Missing AVX2 CPU flag on OS X about py-cpuinfo

[workhorsy]

It might.

In most places it just wraps the OS tool for getting the cpu flags. So it does not look for specific cpu flags, but passes on the list that it receives. Each tool names cpu flags differently. In the case of querying the CPUID register directly with:

from cpuinfo import cpuinfo
cpuinfo.get_cpu_info_from_cpuid()

It should check for the AVX2 flag. I would recommend trying a few of the different functions and seeing the results.

[workhorsy]

Hmmm. Upon closer inspection, it seems that the get_cpu_info_from_cpuid() function is not checking for AVX2. I'll have to look at this later. It has been a long time since I wrote this assembly code.

I think this whole section is missing:
https://en.wikipedia.org/wiki/CPUID#EAX.3D7.2C_ECX.3D0:_Extended_Features

[alimanfoo]

Thanks a lot. I have a Python package which includes some C extensions, and
I need to detect AVX2 in order to decide which extensions to build.
Detection needs to work on Linux or Windows. If I can do this without cpuid
then that would be fine, although I guess using cpuid is the most direct
way to check.

On Friday, 15 January 2016, Matthew Brennan Jones [email protected]
wrote:

Hmmm. Upon closer inspection, it seems that the get_cpu_info_from_cpuid()
function is not checking for AVX2. I'll have to look at this later. It has
been a long time since I wrote this assembly code.

I think this whole section is missing:
https://en.wikipedia.org/wiki/CPUID#EAX.3D7.2C_ECX.3D0:_Extended_Features

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Alistair Miles
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Web: http://purl.org/net/aliman
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[fnino]

Ran into the same issue; it is quite easy to solve in MacOS. You should merge info from
sysctl's machdep.cpu.features and machdep.cpu.leaf7_features

[workhorsy]

I'm pretty sure this was incidentally fixed on another bug fix. Can anyone confirm that this works for them?

[fnino]

Yes, bug was fixed. Works fine in macos 10.12.4

[fnino]

great job, thanks !

[workhorsy]

This should be working now. Re-open if you have any problems.