optimized.S

_calculate_points:                      @ @calculate_points
@ BB#0:
        push    {r4, r7, lr}
        add     r7, sp, #4
        mov     r4, r0
        bl      _current_position_x
        str     r0, [r4]
        bl      _current_position_y
        str     r0, [r4, #4]
        pop     {r4, r7, pc}

points.c

typedef struct Point {
        int x;
        int y;
} Point;

int current_position_x (void) {
        return 5;
}

int current_position_y (void) {
        return 10;
}

void calculate_points (Point *result) {
        result->x = current_position_x();
        result->y = current_position_y();
}

test.S

        .section	__TEXT,__text,regular,pure_instructions
	.section	__TEXT,__textcoal_nt,coalesced,pure_instructions
	.section	__TEXT,__const_coal,coalesced
	.section	__TEXT,__picsymbolstub4,symbol_stubs,none,16
	.section	__TEXT,__StaticInit,regular,pure_instructions
	.syntax unified
	.section	__TEXT,__text,regular,pure_instructions
	.globl	_current_position_x
	.align	2
_current_position_x:                    @ @current_position_x
@ BB#0:
	movw	r0, #5 ; Set 5 as the return value
	bx	lr ; Jump to the return address

	.globl	_current_position_y
	.align	2
_current_position_y:                    @ @current_position_y
@ BB#0:
	movw	r0, #10 ; Set 10 as the return value
	bx	lr ; Jump to the return address

	.globl	_calculate_points
	.align	2
_calculate_points:                      @ @calculate_points
@ BB#0:
	push	{r7, lr} ; Save r7 (this is the previous frame pointer) and lr (this is the return address)
	mov	r7, sp ; Save the current stack pointer. This is the frame pointer.
	sub	sp, sp, #4 ; Allocate 4 bytes on the stack
	str	r0, [sp] ; Store the pointer to 'result' in the newly allocated stack space. Remember that arguments are passed starting at r0
	bl	_current_position_x ; Call current_position_x()
	ldr	r1, [sp] ; Load the pointer to 'result' from the stack
	str	r0, [r1] ; Store the return value of current_position_x() at result+0x0
	bl	_current_position_y ; Call current_position_y()
	ldr	r1, [sp] ; Load the pointer to 'result' from the stack
	str	r0, [r1, #4] ; Store the return value of current_position_x() at result+0x4
	mov	sp, r7 ;  Restore the saved stack frame pointer 
	pop	{r7, pc} ; Restore the caller's frame pointer, -and- restore the caller's return address.
                         ; We pop the lr value saved in the first instruction *into* pc, which causes a jump to the return address

	.section	__DATA,__objc_imageinfo,regular,no_dead_strip
L_OBJC_IMAGE_INFO:
	.long	0
	.long	0


.subsections_via_symbols