Use signaling NaN for holes in fixed double arrays.

src/x64/macro-assembler-x64.h

 // Copyright 2012 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.
 
 #ifndef V8_X64_MACRO_ASSEMBLER_X64_H_
 #define V8_X64_MACRO_ASSEMBLER_X64_H_
 
 #include "src/assembler.h"
 #include "src/bailout-reason.h"
 #include "src/frames.h"
@@ skipping 875 matching lines @@
   void Move(Register dst, Handle<Object> value, RelocInfo::Mode rmode) {
     AllowDeferredHandleDereference using_raw_address;
     DCHECK(!RelocInfo::IsNone(rmode));
     DCHECK(value->IsHeapObject());
     DCHECK(!isolate()->heap()->InNewSpace(*value));
     movp(dst, reinterpret_cast<void*>(value.location()), rmode);
   }
 
   void Move(XMMRegister dst, uint32_t src);
   void Move(XMMRegister dst, uint64_t src);
+  void Move(XMMRegister dst, float src) { Move(dst, bit_cast<uint32_t>(src)); }
+  void Move(XMMRegister dst, double src) { Move(dst, bit_cast<uint64_t>(src)); }
 
   // Control Flow
   void Jump(Address destination, RelocInfo::Mode rmode);
   void Jump(ExternalReference ext);
   void Jump(const Operand& op);
   void Jump(Handle<Code> code_object, RelocInfo::Mode rmode);
 
   void Call(Address destination, RelocInfo::Mode rmode);
   void Call(ExternalReference ext);
   void Call(const Operand& op);
@@ skipping 722 matching lines @@
     masm->popfq();                                                           \
   }                                                                          \
   masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 } }  // namespace v8::internal
 
 #endif  // V8_X64_MACRO_ASSEMBLER_X64_H_