[turbofan] Don't treat the hole NaN as constant inside the compiler.

src/assembler.cc

Index: src/assembler.cc
diff --git a/src/assembler.cc b/src/assembler.cc
index f90a0a2ee5b7fe2292f0aeae5b0eb479f30d9796..50ff603e7e4e727da98e26a47ae9b7d39d204230 100644
--- a/src/assembler.cc
+++ b/src/assembler.cc
@@ -120,7 +120,7 @@ double min_int;
 double one_half;
 double minus_one_half;
 double negative_infinity;
-double the_hole_nan;
+uint64_t the_hole_nan;
 double uint32_bias;
 };
 
@@ -928,7 +928,7 @@ void ExternalReference::SetUp() {
   double_constants.min_int = kMinInt;
   double_constants.one_half = 0.5;
   double_constants.minus_one_half = -0.5;
-  double_constants.the_hole_nan = bit_cast<double>(kHoleNanInt64);
+  double_constants.the_hole_nan = kHoleNanInt64;
   double_constants.negative_infinity = -V8_INFINITY;
   double_constants.uint32_bias =
     static_cast<double>(static_cast<uint32_t>(0xFFFFFFFF)) + 1;