;****Convert the following 32-bit Nasm (P5a.asm) program to 64 bit (P5a_64.asm). Skeletal code for (P5a_64.asm) is provided at the bottom.

; Output must be the same for both, cannot change anything in .data section

; nasm -f elf32 P5a.asm && gcc -m32 -o P5a P5a.

extern printf

extern strlen

section .data

msg db "Testing:",0xA,0x0

len equ $ - msg

msg2 db "The length is: ",0x0

len2 equ $ - msg2

fmt db "%s",0xA,0x0

lfmt equ $ -fmt

fmt2 db "%u",0xA,0x0

lfmt2 equ $ - fmt2

t1 db "This is a test.",0x0

l1 equ $ - t1

t2 db "Newline test.",0xA,0x0

l2 equ $ - t2

t3 db 0xA,0x0

l3 equ $ - t3

t4 db 0x0

l4 equ $ - t4

section .bss

ta resd 4

retv resd 1

section .text

global main

main:

push ebp ; Save stack frame pointer

mov ebp, esp ; Setup a stack frame

; Setup tests

mov dword [ta], t1 ; 0

mov dword [ta+4], t2 ; 1

mov dword [ta+8], t3 ; 2

mov dword [ta+12], t4 ; 3

mov ecx, 3

loop:

mov esi, [ta+ecx*4]

push ecx ; Save ECX from potential clobbering

; printf(msg)

push dword msg ; Push the argument into the stack

call printf ; Call the function

add esp, byte 4 ; Clean the stack

; printf("%s ",ta)

push esi ; Push the argument into the stack

push dword fmt ; Push the argument into the stack

call printf ; Call the function

add esp, byte 8 ; Clean the stack

; retv = strlen(ta)

push esi ; Push the argument into the stack

call strlen ; Call the function

add esp, byte 4 ; Clean the stack

mov [retv], eax ; Save return value

; printf(msg2)

push dword msg2 ; Push the argument into the stack

call printf ; Call the function

add esp, byte 4 ; Clean the stack

; printf("%u ",retv)

push dword [retv] ; Push the argument into the stack

push dword fmt2 ; Push the argument into the stack

call printf ; Call the function

add esp, byte 8 ; Clean the stack

pop ecx

dec ecx ; Decrement counter

jns loop ; Jump while non-negative

mov esp, ebp ; Undo stack frame

pop ebp ; Restore stack frame pointer

mov eax, 0 ; main() return value

ret

;**************************************************************

;Following is P5a_64.asm skeletal code

; nasm -f elf64 P5a_64.asm && gcc -m64 -o P5a_64 P5a_64.o

extern printf

extern strlen

section .data

msg db "Testing:",0xA,0x0

len equ $ - msg

msg2 db "The length is: ",0x0

len2 equ $ - msg2

fmt db "%s",0xA,0x0

lfmt equ $ -fmt

fmt2 db "%u",0xA,0x0

lfmt2 equ $ - fmt2

t1 db "This is a test.",0x0

l1 equ $ - t1

t2 db "Newline test.",0xA,0x0

l2 equ $ - t2

t3 db 0xA,0x0

l3 equ $ - t3

t4 db 0x0

l4 equ $ - t4

section .bss

; add your bss section data here

section .text

global main

main:

; add your main code here

; some kind of loop, for every test message

; printf(msg)

; printf("%s ",ta)

; retv = strlen(ta)

; printf(msg2)

; printf("%u ",retv)

;**********************************

;Sample Output

Testing:

The length is: 0 Testing:

The length is: 1 -->a space is of length 1 Testing: Newline test.

The length is: 14 --> 14 spaces in the last example (NewLine test.) Testing:

This is a test. The length is: 15