G1 card T03 - DIAGNOSTIC: inventory of the hidden records in _custom_render_nav_point's region 29 (HEAD and N3)
Written 2026-09-26 02:03:29 -0700 (clock-read), BEFORE the traces. Never edited.

T02 OUTCOME (facts; runs T02_{HEAD,N1,N3}_region, all stock_equal true):
  region 29 starts at +0x467 in all three. HEAD: region 29 ends on a hidden node, region 30 starts with push0#1
  (@0x590 after the hoisted loads). N1 (one decoration stripped): region 29's last node is push0#1 (@0x58a),
  region 30 starts @0x592 (= January). N3 (both stripped): region 29 ends @0x58c (push0#2), region 30 @0x594.
  Prediction (a) 'one removed 0x267 record = the region boundary moves one record later' CONFIRMED.
  So the whole +0x58A residual = January's region 29 holds exactly ONE hidden record fewer than HEAD between +0x467
  and the push window (emitted records there are byte-identical), equivalently one MORE than N3.

QUESTION: which hidden records does HEAD's region 29 hold (count, opcode, statement), so that the reopen criterion
names the January fact precisely (which statement of January's source has one hidden record less than ours / one
more than the natural N3)?
INSTRUMENT: w6trace.py 'sched' mode on HEAD and N3 (fresh dirs T03_{HEAD,N3}_sched), W6 schedsel.py over the cycles
of region 29 (+0x467..+0x58c), '--op 267' and full listing.
PREDICTION: HEAD region 29 holds the two bitmap_extent 0x267 temps plus k other hidden records (k >= 1, e.g. the
fast_ftol inline-parameter temp or the pow/fmod casts); N3 holds k. No candidate can come out of this card.
