circuitpython/tests/inlineasm/asmblbx.py

# test bl and bx instructions

@micropython.asm_thumb
def f(r0):
    # jump over the internal functions
    b(entry)

    label(func1)
    add(r0, 2)
    bx(lr)

    label(func2)
    sub(r0, 1)
    bx(lr)

    label(entry)
    bl(func1)
    bl(func2)

print(f(0))
print(f(1))