37 replies to this topic

[Allas]

Well I modified the program and compiled with -Osir but visual speed not change.

This is the ML program version

Quote

        *=$0600
        pla
        ldy #$00
bucle   tya
        sta ($58),y
        iny
        bne bucle
        rts

This is the CC65 version

Quote

#define poke(addr,val)  (*(unsigned char*) (addr) = (val))
#define pokew(addr,val) (*(unsigned*) (addr) = (val))
#define peek(addr)      (*(unsigned char*) (addr))
#define peekw(addr)     (*(unsigned*) (addr))
int main (void)
{
   int n = 0;
   int x = peekw(0x58);

   for(n=0;n<702;++n)   // Print chars in screen
   {
     pokew(x+n,n % 256);
   }

   while(peekw(0xD01F)!=6) {  // Wait key START
   }

   n=0;               // Clear chars in screen
   while(++n<702)
   {
     pokew(x+n,0);
   }

   while(peekw(0xD01F)!=6) {   // Wait key START
   }

}

I use to compile cl65 -t atari -Osir prueba.c -o prueba.xex
There are much difference between ML and CC65 speed. So ML has the advantage that only use one byte counter offset to print chars. After all, I study the ML resulting from CC65 compiler.

 prueba.zip   1.22K   32 downloads
 prueba2.zip   306bytes   36 downloads

P.D. I feel very fine to program in C and it's incredible for me to see after years that CC65 had grown. I'm sure complex logic projects will be developed in right way. Last example, show differences about using WHILE and FOR loops. In any way, commands loops stole much procesing time. But I read more about.

Edited by Allas, Wed Oct 19, 2005 12:32 AM.

[Shawn Jefferson]

Allas, on Tue Oct 18, 2005 10:20 PM, said:

This is the ML program version

That's quite a difference, which illustrates how hand-tuned assembly can be faster. Also, your C program is using double-byte math. It could be written to not use int data types. Still, you will never get the compactness and speed of hand made assembly.

Quote

I'm sure complex logic projects will be developed in right way.

That's really the power of high-level languages. You can build your project quickly and then optimize where its needed (if at all.)

[Wrathchild]

Try this for slightly better generated code, the use of statics
removes the overhead of using the CC65's stack to hold the
variables and hence call functions to maintain them.

#define poke(addr,val)  (*(unsigned char*) (addr) = (val))
#define pokew(addr,val) (*(unsigned*) (addr) = (val))
#define peek(addr)      (*(unsigned char*) (addr))
#define peekw(addr)     (*(unsigned*) (addr))

int main (void)
{
   static unsigned char n = 0;
   static unsigned char *x;

   x = (unsigned char *)peekw(0x58);

   n=0;
   do
   {
     x[n] = n;
   } while (n != 0);

   while(peek(0xD01F)!=6) {  // Wait START
   }

   n=0;
   do
   {
     *(x+n) = 0;
   } while (n != 0);

   while(peek(0xD01F)!=6) {   // Wait START
   }

}

Note too the difference in the loops in the of accessing memory.
This mirrors what your asm application was doing - your 'C'
file was using a larger range of addresses you wanted to fill/clear
and so the comparison wasn't really a fair one.

Regards,
Mark

Edited by Wrathchild, Thu Oct 20, 2005 1:14 AM.

[devwebcl]

if you need speed you should use assembler, and for faster development can use high level language as cc65. anyway there are several optimization for C code as loop unroll.
trying to avoid division, modulos, etc (you can find in internet more information about it, I remember a pdf paper for Arm CPU optimization but it can be used for any C compiler).

for examples change loop (for(;<N;)) for the same N explicit commands of course only if you know how many iteration are going to be. in your example is very clear so this is it. (modulo division also I took it out)

the performance is much better but still it's as good as assembler code.
attached there are several examples of it.

cheers,

--devwebcl

#define poke(addr,val)  (*(unsigned char*) (addr) = (val))
#define pokew(addr,val) (*(unsigned*) (addr) = (val))
#define peek(addr)      (*(unsigned char*) (addr))
#define peekw(addr)     (*(unsigned*) (addr))

int main (void)
{
   int n = 0;
   int x = peekw(0x58);

   // Print chars in screen
  pokew(x+0,0);
  pokew(x+1,1);
  pokew(x+2,2);
  pokew(x+3,3);
  pokew(x+4,4);
  pokew(x+5,5);
  pokew(x+6,6);
  pokew(x+7,7);
  pokew(x+8,8);
  pokew(x+9,9);
  pokew(x+10,10);
  pokew(x+11,11);
  pokew(x+12,12);
  pokew(x+13,13);
  pokew(x+14,14);
  pokew(x+15,15);
  pokew(x+16,16);
  pokew(x+17,17);
  pokew(x+18,18);
  ...
  ...
  ...
  pokew(x+666,154);
  pokew(x+667,155);
  pokew(x+668,156);
  pokew(x+669,157);
  pokew(x+670,158);
  pokew(x+671,159);
  pokew(x+672,160);
  pokew(x+673,161);
  pokew(x+674,162);
  pokew(x+675,163);
  pokew(x+676,164);
  pokew(x+677,165);
  pokew(x+678,166);
  pokew(x+679,167);
  pokew(x+680,168);
  pokew(x+681,169);
  pokew(x+682,170);
  pokew(x+683,171);
  pokew(x+684,172);
  pokew(x+685,173);
  pokew(x+686,174);
  pokew(x+687,175);
  pokew(x+688,176);
  pokew(x+689,177);
  pokew(x+690,178);
  pokew(x+691,179);
  pokew(x+692,180);
  pokew(x+693,181);
  pokew(x+694,182);
  pokew(x+695,183);
  pokew(x+696,184);
  pokew(x+697,185);
  pokew(x+698,186);
  pokew(x+699,187);
  pokew(x+700,188);
  pokew(x+701,189);


   while(peekw(0xD01F)!=6) {  // Wait START
   }


}

Attached Files

•  pruebas.zip   16.55K   30 downloads

Edited by devwebcl, Fri Oct 21, 2005 6:51 AM.

[danwinslow]

Uh, well, no offense devwebcl but thats sort of unrealistic. Yes, its fast, but you might as well use assembler. Maybe thats your point

I find that its very good to write things up in C, and then use CC65's inline ASM function to hand optimize where necessary. Using single byte code *really* helps as well. And, remember you can do all the same look up math table tricks in C that you can in assembler, not to mention pointer arithmetic. Really, C is just a kind of very fancy macro assembler.

Edited by danwinslow, Thu Oct 20, 2005 3:42 PM.

[Shawn Jefferson]

danwinslow, on Thu Oct 20, 2005 1:40 PM, said:

And, remember you can do all the same look up math table tricks in C that you can in assembler, not to mention pointer arithmetic. Really, C is just a kind of very fancy macro assembler.

If you look in the graphics library I started, I used some lookup tables for just that reason. I'm sure more can be done there...

[devwebcl]

danwinslow, on Thu Oct 20, 2005 4:40 PM, said:

Uh, well, no offense devwebcl but thats sort of unrealistic. Yes, its fast, but you might as well use assembler. Maybe thats your point

no, no offense at all, this is a forum and it's here to write down our ideas
and yes, asm always is going to be the fastest language, but what I'm trying to show is that there are several optimization tricks for C language and the most famous is loop unrolling buecause in this way you avoid asm instructions in the final macro code when it's linking and compiling the C compiler

like we mentioned: also trying to avoid expensive functions like division, trigonometric, etc, there is better to use tables, use the basic word for variables (int usually is in C).
the for(; making it, the comparision always against zero. avoid recursion.

here there is a good article:
http://www.codeproje...ptimization.asp

--devwebcl

[Shawn Jefferson]

devwebcl, on Fri Oct 21, 2005 5:11 AM, said:

here there is a good article:
http://www.codeproje...ptimization.asp

That is a good article, but also read the cc65 documentation since a lot of optimizing C code is compiler/processor dependent.

http://www.cc65.org/doc/coding.html

For instance, unsigned int isn't the best data type to use on the 6502. unsigned char is what you would use. Also there is a mailing list for cc65 (check the www.cc65.org website) where several asm and C wizards can answer our questions. I know because I've asked all sorts of stupid questions of them.

[Allas]

Im in the middle of a simple game that use bitmappings, direct draw in screen and sprites. I read most of the ATARIGFX library. As Shawn said, sprites still dont work.

Another simple problem I found : inverse video text cant be printed in screen, only I get garbage in his place.

Do you get any progress in ATARIGFX? I feel I use every command , and im very happy with more functions added.

[Shawn Jefferson]

Allas, on Wed Nov 30, 2005 8:25 PM, said:

Im in the middle of a simple game that use bitmappings, direct draw in screen and sprites. I read most of the ATARIGFX library. As Shawn said, sprites still dont work.

Another simple problem I found : inverse video text cant be printed in screen, only I get garbage in his place.

Do you get any progress in ATARIGFX? I feel I use every command , and im very happy with more functions added. 

Sorry, I don't have time to do any development on it, that's why I released the source that I do have. There most likely are bugs in the ascii to screen routines that I wrote, and probably a better way to do it anyway.

[MrFish]

Allas, on Sat Oct 8, 2005 3:43 PM, said:

Well I finished to scan the Quickcode manual. If anyone put the ATR image of Quickcode will be a great help.

Thanks for the manual Allas. Has anyone come up with an ATR for this yet?

[MrFish]

8bitclassics, on Thu Oct 6, 2005 7:15 AM, said:

From what I have read (and now learning by typing in the manual), ACTION! is supposed to be pretty easy to learn and can be compiled.  Run-Time files have to be included with the distribution which limits it to being a disk I believe.  If you want to do a straight Binary file (for cartridge), one of the assembler's would probably would do you best, but harder to learn than say BASIC or ACTION!  If you do a google, you can find many reviews of them.  Also, the Wikipedia (http://www.wikipedia.org) has information on the different programmig languages for the Atari 8-Bit.

As for the action manual, should be done in a couple weeks.

Corey

How's it coming on the Action manual? Looking forward to this. BTW, thanks for the Basic XL manual. Great job.

[Allas]

MrFish, on Fri Dec 9, 2005 7:12 PM, said:

Allas, on Sat Oct 8, 2005 3:43 PM, said:

Well I finished to scan the Quickcode manual. If anyone put the ATR image of Quickcode will be a great help.

Thanks for the manual Allas. Has anyone come up with an ATR for this yet?

I cant believe any atarian in the earth have the Quikcode manual, specially the assembler coders. Quickcode its the best library for Assembler. But, I know someone who should have it. Just, the owner manual

That was 20 years ago...

Edited by Allas, Fri Dec 9, 2005 7:06 PM.