[runtime] Store constructor function index on primitive maps.

src/arm64/builtins-arm64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "src/codegen.h"
 #include "src/debug/debug.h"
@@ skipping 418 matching lines @@
       Register unused_props = x10;
       Register inobject_props = x11;
       Register inst_sizes_or_attrs = x11;
       Register prealloc_fields = x10;
       __ Ldr(inst_sizes_or_attrs,
              FieldMemOperand(init_map, Map::kInstanceAttributesOffset));
       __ Ubfx(unused_props, inst_sizes_or_attrs,
               Map::kUnusedPropertyFieldsByte * kBitsPerByte, kBitsPerByte);
       __ Ldr(inst_sizes_or_attrs,
              FieldMemOperand(init_map, Map::kInstanceSizesOffset));
-      __ Ubfx(inobject_props, inst_sizes_or_attrs,
-              Map::kInObjectPropertiesByte * kBitsPerByte, kBitsPerByte);
+      __ Ubfx(
+          inobject_props, inst_sizes_or_attrs,
+          Map::kInObjectPropertiesOrConstructorFunctionIndexByte * kBitsPerByte,
+          kBitsPerByte);
       __ Sub(prealloc_fields, inobject_props, unused_props);
 
       // Calculate number of property fields in the object.
       Register prop_fields = x6;
       __ Sub(prop_fields, obj_size, JSObject::kHeaderSize / kPointerSize);
 
       if (!is_api_function) {
         Label no_inobject_slack_tracking;
 
         // Check if slack tracking is enabled.
@@ skipping 1476 matching lines @@
   }
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM