On Mon, Sep 7, 2020 at 7:06 AM Segher Boessenkool <seg...@kernel.crashing.org> wrote: > > On Fri, Sep 04, 2020 at 11:52:13AM -0700, H.J. Lu wrote: > > On Fri, Sep 4, 2020 at 11:09 AM Segher Boessenkool > > <seg...@kernel.crashing.org> wrote: > > > On Fri, Sep 04, 2020 at 10:34:23AM -0700, H.J. Lu wrote: > > > > > You probably have to do this for every target separately? But it is > > > > > not > > > > > enough to handle it in the epilogue, you also need to make sure it is > > > > > done on every path that returns *without* epilogue. > > > > > > > > This feature is designed for normal return with epilogue. > > > > > > Very many normal returns do *not* pass through an epilogue, but are > > > simple_return. Disabling that is *much* more expensive than that 2%. > > > > Sibcall isn't covered. What other cases don't have an epilogue? > > Shrink-wrapped stuff. Quite important for performance. Not something > you can throw away. >
Qing, can you check how it interacts with shrink-wrap? -- H.J.
