Clif ir and vcode/asm inspector

[bjorn3]

This inspector allow you to pick a single function and then present the clif ir (before and after optimization) and compiled vcode/asm of said function. It should also show the mapping between clif ir and vcode instructions in a way similar to godbolt's compiler explorer. As a bonus it could also show the original rust source and the mir of the compiled function. Preferably the inspector would be usable for other Cranelift users too if they dump all necessary info in the right format.

[mmcloughlin]

This would be a great feature.

Short of a nice GUI, is there a way to dump the intermediate CLIF code right now for inspection? Forgive me if I've missed something in the documentation, it's not come up in my searching so far. Thanks.

[bjorn3]

You can pass --emit llvm-ir to rustc. Yes, it is poorly named. Rustc has a fixed set of values it allows for --emit without changing rustc itself, so I picked the value that does something equivalent in the LLVM backend to dump clif ir in the Cranelift backend.

[mmcloughlin]

Ah, makes sense! Thank you!