[PATCH i386]: Enable push/pop in pro/epilogue for modern CPUs

Jan Hubicka hubicka@ucw.cz
Thu Dec 13 20:40:00 GMT 2012


> > Here we speak about memcpy/memset only.  I never got around to modernize
> > strlen and friends, unfortunately...
> >
> > memcmp and friends are different beats.  They realy need some TLC...
> 
> memcpy and memset in glibc are also extremely fast.

The default strategy now is to inline only when the block is known to be small
(either constant or via profile feedback, we do not really use the info on
upper bound of size of the copied object that would be useful but not readilly
available at expansion time).

You can try the test_stringop script I attached and send me the results.  For
me libc starts to be win only for rather large blocks (i.e. >8KB)

Honza



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