Re: port-powerpc/39257: Mistake in sys/arch/powerpc/powerpc/trap_subr.S file

[Konrad Karpowicz <konradk%pacomp.pl@localhost>]

Havard Eidnes pisze:
> > Tim Rightnour pisze:
> >     
> > >  I looked at the file at the location you mentioned, but I don't
> > >  think the current code in CVS matches whatever you are looking
> > >  at.  The line numbers you gave don't match up.  Can you please
> > >  either tell me what the CVS revision number at the top of the
> > >  file you are looking at is, or look at the most current one,
> > >  which is
> > >       
> > Dear Tim,
> > Thank you very much for quick answer. You are right, I was looking at 
> > trap_subr.S v1.59.
> > In v 1.64 the line numbers are 540-547.
> > Lines 540 and 541: in my opinion the contents of R1 are not used anymore.
> > Line 544: change of the contents of R2 results in incorrect value loaded 
> > into R1 in line 547.
> >     
>
> It would probably be helpful if you quoted the actual code and gave
> a bit more context, such as which function you are talking about.
> The reason I say this is that in revision 1.64 of trap_subr.S, lines
> 540-547 look as follows:
>
> #endif
> _C_LABEL(tlbdlmsize) = .-_C_LABEL(tlbdlmiss)
>
> /* LINTSTUB: Var: int tlbdsmiss[1], tlbdsmsize[1]; */
>         .globl  _C_LABEL(tlbdsmiss),_C_LABEL(tlbdsmsize)
> _C_LABEL(tlbdsmiss):
>         mfspr   %r2,SPR_HASH1           /* get first pointer */
>         li      %r1,%r8
>
> which is probably not what you wanted to indicate.
>
> Regards,
>
> - Havard
Dear Havard,

Sorry again. German NetBSD FTP server has out of date NetBSD-current.
The lines are 590-597:

   mfspr    %r3,SPR_DMISS        /* get the miss address */
   mfsrin    %r1,%r3            /* get the segment register */
   mfsrr1    %r3
   rlwinm    %r3,%r3,18,31,31    /* get PR-bit */
   rlwnm.    %r2,%r2,%r3,1,1        /* get the key */
   bne-    9b            /* protection violation */
8:    /* found, set reference/change bits */
   ldreg    %r1,4(%r2)        /* reload tlb entry */

At the moment I know which line has a bug. It is line
rlwnm.    %r2,%r2,%r3,1,1        /* get the key */
and it should be:
rlwnm.    %r1,%r1,%r3,1,1        /* get the key */

Now it seems to work OK. How is it possible that you haven't noticed it 
before?

Kind regards,
Konrad Karpowicz
PACOMP