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From: "linkw at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/107412] Miss to fold LEN_{LOAD,STORE} when
 the specified length equal to vector length
Date: Mon, 31 Oct 2022 06:39:47 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107412

--- Comment #3 from Kewen Lin <linkw at gcc dot gnu.org> ---
(In reply to Segher Boessenkool from comment #2)
> Make sure we only use "plain" accesses on machines that allow all unalign=
ed
> accesses?  p8 and later I think.  The load-with-length insns are even lat=
er,
> but a builtin does not necessarily translate to those newer insns, so some
> care is required :-)

Thanks for raising this, for now these LEN_{LOAD,STORE} can ONLY be generat=
ed
when the target defines the relevant optab len_{load,store}, on power it's
power9 and later, while on s390 it should be some latest cpu I guess. Those=
 are
internal function and invisible for users, the support and the documentation
assume it can work for unaligned access, if some target wants to emulate it
later, it needs some more updates (not only this folding). So we don't need=
 to
bother it for now IHMO. :)=