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| author | antirez <antirez@gmail.com> | 2017-02-20 17:32:46 +0100 |
|---|---|---|
| committer | antirez <antirez@gmail.com> | 2017-02-20 17:32:46 +0100 |
| commit | 05ea8c612238bc8b9a8eda2427d6cf8a3afb4ac5 (patch) | |
| tree | 1baa5ff4bac4fd28f009d628c56e40471a86ad0f | |
| parent | adeed29a99dcd0efdbfe4dbd5da74e7b01966c67 (diff) | |
| download | redis-05ea8c612238bc8b9a8eda2427d6cf8a3afb4ac5.tar.gz | |
SipHash x86 optimizations.
| -rw-r--r-- | src/siphash.c | 25 |
1 files changed, 23 insertions, 2 deletions
diff --git a/src/siphash.c b/src/siphash.c index 04e571fd7..3bcada728 100644 --- a/src/siphash.c +++ b/src/siphash.c @@ -40,6 +40,13 @@ #include <string.h> #include <ctype.h> +/* Test of the CPU is Little Endian and supports not aligned accesses. + * Two interesting conditions to speedup the function that happen to be + * in most of x86 servers. */ +#if defined(__X86_64__) || defined(__x86_64__) || defined (__i386__) +#define UNALIGNED_LE_CPU +#endif + #define ROTL(x, b) (uint64_t)(((x) << (b)) | ((x) >> (64 - (b)))) #define U32TO8_LE(p, v) \ @@ -52,11 +59,15 @@ U32TO8_LE((p), (uint32_t)((v))); \ U32TO8_LE((p) + 4, (uint32_t)((v) >> 32)); +#ifdef UNALIGNED_LE_CPU +#define U8TO64_LE(p) (*((uint64_t*)(p))) +#else #define U8TO64_LE(p) \ (((uint64_t)((p)[0])) | ((uint64_t)((p)[1]) << 8) | \ ((uint64_t)((p)[2]) << 16) | ((uint64_t)((p)[3]) << 24) | \ ((uint64_t)((p)[4]) << 32) | ((uint64_t)((p)[5]) << 40) | \ ((uint64_t)((p)[6]) << 48) | ((uint64_t)((p)[7]) << 56)) +#endif #define U8TO64_LE_NOCASE(p) \ (((uint64_t)(tolower((p)[0]))) | \ @@ -87,8 +98,10 @@ } while (0) uint64_t siphash(const uint8_t *in, const size_t inlen, const uint8_t *k) { +#ifndef UNALIGNED_LE_CPU uint64_t hash; uint8_t *out = (uint8_t*) &hash; +#endif uint64_t v0 = 0x736f6d6570736575ULL; uint64_t v1 = 0x646f72616e646f6dULL; uint64_t v2 = 0x6c7967656e657261ULL; @@ -139,15 +152,20 @@ uint64_t siphash(const uint8_t *in, const size_t inlen, const uint8_t *k) { SIPROUND; b = v0 ^ v1 ^ v2 ^ v3; +#ifndef UNALIGNED_LE_CPU U64TO8_LE(out, b); - return hash; +#else + return b; +#endif } uint64_t siphash_nocase(const uint8_t *in, const size_t inlen, const uint8_t *k) { +#ifndef UNALIGNED_LE_CPU uint64_t hash; uint8_t *out = (uint8_t*) &hash; +#endif uint64_t v0 = 0x736f6d6570736575ULL; uint64_t v1 = 0x646f72616e646f6dULL; uint64_t v2 = 0x6c7967656e657261ULL; @@ -198,9 +216,12 @@ uint64_t siphash_nocase(const uint8_t *in, const size_t inlen, const uint8_t *k) SIPROUND; b = v0 ^ v1 ^ v2 ^ v3; +#ifndef UNALIGNED_LE_CPU U64TO8_LE(out, b); - return hash; +#else + return b; +#endif } |