1 /* ===-- absvsi2.c - Implement __absvsi2 -----------------------------------===
2 *
3 * The LLVM Compiler Infrastructure
4 *
5 * This file is dual licensed under the MIT and the University of Illinois Open
6 * Source Licenses. See LICENSE.TXT for details.
7 *
8 * ===----------------------------------------------------------------------===
9 *
10 * This file implements __absvsi2 for the compiler_rt library.
11 *
12 * ===----------------------------------------------------------------------===
13 */
14
15 #include "int_lib.h"
16
17 /* Returns: absolute value */
18
19 /* Effects: aborts if abs(x) < 0 */
20
21 COMPILER_RT_ABI si_int
__absvsi2(si_int a)22 __absvsi2(si_int a)
23 {
24 const int N = (int)(sizeof(si_int) * CHAR_BIT);
25 if (a == (1 << (N-1)))
26 compilerrt_abort();
27 const si_int t = a >> (N - 1);
28 return (a ^ t) - t;
29 }
30