HISTORICAL: releases 12/13, before native move entry.

GNU Chess 6.3.0 / Ensemble 1.x - original 8088/8086 instruction set
22 October 2026; English 6.3.0.12 and German 6.3.0.13

- Lower the native interface and generated lock bridges to 8086 instructions.
  Replace PUSHA/POPA with exact 16-byte register frames without PUSH SP;
  use CS-memory argument pushes, CL-counted shifts and legal long-branch
  sequences. Keep all drawing/cache/input behavior and private-state layout.
- Share bridge entry register-save code. Each target stub is a 7-byte near
  CALL plus inline relocated handle/entry descriptor. Entry state is 24 bytes,
  cleanup 22 bytes. Move saved FLAGS over the near IP, skip the old FLAGS
  before POPF, and enter the engine with its original argument SP/FLAGS.
- Preserve all 119 engine target identities and 272 retargeted call operands
  per language. All other normalized engine instructions/data, runtime,
  artwork/icon payloads and resource loading flags remain unchanged.
- Preserve depth 1-4/default 2, search/evaluation/caches/history/Undo behavior,
  resizable board, shared Berkeley 10-point font, original FreeGEOS icon,
  window title GNU Chess 6.3.0 and icon caption GNU Chess.
- No new data/heap/framebuffer reservation. DGROUP 8400, arena 34336 with 34260
  used after initialization, and stack 49152 are unchanged. Bridge entry
  temporarily uses one extra stack word. Fixed resource reservation falls
 960 bytes English /992 bytes German versus releases 10/11.
- Both editions: fixed initialized resources plus stack 127616 bytes.
  All resources plus stack: EN 214848 bytes / DE 214832 bytes.
  Executables: EN 170028 bytes / DE 170012 bytes. Figures exclude runtime heap,
  handles, loader, shared libraries/fonts and windows; not total physical RAM.
- Current acceptance combines strict raw 8086 opcode/execution semantic
  guards, independent finite decoder oracles, production bridge ABI cases,
  normalized engine/source identity, paint/input/game tests and a dedicated
  DOSBox-X 8086 native core with 640 KiB conventional RAM and disk-only swap.
  XMS, EMS and UMB are disabled. See current report for finite scope/limits.
  This is not physical 8088 testing or a bus/cycle-accurate speed benchmark.

Current evidence: EVIDENCE/cpu8086. Previous 386+ UI 10/11 evidence is retained
at EVIDENCE/ui-history10-11. Older UI 8/9 and slim engine 6/7 graphs/timings
remain historical; no old timing is presented as a new 8088 speed result.
No commercial runtime/font/SDK/compiler executables are redistributed.
