Cooperative Multithreading

[TartanLlama]

Implements WebAssembly/component-model#557

• Pass through all new builtins
• Basic implementations of new builtins
• Cancellation support
• Support for explicit threads continuing after the implicit thread has exited
• Match trap conditions with the spec (deferred)
• Insert threads into the instance table rather than holding them inside GuestTask
• Don't reuse the existing GuestCall functionality for new threads
• Testing (partially implemented, further testing deferred)
• Revert changes to the component_model_async_builtins and component_model_async_stackful features

prtest:full

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[TartanLlama]

Created issues #11910 #11909 #11908 to track deferred work

[TartanLlama]

@alexcrichton @dicej I think we're good to go. For CI to go green, we'd need to have WebAssembly/component-model#570 and WebAssembly/component-model#557 merged into the component model repo. What do we think about getting them merged soon @lukewagner ?

[alexcrichton]

You can also feel free to update this function --

wasmtime/crates/test-util/src/wast.rs

Line 404 in 710ba4b

pub fn should_fail(&self, config: &WastConfig) -> bool {

-- to avoid blocking on PRs and go ahead and land this with known-failing tests

[lukewagner]

@TartanLlama That is fantastic to hear! I merged CM/#570. Do you suppose you could post a note on CM/#557 noting that it has been implemented and you think it's good to merge?

[posborne]

Left a couple freestanding comments, but they are minor and can probably be deferred if relevant.

[TartanLlama]

@alexcrichton looks like one of the tests I added was missing a Miri ignore directive which failed the merge, I've added it