Array constructor expects AllocationSite or undefined as feedback.

src/x64/lithium-codegen-x64.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 3814 matching lines @@
 }
 
 
 void LCodeGen::DoCallNew(LCallNew* instr) {
   ASSERT(ToRegister(instr->context()).is(rsi));
   ASSERT(ToRegister(instr->constructor()).is(rdi));
   ASSERT(ToRegister(instr->result()).is(rax));
 
   __ Set(rax, instr->arity());
   // No cell in ebx for construct type feedback in optimized code
-  Handle<Object> megamorphic_symbol =
-      TypeFeedbackInfo::MegamorphicSentinel(isolate());
-  __ Move(rbx, megamorphic_symbol);
+  __ LoadRoot(rbx, Heap::kUndefinedValueRootIndex);
   CallConstructStub stub(NO_CALL_FUNCTION_FLAGS);
   CallCode(stub.GetCode(isolate()), RelocInfo::CONSTRUCT_CALL, instr);
 }
 
 
 void LCodeGen::DoCallNewArray(LCallNewArray* instr) {
   ASSERT(ToRegister(instr->context()).is(rsi));
   ASSERT(ToRegister(instr->constructor()).is(rdi));
   ASSERT(ToRegister(instr->result()).is(rax));
 
   __ Set(rax, instr->arity());
-  __ Move(rbx, TypeFeedbackInfo::MegamorphicSentinel(isolate()));
+  __ LoadRoot(rbx, Heap::kUndefinedValueRootIndex);
   ElementsKind kind = instr->hydrogen()->elements_kind();
   AllocationSiteOverrideMode override_mode =
       (AllocationSite::GetMode(kind) == TRACK_ALLOCATION_SITE)
           ? DISABLE_ALLOCATION_SITES
           : DONT_OVERRIDE;
 
   if (instr->arity() == 0) {
     ArrayNoArgumentConstructorStub stub(kind, override_mode);
     CallCode(stub.GetCode(isolate()), RelocInfo::CONSTRUCT_CALL, instr);
   } else if (instr->arity() == 1) {
@@ skipping 1782 matching lines @@
                                FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64