use mixhash

zhangyunhao116 · Oct 28, 2024 · 797b8ba · 797b8ba
1 parent cb7705f
commit 797b8ba
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Showing 2 changed files with 7 additions and 5 deletions.
diff --git a/bench_test.go b/bench_test.go
@@ -24,7 +24,8 @@ var (
 		2048,
 		4096,
 		8192,
-		1 << 16}
+		1 << 16,
+	}
 )
 
 func BenchmarkMapAccessHit(b *testing.B) {

diff --git a/hash.go b/hash.go
@@ -2,10 +2,11 @@ package umap
 
 import "math/bits"
 
-// Using FxHash: https://searchfox.org/mozilla-central/rev/633345116df55e2d37be9be6555aa739656c5a7d/mfbt/HashFunctions.h
-// Benchmarks for different hash algorithms: https://github.com/tkaitchuck/aHash/blob/master/FAQ.md#how-is-ahash-so-fast
+func _wymix(a, b uint64) uint64 {
+	hi, lo := bits.Mul64(a, b)
+	return hi ^ lo
+}
 
 func hashUint64(x uint64) uint64 {
-	const K = 0x517cc1b727220a95
-	return (bits.RotateLeft64(x, 5) ^ x) * K
+	return _wymix(x^0xfffc2d0600147fc8, 0xf6ea71d5ec8a2980)
 }