Adds support for collecting statistics about code and its metadata.

src/heap/spaces.cc

 // Copyright 2011 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.
 
 #include "src/heap/spaces.h"
 
 #include "src/base/bits.h"
 #include "src/base/platform/platform.h"
 #include "src/base/platform/semaphore.h"
 #include "src/full-codegen/full-codegen.h"
@@ skipping 1999 matching lines @@
   Initialize(space->bottom(), space->top());
 }
 
 
 void SemiSpaceIterator::Initialize(Address start, Address end) {
   SemiSpace::AssertValidRange(start, end);
   current_ = start;
   limit_ = end;
 }
 
-
 #ifdef DEBUG
 // heap_histograms is shared, always clear it before using it.
 static void ClearHistograms(Isolate* isolate) {
 // We reset the name each time, though it hasn't changed.
 #define DEF_TYPE_NAME(name) isolate->heap_histograms()[name].set_name(#name);
   INSTANCE_TYPE_LIST(DEF_TYPE_NAME)
 #undef DEF_TYPE_NAME
 
 #define CLEAR_HISTOGRAM(name) isolate->heap_histograms()[name].clear();
   INSTANCE_TYPE_LIST(CLEAR_HISTOGRAM)
 #undef CLEAR_HISTOGRAM
 
   isolate->js_spill_information()->Clear();
 }
 
 
 static void ClearCodeKindStatistics(int* code_kind_statistics) {
-  for (int i = 0; i < Code::NUMBER_OF_KINDS; i++) {
+  for (int i = 0; i < AbstractCode::NUMBER_OF_KINDS; i++) {
     code_kind_statistics[i] = 0;
   }
 }
-
-
 static void ReportCodeKindStatistics(int* code_kind_statistics) {
   PrintF("\n   Code kind histograms: \n");
-  for (int i = 0; i < Code::NUMBER_OF_KINDS; i++) {
+  for (int i = 0; i < AbstractCode::NUMBER_OF_KINDS; i++) {
     if (code_kind_statistics[i] > 0) {
       PrintF("     %-20s: %10d bytes\n",
-             Code::Kind2String(static_cast<Code::Kind>(i)),
+             AbstractCode::Kind2String(static_cast<AbstractCode::Kind>(i)),
              code_kind_statistics[i]);
     }
   }
   PrintF("\n");
 }
 
-
 static int CollectHistogramInfo(HeapObject* obj) {
   Isolate* isolate = obj->GetIsolate();
   InstanceType type = obj->map()->instance_type();
   DCHECK(0 <= type && type <= LAST_TYPE);
   DCHECK(isolate->heap_histograms()[type].name() != NULL);
   isolate->heap_histograms()[type].increment_number(1);
   isolate->heap_histograms()[type].increment_bytes(obj->Size());
 
   if (FLAG_collect_heap_spill_statistics && obj->IsJSObject()) {
     JSObject::cast(obj)
@@ skipping 675 matching lines @@
            (size_in_bytes <= free_list_.Available()));
     return free_list_.Allocate(size_in_bytes);
   }
 
   // If sweeper threads are active, wait for them at that point and steal
   // elements form their free-lists. Allocation may still fail their which
   // would indicate that there is not enough memory for the given allocation.
   return SweepAndRetryAllocation(size_in_bytes);
 }
 
-
 #ifdef DEBUG
 void PagedSpace::ReportCodeStatistics(Isolate* isolate) {
   CommentStatistic* comments_statistics =
       isolate->paged_space_comments_statistics();
   ReportCodeKindStatistics(isolate->code_kind_statistics());
+  PrintF("code + metadata size    : %10d bytes\n",
+         isolate->code_and_metadata_size());
+  PrintF("bytecode + metadata size: %10d bytes\n",
+         isolate->bytecode_and_metadata_size());
   PrintF(
       "Code comment statistics (\"   [ comment-txt   :    size/   "
       "count  (average)\"):\n");
   for (int i = 0; i <= CommentStatistic::kMaxComments; i++) {
     const CommentStatistic& cs = comments_statistics[i];
     if (cs.size > 0) {
       PrintF("   %-30s: %10d/%6d     (%d)\n", cs.comment, cs.size, cs.count,
              cs.size / cs.count);
     }
   }
   PrintF("\n");
 }
 
-
 void PagedSpace::ResetCodeStatistics(Isolate* isolate) {
   CommentStatistic* comments_statistics =
       isolate->paged_space_comments_statistics();
   ClearCodeKindStatistics(isolate->code_kind_statistics());
   for (int i = 0; i < CommentStatistic::kMaxComments; i++) {
     comments_statistics[i].Clear();
   }
   comments_statistics[CommentStatistic::kMaxComments].comment = "Unknown";
   comments_statistics[CommentStatistic::kMaxComments].size = 0;
   comments_statistics[CommentStatistic::kMaxComments].count = 0;
@@ skipping 55 matching lines @@
       // A new comment
       CollectCommentStatistics(isolate, it);
       // Skip code that was covered with previous comment
       prev_pc = it->rinfo()->pc();
     }
     it->next();
   }
   EnterComment(isolate, comment_txt, flat_delta);
 }
 
+// Collects code comment statistics
+static void CollectCodeCommentStatistics(HeapObject* obj, Isolate* isolate) {
+  // TODO(mythria): Also enable this for BytecodeArray when it supports
+  // RelocInformation.

[rmcilroy, 2016/05/23 10:16:30]

Bytecode arrays will never have RelocInfo, so this comment is incorrect.

[mythria, 2016/05/23 11:27:51]

Thanks. I removed the comment. Done.

+  if (!obj->IsCode()) {
+    return;
+  }
+  Code* code = Code::cast(obj);
+  RelocIterator it(code);
+  int delta = 0;
+  const byte* prev_pc = code->instruction_start();
+  while (!it.done()) {
+    if (it.rinfo()->rmode() == RelocInfo::COMMENT) {
+      delta += static_cast<int>(it.rinfo()->pc() - prev_pc);
+      CollectCommentStatistics(isolate, &it);
+      prev_pc = it.rinfo()->pc();
+    }
+    it.next();
+  }
 
-// Collects code size statistics:
-// - by code kind
-// - by code comment
-void PagedSpace::CollectCodeStatistics() {
-  Isolate* isolate = heap()->isolate();
-  HeapObjectIterator obj_it(this);
-  for (HeapObject* obj = obj_it.Next(); obj != NULL; obj = obj_it.Next()) {
-    if (obj->IsAbstractCode()) {
-      AbstractCode* code = AbstractCode::cast(obj);
-      isolate->code_kind_statistics()[code->kind()] += code->Size();
-    }
-    if (obj->IsCode()) {
-      // TODO(mythria): Also enable this for BytecodeArray when it supports
-      // RelocInformation.
-      Code* code = Code::cast(obj);
-      RelocIterator it(code);
-      int delta = 0;
-      const byte* prev_pc = code->instruction_start();
-      while (!it.done()) {
-        if (it.rinfo()->rmode() == RelocInfo::COMMENT) {
-          delta += static_cast<int>(it.rinfo()->pc() - prev_pc);
-          CollectCommentStatistics(isolate, &it);
-          prev_pc = it.rinfo()->pc();
-        }
-        it.next();
-      }
-
-      DCHECK(code->instruction_start() <= prev_pc &&
-             prev_pc <= code->instruction_end());
-      delta += static_cast<int>(code->instruction_end() - prev_pc);
-      EnterComment(isolate, "NoComment", delta);
-    }
-  }
+  DCHECK(code->instruction_start() <= prev_pc &&
+         prev_pc <= code->instruction_end());
+  delta += static_cast<int>(code->instruction_end() - prev_pc);
+  EnterComment(isolate, "NoComment", delta);
 }
 
 
 void PagedSpace::ReportStatistics() {
   int pct = static_cast<int>(Available() * 100 / Capacity());
   PrintF("  capacity: %" V8PRIdPTR ", waste: %" V8PRIdPTR
          ", available: %" V8PRIdPTR ", %%%d\n",
          Capacity(), Waste(), Available(), pct);
 
   if (heap()->mark_compact_collector()->sweeping_in_progress()) {
     heap()->mark_compact_collector()->EnsureSweepingCompleted();
   }
   ClearHistograms(heap()->isolate());
   HeapObjectIterator obj_it(this);
   for (HeapObject* obj = obj_it.Next(); obj != NULL; obj = obj_it.Next())
     CollectHistogramInfo(obj);
   ReportHistogram(heap()->isolate(), true);
 }
 #endif
 
+static void RecordMetadataStatistics(AbstractCode* abstract_code,

[rmcilroy, 2016/05/23 10:16:30]

This is code and metadata sizes isn't it? If so, update the function name.

[mythria, 2016/05/23 11:27:51]

Done.

+                                     Isolate* isolate) {
+  int size = abstract_code->InstructionAndMetadataSize();

[rmcilroy, 2016/05/23 10:16:30]

I don't like the name InstructionAndMetadataSize(). How about
SizeIncludingMetadata (also for both of the subclasses)?

[mythria, 2016/05/23 11:27:51]

 Done.

+  if (abstract_code->IsCode()) {
+    size += isolate->code_and_metadata_size();
+    isolate->set_code_and_metadata_size(size);
+  } else {
+    size += isolate->bytecode_and_metadata_size();
+    isolate->set_bytecode_and_metadata_size(size);
+  }
+}
+
+// Collects code size statistics:
+// - code and metadata size
+// - by code kind (only in debug mode)
+// - by code comment (only in debug mode)
+void PagedSpace::CollectCodeStatistics() {
+  Isolate* isolate = heap()->isolate();
+  HeapObjectIterator obj_it(this);
+  for (HeapObject* obj = obj_it.Next(); obj != NULL; obj = obj_it.Next()) {
+    if (obj->IsAbstractCode()) {
+      AbstractCode* code = AbstractCode::cast(obj);
+      RecordMetadataStatistics(code, isolate);
+#ifdef DEBUG
+      isolate->code_kind_statistics()[code->kind()] += code->Size();
+      CollectCodeCommentStatistics(obj, isolate);
+#endif
+    }
+  }
+}
+
+void PagedSpace::ResetCodeAndMetadataStatistics(Isolate* isolate) {
+  isolate->set_code_and_metadata_size(0);
+  isolate->set_bytecode_and_metadata_size(0);
+#ifdef DEBUG
+  ResetCodeStatistics(isolate);
+#endif
+}
 
 // -----------------------------------------------------------------------------
 // MapSpace implementation
 
 #ifdef VERIFY_HEAP
 void MapSpace::VerifyObject(HeapObject* object) { CHECK(object->IsMap()); }
 #endif
 
 
 // -----------------------------------------------------------------------------
@@ skipping 250 matching lines @@
           HeapObject* element_object = HeapObject::cast(element);
           CHECK(heap()->Contains(element_object));
           CHECK(element_object->map()->IsMap());
         }
       }
     }
   }
 }
 #endif
 
+void LargeObjectSpace::CollectCodeStatistics() {
+  Isolate* isolate = heap()->isolate();
+  LargeObjectIterator obj_it(this);
+  for (HeapObject* obj = obj_it.Next(); obj != NULL; obj = obj_it.Next()) {
+    if (obj->IsAbstractCode()) {
+      AbstractCode* code = AbstractCode::cast(obj);
+      RecordMetadataStatistics(code, isolate);
+#ifdef DEBUG
+      isolate->code_kind_statistics()[code->kind()] += code->Size();
+      CollectCodeCommentStatistics(obj, isolate);
+#endif
+    }
+  }
+}
 
 #ifdef DEBUG
 void LargeObjectSpace::Print() {
   OFStream os(stdout);
   LargeObjectIterator it(this);
   for (HeapObject* obj = it.Next(); obj != NULL; obj = it.Next()) {
     obj->Print(os);
   }
 }
 
 
 void LargeObjectSpace::ReportStatistics() {
   PrintF("  size: %" V8PRIdPTR "\n", size_);
   int num_objects = 0;
   ClearHistograms(heap()->isolate());
   LargeObjectIterator it(this);
   for (HeapObject* obj = it.Next(); obj != NULL; obj = it.Next()) {
     num_objects++;
     CollectHistogramInfo(obj);
   }
 
   PrintF(
       "  number of objects %d, "
       "size of objects %" V8PRIdPTR "\n",
       num_objects, objects_size_);
   if (num_objects > 0) ReportHistogram(heap()->isolate(), false);
 }
 
 
-void LargeObjectSpace::CollectCodeStatistics() {
-  Isolate* isolate = heap()->isolate();
-  LargeObjectIterator obj_it(this);
-  for (HeapObject* obj = obj_it.Next(); obj != NULL; obj = obj_it.Next()) {
-    if (obj->IsAbstractCode()) {
-      AbstractCode* code = AbstractCode::cast(obj);
-      isolate->code_kind_statistics()[code->kind()] += code->Size();
-    }
-  }
-}
-
-
 void Page::Print() {
   // Make a best-effort to print the objects in the page.
   PrintF("Page@%p in %s\n", this->address(),
          AllocationSpaceName(this->owner()->identity()));
   printf(" --------------------------------------\n");
   HeapObjectIterator objects(this);
   unsigned mark_size = 0;
   for (HeapObject* object = objects.Next(); object != NULL;
        object = objects.Next()) {
     bool is_marked = Marking::IsBlackOrGrey(Marking::MarkBitFrom(object));
     PrintF(" %c ", (is_marked ? '!' : ' '));  // Indent a little.
     if (is_marked) {
       mark_size += object->Size();
     }
     object->ShortPrint();
     PrintF("\n");
   }
   printf(" --------------------------------------\n");
   printf(" Marked: %x, LiveCount: %x\n", mark_size, LiveBytes());
 }
 
 #endif  // DEBUG
 }  // namespace internal
 }  // namespace v8