1 //===--- DebugInfo.cpp - Debug Information Helper Classes -----------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the helper classes used to build and interpret debug
11 // information in LLVM IR form.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/IR/DebugInfo.h"
16 #include "LLVMContextImpl.h"
17 #include "llvm/ADT/STLExtras.h"
18 #include "llvm/ADT/SmallPtrSet.h"
19 #include "llvm/ADT/SmallString.h"
20 #include "llvm/ADT/StringSwitch.h"
21 #include "llvm/Analysis/ValueTracking.h"
22 #include "llvm/IR/Constants.h"
23 #include "llvm/IR/DIBuilder.h"
24 #include "llvm/IR/DerivedTypes.h"
25 #include "llvm/IR/Instructions.h"
26 #include "llvm/IR/IntrinsicInst.h"
27 #include "llvm/IR/Intrinsics.h"
28 #include "llvm/IR/GVMaterializer.h"
29 #include "llvm/IR/Module.h"
30 #include "llvm/IR/ValueHandle.h"
31 #include "llvm/Support/Debug.h"
32 #include "llvm/Support/Dwarf.h"
33 #include "llvm/Support/raw_ostream.h"
35 using namespace llvm::dwarf;
37 //===----------------------------------------------------------------------===//
39 //===----------------------------------------------------------------------===//
41 unsigned DIDescriptor::getFlag(StringRef Flag) {
42 return StringSwitch<unsigned>(Flag)
43 #define HANDLE_DI_FLAG(ID, NAME) .Case("DIFlag" #NAME, Flag##NAME)
44 #include "llvm/IR/DebugInfoFlags.def"
48 const char *DIDescriptor::getFlagString(unsigned Flag) {
52 #define HANDLE_DI_FLAG(ID, NAME) \
54 return "DIFlag" #NAME;
55 #include "llvm/IR/DebugInfoFlags.def"
59 unsigned DIDescriptor::splitFlags(unsigned Flags,
60 SmallVectorImpl<unsigned> &SplitFlags) {
61 // Accessibility flags need to be specially handled, since they're packed
63 if (unsigned A = Flags & FlagAccessibility) {
65 SplitFlags.push_back(FlagPrivate);
66 else if (A == FlagProtected)
67 SplitFlags.push_back(FlagProtected);
69 SplitFlags.push_back(FlagPublic);
73 #define HANDLE_DI_FLAG(ID, NAME) \
74 if (unsigned Bit = Flags & ID) { \
75 SplitFlags.push_back(Bit); \
78 #include "llvm/IR/DebugInfoFlags.def"
83 static Metadata *getField(const MDNode *DbgNode, unsigned Elt) {
84 if (!DbgNode || Elt >= DbgNode->getNumOperands())
86 return DbgNode->getOperand(Elt);
89 static MDNode *getNodeField(const MDNode *DbgNode, unsigned Elt) {
90 return dyn_cast_or_null<MDNode>(getField(DbgNode, Elt));
93 DIDescriptor DIDescriptor::getDescriptorField(unsigned Elt) const {
94 MDNode *Field = getNodeField(DbgNode, Elt);
95 return DIDescriptor(Field);
98 /// \brief Return the size reported by the variable's type.
99 unsigned DIVariable::getSizeInBits(const DITypeIdentifierMap &Map) {
100 DIType Ty = getType().resolve(Map);
101 // Follow derived types until we reach a type that
102 // reports back a size.
103 while (Ty.isDerivedType() && !Ty.getSizeInBits()) {
104 DIDerivedType DT(&*Ty);
105 Ty = DT.getTypeDerivedFrom().resolve(Map);
107 assert(Ty.getSizeInBits() && "type with size 0");
108 return Ty.getSizeInBits();
111 bool DIExpression::isBitPiece() const {
112 unsigned N = getNumElements();
113 return N >=3 && getElement(N-3) == dwarf::DW_OP_bit_piece;
116 uint64_t DIExpression::getBitPieceOffset() const {
117 assert(isBitPiece() && "not a piece");
118 return getElement(getNumElements()-2);
121 uint64_t DIExpression::getBitPieceSize() const {
122 assert(isBitPiece() && "not a piece");
123 return getElement(getNumElements()-1);
126 DIExpression::iterator DIExpression::Operand::getNext() const {
131 //===----------------------------------------------------------------------===//
132 // Simple Descriptor Constructors and other Methods
133 //===----------------------------------------------------------------------===//
135 void DIDescriptor::replaceAllUsesWith(LLVMContext &, DIDescriptor D) {
136 assert(DbgNode && "Trying to replace an unverified type!");
137 assert(DbgNode->isTemporary() && "Expected temporary node");
138 TempMDNode Temp(get());
140 // Since we use a TrackingVH for the node, its easy for clients to manufacture
141 // legitimate situations where they want to replaceAllUsesWith() on something
142 // which, due to uniquing, has merged with the source. We shield clients from
143 // this detail by allowing a value to be replaced with replaceAllUsesWith()
145 if (Temp.get() == D.get()) {
146 DbgNode = MDNode::replaceWithUniqued(std::move(Temp));
150 Temp->replaceAllUsesWith(D.get());
154 void DIDescriptor::replaceAllUsesWith(MDNode *D) {
155 assert(DbgNode && "Trying to replace an unverified type!");
156 assert(DbgNode != D && "This replacement should always happen");
157 assert(DbgNode->isTemporary() && "Expected temporary node");
158 TempMDNode Node(get());
159 Node->replaceAllUsesWith(D);
163 /// \brief Check if a value can be a reference to a type.
164 static bool isTypeRef(const Metadata *MD) {
167 if (auto *S = dyn_cast<MDString>(MD))
168 return !S->getString().empty();
169 return isa<MDType>(MD);
172 /// \brief Check if a value can be a ScopeRef.
173 static bool isScopeRef(const Metadata *MD) {
176 if (auto *S = dyn_cast<MDString>(MD))
177 return !S->getString().empty();
178 return isa<MDScope>(MD);
181 /// \brief Check if a value can be a DescriptorRef.
182 static bool isDescriptorRef(const Metadata *MD) {
185 if (auto *S = dyn_cast<MDString>(MD))
186 return !S->getString().empty();
187 return isa<MDNode>(MD);
191 void DICompositeType::setArraysHelper(MDNode *Elements, MDNode *TParams) {
192 TypedTrackingMDRef<MDCompositeTypeBase> N(get());
194 N->replaceElements(cast<MDTuple>(Elements));
196 N->replaceTemplateParams(cast<MDTuple>(TParams));
200 DIScopeRef DIScope::getRef() const { return MDScopeRef::get(get()); }
202 void DICompositeType::setContainingType(DICompositeType ContainingType) {
203 TypedTrackingMDRef<MDCompositeTypeBase> N(get());
204 N->replaceVTableHolder(MDTypeRef::get(ContainingType));
208 bool DIVariable::isInlinedFnArgument(const Function *CurFn) {
209 assert(CurFn && "Invalid function");
210 if (!getContext().isSubprogram())
212 // This variable is not inlined function argument if its scope
213 // does not describe current function.
214 return !DISubprogram(getContext()).describes(CurFn);
217 Function *DISubprogram::getFunction() const {
219 if (auto *C = dyn_cast_or_null<ConstantAsMetadata>(N->getFunction()))
220 return dyn_cast<Function>(C->getValue());
224 bool DISubprogram::describes(const Function *F) {
225 assert(F && "Invalid function");
226 if (F == getFunction())
228 StringRef Name = getLinkageName();
231 if (F->getName() == Name)
236 GlobalVariable *DIGlobalVariable::getGlobal() const {
237 return dyn_cast_or_null<GlobalVariable>(getConstant());
240 DIScopeRef DIScope::getContext() const {
243 return DIType(DbgNode).getContext();
246 return DIScopeRef(DISubprogram(DbgNode).getContext());
248 if (isLexicalBlock())
249 return DIScopeRef(DILexicalBlock(DbgNode).getContext());
251 if (isLexicalBlockFile())
252 return DIScopeRef(DILexicalBlockFile(DbgNode).getContext());
255 return DIScopeRef(DINameSpace(DbgNode).getContext());
257 assert((isFile() || isCompileUnit()) && "Unhandled type of scope.");
258 return DIScopeRef(nullptr);
261 StringRef DIScope::getName() const {
263 return DIType(DbgNode).getName();
265 return DISubprogram(DbgNode).getName();
267 return DINameSpace(DbgNode).getName();
268 assert((isLexicalBlock() || isLexicalBlockFile() || isFile() ||
270 "Unhandled type of scope.");
274 StringRef DIScope::getFilename() const {
276 if (auto *F = N->getFile())
277 return F->getFilename();
281 StringRef DIScope::getDirectory() const {
283 if (auto *F = N->getFile())
284 return F->getDirectory();
288 void DICompileUnit::replaceSubprograms(DIArray Subprograms) {
289 get()->replaceSubprograms(cast_or_null<MDTuple>(Subprograms.get()));
292 void DICompileUnit::replaceGlobalVariables(DIArray GlobalVariables) {
293 get()->replaceGlobalVariables(cast_or_null<MDTuple>(GlobalVariables.get()));
296 DILocation DILocation::copyWithNewScope(LLVMContext &Ctx,
297 DILexicalBlockFile NewScope) {
298 assert(NewScope && "Expected valid scope");
300 const auto *Old = cast<MDLocation>(DbgNode);
301 return DILocation(MDLocation::get(Ctx, Old->getLine(), Old->getColumn(),
302 NewScope, Old->getInlinedAt()));
305 unsigned DILocation::computeNewDiscriminator(LLVMContext &Ctx) {
306 std::pair<const char *, unsigned> Key(getFilename().data(), getLineNumber());
307 return ++Ctx.pImpl->DiscriminatorTable[Key];
310 DIVariable llvm::createInlinedVariable(MDNode *DV, MDNode *InlinedScope,
311 LLVMContext &VMContext) {
312 return cast<MDLocalVariable>(DV)
313 ->withInline(cast_or_null<MDLocation>(InlinedScope));
316 DIVariable llvm::cleanseInlinedVariable(MDNode *DV, LLVMContext &VMContext) {
317 return cast<MDLocalVariable>(DV)->withoutInline();
320 DISubprogram llvm::getDISubprogram(const MDNode *Scope) {
321 if (auto *LocalScope = dyn_cast_or_null<MDLocalScope>(Scope))
322 return LocalScope->getSubprogram();
326 DISubprogram llvm::getDISubprogram(const Function *F) {
327 // We look for the first instr that has a debug annotation leading back to F.
328 for (auto &BB : *F) {
329 auto Inst = std::find_if(BB.begin(), BB.end(), [](const Instruction &Inst) {
330 return Inst.getDebugLoc();
332 if (Inst == BB.end())
334 DebugLoc DLoc = Inst->getDebugLoc();
335 const MDNode *Scope = DLoc.getInlinedAtScope();
336 DISubprogram Subprogram = getDISubprogram(Scope);
337 return Subprogram.describes(F) ? Subprogram : DISubprogram();
340 return DISubprogram();
343 DICompositeType llvm::getDICompositeType(DIType T) {
344 if (T.isCompositeType())
345 return DICompositeType(T);
347 if (T.isDerivedType()) {
348 // This function is currently used by dragonegg and dragonegg does
349 // not generate identifier for types, so using an empty map to resolve
350 // DerivedFrom should be fine.
351 DITypeIdentifierMap EmptyMap;
352 return getDICompositeType(
353 DIDerivedType(T).getTypeDerivedFrom().resolve(EmptyMap));
356 return DICompositeType();
360 llvm::generateDITypeIdentifierMap(const NamedMDNode *CU_Nodes) {
361 DITypeIdentifierMap Map;
362 for (unsigned CUi = 0, CUe = CU_Nodes->getNumOperands(); CUi != CUe; ++CUi) {
363 DICompileUnit CU(CU_Nodes->getOperand(CUi));
364 DIArray Retain = CU.getRetainedTypes();
365 for (unsigned Ti = 0, Te = Retain.getNumElements(); Ti != Te; ++Ti) {
366 if (!Retain.getElement(Ti).isCompositeType())
368 DICompositeType Ty(Retain.getElement(Ti));
369 if (MDString *TypeId = Ty.getIdentifier()) {
370 // Definition has priority over declaration.
371 // Try to insert (TypeId, Ty) to Map.
372 std::pair<DITypeIdentifierMap::iterator, bool> P =
373 Map.insert(std::make_pair(TypeId, Ty));
374 // If TypeId already exists in Map and this is a definition, replace
375 // whatever we had (declaration or definition) with the definition.
376 if (!P.second && !Ty.isForwardDecl())
377 P.first->second = Ty;
384 //===----------------------------------------------------------------------===//
385 // DebugInfoFinder implementations.
386 //===----------------------------------------------------------------------===//
388 void DebugInfoFinder::reset() {
395 TypeIdentifierMap.clear();
396 TypeMapInitialized = false;
399 void DebugInfoFinder::InitializeTypeMap(const Module &M) {
400 if (!TypeMapInitialized)
401 if (NamedMDNode *CU_Nodes = M.getNamedMetadata("llvm.dbg.cu")) {
402 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes);
403 TypeMapInitialized = true;
407 void DebugInfoFinder::processModule(const Module &M) {
408 InitializeTypeMap(M);
409 if (NamedMDNode *CU_Nodes = M.getNamedMetadata("llvm.dbg.cu")) {
410 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
411 DICompileUnit CU(CU_Nodes->getOperand(i));
413 DIArray GVs = CU.getGlobalVariables();
414 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i) {
415 DIGlobalVariable DIG(GVs.getElement(i));
416 if (addGlobalVariable(DIG)) {
417 processScope(DIG.getContext());
418 processType(DIG.getType().resolve(TypeIdentifierMap));
421 DIArray SPs = CU.getSubprograms();
422 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
423 processSubprogram(DISubprogram(SPs.getElement(i)));
424 DIArray EnumTypes = CU.getEnumTypes();
425 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i)
426 processType(DIType(EnumTypes.getElement(i)));
427 DIArray RetainedTypes = CU.getRetainedTypes();
428 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i)
429 processType(DIType(RetainedTypes.getElement(i)));
430 DIArray Imports = CU.getImportedEntities();
431 for (unsigned i = 0, e = Imports.getNumElements(); i != e; ++i) {
432 DIImportedEntity Import = DIImportedEntity(Imports.getElement(i));
435 DIDescriptor Entity = Import.getEntity().resolve(TypeIdentifierMap);
437 processType(DIType(Entity));
438 else if (Entity.isSubprogram())
439 processSubprogram(DISubprogram(Entity));
440 else if (Entity.isNameSpace())
441 processScope(DINameSpace(Entity).getContext());
447 void DebugInfoFinder::processLocation(const Module &M, DILocation Loc) {
450 InitializeTypeMap(M);
451 processScope(Loc.getScope());
452 processLocation(M, Loc.getOrigLocation());
455 void DebugInfoFinder::processType(DIType DT) {
458 processScope(DT.getContext().resolve(TypeIdentifierMap));
459 if (DT.isCompositeType()) {
460 DICompositeType DCT(DT);
461 processType(DCT.getTypeDerivedFrom().resolve(TypeIdentifierMap));
462 if (DT.isSubroutineType()) {
463 DITypeArray DTA = DISubroutineType(DT).getTypeArray();
464 for (unsigned i = 0, e = DTA.getNumElements(); i != e; ++i)
465 processType(DTA.getElement(i).resolve(TypeIdentifierMap));
468 DIArray DA = DCT.getElements();
469 for (unsigned i = 0, e = DA.getNumElements(); i != e; ++i) {
470 DIDescriptor D = DA.getElement(i);
472 processType(DIType(D));
473 else if (D.isSubprogram())
474 processSubprogram(DISubprogram(D));
476 } else if (DT.isDerivedType()) {
477 DIDerivedType DDT(DT);
478 processType(DDT.getTypeDerivedFrom().resolve(TypeIdentifierMap));
482 void DebugInfoFinder::processScope(DIScope Scope) {
483 if (Scope.isType()) {
488 if (Scope.isCompileUnit()) {
489 addCompileUnit(DICompileUnit(Scope));
492 if (Scope.isSubprogram()) {
493 processSubprogram(DISubprogram(Scope));
496 if (!addScope(Scope))
498 if (Scope.isLexicalBlock()) {
499 DILexicalBlock LB(Scope);
500 processScope(LB.getContext());
501 } else if (Scope.isNameSpace()) {
502 DINameSpace NS(Scope);
503 processScope(NS.getContext());
507 void DebugInfoFinder::processSubprogram(DISubprogram SP) {
508 if (!addSubprogram(SP))
510 processScope(SP.getContext().resolve(TypeIdentifierMap));
511 processType(SP.getType());
512 DIArray TParams = SP.getTemplateParams();
513 for (unsigned I = 0, E = TParams.getNumElements(); I != E; ++I) {
514 DIDescriptor Element = TParams.getElement(I);
515 if (Element.isTemplateTypeParameter()) {
516 DITemplateTypeParameter TType(Element);
517 processType(TType.getType().resolve(TypeIdentifierMap));
518 } else if (Element.isTemplateValueParameter()) {
519 DITemplateValueParameter TVal(Element);
520 processType(TVal.getType().resolve(TypeIdentifierMap));
525 void DebugInfoFinder::processDeclare(const Module &M,
526 const DbgDeclareInst *DDI) {
527 MDNode *N = dyn_cast<MDNode>(DDI->getVariable());
530 InitializeTypeMap(M);
533 if (!DV.isVariable())
536 if (!NodesSeen.insert(DV).second)
538 processScope(DIVariable(N).getContext());
539 processType(DIVariable(N).getType().resolve(TypeIdentifierMap));
542 void DebugInfoFinder::processValue(const Module &M, const DbgValueInst *DVI) {
543 MDNode *N = dyn_cast<MDNode>(DVI->getVariable());
546 InitializeTypeMap(M);
549 if (!DV.isVariable())
552 if (!NodesSeen.insert(DV).second)
554 processScope(DIVariable(N).getContext());
555 processType(DIVariable(N).getType().resolve(TypeIdentifierMap));
558 bool DebugInfoFinder::addType(DIType DT) {
562 if (!NodesSeen.insert(DT).second)
569 bool DebugInfoFinder::addCompileUnit(DICompileUnit CU) {
572 if (!NodesSeen.insert(CU).second)
579 bool DebugInfoFinder::addGlobalVariable(DIGlobalVariable DIG) {
583 if (!NodesSeen.insert(DIG).second)
590 bool DebugInfoFinder::addSubprogram(DISubprogram SP) {
594 if (!NodesSeen.insert(SP).second)
601 bool DebugInfoFinder::addScope(DIScope Scope) {
604 // FIXME: Ocaml binding generates a scope with no content, we treat it
606 if (Scope->getNumOperands() == 0)
608 if (!NodesSeen.insert(Scope).second)
610 Scopes.push_back(Scope);
614 //===----------------------------------------------------------------------===//
615 // DIDescriptor: dump routines for all descriptors.
616 //===----------------------------------------------------------------------===//
618 void DIDescriptor::dump() const {
623 void DIDescriptor::print(raw_ostream &OS) const {
629 static void printDebugLoc(DebugLoc DL, raw_ostream &CommentOS,
630 const LLVMContext &Ctx) {
634 DIScope Scope(DL.getScope());
635 assert(Scope.isScope() && "Scope of a DebugLoc should be a DIScope.");
636 // Omit the directory, because it's likely to be long and uninteresting.
637 CommentOS << Scope.getFilename();
638 CommentOS << ':' << DL.getLine();
639 if (DL.getCol() != 0)
640 CommentOS << ':' << DL.getCol();
642 DebugLoc InlinedAtDL = DL.getInlinedAt();
647 printDebugLoc(InlinedAtDL, CommentOS, Ctx);
651 void DIVariable::printExtendedName(raw_ostream &OS) const {
652 const LLVMContext &Ctx = DbgNode->getContext();
653 StringRef Res = getName();
655 OS << Res << "," << getLineNumber();
656 if (auto *InlinedAt = get()->getInlinedAt()) {
657 if (DebugLoc InlinedAtDL = InlinedAt) {
659 printDebugLoc(InlinedAtDL, OS, Ctx);
665 template <> DIRef<DIDescriptor>::DIRef(const Metadata *V) : Val(V) {
666 assert(isDescriptorRef(V) &&
667 "DIDescriptorRef should be a MDString or MDNode");
669 template <> DIRef<DIScope>::DIRef(const Metadata *V) : Val(V) {
670 assert(isScopeRef(V) && "DIScopeRef should be a MDString or MDNode");
672 template <> DIRef<DIType>::DIRef(const Metadata *V) : Val(V) {
673 assert(isTypeRef(V) && "DITypeRef should be a MDString or MDNode");
677 DIDescriptorRef DIDescriptor::getFieldAs<DIDescriptorRef>(unsigned Elt) const {
678 return DIDescriptorRef(cast_or_null<Metadata>(getField(DbgNode, Elt)));
681 DIScopeRef DIDescriptor::getFieldAs<DIScopeRef>(unsigned Elt) const {
682 return DIScopeRef(cast_or_null<Metadata>(getField(DbgNode, Elt)));
684 template <> DITypeRef DIDescriptor::getFieldAs<DITypeRef>(unsigned Elt) const {
685 return DITypeRef(cast_or_null<Metadata>(getField(DbgNode, Elt)));
690 DIRef<DIDescriptor>::resolve(const DITypeIdentifierMap &Map) const {
691 return DIDescriptor(DebugNodeRef(Val).resolve(Map));
694 DIScope DIRef<DIScope>::resolve(const DITypeIdentifierMap &Map) const {
695 return MDScopeRef(Val).resolve(Map);
698 DIType DIRef<DIType>::resolve(const DITypeIdentifierMap &Map) const {
699 return MDTypeRef(Val).resolve(Map);
702 bool llvm::stripDebugInfo(Function &F) {
703 bool Changed = false;
704 for (BasicBlock &BB : F) {
705 for (Instruction &I : BB) {
706 if (I.getDebugLoc()) {
708 I.setDebugLoc(DebugLoc());
715 bool llvm::StripDebugInfo(Module &M) {
716 bool Changed = false;
718 // Remove all of the calls to the debugger intrinsics, and remove them from
720 if (Function *Declare = M.getFunction("llvm.dbg.declare")) {
721 while (!Declare->use_empty()) {
722 CallInst *CI = cast<CallInst>(Declare->user_back());
723 CI->eraseFromParent();
725 Declare->eraseFromParent();
729 if (Function *DbgVal = M.getFunction("llvm.dbg.value")) {
730 while (!DbgVal->use_empty()) {
731 CallInst *CI = cast<CallInst>(DbgVal->user_back());
732 CI->eraseFromParent();
734 DbgVal->eraseFromParent();
738 for (Module::named_metadata_iterator NMI = M.named_metadata_begin(),
739 NME = M.named_metadata_end(); NMI != NME;) {
740 NamedMDNode *NMD = NMI;
742 if (NMD->getName().startswith("llvm.dbg.")) {
743 NMD->eraseFromParent();
748 for (Function &F : M)
749 Changed |= stripDebugInfo(F);
751 if (GVMaterializer *Materializer = M.getMaterializer())
752 Materializer->setStripDebugInfo();
757 unsigned llvm::getDebugMetadataVersionFromModule(const Module &M) {
758 if (auto *Val = mdconst::dyn_extract_or_null<ConstantInt>(
759 M.getModuleFlag("Debug Info Version")))
760 return Val->getZExtValue();
764 llvm::DenseMap<const llvm::Function *, llvm::DISubprogram>
765 llvm::makeSubprogramMap(const Module &M) {
766 DenseMap<const Function *, DISubprogram> R;
768 NamedMDNode *CU_Nodes = M.getNamedMetadata("llvm.dbg.cu");
772 for (MDNode *N : CU_Nodes->operands()) {
773 DICompileUnit CUNode(N);
774 DIArray SPs = CUNode.getSubprograms();
775 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) {
776 DISubprogram SP(SPs.getElement(i));
777 if (Function *F = SP.getFunction())
778 R.insert(std::make_pair(F, SP));