v8/src/stub-cache.cc

// Copyright 2006-2008 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
//       copyright notice, this list of conditions and the following
//       disclaimer in the documentation and/or other materials provided
//       with the distribution.
//     * Neither the name of Google Inc. nor the names of its
//       contributors may be used to endorse or promote products derived
//       from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#include "v8.h"

#include "api.h"
#include "arguments.h"
#include "ic-inl.h"
#include "stub-cache.h"

namespace v8 { namespace internal {

// -----------------------------------------------------------------------
// StubCache implementation.


StubCache::Entry StubCache::primary_[StubCache::kPrimaryTableSize];
StubCache::Entry StubCache::secondary_[StubCache::kSecondaryTableSize];

void StubCache::Initialize(bool create_heap_objects) {
  ASSERT(IsPowerOf2(kPrimaryTableSize));
  ASSERT(IsPowerOf2(kSecondaryTableSize));
  if (create_heap_objects) {
    HandleScope scope;
    Clear();
  }
}


Code* StubCache::Set(String* name, Map* map, Code* code) {
  // Get the flags from the code.
  Code::Flags flags = Code::RemoveTypeFromFlags(code->flags());

  // Validate that the name does not move on scavenge, and that we
  // can use identity checks instead of string equality checks.
  ASSERT(!Heap::InNewSpace(name));
  ASSERT(name->IsSymbol());

  // The state bits are not important to the hash function because
  // the stub cache only contains monomorphic stubs. Make sure that
  // the bits are the least significant so they will be the ones
  // masked out.
  ASSERT(Code::ExtractICStateFromFlags(flags) == MONOMORPHIC);
  ASSERT(Code::kFlagsICStateShift == 0);

  // Make sure that the code type is not included in the hash.
  ASSERT(Code::ExtractTypeFromFlags(flags) == 0);

  // Compute the primary entry.
  int primary_offset = PrimaryOffset(name, flags, map);
  Entry* primary = entry(primary_, primary_offset);
  Code* hit = primary->value;

  // If the primary entry has useful data in it, we retire it to the
  // secondary cache before overwriting it.
  if (hit != Builtins::builtin(Builtins::Illegal)) {
    Code::Flags primary_flags = Code::RemoveTypeFromFlags(hit->flags());
    int secondary_offset =
        SecondaryOffset(primary->key, primary_flags, primary_offset);
    Entry* secondary = entry(secondary_, secondary_offset);
    *secondary = *primary;
  }

  // Update primary cache.
  primary->key = name;
  primary->value = code;
  return code;
}


Object* StubCache::ComputeLoadField(String* name,
                                    JSObject* receiver,
                                    JSObject* holder,
                                    int field_index) {
  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::LOAD_IC, FIELD);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    LoadStubCompiler compiler;
    code = compiler.CompileLoadField(receiver, holder, field_index, name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("LoadIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return code;
  }
  return Set(name, receiver->map(), Code::cast(code));
}


Object* StubCache::ComputeLoadCallback(String* name,
                                       JSObject* receiver,
                                       JSObject* holder,
                                       AccessorInfo* callback) {
  ASSERT(v8::ToCData<Address>(callback->getter()) != 0);
  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::LOAD_IC, CALLBACKS);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    LoadStubCompiler compiler;
    code = compiler.CompileLoadCallback(receiver, holder, callback, name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("LoadIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return code;
  }
  return Set(name, receiver->map(), Code::cast(code));
}


Object* StubCache::ComputeLoadConstant(String* name,
                                       JSObject* receiver,
                                       JSObject* holder,
                                       Object* value) {
  Code::Flags flags =
      Code::ComputeMonomorphicFlags(Code::LOAD_IC, CONSTANT_FUNCTION);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    LoadStubCompiler compiler;
    code = compiler.CompileLoadConstant(receiver, holder, value, name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("LoadIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return code;
  }
  return Set(name, receiver->map(), Code::cast(code));
}


Object* StubCache::ComputeLoadInterceptor(String* name,
                                          JSObject* receiver,
                                          JSObject* holder) {
  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::LOAD_IC, INTERCEPTOR);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    LoadStubCompiler compiler;
    code = compiler.CompileLoadInterceptor(receiver, holder, name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("LoadIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return code;
  }
  return Set(name, receiver->map(), Code::cast(code));
}


Object* StubCache::ComputeLoadNormal(String* name, JSObject* receiver) {
  Code* code = Builtins::builtin(Builtins::LoadIC_Normal);
  return Set(name, receiver->map(), code);
}


Object* StubCache::ComputeKeyedLoadField(String* name,
                                         JSObject* receiver,
                                         JSObject* holder,
                                         int field_index) {
  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::KEYED_LOAD_IC, FIELD);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    KeyedLoadStubCompiler compiler;
    code = compiler.CompileLoadField(name, receiver, holder, field_index);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("KeyedLoadIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return code;
}


Object* StubCache::ComputeKeyedLoadConstant(String* name,
                                            JSObject* receiver,
                                            JSObject* holder,
                                            Object* value) {
  Code::Flags flags =
      Code::ComputeMonomorphicFlags(Code::KEYED_LOAD_IC, CONSTANT_FUNCTION);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    KeyedLoadStubCompiler compiler;
    code = compiler.CompileLoadConstant(name, receiver, holder, value);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("KeyedLoadIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return code;
}


Object* StubCache::ComputeKeyedLoadInterceptor(String* name,
                                               JSObject* receiver,
                                               JSObject* holder) {
  Code::Flags flags =
      Code::ComputeMonomorphicFlags(Code::KEYED_LOAD_IC, INTERCEPTOR);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    KeyedLoadStubCompiler compiler;
    code = compiler.CompileLoadInterceptor(receiver, holder, name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("KeyedLoadIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return code;
}


Object* StubCache::ComputeKeyedLoadCallback(String* name,
                                            JSObject* receiver,
                                            JSObject* holder,
                                            AccessorInfo* callback) {
  Code::Flags flags =
      Code::ComputeMonomorphicFlags(Code::KEYED_LOAD_IC, CALLBACKS);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    KeyedLoadStubCompiler compiler;
    code = compiler.CompileLoadCallback(name, receiver, holder, callback);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("KeyedLoadIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return code;
}



Object* StubCache::ComputeKeyedLoadArrayLength(String* name,
                                               JSArray* receiver) {
  Code::Flags flags =
      Code::ComputeMonomorphicFlags(Code::KEYED_LOAD_IC, CALLBACKS);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    KeyedLoadStubCompiler compiler;
    code = compiler.CompileLoadArrayLength(name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("KeyedLoadIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return code;
}


Object* StubCache::ComputeKeyedLoadStringLength(String* name,
                                                String* receiver) {
  Code::Flags flags =
      Code::ComputeMonomorphicFlags(Code::KEYED_LOAD_IC, CALLBACKS);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    KeyedLoadStubCompiler compiler;
    code = compiler.CompileLoadStringLength(name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("KeyedLoadIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return code;
}


Object* StubCache::ComputeKeyedLoadFunctionPrototype(String* name,
                                                     JSFunction* receiver) {
  Code::Flags flags =
      Code::ComputeMonomorphicFlags(Code::KEYED_LOAD_IC, CALLBACKS);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    KeyedLoadStubCompiler compiler;
    code = compiler.CompileLoadFunctionPrototype(name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("KeyedLoadIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return code;
}


Object* StubCache::ComputeStoreField(String* name,
                                     JSObject* receiver,
                                     int field_index,
                                     Map* transition) {
  PropertyType type = (transition == NULL) ? FIELD : MAP_TRANSITION;
  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::STORE_IC, type);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    StoreStubCompiler compiler;
    code = compiler.CompileStoreField(receiver, field_index, transition, name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("StoreIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return Set(name, receiver->map(), Code::cast(code));
}


Object* StubCache::ComputeStoreCallback(String* name,
                                        JSObject* receiver,
                                        AccessorInfo* callback) {
  ASSERT(v8::ToCData<Address>(callback->setter()) != 0);
  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::STORE_IC, CALLBACKS);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    StoreStubCompiler compiler;
    code = compiler.CompileStoreCallback(receiver, callback, name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("StoreIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return Set(name, receiver->map(), Code::cast(code));
}


Object* StubCache::ComputeStoreInterceptor(String* name,
                                           JSObject* receiver) {
  Code::Flags flags =
      Code::ComputeMonomorphicFlags(Code::STORE_IC, INTERCEPTOR);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    StoreStubCompiler compiler;
    code = compiler.CompileStoreInterceptor(receiver, name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("StoreIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return Set(name, receiver->map(), Code::cast(code));
}


Object* StubCache::ComputeKeyedStoreField(String* name, JSObject* receiver,
                                          int field_index, Map* transition) {
  PropertyType type = (transition == NULL) ? FIELD : MAP_TRANSITION;
  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::KEYED_STORE_IC, type);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    KeyedStoreStubCompiler compiler;
    code = compiler.CompileStoreField(receiver, field_index, transition, name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("KeyedStoreIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return code;
}


Object* StubCache::ComputeCallConstant(int argc,
                                       String* name,
                                       Object* object,
                                       JSObject* holder,
                                       JSFunction* function) {
  // Compute the check type and the map.
  Map* map = IC::GetCodeCacheMapForObject(object);

  // Compute check type based on receiver/holder.
  StubCompiler::CheckType check = StubCompiler::RECEIVER_MAP_CHECK;
  if (object->IsString()) {
    check = StubCompiler::STRING_CHECK;
  } else if (object->IsNumber()) {
    check = StubCompiler::NUMBER_CHECK;
  } else if (object->IsBoolean()) {
    check = StubCompiler::BOOLEAN_CHECK;
  }

  Code::Flags flags =
      Code::ComputeMonomorphicFlags(Code::CALL_IC, CONSTANT_FUNCTION, argc);
  Object* code = map->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    if (object->IsJSObject()) {
      Object* opt =
          Top::LookupSpecialFunction(JSObject::cast(object), holder, function);
      if (opt->IsJSFunction()) {
        check = StubCompiler::JSARRAY_HAS_FAST_ELEMENTS_CHECK;
        function = JSFunction::cast(opt);
      }
    }
    // If the function hasn't been compiled yet, we cannot do it now
    // because it may cause GC. To avoid this issue, we return an
    // internal error which will make sure we do not update any
    // caches.
    if (!function->is_compiled()) return Failure::InternalError();
    // Compile the stub - only create stubs for fully compiled functions.
    CallStubCompiler compiler(argc);
    code = compiler.CompileCallConstant(object, holder, function, check);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("CallIC", Code::cast(code), name));
    Object* result = map->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return Set(name, map, Code::cast(code));
}


Object* StubCache::ComputeCallField(int argc,
                                    String* name,
                                    Object* object,
                                    JSObject* holder,
                                    int index) {
  // Compute the check type and the map.
  Map* map = IC::GetCodeCacheMapForObject(object);

  // TODO(1233596): We cannot do receiver map check for non-JS objects
  // because they may be represented as immediates without a
  // map. Instead, we check against the map in the holder.
  if (object->IsNumber() || object->IsBoolean() || object->IsString()) {
    object = holder;
  }

  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::CALL_IC, FIELD, argc);
  Object* code = map->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    CallStubCompiler compiler(argc);
    code = compiler.CompileCallField(object, holder, index, name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("CallIC", Code::cast(code), name));
    Object* result = map->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return Set(name, map, Code::cast(code));
}


Object* StubCache::ComputeCallInterceptor(int argc,
                                          String* name,
                                          Object* object,
                                          JSObject* holder) {
  // Compute the check type and the map.
  // If the object is a value, we use the prototype map for the cache.
  Map* map = IC::GetCodeCacheMapForObject(object);

  // TODO(1233596): We cannot do receiver map check for non-JS objects
  // because they may be represented as immediates without a
  // map. Instead, we check against the map in the holder.
  if (object->IsNumber() || object->IsBoolean() || object->IsString()) {
    object = holder;
  }

  Code::Flags flags =
      Code::ComputeMonomorphicFlags(Code::CALL_IC, INTERCEPTOR, argc);
  Object* code = map->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    CallStubCompiler compiler(argc);
    code = compiler.CompileCallInterceptor(object, holder, name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("CallIC", Code::cast(code), name));
    Object* result = map->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return Set(name, map, Code::cast(code));
}


Object* StubCache::ComputeCallNormal(int argc,
                                     String* name,
                                     JSObject* receiver) {
  Object* code = ComputeCallNormal(argc);
  if (code->IsFailure()) return code;
  return Set(name, receiver->map(), Code::cast(code));
}


static Object* GetProbeValue(Code::Flags flags) {
  Dictionary* dictionary = Heap::non_monomorphic_cache();
  int entry = dictionary->FindNumberEntry(flags);
  if (entry != -1) return dictionary->ValueAt(entry);
  return Heap::undefined_value();
}


static Object* ProbeCache(Code::Flags flags) {
  Object* probe = GetProbeValue(flags);
  if (probe != Heap::undefined_value()) return probe;
  // Seed the cache with an undefined value to make sure that any
  // generated code object can always be inserted into the cache
  // without causing  allocation failures.
  Object* result =
      Heap::non_monomorphic_cache()->AtNumberPut(flags,
                                                 Heap::undefined_value());
  if (result->IsFailure()) return result;
  Heap::set_non_monomorphic_cache(Dictionary::cast(result));
  return probe;
}


static Object* FillCache(Object* code) {
  if (code->IsCode()) {
    int entry =
        Heap::non_monomorphic_cache()->FindNumberEntry(
            Code::cast(code)->flags());
    // The entry must be present see comment in ProbeCache.
    ASSERT(entry != -1);
    ASSERT(Heap::non_monomorphic_cache()->ValueAt(entry) ==
           Heap::undefined_value());
    Heap::non_monomorphic_cache()->ValueAtPut(entry, code);
    CHECK(GetProbeValue(Code::cast(code)->flags()) == code);
  }
  return code;
}


Code* StubCache::FindCallInitialize(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::CALL_IC, UNINITIALIZED, NORMAL, argc);
  Object* result = ProbeCache(flags);
  ASSERT(!result->IsUndefined());
  // This might be called during the marking phase of the collector
  // hence the unchecked cast.
  return reinterpret_cast<Code*>(result);
}


Object* StubCache::ComputeCallInitialize(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::CALL_IC, UNINITIALIZED, NORMAL, argc);
  Object* probe = ProbeCache(flags);
  if (!probe->IsUndefined()) return probe;
  StubCompiler compiler;
  return FillCache(compiler.CompileCallInitialize(flags));
}


Object* StubCache::ComputeCallInitializeInLoop(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::CALL_IC, UNINITIALIZED_IN_LOOP, NORMAL, argc);
  Object* probe = ProbeCache(flags);
  if (!probe->IsUndefined()) return probe;
  StubCompiler compiler;
  return FillCache(compiler.CompileCallInitialize(flags));
}



Object* StubCache::ComputeCallPreMonomorphic(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::CALL_IC, PREMONOMORPHIC, NORMAL, argc);
  Object* probe = ProbeCache(flags);
  if (!probe->IsUndefined()) return probe;
  StubCompiler compiler;
  return FillCache(compiler.CompileCallPreMonomorphic(flags));
}


Object* StubCache::ComputeCallNormal(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::CALL_IC, MONOMORPHIC, NORMAL, argc);
  Object* probe = ProbeCache(flags);
  if (!probe->IsUndefined()) return probe;
  StubCompiler compiler;
  return FillCache(compiler.CompileCallNormal(flags));
}


Object* StubCache::ComputeCallMegamorphic(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::CALL_IC, MEGAMORPHIC, NORMAL, argc);
  Object* probe = ProbeCache(flags);
  if (!probe->IsUndefined()) return probe;
  StubCompiler compiler;
  return FillCache(compiler.CompileCallMegamorphic(flags));
}


Object* StubCache::ComputeCallMiss(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::STUB, MEGAMORPHIC, NORMAL, argc);
  Object* probe = ProbeCache(flags);
  if (!probe->IsUndefined()) return probe;
  StubCompiler compiler;
  return FillCache(compiler.CompileCallMiss(flags));
}


Object* StubCache::ComputeCallDebugBreak(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::CALL_IC, DEBUG_BREAK, NORMAL, argc);
  Object* probe = ProbeCache(flags);
  if (!probe->IsUndefined()) return probe;
  StubCompiler compiler;
  return FillCache(compiler.CompileCallDebugBreak(flags));
}


Object* StubCache::ComputeCallDebugPrepareStepIn(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::CALL_IC, DEBUG_PREPARE_STEP_IN, NORMAL, argc);
  Object* probe = ProbeCache(flags);
  if (!probe->IsUndefined()) return probe;
  StubCompiler compiler;
  return FillCache(compiler.CompileCallDebugPrepareStepIn(flags));
}


Object* StubCache::ComputeLazyCompile(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::STUB, UNINITIALIZED, NORMAL, argc);
  Object* probe = ProbeCache(flags);
  if (!probe->IsUndefined()) return probe;
  StubCompiler compiler;
  Object* result = FillCache(compiler.CompileLazyCompile(flags));
  if (result->IsCode()) {
    Code* code = Code::cast(result);
    USE(code);
    LOG(CodeCreateEvent("LazyCompile", code, code->arguments_count()));
  }
  return result;
}


void StubCache::Clear() {
  for (int i = 0; i < kPrimaryTableSize; i++) {
    primary_[i].key = Heap::empty_string();
    primary_[i].value = Builtins::builtin(Builtins::Illegal);
  }
  for (int j = 0; j < kSecondaryTableSize; j++) {
    secondary_[j].key = Heap::empty_string();
    secondary_[j].value = Builtins::builtin(Builtins::Illegal);
  }
}


// ------------------------------------------------------------------------
// StubCompiler implementation.


// Support function for computing call IC miss stubs.
Handle<Code> ComputeCallMiss(int argc) {
  CALL_HEAP_FUNCTION(StubCache::ComputeCallMiss(argc), Code);
}



Object* LoadCallbackProperty(Arguments args) {
  Handle<JSObject> recv = args.at<JSObject>(0);
  AccessorInfo* callback = AccessorInfo::cast(args[1]);
  Address getter_address = v8::ToCData<Address>(callback->getter());
  v8::AccessorGetter fun = FUNCTION_CAST<v8::AccessorGetter>(getter_address);
  ASSERT(fun != NULL);
  Handle<String> name = args.at<String>(2);
  Handle<JSObject> holder = args.at<JSObject>(3);
  HandleScope scope;
  Handle<Object> data(callback->data());
  LOG(ApiNamedPropertyAccess("load", *recv, *name));
  // NOTE: If we can align the structure of an AccessorInfo with the
  // locations of the arguments to this function maybe we don't have
  // to explicitly create the structure but can just pass a pointer
  // into the stack.
  v8::AccessorInfo info(v8::Utils::ToLocal(recv),
                        v8::Utils::ToLocal(data),
                        v8::Utils::ToLocal(holder));
  v8::Handle<v8::Value> result;
  {
    // Leaving JavaScript.
    VMState state(OTHER);
    result = fun(v8::Utils::ToLocal(name), info);
  }
  RETURN_IF_SCHEDULED_EXCEPTION();
  if (result.IsEmpty()) return Heap::undefined_value();
  return *v8::Utils::OpenHandle(*result);
}


Object* StoreCallbackProperty(Arguments args) {
  Handle<JSObject> recv = args.at<JSObject>(0);
  AccessorInfo* callback = AccessorInfo::cast(args[1]);
  Address setter_address = v8::ToCData<Address>(callback->setter());
  v8::AccessorSetter fun = FUNCTION_CAST<v8::AccessorSetter>(setter_address);
  ASSERT(fun != NULL);
  Handle<String> name = args.at<String>(2);
  Handle<Object> value = args.at<Object>(3);
  HandleScope scope;
  Handle<Object> data(callback->data());
  LOG(ApiNamedPropertyAccess("store", *recv, *name));
  v8::AccessorInfo info(v8::Utils::ToLocal(recv),
                        v8::Utils::ToLocal(data),
                        v8::Utils::ToLocal(recv));
  {
    // Leaving JavaScript.
    VMState state(OTHER);
    fun(v8::Utils::ToLocal(name), v8::Utils::ToLocal(value), info);
  }
  RETURN_IF_SCHEDULED_EXCEPTION();
  return *value;
}


Object* LoadInterceptorProperty(Arguments args) {
  JSObject* recv = JSObject::cast(args[0]);
  JSObject* holder = JSObject::cast(args[1]);
  String* name = String::cast(args[2]);
  ASSERT(holder->HasNamedInterceptor());
  PropertyAttributes attr = NONE;
  Object* result = holder->GetPropertyWithInterceptor(recv, name, &attr);

  if (result->IsFailure()) return result;

  // If the property is present, return it.
  if (attr != ABSENT) return result;

  // If the top frame is an internal frame, this is really a call
  // IC. In this case, we simply return the undefined result which
  // will lead to an exception when trying to invoke the result as a
  // function.
  StackFrameIterator it;
  it.Advance();  // skip exit frame
  if (it.frame()->is_internal()) return result;

  // If the load is non-contextual, just return the undefined result.
  // Note that both keyed and non-keyed loads may end up here, so we
  // can't use either LoadIC or KeyedLoadIC constructors.
  IC ic(IC::NO_EXTRA_FRAME);
  ASSERT(ic.target()->is_load_stub() || ic.target()->is_keyed_load_stub());
  if (!ic.is_contextual()) return result;

  // Throw a reference error.
  {
    HandleScope scope;
    // We cannot use the raw name pointer here since getting the
    // property might cause a GC.  However, we can get the name from
    // the stack using the arguments object.
    Handle<String> name_handle = args.at<String>(2);
    Handle<Object> error =
        Factory::NewReferenceError("not_defined",
                                   HandleVector(&name_handle, 1));
    return Top::Throw(*error);
  }
}


Object* StoreInterceptorProperty(Arguments args) {
  JSObject* recv = JSObject::cast(args[0]);
  String* name = String::cast(args[1]);
  Object* value = args[2];
  ASSERT(recv->HasNamedInterceptor());
  PropertyAttributes attr = NONE;
  Object* result = recv->SetPropertyWithInterceptor(name, value, attr);
  return result;
}


Object* StubCompiler::CompileCallInitialize(Code::Flags flags) {
  HandleScope scope;
  int argc = Code::ExtractArgumentsCountFromFlags(flags);
  CallIC::GenerateInitialize(masm(), argc);
  Object* result = GetCodeWithFlags(flags, "CompileCallInitialize");
  if (!result->IsFailure()) {
    Counters::call_initialize_stubs.Increment();
    Code* code = Code::cast(result);
    USE(code);
    LOG(CodeCreateEvent("CallInitialize", code, code->arguments_count()));
  }
  return result;
}


Object* StubCompiler::CompileCallPreMonomorphic(Code::Flags flags) {
  HandleScope scope;
  int argc = Code::ExtractArgumentsCountFromFlags(flags);
  CallIC::GenerateInitialize(masm(), argc);
  Object* result = GetCodeWithFlags(flags, "CompileCallPreMonomorphic");
  if (!result->IsFailure()) {
    Counters::call_premonomorphic_stubs.Increment();
    Code* code = Code::cast(result);
    USE(code);
    LOG(CodeCreateEvent("CallPreMonomorphic", code, code->arguments_count()));
  }
  return result;
}


Object* StubCompiler::CompileCallNormal(Code::Flags flags) {
  HandleScope scope;
  int argc = Code::ExtractArgumentsCountFromFlags(flags);
  CallIC::GenerateNormal(masm(), argc);
  Object* result = GetCodeWithFlags(flags, "CompileCallNormal");
  if (!result->IsFailure()) {
    Counters::call_normal_stubs.Increment();
    Code* code = Code::cast(result);
    USE(code);
    LOG(CodeCreateEvent("CallNormal", code, code->arguments_count()));
  }
  return result;
}


Object* StubCompiler::CompileCallMegamorphic(Code::Flags flags) {
  HandleScope scope;
  int argc = Code::ExtractArgumentsCountFromFlags(flags);
  CallIC::GenerateMegamorphic(masm(), argc);
  Object* result = GetCodeWithFlags(flags, "CompileCallMegamorphic");
  if (!result->IsFailure()) {
    Counters::call_megamorphic_stubs.Increment();
    Code* code = Code::cast(result);
    USE(code);
    LOG(CodeCreateEvent("CallMegamorphic", code, code->arguments_count()));
  }
  return result;
}


Object* StubCompiler::CompileCallMiss(Code::Flags flags) {
  HandleScope scope;
  int argc = Code::ExtractArgumentsCountFromFlags(flags);
  CallIC::GenerateMiss(masm(), argc);
  Object* result = GetCodeWithFlags(flags, "CompileCallMiss");
  if (!result->IsFailure()) {
    Counters::call_megamorphic_stubs.Increment();
    Code* code = Code::cast(result);
    USE(code);
    LOG(CodeCreateEvent("CallMiss", code, code->arguments_count()));
  }
  return result;
}


Object* StubCompiler::CompileCallDebugBreak(Code::Flags flags) {
  HandleScope scope;
  Debug::GenerateCallICDebugBreak(masm());
  Object* result = GetCodeWithFlags(flags, "CompileCallDebugBreak");
  if (!result->IsFailure()) {
    Code* code = Code::cast(result);
    USE(code);
    LOG(CodeCreateEvent("CallDebugBreak", code, code->arguments_count()));
  }
  return result;
}


Object* StubCompiler::CompileCallDebugPrepareStepIn(Code::Flags flags) {
  HandleScope scope;
  // Use the same code for the the step in preparations as we do for
  // the miss case.
  int argc = Code::ExtractArgumentsCountFromFlags(flags);
  CallIC::GenerateMiss(masm(), argc);
  Object* result = GetCodeWithFlags(flags, "CompileCallDebugPrepareStepIn");
  if (!result->IsFailure()) {
    Code* code = Code::cast(result);
    USE(code);
    LOG(CodeCreateEvent("CallDebugPrepareStepIn", code,
                        code->arguments_count()));
  }
  return result;
}


Object* StubCompiler::GetCodeWithFlags(Code::Flags flags, const char* name) {
  CodeDesc desc;
  masm_.GetCode(&desc);
  Object* result = Heap::CreateCode(desc, NULL, flags, masm_.CodeObject());
#ifdef ENABLE_DISASSEMBLER
  if (FLAG_print_code_stubs && !result->IsFailure()) {
    Code::cast(result)->Disassemble(name);
  }
#endif
  return result;
}


Object* StubCompiler::GetCodeWithFlags(Code::Flags flags, String* name) {
  if (FLAG_print_code_stubs && (name != NULL)) {
    return GetCodeWithFlags(flags, *name->ToCString());
  }
  return GetCodeWithFlags(flags, reinterpret_cast<char*>(NULL));
}


Object* LoadStubCompiler::GetCode(PropertyType type, String* name) {
  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::LOAD_IC, type);
  return GetCodeWithFlags(flags, name);
}


Object* KeyedLoadStubCompiler::GetCode(PropertyType type, String* name) {
  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::KEYED_LOAD_IC, type);
  return GetCodeWithFlags(flags, name);
}


Object* StoreStubCompiler::GetCode(PropertyType type, String* name) {
  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::STORE_IC, type);
  return GetCodeWithFlags(flags, name);
}


Object* KeyedStoreStubCompiler::GetCode(PropertyType type, String* name) {
  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::KEYED_STORE_IC, type);
  return GetCodeWithFlags(flags, name);
}


Object* CallStubCompiler::GetCode(PropertyType type, String* name) {
  int argc = arguments_.immediate();
  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::CALL_IC, type, argc);
  return GetCodeWithFlags(flags, name);
}


} }  // namespace v8::internal