[alberth]

Doesn't -O2 still exclude any CPU features from the past ~15 years (like AVX).

If you know the architecture and oldest CPU model, we're better served with added a bunch more flags, no?

I wish I could compile my server code to target CPU released on/after a particular date like:

  -O2 -cpu-newer-than=2019

[cogman10]

It's not an -O2 thing. Rather it's a -march thing.

-O2 in gcc has vectorization flags set which will use avx if the target CPU supports it. It is less aggressive on vectorization than -O3.

[singron]

You can use x86_64-v2 or x86_64-v3. Dates are tricky since cpu features aren't included on all SKUs from all manufacturers on a certain date.

[SubjectToChange]

A CPU produced after a certain date is not guaranteed to have the every ISA extension, e.g. SVE for Arm chips. Hence things like the microarchitecure levels for x86-64.

[cogman10]

For x86 it's a pretty good guarantee.