Difference between revisions of "Assembly Language IF"

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(Assembly Version)
Line 17: Line 17:
 
     BNE .loop
 
     BNE .loop
  
Line 1 sets the value of Register 0 to the value 0.
+
Line 1 sets the value of Register 0 to the value 0.<br>
Line 2 is a label which will be used to branch too.
+
Line 2 is a label which will be used to branch too.<br>
Line 3 adds the value 1 to the current value in Register 0 and stores the value back into Register 0.
+
Line 3 adds the value 1 to the current value in Register 0 and stores the value back into Register 0.<br>
Line 4 compares the value in Register 0 with the value 99.
+
Line 4 compares the value in Register 0 with the value 99.<br>
Line 5 will branch to the .loop label if the previous compare was NOT EQUAL.
+
Line 5 will branch to the .loop label if the previous compare was NOT EQUAL.<br>

Revision as of 09:41, 16 June 2017

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.