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Re: ix86_data_alignment: bad defaults?


DJ Delorie <dj@redhat.com> writes:

> > It is to improve performance of string functions on larger chunks of
> > data.  x86-64 specify this, for x86 it is optional.  I don't think we
> > should end up warning here - it is done only for static variables where
> > the alignment can be higher than what BIGGEST_ALIGNMENT promise.
> 
> Higher than BIGGEST_ALIGNMENT?  So, maybe we should rename it
> ALMOST_BIGGEST_ALIGNMENT?  I'm confused.

Yes, BIGGEST_ALIGNMENT is supposed to be the biggest alignment the
compiler will ever use.  So if ix86_data_alignment wants to return 256
for some variable, then it seems to me that BIGGEST_ALIGNMENT should
be 256.

Ian


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