1156cd587Sjoerg /* ===-- clzti2.c - Implement __clzti2 -------------------------------------=== 2156cd587Sjoerg * 3156cd587Sjoerg * The LLVM Compiler Infrastructure 4156cd587Sjoerg * 5156cd587Sjoerg * This file is dual licensed under the MIT and the University of Illinois Open 6156cd587Sjoerg * Source Licenses. See LICENSE.TXT for details. 7156cd587Sjoerg * 8156cd587Sjoerg * ===----------------------------------------------------------------------=== 9156cd587Sjoerg * 10156cd587Sjoerg * This file implements __clzti2 for the compiler_rt library. 11156cd587Sjoerg * 12156cd587Sjoerg * ===----------------------------------------------------------------------=== 13156cd587Sjoerg */ 14156cd587Sjoerg 15156cd587Sjoerg #include "int_lib.h" 16156cd587Sjoerg 17156cd587Sjoerg #ifdef CRT_HAS_128BIT 18156cd587Sjoerg 19156cd587Sjoerg /* Returns: the number of leading 0-bits */ 20156cd587Sjoerg 21156cd587Sjoerg /* Precondition: a != 0 */ 22156cd587Sjoerg 23*f7f78b33Sjoerg COMPILER_RT_ABI si_int __clzti2(ti_int a)24156cd587Sjoerg__clzti2(ti_int a) 25156cd587Sjoerg { 26156cd587Sjoerg twords x; 27156cd587Sjoerg x.all = a; 28156cd587Sjoerg const di_int f = -(x.s.high == 0); 29156cd587Sjoerg return __builtin_clzll((x.s.high & ~f) | (x.s.low & f)) + 30156cd587Sjoerg ((si_int)f & ((si_int)(sizeof(di_int) * CHAR_BIT))); 31156cd587Sjoerg } 32156cd587Sjoerg 33156cd587Sjoerg #endif /* CRT_HAS_128BIT */ 34