https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101523
--- Comment #47 from Richard Biener <rguenth at gcc dot gnu.org> ---
The rtx_equal_p change gets us 50% improvement only, it's necessary to also
disable the added_{links,notes}_insn extra re-processing to get us all the
way to -O1 speed. We'd need the worklist to avoid combine regressions there
(though for the actual testcase it doesn't make a difference).
