PTHManager.h revision f056d92e182cbe4f62c8d14102544dc38066dabc 
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_PTHMANAGER_H
15#define LLVM_CLANG_PTHMANAGER_H
16
17#include "clang/Lex/PTHLexer.h"
18#include "clang/Basic/LangOptions.h"
19#include "clang/Basic/IdentifierTable.h"
20#include "llvm/ADT/DenseMap.h"
21#include "llvm/Support/Allocator.h"
22#include <string>
23
24namespace llvm {
25  class MemoryBuffer;
26}
27
28namespace clang {
29
30class FileEntry;
31class PTHLexer;
32class PTHManager;
33
34class PTHSpellingSearch {
35  PTHManager& PTHMgr;
36
37  const char* const TableBeg;
38  const char* const TableEnd;
39
40  const unsigned NumSpellings;
41  const char* LinearItr;
42
43public:
44  enum { SpellingEntrySize = 4*2 };
45
46  unsigned getSpellingBinarySearch(unsigned fpos, const char *&Buffer);
47  unsigned getSpellingLinearSearch(unsigned fpos, const char *&Buffer);
48
49  PTHSpellingSearch(PTHManager& pm, unsigned numSpellings, const char* tableBeg)
50    : PTHMgr(pm),
51      TableBeg(tableBeg),
52      TableEnd(tableBeg + numSpellings*SpellingEntrySize),
53      NumSpellings(numSpellings),
54      LinearItr(tableBeg) {}
55};
56
57class PTHManager : public IdentifierInfoLookup {
58  friend class PTHLexer;
59  friend class PTHSpellingSearch;
60
61  /// The memory mapped PTH file.
62  const llvm::MemoryBuffer* Buf;
63
64  /// A map from FileIDs to SpellingSearch objects.
65  llvm::DenseMap<FileID, PTHSpellingSearch*> SpellingMap;
66
67  /// Alloc - Allocator used for IdentifierInfo objects.
68  llvm::BumpPtrAllocator Alloc;
69
70  /// IdMap - A lazily generated cache mapping from persistent identifiers to
71  ///  IdentifierInfo*.
72  IdentifierInfo** PerIDCache;
73
74  /// FileLookup - Abstract data structure used for mapping between files
75  ///  and token data in the PTH file.
76  void* FileLookup;
77
78  /// IdDataTable - Array representing the mapping from persistent IDs to the
79  ///  data offset within the PTH file containing the information to
80  ///  reconsitute an IdentifierInfo.
81  const char* const IdDataTable;
82
83  /// SortedIdTable - Array ordering persistent identifier IDs by the lexical
84  ///  order of their corresponding strings.  This is used by get().
85  const char* const SortedIdTable;
86
87  /// NumIds - The number of identifiers in the PTH file.
88  const unsigned NumIds;
89
90  /// PP - The Preprocessor object that will use this PTHManager to create
91  ///  PTHLexer objects.
92  Preprocessor* PP;
93
94  /// This constructor is intended to only be called by the static 'Create'
95  /// method.
96  PTHManager(const llvm::MemoryBuffer* buf, void* fileLookup,
97             const char* idDataTable, IdentifierInfo** perIDCache,
98             const char* sortedIdTable, unsigned numIds);
99
100  // Do not implement.
101  PTHManager();
102  void operator=(const PTHManager&);
103
104  /// getSpellingAtPTHOffset - Used by PTHLexer classes to get the cached
105  ///  spelling for a token.
106  unsigned getSpellingAtPTHOffset(unsigned PTHOffset, const char*& Buffer);
107
108
109  /// GetIdentifierInfo - Used to reconstruct IdentifierInfo objects from the
110  ///  PTH file.
111  IdentifierInfo* GetIdentifierInfo(unsigned);
112
113public:
114  ~PTHManager();
115
116  /// get - Return the identifier token info for the specified named identifier.
117  ///  Unlike the version in IdentifierTable, this returns a pointer instead
118  ///  of a reference.  If the pointer is NULL then the IdentifierInfo cannot
119  ///  be found.
120  IdentifierInfo *get(const char *NameStart, const char *NameEnd);
121
122  /// Create - This method creates PTHManager objects.  The 'file' argument
123  ///  is the name of the PTH file.  This method returns NULL upon failure.
124  static PTHManager *Create(const std::string& file);
125
126  void setPreprocessor(Preprocessor *pp) { PP = pp; }
127
128  /// CreateLexer - Return a PTHLexer that "lexes" the cached tokens for the
129  ///  specified file.  This method returns NULL if no cached tokens exist.
130  ///  It is the responsibility of the caller to 'delete' the returned object.
131  PTHLexer *CreateLexer(FileID FID);
132
133  unsigned getSpelling(SourceLocation Loc, const char *&Buffer);
134private:
135  unsigned getSpelling(FileID FID, unsigned fpos, const char *& Buffer);
136};
137
138}  // end namespace clang
139
140#endif
141