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 // Return const expression if value is a GEP to access merged global
78 // i8* getelementptr ({ i8, i8, i8, i8 }* @_MergedGlobals, i32 0, i32 0)
79 static const ConstantExpr *getMergedGlobalExpr(const Value *V) {
80 const ConstantExpr *CE = dyn_cast_or_null<ConstantExpr>(V);
81 if (!CE || CE->getNumOperands() != 3 ||
82 CE->getOpcode() != Instruction::GetElementPtr)
85 // First operand points to a global struct.
86 Value *Ptr = CE->getOperand(0);
87 GlobalValue *GV = dyn_cast<GlobalValue>(Ptr);
88 if (!GV || !isa<StructType>(GV->getValueType()))
91 // Second operand is zero.
92 const ConstantInt *CI = dyn_cast_or_null<ConstantInt>(CE->getOperand(1));
93 if (!CI || !CI->isZero())
96 // Third operand is offset.
97 if (!isa<ConstantInt>(CE->getOperand(2)))
103 /// getOrCreateGlobalVariableDIE - get or create global variable DIE.
104 DIE *DwarfCompileUnit::getOrCreateGlobalVariableDIE(
105 const DIGlobalVariable *GV) {
106 // Check for pre-existence.
107 if (DIE *Die = getDIE(GV))
112 auto *GVContext = GV->getScope();
113 auto *GTy = DD->resolve(GV->getType());
115 // Construct the context before querying for the existence of the DIE in
116 // case such construction creates the DIE.
117 DIE *ContextDIE = getOrCreateContextDIE(GVContext);
120 DIE *VariableDIE = &createAndAddDIE(GV->getTag(), *ContextDIE, GV);
121 DIScope *DeclContext;
122 if (auto *SDMDecl = GV->getStaticDataMemberDeclaration()) {
123 DeclContext = resolve(SDMDecl->getScope());
124 assert(SDMDecl->isStaticMember() && "Expected static member decl");
125 assert(GV->isDefinition());
126 // We need the declaration DIE that is in the static member's class.
127 DIE *VariableSpecDIE = getOrCreateStaticMemberDIE(SDMDecl);
128 addDIEEntry(*VariableDIE, dwarf::DW_AT_specification, *VariableSpecDIE);
130 DeclContext = GV->getScope();
131 // Add name and type.
132 addString(*VariableDIE, dwarf::DW_AT_name, GV->getDisplayName());
133 addType(*VariableDIE, GTy);
136 if (!GV->isLocalToUnit())
137 addFlag(*VariableDIE, dwarf::DW_AT_external);
139 // Add line number info.
140 addSourceLine(*VariableDIE, GV);
143 if (!GV->isDefinition())
144 addFlag(*VariableDIE, dwarf::DW_AT_declaration);
146 addGlobalName(GV->getName(), *VariableDIE, DeclContext);
149 bool addToAccelTable = false;
150 if (auto *Global = dyn_cast_or_null<GlobalVariable>(GV->getVariable())) {
151 // We cannot describe the location of dllimport'd variables: the computation
152 // of their address requires loads from the IAT.
153 if (!Global->hasDLLImportStorageClass()) {
154 addToAccelTable = true;
155 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
156 const MCSymbol *Sym = Asm->getSymbol(Global);
157 if (Global->isThreadLocal()) {
158 if (Asm->TM.Options.EmulatedTLS) {
159 // TODO: add debug info for emulated thread local mode.
161 // FIXME: Make this work with -gsplit-dwarf.
162 unsigned PointerSize = Asm->getDataLayout().getPointerSize();
163 assert((PointerSize == 4 || PointerSize == 8) &&
164 "Add support for other sizes if necessary");
165 // Based on GCC's support for TLS:
166 if (!DD->useSplitDwarf()) {
167 // 1) Start with a constNu of the appropriate pointer size
168 addUInt(*Loc, dwarf::DW_FORM_data1, PointerSize == 4
169 ? dwarf::DW_OP_const4u
170 : dwarf::DW_OP_const8u);
171 // 2) containing the (relocated) offset of the TLS variable
172 // within the module's TLS block.
173 addExpr(*Loc, dwarf::DW_FORM_udata,
174 Asm->getObjFileLowering().getDebugThreadLocalSymbol(Sym));
176 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_GNU_const_index);
177 addUInt(*Loc, dwarf::DW_FORM_udata,
178 DD->getAddressPool().getIndex(Sym, /* TLS */ true));
180 // 3) followed by an OP to make the debugger do a TLS lookup.
181 addUInt(*Loc, dwarf::DW_FORM_data1,
182 DD->useGNUTLSOpcode() ? dwarf::DW_OP_GNU_push_tls_address
183 : dwarf::DW_OP_form_tls_address);
186 DD->addArangeLabel(SymbolCU(this, Sym));
187 addOpAddress(*Loc, Sym);
190 addBlock(*VariableDIE, dwarf::DW_AT_location, Loc);
191 if (DD->useAllLinkageNames())
192 addLinkageName(*VariableDIE, GV->getLinkageName());
194 } else if (const ConstantInt *CI =
195 dyn_cast_or_null<ConstantInt>(GV->getVariable())) {
196 addConstantValue(*VariableDIE, CI, GTy);
197 } else if (const ConstantExpr *CE = getMergedGlobalExpr(GV->getVariable())) {
198 auto *Ptr = cast<GlobalValue>(CE->getOperand(0));
199 if (!Ptr->hasDLLImportStorageClass()) {
200 addToAccelTable = true;
201 // GV is a merged global.
202 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
203 MCSymbol *Sym = Asm->getSymbol(Ptr);
204 DD->addArangeLabel(SymbolCU(this, Sym));
205 addOpAddress(*Loc, Sym);
206 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
207 SmallVector<Value *, 3> Idx(CE->op_begin() + 1, CE->op_end());
208 addUInt(*Loc, dwarf::DW_FORM_udata,
209 Asm->getDataLayout().getIndexedOffsetInType(Ptr->getValueType(),
211 addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_plus);
212 addBlock(*VariableDIE, dwarf::DW_AT_location, Loc);
216 if (addToAccelTable) {
217 DD->addAccelName(GV->getName(), *VariableDIE);
219 // If the linkage name is different than the name, go ahead and output
220 // that as well into the name table.
221 if (GV->getLinkageName() != "" && GV->getName() != GV->getLinkageName())
222 DD->addAccelName(GV->getLinkageName(), *VariableDIE);
228 void DwarfCompileUnit::addRange(RangeSpan Range) {
229 bool SameAsPrevCU = this == DD->getPrevCU();
231 // If we have no current ranges just add the range and return, otherwise,
232 // check the current section and CU against the previous section and CU we
233 // emitted into and the subprogram was contained within. If these are the
234 // same then extend our current range, otherwise add this as a new range.
235 if (CURanges.empty() || !SameAsPrevCU ||
236 (&CURanges.back().getEnd()->getSection() !=
237 &Range.getEnd()->getSection())) {
238 CURanges.push_back(Range);
242 CURanges.back().setEnd(Range.getEnd());
246 DwarfCompileUnit::addSectionLabel(DIE &Die, dwarf::Attribute Attribute,
247 const MCSymbol *Label, const MCSymbol *Sec) {
248 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
249 return addLabel(Die, Attribute,
250 DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
251 : dwarf::DW_FORM_data4,
253 return addSectionDelta(Die, Attribute, Label, Sec);
256 void DwarfCompileUnit::initStmtList() {
257 // Define start line table label for each Compile Unit.
258 MCSymbol *LineTableStartSym =
259 Asm->OutStreamer->getDwarfLineTableSymbol(getUniqueID());
261 // DW_AT_stmt_list is a offset of line number information for this
262 // compile unit in debug_line section. For split dwarf this is
263 // left in the skeleton CU and so not included.
264 // The line table entries are not always emitted in assembly, so it
265 // is not okay to use line_table_start here.
266 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
268 addSectionLabel(UnitDie, dwarf::DW_AT_stmt_list, LineTableStartSym,
269 TLOF.getDwarfLineSection()->getBeginSymbol());
272 void DwarfCompileUnit::applyStmtList(DIE &D) {
273 D.addValue(DIEValueAllocator, *StmtListValue);
276 void DwarfCompileUnit::attachLowHighPC(DIE &D, const MCSymbol *Begin,
277 const MCSymbol *End) {
278 assert(Begin && "Begin label should not be null!");
279 assert(End && "End label should not be null!");
280 assert(Begin->isDefined() && "Invalid starting label");
281 assert(End->isDefined() && "Invalid end label");
283 addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
284 if (DD->getDwarfVersion() < 4)
285 addLabelAddress(D, dwarf::DW_AT_high_pc, End);
287 addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
290 // Find DIE for the given subprogram and attach appropriate DW_AT_low_pc
291 // and DW_AT_high_pc attributes. If there are global variables in this
292 // scope then create and insert DIEs for these variables.
293 DIE &DwarfCompileUnit::updateSubprogramScopeDIE(const DISubprogram *SP) {
294 DIE *SPDie = getOrCreateSubprogramDIE(SP, includeMinimalInlineScopes());
296 attachLowHighPC(*SPDie, Asm->getFunctionBegin(), Asm->getFunctionEnd());
297 if (DD->useAppleExtensionAttributes() &&
298 !DD->getCurrentFunction()->getTarget().Options.DisableFramePointerElim(
299 *DD->getCurrentFunction()))
300 addFlag(*SPDie, dwarf::DW_AT_APPLE_omit_frame_ptr);
302 // Only include DW_AT_frame_base in full debug info
303 if (!includeMinimalInlineScopes()) {
304 const TargetRegisterInfo *RI = Asm->MF->getSubtarget().getRegisterInfo();
305 MachineLocation Location(RI->getFrameRegister(*Asm->MF));
306 if (RI->isPhysicalRegister(Location.getReg()))
307 addAddress(*SPDie, dwarf::DW_AT_frame_base, Location);
310 // Add name to the name table, we do this here because we're guaranteed
311 // to have concrete versions of our DW_TAG_subprogram nodes.
312 DD->addSubprogramNames(SP, *SPDie);
317 // Construct a DIE for this scope.
318 void DwarfCompileUnit::constructScopeDIE(
319 LexicalScope *Scope, SmallVectorImpl<DIE *> &FinalChildren) {
320 if (!Scope || !Scope->getScopeNode())
323 auto *DS = Scope->getScopeNode();
325 assert((Scope->getInlinedAt() || !isa<DISubprogram>(DS)) &&
326 "Only handle inlined subprograms here, use "
327 "constructSubprogramScopeDIE for non-inlined "
330 SmallVector<DIE *, 8> Children;
332 // We try to create the scope DIE first, then the children DIEs. This will
333 // avoid creating un-used children then removing them later when we find out
334 // the scope DIE is null.
336 if (Scope->getParent() && isa<DISubprogram>(DS)) {
337 ScopeDIE = constructInlinedScopeDIE(Scope);
340 // We create children when the scope DIE is not null.
341 createScopeChildrenDIE(Scope, Children);
343 // Early exit when we know the scope DIE is going to be null.
344 if (DD->isLexicalScopeDIENull(Scope))
347 unsigned ChildScopeCount;
349 // We create children here when we know the scope DIE is not going to be
350 // null and the children will be added to the scope DIE.
351 createScopeChildrenDIE(Scope, Children, &ChildScopeCount);
353 // Skip imported directives in gmlt-like data.
354 if (!includeMinimalInlineScopes()) {
355 // There is no need to emit empty lexical block DIE.
356 for (const auto *IE : ImportedEntities[DS])
358 constructImportedEntityDIE(cast<DIImportedEntity>(IE)));
361 // If there are only other scopes as children, put them directly in the
362 // parent instead, as this scope would serve no purpose.
363 if (Children.size() == ChildScopeCount) {
364 FinalChildren.insert(FinalChildren.end(),
365 std::make_move_iterator(Children.begin()),
366 std::make_move_iterator(Children.end()));
369 ScopeDIE = constructLexicalScopeDIE(Scope);
370 assert(ScopeDIE && "Scope DIE should not be null.");
374 for (auto &I : Children)
375 ScopeDIE->addChild(std::move(I));
377 FinalChildren.push_back(std::move(ScopeDIE));
381 DwarfCompileUnit::addSectionDelta(DIE &Die, dwarf::Attribute Attribute,
382 const MCSymbol *Hi, const MCSymbol *Lo) {
383 return Die.addValue(DIEValueAllocator, Attribute,
384 DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
385 : dwarf::DW_FORM_data4,
386 new (DIEValueAllocator) DIEDelta(Hi, Lo));
389 void DwarfCompileUnit::addScopeRangeList(DIE &ScopeDIE,
390 SmallVector<RangeSpan, 2> Range) {
391 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
393 // Emit offset in .debug_range as a relocatable label. emitDIE will handle
394 // emitting it appropriately.
395 const MCSymbol *RangeSectionSym =
396 TLOF.getDwarfRangesSection()->getBeginSymbol();
398 RangeSpanList List(Asm->createTempSymbol("debug_ranges"), std::move(Range));
400 // Under fission, ranges are specified by constant offsets relative to the
401 // CU's DW_AT_GNU_ranges_base.
403 addSectionDelta(ScopeDIE, dwarf::DW_AT_ranges, List.getSym(),
406 addSectionLabel(ScopeDIE, dwarf::DW_AT_ranges, List.getSym(),
409 // Add the range list to the set of ranges to be emitted.
410 (Skeleton ? Skeleton : this)->CURangeLists.push_back(std::move(List));
413 void DwarfCompileUnit::attachRangesOrLowHighPC(
414 DIE &Die, SmallVector<RangeSpan, 2> Ranges) {
415 if (Ranges.size() == 1) {
416 const auto &single = Ranges.front();
417 attachLowHighPC(Die, single.getStart(), single.getEnd());
419 addScopeRangeList(Die, std::move(Ranges));
422 void DwarfCompileUnit::attachRangesOrLowHighPC(
423 DIE &Die, const SmallVectorImpl<InsnRange> &Ranges) {
424 SmallVector<RangeSpan, 2> List;
425 List.reserve(Ranges.size());
426 for (const InsnRange &R : Ranges)
427 List.push_back(RangeSpan(DD->getLabelBeforeInsn(R.first),
428 DD->getLabelAfterInsn(R.second)));
429 attachRangesOrLowHighPC(Die, std::move(List));
432 // This scope represents inlined body of a function. Construct DIE to
433 // represent this concrete inlined copy of the function.
434 DIE *DwarfCompileUnit::constructInlinedScopeDIE(LexicalScope *Scope) {
435 assert(Scope->getScopeNode());
436 auto *DS = Scope->getScopeNode();
437 auto *InlinedSP = getDISubprogram(DS);
438 // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram
439 // was inlined from another compile unit.
440 DIE *OriginDIE = DU->getAbstractSPDies()[InlinedSP];
441 assert(OriginDIE && "Unable to find original DIE for an inlined subprogram.");
443 auto ScopeDIE = DIE::get(DIEValueAllocator, dwarf::DW_TAG_inlined_subroutine);
444 addDIEEntry(*ScopeDIE, dwarf::DW_AT_abstract_origin, *OriginDIE);
446 attachRangesOrLowHighPC(*ScopeDIE, Scope->getRanges());
448 // Add the call site information to the DIE.
449 const DILocation *IA = Scope->getInlinedAt();
450 addUInt(*ScopeDIE, dwarf::DW_AT_call_file, None,
451 getOrCreateSourceID(IA->getFilename(), IA->getDirectory()));
452 addUInt(*ScopeDIE, dwarf::DW_AT_call_line, None, IA->getLine());
453 if (IA->getDiscriminator())
454 addUInt(*ScopeDIE, dwarf::DW_AT_GNU_discriminator, None,
455 IA->getDiscriminator());
457 // Add name to the name table, we do this here because we're guaranteed
458 // to have concrete versions of our DW_TAG_inlined_subprogram nodes.
459 DD->addSubprogramNames(InlinedSP, *ScopeDIE);
464 // Construct new DW_TAG_lexical_block for this scope and attach
465 // DW_AT_low_pc/DW_AT_high_pc labels.
466 DIE *DwarfCompileUnit::constructLexicalScopeDIE(LexicalScope *Scope) {
467 if (DD->isLexicalScopeDIENull(Scope))
470 auto ScopeDIE = DIE::get(DIEValueAllocator, dwarf::DW_TAG_lexical_block);
471 if (Scope->isAbstractScope())
474 attachRangesOrLowHighPC(*ScopeDIE, Scope->getRanges());
479 /// constructVariableDIE - Construct a DIE for the given DbgVariable.
480 DIE *DwarfCompileUnit::constructVariableDIE(DbgVariable &DV, bool Abstract) {
481 auto D = constructVariableDIEImpl(DV, Abstract);
486 DIE *DwarfCompileUnit::constructVariableDIEImpl(const DbgVariable &DV,
488 // Define variable debug information entry.
489 auto VariableDie = DIE::get(DIEValueAllocator, DV.getTag());
492 applyVariableAttributes(DV, *VariableDie);
496 // Add variable address.
498 unsigned Offset = DV.getDebugLocListIndex();
500 addLocationList(*VariableDie, dwarf::DW_AT_location, Offset);
504 // Check if variable is described by a DBG_VALUE instruction.
505 if (const MachineInstr *DVInsn = DV.getMInsn()) {
506 assert(DVInsn->getNumOperands() == 4);
507 if (DVInsn->getOperand(0).isReg()) {
508 const MachineOperand RegOp = DVInsn->getOperand(0);
509 // If the second operand is an immediate, this is an indirect value.
510 if (DVInsn->getOperand(1).isImm()) {
511 MachineLocation Location(RegOp.getReg(),
512 DVInsn->getOperand(1).getImm());
513 addVariableAddress(DV, *VariableDie, Location);
514 } else if (RegOp.getReg())
515 addVariableAddress(DV, *VariableDie, MachineLocation(RegOp.getReg()));
516 } else if (DVInsn->getOperand(0).isImm()) {
517 // This variable is described by a single constant.
518 // Check whether it has a DIExpression.
519 auto *Expr = DV.getSingleExpression();
520 if (Expr && Expr->getNumElements()) {
521 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
522 DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc);
523 // If there is an expression, emit raw unsigned bytes.
524 DwarfExpr.AddUnsignedConstant(DVInsn->getOperand(0).getImm());
525 DwarfExpr.AddExpression(Expr->expr_op_begin(), Expr->expr_op_end());
526 addBlock(*VariableDie, dwarf::DW_AT_location, Loc);
528 addConstantValue(*VariableDie, DVInsn->getOperand(0), DV.getType());
529 } else if (DVInsn->getOperand(0).isFPImm())
530 addConstantFPValue(*VariableDie, DVInsn->getOperand(0));
531 else if (DVInsn->getOperand(0).isCImm())
532 addConstantValue(*VariableDie, DVInsn->getOperand(0).getCImm(),
538 // .. else use frame index.
539 if (DV.getFrameIndex().empty())
542 auto Expr = DV.getExpression().begin();
543 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
544 DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc);
545 for (auto FI : DV.getFrameIndex()) {
546 unsigned FrameReg = 0;
547 const TargetFrameLowering *TFI = Asm->MF->getSubtarget().getFrameLowering();
548 int Offset = TFI->getFrameIndexReference(*Asm->MF, FI, FrameReg);
549 assert(Expr != DV.getExpression().end() && "Wrong number of expressions");
550 DwarfExpr.AddMachineRegIndirect(*Asm->MF->getSubtarget().getRegisterInfo(),
552 DwarfExpr.AddExpression((*Expr)->expr_op_begin(), (*Expr)->expr_op_end());
555 addBlock(*VariableDie, dwarf::DW_AT_location, Loc);
560 DIE *DwarfCompileUnit::constructVariableDIE(DbgVariable &DV,
561 const LexicalScope &Scope,
562 DIE *&ObjectPointer) {
563 auto Var = constructVariableDIE(DV, Scope.isAbstractScope());
564 if (DV.isObjectPointer())
569 DIE *DwarfCompileUnit::createScopeChildrenDIE(LexicalScope *Scope,
570 SmallVectorImpl<DIE *> &Children,
571 unsigned *ChildScopeCount) {
572 DIE *ObjectPointer = nullptr;
574 for (DbgVariable *DV : DU->getScopeVariables().lookup(Scope))
575 Children.push_back(constructVariableDIE(*DV, *Scope, ObjectPointer));
577 unsigned ChildCountWithoutScopes = Children.size();
579 for (LexicalScope *LS : Scope->getChildren())
580 constructScopeDIE(LS, Children);
583 *ChildScopeCount = Children.size() - ChildCountWithoutScopes;
585 return ObjectPointer;
588 void DwarfCompileUnit::constructSubprogramScopeDIE(LexicalScope *Scope) {
589 assert(Scope && Scope->getScopeNode());
590 assert(!Scope->getInlinedAt());
591 assert(!Scope->isAbstractScope());
592 auto *Sub = cast<DISubprogram>(Scope->getScopeNode());
594 DD->getProcessedSPNodes().insert(Sub);
596 DIE &ScopeDIE = updateSubprogramScopeDIE(Sub);
598 // If this is a variadic function, add an unspecified parameter.
599 DITypeRefArray FnArgs = Sub->getType()->getTypeArray();
601 // Collect lexical scope children first.
602 // ObjectPointer might be a local (non-argument) local variable if it's a
603 // block's synthetic this pointer.
604 if (DIE *ObjectPointer = createAndAddScopeChildren(Scope, ScopeDIE))
605 addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer);
607 // If we have a single element of null, it is a function that returns void.
608 // If we have more than one elements and the last one is null, it is a
609 // variadic function.
610 if (FnArgs.size() > 1 && !FnArgs[FnArgs.size() - 1] &&
611 !includeMinimalInlineScopes())
613 DIE::get(DIEValueAllocator, dwarf::DW_TAG_unspecified_parameters));
616 DIE *DwarfCompileUnit::createAndAddScopeChildren(LexicalScope *Scope,
618 // We create children when the scope DIE is not null.
619 SmallVector<DIE *, 8> Children;
620 DIE *ObjectPointer = createScopeChildrenDIE(Scope, Children);
623 for (auto &I : Children)
624 ScopeDIE.addChild(std::move(I));
626 return ObjectPointer;
629 void DwarfCompileUnit::constructAbstractSubprogramScopeDIE(
630 LexicalScope *Scope) {
631 DIE *&AbsDef = DU->getAbstractSPDies()[Scope->getScopeNode()];
635 auto *SP = cast<DISubprogram>(Scope->getScopeNode());
639 if (includeMinimalInlineScopes())
640 ContextDIE = &getUnitDie();
641 // Some of this is duplicated from DwarfUnit::getOrCreateSubprogramDIE, with
642 // the important distinction that the debug node is not associated with the
643 // DIE (since the debug node will be associated with the concrete DIE, if
644 // any). It could be refactored to some common utility function.
645 else if (auto *SPDecl = SP->getDeclaration()) {
646 ContextDIE = &getUnitDie();
647 getOrCreateSubprogramDIE(SPDecl);
649 ContextDIE = getOrCreateContextDIE(resolve(SP->getScope()));
651 // Passing null as the associated node because the abstract definition
652 // shouldn't be found by lookup.
653 AbsDef = &createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, nullptr);
654 applySubprogramAttributesToDefinition(SP, *AbsDef);
656 if (!includeMinimalInlineScopes())
657 addUInt(*AbsDef, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
658 if (DIE *ObjectPointer = createAndAddScopeChildren(Scope, *AbsDef))
659 addDIEEntry(*AbsDef, dwarf::DW_AT_object_pointer, *ObjectPointer);
662 DIE *DwarfCompileUnit::constructImportedEntityDIE(
663 const DIImportedEntity *Module) {
664 DIE *IMDie = DIE::get(DIEValueAllocator, (dwarf::Tag)Module->getTag());
665 insertDIE(Module, IMDie);
667 auto *Entity = resolve(Module->getEntity());
668 if (auto *NS = dyn_cast<DINamespace>(Entity))
669 EntityDie = getOrCreateNameSpace(NS);
670 else if (auto *M = dyn_cast<DIModule>(Entity))
671 EntityDie = getOrCreateModule(M);
672 else if (auto *SP = dyn_cast<DISubprogram>(Entity))
673 EntityDie = getOrCreateSubprogramDIE(SP);
674 else if (auto *T = dyn_cast<DIType>(Entity))
675 EntityDie = getOrCreateTypeDIE(T);
676 else if (auto *GV = dyn_cast<DIGlobalVariable>(Entity))
677 EntityDie = getOrCreateGlobalVariableDIE(GV);
679 EntityDie = getDIE(Entity);
681 addSourceLine(*IMDie, Module->getLine(), Module->getScope()->getFilename(),
682 Module->getScope()->getDirectory());
683 addDIEEntry(*IMDie, dwarf::DW_AT_import, *EntityDie);
684 StringRef Name = Module->getName();
686 addString(*IMDie, dwarf::DW_AT_name, Name);
691 void DwarfCompileUnit::finishSubprogramDefinition(const DISubprogram *SP) {
693 if (DIE *AbsSPDIE = DU->getAbstractSPDies().lookup(SP)) {
695 // If this subprogram has an abstract definition, reference that
696 addDIEEntry(*D, dwarf::DW_AT_abstract_origin, *AbsSPDIE);
698 if (!D && !includeMinimalInlineScopes())
699 // Lazily construct the subprogram if we didn't see either concrete or
700 // inlined versions during codegen. (except in -gmlt ^ where we want
701 // to omit these entirely)
702 D = getOrCreateSubprogramDIE(SP);
704 // And attach the attributes
705 applySubprogramAttributesToDefinition(SP, *D);
709 void DwarfCompileUnit::emitHeader(bool UseOffsets) {
710 // Don't bother labeling the .dwo unit, as its offset isn't used.
712 LabelBegin = Asm->createTempSymbol("cu_begin");
713 Asm->OutStreamer->EmitLabel(LabelBegin);
716 DwarfUnit::emitHeader(UseOffsets);
719 /// addGlobalName - Add a new global name to the compile unit.
720 void DwarfCompileUnit::addGlobalName(StringRef Name, DIE &Die,
721 const DIScope *Context) {
722 if (includeMinimalInlineScopes())
724 std::string FullName = getParentContextString(Context) + Name.str();
725 GlobalNames[FullName] = &Die;
728 /// Add a new global type to the unit.
729 void DwarfCompileUnit::addGlobalType(const DIType *Ty, const DIE &Die,
730 const DIScope *Context) {
731 if (includeMinimalInlineScopes())
733 std::string FullName = getParentContextString(Context) + Ty->getName().str();
734 GlobalTypes[FullName] = &Die;
737 /// addVariableAddress - Add DW_AT_location attribute for a
738 /// DbgVariable based on provided MachineLocation.
739 void DwarfCompileUnit::addVariableAddress(const DbgVariable &DV, DIE &Die,
740 MachineLocation Location) {
741 if (DV.hasComplexAddress())
742 addComplexAddress(DV, Die, dwarf::DW_AT_location, Location);
743 else if (DV.isBlockByrefVariable())
744 addBlockByrefAddress(DV, Die, dwarf::DW_AT_location, Location);
746 addAddress(Die, dwarf::DW_AT_location, Location);
749 /// Add an address attribute to a die based on the location provided.
750 void DwarfCompileUnit::addAddress(DIE &Die, dwarf::Attribute Attribute,
751 const MachineLocation &Location) {
752 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
755 if (Location.isReg())
756 validReg = addRegisterOpPiece(*Loc, Location.getReg());
758 validReg = addRegisterOffset(*Loc, Location.getReg(), Location.getOffset());
763 // Now attach the location information to the DIE.
764 addBlock(Die, Attribute, Loc);
767 /// Start with the address based on the location provided, and generate the
768 /// DWARF information necessary to find the actual variable given the extra
769 /// address information encoded in the DbgVariable, starting from the starting
770 /// location. Add the DWARF information to the die.
771 void DwarfCompileUnit::addComplexAddress(const DbgVariable &DV, DIE &Die,
772 dwarf::Attribute Attribute,
773 const MachineLocation &Location) {
774 DIELoc *Loc = new (DIEValueAllocator) DIELoc;
775 DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc);
776 const DIExpression *Expr = DV.getSingleExpression();
778 const TargetRegisterInfo &TRI = *Asm->MF->getSubtarget().getRegisterInfo();
779 if (Location.getOffset()) {
780 ValidReg = DwarfExpr.AddMachineRegIndirect(TRI, Location.getReg(),
781 Location.getOffset());
783 DwarfExpr.AddExpression(Expr->expr_op_begin(), Expr->expr_op_end());
785 ValidReg = DwarfExpr.AddMachineRegExpression(TRI, Expr, Location.getReg());
787 // Now attach the location information to the DIE.
789 addBlock(Die, Attribute, Loc);
792 /// Add a Dwarf loclistptr attribute data and value.
793 void DwarfCompileUnit::addLocationList(DIE &Die, dwarf::Attribute Attribute,
795 dwarf::Form Form = DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset
796 : dwarf::DW_FORM_data4;
797 Die.addValue(DIEValueAllocator, Attribute, Form, DIELocList(Index));
800 void DwarfCompileUnit::applyVariableAttributes(const DbgVariable &Var,
802 StringRef Name = Var.getName();
804 addString(VariableDie, dwarf::DW_AT_name, Name);
805 addSourceLine(VariableDie, Var.getVariable());
806 addType(VariableDie, Var.getType());
807 if (Var.isArtificial())
808 addFlag(VariableDie, dwarf::DW_AT_artificial);
811 /// Add a Dwarf expression attribute data and value.
812 void DwarfCompileUnit::addExpr(DIELoc &Die, dwarf::Form Form,
813 const MCExpr *Expr) {
814 Die.addValue(DIEValueAllocator, (dwarf::Attribute)0, Form, DIEExpr(Expr));
817 void DwarfCompileUnit::applySubprogramAttributesToDefinition(
818 const DISubprogram *SP, DIE &SPDie) {
819 auto *SPDecl = SP->getDeclaration();
820 auto *Context = resolve(SPDecl ? SPDecl->getScope() : SP->getScope());
821 applySubprogramAttributes(SP, SPDie, includeMinimalInlineScopes());
822 addGlobalName(SP->getName(), SPDie, Context);
825 bool DwarfCompileUnit::isDwoUnit() const {
826 return DD->useSplitDwarf() && Skeleton;
829 bool DwarfCompileUnit::includeMinimalInlineScopes() const {
830 return getCUNode()->getEmissionKind() == DICompileUnit::LineTablesOnly ||
831 (DD->useSplitDwarf() && !Skeleton);
833 } // end llvm namespace