Welcome to ETO.
Your code will be easier to read if you use code tags to post it like this: [code=asm] place code here [/code]
As for the code itself, you are moving the value 100 to a counter and decrementing that each loop until it equals X (max value 30). If not equal to counter, you delay 100 us, decrease counter, and loop. When equal to X, you set an LED then continue looping until counter =0 and skip to something else.
One concern, assuming that interpretation is correct, is that 100x 100 us + a few instruction cycles = 10 ms + a little. I don't think you will see anything change. At least, the flask will be quick.
John