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 | |
21 | COMPILER_RT_ABI 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 | |