Drew T
a741d2b6b5
- RESEARCH (T0-T7): read gcc-2.7.2 source (gcc-papermario) + mined Xenogears (our exact compiler) -> per-class byte-gated verdicts. VERDICT REVERSAL (Drew "hand-match everything"): the call-crossing register-ORDER class is STEERABLE via `register __asm__` pins + a scheduling barrier (func_8012B8E4, the flagship "unsteerable" fn, byte-gated) -- not unsteerable. - TOOLKIT (cookbook §17): pins+barrier (register swap), array-decay (hoist-vs-remat), for-loop/statement-order (structural), sig_unify-mandatory; narrow-param = honest stub. §16 reconciled (§10-vs-§16). - TAUGHT TO WAVES (§17a): calibration 9/16=56% whole-binary (vs 33%); Step-1 (embedded canonical callee sigs + call-site-cast/re-validate) 28/31=90% match_one, 22 verified. ~31 reach-134 matches banked, each propagated x134. fleet 55.51 -> 56.64% (+1.13%). - FINDING: the match_one->gate gap is declaration plumbing (call-site casts not redeclaration; stale M2C_UNK sibling-decl reconcile; implicit-int caller class) -- recovered deterministically. - NEW residual classes: per-file -O0 (~18 fns, needs an -O0 split file like src/boot.c -> high ROI) + gcc loop-guard operand-order (irreducible). W1: build-divergence ruled out by proxy. - make check-all 136/136 byte-identical (R22); dedup 1450 validated/0 failed; 0 NON_MATCHING (G4). - worklog -> phase-ends/logs/Phase18.md (R19); bumps 1.16.0 -> 1.17.0
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
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.