A mechanism is disclosed for offset-based addressing in the chunks of a
chunked heap. The mechanism provides for storing a side data structure
within a portion of a chunk, where the side data structure begins at a
predetermined offset within the range of virtual memory addresses
allocated to the chunk. The side data structure comprises a plurality of
entries, where each entry is associated with a corresponding section of
the chunk. The mechanism provides for locating a particular entry in the
side data structure corresponding to a particular section of the chunk by
using the predetermined offset and an index derived based on the
particular section, where locating the particular entry does not include
performing any memory accessing operations or conditional branch
operations to obtain an indirect reference to the side data structure.