[turbofan] Introduce dedicated NumberToBoolean operator.

src/compiler/simplified-operator.h

 // 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.
 
 #ifndef V8_COMPILER_SIMPLIFIED_OPERATOR_H_
 #define V8_COMPILER_SIMPLIFIED_OPERATOR_H_
 
 #include <iosfwd>
 
 #include "src/compiler/operator.h"
@@ skipping 240 matching lines @@
   const Operator* NumberMin();
   const Operator* NumberPow();
   const Operator* NumberRound();
   const Operator* NumberSign();
   const Operator* NumberSin();
   const Operator* NumberSinh();
   const Operator* NumberSqrt();
   const Operator* NumberTan();
   const Operator* NumberTanh();
   const Operator* NumberTrunc();
+  const Operator* NumberToBoolean();
   const Operator* NumberToInt32();
   const Operator* NumberToUint32();
 
   const Operator* NumberSilenceNaN();
 
   const Operator* SpeculativeNumberAdd(NumberOperationHint hint);
   const Operator* SpeculativeNumberSubtract(NumberOperationHint hint);
   const Operator* SpeculativeNumberMultiply(NumberOperationHint hint);
   const Operator* SpeculativeNumberDivide(NumberOperationHint hint);
   const Operator* SpeculativeNumberModulus(NumberOperationHint hint);
@@ skipping 108 matching lines @@
   Zone* const zone_;
 
   DISALLOW_COPY_AND_ASSIGN(SimplifiedOperatorBuilder);
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_SIMPLIFIED_OPERATOR_H_