mirror of https://github.com/Druthulu/BFM-decomp synced 2026-09-26 13:33:34 -04:00

Files

T

Drew T de35505a63 feat(phase-19): scale the toolkit — 2 waves (88%/92%), fleet 56.64%->58.00%, propagation is the cap (v1.18.0)

- T1 (prior session, commit:0158/commit:0159): per-file -O0 split infra + 6 -O0 matches; deferred the
  10 %lo-folding-quirk fns + the ×134 rollout (R14 corrected "free ×134")
- T2 (commit:0161): recovery tooling. R14: the 3 Phase-18 "implicit-int" near-misses are NOT
  implicit-int -> resident-callee link-miss (NEW canon_resident_calls.py) + shared-caller arity
  (no-proto caller-extern fix). 3 matches; cookbook §17a-3 corrected
- T3 (commit:0162/commit:0163/commit:0164): 2 Ultracode waves over reach-134 tractable residuals. batch-1
  44/50 match_one (30 banked, 25 propagated ×134); batch-2 35/38 (25 banked, 10 propagated).
  NEW fix_arity_callers.py (no-proto, ALL 18 batch-2 failures were the arity class); canon-first
  2-stage gate (sig_unify REGRESSES canonical drafts); gen_harvest_targets garbled-sig fix
  (0/749, 88%->92%); build_engine_types --strip lift (+4 propagated)
- FINDING: propagation (not matching) caps the fleet-% yield — typedef/local-type bodies can't
  auto-propagate (-> Phase-20 type-lift lever). decomp.dev-comparable byte-weighted est ~30%
- check-all 136/136 BYTE-IDENTICAL (R22); dedup 1450->1485/0 failed; 0 NON_MATCHING (G4);
  fleet 56.64% -> 58.00% (+1.36%). worklog -> phase-ends/logs/Phase19.md (R19)
- bumps 1.17.0 -> 1.18.0

2026-06-20 20:33:00 -06:00

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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 in ov_SC01_077 and propagated ×134 via tools/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.