Symbols for type cells.

src/x64/builtins-x64.cc

 // Copyright 2012 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 515 matching lines @@
     __ movp(kScratchRegister, Operand(rbx, rcx, times_pointer_size, 0));
     __ push(Operand(kScratchRegister, 0));  // dereference handle
     __ addq(rcx, Immediate(1));
     __ bind(&entry);
     __ cmpq(rcx, rax);
     __ j(not_equal, &loop);
 
     // Invoke the code.
     if (is_construct) {
       // No type feedback cell is available
-      Handle<Object> undefined_sentinel(
-          masm->isolate()->factory()->undefined_value());
-      __ Move(rbx, undefined_sentinel);
+      Handle<Object> megamorphic_sentinel =
+          TypeFeedbackInfo::MegamorphicSentinel(masm->isolate());
+      __ Move(rbx, megamorphic_sentinel);
       // Expects rdi to hold function pointer.
       CallConstructStub stub(NO_CALL_FUNCTION_FLAGS);
       __ CallStub(&stub);
     } else {
       ParameterCount actual(rax);
       // Function must be in rdi.
       __ InvokeFunction(rdi, actual, CALL_FUNCTION, NullCallWrapper());
     }
     // Exit the internal frame. Notice that this also removes the empty
     // context and the function left on the stack by the code
@@ skipping 572 matching lines @@
     // Will both indicate a NULL and a Smi.
     STATIC_ASSERT(kSmiTag == 0);
     Condition not_smi = NegateCondition(masm->CheckSmi(rbx));
     __ Check(not_smi, kUnexpectedInitialMapForArrayFunction);
     __ CmpObjectType(rbx, MAP_TYPE, rcx);
     __ Check(equal, kUnexpectedInitialMapForArrayFunction);
   }
 
   // Run the native code for the Array function called as a normal function.
   // tail call a stub
-  Handle<Object> undefined_sentinel(
-      masm->isolate()->heap()->undefined_value(),
-      masm->isolate());
-  __ Move(rbx, undefined_sentinel);
+  Handle<Object> megamorphic_sentinel =
+      TypeFeedbackInfo::MegamorphicSentinel(masm->isolate());
+  __ Move(rbx, megamorphic_sentinel);
   ArrayConstructorStub stub(masm->isolate());
   __ TailCallStub(&stub);
 }
 
 
 void Builtins::Generate_StringConstructCode(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- rax                 : number of arguments
   //  -- rdi                 : constructor function
   //  -- rsp[0]              : return address
@@ skipping 289 matching lines @@
   __ bind(&ok);
   __ ret(0);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64