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Diffstat (limited to 'vendor/github.com/cespare/xxhash/v2/xxhash_other.go')
-rw-r--r--vendor/github.com/cespare/xxhash/v2/xxhash_other.go76
1 files changed, 76 insertions, 0 deletions
diff --git a/vendor/github.com/cespare/xxhash/v2/xxhash_other.go b/vendor/github.com/cespare/xxhash/v2/xxhash_other.go
new file mode 100644
index 000000000..26df13bba
--- /dev/null
+++ b/vendor/github.com/cespare/xxhash/v2/xxhash_other.go
@@ -0,0 +1,76 @@
+//go:build (!amd64 && !arm64) || appengine || !gc || purego
+// +build !amd64,!arm64 appengine !gc purego
+
+package xxhash
+
+// Sum64 computes the 64-bit xxHash digest of b.
+func Sum64(b []byte) uint64 {
+ // A simpler version would be
+ // d := New()
+ // d.Write(b)
+ // return d.Sum64()
+ // but this is faster, particularly for small inputs.
+
+ n := len(b)
+ var h uint64
+
+ if n >= 32 {
+ v1 := primes[0] + prime2
+ v2 := prime2
+ v3 := uint64(0)
+ v4 := -primes[0]
+ for len(b) >= 32 {
+ v1 = round(v1, u64(b[0:8:len(b)]))
+ v2 = round(v2, u64(b[8:16:len(b)]))
+ v3 = round(v3, u64(b[16:24:len(b)]))
+ v4 = round(v4, u64(b[24:32:len(b)]))
+ b = b[32:len(b):len(b)]
+ }
+ h = rol1(v1) + rol7(v2) + rol12(v3) + rol18(v4)
+ h = mergeRound(h, v1)
+ h = mergeRound(h, v2)
+ h = mergeRound(h, v3)
+ h = mergeRound(h, v4)
+ } else {
+ h = prime5
+ }
+
+ h += uint64(n)
+
+ for ; len(b) >= 8; b = b[8:] {
+ k1 := round(0, u64(b[:8]))
+ h ^= k1
+ h = rol27(h)*prime1 + prime4
+ }
+ if len(b) >= 4 {
+ h ^= uint64(u32(b[:4])) * prime1
+ h = rol23(h)*prime2 + prime3
+ b = b[4:]
+ }
+ for ; len(b) > 0; b = b[1:] {
+ h ^= uint64(b[0]) * prime5
+ h = rol11(h) * prime1
+ }
+
+ h ^= h >> 33
+ h *= prime2
+ h ^= h >> 29
+ h *= prime3
+ h ^= h >> 32
+
+ return h
+}
+
+func writeBlocks(d *Digest, b []byte) int {
+ v1, v2, v3, v4 := d.v1, d.v2, d.v3, d.v4
+ n := len(b)
+ for len(b) >= 32 {
+ v1 = round(v1, u64(b[0:8:len(b)]))
+ v2 = round(v2, u64(b[8:16:len(b)]))
+ v3 = round(v3, u64(b[16:24:len(b)]))
+ v4 = round(v4, u64(b[24:32:len(b)]))
+ b = b[32:len(b):len(b)]
+ }
+ d.v1, d.v2, d.v3, d.v4 = v1, v2, v3, v4
+ return n - len(b)
+}