Fibonacci hashing takes the form of "h * k>>(64-b)", where k is determined by golden ratio and b is the bit size of the table. This involves one generic multipl

Fibonacci hashing takes the form of "h * k>>(64-b)", where k is determined by golden ratio and b is the bit size of the table. This involves one generic multiplication, which is the bottleneck. This multiplication is not strictly necessary. You can replace it with k=1033 for example, which can be implemented as "h+(h<<10)+(h<<3)". This will be a good enough safeguard against naive hash functions but is much faster to compute. With "h * k>>(64-b)", the result has a cycle of 2^b. Suppose b=3 and you have input 1<<3|1, 2<<3|1 and 3<<3|1, Fibonacci hashing will put them to the same bucket – it is not that effective. A safer strategy is to use a proper integer hash function like Thomas Wang's 32-bit hash function. Although it involves more steps, it only involves plus and bit operations and probably can be computed faster than generic multiplication. At the end of day, however, Fibonacci hashing or similar ideas only helps when you hash keys to similar integers but has no effect when you hash different keys to the same integer. You have to use a reasonable hash function anyway.