func borrowingSub(a, b: uint64; borrowIn: bool): (uint64, bool) {.inline,
    noinit, ...raises: [], tags: [], forbids: [].}

func carryingAdd(a, b: uint64; carryIn: bool): (uint64, bool) {.inline, noinit,
    ...raises: [], tags: [], forbids: [].}

func narrowingDiv(uHi, uLo, v: uint64): (uint64, uint64) {.inline, noinit,
    ...raises: [], tags: [], forbids: [].}

func wideningMul(a, b: int64): (int64, uint64) {.inline, noinit, ...raises: [],
    tags: [], forbids: [].}

func wideningMul(a, b: uint64): (uint64, uint64) {.inline, noinit, ...raises: [],
    tags: [], forbids: [].}

func wideningMulAdd(a, b, c, d: uint64): (uint64, uint64) {.inline, noinit,
    ...raises: [], tags: [], forbids: [].}

func wideningMulAdd(a, b, c: uint64): (uint64, uint64) {.inline, noinit,
    ...raises: [], tags: [], forbids: [].}