[Libre-soc-isa] [Bug 933] prefix-code (like huffman code) decode/encode instructions

[bugzilla-daemon at libre-soc.org]

https://bugs.libre-soc.org/show_bug.cgi?id=933

--- Comment #18 from Jacob Lifshay <programmerjake at gmail.com> ---
(In reply to Luke Kenneth Casson Leighton from comment #15)
> (In reply to Luke Kenneth Casson Leighton from comment #14)
> 
> > +56,ALU,OP_PCDEC,RA,RB,RC,RT,NONE,CR0,0
> > +        elif regs == ['RA', 'RB', 'RC', 'RT', '', 'CR0']:  # pcdec
> 
> (CRout=CR0 is exclusively reserved for instructions that
>  have an Rc=1 form.  stbcx/stwcx perform explicit CR0
>  writing. the instruction should be *named* "pcdec." if
>  permanently writing to CR0. yes it's... awkward.)

i was following the phrase in v3.1B section 1.3.2 notation:
A period (.) as the last character of an instruction mnemonic means that the
instruction records status information in certain fields of the Condition
Register as a side effect of execution.

Somehow I got it in my head that that only meant comparing the output to zero,
like how Rc usually works.

I'll rename it.

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