[Bug ipa/122951] New: flatten_depth attribute should be added

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122951

            Bug ID: 122951
           Summary: flatten_depth attribute should be added
           Product: gcc
           Version: 16.0
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: ipa
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---

Currently GCC has a flatten attribute which is infinite flatten (LLVM
[incorrectly?] implemented it as just one level which is why GCC has a compile
time issue with it) but it would be nice to have an attribute which limits the
depth of the flatten due to compile time (especially with respect to LTO).

See
https://discourse.llvm.org/t/rfc-function-level-flatten-depth-attribute-for-depth-limited-inlining/89017/
also.