xref: /freebsd/contrib/llvm-project/compiler-rt/lib/orc/interval_set.h (revision 1d386b48a555f61cb7325543adbbb5c3f3407a66)
1 //===--------- interval_set.h - A sorted interval set -----------*- 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 // Implements a coalescing interval set.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef ORC_RT_INTERVAL_SET_H
14 #define ORC_RT_INTERVAL_SET_H
15 
16 #include "interval_map.h"
17 
18 namespace __orc_rt {
19 
20 /// Implements a coalescing interval set.
21 ///
22 /// Adjacent intervals are coalesced.
23 ///
24 /// NOTE: The interface is kept mostly compatible with LLVM's IntervalMap
25 ///       collection to make it easy to swap over in the future if we choose
26 ///       to.
27 template <typename KeyT, IntervalCoalescing Coalescing>
28 class IntervalSet {
29 private:
30   using ImplMap = IntervalMap<KeyT, std::monostate, Coalescing>;
31 public:
32 
33   using value_type = std::pair<KeyT, KeyT>;
34 
35   class const_iterator {
36     friend class IntervalSet;
37   public:
38     using difference_type = typename ImplMap::iterator::difference_type;
39     using value_type = IntervalSet::value_type;
40     using pointer = const value_type *;
41     using reference = const value_type &;
42     using iterator_category = std::input_iterator_tag;
43 
44     const_iterator() = default;
45     const value_type &operator*() const { return I->first; }
46     const value_type *operator->() const { return &I->first; }
47     const_iterator &operator++() { ++I; return *this; }
48     const_iterator operator++(int) { auto Tmp = I; ++I; return Tmp; }
49     friend bool operator==(const const_iterator &LHS,
50                            const const_iterator &RHS) {
51       return LHS.I == RHS.I;
52     }
53     friend bool operator!=(const const_iterator &LHS,
54                            const const_iterator &RHS) {
55       return LHS.I != RHS.I;
56     }
57   private:
58     const_iterator(typename ImplMap::const_iterator I) : I(std::move(I)) {}
59     typename ImplMap::const_iterator I;
60   };
61 
62   bool empty() const { return Map.empty(); }
63 
64   void clear() { Map.clear(); }
65 
66   const_iterator begin() const { return const_iterator(Map.begin()); }
67   const_iterator end() const { return const_iterator(Map.end()); }
68 
69   const_iterator find(KeyT K) const {
70     return const_iterator(Map.find(K));
71   }
72 
73   void insert(KeyT KS, KeyT KE) {
74     Map.insert(std::move(KS), std::move(KE), std::monostate());
75   }
76 
77   void erase(KeyT KS, KeyT KE) {
78     Map.erase(KS, KE);
79   }
80 
81 private:
82   ImplMap Map;
83 };
84 
85 } // End namespace __orc_rt
86 
87 #endif // ORC_RT_INTERVAL_SET_H
88