sots-re/findings/control-flow/fleet-visit-order-mechanism.md

What orders the fleet-assignment visit? — the container hook on ad-turn27

• Owner / date: lane BU · 2026-09-09 · guest VM146 (sots-re-win10-146, re@192.168.10.146)
• Held: VM146, from the time this prediction was committed. VM140 (reference, exclusive), VM141 (lane AZ) and VM144 (lane BS) untouched; lane BT is on the host in verify/state-checksum/ and is not touched either.
• Trigger: findings/control-flow/ai-visit-order-probe.md §4.1 — lane BR's closing paragraph, which killed H2 by measurement and named this lane's work in one sentence: one bounded static read of AssignFleetsAndIssueOrders 0x006c16c0 and the gathering hub to place a hook, log (element address, systemId, minted fleetId) in visit order, two fresh processes. Frame: findings/resolutions/2026-09-09-fleet-id-order-residue.md §2.2 / §3 / §4.
• Build: bu-55408a9-20260909T071101Z, built in /srv/re-lab/build/sots-engine-bu after ssh spicy 'pct exec 111 -- rm -rf …' of the whole tree (rule 24), from a lane-private git worktree at ~/sots-engine-bu (branch wip/bu, commit 55408a9) with no local build* shipped (rule 21). binkw32.dll sha256 117c150a4dbd7f240ada7b8416917ad67eb9f239682dc7370a8a521e0c0956d5. Deployed to C:\SOTS\shimdist-bu.
• Input: C:\SOTS\SavedGames\ad-turn27-two-raiders.sav, sha256 1c8baa27680809d585ab1728391e82729642d32aaedffd5bf95b616f0a11a436, 100,809 B — re-verified on the guest before the deploy, equal to lane AD's, BP's and BR's published value.
• Route: load (ad-turn27-two-raiders.sav → one End Turn), held fixed, as in BP and BR, so this lane is unconfounded by lane BQ's per-history input (resolution §9.1).

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0. Where the chain stands, in one paragraph

Two processes with identical pinned AI client seeds write autosaves differing in exactly 35 of 61,147 leaves, and all 35 are one transposition: two newly formed fleets exchange contents. The command blocks differ in exactly three words. The fleet-id counter is deterministic — 1970, 1986, 2002 are minted in that order in every process. What varies is the order in which the fleet-assignment pass visits the ship groups that need a new fleet. Lane BR then excluded RNG by measurement: across all three AI clients' OnResumePlaying brackets foreign_words=0, foreign_calls=0, residual=0, left_delta == observed (so not an inlined draw either), and the per-process global generator at 0x00af6e58 was drawn exactly three times in the whole process, from one return address, minting the three client seeds and doing nothing else. H2 is dead. What is left is H1 — an address-keyed container walked in heap order — or H1b — a comparator reading an uninitialised word, where the order is a function of nothing in particular. BR also measured that LFH randomisation is live here (four processes, four relative orders for one identical allocation sequence) and that the emitted command nodes' address order does not track the visit order, so the block cannot substitute for the hook. This lane places the hook.

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1. The bounded static read, and what it bought

Read to place a hook, not to derive an answer (rule 18). Recorded here because the hook's validity rests on it, and because two of its three facts are new to the record.

1.1 Rule 17, discharged first

AssignFleetsAndIssueOrders was disassembled from dumps/sots.exe to the next function start, not to Ghidra's reported size. The real body is 0x006c16c0–0x006c247a ret; Ghidra's sizeInBytes (3504) and endAddress (0x006c247a) agree with the ret — but immediately after it sits a four-entry jump table at 0x006c247c, the target of jmp [eax*4+0x6c247c] at 0x006c22fb, followed by int3 padding to the next function start 0x006c2490. So a sweep clipped at fva + sizeInBytes loses the table, which is the same class of defect rule 17 names even though the ret itself was reported correctly this time.

1.2 The walk, and why the loop body is not the hook

param_4 is the std::vector<StarFleet*> that AcquireFleetsForTask filled (its [ebp-0x3c] result, per AI3). The function walks it three times:

loop	range	per element it calls	order
head	0x006c1730–0x006c1740, once at entry, before the pass gate	0x006a4290	vector index order
element	body at 0x006c17e0, cursor at [ebp-0x38]	the assignment work	vector index order
tail	0x006c1760–0x006c1770, entered at 0x006c1753 after the element loop is exhausted (jmp 0x6c1753 at 0x006c21c4)	0x0069da10	vector index order

The element loop's cursor is advanced by add eax,0x4 at 0x006c21b5 and compared against _Mylast refetched from [param_4+4] every iteration (0x006c21bb), with the back-edge jne 0x6c17e0 at 0x006c21be. So the visit order is the vector's index order and nothing inside the loop can reorder it — which relocates the question, correctly, to whatever filled the vector.

Patching the loop body would be a mid-function detour whose first instruction (0x006c17e6) is a branch target — from jne 0x6c17e6 at 0x006c174d, the first iteration's entry — so a 5-byte patch at the body head would corrupt the first pass through it. That is exactly the shape rule 19 exists for, and it is unnecessary:

0x006a4290 and 0x0069da10 each have EXACTLY ONE CALLER in the whole image, and that caller is AssignFleetsAndIssueOrders. (Ghidra cross-references: totalToCount = 1 for both.)

They are ordinary function entries, called once per element, in the same order the element loop will follow. Two entry detours therefore record the walk with no return-address filter, no mid-function patch, and no traffic from anywhere else in the game. A third detour on 0x006c16c0 itself brackets them, so each burst of element rows is attributed to (agent, task, pass, vector) rather than inferred from where the bursts fall — and pass matters, because the emitting body is pass-1-only while the head loop runs on both passes.

1.3 What the two callees are, and the layout they confirm

Both read the element's ships vector at [fleet+0xa8] − [fleet+0xa4] and each ship's id at [ship+0x4], which independently confirms StarFleet_off_Ships (+0xa4/+0xa8) and gives the ship id the same offset as StarFleet_off_Id. They are exact inverses over a std::vector<int> at agent+0x2d8 (_Myfirst +0x2d8, _Mylast +0x2dc, _Myend +0x2e0):

• 0x006a4290 = ClaimShipsOfFleet — for each ship, linear-scan the agent's id vector (0x006a42e0) and push_back the id if absent, with the MSVC grow path (capacity check against 0x3ffffffe, reallocate through 0x00483410);
• 0x0069da10 = ReleaseShipsOfFleet — find the id, memmove the tail down (import 0x009dd30c), [agent+0x2dc] -= 4. RET 4.

So the fleets acquired for a task have their ships' ids parked on the agent for the duration of the assignment walk and removed when it is done. New names, filed in ghidra/addresses.d/bu.json with the offset; AssignFleetsAndIssueOrders is not re-declared there (lane AI3 owns it, and gen_addresses.py rejects a same-address-different-name collision).

1.4 What the read did not settle, stated so nobody reads more into it

• Where the new fleet id is minted is still not located. IDMap::AllocateOnLocalNode 0x008b8b70 has six callers and IDMap::AllocateLocalID 0x0080f710 twenty-four, none of them in the AI band 0x0068–0x006e on a direct edge from this function. So this lane logs the minted id by joining to the block, not by hooking the mint. That is a gap in the read and it is recorded as one.
• The gathering hub was not read. The resolution's §4 allows reading it; it is not needed to place this hook, and rule 18 says stop. If the answer is H1, the container that ordered the vector lives in AcquireFleetsForTask 0x006ceef0 / GatherFleetsForTier 0x006abf80 / 0x006b7c90 / 0x006cb310 and is stage 3, not this lane.
• Nothing here says the four list-10 groups are visited inside one call. They may be one vector in one task's call, or four bursts across four task calls. The instrument is agnostic: the bracket row records the call, and the element rows record the order within it, so both readings are visible in the same log. §2.3 predicts for both.

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2. The predictions, committed before the run

Committed in their own commit, with no result in the file (rule 2).

P0 (the instrument, checked before any output file is opened). shim.log reads BUILD_ID bu-55408a9-20260909T071101Z; 28 of 28 registered hooks mode=off; zero ignoring unknown key; zero COVERAGE:; aiseed call=1/2/3 … pinned=1 with no pinned=0, no PIN MODE WITH NO PINS and no used=0xdeadbeef wildcard hit; and three aivisit: … create=MH_OK enable=MH_OK lines. Any miss and the run is void and nothing is read from it.

P1 (the outcome set, rule 19's own check). (Autosave).sav ∈ {e913ff41188211c02d536da616337544e64133996cd7cc7a6521a8df1960226f, 724528ffde9a7514b69ab9e82ed3b8c8ade63d622c0720de30503a73a92df11e} in both runs, and the pre-turn (Autosave EndTurn).sav = 16f63adbf383946db17c381998957172bca803406b7df78f3b03805fef0bbcb8 in both. A third file is ambiguous between k ≥ 3 and the three aivisit detours perturbing the run and does not immediately mean either; §2.4 names the disambiguation and this lane will run it rather than pick a story.

P2 (rule 26 (d), the pin's own control). At least one of the two runs is byte-identical to lane BP's unpinned run L (e913ff41…), which is the natural run whose observed seeds this lane's pin uses. Until that holds, nothing is read from a pinned pair. If both runs land on 724528ff… the control is unmet and this lane says so and takes a third process rather than reading the pair anyway.

P3 — THE HEADLINE, AND IT IS THE COMMITTED PREDICTION THE BRIEF ASKS FOR. The visit order is ascending element address. Concretely, in each run and for the burst that covers the groups list 10 records:

• elem in the aivisit claim rows is strictly increasing with idx;
• the aivisit slots row (the vector's storage read straight out of param_4) is the same sequence, so the two independent readings agree;
• the aivisit rel rows are the same order as the claim rows for the same call, i.e. the vector was not permuted during the walk;
• and across the two processes, the element order differs exactly where the visit order differs. If run 1 lands on e913ff41… (list 10 = (384,1970) (80,1986) (384,2002) (816,7072), system 384 first) and run 2 on 724528ff… ((80,1970) (384,1986) …, system 80 first), then the system-384 group's element address is below the system-80 group's in run 1 and above it in run 2. If both runs land on the same file, both must show the same relative address order, which is the weaker but still falsifiable form.

P4 (the join). Every aivisit claim row's ships=[…] id set contains the ship id list of exactly one list-10 element of the same block, and that mapping is injective. This is what makes the pairing of element address to (systemId, fleetId) a measurement rather than an assumption about position.

P5 (the block, inherited unchanged from BP and BR). The aiorders dump has 9 blocks and 81 elements, the same (pid, list, idx) key set and the same per-list counts (player 32 emitting {1:3, 3:19, 5:15, 7:2, 8:3, 10:4, 12:12, 14:8, 23:15}), and differs from BP's runs A and B only inside the proven noise mask plus, at most, the three transposition words.

2.1 How each of these could be wrong, and the symptom

way	symptom	what it would mean
H1 is right	P3 holds: elem ascending with idx, and the two processes' address orders differ exactly where their visit orders do	The container is address-keyed. The engine's deliverable 2 (a canonical order that is a function of the save alone) is confirmed as the right fix, and stage 3 is naming the container inside the gathering hub.
H1b is right	P3 falsified: elem is not monotone in idx, and the order tracks neither address nor id	An uninitialised-word comparator, or some third key. The next separation is named in §2.4 and it is cheap.
a third possibility this lane must not hide	elem ascending in both runs and both runs land on the same file, so nothing distinguishes	P3 holds only in its weak form. It is consistent with H1 and does not test it. Reported as a weak result, not a confirmation, and the fix is a third process.
the walk is one burst per task, not one vector	the bracket rows show four calls with one element each	Then the varying order is the task order, not a within-vector order, and the address to test is the task pointer, which the bracket row also carries (task=). The instrument survives; the H1 test moves to that column and this file will say so.
a wrong offset	fid=0, nships=0 or an empty ships=[] on rows whose fleets plainly have ships	The reads are probed, so this shows as a logged zero, never a fault. The join (P4) fails visibly rather than silently, and the run is reported as an instrument failure.
the hook perturbs the turn (rule 19)	a third autosave file	Not separable from k ≥ 3 by these runs alone. §2.4.
the pin is half-applied	any pinned=0, a PIN MODE WITH NO PINS line, or a used=deadbeef hit	The run is void. Checked in shim.log before any output file is opened.
a stale or wrong binary (rule 24)	BUILD_ID ≠ bu-55408a9-20260909T071101Z	Void. The CT111 tree was rm -rf'd before the rsync and the build was re-run from the lane commit.
the config carries an inherited defect	a live line inside what was meant to be a comment; an unnamed registered hook silently installed under hooks=trace	Defended twice: tools/check_shim_configs.py passes with shim.cfg.bupin marked # exhaustive, and the non-comment diff against the file it was copied from is quoted in §2.2.

2.2 The config, and the two diffs (BP's check, and it has caught a real defect)

shim.cfg.bupin is shim.cfg.bppin with exactly three non-comment lines added. Taken against the real shim.cfg.bppin pulled off the guest, not against a local copy of it:

$ diff <(grep -v '^\s*#' shim.cfg.bppin | grep -v '^\s*$') \
       <(grep -v '^\s*#' shim.cfg.bupin | grep -v '^\s*$')
7a8,10
> aivisit=on
> aivisit.out=C:\SOTS\shim.aivisit.txt
> aivisit.ships=8

bppin has 43 live lines, bupin 46. And against shim.cfg.brprobe, the file this lane actually copied (BR's, which is bppin plus the three airng lines), the diff is six lines and shows the airng bracket being taken back out:

$ diff <(grep -v '^\s*#' shim.cfg.brprobe | grep -v '^\s*$') \
       <(grep -v '^\s*#' shim.cfg.bupin | grep -v '^\s*$')
6,8c6
< airng=on
< airng.pin_seed=off
< airng.out=C:\SOTS\shim.airng.txt
---
> airng=off
9a8,10
> aivisit=on
> aivisit.out=C:\SOTS\shim.aivisit.txt
> aivisit.ships=8

airng is off deliberately: BR already took the per-client ledger on this exact state and it came back clean, so re-installing that bracket would be three more detours for an answer already in hand. Everything else is byte-for-byte BP's: hooks=trace, all 28 registered hooks off by name, aiorders=on with deep=off and words=12, aiprobes=off, airesearch=off, aiseed=pin with 32=156ebbbd,496=fe7b2826,512=0ed341d1,*=deadbeef.

And the structural check the resolution asked for is now enforced, not remembered. shim.cfg.bupin carries a line reading exactly # exhaustive, so tools/check_shim_configs.py requires it to name every registered hook:

$ tools/check_shim_configs.py
check_shim_configs: OK (27 registered hooks, 2 template(s) declared exhaustive)

(27 is the count excluding the self-test hooks the checker exempts; the file carries 28 hook.* lines, the 28th being Shim::SelfTest::Fill.)

2.3 The instrument, stated in full (rule 19 wants the list, not the adjective)

Installed, and nothing else: the Mars::Application::Initialize detour; the seven draw-site detours (unconditional whenever hooks != off); one aiorders detour on StrategySim::ApplyTurnCommandBatch; one aiseed detour on StrategyApp::RunAI; and three new aivisit detours. That is BP's instrument plus three. All three new targets are function entries; two of the three are called from exactly one place in the image and that place is the third. No airng bracket, no facades, no entry probes, no watchpoints, no research hooks.

2.4 The disambiguations, named before the run so they cannot be chosen after it

• A third autosave file → one plain run of shim.cfg.bppin (this lane's aivisit lines removed, everything else identical). Under the k ≥ 3 reading that run cannot land on a third distinct file with probability better than 1/3; under the perturbation reading it lands on one of BP's two. This is BR's own procedure and it is adopted verbatim.
• P3 falsified (H1b) → the next separation is whether the order tracks the ids: the element rows already carry fid and the ship id set, so "ascending fleet id" and "ascending minimum ship id" are testable from the same log with no further run. If the order tracks neither address nor id, the key is a word nothing in the save determines, and the follow-up is a watchpoint on the comparator inside the gathering hub — a different lane and a different instrument.
• P2 unmet (both runs on 724528ff…) → a third process, and no reading of the pair until one of them reproduces run L.

2.5 What this lane cannot decide, whatever it says

One save, one procedure, one build, one route (load), one turn. It can say what the visit order is a function of on this turn; it cannot name the container that produced it (that is stage 3, in the gathering hub), it cannot speak about a turn that acquires fleets by a different gather block, and it says nothing about lane BQ's per-history residue, which is a different input in the same layer. The 3–40-turn fuse at 0x0069dbb0 cannot fire inside one turn of a load and is untested here, exactly as in BP and BR.

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3. The result

(To be filled in after the runs. This section is empty in the commit that carries the prediction.)