findings/objects/turncommands-block.md -- why lane W's 44-item recovery and the
save's 35/38/41/61/123 items disagreed, in mechanism terms, plus the per-list
element records read off all 22 distinct helper writers.
Three separate causes, only one of which was a branch:
* layouts.md is OFFSET-SORTED and Game::TurnCommands is one of the 89 classes
whose offset order is not write order, because each gate bool sits after the
payload it gates. Align saves against streams.json, never layouts.md.
* the writer's tail is 27 std::list members, each written by its own helper as
WriteInt(size) then size element records. The linear recovery keeps one item
per CALL SITE, guesses its kind from an element field and drops the count.
44 - 17 members = 27 = the list count.
* 8 prologue items + 27 zero counts = the 35-item empty block, which is why
every earlier save was bit-identical here.
Corrects lane O's section 11 in place: the fleet-move element is
{fleetId, nHops, nHops x systemId} -- a counted route vector, not a fixed
{fleetId, 1, destSystemId, 0}. Only the three-item reading makes the item totals
close (a four-item element needs 26 lists on human-turn2 and 28 on zuul-turn15;
the writer has 27). Also records that neither noderoute save carries a fleet
move, so the node-route UI does not queue through that list.
22 of the 27 lists are labelled hypotheses: read off the instruction stream, but
no save exercises them and no element value has ever been observed. List 14 is
observed but not understood -- issuing one fleet move also queues
{sameFleetId, 0, true} there.
save_reader.py deliberately left alone, with the reasoning written down: it reads
CD generically for the AIAgent bodies too, state_checksum's digest tree is built
from the generic tree so typing CD would add no named leaf to any diff, dispatch
by CDT ordinal would need new machinery in the oracle, and rule 8 is pointed at
exactly this move -- a layout mirrored into both readers from one reading is not
two checks. coverage: PROVED, 0 error 0 warn on all eleven saves, unchanged.
ghidra/addresses.d/lane-q.json: 6 entries (the writer, its Read pair, and the
four observed list helpers). Validated by generating to a scratch path; the
tracked header was not regenerated.
Produces the game states several board rows were blocked on, and reads each
one back out of the save before claiming it.
- CD/TurnCommands_v5 decoded: three saves with issued orders (research target,
research boost, build orders, system rates, colonize, fleet move). Layout in
SAVE_FORMAT.md section 11; ids cross-checked against the same file's Sys/Flt.
- Waypoint type 3 (NodeRoute) now has 16 instances in one save and the player's
own fleet is a mover in two. Type 2 is shown NOT to be produced by a Move
order for either node-drive race (Zuul and Human both emit type 3).
- research_roll_pending true at load in two saves; the ProcessTurn gate constant
at 0x00a2c788 is a float 0.5, so the flag survives into ProcessResearch only
while progress/cost <= 0.5 at the start of the turn.
- Budget tail: construction and a large maintenance are live; Nexp is empty in
all 11 saves and the 1.8 UI has no expense slider, so slot 12 looks dead.
VM140 restored to the original 8-file SavedGames set (autosaves byte-identical)
and left at the main menu; VM140 row set FREE.
Part 1 (notes side): findings/objects/svsctob-variants.md records the two maps
that are nowhere on the wire and were read out of the game -- EncID -> class
from a 23-entry dword jump table at 0x0052bf60 indexed by EncID-1 (0x0052bf00),
and xscn -> class from an exhaustive four-way _stricmp chain at 0x005a7050.
Twelve live EncIDs, four scenario names, and "indsys" =
Game::SVSOIndependentSystems whose Read and Write are both the shared `ret 4`
stub at 0x005f8ac0, so its empty frame is correct output rather than a
truncation. Also: SVSOSots::Read accepts NPCPlr and hastraps, which Write never
emits -- read-only backward compatibility, not a hole in the recovery. And a
correction to the recovery itself: SVSOCrowDefenders writes `dsys` INSIDE the
ndsys loop; layouts.json calls it a plain member and no save can settle it
because both counts are 0 everywhere. 13 addresses in ghidra/addresses.d/
lane-w.json; gen_addresses.py merges to 640 with no duplicate name.
Part 2: lane G found four defects in both readers and deliberately did not
patch the oracle mid-campaign. Fixed now, with tests, and byte-neutral.
1. Game::SystemParams field 1 is a string, not an int (empty string == four
zero bytes == int 0, so it round-tripped by luck).
2. ObservedTech/ObservedWeapon odet is a bool, not an int (byte-safe only
because a 4-char tag makes both items 12 bytes; 3 chars would not).
3. SpeciesRatios nv is a count, not a field.
4. ShipRecords srbd is a count, not a field -- and this one is behaviourally
confirmed, not inferred: srbd takes 0, 1, 3 and 4 across the players and
every non-zero count is followed by exactly srbd x 5 scalars.
Note that 3 and 4 were an ABSENCE in save_reader.py, not an error: ShipRecs and
civr were both A(..., "any"), so the fix had to add the shapes rather than
retype a field.
Byte-neutrality: every item's inflated offset is unchanged on all four saves
(38,933 / 39,843 / 40,300 / 35,771 offsets, sequences identical), so no item
boundary moved. state_checksum.py still reports coverage: PROVED on all four
with the same rebuilt byte counts. The /CreateParams and /Sim/players digests do
change, because they hash typed VALUES and two fixes change what a value is --
and the value-byte deltas balance exactly: odet items x 3 plus p1 items x 4.
--strict exit 0 on all four saves; tests 36 -> 48.
findings/objects/wire-schema-closeout.md carries the whole account, including
the proof that CD/TurnCommands_v5 cannot be typed without a save that has
issued orders.
Reads: TechTree::PrereqsMet 0x0057d8e0 (AND of ORs; zero groups TRUE, an empty
group FALSE), the prerequisite layout at TechDef+0x88/+0x98, the tail collector
0x00587cc3, and the head of OnTechResearched (RecordObservedTech unconditional;
the research-event roll gated on ResT == def && ResearchRollPending).
Live: 35 compared calls over three workloads, 0 divergences, tracecmp exit 0,
End-Turn oracle hashes unchanged. The EVENT_TECHS_UNLOCKED residual lane P
predicted and lane V measured is closed by running the cascade, not by posting
on completion.
12 new addresses in ghidra/addresses.d/lane-u.json (header 615 -> 627).
Lane P wrote the expected numbers into sots-engine docs/P-events-wiring.md §4 before
this run existed. Every one held.
First End Turn (ref-turn2 -> Launch -> End Turn, shim.cfg.recapb3 unchanged, build
eventlive-dd38117-20260908T0916Z, main dd38117 with no source change): 3 calls, 3
compared, 0 divergent, tracecmp exit 0 — where lane R's run exited 1 on
side.events.after.v.next_id orig=4 ours=3. Call 0 read turn=3,
events_turn_bucket_exists=true, events_next_id_in=3, events_in_turn_bucket=1,
events_dedup_risk=0, no events_scan_truncated, next_id 3->4 on both sides,
turns/turns_bytes 2/48 unchanged, node[144].progress 2879->5768, flag 1->2, rng
identical — the whole predicted list.
Five End Turns: exit 1 with 2 divergent calls instead of 3, each short by exactly 1
(next_id orig 7 ours 6, orig 12 ours 11) = the deliberately unmodelled
EVENT_TECHS_UNLOCKED. A 0-divergence result there would have been suspicious.
sizeof(Game::ObservedTech) = 44 measured live: observed_techs.bytes grew by exactly
44 on both completion calls (440->484, 484->528), confirming lane X's static pin
behaviourally. Non-researching players measured 880 = 20 x 44 and never moved.
One deviation from lane R, and it is a workload effect, not a defect: rng diverged on
call 9 because the completed tech had research_roll_pending set and the
OnTechResearched callback drew one word ours does not (left 374 vs 375). Lane R's
"RNG matched 15 of 15" was workload luck; the honest statement is that the rng region
matches on every call that does not complete a roll-triggering tech.
Zuul double roll CLOSED. No species-5 save existed, so this lane made one: a custom
game with only Zuul in the Available Species pool, 4 End Turns under the same compare
config. 8 calls, 8 compared, 0 divergent, exit 0; all four researching calls have
species=5 and advance the generator by two, not one (left 540->538, 522->520,
504->502, 485->483), and ours reproduced every post-state bit-for-bit. Save added as
verify/results/saves/zuul-turn5-species5.sav.
End-Turn oracle byte-identical to lane R's on the first turn, so none of this
perturbs the game. clean_room_check OK and host ctest 33/33, run as separate commands.
VM140 restored to the recap build at the main menu and released.
Settles the 0x18-vs-0x1c contradiction lane X raised. 0x1c is right, everywhere,
and there is exactly one std::string instantiation in this binary:
_Bx@0, _Mysize@0x10, _Myres@0x14, _Alval@0x18.
ObservedTech+0x24 is that string's trailing empty-allocator word, not the
unaccounted data field it was read as. Three complete enumerations of the element
each skip it: ObservedTech::Write 0x00817cf0, the ctor 0x008562a0, and the copy
ctor inlined at 0x0079a184. Generalised with a new scanner, tools/strfootprint.py,
which recovers every (base, disp, tag) handed to the Mars::Stream string helpers:
65 std::string members off a non-stack base across every serializer in the exe,
ZERO with a sibling member inside the 0x1c span, and 51 of the 52 measurable
inter-member gaps exactly 0x1c. Corroborated by the vector<string> walk stride
(add esi,0x1c @0x00699c29), PostEvent's by-value strings at [ebp+8]/[ebp+0x24]
with RET 0x4c, and MoraleEvent 0x50 = name@0x34 + 0x1c.
Blast radius: zero recovered struct tables were wrong. Every string-bearing layout
already used 0x1c spans and 0x1c gaps -- ServerPlayer::pswd @0x2dc..0x2f7, the row
flagged for re-checking, included. Only prose carried the 0x18 number: the
loader-prototypes conventions line, the GlobalConst_ParseString prototype, and the
ObservedTech element table. struct-recovery S0 additionally had _Mysize/_Myres
transposed (size@0x14, res@0x18) while every table in the same file used the
correct offsets; fixed.
ObservedTech's four on-disk fields are now mapped rather than guessed, by reading
the serializer as lane X suggested: +0x04 uint16 otnF, +0x06 uint16 otnL, +0x08
bool odet (ONE BYTE, WriteBool), +0x0c std::string otch (0x1c), +0x28 int owith
= 0x2c exactly. That matches save_reader.py's on-disk order already. Game::
ObservedWeapon (0x00817bc0/0x00817b10) is the same element with tag owep.
Oracles unaffected and re-run: save_reader 36/36 and --strict exit 0 on all three
real saves; state_checksum 38 tests OK, coverage PROVED byte-for-byte on turn1 and
turn3. sots-engine wip/strings 32d3e36 syncs the header and corrects two stale
"unpinned" comments: clean_room_check OK, host ctest 33/33.
Standing rule this produced: never size a struct member from the offsets the code
touches. This build's STL puts the empty allocator LAST in both string (0x1c) and
vector (0x10), and an empty allocator is never loaded or stored, so a touch-scan
undercounts by exactly 4 every time. Size from an enumeration instead.
Seven End Turns from ref-turn2.sav on VM140, six control words, whole-state
checksum on every post-turn autosave.
53-bit and 64-bit x87 give byte-identical state across all 35,394 leaves, so
an x64/SSE port computing in IEEE double has NO double-rounding budget to
preserve and floats=bits is free. Two settings do move state, each reproduced
on a repeat run:
0x007f (24-bit) Sys[112 "Gamma Cephei"]/Pop2/PopG/PopC 540000000 -> 540000002
0x1a7f (round-up) Flt[34 "Beta Fleet"]/Pos/.[0] and /Pos/.[2], 1 ULP each
So the port must hold intermediates at 53 bits and use round-to-nearest --
both SSE defaults, now measured rather than assumed, each with a named
regression witness.
The briefed triple was under-powered: 0x027f is 53-bit (it differs from 0x127f
only in bit 12, infinity control, ignored since the 387) and 0x137f is 64-bit,
not a rounding change. Run as written all three come back identical, and that
would have "proved" something false on both axes that matter.
Evidence the forced word actually held: read-back at each force site plus 38
independent in-pipeline hook samples per run spanning turn phases 4, 6 and 8,
all reading the forced value. Mars::Application::Run calls
_controlfp(0x50000,0x3070300) at 0x0089f606 every frame, which is 0x127f, so
forcing at StrategyClient::EndTurn is wiped before the turn runs;
StrategyServer::BeginProcessTurn is the point that works.
Also re-confirms the End-Turn determinism oracle on engine cef889e:
bb4fd9ac... / 978041ac... unchanged.
New tools: verify/fpu-cw/cw_census.py, verify/fpu-cw/trace_bitdiff.py (the
latter exists because under a forced 24-bit word the CRT's own %g rendering
degrades, so trace text is not a valid comparison surface).
The complement to the per-function compare harness. Instead of "did this
function's declared outputs match", it asks "is the entire simulation state
still identical" -- so no region-declaration mistake can hide from it.
Coverage is PROVED, not declared: the digest tree is re-serialised and compared
byte-for-byte against the inflated save on every run. When that reconstruction
reproduces the stream, the whole file is a function of the digest's inputs. A
run that cannot account for the file says so and exits non-zero. This is the
direct answer to B4's three hooks that printed "0 diverged" over an empty
region set.
It localises. The root is the fold of a per-subsystem / per-object tree with
named objects, so the known load->re-save delta reports as exactly five leaves
-- /Summary/Checksum and four /Sim/players/Player[...]/Status 4->0 -- naming the
two Singularity players by id where the raw byte diff could only say "1st of
two". One real End Turn reports as 108 fully attributed differences.
Float-parity policy is explicit and strict by default (STATE_CHECKSUM.md 3):
raw IEEE-754 bits; a `canonical` policy for signed zero and NaN payloads only;
and deliberately NO tolerant hashing mode, because quantisation moves the cliff
rather than removing it and destroys the roll-up. Tolerance lives in the differ
as --ulps, applied after localisation. Corpus census: 0 NaN, 0 -0.0, 0
subnormals across 4,474 float leaves, so the strict default costs nothing today
and a test fails the day that changes.
Validated on the real saves (verify/results/state-checksum/): 10 files, 4
distinct contents, all STABLE + COVERED; chain record/verify works on the real
turn1-3 saves. The VM-driven replay loop is designed (section 5) but UNRUN.
Section 3.5 names the one question the host side cannot settle -- whether the
turn pipeline depends on x87 intermediate precision -- and the experiment that
would: force fpu_cw to 0x027f / 0x127f / 0x137f across End Turn and checksum
the three autosaves.
Also recorded: Summary.Checksum is NOT a byte sum over the inflated stream nor
a sum over the int leaves (both ruled out), so nobody repeats those two.
38 tests; sots-engine untouched, clean_room_check.sh OK.
Five hooks recaptured, build recap-7584bad-20260908T0615Z, no source change.
- ProcessResearch: the over-budget event is now a compare divergence
(side.events.after.v.next_id orig=4 ours=3) instead of a 609 KB save diff.
15 calls over 5 turns, 3 diverged, RNG matched 15/15.
- ComputeBudget: 4284 compared, 0 diverged, guard quiet - but only 20 distinct
states and 13 of 22 slots always zero.
- MoveFleet: 8 of 45 calls diverge by 1 ULP of position. B4's clean verdict was
a one-sample verdict.
- First guarded captures for OnTechResearched (RollResearchEvent draw fired and
matched), the colony turn and MoveFleet.
- Guards mapped SetResearched live and found an undeclared ObservedTech append.
VM140 released at the main menu, hooks=trace.
