Not all ARM systems are created equally. For example many of the 32bit ARM processor didn’t even support floating point ops. So they’d have to be calculated in software.

Aside from various different variations of ARM, I’ve worked several variations of x86 and AMD64, SPARC, PowerPC, MIPS and others I’ve likely forgotten. Not to mention a few 8-bit CPUs too, but those there more than 20 years ago and not really fair to discuss here.

in just the past ten years i’ve had to write asm for x86, arm, mips, riscv, 8051 and something else i can’t even remember. generalizing rules