[Qemu-devel] [RFC 13/48] xxhash: add qemu_xxhash8

[Emilio G. Cota]

It will be used for TB hashing soon.

Signed-off-by: Emilio G. Cota <c...@braap.org>
---
 include/qemu/xxhash.h | 40 +++++++++++++++++++++++++++-------------
 1 file changed, 27 insertions(+), 13 deletions(-)

diff --git a/include/qemu/xxhash.h b/include/qemu/xxhash.h
index fe35dde328..450427eeaa 100644
--- a/include/qemu/xxhash.h
+++ b/include/qemu/xxhash.h
@@ -49,7 +49,8 @@
  * contiguous in memory.
  */
 static inline uint32_t
-qemu_xxhash7(uint64_t ab, uint64_t cd, uint32_t e, uint32_t f, uint32_t g)
+qemu_xxhash8(uint64_t ab, uint64_t cd, uint32_t e, uint32_t f, uint32_t g,
+             uint32_t h)
 {
     uint32_t v1 = QEMU_XXHASH_SEED + PRIME32_1 + PRIME32_2;
     uint32_t v2 = QEMU_XXHASH_SEED + PRIME32_2;
@@ -77,17 +78,24 @@ qemu_xxhash7(uint64_t ab, uint64_t cd, uint32_t e, uint32_t 
f, uint32_t g)
     v4 = rol32(v4, 13);
     v4 *= PRIME32_1;
 
-    h32 = rol32(v1, 1) + rol32(v2, 7) + rol32(v3, 12) + rol32(v4, 18);
-    h32 += 28;
+    v1 += e * PRIME32_2;
+    v1 = rol32(v1, 13);
+    v1 *= PRIME32_1;
 
-    h32 += e * PRIME32_3;
-    h32  = rol32(h32, 17) * PRIME32_4;
+    v2 += f * PRIME32_2;
+    v2 = rol32(v2, 13);
+    v2 *= PRIME32_1;
+
+    v3 += g * PRIME32_2;
+    v3 = rol32(v3, 13);
+    v3 *= PRIME32_1;
 
-    h32 += f * PRIME32_3;
-    h32  = rol32(h32, 17) * PRIME32_4;
+    v4 += h * PRIME32_2;
+    v4 = rol32(v4, 13);
+    v4 *= PRIME32_1;
 
-    h32 += g * PRIME32_3;
-    h32  = rol32(h32, 17) * PRIME32_4;
+    h32 = rol32(v1, 1) + rol32(v2, 7) + rol32(v3, 12) + rol32(v4, 18);
+    h32 += 32;
 
     h32 ^= h32 >> 15;
     h32 *= PRIME32_2;
@@ -100,23 +108,29 @@ qemu_xxhash7(uint64_t ab, uint64_t cd, uint32_t e, 
uint32_t f, uint32_t g)
 
 static inline uint32_t qemu_xxhash2(uint64_t ab)
 {
-    return qemu_xxhash7(ab, 0, 0, 0, 0);
+    return qemu_xxhash8(ab, 0, 0, 0, 0, 0);
 }
 
 static inline uint32_t qemu_xxhash4(uint64_t ab, uint64_t cd)
 {
-    return qemu_xxhash7(ab, cd, 0, 0, 0);
+    return qemu_xxhash8(ab, cd, 0, 0, 0, 0);
 }
 
 static inline uint32_t qemu_xxhash5(uint64_t ab, uint64_t cd, uint32_t e)
 {
-    return qemu_xxhash7(ab, cd, e, 0, 0);
+    return qemu_xxhash8(ab, cd, e, 0, 0, 0);
 }
 
 static inline uint32_t qemu_xxhash6(uint64_t ab, uint64_t cd, uint32_t e,
                                     uint32_t f)
 {
-    return qemu_xxhash7(ab, cd, e, f, 0);
+    return qemu_xxhash8(ab, cd, e, f, 0, 0);
+}
+
+static inline uint32_t qemu_xxhash7(uint64_t ab, uint64_t cd, uint32_t e,
+                                    uint32_t f, uint32_t g)
+{
+    return qemu_xxhash8(ab, cd, e, f, g, 0);
 }
 
 #endif /* QEMU_XXHASH_H */
-- 
2.17.1