clang-tools  12.0.0git
ParsedAST.h
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1 //===--- ParsedAST.h - Building translation units ----------------*- 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 exposes building a file as if it were open in clangd, and defines
10 // the ParsedAST structure that holds the results.
11 //
12 // This is similar to a clang -fsyntax-only run that produces a clang AST, but
13 // we have several customizations:
14 // - preamble handling
15 // - capturing diagnostics for later access
16 // - running clang-tidy checks checks
17 //
18 //===----------------------------------------------------------------------===//
19 
20 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANGD_PARSEDAST_H
21 #define LLVM_CLANG_TOOLS_EXTRA_CLANGD_PARSEDAST_H
22 
23 #include "CollectMacros.h"
24 #include "Compiler.h"
25 #include "Diagnostics.h"
26 #include "Headers.h"
27 #include "Preamble.h"
29 #include "support/Path.h"
30 #include "clang/Frontend/FrontendAction.h"
31 #include "clang/Frontend/PrecompiledPreamble.h"
32 #include "clang/Lex/Preprocessor.h"
33 #include "clang/Tooling/CompilationDatabase.h"
34 #include "clang/Tooling/Syntax/Tokens.h"
35 #include "llvm/ADT/ArrayRef.h"
36 #include "llvm/ADT/None.h"
37 #include "llvm/ADT/Optional.h"
38 #include "llvm/ADT/StringRef.h"
39 #include <memory>
40 #include <string>
41 #include <vector>
42 
43 namespace clang {
44 namespace clangd {
45 class SymbolIndex;
46 
47 /// Stores and provides access to parsed AST.
48 class ParsedAST {
49 public:
50  /// Attempts to run Clang and store the parsed AST.
51  /// If \p Preamble is non-null it is reused during parsing.
52  /// This function does not check if preamble is valid to reuse.
53  static llvm::Optional<ParsedAST>
54  build(llvm::StringRef Filename, const ParseInputs &Inputs,
55  std::unique_ptr<clang::CompilerInvocation> CI,
56  llvm::ArrayRef<Diag> CompilerInvocationDiags,
57  std::shared_ptr<const PreambleData> Preamble);
58 
59  ParsedAST(ParsedAST &&Other);
60  ParsedAST &operator=(ParsedAST &&Other);
61 
62  ~ParsedAST();
63 
64  /// Note that the returned ast will not contain decls from the preamble that
65  /// were not deserialized during parsing. Clients should expect only decls
66  /// from the main file to be in the AST.
67  ASTContext &getASTContext();
68  const ASTContext &getASTContext() const;
69 
70  Preprocessor &getPreprocessor();
71  std::shared_ptr<Preprocessor> getPreprocessorPtr();
72  const Preprocessor &getPreprocessor() const;
73 
74  SourceManager &getSourceManager() {
75  return getASTContext().getSourceManager();
76  }
77  const SourceManager &getSourceManager() const {
78  return getASTContext().getSourceManager();
79  }
80 
81  const LangOptions &getLangOpts() const {
82  return getASTContext().getLangOpts();
83  }
84 
85  /// This function returns top-level decls present in the main file of the AST.
86  /// The result does not include the decls that come from the preamble.
87  /// (These should be const, but RecursiveASTVisitor requires Decl*).
88  ArrayRef<Decl *> getLocalTopLevelDecls();
89 
90  const std::vector<Diag> &getDiagnostics() const;
91 
92  /// Returns the estimated size of the AST and the accessory structures, in
93  /// bytes. Does not include the size of the preamble.
94  std::size_t getUsedBytes() const;
97 
98  /// Gets all macro references (definition, expansions) present in the main
99  /// file, including those in the preamble region.
100  const MainFileMacros &getMacros() const;
101  /// Tokens recorded while parsing the main file.
102  /// (!) does not have tokens from the preamble.
103  const syntax::TokenBuffer &getTokens() const { return Tokens; }
104 
105  /// Returns the version of the ParseInputs this AST was built from.
106  llvm::StringRef version() const { return Version; }
107 
108  /// Returns the version of the ParseInputs used to build Preamble part of this
109  /// AST. Might be None if no Preamble is used.
110  llvm::Optional<llvm::StringRef> preambleVersion() const;
111 
112 private:
113  ParsedAST(llvm::StringRef Version,
114  std::shared_ptr<const PreambleData> Preamble,
115  std::unique_ptr<CompilerInstance> Clang,
116  std::unique_ptr<FrontendAction> Action, syntax::TokenBuffer Tokens,
117  MainFileMacros Macros, std::vector<Decl *> LocalTopLevelDecls,
118  std::vector<Diag> Diags, IncludeStructure Includes,
119  CanonicalIncludes CanonIncludes);
120 
121  std::string Version;
122  // In-memory preambles must outlive the AST, it is important that this member
123  // goes before Clang and Action.
124  std::shared_ptr<const PreambleData> Preamble;
125  // We store an "incomplete" FrontendAction (i.e. no EndSourceFile was called
126  // on it) and CompilerInstance used to run it. That way we don't have to do
127  // complex memory management of all Clang structures on our own. (They are
128  // stored in CompilerInstance and cleaned up by
129  // FrontendAction.EndSourceFile).
130  std::unique_ptr<CompilerInstance> Clang;
131  std::unique_ptr<FrontendAction> Action;
132  /// Tokens recorded after the preamble finished.
133  /// - Includes all spelled tokens for the main file.
134  /// - Includes expanded tokens produced **after** preabmle.
135  /// - Does not have spelled or expanded tokens for files from preamble.
136  syntax::TokenBuffer Tokens;
137 
138  /// All macro definitions and expansions in the main file.
139  MainFileMacros Macros;
140  // Data, stored after parsing.
141  std::vector<Diag> Diags;
142  // Top-level decls inside the current file. Not that this does not include
143  // top-level decls from the preamble.
144  std::vector<Decl *> LocalTopLevelDecls;
145  IncludeStructure Includes;
146  CanonicalIncludes CanonIncludes;
147 };
148 
149 /// For testing/debugging purposes. Note that this method deserializes all
150 /// unserialized Decls, so use with care.
151 void dumpAST(ParsedAST &AST, llvm::raw_ostream &OS);
152 
153 } // namespace clangd
154 } // namespace clang
155 
156 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANGD_PARSEDAST_H
ParsedAST & operator=(ParsedAST &&Other)
const LangOptions & getLangOpts() const
Definition: ParsedAST.h:81
Preprocessor & getPreprocessor()
Definition: ParsedAST.cpp:477
void dumpAST(ParsedAST &AST, llvm::raw_ostream &OS)
For testing/debugging purposes.
Definition: ParsedAST.cpp:241
ParseInputs Inputs
ArrayRef< Decl * > getLocalTopLevelDecls()
This function returns top-level decls present in the main file of the AST.
Definition: ParsedAST.cpp:487
const syntax::TokenBuffer & getTokens() const
Tokens recorded while parsing the main file.
Definition: ParsedAST.h:103
ASTContext & getASTContext()
Note that the returned ast will not contain decls from the preamble that were not deserialized during...
Definition: ParsedAST.cpp:471
std::size_t getUsedBytes() const
Returns the estimated size of the AST and the accessory structures, in bytes.
Definition: ParsedAST.cpp:495
std::unique_ptr< CompilerInvocation > CI
Maps a definition location onto an #include file, based on a set of filename rules.
const CanonicalIncludes & getCanonicalIncludes() const
Definition: ParsedAST.cpp:531
const IncludeStructure & getIncludeStructure() const
Definition: ParsedAST.cpp:527
std::string Filename
Filename as a string.
const SourceManager & getSourceManager() const
Definition: ParsedAST.h:77
llvm::Optional< llvm::StringRef > preambleVersion() const
Returns the version of the ParseInputs used to build Preamble part of this AST.
Definition: ParsedAST.cpp:552
std::shared_ptr< Preprocessor > getPreprocessorPtr()
Definition: ParsedAST.cpp:479
llvm::raw_string_ostream OS
Definition: TraceTests.cpp:162
Stores and provides access to parsed AST.
Definition: ParsedAST.h:48
SourceManager & getSourceManager()
Definition: ParsedAST.h:74
const MainFileMacros & getMacros() const
Gets all macro references (definition, expansions) present in the main file, including those in the p...
Definition: ParsedAST.cpp:491
Information required to run clang, e.g. to parse AST or do code completion.
Definition: Compiler.h:47
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
llvm::StringRef version() const
Returns the version of the ParseInputs this AST was built from.
Definition: ParsedAST.h:106
static llvm::Optional< ParsedAST > build(llvm::StringRef Filename, const ParseInputs &Inputs, std::unique_ptr< clang::CompilerInvocation > CI, llvm::ArrayRef< Diag > CompilerInvocationDiags, std::shared_ptr< const PreambleData > Preamble)
Attempts to run Clang and store the parsed AST.
Definition: ParsedAST.cpp:246
ParsedAST(ParsedAST &&Other)
const std::vector< Diag > & getDiagnostics() const
Definition: ParsedAST.cpp:493