[Compiler] Support basic casting operations in VM

[SupunS]

Work towards #3742

Description

Adds basic support for type-casting in the VM.

Conversion for values based on type (e.g: Int16 to Int32, etc.) is not yet supported (left a TODO). It makes more sense to add those once the interpreter values are re-used.

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• Targeted PR against master branch
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work
• Code follows the standards mentioned here
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[github-actions]

Cadence Benchstat comparison

This branch with compared with the base branch onflow:feature/compiler commit 56c8fbd
The command for i in {1..N}; do go test ./... -run=XXX -bench=. -benchmem -shuffle=on; done was used.
Bench tests were run a total of 7 times on each branch.

Collapsed results for better readability

[turbolent]

Nice!

I guess the core functions of the implementation, like ConvertAndBox, Unbox, BoxOptional are "copies" of the one in the interpreter? Maybe we can refactor them (in a follow-up) so they only exist in one place so we can share the logic between interpreter and VM, and there is no chance their behaviour drifts in different directions?

[SupunS]

Yes. It's not possible to refactor yet, because the values are different, and also interpreter's functions rely on sema.Type and the VM's functions rely on StaticTypes. For the latter, I think the better approach is probably to refactor both to use StaticTypes. But again for that, we need to figure out a way / refactor the entitlements to also use StaticTypes.

I've added a item to our laundry-list for the next milestone, for adding those.

[SupunS]

Like discussed, I split the different variants of casts in to separate instructions: c76e75a.

Can you please have another look on the last commit? 🙏

[turbolent]

Nice! Looks great 👍

[turbolent]

Opened #3771 to also add some test cases for the compilation

[turbolent]

👌