Re: [PATCH bpf-next v3] m68k, bpf: Add initial BPF JIT compiler support
From: Kuan-Wei Chiu
Date: Mon May 18 2026 - 13:18:02 EST
Hi Andreas,
On Tue, May 12, 2026 at 07:32:44PM +0200, Andreas Schwab wrote:
> On Mai 11 2026, Kuan-Wei Chiu wrote:
>
> > +
> > + emit_16(ctx, 0x4a80 | d_lo); /* tst.l d_lo */
> > + emit_16(ctx, 0x6b04); /* bmi.s .+6 */
> > + emit_16(ctx, 0x7000 | (d_hi << 9)); /* moveq #0, d_hi */
> > + emit_16(ctx, 0x6002); /* bra.s .+4 */
> > + emit_16(ctx, 0x70ff | (d_hi << 9)); /* moveq #-1, d_hi */
>
> I think this could be "tst.l d_lo; smi d_hi; extb.l d_hi".
>
Sorry for the late reply, and thanks for the review.
This makes sense.
I initially kept things simple to focus on correctness first, but since
you pointed it out, I will include this optimization in the next
respin.
Thanks!
Regards,
Kuan-Wei