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, PointerSize == 4
165 ? dwarf::DW_OP_const4u
166 : dwarf::DW_OP_const8u);
167 // 2) containing the (relocated) offset of the TLS variable
168 // within the module's TLS block.
169 addExpr(*Loc, dwarf::DW_FORM_udata,
170 Asm->getObjFileLowering().getDebugThreadLocalSymbol(Sym));
172 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_GNU_const_index);
173 addUInt(*Loc, dwarf::DW_FORM_udata,
174 DD->getAddressPool().getIndex(Sym, /* TLS */ true));
176 // 3) followed by an OP to make the debugger do a TLS lookup.
177 addUInt(*Loc, dwarf::DW_FORM_data1,
178 DD->useGNUTLSOpcode() ? dwarf::DW_OP_GNU_push_tls_address
179 : dwarf::DW_OP_form_tls_address);
182 DD->addArangeLabel(SymbolCU(this, Sym));
183 addOpAddress(*Loc, Sym);
186 addBlock(*VariableDIE, dwarf::DW_AT_location, Loc);
187 addLinkageName(*VariableDIE, GV->getLinkageName());
188 } else if (const ConstantInt *CI =
189 dyn_cast_or_null<ConstantInt>(GV->getVariable())) {
190 addConstantValue(*VariableDIE, CI, GTy);
191 } else if (const ConstantExpr *CE = getMergedGlobalExpr(GV->getVariable())) {
192 addToAccelTable = true;
193 // GV is a merged global.
194 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
195 Value *Ptr = CE->getOperand(0);
196 MCSymbol *Sym = Asm->getSymbol(cast<GlobalValue>(Ptr));
197 DD->addArangeLabel(SymbolCU(this, Sym));
198 addOpAddress(*Loc, Sym);
199 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
200 SmallVector<Value *, 3> Idx(CE->op_begin() + 1, CE->op_end());
201 addUInt(*Loc, dwarf::DW_FORM_udata,
202 Asm->getDataLayout().getIndexedOffset(Ptr->getType(), Idx));
203 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_plus);
204 addBlock(*VariableDIE, dwarf::DW_AT_location, Loc);
207 if (addToAccelTable) {
208 DD->addAccelName(GV->getName(), *VariableDIE);
210 // If the linkage name is different than the name, go ahead and output
211 // that as well into the name table.
212 if (GV->getLinkageName() != "" && GV->getName() != GV->getLinkageName())
213 DD->addAccelName(GV->getLinkageName(), *VariableDIE);
219 void DwarfCompileUnit::addRange(RangeSpan Range) {
220 bool SameAsPrevCU = this == DD->getPrevCU();
222 // If we have no current ranges just add the range and return, otherwise,
223 // check the current section and CU against the previous section and CU we
224 // emitted into and the subprogram was contained within. If these are the
225 // same then extend our current range, otherwise add this as a new range.
226 if (CURanges.empty() || !SameAsPrevCU ||
227 (&CURanges.back().getEnd()->getSection() !=
228 &Range.getEnd()->getSection())) {
229 CURanges.push_back(Range);
233 CURanges.back().setEnd(Range.getEnd());
237 DwarfCompileUnit::addSectionLabel(DIE &Die, dwarf::Attribute Attribute,
238 const MCSymbol *Label, const MCSymbol *Sec) {
239 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
240 return addLabel(Die, Attribute,
241 DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
242 : dwarf::DW_FORM_data4,
244 return addSectionDelta(Die, Attribute, Label, Sec);
247 void DwarfCompileUnit::initStmtList() {
248 // Define start line table label for each Compile Unit.
249 MCSymbol *LineTableStartSym =
250 Asm->OutStreamer->getDwarfLineTableSymbol(getUniqueID());
252 // DW_AT_stmt_list is a offset of line number information for this
253 // compile unit in debug_line section. For split dwarf this is
254 // left in the skeleton CU and so not included.
255 // The line table entries are not always emitted in assembly, so it
256 // is not okay to use line_table_start here.
257 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
259 addSectionLabel(UnitDie, dwarf::DW_AT_stmt_list, LineTableStartSym,
260 TLOF.getDwarfLineSection()->getBeginSymbol());
263 void DwarfCompileUnit::applyStmtList(DIE &D) {
264 D.addValue(DIEValueAllocator, *StmtListValue);
267 void DwarfCompileUnit::attachLowHighPC(DIE &D, const MCSymbol *Begin,
268 const MCSymbol *End) {
269 assert(Begin && "Begin label should not be null!");
270 assert(End && "End label should not be null!");
271 assert(Begin->isDefined() && "Invalid starting label");
272 assert(End->isDefined() && "Invalid end label");
274 addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
275 if (DD->getDwarfVersion() < 4)
276 addLabelAddress(D, dwarf::DW_AT_high_pc, End);
278 addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
281 // Find DIE for the given subprogram and attach appropriate DW_AT_low_pc
282 // and DW_AT_high_pc attributes. If there are global variables in this
283 // scope then create and insert DIEs for these variables.
284 DIE &DwarfCompileUnit::updateSubprogramScopeDIE(const DISubprogram *SP) {
285 DIE *SPDie = getOrCreateSubprogramDIE(SP, includeMinimalInlineScopes());
287 attachLowHighPC(*SPDie, Asm->getFunctionBegin(), Asm->getFunctionEnd());
288 if (!DD->getCurrentFunction()->getTarget().Options.DisableFramePointerElim(
289 *DD->getCurrentFunction()))
290 addFlag(*SPDie, dwarf::DW_AT_APPLE_omit_frame_ptr);
292 // Only include DW_AT_frame_base in full debug info
293 if (!includeMinimalInlineScopes()) {
294 const TargetRegisterInfo *RI = Asm->MF->getSubtarget().getRegisterInfo();
295 MachineLocation Location(RI->getFrameRegister(*Asm->MF));
296 if (RI->isPhysicalRegister(Location.getReg()))
297 addAddress(*SPDie, dwarf::DW_AT_frame_base, Location);
300 // Add name to the name table, we do this here because we're guaranteed
301 // to have concrete versions of our DW_TAG_subprogram nodes.
302 DD->addSubprogramNames(SP, *SPDie);
307 // Construct a DIE for this scope.
308 void DwarfCompileUnit::constructScopeDIE(
309 LexicalScope *Scope, SmallVectorImpl<DIE *> &FinalChildren) {
310 if (!Scope || !Scope->getScopeNode())
313 auto *DS = Scope->getScopeNode();
315 assert((Scope->getInlinedAt() || !isa<DISubprogram>(DS)) &&
316 "Only handle inlined subprograms here, use "
317 "constructSubprogramScopeDIE for non-inlined "
320 SmallVector<DIE *, 8> Children;
322 // We try to create the scope DIE first, then the children DIEs. This will
323 // avoid creating un-used children then removing them later when we find out
324 // the scope DIE is null.
326 if (Scope->getParent() && isa<DISubprogram>(DS)) {
327 ScopeDIE = constructInlinedScopeDIE(Scope);
330 // We create children when the scope DIE is not null.
331 createScopeChildrenDIE(Scope, Children);
333 // Early exit when we know the scope DIE is going to be null.
334 if (DD->isLexicalScopeDIENull(Scope))
337 unsigned ChildScopeCount;
339 // We create children here when we know the scope DIE is not going to be
340 // null and the children will be added to the scope DIE.
341 createScopeChildrenDIE(Scope, Children, &ChildScopeCount);
343 // Skip imported directives in gmlt-like data.
344 if (!includeMinimalInlineScopes()) {
345 // There is no need to emit empty lexical block DIE.
346 for (const auto *IE : ImportedEntities[DS])
348 constructImportedEntityDIE(cast<DIImportedEntity>(IE)));
351 // If there are only other scopes as children, put them directly in the
352 // parent instead, as this scope would serve no purpose.
353 if (Children.size() == ChildScopeCount) {
354 FinalChildren.insert(FinalChildren.end(),
355 std::make_move_iterator(Children.begin()),
356 std::make_move_iterator(Children.end()));
359 ScopeDIE = constructLexicalScopeDIE(Scope);
360 assert(ScopeDIE && "Scope DIE should not be null.");
364 for (auto &I : Children)
365 ScopeDIE->addChild(std::move(I));
367 FinalChildren.push_back(std::move(ScopeDIE));
371 DwarfCompileUnit::addSectionDelta(DIE &Die, dwarf::Attribute Attribute,
372 const MCSymbol *Hi, const MCSymbol *Lo) {
373 return Die.addValue(DIEValueAllocator, Attribute,
374 DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
375 : dwarf::DW_FORM_data4,
376 new (DIEValueAllocator) DIEDelta(Hi, Lo));
379 void DwarfCompileUnit::addScopeRangeList(DIE &ScopeDIE,
380 SmallVector<RangeSpan, 2> Range) {
381 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
383 // Emit offset in .debug_range as a relocatable label. emitDIE will handle
384 // emitting it appropriately.
385 const MCSymbol *RangeSectionSym =
386 TLOF.getDwarfRangesSection()->getBeginSymbol();
388 RangeSpanList List(Asm->createTempSymbol("debug_ranges"), std::move(Range));
390 // Under fission, ranges are specified by constant offsets relative to the
391 // CU's DW_AT_GNU_ranges_base.
393 addSectionDelta(ScopeDIE, dwarf::DW_AT_ranges, List.getSym(),
396 addSectionLabel(ScopeDIE, dwarf::DW_AT_ranges, List.getSym(),
399 // Add the range list to the set of ranges to be emitted.
400 (Skeleton ? Skeleton : this)->CURangeLists.push_back(std::move(List));
403 void DwarfCompileUnit::attachRangesOrLowHighPC(
404 DIE &Die, SmallVector<RangeSpan, 2> Ranges) {
405 if (Ranges.size() == 1) {
406 const auto &single = Ranges.front();
407 attachLowHighPC(Die, single.getStart(), single.getEnd());
409 addScopeRangeList(Die, std::move(Ranges));
412 void DwarfCompileUnit::attachRangesOrLowHighPC(
413 DIE &Die, const SmallVectorImpl<InsnRange> &Ranges) {
414 SmallVector<RangeSpan, 2> List;
415 List.reserve(Ranges.size());
416 for (const InsnRange &R : Ranges)
417 List.push_back(RangeSpan(DD->getLabelBeforeInsn(R.first),
418 DD->getLabelAfterInsn(R.second)));
419 attachRangesOrLowHighPC(Die, std::move(List));
422 // This scope represents inlined body of a function. Construct DIE to
423 // represent this concrete inlined copy of the function.
424 DIE *DwarfCompileUnit::constructInlinedScopeDIE(LexicalScope *Scope) {
425 assert(Scope->getScopeNode());
426 auto *DS = Scope->getScopeNode();
427 auto *InlinedSP = getDISubprogram(DS);
428 // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram
429 // was inlined from another compile unit.
430 DIE *OriginDIE = DU->getAbstractSPDies()[InlinedSP];
431 assert(OriginDIE && "Unable to find original DIE for an inlined subprogram.");
433 auto ScopeDIE = DIE::get(DIEValueAllocator, dwarf::DW_TAG_inlined_subroutine);
434 addDIEEntry(*ScopeDIE, dwarf::DW_AT_abstract_origin, *OriginDIE);
436 attachRangesOrLowHighPC(*ScopeDIE, Scope->getRanges());
438 // Add the call site information to the DIE.
439 const DILocation *IA = Scope->getInlinedAt();
440 addUInt(*ScopeDIE, dwarf::DW_AT_call_file, None,
441 getOrCreateSourceID(IA->getFilename(), IA->getDirectory()));
442 addUInt(*ScopeDIE, dwarf::DW_AT_call_line, None, IA->getLine());
443 if (IA->getDiscriminator())
444 addUInt(*ScopeDIE, dwarf::DW_AT_GNU_discriminator, None,
445 IA->getDiscriminator());
447 // Add name to the name table, we do this here because we're guaranteed
448 // to have concrete versions of our DW_TAG_inlined_subprogram nodes.
449 DD->addSubprogramNames(InlinedSP, *ScopeDIE);
454 // Construct new DW_TAG_lexical_block for this scope and attach
455 // DW_AT_low_pc/DW_AT_high_pc labels.
456 DIE *DwarfCompileUnit::constructLexicalScopeDIE(LexicalScope *Scope) {
457 if (DD->isLexicalScopeDIENull(Scope))
460 auto ScopeDIE = DIE::get(DIEValueAllocator, dwarf::DW_TAG_lexical_block);
461 if (Scope->isAbstractScope())
464 attachRangesOrLowHighPC(*ScopeDIE, Scope->getRanges());
469 /// constructVariableDIE - Construct a DIE for the given DbgVariable.
470 DIE *DwarfCompileUnit::constructVariableDIE(DbgVariable &DV, bool Abstract) {
471 auto D = constructVariableDIEImpl(DV, Abstract);
476 DIE *DwarfCompileUnit::constructVariableDIEImpl(const DbgVariable &DV,
478 // Define variable debug information entry.
479 auto VariableDie = DIE::get(DIEValueAllocator, DV.getTag());
482 applyVariableAttributes(DV, *VariableDie);
486 // Add variable address.
488 unsigned Offset = DV.getDebugLocListIndex();
490 addLocationList(*VariableDie, dwarf::DW_AT_location, Offset);
494 // Check if variable is described by a DBG_VALUE instruction.
495 if (const MachineInstr *DVInsn = DV.getMInsn()) {
496 assert(DVInsn->getNumOperands() == 4);
497 if (DVInsn->getOperand(0).isReg()) {
498 const MachineOperand RegOp = DVInsn->getOperand(0);
499 // If the second operand is an immediate, this is an indirect value.
500 if (DVInsn->getOperand(1).isImm()) {
501 MachineLocation Location(RegOp.getReg(),
502 DVInsn->getOperand(1).getImm());
503 addVariableAddress(DV, *VariableDie, Location);
504 } else if (RegOp.getReg())
505 addVariableAddress(DV, *VariableDie, MachineLocation(RegOp.getReg()));
506 } else if (DVInsn->getOperand(0).isImm())
507 addConstantValue(*VariableDie, DVInsn->getOperand(0), DV.getType());
508 else if (DVInsn->getOperand(0).isFPImm())
509 addConstantFPValue(*VariableDie, DVInsn->getOperand(0));
510 else if (DVInsn->getOperand(0).isCImm())
511 addConstantValue(*VariableDie, DVInsn->getOperand(0).getCImm(),
517 // .. else use frame index.
518 if (DV.getFrameIndex().empty())
521 auto Expr = DV.getExpression().begin();
522 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
523 DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc);
524 for (auto FI : DV.getFrameIndex()) {
525 unsigned FrameReg = 0;
526 const TargetFrameLowering *TFI = Asm->MF->getSubtarget().getFrameLowering();
527 int Offset = TFI->getFrameIndexReference(*Asm->MF, FI, FrameReg);
528 assert(Expr != DV.getExpression().end() && "Wrong number of expressions");
529 DwarfExpr.AddMachineRegIndirect(FrameReg, Offset);
530 DwarfExpr.AddExpression((*Expr)->expr_op_begin(), (*Expr)->expr_op_end());
533 addBlock(*VariableDie, dwarf::DW_AT_location, Loc);
538 DIE *DwarfCompileUnit::constructVariableDIE(DbgVariable &DV,
539 const LexicalScope &Scope,
540 DIE *&ObjectPointer) {
541 auto Var = constructVariableDIE(DV, Scope.isAbstractScope());
542 if (DV.isObjectPointer())
547 DIE *DwarfCompileUnit::createScopeChildrenDIE(LexicalScope *Scope,
548 SmallVectorImpl<DIE *> &Children,
549 unsigned *ChildScopeCount) {
550 DIE *ObjectPointer = nullptr;
552 for (DbgVariable *DV : DU->getScopeVariables().lookup(Scope))
553 Children.push_back(constructVariableDIE(*DV, *Scope, ObjectPointer));
555 unsigned ChildCountWithoutScopes = Children.size();
557 for (LexicalScope *LS : Scope->getChildren())
558 constructScopeDIE(LS, Children);
561 *ChildScopeCount = Children.size() - ChildCountWithoutScopes;
563 return ObjectPointer;
566 void DwarfCompileUnit::constructSubprogramScopeDIE(LexicalScope *Scope) {
567 assert(Scope && Scope->getScopeNode());
568 assert(!Scope->getInlinedAt());
569 assert(!Scope->isAbstractScope());
570 auto *Sub = cast<DISubprogram>(Scope->getScopeNode());
572 DD->getProcessedSPNodes().insert(Sub);
574 DIE &ScopeDIE = updateSubprogramScopeDIE(Sub);
576 // If this is a variadic function, add an unspecified parameter.
577 DITypeRefArray FnArgs = Sub->getType()->getTypeArray();
579 // Collect lexical scope children first.
580 // ObjectPointer might be a local (non-argument) local variable if it's a
581 // block's synthetic this pointer.
582 if (DIE *ObjectPointer = createAndAddScopeChildren(Scope, ScopeDIE))
583 addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer);
585 // If we have a single element of null, it is a function that returns void.
586 // If we have more than one elements and the last one is null, it is a
587 // variadic function.
588 if (FnArgs.size() > 1 && !FnArgs[FnArgs.size() - 1] &&
589 !includeMinimalInlineScopes())
591 DIE::get(DIEValueAllocator, dwarf::DW_TAG_unspecified_parameters));
594 DIE *DwarfCompileUnit::createAndAddScopeChildren(LexicalScope *Scope,
596 // We create children when the scope DIE is not null.
597 SmallVector<DIE *, 8> Children;
598 DIE *ObjectPointer = createScopeChildrenDIE(Scope, Children);
601 for (auto &I : Children)
602 ScopeDIE.addChild(std::move(I));
604 return ObjectPointer;
607 void DwarfCompileUnit::constructAbstractSubprogramScopeDIE(
608 LexicalScope *Scope) {
609 DIE *&AbsDef = DU->getAbstractSPDies()[Scope->getScopeNode()];
613 auto *SP = cast<DISubprogram>(Scope->getScopeNode());
617 if (includeMinimalInlineScopes())
618 ContextDIE = &getUnitDie();
619 // Some of this is duplicated from DwarfUnit::getOrCreateSubprogramDIE, with
620 // the important distinction that the debug node is not associated with the
621 // DIE (since the debug node will be associated with the concrete DIE, if
622 // any). It could be refactored to some common utility function.
623 else if (auto *SPDecl = SP->getDeclaration()) {
624 ContextDIE = &getUnitDie();
625 getOrCreateSubprogramDIE(SPDecl);
627 ContextDIE = getOrCreateContextDIE(resolve(SP->getScope()));
629 // Passing null as the associated node because the abstract definition
630 // shouldn't be found by lookup.
631 AbsDef = &createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, nullptr);
632 applySubprogramAttributesToDefinition(SP, *AbsDef);
634 if (!includeMinimalInlineScopes())
635 addUInt(*AbsDef, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
636 if (DIE *ObjectPointer = createAndAddScopeChildren(Scope, *AbsDef))
637 addDIEEntry(*AbsDef, dwarf::DW_AT_object_pointer, *ObjectPointer);
640 DIE *DwarfCompileUnit::constructImportedEntityDIE(
641 const DIImportedEntity *Module) {
642 DIE *IMDie = DIE::get(DIEValueAllocator, (dwarf::Tag)Module->getTag());
643 insertDIE(Module, IMDie);
645 auto *Entity = resolve(Module->getEntity());
646 if (auto *NS = dyn_cast<DINamespace>(Entity))
647 EntityDie = getOrCreateNameSpace(NS);
648 else if (auto *M = dyn_cast<DIModule>(Entity))
649 EntityDie = getOrCreateModule(M);
650 else if (auto *SP = dyn_cast<DISubprogram>(Entity))
651 EntityDie = getOrCreateSubprogramDIE(SP);
652 else if (auto *T = dyn_cast<DIType>(Entity))
653 EntityDie = getOrCreateTypeDIE(T);
654 else if (auto *GV = dyn_cast<DIGlobalVariable>(Entity))
655 EntityDie = getOrCreateGlobalVariableDIE(GV);
657 EntityDie = getDIE(Entity);
659 addSourceLine(*IMDie, Module->getLine(), Module->getScope()->getFilename(),
660 Module->getScope()->getDirectory());
661 addDIEEntry(*IMDie, dwarf::DW_AT_import, *EntityDie);
662 StringRef Name = Module->getName();
664 addString(*IMDie, dwarf::DW_AT_name, Name);
669 void DwarfCompileUnit::finishSubprogramDefinition(const DISubprogram *SP) {
671 if (DIE *AbsSPDIE = DU->getAbstractSPDies().lookup(SP)) {
673 // If this subprogram has an abstract definition, reference that
674 addDIEEntry(*D, dwarf::DW_AT_abstract_origin, *AbsSPDIE);
676 if (!D && !includeMinimalInlineScopes())
677 // Lazily construct the subprogram if we didn't see either concrete or
678 // inlined versions during codegen. (except in -gmlt ^ where we want
679 // to omit these entirely)
680 D = getOrCreateSubprogramDIE(SP);
682 // And attach the attributes
683 applySubprogramAttributesToDefinition(SP, *D);
686 void DwarfCompileUnit::collectDeadVariables(const DISubprogram *SP) {
687 assert(SP && "CU's subprogram list contains a non-subprogram");
688 assert(SP->isDefinition() &&
689 "CU's subprogram list contains a subprogram declaration");
690 auto Variables = SP->getVariables();
691 if (Variables.size() == 0)
694 DIE *SPDIE = DU->getAbstractSPDies().lookup(SP);
698 for (const DILocalVariable *DV : Variables) {
699 DbgVariable NewVar(DV, /* IA */ nullptr, DD);
700 auto VariableDie = constructVariableDIE(NewVar);
701 applyVariableAttributes(NewVar, *VariableDie);
702 SPDIE->addChild(std::move(VariableDie));
706 void DwarfCompileUnit::emitHeader(bool UseOffsets) {
707 // Don't bother labeling the .dwo unit, as its offset isn't used.
709 LabelBegin = Asm->createTempSymbol("cu_begin");
710 Asm->OutStreamer->EmitLabel(LabelBegin);
713 DwarfUnit::emitHeader(UseOffsets);
716 /// addGlobalName - Add a new global name to the compile unit.
717 void DwarfCompileUnit::addGlobalName(StringRef Name, DIE &Die,
718 const DIScope *Context) {
719 if (includeMinimalInlineScopes())
721 std::string FullName = getParentContextString(Context) + Name.str();
722 GlobalNames[FullName] = &Die;
725 /// Add a new global type to the unit.
726 void DwarfCompileUnit::addGlobalType(const DIType *Ty, const DIE &Die,
727 const DIScope *Context) {
728 if (includeMinimalInlineScopes())
730 std::string FullName = getParentContextString(Context) + Ty->getName().str();
731 GlobalTypes[FullName] = &Die;
734 /// addVariableAddress - Add DW_AT_location attribute for a
735 /// DbgVariable based on provided MachineLocation.
736 void DwarfCompileUnit::addVariableAddress(const DbgVariable &DV, DIE &Die,
737 MachineLocation Location) {
738 if (DV.hasComplexAddress())
739 addComplexAddress(DV, Die, dwarf::DW_AT_location, Location);
740 else if (DV.isBlockByrefVariable())
741 addBlockByrefAddress(DV, Die, dwarf::DW_AT_location, Location);
743 addAddress(Die, dwarf::DW_AT_location, Location);
746 /// Add an address attribute to a die based on the location provided.
747 void DwarfCompileUnit::addAddress(DIE &Die, dwarf::Attribute Attribute,
748 const MachineLocation &Location) {
749 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
752 if (Location.isReg())
753 validReg = addRegisterOpPiece(*Loc, Location.getReg());
755 validReg = addRegisterOffset(*Loc, Location.getReg(), Location.getOffset());
760 // Now attach the location information to the DIE.
761 addBlock(Die, Attribute, Loc);
764 /// Start with the address based on the location provided, and generate the
765 /// DWARF information necessary to find the actual variable given the extra
766 /// address information encoded in the DbgVariable, starting from the starting
767 /// location. Add the DWARF information to the die.
768 void DwarfCompileUnit::addComplexAddress(const DbgVariable &DV, DIE &Die,
769 dwarf::Attribute Attribute,
770 const MachineLocation &Location) {
771 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
772 DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc);
773 assert(DV.getExpression().size() == 1);
774 const DIExpression *Expr = DV.getExpression().back();
776 if (Location.getOffset()) {
777 ValidReg = DwarfExpr.AddMachineRegIndirect(Location.getReg(),
778 Location.getOffset());
780 DwarfExpr.AddExpression(Expr->expr_op_begin(), Expr->expr_op_end());
782 ValidReg = DwarfExpr.AddMachineRegExpression(Expr, Location.getReg());
784 // Now attach the location information to the DIE.
786 addBlock(Die, Attribute, Loc);
789 /// Add a Dwarf loclistptr attribute data and value.
790 void DwarfCompileUnit::addLocationList(DIE &Die, dwarf::Attribute Attribute,
792 dwarf::Form Form = DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
793 : dwarf::DW_FORM_data4;
794 Die.addValue(DIEValueAllocator, Attribute, Form, DIELocList(Index));
797 void DwarfCompileUnit::applyVariableAttributes(const DbgVariable &Var,
799 StringRef Name = Var.getName();
801 addString(VariableDie, dwarf::DW_AT_name, Name);
802 addSourceLine(VariableDie, Var.getVariable());
803 addType(VariableDie, Var.getType());
804 if (Var.isArtificial())
805 addFlag(VariableDie, dwarf::DW_AT_artificial);
808 /// Add a Dwarf expression attribute data and value.
809 void DwarfCompileUnit::addExpr(DIELoc &Die, dwarf::Form Form,
810 const MCExpr *Expr) {
811 Die.addValue(DIEValueAllocator, (dwarf::Attribute)0, Form, DIEExpr(Expr));
814 void DwarfCompileUnit::applySubprogramAttributesToDefinition(
815 const DISubprogram *SP, DIE &SPDie) {
816 auto *SPDecl = SP->getDeclaration();
817 auto *Context = resolve(SPDecl ? SPDecl->getScope() : SP->getScope());
818 applySubprogramAttributes(SP, SPDie, includeMinimalInlineScopes());
819 addGlobalName(SP->getName(), SPDie, Context);
822 bool DwarfCompileUnit::isDwoUnit() const {
823 return DD->useSplitDwarf() && Skeleton;
826 bool DwarfCompileUnit::includeMinimalInlineScopes() const {
827 return getCUNode()->getEmissionKind() == DIBuilder::LineTablesOnly ||
828 (DD->useSplitDwarf() && !Skeleton);
830 } // end llvm namespace