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Re: DFA for PPro, P2, P3
> In message <20020502223945.B5496@redhat.com>, Richard Henderson writes:
> > On Thu, May 02, 2002 at 08:28:48PM -0600, law@redhat.com wrote:
> > > That's one of the things that is (to me at least) extremely unclear about
> > > the PPro/P2/P3 pipeline -- ordering/dependency of uops.
> >
> > Well it's quite clear that a load-execute x86 insn (as your example
> > must have been)
> Actually my example was a shift of a register by a constant. Those
> are incorrectly marked as using p0 and p01 in the current pipeline
> description. If it was a load-execute it would have used p2 in some
> way. I didn't figure it was worth confusing folks with this tidbit
> of information :-)
You missunderstood the current description. It marks both p0 and p01
to avoid overloading of p01 unit when p0 instruction is already
issued.
The shift is realy just p0 instruction.
Honza