Re: [gentoo-dev] Review: desc/cpu_flags_x86.desc

[Alexis Ballier]

On Sun, 18 Jan 2015 21:44:05 +0100
Michał Górny <mgorny@g.o> wrote:

> Hello,
>
> I would like to commit the following flags as cpu_flags_x86_desc.
> The list combines global USE flags with some local USE flags I've been
> able to find.
>
>
> 3dnow - Use the 3DNow! instruction set
> 3dnowext - Use the Enhanced 3DNow! instruction set
> aes-ni - Enable support for Intel's AES instruction set (aes in
> cpuinfo) avx - Adds support for Advanced Vector Extensions
> instructions avx2 - Adds support for Advanced Vector Extensions 2
> instructions fma - Use the Fused Multiply Add instruction set
> mmx - Use the MMX instruction set
> mmxext - Use the Extended MMX instruction set (intersection of
> Enhanced 3DNow! and SSE instruction sets) (3dnowext or sse in
> cpuinfo) padlock - Use VIA padlock instructions popcnt - Enable
> popcnt instruction support sse - Use the SSE instruction set
> sse2 - Use the SSE2 instruction set
> sse3 - Use the SSE3 instruction set (pni in cpuinfo)
> sse4 - Enable SSE4 instruction support
> sse4_1 - Enable SSE4.1 instruction support
> sse4_2 - Enable SSE4.2 instruction support
> sse4a - Enable SSE4a instruction support
> ssse3 - Use the SSSE3 instruction set
>

ewwww... are you aware that these descriptions are close to useless ?
'foo - enable foo' -> thanks for the information I couldn't have
guessed...


you already have more useful ones available:

<flag name="fma3">Enables FMA3 optimizations: AMD processors starting
  with Piledriver architecture and Intel Haswell based processors or
  later.</flag>
<flag name="fma4">Enables FMA4 optimizations: AMD processors starting
with Bulldozer architecture.</flag>
<flag name="sse4_2">Enables SSE4.2 optimizations: Nehalem-based Intel
Core i7 or later.</flag>
<flag name="ssse3">Faster floating point optimization for SSSE3 capable
chips (Intel Core 2 and later chips)</flag>

and so on...


Alexis.