Array constructor expects AllocationSite or undefined as feedback.

src/a64/builtins-a64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 131 matching lines @@
   if (FLAG_debug_code) {
     // Initial map for the builtin Array functions should be maps.
     __ Ldr(x10, FieldMemOperand(x1, JSFunction::kPrototypeOrInitialMapOffset));
     __ Tst(x10, kSmiTagMask);
     __ Assert(ne, kUnexpectedInitialMapForArrayFunction);
     __ CompareObjectType(x10, x11, x12, MAP_TYPE);
     __ Assert(eq, kUnexpectedInitialMapForArrayFunction);
   }
 
   // Run the native code for the Array function called as a normal function.
-  Handle<Object> megamorphic_sentinel =
-      TypeFeedbackInfo::MegamorphicSentinel(masm->isolate());
-  __ Mov(x2, Operand(megamorphic_sentinel));
+  __ LoadRoot(x2, Heap::kUndefinedValueRootIndex);
   ArrayConstructorStub stub(masm->isolate());
   __ TailCallStub(&stub);
 }
 
 
 void Builtins::Generate_StringConstructCode(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- x0                     : number of arguments
   //  -- x1                     : constructor function
   //  -- lr                     : return address
@@ skipping 556 matching lines @@
     __ Mov(x25, x19);
     // Don't initialize the reserved registers.
     // x26 : root register (root).
     // x27 : context pointer (cp).
     // x28 : JS stack pointer (jssp).
     // x29 : frame pointer (fp).
 
     __ Mov(x0, argc);
     if (is_construct) {
       // No type feedback cell is available.
-      Handle<Object> megamorphic_sentinel =
-          TypeFeedbackInfo::MegamorphicSentinel(masm->isolate());
-      __ Mov(x2, Operand(megamorphic_sentinel));
+      __ LoadRoot(x2, Heap::kUndefinedValueRootIndex);
 
       CallConstructStub stub(NO_CALL_FUNCTION_FLAGS);
       __ CallStub(&stub);
     } else {
       ParameterCount actual(x0);
       __ InvokeFunction(function, actual, CALL_FUNCTION, NullCallWrapper());
     }
     // Exit the JS internal frame and remove the parameters (except function),
     // and return.
   }
@@ skipping 756 matching lines @@
   __ Bind(&dont_adapt_arguments);
   __ Jump(code_entry);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM