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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/114270] Integer multiplication on floating point
 constant with conversion back to integer is not optimized
Date: Fri, 08 Mar 2024 08:28:12 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114270

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2024-03-08
     Ever confirmed|0                           |1

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
I think it makes sense to optimize for 1/power-of-two only.  Whether
an actual integer division instruction we could replace x * FP_CST with
would be faster than int->FP, FP multiply, FP->int is questionable.
But a shift very likely is.

Special-casing just * 0.5 might also an option.=