diff options
Diffstat (limited to 'src/backend/utils/adt/mac.c')
| -rw-r--r-- | src/backend/utils/adt/mac.c | 27 |
1 files changed, 10 insertions, 17 deletions
diff --git a/src/backend/utils/adt/mac.c b/src/backend/utils/adt/mac.c index 3644e9735f5..bb38ef2f5e4 100644 --- a/src/backend/utils/adt/mac.c +++ b/src/backend/utils/adt/mac.c @@ -481,33 +481,26 @@ macaddr_abbrev_convert(Datum original, SortSupport ssup) Datum res; /* - * On a 64-bit machine, zero out the 8-byte datum and copy the 6 bytes of - * the MAC address in. There will be two bytes of zero padding on the end - * of the least significant bits. + * Zero out the 8-byte Datum and copy in the 6 bytes of the MAC address. + * There will be two bytes of zero padding on the end of the least + * significant bits. */ -#if SIZEOF_DATUM == 8 - memset(&res, 0, SIZEOF_DATUM); + StaticAssertStmt(sizeof(res) >= sizeof(macaddr), + "Datum is too small for macaddr"); + memset(&res, 0, sizeof(res)); memcpy(&res, authoritative, sizeof(macaddr)); -#else /* SIZEOF_DATUM != 8 */ - memcpy(&res, authoritative, SIZEOF_DATUM); -#endif uss->input_count += 1; /* - * Cardinality estimation. The estimate uses uint32, so on a 64-bit - * architecture, XOR the two 32-bit halves together to produce slightly - * more entropy. The two zeroed bytes won't have any practical impact on - * this operation. + * Cardinality estimation. The estimate uses uint32, so XOR the two 32-bit + * halves together to produce slightly more entropy. The two zeroed bytes + * won't have any practical impact on this operation. */ if (uss->estimating) { uint32 tmp; -#if SIZEOF_DATUM == 8 - tmp = (uint32) res ^ (uint32) ((uint64) res >> 32); -#else /* SIZEOF_DATUM != 8 */ - tmp = (uint32) res; -#endif + tmp = DatumGetUInt32(res) ^ (uint32) (DatumGetUInt64(res) >> 32); addHyperLogLog(&uss->abbr_card, DatumGetUInt32(hash_uint32(tmp))); } |