Jumping to TSS

[Perica]

..

[Pype.Clicker]

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push byte 12

is encoded as 0x6A 0x0C. when executed, it will put 0x00000012 on the stack (32 bytes, i don't remember if the value is sign-extended or zero-extended)

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 push 12 

is 0x68 0x0C 0x00 0x00 0x00, but it will have the very same effect on the stack.

http://courses.ece.uiuc.edu/ece291/arch ... f-pop.html

this should be all explained in the nasm docs as well ...

[Tim]

So when retrieving arguments from the stack, i should take into account the padding??

No -- the opposite. You can assume that anything on the stack is a dword.

If you have a function like:

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void fn(unsigned char a, unsigned short b, unsigned long c, unsigned long long d);

...the stack will look like:
[tt]00 00 00 aa
00 00 bb bb
cc cc cc cc
dd dd dd dd
dd dd dd dd[/tt]
That is, a and b are padded with zeroes; c is unchanged; and d is split across two dwords. If a and b were signed then they would be padded with copies of their top bits; that is, 0xFF if they are negative, or 0x00 if they are zero or positive.

[shad]

Is it me, or is the information (free information) on task switching (hardware or software) really this scarce?