65d59b4265
LoopSimplify only requires that the loop predecessor has a single successor and is safe to hoist into -- it doesn't necessarily have to be an unconditional BranchInst. Adjust LoopDeletion to assert conditions closer to what it actually needs for correctness, namely a single successor and a side-effect-free terminator (as the terminator is getting dropped). Fixes https://github.com/llvm/llvm-project/issues/56266.