| //===-- clzti2.c - Implement __clzti2 -------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements __clzti2 for the compiler_rt library. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "int_lib.h" |
| |
| #ifdef CRT_HAS_128BIT |
| |
| // Returns: the number of leading 0-bits |
| |
| // Precondition: a != 0 |
| |
| COMPILER_RT_ABI int __clzti2(ti_int a) { |
| twords x; |
| x.all = a; |
| const di_int f = -(x.s.high == 0); |
| return __builtin_clzll((x.s.high & ~f) | (x.s.low & f)) + |
| ((si_int)f & ((si_int)(sizeof(di_int) * CHAR_BIT))); |
| } |
| |
| #endif // CRT_HAS_128BIT |
