VM work

[dignifiedquire]

This is an issue to track various things that need to happen on the VM side of things.

After starting to work on #288 I realized that a few things need likely figuring out before a serious proposal makes sense, my current thinking of the ordering on things needed is:

1. Figure out encodings (This is mostly VM ABI Compatibility #288)
2. Design Init + Privileged Actors, with versioning in mind
3. Move builtin actors to be loaded using the genesis block + init actor
4. Signature validation inside the VM
5. Design VM interface in go, so we can abstract away wasm or builtin in
   go actors.
6. Figure out storage
7. Figure out metering
8. Design Cron actor
9. Definitively answer whether we are doing anything about https://docs.google.com/document/d/1UgVjJ5yInTuya9cAbO6lmqTqH-l1_rxRKAUOXfu-7pk/edit in the near term

[whyrusleeping]

It seems to me like 4 should be first. And that 5 should be at least figured out before attempting number 3. Also 7 and 8 seem more important than 6.

Work on 4 should be pretty isolated from everything else, so I would start there.

[dignifiedquire]

• Agreed on 7 and 8 being more important, moved them up
• I will try and do the encoding stuff first, it can probably be done in isolation, it'll just create some requirements on the other steps
• 5 & 3 will probably need thought on both ends at the same time

[phritz]

Is the list in the original comment ordered by priority & dependencies?

[dignifiedquire]

It is ordered in the way I was planning to tackle it, so roughly yes

[aboodman]

OK, I've spoken to all the relevant folks I believe. I'm going to start splitting this up into separate issues so that they can be prioritized separately.

[aboodman]

Note: I've added a #9 above (processing model) as it is something that has come up a lot and has equal ability to be a protocol-level change.