while (a != b) {
    if (a > b) {
        a -= b;
    } else {
        b -= a;
    }
}
/*
start:
    if (a == b) goto end


    if (a <= b) goto elsecase
    a -= b
    goto endif
elsecase:
    b -= a
endif:

    goto start
end:
*/

/*
symbol table:
    a @ 0x80
    b @ 0x81
    end @ 0x84

temp:
    c = r0
    d = r1

start:
    c = a           R0 = load from 0x80     6,0,3;  0x80        63 80
    d = b           R1 = load from 0x81     6,1,3;  0x81        67 81
    d = -d                                  5,1,1               55
    c += d
    c = !c
    c = !c
    if c <= 0: goto end     R2 = load from 0x84; goto
                            6,2,3;  0x84        6B 84
                            7,0,2               72


    if (a <= b) goto elsecase
    a -= b
    goto endif
elsecase:
    b -= a
endif:

    goto start
end:
*/