Jan Hubicka <hubi...@ucw.cz> writes:
>> I had a terrible time figuring out what march value
>> i686-unknown-linux-gnu uses; only in gcc -v it's possible to see that it
>> uses pentiumpro, unlike pentium4 on Solaris/x86, which explains the
>> difference.
>
> What is the reason to use pentium4 for Solaris/x86? Is it -march setting or
> -mtune? For -mtune it is a terrible choice....
This was changed in
http://gcc.gnu.org/ml/gcc-patches/2010-03/msg01483.html
http://gcc.gnu.org/ml/gcc-patches/2010-04/msg00254.html
It's with_arch_32=pentium4 and with_tune_32=generic now.
The latest Oracle Studio compilers default to -xarch=sse2, which is
sse2 May use 386, MMX, Pentium_pro, SSE and SSE2
instructions.
The pentium4 over pentiumpro choice may well be the result of a
misunderstanding: as I said, the code in config.gcc setting with_arch*
is almost impossible to follow.
Rainer
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Rainer Orth, Center for Biotechnology, Bielefeld University
