LLVM  9.0.0svn
IRMover.cpp
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1 //===- lib/Linker/IRMover.cpp ---------------------------------------------===//
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 #include "llvm/Linker/IRMover.h"
10 #include "LinkDiagnosticInfo.h"
11 #include "llvm/ADT/SetVector.h"
12 #include "llvm/ADT/SmallString.h"
13 #include "llvm/ADT/Triple.h"
14 #include "llvm/IR/Constants.h"
15 #include "llvm/IR/DebugInfo.h"
17 #include "llvm/IR/GVMaterializer.h"
18 #include "llvm/IR/Intrinsics.h"
19 #include "llvm/IR/TypeFinder.h"
20 #include "llvm/Support/Error.h"
22 #include <utility>
23 using namespace llvm;
24 
25 //===----------------------------------------------------------------------===//
26 // TypeMap implementation.
27 //===----------------------------------------------------------------------===//
28 
29 namespace {
30 class TypeMapTy : public ValueMapTypeRemapper {
31  /// This is a mapping from a source type to a destination type to use.
32  DenseMap<Type *, Type *> MappedTypes;
33 
34  /// When checking to see if two subgraphs are isomorphic, we speculatively
35  /// add types to MappedTypes, but keep track of them here in case we need to
36  /// roll back.
37  SmallVector<Type *, 16> SpeculativeTypes;
38 
39  SmallVector<StructType *, 16> SpeculativeDstOpaqueTypes;
40 
41  /// This is a list of non-opaque structs in the source module that are mapped
42  /// to an opaque struct in the destination module.
43  SmallVector<StructType *, 16> SrcDefinitionsToResolve;
44 
45  /// This is the set of opaque types in the destination modules who are
46  /// getting a body from the source module.
47  SmallPtrSet<StructType *, 16> DstResolvedOpaqueTypes;
48 
49 public:
50  TypeMapTy(IRMover::IdentifiedStructTypeSet &DstStructTypesSet)
51  : DstStructTypesSet(DstStructTypesSet) {}
52 
53  IRMover::IdentifiedStructTypeSet &DstStructTypesSet;
54  /// Indicate that the specified type in the destination module is conceptually
55  /// equivalent to the specified type in the source module.
56  void addTypeMapping(Type *DstTy, Type *SrcTy);
57 
58  /// Produce a body for an opaque type in the dest module from a type
59  /// definition in the source module.
60  void linkDefinedTypeBodies();
61 
62  /// Return the mapped type to use for the specified input type from the
63  /// source module.
64  Type *get(Type *SrcTy);
65  Type *get(Type *SrcTy, SmallPtrSet<StructType *, 8> &Visited);
66 
67  void finishType(StructType *DTy, StructType *STy, ArrayRef<Type *> ETypes);
68 
69  FunctionType *get(FunctionType *T) {
70  return cast<FunctionType>(get((Type *)T));
71  }
72 
73 private:
74  Type *remapType(Type *SrcTy) override { return get(SrcTy); }
75 
76  bool areTypesIsomorphic(Type *DstTy, Type *SrcTy);
77 };
78 }
79 
80 void TypeMapTy::addTypeMapping(Type *DstTy, Type *SrcTy) {
81  assert(SpeculativeTypes.empty());
82  assert(SpeculativeDstOpaqueTypes.empty());
83 
84  // Check to see if these types are recursively isomorphic and establish a
85  // mapping between them if so.
86  if (!areTypesIsomorphic(DstTy, SrcTy)) {
87  // Oops, they aren't isomorphic. Just discard this request by rolling out
88  // any speculative mappings we've established.
89  for (Type *Ty : SpeculativeTypes)
90  MappedTypes.erase(Ty);
91 
92  SrcDefinitionsToResolve.resize(SrcDefinitionsToResolve.size() -
93  SpeculativeDstOpaqueTypes.size());
94  for (StructType *Ty : SpeculativeDstOpaqueTypes)
95  DstResolvedOpaqueTypes.erase(Ty);
96  } else {
97  // SrcTy and DstTy are recursively ismorphic. We clear names of SrcTy
98  // and all its descendants to lower amount of renaming in LLVM context
99  // Renaming occurs because we load all source modules to the same context
100  // and declaration with existing name gets renamed (i.e Foo -> Foo.42).
101  // As a result we may get several different types in the destination
102  // module, which are in fact the same.
103  for (Type *Ty : SpeculativeTypes)
104  if (auto *STy = dyn_cast<StructType>(Ty))
105  if (STy->hasName())
106  STy->setName("");
107  }
108  SpeculativeTypes.clear();
109  SpeculativeDstOpaqueTypes.clear();
110 }
111 
112 /// Recursively walk this pair of types, returning true if they are isomorphic,
113 /// false if they are not.
114 bool TypeMapTy::areTypesIsomorphic(Type *DstTy, Type *SrcTy) {
115  // Two types with differing kinds are clearly not isomorphic.
116  if (DstTy->getTypeID() != SrcTy->getTypeID())
117  return false;
118 
119  // If we have an entry in the MappedTypes table, then we have our answer.
120  Type *&Entry = MappedTypes[SrcTy];
121  if (Entry)
122  return Entry == DstTy;
123 
124  // Two identical types are clearly isomorphic. Remember this
125  // non-speculatively.
126  if (DstTy == SrcTy) {
127  Entry = DstTy;
128  return true;
129  }
130 
131  // Okay, we have two types with identical kinds that we haven't seen before.
132 
133  // If this is an opaque struct type, special case it.
134  if (StructType *SSTy = dyn_cast<StructType>(SrcTy)) {
135  // Mapping an opaque type to any struct, just keep the dest struct.
136  if (SSTy->isOpaque()) {
137  Entry = DstTy;
138  SpeculativeTypes.push_back(SrcTy);
139  return true;
140  }
141 
142  // Mapping a non-opaque source type to an opaque dest. If this is the first
143  // type that we're mapping onto this destination type then we succeed. Keep
144  // the dest, but fill it in later. If this is the second (different) type
145  // that we're trying to map onto the same opaque type then we fail.
146  if (cast<StructType>(DstTy)->isOpaque()) {
147  // We can only map one source type onto the opaque destination type.
148  if (!DstResolvedOpaqueTypes.insert(cast<StructType>(DstTy)).second)
149  return false;
150  SrcDefinitionsToResolve.push_back(SSTy);
151  SpeculativeTypes.push_back(SrcTy);
152  SpeculativeDstOpaqueTypes.push_back(cast<StructType>(DstTy));
153  Entry = DstTy;
154  return true;
155  }
156  }
157 
158  // If the number of subtypes disagree between the two types, then we fail.
159  if (SrcTy->getNumContainedTypes() != DstTy->getNumContainedTypes())
160  return false;
161 
162  // Fail if any of the extra properties (e.g. array size) of the type disagree.
163  if (isa<IntegerType>(DstTy))
164  return false; // bitwidth disagrees.
165  if (PointerType *PT = dyn_cast<PointerType>(DstTy)) {
166  if (PT->getAddressSpace() != cast<PointerType>(SrcTy)->getAddressSpace())
167  return false;
168  } else if (FunctionType *FT = dyn_cast<FunctionType>(DstTy)) {
169  if (FT->isVarArg() != cast<FunctionType>(SrcTy)->isVarArg())
170  return false;
171  } else if (StructType *DSTy = dyn_cast<StructType>(DstTy)) {
172  StructType *SSTy = cast<StructType>(SrcTy);
173  if (DSTy->isLiteral() != SSTy->isLiteral() ||
174  DSTy->isPacked() != SSTy->isPacked())
175  return false;
176  } else if (auto *DSeqTy = dyn_cast<SequentialType>(DstTy)) {
177  if (DSeqTy->getNumElements() !=
178  cast<SequentialType>(SrcTy)->getNumElements())
179  return false;
180  }
181 
182  // Otherwise, we speculate that these two types will line up and recursively
183  // check the subelements.
184  Entry = DstTy;
185  SpeculativeTypes.push_back(SrcTy);
186 
187  for (unsigned I = 0, E = SrcTy->getNumContainedTypes(); I != E; ++I)
188  if (!areTypesIsomorphic(DstTy->getContainedType(I),
189  SrcTy->getContainedType(I)))
190  return false;
191 
192  // If everything seems to have lined up, then everything is great.
193  return true;
194 }
195 
196 void TypeMapTy::linkDefinedTypeBodies() {
197  SmallVector<Type *, 16> Elements;
198  for (StructType *SrcSTy : SrcDefinitionsToResolve) {
199  StructType *DstSTy = cast<StructType>(MappedTypes[SrcSTy]);
200  assert(DstSTy->isOpaque());
201 
202  // Map the body of the source type over to a new body for the dest type.
203  Elements.resize(SrcSTy->getNumElements());
204  for (unsigned I = 0, E = Elements.size(); I != E; ++I)
205  Elements[I] = get(SrcSTy->getElementType(I));
206 
207  DstSTy->setBody(Elements, SrcSTy->isPacked());
208  DstStructTypesSet.switchToNonOpaque(DstSTy);
209  }
210  SrcDefinitionsToResolve.clear();
211  DstResolvedOpaqueTypes.clear();
212 }
213 
214 void TypeMapTy::finishType(StructType *DTy, StructType *STy,
215  ArrayRef<Type *> ETypes) {
216  DTy->setBody(ETypes, STy->isPacked());
217 
218  // Steal STy's name.
219  if (STy->hasName()) {
220  SmallString<16> TmpName = STy->getName();
221  STy->setName("");
222  DTy->setName(TmpName);
223  }
224 
225  DstStructTypesSet.addNonOpaque(DTy);
226 }
227 
228 Type *TypeMapTy::get(Type *Ty) {
230  return get(Ty, Visited);
231 }
232 
233 Type *TypeMapTy::get(Type *Ty, SmallPtrSet<StructType *, 8> &Visited) {
234  // If we already have an entry for this type, return it.
235  Type **Entry = &MappedTypes[Ty];
236  if (*Entry)
237  return *Entry;
238 
239  // These are types that LLVM itself will unique.
240  bool IsUniqued = !isa<StructType>(Ty) || cast<StructType>(Ty)->isLiteral();
241 
242  if (!IsUniqued) {
243  StructType *STy = cast<StructType>(Ty);
244  // This is actually a type from the destination module, this can be reached
245  // when this type is loaded in another module, added to DstStructTypesSet,
246  // and then we reach the same type in another module where it has not been
247  // added to MappedTypes. (PR37684)
248  if (STy->getContext().isODRUniquingDebugTypes() && !STy->isOpaque() &&
249  DstStructTypesSet.hasType(STy))
250  return *Entry = STy;
251 
252 #ifndef NDEBUG
253  for (auto &Pair : MappedTypes) {
254  assert(!(Pair.first != Ty && Pair.second == Ty) &&
255  "mapping to a source type");
256  }
257 #endif
258 
259  if (!Visited.insert(STy).second) {
261  return *Entry = DTy;
262  }
263  }
264 
265  // If this is not a recursive type, then just map all of the elements and
266  // then rebuild the type from inside out.
267  SmallVector<Type *, 4> ElementTypes;
268 
269  // If there are no element types to map, then the type is itself. This is
270  // true for the anonymous {} struct, things like 'float', integers, etc.
271  if (Ty->getNumContainedTypes() == 0 && IsUniqued)
272  return *Entry = Ty;
273 
274  // Remap all of the elements, keeping track of whether any of them change.
275  bool AnyChange = false;
276  ElementTypes.resize(Ty->getNumContainedTypes());
277  for (unsigned I = 0, E = Ty->getNumContainedTypes(); I != E; ++I) {
278  ElementTypes[I] = get(Ty->getContainedType(I), Visited);
279  AnyChange |= ElementTypes[I] != Ty->getContainedType(I);
280  }
281 
282  // If we found our type while recursively processing stuff, just use it.
283  Entry = &MappedTypes[Ty];
284  if (*Entry) {
285  if (auto *DTy = dyn_cast<StructType>(*Entry)) {
286  if (DTy->isOpaque()) {
287  auto *STy = cast<StructType>(Ty);
288  finishType(DTy, STy, ElementTypes);
289  }
290  }
291  return *Entry;
292  }
293 
294  // If all of the element types mapped directly over and the type is not
295  // a named struct, then the type is usable as-is.
296  if (!AnyChange && IsUniqued)
297  return *Entry = Ty;
298 
299  // Otherwise, rebuild a modified type.
300  switch (Ty->getTypeID()) {
301  default:
302  llvm_unreachable("unknown derived type to remap");
303  case Type::ArrayTyID:
304  return *Entry = ArrayType::get(ElementTypes[0],
305  cast<ArrayType>(Ty)->getNumElements());
306  case Type::VectorTyID:
307  return *Entry = VectorType::get(ElementTypes[0],
308  cast<VectorType>(Ty)->getNumElements());
309  case Type::PointerTyID:
310  return *Entry = PointerType::get(ElementTypes[0],
311  cast<PointerType>(Ty)->getAddressSpace());
312  case Type::FunctionTyID:
313  return *Entry = FunctionType::get(ElementTypes[0],
314  makeArrayRef(ElementTypes).slice(1),
315  cast<FunctionType>(Ty)->isVarArg());
316  case Type::StructTyID: {
317  auto *STy = cast<StructType>(Ty);
318  bool IsPacked = STy->isPacked();
319  if (IsUniqued)
320  return *Entry = StructType::get(Ty->getContext(), ElementTypes, IsPacked);
321 
322  // If the type is opaque, we can just use it directly.
323  if (STy->isOpaque()) {
324  DstStructTypesSet.addOpaque(STy);
325  return *Entry = Ty;
326  }
327 
328  if (StructType *OldT =
329  DstStructTypesSet.findNonOpaque(ElementTypes, IsPacked)) {
330  STy->setName("");
331  return *Entry = OldT;
332  }
333 
334  if (!AnyChange) {
335  DstStructTypesSet.addNonOpaque(STy);
336  return *Entry = Ty;
337  }
338 
340  finishType(DTy, STy, ElementTypes);
341  return *Entry = DTy;
342  }
343  }
344 }
345 
347  const Twine &Msg)
348  : DiagnosticInfo(DK_Linker, Severity), Msg(Msg) {}
349 void LinkDiagnosticInfo::print(DiagnosticPrinter &DP) const { DP << Msg; }
350 
351 //===----------------------------------------------------------------------===//
352 // IRLinker implementation.
353 //===----------------------------------------------------------------------===//
354 
355 namespace {
356 class IRLinker;
357 
358 /// Creates prototypes for functions that are lazily linked on the fly. This
359 /// speeds up linking for modules with many/ lazily linked functions of which
360 /// few get used.
361 class GlobalValueMaterializer final : public ValueMaterializer {
362  IRLinker &TheIRLinker;
363 
364 public:
365  GlobalValueMaterializer(IRLinker &TheIRLinker) : TheIRLinker(TheIRLinker) {}
366  Value *materialize(Value *V) override;
367 };
368 
369 class LocalValueMaterializer final : public ValueMaterializer {
370  IRLinker &TheIRLinker;
371 
372 public:
373  LocalValueMaterializer(IRLinker &TheIRLinker) : TheIRLinker(TheIRLinker) {}
374  Value *materialize(Value *V) override;
375 };
376 
377 /// Type of the Metadata map in \a ValueToValueMapTy.
379 
380 /// This is responsible for keeping track of the state used for moving data
381 /// from SrcM to DstM.
382 class IRLinker {
383  Module &DstM;
384  std::unique_ptr<Module> SrcM;
385 
386  /// See IRMover::move().
387  std::function<void(GlobalValue &, IRMover::ValueAdder)> AddLazyFor;
388 
389  TypeMapTy TypeMap;
390  GlobalValueMaterializer GValMaterializer;
391  LocalValueMaterializer LValMaterializer;
392 
393  /// A metadata map that's shared between IRLinker instances.
394  MDMapT &SharedMDs;
395 
396  /// Mapping of values from what they used to be in Src, to what they are now
397  /// in DstM. ValueToValueMapTy is a ValueMap, which involves some overhead
398  /// due to the use of Value handles which the Linker doesn't actually need,
399  /// but this allows us to reuse the ValueMapper code.
401  ValueToValueMapTy AliasValueMap;
402 
403  DenseSet<GlobalValue *> ValuesToLink;
404  std::vector<GlobalValue *> Worklist;
405  std::vector<std::pair<GlobalValue *, Value*>> RAUWWorklist;
406 
407  void maybeAdd(GlobalValue *GV) {
408  if (ValuesToLink.insert(GV).second)
409  Worklist.push_back(GV);
410  }
411 
412  /// Whether we are importing globals for ThinLTO, as opposed to linking the
413  /// source module. If this flag is set, it means that we can rely on some
414  /// other object file to define any non-GlobalValue entities defined by the
415  /// source module. This currently causes us to not link retained types in
416  /// debug info metadata and module inline asm.
417  bool IsPerformingImport;
418 
419  /// Set to true when all global value body linking is complete (including
420  /// lazy linking). Used to prevent metadata linking from creating new
421  /// references.
422  bool DoneLinkingBodies = false;
423 
424  /// The Error encountered during materialization. We use an Optional here to
425  /// avoid needing to manage an unconsumed success value.
426  Optional<Error> FoundError;
427  void setError(Error E) {
428  if (E)
429  FoundError = std::move(E);
430  }
431 
432  /// Most of the errors produced by this module are inconvertible StringErrors.
433  /// This convenience function lets us return one of those more easily.
434  Error stringErr(const Twine &T) {
435  return make_error<StringError>(T, inconvertibleErrorCode());
436  }
437 
438  /// Entry point for mapping values and alternate context for mapping aliases.
439  ValueMapper Mapper;
440  unsigned AliasMCID;
441 
442  /// Handles cloning of a global values from the source module into
443  /// the destination module, including setting the attributes and visibility.
444  GlobalValue *copyGlobalValueProto(const GlobalValue *SGV, bool ForDefinition);
445 
446  void emitWarning(const Twine &Message) {
447  SrcM->getContext().diagnose(LinkDiagnosticInfo(DS_Warning, Message));
448  }
449 
450  /// Given a global in the source module, return the global in the
451  /// destination module that is being linked to, if any.
452  GlobalValue *getLinkedToGlobal(const GlobalValue *SrcGV) {
453  // If the source has no name it can't link. If it has local linkage,
454  // there is no name match-up going on.
455  if (!SrcGV->hasName() || SrcGV->hasLocalLinkage())
456  return nullptr;
457 
458  // Otherwise see if we have a match in the destination module's symtab.
459  GlobalValue *DGV = DstM.getNamedValue(SrcGV->getName());
460  if (!DGV)
461  return nullptr;
462 
463  // If we found a global with the same name in the dest module, but it has
464  // internal linkage, we are really not doing any linkage here.
465  if (DGV->hasLocalLinkage())
466  return nullptr;
467 
468  // Otherwise, we do in fact link to the destination global.
469  return DGV;
470  }
471 
472  void computeTypeMapping();
473 
474  Expected<Constant *> linkAppendingVarProto(GlobalVariable *DstGV,
475  const GlobalVariable *SrcGV);
476 
477  /// Given the GlobaValue \p SGV in the source module, and the matching
478  /// GlobalValue \p DGV (if any), return true if the linker will pull \p SGV
479  /// into the destination module.
480  ///
481  /// Note this code may call the client-provided \p AddLazyFor.
482  bool shouldLink(GlobalValue *DGV, GlobalValue &SGV);
483  Expected<Constant *> linkGlobalValueProto(GlobalValue *GV, bool ForAlias);
484 
485  Error linkModuleFlagsMetadata();
486 
487  void linkGlobalVariable(GlobalVariable &Dst, GlobalVariable &Src);
488  Error linkFunctionBody(Function &Dst, Function &Src);
489  void linkAliasBody(GlobalAlias &Dst, GlobalAlias &Src);
490  Error linkGlobalValueBody(GlobalValue &Dst, GlobalValue &Src);
491 
492  /// Functions that take care of cloning a specific global value type
493  /// into the destination module.
494  GlobalVariable *copyGlobalVariableProto(const GlobalVariable *SGVar);
495  Function *copyFunctionProto(const Function *SF);
496  GlobalValue *copyGlobalAliasProto(const GlobalAlias *SGA);
497 
498  /// Perform "replace all uses with" operations. These work items need to be
499  /// performed as part of materialization, but we postpone them to happen after
500  /// materialization is done. The materializer called by ValueMapper is not
501  /// expected to delete constants, as ValueMapper is holding pointers to some
502  /// of them, but constant destruction may be indirectly triggered by RAUW.
503  /// Hence, the need to move this out of the materialization call chain.
504  void flushRAUWWorklist();
505 
506  /// When importing for ThinLTO, prevent importing of types listed on
507  /// the DICompileUnit that we don't need a copy of in the importing
508  /// module.
509  void prepareCompileUnitsForImport();
510  void linkNamedMDNodes();
511 
512 public:
513  IRLinker(Module &DstM, MDMapT &SharedMDs,
514  IRMover::IdentifiedStructTypeSet &Set, std::unique_ptr<Module> SrcM,
515  ArrayRef<GlobalValue *> ValuesToLink,
516  std::function<void(GlobalValue &, IRMover::ValueAdder)> AddLazyFor,
517  bool IsPerformingImport)
518  : DstM(DstM), SrcM(std::move(SrcM)), AddLazyFor(std::move(AddLazyFor)),
519  TypeMap(Set), GValMaterializer(*this), LValMaterializer(*this),
520  SharedMDs(SharedMDs), IsPerformingImport(IsPerformingImport),
521  Mapper(ValueMap, RF_MoveDistinctMDs | RF_IgnoreMissingLocals, &TypeMap,
522  &GValMaterializer),
523  AliasMCID(Mapper.registerAlternateMappingContext(AliasValueMap,
524  &LValMaterializer)) {
525  ValueMap.getMDMap() = std::move(SharedMDs);
526  for (GlobalValue *GV : ValuesToLink)
527  maybeAdd(GV);
528  if (IsPerformingImport)
529  prepareCompileUnitsForImport();
530  }
531  ~IRLinker() { SharedMDs = std::move(*ValueMap.getMDMap()); }
532 
533  Error run();
534  Value *materialize(Value *V, bool ForAlias);
535 };
536 }
537 
538 /// The LLVM SymbolTable class autorenames globals that conflict in the symbol
539 /// table. This is good for all clients except for us. Go through the trouble
540 /// to force this back.
542  // If the global doesn't force its name or if it already has the right name,
543  // there is nothing for us to do.
544  if (GV->hasLocalLinkage() || GV->getName() == Name)
545  return;
546 
547  Module *M = GV->getParent();
548 
549  // If there is a conflict, rename the conflict.
550  if (GlobalValue *ConflictGV = M->getNamedValue(Name)) {
551  GV->takeName(ConflictGV);
552  ConflictGV->setName(Name); // This will cause ConflictGV to get renamed
553  assert(ConflictGV->getName() != Name && "forceRenaming didn't work");
554  } else {
555  GV->setName(Name); // Force the name back
556  }
557 }
558 
559 Value *GlobalValueMaterializer::materialize(Value *SGV) {
560  return TheIRLinker.materialize(SGV, false);
561 }
562 
563 Value *LocalValueMaterializer::materialize(Value *SGV) {
564  return TheIRLinker.materialize(SGV, true);
565 }
566 
567 Value *IRLinker::materialize(Value *V, bool ForAlias) {
568  auto *SGV = dyn_cast<GlobalValue>(V);
569  if (!SGV)
570  return nullptr;
571 
572  Expected<Constant *> NewProto = linkGlobalValueProto(SGV, ForAlias);
573  if (!NewProto) {
574  setError(NewProto.takeError());
575  return nullptr;
576  }
577  if (!*NewProto)
578  return nullptr;
579 
580  GlobalValue *New = dyn_cast<GlobalValue>(*NewProto);
581  if (!New)
582  return *NewProto;
583 
584  // If we already created the body, just return.
585  if (auto *F = dyn_cast<Function>(New)) {
586  if (!F->isDeclaration())
587  return New;
588  } else if (auto *V = dyn_cast<GlobalVariable>(New)) {
589  if (V->hasInitializer() || V->hasAppendingLinkage())
590  return New;
591  } else {
592  auto *A = cast<GlobalAlias>(New);
593  if (A->getAliasee())
594  return New;
595  }
596 
597  // When linking a global for an alias, it will always be linked. However we
598  // need to check if it was not already scheduled to satisfy a reference from a
599  // regular global value initializer. We know if it has been schedule if the
600  // "New" GlobalValue that is mapped here for the alias is the same as the one
601  // already mapped. If there is an entry in the ValueMap but the value is
602  // different, it means that the value already had a definition in the
603  // destination module (linkonce for instance), but we need a new definition
604  // for the alias ("New" will be different.
605  if (ForAlias && ValueMap.lookup(SGV) == New)
606  return New;
607 
608  if (ForAlias || shouldLink(New, *SGV))
609  setError(linkGlobalValueBody(*New, *SGV));
610 
611  return New;
612 }
613 
614 /// Loop through the global variables in the src module and merge them into the
615 /// dest module.
616 GlobalVariable *IRLinker::copyGlobalVariableProto(const GlobalVariable *SGVar) {
617  // No linking to be performed or linking from the source: simply create an
618  // identical version of the symbol over in the dest module... the
619  // initializer will be filled in later by LinkGlobalInits.
620  GlobalVariable *NewDGV =
621  new GlobalVariable(DstM, TypeMap.get(SGVar->getValueType()),
623  /*init*/ nullptr, SGVar->getName(),
624  /*insertbefore*/ nullptr, SGVar->getThreadLocalMode(),
625  SGVar->getType()->getAddressSpace());
626  NewDGV->setAlignment(SGVar->getAlignment());
627  NewDGV->copyAttributesFrom(SGVar);
628  return NewDGV;
629 }
630 
631 /// Link the function in the source module into the destination module if
632 /// needed, setting up mapping information.
633 Function *IRLinker::copyFunctionProto(const Function *SF) {
634  // If there is no linkage to be performed or we are linking from the source,
635  // bring SF over.
636  auto *F =
637  Function::Create(TypeMap.get(SF->getFunctionType()),
638  GlobalValue::ExternalLinkage, SF->getName(), &DstM);
639  F->copyAttributesFrom(SF);
640  return F;
641 }
642 
643 /// Set up prototypes for any aliases that come over from the source module.
644 GlobalValue *IRLinker::copyGlobalAliasProto(const GlobalAlias *SGA) {
645  // If there is no linkage to be performed or we're linking from the source,
646  // bring over SGA.
647  auto *Ty = TypeMap.get(SGA->getValueType());
648  auto *GA =
650  GlobalValue::ExternalLinkage, SGA->getName(), &DstM);
651  GA->copyAttributesFrom(SGA);
652  return GA;
653 }
654 
655 GlobalValue *IRLinker::copyGlobalValueProto(const GlobalValue *SGV,
656  bool ForDefinition) {
657  GlobalValue *NewGV;
658  if (auto *SGVar = dyn_cast<GlobalVariable>(SGV)) {
659  NewGV = copyGlobalVariableProto(SGVar);
660  } else if (auto *SF = dyn_cast<Function>(SGV)) {
661  NewGV = copyFunctionProto(SF);
662  } else {
663  if (ForDefinition)
664  NewGV = copyGlobalAliasProto(cast<GlobalAlias>(SGV));
665  else if (SGV->getValueType()->isFunctionTy())
666  NewGV =
667  Function::Create(cast<FunctionType>(TypeMap.get(SGV->getValueType())),
668  GlobalValue::ExternalLinkage, SGV->getName(), &DstM);
669  else
670  NewGV = new GlobalVariable(
671  DstM, TypeMap.get(SGV->getValueType()),
672  /*isConstant*/ false, GlobalValue::ExternalLinkage,
673  /*init*/ nullptr, SGV->getName(),
674  /*insertbefore*/ nullptr, SGV->getThreadLocalMode(),
675  SGV->getType()->getAddressSpace());
676  }
677 
678  if (ForDefinition)
679  NewGV->setLinkage(SGV->getLinkage());
680  else if (SGV->hasExternalWeakLinkage())
682 
683  if (auto *NewGO = dyn_cast<GlobalObject>(NewGV)) {
684  // Metadata for global variables and function declarations is copied eagerly.
685  if (isa<GlobalVariable>(SGV) || SGV->isDeclaration())
686  NewGO->copyMetadata(cast<GlobalObject>(SGV), 0);
687  }
688 
689  // Remove these copied constants in case this stays a declaration, since
690  // they point to the source module. If the def is linked the values will
691  // be mapped in during linkFunctionBody.
692  if (auto *NewF = dyn_cast<Function>(NewGV)) {
693  NewF->setPersonalityFn(nullptr);
694  NewF->setPrefixData(nullptr);
695  NewF->setPrologueData(nullptr);
696  }
697 
698  return NewGV;
699 }
700 
702  size_t DotPos = Name.rfind('.');
703  return (DotPos == 0 || DotPos == StringRef::npos || Name.back() == '.' ||
704  !isdigit(static_cast<unsigned char>(Name[DotPos + 1])))
705  ? Name
706  : Name.substr(0, DotPos);
707 }
708 
709 /// Loop over all of the linked values to compute type mappings. For example,
710 /// if we link "extern Foo *x" and "Foo *x = NULL", then we have two struct
711 /// types 'Foo' but one got renamed when the module was loaded into the same
712 /// LLVMContext.
713 void IRLinker::computeTypeMapping() {
714  for (GlobalValue &SGV : SrcM->globals()) {
715  GlobalValue *DGV = getLinkedToGlobal(&SGV);
716  if (!DGV)
717  continue;
718 
719  if (!DGV->hasAppendingLinkage() || !SGV.hasAppendingLinkage()) {
720  TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
721  continue;
722  }
723 
724  // Unify the element type of appending arrays.
725  ArrayType *DAT = cast<ArrayType>(DGV->getValueType());
726  ArrayType *SAT = cast<ArrayType>(SGV.getValueType());
727  TypeMap.addTypeMapping(DAT->getElementType(), SAT->getElementType());
728  }
729 
730  for (GlobalValue &SGV : *SrcM)
731  if (GlobalValue *DGV = getLinkedToGlobal(&SGV))
732  TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
733 
734  for (GlobalValue &SGV : SrcM->aliases())
735  if (GlobalValue *DGV = getLinkedToGlobal(&SGV))
736  TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
737 
738  // Incorporate types by name, scanning all the types in the source module.
739  // At this point, the destination module may have a type "%foo = { i32 }" for
740  // example. When the source module got loaded into the same LLVMContext, if
741  // it had the same type, it would have been renamed to "%foo.42 = { i32 }".
742  std::vector<StructType *> Types = SrcM->getIdentifiedStructTypes();
743  for (StructType *ST : Types) {
744  if (!ST->hasName())
745  continue;
746 
747  if (TypeMap.DstStructTypesSet.hasType(ST)) {
748  // This is actually a type from the destination module.
749  // getIdentifiedStructTypes() can have found it by walking debug info
750  // metadata nodes, some of which get linked by name when ODR Type Uniquing
751  // is enabled on the Context, from the source to the destination module.
752  continue;
753  }
754 
755  auto STTypePrefix = getTypeNamePrefix(ST->getName());
756  if (STTypePrefix.size()== ST->getName().size())
757  continue;
758 
759  // Check to see if the destination module has a struct with the prefix name.
760  StructType *DST = DstM.getTypeByName(STTypePrefix);
761  if (!DST)
762  continue;
763 
764  // Don't use it if this actually came from the source module. They're in
765  // the same LLVMContext after all. Also don't use it unless the type is
766  // actually used in the destination module. This can happen in situations
767  // like this:
768  //
769  // Module A Module B
770  // -------- --------
771  // %Z = type { %A } %B = type { %C.1 }
772  // %A = type { %B.1, [7 x i8] } %C.1 = type { i8* }
773  // %B.1 = type { %C } %A.2 = type { %B.3, [5 x i8] }
774  // %C = type { i8* } %B.3 = type { %C.1 }
775  //
776  // When we link Module B with Module A, the '%B' in Module B is
777  // used. However, that would then use '%C.1'. But when we process '%C.1',
778  // we prefer to take the '%C' version. So we are then left with both
779  // '%C.1' and '%C' being used for the same types. This leads to some
780  // variables using one type and some using the other.
781  if (TypeMap.DstStructTypesSet.hasType(DST))
782  TypeMap.addTypeMapping(DST, ST);
783  }
784 
785  // Now that we have discovered all of the type equivalences, get a body for
786  // any 'opaque' types in the dest module that are now resolved.
787  TypeMap.linkDefinedTypeBodies();
788 }
789 
790 static void getArrayElements(const Constant *C,
792  unsigned NumElements = cast<ArrayType>(C->getType())->getNumElements();
793 
794  for (unsigned i = 0; i != NumElements; ++i)
795  Dest.push_back(C->getAggregateElement(i));
796 }
797 
798 /// If there were any appending global variables, link them together now.
800 IRLinker::linkAppendingVarProto(GlobalVariable *DstGV,
801  const GlobalVariable *SrcGV) {
802  Type *EltTy = cast<ArrayType>(TypeMap.get(SrcGV->getValueType()))
803  ->getElementType();
804 
805  // FIXME: This upgrade is done during linking to support the C API. Once the
806  // old form is deprecated, we should move this upgrade to
807  // llvm::UpgradeGlobalVariable() and simplify the logic here and in
808  // Mapper::mapAppendingVariable() in ValueMapper.cpp.
809  StringRef Name = SrcGV->getName();
810  bool IsNewStructor = false;
811  bool IsOldStructor = false;
812  if (Name == "llvm.global_ctors" || Name == "llvm.global_dtors") {
813  if (cast<StructType>(EltTy)->getNumElements() == 3)
814  IsNewStructor = true;
815  else
816  IsOldStructor = true;
817  }
818 
819  PointerType *VoidPtrTy = Type::getInt8Ty(SrcGV->getContext())->getPointerTo();
820  if (IsOldStructor) {
821  auto &ST = *cast<StructType>(EltTy);
822  Type *Tys[3] = {ST.getElementType(0), ST.getElementType(1), VoidPtrTy};
823  EltTy = StructType::get(SrcGV->getContext(), Tys, false);
824  }
825 
826  uint64_t DstNumElements = 0;
827  if (DstGV) {
828  ArrayType *DstTy = cast<ArrayType>(DstGV->getValueType());
829  DstNumElements = DstTy->getNumElements();
830 
831  if (!SrcGV->hasAppendingLinkage() || !DstGV->hasAppendingLinkage())
832  return stringErr(
833  "Linking globals named '" + SrcGV->getName() +
834  "': can only link appending global with another appending "
835  "global!");
836 
837  // Check to see that they two arrays agree on type.
838  if (EltTy != DstTy->getElementType())
839  return stringErr("Appending variables with different element types!");
840  if (DstGV->isConstant() != SrcGV->isConstant())
841  return stringErr("Appending variables linked with different const'ness!");
842 
843  if (DstGV->getAlignment() != SrcGV->getAlignment())
844  return stringErr(
845  "Appending variables with different alignment need to be linked!");
846 
847  if (DstGV->getVisibility() != SrcGV->getVisibility())
848  return stringErr(
849  "Appending variables with different visibility need to be linked!");
850 
851  if (DstGV->hasGlobalUnnamedAddr() != SrcGV->hasGlobalUnnamedAddr())
852  return stringErr(
853  "Appending variables with different unnamed_addr need to be linked!");
854 
855  if (DstGV->getSection() != SrcGV->getSection())
856  return stringErr(
857  "Appending variables with different section name need to be linked!");
858  }
859 
860  SmallVector<Constant *, 16> SrcElements;
861  getArrayElements(SrcGV->getInitializer(), SrcElements);
862 
863  if (IsNewStructor) {
864  auto It = remove_if(SrcElements, [this](Constant *E) {
865  auto *Key =
867  if (!Key)
868  return false;
869  GlobalValue *DGV = getLinkedToGlobal(Key);
870  return !shouldLink(DGV, *Key);
871  });
872  SrcElements.erase(It, SrcElements.end());
873  }
874  uint64_t NewSize = DstNumElements + SrcElements.size();
875  ArrayType *NewType = ArrayType::get(EltTy, NewSize);
876 
877  // Create the new global variable.
878  GlobalVariable *NG = new GlobalVariable(
879  DstM, NewType, SrcGV->isConstant(), SrcGV->getLinkage(),
880  /*init*/ nullptr, /*name*/ "", DstGV, SrcGV->getThreadLocalMode(),
881  SrcGV->getType()->getAddressSpace());
882 
883  NG->copyAttributesFrom(SrcGV);
884  forceRenaming(NG, SrcGV->getName());
885 
886  Constant *Ret = ConstantExpr::getBitCast(NG, TypeMap.get(SrcGV->getType()));
887 
888  Mapper.scheduleMapAppendingVariable(*NG,
889  DstGV ? DstGV->getInitializer() : nullptr,
890  IsOldStructor, SrcElements);
891 
892  // Replace any uses of the two global variables with uses of the new
893  // global.
894  if (DstGV) {
895  RAUWWorklist.push_back(
896  std::make_pair(DstGV, ConstantExpr::getBitCast(NG, DstGV->getType())));
897  }
898 
899  return Ret;
900 }
901 
902 bool IRLinker::shouldLink(GlobalValue *DGV, GlobalValue &SGV) {
903  if (ValuesToLink.count(&SGV) || SGV.hasLocalLinkage())
904  return true;
905 
906  if (DGV && !DGV->isDeclarationForLinker())
907  return false;
908 
909  if (SGV.isDeclaration() || DoneLinkingBodies)
910  return false;
911 
912  // Callback to the client to give a chance to lazily add the Global to the
913  // list of value to link.
914  bool LazilyAdded = false;
915  AddLazyFor(SGV, [this, &LazilyAdded](GlobalValue &GV) {
916  maybeAdd(&GV);
917  LazilyAdded = true;
918  });
919  return LazilyAdded;
920 }
921 
922 Expected<Constant *> IRLinker::linkGlobalValueProto(GlobalValue *SGV,
923  bool ForAlias) {
924  GlobalValue *DGV = getLinkedToGlobal(SGV);
925 
926  bool ShouldLink = shouldLink(DGV, *SGV);
927 
928  // just missing from map
929  if (ShouldLink) {
930  auto I = ValueMap.find(SGV);
931  if (I != ValueMap.end())
932  return cast<Constant>(I->second);
933 
934  I = AliasValueMap.find(SGV);
935  if (I != AliasValueMap.end())
936  return cast<Constant>(I->second);
937  }
938 
939  if (!ShouldLink && ForAlias)
940  DGV = nullptr;
941 
942  // Handle the ultra special appending linkage case first.
943  assert(!DGV || SGV->hasAppendingLinkage() == DGV->hasAppendingLinkage());
944  if (SGV->hasAppendingLinkage())
945  return linkAppendingVarProto(cast_or_null<GlobalVariable>(DGV),
946  cast<GlobalVariable>(SGV));
947 
948  GlobalValue *NewGV;
949  if (DGV && !ShouldLink) {
950  NewGV = DGV;
951  } else {
952  // If we are done linking global value bodies (i.e. we are performing
953  // metadata linking), don't link in the global value due to this
954  // reference, simply map it to null.
955  if (DoneLinkingBodies)
956  return nullptr;
957 
958  NewGV = copyGlobalValueProto(SGV, ShouldLink || ForAlias);
959  if (ShouldLink || !ForAlias)
960  forceRenaming(NewGV, SGV->getName());
961  }
962 
963  // Overloaded intrinsics have overloaded types names as part of their
964  // names. If we renamed overloaded types we should rename the intrinsic
965  // as well.
966  if (Function *F = dyn_cast<Function>(NewGV))
967  if (auto Remangled = Intrinsic::remangleIntrinsicFunction(F))
968  NewGV = Remangled.getValue();
969 
970  if (ShouldLink || ForAlias) {
971  if (const Comdat *SC = SGV->getComdat()) {
972  if (auto *GO = dyn_cast<GlobalObject>(NewGV)) {
973  Comdat *DC = DstM.getOrInsertComdat(SC->getName());
974  DC->setSelectionKind(SC->getSelectionKind());
975  GO->setComdat(DC);
976  }
977  }
978  }
979 
980  if (!ShouldLink && ForAlias)
982 
983  Constant *C = NewGV;
984  // Only create a bitcast if necessary. In particular, with
985  // DebugTypeODRUniquing we may reach metadata in the destination module
986  // containing a GV from the source module, in which case SGV will be
987  // the same as DGV and NewGV, and TypeMap.get() will assert since it
988  // assumes it is being invoked on a type in the source module.
989  if (DGV && NewGV != SGV) {
991  NewGV, TypeMap.get(SGV->getType()));
992  }
993 
994  if (DGV && NewGV != DGV) {
995  // Schedule "replace all uses with" to happen after materializing is
996  // done. It is not safe to do it now, since ValueMapper may be holding
997  // pointers to constants that will get deleted if RAUW runs.
998  RAUWWorklist.push_back(std::make_pair(
999  DGV,
1001  }
1002 
1003  return C;
1004 }
1005 
1006 /// Update the initializers in the Dest module now that all globals that may be
1007 /// referenced are in Dest.
1008 void IRLinker::linkGlobalVariable(GlobalVariable &Dst, GlobalVariable &Src) {
1009  // Figure out what the initializer looks like in the dest module.
1010  Mapper.scheduleMapGlobalInitializer(Dst, *Src.getInitializer());
1011 }
1012 
1013 /// Copy the source function over into the dest function and fix up references
1014 /// to values. At this point we know that Dest is an external function, and
1015 /// that Src is not.
1016 Error IRLinker::linkFunctionBody(Function &Dst, Function &Src) {
1017  assert(Dst.isDeclaration() && !Src.isDeclaration());
1018 
1019  // Materialize if needed.
1020  if (Error Err = Src.materialize())
1021  return Err;
1022 
1023  // Link in the operands without remapping.
1024  if (Src.hasPrefixData())
1025  Dst.setPrefixData(Src.getPrefixData());
1026  if (Src.hasPrologueData())
1027  Dst.setPrologueData(Src.getPrologueData());
1028  if (Src.hasPersonalityFn())
1030 
1031  // Copy over the metadata attachments without remapping.
1032  Dst.copyMetadata(&Src, 0);
1033 
1034  // Steal arguments and splice the body of Src into Dst.
1035  Dst.stealArgumentListFrom(Src);
1036  Dst.getBasicBlockList().splice(Dst.end(), Src.getBasicBlockList());
1037 
1038  // Everything has been moved over. Remap it.
1039  Mapper.scheduleRemapFunction(Dst);
1040  return Error::success();
1041 }
1042 
1043 void IRLinker::linkAliasBody(GlobalAlias &Dst, GlobalAlias &Src) {
1044  Mapper.scheduleMapGlobalAliasee(Dst, *Src.getAliasee(), AliasMCID);
1045 }
1046 
1047 Error IRLinker::linkGlobalValueBody(GlobalValue &Dst, GlobalValue &Src) {
1048  if (auto *F = dyn_cast<Function>(&Src))
1049  return linkFunctionBody(cast<Function>(Dst), *F);
1050  if (auto *GVar = dyn_cast<GlobalVariable>(&Src)) {
1051  linkGlobalVariable(cast<GlobalVariable>(Dst), *GVar);
1052  return Error::success();
1053  }
1054  linkAliasBody(cast<GlobalAlias>(Dst), cast<GlobalAlias>(Src));
1055  return Error::success();
1056 }
1057 
1058 void IRLinker::flushRAUWWorklist() {
1059  for (const auto Elem : RAUWWorklist) {
1060  GlobalValue *Old;
1061  Value *New;
1062  std::tie(Old, New) = Elem;
1063 
1064  Old->replaceAllUsesWith(New);
1065  Old->eraseFromParent();
1066  }
1067  RAUWWorklist.clear();
1068 }
1069 
1070 void IRLinker::prepareCompileUnitsForImport() {
1071  NamedMDNode *SrcCompileUnits = SrcM->getNamedMetadata("llvm.dbg.cu");
1072  if (!SrcCompileUnits)
1073  return;
1074  // When importing for ThinLTO, prevent importing of types listed on
1075  // the DICompileUnit that we don't need a copy of in the importing
1076  // module. They will be emitted by the originating module.
1077  for (unsigned I = 0, E = SrcCompileUnits->getNumOperands(); I != E; ++I) {
1078  auto *CU = cast<DICompileUnit>(SrcCompileUnits->getOperand(I));
1079  assert(CU && "Expected valid compile unit");
1080  // Enums, macros, and retained types don't need to be listed on the
1081  // imported DICompileUnit. This means they will only be imported
1082  // if reached from the mapped IR. Do this by setting their value map
1083  // entries to nullptr, which will automatically prevent their importing
1084  // when reached from the DICompileUnit during metadata mapping.
1085  ValueMap.MD()[CU->getRawEnumTypes()].reset(nullptr);
1086  ValueMap.MD()[CU->getRawMacros()].reset(nullptr);
1087  ValueMap.MD()[CU->getRawRetainedTypes()].reset(nullptr);
1088  // The original definition (or at least its debug info - if the variable is
1089  // internalized an optimized away) will remain in the source module, so
1090  // there's no need to import them.
1091  // If LLVM ever does more advanced optimizations on global variables
1092  // (removing/localizing write operations, for instance) that can track
1093  // through debug info, this decision may need to be revisited - but do so
1094  // with care when it comes to debug info size. Emitting small CUs containing
1095  // only a few imported entities into every destination module may be very
1096  // size inefficient.
1097  ValueMap.MD()[CU->getRawGlobalVariables()].reset(nullptr);
1098 
1099  // Imported entities only need to be mapped in if they have local
1100  // scope, as those might correspond to an imported entity inside a
1101  // function being imported (any locally scoped imported entities that
1102  // don't end up referenced by an imported function will not be emitted
1103  // into the object). Imported entities not in a local scope
1104  // (e.g. on the namespace) only need to be emitted by the originating
1105  // module. Create a list of the locally scoped imported entities, and
1106  // replace the source CUs imported entity list with the new list, so
1107  // only those are mapped in.
1108  // FIXME: Locally-scoped imported entities could be moved to the
1109  // functions they are local to instead of listing them on the CU, and
1110  // we would naturally only link in those needed by function importing.
1111  SmallVector<TrackingMDNodeRef, 4> AllImportedModules;
1112  bool ReplaceImportedEntities = false;
1113  for (auto *IE : CU->getImportedEntities()) {
1114  DIScope *Scope = IE->getScope();
1115  assert(Scope && "Invalid Scope encoding!");
1116  if (isa<DILocalScope>(Scope))
1117  AllImportedModules.emplace_back(IE);
1118  else
1119  ReplaceImportedEntities = true;
1120  }
1121  if (ReplaceImportedEntities) {
1122  if (!AllImportedModules.empty())
1123  CU->replaceImportedEntities(MDTuple::get(
1124  CU->getContext(),
1125  SmallVector<Metadata *, 16>(AllImportedModules.begin(),
1126  AllImportedModules.end())));
1127  else
1128  // If there were no local scope imported entities, we can map
1129  // the whole list to nullptr.
1130  ValueMap.MD()[CU->getRawImportedEntities()].reset(nullptr);
1131  }
1132  }
1133 }
1134 
1135 /// Insert all of the named MDNodes in Src into the Dest module.
1136 void IRLinker::linkNamedMDNodes() {
1137  const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
1138  for (const NamedMDNode &NMD : SrcM->named_metadata()) {
1139  // Don't link module flags here. Do them separately.
1140  if (&NMD == SrcModFlags)
1141  continue;
1142  NamedMDNode *DestNMD = DstM.getOrInsertNamedMetadata(NMD.getName());
1143  // Add Src elements into Dest node.
1144  for (const MDNode *Op : NMD.operands())
1145  DestNMD->addOperand(Mapper.mapMDNode(*Op));
1146  }
1147 }
1148 
1149 /// Merge the linker flags in Src into the Dest module.
1150 Error IRLinker::linkModuleFlagsMetadata() {
1151  // If the source module has no module flags, we are done.
1152  const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
1153  if (!SrcModFlags)
1154  return Error::success();
1155 
1156  // If the destination module doesn't have module flags yet, then just copy
1157  // over the source module's flags.
1158  NamedMDNode *DstModFlags = DstM.getOrInsertModuleFlagsMetadata();
1159  if (DstModFlags->getNumOperands() == 0) {
1160  for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I)
1161  DstModFlags->addOperand(SrcModFlags->getOperand(I));
1162 
1163  return Error::success();
1164  }
1165 
1166  // First build a map of the existing module flags and requirements.
1168  SmallSetVector<MDNode *, 16> Requirements;
1169  for (unsigned I = 0, E = DstModFlags->getNumOperands(); I != E; ++I) {
1170  MDNode *Op = DstModFlags->getOperand(I);
1171  ConstantInt *Behavior = mdconst::extract<ConstantInt>(Op->getOperand(0));
1172  MDString *ID = cast<MDString>(Op->getOperand(1));
1173 
1174  if (Behavior->getZExtValue() == Module::Require) {
1175  Requirements.insert(cast<MDNode>(Op->getOperand(2)));
1176  } else {
1177  Flags[ID] = std::make_pair(Op, I);
1178  }
1179  }
1180 
1181  // Merge in the flags from the source module, and also collect its set of
1182  // requirements.
1183  for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I) {
1184  MDNode *SrcOp = SrcModFlags->getOperand(I);
1185  ConstantInt *SrcBehavior =
1186  mdconst::extract<ConstantInt>(SrcOp->getOperand(0));
1187  MDString *ID = cast<MDString>(SrcOp->getOperand(1));
1188  MDNode *DstOp;
1189  unsigned DstIndex;
1190  std::tie(DstOp, DstIndex) = Flags.lookup(ID);
1191  unsigned SrcBehaviorValue = SrcBehavior->getZExtValue();
1192 
1193  // If this is a requirement, add it and continue.
1194  if (SrcBehaviorValue == Module::Require) {
1195  // If the destination module does not already have this requirement, add
1196  // it.
1197  if (Requirements.insert(cast<MDNode>(SrcOp->getOperand(2)))) {
1198  DstModFlags->addOperand(SrcOp);
1199  }
1200  continue;
1201  }
1202 
1203  // If there is no existing flag with this ID, just add it.
1204  if (!DstOp) {
1205  Flags[ID] = std::make_pair(SrcOp, DstModFlags->getNumOperands());
1206  DstModFlags->addOperand(SrcOp);
1207  continue;
1208  }
1209 
1210  // Otherwise, perform a merge.
1211  ConstantInt *DstBehavior =
1212  mdconst::extract<ConstantInt>(DstOp->getOperand(0));
1213  unsigned DstBehaviorValue = DstBehavior->getZExtValue();
1214 
1215  auto overrideDstValue = [&]() {
1216  DstModFlags->setOperand(DstIndex, SrcOp);
1217  Flags[ID].first = SrcOp;
1218  };
1219 
1220  // If either flag has override behavior, handle it first.
1221  if (DstBehaviorValue == Module::Override) {
1222  // Diagnose inconsistent flags which both have override behavior.
1223  if (SrcBehaviorValue == Module::Override &&
1224  SrcOp->getOperand(2) != DstOp->getOperand(2))
1225  return stringErr("linking module flags '" + ID->getString() +
1226  "': IDs have conflicting override values in '" +
1227  SrcM->getModuleIdentifier() + "' and '" +
1228  DstM.getModuleIdentifier() + "'");
1229  continue;
1230  } else if (SrcBehaviorValue == Module::Override) {
1231  // Update the destination flag to that of the source.
1232  overrideDstValue();
1233  continue;
1234  }
1235 
1236  // Diagnose inconsistent merge behavior types.
1237  if (SrcBehaviorValue != DstBehaviorValue)
1238  return stringErr("linking module flags '" + ID->getString() +
1239  "': IDs have conflicting behaviors in '" +
1240  SrcM->getModuleIdentifier() + "' and '" +
1241  DstM.getModuleIdentifier() + "'");
1242 
1243  auto replaceDstValue = [&](MDNode *New) {
1244  Metadata *FlagOps[] = {DstOp->getOperand(0), ID, New};
1245  MDNode *Flag = MDNode::get(DstM.getContext(), FlagOps);
1246  DstModFlags->setOperand(DstIndex, Flag);
1247  Flags[ID].first = Flag;
1248  };
1249 
1250  // Perform the merge for standard behavior types.
1251  switch (SrcBehaviorValue) {
1252  case Module::Require:
1253  case Module::Override:
1254  llvm_unreachable("not possible");
1255  case Module::Error: {
1256  // Emit an error if the values differ.
1257  if (SrcOp->getOperand(2) != DstOp->getOperand(2))
1258  return stringErr("linking module flags '" + ID->getString() +
1259  "': IDs have conflicting values in '" +
1260  SrcM->getModuleIdentifier() + "' and '" +
1261  DstM.getModuleIdentifier() + "'");
1262  continue;
1263  }
1264  case Module::Warning: {
1265  // Emit a warning if the values differ.
1266  if (SrcOp->getOperand(2) != DstOp->getOperand(2)) {
1267  std::string str;
1268  raw_string_ostream(str)
1269  << "linking module flags '" << ID->getString()
1270  << "': IDs have conflicting values ('" << *SrcOp->getOperand(2)
1271  << "' from " << SrcM->getModuleIdentifier() << " with '"
1272  << *DstOp->getOperand(2) << "' from " << DstM.getModuleIdentifier()
1273  << ')';
1274  emitWarning(str);
1275  }
1276  continue;
1277  }
1278  case Module::Max: {
1279  ConstantInt *DstValue =
1280  mdconst::extract<ConstantInt>(DstOp->getOperand(2));
1281  ConstantInt *SrcValue =
1282  mdconst::extract<ConstantInt>(SrcOp->getOperand(2));
1283  if (SrcValue->getZExtValue() > DstValue->getZExtValue())
1284  overrideDstValue();
1285  break;
1286  }
1287  case Module::Append: {
1288  MDNode *DstValue = cast<MDNode>(DstOp->getOperand(2));
1289  MDNode *SrcValue = cast<MDNode>(SrcOp->getOperand(2));
1291  MDs.reserve(DstValue->getNumOperands() + SrcValue->getNumOperands());
1292  MDs.append(DstValue->op_begin(), DstValue->op_end());
1293  MDs.append(SrcValue->op_begin(), SrcValue->op_end());
1294 
1295  replaceDstValue(MDNode::get(DstM.getContext(), MDs));
1296  break;
1297  }
1298  case Module::AppendUnique: {
1300  MDNode *DstValue = cast<MDNode>(DstOp->getOperand(2));
1301  MDNode *SrcValue = cast<MDNode>(SrcOp->getOperand(2));
1302  Elts.insert(DstValue->op_begin(), DstValue->op_end());
1303  Elts.insert(SrcValue->op_begin(), SrcValue->op_end());
1304 
1305  replaceDstValue(MDNode::get(DstM.getContext(),
1306  makeArrayRef(Elts.begin(), Elts.end())));
1307  break;
1308  }
1309  }
1310  }
1311 
1312  // Check all of the requirements.
1313  for (unsigned I = 0, E = Requirements.size(); I != E; ++I) {
1314  MDNode *Requirement = Requirements[I];
1315  MDString *Flag = cast<MDString>(Requirement->getOperand(0));
1316  Metadata *ReqValue = Requirement->getOperand(1);
1317 
1318  MDNode *Op = Flags[Flag].first;
1319  if (!Op || Op->getOperand(2) != ReqValue)
1320  return stringErr("linking module flags '" + Flag->getString() +
1321  "': does not have the required value");
1322  }
1323  return Error::success();
1324 }
1325 
1326 /// Return InlineAsm adjusted with target-specific directives if required.
1327 /// For ARM and Thumb, we have to add directives to select the appropriate ISA
1328 /// to support mixing module-level inline assembly from ARM and Thumb modules.
1329 static std::string adjustInlineAsm(const std::string &InlineAsm,
1330  const Triple &Triple) {
1331  if (Triple.getArch() == Triple::thumb || Triple.getArch() == Triple::thumbeb)
1332  return ".text\n.balign 2\n.thumb\n" + InlineAsm;
1333  if (Triple.getArch() == Triple::arm || Triple.getArch() == Triple::armeb)
1334  return ".text\n.balign 4\n.arm\n" + InlineAsm;
1335  return InlineAsm;
1336 }
1337 
1338 Error IRLinker::run() {
1339  // Ensure metadata materialized before value mapping.
1340  if (SrcM->getMaterializer())
1341  if (Error Err = SrcM->getMaterializer()->materializeMetadata())
1342  return Err;
1343 
1344  // Inherit the target data from the source module if the destination module
1345  // doesn't have one already.
1346  if (DstM.getDataLayout().isDefault())
1347  DstM.setDataLayout(SrcM->getDataLayout());
1348 
1349  if (SrcM->getDataLayout() != DstM.getDataLayout()) {
1350  emitWarning("Linking two modules of different data layouts: '" +
1351  SrcM->getModuleIdentifier() + "' is '" +
1352  SrcM->getDataLayoutStr() + "' whereas '" +
1353  DstM.getModuleIdentifier() + "' is '" +
1354  DstM.getDataLayoutStr() + "'\n");
1355  }
1356 
1357  // Copy the target triple from the source to dest if the dest's is empty.
1358  if (DstM.getTargetTriple().empty() && !SrcM->getTargetTriple().empty())
1359  DstM.setTargetTriple(SrcM->getTargetTriple());
1360 
1361  Triple SrcTriple(SrcM->getTargetTriple()), DstTriple(DstM.getTargetTriple());
1362 
1363  if (!SrcM->getTargetTriple().empty()&&
1364  !SrcTriple.isCompatibleWith(DstTriple))
1365  emitWarning("Linking two modules of different target triples: " +
1366  SrcM->getModuleIdentifier() + "' is '" +
1367  SrcM->getTargetTriple() + "' whereas '" +
1368  DstM.getModuleIdentifier() + "' is '" + DstM.getTargetTriple() +
1369  "'\n");
1370 
1371  DstM.setTargetTriple(SrcTriple.merge(DstTriple));
1372 
1373  // Append the module inline asm string.
1374  if (!IsPerformingImport && !SrcM->getModuleInlineAsm().empty()) {
1375  std::string SrcModuleInlineAsm = adjustInlineAsm(SrcM->getModuleInlineAsm(),
1376  SrcTriple);
1377  if (DstM.getModuleInlineAsm().empty())
1378  DstM.setModuleInlineAsm(SrcModuleInlineAsm);
1379  else
1380  DstM.setModuleInlineAsm(DstM.getModuleInlineAsm() + "\n" +
1381  SrcModuleInlineAsm);
1382  }
1383 
1384  // Loop over all of the linked values to compute type mappings.
1385  computeTypeMapping();
1386 
1387  std::reverse(Worklist.begin(), Worklist.end());
1388  while (!Worklist.empty()) {
1389  GlobalValue *GV = Worklist.back();
1390  Worklist.pop_back();
1391 
1392  // Already mapped.
1393  if (ValueMap.find(GV) != ValueMap.end() ||
1394  AliasValueMap.find(GV) != AliasValueMap.end())
1395  continue;
1396 
1397  assert(!GV->isDeclaration());
1398  Mapper.mapValue(*GV);
1399  if (FoundError)
1400  return std::move(*FoundError);
1401  flushRAUWWorklist();
1402  }
1403 
1404  // Note that we are done linking global value bodies. This prevents
1405  // metadata linking from creating new references.
1406  DoneLinkingBodies = true;
1407  Mapper.addFlags(RF_NullMapMissingGlobalValues);
1408 
1409  // Remap all of the named MDNodes in Src into the DstM module. We do this
1410  // after linking GlobalValues so that MDNodes that reference GlobalValues
1411  // are properly remapped.
1412  linkNamedMDNodes();
1413 
1414  // Merge the module flags into the DstM module.
1415  return linkModuleFlagsMetadata();
1416 }
1417 
1419  : ETypes(E), IsPacked(P) {}
1420 
1422  : ETypes(ST->elements()), IsPacked(ST->isPacked()) {}
1423 
1425  return IsPacked == That.IsPacked && ETypes == That.ETypes;
1426 }
1427 
1429  return !this->operator==(That);
1430 }
1431 
1432 StructType *IRMover::StructTypeKeyInfo::getEmptyKey() {
1434 }
1435 
1436 StructType *IRMover::StructTypeKeyInfo::getTombstoneKey() {
1438 }
1439 
1440 unsigned IRMover::StructTypeKeyInfo::getHashValue(const KeyTy &Key) {
1441  return hash_combine(hash_combine_range(Key.ETypes.begin(), Key.ETypes.end()),
1442  Key.IsPacked);
1443 }
1444 
1445 unsigned IRMover::StructTypeKeyInfo::getHashValue(const StructType *ST) {
1446  return getHashValue(KeyTy(ST));
1447 }
1448 
1450  const StructType *RHS) {
1451  if (RHS == getEmptyKey() || RHS == getTombstoneKey())
1452  return false;
1453  return LHS == KeyTy(RHS);
1454 }
1455 
1457  const StructType *RHS) {
1458  if (RHS == getEmptyKey() || RHS == getTombstoneKey())
1459  return LHS == RHS;
1460  return KeyTy(LHS) == KeyTy(RHS);
1461 }
1462 
1464  assert(!Ty->isOpaque());
1465  NonOpaqueStructTypes.insert(Ty);
1466 }
1467 
1469  assert(!Ty->isOpaque());
1470  NonOpaqueStructTypes.insert(Ty);
1471  bool Removed = OpaqueStructTypes.erase(Ty);
1472  (void)Removed;
1473  assert(Removed);
1474 }
1475 
1477  assert(Ty->isOpaque());
1478  OpaqueStructTypes.insert(Ty);
1479 }
1480 
1481 StructType *
1483  bool IsPacked) {
1484  IRMover::StructTypeKeyInfo::KeyTy Key(ETypes, IsPacked);
1485  auto I = NonOpaqueStructTypes.find_as(Key);
1486  return I == NonOpaqueStructTypes.end() ? nullptr : *I;
1487 }
1488 
1490  if (Ty->isOpaque())
1491  return OpaqueStructTypes.count(Ty);
1492  auto I = NonOpaqueStructTypes.find(Ty);
1493  return I == NonOpaqueStructTypes.end() ? false : *I == Ty;
1494 }
1495 
1496 IRMover::IRMover(Module &M) : Composite(M) {
1497  TypeFinder StructTypes;
1498  StructTypes.run(M, /* OnlyNamed */ false);
1499  for (StructType *Ty : StructTypes) {
1500  if (Ty->isOpaque())
1501  IdentifiedStructTypes.addOpaque(Ty);
1502  else
1503  IdentifiedStructTypes.addNonOpaque(Ty);
1504  }
1505  // Self-map metadatas in the destination module. This is needed when
1506  // DebugTypeODRUniquing is enabled on the LLVMContext, since metadata in the
1507  // destination module may be reached from the source module.
1508  for (auto *MD : StructTypes.getVisitedMetadata()) {
1509  SharedMDs[MD].reset(const_cast<MDNode *>(MD));
1510  }
1511 }
1512 
1514  std::unique_ptr<Module> Src, ArrayRef<GlobalValue *> ValuesToLink,
1515  std::function<void(GlobalValue &, ValueAdder Add)> AddLazyFor,
1516  bool IsPerformingImport) {
1517  IRLinker TheIRLinker(Composite, SharedMDs, IdentifiedStructTypes,
1518  std::move(Src), ValuesToLink, std::move(AddLazyFor),
1519  IsPerformingImport);
1520  Error E = TheIRLinker.run();
1521  Composite.dropTriviallyDeadConstantArrays();
1522  return E;
1523 }
bool isDeclarationForLinker() const
Definition: GlobalValue.h:523
uint64_t CallInst * C
StringRef getSection() const
Get the custom section of this global if it has one.
Definition: GlobalObject.h:89
unsigned getAlignment() const
Definition: GlobalObject.h:58
reference emplace_back(ArgTypes &&... Args)
Definition: SmallVector.h:645
ThreadLocalMode getThreadLocalMode() const
Definition: GlobalValue.h:254
static MDTuple * get(LLVMContext &Context, ArrayRef< Metadata *> MDs)
Definition: Metadata.h:1132
bool hasLocalLinkage() const
Definition: GlobalValue.h:435
static Constant * getPointerBitCastOrAddrSpaceCast(Constant *C, Type *Ty)
Create a BitCast or AddrSpaceCast for a pointer type depending on the address space.
Definition: Constants.cpp:1611
Takes the max of the two values, which are required to be integers.
Definition: Module.h:145
MDNode * getOperand(unsigned i) const
Definition: Metadata.cpp:1080
const Constant * getInitializer() const
getInitializer - Return the initializer for this global variable.
This class represents lattice values for constants.
Definition: AllocatorList.h:23
size_type size() const
Determine the number of elements in the SetVector.
Definition: SetVector.h:77
KeyTy(ArrayRef< Type *> E, bool P)
Definition: IRMover.cpp:1418
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:65
iterator end()
Definition: Function.h:663
amdgpu Simplify well known AMD library false FunctionCallee Value const Twine & Name
LLVM_NODISCARD size_t rfind(char C, size_t From=npos) const
Search for the last character C in the string.
Definition: StringRef.h:345
Implements a dense probed hash-table based set.
Definition: DenseSet.h:249
Any global values not in value map are mapped to null instead of mapping to self. ...
Definition: ValueMapper.h:98
void addOperand(MDNode *M)
Definition: Metadata.cpp:1086
static PointerType * get(Type *ElementType, unsigned AddressSpace)
This constructs a pointer to an object of the specified type in a numbered address space...
Definition: Type.cpp:629
Externally visible function.
Definition: GlobalValue.h:48
LLVMContext & getContext() const
All values hold a context through their type.
Definition: Value.cpp:709
bool hasPrologueData() const
Check whether this function has prologue data.
Definition: Function.h:725
13: Structures
Definition: Type.h:72
Metadata node.
Definition: Metadata.h:863
F(f)
Context for (re-)mapping values (and metadata).
Definition: ValueMapper.h:141
const MDOperand & getOperand(unsigned I) const
Definition: Metadata.h:1068
unsigned getPointerAddressSpace() const
Get the address space of this pointer or pointer vector type.
Definition: DerivedTypes.h:534
void switchToNonOpaque(StructType *Ty)
Definition: IRMover.cpp:1468
bool isOpaque() const
Return true if this is a type with an identity that has no body specified yet.
Definition: DerivedTypes.h:300
bool hasExternalWeakLinkage() const
Definition: GlobalValue.h:436
Error takeError()
Take ownership of the stored error.
Definition: Error.h:552
15: Pointers
Definition: Type.h:74
void reserve(size_type N)
Definition: SmallVector.h:369
void setAlignment(unsigned Align)
Definition: Globals.cpp:115
void setOperand(unsigned I, MDNode *New)
Definition: Metadata.cpp:1088
12: Functions
Definition: Type.h:71
iterator end()
Get an iterator to the end of the SetVector.
Definition: SetVector.h:92
op_iterator op_end() const
Definition: Metadata.h:1062
Constant * getPrologueData() const
Get the prologue data associated with this function.
Definition: Function.cpp:1326
LLVMContext & getContext() const
Return the LLVMContext in which this type was uniqued.
Definition: Type.h:129
Adds a requirement that another module flag be present and have a specified value after linking is pe...
Definition: Module.h:129
Appends the two values, which are required to be metadata nodes.
Definition: Module.h:137
void copyMetadata(const GlobalObject *Src, unsigned Offset)
Copy metadata from Src, adjusting offsets by Offset.
Definition: Metadata.cpp:1450
A tuple of MDNodes.
Definition: Metadata.h:1325
bool hasPrefixData() const
Check whether this function has prefix data.
Definition: Function.h:716
DiagnosticSeverity
Defines the different supported severity of a diagnostic.
static ManagedStatic< DebugCounter > DC
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:80
ArrayRef< T > makeArrayRef(const T &OneElt)
Construct an ArrayRef from a single element.
Definition: ArrayRef.h:450
TypeID getTypeID() const
Return the type id for the type.
Definition: Type.h:137
void copyAttributesFrom(const GlobalValue *Src)
Definition: GlobalAlias.h:61
Class to represent struct types.
Definition: DerivedTypes.h:232
bool isConstant() const
If the value is a global constant, its value is immutable throughout the runtime execution of the pro...
This class consists of common code factored out of the SmallVector class to reduce code duplication b...
Definition: APFloat.h:41
unsigned getNumOperands() const
Definition: Metadata.cpp:1076
void setName(const Twine &Name)
Change the name of the value.
Definition: Value.cpp:285
Tagged union holding either a T or a Error.
Definition: CachePruning.h:22
Interface for custom diagnostic printing.
LLVM_NODISCARD StringRef substr(size_t Start, size_t N=npos) const
Return a reference to the substring from [Start, Start + N).
Definition: StringRef.h:578
uint64_t getNumElements() const
Definition: DerivedTypes.h:390
static StructType * get(LLVMContext &Context, ArrayRef< Type *> Elements, bool isPacked=false)
This static method is the primary way to create a literal StructType.
Definition: Type.cpp:341
Constant * getPrefixData() const
Get the prefix data associated with this function.
Definition: Function.cpp:1316
op_iterator op_begin() const
Definition: Metadata.h:1058
auto reverse(ContainerTy &&C, typename std::enable_if< has_rbegin< ContainerTy >::value >::type *=nullptr) -> decltype(make_range(C.rbegin(), C.rend()))
Definition: STLExtras.h:266
Key
PAL metadata keys.
llvm::Optional< Function * > remangleIntrinsicFunction(Function *F)
Definition: Function.cpp:1225
Class to represent function types.
Definition: DerivedTypes.h:102
Instruct the remapper to move distinct metadata instead of duplicating it when there are module-level...
Definition: ValueMapper.h:94
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:244
bool insert(const value_type &X)
Insert a new element into the SetVector.
Definition: SetVector.h:141
static bool isEqual(const Function &Caller, const Function &Callee)
Error move(std::unique_ptr< Module > Src, ArrayRef< GlobalValue *> ValuesToLink, std::function< void(GlobalValue &GV, ValueAdder Add)> AddLazyFor, bool IsPerformingImport)
Move in the provide values in ValuesToLink from Src.
Definition: IRMover.cpp:1513
ArchType getArch() const
getArch - Get the parsed architecture type of this triple.
Definition: Triple.h:294
#define T
Class to represent array types.
Definition: DerivedTypes.h:400
iterator find(const KeyT &Val)
Definition: ValueMap.h:161
iterator begin()
Get an iterator to the beginning of the SetVector.
Definition: SetVector.h:82
bool operator!=(const KeyTy &that) const
Definition: IRMover.cpp:1428
GlobalValue * getNamedValue(StringRef Name) const
Return the global value in the module with the specified name, of arbitrary type. ...
Definition: Module.cpp:113
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory)...
Definition: APInt.h:32
SmallString - A SmallString is just a SmallVector with methods and accessors that make it work better...
Definition: SmallString.h:25
bool hasPersonalityFn() const
Check whether this function has a personality function.
Definition: Function.h:707
LinkageTypes getLinkage() const
Definition: GlobalValue.h:450
void replaceAllUsesWith(Value *V)
Change all uses of this to point to a new Value.
Definition: Value.cpp:429
ValueT lookup(const KeyT &Val) const
lookup - Return the entry for the specified key, or a default constructed value if no such entry exis...
Definition: ValueMap.h:170
void setBody(ArrayRef< Type *> Elements, bool isPacked=false)
Specify a body for an opaque identified type.
Definition: Type.cpp:368
void takeName(Value *V)
Transfer the name from V to this value.
Definition: Value.cpp:291
Class to represent pointers.
Definition: DerivedTypes.h:498
Flag
These should be considered private to the implementation of the MCInstrDesc class.
Definition: MCInstrDesc.h:117
Constant * getAggregateElement(unsigned Elt) const
For aggregates (struct/array/vector) return the constant that corresponds to the specified element if...
Definition: Constants.cpp:344
bool hasAppendingLinkage() const
Definition: GlobalValue.h:432
StringRef getString() const
Definition: Metadata.cpp:463
static Constant * getBitCast(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:1782
ExternalWeak linkage description.
Definition: GlobalValue.h:57
static MDTuple * get(LLVMContext &Context, ArrayRef< Metadata *> MDs)
Definition: Metadata.h:1165
#define P(N)
This is a class that can be implemented by clients to materialize Values on demand.
Definition: ValueMapper.h:50
static Function * Create(FunctionType *Ty, LinkageTypes Linkage, unsigned AddrSpace, const Twine &N="", Module *M=nullptr)
Definition: Function.h:135
This is the base abstract class for diagnostic reporting in the backend.
void stealArgumentListFrom(Function &Src)
Steal arguments from another function.
Definition: Function.cpp:304
Emits an error if two values disagree, otherwise the resulting value is that of the operands...
Definition: Module.h:116
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
VisibilityTypes getVisibility() const
Definition: GlobalValue.h:232
bool hasName() const
Definition: Value.h:250
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:45
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
This is an important base class in LLVM.
Definition: Constant.h:41
unsigned getNumContainedTypes() const
Return the number of types in the derived type.
Definition: Type.h:338
This file contains the declarations for the subclasses of Constant, which represent the different fla...
std::pair< iterator, bool > insert(PtrType Ptr)
Inserts Ptr if and only if there is no element in the container equal to Ptr.
Definition: SmallPtrSet.h:370
bool isODRUniquingDebugTypes() const
Whether there is a string map for uniquing debug info identifiers across the context.
Optional< MDMapT > & getMDMap()
Definition: ValueMap.h:121
void splice(iterator where, iplist_impl &L2)
Definition: ilist.h:327
StringRef getName() const
Return the name for this struct type if it has an identity.
Definition: Type.cpp:499
static FunctionType * get(Type *Result, ArrayRef< Type *> Params, bool isVarArg)
This static method is the primary way of constructing a FunctionType.
Definition: Type.cpp:296
unsigned getAddressSpace() const
Return the address space of the Pointer type.
Definition: DerivedTypes.h:526
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
Error materialize()
Make sure this GlobalValue is fully read.
Definition: Globals.cpp:49
const Constant * stripPointerCasts() const
Definition: Constant.h:177
iterator erase(const_iterator CI)
Definition: SmallVector.h:438
size_t size() const
Definition: SmallVector.h:52
LLVM_NODISCARD char back() const
back - Get the last character in the string.
Definition: StringRef.h:141
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
Triple - Helper class for working with autoconf configuration names.
Definition: Triple.h:43
Base class for scope-like contexts.
static void getArrayElements(const Constant *C, SmallVectorImpl< Constant *> &Dest)
Definition: IRMover.cpp:790
iterator end()
Definition: ValueMap.h:141
14: Arrays
Definition: Type.h:73
A SetVector that performs no allocations if smaller than a certain size.
Definition: SetVector.h:297
static ErrorSuccess success()
Create a success value.
Definition: Error.h:326
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
void setSelectionKind(SelectionKind Val)
Definition: Comdat.h:45
16: SIMD &#39;packed&#39; format, or other vector type
Definition: Type.h:75
void dropTriviallyDeadConstantArrays()
Destroy ConstantArrays in LLVMContext if they are not used.
void run(const Module &M, bool onlyNamed)
Definition: TypeFinder.cpp:31
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:841
CHAIN = SC CHAIN, Imm128 - System call.
bool hasGlobalUnnamedAddr() const
Definition: GlobalValue.h:199
void print(DiagnosticPrinter &DP) const override
Print using the given DP a user-friendly message.
Definition: IRMover.cpp:349
bool operator==(const KeyTy &that) const
Definition: IRMover.cpp:1424
void setLinkage(LinkageTypes LT)
Definition: GlobalValue.h:444
Uses the specified value, regardless of the behavior or value of the other module.
Definition: Module.h:134
FunctionType * getFunctionType() const
Returns the FunctionType for me.
Definition: Function.h:163
bool isLiteral() const
Return true if this type is uniqued by structural equivalence, false if it is a struct definition...
Definition: DerivedTypes.h:296
static StringRef getTypeNamePrefix(StringRef Name)
Definition: IRMover.cpp:701
const Comdat * getComdat() const
Definition: Globals.cpp:170
hash_code hash_combine(const Ts &...args)
Combine values into a single hash_code.
Definition: Hashing.h:600
LinkDiagnosticInfo(DiagnosticSeverity Severity, const Twine &Msg)
Definition: IRMover.cpp:346
Emits a warning if two values disagree.
Definition: Module.h:120
hash_code hash_combine_range(InputIteratorT first, InputIteratorT last)
Compute a hash_code for a sequence of values.
Definition: Hashing.h:478
This is a class that can be implemented by clients to remap types when cloning constants and instruct...
Definition: ValueMapper.h:37
If this flag is set, the remapper ignores missing function-local entries (Argument, Instruction, BasicBlock) that are not in the value map.
Definition: ValueMapper.h:90
void setName(StringRef Name)
Change the name of this type to the specified name, or to a name with a suffix if there is a collisio...
Definition: Type.cpp:385
IRMover(Module &M)
Definition: IRMover.cpp:1496
void eraseFromParent()
This method unlinks &#39;this&#39; from the containing module and deletes it.
Definition: Globals.cpp:84
bool isPacked() const
Definition: DerivedTypes.h:292
bool isFunctionTy() const
True if this is an instance of FunctionType.
Definition: Type.h:214
static const size_t npos
Definition: StringRef.h:50
Appends the two values, which are required to be metadata nodes.
Definition: Module.h:142
LLVM_NODISCARD bool empty() const
Definition: SmallVector.h:55
StringRef getName() const
Return a constant reference to the value&#39;s name.
Definition: Value.cpp:214
void copyAttributesFrom(const GlobalVariable *Src)
copyAttributesFrom - copy all additional attributes (those not needed to create a GlobalVariable) fro...
Definition: Globals.cpp:385
#define I(x, y, z)
Definition: MD5.cpp:58
void setPrologueData(Constant *PrologueData)
Definition: Function.cpp:1331
static ArrayType * get(Type *ElementType, uint64_t NumElements)
This static method is the primary way to construct an ArrayType.
Definition: Type.cpp:580
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
Type * getValueType() const
Definition: GlobalValue.h:275
const BasicBlockListType & getBasicBlockList() const
Get the underlying elements of the Function...
Definition: Function.h:638
Rename collisions when linking (static functions).
Definition: GlobalValue.h:55
ValueT lookup(const_arg_type_t< KeyT > Val) const
lookup - Return the entry for the specified key, or a default constructed value if no such entry exis...
Definition: DenseMap.h:211
bool isDeclaration() const
Return true if the primary definition of this global value is outside of the current translation unit...
Definition: Globals.cpp:205
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
std::function< void(GlobalValue &)> ValueAdder
Definition: IRMover.h:64
A raw_ostream that writes to an std::string.
Definition: raw_ostream.h:482
StructType * findNonOpaque(ArrayRef< Type *> ETypes, bool IsPacked)
Definition: IRMover.cpp:1482
Module * getParent()
Get the module that this global value is contained inside of...
Definition: GlobalValue.h:565
LLVM Value Representation.
Definition: Value.h:72
Constant * getPersonalityFn() const
Get the personality function associated with this function.
Definition: Function.cpp:1306
static VectorType * get(Type *ElementType, unsigned NumElements)
This static method is the primary way to construct an VectorType.
Definition: Type.cpp:605
static StructType * create(LLVMContext &Context, StringRef Name)
This creates an identified struct.
Definition: Type.cpp:436
Lightweight error class with error context and mandatory checking.
Definition: Error.h:157
static std::string adjustInlineAsm(const std::string &InlineAsm, const Triple &Triple)
Return InlineAsm adjusted with target-specific directives if required.
Definition: IRMover.cpp:1329
static void forceRenaming(GlobalValue *GV, StringRef Name)
The LLVM SymbolTable class autorenames globals that conflict in the symbol table. ...
Definition: IRMover.cpp:541
Type * getElementType() const
Definition: DerivedTypes.h:391
print Print MemDeps of function
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
A single uniqued string.
Definition: Metadata.h:603
void setPersonalityFn(Constant *Fn)
Definition: Function.cpp:1311
unsigned getNumOperands() const
Return number of MDNode operands.
Definition: Metadata.h:1074
bool hasName() const
Return true if this is a named struct that has a non-empty name.
Definition: DerivedTypes.h:306
MDMapT & MD()
Definition: ValueMap.h:116
TypeFinder - Walk over a module, identifying all of the types that are used by the module...
Definition: TypeFinder.h:30
Root of the metadata hierarchy.
Definition: Metadata.h:57
Function Alias Analysis false
static IntegerType * getInt8Ty(LLVMContext &C)
Definition: Type.cpp:173
static GlobalAlias * create(Type *Ty, unsigned AddressSpace, LinkageTypes Linkage, const Twine &Name, Constant *Aliasee, Module *Parent)
If a parent module is specified, the alias is automatically inserted into the end of the specified mo...
Definition: Globals.cpp:422
PointerType * getType() const
Global values are always pointers.
Definition: GlobalValue.h:273
Type * getContainedType(unsigned i) const
This method is used to implement the type iterator (defined at the end of the file).
Definition: Type.h:332
std::error_code inconvertibleErrorCode()
The value returned by this function can be returned from convertToErrorCode for Error values where no...
Definition: Error.cpp:77
void setPrefixData(Constant *PrefixData)
Definition: Function.cpp:1321
void resize(size_type N)
Definition: SmallVector.h:344
const Constant * getAliasee() const
Definition: GlobalAlias.h:77