With [timing] guest_cycle_scale active, every one-cycle psx_cyc_charge went
straight to psx_cpu_charge and psx_advance_cycles, bypassing the batch the
scale-1 path uses. [timing] guest_cycle_scale_batch (PSX_GCS_BATCH=0/1)
scales the charge in place, with the same fractional carry and order as
psx_cpu_charge, then batches it like the scale-1 path. It flushes at the same
observation points. Default off.
R4 exactness, frame_fingerprint off vs on, 9000 frames each: headless boot
through intro, title and attract; a 1P Grand Prix race; and a 2P VS race.
cyc, mmio, mc and qc are identical on every frame. sp, wr, pc and ws are
identical at the end. The only differences are single-frame VBlank straddles
of wc/sc (never two frames in a row). 0 dispatch misses.
Speed, release builds, races at 60 Hz:
- M4 (macOS sample): psx_cpu_charge 4.3 % -> 0 % of emulation-thread samples;
busy 46.0 -> 44.4 % (2 pairs).
- 9800X3D: no measurable change (30.0 vs 30.5 %; one core 44.6 vs 44.2 %).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Review of #561. Guest time now has two entry points (psx_cycles.h): the
CPU charge psx_cpu_charge() (instruction base, load fudge/region/completion,
i-cache refills, BIOS HLE costs), which applies [timing] guest_cycle_scale,
and the unscaled device advance psx_advance_cycles() (DMA, idle skips,
mul/div and GTE deadline waits). The emitters' block-mode charges emit
psx_cpu_charge; overlay DLLs accumulate it raw and publish through the
cpu_charge callback (was advance_cycles, same slot) into the same host
function, so nothing is scaled at the DLL boundary. The batched
psx_cyc_charge path, the dirty-RAM interpreter, psx_cyc_readmem, i-cache
refills and bios_hle.c all charge through it. At scale 1 it is exactly
psx_advance_cycles.
Gate in psxrecomp: [timing] guest_cycle_scale_gate, RAM predicates judged
at every VBlank edge (deterministic, works online, no mod needed), plus
psx_mod_set_guest_cycle_scale_gate() in mod_plugins.h for custom logic or
to tie the scale to a mod (guest_cycle_scale_gated = true; every mod
session reset shuts it). The carried fraction and both gate states are a
boot_state section (BS_SEC_GCS, written only when the scale is not 1), so
savestates and the netplay rollback snapshot re-simulate the same cycles.
psx_guest_cycle_scale_gate_test pins tier identity, the gates and rollback
re-simulation against the real psx_cycles.c.
OpenBIOS regenerated (emitter stamp); retail SCPH1001 is not.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
No CPU is emulated: recompiled code charges the guest clock a fixed cost
per instruction. guest_cycle_scale = N charges 1/N of it (instruction,
load, mul/div, GTE latencies, overlay DLL batches) while VBlank, timers,
CD, SPU and DMA keep hardware time, so the game never runs out of frame
time. A title constant in game.toml (1 = faithful, 1..64), never a player
setting; guest_cycle_scale_gated applies it only while the title's mod
opens the gate (psx_guest_cycle_scale_gate_open). PSX_GUEST_CYCLE_SCALE
overrides for testing. A scale other than 1 is folded into the netplay
content fingerprint as a safety net.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The UI prepass re-read aperture node payloads through the RAM-folded key, so
THPS2's relocated prim arena discarded the HUD squash every frame.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Fixes Ape Escape terrain seams: CPU-built subdivision midpoints and lwl/lwr-copied
grid corners drew native next to precise neighbours. Adds pgxp_tri_ring/pgxp_store_ring.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Mouse policy now folds onto the resolved pad (source included) instead of a discarded capture; no-policy path does no mouse polling.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Matthew Stanley