Difference between revisions of "Assembly Language IF ELSE"

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(Assembly Version)
 
Line 19: Line 19:
 
     MOV R1, #0
 
     MOV R1, #0
 
     CMP R0, #10
 
     CMP R0, #10
     BNE .else
+
     BNE else
 
     MOV R1, #9
 
     MOV R1, #9
     B .endif
+
     B endif
  .else
+
  else:
 
     ADD R0, R0, #1
 
     ADD R0, R0, #1
  .endif
+
  endif:
  
  

Latest revision as of 10:28, 22 January 2020

C# example

int y = 0;
int x = 0;
if (y == 10)
{
    x = 9;
}
else
{
    y++
}

Assembly Version

   MOV R0, #0
   MOV R1, #0
   CMP R0, #10
   BNE else
   MOV R1, #9
   B endif
else:
   ADD R0, R0, #1
endif:


Line 1 sets the value of Register 0 to the value 0.
Line 2 sets the value of Register 1 to the value 0.
Line 3 compares the value in Register 0 with the value 10.
Line 4 will branch to the .else label if the previous compare was NOT EQUAL.
Line 5 will move the value 9 into Register 1.
Line 6 will branch always to the .endif label.
Line 7 is a label called .else and is used in a branch.
Line 8 will add together the value 1 with the current value in Register 0, the output will be stored back in Register 0.