1 | //===- AttrVisitor.h - Visitor for Attr subclasses --------------*- 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 AttrVisitor interface. |
10 | // |
11 | //===----------------------------------------------------------------------===// |
12 | |
13 | #ifndef LLVM_CLANG_AST_ATTRVISITOR_H |
14 | #define LLVM_CLANG_AST_ATTRVISITOR_H |
15 | |
16 | #include "clang/AST/Attr.h" |
17 | |
18 | namespace clang { |
19 | |
20 | namespace attrvisitor { |
21 | |
22 | /// A simple visitor class that helps create attribute visitors. |
23 | template <template <typename> class Ptr, typename ImplClass, |
24 | typename RetTy = void, class... ParamTys> |
25 | class Base { |
26 | public: |
27 | #define PTR(CLASS) typename Ptr<CLASS>::type |
28 | #define DISPATCH(NAME) \ |
29 | return static_cast<ImplClass *>(this)->Visit##NAME(static_cast<PTR(NAME)>(A)) |
30 | |
31 | RetTy Visit(PTR(Attr) A) { |
32 | switch (A->getKind()) { |
33 | |
34 | #define ATTR(NAME) \ |
35 | case attr::NAME: \ |
36 | DISPATCH(NAME##Attr); |
37 | #include "clang/Basic/AttrList.inc" |
38 | } |
39 | llvm_unreachable("Attr that isn't part of AttrList.inc!" ); |
40 | } |
41 | |
42 | // If the implementation chooses not to implement a certain visit |
43 | // method, fall back to the parent. |
44 | #define ATTR(NAME) \ |
45 | RetTy Visit##NAME##Attr(PTR(NAME##Attr) A) { DISPATCH(Attr); } |
46 | #include "clang/Basic/AttrList.inc" |
47 | |
48 | RetTy VisitAttr(PTR(Attr)) { return RetTy(); } |
49 | |
50 | #undef PTR |
51 | #undef DISPATCH |
52 | }; |
53 | |
54 | } // namespace attrvisitor |
55 | |
56 | /// A simple visitor class that helps create attribute visitors. |
57 | /// |
58 | /// This class does not preserve constness of Attr pointers (see |
59 | /// also ConstAttrVisitor). |
60 | template <typename ImplClass, typename RetTy = void, typename... ParamTys> |
61 | class AttrVisitor : public attrvisitor::Base<std::add_pointer, ImplClass, RetTy, |
62 | ParamTys...> {}; |
63 | |
64 | /// A simple visitor class that helps create attribute visitors. |
65 | /// |
66 | /// This class preserves constness of Attr pointers (see also |
67 | /// AttrVisitor). |
68 | template <typename ImplClass, typename RetTy = void, typename... ParamTys> |
69 | class ConstAttrVisitor |
70 | : public attrvisitor::Base<llvm::make_const_ptr, ImplClass, RetTy, |
71 | ParamTys...> {}; |
72 | |
73 | } // namespace clang |
74 | |
75 | #endif // LLVM_CLANG_AST_ATTRVISITOR_H |
76 | |