Re: newbie questiom about %rip in x86-64 and var


Claudio Daffra wrote:
thx robert .

4004b0: c6 05 49 07 10 00 01 movb $0x1,1050441(%rip)
# 500c00 <uc>
4004b7: c6 05 42 07 10 00 01 movb $0x1,1050434(%rip)
# 500c00 <uc>

ok the offset change always.

the var is in virtual address 500c00 and rip is 4004b0 but
difficult i have mean the offset number
0x0105:0441
0x0105:0434

0x0050:0c00 -
0x0040:04b0 =
-------------------
0x0010:0750
distance from RIP and Virtual address refer memory?
not 0x0105:0441 or 0x0105:0434 .


First, don't write flat addresses in segmented (xxxx:yyyy) form, you'll
just confuse everyone.

Second, the offset in the source instruction "movb
$0x1,1050441(%rip)" is in *decimal*. So it's actually rip+0x100749 (or
0x100742 for the second instruction). And don't forget that rip is
assumed to point at the beginning of the the *next* instruction.

.

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