[Wasm RyuJIT] Interpreter Integration

[kg]

Code generated by Wasm RyuJIT needs to cleanly integrate with the interpreter, so that we can have a mix of interpreted and Wasm code on the stack and properly dispatch exceptions across interpreted/Wasm boundaries and perform transitions efficiently.

This has implications for our ABI, how we handle exceptions, and how we track the shadow stack.

Requirements

• Unwinding and running filters for EH should work correctly even if the stack has a mix of Wasm and interpreted managed code.
• Transitions into the interpreter should not require a unique function pointer per managed target.

(incomplete - work in progress)