[clang] [analyzer] Model concrete floating-point values (PR #214098)

[Balázs Benics via cfe-commits]

https://github.com/steakhal commented:

I reviewed the code - and didn't have time to look at the tests. I'll continue with that later.

So far it looks pretty good! For the next round, I wanna be sure you have ran the tests with coverage and add tests to cover any branches in the core logic that was previously uncovered - (I assume there are uncovered branches / lines of code).

https://github.com/llvm/llvm-project/pull/214098