commit b555a767baf4a1058bc6e4e05acbbee9e55d0e26
author Richard Smith <richard-llvm@metafoo.co.uk> Fri Sep 28 22:46:07 2012 +0000
committer Richard Smith <richard-llvm@metafoo.co.uk> Fri Sep 28 22:46:07 2012 +0000
tree f6da57e020a88e2bfcb717104ec4692ca21a9642
parent 538fe8f35b26b925e21a4329599c188d48264f0d

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.

llvm-svn: 164864

clang/lib/CodeGen/CodeGenModule.cpp

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 164031a..d09c1c3 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -588,6 +588,10 @@
   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)

clang/test/CodeGenCXX/attr.cpp

diff --git a/clang/test/CodeGenCXX/attr.cpp b/clang/test/CodeGenCXX/attr.cpp
index 9e8740e..a0dd748 100644
--- a/clang/test/CodeGenCXX/attr.cpp
+++ b/clang/test/CodeGenCXX/attr.cpp
@@ -10,17 +10,21 @@
   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; }

clang/test/CodeGenCXX/member-functions.cpp

diff --git a/clang/test/CodeGenCXX/member-functions.cpp b/clang/test/CodeGenCXX/member-functions.cpp
index b95763c..1310eb0 100644
--- a/clang/test/CodeGenCXX/member-functions.cpp
+++ b/clang/test/CodeGenCXX/member-functions.cpp
@@ -35,6 +35,9 @@
   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