cosmopolitan/third_party/compiler_rt/ffssi2.c

33 lines
883 B
C

/* clang-format off */
/* ===-- ffssi2.c - Implement __ffssi2 -------------------------------------===
*
* 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 __ffssi2 for the compiler_rt library.
*
* ===----------------------------------------------------------------------===
*/
STATIC_YOINK("huge_compiler_rt_license");
#include "third_party/compiler_rt/int_lib.h"
/* 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.
*/
COMPILER_RT_ABI si_int
__ffssi2(si_int a)
{
if (a == 0)
{
return 0;
}
return __builtin_ctz(a) + 1;
}