PR13941: Mark all virtual functions as unnamed_addr. It's not possible to

observe their addresses (taking their address gives the vtable slot) so we are
free to merge their definitions.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@164864 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index 164031a50384808402e8cdd73c8c1e6ed743a049..d09c1c32606a9e3f0bb4e96bb4b81a1dc2a3b5b4 100644 (file)
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -588,6 +588,10 @@ void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
   if (isa<CXXConstructorDecl>(D) || isa<CXXDestructorDecl>(D))
     F->setUnnamedAddr(true);
 
+  if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D))
+    if (MD->isVirtual())
+      F->setUnnamedAddr(true);
+
   if (LangOpts.getStackProtector() == LangOptions::SSPOn)
     F->addFnAttr(llvm::Attribute::StackProtect);
   else if (LangOpts.getStackProtector() == LangOptions::SSPReq)

diff --git a/test/CodeGenCXX/attr.cpp b/test/CodeGenCXX/attr.cpp
index 9e8740e54700bfaf4e2d185f559001907305d53f..a0dd748601340aec8bc718c068ce11352ff90f12 100644 (file)
--- a/test/CodeGenCXX/attr.cpp
+++ b/test/CodeGenCXX/attr.cpp
@@ -10,17 +10,21 @@ class C {
   virtual void bar1() __attribute__((aligned(1)));
   virtual void bar2() __attribute__((aligned(2)));
   virtual void bar3() __attribute__((aligned(1024)));
+  void bar4() __attribute__((aligned(1024)));
 } c;
 
-// CHECK: define void @_ZN1C4bar1Ev(%class.C* %this) nounwind align 2
+// CHECK: define void @_ZN1C4bar1Ev(%class.C* %this) unnamed_addr nounwind align 2
 void C::bar1() { }
 
-// CHECK: define void @_ZN1C4bar2Ev(%class.C* %this) nounwind align 2
+// CHECK: define void @_ZN1C4bar2Ev(%class.C* %this) unnamed_addr nounwind align 2
 void C::bar2() { }
 
-// CHECK: define void @_ZN1C4bar3Ev(%class.C* %this) nounwind align 1024
+// CHECK: define void @_ZN1C4bar3Ev(%class.C* %this) unnamed_addr nounwind align 1024
 void C::bar3() { }
 
+// CHECK: define void @_ZN1C4bar4Ev(%class.C* %this) nounwind align 1024
+void C::bar4() { }
+
 // PR6635
 // CHECK: define i32 @_Z5test1v()
 int test1() { return 10; }

diff --git a/test/CodeGenCXX/member-functions.cpp b/test/CodeGenCXX/member-functions.cpp
index b95763c0ffac300cbc8383113db6a20701efb38c..1310eb08d3d1a69fefe8ce532b78dc84c2b16924 100644 (file)
--- a/test/CodeGenCXX/member-functions.cpp
+++ b/test/CodeGenCXX/member-functions.cpp
@@ -35,6 +35,9 @@ struct S {
   static void g() { }
   
   static void f();
+
+  // RUN: grep "define linkonce_odr void @_ZN1S1vEv.*unnamed_addr" %t
+  virtual void v() {}
 };
 
 // RUN: grep "define void @_ZN1S1fEv" %t