1//===-- clzti2.c - Implement __clzti2 -------------------------------------===// 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 __clzti2 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 leading 0-bits 18 19// Precondition: a != 0 20 21COMPILER_RT_ABI si_int __clzti2(ti_int a) { 22 twords x; 23 x.all = a; 24 const di_int f = -(x.s.high == 0); 25 return __builtin_clzll((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