diff --git a/src/counters.h b/src/counters.h
index 6498a02..651cf54 100644
--- a/src/counters.h
+++ b/src/counters.h
@@ -1,35 +1,15 @@
-// Copyright 2007-2008 the V8 project authors. All rights reserved.
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-//       notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-//       copyright notice, this list of conditions and the following
-//       disclaimer in the documentation and/or other materials provided
-//       with the distribution.
-//     * Neither the name of Google Inc. nor the names of its
-//       contributors may be used to endorse or promote products derived
-//       from this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+// 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.
 
 #ifndef V8_COUNTERS_H_
 #define V8_COUNTERS_H_
 
-#include "../include/v8.h"
-#include "allocation.h"
+#include "include/v8.h"
+#include "src/allocation.h"
+#include "src/base/platform/elapsed-timer.h"
+#include "src/globals.h"
+#include "src/objects.h"
 
 namespace v8 {
 namespace internal {
@@ -113,14 +93,11 @@
 // The row has a 32bit value for each process/thread in the table and also
 // a name (stored in the table metadata).  Since the storage location can be
 // thread-specific, this class cannot be shared across threads.
-//
-// This class is designed to be POD initialized.  It will be registered with
-// the counter system on first use.  For example:
-//   StatsCounter c = { "c:myctr", NULL, false };
-struct StatsCounter {
-  const char* name_;
-  int* ptr_;
-  bool lookup_done_;
+class StatsCounter {
+ public:
+  StatsCounter() { }
+  explicit StatsCounter(Isolate* isolate, const char* name)
+      : isolate_(isolate), name_(name), ptr_(NULL), lookup_done_(false) { }
 
   // Sets the counter to a specific value.
   void Set(int value) {
@@ -162,15 +139,17 @@
   // given counter without calling the runtime system.
   int* GetInternalPointer() {
     int* loc = GetPtr();
-    ASSERT(loc != NULL);
+    DCHECK(loc != NULL);
     return loc;
   }
 
+  // Reset the cached internal pointer.
+  void Reset() { lookup_done_ = false; }
+
  protected:
   // Returns the cached address of this counter location.
   int* GetPtr() {
-    if (lookup_done_)
-      return ptr_;
+    if (lookup_done_) return ptr_;
     lookup_done_ = true;
     ptr_ = FindLocationInStatsTable();
     return ptr_;
@@ -178,46 +157,42 @@
 
  private:
   int* FindLocationInStatsTable() const;
-};
 
-// StatsCounterTimer t = { { L"t:foo", NULL, false }, 0, 0 };
-struct StatsCounterTimer {
-  StatsCounter counter_;
-
-  int64_t start_time_;
-  int64_t stop_time_;
-
-  // Start the timer.
-  void Start();
-
-  // Stop the timer and record the results.
-  void Stop();
-
-  // Returns true if the timer is running.
-  bool Running() {
-    return counter_.Enabled() && start_time_ != 0 && stop_time_ == 0;
-  }
-};
-
-// A HistogramTimer allows distributions of results to be created
-// HistogramTimer t = { L"foo", NULL, false, 0, 0 };
-struct HistogramTimer {
+  Isolate* isolate_;
   const char* name_;
-  void* histogram_;
+  int* ptr_;
   bool lookup_done_;
+};
 
-  int64_t start_time_;
-  int64_t stop_time_;
+// A Histogram represents a dynamically created histogram in the StatsTable.
+// It will be registered with the histogram system on first use.
+class Histogram {
+ public:
+  Histogram() { }
+  Histogram(const char* name,
+            int min,
+            int max,
+            int num_buckets,
+            Isolate* isolate)
+      : name_(name),
+        min_(min),
+        max_(max),
+        num_buckets_(num_buckets),
+        histogram_(NULL),
+        lookup_done_(false),
+        isolate_(isolate) { }
 
-  // Start the timer.
-  void Start();
+  // Add a single sample to this histogram.
+  void AddSample(int sample);
 
-  // Stop the timer and record the results.
-  void Stop();
+  // Returns true if this histogram is enabled.
+  bool Enabled() {
+    return GetHistogram() != NULL;
+  }
 
-  // Returns true if the timer is running.
-  bool Running() {
-    return (histogram_ != NULL) && (start_time_ != 0) && (stop_time_ == 0);
+  // Reset the cached internal pointer.
+  void Reset() {
+    lookup_done_ = false;
   }
 
  protected:
@@ -230,24 +205,506 @@
     return histogram_;
   }
 
+  const char* name() { return name_; }
+  Isolate* isolate() const { return isolate_; }
+
  private:
   void* CreateHistogram() const;
+
+  const char* name_;
+  int min_;
+  int max_;
+  int num_buckets_;
+  void* histogram_;
+  bool lookup_done_;
+  Isolate* isolate_;
+};
+
+// A HistogramTimer allows distributions of results to be created.
+class HistogramTimer : public Histogram {
+ public:
+  HistogramTimer() { }
+  HistogramTimer(const char* name,
+                 int min,
+                 int max,
+                 int num_buckets,
+                 Isolate* isolate)
+      : Histogram(name, min, max, num_buckets, isolate) {}
+
+  // Start the timer.
+  void Start();
+
+  // Stop the timer and record the results.
+  void Stop();
+
+  // Returns true if the timer is running.
+  bool Running() {
+    return Enabled() && timer_.IsStarted();
+  }
+
+  // TODO(bmeurer): Remove this when HistogramTimerScope is fixed.
+#ifdef DEBUG
+  base::ElapsedTimer* timer() { return &timer_; }
+#endif
+
+ private:
+  base::ElapsedTimer timer_;
 };
 
 // Helper class for scoping a HistogramTimer.
+// TODO(bmeurer): The ifdeffery is an ugly hack around the fact that the
+// Parser is currently reentrant (when it throws an error, we call back
+// into JavaScript and all bets are off), but ElapsedTimer is not
+// reentry-safe. Fix this properly and remove |allow_nesting|.
 class HistogramTimerScope BASE_EMBEDDED {
  public:
-  explicit HistogramTimerScope(HistogramTimer* timer) :
-  timer_(timer) {
+  explicit HistogramTimerScope(HistogramTimer* timer,
+                               bool allow_nesting = false)
+#ifdef DEBUG
+      : timer_(timer),
+        skipped_timer_start_(false) {
+    if (timer_->timer()->IsStarted() && allow_nesting) {
+      skipped_timer_start_ = true;
+    } else {
+      timer_->Start();
+    }
+  }
+#else
+      : timer_(timer) {
     timer_->Start();
   }
+#endif
   ~HistogramTimerScope() {
+#ifdef DEBUG
+    if (!skipped_timer_start_) {
+      timer_->Stop();
+    }
+#else
     timer_->Stop();
+#endif
   }
+
  private:
   HistogramTimer* timer_;
+#ifdef DEBUG
+  bool skipped_timer_start_;
+#endif
 };
 
+#define HISTOGRAM_RANGE_LIST(HR)                                              \
+  /* Generic range histograms */                                              \
+  HR(gc_idle_time_allotted_in_ms, V8.GCIdleTimeAllottedInMS, 0, 10000, 101)   \
+  HR(gc_idle_time_limit_overshot, V8.GCIdleTimeLimit.Overshot, 0, 10000, 101) \
+  HR(gc_idle_time_limit_undershot, V8.GCIdleTimeLimit.Undershot, 0, 10000, 101)
+
+#define HISTOGRAM_TIMER_LIST(HT)                             \
+  /* Garbage collection timers. */                           \
+  HT(gc_compactor, V8.GCCompactor)                           \
+  HT(gc_scavenger, V8.GCScavenger)                           \
+  HT(gc_context, V8.GCContext) /* GC context cleanup time */ \
+  HT(gc_idle_notification, V8.GCIdleNotification)            \
+  HT(gc_incremental_marking, V8.GCIncrementalMarking)        \
+  HT(gc_low_memory_notification, V8.GCLowMemoryNotification) \
+  /* Parsing timers. */                                      \
+  HT(parse, V8.Parse)                                        \
+  HT(parse_lazy, V8.ParseLazy)                               \
+  HT(pre_parse, V8.PreParse)                                 \
+  /* Total compilation times. */                             \
+  HT(compile, V8.Compile)                                    \
+  HT(compile_eval, V8.CompileEval)                           \
+  /* Serialization as part of compilation (code caching) */  \
+  HT(compile_serialize, V8.CompileSerialize)                 \
+  HT(compile_deserialize, V8.CompileDeserialize)
+
+
+#define HISTOGRAM_PERCENTAGE_LIST(HP)                                 \
+  /* Heap fragmentation. */                                           \
+  HP(external_fragmentation_total,                                    \
+     V8.MemoryExternalFragmentationTotal)                             \
+  HP(external_fragmentation_old_pointer_space,                        \
+     V8.MemoryExternalFragmentationOldPointerSpace)                   \
+  HP(external_fragmentation_old_data_space,                           \
+     V8.MemoryExternalFragmentationOldDataSpace)                      \
+  HP(external_fragmentation_code_space,                               \
+     V8.MemoryExternalFragmentationCodeSpace)                         \
+  HP(external_fragmentation_map_space,                                \
+     V8.MemoryExternalFragmentationMapSpace)                          \
+  HP(external_fragmentation_cell_space,                               \
+     V8.MemoryExternalFragmentationCellSpace)                         \
+  HP(external_fragmentation_property_cell_space,                      \
+     V8.MemoryExternalFragmentationPropertyCellSpace)                 \
+  HP(external_fragmentation_lo_space,                                 \
+     V8.MemoryExternalFragmentationLoSpace)                           \
+  /* Percentages of heap committed to each space. */                  \
+  HP(heap_fraction_new_space,                                         \
+     V8.MemoryHeapFractionNewSpace)                                   \
+  HP(heap_fraction_old_pointer_space,                                 \
+     V8.MemoryHeapFractionOldPointerSpace)                            \
+  HP(heap_fraction_old_data_space,                                    \
+     V8.MemoryHeapFractionOldDataSpace)                               \
+  HP(heap_fraction_code_space,                                        \
+     V8.MemoryHeapFractionCodeSpace)                                  \
+  HP(heap_fraction_map_space,                                         \
+     V8.MemoryHeapFractionMapSpace)                                   \
+  HP(heap_fraction_cell_space,                                        \
+     V8.MemoryHeapFractionCellSpace)                                  \
+  HP(heap_fraction_property_cell_space,                               \
+     V8.MemoryHeapFractionPropertyCellSpace)                          \
+  HP(heap_fraction_lo_space,                                          \
+     V8.MemoryHeapFractionLoSpace)                                    \
+  /* Percentage of crankshafted codegen. */                           \
+  HP(codegen_fraction_crankshaft,                                     \
+     V8.CodegenFractionCrankshaft)                                    \
+
+
+#define HISTOGRAM_MEMORY_LIST(HM)                                     \
+  HM(heap_sample_total_committed, V8.MemoryHeapSampleTotalCommitted)  \
+  HM(heap_sample_total_used, V8.MemoryHeapSampleTotalUsed)            \
+  HM(heap_sample_map_space_committed,                                 \
+     V8.MemoryHeapSampleMapSpaceCommitted)                            \
+  HM(heap_sample_cell_space_committed,                                \
+     V8.MemoryHeapSampleCellSpaceCommitted)                           \
+  HM(heap_sample_property_cell_space_committed,                       \
+     V8.MemoryHeapSamplePropertyCellSpaceCommitted)                   \
+  HM(heap_sample_code_space_committed,                                \
+     V8.MemoryHeapSampleCodeSpaceCommitted)                           \
+  HM(heap_sample_maximum_committed,                                   \
+     V8.MemoryHeapSampleMaximumCommitted)                             \
+
+
+// WARNING: STATS_COUNTER_LIST_* is a very large macro that is causing MSVC
+// Intellisense to crash.  It was broken into two macros (each of length 40
+// lines) rather than one macro (of length about 80 lines) to work around
+// this problem.  Please avoid using recursive macros of this length when
+// possible.
+#define STATS_COUNTER_LIST_1(SC)                                      \
+  /* Global Handle Count*/                                            \
+  SC(global_handles, V8.GlobalHandles)                                \
+  /* OS Memory allocated */                                           \
+  SC(memory_allocated, V8.OsMemoryAllocated)                          \
+  SC(normalized_maps, V8.NormalizedMaps)                              \
+  SC(props_to_dictionary, V8.ObjectPropertiesToDictionary)            \
+  SC(elements_to_dictionary, V8.ObjectElementsToDictionary)           \
+  SC(alive_after_last_gc, V8.AliveAfterLastGC)                        \
+  SC(objs_since_last_young, V8.ObjsSinceLastYoung)                    \
+  SC(objs_since_last_full, V8.ObjsSinceLastFull)                      \
+  SC(string_table_capacity, V8.StringTableCapacity)                   \
+  SC(number_of_symbols, V8.NumberOfSymbols)                           \
+  SC(script_wrappers, V8.ScriptWrappers)                              \
+  SC(call_initialize_stubs, V8.CallInitializeStubs)                   \
+  SC(call_premonomorphic_stubs, V8.CallPreMonomorphicStubs)           \
+  SC(call_normal_stubs, V8.CallNormalStubs)                           \
+  SC(call_megamorphic_stubs, V8.CallMegamorphicStubs)                 \
+  SC(inlined_copied_elements, V8.InlinedCopiedElements)              \
+  SC(arguments_adaptors, V8.ArgumentsAdaptors)                        \
+  SC(compilation_cache_hits, V8.CompilationCacheHits)                 \
+  SC(compilation_cache_misses, V8.CompilationCacheMisses)             \
+  SC(string_ctor_calls, V8.StringConstructorCalls)                    \
+  SC(string_ctor_conversions, V8.StringConstructorConversions)        \
+  SC(string_ctor_cached_number, V8.StringConstructorCachedNumber)     \
+  SC(string_ctor_string_value, V8.StringConstructorStringValue)       \
+  SC(string_ctor_gc_required, V8.StringConstructorGCRequired)         \
+  /* Amount of evaled source code. */                                 \
+  SC(total_eval_size, V8.TotalEvalSize)                               \
+  /* Amount of loaded source code. */                                 \
+  SC(total_load_size, V8.TotalLoadSize)                               \
+  /* Amount of parsed source code. */                                 \
+  SC(total_parse_size, V8.TotalParseSize)                             \
+  /* Amount of source code skipped over using preparsing. */          \
+  SC(total_preparse_skipped, V8.TotalPreparseSkipped)                 \
+  /* Number of symbol lookups skipped using preparsing */             \
+  SC(total_preparse_symbols_skipped, V8.TotalPreparseSymbolSkipped)   \
+  /* Amount of compiled source code. */                               \
+  SC(total_compile_size, V8.TotalCompileSize)                         \
+  /* Amount of source code compiled with the full codegen. */         \
+  SC(total_full_codegen_source_size, V8.TotalFullCodegenSourceSize)   \
+  /* Number of contexts created from scratch. */                      \
+  SC(contexts_created_from_scratch, V8.ContextsCreatedFromScratch)    \
+  /* Number of contexts created by partial snapshot. */               \
+  SC(contexts_created_by_snapshot, V8.ContextsCreatedBySnapshot)      \
+  /* Number of code objects found from pc. */                         \
+  SC(pc_to_code, V8.PcToCode)                                         \
+  SC(pc_to_code_cached, V8.PcToCodeCached)                            \
+  /* The store-buffer implementation of the write barrier. */         \
+  SC(store_buffer_compactions, V8.StoreBufferCompactions)             \
+  SC(store_buffer_overflows, V8.StoreBufferOverflows)
+
+
+#define STATS_COUNTER_LIST_2(SC)                                               \
+  /* Number of code stubs. */                                                  \
+  SC(code_stubs, V8.CodeStubs)                                                 \
+  /* Amount of stub code. */                                                   \
+  SC(total_stubs_code_size, V8.TotalStubsCodeSize)                             \
+  /* Amount of (JS) compiled code. */                                          \
+  SC(total_compiled_code_size, V8.TotalCompiledCodeSize)                       \
+  SC(gc_compactor_caused_by_request, V8.GCCompactorCausedByRequest)            \
+  SC(gc_compactor_caused_by_promoted_data, V8.GCCompactorCausedByPromotedData) \
+  SC(gc_compactor_caused_by_oldspace_exhaustion,                               \
+     V8.GCCompactorCausedByOldspaceExhaustion)                                 \
+  SC(gc_last_resort_from_js, V8.GCLastResortFromJS)                            \
+  SC(gc_last_resort_from_handles, V8.GCLastResortFromHandles)                  \
+  /* How is the generic keyed-load stub used? */                               \
+  SC(keyed_load_generic_smi, V8.KeyedLoadGenericSmi)                           \
+  SC(keyed_load_generic_symbol, V8.KeyedLoadGenericSymbol)                     \
+  SC(keyed_load_generic_lookup_cache, V8.KeyedLoadGenericLookupCache)          \
+  SC(keyed_load_generic_slow, V8.KeyedLoadGenericSlow)                         \
+  SC(keyed_load_polymorphic_stubs, V8.KeyedLoadPolymorphicStubs)               \
+  SC(keyed_load_external_array_slow, V8.KeyedLoadExternalArraySlow)            \
+  /* How is the generic keyed-call stub used? */                               \
+  SC(keyed_call_generic_smi_fast, V8.KeyedCallGenericSmiFast)                  \
+  SC(keyed_call_generic_smi_dict, V8.KeyedCallGenericSmiDict)                  \
+  SC(keyed_call_generic_lookup_cache, V8.KeyedCallGenericLookupCache)          \
+  SC(keyed_call_generic_lookup_dict, V8.KeyedCallGenericLookupDict)            \
+  SC(keyed_call_generic_slow, V8.KeyedCallGenericSlow)                         \
+  SC(keyed_call_generic_slow_load, V8.KeyedCallGenericSlowLoad)                \
+  SC(named_load_global_stub, V8.NamedLoadGlobalStub)                           \
+  SC(named_store_global_inline, V8.NamedStoreGlobalInline)                     \
+  SC(named_store_global_inline_miss, V8.NamedStoreGlobalInlineMiss)            \
+  SC(keyed_store_polymorphic_stubs, V8.KeyedStorePolymorphicStubs)             \
+  SC(keyed_store_external_array_slow, V8.KeyedStoreExternalArraySlow)          \
+  SC(store_normal_miss, V8.StoreNormalMiss)                                    \
+  SC(store_normal_hit, V8.StoreNormalHit)                                      \
+  SC(cow_arrays_created_stub, V8.COWArraysCreatedStub)                         \
+  SC(cow_arrays_created_runtime, V8.COWArraysCreatedRuntime)                   \
+  SC(cow_arrays_converted, V8.COWArraysConverted)                              \
+  SC(call_miss, V8.CallMiss)                                                   \
+  SC(keyed_call_miss, V8.KeyedCallMiss)                                        \
+  SC(load_miss, V8.LoadMiss)                                                   \
+  SC(keyed_load_miss, V8.KeyedLoadMiss)                                        \
+  SC(call_const, V8.CallConst)                                                 \
+  SC(call_const_fast_api, V8.CallConstFastApi)                                 \
+  SC(call_const_interceptor, V8.CallConstInterceptor)                          \
+  SC(call_const_interceptor_fast_api, V8.CallConstInterceptorFastApi)          \
+  SC(call_global_inline, V8.CallGlobalInline)                                  \
+  SC(call_global_inline_miss, V8.CallGlobalInlineMiss)                         \
+  SC(constructed_objects, V8.ConstructedObjects)                               \
+  SC(constructed_objects_runtime, V8.ConstructedObjectsRuntime)                \
+  SC(negative_lookups, V8.NegativeLookups)                                     \
+  SC(negative_lookups_miss, V8.NegativeLookupsMiss)                            \
+  SC(megamorphic_stub_cache_probes, V8.MegamorphicStubCacheProbes)             \
+  SC(megamorphic_stub_cache_misses, V8.MegamorphicStubCacheMisses)             \
+  SC(megamorphic_stub_cache_updates, V8.MegamorphicStubCacheUpdates)           \
+  SC(array_function_runtime, V8.ArrayFunctionRuntime)                          \
+  SC(array_function_native, V8.ArrayFunctionNative)                            \
+  SC(for_in, V8.ForIn)                                                         \
+  SC(enum_cache_hits, V8.EnumCacheHits)                                        \
+  SC(enum_cache_misses, V8.EnumCacheMisses)                                    \
+  SC(zone_segment_bytes, V8.ZoneSegmentBytes)                                  \
+  SC(fast_new_closure_total, V8.FastNewClosureTotal)                           \
+  SC(fast_new_closure_try_optimized, V8.FastNewClosureTryOptimized)            \
+  SC(fast_new_closure_install_optimized, V8.FastNewClosureInstallOptimized)    \
+  SC(string_add_runtime, V8.StringAddRuntime)                                  \
+  SC(string_add_native, V8.StringAddNative)                                    \
+  SC(string_add_runtime_ext_to_one_byte, V8.StringAddRuntimeExtToOneByte)      \
+  SC(sub_string_runtime, V8.SubStringRuntime)                                  \
+  SC(sub_string_native, V8.SubStringNative)                                    \
+  SC(string_add_make_two_char, V8.StringAddMakeTwoChar)                        \
+  SC(string_compare_native, V8.StringCompareNative)                            \
+  SC(string_compare_runtime, V8.StringCompareRuntime)                          \
+  SC(regexp_entry_runtime, V8.RegExpEntryRuntime)                              \
+  SC(regexp_entry_native, V8.RegExpEntryNative)                                \
+  SC(number_to_string_native, V8.NumberToStringNative)                         \
+  SC(number_to_string_runtime, V8.NumberToStringRuntime)                       \
+  SC(math_acos, V8.MathAcos)                                                   \
+  SC(math_asin, V8.MathAsin)                                                   \
+  SC(math_atan, V8.MathAtan)                                                   \
+  SC(math_atan2, V8.MathAtan2)                                                 \
+  SC(math_exp, V8.MathExp)                                                     \
+  SC(math_floor, V8.MathFloor)                                                 \
+  SC(math_log, V8.MathLog)                                                     \
+  SC(math_pow, V8.MathPow)                                                     \
+  SC(math_round, V8.MathRound)                                                 \
+  SC(math_sqrt, V8.MathSqrt)                                                   \
+  SC(stack_interrupts, V8.StackInterrupts)                                     \
+  SC(runtime_profiler_ticks, V8.RuntimeProfilerTicks)                          \
+  SC(bounds_checks_eliminated, V8.BoundsChecksEliminated)                      \
+  SC(bounds_checks_hoisted, V8.BoundsChecksHoisted)                            \
+  SC(soft_deopts_requested, V8.SoftDeoptsRequested)                            \
+  SC(soft_deopts_inserted, V8.SoftDeoptsInserted)                              \
+  SC(soft_deopts_executed, V8.SoftDeoptsExecuted)                              \
+  /* Number of write barriers in generated code. */                            \
+  SC(write_barriers_dynamic, V8.WriteBarriersDynamic)                          \
+  SC(write_barriers_static, V8.WriteBarriersStatic)                            \
+  SC(new_space_bytes_available, V8.MemoryNewSpaceBytesAvailable)               \
+  SC(new_space_bytes_committed, V8.MemoryNewSpaceBytesCommitted)               \
+  SC(new_space_bytes_used, V8.MemoryNewSpaceBytesUsed)                         \
+  SC(old_pointer_space_bytes_available,                                        \
+     V8.MemoryOldPointerSpaceBytesAvailable)                                   \
+  SC(old_pointer_space_bytes_committed,                                        \
+     V8.MemoryOldPointerSpaceBytesCommitted)                                   \
+  SC(old_pointer_space_bytes_used, V8.MemoryOldPointerSpaceBytesUsed)          \
+  SC(old_data_space_bytes_available, V8.MemoryOldDataSpaceBytesAvailable)      \
+  SC(old_data_space_bytes_committed, V8.MemoryOldDataSpaceBytesCommitted)      \
+  SC(old_data_space_bytes_used, V8.MemoryOldDataSpaceBytesUsed)                \
+  SC(code_space_bytes_available, V8.MemoryCodeSpaceBytesAvailable)             \
+  SC(code_space_bytes_committed, V8.MemoryCodeSpaceBytesCommitted)             \
+  SC(code_space_bytes_used, V8.MemoryCodeSpaceBytesUsed)                       \
+  SC(map_space_bytes_available, V8.MemoryMapSpaceBytesAvailable)               \
+  SC(map_space_bytes_committed, V8.MemoryMapSpaceBytesCommitted)               \
+  SC(map_space_bytes_used, V8.MemoryMapSpaceBytesUsed)                         \
+  SC(cell_space_bytes_available, V8.MemoryCellSpaceBytesAvailable)             \
+  SC(cell_space_bytes_committed, V8.MemoryCellSpaceBytesCommitted)             \
+  SC(cell_space_bytes_used, V8.MemoryCellSpaceBytesUsed)                       \
+  SC(property_cell_space_bytes_available,                                      \
+     V8.MemoryPropertyCellSpaceBytesAvailable)                                 \
+  SC(property_cell_space_bytes_committed,                                      \
+     V8.MemoryPropertyCellSpaceBytesCommitted)                                 \
+  SC(property_cell_space_bytes_used, V8.MemoryPropertyCellSpaceBytesUsed)      \
+  SC(lo_space_bytes_available, V8.MemoryLoSpaceBytesAvailable)                 \
+  SC(lo_space_bytes_committed, V8.MemoryLoSpaceBytesCommitted)                 \
+  SC(lo_space_bytes_used, V8.MemoryLoSpaceBytesUsed)
+
+
+// This file contains all the v8 counters that are in use.
+class Counters {
+ public:
+#define HR(name, caption, min, max, num_buckets) \
+  Histogram* name() { return &name##_; }
+  HISTOGRAM_RANGE_LIST(HR)
+#undef HR
+
+#define HT(name, caption) \
+  HistogramTimer* name() { return &name##_; }
+  HISTOGRAM_TIMER_LIST(HT)
+#undef HT
+
+#define HP(name, caption) \
+  Histogram* name() { return &name##_; }
+  HISTOGRAM_PERCENTAGE_LIST(HP)
+#undef HP
+
+#define HM(name, caption) \
+  Histogram* name() { return &name##_; }
+  HISTOGRAM_MEMORY_LIST(HM)
+#undef HM
+
+#define SC(name, caption) \
+  StatsCounter* name() { return &name##_; }
+  STATS_COUNTER_LIST_1(SC)
+  STATS_COUNTER_LIST_2(SC)
+#undef SC
+
+#define SC(name) \
+  StatsCounter* count_of_##name() { return &count_of_##name##_; } \
+  StatsCounter* size_of_##name() { return &size_of_##name##_; }
+  INSTANCE_TYPE_LIST(SC)
+#undef SC
+
+#define SC(name) \
+  StatsCounter* count_of_CODE_TYPE_##name() \
+    { return &count_of_CODE_TYPE_##name##_; } \
+  StatsCounter* size_of_CODE_TYPE_##name() \
+    { return &size_of_CODE_TYPE_##name##_; }
+  CODE_KIND_LIST(SC)
+#undef SC
+
+#define SC(name) \
+  StatsCounter* count_of_FIXED_ARRAY_##name() \
+    { return &count_of_FIXED_ARRAY_##name##_; } \
+  StatsCounter* size_of_FIXED_ARRAY_##name() \
+    { return &size_of_FIXED_ARRAY_##name##_; }
+  FIXED_ARRAY_SUB_INSTANCE_TYPE_LIST(SC)
+#undef SC
+
+#define SC(name) \
+  StatsCounter* count_of_CODE_AGE_##name() \
+    { return &count_of_CODE_AGE_##name##_; } \
+  StatsCounter* size_of_CODE_AGE_##name() \
+    { return &size_of_CODE_AGE_##name##_; }
+  CODE_AGE_LIST_COMPLETE(SC)
+#undef SC
+
+  enum Id {
+#define RATE_ID(name, caption) k_##name,
+    HISTOGRAM_TIMER_LIST(RATE_ID)
+#undef RATE_ID
+#define PERCENTAGE_ID(name, caption) k_##name,
+    HISTOGRAM_PERCENTAGE_LIST(PERCENTAGE_ID)
+#undef PERCENTAGE_ID
+#define MEMORY_ID(name, caption) k_##name,
+    HISTOGRAM_MEMORY_LIST(MEMORY_ID)
+#undef MEMORY_ID
+#define COUNTER_ID(name, caption) k_##name,
+    STATS_COUNTER_LIST_1(COUNTER_ID)
+    STATS_COUNTER_LIST_2(COUNTER_ID)
+#undef COUNTER_ID
+#define COUNTER_ID(name) kCountOf##name, kSizeOf##name,
+    INSTANCE_TYPE_LIST(COUNTER_ID)
+#undef COUNTER_ID
+#define COUNTER_ID(name) kCountOfCODE_TYPE_##name, \
+    kSizeOfCODE_TYPE_##name,
+    CODE_KIND_LIST(COUNTER_ID)
+#undef COUNTER_ID
+#define COUNTER_ID(name) kCountOfFIXED_ARRAY__##name, \
+    kSizeOfFIXED_ARRAY__##name,
+    FIXED_ARRAY_SUB_INSTANCE_TYPE_LIST(COUNTER_ID)
+#undef COUNTER_ID
+#define COUNTER_ID(name) kCountOfCODE_AGE__##name, \
+    kSizeOfCODE_AGE__##name,
+    CODE_AGE_LIST_COMPLETE(COUNTER_ID)
+#undef COUNTER_ID
+    stats_counter_count
+  };
+
+  void ResetCounters();
+  void ResetHistograms();
+
+ private:
+#define HR(name, caption, min, max, num_buckets) Histogram name##_;
+  HISTOGRAM_RANGE_LIST(HR)
+#undef HR
+
+#define HT(name, caption) \
+  HistogramTimer name##_;
+  HISTOGRAM_TIMER_LIST(HT)
+#undef HT
+
+#define HP(name, caption) \
+  Histogram name##_;
+  HISTOGRAM_PERCENTAGE_LIST(HP)
+#undef HP
+
+#define HM(name, caption) \
+  Histogram name##_;
+  HISTOGRAM_MEMORY_LIST(HM)
+#undef HM
+
+#define SC(name, caption) \
+  StatsCounter name##_;
+  STATS_COUNTER_LIST_1(SC)
+  STATS_COUNTER_LIST_2(SC)
+#undef SC
+
+#define SC(name) \
+  StatsCounter size_of_##name##_; \
+  StatsCounter count_of_##name##_;
+  INSTANCE_TYPE_LIST(SC)
+#undef SC
+
+#define SC(name) \
+  StatsCounter size_of_CODE_TYPE_##name##_; \
+  StatsCounter count_of_CODE_TYPE_##name##_;
+  CODE_KIND_LIST(SC)
+#undef SC
+
+#define SC(name) \
+  StatsCounter size_of_FIXED_ARRAY_##name##_; \
+  StatsCounter count_of_FIXED_ARRAY_##name##_;
+  FIXED_ARRAY_SUB_INSTANCE_TYPE_LIST(SC)
+#undef SC
+
+#define SC(name) \
+  StatsCounter size_of_CODE_AGE_##name##_; \
+  StatsCounter count_of_CODE_AGE_##name##_;
+  CODE_AGE_LIST_COMPLETE(SC)
+#undef SC
+
+  friend class Isolate;
+
+  explicit Counters(Isolate* isolate);
+
+  DISALLOW_IMPLICIT_CONSTRUCTORS(Counters);
+};
 
 } }  // namespace v8::internal