TheAnsarya/Nexen v1.4.25

Nexen v1.4.25

on GitHub

Fixed

• Linux/macOS build failure - std::chrono::clock_cast is a C++23 feature unavailable in clang + libstdc++ on Ubuntu 22.04 / macOS 14; all Linux (clang, gcc, AoT, AppImage) and macOS builds were failing; replaced with portable time_point_cast arithmetic in SaveStateManager.cpp. (#1219)
• clang [[nodiscard]] placement error in LynxMemoryManager - [[nodiscard]] placed after __forceinline was parsed by clang as an attribute on the return type rather than on the function, causing all Linux/clang CI jobs to fail with 'nodiscard' attribute cannot be applied to types; moved [[nodiscard]] before __forceinline. (#1220)
• Accuracy test CI always failing - accuracy-tests.yml builds the full Nexen.sln including UI.csproj which references Pansy.Core; the pansy repo was never cloned in CI causing CS0246 on every run; added pansy checkout to both smoke-tests and accuracy-tests jobs. (#1219)
• C++ tests CI missing pansy checkout - Same pansy reference issue affected tests.yml; added checkout there as well. (#1219)
• Accuracy tests running on every push - Removed push/pull_request triggers from accuracy-tests.yml; workflow now only runs on workflow_dispatch and the nightly schedule. (#1219)
• Avalonia 12 menu icon loading crash - ImageUtilities threw an unhandled ArgumentException on Avalonia 12 when SVG assets failed to decode; hardened the icon load path with SVG -> PNG fallback and a non-throwing empty-image fallback to prevent UI-thread crashes. (#1212)
• ReactiveUI Avalonia runtime initialization - Startup crash regression introduced when UseReactiveUI() was removed during Avalonia 12 migration; restored correct ReactiveUI.Avalonia runtime initialization. (#1205)
• Avalonia SVG image loading pipeline - Avalonia 12 changed the SVG loading API; replaced the old load path with the Svg.Controls.Skia.Avalonia pipeline so SVG assets render correctly without PNG fallback masking. (#1214)

Performance

• CDL recording page cache - ~75-80% CDL overhead reduction - Eliminated all virtual calls from the RecordRead hot path. Every memory read previously triggered 2 virtual calls + a switch per read (~10-15 ns x 3-4M reads/sec). Replaced with a flat 4 KB page cache mapping CPU-space addresses directly to absolute ROM offsets; RebuildPageCache keeps the cache coherent for consoles with dynamic mapping. (#1207)
• Avalonia rendering pipeline lock reduction - Consolidated DrawOperation bitmap locks from 3 to 2 per frame; lowered DispatcherPriority from MaxValue to Render. (#1207)
• SNES memory handler devirtualization - Every SNES CPU memory access (~3.58M/sec) went through virtual dispatch; for the common case (RamHandler/RomHandler) this resolved to a trivial array access. Added direct-access pointer fields (_directReadPtr, _directWritePtr, _directMask) to IMemoryHandler so SnesMemoryManager bypasses virtual dispatch with an inline array access for the dominant code paths. (#1208)
• NES VS Dual per-frame 240 KB allocation eliminated - NesPpu::SendFrameVsDualSystem() was allocating 240 KB on every frame; moved to lazy member allocation. (#1208)
• NES internal RAM fast path - NES CPU reads to internal RAM (~30% of all CPU reads) now bypass virtual dispatch; combined with the mapper fast path, ~90% of all NES CPU memory accesses are devirtualized. (#1209)
• Atari 2600 std::function elimination - Replaced std::function read/write bus callbacks with a direct Atari2600Bus* pointer, eliminating type-erasure overhead on every CPU memory access. (#1209)
• Multi-system memory dispatch optimization - Targeted SMS, Game Boy, PCE, Genesis, and Lynx with cached CheatManager* pointers, [[likely]]/[[unlikely]] branch annotations, and a Lynx fast-path/slow-path split (inline header fast path for direct RAM, .cpp slow path for overlay dispatch). (#1211)
• ChannelF callback removal - Finalized removal of callback-based dispatch in the ChannelF CPU/memory-manager path. (#1215)
• WonderSwan flash dirty-state caching - Added dirty-flag caching to the WonderSwan flash save-state path to avoid unnecessary I/O on unmodified flash banks. (#1215)
• GBA/NES hotpath benchmarks - branch hints discarded - Real emulator-path microbenchmarks for GBA ProcessDma, ProcessInternalCycle (0%/5%/50% pending-update distributions), and NES BaseMapper::ReadVram; measured and discarded [[likely]]/[[unlikely]] annotations that caused a +14.7% regression. (#1217, #1218)
• Repeatable benchmark script - Added ~scripts/run-memory-hotpath-benchmarks.ps1 for consistent hotpath perf audits with labeled, timestamped JSON output. (#1218)

Downloads

Windows

Linux

macOS (Apple Silicon)

Notes:

• Linux requires SDL2 (sudo apt install libsdl2-2.0-0)
• macOS: Right-click -> Open on first launch to bypass Gatekeeper