Mark some common operator with Property::kNoThrow.

src/compiler/operator.h

 // Copyright 2013 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_OPERATOR_H_
 #define V8_COMPILER_OPERATOR_H_
 
 #include <ostream>  // NOLINT(readability/streams)
 
 #include "src/base/flags.h"
@@ skipping 26 matching lines @@
     kNoProperties = 0,
     kReducible = 1 << 0,    // Participates in strength reduction.
     kCommutative = 1 << 1,  // OP(a, b) == OP(b, a) for all inputs.
     kAssociative = 1 << 2,  // OP(a, OP(b,c)) == OP(OP(a,b), c) for all inputs.
     kIdempotent = 1 << 3,   // OP(a); OP(a) == OP(a).
     kNoRead = 1 << 4,       // Has no scheduling dependency on Effects
     kNoWrite = 1 << 5,      // Does not modify any Effects and thereby
                             // create new scheduling dependencies.
     kNoThrow = 1 << 6,      // Can never generate an exception.
     kFoldable = kNoRead | kNoWrite,
+    kKontrol = kFoldable | kNoThrow,
     kEliminatable = kNoWrite | kNoThrow,
     kPure = kNoRead | kNoWrite | kNoThrow | kIdempotent
   };
   typedef base::Flags<Property, uint8_t> Properties;
 
   // Constructor.
   Operator(Opcode opcode, Properties properties, const char* mnemonic,
            size_t value_in, size_t effect_in, size_t control_in,
            size_t value_out, size_t effect_out, size_t control_out);
 
@@ skipping 129 matching lines @@
   return reinterpret_cast<const Operator1<double, base::bit_equal_to<double>,
                                           base::bit_hash<double>>*>(op)
       ->parameter();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_OPERATOR_H_