larger.s

	.data
scanf_fmt:
	.asciz	"%d"

printf_fmt:
	.asciz	"%d\n"

	.text
	.global	main
main:
	push	{fp, lr}        // Push the caller's register states
	mov	fp, sp		// Save stack pointer to a register (frame pointer reg)
	sub	sp, sp, #8	// Create 8 bytes for 2 int values on the stack (stack
				// grows from the end, thus substract)
	ldr	r0, =scanf_fmt	// Put the string address on r0 (1st argument to scanf)
	add	r1, sp, #4	// Put the address of the first local variable to r1
				// (2nd argument to scanf)
	bl	scanf		// scanf("%d", &a);
	ldr	r0, =scanf_fmt	// Since scanf overwrites r0, we re-assign it
	mov	r1, sp		// Put the address of the second local variable to r1
	bl	scanf		// scanf("%d", &b);
	ldr	r1, [sp, #4]	// Put the value of the first local variable to r1
	ldr	r2, [sp]        // Put the value of the second local variable to r2
	cmp	r1, r2		// Compare r1 and r2
	bge	.print		// If r1 >= r2, go print r1
	mov	r1, r2		// Otherwise, first set r1 = r2
.print:
	ldr	r0, =printf_fmt	// Put the string address on r0
	bl	printf		// Since r1 is already the value we want to print,
				// printf("%d\n", r1);
	mov	r0, #0		// return 0;
	mov	sp, fp		// Restore stack pointer from frame pointer reg
	pop	{fp, pc}        // Pop the caller's register states

length.s

        .data
printf_fmt:
        .asciz  "%d\n"

        .text
        .global main
main:
        push	{fp, lr}        // Push the caller's register states
        mov     fp, sp          // Save stack pointer to a register (frame pointer reg)
        sub     sp, sp, #104    // 13*8=104 bytes for string buffer
                                // (8-byte alignment for stack pointer  is required)
        mov     r0, sp          // Put the buffer start address on r0
        mov     r1, #101        // Set the size limit to 101 bytes (null-terminated)
        ldr     r2, =stdin      // Get the address of stdin global variable
        ldr     r2, [r2]        // Get the content of stdin global variable
        bl      fgets           // fgets(buf,101,stdin);
        mov     r1, sp          // r1 = &buf[0];
        b       .compare        // Start the compare loop
.next:
        add     r1, r1, #1      // r1++, loop for the next char
.compare:
        ldrb    r0, [r1]        // Read the current char
        cmp     r0, #0          // If it's the terminate char
        beq     .print          // Stop and print the result
        cmp     r0, #10         // Or if it's not the new line
        bne     .next           // loop for the next char
.print:
        ldr     r0, =printf_fmt // Put the string address in r0
        sub     r1, r1, sp      // Calculate the looped string length
        bl      printf          // Print the result
        mov     r0, #0          // return 0;
        mov     sp, fp          // Restore stack pointer from frame pointer reg
        pop	{fp, pc}        // Pop the caller's register states

sumarray.s

        .data
scanf_fmt:
        .asciz "%d"

printf_fmt:
        .asciz "%d\n"

        .text
        .global main
main:
        push	{fp, lr}        // Push the caller's register states
        mov     fp, sp          // Save stack pointer to a register (frame pointer reg)
        sub     sp, sp, #4      // 4 bytes for scanf int read
        mov     r4, #0          // sum
        mov     r5, #5          // count
.next:
        ldr     r0, =scanf_fmt
        mov     r1, sp
        bl      scanf
        ldr     r0, [sp]
        add     r4, r4, r0      // Sum the read int
        sub     r5, r5, #1      // Decrease count
        cmp     r5, #0          // If count down to 0, print
        bgt     .next

        ldr     r0, =printf_fmt
        mov     r1, r4
        bl      printf

        mov     r0, #0
        mov     sp, fp
        pop	{fp, pc}