Add a flag to trace heap object stats on GC.

BUG=

Review URL: https://codereview.chromium.org/1094613002

Cr-Commit-Position: refs/heads/master@{#27886}

src/flag-definitions.h

@@ -626,6 +626,9 @@ DEFINE_BOOL(trace_incremental_marking, false,
             "trace progress of the incremental marking")
 DEFINE_BOOL(track_gc_object_stats, false,
             "track object counts and memory usage")
+DEFINE_BOOL(trace_gc_object_stats, false,
+            "trace object counts and memory usage")
+DEFINE_IMPLICATION(trace_gc_object_stats, track_gc_object_stats)
 DEFINE_BOOL(track_detached_contexts, true,
             "track native contexts that are expected to be garbage collected")
 DEFINE_BOOL(trace_detached_contexts, false,

src/heap/heap.cc

@@ -6253,12 +6253,57 @@ void Heap::ClearObjectStats(bool clear_last_time_stats) {
 }
 
 
-static base::LazyMutex checkpoint_object_stats_mutex = LAZY_MUTEX_INITIALIZER;
+static base::LazyMutex object_stats_mutex = LAZY_MUTEX_INITIALIZER;
+
+
+static void TraceObjectStat(const char* name, int count, int size) {
+  if (size > 0) {
+    PrintF("%40s\tcount= %6d\t size= %6d kb\n", name, count, size);
+  }
+}
+
+
+void Heap::TraceObjectStats() {
+  base::LockGuard<base::Mutex> lock_guard(object_stats_mutex.Pointer());
+  int index;
+  int count;
+  int size;
+  int total_size = 0;
+#define TRACE_OBJECT_COUNT(name)                     \
+  count = static_cast<int>(object_counts_[name]);    \
+  size = static_cast<int>(object_sizes_[name]) / KB; \
+  total_size += size;                                \
+  TraceObjectStat(#name, count, size);
+  INSTANCE_TYPE_LIST(TRACE_OBJECT_COUNT)
+#undef TRACE_OBJECT_COUNT
+#define TRACE_OBJECT_COUNT(name)                      \
+  index = FIRST_CODE_KIND_SUB_TYPE + Code::name;      \
+  count = static_cast<int>(object_counts_[index]);    \
+  size = static_cast<int>(object_sizes_[index]) / KB; \
+  TraceObjectStat("CODE_" #name, count, size);
+  CODE_KIND_LIST(TRACE_OBJECT_COUNT)
+#undef TRACE_OBJECT_COUNT
+#define TRACE_OBJECT_COUNT(name)                      \
+  index = FIRST_FIXED_ARRAY_SUB_TYPE + name;          \
+  count = static_cast<int>(object_counts_[index]);    \
+  size = static_cast<int>(object_sizes_[index]) / KB; \
+  TraceObjectStat("FIXED_ARRAY_" #name, count, size);
+  FIXED_ARRAY_SUB_INSTANCE_TYPE_LIST(TRACE_OBJECT_COUNT)
+#undef TRACE_OBJECT_COUNT
+#define TRACE_OBJECT_COUNT(name)                                              \
+  index =                                                                     \
+      FIRST_CODE_AGE_SUB_TYPE + Code::k##name##CodeAge - Code::kFirstCodeAge; \
+  count = static_cast<int>(object_counts_[index]);                            \
+  size = static_cast<int>(object_sizes_[index]) / KB;                         \
+  TraceObjectStat("CODE_AGE_" #name, count, size);
+  CODE_AGE_LIST_COMPLETE(TRACE_OBJECT_COUNT)
+#undef TRACE_OBJECT_COUNT
+  PrintF("Total size= %d kb\n", total_size);
+}
 
 
 void Heap::CheckpointObjectStats() {
-  base::LockGuard<base::Mutex> lock_guard(
-      checkpoint_object_stats_mutex.Pointer());
+  base::LockGuard<base::Mutex> lock_guard(object_stats_mutex.Pointer());
   Counters* counters = isolate()->counters();
 #define ADJUST_LAST_TIME_OBJECT_COUNT(name)              \
   counters->count_of_##name()->Increment(                \

src/heap/heap.h

@@ -1429,6 +1429,7 @@ class Heap {
     object_sizes_[FIRST_FIXED_ARRAY_SUB_TYPE + array_sub_type] += size;
   }
 
+  void TraceObjectStats();
   void CheckpointObjectStats();
 
   // We don't use a LockGuard here since we want to lock the heap

src/heap/mark-compact.cc

@@ -2385,6 +2385,9 @@ void MarkCompactCollector::AfterMarking() {
   }
 
   if (FLAG_track_gc_object_stats) {
+    if (FLAG_trace_gc_object_stats) {
+      heap()->TraceObjectStats();
+    }
     heap()->CheckpointObjectStats();
   }
 }