This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [PATCH][libgcc-math] Vectorized intrinsics for x86_64


On Mon, Apr 10, 2006 at 11:58:26AM -0700, Mark Mitchell wrote:
> 
> If Intel later proposes a patch that improves the code for Intel
> processors, then it will be fine too, unless it negatively impacts AMD
> chips.  If there's no way to get optimal performance on both chips with
> a single codebase, then the policy ought to be to use the same policy
> that we would use to control -mtune=generic: the default code ought to
> work as well as possible on the most popular chips, independent of
> vendor.  And, if the compiler has been configured with --with-tune=<some

Our initial analysis indicates that the current patch won't perform
well on Intel chips and any tuning for Intel chips will very likely
have negative impatch on Opteron. So the question becomes, does the
current scheme support the future changes for -mtune=generic? Are
we going to provide multiple libraries, which will be selected by
-mtune=xxx?


H.J.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]