WebAssembly is a virtual instruction set architecture that was designed to provide an "assembly language for the web." WebAssembly has a text format designed to be readable by humans and a binary format designed to be efficiently downloaded over a network. Different runtimes interpret this virtual assembly language and generate native machine code that can be executed on native processors such an Intel or ARM. In order to guarantee that WebAssembly code can run on different machines correctly, the WebAssembly specification body has created an extension to the WebAssembly Text format *.wat called *.wast. This provides a set of assertions used to test standards compliance.
Typically, WebAssembly is interpreted or just-in-time compiled. However, or aWsm compiler takes a different approach and uses ahead-of-time compilation. This makes it challenging for us to run *.wast tests. When debugging the compiler, the tests were previously manually ported by hand. In general, the declarative assertions of the *.wast format was replaced with imperative control flow written by hand in *.wat. More information can be find in the README at https://github.com/gwsystems/aWsm/tree/master/tests/wat. In the future, the WebAssembly test suite is likely to expand and evolve, there needs to be a better way to port tests.
Write a program in Rust to automate transforming the *.wast declarative assertions into usable and readable *.c and *.wasm files
- src/main.rs
src/main.rs takes the .*wast file as input and creates *.c and *.wasm files of the same name. The *.c file contains the assert declarations. The *.wasm file contains the functions from the WebAssembly module. These declarations will run the functions that are within the *.wasm file in order to test the assertions. A *.c and *.wasm file pair is made per each module within the *.wast file.
- src/add_test.wast
src/add_test.wast is a simple WebAssembly programming that executes addition. It is used as a sample program to test the src/main.rs program.
- add_test_0.c
add_test_0.c is the resulting *.c file from running cargo run src/add_test.wast.
- add_test_0.wasm
add_test_0.wasm is the resulting *.wasm file from running cargo run src/add_test.wast.
- Installing Rust: doc.rust-lang.org
Use the command: cargo run [ path ], where the [ path ] is the relative path of the target *.wast file.