Oh, neat, nasm adds a prefix onto all local labels in assembly.
I forgot to add a dot to make my labels local and thought it was perf itself which added the function as a suffix in some older version.

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FFmpeg/dav1d's assembly isn't fully stripped, we keep local labels, which sometimes results in spam for long functions and weird perf results, since perf doesn't collect per-function stats, only per-label.

@lynne so having local labels gives you more insight into which of the different parts of the function is slow, but at the same time, makes it more difficult to see the performance of the whole function?

@wolf480pl If you're using perf. But if you're optimizing a function yourself as you're writing it, you'll have a much better overall function performance metric.
It's just fun to open up perf top on a system with plenty of debugging symbols to see what's happening.

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