1 | //===- StmtIterator.h - Iterators for Statements ----------------*- 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 | // This file defines the StmtIterator and ConstStmtIterator classes. |
10 | // |
11 | //===----------------------------------------------------------------------===// |
12 | |
13 | #ifndef LLVM_CLANG_AST_STMTITERATOR_H |
14 | #define LLVM_CLANG_AST_STMTITERATOR_H |
15 | |
16 | #include <cassert> |
17 | #include <cstddef> |
18 | #include <cstdint> |
19 | #include <iterator> |
20 | |
21 | namespace clang { |
22 | |
23 | class Decl; |
24 | class Stmt; |
25 | class VariableArrayType; |
26 | |
27 | class StmtIteratorBase { |
28 | protected: |
29 | enum { |
30 | StmtMode = 0x0, |
31 | SizeOfTypeVAMode = 0x1, |
32 | DeclGroupMode = 0x2, |
33 | Flags = 0x3 |
34 | }; |
35 | |
36 | union { |
37 | Stmt **stmt; |
38 | Decl **DGI; |
39 | }; |
40 | uintptr_t RawVAPtr = 0; |
41 | Decl **DGE; |
42 | |
43 | StmtIteratorBase(Stmt **s) : stmt(s) {} |
44 | StmtIteratorBase(const VariableArrayType *t); |
45 | StmtIteratorBase(Decl **dgi, Decl **dge); |
46 | StmtIteratorBase() : stmt(nullptr) {} |
47 | |
48 | bool inDeclGroup() const { |
49 | return (RawVAPtr & Flags) == DeclGroupMode; |
50 | } |
51 | |
52 | bool inSizeOfTypeVA() const { |
53 | return (RawVAPtr & Flags) == SizeOfTypeVAMode; |
54 | } |
55 | |
56 | bool inStmt() const { |
57 | return (RawVAPtr & Flags) == StmtMode; |
58 | } |
59 | |
60 | const VariableArrayType *getVAPtr() const { |
61 | return reinterpret_cast<const VariableArrayType*>(RawVAPtr & ~Flags); |
62 | } |
63 | |
64 | void setVAPtr(const VariableArrayType *P) { |
65 | assert(inDeclGroup() || inSizeOfTypeVA()); |
66 | RawVAPtr = reinterpret_cast<uintptr_t>(P) | (RawVAPtr & Flags); |
67 | } |
68 | |
69 | void NextDecl(bool ImmediateAdvance = true); |
70 | bool HandleDecl(Decl* D); |
71 | void NextVA(); |
72 | |
73 | Stmt*& GetDeclExpr() const; |
74 | }; |
75 | |
76 | template <typename DERIVED, typename REFERENCE> |
77 | class StmtIteratorImpl : public StmtIteratorBase { |
78 | protected: |
79 | StmtIteratorImpl(const StmtIteratorBase& RHS) : StmtIteratorBase(RHS) {} |
80 | |
81 | public: |
82 | using iterator_category = std::forward_iterator_tag; |
83 | using value_type = REFERENCE; |
84 | using difference_type = std::ptrdiff_t; |
85 | using pointer = REFERENCE; |
86 | using reference = REFERENCE; |
87 | |
88 | StmtIteratorImpl() = default; |
89 | StmtIteratorImpl(Stmt **s) : StmtIteratorBase(s) {} |
90 | StmtIteratorImpl(Decl **dgi, Decl **dge) : StmtIteratorBase(dgi, dge) {} |
91 | StmtIteratorImpl(const VariableArrayType *t) : StmtIteratorBase(t) {} |
92 | |
93 | DERIVED& operator++() { |
94 | if (inStmt()) |
95 | ++stmt; |
96 | else if (getVAPtr()) |
97 | NextVA(); |
98 | else |
99 | NextDecl(); |
100 | |
101 | return static_cast<DERIVED&>(*this); |
102 | } |
103 | |
104 | DERIVED operator++(int) { |
105 | DERIVED tmp = static_cast<DERIVED&>(*this); |
106 | operator++(); |
107 | return tmp; |
108 | } |
109 | |
110 | friend bool operator==(const DERIVED &LHS, const DERIVED &RHS) { |
111 | return LHS.stmt == RHS.stmt && LHS.DGI == RHS.DGI && |
112 | LHS.RawVAPtr == RHS.RawVAPtr; |
113 | } |
114 | |
115 | friend bool operator!=(const DERIVED &LHS, const DERIVED &RHS) { |
116 | return !(LHS == RHS); |
117 | } |
118 | |
119 | REFERENCE operator*() const { |
120 | return inStmt() ? *stmt : GetDeclExpr(); |
121 | } |
122 | |
123 | REFERENCE operator->() const { return operator*(); } |
124 | }; |
125 | |
126 | struct ConstStmtIterator; |
127 | |
128 | struct StmtIterator : public StmtIteratorImpl<StmtIterator, Stmt*&> { |
129 | explicit StmtIterator() = default; |
130 | StmtIterator(Stmt** S) : StmtIteratorImpl<StmtIterator, Stmt*&>(S) {} |
131 | StmtIterator(Decl** dgi, Decl** dge) |
132 | : StmtIteratorImpl<StmtIterator, Stmt*&>(dgi, dge) {} |
133 | StmtIterator(const VariableArrayType *t) |
134 | : StmtIteratorImpl<StmtIterator, Stmt*&>(t) {} |
135 | |
136 | private: |
137 | StmtIterator(const StmtIteratorBase &RHS) |
138 | : StmtIteratorImpl<StmtIterator, Stmt *&>(RHS) {} |
139 | |
140 | inline friend StmtIterator |
141 | cast_away_const(const ConstStmtIterator &RHS); |
142 | }; |
143 | |
144 | struct ConstStmtIterator : public StmtIteratorImpl<ConstStmtIterator, |
145 | const Stmt*> { |
146 | explicit ConstStmtIterator() = default; |
147 | ConstStmtIterator(const StmtIterator& RHS) |
148 | : StmtIteratorImpl<ConstStmtIterator, const Stmt*>(RHS) {} |
149 | |
150 | ConstStmtIterator(Stmt * const *S) |
151 | : StmtIteratorImpl<ConstStmtIterator, const Stmt *>( |
152 | const_cast<Stmt **>(S)) {} |
153 | }; |
154 | |
155 | inline StmtIterator cast_away_const(const ConstStmtIterator &RHS) { |
156 | return RHS; |
157 | } |
158 | |
159 | } // namespace clang |
160 | |
161 | #endif // LLVM_CLANG_AST_STMTITERATOR_H |
162 | |