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From: "acoplan at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/114674] [aarch64] ldp_fusion fails to merge 2
 strs due to imprecise alignment info
Date: Wed, 10 Apr 2024 13:27:04 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114674

Alex Coplan <acoplan at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2024-04-10

--- Comment #3 from Alex Coplan <acoplan at gcc dot gnu.org> ---
Confirmed.

I think it might be best to take the maximum MEM_ALIGN between the adjusted=
 mem
(new_mem) and the original mem (change_mem).  In this case it happens that =
the
original mem (change_mem) has a stronger alignment guarantee, but in genera=
l it
could be the case that the adjusted mem gives a better alignment guarantee.=
=20
Since both locations are known to point to the same address, it seems best =
to
me to take the largest alignment of the two.=