overflow_uint64.go

// addOrMax performs safe addition: if result overflows, it returns MaxUint64
func addOrMax(accum, value uint64) uint64 {
	if (accum + value) < accum {
		return math.MaxUint64
	} else {
		return accum + value
	}
}

// subOrZero performs safe subtraction: if result underflows, it returns 0
func subOrZero(accum, value uint64) uint64 {
	if accum >= value {
		return accum - value
	} else {
		return 0
	}
}

// mulOrMaxIfOverflows performs safe multiplication: if result overflows, it returns MaxUint64
func mulOrMaxIfOverflows(a, b uint64) uint64 {
	if mulOverflows(a, b) {
		return math.MaxUint64
	} else {
		return a * b
	}
}

// mulOverflows checks for overflow
func mulOverflows(a, b uint64) bool {
	if a <= 1 || b <= 1 {
		return false
	}
	c := a * b
	return c/b != a
}