[ASTImporter] Support importing CXXUnresolvedConstructExpr and UnresolvedLookupExpr

* Note: This solution is based on
  https://github.com/haoNoQ/clang/blob/summary-ipa-draft/lib/AST/ASTImporter.cpp#L7605.

Patch by Peter Szecsi!

Differential Revision: https://reviews.llvm.org/D38694

llvm-svn: 322091

clang/lib/AST/ASTImporter.cpp

@@ -287,6 +287,8 @@ namespace clang {
     Expr *VisitCXXConstructExpr(CXXConstructExpr *E);
     Expr *VisitCXXMemberCallExpr(CXXMemberCallExpr *E);
     Expr *VisitCXXDependentScopeMemberExpr(CXXDependentScopeMemberExpr *E);
+    Expr *VisitCXXUnresolvedConstructExpr(CXXUnresolvedConstructExpr *CE);
+    Expr *VisitUnresolvedLookupExpr(UnresolvedLookupExpr *E);
     Expr *VisitExprWithCleanups(ExprWithCleanups *EWC);
     Expr *VisitCXXThisExpr(CXXThisExpr *E);
     Expr *VisitCXXBoolLiteralExpr(CXXBoolLiteralExpr *E);
@@ -5887,6 +5889,65 @@ Expr *ASTNodeImporter::VisitCXXDependentScopeMemberExpr(
       cast_or_null<NamedDecl>(ToFQ), MemberNameInfo, ResInfo);
 }
 
+Expr *ASTNodeImporter::VisitCXXUnresolvedConstructExpr(
+    CXXUnresolvedConstructExpr *CE) {
+
+  unsigned NumArgs = CE->arg_size();
+
+  llvm::SmallVector<Expr *, 8> ToArgs(NumArgs);
+  if (ImportArrayChecked(CE->arg_begin(), CE->arg_end(), ToArgs.begin()))
+    return nullptr;
+
+  return CXXUnresolvedConstructExpr::Create(
+      Importer.getToContext(), Importer.Import(CE->getTypeSourceInfo()),
+      Importer.Import(CE->getLParenLoc()), llvm::makeArrayRef(ToArgs),
+      Importer.Import(CE->getRParenLoc()));
+}
+
+Expr *ASTNodeImporter::VisitUnresolvedLookupExpr(UnresolvedLookupExpr *E) {
+  CXXRecordDecl *NamingClass =
+      cast_or_null<CXXRecordDecl>(Importer.Import(E->getNamingClass()));
+  if (E->getNamingClass() && !NamingClass)
+    return nullptr;
+
+  DeclarationName Name = Importer.Import(E->getName());
+  if (E->getName() && !Name)
+    return nullptr;
+
+  DeclarationNameInfo NameInfo(Name, Importer.Import(E->getNameLoc()));
+  // Import additional name location/type info.
+  ImportDeclarationNameLoc(E->getNameInfo(), NameInfo);
+
+  UnresolvedSet<8> ToDecls;
+  for (Decl *D : E->decls()) {
+    if (NamedDecl *To = cast_or_null<NamedDecl>(Importer.Import(D)))
+      ToDecls.addDecl(To);
+    else
+      return nullptr;
+  }
+
+  TemplateArgumentListInfo ToTAInfo(Importer.Import(E->getLAngleLoc()),
+                                    Importer.Import(E->getRAngleLoc()));
+  TemplateArgumentListInfo *ResInfo = nullptr;
+  if (E->hasExplicitTemplateArgs()) {
+    if (ImportTemplateArgumentListInfo(E->template_arguments(), ToTAInfo))
+      return nullptr;
+    ResInfo = &ToTAInfo;
+  }
+
+  if (ResInfo || E->getTemplateKeywordLoc().isValid())
+    return UnresolvedLookupExpr::Create(
+        Importer.getToContext(), NamingClass,
+        Importer.Import(E->getQualifierLoc()),
+        Importer.Import(E->getTemplateKeywordLoc()), NameInfo, E->requiresADL(),
+        ResInfo, ToDecls.begin(), ToDecls.end());
+
+  return UnresolvedLookupExpr::Create(
+      Importer.getToContext(), NamingClass,
+      Importer.Import(E->getQualifierLoc()), NameInfo, E->requiresADL(),
+      E->isOverloaded(), ToDecls.begin(), ToDecls.end());
+}
+
 Expr *ASTNodeImporter::VisitCallExpr(CallExpr *E) {
   QualType T = Importer.Import(E->getType());
   if (T.isNull())

clang/unittests/AST/ASTImporterTest.cpp

@@ -656,5 +656,40 @@ TEST(ImportDecl, ImportUsingShadowDecl) {
              namespaceDecl(has(usingShadowDecl())));
 }
 
+TEST(ImportExpr, ImportUnresolvedLookupExpr) {
+  MatchVerifier<Decl> Verifier;
+  testImport("template<typename T> int foo();"
+             "template <typename T> void declToImport() {"
+             "  ::foo<T>;"
+             "  ::template foo<T>;"
+             "}"
+             "void instantiate() { declToImport<int>(); }",
+             Lang_CXX, "", Lang_CXX, Verifier,
+             functionTemplateDecl(has(functionDecl(has(
+                 compoundStmt(has(unresolvedLookupExpr())))))));
+}
+
+TEST(ImportExpr, ImportCXXUnresolvedConstructExpr) {
+  MatchVerifier<Decl> Verifier;
+  testImport("template <typename T> class C { T t; };"
+             "template <typename T> void declToImport() {"
+             "  C<T> d;"
+             "  d.t = T();"
+             "}"
+             "void instantiate() { declToImport<int>(); }",
+             Lang_CXX, "", Lang_CXX, Verifier,
+             functionTemplateDecl(has(functionDecl(has(compoundStmt(has(
+                 binaryOperator(has(cxxUnresolvedConstructExpr())))))))));
+  testImport("template <typename T> class C { T t; };"
+             "template <typename T> void declToImport() {"
+             "  C<T> d;"
+             "  (&d)->t = T();"
+             "}"
+             "void instantiate() { declToImport<int>(); }",
+             Lang_CXX, "", Lang_CXX, Verifier,
+             functionTemplateDecl(has(functionDecl(has(compoundStmt(has(
+                 binaryOperator(has(cxxUnresolvedConstructExpr())))))))));
+}
+
 } // end namespace ast_matchers
 } // end namespace clang