[PATCH 2/4] config.guess, configure.ac: Add detection of IBM z13

[Marius Hillenbrand]

On 3/9/21 12:20 PM, Torbjörn Granlund wrote:
> I applied patch 1/4 and 2/4 with modifications.
> Please take a look at the repo code when you have the time.

Thanks!

One minor proposal (patch to follow): Some versions of GCC only accept
the -march=arch<nr> variant of the most recent CPU level they support
(e.g., GCC-9 accepts -march=arch13 but not -march=z15; 13 as in the 13th
edition of the Principles of Operations that describe the ISA
extensions; both parameters are equivalent in later versions of GCC).

> The main change I made to your suggested change is that I added z14 and
> z15 to the recognised cpu types.  I also made z13 a fallback for z14 (if
> the latter is not understood by tools), and analogously made z14 and z13
> fallbacks for z15.

That absolutely makes sense. When I wrote my patches initially, it was
not yet clear that it is worthwhile to differentiate.

> I don't know how relevant the 31-bit ABI is today.  I do not plan to
> write any new asm for that, and so did not add special paths for newer
> CPUs for that ABI.

Vector extensions are only available in 64-bit / z/Architecture mode,
and I will focus on those for now.

Marius
-- 
Marius Hillenbrand
Linux on Z development
IBM Deutschland Research & Development GmbH
Vors. des Aufsichtsrats: Gregor Pillen / Geschäftsführung: Dirk Wittkopp
Sitz der Gesellschaft: Böblingen / Registergericht: Amtsgericht
Stuttgart, HRB 243294