getCostCentreTree :: IO CostCentreTree
getCostCentreTree = do
  vals <- readIORef profilingData
  mconcat <$> mapM (uncurry toCostCentreTree) (Map.toList vals)
getCostCentreTree :: IO CostCentreTree
getCostCentreTree = do
  vals <- readIORef profilingData
  mconcat <$> mapM (uncurry toCostCentreTree) (Map.toList vals)
getCostCentreTree = do
  vals <- readIORef profilingData
  mconcat <$> mapM (uncurry toCostCentreTree) (Map.toList vals)