cpu_thread option about winuae HOT 2 CLOSED

It is experimental option that never got anywhere. I can try to fix it someday.. And it won't help with compatible modes anywhere where CPU must be slowed down by chipset. Normal (non-CE) modes should not be noticeably slower. (If they are, something is wrong).

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@tonioni Thanks for the clarification. It's expected that in cases where we need CE modes, this won't help, of course. But it might help in other scenarios (e.g. fastest possible CPU emulation/JIT/Non-CE modes).

I'll keep an eye out for any fix in the future then, and leave it for now.

Regarding the performance difference I mentioned, it seems to be in the custom/drawing/blitter combo, not the CPU emulation. The newer code for these (after the recent rewrite to improve accuracy) seems to be slower, at least noticeably so on slower devices.

To give you a concrete example:
Game: Jim Power's title screen,
Hardware: Pi400 (overclocked at 2.2GHz)
Config: Quickstart A1200 (the A500 is less demanding, so I use the A1200 to stress things more)

Using the older (pre-rewrite) code, this runs at full 50 FPS. CPU usage is about 80%
Using the newer rewrite, it maxes out a CPU core at 100% and only manages to hit 40 FPS.

It works fine on a more powerfull RPI5, and x86_64 platforms don't notice the difference either, of course.

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