It currently requires that the condition match the shape of the selected value, but this is only really useful for things like masks. This revision allows for the use of i1 to mean that all of the vector/tensor is selected. This also matches the behavior of LLVM select. A benefit of this change is that transformations that want to generate selects, like those on the CFG, don't have to special case vector/tensor. Previously the only way to generate a select from an i1 was to use a splat, but that doesn't support dynamically shaped/unranked tensors.
Depends On D78683