[csa] Minor refactoring to prepare for the Object.assign CL.

1) Add exit point parameter to EmitGenericPropertyStore(),
2) carve TryLookupPropertyInSimpleObject() out of TryLookupProperty().

Bug: v8:5988
Change-Id: I6cef48731c27e5bb72dce5eaa0169fbf59787ed7
Reviewed-on: https://chromium-review.googlesource.com/997747Reviewed-by: Marja Hölttä <marja@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52448}

src/code-stub-assembler.cc

@@ -6997,20 +6997,21 @@ void CodeStubAssembler::Lookup(TNode<Name> unique_name, TNode<Array> array,
   }
 }
 
-void CodeStubAssembler::TryLookupProperty(
-    Node* object, Node* map, Node* instance_type, Node* unique_name,
-    Label* if_found_fast, Label* if_found_dict, Label* if_found_global,
+void CodeStubAssembler::TryLookupPropertyInSimpleObject(
+    TNode<JSObject> object, TNode<Map> map, TNode<Name> unique_name,
+    Label* if_found_fast, Label* if_found_dict,
     TVariable<HeapObject>* var_meta_storage, TVariable<IntPtrT>* var_name_index,
-    Label* if_not_found, Label* if_bailout) {
-  Label if_objectisspecial(this);
-  GotoIf(IsSpecialReceiverInstanceType(instance_type), &if_objectisspecial);
+    Label* if_not_found) {
+  CSA_ASSERT(
+      this,
+      Word32BinaryNot(IsSpecialReceiverInstanceType(LoadMapInstanceType(map))));
 
   uint32_t mask =
       Map::HasNamedInterceptorBit::kMask | Map::IsAccessCheckNeededBit::kMask;
   CSA_ASSERT(this, Word32BinaryNot(IsSetWord32(LoadMapBitField(map), mask)));
   USE(mask);
 
-  Node* bit_field3 = LoadMapBitField3(map);
+  TNode<Uint32T> bit_field3 = LoadMapBitField3(map);
   Label if_isfastmap(this), if_isslowmap(this);
   Branch(IsSetWord32<Map::IsDictionaryMapBit>(bit_field3), &if_isslowmap,
          &if_isfastmap);
@@ -7030,6 +7031,21 @@ void CodeStubAssembler::TryLookupProperty(
     NameDictionaryLookup<NameDictionary>(dictionary, unique_name, if_found_dict,
                                          var_name_index, if_not_found);
   }
+}
+
+void CodeStubAssembler::TryLookupProperty(
+    SloppyTNode<JSObject> object, SloppyTNode<Map> map,
+    SloppyTNode<Int32T> instance_type, SloppyTNode<Name> unique_name,
+    Label* if_found_fast, Label* if_found_dict, Label* if_found_global,
+    TVariable<HeapObject>* var_meta_storage, TVariable<IntPtrT>* var_name_index,
+    Label* if_not_found, Label* if_bailout) {
+  Label if_objectisspecial(this);
+  GotoIf(IsSpecialReceiverInstanceType(instance_type), &if_objectisspecial);
+
+  TryLookupPropertyInSimpleObject(object, map, unique_name, if_found_fast,
+                                  if_found_dict, var_meta_storage,
+                                  var_name_index, if_not_found);
+
   BIND(&if_objectisspecial);
   {
     // Handle global object here and bailout for other special objects.
@@ -7037,7 +7053,7 @@ void CodeStubAssembler::TryLookupProperty(
               if_bailout);
 
     // Handle interceptors and access checks in runtime.
-    Node* bit_field = LoadMapBitField(map);
+    TNode<Int32T> bit_field = LoadMapBitField(map);
     int mask =
         Map::HasNamedInterceptorBit::kMask | Map::IsAccessCheckNeededBit::kMask;
     GotoIf(IsSetWord32(bit_field, mask), if_bailout);
@@ -7238,10 +7254,9 @@ void CodeStubAssembler::LoadPropertyFromGlobalDictionary(Node* dictionary,
 // |value| is the property backing store's contents, which is either a value
 // or an accessor pair, as specified by |details|.
 // Returns either the original value, or the result of the getter call.
-Node* CodeStubAssembler::CallGetterIfAccessor(Node* value, Node* details,
-                                              Node* context, Node* receiver,
-                                              Label* if_bailout,
-                                              GetOwnPropertyMode mode) {
+TNode<Object> CodeStubAssembler::CallGetterIfAccessor(
+    Node* value, Node* details, Node* context, Node* receiver,
+    Label* if_bailout, GetOwnPropertyMode mode) {
   VARIABLE(var_value, MachineRepresentation::kTagged, value);
   Label done(this), if_accessor_info(this, Label::kDeferred);
 
@@ -7339,7 +7354,7 @@ Node* CodeStubAssembler::CallGetterIfAccessor(Node* value, Node* details,
   }
 
   BIND(&done);
-  return var_value.value();
+  return UncheckedCast<Object>(var_value.value());
 }
 
 void CodeStubAssembler::TryGetOwnProperty(

src/code-stub-assembler.h

@@ -1710,13 +1710,24 @@ class V8_EXPORT_PRIVATE CodeStubAssembler : public compiler::CodeAssembler {
   //
   // Note: this code does not check if the global dictionary points to deleted
   // entry! This has to be done by the caller.
-  void TryLookupProperty(Node* object, Node* map, Node* instance_type,
-                         Node* unique_name, Label* if_found_fast,
+  void TryLookupProperty(SloppyTNode<JSObject> object, SloppyTNode<Map> map,
+                         SloppyTNode<Int32T> instance_type,
+                         SloppyTNode<Name> unique_name, Label* if_found_fast,
                          Label* if_found_dict, Label* if_found_global,
                          TVariable<HeapObject>* var_meta_storage,
                          TVariable<IntPtrT>* var_name_index,
                          Label* if_not_found, Label* if_bailout);
 
+  // This is a building block for TryLookupProperty() above. Supports only
+  // non-special fast and dictionary objects.
+  void TryLookupPropertyInSimpleObject(TNode<JSObject> object, TNode<Map> map,
+                                       TNode<Name> unique_name,
+                                       Label* if_found_fast,
+                                       Label* if_found_dict,
+                                       TVariable<HeapObject>* var_meta_storage,
+                                       TVariable<IntPtrT>* var_name_index,
+                                       Label* if_not_found);
+
   // This method jumps to if_found if the element is known to exist. To
   // if_absent if it's known to not exist. To if_not_found if the prototype
   // chain needs to be checked. And if_bailout if the lookup is unsupported.
@@ -2069,9 +2080,9 @@ class V8_EXPORT_PRIVATE CodeStubAssembler : public compiler::CodeAssembler {
   TNode<Uint32T> DescriptorArrayGetDetails(TNode<DescriptorArray> descriptors,
                                            TNode<Uint32T> descriptor_number);
 
-  Node* CallGetterIfAccessor(Node* value, Node* details, Node* context,
-                             Node* receiver, Label* if_bailout,
-                             GetOwnPropertyMode mode = kCallJSGetter);
+  TNode<Object> CallGetterIfAccessor(Node* value, Node* details, Node* context,
+                                     Node* receiver, Label* if_bailout,
+                                     GetOwnPropertyMode mode = kCallJSGetter);
 
   TNode<IntPtrT> TryToIntptr(Node* key, Label* miss);
 

src/ic/accessor-assembler.cc

@@ -894,6 +894,7 @@ void AccessorAssembler::HandleStoreICHandlerCase(
     }
     BIND(&store_transition);
     HandleStoreICTransitionMapHandlerCase(p, map_or_property_cell, miss, false);
+    Return(p->value);
   }
 }
 
@@ -949,7 +950,6 @@ void AccessorAssembler::HandleStoreICTransitionMapHandlerCase(
   OverwriteExistingFastDataProperty(p->receiver, transition_map, descriptors,
                                     last_key_index, details, p->value, miss,
                                     true);
-  Return(p->value);
 }
 
 void AccessorAssembler::CheckFieldType(Node* descriptors, Node* name_index,

src/ic/keyed-store-generic.cc

@@ -41,7 +41,15 @@ class KeyedStoreGenericAssembler : public AccessorAssembler {
                                Node* value, Node* context, Label* slow);
 
   void EmitGenericPropertyStore(Node* receiver, Node* receiver_map,
-                                const StoreICParameters* p, Label* slow);
+                                const StoreICParameters* p,
+                                ExitPoint* exit_point, Label* slow,
+                                bool assume_strict_language_mode = false);
+
+  void EmitGenericPropertyStore(Node* receiver, Node* receiver_map,
+                                const StoreICParameters* p, Label* slow) {
+    ExitPoint direct_exit(this);
+    EmitGenericPropertyStore(receiver, receiver_map, p, &direct_exit, slow);
+  }
 
   void BranchIfPrototypesHaveNonFastElements(Node* receiver_map,
                                              Label* non_fast_elements,
@@ -611,7 +619,7 @@ void KeyedStoreGenericAssembler::LookupPropertyOnPrototypeChain(
 
 void KeyedStoreGenericAssembler::EmitGenericPropertyStore(
     Node* receiver, Node* receiver_map, const StoreICParameters* p,
-    Label* slow) {
+    ExitPoint* exit_point, Label* slow, bool assume_strict_language_mode) {
   VARIABLE(var_accessor_pair, MachineRepresentation::kTagged);
   VARIABLE(var_accessor_holder, MachineRepresentation::kTagged);
   Label stub_cache(this), fast_properties(this), dictionary_properties(this),
@@ -651,7 +659,7 @@ void KeyedStoreGenericAssembler::EmitGenericPropertyStore(
         OverwriteExistingFastDataProperty(receiver, receiver_map, descriptors,
                                           name_index, details, p->value, slow,
                                           false);
-        Return(p->value);
+        exit_point->Return(p->value);
       }
     }
     BIND(&lookup_transition);
@@ -721,6 +729,7 @@ void KeyedStoreGenericAssembler::EmitGenericPropertyStore(
         // Validate the transition handler candidate and apply the transition.
         HandleStoreICTransitionMapHandlerCase(p, var_transition_map.value(),
                                               slow, true);
+        exit_point->Return(p->value);
       }
     }
   }
@@ -754,7 +763,7 @@ void KeyedStoreGenericAssembler::EmitGenericPropertyStore(
         CheckForAssociatedProtector(p->name, slow);
         StoreValueByKeyIndex<NameDictionary>(properties, var_name_index.value(),
                                              p->value);
-        Return(p->value);
+        exit_point->Return(p->value);
       }
     }
 
@@ -774,11 +783,11 @@ void KeyedStoreGenericAssembler::EmitGenericPropertyStore(
       InvalidateValidityCellIfPrototype(receiver_map, bitfield2);
       Add<NameDictionary>(properties, p->name, p->value,
                           &add_dictionary_property_slow);
-      Return(p->value);
+      exit_point->Return(p->value);
 
       BIND(&add_dictionary_property_slow);
-      TailCallRuntime(Runtime::kAddDictionaryProperty, p->context, p->receiver,
-                      p->name, p->value);
+      exit_point->ReturnCallRuntime(Runtime::kAddDictionaryProperty, p->context,
+                                    p->receiver, p->name, p->value);
     }
   }
 
@@ -796,13 +805,17 @@ void KeyedStoreGenericAssembler::EmitGenericPropertyStore(
 
     Callable callable = CodeFactory::Call(isolate());
     CallJS(callable, p->context, setter, receiver, p->value);
-    Return(p->value);
+    exit_point->Return(p->value);
 
     BIND(&not_callable);
     {
       Label strict(this);
-      BranchIfStrictMode(p->vector, p->slot, &strict);
-      Return(p->value);
+      if (assume_strict_language_mode) {
+        Goto(&strict);
+      } else {
+        BranchIfStrictMode(p->vector, p->slot, &strict);
+        exit_point->Return(p->value);
+      }
 
       BIND(&strict);
       {
@@ -815,9 +828,12 @@ void KeyedStoreGenericAssembler::EmitGenericPropertyStore(
   BIND(&readonly);
   {
     Label strict(this);
-    BranchIfStrictMode(p->vector, p->slot, &strict);
-    Return(p->value);
-
+    if (assume_strict_language_mode) {
+      Goto(&strict);
+    } else {
+      BranchIfStrictMode(p->vector, p->slot, &strict);
+      exit_point->Return(p->value);
+    }
     BIND(&strict);
     {
       Node* type = Typeof(p->receiver);