Drew T
e2f64a7c62
MY HYPOTHESIS WAS WRONG AND THE AGENT SAID SO. I predicted the ownership oracle was blind to verbatim-asm owners. It is not. 0x800cedf8 is the §154-A LEADING RODATA ISLAND (the module-id header + jtbl/ptr table at segment offset 0), which rodata_carves already exempts via 'off == 0 and sub == ov'. The S68 first carve legitimately renamed that subseg to md_MAIN_003_jr_800D12D0 (§371: spimdisasm rodata migration is same-subseg-only), so the 'sub == ov' conjunct stopped firing and offset 0 leaked in as a 'carve'. The island has NO single owner BY DESIGN -- which is why the exemption exists -- so widening owner kinds could never have restored 1:1. The fix drops one conjunct: offset 0 alone is the honest structural key, because a carve is a table LIFTED OUT OF THE DATA TAIL and can never sit at the segment's own offset 0. Verified across all 213 configs: every offset-0 .rodata piece is an md_* leading island; ov_*/main have none. The R32 hard abort is UNTOUCHED -- this widens the recognised-island set, it does not soften the refusal. NEGATIVE CONTROL (R39) over all 184 binaries with .rodata pieces: OK 182 -> 183, ABORT 2 -> 1, and exactly ONE verdict moved (md_MAIN_003). The remaining us.exe abort (UNOWNED 0x80073238, the LZSS jtbl carve whose owner LzssDecodeSector does not live under src/us.exe/*.c) is byte-identical before and after -- PRE-EXISTING, not newly hidden, and logged rather than silently absorbed. Carve byte-neutral and bank byte-identical, both re-verified by my own rebuild: sha1 dd1b32ecf1103c6f7cf1943d25546a3046e17b14 == config/check.md_MAIN_003.sha. md_MAIN_003 12 -> 11 stubs. THREE o0_subsplit GAPS surfaced and hand-finished, and they must be fixed before the remaining 7 -O0 stubs here are carved: build_new_config drops a cut at the object start so region 0 kept the -O2 name while the tool PRINTED the _o0 name; parse_overlay_c folds pre-anchor text into the FOLLOWING anchor, so a verbatim body inside region 0 attached to region 1; and the island .rodata piece needs repointing to whichever TU ends up holding its emitters.
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.