[compiler] Set/Get the Map's inobject properties start non-atomically

The property kInObjectPropertiesStartOrConstructorFunctionIndexOffset
was set as relaxed due to races with the layout_descriptor
(https://chromium-review.googlesource.com/c/v8/v8/+/555210/). The
layout_descriptor was removed with the removal of double field unboxing.

We are able to turn those property's accessors into non-atomic ones
since they are set at construction time.

Bug: v8:7790
Change-Id: I25c53f0e00718cca72ba86f8475af9ecefb7ba3d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2843359
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74174}

src/compiler/heap-refs.cc

@@ -3109,7 +3109,7 @@ FieldIndex MapRef::GetFieldIndexFor(InternalIndex descriptor_index) const {
 }
 
 int MapRef::GetInObjectPropertyOffset(int i) const {
-  if (data_->should_access_heap()) {
+  if (data_->should_access_heap() || broker()->is_concurrent_inlining()) {
     return object()->GetInObjectPropertyOffset(i);
   }
   return (GetInObjectPropertiesStartInWords() + i) * kTaggedSize;
@@ -3699,7 +3699,7 @@ bool MapRef::IsInobjectSlackTrackingInProgress() const {
 }
 
 int MapRef::constructor_function_index() const {
-  IF_ACCESS_FROM_HEAP_C(GetConstructorFunctionIndex);
+  IF_ACCESS_FROM_HEAP_WITH_FLAG_C(GetConstructorFunctionIndex);
   CHECK(IsPrimitiveMap());
   return data()->AsMap()->constructor_function_index();
 }
@@ -3721,7 +3721,7 @@ bool MapRef::CanTransition() const {
 }
 
 int MapRef::GetInObjectPropertiesStartInWords() const {
-  IF_ACCESS_FROM_HEAP_C(GetInObjectPropertiesStartInWords);
+  IF_ACCESS_FROM_HEAP_WITH_FLAG_C(GetInObjectPropertiesStartInWords);
   return data()->AsMap()->in_object_properties_start_in_words();
 }
 

src/objects/map-inl.h

@@ -277,15 +277,14 @@ void Map::set_instance_size(int value) {
 }
 
 int Map::inobject_properties_start_or_constructor_function_index() const {
-  return RELAXED_READ_BYTE_FIELD(
-      *this, kInObjectPropertiesStartOrConstructorFunctionIndexOffset);
+  return ReadField<byte>(
+      kInObjectPropertiesStartOrConstructorFunctionIndexOffset);
 }
 
 void Map::set_inobject_properties_start_or_constructor_function_index(
     int value) {
   CHECK_LT(static_cast<unsigned>(value), 256);
-  RELAXED_WRITE_BYTE_FIELD(
-      *this, kInObjectPropertiesStartOrConstructorFunctionIndexOffset,
+  WriteField<byte>(kInObjectPropertiesStartOrConstructorFunctionIndexOffset,
                    static_cast<byte>(value));
 }