sots-re/ghidra/addresses.d/lane-l5.json
alex ea7881acb3 L5: the money chain's float widths, measured live at a boundary
Four float constants in ComputeBudget have a width a C++ port gets wrong by
default, and the corpus exercises the boundary of exactly one. That one is now
measured against the running game, with a control build that must fail and does.

  savings interest   (double)0.01f   boundary: treasury a multiple of 100   IN CORPUS
  debt interest      (double)0.15f   boundary: a negative treasury          not in corpus
  research yield     (double)0.85f   boundary: research money mult of 40k   not in corpus
  the three ResMod   summed in f32   boundary: two of three non-zero        not in corpus

Three constants sitting beside those, in the same expressions, are EXACT doubles
and must not be "corrected" -- so "widen every literal" is its own defect and the
only safe procedure is to read each operand. Same pattern elsewhere in the chain:
ComputeOutputFromRates multiplies by an exact 1.5 then a widened 1.2f two
instructions later, and NormaliseOutputRates holds 1e-4 at BOTH widths.

Live result (VM146, turn1-state.sav, three runs): the game pays 499 interest on a
treasury of 50,000 and 380 on 38,100; the exact decimals pay 500 and 381. Every
divergence in the control build lands on a multiple of 100 and nothing else
diverges at all. Coverage stated as distinct states, not calls: 5 distinct
treasuries, 2 on the boundary -- against the earlier green run's 20 distinct
states, none on a boundary.

BANKRUPTCY_PROTECTION_LIMIT_FACTOR read live: 3.29999995 = (float)3.3. Its file
image is zero because the loader fills it at run time, so lane PL-3 could read the
width and had to assume the value. The assumption was right and is now measured.

Falsified: the difficulty-mods record does not sit inline at ServerPlayer+0x36c;
that field is a heap pointer on all eight players. Recorded as a hypothesis with
the measurement, not as a fact.

Second finding, from the rule-19 control: turn1-state -> turn2 is NOT a
deterministic pair. Three runs gave three post-turn autosaves differing in exactly
four leaves -- one Singularity shadow empire's research pick and the derived
checksum. Two of the three runs carried identical hooks, and the un-instrumented
run was a third value, so this is the game and not the instrument. The
determinism oracle stands for ref-turn2 -> turn3 and does not generalise to its
neighbour; no lane should use this pair as a byte-match oracle.
2026-09-08 17:49:35 -04:00

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{
"entries": [
{
"name": "ServerPlayer_off_Aidf",
"offset": "0x368",
"convention": "offset",
"status": "verified",
"prototype": "int aidf -- the difficulty level (0..2) stored by ServerPlayer::Read 0x008804d0 at 0x00880fa3, the selector LoadDifficultyRow 0x005a3990 uses to pick the row it copies for this player. VERIFIED LIVE on VM146: read at ComputeBudget entry on every one of the 8 players of turn1-state across 3,895 calls, it is 1 on all eight, which is the difficulty level the whole corpus carries and the level whose AI column holds the 1.1x income modifier",
"source": "lane L5 live read on VM146 2026-09-08 (shim compare run l5A-widened, 3,895 ComputeBudget records)"
},
{
"name": "ServerPlayer_off_DiffModsPtr",
"offset": "0x36c",
"convention": "offset",
"status": "hypothesis",
"prototype": "DifficultyMods* -- a POINTER to the per-player difficulty record, NOT the record inline. This entry exists to correct a lane L5 mistake and to save the next lane the run. addresses.json already records DifficultyMods_Select 0x0059b490 being called as Select(p->diffMods /*+0x36c*/, p), and lane L5 read the 0x1c bytes AT +0x36c expecting {int id; float ai[3]; float other[3]}. They are not that: the first dword is 0x0da0ec20..0x0da13360 on the eight players of turn1-state -- eight distinct heap addresses within 18 KB of each other and of the ServerPlayer allocations themselves (the player object was at 0x0da08600) -- and the floats behind it decode as denormal garbage (1.7e-38, 1.4e-43). So the field is a pointer and the record is one dereference further on. HYPOTHESIS, not verified: this run did not follow the pointer, so it is consistent with +0x36c being a pointer to the DifficultyMods record and equally consistent with its being some other per-player sub-object pointer. What IS established is the thing the reading was for: the difficulty row is reachable from a ServerPlayer, so compute_budget.h's old coverage note ('not reachable from a ServerPlayer, so the two relevant entries are fitted constants') is wrong as written. The fitted pair {3.0, 1.5} / {1.0, 1.0} remains UNVERIFIED against the running game; the next run should dereference this field behind a readability guard and compare the selected triple against those constants",
"source": "lane L5 live read on VM146 2026-09-08; the prediction that the record sits inline at +0x36c was FALSIFIED by the run (docs/L5-live-verification.md E3-c)"
},
{
"name": "g_ResearchYieldFactor",
"addr": "0x00a2d818",
"convention": "data",
"status": "verified",
"prototype": "double 0x3FEB333340000000 = 0.85000002384185791 = (double)0.85f -- the research-yield factor, multiplied in by ComputeBudget at 0x00863601 as a QWORD operand. THE WIDTH IS THE FINDING, and what makes it a rule-23 case rather than a curiosity is its two NEIGHBOURS in the same product: 1.15 at 0x00a1a4b8 and 0.5 at 0x009e20a0 are stored as EXACT doubles, while this one is a widened float. Three literals, one expression, two widths -- so a C++ port that writes all three as decimals is wrong in exactly one place. The exact-decimal product (money/50 x 1.15 x 0.5 x 0.85) is integral when researchMoney is a multiple of 40,000, and the image's larger constant lands one ABOVE it there: at 40,000 the game gives 391 research points and the decimal gives 390. NOT VISIBLE ON THE CORPUS, and that is now measured rather than argued: the live compare run presented 9 distinct researchMoney values across 3,895 calls and NONE of them is a multiple of 40,000. Read live out of the running process as well, so nothing patched or relocated it",
"source": "lane L5 operand-width sweep of the money chain 2026-09-08, plus the live read on VM146 (inputs.live_consts.researchYieldFactor == 0.8500000238418579 on all 3,895 records)"
}
]
}