[Libre-soc-dev] daily kan-ban update 24nov2020

[Jacob Lifshay]

today:
Finished the 16-bit compressed instructions demo:
https://libre-soc.org/openpower/sv/16_bit_compressed/demo/
I ended up writing an assembler in bash for the demo:
https://git.libre-soc.org/?p=libreriscv.git;a=blob;f=openpower/sv/16_bit_compressed/demo_assembler.sh;hb=HEAD
I also wrote an example predecoder that works with O(log N) gate depth
that handles the full details of the proposed 16/32/48/64-bit
encoding. It outputs an array corresponding to 16-bit instruction
memory units with a flag for each 16-bit unit indicating if that
particular unit is the start of an instruction as well as the mode
that instruction should be decoded in. I'm assuming it's relatively
easy to figure it out from there. instruction decode modes are assumed
to be kinda part of the PC instead of like VLE where they are set in
the page table.

Jacob