[Pgubook-readers] Introduction and question

[Pupeno]

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Hello readers,
I have just found out about this book, Programming from the Ground Up 
obviusly, and I have download it and I'm reading it and learning a lot.
I'd like to start by thanking Jonathan Bartlett for writting what so far (page 
41) is an excelent book and offering it for free. Putting it in a place like 
savannah, making a mailing list and so on was a great idea. It makes me not 
feel alone in the process of readint it and learning. Thank you a lot 
Jonathan Bartlett!!!!!!
Now, the question. I have just read the full explanation of maximum.s, a 
program that looks for the maximum number in a list of numbers... the second 
program in the book.
The first thing I didn't like was the pre-fetch of a value. That is, it 
fetches a value from the list, puts it into a register an then the loops 
starts. And obviusly, during the loops, more values are fetched (with exactly 
the same sentence). The fact is that I've been programming for more than 10 
years already and I never liked that kind of things: sentences that are 
repeated, inside and outside of a loop. Is there any good reason to have done 
it that way ? I proposed myself re-work it to make it the way I like it and 
it is even shorter and I think, maybe easier to understand (the resulting 
source is at the end). Maybe, I'm just missing something, or was it just 
pedagojical or just because, I don't know.
Anyway, thanks again to Jonathan Bartlett!!!!
- -- 
Pupeno: address@hidden - http://www.pupeno.com

PS: I've filled some 'support request' at the savannah tracker. They are more 
like bug reports... anyway, will they be ever noticed ?

PSPS: The source code:
 .section .data

data_items:
 .long 3,67,34,222,45,75,54,34,44,33,22,11,66,0

 .section .text

 .globl _start
_start:
 # Put 0 in %edi, the index register.
 movl $0, %edi
 
 # Put 0 in %ebx, the largest item so far (this will limit us to work with 
numbers greater than 0, but we are already limited to that).
 movl $0, %ebx

start_loop:
 # Put the next number into %eax.
 movl data_items(,%edi,4), %eax  
 
 # Compare the just-fetched number, %eax, to 0.     
 cmpl $0, %eax
 
 # If it is 0, jump to loop_exit, finish the program.
 je loop_exit
 
 # Increment the index for the next interation.
 incl %edi
 
 # Compare the current biggest number, %ebx, to the new number, %eax.
 cmpl %ebx, %eax
 
 # If the newest number, %eax, is lower or equal, continue fetching numbers.
 jle start_loop
 
 # If not, store a new biggest number...
 movl %eax, %ebx
 
 # And continuew looping.
 jmp start_loop

loop_exit:
 movl $1, %eax
 int $0x80
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