// This is the Hash128to64 function from Google's cityhash (available
// under the MIT License). We use it to reduce multiple 64 bit hashes
// into a single hash.
-inline size_t hash_128_to_64(const size_t upper, const size_t lower) {
+inline uint64_t hash_128_to_64(const uint64_t upper, const uint64_t lower) {
// Murmur-inspired hashing.
- const size_t kMul = 0x9ddfea08eb382d69ULL;
- size_t a = (lower ^ upper) * kMul;
+ const uint64_t kMul = 0x9ddfea08eb382d69ULL;
+ uint64_t a = (lower ^ upper) * kMul;
a ^= (a >> 47);
- size_t b = (upper ^ a) * kMul;
+ uint64_t b = (upper ^ a) * kMul;
b ^= (b >> 47);
b *= kMul;
return b;