CTZ instruction implemented as optional operator.

src/ia32/assembler-ia32.cc

 // 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 1289 matching lines @@
 
 
 void Assembler::bsr(Register dst, const Operand& src) {
   EnsureSpace ensure_space(this);
   EMIT(0x0F);
   EMIT(0xBD);
   emit_operand(dst, src);
 }
 
 
+void Assembler::bsf(Register dst, const Operand& src) {
+  EnsureSpace ensure_space(this);
+  EMIT(0x0F);
+  EMIT(0xBC);
+  emit_operand(dst, src);
+}
+
+
 void Assembler::hlt() {
   EnsureSpace ensure_space(this);
   EMIT(0xF4);
 }
 
 
 void Assembler::int3() {
   EnsureSpace ensure_space(this);
   EMIT(0xCC);
 }
@@ skipping 1628 matching lines @@
     fflush(coverage_log);
   }
 }
 
 #endif
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_IA32