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

30 lines
782 B
C

//===-- absvsi2.c - Implement __absvsi2 -----------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements __absvsi2 for the compiler_rt library.
//
//===----------------------------------------------------------------------===//
#include "int_lib.h"
#include <stdlib.h>
// Returns: absolute value
// Effects: aborts if abs(x) < 0
si_int
__absvsi2(si_int a)
{
const int N = (int)(sizeof(si_int) * CHAR_BIT);
if (a == (1 << (N-1)))
abort();
const si_int t = a >> (N - 1);
return (a ^ t) - t;
}