Debug session alt-potential-4x-slowdown, root cause RC-1 (LIVE correctness
bug): bound()'s per-node sentinel skip (tv === 0xffff -> drop landmark l)
varied the active landmark family set PER NODE, so the toTable max lost
cross-edge consistency across edges leaving the 6,285-node disconnected
island (2.02% of cells) — shipped routeAstar returned suboptimal seconds
on 1/194 fresh random real-graph pairs vs the Dijkstra oracle (worst
single-edge family variance 1,026 s). D-03's fixed corpus was green on
sampling luck.
The fix (reverseFor precedent, in-constraint):
- per-graph WeakMap memo cleanColumnsFor: clean[l] = 'to-column l has ZERO
sentinel cells' — O(L*n) sequential row scans once per graph/isolate
- per-search active list activeL = clean columns only; bound() loops the
active list with NO per-node sentinel branch; the constant-table
goal/origin NaN checks are retained (belt)
- on the current binary (0/24 clean columns) potentials degrade to EXACTLY
haversine — the designed sound fallback; the pre-ALT CPU band returns
- ALT stays live and tested on strongly connected fixtures (mini-graph
0/2 dirty columns, A12 ring all-clean, new A13 mixed subset case)
- LANDMARK_SENTINEL_U16 named constant; sentinel compares at setup scope
only; pure-module law untouched
BH stop rule, reductions, balanced alternation, meet probes, real-seconds
reconstruction: UNTOUCHED. F2 (transposed table) explicitly out of scope.
Battery: routing 81/81 (A11 RED pins now green, A13 new), bot 126/126,
routing+bot typecheck clean.
araharah-executor
2a5a0b5b6a