Re: Obsolete powerpc*-*-*spe*

[Sandra Loosemore <sandra@codesourcery.com>]

On 03/15/2017 08:26 AM, Segher Boessenkool wrote:

> Since SPE and VLE only share the part of the rs6000 port that doesn't
> change at all (except for a bug fix once or twice a year), and everything
> else needs special cases all over the place, it seems to me it would be
> best for everyone if we split the rs6000 port in two, one for SPE and VLE
> and one for the rest.  Both ports could then be very significantly
> simplified.
>
> I am assuming SPE and VLE do not support AltiVec or 64-bit PowerPC,
> please correct me if that is incorrect.  Also, is "normal" floating
> point supported at all?
>
> Do you (AdaCore and Mentor) think splitting the port is a good idea?

I can't speak on behalf of Mentor, and Andrew is the target expert here, 
but we currently do ship all of SPE, VLE, and AltiVec multilibs in the 
same powerpc-eabi toolchain.  Specifically, the list is

default (603e, e300c3, G2, etc)
-te500v1
-te500v2
-te500mc
-te600
-te200z0
-te200z3
-te200z4

plus some soft-float variants, etc.  Splitting these up into multiple 
toolchains that have to be statically configured for a particular 
architecture wouldn't be zero-cost either for us, other groups in Mentor 
that repackage our toolchains, or our end users.

I'm wondering whether the code in the rs6000 backend could be refactored 
to better abstract and separate the complicated processor-dependent bits?

-Sandra