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From: "crazylht at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/54346] combine permutations
Date: Tue, 11 Oct 2022 06:36:01 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D54346

--- Comment #7 from Hongtao.liu <crazylht at gmail dot com> ---
(In reply to Marc Glisse from comment #6)
> The log says that this breaks tree-ssa/forwprop-19.c, but I don't see any
> xfail or anything. Does it only fail because gimple-simplify leaves some
> dead code around, so you could update the test to scan the next DCE pass
> dump instead of forwprop1? Or are we missing a transformation that just
> detects a VEC_PERM_EXPR with an identity permutation?

Uoops, I didn't notice this, will add an incremental patch to handle the
indentical index (forwporp-19.c) scenario=EF=BC=8C sorry.=