1//===-- A simple sign type --------------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#ifndef LLVM_LIBC_SRC___SUPPORT_SIGN_H
10#define LLVM_LIBC_SRC___SUPPORT_SIGN_H
11
12#include "src/__support/macros/attributes.h" // LIBC_INLINE, LIBC_INLINE_VAR
13
14namespace LIBC_NAMESPACE_DECL {
15
16// A type to interact with signed arithmetic types.
17struct Sign {
18 LIBC_INLINE constexpr bool is_pos() const { return !is_negative; }
19 LIBC_INLINE constexpr bool is_neg() const { return is_negative; }
20
21 LIBC_INLINE friend constexpr bool operator==(Sign a, Sign b) {
22 return a.is_negative == b.is_negative;
23 }
24
25 LIBC_INLINE friend constexpr bool operator!=(Sign a, Sign b) {
26 return !(a == b);
27 }
28
29 static const Sign POS;
30 static const Sign NEG;
31
32 LIBC_INLINE constexpr Sign negate() const { return Sign(!is_negative); }
33
34private:
35 LIBC_INLINE constexpr explicit Sign(bool is_negative)
36 : is_negative(is_negative) {}
37
38 bool is_negative;
39};
40
41LIBC_INLINE_VAR constexpr Sign Sign::NEG = Sign(true);
42LIBC_INLINE_VAR constexpr Sign Sign::POS = Sign(false);
43
44} // namespace LIBC_NAMESPACE_DECL
45#endif // LLVM_LIBC_SRC___SUPPORT_SIGN_H
46