[patch][rfa]: Decoding (not-so) ambiguous insns in sid/sim

[Frank Ch. Eigler]

Hi -

brolley wrote:
> [...]
> >By the way, have you tried the "funny function" above?  It would have
> >the property of separating the 0/0 and 0/N cases [...]
> >
> Yes, I considered the "funny function" but rejected it because it 
> assigns a non-zero value in the case where a given bit must always be 1 
> or always 0, e.g. p0==num_insns,p1==0. Such a bit is useless for 
> decoding purposes and is correctly assigned a value of zero both by the 
> old function and by my new function.

You mean that there are actually four separate cases to consider?

p0=X, p1=Y, num_insns=N

	X=0 / Y=0	==> result = 0
	X<N / Y=0	==> 0 < result < N
	X=N / Y=0	==> result = 0
	X!=0 / Y!=0	==> result >= N

Okay.  Tricky.

> Can I consider your response to be approval to commit?

Sure.

> What about "filter-harmlessly-ambiguous-insns"? 
> Should I remove it from insn.scm?

No opinion.


- FChE
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 232 bytes
Desc: not available
URL: <http://sourceware.org/pipermail/cgen/attachments/20020103/ba79331b/attachment.sig>