From: Warren Smith

uint64 Rand64(){   uint i;   uint64 v;   v = statevec[0];   for(i=NumWordsInState-1; i>0; i--){ //can be unrolled and all loop iterations run parallel     v ^= statevec[i];     statevec[i] += UpdatorF(statevec[i-1]);   }   statevec[0] += RandStrideConst;   return(v); //returns the XOR of all words in state vector }

I like the idea, but that XOR worries me. You've not demonstrated independence of the bits being XORed together and therefore the XOR may cancel out randomness. Phil