LLVM  9.0.0svn
IRMover.cpp
Go to the documentation of this file.
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  /// Replace all types in the source AttributeList with the
493  /// corresponding destination type.
494  AttributeList mapAttributeTypes(LLVMContext &C, AttributeList Attrs);
495 
496  /// Functions that take care of cloning a specific global value type
497  /// into the destination module.
498  GlobalVariable *copyGlobalVariableProto(const GlobalVariable *SGVar);
499  Function *copyFunctionProto(const Function *SF);
500  GlobalValue *copyGlobalAliasProto(const GlobalAlias *SGA);
501 
502  /// Perform "replace all uses with" operations. These work items need to be
503  /// performed as part of materialization, but we postpone them to happen after
504  /// materialization is done. The materializer called by ValueMapper is not
505  /// expected to delete constants, as ValueMapper is holding pointers to some
506  /// of them, but constant destruction may be indirectly triggered by RAUW.
507  /// Hence, the need to move this out of the materialization call chain.
508  void flushRAUWWorklist();
509 
510  /// When importing for ThinLTO, prevent importing of types listed on
511  /// the DICompileUnit that we don't need a copy of in the importing
512  /// module.
513  void prepareCompileUnitsForImport();
514  void linkNamedMDNodes();
515 
516 public:
517  IRLinker(Module &DstM, MDMapT &SharedMDs,
518  IRMover::IdentifiedStructTypeSet &Set, std::unique_ptr<Module> SrcM,
519  ArrayRef<GlobalValue *> ValuesToLink,
520  std::function<void(GlobalValue &, IRMover::ValueAdder)> AddLazyFor,
521  bool IsPerformingImport)
522  : DstM(DstM), SrcM(std::move(SrcM)), AddLazyFor(std::move(AddLazyFor)),
523  TypeMap(Set), GValMaterializer(*this), LValMaterializer(*this),
524  SharedMDs(SharedMDs), IsPerformingImport(IsPerformingImport),
525  Mapper(ValueMap, RF_MoveDistinctMDs | RF_IgnoreMissingLocals, &TypeMap,
526  &GValMaterializer),
527  AliasMCID(Mapper.registerAlternateMappingContext(AliasValueMap,
528  &LValMaterializer)) {
529  ValueMap.getMDMap() = std::move(SharedMDs);
530  for (GlobalValue *GV : ValuesToLink)
531  maybeAdd(GV);
532  if (IsPerformingImport)
533  prepareCompileUnitsForImport();
534  }
535  ~IRLinker() { SharedMDs = std::move(*ValueMap.getMDMap()); }
536 
537  Error run();
538  Value *materialize(Value *V, bool ForAlias);
539 };
540 }
541 
542 /// The LLVM SymbolTable class autorenames globals that conflict in the symbol
543 /// table. This is good for all clients except for us. Go through the trouble
544 /// to force this back.
546  // If the global doesn't force its name or if it already has the right name,
547  // there is nothing for us to do.
548  if (GV->hasLocalLinkage() || GV->getName() == Name)
549  return;
550 
551  Module *M = GV->getParent();
552 
553  // If there is a conflict, rename the conflict.
554  if (GlobalValue *ConflictGV = M->getNamedValue(Name)) {
555  GV->takeName(ConflictGV);
556  ConflictGV->setName(Name); // This will cause ConflictGV to get renamed
557  assert(ConflictGV->getName() != Name && "forceRenaming didn't work");
558  } else {
559  GV->setName(Name); // Force the name back
560  }
561 }
562 
563 Value *GlobalValueMaterializer::materialize(Value *SGV) {
564  return TheIRLinker.materialize(SGV, false);
565 }
566 
567 Value *LocalValueMaterializer::materialize(Value *SGV) {
568  return TheIRLinker.materialize(SGV, true);
569 }
570 
571 Value *IRLinker::materialize(Value *V, bool ForAlias) {
572  auto *SGV = dyn_cast<GlobalValue>(V);
573  if (!SGV)
574  return nullptr;
575 
576  Expected<Constant *> NewProto = linkGlobalValueProto(SGV, ForAlias);
577  if (!NewProto) {
578  setError(NewProto.takeError());
579  return nullptr;
580  }
581  if (!*NewProto)
582  return nullptr;
583 
584  GlobalValue *New = dyn_cast<GlobalValue>(*NewProto);
585  if (!New)
586  return *NewProto;
587 
588  // If we already created the body, just return.
589  if (auto *F = dyn_cast<Function>(New)) {
590  if (!F->isDeclaration())
591  return New;
592  } else if (auto *V = dyn_cast<GlobalVariable>(New)) {
593  if (V->hasInitializer() || V->hasAppendingLinkage())
594  return New;
595  } else {
596  auto *A = cast<GlobalAlias>(New);
597  if (A->getAliasee())
598  return New;
599  }
600 
601  // When linking a global for an alias, it will always be linked. However we
602  // need to check if it was not already scheduled to satisfy a reference from a
603  // regular global value initializer. We know if it has been schedule if the
604  // "New" GlobalValue that is mapped here for the alias is the same as the one
605  // already mapped. If there is an entry in the ValueMap but the value is
606  // different, it means that the value already had a definition in the
607  // destination module (linkonce for instance), but we need a new definition
608  // for the alias ("New" will be different.
609  if (ForAlias && ValueMap.lookup(SGV) == New)
610  return New;
611 
612  if (ForAlias || shouldLink(New, *SGV))
613  setError(linkGlobalValueBody(*New, *SGV));
614 
615  return New;
616 }
617 
618 /// Loop through the global variables in the src module and merge them into the
619 /// dest module.
620 GlobalVariable *IRLinker::copyGlobalVariableProto(const GlobalVariable *SGVar) {
621  // No linking to be performed or linking from the source: simply create an
622  // identical version of the symbol over in the dest module... the
623  // initializer will be filled in later by LinkGlobalInits.
624  GlobalVariable *NewDGV =
625  new GlobalVariable(DstM, TypeMap.get(SGVar->getValueType()),
627  /*init*/ nullptr, SGVar->getName(),
628  /*insertbefore*/ nullptr, SGVar->getThreadLocalMode(),
629  SGVar->getType()->getAddressSpace());
630  NewDGV->setAlignment(SGVar->getAlignment());
631  NewDGV->copyAttributesFrom(SGVar);
632  return NewDGV;
633 }
634 
635 AttributeList IRLinker::mapAttributeTypes(LLVMContext &C, AttributeList Attrs) {
636  for (unsigned i = 0; i < Attrs.getNumAttrSets(); ++i) {
637  if (Attrs.hasAttribute(i, Attribute::ByVal)) {
638  Type *Ty = Attrs.getAttribute(i, Attribute::ByVal).getValueAsType();
639  if (!Ty)
640  continue;
641 
642  Attrs = Attrs.removeAttribute(C, i, Attribute::ByVal);
643  Attrs = Attrs.addAttribute(
644  C, i, Attribute::getWithByValType(C, TypeMap.get(Ty)));
645  }
646  }
647  return Attrs;
648 }
649 
650 /// Link the function in the source module into the destination module if
651 /// needed, setting up mapping information.
652 Function *IRLinker::copyFunctionProto(const Function *SF) {
653  // If there is no linkage to be performed or we are linking from the source,
654  // bring SF over.
655  auto *F =
656  Function::Create(TypeMap.get(SF->getFunctionType()),
657  GlobalValue::ExternalLinkage, SF->getName(), &DstM);
658  F->copyAttributesFrom(SF);
659  F->setAttributes(mapAttributeTypes(F->getContext(), F->getAttributes()));
660  return F;
661 }
662 
663 /// Set up prototypes for any aliases that come over from the source module.
664 GlobalValue *IRLinker::copyGlobalAliasProto(const GlobalAlias *SGA) {
665  // If there is no linkage to be performed or we're linking from the source,
666  // bring over SGA.
667  auto *Ty = TypeMap.get(SGA->getValueType());
668  auto *GA =
670  GlobalValue::ExternalLinkage, SGA->getName(), &DstM);
671  GA->copyAttributesFrom(SGA);
672  return GA;
673 }
674 
675 GlobalValue *IRLinker::copyGlobalValueProto(const GlobalValue *SGV,
676  bool ForDefinition) {
677  GlobalValue *NewGV;
678  if (auto *SGVar = dyn_cast<GlobalVariable>(SGV)) {
679  NewGV = copyGlobalVariableProto(SGVar);
680  } else if (auto *SF = dyn_cast<Function>(SGV)) {
681  NewGV = copyFunctionProto(SF);
682  } else {
683  if (ForDefinition)
684  NewGV = copyGlobalAliasProto(cast<GlobalAlias>(SGV));
685  else if (SGV->getValueType()->isFunctionTy())
686  NewGV =
687  Function::Create(cast<FunctionType>(TypeMap.get(SGV->getValueType())),
688  GlobalValue::ExternalLinkage, SGV->getName(), &DstM);
689  else
690  NewGV = new GlobalVariable(
691  DstM, TypeMap.get(SGV->getValueType()),
692  /*isConstant*/ false, GlobalValue::ExternalLinkage,
693  /*init*/ nullptr, SGV->getName(),
694  /*insertbefore*/ nullptr, SGV->getThreadLocalMode(),
695  SGV->getType()->getAddressSpace());
696  }
697 
698  if (ForDefinition)
699  NewGV->setLinkage(SGV->getLinkage());
700  else if (SGV->hasExternalWeakLinkage())
702 
703  if (auto *NewGO = dyn_cast<GlobalObject>(NewGV)) {
704  // Metadata for global variables and function declarations is copied eagerly.
705  if (isa<GlobalVariable>(SGV) || SGV->isDeclaration())
706  NewGO->copyMetadata(cast<GlobalObject>(SGV), 0);
707  }
708 
709  // Remove these copied constants in case this stays a declaration, since
710  // they point to the source module. If the def is linked the values will
711  // be mapped in during linkFunctionBody.
712  if (auto *NewF = dyn_cast<Function>(NewGV)) {
713  NewF->setPersonalityFn(nullptr);
714  NewF->setPrefixData(nullptr);
715  NewF->setPrologueData(nullptr);
716  }
717 
718  return NewGV;
719 }
720 
722  size_t DotPos = Name.rfind('.');
723  return (DotPos == 0 || DotPos == StringRef::npos || Name.back() == '.' ||
724  !isdigit(static_cast<unsigned char>(Name[DotPos + 1])))
725  ? Name
726  : Name.substr(0, DotPos);
727 }
728 
729 /// Loop over all of the linked values to compute type mappings. For example,
730 /// if we link "extern Foo *x" and "Foo *x = NULL", then we have two struct
731 /// types 'Foo' but one got renamed when the module was loaded into the same
732 /// LLVMContext.
733 void IRLinker::computeTypeMapping() {
734  for (GlobalValue &SGV : SrcM->globals()) {
735  GlobalValue *DGV = getLinkedToGlobal(&SGV);
736  if (!DGV)
737  continue;
738 
739  if (!DGV->hasAppendingLinkage() || !SGV.hasAppendingLinkage()) {
740  TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
741  continue;
742  }
743 
744  // Unify the element type of appending arrays.
745  ArrayType *DAT = cast<ArrayType>(DGV->getValueType());
746  ArrayType *SAT = cast<ArrayType>(SGV.getValueType());
747  TypeMap.addTypeMapping(DAT->getElementType(), SAT->getElementType());
748  }
749 
750  for (GlobalValue &SGV : *SrcM)
751  if (GlobalValue *DGV = getLinkedToGlobal(&SGV))
752  TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
753 
754  for (GlobalValue &SGV : SrcM->aliases())
755  if (GlobalValue *DGV = getLinkedToGlobal(&SGV))
756  TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
757 
758  // Incorporate types by name, scanning all the types in the source module.
759  // At this point, the destination module may have a type "%foo = { i32 }" for
760  // example. When the source module got loaded into the same LLVMContext, if
761  // it had the same type, it would have been renamed to "%foo.42 = { i32 }".
762  std::vector<StructType *> Types = SrcM->getIdentifiedStructTypes();
763  for (StructType *ST : Types) {
764  if (!ST->hasName())
765  continue;
766 
767  if (TypeMap.DstStructTypesSet.hasType(ST)) {
768  // This is actually a type from the destination module.
769  // getIdentifiedStructTypes() can have found it by walking debug info
770  // metadata nodes, some of which get linked by name when ODR Type Uniquing
771  // is enabled on the Context, from the source to the destination module.
772  continue;
773  }
774 
775  auto STTypePrefix = getTypeNamePrefix(ST->getName());
776  if (STTypePrefix.size()== ST->getName().size())
777  continue;
778 
779  // Check to see if the destination module has a struct with the prefix name.
780  StructType *DST = DstM.getTypeByName(STTypePrefix);
781  if (!DST)
782  continue;
783 
784  // Don't use it if this actually came from the source module. They're in
785  // the same LLVMContext after all. Also don't use it unless the type is
786  // actually used in the destination module. This can happen in situations
787  // like this:
788  //
789  // Module A Module B
790  // -------- --------
791  // %Z = type { %A } %B = type { %C.1 }
792  // %A = type { %B.1, [7 x i8] } %C.1 = type { i8* }
793  // %B.1 = type { %C } %A.2 = type { %B.3, [5 x i8] }
794  // %C = type { i8* } %B.3 = type { %C.1 }
795  //
796  // When we link Module B with Module A, the '%B' in Module B is
797  // used. However, that would then use '%C.1'. But when we process '%C.1',
798  // we prefer to take the '%C' version. So we are then left with both
799  // '%C.1' and '%C' being used for the same types. This leads to some
800  // variables using one type and some using the other.
801  if (TypeMap.DstStructTypesSet.hasType(DST))
802  TypeMap.addTypeMapping(DST, ST);
803  }
804 
805  // Now that we have discovered all of the type equivalences, get a body for
806  // any 'opaque' types in the dest module that are now resolved.
807  TypeMap.linkDefinedTypeBodies();
808 }
809 
810 static void getArrayElements(const Constant *C,
812  unsigned NumElements = cast<ArrayType>(C->getType())->getNumElements();
813 
814  for (unsigned i = 0; i != NumElements; ++i)
815  Dest.push_back(C->getAggregateElement(i));
816 }
817 
818 /// If there were any appending global variables, link them together now.
820 IRLinker::linkAppendingVarProto(GlobalVariable *DstGV,
821  const GlobalVariable *SrcGV) {
822  Type *EltTy = cast<ArrayType>(TypeMap.get(SrcGV->getValueType()))
823  ->getElementType();
824 
825  // FIXME: This upgrade is done during linking to support the C API. Once the
826  // old form is deprecated, we should move this upgrade to
827  // llvm::UpgradeGlobalVariable() and simplify the logic here and in
828  // Mapper::mapAppendingVariable() in ValueMapper.cpp.
829  StringRef Name = SrcGV->getName();
830  bool IsNewStructor = false;
831  bool IsOldStructor = false;
832  if (Name == "llvm.global_ctors" || Name == "llvm.global_dtors") {
833  if (cast<StructType>(EltTy)->getNumElements() == 3)
834  IsNewStructor = true;
835  else
836  IsOldStructor = true;
837  }
838 
839  PointerType *VoidPtrTy = Type::getInt8Ty(SrcGV->getContext())->getPointerTo();
840  if (IsOldStructor) {
841  auto &ST = *cast<StructType>(EltTy);
842  Type *Tys[3] = {ST.getElementType(0), ST.getElementType(1), VoidPtrTy};
843  EltTy = StructType::get(SrcGV->getContext(), Tys, false);
844  }
845 
846  uint64_t DstNumElements = 0;
847  if (DstGV) {
848  ArrayType *DstTy = cast<ArrayType>(DstGV->getValueType());
849  DstNumElements = DstTy->getNumElements();
850 
851  if (!SrcGV->hasAppendingLinkage() || !DstGV->hasAppendingLinkage())
852  return stringErr(
853  "Linking globals named '" + SrcGV->getName() +
854  "': can only link appending global with another appending "
855  "global!");
856 
857  // Check to see that they two arrays agree on type.
858  if (EltTy != DstTy->getElementType())
859  return stringErr("Appending variables with different element types!");
860  if (DstGV->isConstant() != SrcGV->isConstant())
861  return stringErr("Appending variables linked with different const'ness!");
862 
863  if (DstGV->getAlignment() != SrcGV->getAlignment())
864  return stringErr(
865  "Appending variables with different alignment need to be linked!");
866 
867  if (DstGV->getVisibility() != SrcGV->getVisibility())
868  return stringErr(
869  "Appending variables with different visibility need to be linked!");
870 
871  if (DstGV->hasGlobalUnnamedAddr() != SrcGV->hasGlobalUnnamedAddr())
872  return stringErr(
873  "Appending variables with different unnamed_addr need to be linked!");
874 
875  if (DstGV->getSection() != SrcGV->getSection())
876  return stringErr(
877  "Appending variables with different section name need to be linked!");
878  }
879 
880  SmallVector<Constant *, 16> SrcElements;
881  getArrayElements(SrcGV->getInitializer(), SrcElements);
882 
883  if (IsNewStructor) {
884  auto It = remove_if(SrcElements, [this](Constant *E) {
885  auto *Key =
887  if (!Key)
888  return false;
889  GlobalValue *DGV = getLinkedToGlobal(Key);
890  return !shouldLink(DGV, *Key);
891  });
892  SrcElements.erase(It, SrcElements.end());
893  }
894  uint64_t NewSize = DstNumElements + SrcElements.size();
895  ArrayType *NewType = ArrayType::get(EltTy, NewSize);
896 
897  // Create the new global variable.
898  GlobalVariable *NG = new GlobalVariable(
899  DstM, NewType, SrcGV->isConstant(), SrcGV->getLinkage(),
900  /*init*/ nullptr, /*name*/ "", DstGV, SrcGV->getThreadLocalMode(),
901  SrcGV->getType()->getAddressSpace());
902 
903  NG->copyAttributesFrom(SrcGV);
904  forceRenaming(NG, SrcGV->getName());
905 
906  Constant *Ret = ConstantExpr::getBitCast(NG, TypeMap.get(SrcGV->getType()));
907 
908  Mapper.scheduleMapAppendingVariable(*NG,
909  DstGV ? DstGV->getInitializer() : nullptr,
910  IsOldStructor, SrcElements);
911 
912  // Replace any uses of the two global variables with uses of the new
913  // global.
914  if (DstGV) {
915  RAUWWorklist.push_back(
916  std::make_pair(DstGV, ConstantExpr::getBitCast(NG, DstGV->getType())));
917  }
918 
919  return Ret;
920 }
921 
922 bool IRLinker::shouldLink(GlobalValue *DGV, GlobalValue &SGV) {
923  if (ValuesToLink.count(&SGV) || SGV.hasLocalLinkage())
924  return true;
925 
926  if (DGV && !DGV->isDeclarationForLinker())
927  return false;
928 
929  if (SGV.isDeclaration() || DoneLinkingBodies)
930  return false;
931 
932  // Callback to the client to give a chance to lazily add the Global to the
933  // list of value to link.
934  bool LazilyAdded = false;
935  AddLazyFor(SGV, [this, &LazilyAdded](GlobalValue &GV) {
936  maybeAdd(&GV);
937  LazilyAdded = true;
938  });
939  return LazilyAdded;
940 }
941 
942 Expected<Constant *> IRLinker::linkGlobalValueProto(GlobalValue *SGV,
943  bool ForAlias) {
944  GlobalValue *DGV = getLinkedToGlobal(SGV);
945 
946  bool ShouldLink = shouldLink(DGV, *SGV);
947 
948  // just missing from map
949  if (ShouldLink) {
950  auto I = ValueMap.find(SGV);
951  if (I != ValueMap.end())
952  return cast<Constant>(I->second);
953 
954  I = AliasValueMap.find(SGV);
955  if (I != AliasValueMap.end())
956  return cast<Constant>(I->second);
957  }
958 
959  if (!ShouldLink && ForAlias)
960  DGV = nullptr;
961 
962  // Handle the ultra special appending linkage case first.
963  assert(!DGV || SGV->hasAppendingLinkage() == DGV->hasAppendingLinkage());
964  if (SGV->hasAppendingLinkage())
965  return linkAppendingVarProto(cast_or_null<GlobalVariable>(DGV),
966  cast<GlobalVariable>(SGV));
967 
968  GlobalValue *NewGV;
969  if (DGV && !ShouldLink) {
970  NewGV = DGV;
971  } else {
972  // If we are done linking global value bodies (i.e. we are performing
973  // metadata linking), don't link in the global value due to this
974  // reference, simply map it to null.
975  if (DoneLinkingBodies)
976  return nullptr;
977 
978  NewGV = copyGlobalValueProto(SGV, ShouldLink || ForAlias);
979  if (ShouldLink || !ForAlias)
980  forceRenaming(NewGV, SGV->getName());
981  }
982 
983  // Overloaded intrinsics have overloaded types names as part of their
984  // names. If we renamed overloaded types we should rename the intrinsic
985  // as well.
986  if (Function *F = dyn_cast<Function>(NewGV))
987  if (auto Remangled = Intrinsic::remangleIntrinsicFunction(F))
988  NewGV = Remangled.getValue();
989 
990  if (ShouldLink || ForAlias) {
991  if (const Comdat *SC = SGV->getComdat()) {
992  if (auto *GO = dyn_cast<GlobalObject>(NewGV)) {
993  Comdat *DC = DstM.getOrInsertComdat(SC->getName());
994  DC->setSelectionKind(SC->getSelectionKind());
995  GO->setComdat(DC);
996  }
997  }
998  }
999 
1000  if (!ShouldLink && ForAlias)
1002 
1003  Constant *C = NewGV;
1004  // Only create a bitcast if necessary. In particular, with
1005  // DebugTypeODRUniquing we may reach metadata in the destination module
1006  // containing a GV from the source module, in which case SGV will be
1007  // the same as DGV and NewGV, and TypeMap.get() will assert since it
1008  // assumes it is being invoked on a type in the source module.
1009  if (DGV && NewGV != SGV) {
1011  NewGV, TypeMap.get(SGV->getType()));
1012  }
1013 
1014  if (DGV && NewGV != DGV) {
1015  // Schedule "replace all uses with" to happen after materializing is
1016  // done. It is not safe to do it now, since ValueMapper may be holding
1017  // pointers to constants that will get deleted if RAUW runs.
1018  RAUWWorklist.push_back(std::make_pair(
1019  DGV,
1021  }
1022 
1023  return C;
1024 }
1025 
1026 /// Update the initializers in the Dest module now that all globals that may be
1027 /// referenced are in Dest.
1028 void IRLinker::linkGlobalVariable(GlobalVariable &Dst, GlobalVariable &Src) {
1029  // Figure out what the initializer looks like in the dest module.
1030  Mapper.scheduleMapGlobalInitializer(Dst, *Src.getInitializer());
1031 }
1032 
1033 /// Copy the source function over into the dest function and fix up references
1034 /// to values. At this point we know that Dest is an external function, and
1035 /// that Src is not.
1036 Error IRLinker::linkFunctionBody(Function &Dst, Function &Src) {
1037  assert(Dst.isDeclaration() && !Src.isDeclaration());
1038 
1039  // Materialize if needed.
1040  if (Error Err = Src.materialize())
1041  return Err;
1042 
1043  // Link in the operands without remapping.
1044  if (Src.hasPrefixData())
1045  Dst.setPrefixData(Src.getPrefixData());
1046  if (Src.hasPrologueData())
1047  Dst.setPrologueData(Src.getPrologueData());
1048  if (Src.hasPersonalityFn())
1050 
1051  // Copy over the metadata attachments without remapping.
1052  Dst.copyMetadata(&Src, 0);
1053 
1054  // Steal arguments and splice the body of Src into Dst.
1055  Dst.stealArgumentListFrom(Src);
1056  Dst.getBasicBlockList().splice(Dst.end(), Src.getBasicBlockList());
1057 
1058  // Everything has been moved over. Remap it.
1059  Mapper.scheduleRemapFunction(Dst);
1060  return Error::success();
1061 }
1062 
1063 void IRLinker::linkAliasBody(GlobalAlias &Dst, GlobalAlias &Src) {
1064  Mapper.scheduleMapGlobalAliasee(Dst, *Src.getAliasee(), AliasMCID);
1065 }
1066 
1067 Error IRLinker::linkGlobalValueBody(GlobalValue &Dst, GlobalValue &Src) {
1068  if (auto *F = dyn_cast<Function>(&Src))
1069  return linkFunctionBody(cast<Function>(Dst), *F);
1070  if (auto *GVar = dyn_cast<GlobalVariable>(&Src)) {
1071  linkGlobalVariable(cast<GlobalVariable>(Dst), *GVar);
1072  return Error::success();
1073  }
1074  linkAliasBody(cast<GlobalAlias>(Dst), cast<GlobalAlias>(Src));
1075  return Error::success();
1076 }
1077 
1078 void IRLinker::flushRAUWWorklist() {
1079  for (const auto Elem : RAUWWorklist) {
1080  GlobalValue *Old;
1081  Value *New;
1082  std::tie(Old, New) = Elem;
1083 
1084  Old->replaceAllUsesWith(New);
1085  Old->eraseFromParent();
1086  }
1087  RAUWWorklist.clear();
1088 }
1089 
1090 void IRLinker::prepareCompileUnitsForImport() {
1091  NamedMDNode *SrcCompileUnits = SrcM->getNamedMetadata("llvm.dbg.cu");
1092  if (!SrcCompileUnits)
1093  return;
1094  // When importing for ThinLTO, prevent importing of types listed on
1095  // the DICompileUnit that we don't need a copy of in the importing
1096  // module. They will be emitted by the originating module.
1097  for (unsigned I = 0, E = SrcCompileUnits->getNumOperands(); I != E; ++I) {
1098  auto *CU = cast<DICompileUnit>(SrcCompileUnits->getOperand(I));
1099  assert(CU && "Expected valid compile unit");
1100  // Enums, macros, and retained types don't need to be listed on the
1101  // imported DICompileUnit. This means they will only be imported
1102  // if reached from the mapped IR. Do this by setting their value map
1103  // entries to nullptr, which will automatically prevent their importing
1104  // when reached from the DICompileUnit during metadata mapping.
1105  ValueMap.MD()[CU->getRawEnumTypes()].reset(nullptr);
1106  ValueMap.MD()[CU->getRawMacros()].reset(nullptr);
1107  ValueMap.MD()[CU->getRawRetainedTypes()].reset(nullptr);
1108  // The original definition (or at least its debug info - if the variable is
1109  // internalized an optimized away) will remain in the source module, so
1110  // there's no need to import them.
1111  // If LLVM ever does more advanced optimizations on global variables
1112  // (removing/localizing write operations, for instance) that can track
1113  // through debug info, this decision may need to be revisited - but do so
1114  // with care when it comes to debug info size. Emitting small CUs containing
1115  // only a few imported entities into every destination module may be very
1116  // size inefficient.
1117  ValueMap.MD()[CU->getRawGlobalVariables()].reset(nullptr);
1118 
1119  // Imported entities only need to be mapped in if they have local
1120  // scope, as those might correspond to an imported entity inside a
1121  // function being imported (any locally scoped imported entities that
1122  // don't end up referenced by an imported function will not be emitted
1123  // into the object). Imported entities not in a local scope
1124  // (e.g. on the namespace) only need to be emitted by the originating
1125  // module. Create a list of the locally scoped imported entities, and
1126  // replace the source CUs imported entity list with the new list, so
1127  // only those are mapped in.
1128  // FIXME: Locally-scoped imported entities could be moved to the
1129  // functions they are local to instead of listing them on the CU, and
1130  // we would naturally only link in those needed by function importing.
1131  SmallVector<TrackingMDNodeRef, 4> AllImportedModules;
1132  bool ReplaceImportedEntities = false;
1133  for (auto *IE : CU->getImportedEntities()) {
1134  DIScope *Scope = IE->getScope();
1135  assert(Scope && "Invalid Scope encoding!");
1136  if (isa<DILocalScope>(Scope))
1137  AllImportedModules.emplace_back(IE);
1138  else
1139  ReplaceImportedEntities = true;
1140  }
1141  if (ReplaceImportedEntities) {
1142  if (!AllImportedModules.empty())
1143  CU->replaceImportedEntities(MDTuple::get(
1144  CU->getContext(),
1145  SmallVector<Metadata *, 16>(AllImportedModules.begin(),
1146  AllImportedModules.end())));
1147  else
1148  // If there were no local scope imported entities, we can map
1149  // the whole list to nullptr.
1150  ValueMap.MD()[CU->getRawImportedEntities()].reset(nullptr);
1151  }
1152  }
1153 }
1154 
1155 /// Insert all of the named MDNodes in Src into the Dest module.
1156 void IRLinker::linkNamedMDNodes() {
1157  const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
1158  for (const NamedMDNode &NMD : SrcM->named_metadata()) {
1159  // Don't link module flags here. Do them separately.
1160  if (&NMD == SrcModFlags)
1161  continue;
1162  NamedMDNode *DestNMD = DstM.getOrInsertNamedMetadata(NMD.getName());
1163  // Add Src elements into Dest node.
1164  for (const MDNode *Op : NMD.operands())
1165  DestNMD->addOperand(Mapper.mapMDNode(*Op));
1166  }
1167 }
1168 
1169 /// Merge the linker flags in Src into the Dest module.
1170 Error IRLinker::linkModuleFlagsMetadata() {
1171  // If the source module has no module flags, we are done.
1172  const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
1173  if (!SrcModFlags)
1174  return Error::success();
1175 
1176  // If the destination module doesn't have module flags yet, then just copy
1177  // over the source module's flags.
1178  NamedMDNode *DstModFlags = DstM.getOrInsertModuleFlagsMetadata();
1179  if (DstModFlags->getNumOperands() == 0) {
1180  for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I)
1181  DstModFlags->addOperand(SrcModFlags->getOperand(I));
1182 
1183  return Error::success();
1184  }
1185 
1186  // First build a map of the existing module flags and requirements.
1188  SmallSetVector<MDNode *, 16> Requirements;
1189  for (unsigned I = 0, E = DstModFlags->getNumOperands(); I != E; ++I) {
1190  MDNode *Op = DstModFlags->getOperand(I);
1191  ConstantInt *Behavior = mdconst::extract<ConstantInt>(Op->getOperand(0));
1192  MDString *ID = cast<MDString>(Op->getOperand(1));
1193 
1194  if (Behavior->getZExtValue() == Module::Require) {
1195  Requirements.insert(cast<MDNode>(Op->getOperand(2)));
1196  } else {
1197  Flags[ID] = std::make_pair(Op, I);
1198  }
1199  }
1200 
1201  // Merge in the flags from the source module, and also collect its set of
1202  // requirements.
1203  for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I) {
1204  MDNode *SrcOp = SrcModFlags->getOperand(I);
1205  ConstantInt *SrcBehavior =
1206  mdconst::extract<ConstantInt>(SrcOp->getOperand(0));
1207  MDString *ID = cast<MDString>(SrcOp->getOperand(1));
1208  MDNode *DstOp;
1209  unsigned DstIndex;
1210  std::tie(DstOp, DstIndex) = Flags.lookup(ID);
1211  unsigned SrcBehaviorValue = SrcBehavior->getZExtValue();
1212 
1213  // If this is a requirement, add it and continue.
1214  if (SrcBehaviorValue == Module::Require) {
1215  // If the destination module does not already have this requirement, add
1216  // it.
1217  if (Requirements.insert(cast<MDNode>(SrcOp->getOperand(2)))) {
1218  DstModFlags->addOperand(SrcOp);
1219  }
1220  continue;
1221  }
1222 
1223  // If there is no existing flag with this ID, just add it.
1224  if (!DstOp) {
1225  Flags[ID] = std::make_pair(SrcOp, DstModFlags->getNumOperands());
1226  DstModFlags->addOperand(SrcOp);
1227  continue;
1228  }
1229 
1230  // Otherwise, perform a merge.
1231  ConstantInt *DstBehavior =
1232  mdconst::extract<ConstantInt>(DstOp->getOperand(0));
1233  unsigned DstBehaviorValue = DstBehavior->getZExtValue();
1234 
1235  auto overrideDstValue = [&]() {
1236  DstModFlags->setOperand(DstIndex, SrcOp);
1237  Flags[ID].first = SrcOp;
1238  };
1239 
1240  // If either flag has override behavior, handle it first.
1241  if (DstBehaviorValue == Module::Override) {
1242  // Diagnose inconsistent flags which both have override behavior.
1243  if (SrcBehaviorValue == Module::Override &&
1244  SrcOp->getOperand(2) != DstOp->getOperand(2))
1245  return stringErr("linking module flags '" + ID->getString() +
1246  "': IDs have conflicting override values in '" +
1247  SrcM->getModuleIdentifier() + "' and '" +
1248  DstM.getModuleIdentifier() + "'");
1249  continue;
1250  } else if (SrcBehaviorValue == Module::Override) {
1251  // Update the destination flag to that of the source.
1252  overrideDstValue();
1253  continue;
1254  }
1255 
1256  // Diagnose inconsistent merge behavior types.
1257  if (SrcBehaviorValue != DstBehaviorValue)
1258  return stringErr("linking module flags '" + ID->getString() +
1259  "': IDs have conflicting behaviors in '" +
1260  SrcM->getModuleIdentifier() + "' and '" +
1261  DstM.getModuleIdentifier() + "'");
1262 
1263  auto replaceDstValue = [&](MDNode *New) {
1264  Metadata *FlagOps[] = {DstOp->getOperand(0), ID, New};
1265  MDNode *Flag = MDNode::get(DstM.getContext(), FlagOps);
1266  DstModFlags->setOperand(DstIndex, Flag);
1267  Flags[ID].first = Flag;
1268  };
1269 
1270  // Perform the merge for standard behavior types.
1271  switch (SrcBehaviorValue) {
1272  case Module::Require:
1273  case Module::Override:
1274  llvm_unreachable("not possible");
1275  case Module::Error: {
1276  // Emit an error if the values differ.
1277  if (SrcOp->getOperand(2) != DstOp->getOperand(2))
1278  return stringErr("linking module flags '" + ID->getString() +
1279  "': IDs have conflicting values in '" +
1280  SrcM->getModuleIdentifier() + "' and '" +
1281  DstM.getModuleIdentifier() + "'");
1282  continue;
1283  }
1284  case Module::Warning: {
1285  // Emit a warning if the values differ.
1286  if (SrcOp->getOperand(2) != DstOp->getOperand(2)) {
1287  std::string str;
1288  raw_string_ostream(str)
1289  << "linking module flags '" << ID->getString()
1290  << "': IDs have conflicting values ('" << *SrcOp->getOperand(2)
1291  << "' from " << SrcM->getModuleIdentifier() << " with '"
1292  << *DstOp->getOperand(2) << "' from " << DstM.getModuleIdentifier()
1293  << ')';
1294  emitWarning(str);
1295  }
1296  continue;
1297  }
1298  case Module::Max: {
1299  ConstantInt *DstValue =
1300  mdconst::extract<ConstantInt>(DstOp->getOperand(2));
1301  ConstantInt *SrcValue =
1302  mdconst::extract<ConstantInt>(SrcOp->getOperand(2));
1303  if (SrcValue->getZExtValue() > DstValue->getZExtValue())
1304  overrideDstValue();
1305  break;
1306  }
1307  case Module::Append: {
1308  MDNode *DstValue = cast<MDNode>(DstOp->getOperand(2));
1309  MDNode *SrcValue = cast<MDNode>(SrcOp->getOperand(2));
1311  MDs.reserve(DstValue->getNumOperands() + SrcValue->getNumOperands());
1312  MDs.append(DstValue->op_begin(), DstValue->op_end());
1313  MDs.append(SrcValue->op_begin(), SrcValue->op_end());
1314 
1315  replaceDstValue(MDNode::get(DstM.getContext(), MDs));
1316  break;
1317  }
1318  case Module::AppendUnique: {
1320  MDNode *DstValue = cast<MDNode>(DstOp->getOperand(2));
1321  MDNode *SrcValue = cast<MDNode>(SrcOp->getOperand(2));
1322  Elts.insert(DstValue->op_begin(), DstValue->op_end());
1323  Elts.insert(SrcValue->op_begin(), SrcValue->op_end());
1324 
1325  replaceDstValue(MDNode::get(DstM.getContext(),
1326  makeArrayRef(Elts.begin(), Elts.end())));
1327  break;
1328  }
1329  }
1330  }
1331 
1332  // Check all of the requirements.
1333  for (unsigned I = 0, E = Requirements.size(); I != E; ++I) {
1334  MDNode *Requirement = Requirements[I];
1335  MDString *Flag = cast<MDString>(Requirement->getOperand(0));
1336  Metadata *ReqValue = Requirement->getOperand(1);
1337 
1338  MDNode *Op = Flags[Flag].first;
1339  if (!Op || Op->getOperand(2) != ReqValue)
1340  return stringErr("linking module flags '" + Flag->getString() +
1341  "': does not have the required value");
1342  }
1343  return Error::success();
1344 }
1345 
1346 /// Return InlineAsm adjusted with target-specific directives if required.
1347 /// For ARM and Thumb, we have to add directives to select the appropriate ISA
1348 /// to support mixing module-level inline assembly from ARM and Thumb modules.
1349 static std::string adjustInlineAsm(const std::string &InlineAsm,
1350  const Triple &Triple) {
1351  if (Triple.getArch() == Triple::thumb || Triple.getArch() == Triple::thumbeb)
1352  return ".text\n.balign 2\n.thumb\n" + InlineAsm;
1353  if (Triple.getArch() == Triple::arm || Triple.getArch() == Triple::armeb)
1354  return ".text\n.balign 4\n.arm\n" + InlineAsm;
1355  return InlineAsm;
1356 }
1357 
1358 Error IRLinker::run() {
1359  // Ensure metadata materialized before value mapping.
1360  if (SrcM->getMaterializer())
1361  if (Error Err = SrcM->getMaterializer()->materializeMetadata())
1362  return Err;
1363 
1364  // Inherit the target data from the source module if the destination module
1365  // doesn't have one already.
1366  if (DstM.getDataLayout().isDefault())
1367  DstM.setDataLayout(SrcM->getDataLayout());
1368 
1369  if (SrcM->getDataLayout() != DstM.getDataLayout()) {
1370  emitWarning("Linking two modules of different data layouts: '" +
1371  SrcM->getModuleIdentifier() + "' is '" +
1372  SrcM->getDataLayoutStr() + "' whereas '" +
1373  DstM.getModuleIdentifier() + "' is '" +
1374  DstM.getDataLayoutStr() + "'\n");
1375  }
1376 
1377  // Copy the target triple from the source to dest if the dest's is empty.
1378  if (DstM.getTargetTriple().empty() && !SrcM->getTargetTriple().empty())
1379  DstM.setTargetTriple(SrcM->getTargetTriple());
1380 
1381  Triple SrcTriple(SrcM->getTargetTriple()), DstTriple(DstM.getTargetTriple());
1382 
1383  if (!SrcM->getTargetTriple().empty()&&
1384  !SrcTriple.isCompatibleWith(DstTriple))
1385  emitWarning("Linking two modules of different target triples: " +
1386  SrcM->getModuleIdentifier() + "' is '" +
1387  SrcM->getTargetTriple() + "' whereas '" +
1388  DstM.getModuleIdentifier() + "' is '" + DstM.getTargetTriple() +
1389  "'\n");
1390 
1391  DstM.setTargetTriple(SrcTriple.merge(DstTriple));
1392 
1393  // Append the module inline asm string.
1394  if (!IsPerformingImport && !SrcM->getModuleInlineAsm().empty()) {
1395  std::string SrcModuleInlineAsm = adjustInlineAsm(SrcM->getModuleInlineAsm(),
1396  SrcTriple);
1397  if (DstM.getModuleInlineAsm().empty())
1398  DstM.setModuleInlineAsm(SrcModuleInlineAsm);
1399  else
1400  DstM.setModuleInlineAsm(DstM.getModuleInlineAsm() + "\n" +
1401  SrcModuleInlineAsm);
1402  }
1403 
1404  // Loop over all of the linked values to compute type mappings.
1405  computeTypeMapping();
1406 
1407  std::reverse(Worklist.begin(), Worklist.end());
1408  while (!Worklist.empty()) {
1409  GlobalValue *GV = Worklist.back();
1410  Worklist.pop_back();
1411 
1412  // Already mapped.
1413  if (ValueMap.find(GV) != ValueMap.end() ||
1414  AliasValueMap.find(GV) != AliasValueMap.end())
1415  continue;
1416 
1417  assert(!GV->isDeclaration());
1418  Mapper.mapValue(*GV);
1419  if (FoundError)
1420  return std::move(*FoundError);
1421  flushRAUWWorklist();
1422  }
1423 
1424  // Note that we are done linking global value bodies. This prevents
1425  // metadata linking from creating new references.
1426  DoneLinkingBodies = true;
1427  Mapper.addFlags(RF_NullMapMissingGlobalValues);
1428 
1429  // Remap all of the named MDNodes in Src into the DstM module. We do this
1430  // after linking GlobalValues so that MDNodes that reference GlobalValues
1431  // are properly remapped.
1432  linkNamedMDNodes();
1433 
1434  // Merge the module flags into the DstM module.
1435  return linkModuleFlagsMetadata();
1436 }
1437 
1439  : ETypes(E), IsPacked(P) {}
1440 
1442  : ETypes(ST->elements()), IsPacked(ST->isPacked()) {}
1443 
1445  return IsPacked == That.IsPacked && ETypes == That.ETypes;
1446 }
1447 
1449  return !this->operator==(That);
1450 }
1451 
1452 StructType *IRMover::StructTypeKeyInfo::getEmptyKey() {
1454 }
1455 
1456 StructType *IRMover::StructTypeKeyInfo::getTombstoneKey() {
1458 }
1459 
1460 unsigned IRMover::StructTypeKeyInfo::getHashValue(const KeyTy &Key) {
1461  return hash_combine(hash_combine_range(Key.ETypes.begin(), Key.ETypes.end()),
1462  Key.IsPacked);
1463 }
1464 
1465 unsigned IRMover::StructTypeKeyInfo::getHashValue(const StructType *ST) {
1466  return getHashValue(KeyTy(ST));
1467 }
1468 
1470  const StructType *RHS) {
1471  if (RHS == getEmptyKey() || RHS == getTombstoneKey())
1472  return false;
1473  return LHS == KeyTy(RHS);
1474 }
1475 
1477  const StructType *RHS) {
1478  if (RHS == getEmptyKey() || RHS == getTombstoneKey())
1479  return LHS == RHS;
1480  return KeyTy(LHS) == KeyTy(RHS);
1481 }
1482 
1484  assert(!Ty->isOpaque());
1485  NonOpaqueStructTypes.insert(Ty);
1486 }
1487 
1489  assert(!Ty->isOpaque());
1490  NonOpaqueStructTypes.insert(Ty);
1491  bool Removed = OpaqueStructTypes.erase(Ty);
1492  (void)Removed;
1493  assert(Removed);
1494 }
1495 
1497  assert(Ty->isOpaque());
1498  OpaqueStructTypes.insert(Ty);
1499 }
1500 
1501 StructType *
1503  bool IsPacked) {
1504  IRMover::StructTypeKeyInfo::KeyTy Key(ETypes, IsPacked);
1505  auto I = NonOpaqueStructTypes.find_as(Key);
1506  return I == NonOpaqueStructTypes.end() ? nullptr : *I;
1507 }
1508 
1510  if (Ty->isOpaque())
1511  return OpaqueStructTypes.count(Ty);
1512  auto I = NonOpaqueStructTypes.find(Ty);
1513  return I == NonOpaqueStructTypes.end() ? false : *I == Ty;
1514 }
1515 
1516 IRMover::IRMover(Module &M) : Composite(M) {
1517  TypeFinder StructTypes;
1518  StructTypes.run(M, /* OnlyNamed */ false);
1519  for (StructType *Ty : StructTypes) {
1520  if (Ty->isOpaque())
1521  IdentifiedStructTypes.addOpaque(Ty);
1522  else
1523  IdentifiedStructTypes.addNonOpaque(Ty);
1524  }
1525  // Self-map metadatas in the destination module. This is needed when
1526  // DebugTypeODRUniquing is enabled on the LLVMContext, since metadata in the
1527  // destination module may be reached from the source module.
1528  for (auto *MD : StructTypes.getVisitedMetadata()) {
1529  SharedMDs[MD].reset(const_cast<MDNode *>(MD));
1530  }
1531 }
1532 
1534  std::unique_ptr<Module> Src, ArrayRef<GlobalValue *> ValuesToLink,
1535  std::function<void(GlobalValue &, ValueAdder Add)> AddLazyFor,
1536  bool IsPerformingImport) {
1537  IRLinker TheIRLinker(Composite, SharedMDs, IdentifiedStructTypes,
1538  std::move(Src), ValuesToLink, std::move(AddLazyFor),
1539  IsPerformingImport);
1540  Error E = TheIRLinker.run();
1541  Composite.dropTriviallyDeadConstantArrays();
1542  return E;
1543 }
bool isDeclarationForLinker() const
Definition: GlobalValue.h:533
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:641
ThreadLocalMode getThreadLocalMode() const
Definition: GlobalValue.h:258
static MDTuple * get(LLVMContext &Context, ArrayRef< Metadata *> MDs)
Definition: Metadata.h:1132
bool hasLocalLinkage() const
Definition: GlobalValue.h:445
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:1438
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:65
iterator end()
Definition: Function.h:682
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:632
Externally visible function.
Definition: GlobalValue.h:48
LLVMContext & getContext() const
All values hold a context through their type.
Definition: Value.cpp:732
bool hasPrologueData() const
Check whether this function has prologue data.
Definition: Function.h:744
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:580
void switchToNonOpaque(StructType *Ty)
Definition: IRMover.cpp:1488
bool isOpaque() const
Return true if this is a type with an identity that has no body specified yet.
Definition: DerivedTypes.h:301
bool hasExternalWeakLinkage() const
Definition: GlobalValue.h:446
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:116
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
bool hasAttribute(unsigned Index, Attribute::AttrKind Kind) const
Return true if the attribute exists at the given index.
Constant * getPrologueData() const
Get the prologue data associated with this function.
Definition: Function.cpp:1404
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:735
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:233
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
For scalable vectors, this will return the minimum number of elements in the vector.
Definition: DerivedTypes.h:393
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:1394
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:273
Key
PAL metadata keys.
llvm::Optional< Function * > remangleIntrinsicFunction(Function *F)
Definition: Function.cpp:1308
Class to represent function types.
Definition: DerivedTypes.h:103
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:1533
ArchType getArch() const
getArch - Get the parsed architecture type of this triple.
Definition: Triple.h:296
Class to represent array types.
Definition: DerivedTypes.h:403
Type * getValueAsType() const
Return the attribute&#39;s value as a Type.
Definition: Attributes.cpp:230
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:1448
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:726
LinkageTypes getLinkage() const
Definition: GlobalValue.h:460
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
constexpr char Attrs[]
Key for Kernel::Metadata::mAttrs.
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:544
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:442
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:313
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:236
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
This is an important class for using LLVM in a threaded context.
Definition: LLVMContext.h:64
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
static Attribute getWithByValType(LLVMContext &Context, Type *Ty)
Definition: Attributes.cpp:170
unsigned getAddressSpace() const
Return the address space of the Pointer type.
Definition: DerivedTypes.h:572
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:1232
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:434
Attribute getAttribute(unsigned Index, Attribute::AttrKind Kind) const
Return the attribute object that exists at the given index.
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:810
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:837
CHAIN = SC CHAIN, Imm128 - System call.
bool hasGlobalUnnamedAddr() const
Definition: GlobalValue.h:203
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:1444
void setLinkage(LinkageTypes LT)
Definition: GlobalValue.h:454
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:297
static StringRef getTypeNamePrefix(StringRef Name)
Definition: IRMover.cpp:721
const Comdat * getComdat() const
Definition: Globals.cpp:171
unsigned getNumAttrSets() const
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:1516
void eraseFromParent()
This method unlinks &#39;this&#39; from the containing module and deletes it.
Definition: Globals.cpp:85
LLVM_NODISCARD AttributeList addAttribute(LLVMContext &C, unsigned Index, Attribute::AttrKind Kind) const
Add an attribute to the attribute set at the given index.
bool isPacked() const
Definition: DerivedTypes.h:293
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
static VectorType * get(Type *ElementType, ElementCount EC)
This static method is the primary way to construct an VectorType.
Definition: Type.cpp:609
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:407
LLVM_NODISCARD AttributeList removeAttribute(LLVMContext &C, unsigned Index, Attribute::AttrKind Kind) const
Remove the specified attribute at the specified index from this attribute list.
#define I(x, y, z)
Definition: MD5.cpp:58
void setPrologueData(Constant *PrologueData)
Definition: Function.cpp:1409
static ArrayType * get(Type *ElementType, uint64_t NumElements)
This static method is the primary way to construct an ArrayType.
Definition: Type.cpp:582
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:279
const BasicBlockListType & getBasicBlockList() const
Get the underlying elements of the Function...
Definition: Function.h:657
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:227
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:1502
Module * getParent()
Get the module that this global value is contained inside of...
Definition: GlobalValue.h:575
LLVM Value Representation.
Definition: Value.h:72
Constant * getPersonalityFn() const
Get the personality function associated with this function.
Definition: Function.cpp:1384
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:1349
static void forceRenaming(GlobalValue *GV, StringRef Name)
The LLVM SymbolTable class autorenames globals that conflict in the symbol table. ...
Definition: IRMover.cpp:545
Type * getElementType() const
Definition: DerivedTypes.h:394
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:1389
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:307
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:444
PointerType * getType() const
Global values are always pointers.
Definition: GlobalValue.h:277
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:1399
void resize(size_type N)
Definition: SmallVector.h:344
const Constant * getAliasee() const
Definition: GlobalAlias.h:77