[AD] Use MMX to get fast

["RogerioUP" <rogerup@xxxxxxxxxx>]

I use a simple MMX function to move images from memory to video and the time to transfer is much faster than allegro (half of time). Now I'm using Allegro because I'm having a lot of problems with direct accesses to new hardwares; Before, I used my own Operating System.

I don't know how the allegro make blit's, if it uses "rep movsd" or card accelerated commands. I have a card with VESA 3.0 and my routine is much faster than allegro. I create a routine called "repmovsq" it transfer 8 bytes (Quad Word) per cycle, just using:

 

            mov      ecx,(num of bytes) / 8

    loopq:

            movq    MM0,[esi]                        ; esi = source index

            movq    [edi],MM0                        ; edi = destination index

            add      esi,8

            add      edi,8

            dec      ecx

            jnz       loopq

            ;

            ; here the complement if (num of bytes) is not a multiple of 8

            ;

 

;

; opcodes

; movq    MM0,[esi] = 0x0F, 0x6F, 0x06

; movq    [edi],MM0 = 0x0F, 0x7F, 0x07

;

 

 

My English is not better because I'am brazilian

best Regards, Rogerio Uchoas Penchel

 

rogerup@xxxxxxxxxx