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/* ===-- clzti2.c - Implement __clzti2 -------------------------------------===
*
* 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 __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.s.high == 0);
return __builtin_clzll((x.s.high & ~f) | (x.s.low & f)) +
((si_int)f & ((si_int)(sizeof(di_int) * CHAR_BIT)));
}
#endif /* __x86_64 */
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