[linuxsh-dev] Re: Where does __sdivsi3_i4 come from?

[Paul M. <le...@li...>]

On Thu, Jun 12, 2003 at 05:35:23PM +0900, kaz Kojima wrote:
> The problem is the meaning of the macro __sh3__ and __SH4__. If they
> simply means CPU, you are right. But if they means ABI, the current
> -m4-nofpu does the correct thing, because the purpose of -m4-nofpu is
> to make programs having SH-3 like ABI and working on SH-4 CPU.
> It would be better to separate these two meanings.
>=20
It would also be better to more clearly define -m4-nofpu. The whole __sh3__=
 and
__SH4_NOFPU__ thing as it stands right now is one giant mess. The name itse=
lf
is utterly misleading, though is likely quite a bit cleaner than something
like using -mtune to adjust the ABI level. I definitely like the SHmedia
definitions quite a bit better.

I would also presume that SH-4 without FP should be mostly ABI compatible w=
ith
the SH-3. In which case, applications built with -m3 should presumably work=
 to
some degree. (I'm at least able to run -m2 and -m3 compiled applications).

Either way, I suppose going the -mno-implicit-fp route is probably the way =
to
go. It would be nice to get this merged with 3.3/3.4 definitely, as this sh=
ould
leave us with a working toolchain from stock gcc.

> >As a workaround for some of this stupidity, I went through and changed m=
ost of
> >the __sh3__ and __SH4__ checks to CONFIG_CPU_SH3 and CONFIG_CPU_SH4 -- s=
ince
> >obviously we can't rely on GCC to be correct.
>=20
> So, it might be not only a workaround but also the Right Thing.=20
>=20
I'll do this for the 2.4 branch as well then and see if things still work.