[csa] Use high-level DescriptorArray accessors.

This fixes places that assume that DescriptorArray is a WeakFixedArray.

In addition to the existing:
 - LoadDetailsByKeyIndex
 - LoadValueByKeyIndex
 - LoadFieldTypeByKeyIndex
This introduces Load*ByDescriptorEntry versions and LoadKeyByKeyIndex.

Bug: v8:8486
Change-Id: I958867138df7756c715ae3d449b3206a32076514
Reviewed-on: https://chromium-review.googlesource.com/c/1346501
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57727}

src/builtins/builtins-function-gen.cc

@@ -60,24 +60,23 @@ TF_BUILTIN(FastFunctionPrototypeBind, CodeStubAssembler) {
   Comment("Check name and length properties");
   {
     const int length_index = JSFunction::kLengthDescriptorIndex;
-    TNode<Name> maybe_length = CAST(LoadWeakFixedArrayElement(
-        descriptors, DescriptorArray::ToKeyIndex(length_index)));
+    TNode<Name> maybe_length =
+        LoadKeyByDescriptorEntry(descriptors, length_index);
     GotoIf(WordNotEqual(maybe_length, LoadRoot(RootIndex::klength_string)),
            &slow);
 
-    TNode<Object> maybe_length_accessor = CAST(LoadWeakFixedArrayElement(
-        descriptors, DescriptorArray::ToValueIndex(length_index)));
+    TNode<Object> maybe_length_accessor =
+        LoadValueByDescriptorEntry(descriptors, length_index);
     GotoIf(TaggedIsSmi(maybe_length_accessor), &slow);
     Node* length_value_map = LoadMap(CAST(maybe_length_accessor));
     GotoIfNot(IsAccessorInfoMap(length_value_map), &slow);
 
     const int name_index = JSFunction::kNameDescriptorIndex;
-    TNode<Name> maybe_name = CAST(LoadWeakFixedArrayElement(
-        descriptors, DescriptorArray::ToKeyIndex(name_index)));
+    TNode<Name> maybe_name = LoadKeyByDescriptorEntry(descriptors, name_index);
     GotoIf(WordNotEqual(maybe_name, LoadRoot(RootIndex::kname_string)), &slow);
 
-    TNode<Object> maybe_name_accessor = CAST(LoadWeakFixedArrayElement(
-        descriptors, DescriptorArray::ToValueIndex(name_index)));
+    TNode<Object> maybe_name_accessor =
+        LoadValueByDescriptorEntry(descriptors, name_index);
     GotoIf(TaggedIsSmi(maybe_name_accessor), &slow);
     TNode<Map> name_value_map = LoadMap(CAST(maybe_name_accessor));
     GotoIfNot(IsAccessorInfoMap(name_value_map), &slow);

src/builtins/builtins-object-gen.cc

@@ -318,15 +318,15 @@ TNode<JSArray> ObjectEntriesValuesBuiltinsAssembler::FastGetOwnValuesOrEntries(
       // Currently, we will not invoke getters,
       // so, map will not be changed.
       CSA_ASSERT(this, WordEqual(map, LoadMap(object)));
-      TNode<Uint32T> descriptor_index = TNode<Uint32T>::UncheckedCast(
-          TruncateIntPtrToInt32(var_descriptor_number.value()));
-      Node* next_key = GetKey(descriptors, descriptor_index);
+      TNode<IntPtrT> descriptor_entry = var_descriptor_number.value();
+      Node* next_key = LoadKeyByDescriptorEntry(descriptors, descriptor_entry);
 
       // Skip Symbols.
       GotoIf(IsSymbol(next_key), &next_descriptor);
 
-      TNode<Uint32T> details = TNode<Uint32T>::UncheckedCast(
-          DescriptorArrayGetDetails(descriptors, descriptor_index));
+      TNode<Uint32T> details =
+          LoadDetailsByDescriptorEntry(descriptors, descriptor_entry);
+
       TNode<Uint32T> kind = LoadPropertyKind(details);
 
       // If property is accessor, we escape fast path and call runtime.

src/code-stub-assembler.cc

@@ -2902,14 +2902,14 @@ void CodeStubAssembler::EnsureArrayLengthWritable(TNode<Map> map,
 
   int length_index = JSArray::kLengthDescriptorIndex;
 #ifdef DEBUG
-  TNode<Name> maybe_length = CAST(LoadWeakFixedArrayElement(
-      descriptors, DescriptorArray::ToKeyIndex(length_index)));
+  TNode<Name> maybe_length =
+      LoadKeyByDescriptorEntry(descriptors, length_index);
   CSA_ASSERT(this,
              WordEqual(maybe_length, LoadRoot(RootIndex::klength_string)));
 #endif
 
-  TNode<Uint32T> details = LoadDetailsByKeyIndex(
-      descriptors, IntPtrConstant(DescriptorArray::ToKeyIndex(length_index)));
+  TNode<Uint32T> details =
+      LoadDetailsByDescriptorEntry(descriptors, length_index);
   GotoIf(IsSetWord32(details, PropertyDetails::kAttributesReadOnlyMask),
          bailout);
 }
@@ -8230,30 +8230,81 @@ TNode<IntPtrT> CodeStubAssembler::EntryToIndex(TNode<IntPtrT> entry,
                                                field_index));
 }
 
+TNode<Name> CodeStubAssembler::LoadKeyByKeyIndex(
+    TNode<DescriptorArray> container, TNode<IntPtrT> key_index) {
+  return CAST(LoadWeakFixedArrayElement(container, key_index, 0));
+}
+
 TNode<Uint32T> CodeStubAssembler::LoadDetailsByKeyIndex(
     TNode<DescriptorArray> container, TNode<IntPtrT> key_index) {
-  const int kKeyToDetailsOffset =
-      (DescriptorArray::kEntryDetailsIndex - DescriptorArray::kEntryKeyIndex) *
-      kPointerSize;
+  const int kKeyToDetails =
+      DescriptorArray::ToDetailsIndex(0) - DescriptorArray::ToKeyIndex(0);
   return Unsigned(LoadAndUntagToWord32ArrayElement(
-      container, WeakFixedArray::kHeaderSize, key_index, kKeyToDetailsOffset));
+      container, WeakFixedArray::kHeaderSize, key_index,
+      kKeyToDetails * kPointerSize));
 }
 
 TNode<Object> CodeStubAssembler::LoadValueByKeyIndex(
     TNode<DescriptorArray> container, TNode<IntPtrT> key_index) {
-  const int kKeyToValueOffset =
-      (DescriptorArray::kEntryValueIndex - DescriptorArray::kEntryKeyIndex) *
-      kPointerSize;
-  return CAST(
-      LoadWeakFixedArrayElement(container, key_index, kKeyToValueOffset));
+  const int kKeyToValue =
+      DescriptorArray::ToValueIndex(0) - DescriptorArray::ToKeyIndex(0);
+  return CAST(LoadWeakFixedArrayElement(container, key_index,
+                                        kKeyToValue * kPointerSize));
 }
 
 TNode<MaybeObject> CodeStubAssembler::LoadFieldTypeByKeyIndex(
     TNode<DescriptorArray> container, TNode<IntPtrT> key_index) {
-  const int kKeyToValueOffset =
-      (DescriptorArray::kEntryValueIndex - DescriptorArray::kEntryKeyIndex) *
-      kPointerSize;
-  return LoadWeakFixedArrayElement(container, key_index, kKeyToValueOffset);
+  const int kKeyToValue =
+      DescriptorArray::ToValueIndex(0) - DescriptorArray::ToKeyIndex(0);
+  return LoadWeakFixedArrayElement(container, key_index,
+                                   kKeyToValue * kPointerSize);
+}
+
+TNode<IntPtrT> CodeStubAssembler::DescriptorEntryToIndex(
+    TNode<IntPtrT> descriptor_entry) {
+  return IntPtrMul(descriptor_entry,
+                   IntPtrConstant(DescriptorArray::kEntrySize));
+}
+
+TNode<Name> CodeStubAssembler::LoadKeyByDescriptorEntry(
+    TNode<DescriptorArray> container, TNode<IntPtrT> descriptor_entry) {
+  return CAST(LoadWeakFixedArrayElement(
+      container, DescriptorEntryToIndex(descriptor_entry),
+      DescriptorArray::ToKeyIndex(0) * kPointerSize));
+}
+
+TNode<Name> CodeStubAssembler::LoadKeyByDescriptorEntry(
+    TNode<DescriptorArray> container, int descriptor_entry) {
+  return CAST(LoadWeakFixedArrayElement(
+      container, DescriptorArray::ToKeyIndex(descriptor_entry)));
+}
+
+TNode<Uint32T> CodeStubAssembler::LoadDetailsByDescriptorEntry(
+    TNode<DescriptorArray> container, TNode<IntPtrT> descriptor_entry) {
+  return Unsigned(LoadAndUntagToWord32ArrayElement(
+      container, WeakFixedArray::kHeaderSize,
+      DescriptorEntryToIndex(descriptor_entry),
+      DescriptorArray::ToDetailsIndex(0) * kPointerSize));
+}
+
+TNode<Uint32T> CodeStubAssembler::LoadDetailsByDescriptorEntry(
+    TNode<DescriptorArray> container, int descriptor_entry) {
+  return Unsigned(LoadAndUntagToWord32ArrayElement(
+      container, WeakFixedArray::kHeaderSize, IntPtrConstant(0),
+      DescriptorArray::ToDetailsIndex(descriptor_entry) * kPointerSize));
+}
+
+TNode<Object> CodeStubAssembler::LoadValueByDescriptorEntry(
+    TNode<DescriptorArray> container, int descriptor_entry) {
+  return CAST(LoadWeakFixedArrayElement(
+      container, DescriptorArray::ToValueIndex(descriptor_entry)));
+}
+
+TNode<MaybeObject> CodeStubAssembler::LoadFieldTypeByDescriptorEntry(
+    TNode<DescriptorArray> container, TNode<IntPtrT> descriptor_entry) {
+  return LoadWeakFixedArrayElement(
+      container, DescriptorEntryToIndex(descriptor_entry),
+      DescriptorArray::ToValueIndex(0) * kPointerSize);
 }
 
 template TNode<IntPtrT> CodeStubAssembler::EntryToIndex<NameDictionary>(
@@ -8809,18 +8860,13 @@ void CodeStubAssembler::LookupBinary(TNode<Name> unique_name,
 void CodeStubAssembler::DescriptorArrayForEach(
     VariableList& variable_list, TNode<Uint32T> start_descriptor,
     TNode<Uint32T> end_descriptor, const ForEachDescriptorBodyFunction& body) {
-  TNode<IntPtrT> start_index =
-      IntPtrAdd(IntPtrConstant(DescriptorArray::ToKeyIndex(0)),
-                EntryIndexToIndex<DescriptorArray>(start_descriptor));
-
-  TNode<IntPtrT> end_index =
-      IntPtrAdd(IntPtrConstant(DescriptorArray::ToKeyIndex(0)),
-                EntryIndexToIndex<DescriptorArray>(end_descriptor));
+  TNode<IntPtrT> start_index = ToKeyIndex<DescriptorArray>(start_descriptor);
+  TNode<IntPtrT> end_index = ToKeyIndex<DescriptorArray>(end_descriptor);
 
   BuildFastLoop(variable_list, start_index, end_index,
                 [=](Node* index) {
-                  TNode<UintPtrT> descriptor_key_index =
-                      TNode<UintPtrT>::UncheckedCast(index);
+                  TNode<IntPtrT> descriptor_key_index =
+                      TNode<IntPtrT>::UncheckedCast(index);
                   body(descriptor_key_index);
                 },
                 DescriptorArray::kEntrySize, INTPTR_PARAMETERS,
@@ -8842,9 +8888,9 @@ void CodeStubAssembler::ForEachEnumerableOwnProperty(
 
   DescriptorArrayForEach(
       list, Unsigned(Int32Constant(0)), nof_descriptors,
-      [=, &var_stable](TNode<UintPtrT> descriptor_key_index) {
+      [=, &var_stable](TNode<IntPtrT> descriptor_key_index) {
         TNode<Name> next_key =
-            CAST(LoadWeakFixedArrayElement(descriptors, descriptor_key_index));
+            LoadKeyByKeyIndex(descriptors, descriptor_key_index);
 
         TVARIABLE(Object, var_value, SmiConstant(0));
         Label callback(this), next_iteration(this);
@@ -13644,9 +13690,8 @@ void CodeStubAssembler::GotoIfInitialPrototypePropertiesModified(
       // Assert that the name is correct. This essentially checks that
       // the descriptor index corresponds to the insertion order in
       // the bootstrapper.
-      CSA_ASSERT(this, WordEqual(LoadWeakFixedArrayElement(
-                                     descriptors,
-                                     DescriptorArray::ToKeyIndex(descriptor)),
+      CSA_ASSERT(this,
+                 WordEqual(LoadKeyByDescriptorEntry(descriptors, descriptor),
                            LoadRoot(properties[i].name_root_index)));
 
       TNode<Uint32T> details =

src/code-stub-assembler.h

@@ -2474,13 +2474,6 @@ class V8_EXPORT_PRIVATE CodeStubAssembler
     return LoadFixedArrayElement(CAST(container), key_index, kKeyToValueOffset);
   }
 
-  TNode<Uint32T> LoadDetailsByKeyIndex(TNode<DescriptorArray> container,
-                                       TNode<IntPtrT> key_index);
-  TNode<Object> LoadValueByKeyIndex(TNode<DescriptorArray> container,
-                                    TNode<IntPtrT> key_index);
-  TNode<MaybeObject> LoadFieldTypeByKeyIndex(TNode<DescriptorArray> container,
-                                             TNode<IntPtrT> key_index);
-
   // Stores the details for the entry with the given key_index.
   // |details| must be a Smi.
   template <class ContainerType>
@@ -3209,7 +3202,7 @@ class V8_EXPORT_PRIVATE CodeStubAssembler
   TNode<Uint32T> DescriptorArrayGetDetails(TNode<DescriptorArray> descriptors,
                                            TNode<Uint32T> descriptor_number);
 
-  typedef std::function<void(TNode<UintPtrT> descriptor_key_index)>
+  typedef std::function<void(TNode<IntPtrT> descriptor_key_index)>
       ForEachDescriptorBodyFunction;
 
   void DescriptorArrayForEach(VariableList& variable_list,
@@ -3217,6 +3210,33 @@ class V8_EXPORT_PRIVATE CodeStubAssembler
                               TNode<Uint32T> end_descriptor,
                               const ForEachDescriptorBodyFunction& body);
 
+  // Descriptor array accessors based on key_index, which is equal to
+  // DescriptorArray::ToKeyIndex(descriptor).
+  TNode<Name> LoadKeyByKeyIndex(TNode<DescriptorArray> container,
+                                TNode<IntPtrT> key_index);
+  TNode<Uint32T> LoadDetailsByKeyIndex(TNode<DescriptorArray> container,
+                                       TNode<IntPtrT> key_index);
+  TNode<Object> LoadValueByKeyIndex(TNode<DescriptorArray> container,
+                                    TNode<IntPtrT> key_index);
+  TNode<MaybeObject> LoadFieldTypeByKeyIndex(TNode<DescriptorArray> container,
+                                             TNode<IntPtrT> key_index);
+
+  TNode<IntPtrT> DescriptorEntryToIndex(TNode<IntPtrT> descriptor);
+
+  // Descriptor array accessors based on descriptor.
+  TNode<Name> LoadKeyByDescriptorEntry(TNode<DescriptorArray> descriptors,
+                                       TNode<IntPtrT> descriptor);
+  TNode<Name> LoadKeyByDescriptorEntry(TNode<DescriptorArray> descriptors,
+                                       int descriptor);
+  TNode<Uint32T> LoadDetailsByDescriptorEntry(
+      TNode<DescriptorArray> descriptors, TNode<IntPtrT> descriptor);
+  TNode<Uint32T> LoadDetailsByDescriptorEntry(
+      TNode<DescriptorArray> descriptors, int descriptor);
+  TNode<Object> LoadValueByDescriptorEntry(TNode<DescriptorArray> descriptors,
+                                           int descriptor);
+  TNode<MaybeObject> LoadFieldTypeByDescriptorEntry(
+      TNode<DescriptorArray> descriptors, TNode<IntPtrT> descriptor);
+
   typedef std::function<void(TNode<Name> key, TNode<Object> value)>
       ForEachKeyValueFunction;
 

src/ic/accessor-assembler.cc

@@ -215,7 +215,8 @@ void AccessorAssembler::HandleLoadCallbackProperty(const LoadICParameters* p,
                                                    TNode<WordT> handler_word,
                                                    ExitPoint* exit_point) {
   Comment("native_data_property_load");
-  Node* descriptor = DecodeWord<LoadHandler::DescriptorBits>(handler_word);
+  TNode<IntPtrT> descriptor =
+      Signed(DecodeWord<LoadHandler::DescriptorBits>(handler_word));
 
   Label runtime(this, Label::kDeferred);
   Callable callable = CodeFactory::ApiGetter(isolate());
@@ -325,22 +326,15 @@ void AccessorAssembler::HandleLoadField(Node* holder, Node* handler_word,
   }
 }
 
-TNode<Object> AccessorAssembler::LoadDescriptorValue(TNode<Map> map,
-                                                     Node* descriptor) {
-  return CAST(LoadDescriptorValueOrFieldType(map, descriptor));
+TNode<Object> AccessorAssembler::LoadDescriptorValue(
+    TNode<Map> map, TNode<IntPtrT> descriptor_entry) {
+  return CAST(LoadDescriptorValueOrFieldType(map, descriptor_entry));
 }
 
 TNode<MaybeObject> AccessorAssembler::LoadDescriptorValueOrFieldType(
-    TNode<Map> map, SloppyTNode<IntPtrT> descriptor) {
+    TNode<Map> map, TNode<IntPtrT> descriptor_entry) {
   TNode<DescriptorArray> descriptors = LoadMapDescriptors(map);
-  TNode<IntPtrT> scaled_descriptor =
-      IntPtrMul(descriptor, IntPtrConstant(DescriptorArray::kEntrySize));
-  TNode<IntPtrT> value_index = IntPtrAdd(
-      scaled_descriptor, IntPtrConstant(DescriptorArray::kFirstIndex +
-                                        DescriptorArray::kEntryValueIndex));
-  CSA_ASSERT(this, UintPtrLessThan(descriptor, LoadAndUntagWeakFixedArrayLength(
-                                                   descriptors)));
-  return LoadWeakFixedArrayElement(descriptors, value_index);
+  return LoadFieldTypeByDescriptorEntry(descriptors, descriptor_entry);
 }
 
 void AccessorAssembler::HandleLoadICSmiHandlerCase(
@@ -497,7 +491,8 @@ void AccessorAssembler::HandleLoadICSmiHandlerCase(
   BIND(&constant);
   {
     Comment("constant_load");
-    Node* descriptor = DecodeWord<LoadHandler::DescriptorBits>(handler_word);
+    TNode<IntPtrT> descriptor =
+        Signed(DecodeWord<LoadHandler::DescriptorBits>(handler_word));
     Node* value = LoadDescriptorValue(LoadMap(holder), descriptor);
 
     exit_point->Return(value);
@@ -526,7 +521,8 @@ void AccessorAssembler::HandleLoadICSmiHandlerCase(
   BIND(&accessor);
   {
     Comment("accessor_load");
-    Node* descriptor = DecodeWord<LoadHandler::DescriptorBits>(handler_word);
+    TNode<IntPtrT> descriptor =
+        Signed(DecodeWord<LoadHandler::DescriptorBits>(handler_word));
     Node* accessor_pair = LoadDescriptorValue(LoadMap(holder), descriptor);
     CSA_ASSERT(this, IsAccessorPair(accessor_pair));
     Node* getter = LoadObjectField(accessor_pair, AccessorPair::kGetterOffset);
@@ -827,7 +823,8 @@ void AccessorAssembler::JumpIfDataProperty(Node* details, Label* writable,
 void AccessorAssembler::HandleStoreICNativeDataProperty(
     const StoreICParameters* p, Node* holder, Node* handler_word) {
   Comment("native_data_property_store");
-  Node* descriptor = DecodeWord<StoreHandler::DescriptorBits>(handler_word);
+  TNode<IntPtrT> descriptor =
+      Signed(DecodeWord<StoreHandler::DescriptorBits>(handler_word));
   Node* accessor_info = LoadDescriptorValue(LoadMap(holder), descriptor);
   CSA_CHECK(this, IsAccessorInfo(accessor_info));
 
@@ -986,12 +983,10 @@ void AccessorAssembler::HandleStoreICTransitionMapHandlerCase(
   TNode<IntPtrT> last_key_index = UncheckedCast<IntPtrT>(IntPtrAdd(
       IntPtrConstant(DescriptorArray::ToKeyIndex(-1)), IntPtrMul(nof, factor)));
   if (flags & kValidateTransitionHandler) {
-    Node* key = LoadWeakFixedArrayElement(descriptors, last_key_index);
+    TNode<Name> key = LoadKeyByKeyIndex(descriptors, last_key_index);
     GotoIf(WordNotEqual(key, p->name), miss);
   } else {
-    CSA_ASSERT(this,
-               WordEqual(BitcastMaybeObjectToWord(LoadWeakFixedArrayElement(
-                             descriptors, last_key_index)),
+    CSA_ASSERT(this, WordEqual(LoadKeyByKeyIndex(descriptors, last_key_index),
                                p->name));
   }
   Node* details = LoadDetailsByKeyIndex(descriptors, last_key_index);
@@ -1254,7 +1249,8 @@ void AccessorAssembler::CheckPrototypeValidityCell(Node* maybe_validity_cell,
 void AccessorAssembler::HandleStoreAccessor(const StoreICParameters* p,
                                             Node* holder, Node* handler_word) {
   Comment("accessor_store");
-  Node* descriptor = DecodeWord<StoreHandler::DescriptorBits>(handler_word);
+  TNode<IntPtrT> descriptor =
+      Signed(DecodeWord<StoreHandler::DescriptorBits>(handler_word));
   Node* accessor_pair = LoadDescriptorValue(LoadMap(holder), descriptor);
   CSA_ASSERT(this, IsAccessorPair(accessor_pair));
   Node* setter = LoadObjectField(accessor_pair, AccessorPair::kSetterOffset);
@@ -1585,7 +1581,8 @@ Node* AccessorAssembler::PrepareValueForStore(Node* handler_word, Node* holder,
                        IntPtrConstant(StoreHandler::kConstField)),
              &done);
     }
-    Node* descriptor = DecodeWord<StoreHandler::DescriptorBits>(handler_word);
+    TNode<IntPtrT> descriptor =
+        Signed(DecodeWord<StoreHandler::DescriptorBits>(handler_word));
     TNode<MaybeObject> maybe_field_type =
         LoadDescriptorValueOrFieldType(LoadMap(holder), descriptor);
 

src/ic/accessor-assembler.h

@@ -148,9 +148,10 @@ class AccessorAssembler : public CodeStubAssembler {
                          TVariable<MaybeObject>* var_handler, Label* if_handler,
                          Label* miss, ExitPoint* exit_point);
 
-  TNode<Object> LoadDescriptorValue(TNode<Map> map, Node* descriptor);
+  TNode<Object> LoadDescriptorValue(TNode<Map> map,
+                                    TNode<IntPtrT> descriptor_entry);
   TNode<MaybeObject> LoadDescriptorValueOrFieldType(
-      TNode<Map> map, SloppyTNode<IntPtrT> descriptor);
+      TNode<Map> map, TNode<IntPtrT> descriptor_entry);
 
   void LoadIC_Uninitialized(const LoadICParameters* p);
 

src/ic/keyed-store-generic.cc

@@ -312,8 +312,7 @@ void KeyedStoreGenericAssembler::StoreElementWithCapacity(
     // The length property is non-configurable, so it's guaranteed to always
     // be the first property.
     TNode<DescriptorArray> descriptors = LoadMapDescriptors(receiver_map);
-    TNode<Uint32T> details = LoadDetailsByKeyIndex(
-        descriptors, IntPtrConstant(DescriptorArray::ToKeyIndex(0)));
+    TNode<Uint32T> details = LoadDetailsByDescriptorEntry(descriptors, 0);
     GotoIf(IsSetWord32(details, PropertyDetails::kAttributesReadOnlyMask),
            slow);
   }