1. A program product, comprising: a computer readable storage medium; and program code stored within the computer-readable storage medium and executable by a computer system, said program code configured to cause the computer system to perform: analyzing pre-processed code, wherein the analyzing includes: identifying at least one storage-modifying construct specifying a storage-modifying memory access to a memory hierarchy of a data processing system; and determining if more than one granule of a cache line of data containing multiple granules that is targeted by said at least one storage-modifying construct is subsequently referenced by said pre-processed code; and generating post-processed code including a storage-modifying instruction corresponding to the at least one storage-modifying construct in the pre-processed code, wherein the generating includes marking the storage-modifying instruction with a partial cache line hint indicating that said storage-modifying instruction targets less than a full cache line of data within a memory hierarchy if the analyzing indicates only one granule of the target cache line will be accessed while the cache line is held in the cache memory and otherwise refraining from marking the storage-modifying instruction with the partial cache line hint.