Re: [f-cpu] Re: Floating-Point?

[Ben Franchuk <bfranchuk@jetnet.ab.ca>]

Yann Guidon wrote:
 <snip> 
> in fact, we provided another system for handling "wide" registers.
> There are usually 3 bits used by every operation code,
> one is the "SIMD" bit and the 2 others are size bits.
> In 64-bit implementations, these 2 bits are "hardwired"
> to sizes
>         00 - 8 bits
>         01 - 16 bits
>         10 - 32 bits
>         11 - 64 bits
> in "wide" implementations, a set of SRs define the mapping.
> when a task is initialised, it is set to the defaults (see above)
> to provide compatibility, then the application modifies
> the mapping. It is not hardwired but there is a user-configurable LUT.
> 
> This way, ANY arbitrary register size can be encoded.
>

Anybody for 56 bit floating point, ints, pointers ?
I was thinking LISP and other list processing languages might want to
use the upper byte for internal flags and garbage collection
and the remaining 56 bits as data in a 64 bit word. Ben.

-- 
Standard Disclaimer : 97% speculation 2% bad grammar 1% facts.
"Pre-historic Cpu's" http://www.jetnet.ab.ca/users/bfranchuk
Now with schematics.
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