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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/115363] Missing loop vectorization due to
 loop bound load not being pulled out
Date: Thu, 06 Jun 2024 06:48:23 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D115363

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2024-06-06

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Invariant motion doesn't do versioning for aliasing.  But in fact once the
loop iterates array[k] can no longer alias this->size but this is difficult
to exploit (peeling the loop once would help).

I'm not sure we should start to version all those loops where the exit
condition depends on a not hoistable but invariant expression?

But maybe we can diagnose this so people can rewrite their code.=