XXH64_round
val = XXH64_round(0, val);
v1 = XXH64_round(v1, XXH_get64bits(p)); p+=8;
v2 = XXH64_round(v2, XXH_get64bits(p)); p+=8;
v3 = XXH64_round(v3, XXH_get64bits(p)); p+=8;
v4 = XXH64_round(v4, XXH_get64bits(p)); p+=8;
U64 const k1 = XXH64_round(0, XXH_get64bits(p));
state->v1 = XXH64_round(state->v1, XXH_readLE64(state->mem64+0, endian));
state->v2 = XXH64_round(state->v2, XXH_readLE64(state->mem64+1, endian));
state->v3 = XXH64_round(state->v3, XXH_readLE64(state->mem64+2, endian));
state->v4 = XXH64_round(state->v4, XXH_readLE64(state->mem64+3, endian));
v1 = XXH64_round(v1, XXH_readLE64(p, endian)); p+=8;
v2 = XXH64_round(v2, XXH_readLE64(p, endian)); p+=8;
v3 = XXH64_round(v3, XXH_readLE64(p, endian)); p+=8;
v4 = XXH64_round(v4, XXH_readLE64(p, endian)); p+=8;
U64 const k1 = XXH64_round(0, XXH_readLE64(p, endian));