Switch to maintained WASM instrumentation library

[Stebalien]

Switch from parity-wasm (now unmaintained paritytech/parity-wasm#334) to wasmparser (https://crates.io/crates/wasmparser) and wasm-encoder (https://crates.io/crates/wasm-encoder).

This means re-implementing our instrumentation logic, unfortunately. But I'd rather not maintain parity-wasm.

See #668, #602.

[Stebalien]

Given that this "works" right now, we can probably target M2.2 here.

[hunjixin]

you can assigned this issue to me, i would try to resolve this during isolation

[Stebalien]

Stay sane! And good luck!

[hunjixin]

@Stebalien confirm that this stack overflow check work can across multiple contracts?

	instrument_functions(&mut ctx, &mut module_info)?;       //inject calls in  function body but calldirect not check
	thunk::generate_thunks(&mut ctx, &mut module_info)?;   //inject the export function that be called by other actor 

right?

[Stebalien]

We don't track stack height across calls.

The code is written this way because it instruments the code before and after every function call (instrument_functions). However, it can't put any code before or after a call into an exported function because that call comes from outside of the module. So it instead replaces exported functions with "thunks" (small wrapper functions) that run a bit of stack accounting code before calling the actual function.

There is an inter-contract stack limit, but that's a fixed limit of 1025 calls.

[hunjixin]

@Stebalien finished a draft version, all units and bench tests have passed. but the performance will definitely be lower than the old version. because wasmpaser/encoder can't directly modify the original file.

many code basically follow, wasmparser parses the [u8] and got a section reader, make a section builder variable, read a elementsfrom the section reader, edits the element, and finally adds the elements to the builder.

[Stebalien]

because wasmpaser/encoder can't directly modify the original file.

parity-wasm doesn't do this either, right? I mean, in both cases, we:

• Take the original file, parse it into some structured representation.
• Apply a set of transforms.
• Write it back.

[Stebalien]

Implemented.