At least in V8, wasm is handled by the same internals as javascript is. Its processed by the same optimization passes and turned into machine code by the same backend which generates the machine code for js.
While I'm not sure how much cross-language optimization is being done, it sounds like these all reduce to the same concepts in the end and I don't think the performance impact will be as large as you think.
While I'm not sure how much cross-language optimization is being done, it sounds like these all reduce to the same concepts in the end and I don't think the performance impact will be as large as you think.