Slightly more complex fingerprint calculation; only needed for xor+

thomasmueller · thomasmueller · commit 83af74cb3def · 2018-10-22T10:29:50.000+02:00
diff --git a/src/xorfilter_plus.h b/src/xorfilter_plus.h
@@ -172,7 +172,7 @@ class XorFilterPlus {
   HashFamily* hasher;
 
   inline FingerprintType fingerprint(const uint64_t hash) const {
-    return (FingerprintType) hash;
+    return (FingerprintType) (hash ^ (hash >> 32));
   }
 
  public:

Original file line number	Diff line number	Diff line change
`@@ -172,7 +172,7 @@ class XorFilterPlus {`
`172`	`172`	`HashFamily* hasher;`
`173`	`173`
`174`	`174`	`inline FingerprintType fingerprint(const uint64_t hash) const {`
`175`		`- return (FingerprintType) hash;`
	`175`	`+ return (FingerprintType) (hash ^ (hash >> 32));`
`176`	`176`	`}`
`177`	`177`
`178`	`178`	`public:`