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(UID, dwarf::DW_TAG_compile_unit, Node, A, DW, DWU),
23 Skeleton(nullptr), BaseAddress(nullptr) {
24 insertDIE(Node, &getUnitDie());
27 /// addLabelAddress - Add a dwarf label attribute data and value using
28 /// DW_FORM_addr or DW_FORM_GNU_addr_index.
30 void DwarfCompileUnit::addLabelAddress(DIE &Die, dwarf::Attribute Attribute,
31 const MCSymbol *Label) {
33 // Don't use the address pool in non-fission or in the skeleton unit itself.
34 // FIXME: Once GDB supports this, it's probably worthwhile using the address
35 // pool from the skeleton - maybe even in non-fission (possibly fewer
36 // relocations by sharing them in the pool, but we have other ideas about how
37 // to reduce the number of relocations as well/instead).
38 if (!DD->useSplitDwarf() || !Skeleton)
39 return addLocalLabelAddress(Die, Attribute, Label);
42 DD->addArangeLabel(SymbolCU(this, Label));
44 unsigned idx = DD->getAddressPool().getIndex(Label);
45 Die.addValue(DIEValueAllocator, Attribute, dwarf::DW_FORM_GNU_addr_index,
49 void DwarfCompileUnit::addLocalLabelAddress(DIE &Die,
50 dwarf::Attribute Attribute,
51 const MCSymbol *Label) {
53 DD->addArangeLabel(SymbolCU(this, Label));
56 Die.addValue(DIEValueAllocator, Attribute, dwarf::DW_FORM_addr,
59 Die.addValue(DIEValueAllocator, Attribute, dwarf::DW_FORM_addr,
63 unsigned DwarfCompileUnit::getOrCreateSourceID(StringRef FileName,
65 // If we print assembly, we can't separate .file entries according to
66 // compile units. Thus all files will belong to the default compile unit.
68 // FIXME: add a better feature test than hasRawTextSupport. Even better,
69 // extend .file to support this.
70 return Asm->OutStreamer->EmitDwarfFileDirective(
72 Asm->OutStreamer->hasRawTextSupport() ? 0 : getUniqueID());
75 // Return const expression if value is a GEP to access merged global
77 // i8* getelementptr ({ i8, i8, i8, i8 }* @_MergedGlobals, i32 0, i32 0)
78 static const ConstantExpr *getMergedGlobalExpr(const Value *V) {
79 const ConstantExpr *CE = dyn_cast_or_null<ConstantExpr>(V);
80 if (!CE || CE->getNumOperands() != 3 ||
81 CE->getOpcode() != Instruction::GetElementPtr)
84 // First operand points to a global struct.
85 Value *Ptr = CE->getOperand(0);
86 if (!isa<GlobalValue>(Ptr) ||
87 !isa<StructType>(cast<PointerType>(Ptr->getType())->getElementType()))
90 // Second operand is zero.
91 const ConstantInt *CI = dyn_cast_or_null<ConstantInt>(CE->getOperand(1));
92 if (!CI || !CI->isZero())
95 // Third operand is offset.
96 if (!isa<ConstantInt>(CE->getOperand(2)))
102 /// getOrCreateGlobalVariableDIE - get or create global variable DIE.
103 DIE *DwarfCompileUnit::getOrCreateGlobalVariableDIE(
104 const DIGlobalVariable *GV) {
105 // Check for pre-existence.
106 if (DIE *Die = getDIE(GV))
111 auto *GVContext = GV->getScope();
112 auto *GTy = DD->resolve(GV->getType());
114 // Construct the context before querying for the existence of the DIE in
115 // case such construction creates the DIE.
116 DIE *ContextDIE = getOrCreateContextDIE(GVContext);
119 DIE *VariableDIE = &createAndAddDIE(GV->getTag(), *ContextDIE, GV);
120 DIScope *DeclContext;
121 if (auto *SDMDecl = GV->getStaticDataMemberDeclaration()) {
122 DeclContext = resolve(SDMDecl->getScope());
123 assert(SDMDecl->isStaticMember() && "Expected static member decl");
124 assert(GV->isDefinition());
125 // We need the declaration DIE that is in the static member's class.
126 DIE *VariableSpecDIE = getOrCreateStaticMemberDIE(SDMDecl);
127 addDIEEntry(*VariableDIE, dwarf::DW_AT_specification, *VariableSpecDIE);
129 DeclContext = GV->getScope();
130 // Add name and type.
131 addString(*VariableDIE, dwarf::DW_AT_name, GV->getDisplayName());
132 addType(*VariableDIE, GTy);
135 if (!GV->isLocalToUnit())
136 addFlag(*VariableDIE, dwarf::DW_AT_external);
138 // Add line number info.
139 addSourceLine(*VariableDIE, GV);
142 if (!GV->isDefinition())
143 addFlag(*VariableDIE, dwarf::DW_AT_declaration);
145 addGlobalName(GV->getName(), *VariableDIE, DeclContext);
148 bool addToAccelTable = false;
149 if (auto *Global = dyn_cast_or_null<GlobalVariable>(GV->getVariable())) {
150 addToAccelTable = true;
151 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
152 const MCSymbol *Sym = Asm->getSymbol(Global);
153 if (Global->isThreadLocal()) {
154 if (Asm->TM.Options.EmulatedTLS) {
155 // TODO: add debug info for emulated thread local mode.
157 // FIXME: Make this work with -gsplit-dwarf.
158 unsigned PointerSize = Asm->getDataLayout().getPointerSize();
159 assert((PointerSize == 4 || PointerSize == 8) &&
160 "Add support for other sizes if necessary");
161 // Based on GCC's support for TLS:
162 if (!DD->useSplitDwarf()) {
163 // 1) Start with a constNu of the appropriate pointer size
164 addUInt(*Loc, dwarf::DW_FORM_data1,
165 PointerSize == 4 ? dwarf::DW_OP_const4u : dwarf::DW_OP_const8u);
166 // 2) containing the (relocated) offset of the TLS variable
167 // within the module's TLS block.
168 addExpr(*Loc, dwarf::DW_FORM_udata,
169 Asm->getObjFileLowering().getDebugThreadLocalSymbol(Sym));
171 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_GNU_const_index);
172 addUInt(*Loc, dwarf::DW_FORM_udata,
173 DD->getAddressPool().getIndex(Sym, /* TLS */ true));
175 // 3) followed by an OP to make the debugger do a TLS lookup.
176 addUInt(*Loc, dwarf::DW_FORM_data1,
177 DD->useGNUTLSOpcode() ? dwarf::DW_OP_GNU_push_tls_address
178 : dwarf::DW_OP_form_tls_address);
181 DD->addArangeLabel(SymbolCU(this, Sym));
182 addOpAddress(*Loc, Sym);
185 addBlock(*VariableDIE, dwarf::DW_AT_location, Loc);
186 addLinkageName(*VariableDIE, GV->getLinkageName());
187 } else if (const ConstantInt *CI =
188 dyn_cast_or_null<ConstantInt>(GV->getVariable())) {
189 addConstantValue(*VariableDIE, CI, GTy);
190 } else if (const ConstantExpr *CE = getMergedGlobalExpr(GV->getVariable())) {
191 addToAccelTable = true;
192 // GV is a merged global.
193 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
194 Value *Ptr = CE->getOperand(0);
195 MCSymbol *Sym = Asm->getSymbol(cast<GlobalValue>(Ptr));
196 DD->addArangeLabel(SymbolCU(this, Sym));
197 addOpAddress(*Loc, Sym);
198 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
199 SmallVector<Value *, 3> Idx(CE->op_begin() + 1, CE->op_end());
200 addUInt(*Loc, dwarf::DW_FORM_udata,
201 Asm->getDataLayout().getIndexedOffset(Ptr->getType(), Idx));
202 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_plus);
203 addBlock(*VariableDIE, dwarf::DW_AT_location, Loc);
206 if (addToAccelTable) {
207 DD->addAccelName(GV->getName(), *VariableDIE);
209 // If the linkage name is different than the name, go ahead and output
210 // that as well into the name table.
211 if (GV->getLinkageName() != "" && GV->getName() != GV->getLinkageName())
212 DD->addAccelName(GV->getLinkageName(), *VariableDIE);
218 void DwarfCompileUnit::addRange(RangeSpan Range) {
219 bool SameAsPrevCU = this == DD->getPrevCU();
221 // If we have no current ranges just add the range and return, otherwise,
222 // check the current section and CU against the previous section and CU we
223 // emitted into and the subprogram was contained within. If these are the
224 // same then extend our current range, otherwise add this as a new range.
225 if (CURanges.empty() || !SameAsPrevCU ||
226 (&CURanges.back().getEnd()->getSection() !=
227 &Range.getEnd()->getSection())) {
228 CURanges.push_back(Range);
232 CURanges.back().setEnd(Range.getEnd());
236 DwarfCompileUnit::addSectionLabel(DIE &Die, dwarf::Attribute Attribute,
237 const MCSymbol *Label, const MCSymbol *Sec) {
238 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
239 return addLabel(Die, Attribute,
240 DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
241 : dwarf::DW_FORM_data4,
243 return addSectionDelta(Die, Attribute, Label, Sec);
246 void DwarfCompileUnit::initStmtList() {
247 // Define start line table label for each Compile Unit.
248 MCSymbol *LineTableStartSym =
249 Asm->OutStreamer->getDwarfLineTableSymbol(getUniqueID());
251 // DW_AT_stmt_list is a offset of line number information for this
252 // compile unit in debug_line section. For split dwarf this is
253 // left in the skeleton CU and so not included.
254 // The line table entries are not always emitted in assembly, so it
255 // is not okay to use line_table_start here.
256 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
258 addSectionLabel(UnitDie, dwarf::DW_AT_stmt_list, LineTableStartSym,
259 TLOF.getDwarfLineSection()->getBeginSymbol());
262 void DwarfCompileUnit::applyStmtList(DIE &D) {
263 D.addValue(DIEValueAllocator, *StmtListValue);
266 void DwarfCompileUnit::attachLowHighPC(DIE &D, const MCSymbol *Begin,
267 const MCSymbol *End) {
268 assert(Begin && "Begin label should not be null!");
269 assert(End && "End label should not be null!");
270 assert(Begin->isDefined() && "Invalid starting label");
271 assert(End->isDefined() && "Invalid end label");
273 addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
274 if (DD->getDwarfVersion() < 4)
275 addLabelAddress(D, dwarf::DW_AT_high_pc, End);
277 addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
280 // Find DIE for the given subprogram and attach appropriate DW_AT_low_pc
281 // and DW_AT_high_pc attributes. If there are global variables in this
282 // scope then create and insert DIEs for these variables.
283 DIE &DwarfCompileUnit::updateSubprogramScopeDIE(const DISubprogram *SP) {
284 DIE *SPDie = getOrCreateSubprogramDIE(SP, includeMinimalInlineScopes());
286 attachLowHighPC(*SPDie, Asm->getFunctionBegin(), Asm->getFunctionEnd());
287 if (!DD->getCurrentFunction()->getTarget().Options.DisableFramePointerElim(
288 *DD->getCurrentFunction()))
289 addFlag(*SPDie, dwarf::DW_AT_APPLE_omit_frame_ptr);
291 // Only include DW_AT_frame_base in full debug info
292 if (!includeMinimalInlineScopes()) {
293 const TargetRegisterInfo *RI = Asm->MF->getSubtarget().getRegisterInfo();
294 MachineLocation Location(RI->getFrameRegister(*Asm->MF));
295 if (RI->isPhysicalRegister(Location.getReg()))
296 addAddress(*SPDie, dwarf::DW_AT_frame_base, Location);
299 // Add name to the name table, we do this here because we're guaranteed
300 // to have concrete versions of our DW_TAG_subprogram nodes.
301 DD->addSubprogramNames(SP, *SPDie);
306 // Construct a DIE for this scope.
307 void DwarfCompileUnit::constructScopeDIE(
308 LexicalScope *Scope, SmallVectorImpl<DIE *> &FinalChildren) {
309 if (!Scope || !Scope->getScopeNode())
312 auto *DS = Scope->getScopeNode();
314 assert((Scope->getInlinedAt() || !isa<DISubprogram>(DS)) &&
315 "Only handle inlined subprograms here, use "
316 "constructSubprogramScopeDIE for non-inlined "
319 SmallVector<DIE *, 8> Children;
321 // We try to create the scope DIE first, then the children DIEs. This will
322 // avoid creating un-used children then removing them later when we find out
323 // the scope DIE is null.
325 if (Scope->getParent() && isa<DISubprogram>(DS)) {
326 ScopeDIE = constructInlinedScopeDIE(Scope);
329 // We create children when the scope DIE is not null.
330 createScopeChildrenDIE(Scope, Children);
332 // Early exit when we know the scope DIE is going to be null.
333 if (DD->isLexicalScopeDIENull(Scope))
336 unsigned ChildScopeCount;
338 // We create children here when we know the scope DIE is not going to be
339 // null and the children will be added to the scope DIE.
340 createScopeChildrenDIE(Scope, Children, &ChildScopeCount);
342 // Skip imported directives in gmlt-like data.
343 if (!includeMinimalInlineScopes()) {
344 // There is no need to emit empty lexical block DIE.
345 for (const auto *IE : ImportedEntities[DS])
347 constructImportedEntityDIE(cast<DIImportedEntity>(IE)));
350 // If there are only other scopes as children, put them directly in the
351 // parent instead, as this scope would serve no purpose.
352 if (Children.size() == ChildScopeCount) {
353 FinalChildren.insert(FinalChildren.end(),
354 std::make_move_iterator(Children.begin()),
355 std::make_move_iterator(Children.end()));
358 ScopeDIE = constructLexicalScopeDIE(Scope);
359 assert(ScopeDIE && "Scope DIE should not be null.");
363 for (auto &I : Children)
364 ScopeDIE->addChild(std::move(I));
366 FinalChildren.push_back(std::move(ScopeDIE));
370 DwarfCompileUnit::addSectionDelta(DIE &Die, dwarf::Attribute Attribute,
371 const MCSymbol *Hi, const MCSymbol *Lo) {
372 return Die.addValue(DIEValueAllocator, Attribute,
373 DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
374 : dwarf::DW_FORM_data4,
375 new (DIEValueAllocator) DIEDelta(Hi, Lo));
378 void DwarfCompileUnit::addScopeRangeList(DIE &ScopeDIE,
379 SmallVector<RangeSpan, 2> Range) {
380 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
382 // Emit offset in .debug_range as a relocatable label. emitDIE will handle
383 // emitting it appropriately.
384 const MCSymbol *RangeSectionSym =
385 TLOF.getDwarfRangesSection()->getBeginSymbol();
387 RangeSpanList List(Asm->createTempSymbol("debug_ranges"), std::move(Range));
389 // Under fission, ranges are specified by constant offsets relative to the
390 // CU's DW_AT_GNU_ranges_base.
392 addSectionDelta(ScopeDIE, dwarf::DW_AT_ranges, List.getSym(),
395 addSectionLabel(ScopeDIE, dwarf::DW_AT_ranges, List.getSym(),
398 // Add the range list to the set of ranges to be emitted.
399 (Skeleton ? Skeleton : this)->CURangeLists.push_back(std::move(List));
402 void DwarfCompileUnit::attachRangesOrLowHighPC(
403 DIE &Die, SmallVector<RangeSpan, 2> Ranges) {
404 if (Ranges.size() == 1) {
405 const auto &single = Ranges.front();
406 attachLowHighPC(Die, single.getStart(), single.getEnd());
408 addScopeRangeList(Die, std::move(Ranges));
411 void DwarfCompileUnit::attachRangesOrLowHighPC(
412 DIE &Die, const SmallVectorImpl<InsnRange> &Ranges) {
413 SmallVector<RangeSpan, 2> List;
414 List.reserve(Ranges.size());
415 for (const InsnRange &R : Ranges)
416 List.push_back(RangeSpan(DD->getLabelBeforeInsn(R.first),
417 DD->getLabelAfterInsn(R.second)));
418 attachRangesOrLowHighPC(Die, std::move(List));
421 // This scope represents inlined body of a function. Construct DIE to
422 // represent this concrete inlined copy of the function.
423 DIE *DwarfCompileUnit::constructInlinedScopeDIE(LexicalScope *Scope) {
424 assert(Scope->getScopeNode());
425 auto *DS = Scope->getScopeNode();
426 auto *InlinedSP = getDISubprogram(DS);
427 // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram
428 // was inlined from another compile unit.
429 DIE *OriginDIE = DU->getAbstractSPDies()[InlinedSP];
430 assert(OriginDIE && "Unable to find original DIE for an inlined subprogram.");
432 auto ScopeDIE = DIE::get(DIEValueAllocator, dwarf::DW_TAG_inlined_subroutine);
433 addDIEEntry(*ScopeDIE, dwarf::DW_AT_abstract_origin, *OriginDIE);
435 attachRangesOrLowHighPC(*ScopeDIE, Scope->getRanges());
437 // Add the call site information to the DIE.
438 const DILocation *IA = Scope->getInlinedAt();
439 addUInt(*ScopeDIE, dwarf::DW_AT_call_file, None,
440 getOrCreateSourceID(IA->getFilename(), IA->getDirectory()));
441 addUInt(*ScopeDIE, dwarf::DW_AT_call_line, None, IA->getLine());
443 // Add name to the name table, we do this here because we're guaranteed
444 // to have concrete versions of our DW_TAG_inlined_subprogram nodes.
445 DD->addSubprogramNames(InlinedSP, *ScopeDIE);
450 // Construct new DW_TAG_lexical_block for this scope and attach
451 // DW_AT_low_pc/DW_AT_high_pc labels.
452 DIE *DwarfCompileUnit::constructLexicalScopeDIE(LexicalScope *Scope) {
453 if (DD->isLexicalScopeDIENull(Scope))
456 auto ScopeDIE = DIE::get(DIEValueAllocator, dwarf::DW_TAG_lexical_block);
457 if (Scope->isAbstractScope())
460 attachRangesOrLowHighPC(*ScopeDIE, Scope->getRanges());
465 /// constructVariableDIE - Construct a DIE for the given DbgVariable.
466 DIE *DwarfCompileUnit::constructVariableDIE(DbgVariable &DV, bool Abstract) {
467 auto D = constructVariableDIEImpl(DV, Abstract);
472 DIE *DwarfCompileUnit::constructVariableDIEImpl(const DbgVariable &DV,
474 // Define variable debug information entry.
475 auto VariableDie = DIE::get(DIEValueAllocator, DV.getTag());
478 applyVariableAttributes(DV, *VariableDie);
482 // Add variable address.
484 unsigned Offset = DV.getDebugLocListIndex();
486 addLocationList(*VariableDie, dwarf::DW_AT_location, Offset);
490 // Check if variable is described by a DBG_VALUE instruction.
491 if (const MachineInstr *DVInsn = DV.getMInsn()) {
492 assert(DVInsn->getNumOperands() == 4);
493 if (DVInsn->getOperand(0).isReg()) {
494 const MachineOperand RegOp = DVInsn->getOperand(0);
495 // If the second operand is an immediate, this is an indirect value.
496 if (DVInsn->getOperand(1).isImm()) {
497 MachineLocation Location(RegOp.getReg(),
498 DVInsn->getOperand(1).getImm());
499 addVariableAddress(DV, *VariableDie, Location);
500 } else if (RegOp.getReg())
501 addVariableAddress(DV, *VariableDie, MachineLocation(RegOp.getReg()));
502 } else if (DVInsn->getOperand(0).isImm())
503 addConstantValue(*VariableDie, DVInsn->getOperand(0), DV.getType());
504 else if (DVInsn->getOperand(0).isFPImm())
505 addConstantFPValue(*VariableDie, DVInsn->getOperand(0));
506 else if (DVInsn->getOperand(0).isCImm())
507 addConstantValue(*VariableDie, DVInsn->getOperand(0).getCImm(),
513 // .. else use frame index.
514 if (DV.getFrameIndex().empty())
517 auto Expr = DV.getExpression().begin();
518 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
519 DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc);
520 for (auto FI : DV.getFrameIndex()) {
521 unsigned FrameReg = 0;
522 const TargetFrameLowering *TFI = Asm->MF->getSubtarget().getFrameLowering();
523 int Offset = TFI->getFrameIndexReference(*Asm->MF, FI, FrameReg);
524 assert(Expr != DV.getExpression().end() &&
525 "Wrong number of expressions");
526 DwarfExpr.AddMachineRegIndirect(FrameReg, Offset);
527 DwarfExpr.AddExpression((*Expr)->expr_op_begin(), (*Expr)->expr_op_end());
530 addBlock(*VariableDie, dwarf::DW_AT_location, Loc);
535 DIE *DwarfCompileUnit::constructVariableDIE(DbgVariable &DV,
536 const LexicalScope &Scope,
537 DIE *&ObjectPointer) {
538 auto Var = constructVariableDIE(DV, Scope.isAbstractScope());
539 if (DV.isObjectPointer())
544 DIE *DwarfCompileUnit::createScopeChildrenDIE(LexicalScope *Scope,
545 SmallVectorImpl<DIE *> &Children,
546 unsigned *ChildScopeCount) {
547 DIE *ObjectPointer = nullptr;
549 for (DbgVariable *DV : DU->getScopeVariables().lookup(Scope))
550 Children.push_back(constructVariableDIE(*DV, *Scope, ObjectPointer));
552 unsigned ChildCountWithoutScopes = Children.size();
554 for (LexicalScope *LS : Scope->getChildren())
555 constructScopeDIE(LS, Children);
558 *ChildScopeCount = Children.size() - ChildCountWithoutScopes;
560 return ObjectPointer;
563 void DwarfCompileUnit::constructSubprogramScopeDIE(LexicalScope *Scope) {
564 assert(Scope && Scope->getScopeNode());
565 assert(!Scope->getInlinedAt());
566 assert(!Scope->isAbstractScope());
567 auto *Sub = cast<DISubprogram>(Scope->getScopeNode());
569 DD->getProcessedSPNodes().insert(Sub);
571 DIE &ScopeDIE = updateSubprogramScopeDIE(Sub);
573 // If this is a variadic function, add an unspecified parameter.
574 DITypeRefArray FnArgs = Sub->getType()->getTypeArray();
576 // Collect lexical scope children first.
577 // ObjectPointer might be a local (non-argument) local variable if it's a
578 // block's synthetic this pointer.
579 if (DIE *ObjectPointer = createAndAddScopeChildren(Scope, ScopeDIE))
580 addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer);
582 // If we have a single element of null, it is a function that returns void.
583 // If we have more than one elements and the last one is null, it is a
584 // variadic function.
585 if (FnArgs.size() > 1 && !FnArgs[FnArgs.size() - 1] &&
586 !includeMinimalInlineScopes())
588 DIE::get(DIEValueAllocator, dwarf::DW_TAG_unspecified_parameters));
591 DIE *DwarfCompileUnit::createAndAddScopeChildren(LexicalScope *Scope,
593 // We create children when the scope DIE is not null.
594 SmallVector<DIE *, 8> Children;
595 DIE *ObjectPointer = createScopeChildrenDIE(Scope, Children);
598 for (auto &I : Children)
599 ScopeDIE.addChild(std::move(I));
601 return ObjectPointer;
605 DwarfCompileUnit::constructAbstractSubprogramScopeDIE(LexicalScope *Scope) {
606 DIE *&AbsDef = DU->getAbstractSPDies()[Scope->getScopeNode()];
610 auto *SP = cast<DISubprogram>(Scope->getScopeNode());
614 if (includeMinimalInlineScopes())
615 ContextDIE = &getUnitDie();
616 // Some of this is duplicated from DwarfUnit::getOrCreateSubprogramDIE, with
617 // the important distinction that the debug node is not associated with the
618 // DIE (since the debug node will be associated with the concrete DIE, if
619 // any). It could be refactored to some common utility function.
620 else if (auto *SPDecl = SP->getDeclaration()) {
621 ContextDIE = &getUnitDie();
622 getOrCreateSubprogramDIE(SPDecl);
624 ContextDIE = getOrCreateContextDIE(resolve(SP->getScope()));
626 // Passing null as the associated node because the abstract definition
627 // shouldn't be found by lookup.
628 AbsDef = &createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, nullptr);
629 applySubprogramAttributesToDefinition(SP, *AbsDef);
631 if (!includeMinimalInlineScopes())
632 addUInt(*AbsDef, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
633 if (DIE *ObjectPointer = createAndAddScopeChildren(Scope, *AbsDef))
634 addDIEEntry(*AbsDef, dwarf::DW_AT_object_pointer, *ObjectPointer);
637 DIE *DwarfCompileUnit::constructImportedEntityDIE(
638 const DIImportedEntity *Module) {
639 DIE *IMDie = DIE::get(DIEValueAllocator, (dwarf::Tag)Module->getTag());
640 insertDIE(Module, IMDie);
642 auto *Entity = resolve(Module->getEntity());
643 if (auto *NS = dyn_cast<DINamespace>(Entity))
644 EntityDie = getOrCreateNameSpace(NS);
645 else if (auto *M = dyn_cast<DIModule>(Entity))
646 EntityDie = getOrCreateModule(M);
647 else if (auto *SP = dyn_cast<DISubprogram>(Entity))
648 EntityDie = getOrCreateSubprogramDIE(SP);
649 else if (auto *T = dyn_cast<DIType>(Entity))
650 EntityDie = getOrCreateTypeDIE(T);
651 else if (auto *GV = dyn_cast<DIGlobalVariable>(Entity))
652 EntityDie = getOrCreateGlobalVariableDIE(GV);
654 EntityDie = getDIE(Entity);
656 addSourceLine(*IMDie, Module->getLine(), Module->getScope()->getFilename(),
657 Module->getScope()->getDirectory());
658 addDIEEntry(*IMDie, dwarf::DW_AT_import, *EntityDie);
659 StringRef Name = Module->getName();
661 addString(*IMDie, dwarf::DW_AT_name, Name);
666 void DwarfCompileUnit::finishSubprogramDefinition(const DISubprogram *SP) {
668 if (DIE *AbsSPDIE = DU->getAbstractSPDies().lookup(SP)) {
670 // If this subprogram has an abstract definition, reference that
671 addDIEEntry(*D, dwarf::DW_AT_abstract_origin, *AbsSPDIE);
673 if (!D && !includeMinimalInlineScopes())
674 // Lazily construct the subprogram if we didn't see either concrete or
675 // inlined versions during codegen. (except in -gmlt ^ where we want
676 // to omit these entirely)
677 D = getOrCreateSubprogramDIE(SP);
679 // And attach the attributes
680 applySubprogramAttributesToDefinition(SP, *D);
683 void DwarfCompileUnit::collectDeadVariables(const DISubprogram *SP) {
684 assert(SP && "CU's subprogram list contains a non-subprogram");
685 assert(SP->isDefinition() &&
686 "CU's subprogram list contains a subprogram declaration");
687 auto Variables = SP->getVariables();
688 if (Variables.size() == 0)
691 DIE *SPDIE = DU->getAbstractSPDies().lookup(SP);
695 for (const DILocalVariable *DV : Variables) {
696 DbgVariable NewVar(DV, /* IA */ nullptr, DD);
697 auto VariableDie = constructVariableDIE(NewVar);
698 applyVariableAttributes(NewVar, *VariableDie);
699 SPDIE->addChild(std::move(VariableDie));
703 void DwarfCompileUnit::emitHeader(bool UseOffsets) {
704 // Don't bother labeling the .dwo unit, as its offset isn't used.
706 LabelBegin = Asm->createTempSymbol("cu_begin");
707 Asm->OutStreamer->EmitLabel(LabelBegin);
710 DwarfUnit::emitHeader(UseOffsets);
713 /// addGlobalName - Add a new global name to the compile unit.
714 void DwarfCompileUnit::addGlobalName(StringRef Name, DIE &Die,
715 const DIScope *Context) {
716 if (includeMinimalInlineScopes())
718 std::string FullName = getParentContextString(Context) + Name.str();
719 GlobalNames[FullName] = &Die;
722 /// Add a new global type to the unit.
723 void DwarfCompileUnit::addGlobalType(const DIType *Ty, const DIE &Die,
724 const DIScope *Context) {
725 if (includeMinimalInlineScopes())
727 std::string FullName = getParentContextString(Context) + Ty->getName().str();
728 GlobalTypes[FullName] = &Die;
731 /// addVariableAddress - Add DW_AT_location attribute for a
732 /// DbgVariable based on provided MachineLocation.
733 void DwarfCompileUnit::addVariableAddress(const DbgVariable &DV, DIE &Die,
734 MachineLocation Location) {
735 if (DV.hasComplexAddress())
736 addComplexAddress(DV, Die, dwarf::DW_AT_location, Location);
737 else if (DV.isBlockByrefVariable())
738 addBlockByrefAddress(DV, Die, dwarf::DW_AT_location, Location);
740 addAddress(Die, dwarf::DW_AT_location, Location);
743 /// Add an address attribute to a die based on the location provided.
744 void DwarfCompileUnit::addAddress(DIE &Die, dwarf::Attribute Attribute,
745 const MachineLocation &Location) {
746 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
749 if (Location.isReg())
750 validReg = addRegisterOpPiece(*Loc, Location.getReg());
752 validReg = addRegisterOffset(*Loc, Location.getReg(), Location.getOffset());
757 // Now attach the location information to the DIE.
758 addBlock(Die, Attribute, Loc);
761 /// Start with the address based on the location provided, and generate the
762 /// DWARF information necessary to find the actual variable given the extra
763 /// address information encoded in the DbgVariable, starting from the starting
764 /// location. Add the DWARF information to the die.
765 void DwarfCompileUnit::addComplexAddress(const DbgVariable &DV, DIE &Die,
766 dwarf::Attribute Attribute,
767 const MachineLocation &Location) {
768 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
769 DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc);
770 assert(DV.getExpression().size() == 1);
771 const DIExpression *Expr = DV.getExpression().back();
773 if (Location.getOffset()) {
774 ValidReg = DwarfExpr.AddMachineRegIndirect(Location.getReg(),
775 Location.getOffset());
777 DwarfExpr.AddExpression(Expr->expr_op_begin(), Expr->expr_op_end());
779 ValidReg = DwarfExpr.AddMachineRegExpression(Expr, Location.getReg());
781 // Now attach the location information to the DIE.
783 addBlock(Die, Attribute, Loc);
786 /// Add a Dwarf loclistptr attribute data and value.
787 void DwarfCompileUnit::addLocationList(DIE &Die, dwarf::Attribute Attribute,
789 dwarf::Form Form = DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
790 : dwarf::DW_FORM_data4;
791 Die.addValue(DIEValueAllocator, Attribute, Form, DIELocList(Index));
794 void DwarfCompileUnit::applyVariableAttributes(const DbgVariable &Var,
796 StringRef Name = Var.getName();
798 addString(VariableDie, dwarf::DW_AT_name, Name);
799 addSourceLine(VariableDie, Var.getVariable());
800 addType(VariableDie, Var.getType());
801 if (Var.isArtificial())
802 addFlag(VariableDie, dwarf::DW_AT_artificial);
805 /// Add a Dwarf expression attribute data and value.
806 void DwarfCompileUnit::addExpr(DIELoc &Die, dwarf::Form Form,
807 const MCExpr *Expr) {
808 Die.addValue(DIEValueAllocator, (dwarf::Attribute)0, Form, DIEExpr(Expr));
811 void DwarfCompileUnit::applySubprogramAttributesToDefinition(
812 const DISubprogram *SP, DIE &SPDie) {
813 auto *SPDecl = SP->getDeclaration();
814 auto *Context = resolve(SPDecl ? SPDecl->getScope() : SP->getScope());
815 applySubprogramAttributes(SP, SPDie, includeMinimalInlineScopes());
816 addGlobalName(SP->getName(), SPDie, Context);
819 bool DwarfCompileUnit::isDwoUnit() const {
820 return DD->useSplitDwarf() && Skeleton;
823 bool DwarfCompileUnit::includeMinimalInlineScopes() const {
824 return getCUNode()->getEmissionKind() == DIBuilder::LineTablesOnly ||
825 (DD->useSplitDwarf() && !Skeleton);
827 } // end llvm namespace