urwasm TODO

urwasm-todo.md

Interpreter in Hoon

• Change memory model: random access via (map page-number=@ page-array=@)
• Revisit the model of block/loop/if and call/call_indirect execution: it appears that the current model causes unnecessary copies of the entire membuffer, slowing down the computation. So instead of cloning the core, interpreting an expression and back-propagating changes in the global state, I need to call an evaluating arm that will edit the global state in-place
• Cache function fetching:
  • Have a gate fetch-operation within apply-instruction that takes term of an instruction as an argument and returns a number of operands to be consumed and a gate to be applied to the immediate arguments and consumed operands
  • Cache that gate
  • Fetching gate and operation gates must be defined outside of hwasm core
  • Use four letters for operators (shoudld speed things up since 4 letter term is a direct atom)
• Floating point: verify roundings and such (iirc they are different in Wasm spec and default settings of ++rs and ++rd cores)
  • is it enough to change the settings?
• add missing sections (import is the most important one)
  • add some gate examples with import section (printf, Nock evaluation)
    • Nock and Hoon evaluation would probably be enough for static stuff (printf with ~& directly)
    • choose subject for Hoon evaluation when calling a function or instantiating a module (a sort of permissioning)
  • add some thread examples with import section (scry, pass a card, set a timer)
    • add permissioning in a form of a filter for cards returned by Wasm module
  • (Rust) make a crate with functions that can be imported from urwasm
• actually compute expressions for globals' values/data offsets
• Rewrite the parser: length check, functional parsing (almost) everywhere
• Add validation, move parsing and validation to wasm mark file to parse and validate at commit
• Rewrite the interpreter: remove typechecks since they are redundant after the validation

Jetting

• how wasm3 represents parsed module? when does it convert wasm instructions to its own bytecode? can I change parsed representation with the one in Hoon? (important for suspending the computation)
• Softfloat in wasm3
• Remove validation flag in the jet, add debug mode where traces are printed on crash from failed validation (to find the source of the discrepancy)