Nick Fitzgerald

> I'm not aware of any current embedding of `wasmparser` where validation performance is of the utmost importance. +cc @Robbepop. You've sent PRs improving `wasmparser` performance in the past, is...

> 1. The [representation of `ValType`](https://github.com/bytecodealliance/wasm-tools/pull/701#discussion_r940519444) uses some `#[repr(packed)]` tricks to be 4-bytes but this means that you can't have more than 65k function types in a module. Currently we...

Looking at the representation of `ValType` (and `RefType` and `HeapType`) I think we could do a bit better. We need at least 20 bits to represent at least 1 million...

Alex and I just talked offline about this PR and its performance regression. We agreed that ultimately the regression is acceptable. It is pretty much a fact of life that...