LLVM  8.0.0svn
CodeViewDebug.h
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1 //===- llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h --------------*- 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 contains support for writing Microsoft CodeView debug info.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H
15 #define LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H
16 
18 #include "DebugHandlerBase.h"
19 #include "llvm/ADT/ArrayRef.h"
20 #include "llvm/ADT/DenseMap.h"
21 #include "llvm/ADT/DenseSet.h"
22 #include "llvm/ADT/MapVector.h"
23 #include "llvm/ADT/SetVector.h"
24 #include "llvm/ADT/SmallVector.h"
28 #include "llvm/IR/DebugLoc.h"
29 #include "llvm/Support/Allocator.h"
30 #include "llvm/Support/Compiler.h"
31 #include <cstdint>
32 #include <map>
33 #include <string>
34 #include <tuple>
35 #include <unordered_map>
36 #include <utility>
37 #include <vector>
38 
39 namespace llvm {
40 
41 struct ClassInfo;
42 class StringRef;
43 class AsmPrinter;
44 class Function;
45 class GlobalVariable;
46 class MCSectionCOFF;
47 class MCStreamer;
48 class MCSymbol;
49 class MachineFunction;
50 
51 /// Collects and handles line tables information in a CodeView format.
53  MCStreamer &OS;
56 
57  /// Represents the most general definition range.
58  struct LocalVarDefRange {
59  /// Indicates that variable data is stored in memory relative to the
60  /// specified register.
61  int InMemory : 1;
62 
63  /// Offset of variable data in memory.
64  int DataOffset : 31;
65 
66  /// Non-zero if this is a piece of an aggregate.
67  uint16_t IsSubfield : 1;
68 
69  /// Offset into aggregate.
70  uint16_t StructOffset : 15;
71 
72  /// Register containing the data or the register base of the memory
73  /// location containing the data.
74  uint16_t CVRegister;
75 
76  /// Compares all location fields. This includes all fields except the label
77  /// ranges.
78  bool isDifferentLocation(LocalVarDefRange &O) {
79  return InMemory != O.InMemory || DataOffset != O.DataOffset ||
80  IsSubfield != O.IsSubfield || StructOffset != O.StructOffset ||
81  CVRegister != O.CVRegister;
82  }
83 
85  };
86 
87  static LocalVarDefRange createDefRangeMem(uint16_t CVRegister, int Offset);
88 
89  /// Similar to DbgVariable in DwarfDebug, but not dwarf-specific.
90  struct LocalVariable {
91  const DILocalVariable *DIVar = nullptr;
93  bool UseReferenceType = false;
94  };
95 
96  struct InlineSite {
97  SmallVector<LocalVariable, 1> InlinedLocals;
99  const DISubprogram *Inlinee = nullptr;
100 
101  /// The ID of the inline site or function used with .cv_loc. Not a type
102  /// index.
103  unsigned SiteFuncId = 0;
104  };
105 
106  // Combines information from DILexicalBlock and LexicalScope.
107  struct LexicalBlock {
110  const MCSymbol *Begin;
111  const MCSymbol *End;
112  StringRef Name;
113  };
114 
115  // For each function, store a vector of labels to its instructions, as well as
116  // to the end of the function.
117  struct FunctionInfo {
118  FunctionInfo() = default;
119 
120  // Uncopyable.
121  FunctionInfo(const FunctionInfo &FI) = delete;
122 
123  /// Map from inlined call site to inlined instructions and child inlined
124  /// call sites. Listed in program order.
125  std::unordered_map<const DILocation *, InlineSite> InlineSites;
126 
127  /// Ordered list of top-level inlined call sites.
129 
131 
132  std::unordered_map<const DILexicalBlockBase*, LexicalBlock> LexicalBlocks;
133 
134  // Lexical blocks containing local variables.
135  SmallVector<LexicalBlock *, 1> ChildBlocks;
136 
137  std::vector<std::pair<MCSymbol *, MDNode *>> Annotations;
138 
139  const MCSymbol *Begin = nullptr;
140  const MCSymbol *End = nullptr;
141  unsigned FuncId = 0;
142  unsigned LastFileId = 0;
143  bool HaveLineInfo = false;
144  };
145  FunctionInfo *CurFn = nullptr;
146 
147  // Map used to seperate variables according to the lexical scope they belong
148  // in. This is populated by recordLocalVariable() before
149  // collectLexicalBlocks() separates the variables between the FunctionInfo
150  // and LexicalBlocks.
152 
153  /// The set of comdat .debug$S sections that we've seen so far. Each section
154  /// must start with a magic version number that must only be emitted once.
155  /// This set tracks which sections we've already opened.
156  DenseSet<MCSectionCOFF *> ComdatDebugSections;
157 
158  /// Switch to the appropriate .debug$S section for GVSym. If GVSym, the symbol
159  /// of an emitted global value, is in a comdat COFF section, this will switch
160  /// to a new .debug$S section in that comdat. This method ensures that the
161  /// section starts with the magic version number on first use. If GVSym is
162  /// null, uses the main .debug$S section.
163  void switchToDebugSectionForSymbol(const MCSymbol *GVSym);
164 
165  /// The next available function index for use with our .cv_* directives. Not
166  /// to be confused with type indices for LF_FUNC_ID records.
167  unsigned NextFuncId = 0;
168 
169  InlineSite &getInlineSite(const DILocation *InlinedAt,
170  const DISubprogram *Inlinee);
171 
172  codeview::TypeIndex getFuncIdForSubprogram(const DISubprogram *SP);
173 
174  void calculateRanges(LocalVariable &Var,
175  const DbgValueHistoryMap::InstrRanges &Ranges);
176 
177  static void collectInlineSiteChildren(SmallVectorImpl<unsigned> &Children,
178  const FunctionInfo &FI,
179  const InlineSite &Site);
180 
181  /// Remember some debug info about each function. Keep it in a stable order to
182  /// emit at the end of the TU.
184 
185  /// Map from full file path to .cv_file id. Full paths are built from DIFiles
186  /// and are stored in FileToFilepathMap;
188 
189  /// All inlined subprograms in the order they should be emitted.
190  SmallSetVector<const DISubprogram *, 4> InlinedSubprograms;
191 
192  /// Map from a pair of DI metadata nodes and its DI type (or scope) that can
193  /// be nullptr, to CodeView type indices. Primarily indexed by
194  /// {DIType*, DIType*} and {DISubprogram*, DIType*}.
195  ///
196  /// The second entry in the key is needed for methods as DISubroutineType
197  /// representing static method type are shared with non-method function type.
199  TypeIndices;
200 
201  /// Map from DICompositeType* to complete type index. Non-record types are
202  /// always looked up in the normal TypeIndices map.
204 
205  /// Complete record types to emit after all active type lowerings are
206  /// finished.
207  SmallVector<const DICompositeType *, 4> DeferredCompleteTypes;
208 
209  /// Number of type lowering frames active on the stack.
210  unsigned TypeEmissionLevel = 0;
211 
212  codeview::TypeIndex VBPType;
213 
214  const DISubprogram *CurrentSubprogram = nullptr;
215 
216  // The UDTs we have seen while processing types; each entry is a pair of type
217  // index and type name.
218  std::vector<std::pair<std::string, const DIType *>> LocalUDTs;
219  std::vector<std::pair<std::string, const DIType *>> GlobalUDTs;
220 
221  using FileToFilepathMapTy = std::map<const DIFile *, std::string>;
222  FileToFilepathMapTy FileToFilepathMap;
223 
224  StringRef getFullFilepath(const DIFile *File);
225 
226  unsigned maybeRecordFile(const DIFile *F);
227 
228  void maybeRecordLocation(const DebugLoc &DL, const MachineFunction *MF);
229 
230  void clear();
231 
232  void setCurrentSubprogram(const DISubprogram *SP) {
233  CurrentSubprogram = SP;
234  LocalUDTs.clear();
235  }
236 
237  /// Emit the magic version number at the start of a CodeView type or symbol
238  /// section. Appears at the front of every .debug$S or .debug$T or .debug$P
239  /// section.
240  void emitCodeViewMagicVersion();
241 
242  void emitTypeInformation();
243 
244  void emitTypeGlobalHashes();
245 
246  void emitCompilerInformation();
247 
248  void emitInlineeLinesSubsection();
249 
250  void emitDebugInfoForThunk(const Function *GV,
251  FunctionInfo &FI,
252  const MCSymbol *Fn);
253 
254  void emitDebugInfoForFunction(const Function *GV, FunctionInfo &FI);
255 
256  void emitDebugInfoForGlobals();
257 
258  void emitDebugInfoForRetainedTypes();
259 
260  void
261  emitDebugInfoForUDTs(ArrayRef<std::pair<std::string, const DIType *>> UDTs);
262 
263  void emitDebugInfoForGlobal(const DIGlobalVariable *DIGV,
264  const GlobalVariable *GV, MCSymbol *GVSym);
265 
266  /// Opens a subsection of the given kind in a .debug$S codeview section.
267  /// Returns an end label for use with endCVSubsection when the subsection is
268  /// finished.
269  MCSymbol *beginCVSubsection(codeview::DebugSubsectionKind Kind);
270 
271  void endCVSubsection(MCSymbol *EndLabel);
272 
273  void emitInlinedCallSite(const FunctionInfo &FI, const DILocation *InlinedAt,
274  const InlineSite &Site);
275 
276  using InlinedEntity = DbgValueHistoryMap::InlinedEntity;
277 
278  void collectVariableInfo(const DISubprogram *SP);
279 
280  void collectVariableInfoFromMFTable(DenseSet<InlinedEntity> &Processed);
281 
282  // Construct the lexical block tree for a routine, pruning emptpy lexical
283  // scopes, and populate it with local variables.
284  void collectLexicalBlockInfo(SmallVectorImpl<LexicalScope *> &Scopes,
287  void collectLexicalBlockInfo(LexicalScope &Scope,
288  SmallVectorImpl<LexicalBlock *> &ParentBlocks,
289  SmallVectorImpl<LocalVariable> &ParentLocals);
290 
291  /// Records information about a local variable in the appropriate scope. In
292  /// particular, locals from inlined code live inside the inlining site.
293  void recordLocalVariable(LocalVariable &&Var, const LexicalScope *LS);
294 
295  /// Emits local variables in the appropriate order.
296  void emitLocalVariableList(ArrayRef<LocalVariable> Locals);
297 
298  /// Emits an S_LOCAL record and its associated defined ranges.
299  void emitLocalVariable(const LocalVariable &Var);
300 
301  /// Emits a sequence of lexical block scopes and their children.
302  void emitLexicalBlockList(ArrayRef<LexicalBlock *> Blocks,
303  const FunctionInfo& FI);
304 
305  /// Emit a lexical block scope and its children.
306  void emitLexicalBlock(const LexicalBlock &Block, const FunctionInfo& FI);
307 
308  /// Translates the DIType to codeview if necessary and returns a type index
309  /// for it.
310  codeview::TypeIndex getTypeIndex(DITypeRef TypeRef,
311  DITypeRef ClassTyRef = DITypeRef());
312 
313  codeview::TypeIndex getTypeIndexForReferenceTo(DITypeRef TypeRef);
314 
315  codeview::TypeIndex getMemberFunctionType(const DISubprogram *SP,
316  const DICompositeType *Class);
317 
318  codeview::TypeIndex getScopeIndex(const DIScope *Scope);
319 
320  codeview::TypeIndex getVBPTypeIndex();
321 
322  void addToUDTs(const DIType *Ty);
323 
324  void addUDTSrcLine(const DIType *Ty, codeview::TypeIndex TI);
325 
326  codeview::TypeIndex lowerType(const DIType *Ty, const DIType *ClassTy);
327  codeview::TypeIndex lowerTypeAlias(const DIDerivedType *Ty);
328  codeview::TypeIndex lowerTypeArray(const DICompositeType *Ty);
329  codeview::TypeIndex lowerTypeBasic(const DIBasicType *Ty);
330  codeview::TypeIndex lowerTypePointer(
331  const DIDerivedType *Ty,
333  codeview::TypeIndex lowerTypeMemberPointer(
334  const DIDerivedType *Ty,
336  codeview::TypeIndex lowerTypeModifier(const DIDerivedType *Ty);
337  codeview::TypeIndex lowerTypeFunction(const DISubroutineType *Ty);
338  codeview::TypeIndex lowerTypeVFTableShape(const DIDerivedType *Ty);
339  codeview::TypeIndex lowerTypeMemberFunction(const DISubroutineType *Ty,
340  const DIType *ClassTy,
341  int ThisAdjustment,
342  bool IsStaticMethod);
343  codeview::TypeIndex lowerTypeEnum(const DICompositeType *Ty);
344  codeview::TypeIndex lowerTypeClass(const DICompositeType *Ty);
345  codeview::TypeIndex lowerTypeUnion(const DICompositeType *Ty);
346 
347  /// Symbol records should point to complete types, but type records should
348  /// always point to incomplete types to avoid cycles in the type graph. Only
349  /// use this entry point when generating symbol records. The complete and
350  /// incomplete type indices only differ for record types. All other types use
351  /// the same index.
352  codeview::TypeIndex getCompleteTypeIndex(DITypeRef TypeRef);
353 
354  codeview::TypeIndex lowerCompleteTypeClass(const DICompositeType *Ty);
355  codeview::TypeIndex lowerCompleteTypeUnion(const DICompositeType *Ty);
356 
357  struct TypeLoweringScope;
358 
359  void emitDeferredCompleteTypes();
360 
361  void collectMemberInfo(ClassInfo &Info, const DIDerivedType *DDTy);
362  ClassInfo collectClassInfo(const DICompositeType *Ty);
363 
364  /// Common record member lowering functionality for record types, which are
365  /// structs, classes, and unions. Returns the field list index and the member
366  /// count.
367  std::tuple<codeview::TypeIndex, codeview::TypeIndex, unsigned, bool>
368  lowerRecordFieldList(const DICompositeType *Ty);
369 
370  /// Inserts {{Node, ClassTy}, TI} into TypeIndices and checks for duplicates.
371  codeview::TypeIndex recordTypeIndexForDINode(const DINode *Node,
373  const DIType *ClassTy = nullptr);
374 
375  unsigned getPointerSizeInBytes();
376 
377 protected:
378  /// Gather pre-function debug information.
379  void beginFunctionImpl(const MachineFunction *MF) override;
380 
381  /// Gather post-function debug information.
382  void endFunctionImpl(const MachineFunction *) override;
383 
384 public:
386 
387  void setSymbolSize(const MCSymbol *, uint64_t) override {}
388 
389  /// Emit the COFF section that holds the line table information.
390  void endModule() override;
391 
392  /// Process beginning of an instruction.
393  void beginInstruction(const MachineInstr *MI) override;
394 };
395 
396 } // end namespace llvm
397 
398 #endif // LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H
Profile::FuncID FuncId
Definition: Profile.cpp:321
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
Implements a dense probed hash-table based set.
Definition: DenseSet.h:221
This class implements a map that also provides access to all stored values in a deterministic order...
Definition: MapVector.h:38
A debug info location.
Definition: DebugLoc.h:34
F(f)
LexicalScope - This class is used to track scope information.
Definition: LexicalScopes.h:45
This file defines the MallocAllocator and BumpPtrAllocator interfaces.
Tagged DWARF-like metadata node.
void setSymbolSize(const MCSymbol *, uint64_t) override
For symbols that have a size designated (e.g.
Holds a subclass of DINode.
Subprogram description.
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory)...
Definition: APInt.h:33
A 32-bit type reference.
Definition: TypeIndex.h:96
Debug location.
Streaming machine code generation interface.
Definition: MCStreamer.h:183
Allocate memory in an ever growing pool, as if by bump-pointer.
Definition: Allocator.h:141
This class is intended to be used as a driving class for all asm writers.
Definition: AsmPrinter.h:78
std::pair< const DINode *, const DILocation * > InlinedEntity
Base class for scope-like contexts.
PointerOptions
Equivalent to misc lfPointerAttr bitfields.
Definition: CodeView.h:354
Basic Register Allocator
A SetVector that performs no allocations if smaller than a certain size.
Definition: SetVector.h:298
Base class for types.
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:847
Collects and handles line tables information in a CodeView format.
Definition: CodeViewDebug.h:52
static void clear(coro::Shape &Shape)
Definition: Coroutines.cpp:212
Type array for a subprogram.
Representation of each machine instruction.
Definition: MachineInstr.h:64
Base class for debug information backends.
#define LLVM_LIBRARY_VISIBILITY
LLVM_LIBRARY_VISIBILITY - If a class marked with this attribute is linked into a shared library...
Definition: Compiler.h:108
const unsigned Kind
IRTranslator LLVM IR MI
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
TypedDINodeRef< DIType > DITypeRef
Basic type, like &#39;int&#39; or &#39;float&#39;.