Files
psxrecomp/runtime/include
Matthew Stanley 582aeccdac bios: HLE as a first-class swappable tier (gbarecomp model) + HLE boot shell-skip
USER PIVOT 2026-07-02 (CLAUDE.md §0 amendment included): psxrecomp now
carries an opt-in High-Level Emulation backend alongside LLE. LLE (the
recompiled BIOS) stays the default, the reference implementation, and the
correctness/timing oracle; every service HLE does not implement falls
through to LLE, so HLE is never load-bearing beyond what it covers.

Mechanism: full_function_emitter.cpp emits a null-by-default hook
g_psx_bios_hle_hook consulted at the top of every psx_dispatch_impl
iteration, on the pre-normalize physical address, BEFORE any backend
(game image / dirty-RAM / static table) claims the target. A handled
call resumes at $ra through the trampoline's existing return/tail
contract. NULL (default) = pure LLE, dispatch-identical. Regenerating
BIOS+game images is required (emitter change).

v1 call-HLE (runtime/src/bios_hle.c): the B0 event family — DeliverEvent
(incl. callback dispatch with the kernel-true $ra 0x1720), OpenEvent,
CloseEvent, TestEvent, EnableEvent, DisableEvent — each ground-truthed
instruction-by-instruction against the SCPH1001 kernel disassembly
(0xBFC11644..0xBFC11A84) and operating on the REAL guest EvCB table
([0x120]/[0x124], stride 0x1C). WaitEvent/threads/pads/card/A0/C0 fall
through to LLE. Cycle charges are documented approximations; LLE remains
the timing oracle. No-stubs stands.

Boot HLE: with the tier on (and no keep-intro opt-out) the hook one-shot
intercepts the first dispatch of the BIOS shell entry (RAM 0x30000 —
LoadRunShell's indirect call always routes through the dispatcher), so
BIOS Main() proceeds straight to SYSTEM.CNF + game EXE load with kernel
state built entirely by the real recompiled kernel init, unpaced (boot
turbo) until game handoff. This REPLACES the fast_boot snapshot
capture/restore; fast_boot=true now aliases the boot-skip alone.

Selection: [runtime] bios_hle / bios_hle_keep_intro (+ settings.toml
bios_hle mirror), PSX_BIOS_HLE / PSX_BIOS_HLE_KEEP_INTRO env overrides,
startup banner bios_backend=/bios_boot=. The PSX_HLE_SCHEDULER spike is
folded in as the tier's standing subsystem replacement: default from
[runtime] hle_scheduler via psx_hle_scheduler_set_default, env wins.

Observability: always-on 16K-entry HLE ring (route LLE-fallthrough /
HLE / boot-skip per record) + hle_dump TCP command (TCP_COMMANDS.md).

VALIDATED on Tomba (build-wt): LLE pass byte-identical behavior (real
intro, card check, save/load OK); HLE pass boots shell-less, TestEvent/
DeliverEvent route HLE, ChangeTh/ReturnFromException/OpenTh/CloseTh and
the card stack fall through to LLE, save/load OK (user-driven).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-07-02 16:27:33 -07:00
..
2026-05-17 21:58:55 -07:00