Add memory64 and table64 support to the Canonical ABI#624
Add memory64 and table64 support to the Canonical ABI#624adambratschikaye wants to merge 2 commits intoWebAssembly:mainfrom
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Parameterize the Canonical ABI to handle 32-bit or 64-bit memory addresses and table indices. This is done by adding two new fields to `LiftOptions` to indicate if the `memory64`/`table64` feature is being used in a core module.
alexcrichton
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alexcrichton
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Thanks so much for helping to pick this up! We chatted a bit on Zulip but for posterity I'll mention here about table-related index types how most of them want to remain 32-bits. I'll take a closer look once that's been passed over here, and in the meantime I skimmed over things and noted a few things here and there. I'm sure though that @lukewagner will have thoughts on this too!
| (param $originalSize i32) | ||
| (func (param $originalPtr $addr) | ||
| (param $originalSize $addr) | ||
| (param $alignment i32) |
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For this I might recommend making alignment have type $addr as well for consistency, and I think that matches the signature in Rust/C/etc as well.
design/mvp/Explainer.md
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| | -------------------------- | ------------------------ | | ||
| | Approximate WIT signature | `func<T>(t: T) -> T.rep` | | ||
| | Canonical ABI signature | `[t:i32] -> [i32]` | | ||
| | Canonical ABI signature | `[t:$idx] -> [i32]` | |
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This'll be a bit subtle, but this'll actually want to be a mapping of i32 as an argument (I talked with you a bit about this already, but the input here is a host-side index so always 32-bit), but the output here should be something variable. Resource "rep"s are generally pointers in linear memory so 64-bit components are going to want 64-bit storage values. In the component model resources are defined with (rep i32) and validation currently requires that i32 is the only one listed there, but this PR will relax that meaning that the resource type itself stores the lowered type which'll get plumbed here.
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Parameterize the Canonical ABI to handle 32-bit or 64-bit memory addresses and table indices. This is done by adding two new fields to
LiftOptionsto indicate if thememory64/table64feature is being used in a core module.