Re: [patch] [MIPS] Implement Errata for 24K and 24KE

[Catherine Moore <clm at codesourcery dot com>]

Hi Richard,

Richard Sandiford wrote:
> Catherine Moore <clm@codesourcery.com> writes:
> > Richard Sandiford wrote:
> > > Catherine Moore <clm@codesourcery.com> writes:
> > > > I've attached a new patch.  It adds the testcases that you asked for
> > > > along with the other cleanups.  I had trouble with one section -- this
> > > > first example:
> > > >
> > > > 	.set	noreorder
> > > > 1:	eret
> > > > 	.set	reorder
> > > > 	b	1b
> > > >
> > > > insns_between is called only when the the history insn is not in a
> > > > noreorder block.
> > > Hmm, yeah.  So the current code doesn't behave as I said after all. ;(
> > > Sorry about that.  Serves me right for going on memory.
> > >
> > > I still think that what I said is what ought to happen.  I can't see
> > > any reason for the current approach to non-24k hazards, where we insert
> > > nops between A and B iff _A_ is not in a noreorder block.  Why should
> > > A and B be assymetric in that way?
> > This sounds like a good plan.  Will you let me know when you've
> > checked in your bit?
>
> OK, there were no objections, so I went ahead and applied it after
> testing on mipsisa64-elf.
>
> > > So assuming we can use the patch below, and drop the hunk above
> > > from your patch, the rest looks good.  However, the logic is
> > > overly complex: 
> > (code snipped).  I think that you meant for the check on insn2 to be
> > insn2 != NULL, otherwise this change looks okay to me as well.
>
> I think the original "insn2 == NULL" was right.  If insn2 is null,
> we need to assume the worst, and return 1.
   Yep.  I think you're right.  My part of the patch has been committed as well.

   Catherine