Javascript Helper Mode

[csjh]

Similar to #1 but more dependent on JS. The goal of it is:

• Based on the premise that the functions being called aren't the core of the program (ie no or little persistent state), and instead just a fast function/library being swapped in
  • for example, some computation or serde or something
• Only (heap-based) globals (though they aren't necessary for initial implementation) and returned objects stay on heap
  • note static sized globals are fine, ez implementation
  • everything else is arena allocated and forgotten about (or zeroed) when initial function returns
  • this would probably be done in generated wrapper javascript function
• pros:
  • fast allocation
  • fast (0 time) deallocation
  • efficient passed back structs
  • convenient, no memory management needed
• cons:
  • if allocating in a loop or something repeatedly, arena usage could grow very fast, and free'ing would be weird without a bunch more complexity
    • look into how others do it
      • is tight malloc/free even a common thing though? more probable it would happen on the stack
• things to think about:
  • how should heap memory work? only globals would access it, but if that's forbidden, then it would allow very nice(?) memory layout of [static | stack | <objects in jsland, expands forward, basic linkedlist to figure out position(?)> | empty space | arena, expands down]
    • how does arena work when memory.grow? memcpy?
  • objects in jsland optimized malloc:
    • first: (15 bit?) enumeration of all sizeof(struct)s
    • then: [16 bit free status + enumeration, sizeof(struct)]
    • malloc iterates thru based on sizeof(), looking for big enough free chunk