bearophile wrote:
Don:
Which means that memcpy probably isn't anywhere near optimal, either.<
Time ago I have read an article written by AMD that shows that indeed with
modern CPUs there are ways to go much faster, using vector asm instructions,
loop unrolling and explicit cache prefetching (but it's useful with longer
arrays only. Profile-driven optimization can tell you if a particular copy
usually copies lot of data, and use such kind of copy, that is
overkill/slow/too much code for the cache for smaller copies. As an alternative
the programmer may add some annotation to choose what copy strategy to use, but
this is not nice).
Bye,
bearophile
You could probably get good results by seeing how long the array is, though.
