[llvm] [AArch64] A simple tool for generating a scheduling model draft from a SWOG (PR #131525)

[David Green via llvm-commits]

davemgreen wrote:

Nice tool. I'm impressed that it manages to parse the tables as cleanly as it does.

> It does not map instruction names in SWOG to names in LLVM.

That sounds like it might be the hard bit, at least it looks like it would require some manual effort. There has always been the question of which is better - trying to collect the data from a known good source or trying to measure it directly on real hardware. Both have advantages and disadvantages, and in the end of the day come from the same source (the SWOG's just have someone who knows what the right answer should be looking over the results after they are measured).

>From looking at https://reviews.llvm.org/D144388#4149183, and what I've seen of the difficulties in measuring some values reliably, perhaps we will end up needing a mixture of both approaches, with one checking the results of the other.

https://github.com/llvm/llvm-project/pull/131525