FPChecker and Herbie are complementary. FPChecker runs the dynamic analysis to figure what your code is actually doing under realistic workloads, which gives you the information to make those code improvements via other tools like Herbie.

Part of the issue with saying what you mean in numerical code is that approximately no-one outside a small cadre of experts bothers to do numerical analysis. And unless you're in HPC, very few of those experts are optimizing for the kind of constraints your program has. Gamedevs often care more about reproducibility and performance than characterizing accuracy or stability, for example [0].

This tool is neat because you can take whatever garbage code you're given and dynamically analyze it in-situ as a quick first step that might suffice instead of a much more difficult numerical analysis.

[0] https://jrouwe.github.io/JoltPhysics/#deterministic-simulati...

I'm someone who has worked on Herbie. AFAIK we work(ed) with the LLNL guys and they are aware of Herbie! Floating Point research is a very small world.