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DwarfCompileUnit.h
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1 //===- llvm/CodeGen/DwarfCompileUnit.h - Dwarf Compile Unit -----*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file contains support for writing dwarf compile unit.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_DWARFCOMPILEUNIT_H
14 #define LLVM_LIB_CODEGEN_ASMPRINTER_DWARFCOMPILEUNIT_H
15 
16 #include "DwarfDebug.h"
17 #include "DwarfUnit.h"
18 #include "llvm/ADT/ArrayRef.h"
19 #include "llvm/ADT/DenseMap.h"
20 #include "llvm/ADT/SmallVector.h"
21 #include "llvm/ADT/StringMap.h"
22 #include "llvm/ADT/StringRef.h"
25 #include "llvm/CodeGen/DIE.h"
28 #include "llvm/Support/Casting.h"
29 #include <algorithm>
30 #include <cassert>
31 #include <cstdint>
32 #include <memory>
33 
34 namespace llvm {
35 
36 class AsmPrinter;
37 class DwarfFile;
38 class GlobalVariable;
39 class MCExpr;
40 class MCSymbol;
41 class MDNode;
42 
43 class DwarfCompileUnit final : public DwarfUnit {
44  /// A numeric ID unique among all CUs in the module
45  unsigned UniqueID;
46  bool HasRangeLists = false;
47 
48  /// The attribute index of DW_AT_stmt_list in the compile unit DIE, avoiding
49  /// the need to search for it in applyStmtList.
50  DIE::value_iterator StmtListValue;
51 
52  /// Skeleton unit associated with this unit.
53  DwarfCompileUnit *Skeleton = nullptr;
54 
55  /// The start of the unit within its section.
56  MCSymbol *LabelBegin;
57 
58  /// The start of the unit macro info within macro section.
59  MCSymbol *MacroLabelBegin;
60 
63 
64  ImportedEntityMap ImportedEntities;
65 
66  /// GlobalNames - A map of globally visible named entities for this unit.
67  StringMap<const DIE *> GlobalNames;
68 
69  /// GlobalTypes - A map of globally visible types for this unit.
70  StringMap<const DIE *> GlobalTypes;
71 
72  // List of ranges for a given compile unit.
74 
75  // The base address of this unit, if any. Used for relative references in
76  // ranges/locs.
77  const MCSymbol *BaseAddress = nullptr;
78 
79  DenseMap<const MDNode *, DIE *> AbstractSPDies;
81 
82  /// DWO ID for correlating skeleton and split units.
83  uint64_t DWOId = 0;
84 
85  /// Construct a DIE for the given DbgVariable without initializing the
86  /// DbgVariable's DIE reference.
87  DIE *constructVariableDIEImpl(const DbgVariable &DV, bool Abstract);
88 
89  bool isDwoUnit() const override;
90 
91  DenseMap<const MDNode *, DIE *> &getAbstractSPDies() {
92  if (isDwoUnit() && !DD->shareAcrossDWOCUs())
93  return AbstractSPDies;
94  return DU->getAbstractSPDies();
95  }
96 
98  if (isDwoUnit() && !DD->shareAcrossDWOCUs())
99  return AbstractEntities;
100  return DU->getAbstractEntities();
101  }
102 
103  void finishNonUnitTypeDIE(DIE& D, const DICompositeType *CTy) override;
104 
105 public:
106  DwarfCompileUnit(unsigned UID, const DICompileUnit *Node, AsmPrinter *A,
107  DwarfDebug *DW, DwarfFile *DWU);
108 
109  bool hasRangeLists() const { return HasRangeLists; }
110  unsigned getUniqueID() const { return UniqueID; }
111 
113  return Skeleton;
114  }
115 
116  bool includeMinimalInlineScopes() const;
117 
118  void initStmtList();
119 
120  /// Apply the DW_AT_stmt_list from this compile unit to the specified DIE.
121  void applyStmtList(DIE &D);
122 
123  /// A pair of GlobalVariable and DIExpression.
124  struct GlobalExpr {
127  };
128 
129  struct BaseTypeRef {
130  BaseTypeRef(unsigned BitSize, dwarf::TypeKind Encoding) :
131  BitSize(BitSize), Encoding(Encoding) {}
132  unsigned BitSize;
134  DIE *Die = nullptr;
135  };
136 
137  std::vector<BaseTypeRef> ExprRefedBaseTypes;
138 
139  /// Get or create global variable DIE.
140  DIE *
142  ArrayRef<GlobalExpr> GlobalExprs);
143 
145  ArrayRef<GlobalExpr> GlobalExprs);
146 
147  void addLocationAttribute(DIE *ToDIE, const DIGlobalVariable *GV,
148  ArrayRef<GlobalExpr> GlobalExprs);
149 
150  /// addLabelAddress - Add a dwarf label attribute data and value using
151  /// either DW_FORM_addr or DW_FORM_GNU_addr_index.
153  const MCSymbol *Label);
154 
155  /// addLocalLabelAddress - Add a dwarf label attribute data and value using
156  /// DW_FORM_addr only.
158  const MCSymbol *Label);
159 
160  DwarfCompileUnit &getCU() override { return *this; }
161 
162  unsigned getOrCreateSourceID(const DIFile *File) override;
163 
165  DIScope *Scope = IE->getScope();
166  assert(Scope && "Invalid Scope encoding!");
167  if (!isa<DILocalScope>(Scope))
168  // No need to add imported enities that are not local declaration.
169  return;
170 
171  auto *LocalScope = cast<DILocalScope>(Scope)->getNonLexicalBlockFileScope();
172  ImportedEntities[LocalScope].push_back(IE);
173  }
174 
175  /// addRange - Add an address range to the list of ranges for this unit.
176  void addRange(RangeSpan Range);
177 
178  void attachLowHighPC(DIE &D, const MCSymbol *Begin, const MCSymbol *End);
179 
180  /// Find DIE for the given subprogram and attach appropriate
181  /// DW_AT_low_pc and DW_AT_high_pc attributes. If there are global
182  /// variables in this scope then create and insert DIEs for these
183  /// variables.
185 
186  void constructScopeDIE(LexicalScope *Scope,
187  SmallVectorImpl<DIE *> &FinalChildren);
188 
189  /// A helper function to construct a RangeSpanList for a given
190  /// lexical scope.
191  void addScopeRangeList(DIE &ScopeDIE, SmallVector<RangeSpan, 2> Range);
192 
194 
196  const SmallVectorImpl<InsnRange> &Ranges);
197 
198  /// This scope represents inlined body of a function. Construct
199  /// DIE to represent this concrete inlined copy of the function.
201 
202  /// Construct new DW_TAG_lexical_block for this scope and
203  /// attach DW_AT_low_pc/DW_AT_high_pc labels.
205 
206  /// constructVariableDIE - Construct a DIE for the given DbgVariable.
207  DIE *constructVariableDIE(DbgVariable &DV, bool Abstract = false);
208 
210  DIE *&ObjectPointer);
211 
212  /// Construct a DIE for the given DbgLabel.
213  DIE *constructLabelDIE(DbgLabel &DL, const LexicalScope &Scope);
214 
215  /// A helper function to create children of a Scope DIE.
217  SmallVectorImpl<DIE *> &Children,
218  bool *HasNonScopeChildren = nullptr);
219 
220  void createBaseTypeDIEs();
221 
222  /// Construct a DIE for this subprogram scope.
224  LexicalScope *Scope);
225 
226  DIE *createAndAddScopeChildren(LexicalScope *Scope, DIE &ScopeDIE);
227 
229 
230  /// This takes a DWARF 5 tag and returns it or a GNU analog.
232 
233  /// This takes a DWARF 5 attribute and returns it or a GNU analog.
235 
236  /// This takes a DWARF 5 location atom and either returns it or a GNU analog.
238 
239  /// Construct a call site entry DIE describing a call within \p Scope to a
240  /// callee described by \p CalleeSP.
241  /// \p IsTail specifies whether the call is a tail call.
242  /// \p PCAddr (used for GDB + DWARF 4 tuning) points to the PC value after
243  /// the call instruction.
244  /// \p PCOffset (used for cases other than GDB + DWARF 4 tuning) must be
245  /// non-zero for non-tail calls (in the case of non-gdb tuning, since for
246  /// GDB + DWARF 5 tuning we still generate PC info for tail calls) or be the
247  /// function-local offset to PC value after the call instruction.
248  /// \p CallReg is a register location for an indirect call. For direct calls
249  /// the \p CallReg is set to 0.
250  DIE &constructCallSiteEntryDIE(DIE &ScopeDIE, const DISubprogram *CalleeSP,
251  bool IsTail, const MCSymbol *PCAddr,
252  const MCExpr *PCOffset, unsigned CallReg);
253  /// Construct call site parameter DIEs for the \p CallSiteDIE. The \p Params
254  /// were collected by the \ref collectCallSiteParameters.
255  /// Note: The order of parameters does not matter, since debuggers recognize
256  /// call site parameters by the DW_AT_location attribute.
257  void constructCallSiteParmEntryDIEs(DIE &CallSiteDIE,
259 
260  /// Construct import_module DIE.
262 
264  void finishEntityDefinition(const DbgEntity *Entity);
265 
266  /// Find abstract variable associated with Var.
269  void createAbstractEntity(const DINode *Node, LexicalScope *Scope);
270 
271  /// Set the skeleton unit associated with this unit.
272  void setSkeleton(DwarfCompileUnit &Skel) { Skeleton = &Skel; }
273 
274  unsigned getHeaderSize() const override {
275  // DWARF v5 added the DWO ID to the header for split/skeleton units.
276  unsigned DWOIdSize =
277  DD->getDwarfVersion() >= 5 && DD->useSplitDwarf() ? sizeof(uint64_t)
278  : 0;
279  return DwarfUnit::getHeaderSize() + DWOIdSize;
280  }
281  unsigned getLength() {
282  return sizeof(uint32_t) + // Length field
284  }
285 
286  void emitHeader(bool UseOffsets) override;
287 
288  /// Add the DW_AT_addr_base attribute to the unit DIE.
289  void addAddrTableBase();
290 
292  assert(getSection());
293  return LabelBegin;
294  }
295 
297  return MacroLabelBegin;
298  }
299 
300  /// Add a new global name to the compile unit.
301  void addGlobalName(StringRef Name, const DIE &Die,
302  const DIScope *Context) override;
303 
304  /// Add a new global name present in a type unit to this compile unit.
305  void addGlobalNameForTypeUnit(StringRef Name, const DIScope *Context);
306 
307  /// Add a new global type to the compile unit.
308  void addGlobalType(const DIType *Ty, const DIE &Die,
309  const DIScope *Context) override;
310 
311  /// Add a new global type present in a type unit to this compile unit.
312  void addGlobalTypeUnitType(const DIType *Ty, const DIScope *Context);
313 
314  const StringMap<const DIE *> &getGlobalNames() const { return GlobalNames; }
315  const StringMap<const DIE *> &getGlobalTypes() const { return GlobalTypes; }
316 
317  /// Add DW_AT_location attribute for a DbgVariable based on provided
318  /// MachineLocation.
319  void addVariableAddress(const DbgVariable &DV, DIE &Die,
320  MachineLocation Location);
321  /// Add an address attribute to a die based on the location provided.
323  const MachineLocation &Location);
324 
325  /// Start with the address based on the location provided, and generate the
326  /// DWARF information necessary to find the actual variable (navigating the
327  /// extra location information encoded in the type) based on the starting
328  /// location. Add the DWARF information to the die.
329  void addComplexAddress(const DbgVariable &DV, DIE &Die,
330  dwarf::Attribute Attribute,
331  const MachineLocation &Location);
332 
333  /// Add a Dwarf loclistptr attribute data and value.
334  void addLocationList(DIE &Die, dwarf::Attribute Attribute, unsigned Index);
335  void applyVariableAttributes(const DbgVariable &Var, DIE &VariableDie);
336 
337  /// Add a Dwarf expression attribute data and value.
338  void addExpr(DIELoc &Die, dwarf::Form Form, const MCExpr *Expr);
339 
340  /// Add an attribute containing an address expression to \p Die.
341  void addAddressExpr(DIE &Die, dwarf::Attribute Attribute, const MCExpr *Expr);
342 
344  DIE &SPDie);
345 
346  void applyLabelAttributes(const DbgLabel &Label, DIE &LabelDie);
347 
348  /// getRanges - Get the list of ranges for this unit.
349  const SmallVectorImpl<RangeSpan> &getRanges() const { return CURanges; }
350  SmallVector<RangeSpan, 2> takeRanges() { return std::move(CURanges); }
351 
352  void setBaseAddress(const MCSymbol *Base) { BaseAddress = Base; }
353  const MCSymbol *getBaseAddress() const { return BaseAddress; }
354 
355  uint64_t getDWOId() const { return DWOId; }
356  void setDWOId(uint64_t DwoId) { DWOId = DwoId; }
357 
358  bool hasDwarfPubSections() const;
359 
360  void addBaseTypeRef(DIEValueList &Die, int64_t Idx);
361 };
362 
363 } // end namespace llvm
364 
365 #endif // LLVM_LIB_CODEGEN_ASMPRINTER_DWARFCOMPILEUNIT_H
const StringMap< const DIE * > & getGlobalTypes() const
unsigned getSize() const
Definition: DIE.h:739
LocationAtom
Definition: Dwarf.h:115
std::vector< BaseTypeRef > ExprRefedBaseTypes
LLVMContext & Context
virtual unsigned getHeaderSize() const
Compute the size of a header for this unit, not including the initial length field.
Definition: DwarfUnit.h:258
const MCSymbol * getBaseAddress() const
DIELoc - Represents an expression location.
Definition: DIE.h:891
This class represents lattice values for constants.
Definition: AllocatorList.h:23
MCSymbol - Instances of this class represent a symbol name in the MC file, and MCSymbols are created ...
Definition: MCSymbol.h:41
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:65
amdgpu Simplify well known AMD library false FunctionCallee Value const Twine & Name
void addGlobalName(StringRef Name, const DIE &Die, const DIScope *Context) override
Add a new global name to the compile unit.
void applyLabelAttributes(const DbgLabel &Label, DIE &LabelDie)
Attribute
Attributes.
Definition: Dwarf.h:102
Collects and handles dwarf debug information.
Definition: DwarfDebug.h:292
This class is defined as the common parent of DbgVariable and DbgLabel such that it could levarage po...
Definition: DwarfDebug.h:69
void addRange(RangeSpan Range)
addRange - Add an address range to the list of ranges for this unit.
void attachLowHighPC(DIE &D, const MCSymbol *Begin, const MCSymbol *End)
dwarf::Tag getDwarf5OrGNUTag(dwarf::Tag Tag) const
This takes a DWARF 5 tag and returns it or a GNU analog.
DwarfCompileUnit & getCU() override
LexicalScope - This class is used to track scope information.
Definition: LexicalScopes.h:44
Tagged DWARF-like metadata node.
bool useSplitDwarf() const
Returns whether or not to change the current debug info for the split dwarf proposal support...
Definition: DwarfDebug.h:685
DbgEntity * getExistingAbstractEntity(const DINode *Node)
dwarf::LocationAtom getDwarf5OrGNULocationAtom(dwarf::LocationAtom Loc) const
This takes a DWARF 5 location atom and either returns it or a GNU analog.
void attachRangesOrLowHighPC(DIE &D, SmallVector< RangeSpan, 2 > Ranges)
DIScope * getScope() const
DIE * getOrCreateCommonBlock(const DICommonBlock *CB, ArrayRef< GlobalExpr > GlobalExprs)
void addComplexAddress(const DbgVariable &DV, DIE &Die, dwarf::Attribute Attribute, const MachineLocation &Location)
Start with the address based on the location provided, and generate the DWARF information necessary t...
void constructCallSiteParmEntryDIEs(DIE &CallSiteDIE, SmallVector< DbgCallSiteParam, 4 > &Params)
Construct call site parameter DIEs for the CallSiteDIE.
This class consists of common code factored out of the SmallVector class to reduce code duplication b...
Definition: APFloat.h:41
Base class for the full range of assembler expressions which are needed for parsing.
Definition: MCExpr.h:35
void emitHeader(bool UseOffsets) override
Emit the header for this unit, not including the initial length field.
void addGlobalTypeUnitType(const DIType *Ty, const DIScope *Context)
Add a new global type present in a type unit to this compile unit.
DbgValueHistoryMap::InlinedEntity InlinedEntity
Find abstract variable associated with Var.
DIE & constructCallSiteEntryDIE(DIE &ScopeDIE, const DISubprogram *CalleeSP, bool IsTail, const MCSymbol *PCAddr, const MCExpr *PCOffset, unsigned CallReg)
Construct a call site entry DIE describing a call within Scope to a callee described by CalleeSP...
void setDWOId(uint64_t DwoId)
void createAbstractEntity(const DINode *Node, LexicalScope *Scope)
DIE * constructInlinedScopeDIE(LexicalScope *Scope)
This scope represents inlined body of a function.
Subprogram description.
unsigned getUniqueID() const
uint64_t getDWOId() const
DenseMap< const MDNode *, DIE * > & getAbstractSPDies()
Definition: DwarfFile.h:186
This class is used to track local variable information.
Definition: DwarfDebug.h:118
void setBaseAddress(const MCSymbol *Base)
void addAddrTableBase()
Add the DW_AT_addr_base attribute to the unit DIE.
A list of DIE values.
Definition: DIE.h:627
DIE * constructVariableDIE(DbgVariable &DV, bool Abstract=false)
constructVariableDIE - Construct a DIE for the given DbgVariable.
void addAddressExpr(DIE &Die, dwarf::Attribute Attribute, const MCExpr *Expr)
Add an attribute containing an address expression to Die.
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory)...
Definition: APInt.h:32
void addGlobalNameForTypeUnit(StringRef Name, const DIScope *Context)
Add a new global name present in a type unit to this compile unit.
void addExpr(DIELoc &Die, dwarf::Form Form, const MCExpr *Expr)
Add a Dwarf expression attribute data and value.
This class is used to track label information.
Definition: DwarfDebug.h:230
dwarf::Attribute getDwarf5OrGNUAttr(dwarf::Attribute Attr) const
This takes a DWARF 5 attribute and returns it or a GNU analog.
This dwarf writer support class manages information associated with a source file.
Definition: DwarfUnit.h:40
void addLocationList(DIE &Die, dwarf::Attribute Attribute, unsigned Index)
Add a Dwarf loclistptr attribute data and value.
Instrumentation for Order File
A structured debug information entry.
Definition: DIE.h:700
DIE & getUnitDie()
Definition: DIE.h:879
This class is intended to be used as a driving class for all asm writers.
Definition: AsmPrinter.h:78
unsigned getOrCreateSourceID(const DIFile *File) override
Look up the source ID for the given file.
DIE * createScopeChildrenDIE(LexicalScope *Scope, SmallVectorImpl< DIE *> &Children, bool *HasNonScopeChildren=nullptr)
A helper function to create children of a Scope DIE.
void finishEntityDefinition(const DbgEntity *Entity)
DwarfCompileUnit(unsigned UID, const DICompileUnit *Node, AsmPrinter *A, DwarfDebug *DW, DwarfFile *DWU)
void addAddress(DIE &Die, dwarf::Attribute Attribute, const MachineLocation &Location)
Add an address attribute to a die based on the location provided.
DIE * createAndAddScopeChildren(LexicalScope *Scope, DIE &ScopeDIE)
unsigned getHeaderSize() const override
Compute the size of a header for this unit, not including the initial length field.
DenseMap< const DINode *, std::unique_ptr< DbgEntity > > & getAbstractEntities()
Definition: DwarfFile.h:190
void addLabelAddress(DIE &Die, dwarf::Attribute Attribute, const MCSymbol *Label)
addLabelAddress - Add a dwarf label attribute data and value using either DW_FORM_addr or DW_FORM_GNU...
A pair of GlobalVariable and DIExpression.
void addScopeRangeList(DIE &ScopeDIE, SmallVector< RangeSpan, 2 > Range)
A helper function to construct a RangeSpanList for a given lexical scope.
std::pair< const DINode *, const DILocation * > InlinedEntity
An imported module (C++ using directive or similar).
void setSkeleton(DwarfCompileUnit &Skel)
Set the skeleton unit associated with this unit.
Base class for scope-like contexts.
DIE * constructImportedEntityDIE(const DIImportedEntity *Module)
Construct import_module DIE.
DIE * constructLabelDIE(DbgLabel &DL, const LexicalScope &Scope)
Construct a DIE for the given DbgLabel.
SmallVector< RangeSpan, 2 > takeRanges()
void constructAbstractSubprogramScopeDIE(LexicalScope *Scope)
MCSymbol * getMacroLabelBegin() const
const StringMap< const DIE * > & getGlobalNames() const
Base class for types.
BaseTypeRef(unsigned BitSize, dwarf::TypeKind Encoding)
MCSection * getSection() const
Return the section that this DIEUnit will be emitted into.
Definition: DIE.h:872
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:837
void applySubprogramAttributesToDefinition(const DISubprogram *SP, DIE &SPDie)
void finishSubprogramDefinition(const DISubprogram *SP)
static GCRegistry::Add< StatepointGC > D("statepoint-example", "an example strategy for statepoint")
DWARF expression.
DIE & constructSubprogramScopeDIE(const DISubprogram *Sub, LexicalScope *Scope)
Construct a DIE for this subprogram scope.
StringMap - This is an unconventional map that is specialized for handling keys that are "strings"...
Definition: StringMap.h:219
This file contains constants used for implementing Dwarf debug support.
DwarfDebug * DD
Definition: DwarfUnit.h:55
const SmallVectorImpl< RangeSpan > & getRanges() const
getRanges - Get the list of ranges for this unit.
void addImportedEntity(const DIImportedEntity *IE)
DIE * getOrCreateGlobalVariableDIE(const DIGlobalVariable *GV, ArrayRef< GlobalExpr > GlobalExprs)
Get or create global variable DIE.
void addVariableAddress(const DbgVariable &DV, DIE &Die, MachineLocation Location)
Add DW_AT_location attribute for a DbgVariable based on provided MachineLocation. ...
void addGlobalType(const DIType *Ty, const DIE &Die, const DIScope *Context) override
Add a new global type to the compile unit.
void applyVariableAttributes(const DbgVariable &Var, DIE &VariableDie)
bool shareAcrossDWOCUs() const
Definition: DwarfDebug.cpp:483
void addBaseTypeRef(DIEValueList &Die, int64_t Idx)
bool includeMinimalInlineScopes() const
DwarfCompileUnit * getSkeleton() const
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
void addLocalLabelAddress(DIE &Die, dwarf::Attribute Attribute, const MCSymbol *Label)
addLocalLabelAddress - Add a dwarf label attribute data and value using DW_FORM_addr only...
uint16_t getDwarfVersion() const
Returns the Dwarf Version.
DIE & updateSubprogramScopeDIE(const DISubprogram *SP)
Find DIE for the given subprogram and attach appropriate DW_AT_low_pc and DW_AT_high_pc attributes...
void constructScopeDIE(LexicalScope *Scope, SmallVectorImpl< DIE *> &FinalChildren)
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
DwarfFile * DU
Definition: DwarfUnit.h:56
void addLocationAttribute(DIE *ToDIE, const DIGlobalVariable *GV, ArrayRef< GlobalExpr > GlobalExprs)
MCSymbol * getLabelBegin() const
void applyStmtList(DIE &D)
Apply the DW_AT_stmt_list from this compile unit to the specified DIE.
DIE * constructLexicalScopeDIE(LexicalScope *Scope)
Construct new DW_TAG_lexical_block for this scope and attach DW_AT_low_pc/DW_AT_high_pc labels...