[Bug rtl-optimization/37948] [4.4 Regression] IRA generates slower code for -mtune=core2

["hjl dot tools at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #4 from hjl dot tools at gmail dot com  2008-10-29 13:08 -------
(In reply to comment #2)
> Subject: Re:  [4.4 Regression] IRA generates slower
>  code for -mtune=core2
> 
> hjl dot tools at gmail dot com wrote:
> > ------- Comment #1 from hjl dot tools at gmail dot com  2008-10-29 05:44 -------
> > It looks like the cost of loading/storing FP values aren't appropriate for
> > Core 2. With this patch:
> 
> Good.  Is regmove still helping (which would be the wrong thing to do,
> but gives a data point)?
> 
> Paolo
> 

For this bug, regmove has mixed impacts with updated core2_cost:

[hjl@gnu-6 regmove]$ ../xgcc -B../ -m32 -O2 /tmp/foo.c -o core2.sse
-mtune=core2  -msse3 -mfpmath=sse
[hjl@gnu-6 regmove]$ ../xgcc -B../ -m32 -O2 /tmp/foo.c -o o2.sse   -msse3
-mfpmath=sse
[hjl@gnu-6 regmove]$ ../xgcc -B../ -m32 -O2 /tmp/foo.c -o core2 -mtune=core2   
[hjl@gnu-6 regmove]$ ../xgcc -B../ -m32 -O2 /tmp/foo.c -o o2
[hjl@gnu-6 regmove]$ time ./o2

real    0m7.995s
user    0m7.956s
sys     0m0.003s
[hjl@gnu-6 regmove]$ time ./core2

real    0m7.951s
user    0m7.950s
sys     0m0.000s
[hjl@gnu-6 regmove]$ time ./core2.sse

real    0m7.358s
user    0m7.357s
sys     0m0.000s
[hjl@gnu-6 regmove]$ time ./o2.sse

real    0m7.177s
user    0m7.176s
sys     0m0.000s
[hjl@gnu-6 regmove]$


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37948