//===-- clzti2.c - Implement __clzti2 -------------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements __clzti2 for the compiler_rt library.
//
//===----------------------------------------------------------------------===//

#if __x86_64

#include "int_lib.h"

// Returns: the number of leading 0-bits

// Precondition: a != 0

si_int
__clzti2(ti_int a)
{
    twords x;
    x.all = a;
    const di_int f = -(x.high == 0);
    return __builtin_clzll((x.high & ~f) | (x.low & f)) +
           ((si_int)f & ((si_int)(sizeof(di_int) * CHAR_BIT)));
}

#endif