assembly - Finding out how many bytes separate esp and the stored return address on the program's stack -


i'm having trouble finding out answer. i've read %ebp has 32-bits, moving %esp %ebp you'll still have 32-bits, subtract 70 32, , don't understand rest. new i'm not proficient. please give detailed explanation. thank you!

below question having trouble with.

at end of sequence of instructions, how many bytes separate esp , stored return address on program's stack? assume called function using standard 32-bit x86 calling conventions.

804847c functioname: 804847c: push %ebp 804847d: mov %esp,%ebp 804847f: sub $0x70,%esp 8048482: movl $0x0,0x4(%esp) 804848a: movl $0x8048580,(%esp)

sub $0x70,%esp : reserve 0x70 bytes on stack.

movl $0x0,0x4(%esp) : place 0 32-bit value argument.

movl $0x8048580,(%esp) : place address. next ret jump it.

by standard calling convention, named cdecl, arguments placed on stack followed address callee should return to.


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