[turbofan] Prevent storing signalling NaNs into holey double arrays.

src/compiler/machine-operator.h

Index: src/compiler/machine-operator.h
diff --git a/src/compiler/machine-operator.h b/src/compiler/machine-operator.h
index a199fd51824eef4c0096879b9cd9a6c47716eefd..9b1e8e8780b2bb4f53877e5ac06bd9602b35fbb2 100644
--- a/src/compiler/machine-operator.h
+++ b/src/compiler/machine-operator.h
@@ -382,6 +382,10 @@ class MachineOperatorBuilder final : public ZoneObject {
   const Operator* Float64InsertLowWord32();
   const Operator* Float64InsertHighWord32();
 
+  // Change signalling NaN to quiet NaN.
+  // Identity for any input that is not signalling NaN.
+  const Operator* Float64SilenceNaN();
+
   // SIMD operators.
   const Operator* CreateFloat32x4();
   const Operator* Float32x4ExtractLane();