C++ NamedDecl::setDeclContext方法代码示例

  bool DeclExtractor::ExtractDecl(FunctionDecl* FD) {
    llvm::SmallVector<NamedDecl*, 4> TouchedDecls;
    CompoundStmt* CS = dyn_cast<CompoundStmt>(FD->getBody());
    assert(CS && "Function body not a CompoundStmt?");
    DeclContext* DC = FD->getTranslationUnitDecl();
    Scope* TUScope = m_Sema->TUScope;
    assert(TUScope == m_Sema->getScopeForContext(DC) && "TU scope from DC?");
    llvm::SmallVector<Stmt*, 4> Stmts;

    for (CompoundStmt::body_iterator I = CS->body_begin(), EI = CS->body_end();
         I != EI; ++I) {
      DeclStmt* DS = dyn_cast<DeclStmt>(*I);
      if (!DS) {
        Stmts.push_back(*I);
        continue;
      }
      
      for (DeclStmt::decl_iterator J = DS->decl_begin();
           J != DS->decl_end(); ++J) {
        NamedDecl* ND = dyn_cast<NamedDecl>(*J);
        if (isa<UsingDirectiveDecl>(*J))
          continue; // FIXME: Here we should be more elegant.
        if (ND) {
          if (Stmts.size()) {
            // We need to emit a new custom wrapper wrapping the stmts
            EnforceInitOrder(Stmts);
            assert(!Stmts.size() && "Stmt list must be flushed.");
          }

          // We know the transaction is closed, but it is safe.
          getTransaction()->forceAppend(ND);

          DeclContext* OldDC = ND->getDeclContext();

          // Make sure the decl is not found at its old possition
          ND->getLexicalDeclContext()->removeDecl(ND);
          if (Scope* S = m_Sema->getScopeForContext(OldDC)) {
            S->RemoveDecl(ND);
            if (utils::Analyze::isOnScopeChains(ND, *m_Sema))
              m_Sema->IdResolver.RemoveDecl(ND);
          }

          // For variable definitions causing var/function ambiguity such as:
          // MyClass my();, C++ standard says it shall be resolved as a function
          //
          // In the particular context this definition is inside a function
          // already, but clang thinks it as a lambda, so we need to ignore the
          // check decl context vs lexical decl context.
          if (ND->getDeclContext() == ND->getLexicalDeclContext()
              || isa<FunctionDecl>(ND))
            ND->setLexicalDeclContext(DC);
          else 
            assert(0 && "Not implemented: Decl with different lexical context");
          ND->setDeclContext(DC);

          if (VarDecl* VD = dyn_cast<VarDecl>(ND)) {
            VD->setStorageClass(SC_None);
          }

          clearLinkage(ND);

          TouchedDecls.push_back(ND);
        }
      }
    }
    bool hasNoErrors = !CheckForClashingNames(TouchedDecls, DC, TUScope);
    if (hasNoErrors) {
      for (size_t i = 0; i < TouchedDecls.size(); ++i) {
        // We should skip the checks for annonymous decls and we should not
        // register them in the lookup.
        if (!TouchedDecls[i]->getDeclName())
          continue;

        m_Sema->PushOnScopeChains(TouchedDecls[i],
                                  m_Sema->getScopeForContext(DC),
                    /*AddCurContext*/!isa<UsingDirectiveDecl>(TouchedDecls[i]));

        // The transparent DeclContexts (eg. scopeless enum) doesn't have 
        // scopes. While extracting their contents we need to update the
        // lookup tables and telling them to pick up the new possitions
        // in the AST.
        if (DeclContext* InnerDC = dyn_cast<DeclContext>(TouchedDecls[i])) {
          if (InnerDC->isTransparentContext()) {
            // We can't PushDeclContext, because we don't have scope.
            Sema::ContextRAII pushedDC(*m_Sema, InnerDC);

            for(DeclContext::decl_iterator DI = InnerDC->decls_begin(), 
                  DE = InnerDC->decls_end(); DI != DE ; ++DI) {
              if (NamedDecl* ND = dyn_cast<NamedDecl>(*DI))
                InnerDC->makeDeclVisibleInContext(ND);
            }
          }
        }
      }
    }

    CS->setStmts(*m_Context, Stmts.data(), Stmts.size());

    // The order matters, because when we extract decls from the wrapper we
    // append them to the transaction. If the transaction gets unloaded it will
//.........这里部分代码省略.........

  bool DeclExtractor::ExtractDecl(Decl* D) {
    FunctionDecl* FD = dyn_cast<FunctionDecl>(D);

    if (FD) {
      if (FD->getNameAsString().find("__cling_Un1Qu3"))
        return true;

      llvm::SmallVector<NamedDecl*, 4> TouchedDecls;
      CompoundStmt* CS = dyn_cast<CompoundStmt>(FD->getBody());
      assert(CS && "Function body not a CompoundStmt?");
      DeclContext* DC = FD->getTranslationUnitDecl();
      Scope* TUScope = m_Sema->TUScope;
      assert(TUScope == m_Sema->getScopeForContext(DC) && "TU scope from DC?");
      llvm::SmallVector<Stmt*, 4> Stmts;

      for (CompoundStmt::body_iterator I = CS->body_begin(), EI = CS->body_end();
           I != EI; ++I) {
        DeclStmt* DS = dyn_cast<DeclStmt>(*I);
        if (!DS) {
          Stmts.push_back(*I);
          continue;
        }

        for (DeclStmt::decl_iterator J = DS->decl_begin();
             J != DS->decl_end(); ++J) {
          NamedDecl* ND = dyn_cast<NamedDecl>(*J);
          if (ND) {
            DeclContext* OldDC = ND->getDeclContext();

            // Make sure the decl is not found at its old possition
            OldDC->removeDecl(ND);
            if (Scope* S = m_Sema->getScopeForContext(OldDC)) {
              S->RemoveDecl(ND);
              m_Sema->IdResolver.RemoveDecl(ND);
            }

            if (ND->getDeclContext() == ND->getLexicalDeclContext())
              ND->setLexicalDeclContext(DC);
            else 
              assert("Not implemented: Decl with different lexical context");
            ND->setDeclContext(DC);

            if (VarDecl* VD = dyn_cast<VarDecl>(ND)) {
              VD->setStorageClass(SC_None);
              VD->setStorageClassAsWritten(SC_None);

              // if we want to print the result of the initializer of int i = 5
              // or the default initializer int i
              if (I+1 == EI || !isa<NullStmt>(*(I+1))) {
                QualType VDTy = VD->getType().getNonReferenceType();
                Expr* DRE = m_Sema->BuildDeclRefExpr(VD, VDTy,VK_LValue,
                                                     SourceLocation()
                                                     ).take();
                Stmts.push_back(DRE);
              }
            }
            // force recalc of the linkage (to external)
            ND->ClearLinkageCache();

            TouchedDecls.push_back(ND);
          }
        }
      }
      bool hasNoErrors = !CheckForClashingNames(TouchedDecls, DC, TUScope);
      if (hasNoErrors) {
        for (size_t i = 0; i < TouchedDecls.size(); ++i) {
          m_Sema->PushOnScopeChains(TouchedDecls[i],
                                    m_Sema->getScopeForContext(DC),
                    /*AddCurContext*/!isa<UsingDirectiveDecl>(TouchedDecls[i]));

          // The transparent DeclContexts (eg. scopeless enum) doesn't have 
          // scopes. While extracting their contents we need to update the
          // lookup tables and telling them to pick up the new possitions
          //  in the AST.
          if (DeclContext* InnerDC = dyn_cast<DeclContext>(TouchedDecls[i])) {
            if (InnerDC->isTransparentContext()) {
              // We can't PushDeclContext, because we don't have scope.
              Sema::ContextRAII pushedDC(*m_Sema, InnerDC);

              for(DeclContext::decl_iterator DI = InnerDC->decls_begin(), 
                    DE = InnerDC->decls_end(); DI != DE ; ++DI) {
                if (NamedDecl* ND = dyn_cast<NamedDecl>(*DI))
                  InnerDC->makeDeclVisibleInContext(ND);
              }
            }
          }

          // Append the new top level decl to the current transaction.
          getTransaction()->appendUnique(DeclGroupRef(TouchedDecls[i]));
        }
      }

      CS->setStmts(*m_Context, Stmts.data(), Stmts.size());

      // Put the wrapper after its declarations. (Nice when AST dumping)
      DC->removeDecl(FD);
      DC->addDecl(FD);

      return hasNoErrors;
    }
//.........这里部分代码省略.........