gcc optimisation flags for Intel Atom

[Tim Prince]

On 6/26/2012 6:39 AM, Michael Zintakis wrote:
>
>>> Personally, I think using "-O2 -march=atom -msssse3 -mfpmath=sse 
>>> -fomit-frame-pointer -pipe" is decent enough. Any other opinions? I 
>>> am using gcc 4.4.5.
>> -msssse3 -> -mssse3
> Yeah, it was a typo, thanks!
>
>> As I know, -mfpmath=sse may slow some code speed in some 
>> architechures, but I don't know if it also is on ATOM.
> No idea! Hopefully, some of the more knowledgeable on this ML could 
> provide some insights.
Do you refer to the pentium-m?   Last I knew, gcc -m32 still had 
available -march=pentium-m, so you could experiment with that if you are 
interested. IIRC, there was just one decoder for SSE2, so it was 
possible to gain by mixing 387 and sse when vectorization was not 
successful.  I've never heard of much interest in comparing atom with 
pentium-m, even though each might have been a reasonable choice for 
personal laptop in its time.

-- 
Tim Prince