wazero's intermediate representation (IR) is called wazeroir. Compiling into an IR provides us a faster interpreter
and a building block for a future JIT compilation engine. Both of these help answer demands for a more performant
runtime vs interpreting Wasm directly (the naivevm interpreter).
wazeroir's initial design borrowed heavily from the defunct microwasm format (a.k.a. LightbeamIR). Notably,
wazeroir doesn't have block operations: this simplifies the implementation.
Note: microwasm was never specified formally, and only exists in a historical codebase of wasmtime:
https://github.com/bytecodealliance/wasmtime/blob/v0.29.0/crates/lightbeam/src/microwasm.rs