A recent commit (https://reviews.llvm.org/rG66c120f02560ef528a60924104ead66f330190f1) changed the cost for calls to functions that have a vector version for some vectorization factor. However, no check is performed for whether the vectorization factor matches the current one being cost modeled. This leads to attempts to widen call instructions to a vectorization factor for which such a function does not exist, which in turn leads to an assertion failure.
This patch adds the check for vectorization factor (i.e. not just that the called function has a vector version for some VF, but that it has a vector version for this VF).