Re: Questions about runtime structure "store"

Hi Rui,
This is the kind of question that would be great to ask as a discussion on
the spec repo (https://github.com/WebAssembly/spec/discussions), since this
mailing list is very large and doesn't get a lot of traffic. But the short
answer is that the store is mostly just an abstraction for specification
purposes. Most implementations do not have a single concrete thing that
corresponds to the store. Each of those elements have individual
instructions (or host/embedding functions) that access it, e.g.
loads/stores for memory, global.get/set, table.get/set or indirect calls,
etc, as well as being initialized during instantiation.
-Derek


On Fri, Apr 15, 2022 at 7:33 AM Rain Wang <rainwang6188@gmail.com> wrote:

> Hi, I'm a student from ZJU, and interested in the WASM..
>
> I'm new to this area and currently working on a project which aims to
> verify the correctness of WASM Virtual Machines, to it's important to
> access the running state of a WASM program.
>
> I've read the spec and find that there's a runtime structure named `store
> <https://webassembly.github.io/spec/core/exec/runtime.html#store>`
> which represents all global state that can be manipulated by WebAssembly
> programs. It consists of the runtime representation of all instances of
> functions, tables, memories, and globals, element segments, and data
> segments that have been allocated during the life time of the abstract
> machine.
>
> But I found no relevant instructions that can access this structure. So
> does that mean `store` is just a concept which is not implemented yet?
>
> Best,
> Rui Wang
>