wasmer [1] has a LLVM backend, WAVM [2] uses LLVM as the bakend, I could be wrong but last time I checked, cranelift is only meant to be the next generation WASM engine used in Firefox, it is not yet in production.
And actually the argument is: all of v8, Firefox/Cranelift and LLVM used in wasmer requires non-trivial work to make WASM fast, which shouldn't be needed given a different model.
I highly doubt that there is another model that would not require non-trivial work to be fast, while also being reasonably portable to different architectures.
Sure, we could be faster by just sending x86 machine code, but that isn't really the point.
And actually the argument is: all of v8, Firefox/Cranelift and LLVM used in wasmer requires non-trivial work to make WASM fast, which shouldn't be needed given a different model.
[1] https://github.com/wasmerio/wasmer/tree/master/lib/llvm-back... [2] https://github.com/WAVM/WAVM