A method and apparatus for optimizing exact garbage collection, using loop operation on pointer arrays

摘要

Apparatus, methods, systems and computer program products are disclosed that optimize a programmed loop that stores pointer variables in an array in a card-marked heap. These methods also optimize garbage collection operations on these pointer variables. Instead of implementing a write-barrier in the body of a programmed loop, the loop is pararneterized. This parameterization is associated with the pointer array stored in the heap. This parameterization specifies the first and last modified elements in the array. It further specifies the stride (which indicates how many elements are skipped to reach the next modified element of the array). The parameterization is modified by successive loops that access the array. During a garbage collection operation, the array's pararneterization is used to optimize the process of locating modified elements in the array.