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/* ===-- ffsti2.c - Implement __ffsti2 -------------------------------------===
*
* The LLVM Compiler Infrastructure
*
* This file is dual licensed under the MIT and the University of Illinois Open
* Source Licenses. See LICENSE.TXT for details.
*
* ===----------------------------------------------------------------------===
*
* This file implements __ffsti2 for the compiler_rt library.
*
* ===----------------------------------------------------------------------===
*/
#include "int_lib.h"
#if __x86_64
/* Returns: the index of the least significant 1-bit in a, or
* the value zero if a is zero. The least significant bit is index one.
*/
si_int
__ffsti2(ti_int a)
{
twords x;
x.all = a;
if (x.s.low == 0)
{
if (x.s.high == 0)
return 0;
return __builtin_ctzll(x.s.high) + (1 + sizeof(di_int) * CHAR_BIT);
}
return __builtin_ctzll(x.s.low) + 1;
}
#endif /* __x86_64 */
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