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Re: Re: [f-cpu] 15 MIPS FC0 emulator



Hi,

> >> For cload/cstore, I think that because nobody reply on Yann mail :
> >>  "Re: [f-cpu] Conditionnal load and store, the return" (Date :
> >> Fri, 30 Aug 2002 01:31:03 +0200), it was accepted.

> >Wrong. I know that SW people liked it, but it makes the implementation
> >too complex.

> huh i have to find exactly what it is about.
> But i think that conditional load and store is
> not a big problem. The exact semantics and behaviour
> has to be defined but basicly, cload/cstore use the
> same mechanism as conditional moves (for the condition
> part) and the usual load/store (instead that it doesn't
> trap when the condition is false, but the operation
> is aborted anyway). See the trick ? [i wish it works,
> in practice, though ;-)]

Hum, still undecided ;-)

> >> 	* New madd/msub // I think that's now they will be removed, because
> >> normal add/sub will do it (look at Antoine/Yann mail "Re: [f-cpu]
> >> pointer add & sub").

> >Another undecided point.

> as you both know, i see no point here.
> a load to register 0 with postincrement does the same.

Still undecided ?

> >> 	* New cor/cand/mux/logic // Exist in Yann ROP2 code, but are not yet
> >> written (the copy/paste is really unclear, need to be totally rewritten)

> >Simple. But we used to call them differently:

> >    short   long        new
> >    =============================
> >    <op>a   <op>.and    cand.<op>
> >    <op>o   <op>.or     cor.<op>
> >where <op> is one of: and, or, xor, andn, orn, nand, nor, xnor.  All of
> >them take a size suffix,

> why can't nobody agree ?
> i see the combine as a suffix, because it is performed
> AFTER the logic operation. Otherwise it is potentially
> misleading.

From my point of view combine is the most important information more in this 
instruction, but the point of view are possible, and I think that we can 
specify both.

> >> 	* New safeload/safestore

> >It's not clear how that can be implemented.

> are we speaking about the atomic things ?

Yes.

Cedric
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