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