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Necromancer13



Joined: 18 Oct 2007
Posts: 32
Location: Ukraine
Necromancer13
FASM converts
Code:
cmp word[var],'MZ'
    

to
Code:
cmp word ptr [var],5A4D
    


but not to
Code:
cmp word ptr [var],4D5A
    


But 'MZ' is 4D5A, not 5A4D!
is it a bug?

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Post 22 Oct 2007, 05:16
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LocoDelAssembly
Your code has a bug


Joined: 06 May 2005
Posts: 4633
Location: Argentina
LocoDelAssembly
http://flatassembler.net/docs.php?article=faq (and perhaps somewhere in the documentation but by a quick search I wasn't able to find it)

Quote:
Why the instruction mov eax,'ABCD' is assembled into mov eax,44434241h? Shouldn't it be reversed?

Altough the most of other assemblers interpret quoted values treating the first character as the most significant, I've decided to use this different approach, just because it's more handy in the most situations. That's because for x86 architecture the least significant byte is the first byte in memory, so if you want to check whether there is 'ABCD' string at ebx address, you can just write cmp dword [ebx],'ABCD'.
Post 22 Oct 2007, 05:22
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Necromancer13



Joined: 18 Oct 2007
Posts: 32
Location: Ukraine
Necromancer13
ok.. thanks:)
Post 22 Oct 2007, 05:29
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