More work on thunks - don't assert if there's a variable with the same name as the thunk already.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@99303 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGVtable.cpp b/lib/CodeGen/CGVtable.cpp
index 6fee2a5..9204e4e 100644
--- a/lib/CodeGen/CGVtable.cpp
+++ b/lib/CodeGen/CGVtable.cpp
@@ -3669,8 +3669,40 @@
void CodeGenVTables::EmitThunk(GlobalDecl GD, const ThunkInfo &Thunk)
{
llvm::Constant *ThunkFn = CGM.GetAddrOfThunk(GD, Thunk);
+ const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
- (void)ThunkFn;
+ // Strip off a bitcast if we got one back.
+ if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(ThunkFn)) {
+ assert(CE->getOpcode() == llvm::Instruction::BitCast);
+ ThunkFn = CE->getOperand(0);
+ }
+
+ const llvm::Type *ThunkFnTy =
+ cast<llvm::GlobalValue>(ThunkFn)->getType()->getElementType();
+
+ // There's already a declaration with the same name, check if it has the same
+ // type or if we need to replace it.
+ if (ThunkFnTy != CGM.getTypes().GetFunctionTypeForVtable(MD)) {
+ llvm::GlobalValue *OldThunkFn = cast<llvm::GlobalValue>(ThunkFn);
+
+ // If the types mismatch then we have to rewrite the definition.
+ assert(OldThunkFn->isDeclaration() &&
+ "Shouldn't replace non-declaration");
+
+ // Remove the name from the old thunk function and get a new thunk.
+ OldThunkFn->setName(llvm::StringRef());
+ ThunkFn = CGM.GetAddrOfThunk(GD, Thunk);
+
+ // If needed, replace the old thunk with a bitcast.
+ if (!OldThunkFn->use_empty()) {
+ llvm::Constant *NewPtrForOldDecl =
+ llvm::ConstantExpr::getBitCast(ThunkFn, OldThunkFn->getType());
+ OldThunkFn->replaceAllUsesWith(NewPtrForOldDecl);
+ }
+
+ // Remove the old thunk.
+ OldThunkFn->eraseFromParent();
+ }
}
void CodeGenVTables::EmitThunks(GlobalDecl GD)
diff --git a/lib/CodeGen/CGVtable.h b/lib/CodeGen/CGVtable.h
index 450fa93..cc4cb87 100644
--- a/lib/CodeGen/CGVtable.h
+++ b/lib/CodeGen/CGVtable.h
@@ -341,7 +341,7 @@
// have, as well as the vtable itself if the global decl is the key function.
void EmitVTableRelatedData(GlobalDecl GD);
- /// GenerateClassData - Generate all the class data requires to be generated
+ /// GenerateClassData - Generate all the class data required to be generated
/// upon definition of a KeyFunction. This includes the vtable, the
/// rtti data structure and the VTT.
///