Adding V8 api to get memory statistics of spaces in V8::Heap.

src/heap/heap.cc

 // Copyright 2012 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/v8.h"
 
 #include "src/accessors.h"
 #include "src/api.h"
 #include "src/base/bits.h"
 #include "src/base/once.h"
@@ skipping 36 matching lines @@
 #include "src/mips/regexp-macro-assembler-mips.h"  // NOLINT
 #endif
 #if V8_TARGET_ARCH_MIPS64 && !V8_INTERPRETED_REGEXP
 #include "src/regexp-macro-assembler.h"
 #include "src/mips64/regexp-macro-assembler-mips64.h"
 #endif
 
 namespace v8 {
 namespace internal {
 
+namespace {
+const char* kNewSpaceName = "new_space";
+const char* kOldSpaceName = "old_space";
+const char* kCodeSpaceName = "code_space";
+const char* kMapSpaceName = "map_space";
+const char* kLoSpaceName = "large_object_space";
+}  // namespace
+
 
 Heap::Heap()
     : amount_of_external_allocated_memory_(0),
       amount_of_external_allocated_memory_at_last_global_gc_(0),
       isolate_(NULL),
       code_range_size_(0),
       // semispace_size_ should be a power of 2 and old_generation_size_ should
       // be a multiple of Page::kPageSize.
       reserved_semispace_size_(8 * (kPointerSize / 4) * MB),
       max_semi_space_size_(8 * (kPointerSize / 4) * MB),
@@ skipping 377 matching lines @@
 intptr_t Heap::SizeOfObjects() {
   intptr_t total = 0;
   AllSpaces spaces(this);
   for (Space* space = spaces.next(); space != NULL; space = spaces.next()) {
     total += space->SizeOfObjects();
   }
   return total;
 }
 
 
+const char* Heap::GetSpaceName(int idx) {
+  switch (idx) {
+    case NEW_SPACE:
+      return kNewSpaceName;
+    case OLD_SPACE:
+      return kOldSpaceName;
+    case MAP_SPACE:
+      return kMapSpaceName;
+    case CODE_SPACE:
+      return kCodeSpaceName;
+    case LO_SPACE:
+      return kLoSpaceName;

[rmcilroy, 2015/04/15 10:21:42]

add 'default' case with UNREACHABLE(); to ensure we always hit a valid index
(and remove the default nullptr return below) 

[ssid, 2015/04/15 10:43:58]

Added UNREACHABLE and keeping return null since compiler gives error if i dont
return at the end.

+  }
+  return nullptr;
+}
+
+
 void Heap::ClearAllICsByKind(Code::Kind kind) {
   HeapObjectIterator it(code_space());
 
   for (Object* object = it.Next(); object != NULL; object = it.Next()) {
     Code* code = Code::cast(object);
     Code::Kind current_kind = code->kind();
     if (current_kind == Code::FUNCTION ||
         current_kind == Code::OPTIMIZED_FUNCTION) {
       code->ClearInlineCaches(kind);
     }
@@ skipping 5837 matching lines @@
       static_cast<int>(object_sizes_last_time_[index]));
   CODE_AGE_LIST_COMPLETE(ADJUST_LAST_TIME_OBJECT_COUNT)
 #undef ADJUST_LAST_TIME_OBJECT_COUNT
 
   MemCopy(object_counts_last_time_, object_counts_, sizeof(object_counts_));
   MemCopy(object_sizes_last_time_, object_sizes_, sizeof(object_sizes_));
   ClearObjectStats();
 }
 }
 }  // namespace v8::internal