LLVM  7.0.0svn
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 /// \brief 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  static LocalVarDefRange createDefRangeGeneral(uint16_t CVRegister,
89  bool InMemory, int Offset,
90  bool IsSubfield,
91  uint16_t StructOffset);
92 
93  /// Similar to DbgVariable in DwarfDebug, but not dwarf-specific.
94  struct LocalVariable {
95  const DILocalVariable *DIVar = nullptr;
97  bool UseReferenceType = false;
98  };
99 
100  struct InlineSite {
101  SmallVector<LocalVariable, 1> InlinedLocals;
103  const DISubprogram *Inlinee = nullptr;
104 
105  /// The ID of the inline site or function used with .cv_loc. Not a type
106  /// index.
107  unsigned SiteFuncId = 0;
108  };
109 
110  // For each function, store a vector of labels to its instructions, as well as
111  // to the end of the function.
112  struct FunctionInfo {
113  /// Map from inlined call site to inlined instructions and child inlined
114  /// call sites. Listed in program order.
115  std::unordered_map<const DILocation *, InlineSite> InlineSites;
116 
117  /// Ordered list of top-level inlined call sites.
119 
121 
122  std::vector<std::pair<MCSymbol *, MDNode *>> Annotations;
123 
124  const MCSymbol *Begin = nullptr;
125  const MCSymbol *End = nullptr;
126  unsigned FuncId = 0;
127  unsigned LastFileId = 0;
128  bool HaveLineInfo = false;
129  };
130  FunctionInfo *CurFn = nullptr;
131 
132  /// The set of comdat .debug$S sections that we've seen so far. Each section
133  /// must start with a magic version number that must only be emitted once.
134  /// This set tracks which sections we've already opened.
135  DenseSet<MCSectionCOFF *> ComdatDebugSections;
136 
137  /// Switch to the appropriate .debug$S section for GVSym. If GVSym, the symbol
138  /// of an emitted global value, is in a comdat COFF section, this will switch
139  /// to a new .debug$S section in that comdat. This method ensures that the
140  /// section starts with the magic version number on first use. If GVSym is
141  /// null, uses the main .debug$S section.
142  void switchToDebugSectionForSymbol(const MCSymbol *GVSym);
143 
144  /// The next available function index for use with our .cv_* directives. Not
145  /// to be confused with type indices for LF_FUNC_ID records.
146  unsigned NextFuncId = 0;
147 
148  InlineSite &getInlineSite(const DILocation *InlinedAt,
149  const DISubprogram *Inlinee);
150 
151  codeview::TypeIndex getFuncIdForSubprogram(const DISubprogram *SP);
152 
153  void calculateRanges(LocalVariable &Var,
154  const DbgValueHistoryMap::InstrRanges &Ranges);
155 
156  static void collectInlineSiteChildren(SmallVectorImpl<unsigned> &Children,
157  const FunctionInfo &FI,
158  const InlineSite &Site);
159 
160  /// Remember some debug info about each function. Keep it in a stable order to
161  /// emit at the end of the TU.
163 
164  /// Map from full file path to .cv_file id. Full paths are built from DIFiles
165  /// and are stored in FileToFilepathMap;
167 
168  /// All inlined subprograms in the order they should be emitted.
169  SmallSetVector<const DISubprogram *, 4> InlinedSubprograms;
170 
171  /// Map from a pair of DI metadata nodes and its DI type (or scope) that can
172  /// be nullptr, to CodeView type indices. Primarily indexed by
173  /// {DIType*, DIType*} and {DISubprogram*, DIType*}.
174  ///
175  /// The second entry in the key is needed for methods as DISubroutineType
176  /// representing static method type are shared with non-method function type.
178  TypeIndices;
179 
180  /// Map from DICompositeType* to complete type index. Non-record types are
181  /// always looked up in the normal TypeIndices map.
183 
184  /// Complete record types to emit after all active type lowerings are
185  /// finished.
186  SmallVector<const DICompositeType *, 4> DeferredCompleteTypes;
187 
188  /// Number of type lowering frames active on the stack.
189  unsigned TypeEmissionLevel = 0;
190 
191  codeview::TypeIndex VBPType;
192 
193  const DISubprogram *CurrentSubprogram = nullptr;
194 
195  // The UDTs we have seen while processing types; each entry is a pair of type
196  // index and type name.
197  std::vector<std::pair<std::string, const DIType *>> LocalUDTs;
198  std::vector<std::pair<std::string, const DIType *>> GlobalUDTs;
199 
200  using FileToFilepathMapTy = std::map<const DIFile *, std::string>;
201  FileToFilepathMapTy FileToFilepathMap;
202 
203  StringRef getFullFilepath(const DIFile *S);
204 
205  unsigned maybeRecordFile(const DIFile *F);
206 
207  void maybeRecordLocation(const DebugLoc &DL, const MachineFunction *MF);
208 
209  void clear();
210 
211  void setCurrentSubprogram(const DISubprogram *SP) {
212  CurrentSubprogram = SP;
213  LocalUDTs.clear();
214  }
215 
216  /// Emit the magic version number at the start of a CodeView type or symbol
217  /// section. Appears at the front of every .debug$S or .debug$T section.
218  void emitCodeViewMagicVersion();
219 
220  void emitTypeInformation();
221 
222  void emitTypeGlobalHashes();
223 
224  void emitCompilerInformation();
225 
226  void emitInlineeLinesSubsection();
227 
228  void emitDebugInfoForFunction(const Function *GV, FunctionInfo &FI);
229 
230  void emitDebugInfoForGlobals();
231 
232  void emitDebugInfoForRetainedTypes();
233 
234  void
235  emitDebugInfoForUDTs(ArrayRef<std::pair<std::string, const DIType *>> UDTs);
236 
237  void emitDebugInfoForGlobal(const DIGlobalVariable *DIGV,
238  const GlobalVariable *GV, MCSymbol *GVSym);
239 
240  /// Opens a subsection of the given kind in a .debug$S codeview section.
241  /// Returns an end label for use with endCVSubsection when the subsection is
242  /// finished.
243  MCSymbol *beginCVSubsection(codeview::DebugSubsectionKind Kind);
244 
245  void endCVSubsection(MCSymbol *EndLabel);
246 
247  void emitInlinedCallSite(const FunctionInfo &FI, const DILocation *InlinedAt,
248  const InlineSite &Site);
249 
250  using InlinedVariable = DbgValueHistoryMap::InlinedVariable;
251 
252  void collectVariableInfo(const DISubprogram *SP);
253 
254  void collectVariableInfoFromMFTable(DenseSet<InlinedVariable> &Processed);
255 
256  /// Records information about a local variable in the appropriate scope. In
257  /// particular, locals from inlined code live inside the inlining site.
258  void recordLocalVariable(LocalVariable &&Var, const DILocation *Loc);
259 
260  /// Emits local variables in the appropriate order.
261  void emitLocalVariableList(ArrayRef<LocalVariable> Locals);
262 
263  /// Emits an S_LOCAL record and its associated defined ranges.
264  void emitLocalVariable(const LocalVariable &Var);
265 
266  /// Translates the DIType to codeview if necessary and returns a type index
267  /// for it.
268  codeview::TypeIndex getTypeIndex(DITypeRef TypeRef,
269  DITypeRef ClassTyRef = DITypeRef());
270 
271  codeview::TypeIndex getTypeIndexForReferenceTo(DITypeRef TypeRef);
272 
273  codeview::TypeIndex getMemberFunctionType(const DISubprogram *SP,
274  const DICompositeType *Class);
275 
276  codeview::TypeIndex getScopeIndex(const DIScope *Scope);
277 
278  codeview::TypeIndex getVBPTypeIndex();
279 
280  void addToUDTs(const DIType *Ty);
281 
282  codeview::TypeIndex lowerType(const DIType *Ty, const DIType *ClassTy);
283  codeview::TypeIndex lowerTypeAlias(const DIDerivedType *Ty);
284  codeview::TypeIndex lowerTypeArray(const DICompositeType *Ty);
285  codeview::TypeIndex lowerTypeBasic(const DIBasicType *Ty);
286  codeview::TypeIndex lowerTypePointer(const DIDerivedType *Ty);
287  codeview::TypeIndex lowerTypeMemberPointer(const DIDerivedType *Ty);
288  codeview::TypeIndex lowerTypeModifier(const DIDerivedType *Ty);
289  codeview::TypeIndex lowerTypeFunction(const DISubroutineType *Ty);
290  codeview::TypeIndex lowerTypeVFTableShape(const DIDerivedType *Ty);
291  codeview::TypeIndex lowerTypeMemberFunction(const DISubroutineType *Ty,
292  const DIType *ClassTy,
293  int ThisAdjustment,
294  bool IsStaticMethod);
295  codeview::TypeIndex lowerTypeEnum(const DICompositeType *Ty);
296  codeview::TypeIndex lowerTypeClass(const DICompositeType *Ty);
297  codeview::TypeIndex lowerTypeUnion(const DICompositeType *Ty);
298 
299  /// Symbol records should point to complete types, but type records should
300  /// always point to incomplete types to avoid cycles in the type graph. Only
301  /// use this entry point when generating symbol records. The complete and
302  /// incomplete type indices only differ for record types. All other types use
303  /// the same index.
304  codeview::TypeIndex getCompleteTypeIndex(DITypeRef TypeRef);
305 
306  codeview::TypeIndex lowerCompleteTypeClass(const DICompositeType *Ty);
307  codeview::TypeIndex lowerCompleteTypeUnion(const DICompositeType *Ty);
308 
309  struct TypeLoweringScope;
310 
311  void emitDeferredCompleteTypes();
312 
313  void collectMemberInfo(ClassInfo &Info, const DIDerivedType *DDTy);
314  ClassInfo collectClassInfo(const DICompositeType *Ty);
315 
316  /// Common record member lowering functionality for record types, which are
317  /// structs, classes, and unions. Returns the field list index and the member
318  /// count.
319  std::tuple<codeview::TypeIndex, codeview::TypeIndex, unsigned, bool>
320  lowerRecordFieldList(const DICompositeType *Ty);
321 
322  /// Inserts {{Node, ClassTy}, TI} into TypeIndices and checks for duplicates.
323  codeview::TypeIndex recordTypeIndexForDINode(const DINode *Node,
325  const DIType *ClassTy = nullptr);
326 
327  unsigned getPointerSizeInBytes();
328 
329 protected:
330  /// \brief Gather pre-function debug information.
331  void beginFunctionImpl(const MachineFunction *MF) override;
332 
333  /// \brief Gather post-function debug information.
334  void endFunctionImpl(const MachineFunction *) override;
335 
336 public:
338 
339  void setSymbolSize(const MCSymbol *, uint64_t) override {}
340 
341  /// \brief Emit the COFF section that holds the line table information.
342  void endModule() override;
343 
344  /// \brief Process beginning of an instruction.
345  void beginInstruction(const MachineInstr *MI) override;
346 };
347 
348 } // end namespace llvm
349 
350 #endif // LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
std::pair< const DILocalVariable *, const DILocation * > InlinedVariable
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)
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:143
This class is intended to be used as a driving class for all asm writers.
Definition: AsmPrinter.h:77
static const unsigned End
#define LLVM_LIBRARY_VISIBILITY
LLVM_LIBRARY_VISIBILITY - If a class marked with this attribute is linked into a shared library...
Definition: Compiler.h:105
Base class for scope-like contexts.
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:862
Collects and handles line tables information in a CodeView format.
Definition: CodeViewDebug.h:52
static void clear(coro::Shape &Shape)
Definition: Coroutines.cpp:210
Type array for a subprogram.
Representation of each machine instruction.
Definition: MachineInstr.h:60
Base class for debug information backends.
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;.