1 //===- llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h --------------*- C++ -*-===//
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
7 //===----------------------------------------------------------------------===//
9 // This file contains support for writing Microsoft CodeView debug info.
11 //===----------------------------------------------------------------------===//
13 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H
14 #define LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H
16 #include "llvm/ADT/ArrayRef.h"
17 #include "llvm/ADT/DenseMap.h"
18 #include "llvm/ADT/DenseSet.h"
19 #include "llvm/ADT/MapVector.h"
20 #include "llvm/ADT/PointerUnion.h"
21 #include "llvm/ADT/SetVector.h"
22 #include "llvm/ADT/SmallVector.h"
23 #include "llvm/CodeGen/DbgEntityHistoryCalculator.h"
24 #include "llvm/CodeGen/DebugHandlerBase.h"
25 #include "llvm/DebugInfo/CodeView/CodeView.h"
26 #include "llvm/DebugInfo/CodeView/GlobalTypeTableBuilder.h"
27 #include "llvm/DebugInfo/CodeView/TypeIndex.h"
28 #include "llvm/IR/DebugLoc.h"
29 #include "llvm/Support/Allocator.h"
30 #include "llvm/Support/Compiler.h"
35 #include <unordered_map>
49 class MachineFunction
;
51 /// Collects and handles line tables information in a CodeView format.
52 class LLVM_LIBRARY_VISIBILITY CodeViewDebug
: public DebugHandlerBase
{
54 BumpPtrAllocator Allocator
;
55 codeview::GlobalTypeTableBuilder TypeTable
;
57 /// Whether to emit type record hashes into .debug$H.
58 bool EmitDebugGlobalHashes
= false;
60 /// The codeview CPU type used by the translation unit.
61 codeview::CPUType TheCPU
;
63 /// Represents the most general definition range.
64 struct LocalVarDefRange
{
65 /// Indicates that variable data is stored in memory relative to the
66 /// specified register.
69 /// Offset of variable data in memory.
72 /// Non-zero if this is a piece of an aggregate.
73 uint16_t IsSubfield
: 1;
75 /// Offset into aggregate.
76 uint16_t StructOffset
: 15;
78 /// Register containing the data or the register base of the memory
79 /// location containing the data.
82 /// Compares all location fields. This includes all fields except the label
84 bool isDifferentLocation(LocalVarDefRange
&O
) {
85 return InMemory
!= O
.InMemory
|| DataOffset
!= O
.DataOffset
||
86 IsSubfield
!= O
.IsSubfield
|| StructOffset
!= O
.StructOffset
||
87 CVRegister
!= O
.CVRegister
;
90 SmallVector
<std::pair
<const MCSymbol
*, const MCSymbol
*>, 1> Ranges
;
93 static LocalVarDefRange
createDefRangeMem(uint16_t CVRegister
, int Offset
);
95 /// Similar to DbgVariable in DwarfDebug, but not dwarf-specific.
96 struct LocalVariable
{
97 const DILocalVariable
*DIVar
= nullptr;
98 SmallVector
<LocalVarDefRange
, 1> DefRanges
;
99 bool UseReferenceType
= false;
102 struct CVGlobalVariable
{
103 const DIGlobalVariable
*DIGV
;
104 PointerUnion
<const GlobalVariable
*, const DIExpression
*> GVInfo
;
108 SmallVector
<LocalVariable
, 1> InlinedLocals
;
109 SmallVector
<const DILocation
*, 1> ChildSites
;
110 const DISubprogram
*Inlinee
= nullptr;
112 /// The ID of the inline site or function used with .cv_loc. Not a type
114 unsigned SiteFuncId
= 0;
117 // Combines information from DILexicalBlock and LexicalScope.
118 struct LexicalBlock
{
119 SmallVector
<LocalVariable
, 1> Locals
;
120 SmallVector
<CVGlobalVariable
, 1> Globals
;
121 SmallVector
<LexicalBlock
*, 1> Children
;
122 const MCSymbol
*Begin
;
127 // For each function, store a vector of labels to its instructions, as well as
128 // to the end of the function.
129 struct FunctionInfo
{
130 FunctionInfo() = default;
133 FunctionInfo(const FunctionInfo
&FI
) = delete;
135 /// Map from inlined call site to inlined instructions and child inlined
136 /// call sites. Listed in program order.
137 std::unordered_map
<const DILocation
*, InlineSite
> InlineSites
;
139 /// Ordered list of top-level inlined call sites.
140 SmallVector
<const DILocation
*, 1> ChildSites
;
142 SmallVector
<LocalVariable
, 1> Locals
;
143 SmallVector
<CVGlobalVariable
, 1> Globals
;
145 std::unordered_map
<const DILexicalBlockBase
*, LexicalBlock
> LexicalBlocks
;
147 // Lexical blocks containing local variables.
148 SmallVector
<LexicalBlock
*, 1> ChildBlocks
;
150 std::vector
<std::pair
<MCSymbol
*, MDNode
*>> Annotations
;
151 std::vector
<std::tuple
<MCSymbol
*, MCSymbol
*, const DIType
*>>
154 const MCSymbol
*Begin
= nullptr;
155 const MCSymbol
*End
= nullptr;
157 unsigned LastFileId
= 0;
159 /// Number of bytes allocated in the prologue for all local stack objects.
160 unsigned FrameSize
= 0;
162 /// Number of bytes of parameters on the stack.
163 unsigned ParamSize
= 0;
165 /// Number of bytes pushed to save CSRs.
166 unsigned CSRSize
= 0;
168 /// Adjustment to apply on x86 when using the VFRAME frame pointer.
169 int OffsetAdjustment
= 0;
171 /// Two-bit value indicating which register is the designated frame pointer
172 /// register for local variables. Included in S_FRAMEPROC.
173 codeview::EncodedFramePtrReg EncodedLocalFramePtrReg
=
174 codeview::EncodedFramePtrReg::None
;
176 /// Two-bit value indicating which register is the designated frame pointer
177 /// register for stack parameters. Included in S_FRAMEPROC.
178 codeview::EncodedFramePtrReg EncodedParamFramePtrReg
=
179 codeview::EncodedFramePtrReg::None
;
181 codeview::FrameProcedureOptions FrameProcOpts
;
183 bool HasStackRealignment
= false;
185 bool HaveLineInfo
= false;
187 FunctionInfo
*CurFn
= nullptr;
189 // Map used to seperate variables according to the lexical scope they belong
190 // in. This is populated by recordLocalVariable() before
191 // collectLexicalBlocks() separates the variables between the FunctionInfo
192 // and LexicalBlocks.
193 DenseMap
<const LexicalScope
*, SmallVector
<LocalVariable
, 1>> ScopeVariables
;
195 // Map to separate global variables according to the lexical scope they
196 // belong in. A null local scope represents the global scope.
197 typedef SmallVector
<CVGlobalVariable
, 1> GlobalVariableList
;
198 DenseMap
<const DIScope
*, std::unique_ptr
<GlobalVariableList
> > ScopeGlobals
;
200 // Array of global variables which need to be emitted into a COMDAT section.
201 SmallVector
<CVGlobalVariable
, 1> ComdatVariables
;
203 // Array of non-COMDAT global variables.
204 SmallVector
<CVGlobalVariable
, 1> GlobalVariables
;
206 /// The set of comdat .debug$S sections that we've seen so far. Each section
207 /// must start with a magic version number that must only be emitted once.
208 /// This set tracks which sections we've already opened.
209 DenseSet
<MCSectionCOFF
*> ComdatDebugSections
;
211 /// Switch to the appropriate .debug$S section for GVSym. If GVSym, the symbol
212 /// of an emitted global value, is in a comdat COFF section, this will switch
213 /// to a new .debug$S section in that comdat. This method ensures that the
214 /// section starts with the magic version number on first use. If GVSym is
215 /// null, uses the main .debug$S section.
216 void switchToDebugSectionForSymbol(const MCSymbol
*GVSym
);
218 /// The next available function index for use with our .cv_* directives. Not
219 /// to be confused with type indices for LF_FUNC_ID records.
220 unsigned NextFuncId
= 0;
222 InlineSite
&getInlineSite(const DILocation
*InlinedAt
,
223 const DISubprogram
*Inlinee
);
225 codeview::TypeIndex
getFuncIdForSubprogram(const DISubprogram
*SP
);
227 void calculateRanges(LocalVariable
&Var
,
228 const DbgValueHistoryMap::Entries
&Entries
);
230 static void collectInlineSiteChildren(SmallVectorImpl
<unsigned> &Children
,
231 const FunctionInfo
&FI
,
232 const InlineSite
&Site
);
234 /// Remember some debug info about each function. Keep it in a stable order to
235 /// emit at the end of the TU.
236 MapVector
<const Function
*, std::unique_ptr
<FunctionInfo
>> FnDebugInfo
;
238 /// Map from full file path to .cv_file id. Full paths are built from DIFiles
239 /// and are stored in FileToFilepathMap;
240 DenseMap
<StringRef
, unsigned> FileIdMap
;
242 /// All inlined subprograms in the order they should be emitted.
243 SmallSetVector
<const DISubprogram
*, 4> InlinedSubprograms
;
245 /// Map from a pair of DI metadata nodes and its DI type (or scope) that can
246 /// be nullptr, to CodeView type indices. Primarily indexed by
247 /// {DIType*, DIType*} and {DISubprogram*, DIType*}.
249 /// The second entry in the key is needed for methods as DISubroutineType
250 /// representing static method type are shared with non-method function type.
251 DenseMap
<std::pair
<const DINode
*, const DIType
*>, codeview::TypeIndex
>
254 /// Map from DICompositeType* to complete type index. Non-record types are
255 /// always looked up in the normal TypeIndices map.
256 DenseMap
<const DICompositeType
*, codeview::TypeIndex
> CompleteTypeIndices
;
258 /// Complete record types to emit after all active type lowerings are
260 SmallVector
<const DICompositeType
*, 4> DeferredCompleteTypes
;
262 /// Number of type lowering frames active on the stack.
263 unsigned TypeEmissionLevel
= 0;
265 codeview::TypeIndex VBPType
;
267 const DISubprogram
*CurrentSubprogram
= nullptr;
269 // The UDTs we have seen while processing types; each entry is a pair of type
270 // index and type name.
271 std::vector
<std::pair
<std::string
, const DIType
*>> LocalUDTs
;
272 std::vector
<std::pair
<std::string
, const DIType
*>> GlobalUDTs
;
274 using FileToFilepathMapTy
= std::map
<const DIFile
*, std::string
>;
275 FileToFilepathMapTy FileToFilepathMap
;
277 StringRef
getFullFilepath(const DIFile
*File
);
279 unsigned maybeRecordFile(const DIFile
*F
);
281 void maybeRecordLocation(const DebugLoc
&DL
, const MachineFunction
*MF
);
285 void setCurrentSubprogram(const DISubprogram
*SP
) {
286 CurrentSubprogram
= SP
;
290 /// Emit the magic version number at the start of a CodeView type or symbol
291 /// section. Appears at the front of every .debug$S or .debug$T or .debug$P
293 void emitCodeViewMagicVersion();
295 void emitTypeInformation();
297 void emitTypeGlobalHashes();
299 void emitCompilerInformation();
301 void emitBuildInfo();
303 void emitInlineeLinesSubsection();
305 void emitDebugInfoForThunk(const Function
*GV
,
309 void emitDebugInfoForFunction(const Function
*GV
, FunctionInfo
&FI
);
311 void emitDebugInfoForRetainedTypes();
314 emitDebugInfoForUDTs(ArrayRef
<std::pair
<std::string
, const DIType
*>> UDTs
);
316 void emitDebugInfoForGlobals();
317 void emitGlobalVariableList(ArrayRef
<CVGlobalVariable
> Globals
);
318 void emitDebugInfoForGlobal(const CVGlobalVariable
&CVGV
);
320 /// Opens a subsection of the given kind in a .debug$S codeview section.
321 /// Returns an end label for use with endCVSubsection when the subsection is
323 MCSymbol
*beginCVSubsection(codeview::DebugSubsectionKind Kind
);
324 void endCVSubsection(MCSymbol
*EndLabel
);
326 /// Opens a symbol record of the given kind. Returns an end label for use with
328 MCSymbol
*beginSymbolRecord(codeview::SymbolKind Kind
);
329 void endSymbolRecord(MCSymbol
*SymEnd
);
331 /// Emits an S_END, S_INLINESITE_END, or S_PROC_ID_END record. These records
332 /// are empty, so we emit them with a simpler assembly sequence that doesn't
334 void emitEndSymbolRecord(codeview::SymbolKind EndKind
);
336 void emitInlinedCallSite(const FunctionInfo
&FI
, const DILocation
*InlinedAt
,
337 const InlineSite
&Site
);
339 using InlinedEntity
= DbgValueHistoryMap::InlinedEntity
;
341 void collectGlobalVariableInfo();
342 void collectVariableInfo(const DISubprogram
*SP
);
344 void collectVariableInfoFromMFTable(DenseSet
<InlinedEntity
> &Processed
);
346 // Construct the lexical block tree for a routine, pruning emptpy lexical
347 // scopes, and populate it with local variables.
348 void collectLexicalBlockInfo(SmallVectorImpl
<LexicalScope
*> &Scopes
,
349 SmallVectorImpl
<LexicalBlock
*> &Blocks
,
350 SmallVectorImpl
<LocalVariable
> &Locals
,
351 SmallVectorImpl
<CVGlobalVariable
> &Globals
);
352 void collectLexicalBlockInfo(LexicalScope
&Scope
,
353 SmallVectorImpl
<LexicalBlock
*> &ParentBlocks
,
354 SmallVectorImpl
<LocalVariable
> &ParentLocals
,
355 SmallVectorImpl
<CVGlobalVariable
> &ParentGlobals
);
357 /// Records information about a local variable in the appropriate scope. In
358 /// particular, locals from inlined code live inside the inlining site.
359 void recordLocalVariable(LocalVariable
&&Var
, const LexicalScope
*LS
);
361 /// Emits local variables in the appropriate order.
362 void emitLocalVariableList(const FunctionInfo
&FI
,
363 ArrayRef
<LocalVariable
> Locals
);
365 /// Emits an S_LOCAL record and its associated defined ranges.
366 void emitLocalVariable(const FunctionInfo
&FI
, const LocalVariable
&Var
);
368 /// Emits a sequence of lexical block scopes and their children.
369 void emitLexicalBlockList(ArrayRef
<LexicalBlock
*> Blocks
,
370 const FunctionInfo
& FI
);
372 /// Emit a lexical block scope and its children.
373 void emitLexicalBlock(const LexicalBlock
&Block
, const FunctionInfo
& FI
);
375 /// Translates the DIType to codeview if necessary and returns a type index
377 codeview::TypeIndex
getTypeIndex(const DIType
*Ty
,
378 const DIType
*ClassTy
= nullptr);
381 getTypeIndexForThisPtr(const DIDerivedType
*PtrTy
,
382 const DISubroutineType
*SubroutineTy
);
384 codeview::TypeIndex
getTypeIndexForReferenceTo(const DIType
*Ty
);
386 codeview::TypeIndex
getMemberFunctionType(const DISubprogram
*SP
,
387 const DICompositeType
*Class
);
389 codeview::TypeIndex
getScopeIndex(const DIScope
*Scope
);
391 codeview::TypeIndex
getVBPTypeIndex();
393 void addToUDTs(const DIType
*Ty
);
395 void addUDTSrcLine(const DIType
*Ty
, codeview::TypeIndex TI
);
397 codeview::TypeIndex
lowerType(const DIType
*Ty
, const DIType
*ClassTy
);
398 codeview::TypeIndex
lowerTypeAlias(const DIDerivedType
*Ty
);
399 codeview::TypeIndex
lowerTypeArray(const DICompositeType
*Ty
);
400 codeview::TypeIndex
lowerTypeBasic(const DIBasicType
*Ty
);
401 codeview::TypeIndex
lowerTypePointer(
402 const DIDerivedType
*Ty
,
403 codeview::PointerOptions PO
= codeview::PointerOptions::None
);
404 codeview::TypeIndex
lowerTypeMemberPointer(
405 const DIDerivedType
*Ty
,
406 codeview::PointerOptions PO
= codeview::PointerOptions::None
);
407 codeview::TypeIndex
lowerTypeModifier(const DIDerivedType
*Ty
);
408 codeview::TypeIndex
lowerTypeFunction(const DISubroutineType
*Ty
);
409 codeview::TypeIndex
lowerTypeVFTableShape(const DIDerivedType
*Ty
);
410 codeview::TypeIndex
lowerTypeMemberFunction(
411 const DISubroutineType
*Ty
, const DIType
*ClassTy
, int ThisAdjustment
,
413 codeview::FunctionOptions FO
= codeview::FunctionOptions::None
);
414 codeview::TypeIndex
lowerTypeEnum(const DICompositeType
*Ty
);
415 codeview::TypeIndex
lowerTypeClass(const DICompositeType
*Ty
);
416 codeview::TypeIndex
lowerTypeUnion(const DICompositeType
*Ty
);
418 /// Symbol records should point to complete types, but type records should
419 /// always point to incomplete types to avoid cycles in the type graph. Only
420 /// use this entry point when generating symbol records. The complete and
421 /// incomplete type indices only differ for record types. All other types use
423 codeview::TypeIndex
getCompleteTypeIndex(const DIType
*Ty
);
425 codeview::TypeIndex
lowerCompleteTypeClass(const DICompositeType
*Ty
);
426 codeview::TypeIndex
lowerCompleteTypeUnion(const DICompositeType
*Ty
);
428 struct TypeLoweringScope
;
430 void emitDeferredCompleteTypes();
432 void collectMemberInfo(ClassInfo
&Info
, const DIDerivedType
*DDTy
);
433 ClassInfo
collectClassInfo(const DICompositeType
*Ty
);
435 /// Common record member lowering functionality for record types, which are
436 /// structs, classes, and unions. Returns the field list index and the member
438 std::tuple
<codeview::TypeIndex
, codeview::TypeIndex
, unsigned, bool>
439 lowerRecordFieldList(const DICompositeType
*Ty
);
441 /// Inserts {{Node, ClassTy}, TI} into TypeIndices and checks for duplicates.
442 codeview::TypeIndex
recordTypeIndexForDINode(const DINode
*Node
,
443 codeview::TypeIndex TI
,
444 const DIType
*ClassTy
= nullptr);
446 unsigned getPointerSizeInBytes();
449 /// Gather pre-function debug information.
450 void beginFunctionImpl(const MachineFunction
*MF
) override
;
452 /// Gather post-function debug information.
453 void endFunctionImpl(const MachineFunction
*) override
;
456 CodeViewDebug(AsmPrinter
*AP
);
458 void setSymbolSize(const MCSymbol
*, uint64_t) override
{}
460 /// Emit the COFF section that holds the line table information.
461 void endModule() override
;
463 /// Process beginning of an instruction.
464 void beginInstruction(const MachineInstr
*MI
) override
;
467 } // end namespace llvm
469 #endif // LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H