It seems like a bit of a shame that wasm got support for exceptions but doesn't support effects which are a generalisation of the same concept.
https://wasmfx.dev/
I'm guessing this may be because exceptions exclusively require stack unwinding where as effects require full stack switching.
Just checked and out of the 3 major non-JS GC languages, Go and .NET aren't planning to support WASM GC due to non-matching semantics. There's an implementation for Java - TeaVM, which is an AOT Java compiler, that does have production grade support, but isn't aiming for full Java compatibility (not sure what this means in practical terms).
Native interop with JS objects on the JS GC heap isn't supported as well.
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azakai
Wait, what does this mean?
> We reuse WebAssembly linear memories under the covers to implement and sandbox the GC heap. A reference to a GC object is not a native pointer, it is a 32-bit index into the GC heap’s underlying linear memory [..] As far as being fast goes, it lets us use virtual-memory guard pages to elide explicit bounds checks, just like we do for linear memories
Array loads and stores still need an explicit bounds check, don't they? And struct loads and stores don't have one anyhow. Are there other bounds checks that Wasmtime is removing? I can't figure out what they mean here.
rbbydotdev
I'm personally excited for a better thread story (not web-workers) and JIT
ngrilly
Does it support interior pointers?
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shevy-java
WASM will be ready when GNU Hurd succeeds in running the desktop linux of the year. Already 10 years since WASM ... HTML, CSS and JavaScript all had a huge influence. WAS simply has not done so yet.
It seems like a bit of a shame that wasm got support for exceptions but doesn't support effects which are a generalisation of the same concept. https://wasmfx.dev/
I'm guessing this may be because exceptions exclusively require stack unwinding where as effects require full stack switching.
Seems like there is still progress on that though which gives hope https://github.com/WebAssembly/stack-switching/blob/main/pro...
Just checked and out of the 3 major non-JS GC languages, Go and .NET aren't planning to support WASM GC due to non-matching semantics. There's an implementation for Java - TeaVM, which is an AOT Java compiler, that does have production grade support, but isn't aiming for full Java compatibility (not sure what this means in practical terms).
Native interop with JS objects on the JS GC heap isn't supported as well.
Wait, what does this mean?
> We reuse WebAssembly linear memories under the covers to implement and sandbox the GC heap. A reference to a GC object is not a native pointer, it is a 32-bit index into the GC heap’s underlying linear memory [..] As far as being fast goes, it lets us use virtual-memory guard pages to elide explicit bounds checks, just like we do for linear memories
Array loads and stores still need an explicit bounds check, don't they? And struct loads and stores don't have one anyhow. Are there other bounds checks that Wasmtime is removing? I can't figure out what they mean here.
I'm personally excited for a better thread story (not web-workers) and JIT
Does it support interior pointers?
WASM will be ready when GNU Hurd succeeds in running the desktop linux of the year. Already 10 years since WASM ... HTML, CSS and JavaScript all had a huge influence. WAS simply has not done so yet.