Drew T
f72e2344a6
Item 1 off T53's list. Two changes: the route, and the design flaw underneath it.
THE DEFECT UNDER THE DEFECT (cookbook §106). residual_class answers two questions in one pass:
`klass` is a MEASUREMENT (expensive, from comparing instruction streams); `(profile, bucket)` is a
POLICY (a table lookup over it). autopsy persisted BOTH and verdicts() read BOTH back — so editing
_ROUTE changed nothing until someone re-ran the whole collect, and a weeks-old row could silently
out-vote the live table with no oracle to report it. The corpus on disk is dated Jul 21 and does not
even contain the SESSION-23 targets the recommendation cited.
Fixed by re-deriving at read time: residual_class.route_for(klass, detail), called from
autopsy.verdicts(). R33 — persist the measurement, derive the decision. Subtlety: LENGTH-DRIFT's
route is MAGNITUDE-dependent (permuter only when |delta|<=2 AND explains=="tail", §60b), so a naive
re-derivation from klass alone would have silently demoted 9 rows; both inputs are already in
`detail`, so the override reproduces exactly — VERIFIED 1610/1610 against the stored corpus with the
table UNCHANGED, before touching it.
THE ROUTE CHANGE: ADDRESSING ("cse","permuter") -> ("cse","structural"). It contradicted this file's
own bucket definition ("structural — local mutation CANNOT introduce it ... it wants a C-level
idiom"): the §10/§20 hoist-vs-remat shape is a multi-instruction change with a documented recipe
(gcc-2.7.2-map/cse_expr.md §2, byte-proven on func_80149374/func_801493D0). Measured (T31): both
admitted ADDRESSING targets plateaued under a §31-directed permuter, and the class was 32% of the
admission pool. After: pool 56 -> 38, exactly 18 rows changed, ALL ADDRESSING, nothing else moved;
grinder admits 45, structural skips 512 -> 530.
THE BOUND (R14), kept in the _ROUTE comment: I read the T31 record instead of the summary line, and
the summary was looser than the evidence. T31 finding 4 byte-tested the §2 recipe on func_80132F40
across six variants and it never closed (best 40 mismatches). `structural` does NOT promise a free
fix — it means "a search over local mutations is the wrong tool, try the documented idiom", exactly
what WIDTH / BRANCH-POLARITY / IMM-OFFSET already mean. Also corrected: the checkpoint cited
func_80176734 as the flat-for-32-min evidence, but that function is not in the corpus at all.
Tooling-only: no src/ or config/ change, no bank, no metric move.
BFM-decomp
A matching decompilation of Brave Fencer Musashi (PlayStation, SLUS-00726, USA 1998) — the first public decompilation effort for this game.
What "matching" means
The goal is C source code that, compiled with the original-era toolchain (PsyQ 4.x / GCC 2.7.2-family + ASPSX via maspsx), produces a byte-for-byte identical SLUS_007.26 and, eventually, byte-identical overlay binaries. SHA1 checksums are the ground truth; "functionally equivalent" does not count.
No ROM content
This repository contains no game assets, no disassembly output, and no ROM-derived data — only source code, build configuration, symbol names/addresses, hashes, and documentation. To build or contribute you must provide your own dump of the game disc (4-track BIN/CUE, redump layout). See .gitignore for the firewall.
Project status
Latest (Phase 19, 2026-06-20): the project builds 136 binaries byte-identical from a clean tree (the EXE + the resident engine + all 134 location overlays);
make check-all→ 136/136. Fleet byte-identical-from-source is 58.0% (function-instance-weighted; see the PhaseEnds for the byte-weighted ~30% figure and what it includes). Shared engine functions are matched once inov_SC01_077and propagated ×134 viatools/dedup_propagate.py. (The narrative below is Phase-11/12-era; a full refresh is part of the public-flip prep.)
Gen1 (foundation) complete — the matching pipeline is proven end-to-end. make extract && make build && make check rebuilds SLUS_007.26 byte-for-byte identical (SHA1 143dbb89…) from C + assembly, reproducibly across many sessions.
- Compiler pinned by evidence:
gcc-2.7.2-psx -O2 -G0 -mips1 -mcpu=3000+maspsx --aspsx-version=2.56 --expand-div. - 52 functions hand-matched to byte-identical machine code — including the LZSS streaming decompressor — with a decomp-permuter + matching-cookbook "flywheel" to accelerate the next.
- 959 PsyQ SDK functions linked byte-identical (libcd, libgs, libgte, libspu/libsnd, libgpu, libc2, libmcrd, libapi/libcard, libetc) straight from the real PsyQ 4.0 libraries instead of re-decompiling them — bringing byte-identical-from-source coverage of the EXE to ~50%.
- File-loader / overlay system reverse-engineered, with the resident engine blob + location overlays' load addresses proven byte-identical against a live PCSX-Redux RAM dump.
About half the EXE is still INCLUDE_ASM stubs (correct bytes, not yet C), and the bulk of the game lives in compressed overlays inside the .CD archives — Gen2 (overlays & engine at scale) is underway:
- The build toolchain is binary-agnostic (one parameterized pipeline builds any binary), and the always-resident engine blob rebuilds byte-for-byte from source (SHA1
8e17e02f…) — the second binary reconstructed exactly, after the EXE — and is now 86% hand-matched C (123 / 146 functions, up from 0): its scripting turned out to be compiled-MIPS state/mode dispatch, not a bytecode VM, and the save-file + sound (SQV) formats are documented. The harvest used a reusable swarm-of-agents + bit-for-bit byte-gate method (a wrong match can't be accepted) —tools/harvest_verify.py+tools/match_one.py, which carry straight into the overlay phase. - A cross-binary deduplication pipeline is live: a Ghidra-free signer fingerprints all 134 location overlays, and the report finds ~9,000 byte-identical function groups shared across binaries (~28 MB of collapsible code) — a single engine function is byte-identical in all 134 overlays. This is "one match unlocks many": each engine match will be auto-credited across the overlay fleet.
Current phase and detailed progress live in phase-ends/ (newest PhaseEnd_*.md = current state); methodology, rules, and the full roadmap are in PROJECT_CONTEXT.md; environment setup in docs/SETUP.md.
This project is developed primarily by Claude Code driving Ghidra through an MCP server; see CLAUDE.md.
License
Private repository for now. AGPL-3.0 is planned at public release, modeled on sotn-decomp. tools/brave-CUE/ is CUE's BRAVE extractor (GPL, source included) and retains its own license.