CTZ instruction implemented as optional operator.

src/ia32/assembler-ia32.h

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // All Rights Reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 // - Redistributions of source code must retain the above copyright notice,
 // this list of conditions and the following disclaimer.
 //
@@ skipping 761 matching lines @@
   void xor_(const Operand& dst, Register src);
   void xor_(Register dst, const Immediate& imm) { xor_(Operand(dst), imm); }
   void xor_(const Operand& dst, const Immediate& x);
 
   // Bit operations.
   void bt(const Operand& dst, Register src);
   void bts(Register dst, Register src) { bts(Operand(dst), src); }
   void bts(const Operand& dst, Register src);
   void bsr(Register dst, Register src) { bsr(dst, Operand(src)); }
   void bsr(Register dst, const Operand& src);
+  void bsf(Register dst, Register src) { bsf(dst, Operand(src)); }
+  void bsf(Register dst, const Operand& src);
 
   // Miscellaneous
   void hlt();
   void int3();
   void nop();
   void ret(int imm16);
   void ud2();
 
   // Label operations & relative jumps (PPUM Appendix D)
   //
@@ skipping 772 matching lines @@
   Assembler* assembler_;
 #ifdef DEBUG
   int space_before_;
 #endif
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_IA32_ASSEMBLER_IA32_H_