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by magicalhippo 1386 days ago
That assumes you can do multiple divisions in parallel. Back in the good old days, a single division unit was the norm, and it still is on most microcontrollers (assuming they even have hardware floating-point division[1]).

Anyone have any references on how the current state of affairs on modern AMD/Intels?

[1]: ARM Cortex-M4 for example can have a hardware FPU, but where division and sqrt are optional, see https://developer.arm.com/documentation/102832/latest/

2 comments

https://en.wikichip.org/wiki/intel/microarchitectures/sunny_...

Looks like one FP divider on modern intel. Though you can pack multiple divisions into an instruction.

For AMD I can find throughput numbers but not how many there are, in a brief search. I'd guess two??

Interesting! Looks like my guess was off -- mea culpa.
It appears that Agner Fog's website is down at the moment, so we must conclude that the universe does not want to share this knowledge.