Wasm’s structured blocks are a nice constraint, but irreducible CFGs are where the compiler has to choose between cloning code and introducing a dispatcher.
Yeah, and one thing that has been unclear to the WebAssembly CG is what is the performance and binary size impact of not allowing irreducible code. People can write microbenchmarks that show an impact, but we don't have great real world data.
So right now it's not a priority to fix. But the door is open to allowing it in the future.
Wasm’s structured blocks are a nice constraint, but irreducible CFGs are where the compiler has to choose between cloning code and introducing a dispatcher.
Yeah, and one thing that has been unclear to the WebAssembly CG is what is the performance and binary size impact of not allowing irreducible code. People can write microbenchmarks that show an impact, but we don't have great real world data.
So right now it's not a priority to fix. But the door is open to allowing it in the future.