Re: SH patches for 5.12

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Arnd Bergmann <arnd@arndb.de>
Cc: Rich Felker <dalias@libc.org>,
	John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>,
	Linux-sh list <linux-sh@vger.kernel.org>,
	Rob Landley <rob@landley.net>
Subject: Re: SH patches for 5.12
Date: Tue, 2 Mar 2021 15:33:58 +0100	[thread overview]
Message-ID: <CAMuHMdU4t1Dek6me6crjFYqnNUUTwOwrXxwScPLc6mB35XxGbg@mail.gmail.com> (raw)
In-Reply-To: <CAK8P3a1oCxj411vPQ9HiZpXBRQt3evP0o9RiFv6DPd9Ru2UHWQ@mail.gmail.com>

Hi Arnd,

On Tue, Mar 2, 2021 at 3:27 PM Arnd Bergmann <arnd@arndb.de> wrote:
> On Tue, Mar 2, 2021 at 3:17 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
> > On Tue, Mar 2, 2021 at 3:03 PM Rich Felker <dalias@libc.org> wrote:
> > > On Tue, Mar 02, 2021 at 09:51:23AM +0100, John Paul Adrian Glaubitz wrote:
> > > > On 2/23/21 1:56 AM, Rich Felker wrote:
> > > > > Thanks! The last one seems to be upstream already and the rest LGTM.
> > > > > I've applied them and will do some smoke checks now and then prepare
> > > > > for -next.
> > > >
> > > > Any timeline for when the PR is sent to Linus?
> > >
> > > They're in next but I got a warning from the bot on one (7ec713058f21)
> > > and haven't checked it in detail yet. In case you have a quick idea:
> > >
> > > [linux-next:master 11837/12788] arch/sh/boot/compressed/../../lib/ashldi3.c:6:11: warning: no previous prototype for '__ashldi3'
> > >
> > > Maybe it's just a duplicate of a warning that was already there and
> > > that should be dealt with too.
> >
> > I think that can be ignored safely: similar functions like __ashrdi3()
> > also lack forward declarations on SH.
> >
> > Looks like only microblaze and powerpc do have forward declarations
> > for the gcc helpers:
> > arch/microblaze/lib/libgcc.h
> > arch/powerpc/include/asm/asm-prototypes.h
> >
> > One day we may move them to asm-generic, and start using them
> > everywhere...
>
> I thought these were fundamentally architecture specific. Is it even
> possible to declare them properly?

AFAIK their asm implementation, and if the compiler generates calls
to them, is architecture-specific.  The C versions are identical.

In fact we do have shared C implementations in lib/.
And at least __ashldi3() and __ashrdi3() are identical for SH and lib/,
so the latter should be used.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds