1 #include "DwarfCompileUnit.h"
2 #include "DwarfExpression.h"
3 #include "llvm/CodeGen/MachineFunction.h"
4 #include "llvm/IR/Constants.h"
5 #include "llvm/IR/DataLayout.h"
6 #include "llvm/IR/GlobalValue.h"
7 #include "llvm/IR/GlobalVariable.h"
8 #include "llvm/IR/Instruction.h"
9 #include "llvm/MC/MCAsmInfo.h"
10 #include "llvm/MC/MCStreamer.h"
11 #include "llvm/Target/TargetFrameLowering.h"
12 #include "llvm/Target/TargetLoweringObjectFile.h"
13 #include "llvm/Target/TargetMachine.h"
14 #include "llvm/Target/TargetRegisterInfo.h"
15 #include "llvm/Target/TargetSubtargetInfo.h"
19 DwarfCompileUnit::DwarfCompileUnit(unsigned UID, const DICompileUnit *Node,
20 AsmPrinter *A, DwarfDebug *DW,
22 : DwarfUnit(dwarf::DW_TAG_compile_unit, Node, A, DW, DWU), UniqueID(UID),
23 Skeleton(nullptr), BaseAddress(nullptr) {
24 insertDIE(Node, &getUnitDie());
25 MacroLabelBegin = Asm->createTempSymbol("cu_macro_begin");
28 /// addLabelAddress - Add a dwarf label attribute data and value using
29 /// DW_FORM_addr or DW_FORM_GNU_addr_index.
31 void DwarfCompileUnit::addLabelAddress(DIE &Die, dwarf::Attribute Attribute,
32 const MCSymbol *Label) {
34 // Don't use the address pool in non-fission or in the skeleton unit itself.
35 // FIXME: Once GDB supports this, it's probably worthwhile using the address
36 // pool from the skeleton - maybe even in non-fission (possibly fewer
37 // relocations by sharing them in the pool, but we have other ideas about how
38 // to reduce the number of relocations as well/instead).
39 if (!DD->useSplitDwarf() || !Skeleton)
40 return addLocalLabelAddress(Die, Attribute, Label);
43 DD->addArangeLabel(SymbolCU(this, Label));
45 unsigned idx = DD->getAddressPool().getIndex(Label);
46 Die.addValue(DIEValueAllocator, Attribute, dwarf::DW_FORM_GNU_addr_index,
50 void DwarfCompileUnit::addLocalLabelAddress(DIE &Die,
51 dwarf::Attribute Attribute,
52 const MCSymbol *Label) {
54 DD->addArangeLabel(SymbolCU(this, Label));
57 Die.addValue(DIEValueAllocator, Attribute, dwarf::DW_FORM_addr,
60 Die.addValue(DIEValueAllocator, Attribute, dwarf::DW_FORM_addr,
64 unsigned DwarfCompileUnit::getOrCreateSourceID(StringRef FileName,
66 // If we print assembly, we can't separate .file entries according to
67 // compile units. Thus all files will belong to the default compile unit.
69 // FIXME: add a better feature test than hasRawTextSupport. Even better,
70 // extend .file to support this.
71 return Asm->OutStreamer->EmitDwarfFileDirective(
73 Asm->OutStreamer->hasRawTextSupport() ? 0 : getUniqueID());
76 DIE *DwarfCompileUnit::getOrCreateGlobalVariableDIE(
77 const DIGlobalVariable *GV, ArrayRef<GlobalExpr> GlobalExprs) {
78 // Check for pre-existence.
79 if (DIE *Die = getDIE(GV))
84 auto *GVContext = GV->getScope();
85 auto *GTy = DD->resolve(GV->getType());
87 // Construct the context before querying for the existence of the DIE in
88 // case such construction creates the DIE.
89 DIE *ContextDIE = getOrCreateContextDIE(GVContext);
92 DIE *VariableDIE = &createAndAddDIE(GV->getTag(), *ContextDIE, GV);
94 if (auto *SDMDecl = GV->getStaticDataMemberDeclaration()) {
95 DeclContext = resolve(SDMDecl->getScope());
96 assert(SDMDecl->isStaticMember() && "Expected static member decl");
97 assert(GV->isDefinition());
98 // We need the declaration DIE that is in the static member's class.
99 DIE *VariableSpecDIE = getOrCreateStaticMemberDIE(SDMDecl);
100 addDIEEntry(*VariableDIE, dwarf::DW_AT_specification, *VariableSpecDIE);
101 // If the global variable's type is different from the one in the class
102 // member type, assume that it's more specific and also emit it.
103 if (GTy != DD->resolve(SDMDecl->getBaseType()))
104 addType(*VariableDIE, GTy);
106 DeclContext = GV->getScope();
107 // Add name and type.
108 addString(*VariableDIE, dwarf::DW_AT_name, GV->getDisplayName());
109 addType(*VariableDIE, GTy);
112 if (!GV->isLocalToUnit())
113 addFlag(*VariableDIE, dwarf::DW_AT_external);
115 // Add line number info.
116 addSourceLine(*VariableDIE, GV);
119 if (!GV->isDefinition())
120 addFlag(*VariableDIE, dwarf::DW_AT_declaration);
122 addGlobalName(GV->getName(), *VariableDIE, DeclContext);
124 if (uint32_t AlignInBytes = GV->getAlignInBytes())
125 addUInt(*VariableDIE, dwarf::DW_AT_alignment, dwarf::DW_FORM_udata,
129 bool addToAccelTable = false;
130 DIELoc *Loc = nullptr;
131 std::unique_ptr<DIEDwarfExpression> DwarfExpr;
132 bool AllConstant = std::all_of(
133 GlobalExprs.begin(), GlobalExprs.end(),
134 [&](const GlobalExpr GE) {
135 return GE.Expr && GE.Expr->isConstant();
138 for (const auto &GE : GlobalExprs) {
139 const GlobalVariable *Global = GE.Var;
140 const DIExpression *Expr = GE.Expr;
141 // For compatibility with DWARF 3 and earlier,
142 // DW_AT_location(DW_OP_constu, X, DW_OP_stack_value) becomes
143 // DW_AT_const_value(X).
144 if (GlobalExprs.size() == 1 && Expr && Expr->isConstant()) {
145 addConstantValue(*VariableDIE, /*Unsigned=*/true, Expr->getElement(1));
146 // We cannot describe the location of dllimport'd variables: the
147 // computation of their address requires loads from the IAT.
148 } else if ((Global && !Global->hasDLLImportStorageClass()) || AllConstant) {
150 Loc = new (DIEValueAllocator) DIELoc;
151 DwarfExpr = llvm::make_unique<DIEDwarfExpression>(*Asm, *this, *Loc);
153 addToAccelTable = true;
155 const MCSymbol *Sym = Asm->getSymbol(Global);
156 if (Global->isThreadLocal()) {
157 if (Asm->TM.Options.EmulatedTLS) {
158 // TODO: add debug info for emulated thread local mode.
160 // FIXME: Make this work with -gsplit-dwarf.
161 unsigned PointerSize = Asm->getDataLayout().getPointerSize();
162 assert((PointerSize == 4 || PointerSize == 8) &&
163 "Add support for other sizes if necessary");
164 // Based on GCC's support for TLS:
165 if (!DD->useSplitDwarf()) {
166 // 1) Start with a constNu of the appropriate pointer size
167 addUInt(*Loc, dwarf::DW_FORM_data1,
168 PointerSize == 4 ? dwarf::DW_OP_const4u
169 : dwarf::DW_OP_const8u);
170 // 2) containing the (relocated) offset of the TLS variable
171 // within the module's TLS block.
172 addExpr(*Loc, dwarf::DW_FORM_udata,
173 Asm->getObjFileLowering().getDebugThreadLocalSymbol(Sym));
175 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_GNU_const_index);
176 addUInt(*Loc, dwarf::DW_FORM_udata,
177 DD->getAddressPool().getIndex(Sym, /* TLS */ true));
179 // 3) followed by an OP to make the debugger do a TLS lookup.
180 addUInt(*Loc, dwarf::DW_FORM_data1,
181 DD->useGNUTLSOpcode() ? dwarf::DW_OP_GNU_push_tls_address
182 : dwarf::DW_OP_form_tls_address);
185 DD->addArangeLabel(SymbolCU(this, Sym));
186 addOpAddress(*Loc, Sym);
190 DwarfExpr->addFragmentOffset(Expr);
191 DwarfExpr->AddExpression(Expr);
196 addBlock(*VariableDIE, dwarf::DW_AT_location, DwarfExpr->finalize());
198 if (DD->useAllLinkageNames())
199 addLinkageName(*VariableDIE, GV->getLinkageName());
201 if (addToAccelTable) {
202 DD->addAccelName(GV->getName(), *VariableDIE);
204 // If the linkage name is different than the name, go ahead and output
205 // that as well into the name table.
206 if (GV->getLinkageName() != "" && GV->getName() != GV->getLinkageName())
207 DD->addAccelName(GV->getLinkageName(), *VariableDIE);
213 void DwarfCompileUnit::addRange(RangeSpan Range) {
214 bool SameAsPrevCU = this == DD->getPrevCU();
216 // If we have no current ranges just add the range and return, otherwise,
217 // check the current section and CU against the previous section and CU we
218 // emitted into and the subprogram was contained within. If these are the
219 // same then extend our current range, otherwise add this as a new range.
220 if (CURanges.empty() || !SameAsPrevCU ||
221 (&CURanges.back().getEnd()->getSection() !=
222 &Range.getEnd()->getSection())) {
223 CURanges.push_back(Range);
227 CURanges.back().setEnd(Range.getEnd());
231 DwarfCompileUnit::addSectionLabel(DIE &Die, dwarf::Attribute Attribute,
232 const MCSymbol *Label, const MCSymbol *Sec) {
233 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
234 return addLabel(Die, Attribute,
235 DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
236 : dwarf::DW_FORM_data4,
238 return addSectionDelta(Die, Attribute, Label, Sec);
241 void DwarfCompileUnit::initStmtList() {
242 // Define start line table label for each Compile Unit.
243 MCSymbol *LineTableStartSym =
244 Asm->OutStreamer->getDwarfLineTableSymbol(getUniqueID());
246 // DW_AT_stmt_list is a offset of line number information for this
247 // compile unit in debug_line section. For split dwarf this is
248 // left in the skeleton CU and so not included.
249 // The line table entries are not always emitted in assembly, so it
250 // is not okay to use line_table_start here.
251 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
253 addSectionLabel(getUnitDie(), dwarf::DW_AT_stmt_list, LineTableStartSym,
254 TLOF.getDwarfLineSection()->getBeginSymbol());
257 void DwarfCompileUnit::applyStmtList(DIE &D) {
258 D.addValue(DIEValueAllocator, *StmtListValue);
261 void DwarfCompileUnit::attachLowHighPC(DIE &D, const MCSymbol *Begin,
262 const MCSymbol *End) {
263 assert(Begin && "Begin label should not be null!");
264 assert(End && "End label should not be null!");
265 assert(Begin->isDefined() && "Invalid starting label");
266 assert(End->isDefined() && "Invalid end label");
268 addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
269 if (DD->getDwarfVersion() < 4)
270 addLabelAddress(D, dwarf::DW_AT_high_pc, End);
272 addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
275 // Find DIE for the given subprogram and attach appropriate DW_AT_low_pc
276 // and DW_AT_high_pc attributes. If there are global variables in this
277 // scope then create and insert DIEs for these variables.
278 DIE &DwarfCompileUnit::updateSubprogramScopeDIE(const DISubprogram *SP) {
279 DIE *SPDie = getOrCreateSubprogramDIE(SP, includeMinimalInlineScopes());
281 attachLowHighPC(*SPDie, Asm->getFunctionBegin(), Asm->getFunctionEnd());
282 if (DD->useAppleExtensionAttributes() &&
283 !DD->getCurrentFunction()->getTarget().Options.DisableFramePointerElim(
284 *DD->getCurrentFunction()))
285 addFlag(*SPDie, dwarf::DW_AT_APPLE_omit_frame_ptr);
287 // Only include DW_AT_frame_base in full debug info
288 if (!includeMinimalInlineScopes()) {
289 const TargetRegisterInfo *RI = Asm->MF->getSubtarget().getRegisterInfo();
290 MachineLocation Location(RI->getFrameRegister(*Asm->MF));
291 if (RI->isPhysicalRegister(Location.getReg()))
292 addAddress(*SPDie, dwarf::DW_AT_frame_base, Location);
295 // Add name to the name table, we do this here because we're guaranteed
296 // to have concrete versions of our DW_TAG_subprogram nodes.
297 DD->addSubprogramNames(SP, *SPDie);
302 // Construct a DIE for this scope.
303 void DwarfCompileUnit::constructScopeDIE(
304 LexicalScope *Scope, SmallVectorImpl<DIE *> &FinalChildren) {
305 if (!Scope || !Scope->getScopeNode())
308 auto *DS = Scope->getScopeNode();
310 assert((Scope->getInlinedAt() || !isa<DISubprogram>(DS)) &&
311 "Only handle inlined subprograms here, use "
312 "constructSubprogramScopeDIE for non-inlined "
315 SmallVector<DIE *, 8> Children;
317 // We try to create the scope DIE first, then the children DIEs. This will
318 // avoid creating un-used children then removing them later when we find out
319 // the scope DIE is null.
321 if (Scope->getParent() && isa<DISubprogram>(DS)) {
322 ScopeDIE = constructInlinedScopeDIE(Scope);
325 // We create children when the scope DIE is not null.
326 createScopeChildrenDIE(Scope, Children);
328 // Early exit when we know the scope DIE is going to be null.
329 if (DD->isLexicalScopeDIENull(Scope))
332 unsigned ChildScopeCount;
334 // We create children here when we know the scope DIE is not going to be
335 // null and the children will be added to the scope DIE.
336 createScopeChildrenDIE(Scope, Children, &ChildScopeCount);
338 // Skip imported directives in gmlt-like data.
339 if (!includeMinimalInlineScopes()) {
340 // There is no need to emit empty lexical block DIE.
341 for (const auto *IE : ImportedEntities[DS])
343 constructImportedEntityDIE(cast<DIImportedEntity>(IE)));
346 // If there are only other scopes as children, put them directly in the
347 // parent instead, as this scope would serve no purpose.
348 if (Children.size() == ChildScopeCount) {
349 FinalChildren.insert(FinalChildren.end(),
350 std::make_move_iterator(Children.begin()),
351 std::make_move_iterator(Children.end()));
354 ScopeDIE = constructLexicalScopeDIE(Scope);
355 assert(ScopeDIE && "Scope DIE should not be null.");
359 for (auto &I : Children)
360 ScopeDIE->addChild(std::move(I));
362 FinalChildren.push_back(std::move(ScopeDIE));
366 DwarfCompileUnit::addSectionDelta(DIE &Die, dwarf::Attribute Attribute,
367 const MCSymbol *Hi, const MCSymbol *Lo) {
368 return Die.addValue(DIEValueAllocator, Attribute,
369 DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
370 : dwarf::DW_FORM_data4,
371 new (DIEValueAllocator) DIEDelta(Hi, Lo));
374 void DwarfCompileUnit::addScopeRangeList(DIE &ScopeDIE,
375 SmallVector<RangeSpan, 2> Range) {
376 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
378 // Emit offset in .debug_range as a relocatable label. emitDIE will handle
379 // emitting it appropriately.
380 const MCSymbol *RangeSectionSym =
381 TLOF.getDwarfRangesSection()->getBeginSymbol();
383 RangeSpanList List(Asm->createTempSymbol("debug_ranges"), std::move(Range));
385 // Under fission, ranges are specified by constant offsets relative to the
386 // CU's DW_AT_GNU_ranges_base.
388 addSectionDelta(ScopeDIE, dwarf::DW_AT_ranges, List.getSym(),
391 addSectionLabel(ScopeDIE, dwarf::DW_AT_ranges, List.getSym(),
394 // Add the range list to the set of ranges to be emitted.
395 (Skeleton ? Skeleton : this)->CURangeLists.push_back(std::move(List));
398 void DwarfCompileUnit::attachRangesOrLowHighPC(
399 DIE &Die, SmallVector<RangeSpan, 2> Ranges) {
400 if (Ranges.size() == 1) {
401 const auto &single = Ranges.front();
402 attachLowHighPC(Die, single.getStart(), single.getEnd());
404 addScopeRangeList(Die, std::move(Ranges));
407 void DwarfCompileUnit::attachRangesOrLowHighPC(
408 DIE &Die, const SmallVectorImpl<InsnRange> &Ranges) {
409 SmallVector<RangeSpan, 2> List;
410 List.reserve(Ranges.size());
411 for (const InsnRange &R : Ranges)
412 List.push_back(RangeSpan(DD->getLabelBeforeInsn(R.first),
413 DD->getLabelAfterInsn(R.second)));
414 attachRangesOrLowHighPC(Die, std::move(List));
417 // This scope represents inlined body of a function. Construct DIE to
418 // represent this concrete inlined copy of the function.
419 DIE *DwarfCompileUnit::constructInlinedScopeDIE(LexicalScope *Scope) {
420 assert(Scope->getScopeNode());
421 auto *DS = Scope->getScopeNode();
422 auto *InlinedSP = getDISubprogram(DS);
423 // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram
424 // was inlined from another compile unit.
425 DIE *OriginDIE = DU->getAbstractSPDies()[InlinedSP];
426 assert(OriginDIE && "Unable to find original DIE for an inlined subprogram.");
428 auto ScopeDIE = DIE::get(DIEValueAllocator, dwarf::DW_TAG_inlined_subroutine);
429 addDIEEntry(*ScopeDIE, dwarf::DW_AT_abstract_origin, *OriginDIE);
431 attachRangesOrLowHighPC(*ScopeDIE, Scope->getRanges());
433 // Add the call site information to the DIE.
434 const DILocation *IA = Scope->getInlinedAt();
435 addUInt(*ScopeDIE, dwarf::DW_AT_call_file, None,
436 getOrCreateSourceID(IA->getFilename(), IA->getDirectory()));
437 addUInt(*ScopeDIE, dwarf::DW_AT_call_line, None, IA->getLine());
438 if (IA->getDiscriminator() && DD->getDwarfVersion() >= 4)
439 addUInt(*ScopeDIE, dwarf::DW_AT_GNU_discriminator, None,
440 IA->getDiscriminator());
442 // Add name to the name table, we do this here because we're guaranteed
443 // to have concrete versions of our DW_TAG_inlined_subprogram nodes.
444 DD->addSubprogramNames(InlinedSP, *ScopeDIE);
449 // Construct new DW_TAG_lexical_block for this scope and attach
450 // DW_AT_low_pc/DW_AT_high_pc labels.
451 DIE *DwarfCompileUnit::constructLexicalScopeDIE(LexicalScope *Scope) {
452 if (DD->isLexicalScopeDIENull(Scope))
455 auto ScopeDIE = DIE::get(DIEValueAllocator, dwarf::DW_TAG_lexical_block);
456 if (Scope->isAbstractScope())
459 attachRangesOrLowHighPC(*ScopeDIE, Scope->getRanges());
464 /// constructVariableDIE - Construct a DIE for the given DbgVariable.
465 DIE *DwarfCompileUnit::constructVariableDIE(DbgVariable &DV, bool Abstract) {
466 auto D = constructVariableDIEImpl(DV, Abstract);
471 DIE *DwarfCompileUnit::constructVariableDIEImpl(const DbgVariable &DV,
473 // Define variable debug information entry.
474 auto VariableDie = DIE::get(DIEValueAllocator, DV.getTag());
477 applyVariableAttributes(DV, *VariableDie);
481 // Add variable address.
483 unsigned Offset = DV.getDebugLocListIndex();
485 addLocationList(*VariableDie, dwarf::DW_AT_location, Offset);
489 // Check if variable is described by a DBG_VALUE instruction.
490 if (const MachineInstr *DVInsn = DV.getMInsn()) {
491 assert(DVInsn->getNumOperands() == 4);
492 if (DVInsn->getOperand(0).isReg()) {
493 const MachineOperand RegOp = DVInsn->getOperand(0);
494 // If the second operand is an immediate, this is an indirect value.
495 if (DVInsn->getOperand(1).isImm()) {
496 MachineLocation Location(RegOp.getReg(),
497 DVInsn->getOperand(1).getImm());
498 addVariableAddress(DV, *VariableDie, Location);
499 } else if (RegOp.getReg())
500 addVariableAddress(DV, *VariableDie, MachineLocation(RegOp.getReg()));
501 } else if (DVInsn->getOperand(0).isImm()) {
502 // This variable is described by a single constant.
503 // Check whether it has a DIExpression.
504 auto *Expr = DV.getSingleExpression();
505 if (Expr && Expr->getNumElements()) {
506 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
507 DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc);
508 // If there is an expression, emit raw unsigned bytes.
509 DwarfExpr.addFragmentOffset(Expr);
510 DwarfExpr.AddUnsignedConstant(DVInsn->getOperand(0).getImm());
511 DwarfExpr.AddExpression(Expr);
512 addBlock(*VariableDie, dwarf::DW_AT_location, DwarfExpr.finalize());
514 addConstantValue(*VariableDie, DVInsn->getOperand(0), DV.getType());
515 } else if (DVInsn->getOperand(0).isFPImm())
516 addConstantFPValue(*VariableDie, DVInsn->getOperand(0));
517 else if (DVInsn->getOperand(0).isCImm())
518 addConstantValue(*VariableDie, DVInsn->getOperand(0).getCImm(),
524 // .. else use frame index.
525 if (DV.getFrameIndex().empty())
528 auto Expr = DV.getExpression().begin();
529 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
530 DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc);
531 for (auto FI : DV.getFrameIndex()) {
532 unsigned FrameReg = 0;
533 const TargetFrameLowering *TFI = Asm->MF->getSubtarget().getFrameLowering();
534 int Offset = TFI->getFrameIndexReference(*Asm->MF, FI, FrameReg);
535 assert(Expr != DV.getExpression().end() && "Wrong number of expressions");
536 DwarfExpr.addFragmentOffset(*Expr);
537 DwarfExpr.AddMachineRegIndirect(*Asm->MF->getSubtarget().getRegisterInfo(),
539 DwarfExpr.AddExpression(*Expr);
542 addBlock(*VariableDie, dwarf::DW_AT_location, DwarfExpr.finalize());
547 DIE *DwarfCompileUnit::constructVariableDIE(DbgVariable &DV,
548 const LexicalScope &Scope,
549 DIE *&ObjectPointer) {
550 auto Var = constructVariableDIE(DV, Scope.isAbstractScope());
551 if (DV.isObjectPointer())
556 DIE *DwarfCompileUnit::createScopeChildrenDIE(LexicalScope *Scope,
557 SmallVectorImpl<DIE *> &Children,
558 unsigned *ChildScopeCount) {
559 DIE *ObjectPointer = nullptr;
561 for (DbgVariable *DV : DU->getScopeVariables().lookup(Scope))
562 Children.push_back(constructVariableDIE(*DV, *Scope, ObjectPointer));
564 unsigned ChildCountWithoutScopes = Children.size();
566 for (LexicalScope *LS : Scope->getChildren())
567 constructScopeDIE(LS, Children);
570 *ChildScopeCount = Children.size() - ChildCountWithoutScopes;
572 return ObjectPointer;
575 void DwarfCompileUnit::constructSubprogramScopeDIE(const DISubprogram *Sub, LexicalScope *Scope) {
576 DIE &ScopeDIE = updateSubprogramScopeDIE(Sub);
579 assert(!Scope->getInlinedAt());
580 assert(!Scope->isAbstractScope());
581 // Collect lexical scope children first.
582 // ObjectPointer might be a local (non-argument) local variable if it's a
583 // block's synthetic this pointer.
584 if (DIE *ObjectPointer = createAndAddScopeChildren(Scope, ScopeDIE))
585 addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer);
588 // If this is a variadic function, add an unspecified parameter.
589 DITypeRefArray FnArgs = Sub->getType()->getTypeArray();
591 // If we have a single element of null, it is a function that returns void.
592 // If we have more than one elements and the last one is null, it is a
593 // variadic function.
594 if (FnArgs.size() > 1 && !FnArgs[FnArgs.size() - 1] &&
595 !includeMinimalInlineScopes())
597 DIE::get(DIEValueAllocator, dwarf::DW_TAG_unspecified_parameters));
600 DIE *DwarfCompileUnit::createAndAddScopeChildren(LexicalScope *Scope,
602 // We create children when the scope DIE is not null.
603 SmallVector<DIE *, 8> Children;
604 DIE *ObjectPointer = createScopeChildrenDIE(Scope, Children);
607 for (auto &I : Children)
608 ScopeDIE.addChild(std::move(I));
610 return ObjectPointer;
613 void DwarfCompileUnit::constructAbstractSubprogramScopeDIE(
614 LexicalScope *Scope) {
615 DIE *&AbsDef = DU->getAbstractSPDies()[Scope->getScopeNode()];
619 auto *SP = cast<DISubprogram>(Scope->getScopeNode());
623 if (includeMinimalInlineScopes())
624 ContextDIE = &getUnitDie();
625 // Some of this is duplicated from DwarfUnit::getOrCreateSubprogramDIE, with
626 // the important distinction that the debug node is not associated with the
627 // DIE (since the debug node will be associated with the concrete DIE, if
628 // any). It could be refactored to some common utility function.
629 else if (auto *SPDecl = SP->getDeclaration()) {
630 ContextDIE = &getUnitDie();
631 getOrCreateSubprogramDIE(SPDecl);
633 ContextDIE = getOrCreateContextDIE(resolve(SP->getScope()));
635 // Passing null as the associated node because the abstract definition
636 // shouldn't be found by lookup.
637 AbsDef = &createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, nullptr);
638 applySubprogramAttributesToDefinition(SP, *AbsDef);
640 if (!includeMinimalInlineScopes())
641 addUInt(*AbsDef, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
642 if (DIE *ObjectPointer = createAndAddScopeChildren(Scope, *AbsDef))
643 addDIEEntry(*AbsDef, dwarf::DW_AT_object_pointer, *ObjectPointer);
646 DIE *DwarfCompileUnit::constructImportedEntityDIE(
647 const DIImportedEntity *Module) {
648 DIE *IMDie = DIE::get(DIEValueAllocator, (dwarf::Tag)Module->getTag());
649 insertDIE(Module, IMDie);
651 auto *Entity = resolve(Module->getEntity());
652 if (auto *NS = dyn_cast<DINamespace>(Entity))
653 EntityDie = getOrCreateNameSpace(NS);
654 else if (auto *M = dyn_cast<DIModule>(Entity))
655 EntityDie = getOrCreateModule(M);
656 else if (auto *SP = dyn_cast<DISubprogram>(Entity))
657 EntityDie = getOrCreateSubprogramDIE(SP);
658 else if (auto *T = dyn_cast<DIType>(Entity))
659 EntityDie = getOrCreateTypeDIE(T);
660 else if (auto *GV = dyn_cast<DIGlobalVariable>(Entity))
661 EntityDie = getOrCreateGlobalVariableDIE(GV, {});
663 EntityDie = getDIE(Entity);
665 addSourceLine(*IMDie, Module->getLine(), Module->getScope()->getFilename(),
666 Module->getScope()->getDirectory());
667 addDIEEntry(*IMDie, dwarf::DW_AT_import, *EntityDie);
668 StringRef Name = Module->getName();
670 addString(*IMDie, dwarf::DW_AT_name, Name);
675 void DwarfCompileUnit::finishSubprogramDefinition(const DISubprogram *SP) {
677 if (DIE *AbsSPDIE = DU->getAbstractSPDies().lookup(SP)) {
679 // If this subprogram has an abstract definition, reference that
680 addDIEEntry(*D, dwarf::DW_AT_abstract_origin, *AbsSPDIE);
682 assert(D || includeMinimalInlineScopes());
684 // And attach the attributes
685 applySubprogramAttributesToDefinition(SP, *D);
689 void DwarfCompileUnit::emitHeader(bool UseOffsets) {
690 // Don't bother labeling the .dwo unit, as its offset isn't used.
692 LabelBegin = Asm->createTempSymbol("cu_begin");
693 Asm->OutStreamer->EmitLabel(LabelBegin);
696 DwarfUnit::emitHeader(UseOffsets);
699 /// addGlobalName - Add a new global name to the compile unit.
700 void DwarfCompileUnit::addGlobalName(StringRef Name, DIE &Die,
701 const DIScope *Context) {
702 if (includeMinimalInlineScopes())
704 std::string FullName = getParentContextString(Context) + Name.str();
705 GlobalNames[FullName] = &Die;
708 /// Add a new global type to the unit.
709 void DwarfCompileUnit::addGlobalType(const DIType *Ty, const DIE &Die,
710 const DIScope *Context) {
711 if (includeMinimalInlineScopes())
713 std::string FullName = getParentContextString(Context) + Ty->getName().str();
714 GlobalTypes[FullName] = &Die;
717 /// addVariableAddress - Add DW_AT_location attribute for a
718 /// DbgVariable based on provided MachineLocation.
719 void DwarfCompileUnit::addVariableAddress(const DbgVariable &DV, DIE &Die,
720 MachineLocation Location) {
721 if (DV.hasComplexAddress())
722 addComplexAddress(DV, Die, dwarf::DW_AT_location, Location);
723 else if (DV.isBlockByrefVariable())
724 addBlockByrefAddress(DV, Die, dwarf::DW_AT_location, Location);
726 addAddress(Die, dwarf::DW_AT_location, Location);
729 /// Add an address attribute to a die based on the location provided.
730 void DwarfCompileUnit::addAddress(DIE &Die, dwarf::Attribute Attribute,
731 const MachineLocation &Location) {
732 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
733 DIEDwarfExpression Expr(*Asm, *this, *Loc);
736 if (Location.isReg())
737 validReg = Expr.AddMachineReg(*Asm->MF->getSubtarget().getRegisterInfo(),
741 Expr.AddMachineRegIndirect(*Asm->MF->getSubtarget().getRegisterInfo(),
742 Location.getReg(), Location.getOffset());
747 // Now attach the location information to the DIE.
748 addBlock(Die, Attribute, Expr.finalize());
751 /// Start with the address based on the location provided, and generate the
752 /// DWARF information necessary to find the actual variable given the extra
753 /// address information encoded in the DbgVariable, starting from the starting
754 /// location. Add the DWARF information to the die.
755 void DwarfCompileUnit::addComplexAddress(const DbgVariable &DV, DIE &Die,
756 dwarf::Attribute Attribute,
757 const MachineLocation &Location) {
758 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
759 DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc);
760 const DIExpression *Expr = DV.getSingleExpression();
761 DIExpressionCursor ExprCursor(Expr);
762 const TargetRegisterInfo &TRI = *Asm->MF->getSubtarget().getRegisterInfo();
763 auto Reg = Location.getReg();
764 DwarfExpr.addFragmentOffset(Expr);
767 ? DwarfExpr.AddMachineRegIndirect(TRI, Reg, Location.getOffset())
768 : DwarfExpr.AddMachineRegExpression(TRI, ExprCursor, Reg);
773 DwarfExpr.AddExpression(std::move(ExprCursor));
775 // Now attach the location information to the DIE.
776 addBlock(Die, Attribute, Loc);
779 /// Add a Dwarf loclistptr attribute data and value.
780 void DwarfCompileUnit::addLocationList(DIE &Die, dwarf::Attribute Attribute,
782 dwarf::Form Form = DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
783 : dwarf::DW_FORM_data4;
784 Die.addValue(DIEValueAllocator, Attribute, Form, DIELocList(Index));
787 void DwarfCompileUnit::applyVariableAttributes(const DbgVariable &Var,
789 StringRef Name = Var.getName();
791 addString(VariableDie, dwarf::DW_AT_name, Name);
792 const auto *DIVar = Var.getVariable();
794 if (uint32_t AlignInBytes = DIVar->getAlignInBytes())
795 addUInt(VariableDie, dwarf::DW_AT_alignment, dwarf::DW_FORM_udata,
798 addSourceLine(VariableDie, DIVar);
799 addType(VariableDie, Var.getType());
800 if (Var.isArtificial())
801 addFlag(VariableDie, dwarf::DW_AT_artificial);
804 /// Add a Dwarf expression attribute data and value.
805 void DwarfCompileUnit::addExpr(DIELoc &Die, dwarf::Form Form,
806 const MCExpr *Expr) {
807 Die.addValue(DIEValueAllocator, (dwarf::Attribute)0, Form, DIEExpr(Expr));
810 void DwarfCompileUnit::applySubprogramAttributesToDefinition(
811 const DISubprogram *SP, DIE &SPDie) {
812 auto *SPDecl = SP->getDeclaration();
813 auto *Context = resolve(SPDecl ? SPDecl->getScope() : SP->getScope());
814 applySubprogramAttributes(SP, SPDie, includeMinimalInlineScopes());
815 addGlobalName(SP->getName(), SPDie, Context);
818 bool DwarfCompileUnit::isDwoUnit() const {
819 return DD->useSplitDwarf() && Skeleton;
822 bool DwarfCompileUnit::includeMinimalInlineScopes() const {
823 return getCUNode()->getEmissionKind() == DICompileUnit::LineTablesOnly ||
824 (DD->useSplitDwarf() && !Skeleton);
826 } // end llvm namespace