https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67024
Bug ID: 67024 Summary: IPA SRA removes tail-call opportunities Product: gcc Version: 6.0 Status: UNCONFIRMED Keywords: missed-optimization Severity: normal Priority: P3 Component: ipa Assignee: unassigned at gcc dot gnu.org Reporter: rguenth at gcc dot gnu.org CC: jamborm at gcc dot gnu.org Target Milestone: --- In gimple/generic-match.c the main dispatcher gimple_simplify () has tail-calls to workers that might end up not needing one of the parameters. IPA SRA removes those even though the resulting call is now more expensive than with keeping the paramters inplace. An issue might be that tail-call discovery only runs after IPA SRA.