[OpenBIOS] [PATCH 0/8] RFC: OFMEM cleanup/memory reduction patch
mark.cave-ayland at ilande.co.uk
Tue Apr 10 18:10:51 CEST 2012
On 10/04/12 15:30, Mark Cave-Ayland wrote:
> So by reducing s_ofmem_data, the main component is now the size of the
> Forth dictionary. Hmmm I've had an idea though - we could compress the
> dictionary, and then decompress/relocate into another set of
> OFMEM-allocated memory in a similar way so that the entire dictionary
> doesn't have to be part of the image.
> For example:
> $ ls -l obj-sparc64/openbios-sparc64.dict
> -rw-r--r-- 1 build build 181560 Apr 10 15:08
> Now we need to allocate 512K in total within the image in order to allow
> for new entries created by bootloaders etc. If we compress the image
> aswell, e.g. using gzip:
> $ ls -l obj-sparc64/openbios-sparc64.dict.gz
> -rw-r--r-- 1 build build 37933 Apr 10 15:08
> Then we can dramatically reduce the dictionary usage within the file
> too. I wonder if we could incorporate a simple decompressor based upon
> something like pdlzip (http://lzip.nongnu.org/pdlzip.html) to perform
> LZMA decompression/relocation on the dictionary early within the startup
Actually, it seems as if zlib contains a miniature inflator called puff
which seems license-friendly and designed for embedded applications:
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Mark Adler madler at alumni.caltech.edu
Does anyone see any reason why we couldn't use this code within OpenBIOS
to decompress the Forth dictionary in OFMEM-allocated memory at runtime?
I think with a little bit of extra work we could simply use gzip on the
command line in order to compress the dictionary at build time.
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