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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/107115] Wrong codegen from TBAA under stores that
 change effective type?
Date: Thu, 06 Oct 2022 15:32:26 +0000
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X-Bugzilla-Keywords: alias, wrong-code
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107115

--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
If we don't want to treat such copies as noop moves, then either we need to
change rtx_equal_p such that it will say MEMs aren't equal if the the alias
sets are different, or should tweak in the same spirit the i386.md peephole2
and set_noop_p (and perhaps some other spot).  But if we do either of that,=
 it
would be nice to get rid of the for assembly actually noop move later on
shortly before expansion or emit it as nothing, because assembler then does=
n't
care about alias sets.=