# expected: 0000000000000000, FFFFFFFFFFFFFFFF, 0000000000000010, 0000000000000000
    .text
_start:
    # 0 addition
    li x1, 0
    addw x31, x0, x1

    # all bits addition + sign extension to 32 bits then 64 bits
    li x1, 0x00000000FFFFFFFF
    addw x31, x0, x1

    # simple addition
    li x1, 8
    li x2, 8
    addw x31, x1, x2

    # 32bits trim
    li x1, 0xFFFFFFFF00000000
    addw x31, x0, x1