review request (XS) - 6814552 par compact bitmap code
John.Coomes at sun.com
Wed Jun 10 23:26:45 UTC 2009
Jon Masamitsu (Jon.Masamitsu at Sun.COM) wrote:
> Looks fine.
> ... Is the switch of the multiply to
> a shift a "better safe than sorry change"? Or
> is the compiler really that bad?
Both symmetry and safety. I think using multiply for bits_to_words()
and shift for words_to_bits() would look strange. And since it could
noticeably affect performance if a compiler didn't optimize it away,
better to be safe.
> On 06/10/09 15:34, John Coomes wrote:
> > One file, very simple, use explicit shifts instead of multiply &
> > divide.
> > http://cr.openjdk.java.net/~jcoomes/6814552-shift/
> > -John
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