Author Topic: Maximum Over Drive System - Lua Assembly Toolkit (Read 12213 times)

NecroBumpist · « **on:** August 19, 2011, 07:58:46 pm »

Welp, I am in need of more posts before I can join the IRC apparently, so I will introduce you all to a project I'm working on

Since Lua is currently the fastest programming language for up-to-date NSpire calculators, I thought I would share this relevant project.
This really is for those who want to get the absolute most out of Lua. It's very impractical to write an entire program from Lua assembly, since the compiler does a decent job for most non-time-critical functions.

Lua is actually a semi-compiled language (at least that's what I'm going to call it).
It is compiled to bytecode, and than interpreted dynamically on a virtual machine.

You can execute Lua bytecode directly in Lua with the loadstring() function.

Code: (Example 1) [Select]

loadstring("\27\76\117\97\81\0\1\4\4\4\8\0\56\0\0\0\64\67\58\47\85\115\101\114\115\47\74\97\115\111\110\47\68\111\99\117\109\101\110\116\115\47\80\114\111\103\114\97\109\109\105\110\103\47\76\117\97\47\77\79\68\83\47\116\101\115\116\46\108\117\97\0\13\0\0\0\13\0\0\0\0\0\0\2\1\0\0\0\30\0\128\0\0\0\0\0\0\0\0\0\1\0\0\0\13\0\0\0\0\0\0\0\0\0\0\0")();

Now I'd go over the bytecode format, but you can learn all of that here
This document also includes all of the information on all of the instructions to the Lua VM.

Now, onto the project.
(In retrospect, the name I chose was rather silly, but meh, it applies)

Basically, it includes the following:

An assembler for a custom syntax of my own design (feature ridden)
Something I would call a Linker, that takes a table of all the relevant information, and compiles it into Lua bytecode
Soon to be a disassembler, which will turn a normal Lua function into Lua assembly.

You can find the repository here: https://github.com/NecroBumpist/MODS

So, time for "Hello World!" in Lua assembly

Code: [Select]

local mods = require("MODS.Current.main"); 
local bytecode = mods.Assemble(
[[
; Hello_World.lasm
.options 0, 0, 0, 2        ; a directive, which sets some properties, the '2' meaning MaxStackSize

getglobal    0,    <'print'>        ; <> denotes a constant, i've yet to bother with a directive for doing constants
loadk        1,    <'Hello World!'> ; The LuaVM is register based, we put the function in one register, then arguments above it
call         0,    2,    1          ; now we call register 0, with (2-1) parameters, accepting (1-1) values back
return       0,    0                ; and now we return
]]);

loadstring(bytecode)() -- turns the bytecode into a function, then we call that function

>Hello World!

So, I'd like to hear what some of you Lua users who are looking for speed improvements think

I plan on updating the repository soon to include:

Write some proper documentation
Updates to the assembler to include NASM like Macros (debugging right now)

In ten or twenty minutes the repository should be much cleaner

Comments, questions, or concerns ? Or Lua Assembly general thread.

XVicarious · « **Reply #1 on:** August 19, 2011, 09:44:01 pm »

Wow. That looks pretty cool, I know no Lua at all though but still

DJ Omnimaga · « **Reply #2 on:** August 19, 2011, 10:48:41 pm »

Hmm Interesting. I unfortunately no longer am into programming but I'M glad to see more programming tools coming out. For which platforms will this be?

Juju · « **Reply #3 on:** August 19, 2011, 11:26:00 pm »

Looks real nice. So that means another programming language for the NSpire? (And maybe anything that runs Lua?) Cool.

pianoman · « **Reply #4 on:** August 19, 2011, 11:31:09 pm »

Wow, looks pretty nice

Can't wait for it to be finished

NecroBumpist · « **Reply #5 on:** August 20, 2011, 12:38:32 am »

Quote from: DJ_O on August 19, 2011, 10:48:41 pm

Hmm Interesting. I unfortunately no longer am into programming but I'M glad to see more programming tools coming out. For which platforms will this be?

I've yet to run the assembler/linker on calc (the code is horendous (no planning), and it would be really slow for large files.

But I'm mainly posting it because you can utilize whatever code you assemble on any platform that runs Lua.
So basically the NSpire series

Quote from: Juju on August 19, 2011, 11:26:00 pm

Looks real nice. So that means another programming language for the NSpire? (And maybe anything that runs Lua?) Cool.

I'm not sure I would call it an entire new language, since the code it produces is ran normally in Lua. It's just a more minimalistic version of Lua.
So if you do your planning, you could definetly organize your code in way that would be better than the standard Lua compiler.
How much better, I do not know.

It's similar to the coding in C vs. ASM for x86. The best C compilers are better than average ASM coders.
But then again, the Lua compiler really does no optimzations at all. Writing important functions in Lua ASM might be of benefit, but writing simple or non-time-critical functions would likely be a waste of time.

I plan to do an example with a SHA256 algorithm tomorrow, one in normal Lua, another specifically in Lua ASM.
(I'm going to use an external library, so it won't run on calc, but it will show how Lua ASM can be helpful)

DJ Omnimaga · « **Reply #6 on:** August 20, 2011, 02:08:39 am »

Ah ok thanks for the info.

Jim Bauwens · « **Reply #7 on:** August 20, 2011, 05:20:24 am »

Very interesting!
I have yet to try if it actually works on the nspire, but if it does,that would be wonderfull

I've got lots of routines that could use a speed boost

Thanks for your work

pianoman · « **Reply #8 on:** August 20, 2011, 07:55:21 pm »

How exactly would we include this stuff in the actual script, though?

NecroBumpist · « **Reply #9 on:** August 20, 2011, 08:16:21 pm »

Update to v2.2
Now includes NASM like macros:

Code: (Example LASM) [Select]

.options 0, 0, 0, 200 ; yay for large stacks!

.macro print(s, msg){
    getglobal   s,  <'print'>
    loadk       s + 1,  msg
    call        s,  2,  1
}

print   0, <"Omnimaga :)">      ; this line will be replaced with everything in the print macro (this is good for inlining functions and stuff)
return  0,  0

>Omnimaga :)

It took forever to get this shit working, mainly because of my terrible code layout

Anyway, v2.3 will include cool stuff like automatically tracking the top of the stack so you don't have to use .options in every prototype, and LOTS of linker stage checks. This will prevent (well, help you figure out) the common "invalid bytecode" warnings loadstring() returns if you try to load bad code.

More can be read in the README in the repository.

Quote from: pianoman on August 20, 2011, 07:55:21 pm

How exactly would we include this stuff in the actual script, though?

You'd use the loadstring() function to convert the code Assemble() returns into a proper Lua function, which you can easily call and pass arguments to from your normal scripts.

Code: (Use this code to generate bytecode) [Select]

local mods = require("current");
local code = mods.Assemble([[
; put cool Lua ASM code here
]]);

print(code:gsub(".", function(a) return "\\" .. a:byte() end)) -- turn the code into an escape sequence

Code: (Use this code in your production code, or what you put on the calc) [Select]

local code = "" -- copy and paste the output of the previous script here
local func = loadstring(code);
func()

Adriweb · « **Reply #10 on:** August 21, 2011, 07:29:57 am »

Really nice indeed.

Looking forward to be able to test that project in more complex situations, once I understand how to program in this asm-looking language

NecroBumpist · « **Reply #11 on:** August 21, 2011, 10:41:59 am »

Quote from: adriweb on August 21, 2011, 07:29:57 am

Really nice indeed.

Looking forward to be able to test that project in more complex situations, once I understand how to program in this asm-looking language

Thanks

I definetely do more basic documentation on the features of the assembler.

After that, I've included a copy of ANoFrillsIntroToLua51VMInstructions.pdf in the \docs\ folder(the de facto document for learning Lua bytecode, and ultimately Lua assembly)
So that should be a great reference to all those who want to learn the specifics of a particular instruction.

I'll get to work on explaining how to use everything now

Levak · « **Reply #12 on:** August 21, 2011, 11:49:02 am »

Err,
Either I'm stupid (and this is not impossible), or I don't understand how you can excecute this function in the Lua TI-Nspire API :

Code: [Select]

require("MODS.Current.main");

NecroBumpist · « **Reply #13 on:** August 21, 2011, 11:56:46 am »

Yes, that wouldn't run, TI removed file interactions. The examples are really meant to be ran on a desktop.

I would not advocate using this on your calculator (as I've said before, it's slow),
but I'll steal ocLua's concept so you can, just for fun

Edit: in the \bin\ directory there is now a "ocLASM.tns" file. It works exactly like ocLua (many many thanks to ExtendeD

)
Though I still don't recommend actually typing LASM on an NSpire, as it is really tedious.

ExtendeD · « **Reply #14 on:** August 22, 2011, 10:36:51 am »

Interesting project

I'd love to see how TI-Nspire programs will benefit from it.

Author Topic: Maximum Over Drive System - Lua Assembly Toolkit (Read 12213 times)

NecroBumpist

Maximum Over Drive System - Lua Assembly Toolkit

XVicarious

Re: Maximum Over Drive System - Lua Assembly Toolkit

DJ Omnimaga

Re: Maximum Over Drive System - Lua Assembly Toolkit

Juju

Re: Maximum Over Drive System - Lua Assembly Toolkit

pianoman

Re: Maximum Over Drive System - Lua Assembly Toolkit

NecroBumpist

Re: Maximum Over Drive System - Lua Assembly Toolkit

DJ Omnimaga

Re: Maximum Over Drive System - Lua Assembly Toolkit

Jim Bauwens

Re: Maximum Over Drive System - Lua Assembly Toolkit

pianoman

Re: Maximum Over Drive System - Lua Assembly Toolkit

NecroBumpist

Re: Maximum Over Drive System - Lua Assembly Toolkit

Adriweb

Re: Maximum Over Drive System - Lua Assembly Toolkit

NecroBumpist

Re: Maximum Over Drive System - Lua Assembly Toolkit

Levak

Re: Maximum Over Drive System - Lua Assembly Toolkit

NecroBumpist

Re: Maximum Over Drive System - Lua Assembly Toolkit

ExtendeD

Re: Maximum Over Drive System - Lua Assembly Toolkit