HW1 Determinant counter

.text

.global count_det

count_det:
        LDR r1, [r0, #16]
        LDR r2, [r0, #32]
        MUL r1, r2, r1
        LDR r2, [r0, #0]
        MUL r1, r2, r1
        MOV r3, r1

        LDR r1, [r0, #20]
        LDR r2, [r0, #28]
        MUL r1, r2, r1
        LDR r2, [r0, #0]
        MUL r1, r2, r1
        SUB r3, r3, r1

        LDR r1, [r0, #4]
        LDR r2, [r0, #12]
        MUL r1, r2, r1
        LDR r2, [r0, #32]
        MUL r1, r2, r1
        SUB r3, r3, r1

        LDR r1, [r0, #4]
        LDR r2, [r0, #20]
        MUL r1, r2, r1
        LDR r2, [r0, #24]
        MUL r1, r2, r1
        ADD r3, r3, r1                                                                                                                                                                                                                                                                                                                                                                                                                        LDR r1, [r0, #8]                                                                                                                                                                                                   LDR r2, [r0, #12]
        MUL r1, r2, r1                                                                                                                                                                                                     LDR r2, [r0, #28]                                                                                                                                                                                                  MUL r1, r2, r1                                                                                                                                                                                                     ADD r3, r3, r1                                                                                                                                                                                                                                                                                                                                                                                                                        LDR r1, [r0, #8]
        LDR r2, [r0, #16]                                                                                                                                                                                                  MUL r1, r2, r1                                                                                                                                                                                                     LDR r2, [r0, #24]                                                                                                                                                                                                  MUL r1, r2, r1                                                                                                                                                                                                     SUB r3, r3, r1                                                                                                                                                                                                                                                                                                                                                                                                                        MOV r0, r3                                                                                                                                                                                                                                                                                                                                                                                                                            BX lr