Re: [Patch] GCN: Add pre-initial support for gfx1100

[Andrew Stubbs <ams@codesourcery.com>]

On 07/01/2024 19:20, Tobias Burnus wrote:
> ROCm meanwhile supports also some consumer cards; besides the semi-new 
> gfx1030, support for gfx1100 was added more recently (in ROCm 5.7.1 for 
> "Ubuntu 22.04 only" and without parenthesis since ROCm 6.0.0).
> 
> GCC has already very limited support for gfx1030 - whose multlib support 
> is - on purpose - not yet enabled by default and is WIP.
> 
> The attached patch now adds gfx1100 on top of it, assuming that it 
> mostly behaves the same as gfx1030. This is really WIP as there are 
> known build (assembly) issues (see below) and not only "just" runtime 
> issues.
> 
> gfx1100 differs at least in the following aspects from the previously 
> supported cards:
> 
> * gfx1100 has an 'architected flat scratch' which is different from 
> 'absolute flat scratch' which all others (but fiji: 'offset flat 
> scratch') have. Hence, '.amdhsa_reserve_flat_scratch 0'
> has to be excluded to avoid assembly errors.
> 
> * gfx1100 also does not support 'v_mov_b32_sdwa', failing to assembly
>    libc/argz/libc_a-argz_stringify.o with:
>    "sdwa variant of this instruction is not supported"
> → This has not been address in the patch, hence, specifying gfx1100 in 
> --with-multilib-list= will fail to build when an in-tree newlib is build.
> 
> * * *
> 
> The attached patch fixes in addition one issue in libgomp (string-length 
> len constant is too short for gfx1030 (and gfx1100) = 7 characters) and 
> it includes the fix that __gfx1030__ is not defined, which I have 
> submitted separately (yesterday).
> 
> With the caveat that gfx1100 is even less usable than gfx1030 and it 
> won't build newlib, is it nonetheless
> 
>    OK for mainline ?
> 
> (As gfx1100 is not enabled by default in multilib, a regular build will 
> will not fail and I think the *.md issue can be addressed separately.)

This looks fine to me. I know there will be things that need fixing for 
both experimental architectures.

Andrew

P.S. Apologies, but I think my commits today conflict a little; you 
should be able to drop the hunks that patch deleted code.