https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126351
--- Comment #4 from ktkachov at gcc dot gnu.org --- (In reply to Drea Pinski from comment #3) > Coremarks is a bad benchmark. Sure, but in this case it acts as a microbenchmarking harness for the two sequences. If CRC calculation is actually important for performance in an application then it's likely called multiple times, which would put the table in the cache. The PMULL sequence is more instructions overall, uses SIMD (which usually has higher latency and lower throughput than simple scalar ops) and contains 4xGP<->FP moves so can't possibly win against a cache-hitting load. Note this applies only for QImode crc. For larger sizes I think we should still prefer the PMULL sequence
