clang  6.0.0svn
PTHManager.h
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1 //===- PTHManager.h - Manager object for PTH processing ---------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file defines the PTHManager interface.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_CLANG_LEX_PTHMANAGER_H
15 #define LLVM_CLANG_LEX_PTHMANAGER_H
16 
19 #include "llvm/ADT/STLExtras.h"
20 #include "llvm/ADT/StringRef.h"
21 #include "llvm/Support/Allocator.h"
22 #include "llvm/Support/OnDiskHashTable.h"
23 #include <memory>
24 
25 namespace llvm {
26 
27 class MemoryBuffer;
28 
29 } // namespace llvm
30 
31 namespace clang {
32 
33 class DiagnosticsEngine;
34 class FileSystemStatCache;
35 class Preprocessor;
36 class PTHLexer;
37 
39  friend class PTHLexer;
40  friend class PTHStatCache;
41 
42  class PTHFileLookupTrait;
44 
47 
48  /// The memory mapped PTH file.
49  std::unique_ptr<const llvm::MemoryBuffer> Buf;
50 
51  /// Alloc - Allocator used for IdentifierInfo objects.
52  llvm::BumpPtrAllocator Alloc;
53 
54  /// IdMap - A lazily generated cache mapping from persistent identifiers to
55  /// IdentifierInfo*.
56  std::unique_ptr<IdentifierInfo *[], llvm::FreeDeleter> PerIDCache;
57 
58  /// FileLookup - Abstract data structure used for mapping between files
59  /// and token data in the PTH file.
60  std::unique_ptr<PTHFileLookup> FileLookup;
61 
62  /// IdDataTable - Array representing the mapping from persistent IDs to the
63  /// data offset within the PTH file containing the information to
64  /// reconsitute an IdentifierInfo.
65  const unsigned char* const IdDataTable;
66 
67  /// SortedIdTable - Abstract data structure mapping from strings to
68  /// persistent IDs. This is used by get().
69  std::unique_ptr<PTHStringIdLookup> StringIdLookup;
70 
71  /// NumIds - The number of identifiers in the PTH file.
72  const unsigned NumIds;
73 
74  /// PP - The Preprocessor object that will use this PTHManager to create
75  /// PTHLexer objects.
76  Preprocessor* PP = nullptr;
77 
78  /// SpellingBase - The base offset within the PTH memory buffer that
79  /// contains the cached spellings for literals.
80  const unsigned char* const SpellingBase;
81 
82  /// OriginalSourceFile - A null-terminated C-string that specifies the name
83  /// if the file (if any) that was to used to generate the PTH cache.
84  const char* OriginalSourceFile;
85 
86  /// This constructor is intended to only be called by the static 'Create'
87  /// method.
88  PTHManager(std::unique_ptr<const llvm::MemoryBuffer> buf,
89  std::unique_ptr<PTHFileLookup> fileLookup,
90  const unsigned char *idDataTable,
91  std::unique_ptr<IdentifierInfo *[], llvm::FreeDeleter> perIDCache,
92  std::unique_ptr<PTHStringIdLookup> stringIdLookup, unsigned numIds,
93  const unsigned char *spellingBase, const char *originalSourceFile);
94 
95  /// getSpellingAtPTHOffset - Used by PTHLexer classes to get the cached
96  /// spelling for a token.
97  unsigned getSpellingAtPTHOffset(unsigned PTHOffset, const char*& Buffer);
98 
99  /// GetIdentifierInfo - Used to reconstruct IdentifierInfo objects from the
100  /// PTH file.
101  IdentifierInfo *GetIdentifierInfo(unsigned PersistentID) {
102  // Check if the IdentifierInfo has already been resolved.
103  if (IdentifierInfo* II = PerIDCache[PersistentID])
104  return II;
105  return LazilyCreateIdentifierInfo(PersistentID);
106  }
107  IdentifierInfo* LazilyCreateIdentifierInfo(unsigned PersistentID);
108 
109 public:
110  // The current PTH version.
111  enum { Version = 10 };
112 
113  PTHManager(const PTHManager &) = delete;
114  PTHManager &operator=(const PTHManager &) = delete;
115  ~PTHManager() override;
116 
117  /// getOriginalSourceFile - Return the full path to the original header
118  /// file name that was used to generate the PTH cache.
119  const char* getOriginalSourceFile() const {
120  return OriginalSourceFile;
121  }
122 
123  /// get - Return the identifier token info for the specified named identifier.
124  /// Unlike the version in IdentifierTable, this returns a pointer instead
125  /// of a reference. If the pointer is nullptr then the IdentifierInfo cannot
126  /// be found.
127  IdentifierInfo *get(StringRef Name) override;
128 
129  /// Create - This method creates PTHManager objects. The 'file' argument
130  /// is the name of the PTH file. This method returns nullptr upon failure.
131  static PTHManager *Create(StringRef file, DiagnosticsEngine &Diags);
132 
133  void setPreprocessor(Preprocessor *pp) { PP = pp; }
134 
135  /// CreateLexer - Return a PTHLexer that "lexes" the cached tokens for the
136  /// specified file. This method returns nullptr if no cached tokens exist.
137  /// It is the responsibility of the caller to 'delete' the returned object.
138  PTHLexer *CreateLexer(FileID FID);
139 
140  /// createStatCache - Returns a FileSystemStatCache object for use with
141  /// FileManager objects. These objects use the PTH data to speed up
142  /// calls to stat by memoizing their results from when the PTH file
143  /// was generated.
144  std::unique_ptr<FileSystemStatCache> createStatCache();
145 };
146 
147 } // namespace clang
148 
149 #endif // LLVM_CLANG_LEX_PTHMANAGER_H
DominatorTree GraphTraits specialization so the DominatorTree can be iterable by generic graph iterat...
Definition: Dominators.h:26
One of these records is kept for each identifier that is lexed.
Concrete class used by the front-end to report problems and issues.
Definition: Diagnostic.h:147
Provides lookups to, and iteration over, IdentiferInfo objects.
Defines the clang::IdentifierInfo, clang::IdentifierTable, and clang::Selector interfaces.
void setPreprocessor(Preprocessor *pp)
Definition: PTHManager.h:133
const char * getOriginalSourceFile() const
getOriginalSourceFile - Return the full path to the original header file name that was used to genera...
Definition: PTHManager.h:119
An opaque identifier used by SourceManager which refers to a source file (MemoryBuffer) along with it...
Dataflow Directional Tag Classes.
Defines the clang::SourceLocation class and associated facilities.
Engages in a tight little dance with the lexer to efficiently preprocess tokens.
Definition: Preprocessor.h:127
static OMPLinearClause * Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc, OpenMPLinearClauseKind Modifier, SourceLocation ModifierLoc, SourceLocation ColonLoc, SourceLocation EndLoc, ArrayRef< Expr *> VL, ArrayRef< Expr *> PL, ArrayRef< Expr *> IL, Expr *Step, Expr *CalcStep, Stmt *PreInit, Expr *PostUpdate)
Creates clause with a list of variables VL and a linear step Step.