issn-axy (branch issn-axy, 2026-10-21): shadps4/video_core, shadps4/shader_recompiler, shadps4/common,
shadps4/core/libraries/gnmdriver and shadps4/core/libraries/videoout are axylpup's inFAMOUS Second Son build
of shadPS4 (github.com/axylpup/shadPS4, branch second-son, 2212a345 = release v1.0.2, GPL-2.0-or-later;
shadPS4 0.17, upstream main of 2026-08-08, plus ~750 commits). Its release switches (shadps4-flags.txt)
are the game profile's defaults (scripts/game_profiles.py, AXY_RELEASE_FLAGS); its game code patches are
shim/issn_game_patches.cpp. Port changes on top are marked "issn-axy:" (and "port:" as before):
common/path_util.{h,cpp} and common/ntapi.h are the port's versions (upstream b4e7ae7 + port changes),
the presenter blits the frame and draws the port's menu instead of shadPS4's ImGui layers, screenshots
are off (no libpng), and the Windows-only diagnostics are stubbed on Linux builds. Also vendored:
third_party/streamline-sdk (NVIDIA Streamline headers, MIT) and third_party/stb (stb_image, public domain).
The previous core (upstream b4e7ae7 with the port's own renderer work, FSR 3/4, TAA, ...) is in the
history of branch issn.

Vendored from https://github.com/shadps4-emu/shadPS4 commit b4e7ae776071ceb1dd35004577a8719481e1d258 (GPL-2.0-or-later).
Directories: src/video_core, src/shader_recompiler, src/common, src/core/libraries/{gnmdriver,videoout}, externals/gcn, externals/sirit, externals/half.
Also: src/core/libraries/kernel/{orbis_error,posix_error,time,process,equeue}.h, equeue.cpp, src/core/libraries/error_codes.h, src/core/platform.h, src/core/libraries/system/{userservice,systemservice}.h.
Also: src/core/libraries/avplayer (without the handle streamer), src/core/libraries/videodec/video_utils.{h,cpp}.
Local changes are marked with "port:" comments.
Backported from upstream after b4e7ae7 (2026-10-02), recompiler correctness fixes only:
  233562929 V_INTERP_MOV_F32 P10/P20 selectors (#5087), d96278e1e compute shader floating-point
  mode (#5126), e518a6515 S_SUBB_U32 SCC wrap (#5031), 282e5c792 S_ADDC_U32 SCC carry-out (#5030),
  fb6367d29 32-bit literals in the high dword of 64-bit floats (#5114), 94e217781 V_BFM_B32 (#5185),
  d1cb90dbb ADDC (#5200), dd43d1cac V_CVT_PK_U8_F32 (#5194), ef08b1e1f V_ALIGNBIT/ALIGNBYTE (#5186).

issn (inFAMOUS Second Son port), changes marked "issn:":
  Backported from upstream between b4e7ae7 and 2338a06, unchanged: 612713d5 geometry invocation
  count, 53af37af V_TRUNC_F64, 282f6445 V_MIN_F64, caeb240d Flat VUID-06202, e0cd957a SampleId on
  the KHR barycentric path, 4c7b287f readlanes before tessellation/ring passes, 3f21ee0b
  PackedAncillary lowering. By hand: 1a0f5be8 default sampler for S# with undefined fields.
  From the shadPS4-AYOUB1080p build for inFAMOUS Second Son (github.com/weshayoub92/shadPS4-perf
  153a5aa7, GPL-2.0-or-later), correctness parts only: legacy multiply in V_MAC/V_MAD_LEGACY_F32,
  1D image atomics, WaveMemoryBarrierPass and multi-wave LDS barriers (profile flags),
  FORCE_UNNORMALIZED S# pattern, ISub folding, InverseBallot warning, append buffer lane offset.
  Not taken yet (performance, tied to that build's scheduler): threaded command recording,
  readback queue, async graphics pipelines, real occlusion queries, per-draw memoization, the
  upstream memory tracker and renderer reworks (1eab1796, c6b24ec1, fca10b26) and 8c91be2b,
  f6cd16e8, e754ce62, 2f40f87b, c6fa48c7, c01ae7e6, bcf083f0, 41c0fca5, 4cbd23ef.
