Fizzy

Fizzy aims to be a fast integer-only WebAssembly interpreter written in C++.

Goals

I) Code quality

• Clean and modern C++17 codebase without external dependencies
• Easily embeddable (and take part of the standardisation of the "C/C++ embedding API")

II) Simplicity

• Interpreter only
• Provide no support for floating point operations (initially)
• Support only WebAssembly binary encoding as an input (no support for the text format (.wat/.wast))

III) Conformance

• Should pass the official WebAssembly test suite

IV) First class support for determistic applications (blockchain)

• Support an efficient big integer API (256-bit and perhaps 384-bit)
• Support optional runtime metering in the interpreter
• Support enforcing a call depth bound
• Further restrictions of complexity (e.g. number of locals, number of function parameters, number of labels, etc.)

Building and using

Fizzy uses CMake as a build system:

$ mkdir build && cd build
$ cmake ..
$ cmake --build .

This will build Fizzy as a library and since there is no public API (the so called embedder API in WebAssembly) yet, this is not very useful.

Building with the FIZZY_TESTING option will output a few useful utilities:

$ mkdir build && cd build
$ cmake -DFIZZY_TESTING=ON ..
$ cmake --build .

These utilities are as follows:

fizzy-bench

This can be used to run benchmarks available in the test/benchmarks directory. Read this guide for a short introduction.

fizzy-spectests

Fizzy is capable of executing the official WebAssembly tests. Follow this guide for using the tool.

fizzy-unittests

This is the unit tests suite of Fizzy.

Maintainers

• Alex Beregszaszi @axic
• Andrei Maiboroda @gumb0
• Paweł Bylica @chfast

License

Licensed under the Apache License, Version 2.0.