36 lines
1.4 KiB
NASM
36 lines
1.4 KiB
NASM
bits 32 ; assembling for the 32 bits architecture
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; declare the EntryPoint (a label defining the very first instruction of the program)
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global start
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; declare external functions needed by our program
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extern exit,printf,scanf ; tell nasm that exit exists even if we won't be defining it
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import exit msvcrt.dll ; exit is a function that ends the calling process. It is defined in msvcrt.dll
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; msvcrt.dll contains exit, printf and all the other important C-runtime specific functions
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import printf msvcrt.dll ; printf is a function that prints a string to the standard output. It is defined in msvcrt.dll
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import scanf msvcrt.dll ; scanf is a function that reads a string from the standard input. It is defined in msvcrt.dll
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; our data is declared here (the variables needed by our program)
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segment data use32 class=data
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; ...
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message db "n=",0
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n dd 0
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read db "%d",0
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; our code starts here
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segment code use32 class=code
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start:
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; ...
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;Write a programs that prints the message "n=" on the screen and then read from keyword the value for the signed number n
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push dword message
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call [printf]
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add ESI,4*1
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push dword n
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push dword read
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call [scanf]
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add ESI,4*2
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; exit(0)
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push dword 0 ; push the parameter for exit onto the stack
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call [exit] ; call exit to terminate the program
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