/*******************************************************
*         File:  while_loop_ex_Delay_w_annul.m
*          Dir:  cis235/Examples
*         Date:  Sept 25, 2002
*       Author:  DSS
*     Computer:  KUNET suns
*    Assembler:  as under the gcc compiler                 
*      Compile:  sa while_loop_ex_Delay_w_annul
*      Execute:  while_loop_ex_Delay_w_annul
*      Purpose:  implement a while loop branch
*******************************************************/
/* While loop to implement
int temp;
int x = 0;
int y = 0x9;
int z = 0x42;

temp = y;
while( temp > 0 ) {
    x = x + z;
    temp = temp - 1;
}
*/

        .data
x:      .word   0
y:      .word   0x9
z:      .word   0x42

        .text
start:  set     y, %r1
        ld      [%r1], %r2        ! we'll use %r2 for temp
        set     z, %r1
        ld      [%r1], %r3        ! we'll use %r3 for z
        mov     %r0, %r4          ! we'll use %r4 for x

        add     %r2, 1, %r2       ! set up for decrement
top:    subcc   %r2, 1, %r2       ! temp - 1 --> temp
        bg,a    top               ! temp > 0 ?
        add     %r4, %r3, %r4     ! x + z --> x

        set     x, %r1
        st      %r4, [%r1]        ! store x
end:    ta      0