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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	[thread overview]
Message-ID: <bug-114270-4-tr7Z5kNapk@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-114270-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114270

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.

  parent reply	other threads:[~2024-03-08  8:28 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-03-07 15:31 [Bug middle-end/114270] New: " antoshkka at gmail dot com
2024-03-07 15:50 ` [Bug middle-end/114270] " pinskia at gcc dot gnu.org
2024-03-08  8:28 ` rguenth at gcc dot gnu.org [this message]
2024-03-08  9:10 ` jakub at gcc dot gnu.org

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