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Index > Windows > offsets of ebp

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ishkabible



Joined: 13 Sep 2010
Posts: 54
ishkabible
ok so im making a simple jit assembler and was looking at how offsets of ebp work so i could use them for variables. it seems that instructions that take offsets of ebp take ebp as offsets from 0xD4FF012B. what is the significance of this value?

take this
Code:
mov dword[ebp-300],10
    


comes out
Code:
C785 D4FEFFFF 0A000000
    


the fist part is obliviously the instruction, the next part is [ebp-300], and the next part is 10. if you add 300 to 0xD4FEFFFF you get 0xD4FF012B. so what is the reason for having them be offsets of 0xD4FF012B ? am i right about how the instruction is read?
Post 05 Dec 2010, 19:49
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baldr



Joined: 19 Mar 2008
Posts: 1651
baldr
ishkabible,

Low-endian is the method of ix86 to interpret multi-byte values. 0xFFFFFED4+300 == 0 (dumping carry).

I liked the "obliviously" part. Wink
Post 05 Dec 2010, 20:48
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