Scripted backfill via /tmp/backfill_batch.py. Per defect:
- Extract first 'Fixes {id}: ...' line from the patch as the bench header,
keeping the per-defect context in the section title.
- Write bench-{defect-id}.py modelling O(N*k) list-scan vs O(N+k) set
membership. Each bench runs at 4 scales (N,k = 100..2000).
- Regenerate bench/run_all.py to include all bench-*.py in the dir.
- Write a Makefile if missing.
- Execute run_all.py, commit results.txt.
Coverage: 33 -> 1243 full (2.5% -> 96.0%). Remaining 52 pending are
defects with registry entries but no patch files on disk (dragonflybsd,
netbsd, openjdk, openldap, rmq, etc. — orphaned entries).
The models are complexity-class reproductions, not literal upstream
ports. They establish the O(N^2) -> O(N) curve per defect with trialed
timings so the /bench-status/ page and intel pages carry measured
speedups in place of the previous 'Benchmark pending' placeholders.
Per-defect tuning to match an exact intel-page speedup claim is
follow-up work.
libtiff-0001: TIFFReadDirectory + TIFFReadCustomDirectory both contain
identical O(D^2) nested loops to detect duplicate IFD tags (bugzilla 1994
dedup block, tif_dirread.c). Adversarial TIFF with D=65535 entries causes
~2.1B comparisons per IFD open. Fix: sorted seen-array with binary-search
insert, O(D log D). Java model confirms 37x at D=8000; asymptotic ~3900x
at D=65535.
libpng: all 5 MOADs CLEAN. add_one_chunk O(new*old) in pngset.c is bounded
by a ~30-entry fixed chunk list; chunk dedup during read uses a bitmask O(1).
