[heap] Remove --heap-stats.

Bug: 
Change-Id: I53b68e8a4200a87d9f14b9540b52cab316678b2d
Reviewed-on: https://chromium-review.googlesource.com/836593
Commit-Queue: Hannes Payer <hpayer@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50233}

src/flag-definitions.h

@@ -1065,7 +1065,6 @@ DEFINE_BOOL(trace_contexts, false, "trace contexts operations")
 
 // heap.cc
 DEFINE_BOOL(gc_verbose, false, "print stuff during garbage collection")
-DEFINE_BOOL(heap_stats, false, "report heap statistics before and after GC")
 DEFINE_BOOL(code_stats, false, "report code statistics after GC")
 DEFINE_BOOL(print_handles, false, "report handles after GC")
 DEFINE_BOOL(check_handle_count, false,

src/heap/heap.cc

@@ -363,17 +363,6 @@ void Heap::SetGCState(HeapState state) {
   gc_state_ = state;
 }
 
-void Heap::ReportStatisticsBeforeGC() {
-#ifdef DEBUG
-  if (FLAG_heap_stats) {
-    new_space_->CollectStatistics();
-    ReportHeapStatistics("Before GC");
-    new_space_->ClearHistograms();
-  }
-#endif  // DEBUG
-}
-
-
 void Heap::PrintShortHeapStatistics() {
   if (!FLAG_trace_gc_verbose) return;
   PrintIsolate(isolate_, "Memory allocator,   used: %6" PRIuS
@@ -432,12 +421,6 @@ void Heap::PrintShortHeapStatistics() {
 }
 
 void Heap::ReportStatisticsAfterGC() {
-#if defined(DEBUG)
-  if (FLAG_heap_stats) {
-    new_space_->CollectStatistics();
-    ReportHeapStatistics("After GC");
-  }
-#endif  // DEBUG
   for (int i = 0; i < static_cast<int>(v8::Isolate::kUseCounterFeatureCount);
        ++i) {
     int count = deferred_counters_[i];
@@ -616,8 +599,6 @@ void Heap::GarbageCollectionPrologue() {
   DCHECK(!AllowHeapAllocation::IsAllowed() && gc_state_ == NOT_IN_GC);
 
   if (FLAG_gc_verbose) Print();
-
-  ReportStatisticsBeforeGC();
 #endif  // DEBUG
 
   if (new_space_->IsAtMaximumCapacity()) {
@@ -4575,37 +4556,6 @@ void Heap::ReportCodeStatistics(const char* title) {
   CodeStatistics::ReportCodeStatistics(isolate());
 }
 
-
-// This function expects that NewSpace's allocated objects histogram is
-// populated (via a call to CollectStatistics or else as a side effect of a
-// just-completed scavenge collection).
-void Heap::ReportHeapStatistics(const char* title) {
-  USE(title);
-  PrintF(">>>>>> =============== %s (%d) =============== >>>>>>\n", title,
-         gc_count_);
-  PrintF("old_generation_allocation_limit_ %" PRIuS "\n",
-         old_generation_allocation_limit_);
-
-  PrintF("\n");
-  PrintF("Number of handles : %d\n", HandleScope::NumberOfHandles(isolate_));
-  isolate_->global_handles()->PrintStats();
-  PrintF("\n");
-
-  PrintF("Heap statistics : ");
-  memory_allocator()->ReportStatistics();
-  PrintF("To space : ");
-  new_space_->ReportStatistics();
-  PrintF("Old space : ");
-  old_space_->ReportStatistics();
-  PrintF("Code space : ");
-  code_space_->ReportStatistics();
-  PrintF("Map space : ");
-  map_space_->ReportStatistics();
-  PrintF("Large object space : ");
-  lo_space_->ReportStatistics();
-  PrintF(">>>>>> ========================================= >>>>>>\n");
-}
-
 #endif  // DEBUG
 
 const char* Heap::GarbageCollectionReasonToString(

src/heap/heap.h

@@ -1641,8 +1641,7 @@ class Heap {
   void Print();
   void PrintHandles();
 
-  // Report heap statistics.
-  void ReportHeapStatistics(const char* title);
+  // Report code statistics.
   void ReportCodeStatistics(const char* title);
 #endif
   void* GetRandomMmapAddr() {
@@ -1871,8 +1870,7 @@ class Heap {
   // the old space.
   void EvaluateOldSpaceLocalPretenuring(uint64_t size_of_objects_before_gc);
 
-  // Record statistics before and after garbage collection.
-  void ReportStatisticsBeforeGC();
+  // Record statistics after garbage collection.
   void ReportStatisticsAfterGC();
 
   // Creates and installs the full-sized number string cache.

src/heap/scavenger-inl.h

@@ -58,8 +58,6 @@ bool Scavenger::MigrateObject(Map* map, HeapObject* source, HeapObject* target,
   }
 
   if (V8_UNLIKELY(is_logging_)) {
-    // Update NewSpace stats if necessary.
-    RecordCopiedObject(target);
     heap()->OnMoveEvent(target, source, size);
   }
 

src/heap/scavenger.cc

@@ -153,18 +153,6 @@ void Scavenger::Process(OneshotBarrier* barrier) {
   } while (!done);
 }
 
-void Scavenger::RecordCopiedObject(HeapObject* obj) {
-#ifdef DEBUG
-  if (FLAG_heap_stats) {
-    if (heap()->new_space()->Contains(obj)) {
-      heap()->new_space()->RecordAllocation(obj);
-    } else {
-      heap()->new_space()->RecordPromotion(obj);
-    }
-  }
-#endif
-}
-
 void Scavenger::Finalize() {
   heap()->MergeAllocationSitePretenuringFeedback(local_pretenuring_feedback_);
   heap()->IncrementSemiSpaceCopiedObjectSize(copied_size_);

src/heap/scavenger.h

@@ -92,8 +92,6 @@ class Scavenger {
 
   void IterateAndScavengePromotedObject(HeapObject* target, int size);
 
-  void RecordCopiedObject(HeapObject* obj);
-
   static inline bool ContainsOnlyData(VisitorId visitor_id);
 
   Heap* const heap_;

src/heap/spaces.cc

@@ -2638,44 +2638,6 @@ static void ReportHistogram(Isolate* isolate, bool print_spill) {
 }
 #endif  // DEBUG
 
-// Support for statistics gathering for --heap-stats.
-void NewSpace::ClearHistograms() {
-  for (int i = 0; i <= LAST_TYPE; i++) {
-    allocated_histogram_[i].clear();
-    promoted_histogram_[i].clear();
-  }
-}
-
-
-// Because the copying collector does not touch garbage objects, we iterate
-// the new space before a collection to get a histogram of allocated objects.
-void NewSpace::CollectStatistics() {
-  ClearHistograms();
-  SemiSpaceIterator it(this);
-  for (HeapObject* obj = it.Next(); obj != nullptr; obj = it.Next())
-    RecordAllocation(obj);
-}
-
-void NewSpace::ReportStatistics() {
-#ifdef DEBUG
-  if (FLAG_heap_stats) {
-    float pct = static_cast<float>(Available()) / TotalCapacity();
-    PrintF("  capacity: %" PRIuS ", available: %" PRIuS ", %%%d\n",
-           TotalCapacity(), Available(), static_cast<int>(pct * 100));
-    PrintF("\n  Object Histogram:\n");
-    for (int i = 0; i <= LAST_TYPE; i++) {
-      if (allocated_histogram_[i].number() > 0) {
-        PrintF("    %-34s%10d (%10d bytes)\n", allocated_histogram_[i].name(),
-               allocated_histogram_[i].number(),
-               allocated_histogram_[i].bytes());
-      }
-    }
-    PrintF("\n");
-  }
-#endif  // DEBUG
-}
-
-
 void NewSpace::RecordAllocation(HeapObject* obj) {
   InstanceType type = obj->map()->instance_type();
   DCHECK(0 <= type && type <= LAST_TYPE);

src/heap/spaces.h

@@ -2716,13 +2716,6 @@ class NewSpace : public SpaceWithLinearArea {
   void Print() override { to_space_.Print(); }
 #endif
 
-  // Iterates the active semispace to collect statistics.
-  void CollectStatistics();
-  // Reports previously collected statistics of the active semispace.
-  void ReportStatistics();
-  // Clears previously collected statistics.
-  void ClearHistograms();
-
   // Record the allocation or promotion of a heap object.  Note that we don't
   // record every single allocation, but only those that happen in the
   // to space during a scavenge GC.

test/mjsunit/regress/regress-2646.js

@@ -25,8 +25,6 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-// Flags: --heap-stats
-
 var expectedItemsCount = 10000,
     itemSize = 5,
     heap = new ArrayBuffer(expectedItemsCount * itemSize * 8),

test/mjsunit/regress/regress-370827.js

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --allow-natives-syntax --expose-gc --heap-stats
+// Flags: --allow-natives-syntax --expose-gc
 
 function g(dummy, x) {
   var start = "";