1*0b57cec5SDimitry Andric //===-- clzti2.c - Implement __clzti2 -------------------------------------===// 2*0b57cec5SDimitry Andric // 3*0b57cec5SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4*0b57cec5SDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 5*0b57cec5SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6*0b57cec5SDimitry Andric // 7*0b57cec5SDimitry Andric //===----------------------------------------------------------------------===// 8*0b57cec5SDimitry Andric // 9*0b57cec5SDimitry Andric // This file implements __clzti2 for the compiler_rt library. 10*0b57cec5SDimitry Andric // 11*0b57cec5SDimitry Andric //===----------------------------------------------------------------------===// 12*0b57cec5SDimitry Andric 13*0b57cec5SDimitry Andric #include "int_lib.h" 14*0b57cec5SDimitry Andric 15*0b57cec5SDimitry Andric #ifdef CRT_HAS_128BIT 16*0b57cec5SDimitry Andric 17*0b57cec5SDimitry Andric // Returns: the number of leading 0-bits 18*0b57cec5SDimitry Andric 19*0b57cec5SDimitry Andric // Precondition: a != 0 20*0b57cec5SDimitry Andric 21*0b57cec5SDimitry Andric COMPILER_RT_ABI si_int __clzti2(ti_int a) { 22*0b57cec5SDimitry Andric twords x; 23*0b57cec5SDimitry Andric x.all = a; 24*0b57cec5SDimitry Andric const di_int f = -(x.s.high == 0); 25*0b57cec5SDimitry Andric return __builtin_clzll((x.s.high & ~f) | (x.s.low & f)) + 26*0b57cec5SDimitry Andric ((si_int)f & ((si_int)(sizeof(di_int) * CHAR_BIT))); 27*0b57cec5SDimitry Andric } 28*0b57cec5SDimitry Andric 29*0b57cec5SDimitry Andric #endif // CRT_HAS_128BIT 30