We (Insightful) are developing a tool for you! :) It's called Insightful PerfLab - it will work for native code (CPU and/or GPU) and is designed to help things

We (Insightful) are developing a tool for you! :) It's called Insightful PerfLab - it will work for native code (CPU and/or GPU) and is designed to help things like Blender detect performance regressions in rendering (we built it to help detect performance regressions in our game engine, and then realized it would likely be generally useful to other developers).