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Re: P4 support question (-> FAQ?)

On Thursday 24 May 2001 17:51, Will Menninger wrote:
> Hello,
> Is there a way to add a question to the gcc FAQ database on the web?
> Either way, I'd like to see this question added to the platform specific
> section (and hopefully answered):  What is the timeline (if any) for
> supporting Pentium 4 specific instructions (e.g. SSE-2) in gcc?  Is this
> being worked on or expected to occur in a specific release of gcc?
> Please refer me to the appropriate link if this question is answered
> somewhere in the gcc web pages.

My experince with gcc 2.x is that use of specific instructions brings only 
minimal sped increases in 99 % of cases, the real speed boost is given by
using sequences who are optimized for processor.  In other words -march=
(use of specific instructions) brins very little improvement over -mcpu= 
(optimized for specific cpu but using only 386 instructions).

This could change the day gcc genartes MMX instructions but for now the 
question should be when will gcc be able to optimize for PIV?


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