[deoptimizer] Remove arguments object materialization.

This removes specialized support for materializing arguments objects.
For TurboFan we use the generic escape analysis mechanism when such
objects are materialized already, only Crankshaft used this deprecated
mechanism.

R=jarin@chromium.org
BUG=v8:6408

Change-Id: Ibed52a028752e667b05a60fa7cf0275a6a372897
Reviewed-on: https://chromium-review.googlesource.com/548595Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46215}

src/deoptimizer.cc

@@ -2481,11 +2481,6 @@ void Translation::BeginCompiledStubFrame(int height) {
 }
 
 
-void Translation::BeginArgumentsObject(int args_length) {
-  buffer_->Add(ARGUMENTS_OBJECT);
-  buffer_->Add(args_length);
-}
-
 void Translation::ArgumentsElements(bool is_rest) {
   buffer_->Add(ARGUMENTS_ELEMENTS);
   buffer_->Add(is_rest);
@@ -2582,16 +2577,6 @@ void Translation::StoreLiteral(int literal_id) {
 }
 
 
-void Translation::StoreArgumentsObject(bool args_known,
-                                       int args_index,
-                                       int args_length) {
-  buffer_->Add(ARGUMENTS_OBJECT);
-  buffer_->Add(args_known);
-  buffer_->Add(args_index);
-  buffer_->Add(args_length);
-}
-
-
 void Translation::StoreJSFrameFunction() {
   StoreStackSlot((StandardFrameConstants::kCallerPCOffset -
                   StandardFrameConstants::kFunctionOffset) /
@@ -2603,7 +2588,6 @@ int Translation::NumberOfOperandsFor(Opcode opcode) {
     case GETTER_STUB_FRAME:
     case SETTER_STUB_FRAME:
     case DUPLICATED_OBJECT:
-    case ARGUMENTS_OBJECT:
     case CAPTURED_OBJECT:
     case REGISTER:
     case INT32_REGISTER:
@@ -2860,15 +2844,6 @@ int Deoptimizer::ComputeSourcePositionFromBytecodeArray(
       ->SourcePosition(node_id.ToInt());
 }
 
-// static
-TranslatedValue TranslatedValue::NewArgumentsObject(TranslatedState* container,
-                                                    int length,
-                                                    int object_index) {
-  TranslatedValue slot(container, kArgumentsObject);
-  slot.materialization_info_ = {object_index, length};
-  return slot;
-}
-
 // static
 TranslatedValue TranslatedValue::NewDeferredObject(TranslatedState* container,
                                                    int length,
@@ -2979,14 +2954,13 @@ Float64 TranslatedValue::double_value() const {
 
 
 int TranslatedValue::object_length() const {
-  DCHECK(kind() == kArgumentsObject || kind() == kCapturedObject);
+  DCHECK(kind() == kCapturedObject);
   return materialization_info_.length_;
 }
 
 
 int TranslatedValue::object_index() const {
-  DCHECK(kind() == kArgumentsObject || kind() == kCapturedObject ||
-         kind() == kDuplicatedObject);
+  DCHECK(kind() == kCapturedObject || kind() == kDuplicatedObject);
   return materialization_info_.id_;
 }
 
@@ -3055,7 +3029,6 @@ Handle<Object> TranslatedValue::GetValue() {
       return value_.ToHandleChecked();
     }
 
-    case TranslatedValue::kArgumentsObject:
     case TranslatedValue::kCapturedObject:
     case TranslatedValue::kDuplicatedObject:
       return container_->MaterializeObjectAt(object_index());
@@ -3104,7 +3077,6 @@ void TranslatedValue::MaterializeSimple() {
 
     case kCapturedObject:
     case kDuplicatedObject:
-    case kArgumentsObject:
     case kInvalid:
     case kTagged:
     case kBoolBit:
@@ -3118,7 +3090,6 @@ bool TranslatedValue::IsMaterializedObject() const {
   switch (kind()) {
     case kCapturedObject:
     case kDuplicatedObject:
-    case kArgumentsObject:
       return true;
     default:
       return false;
@@ -3131,7 +3102,7 @@ bool TranslatedValue::IsMaterializableByDebugger() const {
 }
 
 int TranslatedValue::GetChildrenCount() const {
-  if (kind() == kCapturedObject || kind() == kArgumentsObject) {
+  if (kind() == kCapturedObject) {
     return object_length();
   } else {
     return 0;
@@ -3399,7 +3370,6 @@ TranslatedFrame TranslatedState::CreateNextTranslatedFrame(
 
     case Translation::BEGIN:
     case Translation::DUPLICATED_OBJECT:
-    case Translation::ARGUMENTS_OBJECT:
     case Translation::ARGUMENTS_ELEMENTS:
     case Translation::ARGUMENTS_LENGTH:
     case Translation::CAPTURED_OBJECT:
@@ -3549,20 +3519,6 @@ int TranslatedState::CreateNextTranslatedValue(
       return translated_value.GetChildrenCount();
     }
 
-    case Translation::ARGUMENTS_OBJECT: {
-      int arg_count = iterator->Next();
-      int object_index = static_cast<int>(object_positions_.size());
-      if (trace_file != nullptr) {
-        PrintF(trace_file, "arguments object #%d (length = %d)", object_index,
-               arg_count);
-      }
-      object_positions_.push_back({frame_index, value_index});
-      TranslatedValue translated_value =
-          TranslatedValue::NewArgumentsObject(this, arg_count, object_index);
-      frame.Add(translated_value);
-      return translated_value.GetChildrenCount();
-    }
-
     case Translation::ARGUMENTS_ELEMENTS: {
       bool is_rest = iterator->Next();
       CreateArgumentsElementsTranslatedValues(frame_index, fp, is_rest,
@@ -3812,11 +3768,8 @@ int TranslatedState::CreateNextTranslatedValue(
   return translated_value.GetChildrenCount();
 }
 
-
 TranslatedState::TranslatedState(JavaScriptFrame* frame)
-    : isolate_(nullptr),
-      stack_frame_pointer_(nullptr),
-      has_adapted_arguments_(false) {
+    : isolate_(nullptr), stack_frame_pointer_(nullptr) {
   int deopt_index = Safepoint::kNoDeoptimizationIndex;
   DeoptimizationInputData* data =
       static_cast<OptimizedFrame*>(frame)->GetDeoptimizationData(&deopt_index);
@@ -3828,11 +3781,8 @@ TranslatedState::TranslatedState(JavaScriptFrame* frame)
        frame->function()->shared()->internal_formal_parameter_count());
 }
 
-
 TranslatedState::TranslatedState()
-    : isolate_(nullptr),
-      stack_frame_pointer_(nullptr),
-      has_adapted_arguments_(false) {}
+    : isolate_(nullptr), stack_frame_pointer_(nullptr) {}
 
 void TranslatedState::Init(Address input_frame_pointer,
                            TranslationIterator* iterator,
@@ -3912,7 +3862,6 @@ void TranslatedState::Prepare(bool has_adapted_arguments,
   for (auto& frame : frames_) frame.Handlify();
 
   stack_frame_pointer_ = stack_frame_pointer;
-  has_adapted_arguments_ = has_adapted_arguments;
 
   UpdateFromPreviouslyMaterializedObjects();
 }
@@ -4324,29 +4273,6 @@ Handle<Object> TranslatedState::MaterializeAt(int frame_index,
       return value;
     }
 
-    case TranslatedValue::kArgumentsObject: {
-      int length = slot->GetChildrenCount();
-      Handle<JSObject> arguments;
-      if (GetAdaptedArguments(&arguments, frame_index)) {
-        // Store the materialized object and consume the nested values.
-        for (int i = 0; i < length; ++i) {
-          MaterializeAt(frame_index, value_index);
-        }
-      } else {
-        Handle<JSFunction> function =
-            Handle<JSFunction>::cast(frame->front().GetValue());
-        arguments = isolate_->factory()->NewArgumentsObject(function, length);
-        Handle<FixedArray> array = isolate_->factory()->NewFixedArray(length);
-        DCHECK_EQ(array->length(), length);
-        arguments->set_elements(*array);
-        for (int i = 0; i < length; ++i) {
-          Handle<Object> value = MaterializeAt(frame_index, value_index);
-          array->set(i, *value);
-        }
-      }
-      slot->value_ = arguments;
-      return arguments;
-    }
     case TranslatedValue::kCapturedObject: {
       // The map must be a tagged object.
       CHECK(frame->values_[*value_index].kind() == TranslatedValue::kTagged);
@@ -4388,45 +4314,6 @@ Handle<Object> TranslatedState::MaterializeObjectAt(int object_index) {
   return MaterializeAt(pos.frame_index_, &(pos.value_index_));
 }
 
-bool TranslatedState::GetAdaptedArguments(Handle<JSObject>* result,
-                                          int frame_index) {
-  if (frame_index == 0) {
-    // Top level frame -> we need to go to the parent frame on the stack.
-    if (!has_adapted_arguments_) return false;
-
-    // This is top level frame, so we need to go to the stack to get
-    // this function's argument. (Note that this relies on not inlining
-    // recursive functions!)
-    Handle<JSFunction> function =
-        Handle<JSFunction>::cast(frames_[frame_index].front().GetValue());
-    *result = Accessors::FunctionGetArguments(function);
-    return true;
-  } else {
-    TranslatedFrame* previous_frame = &(frames_[frame_index]);
-    if (previous_frame->kind() != TranslatedFrame::kArgumentsAdaptor) {
-      return false;
-    }
-    // We get the adapted arguments from the parent translation.
-    int length = previous_frame->height();
-    Handle<JSFunction> function =
-        Handle<JSFunction>::cast(previous_frame->front().GetValue());
-    Handle<JSObject> arguments =
-        isolate_->factory()->NewArgumentsObject(function, length);
-    Handle<FixedArray> array = isolate_->factory()->NewFixedArray(length);
-    arguments->set_elements(*array);
-    TranslatedFrame::iterator arg_iterator = previous_frame->begin();
-    arg_iterator++;  // Skip function.
-    for (int i = 0; i < length; ++i) {
-      Handle<Object> value = arg_iterator->GetValue();
-      array->set(i, *value);
-      arg_iterator++;
-    }
-    CHECK(arg_iterator == previous_frame->end());
-    *result = arguments;
-    return true;
-  }
-}
-
 TranslatedFrame* TranslatedState::GetArgumentsInfoFromJSFrameIndex(
     int jsframe_index, int* args_count) {
   for (size_t i = 0; i < frames_.size(); i++) {

src/deoptimizer.h

@@ -74,14 +74,12 @@ class TranslatedValue {
     kBoolBit,
     kFloat,
     kDouble,
-    kCapturedObject,    // Object captured by the escape analysis.
-                        // The number of nested objects can be obtained
-                        // with the DeferredObjectLength() method
-                        // (the values of the nested objects follow
-                        // this value in the depth-first order.)
-    kDuplicatedObject,  // Duplicated object of a deferred object.
-    kArgumentsObject    // Arguments object - only used to keep indexing
-                        // in sync, it should not be materialized.
+    kCapturedObject,   // Object captured by the escape analysis.
+                       // The number of nested objects can be obtained
+                       // with the DeferredObjectLength() method
+                       // (the values of the nested objects follow
+                       // this value in the depth-first order.)
+    kDuplicatedObject  // Duplicated object of a deferred object.
   };
 
   TranslatedValue(TranslatedState* container, Kind kind)
@@ -90,8 +88,6 @@ class TranslatedValue {
   void Handlify();
   int GetChildrenCount() const;
 
-  static TranslatedValue NewArgumentsObject(TranslatedState* container,
-                                            int length, int object_index);
   static TranslatedValue NewDeferredObject(TranslatedState* container,
                                            int length, int object_index);
   static TranslatedValue NewDuplicateObject(TranslatedState* container, int id);
@@ -118,7 +114,7 @@ class TranslatedValue {
 
   struct MaterializedObjectInfo {
     int id_;
-    int length_;  // Applies only to kArgumentsObject or kCapturedObject kinds.
+    int length_;  // Applies only to kCapturedObject kinds.
   };
 
   union {
@@ -132,8 +128,7 @@ class TranslatedValue {
     Float32 float_value_;
     // kind is kDouble
     Float64 double_value_;
-    // kind is kDuplicatedObject or kArgumentsObject or
-    // kCapturedObject.
+    // kind is kDuplicatedObject or kCapturedObject.
     MaterializedObjectInfo materialization_info_;
   };
 
@@ -333,7 +328,6 @@ class TranslatedState {
   class CapturedObjectMaterializer;
   Handle<Object> MaterializeCapturedObjectAt(TranslatedValue* slot,
                                              int frame_index, int* value_index);
-  bool GetAdaptedArguments(Handle<JSObject>* result, int frame_index);
 
   static uint32_t GetUInt32Slot(Address fp, int slot_index);
   static Float32 GetFloatSlot(Address fp, int slot_index);
@@ -342,7 +336,6 @@ class TranslatedState {
   std::vector<TranslatedFrame> frames_;
   Isolate* isolate_;
   Address stack_frame_pointer_;
-  bool has_adapted_arguments_;
   int formal_parameter_count_;
 
   struct ObjectPosition {
@@ -931,7 +924,6 @@ class TranslationIterator BASE_EMBEDDED {
   V(TAIL_CALLER_FRAME)                      \
   V(COMPILED_STUB_FRAME)                    \
   V(DUPLICATED_OBJECT)                      \
-  V(ARGUMENTS_OBJECT)                       \
   V(ARGUMENTS_ELEMENTS)                     \
   V(ARGUMENTS_LENGTH)                       \
   V(CAPTURED_OBJECT)                        \
@@ -984,7 +976,6 @@ class Translation BASE_EMBEDDED {
                                                int literal_id, unsigned height);
   void BeginGetterStubFrame(int literal_id);
   void BeginSetterStubFrame(int literal_id);
-  void BeginArgumentsObject(int args_length);
   void ArgumentsElements(bool is_rest);
   void ArgumentsLength(bool is_rest);
   void BeginCapturedObject(int length);
@@ -1002,7 +993,6 @@ class Translation BASE_EMBEDDED {
   void StoreFloatStackSlot(int index);
   void StoreDoubleStackSlot(int index);
   void StoreLiteral(int literal_id);
-  void StoreArgumentsObject(bool args_known, int args_index, int args_length);
   void StoreJSFrameFunction();
 
   Zone* zone() const { return zone_; }

src/objects.cc

@@ -14242,7 +14242,6 @@ void DeoptimizationInputData::DeoptimizationInputDataPrint(
           break;
         }
 
-        case Translation::ARGUMENTS_OBJECT:
         case Translation::CAPTURED_OBJECT: {
           int args_length = iterator.Next();
           os << "{length=" << args_length << "}";