-    id_set.insert(id);
-    final.push_back(sort_data);
+    final.emplace_back(sort_data);
   }
 
   results->swap(final);