1214152Sed/* ===-- clzti2.c - Implement __clzti2 -------------------------------------===
2214152Sed *
3214152Sed *      	       The LLVM Compiler Infrastructure
4214152Sed *
5222656Sed * This file is dual licensed under the MIT and the University of Illinois Open
6222656Sed * Source Licenses. See LICENSE.TXT for details.
7214152Sed *
8214152Sed * ===----------------------------------------------------------------------===
9214152Sed *
10214152Sed * This file implements __clzti2 for the compiler_rt library.
11214152Sed *
12214152Sed * ===----------------------------------------------------------------------===
13214152Sed */
14214152Sed
15239138Sandrew#include "int_lib.h"
16239138Sandrew
17263763Sdim#ifdef CRT_HAS_128BIT
18214152Sed
19214152Sed/* Returns: the number of leading 0-bits */
20214152Sed
21214152Sed/* Precondition: a != 0 */
22214152Sed
23214152Sedsi_int
24214152Sed__clzti2(ti_int a)
25214152Sed{
26214152Sed    twords x;
27214152Sed    x.all = a;
28214152Sed    const di_int f = -(x.s.high == 0);
29214152Sed    return __builtin_clzll((x.s.high & ~f) | (x.s.low & f)) +
30214152Sed           ((si_int)f & ((si_int)(sizeof(di_int) * CHAR_BIT)));
31214152Sed}
32214152Sed
33263763Sdim#endif /* CRT_HAS_128BIT */
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