A method and apparatus to optimize a list of vector instructions using dynamic programming, in particular memoization, by generating a table containing instruction subvectors having individual (parts), contiguous (superparts) and repeated (broadcasts) lanes. Because the instructions in the table are subvectors selected to have individual, contiguous and repeated lanes in the registers, compiler optimizations can be enhanced. Introduction of such dynamic programming allows for speculative lane optimizations, as well as improved analysis-guided optimizations, either of which can be performed alone or in combination with other optimizations, whether or not they make use of dynamic programming.