CTZ instruction implemented as optional operator.

src/ia32/macro-assembler-ia32.h

 // Copyright 2012 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_IA32_MACRO_ASSEMBLER_IA32_H_
 #define V8_IA32_MACRO_ASSEMBLER_IA32_H_
 
 #include "src/assembler.h"
 #include "src/bailout-reason.h"
 #include "src/frames.h"
@@ skipping 836 matching lines @@
   // Non-SSE2 instructions.
   void Pextrd(Register dst, XMMRegister src, int8_t imm8);
   void Pinsrd(XMMRegister dst, Register src, int8_t imm8) {
     Pinsrd(dst, Operand(src), imm8);
   }
   void Pinsrd(XMMRegister dst, const Operand& src, int8_t imm8);
 
   void Lzcnt(Register dst, Register src) { Lzcnt(dst, Operand(src)); }
   void Lzcnt(Register dst, const Operand& src);
 
+  void Tzcnt(Register dst, Register src) { Tzcnt(dst, Operand(src)); }
+  void Tzcnt(Register dst, const Operand& src);
+
   // Emit call to the code we are currently generating.
   void CallSelf() {
     Handle<Code> self(reinterpret_cast<Code**>(CodeObject().location()));
     call(self, RelocInfo::CODE_TARGET);
   }
 
   // Move if the registers are not identical.
   void Move(Register target, Register source);
 
   // Move a constant into a destination using the most efficient encoding.
@@ skipping 259 matching lines @@
   masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_IA32_MACRO_ASSEMBLER_IA32_H_