root/src/type-info.cc

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DEFINITIONS

This source file includes following definitions.
  1. TypeFromValue
  2. GetInfo
  3. LoadIsUninitialized
  4. LoadIsMonomorphicNormal
  5. LoadIsMegamorphicWithTypeInfo
  6. StoreIsMonomorphicNormal
  7. StoreIsMegamorphicWithTypeInfo
  8. CallIsMonomorphic
  9. CallNewIsMonomorphic
  10. ObjectLiteralStoreIsMonomorphic
  11. IsForInFastCase
  12. LoadMonomorphicReceiverType
  13. StoreMonomorphicReceiverType
  14. LoadReceiverTypes
  15. StoreReceiverTypes
  16. CallReceiverTypes
  17. GetCallCheckType
  18. GetPrototypeForPrimitiveCheck
  19. GetCallTarget
  20. GetCallNewTarget
  21. GetObjectLiteralStoreMap
  22. LoadIsBuiltin
  23. CompareType
  24. IsSymbolCompare
  25. GetCompareMap
  26. UnaryType
  27. BinaryType
  28. SwitchType
  29. IncrementType
  30. CollectReceiverTypes
  31. CanRetainOtherContext
  32. CanRetainOtherContext
  33. AddMapIfMissing
  34. CollectKeyedReceiverTypes
  35. ToBooleanTypes
  36. BuildDictionary
  37. GetRelocInfos
  38. CreateDictionary
  39. RelocateRelocInfos
  40. ProcessRelocInfos
  41. ProcessTypeFeedbackCells
  42. SetInfo

// Copyright 2012 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
//       copyright notice, this list of conditions and the following
//       disclaimer in the documentation and/or other materials provided
//       with the distribution.
//     * Neither the name of Google Inc. nor the names of its
//       contributors may be used to endorse or promote products derived
//       from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#include "v8.h"

#include "ast.h"
#include "code-stubs.h"
#include "compiler.h"
#include "ic.h"
#include "macro-assembler.h"
#include "stub-cache.h"
#include "type-info.h"

#include "ic-inl.h"
#include "objects-inl.h"

namespace v8 {
namespace internal {


TypeInfo TypeInfo::TypeFromValue(Handle<Object> value) {
  TypeInfo info;
  if (value->IsSmi()) {
    info = TypeInfo::Smi();
  } else if (value->IsHeapNumber()) {
    info = TypeInfo::IsInt32Double(HeapNumber::cast(*value)->value())
        ? TypeInfo::Integer32()
        : TypeInfo::Double();
  } else if (value->IsString()) {
    info = TypeInfo::String();
  } else {
    info = TypeInfo::Unknown();
  }
  return info;
}


TypeFeedbackOracle::TypeFeedbackOracle(Handle<Code> code,
                                       Handle<Context> global_context,
                                       Isolate* isolate,
                                       Zone* zone) {
  global_context_ = global_context;
  isolate_ = isolate;
  zone_ = zone;
  BuildDictionary(code);
  ASSERT(reinterpret_cast<Address>(*dictionary_.location()) != kHandleZapValue);
}


Handle<Object> TypeFeedbackOracle::GetInfo(unsigned ast_id) {
  int entry = dictionary_->FindEntry(ast_id);
  return entry != UnseededNumberDictionary::kNotFound
      ? Handle<Object>(dictionary_->ValueAt(entry))
      : Handle<Object>::cast(isolate_->factory()->undefined_value());
}


bool TypeFeedbackOracle::LoadIsUninitialized(Property* expr) {
  Handle<Object> map_or_code = GetInfo(expr->id());
  if (map_or_code->IsMap()) return false;
  if (map_or_code->IsCode()) {
    Handle<Code> code = Handle<Code>::cast(map_or_code);
    return code->is_inline_cache_stub() && code->ic_state() == UNINITIALIZED;
  }
  return false;
}


bool TypeFeedbackOracle::LoadIsMonomorphicNormal(Property* expr) {
  Handle<Object> map_or_code = GetInfo(expr->id());
  if (map_or_code->IsMap()) return true;
  if (map_or_code->IsCode()) {
    Handle<Code> code = Handle<Code>::cast(map_or_code);
    return code->is_keyed_load_stub() &&
        code->ic_state() == MONOMORPHIC &&
        Code::ExtractTypeFromFlags(code->flags()) == Code::NORMAL &&
        code->FindFirstMap() != NULL &&
        !CanRetainOtherContext(code->FindFirstMap(), *global_context_);
  }
  return false;
}


bool TypeFeedbackOracle::LoadIsMegamorphicWithTypeInfo(Property* expr) {
  Handle<Object> map_or_code = GetInfo(expr->id());
  if (map_or_code->IsCode()) {
    Handle<Code> code = Handle<Code>::cast(map_or_code);
    Builtins* builtins = isolate_->builtins();
    return code->is_keyed_load_stub() &&
        *code != builtins->builtin(Builtins::kKeyedLoadIC_Generic) &&
        code->ic_state() == MEGAMORPHIC;
  }
  return false;
}


bool TypeFeedbackOracle::StoreIsMonomorphicNormal(Expression* expr) {
  Handle<Object> map_or_code = GetInfo(expr->id());
  if (map_or_code->IsMap()) return true;
  if (map_or_code->IsCode()) {
    Handle<Code> code = Handle<Code>::cast(map_or_code);
    bool allow_growth =
        Code::GetKeyedAccessGrowMode(code->extra_ic_state()) ==
        ALLOW_JSARRAY_GROWTH;
    return code->is_keyed_store_stub() &&
        !allow_growth &&
        code->ic_state() == MONOMORPHIC &&
        Code::ExtractTypeFromFlags(code->flags()) == Code::NORMAL &&
        code->FindFirstMap() != NULL &&
        !CanRetainOtherContext(code->FindFirstMap(), *global_context_);
  }
  return false;
}


bool TypeFeedbackOracle::StoreIsMegamorphicWithTypeInfo(Expression* expr) {
  Handle<Object> map_or_code = GetInfo(expr->id());
  if (map_or_code->IsCode()) {
    Handle<Code> code = Handle<Code>::cast(map_or_code);
    Builtins* builtins = isolate_->builtins();
    bool allow_growth =
        Code::GetKeyedAccessGrowMode(code->extra_ic_state()) ==
        ALLOW_JSARRAY_GROWTH;
    return code->is_keyed_store_stub() &&
        !allow_growth &&
        *code != builtins->builtin(Builtins::kKeyedStoreIC_Generic) &&
        *code != builtins->builtin(Builtins::kKeyedStoreIC_Generic_Strict) &&
        code->ic_state() == MEGAMORPHIC;
  }
  return false;
}


bool TypeFeedbackOracle::CallIsMonomorphic(Call* expr) {
  Handle<Object> value = GetInfo(expr->id());
  return value->IsMap() || value->IsSmi() || value->IsJSFunction();
}


bool TypeFeedbackOracle::CallNewIsMonomorphic(CallNew* expr) {
  Handle<Object> value = GetInfo(expr->id());
  return value->IsJSFunction();
}


bool TypeFeedbackOracle::ObjectLiteralStoreIsMonomorphic(
    ObjectLiteral::Property* prop) {
  Handle<Object> map_or_code = GetInfo(prop->key()->id());
  return map_or_code->IsMap();
}


bool TypeFeedbackOracle::IsForInFastCase(ForInStatement* stmt) {
  Handle<Object> value = GetInfo(stmt->PrepareId());
  return value->IsSmi() &&
      Smi::cast(*value)->value() == TypeFeedbackCells::kForInFastCaseMarker;
}


Handle<Map> TypeFeedbackOracle::LoadMonomorphicReceiverType(Property* expr) {
  ASSERT(LoadIsMonomorphicNormal(expr));
  Handle<Object> map_or_code = GetInfo(expr->id());
  if (map_or_code->IsCode()) {
    Handle<Code> code = Handle<Code>::cast(map_or_code);
    Map* first_map = code->FindFirstMap();
    ASSERT(first_map != NULL);
    return CanRetainOtherContext(first_map, *global_context_)
        ? Handle<Map>::null()
        : Handle<Map>(first_map);
  }
  return Handle<Map>::cast(map_or_code);
}


Handle<Map> TypeFeedbackOracle::StoreMonomorphicReceiverType(Expression* expr) {
  ASSERT(StoreIsMonomorphicNormal(expr));
  Handle<Object> map_or_code = GetInfo(expr->id());
  if (map_or_code->IsCode()) {
    Handle<Code> code = Handle<Code>::cast(map_or_code);
    Map* first_map = code->FindFirstMap();
    ASSERT(first_map != NULL);
    return CanRetainOtherContext(first_map, *global_context_)
        ? Handle<Map>::null()
        : Handle<Map>(first_map);
  }
  return Handle<Map>::cast(map_or_code);
}


void TypeFeedbackOracle::LoadReceiverTypes(Property* expr,
                                           Handle<String> name,
                                           SmallMapList* types) {
  Code::Flags flags =
      Code::ComputeMonomorphicFlags(Code::LOAD_IC, Code::NORMAL);
  CollectReceiverTypes(expr->id(), name, flags, types);
}


void TypeFeedbackOracle::StoreReceiverTypes(Assignment* expr,
                                            Handle<String> name,
                                            SmallMapList* types) {
  Code::Flags flags =
      Code::ComputeMonomorphicFlags(Code::STORE_IC, Code::NORMAL);
  CollectReceiverTypes(expr->id(), name, flags, types);
}


void TypeFeedbackOracle::CallReceiverTypes(Call* expr,
                                           Handle<String> name,
                                           CallKind call_kind,
                                           SmallMapList* types) {
  int arity = expr->arguments()->length();

  // Note: Currently we do not take string extra ic data into account
  // here.
  Code::ExtraICState extra_ic_state =
      CallIC::Contextual::encode(call_kind == CALL_AS_FUNCTION);

  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::CALL_IC,
                                                    Code::NORMAL,
                                                    extra_ic_state,
                                                    OWN_MAP,
                                                    arity);
  CollectReceiverTypes(expr->id(), name, flags, types);
}


CheckType TypeFeedbackOracle::GetCallCheckType(Call* expr) {
  Handle<Object> value = GetInfo(expr->id());
  if (!value->IsSmi()) return RECEIVER_MAP_CHECK;
  CheckType check = static_cast<CheckType>(Smi::cast(*value)->value());
  ASSERT(check != RECEIVER_MAP_CHECK);
  return check;
}


Handle<JSObject> TypeFeedbackOracle::GetPrototypeForPrimitiveCheck(
    CheckType check) {
  JSFunction* function = NULL;
  switch (check) {
    case RECEIVER_MAP_CHECK:
      UNREACHABLE();
      break;
    case STRING_CHECK:
      function = global_context_->string_function();
      break;
    case NUMBER_CHECK:
      function = global_context_->number_function();
      break;
    case BOOLEAN_CHECK:
      function = global_context_->boolean_function();
      break;
  }
  ASSERT(function != NULL);
  return Handle<JSObject>(JSObject::cast(function->instance_prototype()));
}


Handle<JSFunction> TypeFeedbackOracle::GetCallTarget(Call* expr) {
  return Handle<JSFunction>::cast(GetInfo(expr->id()));
}


Handle<JSFunction> TypeFeedbackOracle::GetCallNewTarget(CallNew* expr) {
  return Handle<JSFunction>::cast(GetInfo(expr->id()));
}


Handle<Map> TypeFeedbackOracle::GetObjectLiteralStoreMap(
    ObjectLiteral::Property* prop) {
  ASSERT(ObjectLiteralStoreIsMonomorphic(prop));
  return Handle<Map>::cast(GetInfo(prop->key()->id()));
}


bool TypeFeedbackOracle::LoadIsBuiltin(Property* expr, Builtins::Name id) {
  return *GetInfo(expr->id()) ==
      isolate_->builtins()->builtin(id);
}


TypeInfo TypeFeedbackOracle::CompareType(CompareOperation* expr) {
  Handle<Object> object = GetInfo(expr->id());
  TypeInfo unknown = TypeInfo::Unknown();
  if (!object->IsCode()) return unknown;
  Handle<Code> code = Handle<Code>::cast(object);
  if (!code->is_compare_ic_stub()) return unknown;

  CompareIC::State state = static_cast<CompareIC::State>(code->compare_state());
  switch (state) {
    case CompareIC::UNINITIALIZED:
      // Uninitialized means never executed.
      return TypeInfo::Uninitialized();
    case CompareIC::SMIS:
      return TypeInfo::Smi();
    case CompareIC::HEAP_NUMBERS:
      return TypeInfo::Number();
    case CompareIC::SYMBOLS:
    case CompareIC::STRINGS:
      return TypeInfo::String();
    case CompareIC::OBJECTS:
    case CompareIC::KNOWN_OBJECTS:
      // TODO(kasperl): We really need a type for JS objects here.
      return TypeInfo::NonPrimitive();
    case CompareIC::GENERIC:
    default:
      return unknown;
  }
}


bool TypeFeedbackOracle::IsSymbolCompare(CompareOperation* expr) {
  Handle<Object> object = GetInfo(expr->id());
  if (!object->IsCode()) return false;
  Handle<Code> code = Handle<Code>::cast(object);
  if (!code->is_compare_ic_stub()) return false;
  CompareIC::State state = static_cast<CompareIC::State>(code->compare_state());
  return state == CompareIC::SYMBOLS;
}


Handle<Map> TypeFeedbackOracle::GetCompareMap(CompareOperation* expr) {
  Handle<Object> object = GetInfo(expr->id());
  if (!object->IsCode()) return Handle<Map>::null();
  Handle<Code> code = Handle<Code>::cast(object);
  if (!code->is_compare_ic_stub()) return Handle<Map>::null();
  CompareIC::State state = static_cast<CompareIC::State>(code->compare_state());
  if (state != CompareIC::KNOWN_OBJECTS) {
    return Handle<Map>::null();
  }
  Map* first_map = code->FindFirstMap();
  ASSERT(first_map != NULL);
  return CanRetainOtherContext(first_map, *global_context_)
      ? Handle<Map>::null()
      : Handle<Map>(first_map);
}


TypeInfo TypeFeedbackOracle::UnaryType(UnaryOperation* expr) {
  Handle<Object> object = GetInfo(expr->id());
  TypeInfo unknown = TypeInfo::Unknown();
  if (!object->IsCode()) return unknown;
  Handle<Code> code = Handle<Code>::cast(object);
  ASSERT(code->is_unary_op_stub());
  UnaryOpIC::TypeInfo type = static_cast<UnaryOpIC::TypeInfo>(
      code->unary_op_type());
  switch (type) {
    case UnaryOpIC::SMI:
      return TypeInfo::Smi();
    case UnaryOpIC::HEAP_NUMBER:
      return TypeInfo::Double();
    default:
      return unknown;
  }
}


TypeInfo TypeFeedbackOracle::BinaryType(BinaryOperation* expr) {
  Handle<Object> object = GetInfo(expr->id());
  TypeInfo unknown = TypeInfo::Unknown();
  if (!object->IsCode()) return unknown;
  Handle<Code> code = Handle<Code>::cast(object);
  if (code->is_binary_op_stub()) {
    BinaryOpIC::TypeInfo type = static_cast<BinaryOpIC::TypeInfo>(
        code->binary_op_type());
    BinaryOpIC::TypeInfo result_type = static_cast<BinaryOpIC::TypeInfo>(
        code->binary_op_result_type());

    switch (type) {
      case BinaryOpIC::UNINITIALIZED:
        // Uninitialized means never executed.
        return TypeInfo::Uninitialized();
      case BinaryOpIC::SMI:
        switch (result_type) {
          case BinaryOpIC::UNINITIALIZED:
            if (expr->op() == Token::DIV) {
              return TypeInfo::Double();
            }
            return TypeInfo::Smi();
          case BinaryOpIC::SMI:
            return TypeInfo::Smi();
          case BinaryOpIC::INT32:
            return TypeInfo::Integer32();
          case BinaryOpIC::HEAP_NUMBER:
            return TypeInfo::Double();
          default:
            return unknown;
        }
      case BinaryOpIC::INT32:
        if (expr->op() == Token::DIV ||
            result_type == BinaryOpIC::HEAP_NUMBER) {
          return TypeInfo::Double();
        }
        return TypeInfo::Integer32();
      case BinaryOpIC::HEAP_NUMBER:
        return TypeInfo::Double();
      case BinaryOpIC::BOTH_STRING:
        return TypeInfo::String();
      case BinaryOpIC::STRING:
      case BinaryOpIC::GENERIC:
        return unknown;
     default:
        return unknown;
    }
  }
  return unknown;
}


TypeInfo TypeFeedbackOracle::SwitchType(CaseClause* clause) {
  Handle<Object> object = GetInfo(clause->CompareId());
  TypeInfo unknown = TypeInfo::Unknown();
  if (!object->IsCode()) return unknown;
  Handle<Code> code = Handle<Code>::cast(object);
  if (!code->is_compare_ic_stub()) return unknown;

  CompareIC::State state = static_cast<CompareIC::State>(code->compare_state());
  switch (state) {
    case CompareIC::UNINITIALIZED:
      // Uninitialized means never executed.
      // TODO(fschneider): Introduce a separate value for never-executed ICs.
      return unknown;
    case CompareIC::SMIS:
      return TypeInfo::Smi();
    case CompareIC::STRINGS:
      return TypeInfo::String();
    case CompareIC::SYMBOLS:
      return TypeInfo::Symbol();
    case CompareIC::HEAP_NUMBERS:
      return TypeInfo::Number();
    case CompareIC::OBJECTS:
    case CompareIC::KNOWN_OBJECTS:
      // TODO(kasperl): We really need a type for JS objects here.
      return TypeInfo::NonPrimitive();
    case CompareIC::GENERIC:
    default:
      return unknown;
  }
}


TypeInfo TypeFeedbackOracle::IncrementType(CountOperation* expr) {
  Handle<Object> object = GetInfo(expr->CountId());
  TypeInfo unknown = TypeInfo::Unknown();
  if (!object->IsCode()) return unknown;
  Handle<Code> code = Handle<Code>::cast(object);
  if (!code->is_binary_op_stub()) return unknown;

  BinaryOpIC::TypeInfo type = static_cast<BinaryOpIC::TypeInfo>(
      code->binary_op_type());
  switch (type) {
    case BinaryOpIC::UNINITIALIZED:
    case BinaryOpIC::SMI:
      return TypeInfo::Smi();
    case BinaryOpIC::INT32:
      return TypeInfo::Integer32();
    case BinaryOpIC::HEAP_NUMBER:
      return TypeInfo::Double();
    case BinaryOpIC::BOTH_STRING:
    case BinaryOpIC::STRING:
    case BinaryOpIC::GENERIC:
      return unknown;
    default:
      return unknown;
  }
  UNREACHABLE();
  return unknown;
}


void TypeFeedbackOracle::CollectReceiverTypes(unsigned ast_id,
                                              Handle<String> name,
                                              Code::Flags flags,
                                              SmallMapList* types) {
  Handle<Object> object = GetInfo(ast_id);
  if (object->IsUndefined() || object->IsSmi()) return;

  if (*object ==
      isolate_->builtins()->builtin(Builtins::kStoreIC_GlobalProxy)) {
    // TODO(fschneider): We could collect the maps and signal that
    // we need a generic store (or load) here.
    ASSERT(Handle<Code>::cast(object)->ic_state() == MEGAMORPHIC);
  } else if (object->IsMap()) {
    types->Add(Handle<Map>::cast(object), zone());
  } else if (FLAG_collect_megamorphic_maps_from_stub_cache &&
      Handle<Code>::cast(object)->ic_state() == MEGAMORPHIC) {
    types->Reserve(4, zone());
    ASSERT(object->IsCode());
    isolate_->stub_cache()->CollectMatchingMaps(types,
                                                *name,
                                                flags,
                                                global_context_,
                                                zone());
  }
}


// Check if a map originates from a given global context. We use this
// information to filter out maps from different context to avoid
// retaining objects from different tabs in Chrome via optimized code.
bool TypeFeedbackOracle::CanRetainOtherContext(Map* map,
                                               Context* global_context) {
  Object* constructor = NULL;
  while (!map->prototype()->IsNull()) {
    constructor = map->constructor();
    if (!constructor->IsNull()) {
      // If the constructor is not null or a JSFunction, we have to
      // conservatively assume that it may retain a global context.
      if (!constructor->IsJSFunction()) return true;
      // Check if the constructor directly references a foreign context.
      if (CanRetainOtherContext(JSFunction::cast(constructor),
                                global_context)) {
        return true;
      }
    }
    map = HeapObject::cast(map->prototype())->map();
  }
  constructor = map->constructor();
  if (constructor->IsNull()) return false;
  JSFunction* function = JSFunction::cast(constructor);
  return CanRetainOtherContext(function, global_context);
}


bool TypeFeedbackOracle::CanRetainOtherContext(JSFunction* function,
                                               Context* global_context) {
  return function->context()->global() != global_context->global()
      && function->context()->global() != global_context->builtins();
}


static void AddMapIfMissing(Handle<Map> map, SmallMapList* list,
                            Zone* zone) {
  for (int i = 0; i < list->length(); ++i) {
    if (list->at(i).is_identical_to(map)) return;
  }
  list->Add(map, zone);
}


void TypeFeedbackOracle::CollectKeyedReceiverTypes(unsigned ast_id,
                                                   SmallMapList* types) {
  Handle<Object> object = GetInfo(ast_id);
  if (!object->IsCode()) return;
  Handle<Code> code = Handle<Code>::cast(object);
  if (code->kind() == Code::KEYED_LOAD_IC ||
      code->kind() == Code::KEYED_STORE_IC) {
    AssertNoAllocation no_allocation;
    int mask = RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT);
    for (RelocIterator it(*code, mask); !it.done(); it.next()) {
      RelocInfo* info = it.rinfo();
      Object* object = info->target_object();
      if (object->IsMap()) {
        Map* map = Map::cast(object);
        if (!CanRetainOtherContext(map, *global_context_)) {
          AddMapIfMissing(Handle<Map>(map), types, zone());
        }
      }
    }
  }
}


byte TypeFeedbackOracle::ToBooleanTypes(unsigned ast_id) {
  Handle<Object> object = GetInfo(ast_id);
  return object->IsCode() ? Handle<Code>::cast(object)->to_boolean_state() : 0;
}


// Things are a bit tricky here: The iterator for the RelocInfos and the infos
// themselves are not GC-safe, so we first get all infos, then we create the
// dictionary (possibly triggering GC), and finally we relocate the collected
// infos before we process them.
void TypeFeedbackOracle::BuildDictionary(Handle<Code> code) {
  AssertNoAllocation no_allocation;
  ZoneList<RelocInfo> infos(16, zone());
  HandleScope scope;
  GetRelocInfos(code, &infos);
  CreateDictionary(code, &infos);
  ProcessRelocInfos(&infos);
  ProcessTypeFeedbackCells(code);
  // Allocate handle in the parent scope.
  dictionary_ = scope.CloseAndEscape(dictionary_);
}


void TypeFeedbackOracle::GetRelocInfos(Handle<Code> code,
                                       ZoneList<RelocInfo>* infos) {
  int mask = RelocInfo::ModeMask(RelocInfo::CODE_TARGET_WITH_ID);
  for (RelocIterator it(*code, mask); !it.done(); it.next()) {
    infos->Add(*it.rinfo(), zone());
  }
}


void TypeFeedbackOracle::CreateDictionary(Handle<Code> code,
                                          ZoneList<RelocInfo>* infos) {
  DisableAssertNoAllocation allocation_allowed;
  int cell_count = code->type_feedback_info()->IsTypeFeedbackInfo()
      ? TypeFeedbackInfo::cast(code->type_feedback_info())->
          type_feedback_cells()->CellCount()
      : 0;
  int length = infos->length() + cell_count;
  byte* old_start = code->instruction_start();
  dictionary_ = FACTORY->NewUnseededNumberDictionary(length);
  byte* new_start = code->instruction_start();
  RelocateRelocInfos(infos, old_start, new_start);
}


void TypeFeedbackOracle::RelocateRelocInfos(ZoneList<RelocInfo>* infos,
                                            byte* old_start,
                                            byte* new_start) {
  for (int i = 0; i < infos->length(); i++) {
    RelocInfo* info = &(*infos)[i];
    info->set_pc(new_start + (info->pc() - old_start));
  }
}


void TypeFeedbackOracle::ProcessRelocInfos(ZoneList<RelocInfo>* infos) {
  for (int i = 0; i < infos->length(); i++) {
    RelocInfo reloc_entry = (*infos)[i];
    Address target_address = reloc_entry.target_address();
    unsigned ast_id = static_cast<unsigned>((*infos)[i].data());
    Code* target = Code::GetCodeFromTargetAddress(target_address);
    switch (target->kind()) {
      case Code::LOAD_IC:
      case Code::STORE_IC:
      case Code::CALL_IC:
      case Code::KEYED_CALL_IC:
        if (target->ic_state() == MONOMORPHIC) {
          if (target->kind() == Code::CALL_IC &&
              target->check_type() != RECEIVER_MAP_CHECK) {
            SetInfo(ast_id, Smi::FromInt(target->check_type()));
          } else {
            Object* map = target->FindFirstMap();
            if (map == NULL) {
              SetInfo(ast_id, static_cast<Object*>(target));
            } else if (!CanRetainOtherContext(Map::cast(map),
                                              *global_context_)) {
              SetInfo(ast_id, map);
            }
          }
        } else {
          SetInfo(ast_id, target);
        }
        break;

      case Code::KEYED_LOAD_IC:
      case Code::KEYED_STORE_IC:
        if (target->ic_state() == MONOMORPHIC ||
            target->ic_state() == MEGAMORPHIC) {
          SetInfo(ast_id, target);
        }
        break;

      case Code::UNARY_OP_IC:
      case Code::BINARY_OP_IC:
      case Code::COMPARE_IC:
      case Code::TO_BOOLEAN_IC:
        SetInfo(ast_id, target);
        break;

      default:
        break;
    }
  }
}


void TypeFeedbackOracle::ProcessTypeFeedbackCells(Handle<Code> code) {
  Object* raw_info = code->type_feedback_info();
  if (!raw_info->IsTypeFeedbackInfo()) return;
  Handle<TypeFeedbackCells> cache(
      TypeFeedbackInfo::cast(raw_info)->type_feedback_cells());
  for (int i = 0; i < cache->CellCount(); i++) {
    unsigned ast_id = cache->AstId(i)->value();
    Object* value = cache->Cell(i)->value();
    if (value->IsSmi() ||
        (value->IsJSFunction() &&
         !CanRetainOtherContext(JSFunction::cast(value),
                                *global_context_))) {
      SetInfo(ast_id, value);
    }
  }
}


void TypeFeedbackOracle::SetInfo(unsigned ast_id, Object* target) {
  ASSERT(dictionary_->FindEntry(ast_id) == UnseededNumberDictionary::kNotFound);
  MaybeObject* maybe_result = dictionary_->AtNumberPut(ast_id, target);
  USE(maybe_result);
#ifdef DEBUG
  Object* result = NULL;
  // Dictionary has been allocated with sufficient size for all elements.
  ASSERT(maybe_result->ToObject(&result));
  ASSERT(*dictionary_ == result);
#endif
}

} }  // namespace v8::internal

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