Re: Support for the pseudo-C BPF assembler syntax in GAS

["Jose E. Marchesi" <jose.marchesi@oracle.com>]

Odd.  I replied to this yesterday, but somehow it wasn't sent.

> On Wed, Apr 26, 2023 at 12:35 PM Jose E. Marchesi
> <jose.marchesi@oracle.com> wrote:
>>
>>
>> > On 4/26/23 10:37 AM, Jose E. Marchesi wrote:
>> >> Just a heads up, we just committed support for the assembly syntax
>> >> used
>> >> by clang to the GNU assembler [1].
>> >
>> > Thanks! Do you which gcc release is expected to contain these changes?
>>
>> This is the assembler, i.e. binutils.
>> We don't need to update the compiler.
>>
>> >> Salud!
>> >> [1] https://sourceware.org/pipermail/binutils/2023-April/127222.html
>
> This is awesome!
> We recently converted tens of thousands of lines of bpf asm from macros
> to inline asm in C.
> See tools/testing/selftests/bpf/progs/verifier_*.c
> I wonder how gas-bpf can deal with that.

Inline assembly shall work.

> We had to fix several inline asm issues in clang to get to this point
> and probably more to come.

We will give these tests a try and fix problems as we find them :)

We actually came with some ambiguities, undefined stuff, and other
issues with the syntax while doing the implementation.  We hope to
discuss some of that during the LSF/MM/BPF next week, so we can
consolidate the language in both toolchains.

Speaking of which, we are preparing the material for the "compiled BPF"
activity during LSF/MM/BPF.  I think the BPF track hasn't been scheduled
yet, but how much time will we have to discuss about the topic?