count_iter_19.sa

来自「dsp6713开发板的许多例程.对入门特别有用」· SA 代码 · 共 23 行

        .global _count_loop_iterations
_count_loop_iterations .cproc count
        .reg    i, iters, flag

        ZERO    iters               ; Initialize our return value to 0.

        CMPLT   count,  1,  flag
[flag]  B       does_not_iterate    ; Do not iterate if count < 1.

        MV      count,  i           ; i = count

loop:   .trip   1                   ; This loop is guaranteed to iterate at 
                                    ; least once.

        ADD     iters,  1,  iters   ; iters++
        SUB     i,      1,  i       ; i--
 [i]    B       loop                ; while (i &gt; 0);

does_not_iterate:

        .return iters                   ; Return our number of iterations.
        .endproc