lib/builtins/absvdi2.c

/*===-- absvdi2.c - Implement __absvdi2 -----------------------------------===
 *
 * 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 __absvdi2 for the compiler_rt library.
 *
 *===----------------------------------------------------------------------===
 */

#include "int_lib.h"

/* Returns: absolute value */

/* Effects: aborts if abs(x) < 0 */

COMPILER_RT_ABI di_int
__absvdi2(di_int a)
{
    const int N = (int)(sizeof(di_int) * CHAR_BIT);
    if (a == ((di_int)1 << (N-1)))
        compilerrt_abort();
    const di_int t = a >> (N - 1);
    return (a ^ t) - t;
}