1 //===- Metadata.cpp - Implement Metadata classes --------------------------===//
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
9 // This file implements the Metadata classes.
11 //===----------------------------------------------------------------------===//
13 #include "LLVMContextImpl.h"
14 #include "MetadataImpl.h"
15 #include "SymbolTableListTraitsImpl.h"
16 #include "llvm/ADT/APFloat.h"
17 #include "llvm/ADT/APInt.h"
18 #include "llvm/ADT/ArrayRef.h"
19 #include "llvm/ADT/DenseSet.h"
20 #include "llvm/ADT/None.h"
21 #include "llvm/ADT/STLExtras.h"
22 #include "llvm/ADT/SetVector.h"
23 #include "llvm/ADT/SmallPtrSet.h"
24 #include "llvm/ADT/SmallSet.h"
25 #include "llvm/ADT/SmallVector.h"
26 #include "llvm/ADT/StringMap.h"
27 #include "llvm/ADT/StringRef.h"
28 #include "llvm/ADT/Twine.h"
29 #include "llvm/IR/Argument.h"
30 #include "llvm/IR/BasicBlock.h"
31 #include "llvm/IR/Constant.h"
32 #include "llvm/IR/ConstantRange.h"
33 #include "llvm/IR/Constants.h"
34 #include "llvm/IR/DebugInfoMetadata.h"
35 #include "llvm/IR/DebugLoc.h"
36 #include "llvm/IR/Function.h"
37 #include "llvm/IR/GlobalObject.h"
38 #include "llvm/IR/GlobalVariable.h"
39 #include "llvm/IR/Instruction.h"
40 #include "llvm/IR/LLVMContext.h"
41 #include "llvm/IR/Metadata.h"
42 #include "llvm/IR/Module.h"
43 #include "llvm/IR/TrackingMDRef.h"
44 #include "llvm/IR/Type.h"
45 #include "llvm/IR/Value.h"
46 #include "llvm/IR/ValueHandle.h"
47 #include "llvm/Support/Casting.h"
48 #include "llvm/Support/ErrorHandling.h"
49 #include "llvm/Support/MathExtras.h"
56 #include <type_traits>
62 MetadataAsValue::MetadataAsValue(Type *Ty, Metadata *MD)
63 : Value(Ty, MetadataAsValueVal), MD(MD) {
67 MetadataAsValue::~MetadataAsValue() {
68 getType()->getContext().pImpl->MetadataAsValues.erase(MD);
72 /// Canonicalize metadata arguments to intrinsics.
74 /// To support bitcode upgrades (and assembly semantic sugar) for \a
75 /// MetadataAsValue, we need to canonicalize certain metadata.
77 /// - nullptr is replaced by an empty MDNode.
78 /// - An MDNode with a single null operand is replaced by an empty MDNode.
79 /// - An MDNode whose only operand is a \a ConstantAsMetadata gets skipped.
81 /// This maintains readability of bitcode from when metadata was a type of
82 /// value, and these bridges were unnecessary.
83 static Metadata *canonicalizeMetadataForValue(LLVMContext &Context,
87 return MDNode::get(Context, None);
89 // Return early if this isn't a single-operand MDNode.
90 auto *N = dyn_cast<MDNode>(MD);
91 if (!N || N->getNumOperands() != 1)
94 if (!N->getOperand(0))
96 return MDNode::get(Context, None);
98 if (auto *C = dyn_cast<ConstantAsMetadata>(N->getOperand(0)))
99 // Look through the MDNode.
105 MetadataAsValue *MetadataAsValue::get(LLVMContext &Context, Metadata *MD) {
106 MD = canonicalizeMetadataForValue(Context, MD);
107 auto *&Entry = Context.pImpl->MetadataAsValues[MD];
109 Entry = new MetadataAsValue(Type::getMetadataTy(Context), MD);
113 MetadataAsValue *MetadataAsValue::getIfExists(LLVMContext &Context,
115 MD = canonicalizeMetadataForValue(Context, MD);
116 auto &Store = Context.pImpl->MetadataAsValues;
117 return Store.lookup(MD);
120 void MetadataAsValue::handleChangedMetadata(Metadata *MD) {
121 LLVMContext &Context = getContext();
122 MD = canonicalizeMetadataForValue(Context, MD);
123 auto &Store = Context.pImpl->MetadataAsValues;
125 // Stop tracking the old metadata.
126 Store.erase(this->MD);
130 // Start tracking MD, or RAUW if necessary.
131 auto *&Entry = Store[MD];
133 replaceAllUsesWith(Entry);
143 void MetadataAsValue::track() {
145 MetadataTracking::track(&MD, *MD, *this);
148 void MetadataAsValue::untrack() {
150 MetadataTracking::untrack(MD);
153 bool MetadataTracking::track(void *Ref, Metadata &MD, OwnerTy Owner) {
154 assert(Ref && "Expected live reference");
155 assert((Owner || *static_cast<Metadata **>(Ref) == &MD) &&
156 "Reference without owner must be direct");
157 if (auto *R = ReplaceableMetadataImpl::getOrCreate(MD)) {
158 R->addRef(Ref, Owner);
161 if (auto *PH = dyn_cast<DistinctMDOperandPlaceholder>(&MD)) {
162 assert(!PH->Use && "Placeholders can only be used once");
163 assert(!Owner && "Unexpected callback to owner");
164 PH->Use = static_cast<Metadata **>(Ref);
170 void MetadataTracking::untrack(void *Ref, Metadata &MD) {
171 assert(Ref && "Expected live reference");
172 if (auto *R = ReplaceableMetadataImpl::getIfExists(MD))
174 else if (auto *PH = dyn_cast<DistinctMDOperandPlaceholder>(&MD))
178 bool MetadataTracking::retrack(void *Ref, Metadata &MD, void *New) {
179 assert(Ref && "Expected live reference");
180 assert(New && "Expected live reference");
181 assert(Ref != New && "Expected change");
182 if (auto *R = ReplaceableMetadataImpl::getIfExists(MD)) {
183 R->moveRef(Ref, New, MD);
186 assert(!isa<DistinctMDOperandPlaceholder>(MD) &&
187 "Unexpected move of an MDOperand");
188 assert(!isReplaceable(MD) &&
189 "Expected un-replaceable metadata, since we didn't move a reference");
193 bool MetadataTracking::isReplaceable(const Metadata &MD) {
194 return ReplaceableMetadataImpl::isReplaceable(MD);
197 void ReplaceableMetadataImpl::addRef(void *Ref, OwnerTy Owner) {
199 UseMap.insert(std::make_pair(Ref, std::make_pair(Owner, NextIndex)))
202 assert(WasInserted && "Expected to add a reference");
205 assert(NextIndex != 0 && "Unexpected overflow");
208 void ReplaceableMetadataImpl::dropRef(void *Ref) {
209 bool WasErased = UseMap.erase(Ref);
211 assert(WasErased && "Expected to drop a reference");
214 void ReplaceableMetadataImpl::moveRef(void *Ref, void *New,
215 const Metadata &MD) {
216 auto I = UseMap.find(Ref);
217 assert(I != UseMap.end() && "Expected to move a reference");
218 auto OwnerAndIndex = I->second;
220 bool WasInserted = UseMap.insert(std::make_pair(New, OwnerAndIndex)).second;
222 assert(WasInserted && "Expected to add a reference");
224 // Check that the references are direct if there's no owner.
226 assert((OwnerAndIndex.first || *static_cast<Metadata **>(Ref) == &MD) &&
227 "Reference without owner must be direct");
228 assert((OwnerAndIndex.first || *static_cast<Metadata **>(New) == &MD) &&
229 "Reference without owner must be direct");
232 void ReplaceableMetadataImpl::replaceAllUsesWith(Metadata *MD) {
236 // Copy out uses since UseMap will get touched below.
237 using UseTy = std::pair<void *, std::pair<OwnerTy, uint64_t>>;
238 SmallVector<UseTy, 8> Uses(UseMap.begin(), UseMap.end());
239 llvm::sort(Uses, [](const UseTy &L, const UseTy &R) {
240 return L.second.second < R.second.second;
242 for (const auto &Pair : Uses) {
243 // Check that this Ref hasn't disappeared after RAUW (when updating a
245 if (!UseMap.count(Pair.first))
248 OwnerTy Owner = Pair.second.first;
250 // Update unowned tracking references directly.
251 Metadata *&Ref = *static_cast<Metadata **>(Pair.first);
254 MetadataTracking::track(Ref);
255 UseMap.erase(Pair.first);
259 // Check for MetadataAsValue.
260 if (Owner.is<MetadataAsValue *>()) {
261 Owner.get<MetadataAsValue *>()->handleChangedMetadata(MD);
265 // There's a Metadata owner -- dispatch.
266 Metadata *OwnerMD = Owner.get<Metadata *>();
267 switch (OwnerMD->getMetadataID()) {
268 #define HANDLE_METADATA_LEAF(CLASS) \
269 case Metadata::CLASS##Kind: \
270 cast<CLASS>(OwnerMD)->handleChangedOperand(Pair.first, MD); \
272 #include "llvm/IR/Metadata.def"
274 llvm_unreachable("Invalid metadata subclass");
277 assert(UseMap.empty() && "Expected all uses to be replaced");
280 void ReplaceableMetadataImpl::resolveAllUses(bool ResolveUsers) {
289 // Copy out uses since UseMap could get touched below.
290 using UseTy = std::pair<void *, std::pair<OwnerTy, uint64_t>>;
291 SmallVector<UseTy, 8> Uses(UseMap.begin(), UseMap.end());
292 llvm::sort(Uses, [](const UseTy &L, const UseTy &R) {
293 return L.second.second < R.second.second;
296 for (const auto &Pair : Uses) {
297 auto Owner = Pair.second.first;
300 if (Owner.is<MetadataAsValue *>())
303 // Resolve MDNodes that point at this.
304 auto *OwnerMD = dyn_cast<MDNode>(Owner.get<Metadata *>());
307 if (OwnerMD->isResolved())
309 OwnerMD->decrementUnresolvedOperandCount();
313 ReplaceableMetadataImpl *ReplaceableMetadataImpl::getOrCreate(Metadata &MD) {
314 if (auto *N = dyn_cast<MDNode>(&MD))
315 return N->isResolved() ? nullptr : N->Context.getOrCreateReplaceableUses();
316 return dyn_cast<ValueAsMetadata>(&MD);
319 ReplaceableMetadataImpl *ReplaceableMetadataImpl::getIfExists(Metadata &MD) {
320 if (auto *N = dyn_cast<MDNode>(&MD))
321 return N->isResolved() ? nullptr : N->Context.getReplaceableUses();
322 return dyn_cast<ValueAsMetadata>(&MD);
325 bool ReplaceableMetadataImpl::isReplaceable(const Metadata &MD) {
326 if (auto *N = dyn_cast<MDNode>(&MD))
327 return !N->isResolved();
328 return dyn_cast<ValueAsMetadata>(&MD);
331 static DISubprogram *getLocalFunctionMetadata(Value *V) {
332 assert(V && "Expected value");
333 if (auto *A = dyn_cast<Argument>(V)) {
334 if (auto *Fn = A->getParent())
335 return Fn->getSubprogram();
339 if (BasicBlock *BB = cast<Instruction>(V)->getParent()) {
340 if (auto *Fn = BB->getParent())
341 return Fn->getSubprogram();
348 ValueAsMetadata *ValueAsMetadata::get(Value *V) {
349 assert(V && "Unexpected null Value");
351 auto &Context = V->getContext();
352 auto *&Entry = Context.pImpl->ValuesAsMetadata[V];
354 assert((isa<Constant>(V) || isa<Argument>(V) || isa<Instruction>(V)) &&
355 "Expected constant or function-local value");
356 assert(!V->IsUsedByMD && "Expected this to be the only metadata use");
357 V->IsUsedByMD = true;
358 if (auto *C = dyn_cast<Constant>(V))
359 Entry = new ConstantAsMetadata(C);
361 Entry = new LocalAsMetadata(V);
367 ValueAsMetadata *ValueAsMetadata::getIfExists(Value *V) {
368 assert(V && "Unexpected null Value");
369 return V->getContext().pImpl->ValuesAsMetadata.lookup(V);
372 void ValueAsMetadata::handleDeletion(Value *V) {
373 assert(V && "Expected valid value");
375 auto &Store = V->getType()->getContext().pImpl->ValuesAsMetadata;
376 auto I = Store.find(V);
377 if (I == Store.end())
380 // Remove old entry from the map.
381 ValueAsMetadata *MD = I->second;
382 assert(MD && "Expected valid metadata");
383 assert(MD->getValue() == V && "Expected valid mapping");
386 // Delete the metadata.
387 MD->replaceAllUsesWith(nullptr);
391 void ValueAsMetadata::handleRAUW(Value *From, Value *To) {
392 assert(From && "Expected valid value");
393 assert(To && "Expected valid value");
394 assert(From != To && "Expected changed value");
395 assert(From->getType() == To->getType() && "Unexpected type change");
397 LLVMContext &Context = From->getType()->getContext();
398 auto &Store = Context.pImpl->ValuesAsMetadata;
399 auto I = Store.find(From);
400 if (I == Store.end()) {
401 assert(!From->IsUsedByMD && "Expected From not to be used by metadata");
405 // Remove old entry from the map.
406 assert(From->IsUsedByMD && "Expected From to be used by metadata");
407 From->IsUsedByMD = false;
408 ValueAsMetadata *MD = I->second;
409 assert(MD && "Expected valid metadata");
410 assert(MD->getValue() == From && "Expected valid mapping");
413 if (isa<LocalAsMetadata>(MD)) {
414 if (auto *C = dyn_cast<Constant>(To)) {
415 // Local became a constant.
416 MD->replaceAllUsesWith(ConstantAsMetadata::get(C));
420 if (getLocalFunctionMetadata(From) && getLocalFunctionMetadata(To) &&
421 getLocalFunctionMetadata(From) != getLocalFunctionMetadata(To)) {
422 // DISubprogram changed.
423 MD->replaceAllUsesWith(nullptr);
427 } else if (!isa<Constant>(To)) {
428 // Changed to function-local value.
429 MD->replaceAllUsesWith(nullptr);
434 auto *&Entry = Store[To];
436 // The target already exists.
437 MD->replaceAllUsesWith(Entry);
442 // Update MD in place (and update the map entry).
443 assert(!To->IsUsedByMD && "Expected this to be the only metadata use");
444 To->IsUsedByMD = true;
449 //===----------------------------------------------------------------------===//
450 // MDString implementation.
453 MDString *MDString::get(LLVMContext &Context, StringRef Str) {
454 auto &Store = Context.pImpl->MDStringCache;
455 auto I = Store.try_emplace(Str);
456 auto &MapEntry = I.first->getValue();
459 MapEntry.Entry = &*I.first;
463 StringRef MDString::getString() const {
464 assert(Entry && "Expected to find string map entry");
465 return Entry->first();
468 //===----------------------------------------------------------------------===//
469 // MDNode implementation.
472 // Assert that the MDNode types will not be unaligned by the objects
473 // prepended to them.
474 #define HANDLE_MDNODE_LEAF(CLASS) \
476 alignof(uint64_t) >= alignof(CLASS), \
477 "Alignment is insufficient after objects prepended to " #CLASS);
478 #include "llvm/IR/Metadata.def"
480 void *MDNode::operator new(size_t Size, unsigned NumOps) {
481 size_t OpSize = NumOps * sizeof(MDOperand);
482 // uint64_t is the most aligned type we need support (ensured by static_assert
484 OpSize = alignTo(OpSize, alignof(uint64_t));
485 void *Ptr = reinterpret_cast<char *>(::operator new(OpSize + Size)) + OpSize;
486 MDOperand *O = static_cast<MDOperand *>(Ptr);
487 for (MDOperand *E = O - NumOps; O != E; --O)
488 (void)new (O - 1) MDOperand;
492 void MDNode::operator delete(void *Mem) {
493 MDNode *N = static_cast<MDNode *>(Mem);
494 size_t OpSize = N->NumOperands * sizeof(MDOperand);
495 OpSize = alignTo(OpSize, alignof(uint64_t));
497 MDOperand *O = static_cast<MDOperand *>(Mem);
498 for (MDOperand *E = O - N->NumOperands; O != E; --O)
499 (O - 1)->~MDOperand();
500 ::operator delete(reinterpret_cast<char *>(Mem) - OpSize);
503 MDNode::MDNode(LLVMContext &Context, unsigned ID, StorageType Storage,
504 ArrayRef<Metadata *> Ops1, ArrayRef<Metadata *> Ops2)
505 : Metadata(ID, Storage), NumOperands(Ops1.size() + Ops2.size()),
506 NumUnresolved(0), Context(Context) {
508 for (Metadata *MD : Ops1)
509 setOperand(Op++, MD);
510 for (Metadata *MD : Ops2)
511 setOperand(Op++, MD);
516 // Count the unresolved operands. If there are any, RAUW support will be
517 // added lazily on first reference.
518 countUnresolvedOperands();
521 TempMDNode MDNode::clone() const {
522 switch (getMetadataID()) {
524 llvm_unreachable("Invalid MDNode subclass");
525 #define HANDLE_MDNODE_LEAF(CLASS) \
527 return cast<CLASS>(this)->cloneImpl();
528 #include "llvm/IR/Metadata.def"
532 static bool isOperandUnresolved(Metadata *Op) {
533 if (auto *N = dyn_cast_or_null<MDNode>(Op))
534 return !N->isResolved();
538 void MDNode::countUnresolvedOperands() {
539 assert(NumUnresolved == 0 && "Expected unresolved ops to be uncounted");
540 assert(isUniqued() && "Expected this to be uniqued");
541 NumUnresolved = count_if(operands(), isOperandUnresolved);
544 void MDNode::makeUniqued() {
545 assert(isTemporary() && "Expected this to be temporary");
546 assert(!isResolved() && "Expected this to be unresolved");
548 // Enable uniquing callbacks.
549 for (auto &Op : mutable_operands())
550 Op.reset(Op.get(), this);
552 // Make this 'uniqued'.
554 countUnresolvedOperands();
555 if (!NumUnresolved) {
556 dropReplaceableUses();
557 assert(isResolved() && "Expected this to be resolved");
560 assert(isUniqued() && "Expected this to be uniqued");
563 void MDNode::makeDistinct() {
564 assert(isTemporary() && "Expected this to be temporary");
565 assert(!isResolved() && "Expected this to be unresolved");
567 // Drop RAUW support and store as a distinct node.
568 dropReplaceableUses();
569 storeDistinctInContext();
571 assert(isDistinct() && "Expected this to be distinct");
572 assert(isResolved() && "Expected this to be resolved");
575 void MDNode::resolve() {
576 assert(isUniqued() && "Expected this to be uniqued");
577 assert(!isResolved() && "Expected this to be unresolved");
580 dropReplaceableUses();
582 assert(isResolved() && "Expected this to be resolved");
585 void MDNode::dropReplaceableUses() {
586 assert(!NumUnresolved && "Unexpected unresolved operand");
588 // Drop any RAUW support.
589 if (Context.hasReplaceableUses())
590 Context.takeReplaceableUses()->resolveAllUses();
593 void MDNode::resolveAfterOperandChange(Metadata *Old, Metadata *New) {
594 assert(isUniqued() && "Expected this to be uniqued");
595 assert(NumUnresolved != 0 && "Expected unresolved operands");
597 // Check if an operand was resolved.
598 if (!isOperandUnresolved(Old)) {
599 if (isOperandUnresolved(New))
600 // An operand was un-resolved!
602 } else if (!isOperandUnresolved(New))
603 decrementUnresolvedOperandCount();
606 void MDNode::decrementUnresolvedOperandCount() {
607 assert(!isResolved() && "Expected this to be unresolved");
611 assert(isUniqued() && "Expected this to be uniqued");
615 // Last unresolved operand has just been resolved.
616 dropReplaceableUses();
617 assert(isResolved() && "Expected this to become resolved");
620 void MDNode::resolveCycles() {
624 // Resolve this node immediately.
627 // Resolve all operands.
628 for (const auto &Op : operands()) {
629 auto *N = dyn_cast_or_null<MDNode>(Op);
633 assert(!N->isTemporary() &&
634 "Expected all forward declarations to be resolved");
635 if (!N->isResolved())
640 static bool hasSelfReference(MDNode *N) {
641 for (Metadata *MD : N->operands())
647 MDNode *MDNode::replaceWithPermanentImpl() {
648 switch (getMetadataID()) {
650 // If this type isn't uniquable, replace with a distinct node.
651 return replaceWithDistinctImpl();
653 #define HANDLE_MDNODE_LEAF_UNIQUABLE(CLASS) \
656 #include "llvm/IR/Metadata.def"
659 // Even if this type is uniquable, self-references have to be distinct.
660 if (hasSelfReference(this))
661 return replaceWithDistinctImpl();
662 return replaceWithUniquedImpl();
665 MDNode *MDNode::replaceWithUniquedImpl() {
666 // Try to uniquify in place.
667 MDNode *UniquedNode = uniquify();
669 if (UniquedNode == this) {
674 // Collision, so RAUW instead.
675 replaceAllUsesWith(UniquedNode);
680 MDNode *MDNode::replaceWithDistinctImpl() {
685 void MDTuple::recalculateHash() {
686 setHash(MDTupleInfo::KeyTy::calculateHash(this));
689 void MDNode::dropAllReferences() {
690 for (unsigned I = 0, E = NumOperands; I != E; ++I)
691 setOperand(I, nullptr);
692 if (Context.hasReplaceableUses()) {
693 Context.getReplaceableUses()->resolveAllUses(/* ResolveUsers */ false);
694 (void)Context.takeReplaceableUses();
698 void MDNode::handleChangedOperand(void *Ref, Metadata *New) {
699 unsigned Op = static_cast<MDOperand *>(Ref) - op_begin();
700 assert(Op < getNumOperands() && "Expected valid operand");
703 // This node is not uniqued. Just set the operand and be done with it.
708 // This node is uniqued.
711 Metadata *Old = getOperand(Op);
714 // Drop uniquing for self-reference cycles and deleted constants.
715 if (New == this || (!New && Old && isa<ConstantAsMetadata>(Old))) {
718 storeDistinctInContext();
722 // Re-unique the node.
723 auto *Uniqued = uniquify();
724 if (Uniqued == this) {
726 resolveAfterOperandChange(Old, New);
732 // Still unresolved, so RAUW.
734 // First, clear out all operands to prevent any recursion (similar to
735 // dropAllReferences(), but we still need the use-list).
736 for (unsigned O = 0, E = getNumOperands(); O != E; ++O)
737 setOperand(O, nullptr);
738 if (Context.hasReplaceableUses())
739 Context.getReplaceableUses()->replaceAllUsesWith(Uniqued);
744 // Store in non-uniqued form if RAUW isn't possible.
745 storeDistinctInContext();
748 void MDNode::deleteAsSubclass() {
749 switch (getMetadataID()) {
751 llvm_unreachable("Invalid subclass of MDNode");
752 #define HANDLE_MDNODE_LEAF(CLASS) \
754 delete cast<CLASS>(this); \
756 #include "llvm/IR/Metadata.def"
760 template <class T, class InfoT>
761 static T *uniquifyImpl(T *N, DenseSet<T *, InfoT> &Store) {
762 if (T *U = getUniqued(Store, N))
769 template <class NodeTy> struct MDNode::HasCachedHash {
772 template <class U, U Val> struct SFINAE {};
775 static Yes &check(SFINAE<void (U::*)(unsigned), &U::setHash> *);
776 template <class U> static No &check(...);
778 static const bool value = sizeof(check<NodeTy>(nullptr)) == sizeof(Yes);
781 MDNode *MDNode::uniquify() {
782 assert(!hasSelfReference(this) && "Cannot uniquify a self-referencing node");
784 // Try to insert into uniquing store.
785 switch (getMetadataID()) {
787 llvm_unreachable("Invalid or non-uniquable subclass of MDNode");
788 #define HANDLE_MDNODE_LEAF_UNIQUABLE(CLASS) \
789 case CLASS##Kind: { \
790 CLASS *SubclassThis = cast<CLASS>(this); \
791 std::integral_constant<bool, HasCachedHash<CLASS>::value> \
792 ShouldRecalculateHash; \
793 dispatchRecalculateHash(SubclassThis, ShouldRecalculateHash); \
794 return uniquifyImpl(SubclassThis, getContext().pImpl->CLASS##s); \
796 #include "llvm/IR/Metadata.def"
800 void MDNode::eraseFromStore() {
801 switch (getMetadataID()) {
803 llvm_unreachable("Invalid or non-uniquable subclass of MDNode");
804 #define HANDLE_MDNODE_LEAF_UNIQUABLE(CLASS) \
806 getContext().pImpl->CLASS##s.erase(cast<CLASS>(this)); \
808 #include "llvm/IR/Metadata.def"
812 MDTuple *MDTuple::getImpl(LLVMContext &Context, ArrayRef<Metadata *> MDs,
813 StorageType Storage, bool ShouldCreate) {
815 if (Storage == Uniqued) {
816 MDTupleInfo::KeyTy Key(MDs);
817 if (auto *N = getUniqued(Context.pImpl->MDTuples, Key))
821 Hash = Key.getHash();
823 assert(ShouldCreate && "Expected non-uniqued nodes to always be created");
826 return storeImpl(new (MDs.size()) MDTuple(Context, Storage, Hash, MDs),
827 Storage, Context.pImpl->MDTuples);
830 void MDNode::deleteTemporary(MDNode *N) {
831 assert(N->isTemporary() && "Expected temporary node");
832 N->replaceAllUsesWith(nullptr);
833 N->deleteAsSubclass();
836 void MDNode::storeDistinctInContext() {
837 assert(!Context.hasReplaceableUses() && "Unexpected replaceable uses");
838 assert(!NumUnresolved && "Unexpected unresolved nodes");
840 assert(isResolved() && "Expected this to be resolved");
843 switch (getMetadataID()) {
845 llvm_unreachable("Invalid subclass of MDNode");
846 #define HANDLE_MDNODE_LEAF(CLASS) \
847 case CLASS##Kind: { \
848 std::integral_constant<bool, HasCachedHash<CLASS>::value> ShouldResetHash; \
849 dispatchResetHash(cast<CLASS>(this), ShouldResetHash); \
852 #include "llvm/IR/Metadata.def"
855 getContext().pImpl->DistinctMDNodes.push_back(this);
858 void MDNode::replaceOperandWith(unsigned I, Metadata *New) {
859 if (getOperand(I) == New)
867 handleChangedOperand(mutable_begin() + I, New);
870 void MDNode::setOperand(unsigned I, Metadata *New) {
871 assert(I < NumOperands);
872 mutable_begin()[I].reset(New, isUniqued() ? this : nullptr);
875 /// Get a node or a self-reference that looks like it.
877 /// Special handling for finding self-references, for use by \a
878 /// MDNode::concatenate() and \a MDNode::intersect() to maintain behaviour from
879 /// when self-referencing nodes were still uniqued. If the first operand has
880 /// the same operands as \c Ops, return the first operand instead.
881 static MDNode *getOrSelfReference(LLVMContext &Context,
882 ArrayRef<Metadata *> Ops) {
884 if (MDNode *N = dyn_cast_or_null<MDNode>(Ops[0]))
885 if (N->getNumOperands() == Ops.size() && N == N->getOperand(0)) {
886 for (unsigned I = 1, E = Ops.size(); I != E; ++I)
887 if (Ops[I] != N->getOperand(I))
888 return MDNode::get(Context, Ops);
892 return MDNode::get(Context, Ops);
895 MDNode *MDNode::concatenate(MDNode *A, MDNode *B) {
901 SmallSetVector<Metadata *, 4> MDs(A->op_begin(), A->op_end());
902 MDs.insert(B->op_begin(), B->op_end());
904 // FIXME: This preserves long-standing behaviour, but is it really the right
905 // behaviour? Or was that an unintended side-effect of node uniquing?
906 return getOrSelfReference(A->getContext(), MDs.getArrayRef());
909 MDNode *MDNode::intersect(MDNode *A, MDNode *B) {
913 SmallSetVector<Metadata *, 4> MDs(A->op_begin(), A->op_end());
914 SmallPtrSet<Metadata *, 4> BSet(B->op_begin(), B->op_end());
915 MDs.remove_if([&](Metadata *MD) { return !is_contained(BSet, MD); });
917 // FIXME: This preserves long-standing behaviour, but is it really the right
918 // behaviour? Or was that an unintended side-effect of node uniquing?
919 return getOrSelfReference(A->getContext(), MDs.getArrayRef());
922 MDNode *MDNode::getMostGenericAliasScope(MDNode *A, MDNode *B) {
926 return concatenate(A, B);
929 MDNode *MDNode::getMostGenericFPMath(MDNode *A, MDNode *B) {
933 APFloat AVal = mdconst::extract<ConstantFP>(A->getOperand(0))->getValueAPF();
934 APFloat BVal = mdconst::extract<ConstantFP>(B->getOperand(0))->getValueAPF();
935 if (AVal.compare(BVal) == APFloat::cmpLessThan)
940 static bool isContiguous(const ConstantRange &A, const ConstantRange &B) {
941 return A.getUpper() == B.getLower() || A.getLower() == B.getUpper();
944 static bool canBeMerged(const ConstantRange &A, const ConstantRange &B) {
945 return !A.intersectWith(B).isEmptySet() || isContiguous(A, B);
948 static bool tryMergeRange(SmallVectorImpl<ConstantInt *> &EndPoints,
949 ConstantInt *Low, ConstantInt *High) {
950 ConstantRange NewRange(Low->getValue(), High->getValue());
951 unsigned Size = EndPoints.size();
952 APInt LB = EndPoints[Size - 2]->getValue();
953 APInt LE = EndPoints[Size - 1]->getValue();
954 ConstantRange LastRange(LB, LE);
955 if (canBeMerged(NewRange, LastRange)) {
956 ConstantRange Union = LastRange.unionWith(NewRange);
957 Type *Ty = High->getType();
958 EndPoints[Size - 2] =
959 cast<ConstantInt>(ConstantInt::get(Ty, Union.getLower()));
960 EndPoints[Size - 1] =
961 cast<ConstantInt>(ConstantInt::get(Ty, Union.getUpper()));
967 static void addRange(SmallVectorImpl<ConstantInt *> &EndPoints,
968 ConstantInt *Low, ConstantInt *High) {
969 if (!EndPoints.empty())
970 if (tryMergeRange(EndPoints, Low, High))
973 EndPoints.push_back(Low);
974 EndPoints.push_back(High);
977 MDNode *MDNode::getMostGenericRange(MDNode *A, MDNode *B) {
978 // Given two ranges, we want to compute the union of the ranges. This
979 // is slightly complicated by having to combine the intervals and merge
980 // the ones that overlap.
988 // First, walk both lists in order of the lower boundary of each interval.
989 // At each step, try to merge the new interval to the last one we adedd.
990 SmallVector<ConstantInt *, 4> EndPoints;
993 int AN = A->getNumOperands() / 2;
994 int BN = B->getNumOperands() / 2;
995 while (AI < AN && BI < BN) {
996 ConstantInt *ALow = mdconst::extract<ConstantInt>(A->getOperand(2 * AI));
997 ConstantInt *BLow = mdconst::extract<ConstantInt>(B->getOperand(2 * BI));
999 if (ALow->getValue().slt(BLow->getValue())) {
1000 addRange(EndPoints, ALow,
1001 mdconst::extract<ConstantInt>(A->getOperand(2 * AI + 1)));
1004 addRange(EndPoints, BLow,
1005 mdconst::extract<ConstantInt>(B->getOperand(2 * BI + 1)));
1010 addRange(EndPoints, mdconst::extract<ConstantInt>(A->getOperand(2 * AI)),
1011 mdconst::extract<ConstantInt>(A->getOperand(2 * AI + 1)));
1015 addRange(EndPoints, mdconst::extract<ConstantInt>(B->getOperand(2 * BI)),
1016 mdconst::extract<ConstantInt>(B->getOperand(2 * BI + 1)));
1020 // If we have more than 2 ranges (4 endpoints) we have to try to merge
1021 // the last and first ones.
1022 unsigned Size = EndPoints.size();
1024 ConstantInt *FB = EndPoints[0];
1025 ConstantInt *FE = EndPoints[1];
1026 if (tryMergeRange(EndPoints, FB, FE)) {
1027 for (unsigned i = 0; i < Size - 2; ++i) {
1028 EndPoints[i] = EndPoints[i + 2];
1030 EndPoints.resize(Size - 2);
1034 // If in the end we have a single range, it is possible that it is now the
1035 // full range. Just drop the metadata in that case.
1036 if (EndPoints.size() == 2) {
1037 ConstantRange Range(EndPoints[0]->getValue(), EndPoints[1]->getValue());
1038 if (Range.isFullSet())
1042 SmallVector<Metadata *, 4> MDs;
1043 MDs.reserve(EndPoints.size());
1044 for (auto *I : EndPoints)
1045 MDs.push_back(ConstantAsMetadata::get(I));
1046 return MDNode::get(A->getContext(), MDs);
1049 MDNode *MDNode::getMostGenericAlignmentOrDereferenceable(MDNode *A, MDNode *B) {
1053 ConstantInt *AVal = mdconst::extract<ConstantInt>(A->getOperand(0));
1054 ConstantInt *BVal = mdconst::extract<ConstantInt>(B->getOperand(0));
1055 if (AVal->getZExtValue() < BVal->getZExtValue())
1060 //===----------------------------------------------------------------------===//
1061 // NamedMDNode implementation.
1064 static SmallVector<TrackingMDRef, 4> &getNMDOps(void *Operands) {
1065 return *(SmallVector<TrackingMDRef, 4> *)Operands;
1068 NamedMDNode::NamedMDNode(const Twine &N)
1069 : Name(N.str()), Operands(new SmallVector<TrackingMDRef, 4>()) {}
1071 NamedMDNode::~NamedMDNode() {
1072 dropAllReferences();
1073 delete &getNMDOps(Operands);
1076 unsigned NamedMDNode::getNumOperands() const {
1077 return (unsigned)getNMDOps(Operands).size();
1080 MDNode *NamedMDNode::getOperand(unsigned i) const {
1081 assert(i < getNumOperands() && "Invalid Operand number!");
1082 auto *N = getNMDOps(Operands)[i].get();
1083 return cast_or_null<MDNode>(N);
1086 void NamedMDNode::addOperand(MDNode *M) { getNMDOps(Operands).emplace_back(M); }
1088 void NamedMDNode::setOperand(unsigned I, MDNode *New) {
1089 assert(I < getNumOperands() && "Invalid operand number");
1090 getNMDOps(Operands)[I].reset(New);
1093 void NamedMDNode::eraseFromParent() { getParent()->eraseNamedMetadata(this); }
1095 void NamedMDNode::clearOperands() { getNMDOps(Operands).clear(); }
1097 StringRef NamedMDNode::getName() const { return StringRef(Name); }
1099 //===----------------------------------------------------------------------===//
1100 // Instruction Metadata method implementations.
1102 void MDAttachmentMap::set(unsigned ID, MDNode &MD) {
1103 for (auto &I : Attachments)
1104 if (I.first == ID) {
1105 I.second.reset(&MD);
1108 Attachments.emplace_back(std::piecewise_construct, std::make_tuple(ID),
1109 std::make_tuple(&MD));
1112 bool MDAttachmentMap::erase(unsigned ID) {
1116 // Common case is one/last value.
1117 if (Attachments.back().first == ID) {
1118 Attachments.pop_back();
1122 for (auto I = Attachments.begin(), E = std::prev(Attachments.end()); I != E;
1124 if (I->first == ID) {
1125 *I = std::move(Attachments.back());
1126 Attachments.pop_back();
1133 MDNode *MDAttachmentMap::lookup(unsigned ID) const {
1134 for (const auto &I : Attachments)
1140 void MDAttachmentMap::getAll(
1141 SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
1142 Result.append(Attachments.begin(), Attachments.end());
1144 // Sort the resulting array so it is stable.
1145 if (Result.size() > 1)
1146 array_pod_sort(Result.begin(), Result.end());
1149 void MDGlobalAttachmentMap::insert(unsigned ID, MDNode &MD) {
1150 Attachments.push_back({ID, TrackingMDNodeRef(&MD)});
1153 MDNode *MDGlobalAttachmentMap::lookup(unsigned ID) const {
1154 for (const auto &A : Attachments)
1160 void MDGlobalAttachmentMap::get(unsigned ID,
1161 SmallVectorImpl<MDNode *> &Result) const {
1162 for (const auto &A : Attachments)
1164 Result.push_back(A.Node);
1167 bool MDGlobalAttachmentMap::erase(unsigned ID) {
1168 auto I = std::remove_if(Attachments.begin(), Attachments.end(),
1169 [ID](const Attachment &A) { return A.MDKind == ID; });
1170 bool Changed = I != Attachments.end();
1171 Attachments.erase(I, Attachments.end());
1175 void MDGlobalAttachmentMap::getAll(
1176 SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
1177 for (const auto &A : Attachments)
1178 Result.emplace_back(A.MDKind, A.Node);
1180 // Sort the resulting array so it is stable with respect to metadata IDs. We
1181 // need to preserve the original insertion order though.
1182 llvm::stable_sort(Result, less_first());
1185 void Instruction::setMetadata(StringRef Kind, MDNode *Node) {
1186 if (!Node && !hasMetadata())
1188 setMetadata(getContext().getMDKindID(Kind), Node);
1191 MDNode *Instruction::getMetadataImpl(StringRef Kind) const {
1192 return getMetadataImpl(getContext().getMDKindID(Kind));
1195 void Instruction::dropUnknownNonDebugMetadata(ArrayRef<unsigned> KnownIDs) {
1196 if (!hasMetadataHashEntry())
1197 return; // Nothing to remove!
1199 auto &InstructionMetadata = getContext().pImpl->InstructionMetadata;
1201 SmallSet<unsigned, 4> KnownSet;
1202 KnownSet.insert(KnownIDs.begin(), KnownIDs.end());
1203 if (KnownSet.empty()) {
1204 // Just drop our entry at the store.
1205 InstructionMetadata.erase(this);
1206 setHasMetadataHashEntry(false);
1210 auto &Info = InstructionMetadata[this];
1211 Info.remove_if([&KnownSet](const std::pair<unsigned, TrackingMDNodeRef> &I) {
1212 return !KnownSet.count(I.first);
1216 // Drop our entry at the store.
1217 InstructionMetadata.erase(this);
1218 setHasMetadataHashEntry(false);
1222 void Instruction::setMetadata(unsigned KindID, MDNode *Node) {
1223 if (!Node && !hasMetadata())
1226 // Handle 'dbg' as a special case since it is not stored in the hash table.
1227 if (KindID == LLVMContext::MD_dbg) {
1228 DbgLoc = DebugLoc(Node);
1232 // Handle the case when we're adding/updating metadata on an instruction.
1234 auto &Info = getContext().pImpl->InstructionMetadata[this];
1235 assert(!Info.empty() == hasMetadataHashEntry() &&
1236 "HasMetadata bit is wonked");
1238 setHasMetadataHashEntry(true);
1239 Info.set(KindID, *Node);
1243 // Otherwise, we're removing metadata from an instruction.
1244 assert((hasMetadataHashEntry() ==
1245 (getContext().pImpl->InstructionMetadata.count(this) > 0)) &&
1246 "HasMetadata bit out of date!");
1247 if (!hasMetadataHashEntry())
1248 return; // Nothing to remove!
1249 auto &Info = getContext().pImpl->InstructionMetadata[this];
1251 // Handle removal of an existing value.
1257 getContext().pImpl->InstructionMetadata.erase(this);
1258 setHasMetadataHashEntry(false);
1261 void Instruction::setAAMetadata(const AAMDNodes &N) {
1262 setMetadata(LLVMContext::MD_tbaa, N.TBAA);
1263 setMetadata(LLVMContext::MD_alias_scope, N.Scope);
1264 setMetadata(LLVMContext::MD_noalias, N.NoAlias);
1267 MDNode *Instruction::getMetadataImpl(unsigned KindID) const {
1268 // Handle 'dbg' as a special case since it is not stored in the hash table.
1269 if (KindID == LLVMContext::MD_dbg)
1270 return DbgLoc.getAsMDNode();
1272 if (!hasMetadataHashEntry())
1274 auto &Info = getContext().pImpl->InstructionMetadata[this];
1275 assert(!Info.empty() && "bit out of sync with hash table");
1277 return Info.lookup(KindID);
1280 void Instruction::getAllMetadataImpl(
1281 SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
1284 // Handle 'dbg' as a special case since it is not stored in the hash table.
1287 std::make_pair((unsigned)LLVMContext::MD_dbg, DbgLoc.getAsMDNode()));
1288 if (!hasMetadataHashEntry())
1292 assert(hasMetadataHashEntry() &&
1293 getContext().pImpl->InstructionMetadata.count(this) &&
1294 "Shouldn't have called this");
1295 const auto &Info = getContext().pImpl->InstructionMetadata.find(this)->second;
1296 assert(!Info.empty() && "Shouldn't have called this");
1297 Info.getAll(Result);
1300 void Instruction::getAllMetadataOtherThanDebugLocImpl(
1301 SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
1303 assert(hasMetadataHashEntry() &&
1304 getContext().pImpl->InstructionMetadata.count(this) &&
1305 "Shouldn't have called this");
1306 const auto &Info = getContext().pImpl->InstructionMetadata.find(this)->second;
1307 assert(!Info.empty() && "Shouldn't have called this");
1308 Info.getAll(Result);
1311 bool Instruction::extractProfMetadata(uint64_t &TrueVal,
1312 uint64_t &FalseVal) const {
1314 (getOpcode() == Instruction::Br || getOpcode() == Instruction::Select) &&
1315 "Looking for branch weights on something besides branch or select");
1317 auto *ProfileData = getMetadata(LLVMContext::MD_prof);
1318 if (!ProfileData || ProfileData->getNumOperands() != 3)
1321 auto *ProfDataName = dyn_cast<MDString>(ProfileData->getOperand(0));
1322 if (!ProfDataName || !ProfDataName->getString().equals("branch_weights"))
1325 auto *CITrue = mdconst::dyn_extract<ConstantInt>(ProfileData->getOperand(1));
1326 auto *CIFalse = mdconst::dyn_extract<ConstantInt>(ProfileData->getOperand(2));
1327 if (!CITrue || !CIFalse)
1330 TrueVal = CITrue->getValue().getZExtValue();
1331 FalseVal = CIFalse->getValue().getZExtValue();
1336 bool Instruction::extractProfTotalWeight(uint64_t &TotalVal) const {
1337 assert((getOpcode() == Instruction::Br ||
1338 getOpcode() == Instruction::Select ||
1339 getOpcode() == Instruction::Call ||
1340 getOpcode() == Instruction::Invoke ||
1341 getOpcode() == Instruction::Switch) &&
1342 "Looking for branch weights on something besides branch");
1345 auto *ProfileData = getMetadata(LLVMContext::MD_prof);
1349 auto *ProfDataName = dyn_cast<MDString>(ProfileData->getOperand(0));
1353 if (ProfDataName->getString().equals("branch_weights")) {
1355 for (unsigned i = 1; i < ProfileData->getNumOperands(); i++) {
1356 auto *V = mdconst::dyn_extract<ConstantInt>(ProfileData->getOperand(i));
1359 TotalVal += V->getValue().getZExtValue();
1362 } else if (ProfDataName->getString().equals("VP") &&
1363 ProfileData->getNumOperands() > 3) {
1364 TotalVal = mdconst::dyn_extract<ConstantInt>(ProfileData->getOperand(2))
1372 void Instruction::clearMetadataHashEntries() {
1373 assert(hasMetadataHashEntry() && "Caller should check");
1374 getContext().pImpl->InstructionMetadata.erase(this);
1375 setHasMetadataHashEntry(false);
1378 void GlobalObject::getMetadata(unsigned KindID,
1379 SmallVectorImpl<MDNode *> &MDs) const {
1381 getContext().pImpl->GlobalObjectMetadata[this].get(KindID, MDs);
1384 void GlobalObject::getMetadata(StringRef Kind,
1385 SmallVectorImpl<MDNode *> &MDs) const {
1387 getMetadata(getContext().getMDKindID(Kind), MDs);
1390 void GlobalObject::addMetadata(unsigned KindID, MDNode &MD) {
1392 setHasMetadataHashEntry(true);
1394 getContext().pImpl->GlobalObjectMetadata[this].insert(KindID, MD);
1397 void GlobalObject::addMetadata(StringRef Kind, MDNode &MD) {
1398 addMetadata(getContext().getMDKindID(Kind), MD);
1401 bool GlobalObject::eraseMetadata(unsigned KindID) {
1402 // Nothing to unset.
1406 auto &Store = getContext().pImpl->GlobalObjectMetadata[this];
1407 bool Changed = Store.erase(KindID);
1413 void GlobalObject::getAllMetadata(
1414 SmallVectorImpl<std::pair<unsigned, MDNode *>> &MDs) const {
1420 getContext().pImpl->GlobalObjectMetadata[this].getAll(MDs);
1423 void GlobalObject::clearMetadata() {
1426 getContext().pImpl->GlobalObjectMetadata.erase(this);
1427 setHasMetadataHashEntry(false);
1430 void GlobalObject::setMetadata(unsigned KindID, MDNode *N) {
1431 eraseMetadata(KindID);
1433 addMetadata(KindID, *N);
1436 void GlobalObject::setMetadata(StringRef Kind, MDNode *N) {
1437 setMetadata(getContext().getMDKindID(Kind), N);
1440 MDNode *GlobalObject::getMetadata(unsigned KindID) const {
1442 return getContext().pImpl->GlobalObjectMetadata[this].lookup(KindID);
1446 MDNode *GlobalObject::getMetadata(StringRef Kind) const {
1447 return getMetadata(getContext().getMDKindID(Kind));
1450 void GlobalObject::copyMetadata(const GlobalObject *Other, unsigned Offset) {
1451 SmallVector<std::pair<unsigned, MDNode *>, 8> MDs;
1452 Other->getAllMetadata(MDs);
1453 for (auto &MD : MDs) {
1454 // We need to adjust the type metadata offset.
1455 if (Offset != 0 && MD.first == LLVMContext::MD_type) {
1456 auto *OffsetConst = cast<ConstantInt>(
1457 cast<ConstantAsMetadata>(MD.second->getOperand(0))->getValue());
1458 Metadata *TypeId = MD.second->getOperand(1);
1459 auto *NewOffsetMD = ConstantAsMetadata::get(ConstantInt::get(
1460 OffsetConst->getType(), OffsetConst->getValue() + Offset));
1461 addMetadata(LLVMContext::MD_type,
1462 *MDNode::get(getContext(), {NewOffsetMD, TypeId}));
1465 // If an offset adjustment was specified we need to modify the DIExpression
1466 // to prepend the adjustment:
1467 // !DIExpression(DW_OP_plus, Offset, [original expr])
1468 auto *Attachment = MD.second;
1469 if (Offset != 0 && MD.first == LLVMContext::MD_dbg) {
1470 DIGlobalVariable *GV = dyn_cast<DIGlobalVariable>(Attachment);
1471 DIExpression *E = nullptr;
1473 auto *GVE = cast<DIGlobalVariableExpression>(Attachment);
1474 GV = GVE->getVariable();
1475 E = GVE->getExpression();
1477 ArrayRef<uint64_t> OrigElements;
1479 OrigElements = E->getElements();
1480 std::vector<uint64_t> Elements(OrigElements.size() + 2);
1481 Elements[0] = dwarf::DW_OP_plus_uconst;
1482 Elements[1] = Offset;
1483 llvm::copy(OrigElements, Elements.begin() + 2);
1484 E = DIExpression::get(getContext(), Elements);
1485 Attachment = DIGlobalVariableExpression::get(getContext(), GV, E);
1487 addMetadata(MD.first, *Attachment);
1491 void GlobalObject::addTypeMetadata(unsigned Offset, Metadata *TypeID) {
1493 LLVMContext::MD_type,
1494 *MDTuple::get(getContext(),
1495 {ConstantAsMetadata::get(ConstantInt::get(
1496 Type::getInt64Ty(getContext()), Offset)),
1500 void Function::setSubprogram(DISubprogram *SP) {
1501 setMetadata(LLVMContext::MD_dbg, SP);
1504 DISubprogram *Function::getSubprogram() const {
1505 return cast_or_null<DISubprogram>(getMetadata(LLVMContext::MD_dbg));
1508 bool Function::isDebugInfoForProfiling() const {
1509 if (DISubprogram *SP = getSubprogram()) {
1510 if (DICompileUnit *CU = SP->getUnit()) {
1511 return CU->getDebugInfoForProfiling();
1517 void GlobalVariable::addDebugInfo(DIGlobalVariableExpression *GV) {
1518 addMetadata(LLVMContext::MD_dbg, *GV);
1521 void GlobalVariable::getDebugInfo(
1522 SmallVectorImpl<DIGlobalVariableExpression *> &GVs) const {
1523 SmallVector<MDNode *, 1> MDs;
1524 getMetadata(LLVMContext::MD_dbg, MDs);
1525 for (MDNode *MD : MDs)
1526 GVs.push_back(cast<DIGlobalVariableExpression>(MD));