1//===--- LocateSymbol.cpp - Find locations providing a symbol -------------===//
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#include "AnalysisInternal.h"
10#include "clang-include-cleaner/Types.h"
11#include "clang/AST/Decl.h"
12#include "clang/AST/DeclBase.h"
13#include "clang/AST/DeclCXX.h"
14#include "clang/AST/DeclTemplate.h"
15#include "clang/Tooling/Inclusions/StandardLibrary.h"
16#include "llvm/Support/Casting.h"
17#include <utility>
18#include <vector>
19
20namespace clang::include_cleaner {
21namespace {
22
23template <typename T> Hints completeIfDefinition(T *D) {
24 return D->isThisDeclarationADefinition() ? Hints::CompleteSymbol
25 : Hints::None;
26}
27
28Hints declHints(const Decl *D) {
29 // Definition is only needed for classes and templates for completeness.
30 if (auto *TD = llvm::dyn_cast<TagDecl>(Val: D))
31 return completeIfDefinition(D: TD);
32 else if (auto *CTD = llvm::dyn_cast<ClassTemplateDecl>(Val: D))
33 return completeIfDefinition(D: CTD);
34 else if (auto *FTD = llvm::dyn_cast<FunctionTemplateDecl>(Val: D))
35 return completeIfDefinition(D: FTD);
36 // Any other declaration is assumed usable.
37 return Hints::CompleteSymbol;
38}
39
40std::vector<Hinted<SymbolLocation>> locateDecl(const Decl &D) {
41 std::vector<Hinted<SymbolLocation>> Result;
42 // FIXME: Should we also provide physical locations?
43 if (auto SS = tooling::stdlib::Recognizer()(&D))
44 return {{*SS, Hints::CompleteSymbol}};
45 // FIXME: Signal foreign decls, e.g. a forward declaration not owned by a
46 // library. Some useful signals could be derived by checking the DeclContext.
47 // Most incidental forward decls look like:
48 // namespace clang {
49 // class SourceManager; // likely an incidental forward decl.
50 // namespace my_own_ns {}
51 // }
52 for (auto *Redecl : D.redecls())
53 Result.push_back(x: {Redecl->getLocation(), declHints(D: Redecl)});
54 return Result;
55}
56
57std::vector<Hinted<SymbolLocation>> locateMacro(const Macro &M,
58 const tooling::stdlib::Lang L) {
59 // FIXME: Should we also provide physical locations?
60 if (auto SS = tooling::stdlib::Symbol::named(Scope: "", Name: M.Name->getName(), Language: L))
61 return {{*SS, Hints::CompleteSymbol}};
62 return {{M.Definition, Hints::CompleteSymbol}};
63}
64} // namespace
65
66std::vector<Hinted<SymbolLocation>> locateSymbol(const Symbol &S,
67 const LangOptions &LO) {
68 const auto L = !LO.CPlusPlus && LO.C99 ? tooling::stdlib::Lang::C
69 : tooling::stdlib::Lang::CXX;
70 switch (S.kind()) {
71 case Symbol::Declaration:
72 return locateDecl(D: S.declaration());
73 case Symbol::Macro:
74 return locateMacro(M: S.macro(), L);
75 }
76 llvm_unreachable("Unknown Symbol::Kind enum");
77}
78
79} // namespace clang::include_cleaner
80

source code of clang-tools-extra/include-cleaner/lib/LocateSymbol.cpp