gistfile1.txt

Compiled with https://gcc.godbolt.org/ ARM gcc 4.8.2, flags -Os

void q(int* a, volatile int* b)
{
  *a=0;
  *b=1;
  *a=2;
  *b=3;
  *a=4;
}

q(int*, int volatile*):
        movs    r3, #1
        str     r3, [r1]
        movs    r3, #3
        str     r3, [r1]
        movs    r3, #4
        str     r3, [r0]
        bx      lr