Building standard.wat could use wasm-opt

[Acaccia]

Currently, standard.wat has a lot of functions (even basic ones) that calls subfunctions in their execution.

For example,

• add-int and add-uint call the generic add-int128.
• mul-int calls mul-uint, which calls mul-int128.
• sha256-buffer calls multiple functions to keep it simple and clean.
• ...

Problem is that those calls add up, and could become expensive. A simple solution here would be to run wasm-opt -O4 after the compilation from wat to wasm.

wasm-opt is a tool from binaryen, which is a part of the official Webassembly organization.

wasm-opt exists as a CLI tool, but exists also as a crate here: wasm-opt. This crate is (at the time of writing) two versions below the official tool.

[cylewitruk]

As long as we can run our test suite against the optimized version and ensure that nothing "broke" in the process then I think that sounds like a good idea, assuming it doesn't affect size negatively too much (since the current theory is compiling the stdlib into each individual Clarity contract).

[Acaccia]

I tried to add a wasm-opt pass in the generated code in #223, and it has issues that I describe more in that PR.

I still believe that this is useful, for the quantity of free improvements it brings: https://github.com/WebAssembly/binaryen#binaryen-optimizations