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Finished optimizing the main drawing functions for uxn-playdate getting speedups ranging from 1.98x to 4.38x.

Only screen_fill missing and then it's time to do audio and filesystem stuff. At this point the playdate should be able to handle pretty much any rom you throw at it (within reason). I think there is full speed parity for Oquonie compared with uxnemu.

More testing is needed of course, and I could make things faster but not worth it until I can test on hardware. :uxn:

#uxn #playdate

#uxn #playdate
in reply to Bad Diode

Devine Lu Linvega
Devine Lu Linvega
• •

that's sick! I was looking at the uxn core, and I think it could be to run faster.

Many times you increment the stack pointer each push and pop, I was wondering if it'd be faster to move it once, and write the values with an offset, so something like PUSH(a) PUSH(b) wouldn't load the ptr twice, just once and write a at -1 and b at -2.

in reply to Devine Lu Linvega

Bad Diode
Bad Diode
• •
@neauoire it's best not to do these optimizations manually, the compiler should be able to do this for you. There may be some operations where this could help, but if you decide you wanna give it a try let me know and I can A-B the changes 😀
@Devine Lu Linvega
in reply to Bad Diode

Devine Lu Linvega
Devine Lu Linvega
• •
oki 😀 yeah I never know what turns into what, with one of the older cores, I noticed that in Compiler Explorer it would do an extra load between each.
Unknown parent

Devine Lu Linvega
Devine Lu Linvega
• •
@sigrid yeah, I don't really know how to look at generated arm code, I only have compiler explorer right now.
@Sigrid Solveig Haflínudóttir
in reply to Devine Lu Linvega

Bad Diode
Bad Diode
• •

@neauoire @sigrid you can do that on compiler explorer, just need to target the right CPU:

https://godbolt.org/z/8G35d8TKG

Or offline with:

arm-none-eabi-objdump -d build/pdex.elf


Compiler Explorer - C++ (ARM GCC 8.2.0)

/* Copyright (c) 2021 Bad Diode Permission to use, copy, modify, and distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.
godbolt.org
@Devine Lu Linvega @Sigrid Solveig Haflínudóttir
in reply to Sigrid Solveig Haflínudóttir

Devine Lu Linvega
Devine Lu Linvega
• •

@sigrid aaah, that's cool I didn't know you could change target like that with godbolt.

Wouldn't that just give me x86 if I'm on the thinkpad?

@Sigrid Solveig Haflínudóttir
Unknown parent

Devine Lu Linvega
Devine Lu Linvega
• •
@sigrid ah okok, thanks
@Sigrid Solveig Haflínudóttir
in reply to Bad Diode

Bad Diode
Bad Diode
• •
Lol the screen filling function was very slow and Oquonie uses it a lot. Improved the performance 4.64x times over the already good performance. Yeah, @neauoire you are not going to have trouble running this lol.
@Devine Lu Linvega
in reply to Bad Diode

Devine Lu Linvega
Devine Lu Linvega
• •
HOW?! what the hell, it was such a simple routine too?! The more time I spend inside computers the less I understand how they work
in reply to Devine Lu Linvega

Bad Diode
Bad Diode
• •

@neauoire it was calling ppu_pixel on a double loop, now I write 1 tile at a time, handling the corner cases and such.

Anyway I'm done for now with the optimization work, time to do some more practical stuff, like audio and some extra menu goodies.

The worst (best?) thing is that all this work gave me even more ideas for optimizing uxngba video drawing... hmmmmm

@Devine Lu Linvega
in reply to Devine Lu Linvega

Bad Diode
Bad Diode
• •
@neauoire in fairness I already did a lot of this optimization work when working on the gba routines, just had to port them over (which was a bit tricky at times). Still, I'm no expert, just trying to get a bit better everyday 😀
@Devine Lu Linvega

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