lookupVar (AST.Global name) = do
  let name' = Name $ T.unpack name
  result <- findGlobal name'
  case result of
    Just value -> pure $ Just (ConstantOperand . C.GlobalReference (typeOf value) $ name')
    Nothing -> pure Nothing
lookupVar (AST.Global name) = do
  let name' = Name $ T.unpack name
  result <- findGlobal name'
  case result of
    Just value -> pure $ Just (ConstantOperand . C.GlobalReference (typeOf value) $ name')
    Nothing -> pure Nothing
lookupVar (AST.Global name) = do
  let name' = Name $ T.unpack name
  result <- findGlobal name'
  case result of
    Just value -> pure $ Just (ConstantOperand . C.GlobalReference (typeOf value) $ name')
    Nothing -> pure Nothing