1//===- Utils.h - Misc utilities for the front-end ---------------*- 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 header contains miscellaneous utilities for various front-end actions.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_CLANG_FRONTEND_UTILS_H
14#define LLVM_CLANG_FRONTEND_UTILS_H
15
16#include "clang/Basic/Diagnostic.h"
17#include "clang/Basic/LLVM.h"
18#include "clang/Driver/OptionUtils.h"
19#include "clang/Frontend/DependencyOutputOptions.h"
20#include "llvm/ADT/ArrayRef.h"
21#include "llvm/ADT/IntrusiveRefCntPtr.h"
22#include "llvm/ADT/StringMap.h"
23#include "llvm/ADT/StringRef.h"
24#include "llvm/ADT/StringSet.h"
25#include "llvm/Option/OptSpecifier.h"
26#include "llvm/Support/VirtualFileSystem.h"
27#include <cstdint>
28#include <memory>
29#include <string>
30#include <system_error>
31#include <utility>
32#include <vector>
33
34namespace llvm {
35
36class Triple;
37
38} // namespace llvm
39
40namespace clang {
41
42class ASTReader;
43class CompilerInstance;
44class CompilerInvocation;
45class DiagnosticsEngine;
46class ExternalSemaSource;
47class FrontendOptions;
48class HeaderSearch;
49class HeaderSearchOptions;
50class LangOptions;
51class PCHContainerReader;
52class Preprocessor;
53class PreprocessorOptions;
54class PreprocessorOutputOptions;
55
56/// Apply the header search options to get given HeaderSearch object.
57void ApplyHeaderSearchOptions(HeaderSearch &HS,
58                              const HeaderSearchOptions &HSOpts,
59                              const LangOptions &Lang,
60                              const llvm::Triple &triple);
61
62/// InitializePreprocessor - Initialize the preprocessor getting it and the
63/// environment ready to process a single file.
64void InitializePreprocessor(Preprocessor &PP, const PreprocessorOptions &PPOpts,
65                            const PCHContainerReader &PCHContainerRdr,
66                            const FrontendOptions &FEOpts);
67
68/// DoPrintPreprocessedInput - Implement -E mode.
69void DoPrintPreprocessedInput(Preprocessor &PP, raw_ostream *OS,
70                              const PreprocessorOutputOptions &Opts);
71
72/// An interface for collecting the dependencies of a compilation. Users should
73/// use \c attachToPreprocessor and \c attachToASTReader to get all of the
74/// dependencies.
75/// FIXME: Migrate DependencyGraphGen to use this interface.
76class DependencyCollector {
77public:
78  virtual ~DependencyCollector();
79
80  virtual void attachToPreprocessor(Preprocessor &PP);
81  virtual void attachToASTReader(ASTReader &R);
82  ArrayRef<std::string> getDependencies() const { return Dependencies; }
83
84  /// Called when a new file is seen. Return true if \p Filename should be added
85  /// to the list of dependencies.
86  ///
87  /// The default implementation ignores <built-in> and system files.
88  virtual bool sawDependency(StringRef Filename, bool FromModule,
89                             bool IsSystem, bool IsModuleFile, bool IsMissing);
90
91  /// Called when the end of the main file is reached.
92  virtual void finishedMainFile(DiagnosticsEngine &Diags) {}
93
94  /// Return true if system files should be passed to sawDependency().
95  virtual bool needSystemDependencies() { return false; }
96
97  /// Add a dependency \p Filename if it has not been seen before and
98  /// sawDependency() returns true.
99  virtual void maybeAddDependency(StringRef Filename, bool FromModule,
100                                  bool IsSystem, bool IsModuleFile,
101                                  bool IsMissing);
102
103protected:
104  /// Return true if the filename was added to the list of dependencies, false
105  /// otherwise.
106  bool addDependency(StringRef Filename);
107
108private:
109  llvm::StringSet<> Seen;
110  std::vector<std::string> Dependencies;
111};
112
113/// Builds a dependency file when attached to a Preprocessor (for includes) and
114/// ASTReader (for module imports), and writes it out at the end of processing
115/// a source file.  Users should attach to the ast reader whenever a module is
116/// loaded.
117class DependencyFileGenerator : public DependencyCollector {
118public:
119  DependencyFileGenerator(const DependencyOutputOptions &Opts);
120
121  void attachToPreprocessor(Preprocessor &PP) override;
122
123  void finishedMainFile(DiagnosticsEngine &Diags) override;
124
125  bool needSystemDependencies() final override { return IncludeSystemHeaders; }
126
127  bool sawDependency(StringRef Filename, bool FromModule, bool IsSystem,
128                     bool IsModuleFile, bool IsMissing) final override;
129
130protected:
131  void outputDependencyFile(llvm::raw_ostream &OS);
132
133private:
134  void outputDependencyFile(DiagnosticsEngine &Diags);
135
136  std::string OutputFile;
137  std::vector<std::string> Targets;
138  bool IncludeSystemHeaders;
139  bool PhonyTarget;
140  bool AddMissingHeaderDeps;
141  bool SeenMissingHeader;
142  bool IncludeModuleFiles;
143  DependencyOutputFormat OutputFormat;
144  unsigned InputFileIndex;
145};
146
147/// Collects the dependencies for imported modules into a directory.  Users
148/// should attach to the AST reader whenever a module is loaded.
149class ModuleDependencyCollector : public DependencyCollector {
150  std::string DestDir;
151  bool HasErrors = false;
152  llvm::StringSet<> Seen;
153  llvm::vfs::YAMLVFSWriter VFSWriter;
154  llvm::StringMap<std::string> SymLinkMap;
155
156  bool getRealPath(StringRef SrcPath, SmallVectorImpl<char> &Result);
157  std::error_code copyToRoot(StringRef Src, StringRef Dst = {});
158
159public:
160  ModuleDependencyCollector(std::string DestDir)
161      : DestDir(std::move(DestDir)) {}
162  ~ModuleDependencyCollector() override { writeFileMap(); }
163
164  StringRef getDest() { return DestDir; }
165  virtual bool insertSeen(StringRef Filename) { return Seen.insert(Filename).second; }
166  virtual void addFile(StringRef Filename, StringRef FileDst = {});
167
168  virtual void addFileMapping(StringRef VPath, StringRef RPath) {
169    VFSWriter.addFileMapping(VPath, RPath);
170  }
171
172  void attachToPreprocessor(Preprocessor &PP) override;
173  void attachToASTReader(ASTReader &R) override;
174
175  virtual void writeFileMap();
176  virtual bool hasErrors() { return HasErrors; }
177};
178
179/// AttachDependencyGraphGen - Create a dependency graph generator, and attach
180/// it to the given preprocessor.
181void AttachDependencyGraphGen(Preprocessor &PP, StringRef OutputFile,
182                              StringRef SysRoot);
183
184/// AttachHeaderIncludeGen - Create a header include list generator, and attach
185/// it to the given preprocessor.
186///
187/// \param DepOpts - Options controlling the output.
188/// \param ShowAllHeaders - If true, show all header information instead of just
189/// headers following the predefines buffer. This is useful for making sure
190/// includes mentioned on the command line are also reported, but differs from
191/// the default behavior used by -H.
192/// \param OutputPath - If non-empty, a path to write the header include
193/// information to, instead of writing to stderr.
194/// \param ShowDepth - Whether to indent to show the nesting of the includes.
195/// \param MSStyle - Whether to print in cl.exe /showIncludes style.
196void AttachHeaderIncludeGen(Preprocessor &PP,
197                            const DependencyOutputOptions &DepOpts,
198                            bool ShowAllHeaders = false,
199                            StringRef OutputPath = {},
200                            bool ShowDepth = true, bool MSStyle = false);
201
202/// The ChainedIncludesSource class converts headers to chained PCHs in
203/// memory, mainly for testing.
204IntrusiveRefCntPtr<ExternalSemaSource>
205createChainedIncludesSource(CompilerInstance &CI,
206                            IntrusiveRefCntPtr<ExternalSemaSource> &Reader);
207
208/// createInvocationFromCommandLine - Construct a compiler invocation object for
209/// a command line argument vector.
210///
211/// \param ShouldRecoverOnErrors - whether we should attempt to return a
212/// non-null (and possibly incorrect) CompilerInvocation if any errors were
213/// encountered. When this flag is false, always return null on errors.
214///
215/// \param CC1Args - if non-null, will be populated with the args to cc1
216/// expanded from \p Args. May be set even if nullptr is returned.
217///
218/// \return A CompilerInvocation, or nullptr if none was built for the given
219/// argument vector.
220std::unique_ptr<CompilerInvocation> createInvocationFromCommandLine(
221    ArrayRef<const char *> Args,
222    IntrusiveRefCntPtr<DiagnosticsEngine> Diags =
223        IntrusiveRefCntPtr<DiagnosticsEngine>(),
224    IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS = nullptr,
225    bool ShouldRecoverOnErrors = false,
226    std::vector<std::string> *CC1Args = nullptr);
227
228// Frontend timing utils
229
230/// If the user specifies the -ftime-report argument on an Clang command line
231/// then the value of this boolean will be true, otherwise false.
232extern bool FrontendTimesIsEnabled;
233
234} // namespace clang
235
236#endif // LLVM_CLANG_FRONTEND_UTILS_H
237