[Libre-soc-isa] [Bug 1183] add /mrr mode (reverse mode) to Data-Dependent Fail-First CR_ops

[bugzilla-daemon at libre-soc.org]

https://bugs.libre-soc.org/show_bug.cgi?id=1183

--- Comment #14 from Luke Kenneth Casson Leighton <lkcl at lkcl.net> ---
(In reply to Jacob Lifshay from comment #13)
> (In reply to Luke Kenneth Casson Leighton from comment #12)
> > look again at the table. SNZ is not present.
> 
> This table:

current spec

https://git.libre-soc.org/?p=libreriscv.git;a=blob;f=openpower/sv/cr_ops.mdwn;h=d4e81fc46e32cde93ec92c0d764ee16706b4fea9;hb=a3f5eea083533cb3828f0d2a4375c49e2a7b30f1#l79

SNZ cannot be added to simple or mapreduce as it is meaningless.

> (In reply to Luke Kenneth Casson Leighton from comment #2)
> >  |6 | 7 |19:20|21 | 22:23   |  description     |
> >  |--|---|-----|---|---------|------------------|
> >  |RG|SNZ|0  0 |/  | dz  sz  | simple mode                      |
> >  |RG|SNZ|1  0 |/  | dz  sz  | scalar reduce mode (mapreduce) |
> >  |RG|SNZ|VLI 1|inv|  CR-bit | Ffirst 3-bit mode (implicit zz=1)     |
> >  |RG|SNZ|VLI 1|inv|  dz sz  | Ffirst 5-bit mode (implies CR-bit from result)|

comment #2, that's me...

ah my mistake, i am having difficulty recalling the spec, it has
been too many months since i looked at this and my knowledge is
no longer in "electrical neuron memory", you'll need to be patient,
it will take a couple of days of thinking re-reading and conversation
for everything to come back.

-- 
You are receiving this mail because:
You are on the CC list for the bug.