Since #180397, all elements of a `DenseIntOrFPElementsAttr` are padded to full bytes. This enables additional simplifications: whether a `DenseIntOrFPElementsAttr` is a splat or not can now be inferred from the size of the buffer. This was not possible before because a single byte sometimes contained multiple `i1` elements. Discussion: https://discourse.llvm.org/t/denseelementsattr-i1-element-type/62525