1 #include "DwarfCompileUnit.h"
2 #include "DwarfExpression.h"
3 #include "llvm/CodeGen/MachineFunction.h"
4 #include "llvm/IR/DataLayout.h"
5 #include "llvm/IR/GlobalValue.h"
6 #include "llvm/IR/GlobalVariable.h"
7 #include "llvm/IR/Instruction.h"
8 #include "llvm/MC/MCAsmInfo.h"
9 #include "llvm/MC/MCStreamer.h"
10 #include "llvm/Target/TargetFrameLowering.h"
11 #include "llvm/Target/TargetLoweringObjectFile.h"
12 #include "llvm/Target/TargetMachine.h"
13 #include "llvm/Target/TargetRegisterInfo.h"
14 #include "llvm/Target/TargetSubtargetInfo.h"
18 DwarfCompileUnit::DwarfCompileUnit(unsigned UID, DICompileUnit Node,
19 AsmPrinter *A, DwarfDebug *DW,
21 : DwarfUnit(UID, dwarf::DW_TAG_compile_unit, Node, A, DW, DWU),
22 Skeleton(nullptr), BaseAddress(nullptr) {
23 insertDIE(Node, &getUnitDie());
26 /// addLabelAddress - Add a dwarf label attribute data and value using
27 /// DW_FORM_addr or DW_FORM_GNU_addr_index.
29 void DwarfCompileUnit::addLabelAddress(DIE &Die, dwarf::Attribute Attribute,
30 const MCSymbol *Label) {
32 // Don't use the address pool in non-fission or in the skeleton unit itself.
33 // FIXME: Once GDB supports this, it's probably worthwhile using the address
34 // pool from the skeleton - maybe even in non-fission (possibly fewer
35 // relocations by sharing them in the pool, but we have other ideas about how
36 // to reduce the number of relocations as well/instead).
37 if (!DD->useSplitDwarf() || !Skeleton)
38 return addLocalLabelAddress(Die, Attribute, Label);
41 DD->addArangeLabel(SymbolCU(this, Label));
43 unsigned idx = DD->getAddressPool().getIndex(Label);
44 DIEValue *Value = new (DIEValueAllocator) DIEInteger(idx);
45 Die.addValue(Attribute, dwarf::DW_FORM_GNU_addr_index, Value);
48 void DwarfCompileUnit::addLocalLabelAddress(DIE &Die,
49 dwarf::Attribute Attribute,
50 const MCSymbol *Label) {
52 DD->addArangeLabel(SymbolCU(this, Label));
54 Die.addValue(Attribute, dwarf::DW_FORM_addr,
55 Label ? (DIEValue *)new (DIEValueAllocator) DIELabel(Label)
56 : new (DIEValueAllocator) DIEInteger(0));
59 unsigned DwarfCompileUnit::getOrCreateSourceID(StringRef FileName,
61 // If we print assembly, we can't separate .file entries according to
62 // compile units. Thus all files will belong to the default compile unit.
64 // FIXME: add a better feature test than hasRawTextSupport. Even better,
65 // extend .file to support this.
66 return Asm->OutStreamer.EmitDwarfFileDirective(
68 Asm->OutStreamer.hasRawTextSupport() ? 0 : getUniqueID());
71 // Return const expression if value is a GEP to access merged global
73 // i8* getelementptr ({ i8, i8, i8, i8 }* @_MergedGlobals, i32 0, i32 0)
74 static const ConstantExpr *getMergedGlobalExpr(const Value *V) {
75 const ConstantExpr *CE = dyn_cast_or_null<ConstantExpr>(V);
76 if (!CE || CE->getNumOperands() != 3 ||
77 CE->getOpcode() != Instruction::GetElementPtr)
80 // First operand points to a global struct.
81 Value *Ptr = CE->getOperand(0);
82 if (!isa<GlobalValue>(Ptr) ||
83 !isa<StructType>(cast<PointerType>(Ptr->getType())->getElementType()))
86 // Second operand is zero.
87 const ConstantInt *CI = dyn_cast_or_null<ConstantInt>(CE->getOperand(1));
88 if (!CI || !CI->isZero())
91 // Third operand is offset.
92 if (!isa<ConstantInt>(CE->getOperand(2)))
98 /// getOrCreateGlobalVariableDIE - get or create global variable DIE.
99 DIE *DwarfCompileUnit::getOrCreateGlobalVariableDIE(DIGlobalVariable GV) {
100 // Check for pre-existence.
101 if (DIE *Die = getDIE(GV))
104 assert(GV.isGlobalVariable());
106 DIScope GVContext = GV.getContext();
107 DIType GTy = DD->resolve(GV.getType());
109 // Construct the context before querying for the existence of the DIE in
110 // case such construction creates the DIE.
111 DIE *ContextDIE = getOrCreateContextDIE(GVContext);
114 DIE *VariableDIE = &createAndAddDIE(GV.getTag(), *ContextDIE, GV);
117 if (DIDerivedType SDMDecl = GV.getStaticDataMemberDeclaration()) {
118 DeclContext = resolve(SDMDecl.getContext());
119 assert(SDMDecl.isStaticMember() && "Expected static member decl");
120 assert(GV.isDefinition());
121 // We need the declaration DIE that is in the static member's class.
122 DIE *VariableSpecDIE = getOrCreateStaticMemberDIE(SDMDecl);
123 addDIEEntry(*VariableDIE, dwarf::DW_AT_specification, *VariableSpecDIE);
125 DeclContext = GV.getContext();
126 // Add name and type.
127 addString(*VariableDIE, dwarf::DW_AT_name, GV.getDisplayName());
128 addType(*VariableDIE, GTy);
131 if (!GV.isLocalToUnit())
132 addFlag(*VariableDIE, dwarf::DW_AT_external);
134 // Add line number info.
135 addSourceLine(*VariableDIE, GV);
138 if (!GV.isDefinition())
139 addFlag(*VariableDIE, dwarf::DW_AT_declaration);
142 bool addToAccelTable = false;
143 bool isGlobalVariable = GV.getGlobal() != nullptr;
144 if (isGlobalVariable) {
145 addToAccelTable = true;
146 DIELoc *Loc = new (DIEValueAllocator) DIELoc();
147 const MCSymbol *Sym = Asm->getSymbol(GV.getGlobal());
148 if (GV.getGlobal()->isThreadLocal()) {
149 // FIXME: Make this work with -gsplit-dwarf.
150 unsigned PointerSize = Asm->getDataLayout().getPointerSize();
151 assert((PointerSize == 4 || PointerSize == 8) &&
152 "Add support for other sizes if necessary");
153 // Based on GCC's support for TLS:
154 if (!DD->useSplitDwarf()) {
155 // 1) Start with a constNu of the appropriate pointer size
156 addUInt(*Loc, dwarf::DW_FORM_data1,
157 PointerSize == 4 ? dwarf::DW_OP_const4u : dwarf::DW_OP_const8u);
158 // 2) containing the (relocated) offset of the TLS variable
159 // within the module's TLS block.
160 addExpr(*Loc, dwarf::DW_FORM_udata,
161 Asm->getObjFileLowering().getDebugThreadLocalSymbol(Sym));
163 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_GNU_const_index);
164 addUInt(*Loc, dwarf::DW_FORM_udata,
165 DD->getAddressPool().getIndex(Sym, /* TLS */ true));
167 // 3) followed by an OP to make the debugger do a TLS lookup.
168 addUInt(*Loc, dwarf::DW_FORM_data1,
169 DD->useGNUTLSOpcode() ? dwarf::DW_OP_GNU_push_tls_address
170 : dwarf::DW_OP_form_tls_address);
172 DD->addArangeLabel(SymbolCU(this, Sym));
173 addOpAddress(*Loc, Sym);
176 addBlock(*VariableDIE, dwarf::DW_AT_location, Loc);
177 // Add the linkage name.
178 StringRef LinkageName = GV.getLinkageName();
179 if (!LinkageName.empty())
180 // From DWARF4: DIEs to which DW_AT_linkage_name may apply include:
181 // TAG_common_block, TAG_constant, TAG_entry_point, TAG_subprogram and
183 addString(*VariableDIE,
184 DD->getDwarfVersion() >= 4 ? dwarf::DW_AT_linkage_name
185 : dwarf::DW_AT_MIPS_linkage_name,
186 GlobalValue::getRealLinkageName(LinkageName));
187 } else if (const ConstantInt *CI =
188 dyn_cast_or_null<ConstantInt>(GV.getConstant())) {
189 addConstantValue(*VariableDIE, CI, GTy);
190 } else if (const ConstantExpr *CE = getMergedGlobalExpr(GV.getConstant())) {
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);
215 addGlobalName(GV.getName(), *VariableDIE, DeclContext);
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());
236 void DwarfCompileUnit::addSectionLabel(DIE &Die, dwarf::Attribute Attribute,
237 const MCSymbol *Label,
238 const MCSymbol *Sec) {
239 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
240 addLabel(Die, Attribute,
241 DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
242 : dwarf::DW_FORM_data4,
245 addSectionDelta(Die, Attribute, Label, Sec);
248 void DwarfCompileUnit::initStmtList() {
249 // Define start line table label for each Compile Unit.
250 MCSymbol *LineTableStartSym =
251 Asm->OutStreamer.getDwarfLineTableSymbol(getUniqueID());
253 stmtListIndex = UnitDie.getValues().size();
255 // DW_AT_stmt_list is a offset of line number information for this
256 // compile unit in debug_line section. For split dwarf this is
257 // left in the skeleton CU and so not included.
258 // The line table entries are not always emitted in assembly, so it
259 // is not okay to use line_table_start here.
260 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
261 addSectionLabel(UnitDie, dwarf::DW_AT_stmt_list, LineTableStartSym,
262 TLOF.getDwarfLineSection()->getBeginSymbol());
265 void DwarfCompileUnit::applyStmtList(DIE &D) {
266 D.addValue(dwarf::DW_AT_stmt_list,
267 UnitDie.getAbbrev().getData()[stmtListIndex].getForm(),
268 UnitDie.getValues()[stmtListIndex]);
271 void DwarfCompileUnit::attachLowHighPC(DIE &D, const MCSymbol *Begin,
272 const MCSymbol *End) {
273 assert(Begin && "Begin label should not be null!");
274 assert(End && "End label should not be null!");
275 assert(Begin->isDefined() && "Invalid starting label");
276 assert(End->isDefined() && "Invalid end label");
278 addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
279 if (DD->getDwarfVersion() < 4)
280 addLabelAddress(D, dwarf::DW_AT_high_pc, End);
282 addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
285 // Find DIE for the given subprogram and attach appropriate DW_AT_low_pc
286 // and DW_AT_high_pc attributes. If there are global variables in this
287 // scope then create and insert DIEs for these variables.
288 DIE &DwarfCompileUnit::updateSubprogramScopeDIE(DISubprogram SP) {
289 DIE *SPDie = getOrCreateSubprogramDIE(SP, includeMinimalInlineScopes());
291 attachLowHighPC(*SPDie, Asm->getFunctionBegin(), Asm->getFunctionEnd());
292 if (!DD->getCurrentFunction()->getTarget().Options.DisableFramePointerElim(
293 *DD->getCurrentFunction()))
294 addFlag(*SPDie, dwarf::DW_AT_APPLE_omit_frame_ptr);
296 // Only include DW_AT_frame_base in full debug info
297 if (!includeMinimalInlineScopes()) {
298 const TargetRegisterInfo *RI = Asm->MF->getSubtarget().getRegisterInfo();
299 MachineLocation Location(RI->getFrameRegister(*Asm->MF));
300 if (RI->isPhysicalRegister(Location.getReg()))
301 addAddress(*SPDie, dwarf::DW_AT_frame_base, Location);
304 // Add name to the name table, we do this here because we're guaranteed
305 // to have concrete versions of our DW_TAG_subprogram nodes.
306 DD->addSubprogramNames(SP, *SPDie);
311 // Construct a DIE for this scope.
312 void DwarfCompileUnit::constructScopeDIE(
313 LexicalScope *Scope, SmallVectorImpl<std::unique_ptr<DIE>> &FinalChildren) {
314 if (!Scope || !Scope->getScopeNode())
317 DIScope DS(Scope->getScopeNode());
319 assert((Scope->getInlinedAt() || !DS.isSubprogram()) &&
320 "Only handle inlined subprograms here, use "
321 "constructSubprogramScopeDIE for non-inlined "
324 SmallVector<std::unique_ptr<DIE>, 8> Children;
326 // We try to create the scope DIE first, then the children DIEs. This will
327 // avoid creating un-used children then removing them later when we find out
328 // the scope DIE is null.
329 std::unique_ptr<DIE> ScopeDIE;
330 if (Scope->getParent() && DS.isSubprogram()) {
331 ScopeDIE = constructInlinedScopeDIE(Scope);
334 // We create children when the scope DIE is not null.
335 createScopeChildrenDIE(Scope, Children);
337 // Early exit when we know the scope DIE is going to be null.
338 if (DD->isLexicalScopeDIENull(Scope))
341 unsigned ChildScopeCount;
343 // We create children here when we know the scope DIE is not going to be
344 // null and the children will be added to the scope DIE.
345 createScopeChildrenDIE(Scope, Children, &ChildScopeCount);
347 // Skip imported directives in gmlt-like data.
348 if (!includeMinimalInlineScopes()) {
349 // There is no need to emit empty lexical block DIE.
350 for (const auto &E : DD->findImportedEntitiesForScope(DS))
352 constructImportedEntityDIE(DIImportedEntity(E.second)));
355 // If there are only other scopes as children, put them directly in the
356 // parent instead, as this scope would serve no purpose.
357 if (Children.size() == ChildScopeCount) {
358 FinalChildren.insert(FinalChildren.end(),
359 std::make_move_iterator(Children.begin()),
360 std::make_move_iterator(Children.end()));
363 ScopeDIE = constructLexicalScopeDIE(Scope);
364 assert(ScopeDIE && "Scope DIE should not be null.");
368 for (auto &I : Children)
369 ScopeDIE->addChild(std::move(I));
371 FinalChildren.push_back(std::move(ScopeDIE));
374 void DwarfCompileUnit::addSectionDelta(DIE &Die, dwarf::Attribute Attribute,
375 const MCSymbol *Hi, const MCSymbol *Lo) {
376 DIEValue *Value = new (DIEValueAllocator) DIEDelta(Hi, Lo);
377 Die.addValue(Attribute, DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
378 : dwarf::DW_FORM_data4,
382 void DwarfCompileUnit::addScopeRangeList(DIE &ScopeDIE,
383 SmallVector<RangeSpan, 2> Range) {
384 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
386 // Emit offset in .debug_range as a relocatable label. emitDIE will handle
387 // emitting it appropriately.
388 const MCSymbol *RangeSectionSym =
389 TLOF.getDwarfRangesSection()->getBeginSymbol();
392 Asm->GetTempSymbol("debug_ranges", DD->getNextRangeNumber()),
395 // Under fission, ranges are specified by constant offsets relative to the
396 // CU's DW_AT_GNU_ranges_base.
398 addSectionDelta(ScopeDIE, dwarf::DW_AT_ranges, List.getSym(),
401 addSectionLabel(ScopeDIE, dwarf::DW_AT_ranges, List.getSym(),
404 // Add the range list to the set of ranges to be emitted.
405 (Skeleton ? Skeleton : this)->CURangeLists.push_back(std::move(List));
408 void DwarfCompileUnit::attachRangesOrLowHighPC(
409 DIE &Die, SmallVector<RangeSpan, 2> Ranges) {
410 if (Ranges.size() == 1) {
411 const auto &single = Ranges.front();
412 attachLowHighPC(Die, single.getStart(), single.getEnd());
414 addScopeRangeList(Die, std::move(Ranges));
417 void DwarfCompileUnit::attachRangesOrLowHighPC(
418 DIE &Die, const SmallVectorImpl<InsnRange> &Ranges) {
419 SmallVector<RangeSpan, 2> List;
420 List.reserve(Ranges.size());
421 for (const InsnRange &R : Ranges)
422 List.push_back(RangeSpan(DD->getLabelBeforeInsn(R.first),
423 DD->getLabelAfterInsn(R.second)));
424 attachRangesOrLowHighPC(Die, std::move(List));
427 // This scope represents inlined body of a function. Construct DIE to
428 // represent this concrete inlined copy of the function.
430 DwarfCompileUnit::constructInlinedScopeDIE(LexicalScope *Scope) {
431 assert(Scope->getScopeNode());
432 DIScope DS(Scope->getScopeNode());
433 DISubprogram InlinedSP = getDISubprogram(DS);
434 // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram
435 // was inlined from another compile unit.
436 DIE *OriginDIE = DU->getAbstractSPDies()[InlinedSP];
437 assert(OriginDIE && "Unable to find original DIE for an inlined subprogram.");
439 auto ScopeDIE = make_unique<DIE>(dwarf::DW_TAG_inlined_subroutine);
440 addDIEEntry(*ScopeDIE, dwarf::DW_AT_abstract_origin, *OriginDIE);
442 attachRangesOrLowHighPC(*ScopeDIE, Scope->getRanges());
444 // Add the call site information to the DIE.
445 DILocation DL(Scope->getInlinedAt());
446 addUInt(*ScopeDIE, dwarf::DW_AT_call_file, None,
447 getOrCreateSourceID(DL.getFilename(), DL.getDirectory()));
448 addUInt(*ScopeDIE, dwarf::DW_AT_call_line, None, DL.getLineNumber());
450 // Add name to the name table, we do this here because we're guaranteed
451 // to have concrete versions of our DW_TAG_inlined_subprogram nodes.
452 DD->addSubprogramNames(InlinedSP, *ScopeDIE);
457 // Construct new DW_TAG_lexical_block for this scope and attach
458 // DW_AT_low_pc/DW_AT_high_pc labels.
460 DwarfCompileUnit::constructLexicalScopeDIE(LexicalScope *Scope) {
461 if (DD->isLexicalScopeDIENull(Scope))
464 auto ScopeDIE = make_unique<DIE>(dwarf::DW_TAG_lexical_block);
465 if (Scope->isAbstractScope())
468 attachRangesOrLowHighPC(*ScopeDIE, Scope->getRanges());
473 /// constructVariableDIE - Construct a DIE for the given DbgVariable.
474 std::unique_ptr<DIE> DwarfCompileUnit::constructVariableDIE(DbgVariable &DV,
476 auto D = constructVariableDIEImpl(DV, Abstract);
482 DwarfCompileUnit::constructVariableDIEImpl(const DbgVariable &DV,
484 // Define variable debug information entry.
485 auto VariableDie = make_unique<DIE>(DV.getTag());
488 applyVariableAttributes(DV, *VariableDie);
492 // Add variable address.
494 unsigned Offset = DV.getDotDebugLocOffset();
496 addLocationList(*VariableDie, dwarf::DW_AT_location, Offset);
500 // Check if variable is described by a DBG_VALUE instruction.
501 if (const MachineInstr *DVInsn = DV.getMInsn()) {
502 assert(DVInsn->getNumOperands() == 4);
503 if (DVInsn->getOperand(0).isReg()) {
504 const MachineOperand RegOp = DVInsn->getOperand(0);
505 // If the second operand is an immediate, this is an indirect value.
506 if (DVInsn->getOperand(1).isImm()) {
507 MachineLocation Location(RegOp.getReg(),
508 DVInsn->getOperand(1).getImm());
509 addVariableAddress(DV, *VariableDie, Location);
510 } else if (RegOp.getReg())
511 addVariableAddress(DV, *VariableDie, MachineLocation(RegOp.getReg()));
512 } else if (DVInsn->getOperand(0).isImm())
513 addConstantValue(*VariableDie, DVInsn->getOperand(0), DV.getType());
514 else if (DVInsn->getOperand(0).isFPImm())
515 addConstantFPValue(*VariableDie, DVInsn->getOperand(0));
516 else if (DVInsn->getOperand(0).isCImm())
517 addConstantValue(*VariableDie, DVInsn->getOperand(0).getCImm(),
523 // .. else use frame index.
524 if (DV.getFrameIndex().back() == ~0)
527 auto Expr = DV.getExpression().begin();
528 DIELoc *Loc = new (DIEValueAllocator) DIELoc();
529 DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc);
530 for (auto FI : DV.getFrameIndex()) {
531 unsigned FrameReg = 0;
532 const TargetFrameLowering *TFI = Asm->MF->getSubtarget().getFrameLowering();
533 int Offset = TFI->getFrameIndexReference(*Asm->MF, FI, FrameReg);
534 assert(Expr != DV.getExpression().end() &&
535 "Wrong number of expressions");
536 DwarfExpr.AddMachineRegIndirect(FrameReg, Offset);
537 DwarfExpr.AddExpression(Expr->begin(), Expr->end());
540 addBlock(*VariableDie, dwarf::DW_AT_location, Loc);
545 std::unique_ptr<DIE> DwarfCompileUnit::constructVariableDIE(
546 DbgVariable &DV, const LexicalScope &Scope, DIE *&ObjectPointer) {
547 auto Var = constructVariableDIE(DV, Scope.isAbstractScope());
548 if (DV.isObjectPointer())
549 ObjectPointer = Var.get();
553 DIE *DwarfCompileUnit::createScopeChildrenDIE(
554 LexicalScope *Scope, SmallVectorImpl<std::unique_ptr<DIE>> &Children,
555 unsigned *ChildScopeCount) {
556 DIE *ObjectPointer = nullptr;
558 for (DbgVariable *DV : DU->getScopeVariables().lookup(Scope))
559 Children.push_back(constructVariableDIE(*DV, *Scope, ObjectPointer));
561 unsigned ChildCountWithoutScopes = Children.size();
563 for (LexicalScope *LS : Scope->getChildren())
564 constructScopeDIE(LS, Children);
567 *ChildScopeCount = Children.size() - ChildCountWithoutScopes;
569 return ObjectPointer;
572 void DwarfCompileUnit::constructSubprogramScopeDIE(LexicalScope *Scope) {
573 assert(Scope && Scope->getScopeNode());
574 assert(!Scope->getInlinedAt());
575 assert(!Scope->isAbstractScope());
576 DISubprogram Sub(Scope->getScopeNode());
578 assert(Sub.isSubprogram());
580 DD->getProcessedSPNodes().insert(Sub);
582 DIE &ScopeDIE = updateSubprogramScopeDIE(Sub);
584 // If this is a variadic function, add an unspecified parameter.
585 DITypeArray FnArgs = Sub.getType().getTypeArray();
587 // Collect lexical scope children first.
588 // ObjectPointer might be a local (non-argument) local variable if it's a
589 // block's synthetic this pointer.
590 if (DIE *ObjectPointer = createAndAddScopeChildren(Scope, ScopeDIE))
591 addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer);
593 // If we have a single element of null, it is a function that returns void.
594 // If we have more than one elements and the last one is null, it is a
595 // variadic function.
596 if (FnArgs.getNumElements() > 1 &&
597 !FnArgs.getElement(FnArgs.getNumElements() - 1) &&
598 !includeMinimalInlineScopes())
599 ScopeDIE.addChild(make_unique<DIE>(dwarf::DW_TAG_unspecified_parameters));
602 DIE *DwarfCompileUnit::createAndAddScopeChildren(LexicalScope *Scope,
604 // We create children when the scope DIE is not null.
605 SmallVector<std::unique_ptr<DIE>, 8> Children;
606 DIE *ObjectPointer = createScopeChildrenDIE(Scope, Children);
609 for (auto &I : Children)
610 ScopeDIE.addChild(std::move(I));
612 return ObjectPointer;
616 DwarfCompileUnit::constructAbstractSubprogramScopeDIE(LexicalScope *Scope) {
617 DIE *&AbsDef = DU->getAbstractSPDies()[Scope->getScopeNode()];
621 DISubprogram SP(Scope->getScopeNode());
625 if (includeMinimalInlineScopes())
626 ContextDIE = &getUnitDie();
627 // Some of this is duplicated from DwarfUnit::getOrCreateSubprogramDIE, with
628 // the important distinction that the DIDescriptor is not associated with the
629 // DIE (since the DIDescriptor will be associated with the concrete DIE, if
630 // any). It could be refactored to some common utility function.
631 else if (DISubprogram SPDecl = SP.getFunctionDeclaration()) {
632 ContextDIE = &getUnitDie();
633 getOrCreateSubprogramDIE(SPDecl);
635 ContextDIE = getOrCreateContextDIE(resolve(SP.getContext()));
637 // Passing null as the associated DIDescriptor because the abstract definition
638 // shouldn't be found by lookup.
640 &createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, DIDescriptor());
641 applySubprogramAttributesToDefinition(SP, *AbsDef);
643 if (!includeMinimalInlineScopes())
644 addUInt(*AbsDef, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
645 if (DIE *ObjectPointer = createAndAddScopeChildren(Scope, *AbsDef))
646 addDIEEntry(*AbsDef, dwarf::DW_AT_object_pointer, *ObjectPointer);
650 DwarfCompileUnit::constructImportedEntityDIE(const DIImportedEntity &Module) {
651 assert(Module.Verify() &&
652 "Use one of the MDNode * overloads to handle invalid metadata");
653 std::unique_ptr<DIE> IMDie = make_unique<DIE>((dwarf::Tag)Module.getTag());
654 insertDIE(Module, IMDie.get());
656 DIDescriptor Entity = resolve(Module.getEntity());
657 if (Entity.isNameSpace())
658 EntityDie = getOrCreateNameSpace(DINameSpace(Entity));
659 else if (Entity.isSubprogram())
660 EntityDie = getOrCreateSubprogramDIE(DISubprogram(Entity));
661 else if (Entity.isType())
662 EntityDie = getOrCreateTypeDIE(DIType(Entity));
663 else if (Entity.isGlobalVariable())
664 EntityDie = getOrCreateGlobalVariableDIE(DIGlobalVariable(Entity));
666 EntityDie = getDIE(Entity);
668 addSourceLine(*IMDie, Module.getLineNumber(),
669 Module.getContext().getFilename(),
670 Module.getContext().getDirectory());
671 addDIEEntry(*IMDie, dwarf::DW_AT_import, *EntityDie);
672 StringRef Name = Module.getName();
674 addString(*IMDie, dwarf::DW_AT_name, Name);
679 void DwarfCompileUnit::finishSubprogramDefinition(DISubprogram SP) {
681 if (DIE *AbsSPDIE = DU->getAbstractSPDies().lookup(SP)) {
683 // If this subprogram has an abstract definition, reference that
684 addDIEEntry(*D, dwarf::DW_AT_abstract_origin, *AbsSPDIE);
686 if (!D && !includeMinimalInlineScopes())
687 // Lazily construct the subprogram if we didn't see either concrete or
688 // inlined versions during codegen. (except in -gmlt ^ where we want
689 // to omit these entirely)
690 D = getOrCreateSubprogramDIE(SP);
692 // And attach the attributes
693 applySubprogramAttributesToDefinition(SP, *D);
696 void DwarfCompileUnit::collectDeadVariables(DISubprogram SP) {
697 assert(SP.isSubprogram() && "CU's subprogram list contains a non-subprogram");
698 assert(SP.isDefinition() &&
699 "CU's subprogram list contains a subprogram declaration");
700 DIArray Variables = SP.getVariables();
701 if (Variables.getNumElements() == 0)
704 DIE *SPDIE = DU->getAbstractSPDies().lookup(SP);
708 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) {
709 DIVariable DV(Variables.getElement(vi));
710 assert(DV.isVariable());
711 DbgVariable NewVar(DV, DIExpression(), DD);
712 auto VariableDie = constructVariableDIE(NewVar);
713 applyVariableAttributes(NewVar, *VariableDie);
714 SPDIE->addChild(std::move(VariableDie));
718 void DwarfCompileUnit::emitHeader(bool UseOffsets) {
719 // Don't bother labeling the .dwo unit, as its offset isn't used.
721 LabelBegin = Asm->createTempSymbol("cu_begin", getUniqueID());
722 Asm->OutStreamer.EmitLabel(LabelBegin);
725 DwarfUnit::emitHeader(UseOffsets);
728 /// addGlobalName - Add a new global name to the compile unit.
729 void DwarfCompileUnit::addGlobalName(StringRef Name, DIE &Die,
731 if (includeMinimalInlineScopes())
733 std::string FullName = getParentContextString(Context) + Name.str();
734 GlobalNames[FullName] = &Die;
737 /// Add a new global type to the unit.
738 void DwarfCompileUnit::addGlobalType(DIType Ty, const DIE &Die,
740 if (includeMinimalInlineScopes())
742 std::string FullName = getParentContextString(Context) + Ty.getName().str();
743 GlobalTypes[FullName] = &Die;
746 /// addVariableAddress - Add DW_AT_location attribute for a
747 /// DbgVariable based on provided MachineLocation.
748 void DwarfCompileUnit::addVariableAddress(const DbgVariable &DV, DIE &Die,
749 MachineLocation Location) {
750 if (DV.variableHasComplexAddress())
751 addComplexAddress(DV, Die, dwarf::DW_AT_location, Location);
752 else if (DV.isBlockByrefVariable())
753 addBlockByrefAddress(DV, Die, dwarf::DW_AT_location, Location);
755 addAddress(Die, dwarf::DW_AT_location, Location);
758 /// Add an address attribute to a die based on the location provided.
759 void DwarfCompileUnit::addAddress(DIE &Die, dwarf::Attribute Attribute,
760 const MachineLocation &Location) {
761 DIELoc *Loc = new (DIEValueAllocator) DIELoc();
764 if (Location.isReg())
765 validReg = addRegisterOpPiece(*Loc, Location.getReg());
767 validReg = addRegisterOffset(*Loc, Location.getReg(), Location.getOffset());
772 // Now attach the location information to the DIE.
773 addBlock(Die, Attribute, Loc);
776 /// Start with the address based on the location provided, and generate the
777 /// DWARF information necessary to find the actual variable given the extra
778 /// address information encoded in the DbgVariable, starting from the starting
779 /// location. Add the DWARF information to the die.
780 void DwarfCompileUnit::addComplexAddress(const DbgVariable &DV, DIE &Die,
781 dwarf::Attribute Attribute,
782 const MachineLocation &Location) {
783 DIELoc *Loc = new (DIEValueAllocator) DIELoc();
784 DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc);
785 assert(DV.getExpression().size() == 1);
786 DIExpression Expr = DV.getExpression().back();
788 if (Location.getOffset()) {
789 ValidReg = DwarfExpr.AddMachineRegIndirect(Location.getReg(),
790 Location.getOffset());
792 DwarfExpr.AddExpression(Expr.begin(), Expr.end());
794 ValidReg = DwarfExpr.AddMachineRegExpression(Expr, Location.getReg());
796 // Now attach the location information to the DIE.
798 addBlock(Die, Attribute, Loc);
801 /// Add a Dwarf loclistptr attribute data and value.
802 void DwarfCompileUnit::addLocationList(DIE &Die, dwarf::Attribute Attribute,
804 DIEValue *Value = new (DIEValueAllocator) DIELocList(Index);
805 dwarf::Form Form = DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
806 : dwarf::DW_FORM_data4;
807 Die.addValue(Attribute, Form, Value);
810 void DwarfCompileUnit::applyVariableAttributes(const DbgVariable &Var,
812 StringRef Name = Var.getName();
814 addString(VariableDie, dwarf::DW_AT_name, Name);
815 addSourceLine(VariableDie, Var.getVariable());
816 addType(VariableDie, Var.getType());
817 if (Var.isArtificial())
818 addFlag(VariableDie, dwarf::DW_AT_artificial);
821 /// Add a Dwarf expression attribute data and value.
822 void DwarfCompileUnit::addExpr(DIELoc &Die, dwarf::Form Form,
823 const MCExpr *Expr) {
824 DIEValue *Value = new (DIEValueAllocator) DIEExpr(Expr);
825 Die.addValue((dwarf::Attribute)0, Form, Value);
828 void DwarfCompileUnit::applySubprogramAttributesToDefinition(DISubprogram SP,
830 DISubprogram SPDecl = SP.getFunctionDeclaration();
831 DIScope Context = resolve(SPDecl ? SPDecl.getContext() : SP.getContext());
832 applySubprogramAttributes(SP, SPDie, includeMinimalInlineScopes());
833 addGlobalName(SP.getName(), SPDie, Context);
836 bool DwarfCompileUnit::isDwoUnit() const {
837 return DD->useSplitDwarf() && Skeleton;
840 bool DwarfCompileUnit::includeMinimalInlineScopes() const {
841 return getCUNode().getEmissionKind() == DIBuilder::LineTablesOnly ||
842 (DD->useSplitDwarf() && !Skeleton);
844 } // end llvm namespace