[OpenBIOS] Re: Dictionary Compression vs eXecute In Place

[Wookey]

+++ Stefan Reinauer [03-11-19 22:40 +0100]:
> Hi,.
> 
>    
> 2) XIP (eXecute In Place)
> 
>    If not compressing the dictionary, it could be changed so that
>    all but the readwriteable data can be executed directly from ROM.
>    This would decrease the use of RAM in embedded systems noticeably,
>    but it is also slower on about every system.
> 
>    * pro: extremely low memory usage ( < code size)
>    * con: slow execution.

It also doesn't work on systems which boot from nand flash, (increasing
numbers of arm-based devices for example). XIP is possible on NOR flash (but
pretty slow), but not NAND, in the same way that it's not possible from
Disk. This may not be terribly relevant as I'm not sure how much use
openBIOS is likely to see on such devices, but I thought I should point it
out.

Wookey
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