minix/sys/external/bsd/compiler_rt/dist/lib/ctzdi2.c
Lionel Sambuc 4684ddb6aa LLVM Minix changes
- import libcxx
 - reduce targets to the one when compiled as a tools

Change-Id: Iabb8427f80ff8e89463559a28bcb8b4f2bdbc496
2014-07-28 17:05:59 +02:00

29 lines
836 B
C

/* ===-- ctzdi2.c - Implement __ctzdi2 -------------------------------------===
*
* 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 __ctzdi2 for the compiler_rt library.
*
* ===----------------------------------------------------------------------===
*/
#include "int_lib.h"
/* Returns: the number of trailing 0-bits */
/* Precondition: a != 0 */
COMPILER_RT_ABI si_int
__ctzdi2(di_int a)
{
dwords x;
x.all = a;
const si_int f = -(x.s.low == 0);
return __builtin_ctz((x.s.high & f) | (x.s.low & ~f)) +
(f & ((si_int)(sizeof(si_int) * CHAR_BIT)));
}