From: Emmanuel Marty <core@suntech.fr>
  To  : ggi-develop@eskimo.com
  Date: Fri, 07 Aug 1998 08:29:18 +0000

Re: ggiGetPixelFormat and proposed new DirectBuffer scheme

Marcus Sundberg wrote:

> But IIRC we have some old Amiga coders (Emmanuel? ;) here with
> experience of such things, so it shouldn't be a problem, right?

Yup, I have been following the discussion somehow and didn't comment
since it was correct :)

On 68K you can do :

ror.w #8,d0        ; Exchange bits 0-7 & 8-15
swap d0            ; Exchange hi and low 16 bits
ror.w #8,d0        ; Exchange bits 0-7 & 8-15 again

Which is pretty much identical to i486 code with bswap.

On 68020 and up, the hardware barrel-shifter (like i386 and up) will make
it so that the ror executes in one cycle or so. I can do the assembler
optimizations
on i386 and m68K, that's not a problem - and Jason can do PPC ones now I s'pose
:)

--
Emmanuel