+++ /dev/null
-#!/usr/bin/perl
-
-#
-# gen_qsort_tuple.pl
-#
-# This script generates specialized versions of the quicksort algorithm for
-# tuple sorting. The quicksort code is derived from the NetBSD code. The
-# code generated by this script runs significantly faster than vanilla qsort
-# when used to sort tuples. This speedup comes from a number of places.
-# The major effects are (1) inlining simple tuple comparators is much faster
-# than jumping through a function pointer and (2) swap and vecswap operations
-# specialized to the particular data type of interest (in this case, SortTuple)
-# are faster than the generic routines.
-#
-# Modifications from vanilla NetBSD source:
-# Add do ... while() macro fix
-# Remove __inline, _DIAGASSERTs, __P
-# Remove ill-considered "swap_cnt" switch to insertion sort,
-# in favor of a simple check for presorted input.
-# Take care to recurse on the smaller partition, to bound stack usage.
-#
-# Instead of sorting arbitrary objects, we're always sorting SortTuples.
-# Add CHECK_FOR_INTERRUPTS().
-#
-# CAUTION: if you change this file, see also qsort.c and qsort_arg.c
-#
-
-use strict;
-use warnings;
-
-my $SUFFIX;
-my $EXTRAARGS;
-my $EXTRAPARAMS;
-my $CMPPARAMS;
-
-emit_qsort_boilerplate();
-
-$SUFFIX = 'tuple';
-$EXTRAARGS = ', SortTupleComparator cmp_tuple, Tuplesortstate *state';
-$EXTRAPARAMS = ', cmp_tuple, state';
-$CMPPARAMS = ', state';
-emit_qsort_implementation();
-
-$SUFFIX = 'ssup';
-$EXTRAARGS = ', SortSupport ssup';
-$EXTRAPARAMS = ', ssup';
-$CMPPARAMS = ', ssup';
-print <<'EOM';
-
-#define cmp_ssup(a, b, ssup) \
- ApplySortComparator((a)->datum1, (a)->isnull1, \
- (b)->datum1, (b)->isnull1, ssup)
-
-EOM
-emit_qsort_implementation();
-
-sub emit_qsort_boilerplate
-{
- print <<'EOM';
-/*
- * autogenerated by src/backend/utils/sort/gen_qsort_tuple.pl, do not edit!
- *
- * This file is included by tuplesort.c, rather than compiled separately.
- */
-
-/* $NetBSD: qsort.c,v 1.13 2003/08/07 16:43:42 agc Exp $ */
-
-/*-
- * Copyright (c) 1992, 1993
- * The Regents of the University of California. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the University nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-/*
- * Qsort routine based on J. L. Bentley and M. D. McIlroy,
- * "Engineering a sort function",
- * Software--Practice and Experience 23 (1993) 1249-1265.
- *
- * We have modified their original by adding a check for already-sorted input,
- * which seems to be a win per discussions on pgsql-hackers around 2006-03-21.
- *
- * Also, we recurse on the smaller partition and iterate on the larger one,
- * which ensures we cannot recurse more than log(N) levels (since the
- * partition recursed to is surely no more than half of the input). Bentley
- * and McIlroy explicitly rejected doing this on the grounds that it's "not
- * worth the effort", but we have seen crashes in the field due to stack
- * overrun, so that judgment seems wrong.
- */
-
-static void
-swapfunc(SortTuple *a, SortTuple *b, size_t n)
-{
- do
- {
- SortTuple t = *a;
-
- *a++ = *b;
- *b++ = t;
- } while (--n > 0);
-}
-
-#define swap(a, b) \
- do { \
- SortTuple t = *(a); \
- *(a) = *(b); \
- *(b) = t; \
- } while (0)
-
-#define vecswap(a, b, n) if ((n) > 0) swapfunc(a, b, n)
-
-EOM
-
- return;
-}
-
-sub emit_qsort_implementation
-{
- print <<EOM;
-static SortTuple *
-med3_$SUFFIX(SortTuple *a, SortTuple *b, SortTuple *c$EXTRAARGS)
-{
- return cmp_$SUFFIX(a, b$CMPPARAMS) < 0 ?
- (cmp_$SUFFIX(b, c$CMPPARAMS) < 0 ? b :
- (cmp_$SUFFIX(a, c$CMPPARAMS) < 0 ? c : a))
- : (cmp_$SUFFIX(b, c$CMPPARAMS) > 0 ? b :
- (cmp_$SUFFIX(a, c$CMPPARAMS) < 0 ? a : c));
-}
-
-static void
-qsort_$SUFFIX(SortTuple *a, size_t n$EXTRAARGS)
-{
- SortTuple *pa,
- *pb,
- *pc,
- *pd,
- *pl,
- *pm,
- *pn;
- size_t d1,
- d2;
- int r,
- presorted;
-
-loop:
- CHECK_FOR_INTERRUPTS();
- if (n < 7)
- {
- for (pm = a + 1; pm < a + n; pm++)
- for (pl = pm; pl > a && cmp_$SUFFIX(pl - 1, pl$CMPPARAMS) > 0; pl--)
- swap(pl, pl - 1);
- return;
- }
- presorted = 1;
- for (pm = a + 1; pm < a + n; pm++)
- {
- CHECK_FOR_INTERRUPTS();
- if (cmp_$SUFFIX(pm - 1, pm$CMPPARAMS) > 0)
- {
- presorted = 0;
- break;
- }
- }
- if (presorted)
- return;
- pm = a + (n / 2);
- if (n > 7)
- {
- pl = a;
- pn = a + (n - 1);
- if (n > 40)
- {
- size_t d = (n / 8);
-
- pl = med3_$SUFFIX(pl, pl + d, pl + 2 * d$EXTRAPARAMS);
- pm = med3_$SUFFIX(pm - d, pm, pm + d$EXTRAPARAMS);
- pn = med3_$SUFFIX(pn - 2 * d, pn - d, pn$EXTRAPARAMS);
- }
- pm = med3_$SUFFIX(pl, pm, pn$EXTRAPARAMS);
- }
- swap(a, pm);
- pa = pb = a + 1;
- pc = pd = a + (n - 1);
- for (;;)
- {
- while (pb <= pc && (r = cmp_$SUFFIX(pb, a$CMPPARAMS)) <= 0)
- {
- if (r == 0)
- {
- swap(pa, pb);
- pa++;
- }
- pb++;
- CHECK_FOR_INTERRUPTS();
- }
- while (pb <= pc && (r = cmp_$SUFFIX(pc, a$CMPPARAMS)) >= 0)
- {
- if (r == 0)
- {
- swap(pc, pd);
- pd--;
- }
- pc--;
- CHECK_FOR_INTERRUPTS();
- }
- if (pb > pc)
- break;
- swap(pb, pc);
- pb++;
- pc--;
- }
- pn = a + n;
- d1 = Min(pa - a, pb - pa);
- vecswap(a, pb - d1, d1);
- d1 = Min(pd - pc, pn - pd - 1);
- vecswap(pb, pn - d1, d1);
- d1 = pb - pa;
- d2 = pd - pc;
- if (d1 <= d2)
- {
- /* Recurse on left partition, then iterate on right partition */
- if (d1 > 1)
- qsort_$SUFFIX(a, d1$EXTRAPARAMS);
- if (d2 > 1)
- {
- /* Iterate rather than recurse to save stack space */
- /* qsort_$SUFFIX(pn - d2, d2$EXTRAPARAMS); */
- a = pn - d2;
- n = d2;
- goto loop;
- }
- }
- else
- {
- /* Recurse on right partition, then iterate on left partition */
- if (d2 > 1)
- qsort_$SUFFIX(pn - d2, d2$EXTRAPARAMS);
- if (d1 > 1)
- {
- /* Iterate rather than recurse to save stack space */
- /* qsort_$SUFFIX(a, d1$EXTRAPARAMS); */
- n = d1;
- goto loop;
- }
- }
-}
-EOM
-
- return;
-}
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