Injects instrumentation bytecode directly into Wasm bytecode to perform some simple dynamic analyses. Built using Walrus, a Wasm transformation library.

This was implemented as part of an experiment comparing various instrumentation implementations with the instrumentation capabilities offered by the Wizard Engine.

• Hotness monitor: Inserts counting bytecode at every instruction and then produces a summary of hot execution paths.

• Branch monitor: Instruments all if, br_if and br_table instructions in the program and uses the top-of-stack to predict the direction each branch will take.

./wasm-bytecode-instrumenter <monitor> <filename>

This should generate a new Wasm program injected with instrumentation bytecode that you can run using any Wasm engine that supports multi-memory as it uses a separate memory region to store counts.

• Print captured info
• Loop monitor

WIP