LLVM  9.0.0svn
Metadata.cpp
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1 //===- Metadata.cpp - Implement Metadata classes --------------------------===//
2 //
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
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements the Metadata classes.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "LLVMContextImpl.h"
14 #include "MetadataImpl.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"
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"
50 #include <algorithm>
51 #include <cassert>
52 #include <cstddef>
53 #include <cstdint>
54 #include <iterator>
55 #include <tuple>
56 #include <type_traits>
57 #include <utility>
58 #include <vector>
59 
60 using namespace llvm;
61 
62 MetadataAsValue::MetadataAsValue(Type *Ty, Metadata *MD)
63  : Value(Ty, MetadataAsValueVal), MD(MD) {
64  track();
65 }
66 
68  getType()->getContext().pImpl->MetadataAsValues.erase(MD);
69  untrack();
70 }
71 
72 /// Canonicalize metadata arguments to intrinsics.
73 ///
74 /// To support bitcode upgrades (and assembly semantic sugar) for \a
75 /// MetadataAsValue, we need to canonicalize certain metadata.
76 ///
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.
80 ///
81 /// This maintains readability of bitcode from when metadata was a type of
82 /// value, and these bridges were unnecessary.
84  Metadata *MD) {
85  if (!MD)
86  // !{}
87  return MDNode::get(Context, None);
88 
89  // Return early if this isn't a single-operand MDNode.
90  auto *N = dyn_cast<MDNode>(MD);
91  if (!N || N->getNumOperands() != 1)
92  return MD;
93 
94  if (!N->getOperand(0))
95  // !{}
96  return MDNode::get(Context, None);
97 
98  if (auto *C = dyn_cast<ConstantAsMetadata>(N->getOperand(0)))
99  // Look through the MDNode.
100  return C;
101 
102  return MD;
103 }
104 
106  MD = canonicalizeMetadataForValue(Context, MD);
107  auto *&Entry = Context.pImpl->MetadataAsValues[MD];
108  if (!Entry)
109  Entry = new MetadataAsValue(Type::getMetadataTy(Context), MD);
110  return Entry;
111 }
112 
114  Metadata *MD) {
115  MD = canonicalizeMetadataForValue(Context, MD);
116  auto &Store = Context.pImpl->MetadataAsValues;
117  return Store.lookup(MD);
118 }
119 
120 void MetadataAsValue::handleChangedMetadata(Metadata *MD) {
121  LLVMContext &Context = getContext();
122  MD = canonicalizeMetadataForValue(Context, MD);
123  auto &Store = Context.pImpl->MetadataAsValues;
124 
125  // Stop tracking the old metadata.
126  Store.erase(this->MD);
127  untrack();
128  this->MD = nullptr;
129 
130  // Start tracking MD, or RAUW if necessary.
131  auto *&Entry = Store[MD];
132  if (Entry) {
133  replaceAllUsesWith(Entry);
134  delete this;
135  return;
136  }
137 
138  this->MD = MD;
139  track();
140  Entry = this;
141 }
142 
143 void MetadataAsValue::track() {
144  if (MD)
145  MetadataTracking::track(&MD, *MD, *this);
146 }
147 
148 void MetadataAsValue::untrack() {
149  if (MD)
151 }
152 
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);
159  return true;
160  }
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);
165  return true;
166  }
167  return false;
168 }
169 
171  assert(Ref && "Expected live reference");
172  if (auto *R = ReplaceableMetadataImpl::getIfExists(MD))
173  R->dropRef(Ref);
174  else if (auto *PH = dyn_cast<DistinctMDOperandPlaceholder>(&MD))
175  PH->Use = nullptr;
176 }
177 
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);
184  return true;
185  }
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");
190  return false;
191 }
192 
194  return ReplaceableMetadataImpl::isReplaceable(MD);
195 }
196 
197 void ReplaceableMetadataImpl::addRef(void *Ref, OwnerTy Owner) {
198  bool WasInserted =
199  UseMap.insert(std::make_pair(Ref, std::make_pair(Owner, NextIndex)))
200  .second;
201  (void)WasInserted;
202  assert(WasInserted && "Expected to add a reference");
203 
204  ++NextIndex;
205  assert(NextIndex != 0 && "Unexpected overflow");
206 }
207 
208 void ReplaceableMetadataImpl::dropRef(void *Ref) {
209  bool WasErased = UseMap.erase(Ref);
210  (void)WasErased;
211  assert(WasErased && "Expected to drop a reference");
212 }
213 
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;
219  UseMap.erase(I);
220  bool WasInserted = UseMap.insert(std::make_pair(New, OwnerAndIndex)).second;
221  (void)WasInserted;
222  assert(WasInserted && "Expected to add a reference");
223 
224  // Check that the references are direct if there's no owner.
225  (void)MD;
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");
230 }
231 
233  if (UseMap.empty())
234  return;
235 
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;
241  });
242  for (const auto &Pair : Uses) {
243  // Check that this Ref hasn't disappeared after RAUW (when updating a
244  // previous Ref).
245  if (!UseMap.count(Pair.first))
246  continue;
247 
248  OwnerTy Owner = Pair.second.first;
249  if (!Owner) {
250  // Update unowned tracking references directly.
251  Metadata *&Ref = *static_cast<Metadata **>(Pair.first);
252  Ref = MD;
253  if (MD)
255  UseMap.erase(Pair.first);
256  continue;
257  }
258 
259  // Check for MetadataAsValue.
260  if (Owner.is<MetadataAsValue *>()) {
261  Owner.get<MetadataAsValue *>()->handleChangedMetadata(MD);
262  continue;
263  }
264 
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); \
271  continue;
272 #include "llvm/IR/Metadata.def"
273  default:
274  llvm_unreachable("Invalid metadata subclass");
275  }
276  }
277  assert(UseMap.empty() && "Expected all uses to be replaced");
278 }
279 
281  if (UseMap.empty())
282  return;
283 
284  if (!ResolveUsers) {
285  UseMap.clear();
286  return;
287  }
288 
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;
294  });
295  UseMap.clear();
296  for (const auto &Pair : Uses) {
297  auto Owner = Pair.second.first;
298  if (!Owner)
299  continue;
300  if (Owner.is<MetadataAsValue *>())
301  continue;
302 
303  // Resolve MDNodes that point at this.
304  auto *OwnerMD = dyn_cast<MDNode>(Owner.get<Metadata *>());
305  if (!OwnerMD)
306  continue;
307  if (OwnerMD->isResolved())
308  continue;
309  OwnerMD->decrementUnresolvedOperandCount();
310  }
311 }
312 
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);
317 }
318 
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);
323 }
324 
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);
329 }
330 
332  assert(V && "Expected value");
333  if (auto *A = dyn_cast<Argument>(V)) {
334  if (auto *Fn = A->getParent())
335  return Fn->getSubprogram();
336  return nullptr;
337  }
338 
339  if (BasicBlock *BB = cast<Instruction>(V)->getParent()) {
340  if (auto *Fn = BB->getParent())
341  return Fn->getSubprogram();
342  return nullptr;
343  }
344 
345  return nullptr;
346 }
347 
349  assert(V && "Unexpected null Value");
350 
351  auto &Context = V->getContext();
352  auto *&Entry = Context.pImpl->ValuesAsMetadata[V];
353  if (!Entry) {
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);
360  else
361  Entry = new LocalAsMetadata(V);
362  }
363 
364  return Entry;
365 }
366 
368  assert(V && "Unexpected null Value");
369  return V->getContext().pImpl->ValuesAsMetadata.lookup(V);
370 }
371 
373  assert(V && "Expected valid value");
374 
375  auto &Store = V->getType()->getContext().pImpl->ValuesAsMetadata;
376  auto I = Store.find(V);
377  if (I == Store.end())
378  return;
379 
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");
384  Store.erase(I);
385 
386  // Delete the metadata.
387  MD->replaceAllUsesWith(nullptr);
388  delete MD;
389 }
390 
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");
396 
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");
402  return;
403  }
404 
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");
411  Store.erase(I);
412 
413  if (isa<LocalAsMetadata>(MD)) {
414  if (auto *C = dyn_cast<Constant>(To)) {
415  // Local became a constant.
417  delete MD;
418  return;
419  }
422  // DISubprogram changed.
423  MD->replaceAllUsesWith(nullptr);
424  delete MD;
425  return;
426  }
427  } else if (!isa<Constant>(To)) {
428  // Changed to function-local value.
429  MD->replaceAllUsesWith(nullptr);
430  delete MD;
431  return;
432  }
433 
434  auto *&Entry = Store[To];
435  if (Entry) {
436  // The target already exists.
438  delete MD;
439  return;
440  }
441 
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;
445  MD->V = To;
446  Entry = MD;
447 }
448 
449 //===----------------------------------------------------------------------===//
450 // MDString implementation.
451 //
452 
454  auto &Store = Context.pImpl->MDStringCache;
455  auto I = Store.try_emplace(Str);
456  auto &MapEntry = I.first->getValue();
457  if (!I.second)
458  return &MapEntry;
459  MapEntry.Entry = &*I.first;
460  return &MapEntry;
461 }
462 
464  assert(Entry && "Expected to find string map entry");
465  return Entry->first();
466 }
467 
468 //===----------------------------------------------------------------------===//
469 // MDNode implementation.
470 //
471 
472 // Assert that the MDNode types will not be unaligned by the objects
473 // prepended to them.
474 #define HANDLE_MDNODE_LEAF(CLASS) \
475  static_assert( \
476  alignof(uint64_t) >= alignof(CLASS), \
477  "Alignment is insufficient after objects prepended to " #CLASS);
478 #include "llvm/IR/Metadata.def"
479 
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
483  // above)
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;
489  return Ptr;
490 }
491 
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));
496 
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);
501 }
502 
503 MDNode::MDNode(LLVMContext &Context, unsigned ID, StorageType Storage,
505  : Metadata(ID, Storage), NumOperands(Ops1.size() + Ops2.size()),
506  NumUnresolved(0), Context(Context) {
507  unsigned Op = 0;
508  for (Metadata *MD : Ops1)
509  setOperand(Op++, MD);
510  for (Metadata *MD : Ops2)
511  setOperand(Op++, MD);
512 
513  if (!isUniqued())
514  return;
515 
516  // Count the unresolved operands. If there are any, RAUW support will be
517  // added lazily on first reference.
518  countUnresolvedOperands();
519 }
520 
521 TempMDNode MDNode::clone() const {
522  switch (getMetadataID()) {
523  default:
524  llvm_unreachable("Invalid MDNode subclass");
525 #define HANDLE_MDNODE_LEAF(CLASS) \
526  case CLASS##Kind: \
527  return cast<CLASS>(this)->cloneImpl();
528 #include "llvm/IR/Metadata.def"
529  }
530 }
531 
533  if (auto *N = dyn_cast_or_null<MDNode>(Op))
534  return !N->isResolved();
535  return false;
536 }
537 
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);
542 }
543 
544 void MDNode::makeUniqued() {
545  assert(isTemporary() && "Expected this to be temporary");
546  assert(!isResolved() && "Expected this to be unresolved");
547 
548  // Enable uniquing callbacks.
549  for (auto &Op : mutable_operands())
550  Op.reset(Op.get(), this);
551 
552  // Make this 'uniqued'.
553  Storage = Uniqued;
554  countUnresolvedOperands();
555  if (!NumUnresolved) {
556  dropReplaceableUses();
557  assert(isResolved() && "Expected this to be resolved");
558  }
559 
560  assert(isUniqued() && "Expected this to be uniqued");
561 }
562 
563 void MDNode::makeDistinct() {
564  assert(isTemporary() && "Expected this to be temporary");
565  assert(!isResolved() && "Expected this to be unresolved");
566 
567  // Drop RAUW support and store as a distinct node.
568  dropReplaceableUses();
570 
571  assert(isDistinct() && "Expected this to be distinct");
572  assert(isResolved() && "Expected this to be resolved");
573 }
574 
576  assert(isUniqued() && "Expected this to be uniqued");
577  assert(!isResolved() && "Expected this to be unresolved");
578 
579  NumUnresolved = 0;
580  dropReplaceableUses();
581 
582  assert(isResolved() && "Expected this to be resolved");
583 }
584 
585 void MDNode::dropReplaceableUses() {
586  assert(!NumUnresolved && "Unexpected unresolved operand");
587 
588  // Drop any RAUW support.
589  if (Context.hasReplaceableUses())
590  Context.takeReplaceableUses()->resolveAllUses();
591 }
592 
593 void MDNode::resolveAfterOperandChange(Metadata *Old, Metadata *New) {
594  assert(isUniqued() && "Expected this to be uniqued");
595  assert(NumUnresolved != 0 && "Expected unresolved operands");
596 
597  // Check if an operand was resolved.
598  if (!isOperandUnresolved(Old)) {
599  if (isOperandUnresolved(New))
600  // An operand was un-resolved!
601  ++NumUnresolved;
602  } else if (!isOperandUnresolved(New))
603  decrementUnresolvedOperandCount();
604 }
605 
606 void MDNode::decrementUnresolvedOperandCount() {
607  assert(!isResolved() && "Expected this to be unresolved");
608  if (isTemporary())
609  return;
610 
611  assert(isUniqued() && "Expected this to be uniqued");
612  if (--NumUnresolved)
613  return;
614 
615  // Last unresolved operand has just been resolved.
616  dropReplaceableUses();
617  assert(isResolved() && "Expected this to become resolved");
618 }
619 
621  if (isResolved())
622  return;
623 
624  // Resolve this node immediately.
625  resolve();
626 
627  // Resolve all operands.
628  for (const auto &Op : operands()) {
629  auto *N = dyn_cast_or_null<MDNode>(Op);
630  if (!N)
631  continue;
632 
633  assert(!N->isTemporary() &&
634  "Expected all forward declarations to be resolved");
635  if (!N->isResolved())
636  N->resolveCycles();
637  }
638 }
639 
640 static bool hasSelfReference(MDNode *N) {
641  for (Metadata *MD : N->operands())
642  if (MD == N)
643  return true;
644  return false;
645 }
646 
647 MDNode *MDNode::replaceWithPermanentImpl() {
648  switch (getMetadataID()) {
649  default:
650  // If this type isn't uniquable, replace with a distinct node.
651  return replaceWithDistinctImpl();
652 
653 #define HANDLE_MDNODE_LEAF_UNIQUABLE(CLASS) \
654  case CLASS##Kind: \
655  break;
656 #include "llvm/IR/Metadata.def"
657  }
658 
659  // Even if this type is uniquable, self-references have to be distinct.
660  if (hasSelfReference(this))
661  return replaceWithDistinctImpl();
662  return replaceWithUniquedImpl();
663 }
664 
665 MDNode *MDNode::replaceWithUniquedImpl() {
666  // Try to uniquify in place.
667  MDNode *UniquedNode = uniquify();
668 
669  if (UniquedNode == this) {
670  makeUniqued();
671  return this;
672  }
673 
674  // Collision, so RAUW instead.
675  replaceAllUsesWith(UniquedNode);
676  deleteAsSubclass();
677  return UniquedNode;
678 }
679 
680 MDNode *MDNode::replaceWithDistinctImpl() {
681  makeDistinct();
682  return this;
683 }
684 
685 void MDTuple::recalculateHash() {
686  setHash(MDTupleInfo::KeyTy::calculateHash(this));
687 }
688 
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();
695  }
696 }
697 
698 void MDNode::handleChangedOperand(void *Ref, Metadata *New) {
699  unsigned Op = static_cast<MDOperand *>(Ref) - op_begin();
700  assert(Op < getNumOperands() && "Expected valid operand");
701 
702  if (!isUniqued()) {
703  // This node is not uniqued. Just set the operand and be done with it.
704  setOperand(Op, New);
705  return;
706  }
707 
708  // This node is uniqued.
709  eraseFromStore();
710 
711  Metadata *Old = getOperand(Op);
712  setOperand(Op, New);
713 
714  // Drop uniquing for self-reference cycles and deleted constants.
715  if (New == this || (!New && Old && isa<ConstantAsMetadata>(Old))) {
716  if (!isResolved())
717  resolve();
719  return;
720  }
721 
722  // Re-unique the node.
723  auto *Uniqued = uniquify();
724  if (Uniqued == this) {
725  if (!isResolved())
726  resolveAfterOperandChange(Old, New);
727  return;
728  }
729 
730  // Collision.
731  if (!isResolved()) {
732  // Still unresolved, so RAUW.
733  //
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())
740  deleteAsSubclass();
741  return;
742  }
743 
744  // Store in non-uniqued form if RAUW isn't possible.
746 }
747 
748 void MDNode::deleteAsSubclass() {
749  switch (getMetadataID()) {
750  default:
751  llvm_unreachable("Invalid subclass of MDNode");
752 #define HANDLE_MDNODE_LEAF(CLASS) \
753  case CLASS##Kind: \
754  delete cast<CLASS>(this); \
755  break;
756 #include "llvm/IR/Metadata.def"
757  }
758 }
759 
760 template <class T, class InfoT>
762  if (T *U = getUniqued(Store, N))
763  return U;
764 
765  Store.insert(N);
766  return N;
767 }
768 
769 template <class NodeTy> struct MDNode::HasCachedHash {
770  using Yes = char[1];
771  using No = char[2];
772  template <class U, U Val> struct SFINAE {};
773 
774  template <class U>
775  static Yes &check(SFINAE<void (U::*)(unsigned), &U::setHash> *);
776  template <class U> static No &check(...);
777 
778  static const bool value = sizeof(check<NodeTy>(nullptr)) == sizeof(Yes);
779 };
780 
781 MDNode *MDNode::uniquify() {
782  assert(!hasSelfReference(this) && "Cannot uniquify a self-referencing node");
783 
784  // Try to insert into uniquing store.
785  switch (getMetadataID()) {
786  default:
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); \
795  }
796 #include "llvm/IR/Metadata.def"
797  }
798 }
799 
800 void MDNode::eraseFromStore() {
801  switch (getMetadataID()) {
802  default:
803  llvm_unreachable("Invalid or non-uniquable subclass of MDNode");
804 #define HANDLE_MDNODE_LEAF_UNIQUABLE(CLASS) \
805  case CLASS##Kind: \
806  getContext().pImpl->CLASS##s.erase(cast<CLASS>(this)); \
807  break;
808 #include "llvm/IR/Metadata.def"
809  }
810 }
811 
812 MDTuple *MDTuple::getImpl(LLVMContext &Context, ArrayRef<Metadata *> MDs,
813  StorageType Storage, bool ShouldCreate) {
814  unsigned Hash = 0;
815  if (Storage == Uniqued) {
816  MDTupleInfo::KeyTy Key(MDs);
817  if (auto *N = getUniqued(Context.pImpl->MDTuples, Key))
818  return N;
819  if (!ShouldCreate)
820  return nullptr;
821  Hash = Key.getHash();
822  } else {
823  assert(ShouldCreate && "Expected non-uniqued nodes to always be created");
824  }
825 
826  return storeImpl(new (MDs.size()) MDTuple(Context, Storage, Hash, MDs),
827  Storage, Context.pImpl->MDTuples);
828 }
829 
831  assert(N->isTemporary() && "Expected temporary node");
832  N->replaceAllUsesWith(nullptr);
833  N->deleteAsSubclass();
834 }
835 
837  assert(!Context.hasReplaceableUses() && "Unexpected replaceable uses");
838  assert(!NumUnresolved && "Unexpected unresolved nodes");
839  Storage = Distinct;
840  assert(isResolved() && "Expected this to be resolved");
841 
842  // Reset the hash.
843  switch (getMetadataID()) {
844  default:
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); \
850  break; \
851  }
852 #include "llvm/IR/Metadata.def"
853  }
854 
855  getContext().pImpl->DistinctMDNodes.push_back(this);
856 }
857 
858 void MDNode::replaceOperandWith(unsigned I, Metadata *New) {
859  if (getOperand(I) == New)
860  return;
861 
862  if (!isUniqued()) {
863  setOperand(I, New);
864  return;
865  }
866 
867  handleChangedOperand(mutable_begin() + I, New);
868 }
869 
870 void MDNode::setOperand(unsigned I, Metadata *New) {
871  assert(I < NumOperands);
872  mutable_begin()[I].reset(New, isUniqued() ? this : nullptr);
873 }
874 
875 /// Get a node or a self-reference that looks like it.
876 ///
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.
882  ArrayRef<Metadata *> Ops) {
883  if (!Ops.empty())
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);
889  return N;
890  }
891 
892  return MDNode::get(Context, Ops);
893 }
894 
896  if (!A)
897  return B;
898  if (!B)
899  return A;
900 
902  MDs.insert(B->op_begin(), B->op_end());
903 
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());
907 }
908 
910  if (!A || !B)
911  return nullptr;
912 
914  SmallPtrSet<Metadata *, 4> BSet(B->op_begin(), B->op_end());
915  MDs.remove_if([&](Metadata *MD) { return !is_contained(BSet, MD); });
916 
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());
920 }
921 
923  if (!A || !B)
924  return nullptr;
925 
926  return concatenate(A, B);
927 }
928 
930  if (!A || !B)
931  return nullptr;
932 
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)
936  return A;
937  return B;
938 }
939 
940 static bool isContiguous(const ConstantRange &A, const ConstantRange &B) {
941  return A.getUpper() == B.getLower() || A.getLower() == B.getUpper();
942 }
943 
944 static bool canBeMerged(const ConstantRange &A, const ConstantRange &B) {
945  return !A.intersectWith(B).isEmptySet() || isContiguous(A, B);
946 }
947 
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()));
962  return true;
963  }
964  return false;
965 }
966 
968  ConstantInt *Low, ConstantInt *High) {
969  if (!EndPoints.empty())
970  if (tryMergeRange(EndPoints, Low, High))
971  return;
972 
973  EndPoints.push_back(Low);
974  EndPoints.push_back(High);
975 }
976 
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.
981 
982  if (!A || !B)
983  return nullptr;
984 
985  if (A == B)
986  return A;
987 
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.
991  int AI = 0;
992  int BI = 0;
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));
998 
999  if (ALow->getValue().slt(BLow->getValue())) {
1000  addRange(EndPoints, ALow,
1001  mdconst::extract<ConstantInt>(A->getOperand(2 * AI + 1)));
1002  ++AI;
1003  } else {
1004  addRange(EndPoints, BLow,
1005  mdconst::extract<ConstantInt>(B->getOperand(2 * BI + 1)));
1006  ++BI;
1007  }
1008  }
1009  while (AI < AN) {
1010  addRange(EndPoints, mdconst::extract<ConstantInt>(A->getOperand(2 * AI)),
1011  mdconst::extract<ConstantInt>(A->getOperand(2 * AI + 1)));
1012  ++AI;
1013  }
1014  while (BI < BN) {
1015  addRange(EndPoints, mdconst::extract<ConstantInt>(B->getOperand(2 * BI)),
1016  mdconst::extract<ConstantInt>(B->getOperand(2 * BI + 1)));
1017  ++BI;
1018  }
1019 
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();
1023  if (Size > 4) {
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];
1029  }
1030  EndPoints.resize(Size - 2);
1031  }
1032  }
1033 
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())
1039  return nullptr;
1040  }
1041 
1043  MDs.reserve(EndPoints.size());
1044  for (auto *I : EndPoints)
1046  return MDNode::get(A->getContext(), MDs);
1047 }
1048 
1050  if (!A || !B)
1051  return nullptr;
1052 
1053  ConstantInt *AVal = mdconst::extract<ConstantInt>(A->getOperand(0));
1054  ConstantInt *BVal = mdconst::extract<ConstantInt>(B->getOperand(0));
1055  if (AVal->getZExtValue() < BVal->getZExtValue())
1056  return A;
1057  return B;
1058 }
1059 
1060 //===----------------------------------------------------------------------===//
1061 // NamedMDNode implementation.
1062 //
1063 
1064 static SmallVector<TrackingMDRef, 4> &getNMDOps(void *Operands) {
1065  return *(SmallVector<TrackingMDRef, 4> *)Operands;
1066 }
1067 
1068 NamedMDNode::NamedMDNode(const Twine &N)
1069  : Name(N.str()), Operands(new SmallVector<TrackingMDRef, 4>()) {}
1070 
1073  delete &getNMDOps(Operands);
1074 }
1075 
1077  return (unsigned)getNMDOps(Operands).size();
1078 }
1079 
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);
1084 }
1085 
1086 void NamedMDNode::addOperand(MDNode *M) { getNMDOps(Operands).emplace_back(M); }
1087 
1088 void NamedMDNode::setOperand(unsigned I, MDNode *New) {
1089  assert(I < getNumOperands() && "Invalid operand number");
1090  getNMDOps(Operands)[I].reset(New);
1091 }
1092 
1093 void NamedMDNode::eraseFromParent() { getParent()->eraseNamedMetadata(this); }
1094 
1095 void NamedMDNode::clearOperands() { getNMDOps(Operands).clear(); }
1096 
1098 
1099 //===----------------------------------------------------------------------===//
1100 // Instruction Metadata method implementations.
1101 //
1102 void MDAttachmentMap::set(unsigned ID, MDNode &MD) {
1103  for (auto &I : Attachments)
1104  if (I.first == ID) {
1105  I.second.reset(&MD);
1106  return;
1107  }
1108  Attachments.emplace_back(std::piecewise_construct, std::make_tuple(ID),
1109  std::make_tuple(&MD));
1110 }
1111 
1112 bool MDAttachmentMap::erase(unsigned ID) {
1113  if (empty())
1114  return false;
1115 
1116  // Common case is one/last value.
1117  if (Attachments.back().first == ID) {
1118  Attachments.pop_back();
1119  return true;
1120  }
1121 
1122  for (auto I = Attachments.begin(), E = std::prev(Attachments.end()); I != E;
1123  ++I)
1124  if (I->first == ID) {
1125  *I = std::move(Attachments.back());
1126  Attachments.pop_back();
1127  return true;
1128  }
1129 
1130  return false;
1131 }
1132 
1134  for (const auto &I : Attachments)
1135  if (I.first == ID)
1136  return I.second;
1137  return nullptr;
1138 }
1139 
1141  SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
1142  Result.append(Attachments.begin(), Attachments.end());
1143 
1144  // Sort the resulting array so it is stable.
1145  if (Result.size() > 1)
1146  array_pod_sort(Result.begin(), Result.end());
1147 }
1148 
1150  Attachments.push_back({ID, TrackingMDNodeRef(&MD)});
1151 }
1152 
1154  for (const auto &A : Attachments)
1155  if (A.MDKind == ID)
1156  return A.Node;
1157  return nullptr;
1158 }
1159 
1161  SmallVectorImpl<MDNode *> &Result) const {
1162  for (const auto &A : Attachments)
1163  if (A.MDKind == ID)
1164  Result.push_back(A.Node);
1165 }
1166 
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());
1172  return Changed;
1173 }
1174 
1176  SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
1177  for (const auto &A : Attachments)
1178  Result.emplace_back(A.MDKind, A.Node);
1179 
1180  // Sort the resulting array so it is stable with respect to metadata IDs. We
1181  // need to preserve the original insertion order though.
1183  Result.begin(), Result.end(),
1184  [](const std::pair<unsigned, MDNode *> &A,
1185  const std::pair<unsigned, MDNode *> &B) { return A.first < B.first; });
1186 }
1187 
1189  if (!Node && !hasMetadata())
1190  return;
1191  setMetadata(getContext().getMDKindID(Kind), Node);
1192 }
1193 
1194 MDNode *Instruction::getMetadataImpl(StringRef Kind) const {
1195  return getMetadataImpl(getContext().getMDKindID(Kind));
1196 }
1197 
1199  if (!hasMetadataHashEntry())
1200  return; // Nothing to remove!
1201 
1202  auto &InstructionMetadata = getContext().pImpl->InstructionMetadata;
1203 
1204  SmallSet<unsigned, 4> KnownSet;
1205  KnownSet.insert(KnownIDs.begin(), KnownIDs.end());
1206  if (KnownSet.empty()) {
1207  // Just drop our entry at the store.
1208  InstructionMetadata.erase(this);
1209  setHasMetadataHashEntry(false);
1210  return;
1211  }
1212 
1213  auto &Info = InstructionMetadata[this];
1214  Info.remove_if([&KnownSet](const std::pair<unsigned, TrackingMDNodeRef> &I) {
1215  return !KnownSet.count(I.first);
1216  });
1217 
1218  if (Info.empty()) {
1219  // Drop our entry at the store.
1220  InstructionMetadata.erase(this);
1221  setHasMetadataHashEntry(false);
1222  }
1223 }
1224 
1225 void Instruction::setMetadata(unsigned KindID, MDNode *Node) {
1226  if (!Node && !hasMetadata())
1227  return;
1228 
1229  // Handle 'dbg' as a special case since it is not stored in the hash table.
1230  if (KindID == LLVMContext::MD_dbg) {
1231  DbgLoc = DebugLoc(Node);
1232  return;
1233  }
1234 
1235  // Handle the case when we're adding/updating metadata on an instruction.
1236  if (Node) {
1237  auto &Info = getContext().pImpl->InstructionMetadata[this];
1238  assert(!Info.empty() == hasMetadataHashEntry() &&
1239  "HasMetadata bit is wonked");
1240  if (Info.empty())
1241  setHasMetadataHashEntry(true);
1242  Info.set(KindID, *Node);
1243  return;
1244  }
1245 
1246  // Otherwise, we're removing metadata from an instruction.
1247  assert((hasMetadataHashEntry() ==
1248  (getContext().pImpl->InstructionMetadata.count(this) > 0)) &&
1249  "HasMetadata bit out of date!");
1250  if (!hasMetadataHashEntry())
1251  return; // Nothing to remove!
1252  auto &Info = getContext().pImpl->InstructionMetadata[this];
1253 
1254  // Handle removal of an existing value.
1255  Info.erase(KindID);
1256 
1257  if (!Info.empty())
1258  return;
1259 
1260  getContext().pImpl->InstructionMetadata.erase(this);
1261  setHasMetadataHashEntry(false);
1262 }
1263 
1268 }
1269 
1270 MDNode *Instruction::getMetadataImpl(unsigned KindID) const {
1271  // Handle 'dbg' as a special case since it is not stored in the hash table.
1272  if (KindID == LLVMContext::MD_dbg)
1273  return DbgLoc.getAsMDNode();
1274 
1275  if (!hasMetadataHashEntry())
1276  return nullptr;
1277  auto &Info = getContext().pImpl->InstructionMetadata[this];
1278  assert(!Info.empty() && "bit out of sync with hash table");
1279 
1280  return Info.lookup(KindID);
1281 }
1282 
1283 void Instruction::getAllMetadataImpl(
1284  SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
1285  Result.clear();
1286 
1287  // Handle 'dbg' as a special case since it is not stored in the hash table.
1288  if (DbgLoc) {
1289  Result.push_back(
1290  std::make_pair((unsigned)LLVMContext::MD_dbg, DbgLoc.getAsMDNode()));
1291  if (!hasMetadataHashEntry())
1292  return;
1293  }
1294 
1295  assert(hasMetadataHashEntry() &&
1296  getContext().pImpl->InstructionMetadata.count(this) &&
1297  "Shouldn't have called this");
1298  const auto &Info = getContext().pImpl->InstructionMetadata.find(this)->second;
1299  assert(!Info.empty() && "Shouldn't have called this");
1300  Info.getAll(Result);
1301 }
1302 
1303 void Instruction::getAllMetadataOtherThanDebugLocImpl(
1304  SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
1305  Result.clear();
1306  assert(hasMetadataHashEntry() &&
1307  getContext().pImpl->InstructionMetadata.count(this) &&
1308  "Shouldn't have called this");
1309  const auto &Info = getContext().pImpl->InstructionMetadata.find(this)->second;
1310  assert(!Info.empty() && "Shouldn't have called this");
1311  Info.getAll(Result);
1312 }
1313 
1314 bool Instruction::extractProfMetadata(uint64_t &TrueVal,
1315  uint64_t &FalseVal) const {
1316  assert(
1317  (getOpcode() == Instruction::Br || getOpcode() == Instruction::Select) &&
1318  "Looking for branch weights on something besides branch or select");
1319 
1320  auto *ProfileData = getMetadata(LLVMContext::MD_prof);
1321  if (!ProfileData || ProfileData->getNumOperands() != 3)
1322  return false;
1323 
1324  auto *ProfDataName = dyn_cast<MDString>(ProfileData->getOperand(0));
1325  if (!ProfDataName || !ProfDataName->getString().equals("branch_weights"))
1326  return false;
1327 
1328  auto *CITrue = mdconst::dyn_extract<ConstantInt>(ProfileData->getOperand(1));
1329  auto *CIFalse = mdconst::dyn_extract<ConstantInt>(ProfileData->getOperand(2));
1330  if (!CITrue || !CIFalse)
1331  return false;
1332 
1333  TrueVal = CITrue->getValue().getZExtValue();
1334  FalseVal = CIFalse->getValue().getZExtValue();
1335 
1336  return true;
1337 }
1338 
1339 bool Instruction::extractProfTotalWeight(uint64_t &TotalVal) const {
1340  assert((getOpcode() == Instruction::Br ||
1343  getOpcode() == Instruction::Invoke ||
1344  getOpcode() == Instruction::Switch) &&
1345  "Looking for branch weights on something besides branch");
1346 
1347  TotalVal = 0;
1348  auto *ProfileData = getMetadata(LLVMContext::MD_prof);
1349  if (!ProfileData)
1350  return false;
1351 
1352  auto *ProfDataName = dyn_cast<MDString>(ProfileData->getOperand(0));
1353  if (!ProfDataName)
1354  return false;
1355 
1356  if (ProfDataName->getString().equals("branch_weights")) {
1357  TotalVal = 0;
1358  for (unsigned i = 1; i < ProfileData->getNumOperands(); i++) {
1359  auto *V = mdconst::dyn_extract<ConstantInt>(ProfileData->getOperand(i));
1360  if (!V)
1361  return false;
1362  TotalVal += V->getValue().getZExtValue();
1363  }
1364  return true;
1365  } else if (ProfDataName->getString().equals("VP") &&
1366  ProfileData->getNumOperands() > 3) {
1367  TotalVal = mdconst::dyn_extract<ConstantInt>(ProfileData->getOperand(2))
1368  ->getValue()
1369  .getZExtValue();
1370  return true;
1371  }
1372  return false;
1373 }
1374 
1375 void Instruction::clearMetadataHashEntries() {
1376  assert(hasMetadataHashEntry() && "Caller should check");
1377  getContext().pImpl->InstructionMetadata.erase(this);
1378  setHasMetadataHashEntry(false);
1379 }
1380 
1381 void GlobalObject::getMetadata(unsigned KindID,
1382  SmallVectorImpl<MDNode *> &MDs) const {
1383  if (hasMetadata())
1384  getContext().pImpl->GlobalObjectMetadata[this].get(KindID, MDs);
1385 }
1386 
1388  SmallVectorImpl<MDNode *> &MDs) const {
1389  if (hasMetadata())
1390  getMetadata(getContext().getMDKindID(Kind), MDs);
1391 }
1392 
1393 void GlobalObject::addMetadata(unsigned KindID, MDNode &MD) {
1394  if (!hasMetadata())
1395  setHasMetadataHashEntry(true);
1396 
1397  getContext().pImpl->GlobalObjectMetadata[this].insert(KindID, MD);
1398 }
1399 
1401  addMetadata(getContext().getMDKindID(Kind), MD);
1402 }
1403 
1404 bool GlobalObject::eraseMetadata(unsigned KindID) {
1405  // Nothing to unset.
1406  if (!hasMetadata())
1407  return false;
1408 
1409  auto &Store = getContext().pImpl->GlobalObjectMetadata[this];
1410  bool Changed = Store.erase(KindID);
1411  if (Store.empty())
1412  clearMetadata();
1413  return Changed;
1414 }
1415 
1417  SmallVectorImpl<std::pair<unsigned, MDNode *>> &MDs) const {
1418  MDs.clear();
1419 
1420  if (!hasMetadata())
1421  return;
1422 
1423  getContext().pImpl->GlobalObjectMetadata[this].getAll(MDs);
1424 }
1425 
1427  if (!hasMetadata())
1428  return;
1429  getContext().pImpl->GlobalObjectMetadata.erase(this);
1430  setHasMetadataHashEntry(false);
1431 }
1432 
1433 void GlobalObject::setMetadata(unsigned KindID, MDNode *N) {
1434  eraseMetadata(KindID);
1435  if (N)
1436  addMetadata(KindID, *N);
1437 }
1438 
1440  setMetadata(getContext().getMDKindID(Kind), N);
1441 }
1442 
1443 MDNode *GlobalObject::getMetadata(unsigned KindID) const {
1444  if (hasMetadata())
1445  return getContext().pImpl->GlobalObjectMetadata[this].lookup(KindID);
1446  return nullptr;
1447 }
1448 
1450  return getMetadata(getContext().getMDKindID(Kind));
1451 }
1452 
1453 void GlobalObject::copyMetadata(const GlobalObject *Other, unsigned Offset) {
1455  Other->getAllMetadata(MDs);
1456  for (auto &MD : MDs) {
1457  // We need to adjust the type metadata offset.
1458  if (Offset != 0 && MD.first == LLVMContext::MD_type) {
1459  auto *OffsetConst = cast<ConstantInt>(
1460  cast<ConstantAsMetadata>(MD.second->getOperand(0))->getValue());
1461  Metadata *TypeId = MD.second->getOperand(1);
1462  auto *NewOffsetMD = ConstantAsMetadata::get(ConstantInt::get(
1463  OffsetConst->getType(), OffsetConst->getValue() + Offset));
1464  addMetadata(LLVMContext::MD_type,
1465  *MDNode::get(getContext(), {NewOffsetMD, TypeId}));
1466  continue;
1467  }
1468  // If an offset adjustment was specified we need to modify the DIExpression
1469  // to prepend the adjustment:
1470  // !DIExpression(DW_OP_plus, Offset, [original expr])
1471  auto *Attachment = MD.second;
1472  if (Offset != 0 && MD.first == LLVMContext::MD_dbg) {
1473  DIGlobalVariable *GV = dyn_cast<DIGlobalVariable>(Attachment);
1474  DIExpression *E = nullptr;
1475  if (!GV) {
1476  auto *GVE = cast<DIGlobalVariableExpression>(Attachment);
1477  GV = GVE->getVariable();
1478  E = GVE->getExpression();
1479  }
1480  ArrayRef<uint64_t> OrigElements;
1481  if (E)
1482  OrigElements = E->getElements();
1483  std::vector<uint64_t> Elements(OrigElements.size() + 2);
1484  Elements[0] = dwarf::DW_OP_plus_uconst;
1485  Elements[1] = Offset;
1486  llvm::copy(OrigElements, Elements.begin() + 2);
1487  E = DIExpression::get(getContext(), Elements);
1488  Attachment = DIGlobalVariableExpression::get(getContext(), GV, E);
1489  }
1490  addMetadata(MD.first, *Attachment);
1491  }
1492 }
1493 
1495  addMetadata(
1499  Type::getInt64Ty(getContext()), Offset)),
1500  TypeID}));
1501 }
1502 
1505 }
1506 
1508  return cast_or_null<DISubprogram>(getMetadata(LLVMContext::MD_dbg));
1509 }
1510 
1512  if (DISubprogram *SP = getSubprogram()) {
1513  if (DICompileUnit *CU = SP->getUnit()) {
1514  return CU->getDebugInfoForProfiling();
1515  }
1516  }
1517  return false;
1518 }
1519 
1521  addMetadata(LLVMContext::MD_dbg, *GV);
1522 }
1523 
1527  getMetadata(LLVMContext::MD_dbg, MDs);
1528  for (MDNode *MD : MDs)
1529  GVs.push_back(cast<DIGlobalVariableExpression>(MD));
1530 }
uint64_t CallInst * C
IntegerType * getType() const
getType - Specialize the getType() method to always return an IntegerType, which reduces the amount o...
Definition: Constants.h:171
static void deleteTemporary(MDNode *N)
Deallocate a node created by getTemporary.
Definition: Metadata.cpp:830
bool isUniqued() const
Definition: Metadata.h:941
Tracking metadata reference owned by Metadata.
Definition: Metadata.h:710
unsigned char Storage
Storage flag for non-uniqued, otherwise unowned, metadata.
Definition: Metadata.h:68
static MDTuple * get(LLVMContext &Context, ArrayRef< Metadata *> MDs)
Definition: Metadata.h:1132
bool isDistinct() const
Definition: Metadata.h:942
StringMap< MDString, BumpPtrAllocator > MDStringCache
LLVMContext & Context
MDNode * Scope
The tag for alias scope specification (used with noalias).
Definition: Metadata.h:660
MDNode * getOperand(unsigned i) const
Definition: Metadata.cpp:1080
This class represents lattice values for constants.
Definition: AllocatorList.h:23
const APInt & getUpper() const
Return the upper value for this range.
MDNode * TBAA
The tag for type-based alias analysis.
Definition: Metadata.h:657
iterator begin() const
Definition: ArrayRef.h:136
void replaceOperandWith(unsigned I, Metadata *New)
Replace a specific operand.
Definition: Metadata.cpp:858
amdgpu Simplify well known AMD library false FunctionCallee Value const Twine & Name
static MDString * get(LLVMContext &Context, StringRef Str)
Definition: Metadata.cpp:453
void clearOperands()
Drop all references to this node&#39;s operands.
Definition: Metadata.cpp:1095
Implements a dense probed hash-table based set.
Definition: DenseSet.h:249
std::unique_ptr< ReplaceableMetadataImpl > takeReplaceableUses()
Drop RAUW support.
Definition: Metadata.h:829
DenseMap< Value *, ValueAsMetadata * > ValuesAsMetadata
static MDNode * getMostGenericAliasScope(MDNode *A, MDNode *B)
Definition: Metadata.cpp:922
bool slt(const APInt &RHS) const
Signed less than comparison.
Definition: APInt.h:1203
void addOperand(MDNode *M)
Definition: Metadata.cpp:1086
This file contains the declarations for metadata subclasses.
void storeDistinctInContext()
Definition: Metadata.cpp:836
LLVMContext & getContext() const
All values hold a context through their type.
Definition: Value.cpp:709
auto count_if(R &&Range, UnaryPredicate P) -> typename std::iterator_traits< decltype(adl_begin(Range))>::difference_type
Wrapper function around std::count_if to count the number of times an element satisfying a given pred...
Definition: STLExtras.h:1259
void dropAllReferences()
Definition: Metadata.cpp:689
Shared implementation of use-lists for replaceable metadata.
Definition: Metadata.h:278
A debug info location.
Definition: DebugLoc.h:33
Metadata node.
Definition: Metadata.h:863
static bool canBeMerged(const ConstantRange &A, const ConstantRange &B)
Definition: Metadata.cpp:944
const MDOperand & getOperand(unsigned I) const
Definition: Metadata.h:1068
uint64_t alignTo(uint64_t Value, uint64_t Align, uint64_t Skew=0)
Returns the next integer (mod 2**64) that is greater than or equal to Value and is a multiple of Alig...
Definition: MathExtras.h:684
static T * storeImpl(T *N, StorageType Storage, StoreT &Store)
Definition: MetadataImpl.h:42
static IntegerType * getInt64Ty(LLVMContext &C)
Definition: Type.cpp:176
void setOperand(unsigned I, Metadata *New)
Set an operand.
Definition: Metadata.cpp:870
static Type * getMetadataTy(LLVMContext &C)
Definition: Type.cpp:165
void getAllMetadata(SmallVectorImpl< std::pair< unsigned, MDNode *>> &MDs) const
Appends all attachments for the global to MDs, sorting by attachment ID.
Definition: Metadata.cpp:1416
void reserve(size_type N)
Definition: SmallVector.h:369
void setOperand(unsigned I, MDNode *New)
Definition: Metadata.cpp:1088
op_iterator op_end() const
Definition: Metadata.h:1062
uint64_t High
Tuple of metadata.
Definition: Metadata.h:1105
TempMDNode clone() const
Create a (temporary) clone of this.
Definition: Metadata.cpp:521
LLVMContext & getContext() const
Return the LLVMContext in which this type was uniqued.
Definition: Type.h:129
void set(unsigned ID, MDNode &MD)
Set an attachment to a particular node.
Definition: Metadata.cpp:1102
TypedTrackingMDRef< MDNode > TrackingMDNodeRef
void copyMetadata(const GlobalObject *Src, unsigned Offset)
Copy metadata from Src, adjusting offsets by Offset.
Definition: Metadata.cpp:1453
DenseMap< const Instruction *, MDAttachmentMap > InstructionMetadata
Collection of per-instruction metadata used in this context.
LLVM_NODISCARD bool empty() const
Definition: SmallSet.h:155
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:80
bool isResolved() const
Check if node is fully resolved.
Definition: Metadata.h:939
void eraseFromParent()
Drop all references and remove the node from parent module.
Definition: Metadata.cpp:1093
static Optional< unsigned > getOpcode(ArrayRef< VPValue *> Values)
Returns the opcode of Values or ~0 if they do not all agree.
Definition: VPlanSLP.cpp:196
This class consists of common code factored out of the SmallVector class to reduce code duplication b...
Definition: APFloat.h:41
static bool track(Metadata *&MD)
Track the reference to metadata.
Definition: Metadata.h:220
The access may reference the value stored in memory.
MDNode * getMetadata(unsigned KindID) const
Get the current metadata attachments for the given kind, if any.
Definition: Metadata.cpp:1443
TypeID
Definitions of all of the base types for the Type system.
Definition: Type.h:54
unsigned getNumOperands() const
Definition: Metadata.cpp:1076
std::vector< MDNode * > DistinctMDNodes
This file implements a class to represent arbitrary precision integral constant values and operations...
void resolveCycles()
Resolve cycles.
Definition: Metadata.cpp:620
op_iterator op_begin() const
Definition: Metadata.h:1058
static Metadata * canonicalizeMetadataForValue(LLVMContext &Context, Metadata *MD)
Canonicalize metadata arguments to intrinsics.
Definition: Metadata.cpp:83
Subprogram description.
Key
PAL metadata keys.
static void handleRAUW(Value *From, Value *To)
Definition: Metadata.cpp:391
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:244
static SmallVector< TrackingMDRef, 4 > & getNMDOps(void *Operands)
Definition: Metadata.cpp:1064
void dropUnknownNonDebugMetadata()
Definition: Instruction.h:289
op_range operands() const
Definition: Metadata.h:1066
ConstantRange intersectWith(const ConstantRange &CR, PreferredRangeType Type=Smallest) const
Return the range that results from the intersection of this range with another range.
LLVMContext & getContext() const
Definition: Metadata.h:923
unsigned getMetadataID() const
Definition: Metadata.h:99
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory)...
Definition: APInt.h:32
const APInt & getValue() const
Return the constant as an APInt value reference.
Definition: Constants.h:137
static MDNode * intersect(MDNode *A, MDNode *B)
Definition: Metadata.cpp:909
static T * uniquifyImpl(T *N, DenseSet< T *, InfoT > &Store)
Definition: Metadata.cpp:761
bool extractProfTotalWeight(uint64_t &TotalVal) const
Retrieve total raw weight values of a branch.
Definition: Metadata.cpp:1339
Value wrapper in the Metadata hierarchy.
Definition: Metadata.h:338
void replaceAllUsesWith(Metadata *MD)
RAUW a temporary.
Definition: Metadata.h:948
MDNode * lookup(unsigned ID) const
Get a particular attachment (if any).
Definition: Metadata.cpp:1133
static ConstantAsMetadata * get(Constant *C)
Definition: Metadata.h:409
Analysis containing CSE Info
Definition: CSEInfo.cpp:20
void resolve()
Resolve a unique, unresolved node.
Definition: Metadata.cpp:575
static MetadataAsValue * get(LLVMContext &Context, Metadata *MD)
Definition: Metadata.cpp:105
StringRef getString() const
Definition: Metadata.cpp:463
MDNode * lookup(unsigned ID) const
Returns the first attachment with the given ID or nullptr if no such attachment exists.
Definition: Metadata.cpp:1153
static MDTuple * get(LLVMContext &Context, ArrayRef< Metadata *> MDs)
Definition: Metadata.h:1165
bool isDebugInfoForProfiling() const
Returns true if we should emit debug info for profiling.
Definition: Metadata.cpp:1511
static MDNode * getMostGenericRange(MDNode *A, MDNode *B)
Definition: Metadata.cpp:977
void setSubprogram(DISubprogram *SP)
Set the attached subprogram.
Definition: Metadata.cpp:1503
void array_pod_sort(IteratorTy Start, IteratorTy End)
array_pod_sort - This sorts an array with the specified start and end extent.
Definition: STLExtras.h:1082
static T * getUniqued(DenseSet< T *, InfoT > &Store, const typename InfoT::KeyTy &Key)
Definition: MetadataImpl.h:22
void resolveAllUses(bool ResolveUsers=true)
Resolve all uses of this.
Definition: Metadata.cpp:280
uint64_t getZExtValue() const
Return the constant as a 64-bit unsigned integer value after it has been zero extended as appropriate...
Definition: Constants.h:148
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
void addTypeMetadata(unsigned Offset, Metadata *TypeID)
Definition: Metadata.cpp:1494
static ValueAsMetadata * getIfExists(Value *V)
Definition: Metadata.cpp:367
static MetadataAsValue * getIfExists(LLVMContext &Context, Metadata *MD)
Definition: Metadata.cpp:113
void setAAMetadata(const AAMDNodes &N)
Sets the metadata on this instruction from the AAMDNodes structure.
Definition: Metadata.cpp:1264
LLVM Basic Block Representation.
Definition: BasicBlock.h:57
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:45
This is an important class for using LLVM in a threaded context.
Definition: LLVMContext.h:64
DISubprogram * getSubprogram() const
Get the attached subprogram.
Definition: Metadata.cpp:1507
static MDNode * getMostGenericAlignmentOrDereferenceable(MDNode *A, MDNode *B)
Definition: Metadata.cpp:1049
size_t size() const
size - Get the array size.
Definition: ArrayRef.h:148
static bool isContiguous(const ConstantRange &A, const ConstantRange &B)
Definition: Metadata.cpp:940
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
SmallSet - This maintains a set of unique values, optimizing for the case when the set is small (less...
Definition: SmallSet.h:134
This file contains the declarations for the subclasses of Constant, which represent the different fla...
void getDebugInfo(SmallVectorImpl< DIGlobalVariableExpression *> &GVs) const
Fill the vector with all debug info attachements.
Definition: Metadata.cpp:1524
StorageType
Active type of storage.
Definition: Metadata.h:65
A pair of DIGlobalVariable and DIExpression.
void getAll(SmallVectorImpl< std::pair< unsigned, MDNode *>> &Result) const
Appends all attachments for the global to Result, sorting by attachment ID.
Definition: Metadata.cpp:1175
This file declares a class to represent arbitrary precision floating point values and provide a varie...
static bool retrack(Metadata *&MD, Metadata *&New)
Move tracking from one reference to another.
Definition: Metadata.h:256
bool isFullSet() const
Return true if this set contains all of the elements possible for this data-type. ...
std::pair< NoneType, bool > insert(const T &V)
insert - Insert an element into the set if it isn&#39;t already there.
Definition: SmallSet.h:180
Metadata wrapper in the Value hierarchy.
Definition: Metadata.h:173
auto remove_if(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range))
Provide wrappers to std::remove_if which take ranges instead of having to pass begin/end explicitly...
Definition: STLExtras.h:1225
static DISubprogram * getSubprogram(bool IsDistinct, Ts &&... Args)
Definition: DIBuilder.cpp:745
size_t size() const
Definition: SmallVector.h:52
static wasm::ValType getType(const TargetRegisterClass *RC)
C setMetadata(LLVMContext::MD_range, MDNode::get(Context, LowAndHigh))
Value * getValue() const
Definition: Metadata.h:378
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
void setMetadata(unsigned KindID, MDNode *Node)
Set the metadata of the specified kind to the specified node.
Definition: Metadata.cpp:1225
mutable_op_range mutable_operands()
Definition: Metadata.h:897
LLVMContextImpl *const pImpl
Definition: LLVMContext.h:66
static bool isOperandUnresolved(Metadata *Op)
Definition: Metadata.cpp:532
void sort(IteratorTy Start, IteratorTy End)
Definition: STLExtras.h:1115
constexpr bool empty(const T &RangeOrContainer)
Test whether RangeOrContainer is empty. Similar to C++17 std::empty.
Definition: STLExtras.h:209
bool isEmptySet() const
Return true if this set contains no members.
DenseMap< Metadata *, MetadataAsValue * > MetadataAsValues
bool hasReplaceableUses() const
Whether this contains RAUW support.
Definition: Metadata.h:790
DenseMap< const GlobalObject *, MDGlobalAttachmentMap > GlobalObjectMetadata
Collection of per-GlobalObject metadata used in this context.
A SetVector that performs no allocations if smaller than a certain size.
Definition: SetVector.h:297
bool erase(unsigned ID)
Definition: Metadata.cpp:1167
static MDNode * getOrSelfReference(LLVMContext &Context, ArrayRef< Metadata *> Ops)
Get a node or a self-reference that looks like it.
Definition: Metadata.cpp:881
SmallPtrSet - This class implements a set which is optimized for holding SmallSize or less elements...
Definition: SmallPtrSet.h:417
This is the shared class of boolean and integer constants.
Definition: Constants.h:83
auto size(R &&Range, typename std::enable_if< std::is_same< typename std::iterator_traits< decltype(Range.begin())>::iterator_category, std::random_access_iterator_tag >::value, void >::type *=nullptr) -> decltype(std::distance(Range.begin(), Range.end()))
Get the size of a range.
Definition: STLExtras.h:1166
BlockVerifier::State From
unsigned IsUsedByMD
Definition: Value.h:117
MDNode(LLVMContext &Context, unsigned ID, StorageType Storage, ArrayRef< Metadata *> Ops1, ArrayRef< Metadata *> Ops2=None)
Definition: Metadata.cpp:503
static ValueAsMetadata * get(Value *V)
Definition: Metadata.cpp:348
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:841
Module.h This file contains the declarations for the Module class.
This class represents a range of values.
Definition: ConstantRange.h:47
void addMetadata(unsigned KindID, MDNode &MD)
Add a metadata attachment.
Definition: Metadata.cpp:1393
iterator end() const
Definition: ArrayRef.h:137
A collection of metadata nodes that might be associated with a memory access used by the alias-analys...
Definition: Metadata.h:643
MDNode * NoAlias
The tag specifying the noalias scope.
Definition: Metadata.h:663
static Constant * get(Type *Ty, uint64_t V, bool isSigned=false)
If Ty is a vector type, return a Constant with a splat of the given value.
Definition: Constants.cpp:631
void reset()
Definition: Metadata.h:726
DWARF expression.
void get(unsigned ID, SmallVectorImpl< MDNode *> &Result) const
Appends all attachments with the given ID to Result in insertion order.
Definition: Metadata.cpp:1160
static void untrack(Metadata *&MD)
Stop tracking a reference to metadata.
Definition: Metadata.h:245
Class for arbitrary precision integers.
Definition: APInt.h:69
void insert(unsigned ID, MDNode &MD)
Definition: Metadata.cpp:1149
StringRef getName() const
Definition: Metadata.cpp:1097
void setMetadata(unsigned KindID, MDNode *MD)
Set a particular kind of metadata attachment.
Definition: Metadata.cpp:1433
MDOperand * mutable_begin()
Definition: Metadata.h:892
void getAll(SmallVectorImpl< std::pair< unsigned, MDNode *>> &Result) const
Copy out all the attachments.
Definition: Metadata.cpp:1140
LLVM_NODISCARD bool empty() const
Definition: SmallVector.h:55
void replaceAllUsesWith(Metadata *MD)
Handle collisions after Value::replaceAllUsesWith().
Definition: Metadata.h:391
static MDNode * concatenate(MDNode *A, MDNode *B)
Methods for metadata merging.
Definition: Metadata.cpp:895
const APInt & getLower() const
Return the lower value for this range.
#define I(x, y, z)
Definition: MD5.cpp:58
#define N
LLVM_NODISCARD std::enable_if<!is_simple_type< Y >::value, typename cast_retty< X, const Y >::ret_type >::type dyn_cast(const Y &Val)
Definition: Casting.h:332
uint32_t Size
Definition: Profile.cpp:46
void replaceAllUsesWith(Metadata *MD)
Replace all uses of this with MD.
Definition: Metadata.cpp:232
std::string str() const
Return the twine contents as a std::string.
Definition: Twine.cpp:17
static void addRange(SmallVectorImpl< ConstantInt *> &EndPoints, ConstantInt *Low, ConstantInt *High)
Definition: Metadata.cpp:967
ConstantRange unionWith(const ConstantRange &CR, PreferredRangeType Type=Smallest) const
Return the range that results from the union of this range with another range.
static bool hasSelfReference(MDNode *N)
Definition: Metadata.cpp:640
T get() const
Returns the value of the specified pointer type.
Definition: PointerUnion.h:134
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
void stable_sort(R &&Range)
Definition: STLExtras.h:1309
static void handleDeletion(Value *V)
Definition: Metadata.cpp:372
LLVM Value Representation.
Definition: Value.h:72
bool erase(unsigned ID)
Remove an attachment.
Definition: Metadata.cpp:1112
static const Function * getParent(const Value *V)
bool isTemporary() const
Definition: Metadata.h:943
void addDebugInfo(DIGlobalVariableExpression *GV)
Attach a DIGlobalVariableExpression.
Definition: Metadata.cpp:1520
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
A single uniqued string.
Definition: Metadata.h:603
int is() const
Test if the Union currently holds the type matching T.
Definition: PointerUnion.h:122
bool eraseMetadata(unsigned KindID)
Erase all metadata attachments with the given kind.
Definition: Metadata.cpp:1404
static bool isReplaceable(const Metadata &MD)
Check whether metadata is replaceable.
Definition: Metadata.cpp:193
unsigned getNumOperands() const
Return number of MDNode operands.
Definition: Metadata.h:1074
bool extractProfMetadata(uint64_t &TrueVal, uint64_t &FalseVal) const
Retrieve the raw weight values of a conditional branch or select.
Definition: Metadata.cpp:1314
static bool tryMergeRange(SmallVectorImpl< ConstantInt *> &EndPoints, ConstantInt *Low, ConstantInt *High)
Definition: Metadata.cpp:948
static MDNode * getMostGenericFPMath(MDNode *A, MDNode *B)
Definition: Metadata.cpp:929
OutputIt copy(R &&Range, OutputIt Out)
Definition: STLExtras.h:1237
ReplaceableMetadataImpl * getReplaceableUses() const
Definition: Metadata.h:800
Root of the metadata hierarchy.
Definition: Metadata.h:57
static DISubprogram * getLocalFunctionMetadata(Value *V)
Definition: Metadata.cpp:331
bool empty() const
empty - Check if the array is empty.
Definition: ArrayRef.h:143
cmpResult compare(const APFloat &RHS) const
Definition: APFloat.h:1101
A discriminated union of two pointer types, with the discriminator in the low bit of the pointer...
Definition: PointerUnion.h:86
size_type count(const T &V) const
count - Return 1 if the element is in the set, 0 otherwise.
Definition: SmallSet.h:164
void resize(size_type N)
Definition: SmallVector.h:344
bool is_contained(R &&Range, const E &Element)
Wrapper function around std::find to detect if an element exists in a container.
Definition: STLExtras.h:1244