1 //===-- ffsti2.c - Implement __ffsti2 -------------------------------------===//
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
7 //===----------------------------------------------------------------------===//
9 // This file implements __ffsti2 for the compiler_rt library.
11 //===----------------------------------------------------------------------===//
17 // Returns: the index of the least significant 1-bit in a, or
18 // the value zero if a is zero. The least significant bit is index one.
20 COMPILER_RT_ABI si_int __ffsti2(ti_int a) {
26 return __builtin_ctzll(x.s.high) + (1 + sizeof(di_int) * CHAR_BIT);
28 return __builtin_ctzll(x.s.low) + 1;
31 #endif // CRT_HAS_128BIT