Question

Create a procedure named CreateRandomString that generates a random string of length L =20, containing all capital letters. When calling the CreateRandomString procedure, pass the value of L in EAX, and pass a pointer to an array of byte that will hold the random string. Write a test program in the main procedure that calls your procedure 10 times and displays the strings in the console window.

Answer 1

.LC0:

.string "Before swapping"

.LC1:

.string "a = "

.LC2:

.string "b = "

.LC3:

.string "\\After swapping"

main:

push rbp

mov rbp, rsp

sub rsp, 16

mov DWORD PTR [rbp-4], 1

mov DWORD PTR [rbp-8], 2

mov esi, OFFSET FLAT:.LC0

mov edi, OFFSET FLAT:std::cout

call std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)

mov esi, OFFSET FLAT:std::basic_ostream<char, std::char_traits<char> >& std::endl<char, std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&)

mov rdi, rax

call std::basic_ostream<char, std::char_traits<char> >::operator<<(std::basic_ostream<char, std::char_traits<char> >& (*)(std::basic_ostream<char, std::char_traits<char> >&))

mov esi, OFFSET FLAT:.LC1

mov edi, OFFSET FLAT:std::cout

call std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)

mov rdx, rax

mov eax, DWORD PTR [rbp-4]

mov esi, eax

mov rdi, rdx

call std::basic_ostream<char, std::char_traits<char> >::operator<<(int)

mov esi, OFFSET FLAT:std::basic_ostream<char, std::char_traits<char> >& std::endl<char, std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&)

mov rdi, rax

call std::basic_ostream<char, std::char_traits<char> >::operator<<(std::basic_ostream<char, std::char_traits<char> >& (*)(std::basic_ostream<char, std::char_traits<char> >&))

mov esi, OFFSET FLAT:.LC2

mov edi, OFFSET FLAT:std::cout

call std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)

mov rdx, rax

mov eax, DWORD PTR [rbp-8]

mov esi, eax

mov rdi, rdx

call std::basic_ostream<char, std::char_traits<char> >::operator<<(int)

mov esi, OFFSET FLAT:std::basic_ostream<char, std::char_traits<char> >& std::endl<char, std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&)

mov rdi, rax

call std::basic_ostream<char, std::char_traits<char> >::operator<<(std::basic_ostream<char, std::char_traits<char> >& (*)(std::basic_ostream<char, std::char_traits<char> >&))

lea rdx, [rbp-8]

lea rax, [rbp-4]

mov rsi, rdx

mov rdi, rax

call swap(int&, int&)

mov esi, OFFSET FLAT:.LC3

mov edi, OFFSET FLAT:std::cout

call std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)

mov esi, OFFSET FLAT:std::basic_ostream<char, std::char_traits<char> >& std::endl<char, std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&)

mov rdi, rax

call std::basic_ostream<char, std::char_traits<char> >::operator<<(std::basic_ostream<char, std::char_traits<char> >& (*)(std::basic_ostream<char, std::char_traits<char> >&))

mov esi, OFFSET FLAT:.LC1

mov edi, OFFSET FLAT:std::cout

call std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)

mov rdx, rax

mov eax, DWORD PTR [rbp-4]

mov esi, eax

mov rdi, rdx

call std::basic_ostream<char, std::char_traits<char> >::operator<<(int)

mov esi, OFFSET FLAT:std::basic_ostream<char, std::char_traits<char> >& std::endl<char, std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&)

mov rdi, rax

call std::basic_ostream<char, std::char_traits<char> >::operator<<(std::basic_ostream<char, std::char_traits<char> >& (*)(std::basic_ostream<char, std::char_traits<char> >&))

mov esi, OFFSET FLAT:.LC2

mov edi, OFFSET FLAT:std::cout

call std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)

mov rdx, rax

mov eax, DWORD PTR [rbp-8]

mov esi, eax

mov rdi, rdx

mov eax, 0

leave

ret

swap(int&, int&):

push rbp

mov rbp, rsp

mov QWORD PTR [rbp-24], rdi

mov QWORD PTR [rbp-32], rsi

mov rax, QWORD PTR [rbp-24]

mov eax, DWORD PTR [rax]

mov DWORD PTR [rbp-4], eax

mov rax, QWORD PTR [rbp-32]

mov edx, DWORD PTR [rax]

mov rax, QWORD PTR [rbp-24]

mov DWORD PTR [rax], edx

mov rax, QWORD PTR [rbp-32]

mov edx, DWORD PTR [rbp-4]

mov DWORD PTR [rax], edx

nop

pop rbp

ret

__static_initialization_and_destruction_0(int, int):

push rbp

mov rbp, rsp

sub rsp, 16

mov DWORD PTR [rbp-4], edi

mov DWORD PTR [rbp-8], esi

cmp DWORD PTR [rbp-4], 1

jne .L6

cmp DWORD PTR [rbp-8], 65535

jne .L6

mov edi, OFFSET FLAT:std::__ioinit

call std::ios_base::Init::Init()

mov edx, OFFSET FLAT:__dso_handle

mov esi, OFFSET FLAT:std::__ioinit

mov edi, OFFSET FLAT:std::ios_base::Init::~Init()

call __cxa_atexit

.L6:

nop

leave

ret

_GLOBAL__sub_I_main:

push rbp

mov rbp, rsp

mov esi, 65535

mov edi, 1

call __static_initialization_and_destruction_0(int, int)

pop rbp

ret