RhpFltRound/RhpDblRound are implemented using round/roundf. That's incorrect, since .NET default is round to even. Similar issue was recently fixed in NativeAOT-LLVM.

Unfortunately, roundeven/roundevenf methods are only available in C23 standard. They are implemented on glibc 2.25+ (current .NET requirement is 2.23) and missing on Bionic/MUSL libc. CoreCLR uses a custom implementation which can presumably be reused.