Code review for improved-hashing patch. Fix some portability issues
(char != unsigned char, Datum != uint32); make use of new hash code in dynahash hash tables and hash joins.
This commit is contained in:
Tom Lane
parent
1eb31d197d
commit
c422b5ca6b
@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/access/hash/hash.c,v 1.55 2002/03/06 20:49:37 momjian Exp $
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* $Header: /cvsroot/pgsql/src/backend/access/hash/hash.c,v 1.56 2002/03/09 17:35:35 tgl Exp $
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*
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* NOTES
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* This file contains only the public interface routines.
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@ -164,6 +164,9 @@ hashinsert(PG_FUNCTION_ARGS)
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Datum *datum = (Datum *) PG_GETARG_POINTER(1);
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char *nulls = (char *) PG_GETARG_POINTER(2);
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ItemPointer ht_ctid = (ItemPointer) PG_GETARG_POINTER(3);
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#ifdef NOT_USED
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Relation heapRel = (Relation) PG_GETARG_POINTER(4);
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#endif
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InsertIndexResult res;
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HashItem hitem;
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/access/hash/hashfunc.c,v 1.32 2002/03/06 20:49:38 momjian Exp $
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* $Header: /cvsroot/pgsql/src/backend/access/hash/hashfunc.c,v 1.33 2002/03/09 17:35:35 tgl Exp $
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*
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* NOTES
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* These functions are stored in pg_amproc. For each operator class
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@ -58,7 +58,7 @@ hashfloat4(PG_FUNCTION_ARGS)
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{
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float4 key = PG_GETARG_FLOAT4(0);
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return hash_any((char *) &key, sizeof(key));
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return hash_any((unsigned char *) &key, sizeof(key));
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}
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Datum
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@ -66,7 +66,7 @@ hashfloat8(PG_FUNCTION_ARGS)
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{
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float8 key = PG_GETARG_FLOAT8(0);
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return hash_any((char *) &key, sizeof(key));
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return hash_any((unsigned char *) &key, sizeof(key));
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}
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Datum
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@ -74,7 +74,7 @@ hashoidvector(PG_FUNCTION_ARGS)
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{
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Oid *key = (Oid *) PG_GETARG_POINTER(0);
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return hash_any((char *) key, INDEX_MAX_KEYS * sizeof(Oid));
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return hash_any((unsigned char *) key, INDEX_MAX_KEYS * sizeof(Oid));
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}
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/*
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@ -87,17 +87,18 @@ hashint2vector(PG_FUNCTION_ARGS)
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{
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int16 *key = (int16 *) PG_GETARG_POINTER(0);
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return hash_any((char *) key, INDEX_MAX_KEYS * sizeof(int16));
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return hash_any((unsigned char *) key, INDEX_MAX_KEYS * sizeof(int16));
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}
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Datum
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hashname(PG_FUNCTION_ARGS)
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{
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char *key = NameStr(*PG_GETARG_NAME(0));
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int keylen = strlen(key);
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Assert(strlen(key) <= NAMEDATALEN);
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Assert(keylen < NAMEDATALEN); /* else it's not truncated correctly */
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return hash_any(key, strlen(key));
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return hash_any((unsigned char *) key, keylen);
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}
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/*
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@ -110,7 +111,8 @@ hashvarlena(PG_FUNCTION_ARGS)
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struct varlena *key = PG_GETARG_VARLENA_P(0);
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Datum result;
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result = hash_any(VARDATA(key), VARSIZE(key) - VARHDRSZ);
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result = hash_any((unsigned char *) VARDATA(key),
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VARSIZE(key) - VARHDRSZ);
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/* Avoid leaking memory for toasted inputs */
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PG_FREE_IF_COPY(key, 0);
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@ -118,13 +120,15 @@ hashvarlena(PG_FUNCTION_ARGS)
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return result;
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}
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/* This hash function was written by Bob Jenkins
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/*
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* This hash function was written by Bob Jenkins
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* (bob_jenkins@burtleburtle.net), and superficially adapted
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* for PostgreSQL by Neil Conway. For more information on this
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* hash function, see http://burtleburtle.net/bob/hash/doobs.html
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* hash function, see http://burtleburtle.net/bob/hash/doobs.html,
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* or Bob's article in Dr. Dobb's Journal, Sept. 1997.
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*/
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/*
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/*----------
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* mix -- mix 3 32-bit values reversibly.
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* For every delta with one or two bits set, and the deltas of all three
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* high bits or all three low bits, whether the original value of a,b,c
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@ -133,6 +137,7 @@ hashvarlena(PG_FUNCTION_ARGS)
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* have at least 1/4 probability of changing.
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* - If mix() is run forward, every bit of c will change between 1/3 and
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* 2/3 of the time. (Well, 22/100 and 78/100 for some 2-bit deltas.)
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*----------
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*/
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#define mix(a,b,c) \
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{ \
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@ -151,56 +156,52 @@ hashvarlena(PG_FUNCTION_ARGS)
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* hash_any() -- hash a variable-length key into a 32-bit value
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* k : the key (the unaligned variable-length array of bytes)
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* len : the length of the key, counting by bytes
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* Returns a 32-bit value. Every bit of the key affects every bit of
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*
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* Returns a uint32 value. Every bit of the key affects every bit of
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* the return value. Every 1-bit and 2-bit delta achieves avalanche.
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* About 6*len+35 instructions. The best hash table sizes are powers
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* of 2. There is no need to do mod a prime (mod is sooo slow!).
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* If you need less than 32 bits, use a bitmask.
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*/
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Datum
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hash_any(register const char *k, register int keylen)
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hash_any(register const unsigned char *k, register int keylen)
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{
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register Datum a,b,c,len;
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register uint32 a,b,c,len;
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/* Set up the internal state */
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len = keylen;
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a = b = 0x9e3779b9; /* the golden ratio; an arbitrary value */
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/* Another arbitrary value. If the hash function is called
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* multiple times, this could be the previously generated
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* hash value; however, the interface currently doesn't allow
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* this. AFAIK this isn't a big deal.
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*/
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c = 3923095;
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/* Set up the internal state */
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len = keylen;
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a = b = 0x9e3779b9; /* the golden ratio; an arbitrary value */
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c = 3923095; /* initialize with an arbitrary value */
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/* handle most of the key */
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while (len >= 12)
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{
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a += (k[0] +((Datum)k[1]<<8) +((Datum)k[2]<<16) +((Datum)k[3]<<24));
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b += (k[4] +((Datum)k[5]<<8) +((Datum)k[6]<<16) +((Datum)k[7]<<24));
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c += (k[8] +((Datum)k[9]<<8) +((Datum)k[10]<<16)+((Datum)k[11]<<24));
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mix(a,b,c);
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k += 12; len -= 12;
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}
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/* handle most of the key */
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while (len >= 12)
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{
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a += (k[0] +((uint32)k[1]<<8) +((uint32)k[2]<<16) +((uint32)k[3]<<24));
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b += (k[4] +((uint32)k[5]<<8) +((uint32)k[6]<<16) +((uint32)k[7]<<24));
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c += (k[8] +((uint32)k[9]<<8) +((uint32)k[10]<<16)+((uint32)k[11]<<24));
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mix(a,b,c);
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k += 12; len -= 12;
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}
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/* handle the last 11 bytes */
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c += keylen;
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switch(len) /* all the case statements fall through */
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{
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case 11: c+=((Datum)k[10]<<24);
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case 10: c+=((Datum)k[9]<<16);
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case 9 : c+=((Datum)k[8]<<8);
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/* the first byte of c is reserved for the length */
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case 8 : b+=((Datum)k[7]<<24);
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case 7 : b+=((Datum)k[6]<<16);
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case 6 : b+=((Datum)k[5]<<8);
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case 5 : b+=k[4];
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case 4 : a+=((Datum)k[3]<<24);
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case 3 : a+=((Datum)k[2]<<16);
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case 2 : a+=((Datum)k[1]<<8);
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case 1 : a+=k[0];
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/* case 0: nothing left to add */
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}
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mix(a,b,c);
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/* report the result */
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return c;
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/* handle the last 11 bytes */
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c += keylen;
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switch (len) /* all the case statements fall through */
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{
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case 11: c+=((uint32)k[10]<<24);
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case 10: c+=((uint32)k[9]<<16);
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case 9 : c+=((uint32)k[8]<<8);
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/* the first byte of c is reserved for the length */
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case 8 : b+=((uint32)k[7]<<24);
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case 7 : b+=((uint32)k[6]<<16);
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case 6 : b+=((uint32)k[5]<<8);
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case 5 : b+=k[4];
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case 4 : a+=((uint32)k[3]<<24);
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case 3 : a+=((uint32)k[2]<<16);
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case 2 : a+=((uint32)k[1]<<8);
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case 1 : a+=k[0];
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/* case 0: nothing left to add */
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}
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mix(a,b,c);
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/* report the result */
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return UInt32GetDatum(c);
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}
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@ -7,7 +7,7 @@
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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*
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* $Id: nodeHash.c,v 1.61 2002/03/06 20:49:44 momjian Exp $
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* $Id: nodeHash.c,v 1.62 2002/03/09 17:35:35 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -22,6 +22,7 @@
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#include <sys/types.h>
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#include <math.h>
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#include "access/hash.h"
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#include "executor/execdebug.h"
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#include "executor/nodeHash.h"
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#include "executor/nodeHashjoin.h"
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@ -31,7 +32,7 @@
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#include "utils/lsyscache.h"
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static int hashFunc(Datum key, int len, bool byVal);
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static uint32 hashFunc(Datum key, int len, bool byVal);
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/* ----------------------------------------------------------------
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* ExecHash
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@ -553,7 +554,7 @@ ExecHashGetBucket(HashJoinTable hashtable,
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bucketno = hashFunc(keyval,
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(int) hashtable->typLen,
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hashtable->typByVal)
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% hashtable->totalbuckets;
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% (uint32) hashtable->totalbuckets;
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}
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#ifdef HJDEBUG
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@ -624,30 +625,29 @@ ExecScanHashBucket(HashJoinState *hjstate,
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/* ----------------------------------------------------------------
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* hashFunc
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*
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* the hash function, copied from Margo
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* the hash function for hash joins
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*
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* XXX this probably ought to be replaced with datatype-specific
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* hash functions, such as those already implemented for hash indexes.
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* ----------------------------------------------------------------
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*/
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static int
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static uint32
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hashFunc(Datum key, int len, bool byVal)
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{
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unsigned int h = 0;
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unsigned char *k;
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if (byVal)
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{
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/*
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* If it's a by-value data type, use the 'len' least significant
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* bytes of the Datum value. This should do the right thing on
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* either bigendian or littleendian hardware --- see the Datum
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* access macros in c.h.
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* If it's a by-value data type, just hash the whole Datum value.
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* This assumes that datatypes narrower than Datum are consistently
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* padded (either zero-extended or sign-extended, but not random
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* bits) to fill Datum; see the XXXGetDatum macros in postgres.h.
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* NOTE: it would not work to do hash_any(&key, len) since this
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* would get the wrong bytes on a big-endian machine.
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*/
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while (len-- > 0)
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{
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h = (h * PRIME1) ^ (key & 0xFF);
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key >>= 8;
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}
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k = (unsigned char *) &key;
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len = sizeof(Datum);
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}
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else
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{
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@ -662,8 +662,6 @@ hashFunc(Datum key, int len, bool byVal)
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* freeing the detoasted copy; that happens for free when the
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* per-tuple memory context is reset in ExecHashGetBucket.)
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*/
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unsigned char *k;
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if (len < 0)
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{
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struct varlena *vkey = PG_DETOAST_DATUM(key);
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@ -673,12 +671,9 @@ hashFunc(Datum key, int len, bool byVal)
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}
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else
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k = (unsigned char *) DatumGetPointer(key);
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while (len-- > 0)
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h = (h * PRIME1) ^ (*k++);
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}
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return h % PRIME2;
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return DatumGetUInt32(hash_any(k, len));
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}
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/* ----------------------------------------------------------------
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/utils/adt/date.c,v 1.64 2001/11/21 05:57:33 thomas Exp $
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* $Header: /cvsroot/pgsql/src/backend/utils/adt/date.c,v 1.65 2002/03/09 17:35:35 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -1116,7 +1116,7 @@ timetz_hash(PG_FUNCTION_ARGS)
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* sizeof(TimeTzADT), so that any garbage pad bytes in the structure
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* won't be included in the hash!
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*/
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return hash_any((char *) key, sizeof(double) + sizeof(int4));
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return hash_any((unsigned char *) key, sizeof(double) + sizeof(int4));
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}
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Datum
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@ -1,7 +1,7 @@
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/*
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* PostgreSQL type definitions for MAC addresses.
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*
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* $Header: /cvsroot/pgsql/src/backend/utils/adt/mac.c,v 1.21 2001/08/21 21:23:21 tgl Exp $
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* $Header: /cvsroot/pgsql/src/backend/utils/adt/mac.c,v 1.22 2002/03/09 17:35:35 tgl Exp $
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*/
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#include "postgres.h"
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@ -230,7 +230,7 @@ hashmacaddr(PG_FUNCTION_ARGS)
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{
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macaddr *key = PG_GETARG_MACADDR_P(0);
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return hash_any((char *) key, sizeof(macaddr));
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return hash_any((unsigned char *) key, sizeof(macaddr));
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}
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/*
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/utils/adt/timestamp.c,v 1.64 2002/03/06 06:10:18 momjian Exp $
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* $Header: /cvsroot/pgsql/src/backend/utils/adt/timestamp.c,v 1.65 2002/03/09 17:35:36 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -1017,7 +1017,7 @@ interval_hash(PG_FUNCTION_ARGS)
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* sizeof(Interval), so that any garbage pad bytes in the structure
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* won't be included in the hash!
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*/
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return hash_any((char *) key, sizeof(double) + sizeof(int4));
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return hash_any((unsigned char *) key, sizeof(double) + sizeof(int4));
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}
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/* overlaps_timestamp() --- implements the SQL92 OVERLAPS operator.
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/utils/adt/varchar.c,v 1.87 2001/11/18 12:07:07 ishii Exp $
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* $Header: /cvsroot/pgsql/src/backend/utils/adt/varchar.c,v 1.88 2002/03/09 17:35:36 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -791,7 +791,7 @@ hashbpchar(PG_FUNCTION_ARGS)
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keydata = VARDATA(key);
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keylen = bcTruelen(key);
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result = hash_any(keydata, keylen);
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result = hash_any((unsigned char *) keydata, keylen);
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/* Avoid leaking memory for toasted inputs */
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PG_FREE_IF_COPY(key, 0);
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@ -9,7 +9,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/utils/hash/dynahash.c,v 1.41 2002/03/02 21:39:33 momjian Exp $
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* $Header: /cvsroot/pgsql/src/backend/utils/hash/dynahash.c,v 1.42 2002/03/09 17:35:36 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -329,8 +329,7 @@ init_htab(HTAB *hashp, long nelem)
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}
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#if HASH_DEBUG
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fprintf(stderr, "%s\n%s%p\n%s%d\n%s%d\n%s%d\n%s%d\n%s%d\n%s%x\n%s%x\n%s%d\n%s%d\n",
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"init_htab:",
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fprintf(stderr, "init_htab:\n%s%p\n%s%ld\n%s%ld\n%s%d\n%s%ld\n%s%u\n%s%x\n%s%x\n%s%ld\n%s%ld\n",
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"TABLE POINTER ", hashp,
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"DIRECTORY SIZE ", hctl->dsize,
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"SEGMENT SIZE ", hctl->ssize,
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@ -453,7 +452,7 @@ hash_stats(const char *where, HTAB *hashp)
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fprintf(stderr, "%s: this HTAB -- accesses %ld collisions %ld\n",
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where, hashp->hctl->accesses, hashp->hctl->collisions);
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fprintf(stderr, "hash_stats: entries %ld keysize %ld maxp %d segmentcount %d\n",
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fprintf(stderr, "hash_stats: entries %ld keysize %ld maxp %u segmentcount %ld\n",
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hashp->hctl->nentries, hashp->hctl->keysize,
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hashp->hctl->max_bucket, hashp->hctl->nsegs);
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fprintf(stderr, "%s: total accesses %ld total collisions %ld\n",
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@ -470,7 +469,7 @@ static uint32
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call_hash(HTAB *hashp, void *k)
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||||
{
|
||||
HASHHDR *hctl = hashp->hctl;
|
||||
long hash_val,
|
||||
uint32 hash_val,
|
||||
bucket;
|
||||
|
||||
hash_val = hashp->hash(k, (int) hctl->keysize);
|
||||
@ -479,7 +478,7 @@ call_hash(HTAB *hashp, void *k)
|
||||
if (bucket > hctl->max_bucket)
|
||||
bucket = bucket & hctl->low_mask;
|
||||
|
||||
return (uint32) bucket;
|
||||
return bucket;
|
||||
}
|
||||
|
||||
/*----------
|
||||
@ -647,7 +646,7 @@ hash_search(HTAB *hashp,
|
||||
/* caller is expected to fill the data field on return */
|
||||
|
||||
/* Check if it is time to split the segment */
|
||||
if (++hctl->nentries / (hctl->max_bucket + 1) > hctl->ffactor)
|
||||
if (++hctl->nentries / (long) (hctl->max_bucket + 1) > hctl->ffactor)
|
||||
{
|
||||
/*
|
||||
* NOTE: failure to expand table is not a fatal error, it
|
||||
@ -795,10 +794,10 @@ expand_table(HTAB *hashp)
|
||||
/*
|
||||
* If we crossed a power of 2, readjust masks.
|
||||
*/
|
||||
if (new_bucket > hctl->high_mask)
|
||||
if ((uint32) new_bucket > hctl->high_mask)
|
||||
{
|
||||
hctl->low_mask = hctl->high_mask;
|
||||
hctl->high_mask = new_bucket | hctl->low_mask;
|
||||
hctl->high_mask = (uint32) new_bucket | hctl->low_mask;
|
||||
}
|
||||
|
||||
/*
|
||||
|
||||
@ -9,14 +9,16 @@
|
||||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $Header: /cvsroot/pgsql/src/backend/utils/hash/hashfn.c,v 1.15 2001/10/25 05:49:51 momjian Exp $
|
||||
* $Header: /cvsroot/pgsql/src/backend/utils/hash/hashfn.c,v 1.16 2002/03/09 17:35:36 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
#include "postgres.h"
|
||||
|
||||
#include "access/hash.h"
|
||||
#include "utils/hsearch.h"
|
||||
|
||||
|
||||
/*
|
||||
* string_hash: hash function for keys that are null-terminated strings.
|
||||
*
|
||||
@ -27,91 +29,17 @@
|
||||
*
|
||||
* NOTE: this is the default hash function if none is specified.
|
||||
*/
|
||||
long
|
||||
uint32
|
||||
string_hash(void *key, int keysize)
|
||||
{
|
||||
unsigned char *k = (unsigned char *) key;
|
||||
long h = 0;
|
||||
|
||||
while (*k)
|
||||
h = (h * PRIME1) ^ (*k++);
|
||||
|
||||
h %= PRIME2;
|
||||
|
||||
return h;
|
||||
return DatumGetUInt32(hash_any((unsigned char *) key, strlen((char *) key)));
|
||||
}
|
||||
|
||||
/*
|
||||
* tag_hash: hash function for fixed-size tag values
|
||||
*
|
||||
* NB: we assume that the supplied key is aligned at least on an 'int'
|
||||
* boundary, if its size is >= sizeof(int).
|
||||
*/
|
||||
long
|
||||
uint32
|
||||
tag_hash(void *key, int keysize)
|
||||
{
|
||||
int *k = (int *) key;
|
||||
long h = 0;
|
||||
|
||||
/*
|
||||
* Use four byte chunks in a "jump table" to go a little faster.
|
||||
*
|
||||
* Currently the maximum keysize is 16 (mar 17 1992). I have put in
|
||||
* cases for up to 32. Bigger than this will resort to a for loop
|
||||
* (see the default case).
|
||||
*/
|
||||
switch (keysize)
|
||||
{
|
||||
case 8 * sizeof(int):
|
||||
h = (h * PRIME1) ^(*k++);
|
||||
/* fall through */
|
||||
|
||||
case 7 * sizeof(int):
|
||||
h = (h * PRIME1) ^(*k++);
|
||||
/* fall through */
|
||||
|
||||
case 6 * sizeof(int):
|
||||
h = (h * PRIME1) ^(*k++);
|
||||
/* fall through */
|
||||
|
||||
case 5 * sizeof(int):
|
||||
h = (h * PRIME1) ^(*k++);
|
||||
/* fall through */
|
||||
|
||||
case 4 * sizeof(int):
|
||||
h = (h * PRIME1) ^(*k++);
|
||||
/* fall through */
|
||||
|
||||
case 3 * sizeof(int):
|
||||
h = (h * PRIME1) ^(*k++);
|
||||
/* fall through */
|
||||
|
||||
case 2 * sizeof(int):
|
||||
h = (h * PRIME1) ^(*k++);
|
||||
/* fall through */
|
||||
|
||||
case sizeof(int):
|
||||
h = (h * PRIME1) ^(*k++);
|
||||
break;
|
||||
|
||||
default:
|
||||
/* Do an int at a time */
|
||||
for (; keysize >= (int) sizeof(int); keysize -= sizeof(int))
|
||||
h = (h * PRIME1) ^ (*k++);
|
||||
|
||||
/* Cope with any partial-int leftover bytes */
|
||||
if (keysize > 0)
|
||||
{
|
||||
unsigned char *keybyte = (unsigned char *) k;
|
||||
|
||||
do
|
||||
h = (h * PRIME1) ^ (*keybyte++);
|
||||
while (--keysize > 0);
|
||||
}
|
||||
break;
|
||||
}
|
||||
|
||||
h %= PRIME2;
|
||||
|
||||
return h;
|
||||
return DatumGetUInt32(hash_any((unsigned char *) key, keysize));
|
||||
}
|
||||
|
||||
@ -7,7 +7,7 @@
|
||||
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $Id: hash.h,v 1.44 2002/03/06 20:49:45 momjian Exp $
|
||||
* $Id: hash.h,v 1.45 2002/03/09 17:35:37 tgl Exp $
|
||||
*
|
||||
* NOTES
|
||||
* modeled after Margo Seltzer's hash implementation for unix.
|
||||
@ -252,7 +252,8 @@ extern Datum hashbulkdelete(PG_FUNCTION_ARGS);
|
||||
* Datatype-specific hash functions in hashfunc.c.
|
||||
*
|
||||
* NOTE: some of these are also used by catcache operations, without
|
||||
* any direct connection to hash indexes.
|
||||
* any direct connection to hash indexes. Also, the common hash_any
|
||||
* routine is also used by dynahash tables and hash joins.
|
||||
*/
|
||||
extern Datum hashchar(PG_FUNCTION_ARGS);
|
||||
extern Datum hashint2(PG_FUNCTION_ARGS);
|
||||
@ -265,7 +266,7 @@ extern Datum hashoidvector(PG_FUNCTION_ARGS);
|
||||
extern Datum hashint2vector(PG_FUNCTION_ARGS);
|
||||
extern Datum hashname(PG_FUNCTION_ARGS);
|
||||
extern Datum hashvarlena(PG_FUNCTION_ARGS);
|
||||
extern Datum hash_any(register const char *k, register int keylen);
|
||||
extern Datum hash_any(register const unsigned char *k, register int keylen);
|
||||
|
||||
/* private routines */
|
||||
|
||||
|
||||
@ -7,7 +7,7 @@
|
||||
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $Id: hsearch.h,v 1.25 2001/11/05 17:46:36 momjian Exp $
|
||||
* $Id: hsearch.h,v 1.26 2002/03/09 17:35:37 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -35,9 +35,6 @@
|
||||
#define DEF_DIRSIZE 256
|
||||
#define DEF_FFACTOR 1 /* default fill factor */
|
||||
|
||||
#define PRIME1 37 /* for the hash function */
|
||||
#define PRIME2 1048583
|
||||
|
||||
|
||||
/*
|
||||
* HASHELEMENT is the private part of a hashtable entry. The caller's data
|
||||
@ -60,10 +57,10 @@ typedef struct HASHHDR
|
||||
{
|
||||
long dsize; /* Directory Size */
|
||||
long ssize; /* Segment Size --- must be power of 2 */
|
||||
long sshift; /* Segment shift */
|
||||
long max_bucket; /* ID of Maximum bucket in use */
|
||||
long high_mask; /* Mask to modulo into entire table */
|
||||
long low_mask; /* Mask to modulo into lower half of table */
|
||||
int sshift; /* Segment shift = log2(ssize) */
|
||||
uint32 max_bucket; /* ID of Maximum bucket in use */
|
||||
uint32 high_mask; /* Mask to modulo into entire table */
|
||||
uint32 low_mask; /* Mask to modulo into lower half of table */
|
||||
long ffactor; /* Fill factor */
|
||||
long nentries; /* Number of entries in hash table */
|
||||
long nsegs; /* Number of allocated segments */
|
||||
@ -86,7 +83,7 @@ typedef struct HTAB
|
||||
{
|
||||
HASHHDR *hctl; /* shared control information */
|
||||
HASHSEGMENT *dir; /* directory of segment starts */
|
||||
long (*hash) (void *key, int keysize); /* Hash Function */
|
||||
uint32 (*hash) (void *key, int keysize); /* Hash Function */
|
||||
void *(*alloc) (Size); /* memory allocator */
|
||||
MemoryContext hcxt; /* memory context if default allocator
|
||||
* used */
|
||||
@ -101,7 +98,7 @@ typedef struct HASHCTL
|
||||
long ssize; /* Segment Size */
|
||||
long dsize; /* (initial) Directory Size */
|
||||
long ffactor; /* Fill factor */
|
||||
long (*hash) (void *key, int keysize); /* Hash Function */
|
||||
uint32 (*hash) (void *key, int keysize); /* Hash Function */
|
||||
long keysize; /* hash key length in bytes */
|
||||
long entrysize; /* total user element size in bytes */
|
||||
long max_dsize; /* limit to dsize if directory size is
|
||||
@ -143,7 +140,7 @@ typedef enum
|
||||
typedef struct
|
||||
{
|
||||
HTAB *hashp;
|
||||
long curBucket; /* index of current bucket */
|
||||
uint32 curBucket; /* index of current bucket */
|
||||
HASHELEMENT *curEntry; /* current entry in bucket */
|
||||
} HASH_SEQ_STATUS;
|
||||
|
||||
@ -164,7 +161,7 @@ extern long hash_select_dirsize(long num_entries);
|
||||
/*
|
||||
* prototypes for functions in hashfn.c
|
||||
*/
|
||||
extern long string_hash(void *key, int keysize);
|
||||
extern long tag_hash(void *key, int keysize);
|
||||
extern uint32 string_hash(void *key, int keysize);
|
||||
extern uint32 tag_hash(void *key, int keysize);
|
||||
|
||||
#endif /* HSEARCH_H */
|
||||
|
||||
Loading…
Reference in New Issue
Block a user