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Date: Mon, 8 Jan 2024 08:00:11 -0800
From: Christoph Hellwig <hch@infradead.org>
To: David Vernet <void@manifault.com>
Cc: Christoph Hellwig <hch@infradead.org>,
	Alexei Starovoitov <alexei.starovoitov@gmail.com>,
	Dave Thaler <dthaler1968@googlemail.com>, bpf@ietf.org,
	bpf <bpf@vger.kernel.org>, Jakub Kicinski <kuba@kernel.org>
Subject: Re: [Bpf] BPF ISA conformance groups
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On Fri, Jan 05, 2024 at 04:07:11PM -0600, David Vernet wrote:
> 
> So how do we want to move forward here? It sounds like we're leaning
> toward's Alexei's proposal of having:
> 
> - Base Integer Instruction Set, 32-bit
> - Base Integer Instruction Set, 64-bit
> - Integer Multiplication and Division
> - Atomic Instructions

As in the 64-bit integer set would be an add-on to the first one which
is the core set?  In that case that's fine with me, but the above
wording is a bit suboptimal.

> And then either having 3 separate groups for the calls, or putting all 3
> in the basic group? I'd lean towards the latter given that we're
> decoupling ISA compliance from the verifier, but don't feel strongly
> either way.

What would be the three different groups for the calls?  I think just
having the call instruction in the base group should be fine.  We'll
need to put in some wording that having support for any kind of call
depends on the program type.