xref: /llvm-project/clang-tools-extra/clangd/index/Relation.h (revision 4d006520b8c0cc3a52913b4665bf741c737e5592)
1 //===--- Relation.h ----------------------------------------------*- 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_CLANG_TOOLS_EXTRA_CLANGD_INDEX_RELATION_H
10 #define LLVM_CLANG_TOOLS_EXTRA_CLANGD_INDEX_RELATION_H
11 
12 #include "index/SymbolID.h"
13 #include "llvm/ADT/iterator_range.h"
14 #include <cstdint>
15 #include <utility>
16 
17 namespace clang {
18 namespace clangd {
19 
20 enum class RelationKind : uint8_t {
21   BaseOf,
22   OverriddenBy,
23 };
24 
25 /// Represents a relation between two symbols.
26 /// For an example:
27 ///   - "A is a base class of B" is represented as
28 ///     { Subject = A, Predicate = BaseOf, Object = B }.
29 ///   - "Derived::Foo overrides Base::Foo" is represented as
30 ///     { Subject = Base::Foo, Predicate = OverriddenBy, Object = Derived::Foo
31 ///     }.
32 struct Relation {
33   SymbolID Subject;
34   RelationKind Predicate;
35   SymbolID Object;
36 
37   bool operator==(const Relation &Other) const {
38     return std::tie(Subject, Predicate, Object) ==
39            std::tie(Other.Subject, Other.Predicate, Other.Object);
40   }
41   // SPO order
42   bool operator<(const Relation &Other) const {
43     return std::tie(Subject, Predicate, Object) <
44            std::tie(Other.Subject, Other.Predicate, Other.Object);
45   }
46 };
47 llvm::raw_ostream &operator<<(llvm::raw_ostream &OS, const RelationKind R);
48 llvm::raw_ostream &operator<<(llvm::raw_ostream &OS, const Relation &R);
49 
50 class RelationSlab {
51 public:
52   using value_type = Relation;
53   using const_iterator = std::vector<value_type>::const_iterator;
54   using iterator = const_iterator;
55 
56   RelationSlab() = default;
57   RelationSlab(RelationSlab &&Slab) = default;
58   RelationSlab &operator=(RelationSlab &&RHS) = default;
59 
begin()60   const_iterator begin() const { return Relations.begin(); }
end()61   const_iterator end() const { return Relations.end(); }
size()62   size_t size() const { return Relations.size(); }
empty()63   bool empty() const { return Relations.empty(); }
64 
bytes()65   size_t bytes() const {
66     return sizeof(*this) + sizeof(value_type) * Relations.capacity();
67   }
68 
69   /// Lookup all relations matching the given subject and predicate.
70   llvm::iterator_range<iterator> lookup(const SymbolID &Subject,
71                                         RelationKind Predicate) const;
72 
73   /// RelationSlab::Builder is a mutable container that can 'freeze' to
74   /// RelationSlab.
75   class Builder {
76   public:
77     /// Adds a relation to the slab.
insert(const Relation & R)78     void insert(const Relation &R) { Relations.push_back(R); }
79 
80     /// Consumes the builder to finalize the slab.
81     RelationSlab build() &&;
82 
83   private:
84     std::vector<Relation> Relations;
85   };
86 
87 private:
RelationSlab(std::vector<Relation> Relations)88   RelationSlab(std::vector<Relation> Relations)
89       : Relations(std::move(Relations)) {}
90 
91   std::vector<Relation> Relations;
92 };
93 
94 } // namespace clangd
95 } // namespace clang
96 
97 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANGD_INDEX_RELATION_H
98