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Teehee
LOOP ?
everybody say it is slow and should be replaced by Jcc instr. .. Which others instructions are "useless"? _________________ Sorry if bad english. |
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19 Jun 2011, 17:56 |
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ouadji
jecxz ? _________________ I am not young enough to know everything (Oscar Wilde)-  |
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19 Jun 2011, 20:20 |
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edfed
xchg ebp,ebp
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19 Jun 2011, 20:28 |
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typedef
ouadji wrote:
Hmmmm ? Would you rather Code: cmp ecx,0 je .xxx |
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19 Jun 2011, 21:07 |
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Teehee
edfed wrote: xchg ebp,ebp not so useless: a 2-bytes NOP  _________________ Sorry if bad english. |
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19 Jun 2011, 21:51 |
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vid
Where is tom when we need him?
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19 Jun 2011, 21:56 |
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ouadji
Code: or ecx,ecx
jz mylabel with "jecxz" the jump is limited to 128 bytes, in many cases it's not enough. There should be a "near version" of jecxz ! and it seems that it's faster too! (??) _________________ I am not young enough to know everything (Oscar Wilde)- |
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19 Jun 2011, 22:41 |
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Tyler
lea is pretty pointless.
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20 Jun 2011, 03:33 |
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mindcooler
jecxz is pretty useless if you use ebx as your counter
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20 Jun 2011, 04:34 |
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idle
sub eax,eax
cmovnz eax,[eax] |
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20 Jun 2011, 11:28 |
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Teehee
Tyler wrote: lea is pretty pointless. ++++++++++++++1 _________________ Sorry if bad english. |
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20 Jun 2011, 11:54 |
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Overflowz
Quote: lea is pretty pointless. No way! It' saves alot of work for me :p |
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20 Jun 2011, 12:17 |
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edfed
lea is good, it means:
X=Y*scale+Z+Constant then, it is not so pointless, it is some advanced signal processing instruction. |
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20 Jun 2011, 12:35 |
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JohnFound
"loop" is great instruction for programmers (also string instructions) it is not our fault they are slow. In most cases using "loop" makes your code readable and small.
For example FASM uses "non optimal" instructions all over the source, but it is still, the fastest assembler in the world. How is it possible? Meditate on this. |
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20 Jun 2011, 12:45 |
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revolution
FFREE
Does anyone actually use it in a beneficial way? |
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20 Jun 2011, 13:46 |
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idle
fnop - dangerous nop ?
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20 Jun 2011, 14:44 |
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cod3b453
I'd go for ud2
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20 Jun 2011, 18:27 |
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xleelz
what is std and cld good for?
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21 Jun 2011, 01:43 |
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revolution
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21 Jun 2011, 01:55 |
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