| 1 | //===-- A self contained equivalent of <algorithm> --------------*- 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 | // This file is minimalist on purpose but can receive a few more function if |
| 9 | // they prove useful. |
| 10 | //===----------------------------------------------------------------------===// |
| 11 | |
| 12 | #ifndef LLVM_LIBC_SRC___SUPPORT_CPP_ALGORITHM_H |
| 13 | #define LLVM_LIBC_SRC___SUPPORT_CPP_ALGORITHM_H |
| 14 | |
| 15 | #include "src/__support/macros/attributes.h" // LIBC_INLINE |
| 16 | #include "src/__support/macros/config.h" |
| 17 | |
| 18 | namespace LIBC_NAMESPACE_DECL { |
| 19 | namespace cpp { |
| 20 | |
| 21 | template <class T = void> struct plus {}; |
| 22 | template <class T = void> struct multiplies {}; |
| 23 | template <class T = void> struct bit_and {}; |
| 24 | template <class T = void> struct bit_or {}; |
| 25 | template <class T = void> struct bit_xor {}; |
| 26 | |
| 27 | template <class T> LIBC_INLINE constexpr const T &max(const T &a, const T &b) { |
| 28 | return (a < b) ? b : a; |
| 29 | } |
| 30 | |
| 31 | template <class T> LIBC_INLINE constexpr const T &min(const T &a, const T &b) { |
| 32 | return (a < b) ? a : b; |
| 33 | } |
| 34 | |
| 35 | template <class T> LIBC_INLINE constexpr T abs(T a) { return a < 0 ? -a : a; } |
| 36 | |
| 37 | template <class InputIt, class UnaryPred> |
| 38 | LIBC_INLINE constexpr InputIt find_if_not(InputIt first, InputIt last, |
| 39 | UnaryPred q) { |
| 40 | for (; first != last; ++first) |
| 41 | if (!q(*first)) |
| 42 | return first; |
| 43 | |
| 44 | return last; |
| 45 | } |
| 46 | |
| 47 | template <class InputIt, class UnaryPred> |
| 48 | LIBC_INLINE constexpr bool all_of(InputIt first, InputIt last, UnaryPred p) { |
| 49 | return find_if_not(first, last, p) == last; |
| 50 | } |
| 51 | |
| 52 | template <typename It, typename T, typename Comp> |
| 53 | LIBC_INLINE constexpr It lower_bound(It first, It last, const T &value, |
| 54 | Comp comp) { |
| 55 | auto count = last - first; |
| 56 | |
| 57 | while (count > 0) { |
| 58 | It it = first; |
| 59 | auto step = count / 2; |
| 60 | it += step; |
| 61 | |
| 62 | if (comp(*it, value)) { |
| 63 | first = ++it; |
| 64 | count -= step + 1; |
| 65 | } else { |
| 66 | count = step; |
| 67 | } |
| 68 | } |
| 69 | return first; |
| 70 | } |
| 71 | |
| 72 | } // namespace cpp |
| 73 | } // namespace LIBC_NAMESPACE_DECL |
| 74 | |
| 75 | #endif // LLVM_LIBC_SRC___SUPPORT_CPP_ALGORITHM_H |
| 76 | |