LLVM  8.0.0svn
MCCodeView.h
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1 //===- MCCodeView.h - Machine Code CodeView support -------------*- 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 // Holds state from .cv_file and .cv_loc directives for later emission.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_MC_MCCODEVIEW_H
15 #define LLVM_MC_MCCODEVIEW_H
16 
17 #include "llvm/ADT/StringMap.h"
18 #include "llvm/ADT/StringRef.h"
19 #include "llvm/MC/MCFragment.h"
21 #include <map>
22 #include <vector>
23 
24 namespace llvm {
25 class MCContext;
26 class MCObjectStreamer;
27 class MCStreamer;
28 class CodeViewContext;
29 
30 /// Instances of this class represent the information from a
31 /// .cv_loc directive.
32 class MCCVLoc {
33  const MCSymbol *Label = nullptr;
34  uint32_t FunctionId;
35  uint32_t FileNum;
36  uint32_t Line;
37  uint16_t Column;
38  uint16_t PrologueEnd : 1;
39  uint16_t IsStmt : 1;
40 
41 private: // CodeViewContext manages these
42  friend class CodeViewContext;
43  MCCVLoc(const MCSymbol *Label, unsigned functionid, unsigned fileNum,
44  unsigned line, unsigned column, bool prologueend, bool isstmt)
45  : Label(Label), FunctionId(functionid), FileNum(fileNum), Line(line),
46  Column(column), PrologueEnd(prologueend), IsStmt(isstmt) {}
47 
48  // Allow the default copy constructor and assignment operator to be used
49  // for an MCCVLoc object.
50 
51 public:
52  const MCSymbol *getLabel() const { return Label; }
53 
54  unsigned getFunctionId() const { return FunctionId; }
55 
56  /// Get the FileNum of this MCCVLoc.
57  unsigned getFileNum() const { return FileNum; }
58 
59  /// Get the Line of this MCCVLoc.
60  unsigned getLine() const { return Line; }
61 
62  /// Get the Column of this MCCVLoc.
63  unsigned getColumn() const { return Column; }
64 
65  bool isPrologueEnd() const { return PrologueEnd; }
66  bool isStmt() const { return IsStmt; }
67 
68  void setLabel(const MCSymbol *L) { Label = L; }
69 
70  void setFunctionId(unsigned FID) { FunctionId = FID; }
71 
72  /// Set the FileNum of this MCCVLoc.
73  void setFileNum(unsigned fileNum) { FileNum = fileNum; }
74 
75  /// Set the Line of this MCCVLoc.
76  void setLine(unsigned line) { Line = line; }
77 
78  /// Set the Column of this MCCVLoc.
79  void setColumn(unsigned column) {
80  assert(column <= UINT16_MAX);
81  Column = column;
82  }
83 
84  void setPrologueEnd(bool PE) { PrologueEnd = PE; }
85  void setIsStmt(bool IS) { IsStmt = IS; }
86 };
87 
88 /// Information describing a function or inlined call site introduced by
89 /// .cv_func_id or .cv_inline_site_id. Accumulates information from .cv_loc
90 /// directives used with this function's id or the id of an inlined call site
91 /// within this function or inlined call site.
93  /// If this represents an inlined call site, then ParentFuncIdPlusOne will be
94  /// the parent function id plus one. If this represents a normal function,
95  /// then there is no parent, and ParentFuncIdPlusOne will be FunctionSentinel.
96  /// If this struct is an unallocated slot in the function info vector, then
97  /// ParentFuncIdPlusOne will be zero.
98  unsigned ParentFuncIdPlusOne = 0;
99 
100  enum : unsigned { FunctionSentinel = ~0U };
101 
102  struct LineInfo {
103  unsigned File;
104  unsigned Line;
105  unsigned Col;
106  };
107 
109 
110  /// The section of the first .cv_loc directive used for this function, or null
111  /// if none has been seen yet.
112  MCSection *Section = nullptr;
113 
114  /// Map from inlined call site id to the inlined at location to use for that
115  /// call site. Call chains are collapsed, so for the call chain 'f -> g -> h',
116  /// the InlinedAtMap of 'f' will contain entries for 'g' and 'h' that both
117  /// list the line info for the 'g' call site.
119 
120  /// Returns true if this is function info has not yet been used in a
121  /// .cv_func_id or .cv_inline_site_id directive.
122  bool isUnallocatedFunctionInfo() const { return ParentFuncIdPlusOne == 0; }
123 
124  /// Returns true if this represents an inlined call site, meaning
125  /// ParentFuncIdPlusOne is neither zero nor ~0U.
126  bool isInlinedCallSite() const {
127  return !isUnallocatedFunctionInfo() &&
128  ParentFuncIdPlusOne != FunctionSentinel;
129  }
130 
131  unsigned getParentFuncId() const {
132  assert(isInlinedCallSite());
133  return ParentFuncIdPlusOne - 1;
134  }
135 };
136 
137 /// Holds state from .cv_file and .cv_loc directives for later emission.
139 public:
140  CodeViewContext();
141  ~CodeViewContext();
142 
143  bool isValidFileNumber(unsigned FileNumber) const;
144  bool addFile(MCStreamer &OS, unsigned FileNumber, StringRef Filename,
145  ArrayRef<uint8_t> ChecksumBytes, uint8_t ChecksumKind);
146 
147  /// Records the function id of a normal function. Returns false if the
148  /// function id has already been used, and true otherwise.
149  bool recordFunctionId(unsigned FuncId);
150 
151  /// Records the function id of an inlined call site. Records the "inlined at"
152  /// location info of the call site, including what function or inlined call
153  /// site it was inlined into. Returns false if the function id has already
154  /// been used, and true otherwise.
155  bool recordInlinedCallSiteId(unsigned FuncId, unsigned IAFunc,
156  unsigned IAFile, unsigned IALine,
157  unsigned IACol);
158 
159  /// Retreive the function info if this is a valid function id, or nullptr.
160  MCCVFunctionInfo *getCVFunctionInfo(unsigned FuncId);
161 
162  /// Saves the information from the currently parsed .cv_loc directive
163  /// and sets CVLocSeen. When the next instruction is assembled an entry
164  /// in the line number table with this information and the address of the
165  /// instruction will be created.
166  void recordCVLoc(MCContext &Ctx, const MCSymbol *Label, unsigned FunctionId,
167  unsigned FileNo, unsigned Line, unsigned Column,
168  bool PrologueEnd, bool IsStmt);
169 
170  bool isValidCVFileNumber(unsigned FileNumber);
171 
172  /// Add a line entry.
173  void addLineEntry(const MCCVLoc &LineEntry);
174 
175  std::vector<MCCVLoc> getFunctionLineEntries(unsigned FuncId);
176 
177  std::pair<size_t, size_t> getLineExtent(unsigned FuncId);
178 
179  ArrayRef<MCCVLoc> getLinesForExtent(size_t L, size_t R);
180 
181  /// Emits a line table substream.
182  void emitLineTableForFunction(MCObjectStreamer &OS, unsigned FuncId,
183  const MCSymbol *FuncBegin,
184  const MCSymbol *FuncEnd);
185 
186  void emitInlineLineTableForFunction(MCObjectStreamer &OS,
187  unsigned PrimaryFunctionId,
188  unsigned SourceFileId,
189  unsigned SourceLineNum,
190  const MCSymbol *FnStartSym,
191  const MCSymbol *FnEndSym);
192 
193  /// Encodes the binary annotations once we have a layout.
194  void encodeInlineLineTable(MCAsmLayout &Layout,
196 
197  void
198  emitDefRange(MCObjectStreamer &OS,
199  ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
200  StringRef FixedSizePortion);
201 
202  void encodeDefRange(MCAsmLayout &Layout, MCCVDefRangeFragment &F);
203 
204  /// Emits the string table substream.
205  void emitStringTable(MCObjectStreamer &OS);
206 
207  /// Emits the file checksum substream.
208  void emitFileChecksums(MCObjectStreamer &OS);
209 
210  /// Emits the offset into the checksum table of the given file number.
211  void emitFileChecksumOffset(MCObjectStreamer &OS, unsigned FileNo);
212 
213  /// Add something to the string table. Returns the final string as well as
214  /// offset into the string table.
215  std::pair<StringRef, unsigned> addToStringTable(StringRef S);
216 
217 private:
218  /// Map from string to string table offset.
219  StringMap<unsigned> StringTable;
220 
221  /// The fragment that ultimately holds our strings.
222  MCDataFragment *StrTabFragment = nullptr;
223  bool InsertedStrTabFragment = false;
224 
225  MCDataFragment *getStringTableFragment();
226 
227  /// Get a string table offset.
228  unsigned getStringTableOffset(StringRef S);
229 
230  struct FileInfo {
231  unsigned StringTableOffset;
232 
233  // Indicates if this FileInfo corresponds to an actual file, or hasn't been
234  // set yet.
235  bool Assigned = false;
236 
237  uint8_t ChecksumKind;
238 
239  ArrayRef<uint8_t> Checksum;
240 
241  // Checksum offset stored as a symbol because it might be requested
242  // before it has been calculated, so a fixup may be needed.
243  MCSymbol *ChecksumTableOffset;
244  };
245 
246  /// Array storing added file information.
248 
249  /// The offset of the first and last .cv_loc directive for a given function
250  /// id.
251  std::map<unsigned, std::pair<size_t, size_t>> MCCVLineStartStop;
252 
253  /// A collection of MCCVLoc for each section.
254  std::vector<MCCVLoc> MCCVLines;
255 
256  /// All known functions and inlined call sites, indexed by function id.
257  std::vector<MCCVFunctionInfo> Functions;
258 
259  /// Indicate whether we have already laid out the checksum table addresses or
260  /// not.
261  bool ChecksumOffsetsAssigned = false;
262 };
263 
264 } // end namespace llvm
265 #endif
Profile::FuncID FuncId
Definition: Profile.cpp:321
Instances of this class represent a uniqued identifier for a section in the current translation unit...
Definition: MCSection.h:39
Instances of this class represent the information from a .cv_loc directive.
Definition: MCCodeView.h:32
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
MCSymbol - Instances of this class represent a symbol name in the MC file, and MCSymbols are created ...
Definition: MCSymbol.h:42
bool isPrologueEnd() const
Definition: MCCodeView.h:65
F(f)
DenseMap< unsigned, LineInfo > InlinedAtMap
Map from inlined call site id to the inlined at location to use for that call site.
Definition: MCCodeView.h:118
void setColumn(unsigned column)
Set the Column of this MCCVLoc.
Definition: MCCodeView.h:79
bool isStmt() const
Definition: MCCodeView.h:66
void setIsStmt(bool IS)
Definition: MCCodeView.h:85
Encapsulates the layout of an assembly file at a particular point in time.
Definition: MCAsmLayout.h:29
unsigned getLine() const
Get the Line of this MCCVLoc.
Definition: MCCodeView.h:60
Context object for machine code objects.
Definition: MCContext.h:63
Streaming object file generation interface.
bool isInlinedCallSite() const
Returns true if this represents an inlined call site, meaning ParentFuncIdPlusOne is neither zero nor...
Definition: MCCodeView.h:126
unsigned getParentFuncId() const
Definition: MCCodeView.h:131
friend class CodeViewContext
Definition: MCCodeView.h:42
Streaming machine code generation interface.
Definition: MCStreamer.h:188
void setLabel(const MCSymbol *L)
Definition: MCCodeView.h:68
void setFunctionId(unsigned FID)
Definition: MCCodeView.h:70
void setFileNum(unsigned fileNum)
Set the FileNum of this MCCVLoc.
Definition: MCCodeView.h:73
Fragment representing the .cv_def_range directive.
Definition: MCFragment.h:636
void setLine(unsigned line)
Set the Line of this MCCVLoc.
Definition: MCCodeView.h:76
unsigned getFileNum() const
Get the FileNum of this MCCVLoc.
Definition: MCCodeView.h:57
Fragment representing the binary annotations produced by the .cv_inline_linetable directive...
Definition: MCFragment.h:598
static void addToStringTable(raw_ostream &Out, StringRef ArcName, const NewArchiveMember &M, bool Thin)
bool isUnallocatedFunctionInfo() const
Returns true if this is function info has not yet been used in a .cv_func_id or .cv_inline_site_id di...
Definition: MCCodeView.h:122
void setPrologueEnd(bool PE)
Definition: MCCodeView.h:84
const MCSymbol * getLabel() const
Definition: MCCodeView.h:52
Fragment for data and encoded instructions.
Definition: MCFragment.h:242
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
unsigned getColumn() const
Get the Column of this MCCVLoc.
Definition: MCCodeView.h:63
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
Information describing a function or inlined call site introduced by .cv_func_id or ...
Definition: MCCodeView.h:92
unsigned getFunctionId() const
Definition: MCCodeView.h:54
Holds state from .cv_file and .cv_loc directives for later emission.
Definition: MCCodeView.h:138