[turbofan] Properly represent the float64 hole.

src/compiler/operation-typer.h

 // Copyright 2016 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_COMPILER_OPERATION_TYPER_H_
 #define V8_COMPILER_OPERATION_TYPER_H_
 
 #include "src/base/flags.h"
 #include "src/compiler/opcodes.h"
 
@@ skipping 30 matching lines @@
   SIMPLIFIED_NUMBER_UNOP_LIST(DECLARE_METHOD)
   SIMPLIFIED_SPECULATIVE_NUMBER_UNOP_LIST(DECLARE_METHOD)
 #undef DECLARE_METHOD
 
 // Number binary operators.
 #define DECLARE_METHOD(Name) Type* Name(Type* lhs, Type* rhs);
   SIMPLIFIED_NUMBER_BINOP_LIST(DECLARE_METHOD)
   SIMPLIFIED_SPECULATIVE_NUMBER_BINOP_LIST(DECLARE_METHOD)
 #undef DECLARE_METHOD
 
+  // Check operators.
+  Type* CheckFloat64Hole(Type* type);
+  Type* CheckNumber(Type* type);
+
   Type* TypeTypeGuard(const Operator* sigma_op, Type* input);
 
   enum ComparisonOutcomeFlags {
     kComparisonTrue = 1,
     kComparisonFalse = 2,
     kComparisonUndefined = 4
   };
 
   Type* singleton_false() const { return singleton_false_; }
   Type* singleton_true() const { return singleton_true_; }
@@ skipping 25 matching lines @@
   Type* singleton_the_hole_;
   Type* signed32ish_;
   Type* unsigned32ish_;
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_OPERATION_TYPER_H_