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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug tree-optimization/36188] missed optimistic value-numbering on
 global vars
Date: Mon, 30 Aug 2021 07:52:42 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D36188

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|2009-04-22 21:49:30         |2021-8-30
                 CC|                            |hubicka at gcc dot gnu.org
            Summary|missed CCP on global vars   |missed optimistic
                   |                            |value-numbering on global
                   |                            |vars

--- Comment #10 from Richard Biener <rguenth at gcc dot gnu.org> ---
IIRC we had talked about IPA discovering variables used only in a single
function so we could treat them optimistically (with the complication of
recursion representing backedges).  Eventually IPA REFs give us enough info
already
but then IPA REFs are not available to scalar (post-IPA) passes.=