llvm-project/compiler-rt/lib/absvdi2.c

30 lines
816 B
C

/*===-- absvdi2.c - Implement __absvdi2 -----------------------------------===
*
* The LLVM Compiler Infrastructure
*
* This file is dual licensed under the MIT and the University of Illinois Open
* Source Licenses. See LICENSE.TXT for details.
*
*===----------------------------------------------------------------------===
*
* 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;
}