From fa27e41eb8de3f91ee3901e8de30df57449fabcc Mon Sep 17 00:00:00 2001
From: Shoaib Meenai <smeenai@fb.com>
Date: Tue, 4 Jul 2017 01:02:19 +0000
Subject: [PATCH] [CodeGen] Check key function for typeinfo import

If the imported class does not have a key function, we should emit its
typeinfo locally instead of attempting to import it.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@307052 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/ItaniumCXXABI.cpp                 | 10 +++++++---
 test/CodeGenCXX/windows-itanium-type-info.cpp | 10 ++++++++--
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/lib/CodeGen/ItaniumCXXABI.cpp b/lib/CodeGen/ItaniumCXXABI.cpp
index 39efb9f439..e6d38aff34 100644
--- a/lib/CodeGen/ItaniumCXXABI.cpp
+++ b/lib/CodeGen/ItaniumCXXABI.cpp
@@ -2732,7 +2732,9 @@ static bool ShouldUseExternalRTTIDescriptor(CodeGenModule &CGM,
     // function.
     bool IsDLLImport = RD->hasAttr<DLLImportAttr>();
     if (CGM.getVTables().isVTableExternal(RD))
-      return IsDLLImport ? false : true;
+      return IsDLLImport && !CGM.getTriple().isWindowsItaniumEnvironment()
+                 ? false
+                 : true;
 
     if (IsDLLImport)
       return true;
@@ -2968,7 +2970,8 @@ static llvm::GlobalVariable::LinkageTypes getTypeInfoLinkage(CodeGenModule &CGM,
       if (RD->hasAttr<WeakAttr>())
         return llvm::GlobalValue::WeakODRLinkage;
       if (CGM.getTriple().isWindowsItaniumEnvironment())
-        if (RD->hasAttr<DLLImportAttr>())
+        if (RD->hasAttr<DLLImportAttr>() &&
+            ShouldUseExternalRTTIDescriptor(CGM, Ty))
           return llvm::GlobalValue::ExternalLinkage;
       if (RD->isDynamicClass()) {
         llvm::GlobalValue::LinkageTypes LT = CGM.getVTableLinkage(RD);
@@ -3181,7 +3184,8 @@ llvm::Constant *ItaniumRTTIBuilder::BuildTypeInfo(QualType Ty, bool Force,
     if (DLLExport || (RD && RD->hasAttr<DLLExportAttr>())) {
       TypeName->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
       GV->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
-    } else if (CGM.getLangOpts().RTTI && RD && RD->hasAttr<DLLImportAttr>()) {
+    } else if (RD && RD->hasAttr<DLLImportAttr>() &&
+               ShouldUseExternalRTTIDescriptor(CGM, Ty)) {
       TypeName->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
       GV->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
 
diff --git a/test/CodeGenCXX/windows-itanium-type-info.cpp b/test/CodeGenCXX/windows-itanium-type-info.cpp
index ad89318f59..285b59815d 100644
--- a/test/CodeGenCXX/windows-itanium-type-info.cpp
+++ b/test/CodeGenCXX/windows-itanium-type-info.cpp
@@ -32,9 +32,15 @@ void f() {
 // CHECK-DAG: @_ZTV7derived = dllexport unnamed_addr constant
 
 // CHECK-DAG: @_ZTI4base = external dllimport constant
-// CHECK-DAG: @_ZTS4base = external dllimport constant
-// CHECK-NOT: @_ZTV4base = external dllimport constant
 
 // CHECK-EH-IMPORT: @_ZTS4base = linkonce_odr constant
 // CHECK-EH-IMPORT: @_ZTI4base = linkonce_odr constant
 
+struct __declspec(dllimport) gatekeeper {};
+struct zuul : gatekeeper {
+  virtual ~zuul();
+};
+zuul::~zuul() {}
+
+// CHECK-DAG: @_ZTI10gatekeeper = linkonce_odr constant
+// CHECK-DAG: @_ZTS10gatekeeper = linkonce_odr constant
-- 
2.40.0