[turbofan] Add DebugBreak machine operator and support

src/compiler/machine-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_MACHINE_OPERATOR_H_
 #define V8_COMPILER_MACHINE_OPERATOR_H_
 
 #include "src/base/flags.h"
 #include "src/machine-type.h"
 
@@ skipping 110 matching lines @@
                       kWord32Ctz | kWord64Ctz | kWord32Popcnt | kWord64Popcnt |
                       kWord32ReverseBits | kWord64ReverseBits
   };
   typedef base::Flags<Flag, unsigned> Flags;
 
   explicit MachineOperatorBuilder(
       Zone* zone,
       MachineRepresentation word = MachineType::PointerRepresentation(),
       Flags supportedOperators = kNoFlags);
 
+  const Operator* DebugBreak();
+
   const Operator* Word32And();
   const Operator* Word32Or();
   const Operator* Word32Xor();
   const Operator* Word32Shl();
   const Operator* Word32Shr();
   const Operator* Word32Sar();
   const Operator* Word32Ror();
   const Operator* Word32Equal();
   const Operator* Word32Clz();
   const OptionalOperator Word32Ctz();
@@ skipping 411 matching lines @@
 };
 
 
 DEFINE_OPERATORS_FOR_FLAGS(MachineOperatorBuilder::Flags)
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_MACHINE_OPERATOR_H_