1 //===-- Metadata.cpp - Implement Metadata classes -------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the Metadata classes.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "llvm/IR/Metadata.h"
15 #include "LLVMContextImpl.h"
16 #include "SymbolTableListTraitsImpl.h"
17 #include "llvm/ADT/DenseMap.h"
18 #include "llvm/ADT/STLExtras.h"
19 #include "llvm/ADT/SmallSet.h"
20 #include "llvm/ADT/SmallString.h"
21 #include "llvm/ADT/StringMap.h"
22 #include "llvm/IR/ConstantRange.h"
23 #include "llvm/IR/Instruction.h"
24 #include "llvm/IR/LLVMContext.h"
25 #include "llvm/IR/Module.h"
26 #include "llvm/IR/ValueHandle.h"
27
28 using namespace llvm;
29
MetadataAsValue(Type * Ty,Metadata * MD)30 MetadataAsValue::MetadataAsValue(Type *Ty, Metadata *MD)
31 : Value(Ty, MetadataAsValueVal), MD(MD) {
32 track();
33 }
34
~MetadataAsValue()35 MetadataAsValue::~MetadataAsValue() {
36 getType()->getContext().pImpl->MetadataAsValues.erase(MD);
37 untrack();
38 }
39
40 /// \brief Canonicalize metadata arguments to intrinsics.
41 ///
42 /// To support bitcode upgrades (and assembly semantic sugar) for \a
43 /// MetadataAsValue, we need to canonicalize certain metadata.
44 ///
45 /// - nullptr is replaced by an empty MDNode.
46 /// - An MDNode with a single null operand is replaced by an empty MDNode.
47 /// - An MDNode whose only operand is a \a ConstantAsMetadata gets skipped.
48 ///
49 /// This maintains readability of bitcode from when metadata was a type of
50 /// value, and these bridges were unnecessary.
canonicalizeMetadataForValue(LLVMContext & Context,Metadata * MD)51 static Metadata *canonicalizeMetadataForValue(LLVMContext &Context,
52 Metadata *MD) {
53 if (!MD)
54 // !{}
55 return MDNode::get(Context, None);
56
57 // Return early if this isn't a single-operand MDNode.
58 auto *N = dyn_cast<MDNode>(MD);
59 if (!N || N->getNumOperands() != 1)
60 return MD;
61
62 if (!N->getOperand(0))
63 // !{}
64 return MDNode::get(Context, None);
65
66 if (auto *C = dyn_cast<ConstantAsMetadata>(N->getOperand(0)))
67 // Look through the MDNode.
68 return C;
69
70 return MD;
71 }
72
get(LLVMContext & Context,Metadata * MD)73 MetadataAsValue *MetadataAsValue::get(LLVMContext &Context, Metadata *MD) {
74 MD = canonicalizeMetadataForValue(Context, MD);
75 auto *&Entry = Context.pImpl->MetadataAsValues[MD];
76 if (!Entry)
77 Entry = new MetadataAsValue(Type::getMetadataTy(Context), MD);
78 return Entry;
79 }
80
getIfExists(LLVMContext & Context,Metadata * MD)81 MetadataAsValue *MetadataAsValue::getIfExists(LLVMContext &Context,
82 Metadata *MD) {
83 MD = canonicalizeMetadataForValue(Context, MD);
84 auto &Store = Context.pImpl->MetadataAsValues;
85 auto I = Store.find(MD);
86 return I == Store.end() ? nullptr : I->second;
87 }
88
handleChangedMetadata(Metadata * MD)89 void MetadataAsValue::handleChangedMetadata(Metadata *MD) {
90 LLVMContext &Context = getContext();
91 MD = canonicalizeMetadataForValue(Context, MD);
92 auto &Store = Context.pImpl->MetadataAsValues;
93
94 // Stop tracking the old metadata.
95 Store.erase(this->MD);
96 untrack();
97 this->MD = nullptr;
98
99 // Start tracking MD, or RAUW if necessary.
100 auto *&Entry = Store[MD];
101 if (Entry) {
102 replaceAllUsesWith(Entry);
103 delete this;
104 return;
105 }
106
107 this->MD = MD;
108 track();
109 Entry = this;
110 }
111
track()112 void MetadataAsValue::track() {
113 if (MD)
114 MetadataTracking::track(&MD, *MD, *this);
115 }
116
untrack()117 void MetadataAsValue::untrack() {
118 if (MD)
119 MetadataTracking::untrack(MD);
120 }
121
addRef(void * Ref,OwnerTy Owner)122 void ReplaceableMetadataImpl::addRef(void *Ref, OwnerTy Owner) {
123 bool WasInserted =
124 UseMap.insert(std::make_pair(Ref, std::make_pair(Owner, NextIndex)))
125 .second;
126 (void)WasInserted;
127 assert(WasInserted && "Expected to add a reference");
128
129 ++NextIndex;
130 assert(NextIndex != 0 && "Unexpected overflow");
131 }
132
dropRef(void * Ref)133 void ReplaceableMetadataImpl::dropRef(void *Ref) {
134 bool WasErased = UseMap.erase(Ref);
135 (void)WasErased;
136 assert(WasErased && "Expected to drop a reference");
137 }
138
moveRef(void * Ref,void * New,const Metadata & MD)139 void ReplaceableMetadataImpl::moveRef(void *Ref, void *New,
140 const Metadata &MD) {
141 auto I = UseMap.find(Ref);
142 assert(I != UseMap.end() && "Expected to move a reference");
143 auto OwnerAndIndex = I->second;
144 UseMap.erase(I);
145 bool WasInserted = UseMap.insert(std::make_pair(New, OwnerAndIndex)).second;
146 (void)WasInserted;
147 assert(WasInserted && "Expected to add a reference");
148
149 // Check that the references are direct if there's no owner.
150 (void)MD;
151 assert((OwnerAndIndex.first || *static_cast<Metadata **>(Ref) == &MD) &&
152 "Reference without owner must be direct");
153 assert((OwnerAndIndex.first || *static_cast<Metadata **>(New) == &MD) &&
154 "Reference without owner must be direct");
155 }
156
replaceAllUsesWith(Metadata * MD)157 void ReplaceableMetadataImpl::replaceAllUsesWith(Metadata *MD) {
158 assert(!(MD && isa<MDNodeFwdDecl>(MD)) && "Expected non-temp node");
159
160 if (UseMap.empty())
161 return;
162
163 // Copy out uses since UseMap will get touched below.
164 typedef std::pair<void *, std::pair<OwnerTy, uint64_t>> UseTy;
165 SmallVector<UseTy, 8> Uses(UseMap.begin(), UseMap.end());
166 std::sort(Uses.begin(), Uses.end(), [](const UseTy &L, const UseTy &R) {
167 return L.second.second < R.second.second;
168 });
169 for (const auto &Pair : Uses) {
170 // Check that this Ref hasn't disappeared after RAUW (when updating a
171 // previous Ref).
172 if (!UseMap.count(Pair.first))
173 continue;
174
175 OwnerTy Owner = Pair.second.first;
176 if (!Owner) {
177 // Update unowned tracking references directly.
178 Metadata *&Ref = *static_cast<Metadata **>(Pair.first);
179 Ref = MD;
180 if (MD)
181 MetadataTracking::track(Ref);
182 UseMap.erase(Pair.first);
183 continue;
184 }
185
186 // Check for MetadataAsValue.
187 if (Owner.is<MetadataAsValue *>()) {
188 Owner.get<MetadataAsValue *>()->handleChangedMetadata(MD);
189 continue;
190 }
191
192 // There's a Metadata owner -- dispatch.
193 Metadata *OwnerMD = Owner.get<Metadata *>();
194 switch (OwnerMD->getMetadataID()) {
195 #define HANDLE_METADATA_LEAF(CLASS) \
196 case Metadata::CLASS##Kind: \
197 cast<CLASS>(OwnerMD)->handleChangedOperand(Pair.first, MD); \
198 continue;
199 #include "llvm/IR/Metadata.def"
200 default:
201 llvm_unreachable("Invalid metadata subclass");
202 }
203 }
204 assert(UseMap.empty() && "Expected all uses to be replaced");
205 }
206
resolveAllUses(bool ResolveUsers)207 void ReplaceableMetadataImpl::resolveAllUses(bool ResolveUsers) {
208 if (UseMap.empty())
209 return;
210
211 if (!ResolveUsers) {
212 UseMap.clear();
213 return;
214 }
215
216 // Copy out uses since UseMap could get touched below.
217 typedef std::pair<void *, std::pair<OwnerTy, uint64_t>> UseTy;
218 SmallVector<UseTy, 8> Uses(UseMap.begin(), UseMap.end());
219 std::sort(Uses.begin(), Uses.end(), [](const UseTy &L, const UseTy &R) {
220 return L.second.second < R.second.second;
221 });
222 UseMap.clear();
223 for (const auto &Pair : Uses) {
224 auto Owner = Pair.second.first;
225 if (!Owner)
226 continue;
227 if (Owner.is<MetadataAsValue *>())
228 continue;
229
230 // Resolve UniquableMDNodes that point at this.
231 auto *OwnerMD = dyn_cast<UniquableMDNode>(Owner.get<Metadata *>());
232 if (!OwnerMD)
233 continue;
234 if (OwnerMD->isResolved())
235 continue;
236 OwnerMD->decrementUnresolvedOperandCount();
237 }
238 }
239
getLocalFunction(Value * V)240 static Function *getLocalFunction(Value *V) {
241 assert(V && "Expected value");
242 if (auto *A = dyn_cast<Argument>(V))
243 return A->getParent();
244 if (BasicBlock *BB = cast<Instruction>(V)->getParent())
245 return BB->getParent();
246 return nullptr;
247 }
248
get(Value * V)249 ValueAsMetadata *ValueAsMetadata::get(Value *V) {
250 assert(V && "Unexpected null Value");
251
252 auto &Context = V->getContext();
253 auto *&Entry = Context.pImpl->ValuesAsMetadata[V];
254 if (!Entry) {
255 assert((isa<Constant>(V) || isa<Argument>(V) || isa<Instruction>(V)) &&
256 "Expected constant or function-local value");
257 assert(!V->NameAndIsUsedByMD.getInt() &&
258 "Expected this to be the only metadata use");
259 V->NameAndIsUsedByMD.setInt(true);
260 if (auto *C = dyn_cast<Constant>(V))
261 Entry = new ConstantAsMetadata(C);
262 else
263 Entry = new LocalAsMetadata(V);
264 }
265
266 return Entry;
267 }
268
getIfExists(Value * V)269 ValueAsMetadata *ValueAsMetadata::getIfExists(Value *V) {
270 assert(V && "Unexpected null Value");
271 return V->getContext().pImpl->ValuesAsMetadata.lookup(V);
272 }
273
handleDeletion(Value * V)274 void ValueAsMetadata::handleDeletion(Value *V) {
275 assert(V && "Expected valid value");
276
277 auto &Store = V->getType()->getContext().pImpl->ValuesAsMetadata;
278 auto I = Store.find(V);
279 if (I == Store.end())
280 return;
281
282 // Remove old entry from the map.
283 ValueAsMetadata *MD = I->second;
284 assert(MD && "Expected valid metadata");
285 assert(MD->getValue() == V && "Expected valid mapping");
286 Store.erase(I);
287
288 // Delete the metadata.
289 MD->replaceAllUsesWith(nullptr);
290 delete MD;
291 }
292
handleRAUW(Value * From,Value * To)293 void ValueAsMetadata::handleRAUW(Value *From, Value *To) {
294 assert(From && "Expected valid value");
295 assert(To && "Expected valid value");
296 assert(From != To && "Expected changed value");
297 assert(From->getType() == To->getType() && "Unexpected type change");
298
299 LLVMContext &Context = From->getType()->getContext();
300 auto &Store = Context.pImpl->ValuesAsMetadata;
301 auto I = Store.find(From);
302 if (I == Store.end()) {
303 assert(!From->NameAndIsUsedByMD.getInt() &&
304 "Expected From not to be used by metadata");
305 return;
306 }
307
308 // Remove old entry from the map.
309 assert(From->NameAndIsUsedByMD.getInt() &&
310 "Expected From to be used by metadata");
311 From->NameAndIsUsedByMD.setInt(false);
312 ValueAsMetadata *MD = I->second;
313 assert(MD && "Expected valid metadata");
314 assert(MD->getValue() == From && "Expected valid mapping");
315 Store.erase(I);
316
317 if (isa<LocalAsMetadata>(MD)) {
318 if (auto *C = dyn_cast<Constant>(To)) {
319 // Local became a constant.
320 MD->replaceAllUsesWith(ConstantAsMetadata::get(C));
321 delete MD;
322 return;
323 }
324 if (getLocalFunction(From) && getLocalFunction(To) &&
325 getLocalFunction(From) != getLocalFunction(To)) {
326 // Function changed.
327 MD->replaceAllUsesWith(nullptr);
328 delete MD;
329 return;
330 }
331 } else if (!isa<Constant>(To)) {
332 // Changed to function-local value.
333 MD->replaceAllUsesWith(nullptr);
334 delete MD;
335 return;
336 }
337
338 auto *&Entry = Store[To];
339 if (Entry) {
340 // The target already exists.
341 MD->replaceAllUsesWith(Entry);
342 delete MD;
343 return;
344 }
345
346 // Update MD in place (and update the map entry).
347 assert(!To->NameAndIsUsedByMD.getInt() &&
348 "Expected this to be the only metadata use");
349 To->NameAndIsUsedByMD.setInt(true);
350 MD->V = To;
351 Entry = MD;
352 }
353
354 //===----------------------------------------------------------------------===//
355 // MDString implementation.
356 //
357
get(LLVMContext & Context,StringRef Str)358 MDString *MDString::get(LLVMContext &Context, StringRef Str) {
359 auto &Store = Context.pImpl->MDStringCache;
360 auto I = Store.find(Str);
361 if (I != Store.end())
362 return &I->second;
363
364 auto *Entry =
365 StringMapEntry<MDString>::Create(Str, Store.getAllocator(), MDString());
366 bool WasInserted = Store.insert(Entry);
367 (void)WasInserted;
368 assert(WasInserted && "Expected entry to be inserted");
369 Entry->second.Entry = Entry;
370 return &Entry->second;
371 }
372
getString() const373 StringRef MDString::getString() const {
374 assert(Entry && "Expected to find string map entry");
375 return Entry->first();
376 }
377
378 //===----------------------------------------------------------------------===//
379 // MDNode implementation.
380 //
381
operator new(size_t Size,unsigned NumOps)382 void *MDNode::operator new(size_t Size, unsigned NumOps) {
383 void *Ptr = ::operator new(Size + NumOps * sizeof(MDOperand));
384 MDOperand *O = static_cast<MDOperand *>(Ptr);
385 for (MDOperand *E = O + NumOps; O != E; ++O)
386 (void)new (O) MDOperand;
387 return O;
388 }
389
operator delete(void * Mem)390 void MDNode::operator delete(void *Mem) {
391 MDNode *N = static_cast<MDNode *>(Mem);
392 MDOperand *O = static_cast<MDOperand *>(Mem);
393 for (MDOperand *E = O - N->NumOperands; O != E; --O)
394 (O - 1)->~MDOperand();
395 ::operator delete(O);
396 }
397
MDNode(LLVMContext & Context,unsigned ID,ArrayRef<Metadata * > MDs)398 MDNode::MDNode(LLVMContext &Context, unsigned ID, ArrayRef<Metadata *> MDs)
399 : Metadata(ID), Context(Context), NumOperands(MDs.size()),
400 MDNodeSubclassData(0) {
401 for (unsigned I = 0, E = MDs.size(); I != E; ++I)
402 setOperand(I, MDs[I]);
403 }
404
isResolved() const405 bool MDNode::isResolved() const {
406 if (isa<MDNodeFwdDecl>(this))
407 return false;
408 return cast<UniquableMDNode>(this)->isResolved();
409 }
410
isOperandUnresolved(Metadata * Op)411 static bool isOperandUnresolved(Metadata *Op) {
412 if (auto *N = dyn_cast_or_null<MDNode>(Op))
413 return !N->isResolved();
414 return false;
415 }
416
UniquableMDNode(LLVMContext & C,unsigned ID,ArrayRef<Metadata * > Vals,bool AllowRAUW)417 UniquableMDNode::UniquableMDNode(LLVMContext &C, unsigned ID,
418 ArrayRef<Metadata *> Vals, bool AllowRAUW)
419 : MDNode(C, ID, Vals) {
420 if (!AllowRAUW)
421 return;
422
423 // Check whether any operands are unresolved, requiring re-uniquing.
424 unsigned NumUnresolved = 0;
425 for (const auto &Op : operands())
426 NumUnresolved += unsigned(isOperandUnresolved(Op));
427
428 if (!NumUnresolved)
429 return;
430
431 ReplaceableUses.reset(new ReplaceableMetadataImpl);
432 SubclassData32 = NumUnresolved;
433 }
434
resolve()435 void UniquableMDNode::resolve() {
436 assert(!isResolved() && "Expected this to be unresolved");
437
438 // Move the map, so that this immediately looks resolved.
439 auto Uses = std::move(ReplaceableUses);
440 SubclassData32 = 0;
441 assert(isResolved() && "Expected this to be resolved");
442
443 // Drop RAUW support.
444 Uses->resolveAllUses();
445 }
446
resolveAfterOperandChange(Metadata * Old,Metadata * New)447 void UniquableMDNode::resolveAfterOperandChange(Metadata *Old, Metadata *New) {
448 assert(SubclassData32 != 0 && "Expected unresolved operands");
449
450 // Check if an operand was resolved.
451 if (!isOperandUnresolved(Old)) {
452 if (isOperandUnresolved(New))
453 // An operand was un-resolved!
454 ++SubclassData32;
455 } else if (!isOperandUnresolved(New))
456 decrementUnresolvedOperandCount();
457 }
458
decrementUnresolvedOperandCount()459 void UniquableMDNode::decrementUnresolvedOperandCount() {
460 if (!--SubclassData32)
461 // Last unresolved operand has just been resolved.
462 resolve();
463 }
464
resolveCycles()465 void UniquableMDNode::resolveCycles() {
466 if (isResolved())
467 return;
468
469 // Resolve this node immediately.
470 resolve();
471
472 // Resolve all operands.
473 for (const auto &Op : operands()) {
474 if (!Op)
475 continue;
476 assert(!isa<MDNodeFwdDecl>(Op) &&
477 "Expected all forward declarations to be resolved");
478 if (auto *N = dyn_cast<UniquableMDNode>(Op))
479 if (!N->isResolved())
480 N->resolveCycles();
481 }
482 }
483
recalculateHash()484 void MDTuple::recalculateHash() {
485 setHash(hash_combine_range(op_begin(), op_end()));
486 #ifndef NDEBUG
487 {
488 SmallVector<Metadata *, 8> MDs(op_begin(), op_end());
489 unsigned RawHash = hash_combine_range(MDs.begin(), MDs.end());
490 assert(getHash() == RawHash &&
491 "Expected hash of MDOperand to equal hash of Metadata*");
492 }
493 #endif
494 }
495
dropAllReferences()496 void MDNode::dropAllReferences() {
497 for (unsigned I = 0, E = NumOperands; I != E; ++I)
498 setOperand(I, nullptr);
499 if (auto *N = dyn_cast<UniquableMDNode>(this))
500 if (!N->isResolved()) {
501 N->ReplaceableUses->resolveAllUses(/* ResolveUsers */ false);
502 N->ReplaceableUses.reset();
503 }
504 }
505
506 namespace llvm {
507 /// \brief Make MDOperand transparent for hashing.
508 ///
509 /// This overload of an implementation detail of the hashing library makes
510 /// MDOperand hash to the same value as a \a Metadata pointer.
511 ///
512 /// Note that overloading \a hash_value() as follows:
513 ///
514 /// \code
515 /// size_t hash_value(const MDOperand &X) { return hash_value(X.get()); }
516 /// \endcode
517 ///
518 /// does not cause MDOperand to be transparent. In particular, a bare pointer
519 /// doesn't get hashed before it's combined, whereas \a MDOperand would.
get_hashable_data(const MDOperand & X)520 static const Metadata *get_hashable_data(const MDOperand &X) { return X.get(); }
521 }
522
handleChangedOperand(void * Ref,Metadata * New)523 void UniquableMDNode::handleChangedOperand(void *Ref, Metadata *New) {
524 unsigned Op = static_cast<MDOperand *>(Ref) - op_begin();
525 assert(Op < getNumOperands() && "Expected valid operand");
526
527 if (isStoredDistinctInContext()) {
528 assert(isResolved() && "Expected distinct node to be resolved");
529
530 // This node is not uniqued. Just set the operand and be done with it.
531 setOperand(Op, New);
532 return;
533 }
534
535 // This node is uniqued.
536 eraseFromStore();
537
538 Metadata *Old = getOperand(Op);
539 setOperand(Op, New);
540
541 // Drop uniquing for self-reference cycles.
542 if (New == this) {
543 storeDistinctInContext();
544 if (!isResolved())
545 resolve();
546 return;
547 }
548
549 // Re-unique the node.
550 auto *Uniqued = uniquify();
551 if (Uniqued == this) {
552 if (!isResolved())
553 resolveAfterOperandChange(Old, New);
554 return;
555 }
556
557 // Collision.
558 if (!isResolved()) {
559 // Still unresolved, so RAUW.
560 //
561 // First, clear out all operands to prevent any recursion (similar to
562 // dropAllReferences(), but we still need the use-list).
563 for (unsigned O = 0, E = getNumOperands(); O != E; ++O)
564 setOperand(O, nullptr);
565 ReplaceableUses->replaceAllUsesWith(Uniqued);
566 deleteAsSubclass();
567 return;
568 }
569
570 // Store in non-uniqued form if RAUW isn't possible.
571 storeDistinctInContext();
572 }
573
deleteAsSubclass()574 void UniquableMDNode::deleteAsSubclass() {
575 switch (getMetadataID()) {
576 default:
577 llvm_unreachable("Invalid subclass of UniquableMDNode");
578 #define HANDLE_UNIQUABLE_LEAF(CLASS) \
579 case CLASS##Kind: \
580 delete cast<CLASS>(this); \
581 break;
582 #include "llvm/IR/Metadata.def"
583 }
584 }
585
uniquify()586 UniquableMDNode *UniquableMDNode::uniquify() {
587 switch (getMetadataID()) {
588 default:
589 llvm_unreachable("Invalid subclass of UniquableMDNode");
590 #define HANDLE_UNIQUABLE_LEAF(CLASS) \
591 case CLASS##Kind: \
592 return cast<CLASS>(this)->uniquifyImpl();
593 #include "llvm/IR/Metadata.def"
594 }
595 }
596
eraseFromStore()597 void UniquableMDNode::eraseFromStore() {
598 switch (getMetadataID()) {
599 default:
600 llvm_unreachable("Invalid subclass of UniquableMDNode");
601 #define HANDLE_UNIQUABLE_LEAF(CLASS) \
602 case CLASS##Kind: \
603 cast<CLASS>(this)->eraseFromStoreImpl(); \
604 break;
605 #include "llvm/IR/Metadata.def"
606 }
607 }
608
getImpl(LLVMContext & Context,ArrayRef<Metadata * > MDs,bool ShouldCreate)609 MDTuple *MDTuple::getImpl(LLVMContext &Context, ArrayRef<Metadata *> MDs,
610 bool ShouldCreate) {
611 MDTupleInfo::KeyTy Key(MDs);
612
613 auto &Store = Context.pImpl->MDTuples;
614 auto I = Store.find_as(Key);
615 if (I != Store.end())
616 return *I;
617 if (!ShouldCreate)
618 return nullptr;
619
620 // Coallocate space for the node and Operands together, then placement new.
621 auto *N = new (MDs.size()) MDTuple(Context, MDs, /* AllowRAUW */ true);
622 N->setHash(Key.Hash);
623 Store.insert(N);
624 return N;
625 }
626
getDistinct(LLVMContext & Context,ArrayRef<Metadata * > MDs)627 MDTuple *MDTuple::getDistinct(LLVMContext &Context, ArrayRef<Metadata *> MDs) {
628 auto *N = new (MDs.size()) MDTuple(Context, MDs, /* AllowRAUW */ false);
629 N->storeDistinctInContext();
630 return N;
631 }
632
uniquifyImpl()633 MDTuple *MDTuple::uniquifyImpl() {
634 recalculateHash();
635 MDTupleInfo::KeyTy Key(this);
636
637 auto &Store = getContext().pImpl->MDTuples;
638 auto I = Store.find_as(Key);
639 if (I == Store.end()) {
640 Store.insert(this);
641 return this;
642 }
643 return *I;
644 }
645
eraseFromStoreImpl()646 void MDTuple::eraseFromStoreImpl() { getContext().pImpl->MDTuples.erase(this); }
647
MDLocation(LLVMContext & C,unsigned Line,unsigned Column,ArrayRef<Metadata * > MDs,bool AllowRAUW)648 MDLocation::MDLocation(LLVMContext &C, unsigned Line, unsigned Column,
649 ArrayRef<Metadata *> MDs, bool AllowRAUW)
650 : UniquableMDNode(C, MDLocationKind, MDs, AllowRAUW) {
651 assert((MDs.size() == 1 || MDs.size() == 2) &&
652 "Expected a scope and optional inlined-at");
653
654 // Set line and column.
655 assert(Line < (1u << 24) && "Expected 24-bit line");
656 assert(Column < (1u << 8) && "Expected 8-bit column");
657
658 MDNodeSubclassData = Line;
659 SubclassData16 = Column;
660 }
661
constructHelper(LLVMContext & Context,unsigned Line,unsigned Column,Metadata * Scope,Metadata * InlinedAt,bool AllowRAUW)662 MDLocation *MDLocation::constructHelper(LLVMContext &Context, unsigned Line,
663 unsigned Column, Metadata *Scope,
664 Metadata *InlinedAt, bool AllowRAUW) {
665 SmallVector<Metadata *, 2> Ops;
666 Ops.push_back(Scope);
667 if (InlinedAt)
668 Ops.push_back(InlinedAt);
669 return new (Ops.size()) MDLocation(Context, Line, Column, Ops, AllowRAUW);
670 }
671
adjustLine(unsigned & Line)672 static void adjustLine(unsigned &Line) {
673 // Set to unknown on overflow. Still use 24 bits for now.
674 if (Line >= (1u << 24))
675 Line = 0;
676 }
677
adjustColumn(unsigned & Column)678 static void adjustColumn(unsigned &Column) {
679 // Set to unknown on overflow. Still use 8 bits for now.
680 if (Column >= (1u << 8))
681 Column = 0;
682 }
683
getImpl(LLVMContext & Context,unsigned Line,unsigned Column,Metadata * Scope,Metadata * InlinedAt,bool ShouldCreate)684 MDLocation *MDLocation::getImpl(LLVMContext &Context, unsigned Line,
685 unsigned Column, Metadata *Scope,
686 Metadata *InlinedAt, bool ShouldCreate) {
687 // Fixup line/column.
688 adjustLine(Line);
689 adjustColumn(Column);
690
691 MDLocationInfo::KeyTy Key(Line, Column, Scope, InlinedAt);
692
693 auto &Store = Context.pImpl->MDLocations;
694 auto I = Store.find_as(Key);
695 if (I != Store.end())
696 return *I;
697 if (!ShouldCreate)
698 return nullptr;
699
700 auto *N = constructHelper(Context, Line, Column, Scope, InlinedAt,
701 /* AllowRAUW */ true);
702 Store.insert(N);
703 return N;
704 }
705
getDistinct(LLVMContext & Context,unsigned Line,unsigned Column,Metadata * Scope,Metadata * InlinedAt)706 MDLocation *MDLocation::getDistinct(LLVMContext &Context, unsigned Line,
707 unsigned Column, Metadata *Scope,
708 Metadata *InlinedAt) {
709 // Fixup line/column.
710 adjustLine(Line);
711 adjustColumn(Column);
712
713 auto *N = constructHelper(Context, Line, Column, Scope, InlinedAt,
714 /* AllowRAUW */ false);
715 N->storeDistinctInContext();
716 return N;
717 }
718
uniquifyImpl()719 MDLocation *MDLocation::uniquifyImpl() {
720 MDLocationInfo::KeyTy Key(this);
721
722 auto &Store = getContext().pImpl->MDLocations;
723 auto I = Store.find_as(Key);
724 if (I == Store.end()) {
725 Store.insert(this);
726 return this;
727 }
728 return *I;
729 }
730
eraseFromStoreImpl()731 void MDLocation::eraseFromStoreImpl() {
732 getContext().pImpl->MDLocations.erase(this);
733 }
734
getTemporary(LLVMContext & Context,ArrayRef<Metadata * > MDs)735 MDNodeFwdDecl *MDNode::getTemporary(LLVMContext &Context,
736 ArrayRef<Metadata *> MDs) {
737 return MDNodeFwdDecl::get(Context, MDs);
738 }
739
deleteTemporary(MDNode * N)740 void MDNode::deleteTemporary(MDNode *N) { delete cast<MDNodeFwdDecl>(N); }
741
storeDistinctInContext()742 void UniquableMDNode::storeDistinctInContext() {
743 assert(!IsDistinctInContext && "Expected newly distinct metadata");
744 IsDistinctInContext = true;
745 if (auto *T = dyn_cast<MDTuple>(this))
746 T->setHash(0);
747 getContext().pImpl->DistinctMDNodes.insert(this);
748 }
749
replaceOperandWith(unsigned I,Metadata * New)750 void MDNode::replaceOperandWith(unsigned I, Metadata *New) {
751 if (getOperand(I) == New)
752 return;
753
754 if (isDistinct()) {
755 setOperand(I, New);
756 return;
757 }
758
759 cast<UniquableMDNode>(this)->handleChangedOperand(mutable_begin() + I, New);
760 }
761
setOperand(unsigned I,Metadata * New)762 void MDNode::setOperand(unsigned I, Metadata *New) {
763 assert(I < NumOperands);
764 if (isStoredDistinctInContext() || isa<MDNodeFwdDecl>(this))
765 // No need for a callback, this isn't uniqued.
766 mutable_begin()[I].reset(New, nullptr);
767 else
768 mutable_begin()[I].reset(New, this);
769 }
770
771 /// \brief Get a node, or a self-reference that looks like it.
772 ///
773 /// Special handling for finding self-references, for use by \a
774 /// MDNode::concatenate() and \a MDNode::intersect() to maintain behaviour from
775 /// when self-referencing nodes were still uniqued. If the first operand has
776 /// the same operands as \c Ops, return the first operand instead.
getOrSelfReference(LLVMContext & Context,ArrayRef<Metadata * > Ops)777 static MDNode *getOrSelfReference(LLVMContext &Context,
778 ArrayRef<Metadata *> Ops) {
779 if (!Ops.empty())
780 if (MDNode *N = dyn_cast_or_null<MDNode>(Ops[0]))
781 if (N->getNumOperands() == Ops.size() && N == N->getOperand(0)) {
782 for (unsigned I = 1, E = Ops.size(); I != E; ++I)
783 if (Ops[I] != N->getOperand(I))
784 return MDNode::get(Context, Ops);
785 return N;
786 }
787
788 return MDNode::get(Context, Ops);
789 }
790
concatenate(MDNode * A,MDNode * B)791 MDNode *MDNode::concatenate(MDNode *A, MDNode *B) {
792 if (!A)
793 return B;
794 if (!B)
795 return A;
796
797 SmallVector<Metadata *, 4> MDs(A->getNumOperands() + B->getNumOperands());
798
799 unsigned j = 0;
800 for (unsigned i = 0, ie = A->getNumOperands(); i != ie; ++i)
801 MDs[j++] = A->getOperand(i);
802 for (unsigned i = 0, ie = B->getNumOperands(); i != ie; ++i)
803 MDs[j++] = B->getOperand(i);
804
805 // FIXME: This preserves long-standing behaviour, but is it really the right
806 // behaviour? Or was that an unintended side-effect of node uniquing?
807 return getOrSelfReference(A->getContext(), MDs);
808 }
809
intersect(MDNode * A,MDNode * B)810 MDNode *MDNode::intersect(MDNode *A, MDNode *B) {
811 if (!A || !B)
812 return nullptr;
813
814 SmallVector<Metadata *, 4> MDs;
815 for (unsigned i = 0, ie = A->getNumOperands(); i != ie; ++i) {
816 Metadata *MD = A->getOperand(i);
817 for (unsigned j = 0, je = B->getNumOperands(); j != je; ++j)
818 if (MD == B->getOperand(j)) {
819 MDs.push_back(MD);
820 break;
821 }
822 }
823
824 // FIXME: This preserves long-standing behaviour, but is it really the right
825 // behaviour? Or was that an unintended side-effect of node uniquing?
826 return getOrSelfReference(A->getContext(), MDs);
827 }
828
getMostGenericAliasScope(MDNode * A,MDNode * B)829 MDNode *MDNode::getMostGenericAliasScope(MDNode *A, MDNode *B) {
830 if (!A || !B)
831 return nullptr;
832
833 SmallVector<Metadata *, 4> MDs(B->op_begin(), B->op_end());
834 for (unsigned i = 0, ie = A->getNumOperands(); i != ie; ++i) {
835 Metadata *MD = A->getOperand(i);
836 bool insert = true;
837 for (unsigned j = 0, je = B->getNumOperands(); j != je; ++j)
838 if (MD == B->getOperand(j)) {
839 insert = false;
840 break;
841 }
842 if (insert)
843 MDs.push_back(MD);
844 }
845
846 // FIXME: This preserves long-standing behaviour, but is it really the right
847 // behaviour? Or was that an unintended side-effect of node uniquing?
848 return getOrSelfReference(A->getContext(), MDs);
849 }
850
getMostGenericFPMath(MDNode * A,MDNode * B)851 MDNode *MDNode::getMostGenericFPMath(MDNode *A, MDNode *B) {
852 if (!A || !B)
853 return nullptr;
854
855 APFloat AVal = mdconst::extract<ConstantFP>(A->getOperand(0))->getValueAPF();
856 APFloat BVal = mdconst::extract<ConstantFP>(B->getOperand(0))->getValueAPF();
857 if (AVal.compare(BVal) == APFloat::cmpLessThan)
858 return A;
859 return B;
860 }
861
isContiguous(const ConstantRange & A,const ConstantRange & B)862 static bool isContiguous(const ConstantRange &A, const ConstantRange &B) {
863 return A.getUpper() == B.getLower() || A.getLower() == B.getUpper();
864 }
865
canBeMerged(const ConstantRange & A,const ConstantRange & B)866 static bool canBeMerged(const ConstantRange &A, const ConstantRange &B) {
867 return !A.intersectWith(B).isEmptySet() || isContiguous(A, B);
868 }
869
tryMergeRange(SmallVectorImpl<ConstantInt * > & EndPoints,ConstantInt * Low,ConstantInt * High)870 static bool tryMergeRange(SmallVectorImpl<ConstantInt *> &EndPoints,
871 ConstantInt *Low, ConstantInt *High) {
872 ConstantRange NewRange(Low->getValue(), High->getValue());
873 unsigned Size = EndPoints.size();
874 APInt LB = EndPoints[Size - 2]->getValue();
875 APInt LE = EndPoints[Size - 1]->getValue();
876 ConstantRange LastRange(LB, LE);
877 if (canBeMerged(NewRange, LastRange)) {
878 ConstantRange Union = LastRange.unionWith(NewRange);
879 Type *Ty = High->getType();
880 EndPoints[Size - 2] =
881 cast<ConstantInt>(ConstantInt::get(Ty, Union.getLower()));
882 EndPoints[Size - 1] =
883 cast<ConstantInt>(ConstantInt::get(Ty, Union.getUpper()));
884 return true;
885 }
886 return false;
887 }
888
addRange(SmallVectorImpl<ConstantInt * > & EndPoints,ConstantInt * Low,ConstantInt * High)889 static void addRange(SmallVectorImpl<ConstantInt *> &EndPoints,
890 ConstantInt *Low, ConstantInt *High) {
891 if (!EndPoints.empty())
892 if (tryMergeRange(EndPoints, Low, High))
893 return;
894
895 EndPoints.push_back(Low);
896 EndPoints.push_back(High);
897 }
898
getMostGenericRange(MDNode * A,MDNode * B)899 MDNode *MDNode::getMostGenericRange(MDNode *A, MDNode *B) {
900 // Given two ranges, we want to compute the union of the ranges. This
901 // is slightly complitade by having to combine the intervals and merge
902 // the ones that overlap.
903
904 if (!A || !B)
905 return nullptr;
906
907 if (A == B)
908 return A;
909
910 // First, walk both lists in older of the lower boundary of each interval.
911 // At each step, try to merge the new interval to the last one we adedd.
912 SmallVector<ConstantInt *, 4> EndPoints;
913 int AI = 0;
914 int BI = 0;
915 int AN = A->getNumOperands() / 2;
916 int BN = B->getNumOperands() / 2;
917 while (AI < AN && BI < BN) {
918 ConstantInt *ALow = mdconst::extract<ConstantInt>(A->getOperand(2 * AI));
919 ConstantInt *BLow = mdconst::extract<ConstantInt>(B->getOperand(2 * BI));
920
921 if (ALow->getValue().slt(BLow->getValue())) {
922 addRange(EndPoints, ALow,
923 mdconst::extract<ConstantInt>(A->getOperand(2 * AI + 1)));
924 ++AI;
925 } else {
926 addRange(EndPoints, BLow,
927 mdconst::extract<ConstantInt>(B->getOperand(2 * BI + 1)));
928 ++BI;
929 }
930 }
931 while (AI < AN) {
932 addRange(EndPoints, mdconst::extract<ConstantInt>(A->getOperand(2 * AI)),
933 mdconst::extract<ConstantInt>(A->getOperand(2 * AI + 1)));
934 ++AI;
935 }
936 while (BI < BN) {
937 addRange(EndPoints, mdconst::extract<ConstantInt>(B->getOperand(2 * BI)),
938 mdconst::extract<ConstantInt>(B->getOperand(2 * BI + 1)));
939 ++BI;
940 }
941
942 // If we have more than 2 ranges (4 endpoints) we have to try to merge
943 // the last and first ones.
944 unsigned Size = EndPoints.size();
945 if (Size > 4) {
946 ConstantInt *FB = EndPoints[0];
947 ConstantInt *FE = EndPoints[1];
948 if (tryMergeRange(EndPoints, FB, FE)) {
949 for (unsigned i = 0; i < Size - 2; ++i) {
950 EndPoints[i] = EndPoints[i + 2];
951 }
952 EndPoints.resize(Size - 2);
953 }
954 }
955
956 // If in the end we have a single range, it is possible that it is now the
957 // full range. Just drop the metadata in that case.
958 if (EndPoints.size() == 2) {
959 ConstantRange Range(EndPoints[0]->getValue(), EndPoints[1]->getValue());
960 if (Range.isFullSet())
961 return nullptr;
962 }
963
964 SmallVector<Metadata *, 4> MDs;
965 MDs.reserve(EndPoints.size());
966 for (auto *I : EndPoints)
967 MDs.push_back(ConstantAsMetadata::get(I));
968 return MDNode::get(A->getContext(), MDs);
969 }
970
971 //===----------------------------------------------------------------------===//
972 // NamedMDNode implementation.
973 //
974
getNMDOps(void * Operands)975 static SmallVector<TrackingMDRef, 4> &getNMDOps(void *Operands) {
976 return *(SmallVector<TrackingMDRef, 4> *)Operands;
977 }
978
NamedMDNode(const Twine & N)979 NamedMDNode::NamedMDNode(const Twine &N)
980 : Name(N.str()), Parent(nullptr),
981 Operands(new SmallVector<TrackingMDRef, 4>()) {}
982
~NamedMDNode()983 NamedMDNode::~NamedMDNode() {
984 dropAllReferences();
985 delete &getNMDOps(Operands);
986 }
987
getNumOperands() const988 unsigned NamedMDNode::getNumOperands() const {
989 return (unsigned)getNMDOps(Operands).size();
990 }
991
getOperand(unsigned i) const992 MDNode *NamedMDNode::getOperand(unsigned i) const {
993 assert(i < getNumOperands() && "Invalid Operand number!");
994 auto *N = getNMDOps(Operands)[i].get();
995 return cast_or_null<MDNode>(N);
996 }
997
addOperand(MDNode * M)998 void NamedMDNode::addOperand(MDNode *M) { getNMDOps(Operands).emplace_back(M); }
999
setOperand(unsigned I,MDNode * New)1000 void NamedMDNode::setOperand(unsigned I, MDNode *New) {
1001 assert(I < getNumOperands() && "Invalid operand number");
1002 getNMDOps(Operands)[I].reset(New);
1003 }
1004
eraseFromParent()1005 void NamedMDNode::eraseFromParent() {
1006 getParent()->eraseNamedMetadata(this);
1007 }
1008
dropAllReferences()1009 void NamedMDNode::dropAllReferences() {
1010 getNMDOps(Operands).clear();
1011 }
1012
getName() const1013 StringRef NamedMDNode::getName() const {
1014 return StringRef(Name);
1015 }
1016
1017 //===----------------------------------------------------------------------===//
1018 // Instruction Metadata method implementations.
1019 //
1020
setMetadata(StringRef Kind,MDNode * Node)1021 void Instruction::setMetadata(StringRef Kind, MDNode *Node) {
1022 if (!Node && !hasMetadata())
1023 return;
1024 setMetadata(getContext().getMDKindID(Kind), Node);
1025 }
1026
getMetadataImpl(StringRef Kind) const1027 MDNode *Instruction::getMetadataImpl(StringRef Kind) const {
1028 return getMetadataImpl(getContext().getMDKindID(Kind));
1029 }
1030
dropUnknownMetadata(ArrayRef<unsigned> KnownIDs)1031 void Instruction::dropUnknownMetadata(ArrayRef<unsigned> KnownIDs) {
1032 SmallSet<unsigned, 5> KnownSet;
1033 KnownSet.insert(KnownIDs.begin(), KnownIDs.end());
1034
1035 // Drop debug if needed
1036 if (KnownSet.erase(LLVMContext::MD_dbg))
1037 DbgLoc = DebugLoc();
1038
1039 if (!hasMetadataHashEntry())
1040 return; // Nothing to remove!
1041
1042 DenseMap<const Instruction *, LLVMContextImpl::MDMapTy> &MetadataStore =
1043 getContext().pImpl->MetadataStore;
1044
1045 if (KnownSet.empty()) {
1046 // Just drop our entry at the store.
1047 MetadataStore.erase(this);
1048 setHasMetadataHashEntry(false);
1049 return;
1050 }
1051
1052 LLVMContextImpl::MDMapTy &Info = MetadataStore[this];
1053 unsigned I;
1054 unsigned E;
1055 // Walk the array and drop any metadata we don't know.
1056 for (I = 0, E = Info.size(); I != E;) {
1057 if (KnownSet.count(Info[I].first)) {
1058 ++I;
1059 continue;
1060 }
1061
1062 Info[I] = std::move(Info.back());
1063 Info.pop_back();
1064 --E;
1065 }
1066 assert(E == Info.size());
1067
1068 if (E == 0) {
1069 // Drop our entry at the store.
1070 MetadataStore.erase(this);
1071 setHasMetadataHashEntry(false);
1072 }
1073 }
1074
1075 /// setMetadata - Set the metadata of of the specified kind to the specified
1076 /// node. This updates/replaces metadata if already present, or removes it if
1077 /// Node is null.
setMetadata(unsigned KindID,MDNode * Node)1078 void Instruction::setMetadata(unsigned KindID, MDNode *Node) {
1079 if (!Node && !hasMetadata())
1080 return;
1081
1082 // Handle 'dbg' as a special case since it is not stored in the hash table.
1083 if (KindID == LLVMContext::MD_dbg) {
1084 DbgLoc = DebugLoc::getFromDILocation(Node);
1085 return;
1086 }
1087
1088 // Handle the case when we're adding/updating metadata on an instruction.
1089 if (Node) {
1090 LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
1091 assert(!Info.empty() == hasMetadataHashEntry() &&
1092 "HasMetadata bit is wonked");
1093 if (Info.empty()) {
1094 setHasMetadataHashEntry(true);
1095 } else {
1096 // Handle replacement of an existing value.
1097 for (auto &P : Info)
1098 if (P.first == KindID) {
1099 P.second.reset(Node);
1100 return;
1101 }
1102 }
1103
1104 // No replacement, just add it to the list.
1105 Info.emplace_back(std::piecewise_construct, std::make_tuple(KindID),
1106 std::make_tuple(Node));
1107 return;
1108 }
1109
1110 // Otherwise, we're removing metadata from an instruction.
1111 assert((hasMetadataHashEntry() ==
1112 (getContext().pImpl->MetadataStore.count(this) > 0)) &&
1113 "HasMetadata bit out of date!");
1114 if (!hasMetadataHashEntry())
1115 return; // Nothing to remove!
1116 LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
1117
1118 // Common case is removing the only entry.
1119 if (Info.size() == 1 && Info[0].first == KindID) {
1120 getContext().pImpl->MetadataStore.erase(this);
1121 setHasMetadataHashEntry(false);
1122 return;
1123 }
1124
1125 // Handle removal of an existing value.
1126 for (unsigned i = 0, e = Info.size(); i != e; ++i)
1127 if (Info[i].first == KindID) {
1128 Info[i] = std::move(Info.back());
1129 Info.pop_back();
1130 assert(!Info.empty() && "Removing last entry should be handled above");
1131 return;
1132 }
1133 // Otherwise, removing an entry that doesn't exist on the instruction.
1134 }
1135
setAAMetadata(const AAMDNodes & N)1136 void Instruction::setAAMetadata(const AAMDNodes &N) {
1137 setMetadata(LLVMContext::MD_tbaa, N.TBAA);
1138 setMetadata(LLVMContext::MD_alias_scope, N.Scope);
1139 setMetadata(LLVMContext::MD_noalias, N.NoAlias);
1140 }
1141
getMetadataImpl(unsigned KindID) const1142 MDNode *Instruction::getMetadataImpl(unsigned KindID) const {
1143 // Handle 'dbg' as a special case since it is not stored in the hash table.
1144 if (KindID == LLVMContext::MD_dbg)
1145 return DbgLoc.getAsMDNode();
1146
1147 if (!hasMetadataHashEntry()) return nullptr;
1148
1149 LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
1150 assert(!Info.empty() && "bit out of sync with hash table");
1151
1152 for (const auto &I : Info)
1153 if (I.first == KindID)
1154 return I.second;
1155 return nullptr;
1156 }
1157
getAllMetadataImpl(SmallVectorImpl<std::pair<unsigned,MDNode * >> & Result) const1158 void Instruction::getAllMetadataImpl(
1159 SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
1160 Result.clear();
1161
1162 // Handle 'dbg' as a special case since it is not stored in the hash table.
1163 if (!DbgLoc.isUnknown()) {
1164 Result.push_back(
1165 std::make_pair((unsigned)LLVMContext::MD_dbg, DbgLoc.getAsMDNode()));
1166 if (!hasMetadataHashEntry()) return;
1167 }
1168
1169 assert(hasMetadataHashEntry() &&
1170 getContext().pImpl->MetadataStore.count(this) &&
1171 "Shouldn't have called this");
1172 const LLVMContextImpl::MDMapTy &Info =
1173 getContext().pImpl->MetadataStore.find(this)->second;
1174 assert(!Info.empty() && "Shouldn't have called this");
1175
1176 Result.reserve(Result.size() + Info.size());
1177 for (auto &I : Info)
1178 Result.push_back(std::make_pair(I.first, cast<MDNode>(I.second.get())));
1179
1180 // Sort the resulting array so it is stable.
1181 if (Result.size() > 1)
1182 array_pod_sort(Result.begin(), Result.end());
1183 }
1184
getAllMetadataOtherThanDebugLocImpl(SmallVectorImpl<std::pair<unsigned,MDNode * >> & Result) const1185 void Instruction::getAllMetadataOtherThanDebugLocImpl(
1186 SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
1187 Result.clear();
1188 assert(hasMetadataHashEntry() &&
1189 getContext().pImpl->MetadataStore.count(this) &&
1190 "Shouldn't have called this");
1191 const LLVMContextImpl::MDMapTy &Info =
1192 getContext().pImpl->MetadataStore.find(this)->second;
1193 assert(!Info.empty() && "Shouldn't have called this");
1194 Result.reserve(Result.size() + Info.size());
1195 for (auto &I : Info)
1196 Result.push_back(std::make_pair(I.first, cast<MDNode>(I.second.get())));
1197
1198 // Sort the resulting array so it is stable.
1199 if (Result.size() > 1)
1200 array_pod_sort(Result.begin(), Result.end());
1201 }
1202
1203 /// clearMetadataHashEntries - Clear all hashtable-based metadata from
1204 /// this instruction.
clearMetadataHashEntries()1205 void Instruction::clearMetadataHashEntries() {
1206 assert(hasMetadataHashEntry() && "Caller should check");
1207 getContext().pImpl->MetadataStore.erase(this);
1208 setHasMetadataHashEntry(false);
1209 }
1210