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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug middle-end/98429] Some FMA expressions are evaluated less
 efficiently when -ffast-math is active
Date: Tue, 05 Jan 2021 09:45:33 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D98429

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2021-01-05
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
          Component|tree-optimization           |middle-end

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
This probably asks for a special case during RTL expansion or FMA forming
phase.
In itself this is first canonicalization (the user could have written
x*(1-y) which should also expand to FMA I suppose).=