clang-tools  10.0.0
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 
21 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANGD_PARSEDAST_H
22 #define LLVM_CLANG_TOOLS_EXTRA_CLANGD_PARSEDAST_H
23 
24 #include "CollectMacros.h"
25 #include "Compiler.h"
26 #include "Diagnostics.h"
27 #include "Headers.h"
28 #include "Path.h"
29 #include "Preamble.h"
31 #include "clang/Frontend/FrontendAction.h"
32 #include "clang/Frontend/PrecompiledPreamble.h"
33 #include "clang/Lex/Preprocessor.h"
34 #include "clang/Tooling/CompilationDatabase.h"
35 #include "clang/Tooling/Syntax/Tokens.h"
36 #include "llvm/ADT/ArrayRef.h"
37 #include <memory>
38 #include <string>
39 #include <vector>
40 
41 namespace clang {
42 namespace clangd {
43 class SymbolIndex;
44 
45 /// Stores and provides access to parsed AST.
46 class ParsedAST {
47 public:
48  /// Attempts to run Clang and store parsed AST. If \p Preamble is non-null
49  /// it is reused during parsing.
50  static llvm::Optional<ParsedAST>
51  build(std::unique_ptr<clang::CompilerInvocation> CI,
52  llvm::ArrayRef<Diag> CompilerInvocationDiags,
53  std::shared_ptr<const PreambleData> Preamble,
54  std::unique_ptr<llvm::MemoryBuffer> Buffer,
55  llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS,
56  const SymbolIndex *Index, const ParseOptions &Opts);
57 
58  ParsedAST(ParsedAST &&Other);
59  ParsedAST &operator=(ParsedAST &&Other);
60 
61  ~ParsedAST();
62 
63  /// Note that the returned ast will not contain decls from the preamble that
64  /// were not deserialized during parsing. Clients should expect only decls
65  /// from the main file to be in the AST.
66  ASTContext &getASTContext();
67  const ASTContext &getASTContext() const;
68 
69  Preprocessor &getPreprocessor();
70  std::shared_ptr<Preprocessor> getPreprocessorPtr();
71  const Preprocessor &getPreprocessor() const;
72 
73  SourceManager &getSourceManager() {
74  return getASTContext().getSourceManager();
75  }
76  const SourceManager &getSourceManager() const {
77  return getASTContext().getSourceManager();
78  }
79 
80  const LangOptions &getLangOpts() const {
81  return getASTContext().getLangOpts();
82  }
83 
84  /// This function returns top-level decls present in the main file of the AST.
85  /// The result does not include the decls that come from the preamble.
86  /// (These should be const, but RecursiveASTVisitor requires Decl*).
87  ArrayRef<Decl *> getLocalTopLevelDecls();
88 
89  const std::vector<Diag> &getDiagnostics() const;
90 
91  /// Returns the estimated size of the AST and the accessory structures, in
92  /// bytes. Does not include the size of the preamble.
93  std::size_t getUsedBytes() const;
96 
97  /// Gets all macro references (definition, expansions) present in the main
98  /// file, including those in the preamble region.
99  const MainFileMacros &getMacros() const;
100  /// Tokens recorded while parsing the main file.
101  /// (!) does not have tokens from the preamble.
102  const syntax::TokenBuffer &getTokens() const { return Tokens; }
103 
104 private:
105  ParsedAST(std::shared_ptr<const PreambleData> Preamble,
106  std::unique_ptr<CompilerInstance> Clang,
107  std::unique_ptr<FrontendAction> Action, syntax::TokenBuffer Tokens,
108  MainFileMacros Macros, std::vector<Decl *> LocalTopLevelDecls,
109  std::vector<Diag> Diags, IncludeStructure Includes,
110  CanonicalIncludes CanonIncludes);
111 
112  // In-memory preambles must outlive the AST, it is important that this member
113  // goes before Clang and Action.
114  std::shared_ptr<const PreambleData> Preamble;
115  // We store an "incomplete" FrontendAction (i.e. no EndSourceFile was called
116  // on it) and CompilerInstance used to run it. That way we don't have to do
117  // complex memory management of all Clang structures on our own. (They are
118  // stored in CompilerInstance and cleaned up by
119  // FrontendAction.EndSourceFile).
120  std::unique_ptr<CompilerInstance> Clang;
121  std::unique_ptr<FrontendAction> Action;
122  /// Tokens recorded after the preamble finished.
123  /// - Includes all spelled tokens for the main file.
124  /// - Includes expanded tokens produced **after** preabmle.
125  /// - Does not have spelled or expanded tokens for files from preamble.
126  syntax::TokenBuffer Tokens;
127 
128  /// All macro definitions and expansions in the main file.
129  MainFileMacros Macros;
130  // Data, stored after parsing.
131  std::vector<Diag> Diags;
132  // Top-level decls inside the current file. Not that this does not include
133  // top-level decls from the preamble.
134  std::vector<Decl *> LocalTopLevelDecls;
135  IncludeStructure Includes;
136  CanonicalIncludes CanonIncludes;
137 };
138 
139 /// Build an AST from provided user inputs. This function does not check if
140 /// preamble can be reused, as this function expects that \p Preamble is the
141 /// result of calling buildPreamble.
142 llvm::Optional<ParsedAST>
143 buildAST(PathRef FileName, std::unique_ptr<CompilerInvocation> Invocation,
144  llvm::ArrayRef<Diag> CompilerInvocationDiags,
145  const ParseInputs &Inputs,
146  std::shared_ptr<const PreambleData> Preamble);
147 
148 /// For testing/debugging purposes. Note that this method deserializes all
149 /// unserialized Decls, so use with care.
150 void dumpAST(ParsedAST &AST, llvm::raw_ostream &OS);
151 
152 } // namespace clangd
153 } // namespace clang
154 
155 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANGD_PARSEDAST_H
ParsedAST & operator=(ParsedAST &&Other)
const LangOptions & getLangOpts() const
Definition: ParsedAST.h:80
llvm::Optional< ParsedAST > buildAST(PathRef FileName, std::unique_ptr< CompilerInvocation > Invocation, llvm::ArrayRef< Diag > CompilerInvocationDiags, const ParseInputs &Inputs, std::shared_ptr< const PreambleData > Preamble)
Build an AST from provided user inputs.
Definition: ParsedAST.cpp:505
Preprocessor & getPreprocessor()
Definition: ParsedAST.cpp:430
llvm::IntrusiveRefCntPtr< llvm::vfs::FileSystem > VFS
void dumpAST(ParsedAST &AST, llvm::raw_ostream &OS)
For testing/debugging purposes.
Definition: ParsedAST.cpp:213
Interface for symbol indexes that can be used for searching or matching symbols among a set of symbol...
Definition: Index.h:85
llvm::StringRef PathRef
A typedef to represent a ref to file path.
Definition: Path.h:23
ArrayRef< Decl * > getLocalTopLevelDecls()
This function returns top-level decls present in the main file of the AST.
Definition: ParsedAST.cpp:440
const syntax::TokenBuffer & getTokens() const
Tokens recorded while parsing the main file.
Definition: ParsedAST.h:102
ASTContext & getASTContext()
Note that the returned ast will not contain decls from the preamble that were not deserialized during...
Definition: ParsedAST.cpp:424
std::size_t getUsedBytes() const
Returns the estimated size of the AST and the accessory structures, in bytes.
Definition: ParsedAST.cpp:448
Maps a definition location onto an #include file, based on a set of filename rules.
const CanonicalIncludes & getCanonicalIncludes() const
Definition: ParsedAST.cpp:484
const IncludeStructure & getIncludeStructure() const
Definition: ParsedAST.cpp:480
const SourceManager & getSourceManager() const
Definition: ParsedAST.h:76
std::shared_ptr< Preprocessor > getPreprocessorPtr()
Definition: ParsedAST.cpp:432
PathRef FileName
Stores and provides access to parsed AST.
Definition: ParsedAST.h:46
SourceManager & getSourceManager()
Definition: ParsedAST.h:73
const MainFileMacros & getMacros() const
Gets all macro references (definition, expansions) present in the main file, including those in the p...
Definition: ParsedAST.cpp:444
Information required to run clang, e.g. to parse AST or do code completion.
Definition: Compiler.h:44
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
static llvm::Optional< ParsedAST > build(std::unique_ptr< clang::CompilerInvocation > CI, llvm::ArrayRef< Diag > CompilerInvocationDiags, std::shared_ptr< const PreambleData > Preamble, std::unique_ptr< llvm::MemoryBuffer > Buffer, llvm::IntrusiveRefCntPtr< llvm::vfs::FileSystem > VFS, const SymbolIndex *Index, const ParseOptions &Opts)
Attempts to run Clang and store parsed AST.
Definition: ParsedAST.cpp:218
ParsedAST(ParsedAST &&Other)
const std::vector< Diag > & getDiagnostics() const
Definition: ParsedAST.cpp:446
const SymbolIndex * Index
Definition: Dexp.cpp:84