Commit 85c74384 authored by Tyker's avatar Tyker
Browse files

[clang][modules] Add support for merging lifetime-extended temporaries 

Summary: Add support for merging lifetime-extended temporaries

Reviewers: rsmith

Reviewed By: rsmith

Subscribers: xbolva00, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D70190
parent 8682d29a

clang/include/clang/AST/DeclCXX.h

+3 −1
Original line number Diff line number Diff line
@@ -3041,7 +3041,9 @@ public: 


/// Implicit declaration of a temporary that was materialized by

/// a MaterializeTemporaryExpr and lifetime-extended by a declaration

class LifetimeExtendedTemporaryDecl final : public Decl {

class LifetimeExtendedTemporaryDecl final

    : public Decl,

      public Mergeable<LifetimeExtendedTemporaryDecl> {

  friend class MaterializeTemporaryExpr;

  friend class ASTDeclReader;

clang/include/clang/AST/TextNodeDumper.h

+2 −0
Original line number Diff line number Diff line
@@ -346,6 +346,8 @@ public: 
  void VisitObjCPropertyImplDecl(const ObjCPropertyImplDecl *D);

  void VisitBlockDecl(const BlockDecl *D);

  void VisitConceptDecl(const ConceptDecl *D);

  void

  VisitLifetimeExtendedTemporaryDecl(const LifetimeExtendedTemporaryDecl *D);

};



} // namespace clang

clang/include/clang/Serialization/ASTReader.h

+8 −0
Original line number Diff line number Diff line
@@ -551,6 +551,14 @@ private: 
  llvm::DenseMap<Decl*, llvm::SmallVector<NamedDecl*, 2>>

    AnonymousDeclarationsForMerging;



  /// Key used to identify LifetimeExtendedTemporaryDecl for merging,

  /// containing the lifetime-extending declaration and the mangling number.

  using LETemporaryKey = std::pair<Decl *, unsigned>;



  /// Map of already deserialiazed temporaries.

  llvm::DenseMap<LETemporaryKey, LifetimeExtendedTemporaryDecl *>

      LETemporaryForMerging;



  struct FileDeclsInfo {

    ModuleFile *Mod = nullptr;

    ArrayRef<serialization::LocalDeclID> Decls;

clang/lib/AST/TextNodeDumper.cpp

+11 −0
Original line number Diff line number Diff line
@@ -1338,6 +1338,17 @@ void TextNodeDumper::VisitFunctionDecl(const FunctionDecl *D) { 
    OS << " <<<NULL params x " << D->getNumParams() << ">>>";

}



void TextNodeDumper::VisitLifetimeExtendedTemporaryDecl(

    const LifetimeExtendedTemporaryDecl *D) {

  OS << " extended by ";

  dumpBareDeclRef(D->getExtendingDecl());

  OS << " mangling ";

  {

    ColorScope Color(OS, ShowColors, ValueColor);

    OS << D->getManglingNumber();

  }

}



void TextNodeDumper::VisitFieldDecl(const FieldDecl *D) {

  dumpName(D);

  dumpType(D->getType());

clang/lib/Serialization/ASTReaderDecl.cpp

+22 −0
Original line number Diff line number Diff line
@@ -424,6 +424,8 @@ namespace clang { 
    template<typename T>

    void mergeMergeable(Mergeable<T> *D);



    void mergeMergeable(LifetimeExtendedTemporaryDecl *D);



    void mergeTemplatePattern(RedeclarableTemplateDecl *D,

                              RedeclarableTemplateDecl *Existing,

                              DeclID DsID, bool IsKeyDecl);
@@ -2358,6 +2360,7 @@ void ASTDeclReader::VisitLifetimeExtendedTemporaryDecl( 
  if (Record.readInt())

    D->Value = new (D->getASTContext()) APValue(Record.readAPValue());

  D->ManglingNumber = Record.readInt();

  mergeMergeable(D);

}



std::pair<uint64_t, uint64_t>
@@ -2555,6 +2558,25 @@ static bool allowODRLikeMergeInC(NamedDecl *ND) { 
  return false;

}



/// Attempts to merge LifetimeExtendedTemporaryDecl with

/// identical class definitions from two different modules.

void ASTDeclReader::mergeMergeable(LifetimeExtendedTemporaryDecl *D) {

  // If modules are not available, there is no reason to perform this merge.

  if (!Reader.getContext().getLangOpts().Modules)

    return;



  LifetimeExtendedTemporaryDecl *LETDecl = D;



  LifetimeExtendedTemporaryDecl *&LookupResult =

      Reader.LETemporaryForMerging[std::make_pair(

          LETDecl->getExtendingDecl(), LETDecl->getManglingNumber())];

  if (LookupResult)

    Reader.getContext().setPrimaryMergedDecl(LETDecl,

                                             LookupResult->getCanonicalDecl());

  else

    LookupResult = LETDecl;

}



/// Attempts to merge the given declaration (D) with another declaration

/// of the same entity, for the case where the entity is not actually

/// redeclarable. This happens, for instance, when merging the fields of