CodeGen: Mark functions used in vtables as unnamed_addr.

This marks virtual function declarations, as well as runtime library functions
__cxa_pure_virtual, __cxa_deleted_virtual and _purecall, as unnamed_addr. This
will allow us to correctly form relative references to them from vtables in
the relative vtable ABI.

Differential Revision: http://reviews.llvm.org/D18071

llvm-svn: 263464

2 files changed, 10 insertions, 6 deletions

diff --git a/clang/lib/CodeGen/CGVTables.cpp b/clang/lib/CodeGen/CGVTables.cpp
index 953053bd1c3..f139e2c8504 100644
--- a/clang/lib/CodeGen/CGVTables.cpp
+++ b/clang/lib/CodeGen/CGVTables.cpp
@@ -607,6 +607,8 @@ llvm::Constant *CodeGenVTables::CreateVTableInitializer(
             llvm::FunctionType::get(CGM.VoidTy, /*isVarArg=*/false);
           StringRef PureCallName = CGM.getCXXABI().GetPureVirtualCallName();
           PureVirtualFn = CGM.CreateRuntimeFunction(Ty, PureCallName);
+          if (auto *F = dyn_cast<llvm::Function>(PureVirtualFn))
+            F->setUnnamedAddr(true);
           PureVirtualFn = llvm::ConstantExpr::getBitCast(PureVirtualFn,
                                                          CGM.Int8PtrTy);
         }
@@ -618,6 +620,8 @@ llvm::Constant *CodeGenVTables::CreateVTableInitializer(
           StringRef DeletedCallName =
             CGM.getCXXABI().GetDeletedVirtualCallName();
           DeletedVirtualFn = CGM.CreateRuntimeFunction(Ty, DeletedCallName);
+          if (auto *F = dyn_cast<llvm::Function>(DeletedVirtualFn))
+            F->setUnnamedAddr(true);
           DeletedVirtualFn = llvm::ConstantExpr::getBitCast(DeletedVirtualFn,
                                                          CGM.Int8PtrTy);
         }
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index fad31995ed5..73cf47c69ab 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -906,12 +906,6 @@ void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
     F->removeFnAttr(llvm::Attribute::InlineHint);
   }
 
-  if (isa<CXXConstructorDecl>(D) || isa<CXXDestructorDecl>(D))
-    F->setUnnamedAddr(true);
-  else if (const auto *MD = dyn_cast<CXXMethodDecl>(D))
-    if (MD->isVirtual())
-      F->setUnnamedAddr(true);
-
   unsigned alignment = D->getMaxAlignment() / Context.getCharWidth();
   if (alignment)
     F->setAlignment(alignment);
@@ -1079,6 +1073,12 @@ void CodeGenModule::SetFunctionAttributes(GlobalDecl GD, llvm::Function *F,
     F->addAttribute(llvm::AttributeSet::FunctionIndex,
                     llvm::Attribute::NoBuiltin);
 
+  if (isa<CXXConstructorDecl>(FD) || isa<CXXDestructorDecl>(FD))
+    F->setUnnamedAddr(true);
+  else if (const auto *MD = dyn_cast<CXXMethodDecl>(FD))
+    if (MD->isVirtual())
+      F->setUnnamedAddr(true);
+
   CreateFunctionBitSetEntry(FD, F);
 }