School Commit Init

Anul 1/Semestrul 1/ASC/Seminar 4/1.asm

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+bits 32 ; assembling for the 32 bits architecture
+
+; declare the EntryPoint (a label defining the very first instruction of the program)
+global start        
+
+; declare external functions needed by our program
+extern exit               ; tell nasm that exit exists even if we won't be defining it
+import exit msvcrt.dll    ; exit is a function that ends the calling process. It is defined in msvcrt.dll
+                          ; msvcrt.dll contains exit, printf and all the other important C-runtime specific functions
+
+; our data is declared here (the variables needed by our program)
+segment data use32 class=data
+    ; ...
+    a db "coaie"
+    l equ $-$$
+    b resb l
+; our code starts here
+segment code use32 class=code
+    start:
+        ; ...
+        mov ESI,a
+        mov EDI,b
+        mov ECX,l
+        cld
+        jecxz end
+        label:
+            lodsb
+            sub al,"a"-"A"
+            stosb
+        loop label
+        end:
+        ; exit(0)
+        push    dword 0      ; push the parameter for exit onto the stack
+        call    [exit]       ; call exit to terminate the program