https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118295
Bug ID: 118295
Summary: The optimization report says sqrt is not inlinable,
even when it does get inlined
Product: gcc
Version: 15.0
URL: https://godbolt.org/z/nrqjdhd5E
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: other
Assignee: unassigned at gcc dot gnu.org
Reporter: tiborgyri at gmail dot com
Target Milestone: ---
See: https://godbolt.org/z/nrqjdhd5E
Some inliner pass always reports sqrt as non-inlinable, even when it does get
inlined, eg. on modern x86 with -ffast-math the call to the library function is
reduced to a single vsqrtsd isn.
My gut feeling is that the inliner pass runs much earlier and it would be
difficult/hacky to try and teach such things to it. So I would suggest changing
its message to begin with something like "not inlinable by inlining pass",
instead of the unqualified "not inlinable", and at the same time adding an
"optimization passed" opt-report message to whichever pass inlines sqrt with
-fast-math.
This way the final opt-report would contain both the initial inlining failure,
and then the inlining success, which would make reading these reports congruent
with the code being emitted.
