xref: /freebsd/contrib/llvm-project/compiler-rt/lib/builtins/absvdi2.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
10b57cec5SDimitry Andric //===-- absvdi2.c - Implement __absvdi2 -----------------------------------===//
20b57cec5SDimitry Andric //
30b57cec5SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
40b57cec5SDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
50b57cec5SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
60b57cec5SDimitry Andric //
70b57cec5SDimitry Andric //===----------------------------------------------------------------------===//
80b57cec5SDimitry Andric //
90b57cec5SDimitry Andric // This file implements __absvdi2 for the compiler_rt library.
100b57cec5SDimitry Andric //
110b57cec5SDimitry Andric //===----------------------------------------------------------------------===//
120b57cec5SDimitry Andric 
130b57cec5SDimitry Andric #include "int_lib.h"
140b57cec5SDimitry Andric 
150b57cec5SDimitry Andric // Returns: absolute value
160b57cec5SDimitry Andric 
170b57cec5SDimitry Andric // Effects: aborts if abs(x) < 0
180b57cec5SDimitry Andric 
__absvdi2(di_int a)190b57cec5SDimitry Andric COMPILER_RT_ABI di_int __absvdi2(di_int a) {
200b57cec5SDimitry Andric   const int N = (int)(sizeof(di_int) * CHAR_BIT);
21*06c3fb27SDimitry Andric   if (a == ((di_int)((du_int)1 << (N - 1))))
220b57cec5SDimitry Andric     compilerrt_abort();
230b57cec5SDimitry Andric   const di_int t = a >> (N - 1);
240b57cec5SDimitry Andric   return (a ^ t) - t;
250b57cec5SDimitry Andric }
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