Re: [REGRESSION][PATCH V4 2/3] bpf jit: Let the x86 jit handlenegative offsets

From: Eric Dumazet
Date: Fri Mar 30 2012 - 14:58:17 EST


On Fri, 2012-03-30 at 17:24 +0200, Jan Seiffert wrote:
> Now the helper function from filter.c for negative offsets is exported,
> it can be used it in the jit to handle negative offsets.
>
> First modify the asm load helper functions to handle:
> - know positive offsets
> - know negative offsets
> - any offset
>
> then the compiler can be modified to explicitly use these helper
> when appropriate.
>
> This fixes the case of a negative X register and allows to lift
> the restriction that bpf programs with negative offsets can't
> be jited.
>
> Signed-of-by: Jan Seiffert <kaffeemonster@xxxxxxxxxxxxxx>

Nice work Jan, thanks a lot.

Signed-off-by: Eric Dumazet <eric.dumazet@xxxxxxxxx>



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