Implemented the ctz Turbo Fan operator for x64.

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/compiler/machine-type.h"
 
@@ skipping 101 matching lines @@
     kFloat64Max = 1u << 2,
     kFloat64Min = 1u << 3,
     kFloat64RoundDown = 1u << 4,
     kFloat64RoundTruncate = 1u << 5,
     kFloat64RoundTiesAway = 1u << 6,
     kInt32DivIsSafe = 1u << 7,
     kUint32DivIsSafe = 1u << 8,
     kWord32ShiftIsSafe = 1u << 9,
     kWord32Ctz = 1u << 10,
     kWord32Popcnt = 1u << 11,
+    kWord64Ctz = 1u << 12,
     kAllOptionalOps = kFloat32Max | kFloat32Min | kFloat64Max | kFloat64Min |
                       kFloat64RoundDown | kFloat64RoundTruncate |
-                      kFloat64RoundTiesAway | kWord32Ctz | kWord32Popcnt
+                      kFloat64RoundTiesAway | kWord32Ctz | kWord32Popcnt |
+                      kWord64Ctz
   };
   typedef base::Flags<Flag, unsigned> Flags;
 
   explicit MachineOperatorBuilder(Zone* zone, MachineType word = kMachPtr,
                                   Flags supportedOperators = kNoFlags);
 
   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();
   const OptionalOperator Word32Popcnt();
   bool Word32ShiftIsSafe() const { return flags_ & kWord32ShiftIsSafe; }
 
   const Operator* Word64And();
   const Operator* Word64Or();
   const Operator* Word64Xor();
   const Operator* Word64Shl();
   const Operator* Word64Shr();
   const Operator* Word64Sar();
   const Operator* Word64Ror();
   const Operator* Word64Clz();
+  const OptionalOperator Word64Ctz();
   const Operator* Word64Equal();
 
   const Operator* Int32Add();
   const Operator* Int32AddWithOverflow();
   const Operator* Int32Sub();
   const Operator* Int32SubWithOverflow();
   const Operator* Int32Mul();
   const Operator* Int32MulHigh();
   const Operator* Int32Div();
   const Operator* Int32Mod();
@@ skipping 156 matching lines @@
 };
 
 
 DEFINE_OPERATORS_FOR_FLAGS(MachineOperatorBuilder::Flags)
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_MACHINE_OPERATOR_H_