1//===-- ctzti2.c - Implement __ctzti2 -------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements __ctzti2 for the compiler_rt library.
10//
11//===----------------------------------------------------------------------===//
12
13#include "int_lib.h"
14
15#ifdef CRT_HAS_128BIT
16
17// Returns: the number of trailing 0-bits
18
19// Precondition: a != 0
20
21COMPILER_RT_ABI si_int __ctzti2(ti_int a) {
22  twords x;
23  x.all = a;
24  const di_int f = -(x.s.low == 0);
25  return __builtin_ctzll((x.s.high & f) | (x.s.low & ~f)) +
26         ((si_int)f & ((si_int)(sizeof(di_int) * CHAR_BIT)));
27}
28
29#endif // CRT_HAS_128BIT
30