Access double fields in C++ as uint64_t fields to preserve signaling bit of a NaN.

src/factory.cc

 // Copyright 2014 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/factory.h"
 
 #include "src/accessors.h"
 #include "src/allocation-site-scopes.h"
 #include "src/ast/ast.h"
 #include "src/base/bits.h"
@@ skipping 1290 matching lines @@
 
 Handle<Object> Factory::NewNumberFromUint(uint32_t value,
                                           PretenureFlag pretenure) {
   int32_t int32v = static_cast<int32_t>(value);
   if (int32v >= 0 && Smi::IsValid(int32v)) {
     return handle(Smi::FromInt(int32v), isolate());
   }
   return NewHeapNumber(FastUI2D(value), IMMUTABLE, pretenure);
 }
 
-
-Handle<HeapNumber> Factory::NewHeapNumber(double value,
-                                          MutableMode mode,
+Handle<HeapNumber> Factory::NewHeapNumber(MutableMode mode,
                                           PretenureFlag pretenure) {
-  CALL_HEAP_FUNCTION(
-      isolate(),
-      isolate()->heap()->AllocateHeapNumber(value, mode, pretenure),
-      HeapNumber);
+  CALL_HEAP_FUNCTION(isolate(),
+                     isolate()->heap()->AllocateHeapNumber(mode, pretenure),
+                     HeapNumber);
 }
 
-
 #define SIMD128_NEW_DEF(TYPE, Type, type, lane_count, lane_type)               \
   Handle<Type> Factory::New##Type(lane_type lanes[lane_count],                 \
                                   PretenureFlag pretenure) {                   \
     CALL_HEAP_FUNCTION(                                                        \
         isolate(), isolate()->heap()->Allocate##Type(lanes, pretenure), Type); \
   }
 SIMD128_TYPES(SIMD128_NEW_DEF)
 #undef SIMD128_NEW_DEF
 
 
@@ skipping 1514 matching lines @@
     Handle<AccessorInfo> prototype =
         Accessors::FunctionPrototypeInfo(isolate(), rw_attribs);
     Descriptor d = Descriptor::AccessorConstant(
         Handle<Name>(Name::cast(prototype->name())), prototype, rw_attribs);
     map->AppendDescriptor(&d);
   }
 }
 
 }  // namespace internal
 }  // namespace v8