Yakiv Shavidze

This work gives three structural results with proofs and bit-perfect verification - that the repeat-distance chain of an LZ77 parse forms a substitution monoid and is therefore prefix-scannable without touching the bitstream, that self-overlapping matches are periodic rather than chained, and that dependency depth admits an encoder-enforced bound.

Parsing, not copying, dominates GPU LZ77 decode time, challenging long-held assumptions and revealing new avenues for optimization.

Increasing the minimum match length can simultaneously boost both compression efficiency and decode speed, achieving up to a 78% throughput increase without any kernel modifications.