[Bug middle-end/126883] New: inline ilogb if the argument is normal

"pinskia at gcc dot gnu.org via Gcc-bugs" <[email protected]> Sat, 15 Aug 2026 02:28:45 +0000

Newsgroups	gmane.comp.gcc.bugs
Message-ID	<[email protected]/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126883

            Bug ID: 126883
           Summary: inline ilogb if the argument is normal
           Product: gcc
           Version: 17.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---

Created attachment 65338
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=65338&action=edit
testcase

It would be a good idea to inline ilogb if we know that the input is normal.
Note I think the inling should only happen during expand.

See attachment for a testcase.

(as an asside I noticed that dom messes up things so the x in src_f32 does not
have a global range at the end of the function).