Files

Andrew Brown c3f8415ac7 fuzz: improve the spec interpreter (#4881 )

* fuzz: improve the API of the `wasm-spec-interpreter` crate

This change addresses key parts of #4852 by improving the bindings to
the OCaml spec interpreter. The new API allows users to `instantiate` a
module, `interpret` named functions on that instance, and `export`
globals and memories from that instance. This currently leaves the
existing implementation ("instantiate and interpret the first function in
a module") present under a new name: `interpret_legacy`.

* fuzz: adapt the differential spec engine to the new API

This removes the legacy uses in the differential spec engine, replacing
them with the new `instantiate`-`interpret`-`export` API from the
`wasm-spec-interpreter` crate.

* fix: make instance access thread-safe

This changes the OCaml-side definition of the instance so that each
instance carries round a reference to a "global store" that's specific
to that instantiation. Because everything is updated by reference there
should be no visible behavioural change on the Rust side, apart from
everything suddenly being thread-safe (modulo the fact that access to
the OCaml runtime still needs to be locked). This fix will need to be
generalised slightly in future if we want to allow multiple modules to
be instantiated in the same store.

Co-authored-by: conrad-watt <cnrdwtt@gmail.com>
Co-authored-by: Alex Crichton <alex@alexcrichton.com>

2022-09-12 14:23:03 -07:00

ocaml

fuzz: improve the spec interpreter (#4881 )

2022-09-12 14:23:03 -07:00

src

fuzz: improve the spec interpreter (#4881 )

2022-09-12 14:23:03 -07:00

tests

fuzz: improve the spec interpreter (#4881 )

2022-09-12 14:23:03 -07:00

build.rs

fuzz: improve the spec interpreter (#4881 )

2022-09-12 14:23:03 -07:00

Cargo.toml

Add *.wast support for invoking components (#4526 )

2022-07-27 21:02:16 +00:00

README.md

fuzz: improve wasm-spec-interpreter documentation, add library path (#4007 )

2022-04-11 09:07:58 -05:00

README.md

wasm-spec-interpreter

This project shows how to use ocaml-interop to call into the Wasm spec interpreter. There are several steps to making this work:

building the OCaml Wasm spec interpreter as a static library
building a Rust-to-OCaml FFI bridge using ocaml-interop and a custom OCaml wrapper
linking both things into a Rust crate

Dependencies

This crate only builds in an environment with:

make (the Wasm spec interpreter uses a Makefile)
ocamlopt, ocamlbuild (available with, e.g., dnf install ocaml)
Linux tools (e.g. ar); currently it is easiest to build the static libraries in a single environment but this could be fixed in the future (TODO)
libgmp, for the OCaml zarith package
git is used by build.rs to retrieve the repository containing the Wasm spec interpreter; it is safe to completely remove ocaml/spec to get a new copy

Build

cargo build --features build-libinterpret

Use FFI_LIB_DIR=path/to/lib/... to specify a different location for the static library (this is mainly for debugging). If the build-libinterpret feature is not provided, this crate will build successfully but fail at runtime.

Test

cargo test --features build-libinterpret