Bubble Sort

        B main

array   DEFW    25,10,13,9,44,15,6,2,36,42

        ALIGN
main
        MOV R0,#0       ; array[R2]
        MOV R1,#0       ; array[R3]
        MOV R2,#0       ; current_index*4
        MOV R3,#0       ; (current_index+1)*4

        MOV R4,#9       ; array length-1
        MOV R5,#0       ; counter
        ; R6 could be used as a "sorted?" check but not required
        ADRL R7,array   ; array address

iloop   CMP R4,#1
        BEQ iend

        MOV R2,#0
        MOV R3,#4

jloop   CMP R5,R4
        BEQ jend

        LDR R0,[R7,R2]
        LDR R1,[R7,R3]

        CMP R0,R1
        BGT no_swap

        STR R0,[R7,R3]
        STR R1,[R7,R2]

no_swap ADD R2,R2,#4
        ADD R3,R3,#4
        ADD R5,R5,#1
        B jloop

jend    BL print
        SUB R4,R4,#1
        MOV R5,#0
        B iloop

iend    SWI 2

print   STMFD R13!, {R0-R7, R14}

        MOV R0,#0
        MOV R1,#0
        ADR R2,array

ploop   CMP R1,#40
        BEQ pend
        LDR R0,[R2,R1]
        SWI 4
        MOV R0,#44
        SWI 0
        ADD R1,R1,#4
        B ploop

pend    MOV R0,#13
        SWI 0
        LDMFD R13!, {R0-R7, PC}