cranelift

rust jit wasm webassembly runtime wasi cranelift sandbox wasmtime

Alex Crichton ec92f8e480 Make Wasmtime compatible with Stacked Borrows in MIRI (#6338 ) * Make Wasmtime compatible with Stacked Borrows in MIRI The fact that Wasmtime executes correctly under Tree Borrows but not Stacked Borrows is a bit suspect and given what I've since learned about the aliasing models I wanted to give it a stab to get things working with Stacked Borrows. It turns out that this wasn't all that difficult, but required two underlying changes: * First the implementation of `Instance::vmctx` is now specially crafted in an intentional way to preserve the provenance of the returned pointer. This way all `&Instance` pointers will return a `VMContext` pointer with the same provenance and acquiring the pointer won't accidentally invalidate all prior pointers. * Second the conversion from `VMContext` to `Instance` has been updated to work with provenance and such. Previously the conversion looked like `&mut VMContext -> &mut Instance`, but I think this didn't play well with MIRI because `&mut VMContext` has no provenance over any data since it's zero-sized. Instead now the conversion is from `mut VMContext` to `&mut Instance` where we know that `mut VMContext` has provenance over the entire instance allocation. This shuffled a fair bit around to handle the new closure-based API to prevent escaping pointers, but otherwise no major change other than the structure and the types in play. This commit additionally picks up a dependency on the `sptr` crate which is a crate for prototyping strict-provenance APIs in Rust. This is I believe intended to be upstreamed into Rust one day (it's in the standard library as a Nightly-only API right now) but in the meantime this is a stable alternative. * Clean up manual `unsafe impl Send` impls This commit adds a new wrapper type `SendSyncPtr<T>` which automatically impls the `Send` and `Sync` traits based on the `T` type contained. Otherwise it works similarly to `NonNull<T>`. This helps clean up a number of manual annotations of `unsafe impl {Send,Sync} for ...` throughout the runtime. * Remove pointer-to-integer casts with tables In an effort to enable MIRI's "strict provenance" mode this commit removes the integer-to-pointer casts in the runtime `Table` implementation for Wasmtime. Most of the bits were already there to track all this, so this commit plumbed around the various pointer types and with the help of the `sptr` crate preserves the provenance of all related pointers. * Remove integer-to-pointer casts in CoW management The `MemoryImageSlot` type stored a `base: usize` field mostly because I was too lazy to have a `Send`/`Sync` type as a pointer, so this commit updates it to use `SendSyncPtr<u8>` and then plumbs the pointer-ness throughout the implementation. This removes all integer-to-pointer casts and has pointers stores as actual pointers when they're at rest. * Remove pointer-to-integer casts in "raw" representations This commit changes the "raw" representation of `Func` and `ExternRef` to a `mut c_void` instead of the previous `usize`. This is done to satisfy MIRI's requirements with strict provenance, properly marking the intermediate value as a pointer rather than round-tripping through integers. Minor remaining cleanups * Switch to Stacked Borrows for MIRI on CI Additionally enable the strict-provenance features to force warnings emitted today to become errors. * Fix a typo * Replace a negative offset with `sub` * Comment the sentinel value * Use NonNull::dangling		2 years ago
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all	Make Wasmtime compatible with Stacked Borrows in MIRI (#6338)	2 years ago
misc_testsuite	Fix export translation for components. (#6108)	2 years ago
spec_testsuite@7ef86ddeed	Update the spec test suite submodule (#5970)	2 years ago
wasi_testsuite	test: add cases from `wasi-testsuite` (#6341)	2 years ago
host_segfault.rs	Run some tests in MIRI on CI (#6332)	2 years ago
rlimited-memory.rs	Run some tests in MIRI on CI (#6332)	2 years ago