Drew T
0c2b37a287
Found by running one reject to ground. After a gate that REJECTED
resident:func_800D06E8, config/overlays.mk had a 4th JTBL_PADS entry and had
LOST `--pre hdr.rodata.o` (the §440 resident leading-rodata sandwich). The
binary then would not build at all -- "consumed 3 rodata jump table(s) but 4 pad
spec(s) given -- table-count drift vs the carve" -- while src/ was perfectly
clean, which is the only place anyone looks before building.
Root cause is a silent narrowing in the classic shape. harvest_verify snapshots
ONLY the gating binary's own overlays.mk block on purpose (the file is shared by
every parallel gate; a whole-file restore resurrects other binaries' lines --
the S62 defect). But _mk_block_span was SINGULAR: the first `# --- <binary>`
header through the next `# --- `. A binary whose carve state spans more than one
block was half-snapshotted and silently half-restored. It returned a TRUE span
for a scope smaller than the caller believed, and nothing compared the two (R32).
Blast radius measured before costing (R37): 1 of the 142 binaries that have a
block -- resident, which has exactly two (§8e pad spec, §8f leading-rodata
sandwich) and still holds 587 instructions of open stubs.
_mk_block_spans (plural) snapshots a LIST, restores tail-first so earlier spans
stay valid, collapses to the snapshot when the header count changed rather than
leaving half-state, and RE-READS and compares the result -- the defect it
replaces was a reported success. _mk_block returns None (not []) for the 71
binaries with no block, so the caller's guard keeps its meaning.
Negative control, three ways:
* snapshot -> restore is a NO-OP on 142/142 binaries with a block;
* the real S75 damage is fully undone;
* the OLD single-block restore provably does NOT undo it -- the positive
control that proves the fix is load-bearing, not decorative.
Cookbook §444 also records the two other findings from the same reject: the
classified ledger stores the LADDER'S FINAL verdict (the recorded CC1-FAIL came
from a late sig_unify rung; the raw draft compiles and fails on BYTES), and
match_one MATCH + rtu_match MATCH is still not bankable -- func_800D06E8's real
blocker is a jump table (built binary 20 bytes longer, 0x800CEDFC holds a table,
69,571 words shift), because neither matcher LINKS.
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.