Unless I’m misunderstanding your point, I don’t think what you want is possible, due to microcode. You give the AMD/Intel/Arm/etc platform some instructions to execute, and then they execute it in ways that are not guaranteed to stay the same, between microcode updates and between hardware revisions. The only guarantee is that the results you get should be the same as if the instructions you requested were executed in the order you requested them.
The sophisticated version is difficult, but there are a lot of things you can treat as "opaque, everything mutates this, lots of stuff depends on it" and still be able to make decent optimisations based on what you know.
