Parsing HTTP verbs appeared to be the fastest when we use a compile-time trie: a series of nested switch statements. I could not believe that a perfect hash function is not better, and that led to a novel hashing approach that is based on the instruction PEXT (Parallel Bits Extract). - 0x80.pl / HN

see also

• Faster than Rust and C++: the PERFECT hash table - unordered_map 34M/s / gperf 122M/s / _mm_cmpestrc - 178M/s / movemask 186M/s / ptest 189M/s
  • benchmarking with perf
  • cmovne - branch optimisation - 306M/s / 312M/s