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Re: ix86_data_alignment: bad defaults?
> Yes, this is OK.
Thanks, applied.
> (to be very pedantic, we can assert that MAX_OFILE_ALIGNMENT>=256 on
> x86-64 targets, but well).
My head hurts at the thought of x86_64-aout.
> I fully agree with Richard's interpretation concerning
> BIGGEST_ALIGNMENT meaning - ie in special cases for perofrmance it
> definitly makes sense to use higher alignments than
> BIGGEST_ALIGNMENT (such as cache line or page alignments),
> BIGGEST_ALIGNMENT is what CPU require and runtime must provide when
> asked for.
Something like this, then?
Index: tm.texi
===================================================================
--- tm.texi (revision 122271)
+++ tm.texi (working copy)
@@ -1068,7 +1068,9 @@ Alignment required for a function entry
@end defmac
@defmac BIGGEST_ALIGNMENT
-Biggest alignment that any data type can require on this machine, in bits.
+Biggest alignment that any data type can require on this machine, in
+bits. Note that this is not the biggest alignment that is supported,
+just the biggest alignment that, when violated, may cause a fault.
@end defmac
@defmac MINIMUM_ATOMIC_ALIGNMENT