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-rw-r--r--src/backend/access/common/tupdesc.c1
-rw-r--r--src/backend/access/hash/hashfunc.c627
-rw-r--r--src/backend/access/tablesample/bernoulli.c2
-rw-r--r--src/backend/access/tablesample/system.c2
4 files changed, 3 insertions, 629 deletions
diff --git a/src/backend/access/common/tupdesc.c b/src/backend/access/common/tupdesc.c
index 832c3e9af6c..0158950a432 100644
--- a/src/backend/access/common/tupdesc.c
+++ b/src/backend/access/common/tupdesc.c
@@ -19,7 +19,6 @@
#include "postgres.h"
-#include "access/hash.h"
#include "access/htup_details.h"
#include "access/tupdesc_details.h"
#include "catalog/pg_collation.h"
diff --git a/src/backend/access/hash/hashfunc.c b/src/backend/access/hash/hashfunc.c
index 63005ddc4df..e5f3d42e045 100644
--- a/src/backend/access/hash/hashfunc.c
+++ b/src/backend/access/hash/hashfunc.c
@@ -28,6 +28,7 @@
#include "access/hash.h"
#include "utils/builtins.h"
+#include "utils/hashutils.h"
/*
* Datatype-specific hash functions.
@@ -307,629 +308,3 @@ hashvarlenaextended(PG_FUNCTION_ARGS)
return result;
}
-
-/*
- * This hash function was written by Bob Jenkins
- * (bob_jenkins@burtleburtle.net), and superficially adapted
- * for PostgreSQL by Neil Conway. For more information on this
- * hash function, see http://burtleburtle.net/bob/hash/doobs.html,
- * or Bob's article in Dr. Dobb's Journal, Sept. 1997.
- *
- * In the current code, we have adopted Bob's 2006 update of his hash
- * function to fetch the data a word at a time when it is suitably aligned.
- * This makes for a useful speedup, at the cost of having to maintain
- * four code paths (aligned vs unaligned, and little-endian vs big-endian).
- * It also uses two separate mixing functions mix() and final(), instead
- * of a slower multi-purpose function.
- */
-
-/* Get a bit mask of the bits set in non-uint32 aligned addresses */
-#define UINT32_ALIGN_MASK (sizeof(uint32) - 1)
-
-/* Rotate a uint32 value left by k bits - note multiple evaluation! */
-#define rot(x,k) (((x)<<(k)) | ((x)>>(32-(k))))
-
-/*----------
- * mix -- mix 3 32-bit values reversibly.
- *
- * This is reversible, so any information in (a,b,c) before mix() is
- * still in (a,b,c) after mix().
- *
- * If four pairs of (a,b,c) inputs are run through mix(), or through
- * mix() in reverse, there are at least 32 bits of the output that
- * are sometimes the same for one pair and different for another pair.
- * This was tested for:
- * * pairs that differed by one bit, by two bits, in any combination
- * of top bits of (a,b,c), or in any combination of bottom bits of
- * (a,b,c).
- * * "differ" is defined as +, -, ^, or ~^. For + and -, I transformed
- * the output delta to a Gray code (a^(a>>1)) so a string of 1's (as
- * is commonly produced by subtraction) look like a single 1-bit
- * difference.
- * * the base values were pseudorandom, all zero but one bit set, or
- * all zero plus a counter that starts at zero.
- *
- * This does not achieve avalanche. There are input bits of (a,b,c)
- * that fail to affect some output bits of (a,b,c), especially of a. The
- * most thoroughly mixed value is c, but it doesn't really even achieve
- * avalanche in c.
- *
- * This allows some parallelism. Read-after-writes are good at doubling
- * the number of bits affected, so the goal of mixing pulls in the opposite
- * direction from the goal of parallelism. I did what I could. Rotates
- * seem to cost as much as shifts on every machine I could lay my hands on,
- * and rotates are much kinder to the top and bottom bits, so I used rotates.
- *----------
- */
-#define mix(a,b,c) \
-{ \
- a -= c; a ^= rot(c, 4); c += b; \
- b -= a; b ^= rot(a, 6); a += c; \
- c -= b; c ^= rot(b, 8); b += a; \
- a -= c; a ^= rot(c,16); c += b; \
- b -= a; b ^= rot(a,19); a += c; \
- c -= b; c ^= rot(b, 4); b += a; \
-}
-
-/*----------
- * final -- final mixing of 3 32-bit values (a,b,c) into c
- *
- * Pairs of (a,b,c) values differing in only a few bits will usually
- * produce values of c that look totally different. This was tested for
- * * pairs that differed by one bit, by two bits, in any combination
- * of top bits of (a,b,c), or in any combination of bottom bits of
- * (a,b,c).
- * * "differ" is defined as +, -, ^, or ~^. For + and -, I transformed
- * the output delta to a Gray code (a^(a>>1)) so a string of 1's (as
- * is commonly produced by subtraction) look like a single 1-bit
- * difference.
- * * the base values were pseudorandom, all zero but one bit set, or
- * all zero plus a counter that starts at zero.
- *
- * The use of separate functions for mix() and final() allow for a
- * substantial performance increase since final() does not need to
- * do well in reverse, but is does need to affect all output bits.
- * mix(), on the other hand, does not need to affect all output
- * bits (affecting 32 bits is enough). The original hash function had
- * a single mixing operation that had to satisfy both sets of requirements
- * and was slower as a result.
- *----------
- */
-#define final(a,b,c) \
-{ \
- c ^= b; c -= rot(b,14); \
- a ^= c; a -= rot(c,11); \
- b ^= a; b -= rot(a,25); \
- c ^= b; c -= rot(b,16); \
- a ^= c; a -= rot(c, 4); \
- b ^= a; b -= rot(a,14); \
- c ^= b; c -= rot(b,24); \
-}
-
-/*
- * hash_any() -- hash a variable-length key into a 32-bit value
- * k : the key (the unaligned variable-length array of bytes)
- * len : the length of the key, counting by bytes
- *
- * Returns a uint32 value. Every bit of the key affects every bit of
- * the return value. Every 1-bit and 2-bit delta achieves avalanche.
- * About 6*len+35 instructions. The best hash table sizes are powers
- * of 2. There is no need to do mod a prime (mod is sooo slow!).
- * If you need less than 32 bits, use a bitmask.
- *
- * This procedure must never throw elog(ERROR); the ResourceOwner code
- * relies on this not to fail.
- *
- * Note: we could easily change this function to return a 64-bit hash value
- * by using the final values of both b and c. b is perhaps a little less
- * well mixed than c, however.
- */
-Datum
-hash_any(register const unsigned char *k, register int keylen)
-{
- register uint32 a,
- b,
- c,
- len;
-
- /* Set up the internal state */
- len = keylen;
- a = b = c = 0x9e3779b9 + len + 3923095;
-
- /* If the source pointer is word-aligned, we use word-wide fetches */
- if (((uintptr_t) k & UINT32_ALIGN_MASK) == 0)
- {
- /* Code path for aligned source data */
- register const uint32 *ka = (const uint32 *) k;
-
- /* handle most of the key */
- while (len >= 12)
- {
- a += ka[0];
- b += ka[1];
- c += ka[2];
- mix(a, b, c);
- ka += 3;
- len -= 12;
- }
-
- /* handle the last 11 bytes */
- k = (const unsigned char *) ka;
-#ifdef WORDS_BIGENDIAN
- switch (len)
- {
- case 11:
- c += ((uint32) k[10] << 8);
- /* fall through */
- case 10:
- c += ((uint32) k[9] << 16);
- /* fall through */
- case 9:
- c += ((uint32) k[8] << 24);
- /* fall through */
- case 8:
- /* the lowest byte of c is reserved for the length */
- b += ka[1];
- a += ka[0];
- break;
- case 7:
- b += ((uint32) k[6] << 8);
- /* fall through */
- case 6:
- b += ((uint32) k[5] << 16);
- /* fall through */
- case 5:
- b += ((uint32) k[4] << 24);
- /* fall through */
- case 4:
- a += ka[0];
- break;
- case 3:
- a += ((uint32) k[2] << 8);
- /* fall through */
- case 2:
- a += ((uint32) k[1] << 16);
- /* fall through */
- case 1:
- a += ((uint32) k[0] << 24);
- /* case 0: nothing left to add */
- }
-#else /* !WORDS_BIGENDIAN */
- switch (len)
- {
- case 11:
- c += ((uint32) k[10] << 24);
- /* fall through */
- case 10:
- c += ((uint32) k[9] << 16);
- /* fall through */
- case 9:
- c += ((uint32) k[8] << 8);
- /* fall through */
- case 8:
- /* the lowest byte of c is reserved for the length */
- b += ka[1];
- a += ka[0];
- break;
- case 7:
- b += ((uint32) k[6] << 16);
- /* fall through */
- case 6:
- b += ((uint32) k[5] << 8);
- /* fall through */
- case 5:
- b += k[4];
- /* fall through */
- case 4:
- a += ka[0];
- break;
- case 3:
- a += ((uint32) k[2] << 16);
- /* fall through */
- case 2:
- a += ((uint32) k[1] << 8);
- /* fall through */
- case 1:
- a += k[0];
- /* case 0: nothing left to add */
- }
-#endif /* WORDS_BIGENDIAN */
- }
- else
- {
- /* Code path for non-aligned source data */
-
- /* handle most of the key */
- while (len >= 12)
- {
-#ifdef WORDS_BIGENDIAN
- a += (k[3] + ((uint32) k[2] << 8) + ((uint32) k[1] << 16) + ((uint32) k[0] << 24));
- b += (k[7] + ((uint32) k[6] << 8) + ((uint32) k[5] << 16) + ((uint32) k[4] << 24));
- c += (k[11] + ((uint32) k[10] << 8) + ((uint32) k[9] << 16) + ((uint32) k[8] << 24));
-#else /* !WORDS_BIGENDIAN */
- a += (k[0] + ((uint32) k[1] << 8) + ((uint32) k[2] << 16) + ((uint32) k[3] << 24));
- b += (k[4] + ((uint32) k[5] << 8) + ((uint32) k[6] << 16) + ((uint32) k[7] << 24));
- c += (k[8] + ((uint32) k[9] << 8) + ((uint32) k[10] << 16) + ((uint32) k[11] << 24));
-#endif /* WORDS_BIGENDIAN */
- mix(a, b, c);
- k += 12;
- len -= 12;
- }
-
- /* handle the last 11 bytes */
-#ifdef WORDS_BIGENDIAN
- switch (len)
- {
- case 11:
- c += ((uint32) k[10] << 8);
- /* fall through */
- case 10:
- c += ((uint32) k[9] << 16);
- /* fall through */
- case 9:
- c += ((uint32) k[8] << 24);
- /* fall through */
- case 8:
- /* the lowest byte of c is reserved for the length */
- b += k[7];
- /* fall through */
- case 7:
- b += ((uint32) k[6] << 8);
- /* fall through */
- case 6:
- b += ((uint32) k[5] << 16);
- /* fall through */
- case 5:
- b += ((uint32) k[4] << 24);
- /* fall through */
- case 4:
- a += k[3];
- /* fall through */
- case 3:
- a += ((uint32) k[2] << 8);
- /* fall through */
- case 2:
- a += ((uint32) k[1] << 16);
- /* fall through */
- case 1:
- a += ((uint32) k[0] << 24);
- /* case 0: nothing left to add */
- }
-#else /* !WORDS_BIGENDIAN */
- switch (len)
- {
- case 11:
- c += ((uint32) k[10] << 24);
- /* fall through */
- case 10:
- c += ((uint32) k[9] << 16);
- /* fall through */
- case 9:
- c += ((uint32) k[8] << 8);
- /* fall through */
- case 8:
- /* the lowest byte of c is reserved for the length */
- b += ((uint32) k[7] << 24);
- /* fall through */
- case 7:
- b += ((uint32) k[6] << 16);
- /* fall through */
- case 6:
- b += ((uint32) k[5] << 8);
- /* fall through */
- case 5:
- b += k[4];
- /* fall through */
- case 4:
- a += ((uint32) k[3] << 24);
- /* fall through */
- case 3:
- a += ((uint32) k[2] << 16);
- /* fall through */
- case 2:
- a += ((uint32) k[1] << 8);
- /* fall through */
- case 1:
- a += k[0];
- /* case 0: nothing left to add */
- }
-#endif /* WORDS_BIGENDIAN */
- }
-
- final(a, b, c);
-
- /* report the result */
- return UInt32GetDatum(c);
-}
-
-/*
- * hash_any_extended() -- hash into a 64-bit value, using an optional seed
- * k : the key (the unaligned variable-length array of bytes)
- * len : the length of the key, counting by bytes
- * seed : a 64-bit seed (0 means no seed)
- *
- * Returns a uint64 value. Otherwise similar to hash_any.
- */
-Datum
-hash_any_extended(register const unsigned char *k, register int keylen,
- uint64 seed)
-{
- register uint32 a,
- b,
- c,
- len;
-
- /* Set up the internal state */
- len = keylen;
- a = b = c = 0x9e3779b9 + len + 3923095;
-
- /* If the seed is non-zero, use it to perturb the internal state. */
- if (seed != 0)
- {
- /*
- * In essence, the seed is treated as part of the data being hashed,
- * but for simplicity, we pretend that it's padded with four bytes of
- * zeroes so that the seed constitutes a 12-byte chunk.
- */
- a += (uint32) (seed >> 32);
- b += (uint32) seed;
- mix(a, b, c);
- }
-
- /* If the source pointer is word-aligned, we use word-wide fetches */
- if (((uintptr_t) k & UINT32_ALIGN_MASK) == 0)
- {
- /* Code path for aligned source data */
- register const uint32 *ka = (const uint32 *) k;
-
- /* handle most of the key */
- while (len >= 12)
- {
- a += ka[0];
- b += ka[1];
- c += ka[2];
- mix(a, b, c);
- ka += 3;
- len -= 12;
- }
-
- /* handle the last 11 bytes */
- k = (const unsigned char *) ka;
-#ifdef WORDS_BIGENDIAN
- switch (len)
- {
- case 11:
- c += ((uint32) k[10] << 8);
- /* fall through */
- case 10:
- c += ((uint32) k[9] << 16);
- /* fall through */
- case 9:
- c += ((uint32) k[8] << 24);
- /* fall through */
- case 8:
- /* the lowest byte of c is reserved for the length */
- b += ka[1];
- a += ka[0];
- break;
- case 7:
- b += ((uint32) k[6] << 8);
- /* fall through */
- case 6:
- b += ((uint32) k[5] << 16);
- /* fall through */
- case 5:
- b += ((uint32) k[4] << 24);
- /* fall through */
- case 4:
- a += ka[0];
- break;
- case 3:
- a += ((uint32) k[2] << 8);
- /* fall through */
- case 2:
- a += ((uint32) k[1] << 16);
- /* fall through */
- case 1:
- a += ((uint32) k[0] << 24);
- /* case 0: nothing left to add */
- }
-#else /* !WORDS_BIGENDIAN */
- switch (len)
- {
- case 11:
- c += ((uint32) k[10] << 24);
- /* fall through */
- case 10:
- c += ((uint32) k[9] << 16);
- /* fall through */
- case 9:
- c += ((uint32) k[8] << 8);
- /* fall through */
- case 8:
- /* the lowest byte of c is reserved for the length */
- b += ka[1];
- a += ka[0];
- break;
- case 7:
- b += ((uint32) k[6] << 16);
- /* fall through */
- case 6:
- b += ((uint32) k[5] << 8);
- /* fall through */
- case 5:
- b += k[4];
- /* fall through */
- case 4:
- a += ka[0];
- break;
- case 3:
- a += ((uint32) k[2] << 16);
- /* fall through */
- case 2:
- a += ((uint32) k[1] << 8);
- /* fall through */
- case 1:
- a += k[0];
- /* case 0: nothing left to add */
- }
-#endif /* WORDS_BIGENDIAN */
- }
- else
- {
- /* Code path for non-aligned source data */
-
- /* handle most of the key */
- while (len >= 12)
- {
-#ifdef WORDS_BIGENDIAN
- a += (k[3] + ((uint32) k[2] << 8) + ((uint32) k[1] << 16) + ((uint32) k[0] << 24));
- b += (k[7] + ((uint32) k[6] << 8) + ((uint32) k[5] << 16) + ((uint32) k[4] << 24));
- c += (k[11] + ((uint32) k[10] << 8) + ((uint32) k[9] << 16) + ((uint32) k[8] << 24));
-#else /* !WORDS_BIGENDIAN */
- a += (k[0] + ((uint32) k[1] << 8) + ((uint32) k[2] << 16) + ((uint32) k[3] << 24));
- b += (k[4] + ((uint32) k[5] << 8) + ((uint32) k[6] << 16) + ((uint32) k[7] << 24));
- c += (k[8] + ((uint32) k[9] << 8) + ((uint32) k[10] << 16) + ((uint32) k[11] << 24));
-#endif /* WORDS_BIGENDIAN */
- mix(a, b, c);
- k += 12;
- len -= 12;
- }
-
- /* handle the last 11 bytes */
-#ifdef WORDS_BIGENDIAN
- switch (len)
- {
- case 11:
- c += ((uint32) k[10] << 8);
- /* fall through */
- case 10:
- c += ((uint32) k[9] << 16);
- /* fall through */
- case 9:
- c += ((uint32) k[8] << 24);
- /* fall through */
- case 8:
- /* the lowest byte of c is reserved for the length */
- b += k[7];
- /* fall through */
- case 7:
- b += ((uint32) k[6] << 8);
- /* fall through */
- case 6:
- b += ((uint32) k[5] << 16);
- /* fall through */
- case 5:
- b += ((uint32) k[4] << 24);
- /* fall through */
- case 4:
- a += k[3];
- /* fall through */
- case 3:
- a += ((uint32) k[2] << 8);
- /* fall through */
- case 2:
- a += ((uint32) k[1] << 16);
- /* fall through */
- case 1:
- a += ((uint32) k[0] << 24);
- /* case 0: nothing left to add */
- }
-#else /* !WORDS_BIGENDIAN */
- switch (len)
- {
- case 11:
- c += ((uint32) k[10] << 24);
- /* fall through */
- case 10:
- c += ((uint32) k[9] << 16);
- /* fall through */
- case 9:
- c += ((uint32) k[8] << 8);
- /* fall through */
- case 8:
- /* the lowest byte of c is reserved for the length */
- b += ((uint32) k[7] << 24);
- /* fall through */
- case 7:
- b += ((uint32) k[6] << 16);
- /* fall through */
- case 6:
- b += ((uint32) k[5] << 8);
- /* fall through */
- case 5:
- b += k[4];
- /* fall through */
- case 4:
- a += ((uint32) k[3] << 24);
- /* fall through */
- case 3:
- a += ((uint32) k[2] << 16);
- /* fall through */
- case 2:
- a += ((uint32) k[1] << 8);
- /* fall through */
- case 1:
- a += k[0];
- /* case 0: nothing left to add */
- }
-#endif /* WORDS_BIGENDIAN */
- }
-
- final(a, b, c);
-
- /* report the result */
- PG_RETURN_UINT64(((uint64) b << 32) | c);
-}
-
-/*
- * hash_uint32() -- hash a 32-bit value to a 32-bit value
- *
- * This has the same result as
- * hash_any(&k, sizeof(uint32))
- * but is faster and doesn't force the caller to store k into memory.
- */
-Datum
-hash_uint32(uint32 k)
-{
- register uint32 a,
- b,
- c;
-
- a = b = c = 0x9e3779b9 + (uint32) sizeof(uint32) + 3923095;
- a += k;
-
- final(a, b, c);
-
- /* report the result */
- return UInt32GetDatum(c);
-}
-
-/*
- * hash_uint32_extended() -- hash a 32-bit value to a 64-bit value, with a seed
- *
- * Like hash_uint32, this is a convenience function.
- */
-Datum
-hash_uint32_extended(uint32 k, uint64 seed)
-{
- register uint32 a,
- b,
- c;
-
- a = b = c = 0x9e3779b9 + (uint32) sizeof(uint32) + 3923095;
-
- if (seed != 0)
- {
- a += (uint32) (seed >> 32);
- b += (uint32) seed;
- mix(a, b, c);
- }
-
- a += k;
-
- final(a, b, c);
-
- /* report the result */
- PG_RETURN_UINT64(((uint64) b << 32) | c);
-}
diff --git a/src/backend/access/tablesample/bernoulli.c b/src/backend/access/tablesample/bernoulli.c
index 9360b5bbc99..42d373ab83b 100644
--- a/src/backend/access/tablesample/bernoulli.c
+++ b/src/backend/access/tablesample/bernoulli.c
@@ -26,11 +26,11 @@
#include <math.h>
-#include "access/hash.h"
#include "access/tsmapi.h"
#include "catalog/pg_type.h"
#include "optimizer/optimizer.h"
#include "utils/builtins.h"
+#include "utils/hashutils.h"
/* Private state */
diff --git a/src/backend/access/tablesample/system.c b/src/backend/access/tablesample/system.c
index 298e0ab4a09..fb1a5634244 100644
--- a/src/backend/access/tablesample/system.c
+++ b/src/backend/access/tablesample/system.c
@@ -26,13 +26,13 @@
#include <math.h>
-#include "access/hash.h"
#include "access/heapam.h"
#include "access/relscan.h"
#include "access/tsmapi.h"
#include "catalog/pg_type.h"
#include "optimizer/optimizer.h"
#include "utils/builtins.h"
+#include "utils/hashutils.h"
/* Private state */
generated by cgit v1.2.3 (git 2.25.1) at 2025-08-05 14:19:45 +0000