This should make debugging and profiling much better, at little to no
runtime cost.
Also moves off the operator definitions to a separate header, so it
should also improve the editing experience quite a bit.
This commit is a fairly large refactor, mainly because it unified the
two different ways that existed to represent references.
Now Reference values are also a kind of value.
It also implements a printer for values/references instead of copying
the implementation everywhere.
This allows multiply different kinds of interpreters to be used by the
runtime; currently a BytecodeInterpreter and a
DebuggerBytecodeInterpreter is provided.
This should make it easier to implement multiple types of interpreters
on top of a configuration, and also give a small speed boost in not
initialising as many Stack objects.
Doing that was causing a lot of malloc/free traffic, but since there's
no need to have a stable pointer to them, we can just store them by
value.
This makes execution significantly faster :^)
As the parser now flattens out the instructions and inserts synthetic
nesting/structured instructions where needed, we can treat the whole
thing as a simple parsed bytecode stream.
This currently knows how to execute the following instructions:
- unreachable
- nop
- local.get
- local.set
- {i,f}{32,64}.const
- block
- loop
- if/else
- branch / branch_if
- i32_add
- i32_and/or/xor
- i32_ne
This also extends the 'wasm' utility to optionally execute the first
function in the module with optionally user-supplied arguments.
This adds very basic support for module instantiation/allocation, as
well as a stub for an interpreter (and executions APIs).
The 'wasm' utility is further expanded to instantiate, and attempt
executing the first non-imported function in the module.
Note that as the execution is a stub, the expected result is a zero.
Regardless, this will allow future commits to implement the JS
WebAssembly API. :^)