Assembly Language IF

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C# example

int a = 0;
do
{
    a++
}
while ( A != 99);

Assembly Version

   LDR R0, #0
.loop
   ADD R0, R0, #1
   CMP R0, #99
   BNE .loop

Line 1 sets the value of Register 0 to the value 0. Line 2 is a label which will be used to branch too. Line 3 adds the value 1 to the current value in Register 0 and stores the value back into Register 0. Line 4 compares the value in Register 0 with the value 99. Line 5 will branch to the .loop label if the previous compare was NOT EQUAL.