ARMSX2/REFACTOR_STATUS.md

ARMSX2 monorepo refactor — status & roadmap

Goal: one shared PCSX2 core (arm64 JIT) at the repository root, with the Android and iOS frontends as thin subfolders that consume it, and CI that builds every target on every commit.

Branch: refactor/monorepo (off macOS). Nothing on the remote has been changed yet.

Decisions (locked)

Topic	Decision
Canonical core	macOS branch (127 unique arm64-JIT commits, newest). Becomes main.
Core strategy	Single shared core. Mobile core forks collapsed; vendored copies deleted.
Mobile history	Snapshot (squash) into subfolders; full history stays on the archived branches.
Layout	platforms/android/, platforms/ios/.
Old branches	macOS → default main; master → master-archive (non-destructive); other branches left as-is.
Build wiring	Rewire mobile builds onto the root core immediately; delete vendored copies.

Branch reality (measured)

• master: old upstream PCSX2, 22,653 commits behind macOS → archive.
• refresh-experimental (Android): full core fork at root + a 2nd vendored core under ARMSX2/app/src/main/cpp + a 2nd vendored 3rdparty.
• iOS-refresh: React-Native shell with a full vendored core under app/src/main/cpp (12,782 files, 93% of the branch).
• Android arm64 JIT: only 7 unique commits (3 real fixes) vs macOS's 127. The arm64/mac/* IR-VU backend + split aVU0/aDMAC/aVTLB/aR5900COP* are a superseded experiment macOS already consolidated past → dropped.

Done

• platforms/android/ — Android app snapshotted; vendored core deleted; 24 Android-only core additions relocated into the root core behind if(ANDROID); on-device arm64 test harnesses preserved; thin CMake sources the root core. (commit: "move Android frontend …")
• platforms/ios/ — iOS app snapshotted; vendored core + vendored 3rdparty deleted; iOS-only additions relocated behind ARMSX2_IOS; NEON SPU2 shared by both arm64 mobile targets; cruft dropped; CMake rewired to root core via ARMSX2_ROOT, iOS-SDK/bundle/entitlement config preserved. (commit: "move iOS frontend …")
• .github/workflows/build-all.yml — one push builds PC macOS-arm64, PC Linux-arm64, Android APK, iOS .app; each uploads its own artifact.

Remaining (the long pole — needs real toolchains / CI iteration)

1. Compile-green each platform. None of the collapsed-core builds has been compiled yet (this was done in a shell without NDK/Xcode/mac-Qt). The build-all.yml Android + iOS jobs are continue-on-error: true on purpose — they are the mechanism to surface and fix the remaining issues. Flip to blocking once green.
2. Shared-file reconciliation (~250 files). The Android core fork also modified shared files (FullscreenUI, Achievements, GS device backends, VMManager, MemoryCardFile). Those deltas are not yet merged — only the net-new Android/iOS files were relocated. Diff each against the root core and fold in the genuinely mobile-specific changes behind platform guards; discard stale-upstream noise. Source of truth for the deltas: git diff macOS refresh-experimental -- pcsx2 common.
3. arm64 JIT fixes to port (3 real Android commits): 45b4b68d10 (microVU PQ lanes), 75351e8545 (FTOI NaN / SQRT clamp), ec06302ccf (skip microVU emit on jump-cache hits).
4. 3rdparty de-duplication. platforms/android/.../cpp/3rdparty (adrenotools
   • others) is still vendored for the NDK build. Keep adrenotools/oboe (Android-only); evaluate sourcing the rest from root 3rdparty/ once the NDK build is green.
5. common/PNGStub.cpp (iOS) is relocated but not yet wired into common/CMakeLists.txt — add under an iOS guard if the iOS build references it.
6. Windows-on-arm64 PC build: no reusable windows_build_qt.yml exists on this branch. Add one and a pc-windows-arm64 job in build-all.yml.
7. Finalize remote (destructive — confirm before pushing):
   • Promote macOS/this branch to the default main.
   • Rename master → master-archive on the remote.
   • Leave the other stale branches untouched.