3a56cc6998
Read straight off the drain, immediately after the pop:
8226D7AC lwz r11, 92(r31) ; payload+24
8226D7B8 cmpli cr6, 0, r11, 0x1
8226D7C4 bc 12, lt, 0x8226D89C ; +24 == 0 -> the SPAWN path
8226D7C8 bc 4, eq, 0x8226DA44 ; +24 > 1 -> bail
; +24 == 1 -> fall through, a NON-spawn path
So the field I recorded last iteration as "kind-tag shaped, but the drain was not
shown branching on it" does branch on it, three ways.
+24 = 0, written by built-in 19: condition sub_8226DAF8, then bl 0x822737C8 --
+28 is a code offset, matching the 79/79-vs-27.8%-control measurement.
+24 = 1, written by built-in 25: condition sub_8226DC80, no spawn, and the path
resolves +28 through [phase+244] -- symbol table 1:
8226D834 lwz r10, 112(r31) ; payload+28
8226D838 lwz r11, 244(r29) ; symtab 1
8226D848 lwzx r10, r10, r11
And that resolution checks out: over all 25 call sites disc-wide, built-in 25's
local[12] resolves to a symbol-table-1 entry 25 times out of 25, and every name is a
route -- Route_ADS101_p1F, Route_ADT107_p1F, Route_TCN004_p1S, Route_ADT202A_p2S.
The 1-12 values that looked like a puzzle two iterations ago are simply small symbol
indices. This independently confirms isl.py's SYM1_SLOTS, which lists slot 12 for
built-in 25 and was derived from operand ranges alone.
So there are two kinds of trigger: built-in 19 registers one whose payload is a
HANDLER ROUTINE, built-in 25 one whose payload is a ROUTE.
All artefacts regenerate byte-identical; documentation only.
Unread: both condition testers (sub_8226DAF8, sub_8226DC80), what the kind-1 path
does with the route past sub_8217FA08 / sub_8218CC88 / sub_8225FEA0, and the drain's
second spawn site at 0x8226DA10.