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//===-- ctzti2.c - Implement __ctzti2 -------------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements __ctzti2 for the compiler_rt library.
//
//===----------------------------------------------------------------------===//

#if __x86_64

#include "int_lib.h"

// Returns: the number of trailing 0-bits

// Precondition: a != 0

si_int
__ctzti2(ti_int a)
{
    twords x;
    x.all = a;
    const di_int f = -(x.low == 0);
    return __builtin_ctzll((x.high & f) | (x.low & ~f)) +
              ((si_int)f & ((si_int)(sizeof(di_int) * CHAR_BIT)));
}

#endif