From 0090140bef3e2c22de03f42c515f6de061103801 Mon Sep 17 00:00:00 2001
From: Reid Kleckner <reid@kleckner.net>
Date: Mon, 3 Feb 2014 18:54:51 +0000
Subject: [PATCH] [ms-cxxabi] Fix cast when structor replacement is an alias

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@200711 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/CodeGenModule.cpp                 | 12 +++++++----
 test/CodeGenCXX/destructors.cpp               |  7 +++++++
 .../microsoft-abi-structors-alias.cpp         | 21 +++++++++++++++++--
 3 files changed, 34 insertions(+), 6 deletions(-)

diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index 2ee232284f..c73e931c9d 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -187,10 +187,14 @@ void CodeGenModule::applyReplacements() {
     llvm::Function *OldF = cast<llvm::Function>(Entry);
     llvm::Function *NewF = dyn_cast<llvm::Function>(Replacement);
     if (!NewF) {
-      llvm::ConstantExpr *CE = cast<llvm::ConstantExpr>(Replacement);
-      assert(CE->getOpcode() == llvm::Instruction::BitCast ||
-             CE->getOpcode() == llvm::Instruction::GetElementPtr);
-      NewF = dyn_cast<llvm::Function>(CE->getOperand(0));
+      if (llvm::GlobalAlias *Alias = dyn_cast<llvm::GlobalAlias>(Replacement)) {
+        NewF = dyn_cast<llvm::Function>(Alias->getAliasedGlobal());
+      } else {
+        llvm::ConstantExpr *CE = cast<llvm::ConstantExpr>(Replacement);
+        assert(CE->getOpcode() == llvm::Instruction::BitCast ||
+               CE->getOpcode() == llvm::Instruction::GetElementPtr);
+        NewF = dyn_cast<llvm::Function>(CE->getOperand(0));
+      }
     }
 
     // Replace old with new, but keep the old order.
diff --git a/test/CodeGenCXX/destructors.cpp b/test/CodeGenCXX/destructors.cpp
index f0e5a124ee..9bd2754b91 100644
--- a/test/CodeGenCXX/destructors.cpp
+++ b/test/CodeGenCXX/destructors.cpp
@@ -6,6 +6,13 @@
 // CHECK-DAG: @_ZN5test11OD2Ev = alias {{.*}} @_ZN5test11AD2Ev
 // CHECK-DAG: @_ZN5test11SD2Ev = alias bitcast {{.*}} @_ZN5test11AD2Ev
 
+// WIN32-DAG: @_ZN5test01AD1Ev = alias {{.*}} @_ZN5test01AD2Ev
+// WIN32-DAG: @_ZN5test11MD2Ev = alias {{.*}} @_ZN5test11AD2Ev
+// WIN32-DAG: @_ZN5test11ND2Ev = alias {{.*}} @_ZN5test11AD2Ev
+// WIN32-DAG: @_ZN5test11OD2Ev = alias {{.*}} @_ZN5test11AD2Ev
+// WIN32-DAG: @_ZN5test11SD2Ev = alias bitcast {{.*}} @_ZN5test11AD2Ev
+
+
 struct A {
   int a;
   
diff --git a/test/CodeGenCXX/microsoft-abi-structors-alias.cpp b/test/CodeGenCXX/microsoft-abi-structors-alias.cpp
index 9301163d54..f977556aa5 100644
--- a/test/CodeGenCXX/microsoft-abi-structors-alias.cpp
+++ b/test/CodeGenCXX/microsoft-abi-structors-alias.cpp
@@ -1,9 +1,26 @@
-// RUN: %clang_cc1 -emit-llvm %s -o - -triple=i386-pc-win32 -fno-rtti -mconstructor-aliases | FileCheck %s
+// RUN: %clang_cc1 -emit-llvm %s -o - -triple=i386-pc-win32 -fno-rtti -mconstructor-aliases -O1 -disable-llvm-optzns | FileCheck %s
 
 namespace test1 {
 template <typename T> class A {
   ~A() {}
 };
 template class A<char>;
-// CHECK: define weak_odr x86_thiscallcc void @"\01??1?$A@D@test1@@AAE@XZ"
+// CHECK-DAG: define weak_odr x86_thiscallcc void @"\01??1?$A@D@test1@@AAE@XZ"
+}
+
+namespace test2 {
+struct A {
+  virtual ~A();
+};
+struct B : A {
+  B();
+  virtual ~B();
+};
+
+A::~A() {}
+B::~B() {}
+void foo() {
+  B b;
+}
+// CHECK-DAG: @"\01??1B@test2@@UAE@XZ" = alias bitcast (void (%"struct.test2::A"*)* @"\01??1A@test2@@UAE@XZ" to void (%"struct.test2::B"*)*)
 }
-- 
2.40.0