Remove first prefetch.

The rationale behind this being that it is close too close to the first access of the data pointed by the pointer and is of no significant improvement as seen in the benchmarks.

PiperOrigin-RevId: 670574898
Change-Id: I43a495f23871a2870f4ffd9ab9232083d9668c79

absl/hash/internal/low_level_hash.cc

@@ -33,8 +33,6 @@ static uint64_t Mix(uint64_t v0, uint64_t v1) {
 
 
 uint64_t LowLevelHashLenGt16(const void* data, size_t len, uint64_t seed,
 uint64_t LowLevelHashLenGt16(const void* data, size_t len, uint64_t seed,
                              const uint64_t salt[5]) {
                              const uint64_t salt[5]) {
-  // Prefetch the cacheline that data resides in.
-  PrefetchToLocalCache(data);
   const uint8_t* ptr = static_cast<const uint8_t*>(data);
   const uint8_t* ptr = static_cast<const uint8_t*>(data);
   uint64_t starting_length = static_cast<uint64_t>(len);
   uint64_t starting_length = static_cast<uint64_t>(len);
   const uint8_t* last_16_ptr = ptr + starting_length - 16;
   const uint8_t* last_16_ptr = ptr + starting_length - 16;