update to wasmtime 3.0.0

[JakeChampion]

wasmtime 0.38.0 removed it's module linking implementation to make room for the upcoming support for the component model. bytecodealliance/wasmtime#3958

This PR removes all the module linking functionality from wizer and updates to wasmtime 0.38.0

This PR also changes from using Trap::new to using the anyhow! macro, Trap::new was removed in wasmtime 3.0.0 bytecodealliance/wasmtime#5149

I've not worked much (if at all) in the wasmtime or wizer codebases, I may have done many things which are not correct here, hopefully it's along the right tracks 🤞

[fitzgen]

LGTM, thanks! Just one test that was deleted that shouldn't be.

[fitzgen]

This test shouldn't be deleted, we should still support multi-memory Wasm.

[JakeChampion]

I've re-added it now, the test fails but I unfortunately don't know how to make it pass.

failures:

---- multi_memory stdout ----
Error: unknown operator or unexpected token
     --> <anon>:8:16
      |
    8 |     i32.store (memory $m1) offset=1337
      |                ^


failures:
    multi_memory

[fitzgen]

It looks like the WAT syntax for multi-memory has changed so that should just be

i32.store $m1 offset=1337

now.

[JakeChampion]

Thanks, I made that change to both the store calls and both the load calls however I believe it fails to generate valid wasm. The error that is generated is

Error: unknown memory 1337 (at offset 75)

This error comes from store call for the $m2 memory.

If I change the calls to use different offsets from each other then the test passes but I'm not sure if that is just avoiding a potential bug that I've introduced within this PR by updating wasmtime.

If useful, this is the wat which fails to validate:

(module
  (memory $m1 1)
  (memory $m2 1)
  (func (export "wizer.initialize")
    i32.const 0
    i32.const 41
    i32.store $m1 offset=1337
    i32.const 0
    i32.const 1
    i32.store $m2 offset=1337)
  (func (export "run") (result i32)
    i32.const 0
    i32.load $m1 offset=1337
    i32.const 0
    i32.load $m2 offset=1337
    i32.add))

And this is the wat which passes the test:

(module
  (memory $m1 1)
  (memory $m2 1)
  (func (export "wizer.initialize")
    i32.const 0
    i32.const 41
    i32.store $m1 offset=1337
    i32.const 0
    i32.const 1
    i32.store $m2 offset=1)
  (func (export "run") (result i32)
    i32.const 0
    i32.load $m1 offset=1337
    i32.const 0
    i32.load $m2 offset=1
    i32.add))

[fitzgen]

Huh. That looks correct by my reading of the parsing code but it looks like it is trying to treat the offset (static index into the memory) as a memory index (thing that decides which memory we are accessing).

[fitzgen]

Actually IDs should work too.

In fact, if I copy/paste the failing example and run our validator on it, it succeeds:

$ cat ~/scratch/multi-memory.wat 
(module
 (memory $m1 1)
 (memory $m2 1)
 (func (export "wizer.initialize")
       i32.const 0
       i32.const 41
       i32.store $m1 offset=1337
       i32.const 0
       i32.const 1
       i32.store $m2 offset=1337)
 (func (export "run") (result i32)
       i32.const 0
       i32.load $m1 offset=1337
       i32.const 0
       i32.load $m2 offset=1337
       i32.add))
$ wasm-tools validate --features multi-memory ~/scratch/multi-memory.wat 
$ echo $?
0

[fitzgen]

Are you sure that you tested that exact version of the WAT and not accidentally some in between version while editing and poking at the test case?

[JakeChampion]

I tested that exact version, yep, I've pushed it to GH now, here is the failing CI logs -- https://github.com/bytecodealliance/wizer/actions/runs/3876213375/jobs/6609775823

To get more information from that failing test, I ran this locally:
❯ RUST_LOG=debug cargo test --package wizer --test tests -- multi_memory --exact --nocapture
Which then output the message:

Error: unknown memory 1337 (at offset 75)

I'm not sure why it is failing though

[fitzgen]

Hmm maybe wasm-tools have changed since wasmtime 3.0 and 4.0? If you rebase your 4.0 work on the latest version of this branch, do you get the same failure?

[JakeChampion]

I rebased on wasmtime 4 branch and the same test failure happens.

I went to see what the prewizened wasm looked like after parsing the wat 56bb567 (#65) , and this is what it is:

 === PreWizened Wasm ==========================================================
    (module
      (type (;0;) (func))
      (type (;1;) (func (result i32)))
      (func (;0;) (type 0)
        i32.const 0
        i32.const 41
        i32.store offset=1337
        i32.const 0
        i32.const 1
        i32.store (memory 1337) offset=1)
      (func (;1;) (type 1) (result i32)
        i32.const 0
        i32.load offset=1337
        i32.const 0
        i32.load (memory 1337) offset=1
        i32.add)
      (memory $m1 1)
      (memory $m2 1)
      (export "wizer.initialize" (func 0))
      (export "run" (func 1)))
    ===========================================================================

[alexcrichton]

I've sent #75 which is a PR to this PR which I think should get the tests working.