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From: "klaus.doldinger64 at googlemail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/66511] [avr] whole-byte shifts not optimized away for
 uint64_t
Date: Sun, 16 Apr 2023 17:27:33 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D66511

Wilhelm M <klaus.doldinger64 at googlemail dot com> changed:

           What    |Removed                     |Added
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                 CC|                            |klaus.doldinger64@googlemai
                   |                            |l.com

--- Comment #5 from Wilhelm M <klaus.doldinger64 at googlemail dot com> ---
(In reply to Roger Sayle from comment #4)
> Created attachment 54871 [details]
> proposed patch
>=20
> Proposed patch, using a peephole2 in avr-dimode.md to inline calls to
> __lshrdi3 that require only a single instruction or two (due to truncatio=
n).
> For truncations to char, this is smaller and faster, and for truncations =
to
> unsigned short this is the same size, but faster.  The drawback is that
> performing this late (in peephole2) doesn't eliminate the stack frame
> prolog/epilog.  Thoughts?

Looks good to me.
Many thanks!=