llvm::isSplatValue

Return true if each element of the vector value V is poisoned or equal to every other non‐poisoned element. If an index element is specified, either every element of the vector is poisoned or the element at that index is not poisoned and equal to every other non‐poisoned element. This may be more powerful than the related getSplatValue() because it is not limited by finding a scalar source value to a splatted vector.