llvm-project/compiler-rt/lib/builtins/absvsi2.c

29 lines
824 B
C

/* ===-- absvsi2.c - Implement __absvsi2 -----------------------------------===
*
* Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
* See https://llvm.org/LICENSE.txt for license information.
* SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
*
* ===----------------------------------------------------------------------===
*
* This file implements __absvsi2 for the compiler_rt library.
*
* ===----------------------------------------------------------------------===
*/
#include "int_lib.h"
/* Returns: absolute value */
/* Effects: aborts if abs(x) < 0 */
COMPILER_RT_ABI si_int
__absvsi2(si_int a)
{
const int N = (int)(sizeof(si_int) * CHAR_BIT);
if (a == (1 << (N-1)))
compilerrt_abort();
const si_int t = a >> (N - 1);
return (a ^ t) - t;
}