Re: [PATCH 5/9][v5] powerpc: implement is_instr_load_store().

From: Michael Ellerman
Date: Tue Oct 08 2013 - 21:27:48 EST


On Wed, Oct 09, 2013 at 12:03:19PM +1100, Michael Ellerman wrote:
> On Tue, 2013-10-08 at 12:31 -0700, Sukadev Bhattiprolu wrote:
> > Michael Ellerman [michael@xxxxxxxxxxxxxx] wrote:
> > | bool is_load_store(int ext_opcode)
> > | {
> > | upper = ext_opcode >> 5;
> > | lower = ext_opcode & 0x1f;
> > |
> > | /* Short circuit as many misses as we can */
> > | if (lower < 3 || lower > 23)
> > | return false;
> >
> > I see some loads/stores like these which are not covered by
> > the above check. Is it ok to ignore them ?
> >
> > lower == 29: ldepx, stdepx, eviddepx, evstddepx
> >
> > lower == 31: lwepx, lbepx, lfdepx, stfdepx,
>
> Those are the external process ID instructions, which I've never heard
> of anyone using, I think we can ignore them.
>
> > Looking through the opcode maps, I also see these for primary
> > op code 4:
> >
> > evldd, evlddx, evldwx, evldw, evldh, evldhx.
> >
> > Should we include those also ?
>
> Yes I think so. I didn't check any of the other opcodes for you.

Paul points out these are for the SPE extension, which we also don't
care about. So ignore those as well.

cheers
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