From 63aa2fbec61b9c31dd388bf54d92a1b42d34d959 Mon Sep 17 00:00:00 2001
From: David Majnemer <david.majnemer@gmail.com>
Date: Tue, 30 Jun 2015 21:23:51 +0000
Subject: [PATCH] [MS ABI] Stick constructor closures in an IR COMDAT group

We no-longer stick linkonce_odr entities in COMDATs in the backend.
Instead, we rely on the IR COMDAT mechanism.

llvm-svn: 241117
---
 clang/lib/CodeGen/MicrosoftCXXABI.cpp |  2 ++
 clang/test/CodeGenCXX/dllexport.cpp   | 12 ++++++------
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/clang/lib/CodeGen/MicrosoftCXXABI.cpp b/clang/lib/CodeGen/MicrosoftCXXABI.cpp
index afababe..d149df6 100644
--- a/clang/lib/CodeGen/MicrosoftCXXABI.cpp
+++ b/clang/lib/CodeGen/MicrosoftCXXABI.cpp
@@ -3732,6 +3732,8 @@ MicrosoftCXXABI::getAddrOfCXXCtorClosure(const CXXConstructorDecl *CD,
       ThunkTy, getLinkageForRTTI(RecordTy), ThunkName.str(), &CGM.getModule());
   ThunkFn->setCallingConv(static_cast<llvm::CallingConv::ID>(
       FnInfo.getEffectiveCallingConvention()));
+  if (ThunkFn->isWeakForLinker())
+    ThunkFn->setComdat(CGM.getModule().getOrInsertComdat(ThunkFn->getName()));
   bool IsCopy = CT == Ctor_CopyingClosure;
 
   // Start codegen.
diff --git a/clang/test/CodeGenCXX/dllexport.cpp b/clang/test/CodeGenCXX/dllexport.cpp
index 0eb6476..c598880 100644
--- a/clang/test/CodeGenCXX/dllexport.cpp
+++ b/clang/test/CodeGenCXX/dllexport.cpp
@@ -486,7 +486,7 @@ struct S {
 
 struct CtorWithClosure {
   __declspec(dllexport) CtorWithClosure(...) {}
-// M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??_FCtorWithClosure@@QAEXXZ"
+// M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??_FCtorWithClosure@@QAEXXZ"({{.*}}) comdat
 // M32-DAG:   %[[this_addr:.*]] = alloca %struct.CtorWithClosure*, align 4
 // M32-DAG:   store %struct.CtorWithClosure* %this, %struct.CtorWithClosure** %[[this_addr]], align 4
 // M32-DAG:   %[[this:.*]] = load %struct.CtorWithClosure*, %struct.CtorWithClosure** %[[this_addr]]
@@ -503,7 +503,7 @@ struct CtorWithClosure {
 struct __declspec(dllexport) ClassWithClosure {
   DELETE_IMPLICIT_MEMBERS(ClassWithClosure);
   ClassWithClosure(...) {}
-// M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??_FClassWithClosure@@QAEXXZ"
+// M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??_FClassWithClosure@@QAEXXZ"({{.*}}) comdat
 // M32-DAG:   %[[this_addr:.*]] = alloca %struct.ClassWithClosure*, align 4
 // M32-DAG:   store %struct.ClassWithClosure* %this, %struct.ClassWithClosure** %[[this_addr]], align 4
 // M32-DAG:   %[[this:.*]] = load %struct.ClassWithClosure*, %struct.ClassWithClosure** %[[this_addr]]
@@ -520,8 +520,8 @@ struct __declspec(dllexport) NestedOuter {
   };
 };
 
-// M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??_FNestedOuter@@QAEXXZ"
-// M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??_FNestedInner@NestedOuter@@QAEXXZ"
+// M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??_FNestedOuter@@QAEXXZ"({{.*}}) comdat
+// M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??_FNestedInner@NestedOuter@@QAEXXZ"({{.*}}) comdat
 
 template <typename T>
 struct SomeTemplate {
@@ -530,7 +530,7 @@ struct SomeTemplate {
 };
 struct __declspec(dllexport) InheritFromTemplate : SomeTemplate<int> {};
 
-// M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??_F?$SomeTemplate@H@@QAEXXZ"
+// M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??_F?$SomeTemplate@H@@QAEXXZ"({{.*}}) comdat
 
 namespace PR23801 {
 template <typename>
@@ -546,7 +546,7 @@ struct __declspec(dllexport) B {
 };
 }
 //
-// M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??_FB@PR23801@@QAEXXZ"
+// M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??_FB@PR23801@@QAEXXZ"({{.*}}) comdat
 
 struct __declspec(dllexport) T {
   // Copy assignment operator:
-- 
2.7.4