Make CPU profile models public and refactor model building code

runtime/vm/profiler_service.cc

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/profiler_service.h"
 
 #include "vm/growable_array.h"
 #include "vm/native_symbol.h"
 #include "vm/object.h"
 #include "vm/os.h"
 #include "vm/profiler.h"
 #include "vm/reusable_handles.h"
 #include "vm/scope_timer.h"
 
 namespace dart {
 
 DECLARE_FLAG(int, profile_depth);
 DECLARE_FLAG(int, profile_period);
 
 DEFINE_FLAG(bool, trace_profiler, false, "Trace profiler.");
 
-// Forward declarations.
-class CodeRegion;
-class ProfileFunction;
-class ProfileFunctionTable;
-
-
 class DeoptimizedCodeSet : public ZoneAllocated {
  public:
   explicit DeoptimizedCodeSet(Isolate* isolate)
       : previous_(
             GrowableObjectArray::ZoneHandle(isolate->deoptimized_code_array())),
         current_(GrowableObjectArray::ZoneHandle(
             previous_.IsNull() ? GrowableObjectArray::null() :
                                  GrowableObjectArray::New())) {
   }
 
@@ skipping 47 matching lines @@
     }
     return size;
   }
 
   // Array holding code that is being kept around only for the profiler.
   const GrowableObjectArray& previous_;
   // Array holding code that should continue to be kept around for the profiler.
   const GrowableObjectArray& current_;
 };
 
-class ProfileFunction : public ZoneAllocated {
- public:
-  enum Kind {
-    kDartFunction,    // Dart function.
-    kNativeFunction,  // Synthetic function for Native (C/C++).
-    kTagFunction,     // Synthetic function for a VM or User tag.
-    kStubFunction,    // Synthetic function for stub code.
-    kUnkownFunction,  // A singleton function for unknown objects.
-  };
-  ProfileFunction(Kind kind,
+
+ProfileFunction::ProfileFunction(Kind kind,
                   const char* name,
                   const Function& function,
                   const intptr_t table_index)
-      : kind_(kind),
-        name_(name),
-        function_(Function::ZoneHandle(function.raw())),
-        table_index_(table_index),
-        code_objects_(new ZoneGrowableArray<intptr_t>()),
-        exclusive_ticks_(0),
-        inclusive_ticks_(0),
-        inclusive_tick_serial_(0) {
-    ASSERT((kind_ != kDartFunction) || !function_.IsNull());
-    ASSERT((kind_ != kDartFunction) || (table_index_ >= 0));
-    ASSERT(code_objects_->length() == 0);
-  }
-
-  const char* name() const {
-    ASSERT(name_ != NULL);
-    return name_;
-  }
-
-  RawFunction* function() const {
-    return function_.raw();
-  }
-
-  intptr_t index() const {
-    return table_index_;
-  }
-
-  Kind kind() const {
-    return kind_;
-  }
-
-  const char* KindToCString(Kind kind) {
-    switch (kind) {
-      case kDartFunction:
-        return "Dart";
-      case kNativeFunction:
-        return "Native";
-      case kTagFunction:
-        return "Tag";
-      case kStubFunction:
-        return "Stub";
-      case kUnkownFunction:
-        return "Collected";
-      default:
-        UNIMPLEMENTED();
-        return "";
-    }
-  }
-
-  void Dump() {
-    const char* n = (name_ == NULL) ? "<NULL>" : name_;
-    const char* fn = "";
-    if (!function_.IsNull()) {
-      fn = function_.ToQualifiedCString();
-    }
-    OS::Print("%s %s [%s]", KindToCString(kind()), n, fn);
-  }
-
-  void AddCodeObjectIndex(intptr_t index) {
-    for (intptr_t i = 0; i < code_objects_->length(); i++) {
-      if ((*code_objects_)[i] == index) {
-        return;
-      }
-    }
-    code_objects_->Add(index);
-  }
-
-  intptr_t inclusive_ticks() const {
-    return inclusive_ticks_;
-  }
-  void inc_inclusive_ticks() {
+    : kind_(kind),
+      name_(name),
+      function_(Function::ZoneHandle(function.raw())),
+      table_index_(table_index),
+      profile_codes_(0),
+      exclusive_ticks_(0),
+      inclusive_ticks_(0) {
+  ASSERT((kind_ != kDartFunction) || !function_.IsNull());
+  ASSERT((kind_ != kDartFunction) || (table_index_ >= 0));
+  ASSERT(profile_codes_.length() == 0);
+}
+
+
+void ProfileFunction::Tick(bool exclusive, intptr_t inclusive_serial) {
+  if (exclusive) {
+    exclusive_ticks_++;
+  } else {
+    if (inclusive_serial_ == inclusive_serial) {
+      // Already ticket.
+      return;
+    }
+    inclusive_serial_ = inclusive_serial;
     inclusive_ticks_++;
   }
-  intptr_t exclusive_ticks() const {
-    return exclusive_ticks_;
-  }
-
-  void Tick(bool exclusive, intptr_t serial) {
-    // Assert that exclusive ticks are never passed a valid serial number.
-    ASSERT((exclusive && (serial == -1)) || (!exclusive && (serial != -1)));
-    if (!exclusive && (inclusive_tick_serial_ == serial)) {
-      // We've already given this object an inclusive tick for this sample.
+}
+
+
+const char* ProfileFunction::KindToCString(Kind kind) {
+  switch (kind) {
+    case kDartFunction:
+      return "Dart";
+    case kNativeFunction:
+      return "Native";
+    case kTagFunction:
+      return "Tag";
+    case kStubFunction:
+      return "Stub";
+    case kUnknownFunction:
+      return "Collected";
+    default:
+      UNIMPLEMENTED();
+      return "";
+  }
+}
+
+
+void ProfileFunction::PrintToJSONObject(JSONObject* func) {
+  func->AddProperty("type", "@Function");
+  func->AddProperty("name", name());
+  func->AddProperty("_kind", KindToCString(kind()));
+}
+
+
+void ProfileFunction::PrintToJSONArray(JSONArray* functions) {
+  JSONObject obj(functions);
+  obj.AddProperty("kind", KindToCString(kind()));
+  obj.AddPropertyF("inclusiveTicks", "%" Pd "", inclusive_ticks());
+  obj.AddPropertyF("exclusiveTicks", "%" Pd "", exclusive_ticks());
+  if (kind() == kDartFunction) {
+    ASSERT(!function_.IsNull());
+    obj.AddProperty("function", function_);
+  } else {
+    JSONObject func(&obj, "function");
+    PrintToJSONObject(&func);
+  }
+  {
+    JSONArray codes(&obj, "codes");
+    for (intptr_t i = 0; i < profile_codes_.length(); i++) {
+      intptr_t code_index = profile_codes_[i];
+      codes.AddValue(code_index);
+    }
+  }
+}
+
+
+void ProfileFunction::AddProfileCode(intptr_t code_table_index) {
+  for (intptr_t i = 0; i < profile_codes_.length(); i++) {
+    if (profile_codes_[i] == code_table_index) {
       return;
     }
-    if (exclusive) {
-      exclusive_ticks_++;
-    } else {
-      inclusive_ticks_++;
-      // Mark the last serial we ticked the inclusive count.
-      inclusive_tick_serial_ = serial;
-    }
-  }
-
-  void PrintToJSONObject(JSONObject* func) {
-    func->AddProperty("type", "@Function");
-    func->AddProperty("name", name());
-    func->AddProperty("_kind", KindToCString(kind()));
-  }
-
-  void PrintToJSONArray(JSONArray* functions) {
-    JSONObject obj(functions);
-    obj.AddProperty("kind", KindToCString(kind()));
-    obj.AddPropertyF("inclusiveTicks", "%" Pd "", inclusive_ticks());
-    obj.AddPropertyF("exclusiveTicks", "%" Pd "", exclusive_ticks());
-    if (kind() == kDartFunction) {
-      ASSERT(!function_.IsNull());
-      obj.AddProperty("function", function_);
-    } else {
-      JSONObject func(&obj, "function");
-      PrintToJSONObject(&func);
-    }
-    {
-      JSONArray codes(&obj, "codes");
-      for (intptr_t i = 0; i < code_objects_->length(); i++) {
-        intptr_t code_index = (*code_objects_)[i];
-        codes.AddValue(code_index);
-      }
-    }
-  }
-
- private:
-  const Kind kind_;
-  const char* name_;
-  const Function& function_;
-  const intptr_t table_index_;
-  ZoneGrowableArray<intptr_t>* code_objects_;
-  intptr_t exclusive_ticks_;
-  intptr_t inclusive_ticks_;
-  intptr_t inclusive_tick_serial_;
-};
-
-
-class ProfileFunctionTable : public ValueObject {
+  }
+  profile_codes_.Add(code_table_index);
+}
+
+
+ProfileCodeAddress::ProfileCodeAddress(uword pc)
+    : pc_(pc),
+      exclusive_ticks_(0),
+      inclusive_ticks_(0) {
+}
+
+
+void ProfileCodeAddress::Tick(bool exclusive) {
+  if (exclusive) {
+    exclusive_ticks_++;
+  } else {
+    inclusive_ticks_++;
+  }
+}
+
+
+ProfileCode::ProfileCode(Kind kind,
+                         uword start,
+                         uword end,
+                         int64_t timestamp,
+                         const Code& code)
+    : kind_(kind),
+      start_(start),
+      end_(end),
+      exclusive_ticks_(0),
+      inclusive_ticks_(0),
+      inclusive_serial_(-1),
+      code_(code),
+      name_(NULL),
+      compile_timestamp_(0),
+      function_(NULL),
+      code_table_index_(-1),
+      address_ticks_(0) {
+}
+
+
+void ProfileCode::AdjustExtent(uword start, uword end) {
+  if (start < start_) {
+    start_ = start;
+  }
+  if (end > end_) {
+    end_ = end;
+  }
+  ASSERT(start_ < end_);
+}
+
+
+bool ProfileCode::Overlaps(const ProfileCode* other) const {
+  ASSERT(other != NULL);
+  return other->Contains(start_)   ||
+         other->Contains(end_ - 1) ||
+         Contains(other->start())  ||
+         Contains(other->end() - 1);
+}
+
+
+bool ProfileCode::IsOptimizedDart() const {
+  return !code_.IsNull() && code_.is_optimized();
+}
+
+
+void ProfileCode::SetName(const char* name) {
+  if (name == NULL) {
+    name_ = NULL;
+  }
+  intptr_t len = strlen(name);
+  name_ = Isolate::Current()->current_zone()->Alloc<const char>(len + 1);
+  strncpy(const_cast<char*>(name_), name, len);
+  const_cast<char*>(name_)[len] = '\0';
+}
+
+
+void ProfileCode::GenerateAndSetSymbolName(const char* prefix) {
+  const intptr_t kBuffSize = 512;
+  char buff[kBuffSize];
+  OS::SNPrint(&buff[0], kBuffSize-1, "%s [%" Px ", %" Px ")",
+              prefix, start(), end());
+  SetName(buff);
+}
+
+
+void ProfileCode::Tick(uword pc, bool exclusive, intptr_t serial) {
+  if (exclusive) {
+    exclusive_ticks_++;
+  } else {
+    if (inclusive_serial_ == serial) {
+      // Already ticked for this sample.
+      return;
+    }
+    inclusive_serial_ = serial;
+    inclusive_ticks_++;
+  }
+  TickAddress(pc, exclusive);
+}
+
+
+void ProfileCode::TickAddress(uword pc, bool exclusive) {
+  const intptr_t length = address_ticks_.length();
+
+  intptr_t i = 0;
+  for (; i < length; i++) {
+    ProfileCodeAddress& entry = address_ticks_[i];
+    if (entry.pc() == pc) {
+      // Tick the address entry.
+      entry.Tick(exclusive);
+      return;
+    }
+    if (entry.pc() > pc) {
+      break;
+    }
+  }
+
+  // New address, add entry.
+  ProfileCodeAddress entry(pc);
+
+  entry.Tick(exclusive);
+
+  if (i < length) {
+    // Insert at i.
+    address_ticks_.InsertAt(i, entry);
+  } else {
+    // Add to end.
+    address_ticks_.Add(entry);
+  }
+}
+
+
+void ProfileCode::PrintNativeCode(JSONObject* profile_code_obj) {
+  ASSERT(kind() == kNativeCode);
+  JSONObject obj(profile_code_obj, "code");
+  obj.AddProperty("type", "@Code");
+  obj.AddProperty("kind", "Native");
+  obj.AddProperty("name", name());
+  obj.AddProperty("_optimized", false);
+  obj.AddPropertyF("start", "%" Px "", start());
+  obj.AddPropertyF("end", "%" Px "", end());
+  {
+    // Generate a fake function entry.
+    JSONObject func(&obj, "function");
+    ASSERT(function_ != NULL);
+    function_->PrintToJSONObject(&func);
+  }
+}
+
+
+void ProfileCode::PrintCollectedCode(JSONObject* profile_code_obj) {
+  ASSERT(kind() == kCollectedCode);
+  JSONObject obj(profile_code_obj, "code");
+  obj.AddProperty("type", "@Code");
+  obj.AddProperty("kind", "Collected");
+  obj.AddProperty("name", name());
+  obj.AddProperty("_optimized", false);
+  obj.AddPropertyF("start", "%" Px "", start());
+  obj.AddPropertyF("end", "%" Px "", end());
+  {
+    // Generate a fake function entry.
+    JSONObject func(&obj, "function");
+    ASSERT(function_ != NULL);
+    function_->PrintToJSONObject(&func);
+  }
+}
+
+
+void ProfileCode::PrintOverwrittenCode(JSONObject* profile_code_obj) {
+  ASSERT(kind() == kReusedCode);
+  JSONObject obj(profile_code_obj, "code");
+  obj.AddProperty("type", "@Code");
+  obj.AddProperty("kind", "Collected");
+  obj.AddProperty("name", name());
+  obj.AddProperty("_optimized", false);
+  obj.AddPropertyF("start", "%" Px "", start());
+  obj.AddPropertyF("end", "%" Px "", end());
+  {
+    // Generate a fake function entry.
+    JSONObject func(&obj, "function");
+    ASSERT(function_ != NULL);
+    function_->PrintToJSONObject(&func);
+  }
+}
+
+
+void ProfileCode::PrintTagCode(JSONObject* profile_code_obj) {
+  ASSERT(kind() == kTagCode);
+  JSONObject obj(profile_code_obj, "code");
+  obj.AddProperty("type", "@Code");
+  obj.AddProperty("kind", "Tag");
+  obj.AddProperty("name", name());
+  obj.AddPropertyF("start", "%" Px "", start());
+  obj.AddPropertyF("end", "%" Px "", end());
+  obj.AddProperty("_optimized", false);
+  {
+    // Generate a fake function entry.
+    JSONObject func(&obj, "function");
+    ASSERT(function_ != NULL);
+    function_->PrintToJSONObject(&func);
+  }
+}
+
+
+const char* ProfileCode::KindToCString(Kind kind) {
+  switch (kind) {
+    case kDartCode:
+      return "Dart";
+    case kCollectedCode:
+      return "Collected";
+    case kNativeCode:
+      return "Native";
+    case kReusedCode:
+      return "Overwritten";
+    case kTagCode:
+      return "Tag";
+  }
+  UNREACHABLE();
+  return NULL;
+}
+
+
+void ProfileCode::PrintToJSONArray(JSONArray* codes) {
+  JSONObject obj(codes);
+  obj.AddProperty("kind", ProfileCode::KindToCString(kind()));
+  obj.AddPropertyF("inclusiveTicks", "%" Pd "", inclusive_ticks());
+  obj.AddPropertyF("exclusiveTicks", "%" Pd "", exclusive_ticks());
+  if (kind() == kDartCode) {
+    ASSERT(!code_.IsNull());
+    obj.AddProperty("code", code_);
+  } else if (kind() == kCollectedCode) {
+    PrintCollectedCode(&obj);
+  } else if (kind() == kReusedCode) {
+    PrintOverwrittenCode(&obj);
+  } else if (kind() == kTagCode) {
+    PrintTagCode(&obj);
+  } else {
+    ASSERT(kind() == kNativeCode);
+    PrintNativeCode(&obj);
+  }
+  {
+    JSONArray ticks(&obj, "ticks");
+    for (intptr_t i = 0; i < address_ticks_.length(); i++) {
+      const ProfileCodeAddress& entry = address_ticks_[i];
+      ticks.AddValueF("%" Px "", entry.pc());
+      ticks.AddValueF("%" Pd "", entry.exclusive_ticks());
+      ticks.AddValueF("%" Pd "", entry.inclusive_ticks());
+    }
+  }
+}
+
+
+class ProfileFunctionTable : public ZoneAllocated {
  public:
   ProfileFunctionTable()
       : null_function_(Function::ZoneHandle()),
-        table_(new ZoneGrowableArray<ProfileFunction*>()),
+        table_(8),
         unknown_function_(NULL) {
+    unknown_function_ = Add(ProfileFunction::kUnknownFunction,
+                            "<unknown Dart function>");
   }
 
   ProfileFunction* LookupOrAdd(const Function& function) {
     ASSERT(!function.IsNull());
     ProfileFunction* profile_function = Lookup(function);
     if (profile_function != NULL) {
       return profile_function;
     }
     return Add(function);
   }
 
   intptr_t LookupIndex(const Function& function) {
     ASSERT(!function.IsNull());
-    for (intptr_t i = 0; i < table_->length(); i++) {
-      ProfileFunction* profile_function = (*table_)[i];
+    for (intptr_t i = 0; i < table_.length(); i++) {
+      ProfileFunction* profile_function = table_[i];
       if (profile_function->function() == function.raw()) {
         return i;
       }
     }
     return -1;
   }
 
   ProfileFunction* GetUnknown() {
-    if (unknown_function_ == NULL) {
-      // Construct.
-      unknown_function_ = Add(ProfileFunction::kUnkownFunction,
-                              "<unknown Dart function>");
-    }
     ASSERT(unknown_function_ != NULL);
     return unknown_function_;
   }
 
   // No protection against being called more than once for the same tag_id.
   ProfileFunction* AddTag(uword tag_id, const char* name) {
     // TODO(johnmccutchan): Canonicalize ProfileFunctions for tags.
     return Add(ProfileFunction::kTagFunction, name);
   }
 
   // No protection against being called more than once for the same native
   // address.
   ProfileFunction* AddNative(uword start_address, const char* name) {
     // TODO(johnmccutchan): Canonicalize ProfileFunctions for natives.
     return Add(ProfileFunction::kNativeFunction, name);
   }
 
   // No protection against being called more tha once for the same stub.
   ProfileFunction* AddStub(uword start_address, const char* name) {
     return Add(ProfileFunction::kStubFunction, name);
   }
 
-  intptr_t Length() const {
-    return table_->length();
+  intptr_t length() const {
+    return table_.length();
   }
 
   ProfileFunction* At(intptr_t i) const {
     ASSERT(i >= 0);
-    ASSERT(i < Length());
-    return (*table_)[i];
+    ASSERT(i < length());
+    return table_[i];
   }
 
  private:
   ProfileFunction* Add(ProfileFunction::Kind kind, const char* name) {
     ASSERT(kind != ProfileFunction::kDartFunction);
     ASSERT(name != NULL);
     ProfileFunction* profile_function =
         new ProfileFunction(kind,
                             name,
                             null_function_,
-                            table_->length());
-    table_->Add(profile_function);
+                            table_.length());
+    table_.Add(profile_function);
     return profile_function;
   }
 
   ProfileFunction* Add(const Function& function) {
     ASSERT(Lookup(function) == NULL);
     ProfileFunction* profile_function =
         new ProfileFunction(ProfileFunction::kDartFunction,
                             NULL,
                             function,
-                            table_->length());
-    table_->Add(profile_function);
+                            table_.length());
+    table_.Add(profile_function);
     return profile_function;
   }
 
   ProfileFunction* Lookup(const Function& function) {
     ASSERT(!function.IsNull());
     intptr_t index = LookupIndex(function);
     if (index == -1) {
       return NULL;
     }
-    return (*table_)[index];
+    return table_[index];
   }
 
   const Function& null_function_;
-  ZoneGrowableArray<ProfileFunction*>* table_;
-
+  ZoneGrowableArray<ProfileFunction*> table_;
   ProfileFunction* unknown_function_;
 };
 
 
-struct AddressEntry {
-  uword pc;
-  intptr_t exclusive_ticks;
-  intptr_t inclusive_ticks;
+ProfileFunction* ProfileCode::SetFunctionAndName(ProfileFunctionTable* table) {
+  ASSERT(function_ == NULL);
 
-  void tick(bool exclusive) {
-    if (exclusive) {
-      exclusive_ticks++;
+  ProfileFunction* function = NULL;
+  if ((kind() == kReusedCode) || (kind() == kCollectedCode)) {
+    if (name() == NULL) {
+      // Lazily set generated name.
+      GenerateAndSetSymbolName("[Collected]");
+    }
+    // Map these to a canonical unknown function.
+    function = table->GetUnknown();
+  } else if (kind() == kDartCode) {
+    ASSERT(!code_.IsNull());
+    const Object& obj = Object::Handle(code_.owner());
+    if (obj.IsFunction()) {
+      const String& user_name = String::Handle(code_.PrettyName());
+      function = table->LookupOrAdd(Function::Cast(obj));
+      SetName(user_name.ToCString());
     } else {
-      inclusive_ticks++;
+      // A stub.
+      const String& user_name = String::Handle(code_.PrettyName());
+      function = table->AddStub(start(), user_name.ToCString());
+      SetName(user_name.ToCString());
     }
+  } else if (kind() == kNativeCode) {
+    if (name() == NULL) {
+      // Lazily set generated name.
+      GenerateAndSetSymbolName("[Native]");
+    }
+    function = table->AddNative(start(), name());
+  } else if (kind() == kTagCode) {
+    if (name() == NULL) {
+      if (UserTags::IsUserTag(start())) {
+        const char* tag_name = UserTags::TagName(start());
+        ASSERT(tag_name != NULL);
+        SetName(tag_name);
+      } else if (VMTag::IsVMTag(start()) ||
+                 VMTag::IsRuntimeEntryTag(start()) ||
+                 VMTag::IsNativeEntryTag(start())) {
+        const char* tag_name = VMTag::TagName(start());
+        ASSERT(tag_name != NULL);
+        SetName(tag_name);
+      } else {
+        if (start() == VMTag::kRootTagId) {
+          SetName("Root");
+        } else {
+          ASSERT(start() == VMTag::kTruncatedTagId);
+          SetName("[Truncated]");
+        }
+      }
+    }
+    function = table->AddTag(start(), name());
+  } else {
+    UNREACHABLE();
   }
-};
+  ASSERT(function != NULL);
 
-typedef bool (*RegionCompare)(uword pc, uword region_start, uword region_end);
+  function->AddProfileCode(code_table_index());
 
-// A contiguous address region that holds code. Each CodeRegion has a "kind"
-// which describes the type of code contained inside the region. Each
-// region covers the following interval: [start, end).
-class CodeRegion : public ZoneAllocated {
+  function_ = function;
+  return function_;
+}
+
+
+typedef bool (*RangeCompare)(uword pc, uword region_start, uword region_end);
+
+class ProfileCodeTable : public ZoneAllocated {
  public:
-  enum Kind {
-    kDartCode,       // Live Dart code.
-    kCollectedCode,  // Dead Dart code.
-    kNativeCode,     // Native code.
-    kReusedCode,     // Dead Dart code that has been reused by new kDartCode.
-    kTagCode,        // A special kind of code representing a tag.
-  };
-
-  CodeRegion(Kind kind,
-             uword start,
-             uword end,
-             int64_t timestamp,
-             const Code& code)
-      : kind_(kind),
-        start_(start),
-        end_(end),
-        inclusive_ticks_(0),
-        exclusive_ticks_(0),
-        inclusive_tick_serial_(0),
-        name_(NULL),
-        compile_timestamp_(timestamp),
-        code_(Code::ZoneHandle(code.raw())),
-        profile_function_(NULL),
-        code_table_index_(-1) {
-    ASSERT(start_ < end_);
-    // Ensure all kDartCode have a valid code_ object.
-    ASSERT((kind != kDartCode) || (!code_.IsNull()));
+  ProfileCodeTable()
+      : table_(8) {
   }
 
-  uword start() const { return start_; }
-  void set_start(uword start) {
-    start_ = start;
+  intptr_t length() const { return table_.length(); }
+
+  ProfileCode* At(intptr_t index) const {
+    ASSERT(index >= 0);
+    ASSERT(index < length());
+    return table_[index];
   }
 
-  uword end() const { return end_; }
-  void set_end(uword end) {
-    end_ = end;
-  }
-
-  void AdjustExtent(uword start, uword end) {
-    if (start < start_) {
-      start_ = start;
-    }
-    if (end > end_) {
-      end_ = end;
-    }
-    ASSERT(start_ < end_);
-  }
-
-  bool contains(uword pc) const {
-    return (pc >= start_) && (pc < end_);
-  }
-
-  bool overlaps(const CodeRegion* other) const {
-    ASSERT(other != NULL);
-    return other->contains(start_)   ||
-           other->contains(end_ - 1) ||
-           contains(other->start())  ||
-           contains(other->end() - 1);
-  }
-
-  int64_t compile_timestamp() const { return compile_timestamp_; }
-  void set_compile_timestamp(int64_t timestamp) {
-    compile_timestamp_ = timestamp;
-  }
-
-  intptr_t inclusive_ticks() const { return inclusive_ticks_; }
-  void set_inclusive_ticks(intptr_t inclusive_ticks) {
-    inclusive_ticks_ = inclusive_ticks;
-  }
-  void inc_inclusive_ticks() {
-    inclusive_ticks_++;
-  }
-
-  intptr_t exclusive_ticks() const { return exclusive_ticks_; }
-  void set_exclusive_ticks(intptr_t exclusive_ticks) {
-    exclusive_ticks_ = exclusive_ticks;
-  }
-
-  const char* name() const { return name_; }
-  void SetName(const char* name) {
-    if (name == NULL) {
-      name_ = NULL;
-    }
-    intptr_t len = strlen(name);
-    name_ = Isolate::Current()->current_zone()->Alloc<const char>(len + 1);
-    strncpy(const_cast<char*>(name_), name, len);
-    const_cast<char*>(name_)[len] = '\0';
-  }
-
-  bool IsOptimizedDart() const {
-    return !code_.IsNull() && code_.is_optimized();
-  }
-
-  RawCode* code() const {
-    return code_.raw();
-  }
-
-  ProfileFunction* SetFunctionAndName(ProfileFunctionTable* table) {
-    ASSERT(profile_function_ == NULL);
-
-    ProfileFunction* function = NULL;
-    if ((kind() == kReusedCode) || (kind() == kCollectedCode)) {
-      if (name() == NULL) {
-        // Lazily set generated name.
-        GenerateAndSetSymbolName("[Collected]");
-      }
-      // Map these to a canonical unknown function.
-      function = table->GetUnknown();
-    } else if (kind() == kDartCode) {
-      ASSERT(!code_.IsNull());
-      const Object& obj = Object::Handle(code_.owner());
-      if (obj.IsFunction()) {
-        const String& user_name = String::Handle(code_.PrettyName());
-        function = table->LookupOrAdd(Function::Cast(obj));
-        SetName(user_name.ToCString());
-      } else {
-        // A stub.
-        const String& user_name = String::Handle(code_.PrettyName());
-        function = table->AddStub(start(), user_name.ToCString());
-        SetName(user_name.ToCString());
-      }
-    } else if (kind() == kNativeCode) {
-      if (name() == NULL) {
-        // Lazily set generated name.
-        GenerateAndSetSymbolName("[Native]");
-      }
-      function = table->AddNative(start(), name());
-    } else if (kind() == kTagCode) {
-      if (name() == NULL) {
-        if (UserTags::IsUserTag(start())) {
-          const char* tag_name = UserTags::TagName(start());
-          ASSERT(tag_name != NULL);
-          SetName(tag_name);
-        } else if (VMTag::IsVMTag(start()) ||
-                   VMTag::IsRuntimeEntryTag(start()) ||
-                   VMTag::IsNativeEntryTag(start())) {
-          const char* tag_name = VMTag::TagName(start());
-          ASSERT(tag_name != NULL);
-          SetName(tag_name);
-        } else {
-          if (start() == VMTag::kRootTagId) {
-            SetName("Root");
-          } else {
-            ASSERT(start() == VMTag::kTruncatedTagId);
-            SetName("[Truncated]");
-          }
-        }
-      }
-      function = table->AddTag(start(), name());
-    } else {
-      UNREACHABLE();
-    }
-    ASSERT(function != NULL);
-    // Register this CodeRegion with this function.
-    function->AddCodeObjectIndex(code_table_index());
-    profile_function_ = function;
-    return profile_function_;
-  }
-
-  ProfileFunction* function() const {
-    ASSERT(profile_function_ != NULL);
-    return profile_function_;
-  }
-
-  void set_code_table_index(intptr_t code_table_index) {
-    ASSERT(code_table_index_ == -1);
-    ASSERT(code_table_index != -1);
-    code_table_index_ = code_table_index;
-  }
-  intptr_t code_table_index() const {
-    ASSERT(code_table_index_ != -1);
-    return code_table_index_;
-  }
-
-  Kind kind() const { return kind_; }
-
-  static const char* KindToCString(Kind kind) {
-    switch (kind) {
-      case kDartCode:
-        return "Dart";
-      case kCollectedCode:
-        return "Collected";
-      case kNativeCode:
-        return "Native";
-      case kReusedCode:
-        return "Overwritten";
-      case kTagCode:
-        return "Tag";
-    }
-    UNREACHABLE();
-    return NULL;
-  }
-
-  void DebugPrint() const {
-    OS::Print("%s [%" Px ", %" Px ") %" Pd64 "\n",
-              KindToCString(kind_),
-              start(),
-              end(),
-              compile_timestamp_);
-  }
-
-  void Tick(uword pc, bool exclusive, intptr_t serial) {
-    // Assert that exclusive ticks are never passed a valid serial number.
-    ASSERT((exclusive && (serial == -1)) || (!exclusive && (serial != -1)));
-    if (!exclusive && (inclusive_tick_serial_ == serial)) {
-      // We've already given this code object an inclusive tick for this sample.
-      return;
-    }
-    // Tick the code object.
-    if (exclusive) {
-      exclusive_ticks_++;
-    } else {
-      inclusive_ticks_++;
-      // Mark the last serial we ticked the inclusive count.
-      inclusive_tick_serial_ = serial;
-    }
-    TickAddress(pc, exclusive);
-  }
-
-  void PrintNativeCode(JSONObject* profile_code_obj) {
-    ASSERT(kind() == kNativeCode);
-    JSONObject obj(profile_code_obj, "code");
-    obj.AddProperty("type", "@Code");
-    obj.AddProperty("kind", "Native");
-    obj.AddProperty("name", name());
-    obj.AddProperty("_optimized", false);
-    obj.AddPropertyF("start", "%" Px "", start());
-    obj.AddPropertyF("end", "%" Px "", end());
-    {
-      // Generate a fake function entry.
-      JSONObject func(&obj, "function");
-      profile_function_->PrintToJSONObject(&func);
-    }
-  }
-
-  void PrintCollectedCode(JSONObject* profile_code_obj) {
-    ASSERT(kind() == kCollectedCode);
-    JSONObject obj(profile_code_obj, "code");
-    obj.AddProperty("type", "@Code");
-    obj.AddProperty("kind", "Collected");
-    obj.AddProperty("name", name());
-    obj.AddProperty("_optimized", false);
-    obj.AddPropertyF("start", "%" Px "", start());
-    obj.AddPropertyF("end", "%" Px "", end());
-    {
-      // Generate a fake function entry.
-      JSONObject func(&obj, "function");
-      profile_function_->PrintToJSONObject(&func);
-    }
-  }
-
-  void PrintOverwrittenCode(JSONObject* profile_code_obj) {
-    ASSERT(kind() == kReusedCode);
-    JSONObject obj(profile_code_obj, "code");
-    obj.AddProperty("type", "@Code");
-    obj.AddProperty("kind", "Collected");
-    obj.AddProperty("name", name());
-    obj.AddProperty("_optimized", false);
-    obj.AddPropertyF("start", "%" Px "", start());
-    obj.AddPropertyF("end", "%" Px "", end());
-    {
-      // Generate a fake function entry.
-      JSONObject func(&obj, "function");
-      ASSERT(profile_function_ != NULL);
-      profile_function_->PrintToJSONObject(&func);
-    }
-  }
-
-  void PrintTagCode(JSONObject* profile_code_obj) {
-    ASSERT(kind() == kTagCode);
-    JSONObject obj(profile_code_obj, "code");
-    obj.AddProperty("type", "@Code");
-    obj.AddProperty("kind", "Tag");
-    obj.AddProperty("name", name());
-    obj.AddPropertyF("start", "%" Px "", start());
-    obj.AddPropertyF("end", "%" Px "", end());
-    obj.AddProperty("_optimized", false);
-    {
-      // Generate a fake function entry.
-      JSONObject func(&obj, "function");
-      ASSERT(profile_function_ != NULL);
-      profile_function_->PrintToJSONObject(&func);
-    }
-  }
-
-  void PrintToJSONArray(JSONArray* codes) {
-    JSONObject obj(codes);
-    obj.AddProperty("kind", KindToCString(kind()));
-    obj.AddPropertyF("inclusiveTicks", "%" Pd "", inclusive_ticks());
-    obj.AddPropertyF("exclusiveTicks", "%" Pd "", exclusive_ticks());
-    if (kind() == kDartCode) {
-      ASSERT(!code_.IsNull());
-      obj.AddProperty("code", code_);
-    } else if (kind() == kCollectedCode) {
-      PrintCollectedCode(&obj);
-    } else if (kind() == kReusedCode) {
-      PrintOverwrittenCode(&obj);
-    } else if (kind() == kTagCode) {
-      PrintTagCode(&obj);
-    } else {
-      ASSERT(kind() == kNativeCode);
-      PrintNativeCode(&obj);
-    }
-    {
-      JSONArray ticks(&obj, "ticks");
-      for (intptr_t i = 0; i < address_table_.length(); i++) {
-        const AddressEntry& entry = address_table_[i];
-        ticks.AddValueF("%" Px "", entry.pc);
-        ticks.AddValueF("%" Pd "", entry.exclusive_ticks);
-        ticks.AddValueF("%" Pd "", entry.inclusive_ticks);
-      }
-    }
-  }
-
- private:
-  void TickAddress(uword pc, bool exclusive) {
-    const intptr_t length = address_table_.length();
-    intptr_t i = 0;
-    for (; i < length; i++) {
-      AddressEntry& entry = address_table_[i];
-      if (entry.pc == pc) {
-        // Tick the address entry.
-        entry.tick(exclusive);
-        return;
-      }
-      if (entry.pc > pc) {
-        break;
-      }
-    }
-    // New address, add entry.
-    AddressEntry entry;
-    entry.pc = pc;
-    entry.exclusive_ticks = 0;
-    entry.inclusive_ticks = 0;
-    entry.tick(exclusive);
-    if (i < length) {
-      // Insert at i.
-      address_table_.InsertAt(i, entry);
-    } else {
-      // Add to end.
-      address_table_.Add(entry);
-    }
-  }
-
-  void GenerateAndSetSymbolName(const char* prefix) {
-    const intptr_t kBuffSize = 512;
-    char buff[kBuffSize];
-    OS::SNPrint(&buff[0], kBuffSize-1, "%s [%" Px ", %" Px ")",
-                prefix, start(), end());
-    SetName(buff);
-  }
-
-  // CodeRegion kind.
-  const Kind kind_;
-  // CodeRegion start address.
-  uword start_;
-  // CodeRegion end address.
-  uword end_;
-  // Inclusive ticks.
-  intptr_t inclusive_ticks_;
-  // Exclusive ticks.
-  intptr_t exclusive_ticks_;
-  // Inclusive tick serial number, ensures that each CodeRegion is only given
-  // a single inclusive tick per sample.
-  intptr_t inclusive_tick_serial_;
-  // Name of code region.
-  const char* name_;
-  // The compilation timestamp associated with this code region.
-  int64_t compile_timestamp_;
-  // Dart code object (may be null).
-  const Code& code_;
-  // Pointer to ProfileFunction.
-  ProfileFunction* profile_function_;
-  // Final code table index.
-  intptr_t code_table_index_;
-  ZoneGrowableArray<AddressEntry> address_table_;
-  DISALLOW_COPY_AND_ASSIGN(CodeRegion);
-};
-
-
-// A sorted table of CodeRegions. Does not allow for overlap.
-class CodeRegionTable : public ValueObject {
- public:
-  enum TickResult {
-    kTicked = 0,     // CodeRegion found and ticked.
-    kNotFound = -1,   // No CodeRegion found.
-    kNewerCode = -2,  // CodeRegion found but it was compiled after sample.
-  };
-
-  CodeRegionTable() :
-      code_region_table_(new ZoneGrowableArray<CodeRegion*>(64)) {
-  }
-
-  // Ticks the CodeRegion containing pc if it is alive at timestamp.
-  TickResult Tick(uword pc,
-                  bool exclusive,
-                  intptr_t serial,
-                  int64_t timestamp) {
-    intptr_t index = FindIndex(pc);
-    if (index < 0) {
-      // Not found.
-      return kNotFound;
-    }
-    ASSERT(index < code_region_table_->length());
-    CodeRegion* region = At(index);
-    if (region->compile_timestamp() > timestamp) {
-      // Compiled after tick.
-      return kNewerCode;
-    }
-    region->Tick(pc, exclusive, serial);
-    return kTicked;
-  }
-
-  // Table length.
-  intptr_t Length() const { return code_region_table_->length(); }
-
-  // Get the CodeRegion at index.
-  CodeRegion* At(intptr_t index) const {
-    return (*code_region_table_)[index];
-  }
-
-  // Find the table index to the CodeRegion containing pc.
+  // Find the table index to the ProfileCode containing pc.
   // Returns < 0 if not found.
-  intptr_t FindIndex(uword pc) const {
-    intptr_t index = FindRegionIndex(pc, &CompareLowerBound);
-    const CodeRegion* code_region = NULL;
-    if (index == code_region_table_->length()) {
+  intptr_t FindCodeIndexForPC(uword pc) const {
+    intptr_t index = FindCodeIndex(pc, &CompareLowerBound);
+    if (index == length()) {
       // Not present.
       return -1;
     }
-    code_region = At(index);
-    if (code_region->contains(pc)) {
-      // Found at index.
-      return index;
+    const ProfileCode* code = At(index);
+    if (!code->Contains(pc)) {
+      // Not present.
+      return -1;
     }
-    return -2;
+    // Found at index.
+    return index;
   }
 
-  // Insert code_region into the table. Returns the table index where the
-  // CodeRegion was inserted. Will merge with an overlapping CodeRegion if
-  // one is present.
-  intptr_t InsertCodeRegion(CodeRegion* code_region) {
-    const uword start = code_region->start();
-    const uword end = code_region->end();
-    const intptr_t length = code_region_table_->length();
+  ProfileCode* FindCodeForPC(uword pc) const {
+    intptr_t index = FindCodeIndexForPC(pc);
+    if (index < 0) {
+      return NULL;
+    }
+    return At(index);
+  }
+
+  // Insert |new_code| into the table. Returns the table index where |new_code|
+  // was inserted. Will merge with an overlapping ProfileCode if one is present.
+  intptr_t InsertCode(ProfileCode* new_code) {
+    const uword start = new_code->start();
+    const uword end = new_code->end();
+    const intptr_t length = table_.length();
     if (length == 0) {
-      code_region_table_->Add(code_region);
+      table_.Add(new_code);
       return length;
     }
-    // Determine the correct place to insert or merge code_region into table.
-    intptr_t lo = FindRegionIndex(start, &CompareLowerBound);
-    intptr_t hi = FindRegionIndex(end - 1, &CompareUpperBound);
+    // Determine the correct place to insert or merge |new_code| into table.
+    intptr_t lo = FindCodeIndex(start, &CompareLowerBound);
+    intptr_t hi = FindCodeIndex(end - 1, &CompareUpperBound);
     // TODO(johnmccutchan): Simplify below logic.
     if ((lo == length) && (hi == length)) {
       lo = length - 1;
     }
     if (lo == length) {
-      CodeRegion* region = At(hi);
-      if (region->overlaps(code_region)) {
-        HandleOverlap(region, code_region, start, end);
+      ProfileCode* code = At(hi);
+      if (code->Overlaps(new_code)) {
+        HandleOverlap(code, new_code, start, end);
         return hi;
       }
-      code_region_table_->Add(code_region);
+      table_.Add(new_code);
       return length;
     } else if (hi == length) {
-      CodeRegion* region = At(lo);
-      if (region->overlaps(code_region)) {
-        HandleOverlap(region, code_region, start, end);
+      ProfileCode* code = At(lo);
+      if (code->Overlaps(new_code)) {
+        HandleOverlap(code, new_code, start, end);
         return lo;
       }
-      code_region_table_->Add(code_region);
+      table_.Add(new_code);
       return length;
     } else if (lo == hi) {
-      CodeRegion* region = At(lo);
-      if (region->overlaps(code_region)) {
-        HandleOverlap(region, code_region, start, end);
+      ProfileCode* code = At(lo);
+      if (code->Overlaps(new_code)) {
+        HandleOverlap(code, new_code, start, end);
         return lo;
       }
-      code_region_table_->InsertAt(lo, code_region);
+      table_.InsertAt(lo, new_code);
       return lo;
     } else {
-      CodeRegion* region = At(lo);
-      if (region->overlaps(code_region)) {
-        HandleOverlap(region, code_region, start, end);
+      ProfileCode* code = At(lo);
+      if (code->Overlaps(new_code)) {
+        HandleOverlap(code, new_code, start, end);
         return lo;
       }
-      region = At(hi);
-      if (region->overlaps(code_region)) {
-        HandleOverlap(region, code_region, start, end);
+      code = At(hi);
+      if (code->Overlaps(new_code)) {
+        HandleOverlap(code, new_code, start, end);
         return hi;
       }
-      code_region_table_->InsertAt(hi, code_region);
+      table_.InsertAt(hi, new_code);
       return hi;
     }
     UNREACHABLE();
   }
 
-  void Verify() {
-    VerifyOrder();
-    VerifyOverlap();
-  }
-
-  void DebugPrint() {
-    OS::Print("Dumping CodeRegionTable:\n");
-    for (intptr_t i = 0; i < code_region_table_->length(); i++) {
-      CodeRegion* region = At(i);
-      region->DebugPrint();
-    }
-  }
-
  private:
-  intptr_t FindRegionIndex(uword pc, RegionCompare comparator) const {
+  intptr_t FindCodeIndex(uword pc, RangeCompare comparator) const {
     ASSERT(comparator != NULL);
-    intptr_t count = code_region_table_->length();
+    intptr_t count = table_.length();
     intptr_t first = 0;
     while (count > 0) {
       intptr_t it = first;
       intptr_t step = count / 2;
       it += step;
-      const CodeRegion* code_region = At(it);
-      if (comparator(pc, code_region->start(), code_region->end())) {
+      const ProfileCode* code = At(it);
+      if (comparator(pc, code->start(), code->end())) {
         first = ++it;
         count -= (step + 1);
       } else {
         count = step;
       }
     }
     return first;
   }
 
   static bool CompareUpperBound(uword pc, uword start, uword end) {
     return pc >= end;
   }
 
   static bool CompareLowerBound(uword pc, uword start, uword end) {
     return end <= pc;
   }
 
-  void HandleOverlap(CodeRegion* region, CodeRegion* code_region,
+  void HandleOverlap(ProfileCode* existing, ProfileCode* code,
                      uword start, uword end) {
     // We should never see overlapping Dart code regions.
-    ASSERT(region->kind() != CodeRegion::kDartCode);
+    ASSERT(existing->kind() != ProfileCode::kDartCode);
     // We should never see overlapping Tag code regions.
-    ASSERT(region->kind() != CodeRegion::kTagCode);
+    ASSERT(existing->kind() != ProfileCode::kTagCode);
     // When code regions overlap, they should be of the same kind.
-    ASSERT(region->kind() == code_region->kind());
-    region->AdjustExtent(start, end);
+    ASSERT(existing->kind() == code->kind());
+    existing->AdjustExtent(start, end);
   }
 
   void VerifyOrder() {
-    const intptr_t length = code_region_table_->length();
+    const intptr_t length = table_.length();
     if (length == 0) {
       return;
     }
-    uword last = (*code_region_table_)[0]->end();
+    uword last = table_[0]->end();
     for (intptr_t i = 1; i < length; i++) {
-      CodeRegion* a = (*code_region_table_)[i];
+      ProfileCode* a = table_[i];
       ASSERT(last <= a->start());
       last = a->end();
     }
   }
 
   void VerifyOverlap() {
-    const intptr_t length = code_region_table_->length();
+    const intptr_t length = table_.length();
     for (intptr_t i = 0; i < length; i++) {
-      CodeRegion* a = (*code_region_table_)[i];
+      ProfileCode* a = table_[i];
       for (intptr_t j = i+1; j < length; j++) {
-        CodeRegion* b = (*code_region_table_)[j];
-        ASSERT(!a->contains(b->start()) &&
-               !a->contains(b->end() - 1) &&
-               !b->contains(a->start()) &&
-               !b->contains(a->end() - 1));
+        ProfileCode* b = table_[j];
+        ASSERT(!a->Contains(b->start()) &&
+               !a->Contains(b->end() - 1) &&
+               !b->Contains(a->start()) &&
+               !b->Contains(a->end() - 1));
       }
     }
   }
 
-  ZoneGrowableArray<CodeRegion*>* code_region_table_;
+  ZoneGrowableArray<ProfileCode*> table_;
 };
 
 
-class CodeRegionTableBuilder {
+ProfileTrieNode::ProfileTrieNode(intptr_t table_index)
+    : table_index_(table_index),
+      count_(0),
+      children_(0) {
+  ASSERT(table_index_ >= 0);
+}
+
+
+ProfileTrieNode::~ProfileTrieNode() {
+}
+
+
+void ProfileTrieNode::SortChildren() {
+  children_.Sort(ProfileTrieNodeCompare);
+  // Recurse.
+  for (intptr_t i = 0; i < children_.length(); i++) {
+    children_[i]->SortChildren();
+  }
+}
+
+
+class ProfileCodeTrieNode : public ProfileTrieNode {
  public:
-  CodeRegionTableBuilder(Isolate* isolate,
-                         CodeRegionTable* live_code_table,
-                         CodeRegionTable* dead_code_table,
-                         CodeRegionTable* tag_code_table,
-                         DeoptimizedCodeSet* deoptimized_code)
-      : live_code_table_(live_code_table),
-        dead_code_table_(dead_code_table),
-        tag_code_table_(tag_code_table),
-        isolate_(isolate),
-        vm_isolate_(Dart::vm_isolate()),
-        null_code_(Code::ZoneHandle()),
-        deoptimized_code_(deoptimized_code) {
-    ASSERT(live_code_table_ != NULL);
-    ASSERT(dead_code_table_ != NULL);
-    ASSERT(tag_code_table_ != NULL);
-    ASSERT(isolate_ != NULL);
-    ASSERT(vm_isolate_ != NULL);
-    ASSERT(null_code_.IsNull());
-    frames_ = 0;
-    min_time_ = kMaxInt64;
-    max_time_ = 0;
+  explicit ProfileCodeTrieNode(intptr_t table_index)
+      : ProfileTrieNode(table_index) {
   }
 
-  void Build(ProcessedSampleBuffer* buffer) {
-    for (intptr_t i = 0; i < buffer->length(); i++) {
-      ProcessedSample* sample = buffer->At(i);
-      VisitSample(i, sample);
+  void PrintToJSONArray(JSONArray* array) const {
+    ASSERT(array != NULL);
+    // Write CodeRegion index.
+    array->AddValue(table_index());
+    // Write count.
+    array->AddValue(count());
+    // Write number of children.
+    intptr_t child_count = NumChildren();
+    array->AddValue(child_count);
+    // Recurse.
+    for (intptr_t i = 0; i < child_count; i++) {
+      children_[i]->PrintToJSONArray(array);
     }
   }
 
-  intptr_t frames() const { return frames_; }
-
-  intptr_t  TimeDeltaMicros() const {
-    return static_cast<intptr_t>(max_time_ - min_time_);
+  ProfileCodeTrieNode* GetChild(intptr_t child_table_index) {
+    const intptr_t length = NumChildren();
+    intptr_t i = 0;
+    while (i < length) {
+      ProfileCodeTrieNode* child =
+          reinterpret_cast<ProfileCodeTrieNode*>(children_[i]);
+      if (child->table_index() == child_table_index) {
+        return child;
+      }
+      if (child->table_index() > child_table_index) {
+        break;
+      }
+      i++;
+    }
+    ProfileCodeTrieNode* child = new ProfileCodeTrieNode(child_table_index);
+    if (i < length) {
+      // Insert at i.
+      children_.InsertAt(i, reinterpret_cast<ProfileTrieNode*>(child));
+    } else {
+      // Add to end.
+      children_.Add(reinterpret_cast<ProfileTrieNode*>(child));
+    }
+    return child;
   }
-  int64_t  max_time() const { return max_time_; }
-
- private:
-  void VisitSample(intptr_t serial, ProcessedSample* sample) {
-    int64_t timestamp = sample->timestamp();
-    if (timestamp > max_time_) {
-      max_time_ = timestamp;
-    }
-    if (timestamp < min_time_) {
-      min_time_ = timestamp;
-    }
-
-    // Make sure VM tag is created.
-    if (VMTag::IsNativeEntryTag(sample->vm_tag())) {
-      CreateTag(VMTag::kNativeTagId);
-    } else if (VMTag::IsRuntimeEntryTag(sample->vm_tag())) {
-      CreateTag(VMTag::kRuntimeTagId);
-    }
-    CreateTag(sample->vm_tag());
-
-    // Make sure user tag is created.
-    CreateUserTag(sample->user_tag());
-
-    // Exclusive tick for top frame if the first frame was executing.
-    if (!sample->first_frame_executing()) {
-      Tick(sample->At(0), true, serial, timestamp);
-    }
-
-    // Inclusive tick for all frames.
-    for (intptr_t i = 0; i < sample->length(); i++) {
-      ASSERT(sample->At(i) != 0);
-      frames_++;
-      Tick(sample->At(i), false, serial, timestamp);
-    }
-  }
-
-  void CreateTag(uword tag) {
-    intptr_t index = tag_code_table_->FindIndex(tag);
-    if (index >= 0) {
-      // Already created.
-      return;
-    }
-    CodeRegion* region = new CodeRegion(CodeRegion::kTagCode,
-                                        tag,
-                                        tag + 1,
-                                        0,
-                                        null_code_);
-    index = tag_code_table_->InsertCodeRegion(region);
-    ASSERT(index >= 0);
-  }
-
-  void CreateUserTag(uword tag) {
-    if (tag == 0) {
-      // None set.
-      return;
-    }
-    return CreateTag(tag);
-  }
-
-  void Tick(uword pc, bool exclusive, intptr_t serial, int64_t timestamp) {
-    CodeRegionTable::TickResult r;
-    if (exclusive) {
-      // Exclusive ticks do not have an associated serial.
-      serial = -1;
-    }
-
-    r = live_code_table_->Tick(pc, exclusive, serial, timestamp);
-    if (r == CodeRegionTable::kTicked) {
-      // Live code found and ticked.
-      return;
-    }
-
-    if (r == CodeRegionTable::kNewerCode) {
-      // Code has been overwritten by newer code.
-      // Update shadow table of dead code regions.
-      r = dead_code_table_->Tick(pc, exclusive, serial, timestamp);
-      ASSERT(r != CodeRegionTable::kNewerCode);
-      if (r == CodeRegionTable::kTicked) {
-        // Dead code found and ticked.
-        return;
-      }
-      ASSERT(r == CodeRegionTable::kNotFound);
-      CreateAndTickDeadCodeRegion(pc, exclusive, serial);
-      return;
-    }
-
-    // Create new live CodeRegion.
-    ASSERT(r == CodeRegionTable::kNotFound);
-    CodeRegion* region = CreateCodeRegion(pc);
-    intptr_t index = live_code_table_->InsertCodeRegion(region);
-    ASSERT(index >= 0);
-    region = live_code_table_->At(index);
-    if (region->compile_timestamp() <= timestamp) {
-      region->Tick(pc, exclusive, serial);
-      return;
-    }
-
-    // We have created a new code region but it's for a CodeRegion
-    // compiled after the sample.
-    ASSERT(region->kind() == CodeRegion::kDartCode);
-    CreateAndTickDeadCodeRegion(pc, exclusive, serial);
-  }
-
-  void CreateAndTickDeadCodeRegion(uword pc, bool exclusive, intptr_t serial) {
-    // Need to create dead code.
-    CodeRegion* region = new CodeRegion(CodeRegion::kReusedCode,
-                                        pc,
-                                        pc + 1,
-                                        0,
-                                        null_code_);
-    intptr_t index = dead_code_table_->InsertCodeRegion(region);
-    ASSERT(index >= 0);
-    dead_code_table_->At(index)->Tick(pc, exclusive, serial);
-  }
-
-  CodeRegion* CreateCodeRegion(uword pc) {
-    const intptr_t kDartCodeAlignment = OS::PreferredCodeAlignment();
-    const intptr_t kDartCodeAlignmentMask = ~(kDartCodeAlignment - 1);
-    Code& code = Code::Handle(isolate_);
-
-    // Check current isolate for pc.
-    if (isolate_->heap()->CodeContains(pc)) {
-      code ^= Code::LookupCode(pc);
-      if (!code.IsNull()) {
-        deoptimized_code_->Add(code);
-        return new CodeRegion(CodeRegion::kDartCode,
-                              code.EntryPoint(),
-                              code.EntryPoint() + code.Size(),
-                              code.compile_timestamp(),
-                              code);
-      }
-      return new CodeRegion(CodeRegion::kCollectedCode,
-                            pc,
-                            (pc & kDartCodeAlignmentMask) + kDartCodeAlignment,
-                            0,
-                            code);
-    }
-
-    // Check VM isolate for pc.
-    if (vm_isolate_->heap()->CodeContains(pc)) {
-      code ^= Code::LookupCodeInVmIsolate(pc);
-      if (!code.IsNull()) {
-        return new CodeRegion(CodeRegion::kDartCode,
-                              code.EntryPoint(),
-                              code.EntryPoint() + code.Size(),
-                              code.compile_timestamp(),
-                              code);
-      }
-      return new CodeRegion(CodeRegion::kCollectedCode,
-                            pc,
-                            (pc & kDartCodeAlignmentMask) + kDartCodeAlignment,
-                            0,
-                            code);
-    }
-
-    // Check NativeSymbolResolver for pc.
-    uintptr_t native_start = 0;
-    char* native_name = NativeSymbolResolver::LookupSymbolName(pc,
-                                                               &native_start);
-    if (native_name == NULL) {
-      // No native name found.
-      return new CodeRegion(CodeRegion::kNativeCode,
-                            pc,
-                            pc + 1,
-                            0,
-                            code);
-    }
-    ASSERT(pc >= native_start);
-    CodeRegion* code_region =
-        new CodeRegion(CodeRegion::kNativeCode,
-                       native_start,
-                       pc + 1,
-                       0,
-                       code);
-    code_region->SetName(native_name);
-    free(native_name);
-    return code_region;
-  }
-
-  intptr_t frames_;
-  int64_t min_time_;
-  int64_t max_time_;
-  CodeRegionTable* live_code_table_;
-  CodeRegionTable* dead_code_table_;
-  CodeRegionTable* tag_code_table_;
-  Isolate* isolate_;
-  Isolate* vm_isolate_;
-  const Code& null_code_;
-  DeoptimizedCodeSet* deoptimized_code_;
-};
-
-
-class CodeRegionFunctionMapper : public ValueObject {
- public:
-  CodeRegionFunctionMapper(Isolate* isolate,
-                           CodeRegionTable* live_code_table,
-                           CodeRegionTable* dead_code_table,
-                           CodeRegionTable* tag_code_table,
-                           ProfileFunctionTable* function_table)
-      : isolate_(isolate),
-        live_code_table_(live_code_table),
-        dead_code_table_(dead_code_table),
-        tag_code_table_(tag_code_table),
-        function_table_(function_table) {
-    ASSERT(isolate_ != NULL);
-    ASSERT(live_code_table_ != NULL);
-    ASSERT(dead_code_table_ != NULL);
-    ASSERT(tag_code_table_ != NULL);
-    dead_code_table_offset_ = live_code_table_->Length();
-    tag_code_table_offset_ = dead_code_table_offset_ +
-                             dead_code_table_->Length();
-
-    const Code& null_code = Code::ZoneHandle();
-
-    // Create the truncated tag.
-    intptr_t truncated_index =
-        tag_code_table_->FindIndex(VMTag::kTruncatedTagId);
-    ASSERT(truncated_index < 0);
-    CodeRegion* truncated =
-        new CodeRegion(CodeRegion::kTagCode,
-                       VMTag::kTruncatedTagId,
-                       VMTag::kTruncatedTagId + 1,
-                       0,
-                       null_code);
-    truncated_index = tag_code_table_->InsertCodeRegion(truncated);
-    ASSERT(truncated_index >= 0);
-
-    // Create the root tag.
-    intptr_t root_index = tag_code_table_->FindIndex(VMTag::kRootTagId);
-    ASSERT(root_index < 0);
-    CodeRegion* root = new CodeRegion(CodeRegion::kTagCode,
-                                      VMTag::kRootTagId,
-                                      VMTag::kRootTagId + 1,
-                                      0,
-                                      null_code);
-    root_index = tag_code_table_->InsertCodeRegion(root);
-    ASSERT(root_index >= 0);
-  }
-
-  void Map() {
-    // Calculate final indexes in code table for each CodeRegion.
-    for (intptr_t i = 0; i < live_code_table_->Length(); i++) {
-      const intptr_t index = i;
-      CodeRegion* region = live_code_table_->At(i);
-      ASSERT(region != NULL);
-      region->set_code_table_index(index);
-    }
-
-    for (intptr_t i = 0; i < dead_code_table_->Length(); i++) {
-      const intptr_t index = dead_code_table_offset_ + i;
-      CodeRegion* region = dead_code_table_->At(i);
-      ASSERT(region != NULL);
-      region->set_code_table_index(index);
-    }
-
-    for (intptr_t i = 0; i < tag_code_table_->Length(); i++) {
-      const intptr_t index = tag_code_table_offset_ + i;
-      CodeRegion* region = tag_code_table_->At(i);
-      ASSERT(region != NULL);
-      region->set_code_table_index(index);
-    }
-
-    // Associate a ProfileFunction with each CodeRegion.
-    for (intptr_t i = 0; i < live_code_table_->Length(); i++) {
-      CodeRegion* region = live_code_table_->At(i);
-      ASSERT(region != NULL);
-      region->SetFunctionAndName(function_table_);
-    }
-
-    for (intptr_t i = 0; i < dead_code_table_->Length(); i++) {
-      CodeRegion* region = dead_code_table_->At(i);
-      ASSERT(region != NULL);
-      region->SetFunctionAndName(function_table_);
-    }
-
-    for (intptr_t i = 0; i < tag_code_table_->Length(); i++) {
-      CodeRegion* region = tag_code_table_->At(i);
-      ASSERT(region != NULL);
-      region->SetFunctionAndName(function_table_);
-    }
-  }
-
- private:
-  Isolate* isolate_;
-  CodeRegionTable* live_code_table_;
-  CodeRegionTable* dead_code_table_;
-  CodeRegionTable* tag_code_table_;
-  ProfileFunctionTable* function_table_;
-  intptr_t dead_code_table_offset_;
-  intptr_t tag_code_table_offset_;
 };
 
 
 class ProfileFunctionTrieNodeCode {
  public:
   explicit ProfileFunctionTrieNodeCode(intptr_t index)
       : code_index_(index),
         ticks_(0) {
   }
 
   intptr_t index() const {
     return code_index_;
   }
 
   void Tick() {
     ticks_++;
   }
 
   intptr_t ticks() const {
     return ticks_;
   }
 
  private:
   intptr_t code_index_;
   intptr_t ticks_;
 };
 
 
-class ProfileFunctionTrieNode : public ZoneAllocated {
+class ProfileFunctionTrieNode : public ProfileTrieNode {
  public:
-  explicit ProfileFunctionTrieNode(intptr_t profile_function_table_index)
-      : profile_function_table_index_(profile_function_table_index),
-        count_(0),
-        code_objects_(new ZoneGrowableArray<ProfileFunctionTrieNodeCode>()) {
+  explicit ProfileFunctionTrieNode(intptr_t table_index)
+      : ProfileTrieNode(table_index),
+        code_objects_(1) {
   }
 
-  void Tick() {
-    count_++;
+  void PrintToJSONArray(JSONArray* array) const {
+    ASSERT(array != NULL);
+    // Write CodeRegion index.
+    array->AddValue(table_index());
+    // Write count.
+    array->AddValue(count());
+    // Write number of code objects.
+    intptr_t code_count = code_objects_.length();
+    array->AddValue(code_count);
+    // Write each code object index and ticks.
+    for (intptr_t i = 0; i < code_count; i++) {
+      array->AddValue(code_objects_[i].index());
+      array->AddValue(code_objects_[i].ticks());
+    }
+    // Write number of children.
+    intptr_t child_count = children_.length();
+    array->AddValue(child_count);
+    // Recurse.
+    for (intptr_t i = 0; i < child_count; i++) {
+      children_[i]->PrintToJSONArray(array);
+    }
   }
 
-  intptr_t count() const {
-    return count_;
-  }
-
-  intptr_t profile_function_table_index() const {
-    return profile_function_table_index_;
-  }
-
-
-  ProfileFunctionTrieNode* GetChild(intptr_t child_index) {
-    const intptr_t length = children_.length();
+  ProfileFunctionTrieNode* GetChild(intptr_t child_table_index) {
+    const intptr_t length = NumChildren();
     intptr_t i = 0;
     while (i < length) {
-      ProfileFunctionTrieNode* child = children_[i];
-      if (child->profile_function_table_index() == child_index) {
+      ProfileFunctionTrieNode* child =
+          reinterpret_cast<ProfileFunctionTrieNode*>(children_[i]);
+      if (child->table_index() == child_table_index) {
         return child;
       }
-      if (child->profile_function_table_index() > child_index) {
+      if (child->table_index() > child_table_index) {
         break;
       }
       i++;
     }
-    // Add new ProfileFunctionTrieNode, sorted by index.
     ProfileFunctionTrieNode* child =
-        new ProfileFunctionTrieNode(child_index);
+        new ProfileFunctionTrieNode(child_table_index);
     if (i < length) {
       // Insert at i.
-      children_.InsertAt(i, child);
+      children_.InsertAt(i, reinterpret_cast<ProfileTrieNode*>(child));
     } else {
       // Add to end.
-      children_.Add(child);
+      children_.Add(reinterpret_cast<ProfileTrieNode*>(child));
     }
     return child;
   }
 
   void AddCodeObjectIndex(intptr_t index) {
-    for (intptr_t i = 0; i < code_objects_->length(); i++) {
-      ProfileFunctionTrieNodeCode& code_object = (*code_objects_)[i];
+    for (intptr_t i = 0; i < code_objects_.length(); i++) {
+      ProfileFunctionTrieNodeCode& code_object = code_objects_[i];
       if (code_object.index() == index) {
         code_object.Tick();
         return;
       }
     }
     ProfileFunctionTrieNodeCode code_object(index);
     code_object.Tick();
-    code_objects_->Add(code_object);
-  }
-
-  // This should only be called after the trie is completely built.
-  void SortByCount() {
-    code_objects_->Sort(ProfileFunctionTrieNodeCodeCompare);
-    children_.Sort(ProfileFunctionTrieNodeCompare);
-    intptr_t child_count = children_.length();
-    // Recurse.
-    for (intptr_t i = 0; i < child_count; i++) {
-      children_[i]->SortByCount();
-    }
-  }
-
-  void PrintToJSONArray(JSONArray* array) const {
-    ASSERT(array != NULL);
-    // Write CodeRegion index.
-    array->AddValue(profile_function_table_index_);
-    // Write count.
-    array->AddValue(count_);
-    // Write number of code objects.
-    intptr_t code_count = code_objects_->length();
-    array->AddValue(code_count);
-    // Write each code object index and ticks.
-    for (intptr_t i = 0; i < code_count; i++) {
-      array->AddValue((*code_objects_)[i].index());
-      array->AddValue((*code_objects_)[i].ticks());
-    }
-    // Write number of children.
-    intptr_t child_count = children_.length();
-    array->AddValue(child_count);
-    // Recurse.
-    for (intptr_t i = 0; i < child_count; i++) {
-      children_[i]->PrintToJSONArray(array);
-    }
+    code_objects_.Add(code_object);
   }
 
  private:
-  static int ProfileFunctionTrieNodeCodeCompare(
-      const ProfileFunctionTrieNodeCode* a,
-      const ProfileFunctionTrieNodeCode* b) {
-    ASSERT(a != NULL);
-    ASSERT(b != NULL);
-    return b->ticks() - a->ticks();
-  }
-
-  static int ProfileFunctionTrieNodeCompare(ProfileFunctionTrieNode* const* a,
-                                            ProfileFunctionTrieNode* const* b) {
-    ASSERT(a != NULL);
-    ASSERT(b != NULL);
-    return (*b)->count() - (*a)->count();
-  }
-
-  const intptr_t profile_function_table_index_;
-  intptr_t count_;
-  ZoneGrowableArray<ProfileFunctionTrieNode*> children_;
-  ZoneGrowableArray<ProfileFunctionTrieNodeCode>* code_objects_;
+  ZoneGrowableArray<ProfileFunctionTrieNodeCode> code_objects_;
 };
 
 
-class TrieBuilder : public ValueObject {
+class ProfileBuilder : public ValueObject {
  public:
-  TrieBuilder(CodeRegionTable* live_code_table,
-              CodeRegionTable* dead_code_table,
-              CodeRegionTable* tag_code_table)
-      : live_code_table_(live_code_table),
-        dead_code_table_(dead_code_table),
-        tag_code_table_(tag_code_table) {
-    ASSERT(live_code_table_ != NULL);
-    ASSERT(dead_code_table_ != NULL);
-    ASSERT(tag_code_table_ != NULL);
-  }
-
-  ProfilerService::TagOrder tag_order() const {
-    return tag_order_;
-  }
-
-  void set_tag_order(ProfilerService::TagOrder tag_order) {
-    tag_order_ = tag_order;
-  }
-
- protected:
-  intptr_t FindTagIndex(uword tag) const {
-    if (tag == 0) {
-      UNREACHABLE();
-      return -1;
-    }
-    intptr_t index = tag_code_table_->FindIndex(tag);
-    if (index < 0) {
-      UNREACHABLE();
-      return -1;
-    }
-    ASSERT(index >= 0);
-    CodeRegion* region = tag_code_table_->At(index);
-    ASSERT(region->contains(tag));
-    return region->code_table_index();
-  }
-
-  intptr_t FindDeadIndex(uword pc, int64_t timestamp) const {
-    intptr_t index = dead_code_table_->FindIndex(pc);
-    if (index < 0) {
-      OS::Print("%" Px " cannot be found\n", pc);
-      return -1;
-    }
-    CodeRegion* region = dead_code_table_->At(index);
-    ASSERT(region->contains(pc));
-    ASSERT(region->compile_timestamp() <= timestamp);
-    return region->code_table_index();
-  }
-
-  intptr_t FindFinalIndex(uword pc, int64_t timestamp) const {
-    intptr_t index = live_code_table_->FindIndex(pc);
-    if (index < 0) {
-      // Try dead code table.
-      return FindDeadIndex(pc, timestamp);
-    }
-    CodeRegion* region = live_code_table_->At(index);
-    ASSERT(region->contains(pc));
-    if (region->compile_timestamp() > timestamp) {
-      // Overwritten code, find in dead code table.
-      return FindDeadIndex(pc, timestamp);
-    }
-    ASSERT(region->compile_timestamp() <= timestamp);
-    return region->code_table_index();
-  }
-
-  bool vm_tags_emitted() const {
-    return (tag_order_ == ProfilerService::kUserVM) ||
-           (tag_order_ == ProfilerService::kVMUser) ||
-           (tag_order_ == ProfilerService::kVM);
-  }
-
-  CodeRegion* FindCodeObject(uword pc, int64_t timestamp) const {
-    intptr_t index = live_code_table_->FindIndex(pc);
-    if (index < 0) {
-      return NULL;
-    }
-    CodeRegion* region = live_code_table_->At(index);
-    ASSERT(region->contains(pc));
-    if (region->compile_timestamp() > timestamp) {
-      // Overwritten code, find in dead code table.
-      index = dead_code_table_->FindIndex(pc);
-      if (index < 0) {
-        return NULL;
-      }
-      region = dead_code_table_->At(index);
-      ASSERT(region->contains(pc));
-      ASSERT(region->compile_timestamp() <= timestamp);
-      return region;
-    }
-    ASSERT(region->compile_timestamp() <= timestamp);
-    return region;
-  }
-
-  CodeRegionTable* live_code_table_;
-  CodeRegionTable* dead_code_table_;
-  CodeRegionTable* tag_code_table_;
-  ProfilerService::TagOrder tag_order_;
-};
-
-
-class ProfileFunctionTrieBuilder : public TrieBuilder {
- public:
-  ProfileFunctionTrieBuilder(CodeRegionTable* live_code_table,
-                             CodeRegionTable* dead_code_table,
-                             CodeRegionTable* tag_code_table,
-                             ProfileFunctionTable* function_table)
-      : TrieBuilder(live_code_table, dead_code_table, tag_code_table),
-        function_table_(function_table),
-        inclusive_tree_(false) {
-    ASSERT(function_table_ != NULL);
-    set_tag_order(ProfilerService::kUserVM);
-
-    // Verify that the truncated tag exists.
-    ASSERT(tag_code_table_->FindIndex(VMTag::kTruncatedTagId) >= 0);
-
-    // Verify that the root tag exists.
-    intptr_t root_index = tag_code_table_->FindIndex(VMTag::kRootTagId);
-    ASSERT(root_index >= 0);
-
-    // Setup root.
-    CodeRegion* region = tag_code_table_->At(root_index);
-    ASSERT(region != NULL);
-    ProfileFunction* function = region->function();
-    ASSERT(function != NULL);
-
-    exclusive_root_ = new ProfileFunctionTrieNode(function->index());
-    inclusive_root_ = new ProfileFunctionTrieNode(function->index());
-  }
-
-  void VisitSample(intptr_t sample_idx, ProcessedSample* sample) {
-    inclusive_tree_ = false;
-    ProcessSampleExclusive(sample_idx, sample);
-    inclusive_tree_ = true;
-    ProcessSampleInclusive(sample_idx, sample);
-  }
-
-  void Build(ProcessedSampleBuffer* buffer) {
-    for (intptr_t i = 0; i < buffer->length(); i++) {
-      ProcessedSample* sample = buffer->At(i);
-      VisitSample(i, sample);
-    }
-  }
-
-  ProfileFunctionTrieNode* exclusive_root() const {
-    return exclusive_root_;
-  }
-
-  ProfileFunctionTrieNode* inclusive_root() const {
-    return inclusive_root_;
-  }
-
-  ProfilerService::TagOrder tag_order() const {
-    return tag_order_;
-  }
-
-  bool vm_tags_emitted() const {
-    return (tag_order_ == ProfilerService::kUserVM) ||
-           (tag_order_ == ProfilerService::kVMUser) ||
-           (tag_order_ == ProfilerService::kVM);
-  }
-
-  void set_tag_order(ProfilerService::TagOrder tag_order) {
-    tag_order_ = tag_order;
+  ProfileBuilder(Isolate* isolate,
+                 SampleFilter* filter,
+                 Profile::TagOrder tag_order,
+                 Profile* profile)
+      : isolate_(isolate),
+        vm_isolate_(Dart::vm_isolate()),
+        filter_(filter),
+        tag_order_(tag_order),
+        profile_(profile),
+        deoptimized_code_(new DeoptimizedCodeSet(isolate)),
+        null_code_(Code::ZoneHandle()),
+        null_function_(Function::ZoneHandle()),
+        tick_functions_(false),
+        samples_(NULL) {
+    ASSERT(profile_ != NULL);
+  }
+
+  void Build() {
+    ScopeTimer sw("ProfileBuilder::Build", FLAG_trace_profiler);
+    FilterSamples();
+
+    Setup();
+    BuildCodeTable();
+    FinalizeCodeIndexes();
+    BuildFunctionTable();
+
+    BuildCodeTrie(Profile::kExclusiveCode);
+    BuildCodeTrie(Profile::kInclusiveCode);
+
+    BuildFunctionTrie(Profile::kExclusiveFunction);
+    BuildFunctionTrie(Profile::kInclusiveFunction);
   }
 
  private:
-  void ProcessSampleInclusive(intptr_t sample_idx, ProcessedSample* sample) {
-    // Give the root a tick.
-    inclusive_root_->Tick();
-    ProfileFunctionTrieNode* current = inclusive_root_;
-    current = AppendTags(sample, current);
-    if (sample->truncated()) {
-      InclusiveTickTruncatedTag();
-      current = AppendTruncatedTag(current);
-    }
-    // Walk the sampled PCs.
-    for (intptr_t i = sample->length() - 1; i >= 0; i--) {
-      ASSERT(sample->At(i) != 0);
-      current = ProcessPC(sample->At(i),
-                          sample->timestamp(),
-                          current,
-                          sample_idx,
-                          (i == 0),
-                          !sample->first_frame_executing() && (i == 0));
-    }
-  }
-
-  void ProcessSampleExclusive(intptr_t sample_idx, ProcessedSample* sample) {
-    // Give the root a tick.
-    exclusive_root_->Tick();
-    ProfileFunctionTrieNode* current = exclusive_root_;
-    current = AppendTags(sample, current);
-    // Walk the sampled PCs.
-    for (intptr_t i = 0; i < sample->length(); i++) {
-      ASSERT(sample->At(i) != 0);
-      current = ProcessPC(sample->At(i),
-                          sample->timestamp(),
-                          current,
-                          sample_idx,
-                          (i == 0),
-                          !sample->first_frame_executing() && (i == 0));
-    }
-    if (sample->truncated()) {
-      current = AppendTruncatedTag(current);
-    }
-  }
-
-  ProfileFunctionTrieNode* AppendUserTag(ProcessedSample* sample,
-                                         ProfileFunctionTrieNode* current) {
-    intptr_t user_tag_index = FindTagFunctionIndex(sample->user_tag());
-    if (user_tag_index >= 0) {
-      current = current->GetChild(user_tag_index);
-      // Give the tag a tick.
+  static bool IsInclusiveTrie(Profile::TrieKind kind) {
+    return (kind == Profile::kInclusiveFunction) ||
+           (kind == Profile::kInclusiveCode);
+  }
+
+  void Setup() {
+    profile_->live_code_ = new ProfileCodeTable();
+    profile_->dead_code_ = new ProfileCodeTable();
+    profile_->tag_code_ = new ProfileCodeTable();
+    profile_->functions_ = new ProfileFunctionTable();
+    // Register some synthetic tags.
+    RegisterProfileCodeTag(VMTag::kRootTagId);
+    RegisterProfileCodeTag(VMTag::kTruncatedTagId);
+  }
+
+  void FilterSamples() {
+    ScopeTimer sw("ProfileBuilder::FilterSamples", FLAG_trace_profiler);
+    MutexLocker profiler_data_lock(isolate_->profiler_data_mutex());
+    IsolateProfilerData* profiler_data = isolate_->profiler_data();
+    if (profiler_data == NULL) {
+      return;
+    }
+    SampleBuffer* sample_buffer = profiler_data->sample_buffer();
+    if (sample_buffer == NULL) {
+      return;
+    }
+    samples_ = sample_buffer->BuildProcessedSampleBuffer(filter_);
+    profile_->sample_count_ = samples_->length();
+  }
+
+  void UpdateMinMaxTimes(int64_t timestamp) {
+    profile_->min_time_ =
+        timestamp < profile_->min_time_ ? timestamp : profile_->min_time_;
+    profile_->max_time_ =
+        timestamp > profile_->max_time_ ? timestamp : profile_->max_time_;
+  }
+
+  void BuildCodeTable() {
+    ScopeTimer sw("ProfileBuilder::BuildCodeTable", FLAG_trace_profiler);
+    for (intptr_t i = 0; i < samples_->length(); i++) {
+      ProcessedSample* sample = samples_->At(i);
+      const int64_t timestamp = sample->timestamp();
+
+      // This is our first pass over the sample buffer, use this as an
+      // opportunity to determine the min and max time ranges of this profile.
+      UpdateMinMaxTimes(timestamp);
+
+      // Make sure VM tag exists.
+      if (VMTag::IsNativeEntryTag(sample->vm_tag())) {
+        RegisterProfileCodeTag(VMTag::kNativeTagId);
+      } else if (VMTag::IsRuntimeEntryTag(sample->vm_tag())) {
+        RegisterProfileCodeTag(VMTag::kRuntimeTagId);
+      }
+      RegisterProfileCodeTag(sample->vm_tag());
+      // Make sure user tag exists.
+      RegisterProfileCodeTag(sample->user_tag());
+
+      // Make sure that a ProfileCode objects exist for all pcs in the sample
+      // and tick each one.
+      for (intptr_t i = 0; i < sample->length(); i++) {
+        const uword pc = sample->At(i);
+        ASSERT(pc != 0);
+        ProfileCode* code = RegisterProfileCode(pc, timestamp);
+        ASSERT(code != NULL);
+        code->Tick(pc, (i == 0), i);
+      }
+    }
+  }
+
+  void FinalizeCodeIndexes() {
+    ScopeTimer sw("ProfileBuilder::FinalizeCodeIndexes", FLAG_trace_profiler);
+    ProfileCodeTable* live_table = profile_->live_code_;
+    ProfileCodeTable* dead_table = profile_->dead_code_;
+    ProfileCodeTable* tag_table = profile_->tag_code_;
+    const intptr_t dead_code_index_offset = live_table->length();
+    const intptr_t tag_code_index_offset =
+        dead_table->length() + dead_code_index_offset;
+
+    profile_->dead_code_index_offset_ = dead_code_index_offset;
+    profile_->tag_code_index_offset_ = tag_code_index_offset;
+
+    for (intptr_t i = 0; i < live_table->length(); i++) {
+      const intptr_t index = i;
+      ProfileCode* code = live_table->At(i);
+      ASSERT(code != NULL);
+      code->set_code_table_index(index);
+    }
+
+    for (intptr_t i = 0; i < dead_table->length(); i++) {
+      const intptr_t index = dead_code_index_offset + i;
+      ProfileCode* code = dead_table->At(i);
+      ASSERT(code != NULL);
+      code->set_code_table_index(index);
+    }
+
+    for (intptr_t i = 0; i < tag_table->length(); i++) {
+      const intptr_t index = tag_code_index_offset + i;
+      ProfileCode* code = tag_table->At(i);
+      ASSERT(code != NULL);
+      code->set_code_table_index(index);
+    }
+  }
+
+  void BuildFunctionTable() {
+    ScopeTimer sw("ProfileBuilder::BuildFunctionTable", FLAG_trace_profiler);
+    ProfileCodeTable* live_table = profile_->live_code_;
+    ProfileCodeTable* dead_table = profile_->dead_code_;
+    ProfileCodeTable* tag_table = profile_->tag_code_;
+    ProfileFunctionTable* function_table = profile_->functions_;
+    for (intptr_t i = 0; i < live_table->length(); i++) {
+      ProfileCode* code = live_table->At(i);
+      ASSERT(code != NULL);
+      code->SetFunctionAndName(function_table);
+    }
+
+    for (intptr_t i = 0; i < dead_table->length(); i++) {
+      ProfileCode* code = dead_table->At(i);
+      ASSERT(code != NULL);
+      code->SetFunctionAndName(function_table);
+    }
+
+    for (intptr_t i = 0; i < tag_table->length(); i++) {
+      ProfileCode* code = tag_table->At(i);
+      ASSERT(code != NULL);
+      code->SetFunctionAndName(function_table);
+    }
+  }
+
+  void BuildCodeTrie(Profile::TrieKind kind) {
+    ProfileCodeTrieNode* root =
+        new ProfileCodeTrieNode(GetProfileCodeTagIndex(VMTag::kRootTagId));
+    if (IsInclusiveTrie(kind)) {
+      BuildInclusiveCodeTrie(root);
+    } else {
+      BuildExclusiveCodeTrie(root);
+    }
+    root->SortChildren();
+    profile_->roots_[static_cast<intptr_t>(kind)] = root;
+  }
+
+  void BuildInclusiveCodeTrie(ProfileCodeTrieNode* root) {
+    ScopeTimer sw("ProfileBuilder::BuildInclusiveCodeTrie",
+                  FLAG_trace_profiler);
+    for (intptr_t i = 0; i < samples_->length(); i++) {
+      ProcessedSample* sample = samples_->At(i);
+
+      // Tick the root.
+      ProfileCodeTrieNode* current = root;
       current->Tick();
-    }
-    return current;
-  }
-
-
-  ProfileFunctionTrieNode* AppendTruncatedTag(
-      ProfileFunctionTrieNode* current) {
-    intptr_t truncated_tag_index = FindTagFunctionIndex(VMTag::kTruncatedTagId);
-    ASSERT(truncated_tag_index >= 0);
-    current = current->GetChild(truncated_tag_index);
-    current->Tick();
-    return current;
-  }
-
-  void InclusiveTickTruncatedTag() {
-    intptr_t index = tag_code_table_->FindIndex(VMTag::kTruncatedTagId);
-    CodeRegion* region = tag_code_table_->At(index);
-    ProfileFunction* function = region->function();
-    function->inc_inclusive_ticks();
-  }
-
-  ProfileFunctionTrieNode* AppendVMTag(ProcessedSample* sample,
-                                       ProfileFunctionTrieNode* current) {
-    if (VMTag::IsNativeEntryTag(sample->vm_tag())) {
-      // Insert a dummy kNativeTagId node.
-      intptr_t tag_index = FindTagFunctionIndex(VMTag::kNativeTagId);
-      current = current->GetChild(tag_index);
-      // Give the tag a tick.
+
+      // VM & User tags.
+      current = AppendTags(sample->vm_tag(), sample->user_tag(), current);
+
+      // Truncated tag.
+      if (sample->truncated()) {
+        current = AppendTruncatedTag(current);
+      }
+
+      // Walk the sampled PCs.
+      for (intptr_t j = sample->length() - 1; j >= 0; j--) {
+        ASSERT(sample->At(j) != 0);
+        intptr_t index =
+            GetProfileCodeIndex(sample->At(j), sample->timestamp());
+        ASSERT(index >= 0);
+        current = current->GetChild(index);
+        current->Tick();
+      }
+    }
+  }
+
+  void BuildExclusiveCodeTrie(ProfileCodeTrieNode* root) {
+    ScopeTimer sw("ProfileBuilder::BuildExclusiveCodeTrie",
+                  FLAG_trace_profiler);
+    for (intptr_t i = 0; i < samples_->length(); i++) {
+      ProcessedSample* sample = samples_->At(i);
+
+      // Tick the root.
+      ProfileCodeTrieNode* current = root;
       current->Tick();
-    } else if (VMTag::IsRuntimeEntryTag(sample->vm_tag())) {
-      // Insert a dummy kRuntimeTagId node.
-      intptr_t tag_index = FindTagFunctionIndex(VMTag::kRuntimeTagId);
-      current = current->GetChild(tag_index);
-      // Give the tag a tick.
+
+      // VM & User tags.
+      current = AppendTags(sample->vm_tag(), sample->user_tag(), current);
+
+      // Walk the sampled PCs.
+      for (intptr_t j = 0; j < sample->length(); j++) {
+        ASSERT(sample->At(j) != 0);
+        intptr_t index =
+            GetProfileCodeIndex(sample->At(j), sample->timestamp());
+        ASSERT(index >= 0);
+        current = current->GetChild(index);
+
+        if (j == 0) {
+          // Executing PC.
+          if (!sample->first_frame_executing() || vm_tags_emitted()) {
+            // Only tick if this isn't an exit frame or VM tags are emitted.
+            current->Tick();
+          }
+        } else {
+          // Caller PCs.
+          current->Tick();
+        }
+
+        current->Tick();
+      }
+
+      // Truncated tag.
+      if (sample->truncated()) {
+        current = AppendTruncatedTag(current);
+      }
+    }
+  }
+
+  void BuildFunctionTrie(Profile::TrieKind kind) {
+    ProfileFunctionTrieNode* root =
+        new ProfileFunctionTrieNode(
+            GetProfileFunctionTagIndex(VMTag::kRootTagId));
+    // We tick the functions while building the trie, but, we don't want to do
+    // it for both tries, just one.
+    tick_functions_ = IsInclusiveTrie(kind);
+    if (IsInclusiveTrie(kind)) {
+      BuildInclusiveFunctionTrie(root);
+    } else {
+      BuildExclusiveFunctionTrie(root);
+    }
+    root->SortChildren();
+    profile_->roots_[static_cast<intptr_t>(kind)] = root;
+  }
+
+  void BuildInclusiveFunctionTrie(ProfileFunctionTrieNode* root) {
+    ScopeTimer sw("ProfileBuilder::BuildInclusiveFunctionTrie",
+                  FLAG_trace_profiler);
+    for (intptr_t i = 0; i < samples_->length(); i++) {
+      ProcessedSample* sample = samples_->At(i);
+
+      // Tick the root.
+      ProfileFunctionTrieNode* current = root;
       current->Tick();
-    } else {
-      intptr_t tag_index = FindTagFunctionIndex(sample->vm_tag());
-      current = current->GetChild(tag_index);
-      // Give the tag a tick.
+
+      // VM & User tags.
+      current = AppendTags(sample->vm_tag(), sample->user_tag(), current);
+
+      // Truncated tag.
+      if (sample->truncated()) {
+        current = AppendTruncatedTag(current);
+        InclusiveTickTruncatedTag();
+      }
+
+      // Walk the sampled PCs.
+      for (intptr_t j = sample->length() - 1; j >= 0; j--) {
+        ASSERT(sample->At(j) != 0);
+        current = ProcessFunctionPC(
+            sample->At(j),
+            sample->timestamp(),
+            current,
+            i,
+            (j == 0),
+            sample->first_frame_executing(),
+            true);
+      }
+    }
+  }
+
+  void BuildExclusiveFunctionTrie(ProfileFunctionTrieNode* root) {
+    ScopeTimer sw("ProfileBuilder::BuildExclusiveFunctionTrie",
+                  FLAG_trace_profiler);
+    for (intptr_t i = 0; i < samples_->length(); i++) {
+      ProcessedSample* sample = samples_->At(i);
+
+      // Tick the root.
+      ProfileFunctionTrieNode* current = root;
       current->Tick();
-    }
-    return current;
-  }
-
-  ProfileFunctionTrieNode* AppendSpecificNativeRuntimeEntryVMTag(
-      ProcessedSample* sample, ProfileFunctionTrieNode* current) {
-    // Only Native and Runtime entries have a second VM tag.
-    if (!VMTag::IsNativeEntryTag(sample->vm_tag()) &&
-        !VMTag::IsRuntimeEntryTag(sample->vm_tag())) {
-      return current;
-    }
-    intptr_t tag_index = FindTagFunctionIndex(sample->vm_tag());
-    current = current->GetChild(tag_index);
-    // Give the tag a tick.
-    current->Tick();
-    return current;
-  }
-
-  ProfileFunctionTrieNode* AppendVMTags(ProcessedSample* sample,
-                                        ProfileFunctionTrieNode* current) {
-    current = AppendVMTag(sample, current);
-    current = AppendSpecificNativeRuntimeEntryVMTag(sample, current);
-    return current;
-  }
-
-  ProfileFunctionTrieNode* AppendTags(ProcessedSample* sample,
-                                      ProfileFunctionTrieNode* current) {
-    // None.
-    if (tag_order() == ProfilerService::kNoTags) {
-      return current;
-    }
-    // User first.
-    if ((tag_order() == ProfilerService::kUserVM) ||
-        (tag_order() == ProfilerService::kUser)) {
-      current = AppendUserTag(sample, current);
-      // Only user.
-      if (tag_order() == ProfilerService::kUser) {
-        return current;
-      }
-      return AppendVMTags(sample, current);
-    }
-    // VM first.
-    ASSERT((tag_order() == ProfilerService::kVMUser) ||
-           (tag_order() == ProfilerService::kVM));
-    current = AppendVMTags(sample, current);
-    // Only VM.
-    if (tag_order() == ProfilerService::kVM) {
-      return current;
-    }
-    return AppendUserTag(sample, current);
-  }
-
-  intptr_t FindTagFunctionIndex(uword tag) const {
-    if (tag == 0) {
-      UNREACHABLE();
-      return -1;
-    }
-    intptr_t index = tag_code_table_->FindIndex(tag);
-    if (index < 0) {
-      UNREACHABLE();
-      return -1;
-    }
-    ASSERT(index >= 0);
-    CodeRegion* region = tag_code_table_->At(index);
-    ASSERT(region->contains(tag));
-    ProfileFunction* function = region->function();
-    ASSERT(function != NULL);
-    return function->index();
-  }
-
-  void Dump(ProfileFunctionTrieNode* current) {
-    int current_index = current->profile_function_table_index();
-    ProfileFunction* function = function_table_->At(current_index);
-    function->Dump();
-    OS::Print("\n");
-  }
-
-  ProfileFunctionTrieNode* ProcessPC(uword pc,
-                                     int64_t timestamp,
-                                     ProfileFunctionTrieNode* current,
-                                     intptr_t inclusive_serial,
-                                     bool top_frame,
-                                     bool exit_frame) {
-    CodeRegion* region = FindCodeObject(pc, timestamp);
-    if (region == NULL) {
-      return current;
-    }
-    const char* region_name = region->name();
-    if (region_name == NULL) {
-      region_name = "";
-    }
-    intptr_t code_index = region->code_table_index();
-    const Code& code = Code::ZoneHandle(region->code());
+
+      // VM & User tags.
+      current = AppendTags(sample->vm_tag(), sample->user_tag(), current);
+
+      // Walk the sampled PCs.
+      for (intptr_t j = 0; j < sample->length(); j++) {
+        ASSERT(sample->At(j) != 0);
+        current = ProcessFunctionPC(
+            sample->At(j),
+            sample->timestamp(),
+            current,
+            i,
+            (j == 0),
+            sample->first_frame_executing(),
+            false);
+      }
+
+      // Truncated tag.
+      if (sample->truncated()) {
+        current = AppendTruncatedTag(current);
+      }
+    }
+  }
+
+  ProfileFunctionTrieNode* ProcessFunctionPC(
+      uword pc,
+      int64_t timestamp,
+      ProfileFunctionTrieNode* current,
+      intptr_t inclusive_serial,
+      bool top_frame,
+      bool top_frame_executing,
+      bool inclusive_tree) {
+    ProfileCode* profile_code = GetProfileCode(pc, timestamp);
+    ASSERT(profile_code != NULL);
+    const char* code_name = profile_code->name();
+    if (code_name == NULL) {
+      code_name = "";
+    }
+    intptr_t code_index = profile_code->code_table_index();
+    const Code& code = Code::ZoneHandle(profile_code->code());
     GrowableArray<Function*> inlined_functions;
     if (!code.IsNull()) {
       intptr_t offset = pc - code.EntryPoint();
       code.GetInlinedFunctionsAt(offset, &inlined_functions);
     }
     if (code.IsNull() || (inlined_functions.length() == 0)) {
       // No inlined functions.
-      ProfileFunction* function = region->function();
+      ProfileFunction* function = profile_code->function();
       ASSERT(function != NULL);
       current = ProcessFunction(function,
                                 current,
                                 inclusive_serial,
                                 top_frame,
-                                exit_frame,
+                                top_frame_executing,
                                 code_index);
       return current;
     }
 
-    if (inclusive_tree_) {
+    if (inclusive_tree) {
       for (intptr_t i = inlined_functions.length() - 1; i >= 0; i--) {
         Function* inlined_function = inlined_functions[i];
         ASSERT(inlined_function != NULL);
         ASSERT(!inlined_function->IsNull());
         current = ProcessInlinedFunction(inlined_function,
                                          current,
                                          inclusive_serial,
                                          top_frame,
-                                         exit_frame,
+                                         top_frame_executing,
                                          code_index);
         top_frame = false;
       }
     } else {
       for (intptr_t i = 0; i < inlined_functions.length(); i++) {
         Function* inlined_function = inlined_functions[i];
         ASSERT(inlined_function != NULL);
         ASSERT(!inlined_function->IsNull());
         current = ProcessInlinedFunction(inlined_function,
                                          current,
                                          inclusive_serial,
                                          top_frame,
-                                         exit_frame,
+                                         top_frame_executing,
                                          code_index);
         top_frame = false;
       }
     }
 
     return current;
   }
 
   ProfileFunctionTrieNode* ProcessInlinedFunction(
       Function* inlined_function,
       ProfileFunctionTrieNode* current,
       intptr_t inclusive_serial,
       bool top_frame,
-      bool exit_frame,
+      bool top_frame_executing,
       intptr_t code_index) {
-    ProfileFunction* function =
-        function_table_->LookupOrAdd(*inlined_function);
+    ProfileFunctionTable* function_table = profile_->functions_;
+    ProfileFunction* function = function_table->LookupOrAdd(*inlined_function);
     ASSERT(function != NULL);
     return ProcessFunction(function,
                            current,
                            inclusive_serial,
                            top_frame,
-                           exit_frame,
+                           top_frame_executing,
                            code_index);
   }
 
   ProfileFunctionTrieNode* ProcessFunction(ProfileFunction* function,
                                            ProfileFunctionTrieNode* current,
                                            intptr_t inclusive_serial,
                                            bool top_frame,
-                                           bool exit_frame,
+                                           bool top_frame_executing,
                                            intptr_t code_index) {
-    const bool exclusive = top_frame && !exit_frame;
-    if (!inclusive_tree_) {
-      // We process functions for the inclusive and exclusive trees.
-      // Only tick the function for the exclusive tree.
+    const bool exclusive = top_frame && top_frame_executing;
+    if (tick_functions_) {
       function->Tick(exclusive, exclusive ? -1 : inclusive_serial);
     }
-    function->AddCodeObjectIndex(code_index);
-    current = current->GetChild(function->index());
+    function->AddProfileCode(code_index);
+    current = current->GetChild(function->table_index());
     current->AddCodeObjectIndex(code_index);
     if (top_frame) {
-      if (!exit_frame || vm_tags_emitted()) {
-        // Only tick if this isn't an exit frame or VM tags are emitted.
+      if (top_frame_executing || vm_tags_emitted()) {
+        // Only tick if this function is using CPU time or VM tags are emitted.
         current->Tick();
       }
     } else {
       current->Tick();
     }
     return current;
   }
 
-  ProfileFunctionTrieNode* exclusive_root_;
-  ProfileFunctionTrieNode* inclusive_root_;
-  ProfileFunctionTable* function_table_;
-  bool inclusive_tree_;
-};
+  // Tick the truncated tag's inclusive tick count.
+  void InclusiveTickTruncatedTag() {
+    ProfileCodeTable* tag_table = profile_->tag_code_;
+    intptr_t index = tag_table->FindCodeIndexForPC(VMTag::kTruncatedTagId);
+    ASSERT(index >= 0);
+    ProfileCode* code = tag_table->At(index);
+    code->IncInclusiveTicks();
+    ASSERT(code != NULL);
+    ProfileFunction* function = code->function();
+    function->IncInclusiveTicks();
+  }
 
 
-class CodeRegionTrieNode : public ZoneAllocated {
- public:
-  explicit CodeRegionTrieNode(intptr_t code_region_index)
-      : code_region_index_(code_region_index),
-        count_(0),
-        children_(new ZoneGrowableArray<CodeRegionTrieNode*>()) {
+  // Tag append functions are overloaded for |ProfileCodeTrieNode| and
+  // |ProfileFunctionTrieNode| types.
+
+  // ProfileCodeTrieNode
+  ProfileCodeTrieNode* AppendUserTag(uword user_tag,
+                                     ProfileCodeTrieNode* current) {
+    intptr_t user_tag_index = GetProfileCodeTagIndex(user_tag);
+    if (user_tag_index >= 0) {
+      current = current->GetChild(user_tag_index);
+      current->Tick();
+    }
+    return current;
   }
 
-  void Tick() {
-    ASSERT(code_region_index_ >= 0);
-    count_++;
+  ProfileCodeTrieNode* AppendTruncatedTag(ProfileCodeTrieNode* current) {
+    intptr_t truncated_tag_index =
+        GetProfileCodeTagIndex(VMTag::kTruncatedTagId);
+    ASSERT(truncated_tag_index >= 0);
+    current = current->GetChild(truncated_tag_index);
+    current->Tick();
+    return current;
   }
 
-  intptr_t count() const {
-    ASSERT(code_region_index_ >= 0);
-    return count_;
-  }
-
-  intptr_t code_region_index() const {
-    return code_region_index_;
-  }
-
-  ZoneGrowableArray<CodeRegionTrieNode*>& children() const {
-    return *children_;
-  }
-
-  CodeRegionTrieNode* GetChild(intptr_t child_code_region_index) {
-    const intptr_t length = children_->length();
-    intptr_t i = 0;
-    while (i < length) {
-      CodeRegionTrieNode* child = (*children_)[i];
-      if (child->code_region_index() == child_code_region_index) {
-        return child;
-      }
-      if (child->code_region_index() > child_code_region_index) {
-        break;
-      }
-      i++;
-    }
-    // Add new CodeRegion, sorted by CodeRegionTable index.
-    CodeRegionTrieNode* child = new CodeRegionTrieNode(child_code_region_index);
-    if (i < length) {
-      // Insert at i.
-      children_->InsertAt(i, child);
+  ProfileCodeTrieNode* AppendVMTag(uword vm_tag,
+                                   ProfileCodeTrieNode* current) {
+    if (VMTag::IsNativeEntryTag(vm_tag)) {
+      // Insert a dummy kNativeTagId node.
+      intptr_t tag_index = GetProfileCodeTagIndex(VMTag::kNativeTagId);
+      current = current->GetChild(tag_index);
+      // Give the tag a tick.
+      current->Tick();
+    } else if (VMTag::IsRuntimeEntryTag(vm_tag)) {
+      // Insert a dummy kRuntimeTagId node.
+      intptr_t tag_index = GetProfileCodeTagIndex(VMTag::kRuntimeTagId);
+      current = current->GetChild(tag_index);
+      // Give the tag a tick.
+      current->Tick();
     } else {
-      // Add to end.
-      children_->Add(child);
-    }
-    return child;
-  }
-
-  // This should only be called after the trie is completely built.
-  void SortByCount() {
-    children_->Sort(CodeRegionTrieNodeCompare);
-    ZoneGrowableArray<CodeRegionTrieNode*>& kids = children();
-    intptr_t child_count = kids.length();
-    // Recurse.
-    for (intptr_t i = 0; i < child_count; i++) {
-      kids[i]->SortByCount();
-    }
-  }
-
-  void PrintToJSONArray(JSONArray* array) const {
-    ASSERT(array != NULL);
-    // Write CodeRegion index.
-    array->AddValue(code_region_index_);
-    // Write count.
-    array->AddValue(count_);
-    // Write number of children.
-    ZoneGrowableArray<CodeRegionTrieNode*>& kids = children();
-    intptr_t child_count = kids.length();
-    array->AddValue(child_count);
-    // Recurse.
-    for (intptr_t i = 0; i < child_count; i++) {
-      kids[i]->PrintToJSONArray(array);
-    }
-  }
-
- private:
-  static int CodeRegionTrieNodeCompare(CodeRegionTrieNode* const* a,
-                                       CodeRegionTrieNode* const* b) {
-    ASSERT(a != NULL);
-    ASSERT(b != NULL);
-    return (*b)->count() - (*a)->count();
-  }
-
-  const intptr_t code_region_index_;
-  intptr_t count_;
-  ZoneGrowableArray<CodeRegionTrieNode*>* children_;
-};
-
-
-class CodeRegionTrieBuilder : public TrieBuilder {
- public:
-  CodeRegionTrieBuilder(Isolate* isolate,
-                        CodeRegionTable* live_code_table,
-                        CodeRegionTable* dead_code_table,
-                        CodeRegionTable* tag_code_table)
-      : TrieBuilder(live_code_table, dead_code_table, tag_code_table) {
-    set_tag_order(ProfilerService::kUserVM);
-
-    // Verify that the truncated tag exists.
-    ASSERT(tag_code_table_->FindIndex(VMTag::kTruncatedTagId) >= 0);
-
-    // Verify that the root tag exists.
-    intptr_t root_index = tag_code_table_->FindIndex(VMTag::kRootTagId);
-    ASSERT(root_index >= 0);
-    CodeRegion* region = tag_code_table_->At(root_index);
-    ASSERT(region != NULL);
-
-    exclusive_root_ = new CodeRegionTrieNode(region->code_table_index());
-    inclusive_root_ = new CodeRegionTrieNode(region->code_table_index());
-  }
-
-  void Build(ProcessedSampleBuffer* buffer) {
-    for (intptr_t i = 0; i < buffer->length(); i++) {
-      ProcessedSample* sample = buffer->At(i);
-      VisitSample(sample);
-    }
-  }
-
-  CodeRegionTrieNode* inclusive_root() const {
-    return inclusive_root_;
-  }
-
-  CodeRegionTrieNode* exclusive_root() const {
-    return exclusive_root_;
-  }
-
- private:
-  void VisitSample(ProcessedSample* sample) {
-    ProcessSampleExclusive(sample);
-    ProcessSampleInclusive(sample);
-  }
-
-  void ProcessSampleInclusive(ProcessedSample* sample) {
-    // Give the root a tick.
-    inclusive_root_->Tick();
-    CodeRegionTrieNode* current = inclusive_root_;
-    current = AppendTags(sample, current);
-    if (sample->truncated()) {
-      current = AppendTruncatedTag(current);
-    }
-    // Walk the sampled PCs.
-    for (intptr_t i = sample->length() - 1; i >= 0; i--) {
-      ASSERT(sample->At(i) != 0);
-      intptr_t index = FindFinalIndex(sample->At(i), sample->timestamp());
-      if (index < 0) {
-        continue;
-      }
-      current = current->GetChild(index);
-      current->Tick();
-    }
-  }
-
-  void ProcessSampleExclusive(ProcessedSample* sample) {
-    // Give the root a tick.
-    exclusive_root_->Tick();
-    CodeRegionTrieNode* current = exclusive_root_;
-    current = AppendTags(sample, current);
-    // Walk the sampled PCs.
-    for (intptr_t i = 0; i < sample->length(); i++) {
-      ASSERT(sample->At(i) != 0);
-      intptr_t index = FindFinalIndex(sample->At(i), sample->timestamp());
-      if (index < 0) {
-        continue;
-      }
-      current = current->GetChild(index);
-      if (i == 0) {
-        // Executing PC.
-        if (!sample->first_frame_executing() || vm_tags_emitted()) {
-          // Only tick if this isn't an exit frame or VM tags are emitted.
-          current->Tick();
-        }
-      } else {
-        // Caller PCs.
-        current->Tick();
-      }
-    }
-    if (sample->truncated()) {
-      current = AppendTruncatedTag(current);
-    }
-  }
-
-  CodeRegionTrieNode* AppendUserTag(ProcessedSample* sample,
-                                    CodeRegionTrieNode* current) {
-    intptr_t user_tag_index = FindTagIndex(sample->user_tag());
-    if (user_tag_index >= 0) {
-      current = current->GetChild(user_tag_index);
+      intptr_t tag_index = GetProfileCodeTagIndex(vm_tag);
+      current = current->GetChild(tag_index);
       // Give the tag a tick.
       current->Tick();
     }
     return current;
   }
 
-  CodeRegionTrieNode* AppendTruncatedTag(CodeRegionTrieNode* current) {
-    intptr_t truncated_tag_index = FindTagIndex(VMTag::kTruncatedTagId);
+  ProfileCodeTrieNode* AppendSpecificNativeRuntimeEntryVMTag(
+      uword vm_tag, ProfileCodeTrieNode* current) {
+    // Only Native and Runtime entries have a second VM tag.
+    if (!VMTag::IsNativeEntryTag(vm_tag) &&
+        !VMTag::IsRuntimeEntryTag(vm_tag)) {
+      return current;
+    }
+    intptr_t tag_index = GetProfileCodeTagIndex(vm_tag);
+    current = current->GetChild(tag_index);
+    // Give the tag a tick.
+    current->Tick();
+    return current;
+  }
+
+  ProfileCodeTrieNode* AppendVMTags(uword vm_tag,
+                                    ProfileCodeTrieNode* current) {
+    current = AppendVMTag(vm_tag, current);
+    current = AppendSpecificNativeRuntimeEntryVMTag(vm_tag, current);
+    return current;
+  }
+
+  ProfileCodeTrieNode* AppendTags(uword vm_tag,
+                                  uword user_tag,
+                                  ProfileCodeTrieNode* current) {
+    // None.
+    if (tag_order() == Profile::kNoTags) {
+      return current;
+    }
+    // User first.
+    if ((tag_order() == Profile::kUserVM) ||
+        (tag_order() == Profile::kUser)) {
+      current = AppendUserTag(user_tag, current);
+      // Only user.
+      if (tag_order() == Profile::kUser) {
+        return current;
+      }
+      return AppendVMTags(vm_tag, current);
+    }
+    // VM first.
+    ASSERT((tag_order() == Profile::kVMUser) ||
+           (tag_order() == Profile::kVM));
+    current = AppendVMTags(vm_tag, current);
+    // Only VM.
+    if (tag_order() == Profile::kVM) {
+      return current;
+    }
+    return AppendUserTag(user_tag, current);
+  }
+
+  // ProfileFunctionTrieNode
+  ProfileFunctionTrieNode* AppendUserTag(uword user_tag,
+                                         ProfileFunctionTrieNode* current) {
+    intptr_t user_tag_index = GetProfileFunctionTagIndex(user_tag);
+    if (user_tag_index >= 0) {
+      current = current->GetChild(user_tag_index);
+      current->Tick();
+    }
+    return current;
+  }
+
+  ProfileFunctionTrieNode* AppendTruncatedTag(
+      ProfileFunctionTrieNode* current) {
+    intptr_t truncated_tag_index =
+        GetProfileFunctionTagIndex(VMTag::kTruncatedTagId);
     ASSERT(truncated_tag_index >= 0);
     current = current->GetChild(truncated_tag_index);
     current->Tick();
     return current;
   }
 
-  CodeRegionTrieNode* AppendVMTag(ProcessedSample* sample,
-                                  CodeRegionTrieNode* current) {
-    if (VMTag::IsNativeEntryTag(sample->vm_tag())) {
+  ProfileFunctionTrieNode* AppendVMTag(uword vm_tag,
+                                   ProfileFunctionTrieNode* current) {
+    if (VMTag::IsNativeEntryTag(vm_tag)) {
       // Insert a dummy kNativeTagId node.
-      intptr_t tag_index = FindTagIndex(VMTag::kNativeTagId);
+      intptr_t tag_index = GetProfileFunctionTagIndex(VMTag::kNativeTagId);
       current = current->GetChild(tag_index);
       // Give the tag a tick.
       current->Tick();
-    } else if (VMTag::IsRuntimeEntryTag(sample->vm_tag())) {
+    } else if (VMTag::IsRuntimeEntryTag(vm_tag)) {
       // Insert a dummy kRuntimeTagId node.
-      intptr_t tag_index = FindTagIndex(VMTag::kRuntimeTagId);
+      intptr_t tag_index = GetProfileFunctionTagIndex(VMTag::kRuntimeTagId);
       current = current->GetChild(tag_index);
       // Give the tag a tick.
       current->Tick();
     } else {
-      intptr_t tag_index = FindTagIndex(sample->vm_tag());
+      intptr_t tag_index = GetProfileFunctionTagIndex(vm_tag);
       current = current->GetChild(tag_index);
       // Give the tag a tick.
       current->Tick();
     }
     return current;
   }
 
-  CodeRegionTrieNode* AppendSpecificNativeRuntimeEntryVMTag(
-      ProcessedSample* sample, CodeRegionTrieNode* current) {
+  ProfileFunctionTrieNode* AppendSpecificNativeRuntimeEntryVMTag(
+      uword vm_tag, ProfileFunctionTrieNode* current) {
     // Only Native and Runtime entries have a second VM tag.
-    if (!VMTag::IsNativeEntryTag(sample->vm_tag()) &&
-        !VMTag::IsRuntimeEntryTag(sample->vm_tag())) {
+    if (!VMTag::IsNativeEntryTag(vm_tag) &&
+        !VMTag::IsRuntimeEntryTag(vm_tag)) {
       return current;
     }
-    intptr_t tag_index = FindTagIndex(sample->vm_tag());
+    intptr_t tag_index = GetProfileFunctionTagIndex(vm_tag);
     current = current->GetChild(tag_index);
     // Give the tag a tick.
     current->Tick();
     return current;
   }
 
-  CodeRegionTrieNode* AppendVMTags(ProcessedSample* sample,
-                                   CodeRegionTrieNode* current) {
-    current = AppendVMTag(sample, current);
-    current = AppendSpecificNativeRuntimeEntryVMTag(sample, current);
+  ProfileFunctionTrieNode* AppendVMTags(uword vm_tag,
+                                    ProfileFunctionTrieNode* current) {
+    current = AppendVMTag(vm_tag, current);
+    current = AppendSpecificNativeRuntimeEntryVMTag(vm_tag, current);
     return current;
   }
 
-  CodeRegionTrieNode* AppendTags(ProcessedSample* sample,
-                                 CodeRegionTrieNode* current) {
+  ProfileFunctionTrieNode* AppendTags(uword vm_tag,
+                                      uword user_tag,
+                                      ProfileFunctionTrieNode* current) {
     // None.
-    if (tag_order() == ProfilerService::kNoTags) {
+    if (tag_order() == Profile::kNoTags) {
       return current;
     }
     // User first.
-    if ((tag_order() == ProfilerService::kUserVM) ||
-        (tag_order() == ProfilerService::kUser)) {
-      current = AppendUserTag(sample, current);
+    if ((tag_order() == Profile::kUserVM) ||
+        (tag_order() == Profile::kUser)) {
+      current = AppendUserTag(user_tag, current);
       // Only user.
-      if (tag_order() == ProfilerService::kUser) {
+      if (tag_order() == Profile::kUser) {
         return current;
       }
-      return AppendVMTags(sample, current);
+      return AppendVMTags(vm_tag, current);
     }
     // VM first.
-    ASSERT((tag_order() == ProfilerService::kVMUser) ||
-           (tag_order() == ProfilerService::kVM));
-    current = AppendVMTags(sample, current);
+    ASSERT((tag_order() == Profile::kVMUser) ||
+           (tag_order() == Profile::kVM));
+    current = AppendVMTags(vm_tag, current);
     // Only VM.
-    if (tag_order() == ProfilerService::kVM) {
+    if (tag_order() == Profile::kVM) {
       return current;
     }
-    return AppendUserTag(sample, current);
-  }
-
-  CodeRegionTrieNode* exclusive_root_;
-  CodeRegionTrieNode* inclusive_root_;
+    return AppendUserTag(user_tag, current);
+  }
+
+  intptr_t GetProfileCodeTagIndex(uword tag) {
+    ProfileCodeTable* tag_table = profile_->tag_code_;
+    intptr_t index = tag_table->FindCodeIndexForPC(tag);
+    ASSERT(index >= 0);
+    ProfileCode* code = tag_table->At(index);
+    ASSERT(code != NULL);
+    return code->code_table_index();
+  }
+
+  intptr_t GetProfileFunctionTagIndex(uword tag) {
+    ProfileCodeTable* tag_table = profile_->tag_code_;
+    intptr_t index = tag_table->FindCodeIndexForPC(tag);
+    ASSERT(index >= 0);
+    ProfileCode* code = tag_table->At(index);
+    ASSERT(code != NULL);
+    ProfileFunction* function = code->function();
+    ASSERT(function != NULL);
+    return function->table_index();
+  }
+
+  intptr_t GetProfileCodeIndex(uword pc, int64_t timestamp) {
+    return GetProfileCode(pc, timestamp)->code_table_index();
+  }
+
+  ProfileCode* GetProfileCode(uword pc, int64_t timestamp) {
+    ProfileCodeTable* live_table = profile_->live_code_;
+    ProfileCodeTable* dead_table = profile_->dead_code_;
+
+    intptr_t index = live_table->FindCodeIndexForPC(pc);
+    ProfileCode* code = NULL;
+    if (index < 0) {
+      index = dead_table->FindCodeIndexForPC(pc);
+      ASSERT(index >= 0);
+      code = dead_table->At(index);
+    } else {
+      code = live_table->At(index);
+      ASSERT(code != NULL);
+      if (code->compile_timestamp() > timestamp) {
+        // Code is newer than sample. Fall back to dead code table.
+        index = dead_table->FindCodeIndexForPC(pc);
+        ASSERT(index >= 0);
+        code = dead_table->At(index);
+      }
+    }
+
+    ASSERT(code != NULL);
+    ASSERT(code->Contains(pc));
+    ASSERT(code->compile_timestamp() <= timestamp);
+    return code;
+  }
+
+  void RegisterProfileCodeTag(uword tag) {
+    if (tag == 0) {
+      // No tag.
+      return;
+    }
+    ProfileCodeTable* tag_table = profile_->tag_code_;
+    intptr_t index = tag_table->FindCodeIndexForPC(tag);
+    if (index >= 0) {
+      // Already created.
+      return;
+    }
+    ProfileCode* code = new ProfileCode(ProfileCode::kTagCode,
+                                        tag,
+                                        tag + 1,
+                                        0,
+                                        null_code_);
+    index = tag_table->InsertCode(code);
+    ASSERT(index >= 0);
+  }
+
+  ProfileCode* CreateProfileCodeReused(uword pc) {
+    ProfileCode* code = new ProfileCode(ProfileCode::kReusedCode,
+                                        pc,
+                                        pc + 1,
+                                        0,
+                                        null_code_);
+    return code;
+  }
+
+  ProfileCode* CreateProfileCode(uword pc) {
+    const intptr_t kDartCodeAlignment = OS::PreferredCodeAlignment();
+    const intptr_t kDartCodeAlignmentMask = ~(kDartCodeAlignment - 1);
+    Code& code = Code::Handle(isolate_);
+
+    // Check current isolate for pc.
+    if (isolate_->heap()->CodeContains(pc)) {
+      code ^= Code::LookupCode(pc);
+      if (!code.IsNull()) {
+        deoptimized_code_->Add(code);
+        return new ProfileCode(ProfileCode::kDartCode,
+                              code.EntryPoint(),
+                              code.EntryPoint() + code.Size(),
+                              code.compile_timestamp(),
+                              code);
+      }
+      return new ProfileCode(ProfileCode::kCollectedCode,
+                            pc,
+                            (pc & kDartCodeAlignmentMask) + kDartCodeAlignment,
+                            0,
+                            code);
+    }
+
+    // Check VM isolate for pc.
+    if (vm_isolate_->heap()->CodeContains(pc)) {
+      code ^= Code::LookupCodeInVmIsolate(pc);
+      if (!code.IsNull()) {
+        return new ProfileCode(ProfileCode::kDartCode,
+                              code.EntryPoint(),
+                              code.EntryPoint() + code.Size(),
+                              code.compile_timestamp(),
+                              code);
+      }
+      return new ProfileCode(ProfileCode::kCollectedCode,
+                            pc,
+                            (pc & kDartCodeAlignmentMask) + kDartCodeAlignment,
+                            0,
+                            code);
+    }
+
+    // Check NativeSymbolResolver for pc.
+    uintptr_t native_start = 0;
+    char* native_name = NativeSymbolResolver::LookupSymbolName(pc,
+                                                               &native_start);
+    if (native_name == NULL) {
+      // No native name found.
+      return new ProfileCode(ProfileCode::kNativeCode,
+                            pc,
+                            pc + 1,
+                            0,
+                            code);
+    }
+    ASSERT(pc >= native_start);
+    ProfileCode* profile_code =
+        new ProfileCode(ProfileCode::kNativeCode,
+                       native_start,
+                       pc + 1,
+                       0,
+                       code);
+    profile_code->SetName(native_name);
+    free(native_name);
+    return profile_code;
+  }
+
+  ProfileCode* RegisterProfileCode(uword pc, int64_t timestamp) {
+    ProfileCodeTable* live_table = profile_->live_code_;
+    ProfileCodeTable* dead_table = profile_->dead_code_;
+
+    ProfileCode* code = live_table->FindCodeForPC(pc);
+    if (code == NULL) {
+      // Code not found.
+      intptr_t index = live_table->InsertCode(CreateProfileCode(pc));
+      ASSERT(index >= 0);
+      code = live_table->At(index);
+      if (code->compile_timestamp() <= timestamp) {
+        // Code was compiled before sample was taken.
+        return code;
+      }
+      // Code was compiled after the sample was taken. Insert code object into
+      // the dead code table.
+      index = dead_table->InsertCode(CreateProfileCodeReused(pc));
+      ASSERT(index >= 0);
+      return dead_table->At(index);
+    }
+    // Existing code found.
+    if (code->compile_timestamp() <= timestamp) {
+      // Code was compiled before sample was taken.
+      return code;
+    }
+    // Code was compiled after the sample was taken. Check if we have an entry
+    // in the dead code table.
+    code = dead_table->FindCodeForPC(pc);
+    if (code != NULL) {
+      return code;
+    }
+    // Create a new dead code entry.
+    intptr_t index = dead_table->InsertCode(CreateProfileCodeReused(pc));
+    ASSERT(index >= 0);
+    return dead_table->At(index);
+  }
+
+  Profile::TagOrder tag_order() const {
+    return tag_order_;
+  }
+
+  bool vm_tags_emitted() const {
+    return (tag_order_ == Profile::kUserVM) ||
+           (tag_order_ == Profile::kVMUser) ||
+           (tag_order_ == Profile::kVM);
+  }
+
+  Isolate* isolate_;
+  Isolate* vm_isolate_;
+  SampleFilter* filter_;
+  Profile::TagOrder tag_order_;
+  Profile* profile_;
+  DeoptimizedCodeSet* deoptimized_code_;
+  const Code& null_code_;
+  const Function& null_function_;
+  bool tick_functions_;
+
+  ProcessedSampleBuffer* samples_;
 };
 
 
+Profile::Profile(Isolate* isolate)
+    : isolate_(isolate),
+      live_code_(NULL),
+      dead_code_(NULL),
+      tag_code_(NULL),
+      functions_(NULL),
+      dead_code_index_offset_(-1),
+      tag_code_index_offset_(-1),
+      min_time_(kMaxInt64),
+      max_time_(0) {
+  ASSERT(isolate_ != NULL);
+  for (intptr_t i = 0; i < kNumTrieKinds; i++) {
+    roots_[i] = NULL;
+  }
+}
+
+
+void Profile::Build(SampleFilter* filter, TagOrder tag_order) {
+  ProfileBuilder builder(isolate_, filter, tag_order, this);
+  builder.Build();
+}
+
+
+ProfileFunction* Profile::GetFunction(intptr_t index) {
+  ASSERT(functions_ != NULL);
+  return functions_->At(index);
+}
+
+
+ProfileCode* Profile::GetCode(intptr_t index) {
+  ASSERT(live_code_ != NULL);
+  ASSERT(dead_code_ != NULL);
+  ASSERT(tag_code_ != NULL);
+  ASSERT(dead_code_index_offset_ >= 0);
+  ASSERT(tag_code_index_offset_ >= 0);
+
+  // Code indexes span three arrays.
+  //           0 ... |live_code|
+  // |live_code| ... |dead_code|
+  // |dead_code| ... |tag_code|
+
+  if (index < dead_code_index_offset_) {
+    return live_code_->At(index);
+  }
+
+  if (index < tag_code_index_offset_) {
+    index -= dead_code_index_offset_;
+    return dead_code_->At(index);
+  }
+
+  index -= tag_code_index_offset_;
+  return tag_code_->At(index);
+}
+
+
+ProfileTrieNode* Profile::GetTrieRoot(TrieKind trie_kind) {
+  return roots_[static_cast<intptr_t>(trie_kind)];
+}
+
+
+void Profile::PrintJSON(JSONStream* stream) {
+  ScopeTimer sw("Profile::PrintJSON", FLAG_trace_profiler);
+  JSONObject obj(stream);
+  obj.AddProperty("type", "_CpuProfile");
+  obj.AddProperty("samplePeriod",
+                  static_cast<intptr_t>(FLAG_profile_period));
+  obj.AddProperty("stackDepth",
+                  static_cast<intptr_t>(FLAG_profile_depth));
+  obj.AddProperty("sampleCount", sample_count());
+  obj.AddProperty("timeSpan", MicrosecondsToSeconds(GetTimeSpan()));
+  {
+    JSONArray codes(&obj, "codes");
+    for (intptr_t i = 0; i < live_code_->length(); i++) {
+      ProfileCode* code = live_code_->At(i);
+      ASSERT(code != NULL);
+      code->PrintToJSONArray(&codes);
+    }
+    for (intptr_t i = 0; i < dead_code_->length(); i++) {
+      ProfileCode* code = dead_code_->At(i);
+      ASSERT(code != NULL);
+      code->PrintToJSONArray(&codes);
+    }
+    for (intptr_t i = 0; i < tag_code_->length(); i++) {
+      ProfileCode* code = tag_code_->At(i);
+      ASSERT(code != NULL);
+      code->PrintToJSONArray(&codes);
+    }
+  }
+
+  {
+    JSONArray functions(&obj, "functions");
+    for (intptr_t i = 0; i < functions_->length(); i++) {
+      ProfileFunction* function = functions_->At(i);
+      ASSERT(function != NULL);
+      function->PrintToJSONArray(&functions);
+    }
+  }
+  {
+    JSONArray code_trie(&obj, "exclusiveCodeTrie");
+    ProfileTrieNode* root = roots_[static_cast<intptr_t>(kExclusiveCode)];
+    ASSERT(root != NULL);
+    root->PrintToJSONArray(&code_trie);
+  }
+  {
+    JSONArray code_trie(&obj, "inclusiveCodeTrie");
+    ProfileTrieNode* root = roots_[static_cast<intptr_t>(kInclusiveCode)];
+    ASSERT(root != NULL);
+    root->PrintToJSONArray(&code_trie);
+  }
+  {
+    JSONArray function_trie(&obj, "exclusiveFunctionTrie");
+    ProfileTrieNode* root = roots_[static_cast<intptr_t>(kExclusiveFunction)];
+    ASSERT(root != NULL);
+    root->PrintToJSONArray(&function_trie);
+  }
+  {
+    JSONArray function_trie(&obj, "inclusiveFunctionTrie");
+    ProfileTrieNode* root = roots_[static_cast<intptr_t>(kInclusiveFunction)];
+    ASSERT(root != NULL);
+    root->PrintToJSONArray(&function_trie);
+  }
+}
+
+
 class NoAllocationSampleFilter : public SampleFilter {
  public:
   explicit NoAllocationSampleFilter(Isolate* isolate)
       : SampleFilter(isolate) {
   }
 
   bool FilterSample(Sample* sample) {
     return !sample->is_allocation_sample();
   }
 };
 
 
-void ProfilerService::PrintJSON(JSONStream* stream, TagOrder tag_order) {
+void ProfilerService::PrintJSON(JSONStream* stream,
+                                Profile::TagOrder tag_order) {
   Isolate* isolate = Isolate::Current();
   // Disable profile interrupts while processing the buffer.
   Profiler::EndExecution(isolate);
-  MutexLocker profiler_data_lock(isolate->profiler_data_mutex());
-  IsolateProfilerData* profiler_data = isolate->profiler_data();
-  if (profiler_data == NULL) {
-    stream->PrintError(kFeatureDisabled, NULL);
-    return;
+
+  {
+    MutexLocker profiler_data_lock(isolate->profiler_data_mutex());
+    IsolateProfilerData* profiler_data = isolate->profiler_data();
+    if (profiler_data == NULL) {
+      stream->PrintError(kFeatureDisabled, NULL);
+      return;
+    }
   }
-  SampleBuffer* sample_buffer = profiler_data->sample_buffer();
-  ASSERT(sample_buffer != NULL);
-  ScopeTimer sw("ProfilerService::PrintJSON", FLAG_trace_profiler);
+
   {
     StackZone zone(isolate);
     HANDLESCOPE(isolate);
+    Profile profile(isolate);
+    NoAllocationSampleFilter filter(isolate);
+    profile.Build(&filter, tag_order);
+    profile.PrintJSON(stream);
+  }
 
-    ProcessedSampleBuffer* processed_samples = NULL;
-    {
-      ScopeTimer sw("BuildProcessedSampleBuffer", FLAG_trace_profiler);
-      NoAllocationSampleFilter filter(isolate);
-      processed_samples = sample_buffer->BuildProcessedSampleBuffer(&filter);
-    }
-
-    {
-      // Live code holds Dart, Native, and Collected CodeRegions.
-      CodeRegionTable live_code_table;
-      // Dead code holds Overwritten CodeRegions.
-      CodeRegionTable dead_code_table;
-      // Tag code holds Tag CodeRegions.
-      CodeRegionTable tag_code_table;
-      // Table holding all ProfileFunctions.
-      ProfileFunctionTable function_table;
-      // Set of deoptimized code still referenced by the profiler.
-      DeoptimizedCodeSet* deoptimized_code = new DeoptimizedCodeSet(isolate);
-
-      // Build CodeRegion tables.
-      CodeRegionTableBuilder builder(isolate,
-                                     &live_code_table,
-                                     &dead_code_table,
-                                     &tag_code_table,
-                                     deoptimized_code);
-      {
-        ScopeTimer sw("CodeRegionTableBuilder::Build", FLAG_trace_profiler);
-        builder.Build(processed_samples);
-      }
-      intptr_t samples = processed_samples->length();
-      intptr_t frames = builder.frames();
-      if (FLAG_trace_profiler) {
-        intptr_t total_live_code_objects = live_code_table.Length();
-        intptr_t total_dead_code_objects = dead_code_table.Length();
-        intptr_t total_tag_code_objects = tag_code_table.Length();
-        OS::Print(
-            "Processed %" Pd " samples with %" Pd " frames\n", samples, frames);
-        OS::Print("CodeTables: live=%" Pd " dead=%" Pd " tag=%" Pd "\n",
-                  total_live_code_objects,
-                  total_dead_code_objects,
-                  total_tag_code_objects);
-      }
-
-      if (FLAG_trace_profiler) {
-        ScopeTimer sw("CodeRegionTableVerify", FLAG_trace_profiler);
-        live_code_table.Verify();
-        dead_code_table.Verify();
-        tag_code_table.Verify();
-      }
-
-      {
-        ScopeTimer st("CodeRegionFunctionMapping", FLAG_trace_profiler);
-        CodeRegionFunctionMapper mapper(isolate, &live_code_table,
-                                                 &dead_code_table,
-                                                 &tag_code_table,
-                                                 &function_table);
-        mapper.Map();
-      }
-      if (FLAG_trace_profiler) {
-        intptr_t total_functions = function_table.Length();
-        OS::Print("FunctionTable: size=%" Pd "\n", total_functions);
-      }
-      CodeRegionTrieBuilder code_trie_builder(isolate,
-                                              &live_code_table,
-                                              &dead_code_table,
-                                              &tag_code_table);
-      code_trie_builder.set_tag_order(tag_order);
-      {
-        // Build CodeRegion trie.
-        ScopeTimer sw("CodeRegionTrieBuilder::Build", FLAG_trace_profiler);
-        code_trie_builder.Build(processed_samples);
-        code_trie_builder.exclusive_root()->SortByCount();
-        code_trie_builder.inclusive_root()->SortByCount();
-      }
-      if (FLAG_trace_profiler) {
-        OS::Print("Code Trie Root Count: E: %" Pd " I: %" Pd "\n",
-                  code_trie_builder.exclusive_root()->count(),
-                  code_trie_builder.inclusive_root()->count());
-      }
-      ProfileFunctionTrieBuilder function_trie_builder(&live_code_table,
-                                                       &dead_code_table,
-                                                       &tag_code_table,
-                                                       &function_table);
-      function_trie_builder.set_tag_order(tag_order);
-      {
-        // Build ProfileFunction trie.
-        ScopeTimer sw("ProfileFunctionTrieBuilder::Build",
-                      FLAG_trace_profiler);
-        function_trie_builder.Build(processed_samples);
-        function_trie_builder.exclusive_root()->SortByCount();
-        function_trie_builder.inclusive_root()->SortByCount();
-      }
-      if (FLAG_trace_profiler) {
-        OS::Print("Function Trie Root Count: E: %" Pd " I: %" Pd "\n",
-                  function_trie_builder.exclusive_root()->count(),
-                  function_trie_builder.inclusive_root()->count());
-      }
-      {
-        ScopeTimer sw("CpuProfileJSONStream", FLAG_trace_profiler);
-        // Serialize to JSON.
-        JSONObject obj(stream);
-        obj.AddProperty("type", "_CpuProfile");
-        obj.AddProperty("sampleCount", samples);
-        obj.AddProperty("samplePeriod",
-                        static_cast<intptr_t>(FLAG_profile_period));
-        obj.AddProperty("stackDepth",
-                        static_cast<intptr_t>(FLAG_profile_depth));
-        obj.AddProperty("timeSpan",
-                        MicrosecondsToSeconds(builder.TimeDeltaMicros()));
-        {
-          JSONArray code_trie(&obj, "exclusiveCodeTrie");
-          CodeRegionTrieNode* root = code_trie_builder.exclusive_root();
-          ASSERT(root != NULL);
-          root->PrintToJSONArray(&code_trie);
-        }
-        {
-          JSONArray code_trie(&obj, "inclusiveCodeTrie");
-          CodeRegionTrieNode* root = code_trie_builder.inclusive_root();
-          ASSERT(root != NULL);
-          root->PrintToJSONArray(&code_trie);
-        }
-        {
-          JSONArray function_trie(&obj, "exclusiveFunctionTrie");
-          ProfileFunctionTrieNode* root =
-              function_trie_builder.exclusive_root();
-          ASSERT(root != NULL);
-          root->PrintToJSONArray(&function_trie);
-        }
-        {
-          JSONArray function_trie(&obj, "inclusiveFunctionTrie");
-          ProfileFunctionTrieNode* root =
-              function_trie_builder.inclusive_root();
-          ASSERT(root != NULL);
-          root->PrintToJSONArray(&function_trie);
-        }
-        {
-          JSONArray codes(&obj, "codes");
-          for (intptr_t i = 0; i < live_code_table.Length(); i++) {
-            CodeRegion* region = live_code_table.At(i);
-            ASSERT(region != NULL);
-            region->PrintToJSONArray(&codes);
-          }
-          for (intptr_t i = 0; i < dead_code_table.Length(); i++) {
-            CodeRegion* region = dead_code_table.At(i);
-            ASSERT(region != NULL);
-            region->PrintToJSONArray(&codes);
-          }
-          for (intptr_t i = 0; i < tag_code_table.Length(); i++) {
-            CodeRegion* region = tag_code_table.At(i);
-            ASSERT(region != NULL);
-            region->PrintToJSONArray(&codes);
-          }
-        }
-        {
-          JSONArray functions(&obj, "functions");
-          for (intptr_t i = 0; i < function_table.Length(); i++) {
-            ProfileFunction* function = function_table.At(i);
-            ASSERT(function != NULL);
-            function->PrintToJSONArray(&functions);
-          }
-        }
-      }
-      // Update the isolates set of dead code.
-      deoptimized_code->UpdateIsolate(isolate);
-    }
-  }
   // Enable profile interrupts.
   Profiler::BeginExecution(isolate);
 }
 
 
 void ProfilerService::ClearSamples() {
   Isolate* isolate = Isolate::Current();
 
   // Disable profile interrupts while processing the buffer.
   Profiler::EndExecution(isolate);
 
   MutexLocker profiler_data_lock(isolate->profiler_data_mutex());
   IsolateProfilerData* profiler_data = isolate->profiler_data();
   if (profiler_data == NULL) {
     return;
   }
   SampleBuffer* sample_buffer = profiler_data->sample_buffer();
   ASSERT(sample_buffer != NULL);
 
   ClearProfileVisitor clear_profile(isolate);
   sample_buffer->VisitSamples(&clear_profile);
 
   // Enable profile interrupts.
   Profiler::BeginExecution(isolate);
 }
 
 }  // namespace dart