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cassemblypdp-11

sub-routines on Assembly

can I do something like this on Assembly bne jsr swap, if not how can I solve this problem from C, thanks in advance

if(start!=pivot_index){
  swap(board,start,pivot_index);
 }

I was taught that I must write jsr and sub-routine but can I do something like this bne sub-routine

Solution

  • In assembly that would usually be translated into something like this (pseudo-assembly):

    load [start]
compare [pivot_index]
branch-if-equal label1
push [pivot_index]
push [start]
push [board]
call swap
add-stack-pointer 12
label1:

    ie. the if statement is converted into a jump that jumps over the body of the if if the controlling expression is not true.