From c73967d0ca14e06432949c96e047297c9e9f37c9 Mon Sep 17 00:00:00 2001 From: Thomas Munro Date: Wed, 19 Aug 2020 19:34:45 +1200 Subject: [PATCH 2/3] Use sort_template.h for qsort() and qsort_arg(). Reduce duplication by using the new template. --- src/port/qsort.c | 227 ++---------------------------------------- src/port/qsort_arg.c | 228 ++----------------------------------------- 2 files changed, 15 insertions(+), 440 deletions(-) diff --git a/src/port/qsort.c b/src/port/qsort.c index fa992e2081..7879e6cd56 100644 --- a/src/port/qsort.c +++ b/src/port/qsort.c @@ -1,229 +1,16 @@ /* * qsort.c: standard quicksort algorithm - * - * 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. - * - * CAUTION: if you change this file, see also qsort_arg.c, gen_qsort_tuple.pl - * - * src/port/qsort.c - */ - -/* $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. */ #include "c.h" - -static char *med3(char *a, char *b, char *c, - int (*cmp) (const void *, const void *)); -static void swapfunc(char *, char *, size_t, int); - -/* - * 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. - */ - -#define swapcode(TYPE, parmi, parmj, n) \ -do { \ - size_t i = (n) / sizeof (TYPE); \ - TYPE *pi = (TYPE *)(void *)(parmi); \ - TYPE *pj = (TYPE *)(void *)(parmj); \ - do { \ - TYPE t = *pi; \ - *pi++ = *pj; \ - *pj++ = t; \ - } while (--i > 0); \ -} while (0) - -#define SWAPINIT(a, es) swaptype = ((char *)(a) - (char *)0) % sizeof(long) || \ - (es) % sizeof(long) ? 2 : (es) == sizeof(long)? 0 : 1 - -static void -swapfunc(char *a, char *b, size_t n, int swaptype) -{ - if (swaptype <= 1) - swapcode(long, a, b, n); - else - swapcode(char, a, b, n); -} - -#define swap(a, b) \ - if (swaptype == 0) { \ - long t = *(long *)(void *)(a); \ - *(long *)(void *)(a) = *(long *)(void *)(b); \ - *(long *)(void *)(b) = t; \ - } else \ - swapfunc(a, b, es, swaptype) - -#define vecswap(a, b, n) if ((n) > 0) swapfunc(a, b, n, swaptype) - -static char * -med3(char *a, char *b, char *c, int (*cmp) (const void *, const void *)) -{ - return cmp(a, b) < 0 ? - (cmp(b, c) < 0 ? b : (cmp(a, c) < 0 ? c : a)) - : (cmp(b, c) > 0 ? b : (cmp(a, c) < 0 ? a : c)); -} - -void -pg_qsort(void *a, size_t n, size_t es, int (*cmp) (const void *, const void *)) -{ - char *pa, - *pb, - *pc, - *pd, - *pl, - *pm, - *pn; - size_t d1, - d2; - int r, - swaptype, - presorted; - -loop:SWAPINIT(a, es); - if (n < 7) - { - for (pm = (char *) a + es; pm < (char *) a + n * es; pm += es) - for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0; - pl -= es) - swap(pl, pl - es); - return; - } - presorted = 1; - for (pm = (char *) a + es; pm < (char *) a + n * es; pm += es) - { - if (cmp(pm - es, pm) > 0) - { - presorted = 0; - break; - } - } - if (presorted) - return; - pm = (char *) a + (n / 2) * es; - if (n > 7) - { - pl = (char *) a; - pn = (char *) a + (n - 1) * es; - if (n > 40) - { - size_t d = (n / 8) * es; - - pl = med3(pl, pl + d, pl + 2 * d, cmp); - pm = med3(pm - d, pm, pm + d, cmp); - pn = med3(pn - 2 * d, pn - d, pn, cmp); - } - pm = med3(pl, pm, pn, cmp); - } - swap(a, pm); - pa = pb = (char *) a + es; - pc = pd = (char *) a + (n - 1) * es; - for (;;) - { - while (pb <= pc && (r = cmp(pb, a)) <= 0) - { - if (r == 0) - { - swap(pa, pb); - pa += es; - } - pb += es; - } - while (pb <= pc && (r = cmp(pc, a)) >= 0) - { - if (r == 0) - { - swap(pc, pd); - pd -= es; - } - pc -= es; - } - if (pb > pc) - break; - swap(pb, pc); - pb += es; - pc -= es; - } - pn = (char *) a + n * es; - d1 = Min(pa - (char *) a, pb - pa); - vecswap(a, pb - d1, d1); - d1 = Min(pd - pc, pn - pd - es); - 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 > es) - pg_qsort(a, d1 / es, es, cmp); - if (d2 > es) - { - /* Iterate rather than recurse to save stack space */ - /* pg_qsort(pn - d2, d2 / es, es, cmp); */ - a = pn - d2; - n = d2 / es; - goto loop; - } - } - else - { - /* Recurse on right partition, then iterate on left partition */ - if (d2 > es) - pg_qsort(pn - d2, d2 / es, es, cmp); - if (d1 > es) - { - /* Iterate rather than recurse to save stack space */ - /* pg_qsort(a, d1 / es, es, cmp); */ - n = d1 / es; - goto loop; - } - } -} +#define ST_SORT pg_qsort +#define ST_ELEMENT_TYPE_VOID +#define ST_COMPARE_RUNTIME_POINTER +#define ST_SCOPE +#define ST_DECLARE +#define ST_DEFINE +#include "lib/sort_template.h" /* * qsort comparator wrapper for strcmp. diff --git a/src/port/qsort_arg.c b/src/port/qsort_arg.c index 6d54fbc2b4..fa7e11a3b8 100644 --- a/src/port/qsort_arg.c +++ b/src/port/qsort_arg.c @@ -1,226 +1,14 @@ /* * qsort_arg.c: qsort with a passthrough "void *" argument - * - * 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. - * - * CAUTION: if you change this file, see also qsort.c, gen_qsort_tuple.pl - * - * src/port/qsort_arg.c - */ - -/* $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. */ #include "c.h" - -static char *med3(char *a, char *b, char *c, - qsort_arg_comparator cmp, void *arg); -static void swapfunc(char *, char *, size_t, int); - -/* - * 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. - */ - -#define swapcode(TYPE, parmi, parmj, n) \ -do { \ - size_t i = (n) / sizeof (TYPE); \ - TYPE *pi = (TYPE *)(void *)(parmi); \ - TYPE *pj = (TYPE *)(void *)(parmj); \ - do { \ - TYPE t = *pi; \ - *pi++ = *pj; \ - *pj++ = t; \ - } while (--i > 0); \ -} while (0) - -#define SWAPINIT(a, es) swaptype = ((char *)(a) - (char *)0) % sizeof(long) || \ - (es) % sizeof(long) ? 2 : (es) == sizeof(long)? 0 : 1 - -static void -swapfunc(char *a, char *b, size_t n, int swaptype) -{ - if (swaptype <= 1) - swapcode(long, a, b, n); - else - swapcode(char, a, b, n); -} - -#define swap(a, b) \ - if (swaptype == 0) { \ - long t = *(long *)(void *)(a); \ - *(long *)(void *)(a) = *(long *)(void *)(b); \ - *(long *)(void *)(b) = t; \ - } else \ - swapfunc(a, b, es, swaptype) - -#define vecswap(a, b, n) if ((n) > 0) swapfunc(a, b, n, swaptype) - -static char * -med3(char *a, char *b, char *c, qsort_arg_comparator cmp, void *arg) -{ - return cmp(a, b, arg) < 0 ? - (cmp(b, c, arg) < 0 ? b : (cmp(a, c, arg) < 0 ? c : a)) - : (cmp(b, c, arg) > 0 ? b : (cmp(a, c, arg) < 0 ? a : c)); -} - -void -qsort_arg(void *a, size_t n, size_t es, qsort_arg_comparator cmp, void *arg) -{ - char *pa, - *pb, - *pc, - *pd, - *pl, - *pm, - *pn; - size_t d1, - d2; - int r, - swaptype, - presorted; - -loop:SWAPINIT(a, es); - if (n < 7) - { - for (pm = (char *) a + es; pm < (char *) a + n * es; pm += es) - for (pl = pm; pl > (char *) a && cmp(pl - es, pl, arg) > 0; - pl -= es) - swap(pl, pl - es); - return; - } - presorted = 1; - for (pm = (char *) a + es; pm < (char *) a + n * es; pm += es) - { - if (cmp(pm - es, pm, arg) > 0) - { - presorted = 0; - break; - } - } - if (presorted) - return; - pm = (char *) a + (n / 2) * es; - if (n > 7) - { - pl = (char *) a; - pn = (char *) a + (n - 1) * es; - if (n > 40) - { - size_t d = (n / 8) * es; - - pl = med3(pl, pl + d, pl + 2 * d, cmp, arg); - pm = med3(pm - d, pm, pm + d, cmp, arg); - pn = med3(pn - 2 * d, pn - d, pn, cmp, arg); - } - pm = med3(pl, pm, pn, cmp, arg); - } - swap(a, pm); - pa = pb = (char *) a + es; - pc = pd = (char *) a + (n - 1) * es; - for (;;) - { - while (pb <= pc && (r = cmp(pb, a, arg)) <= 0) - { - if (r == 0) - { - swap(pa, pb); - pa += es; - } - pb += es; - } - while (pb <= pc && (r = cmp(pc, a, arg)) >= 0) - { - if (r == 0) - { - swap(pc, pd); - pd -= es; - } - pc -= es; - } - if (pb > pc) - break; - swap(pb, pc); - pb += es; - pc -= es; - } - pn = (char *) a + n * es; - d1 = Min(pa - (char *) a, pb - pa); - vecswap(a, pb - d1, d1); - d1 = Min(pd - pc, pn - pd - es); - 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 > es) - qsort_arg(a, d1 / es, es, cmp, arg); - if (d2 > es) - { - /* Iterate rather than recurse to save stack space */ - /* qsort_arg(pn - d2, d2 / es, es, cmp, arg); */ - a = pn - d2; - n = d2 / es; - goto loop; - } - } - else - { - /* Recurse on right partition, then iterate on left partition */ - if (d2 > es) - qsort_arg(pn - d2, d2 / es, es, cmp, arg); - if (d1 > es) - { - /* Iterate rather than recurse to save stack space */ - /* qsort_arg(a, d1 / es, es, cmp, arg); */ - n = d1 / es; - goto loop; - } - } -} +#define ST_SORT qsort_arg +#define ST_ELEMENT_TYPE_VOID +#define ST_COMPARATOR_TYPE_NAME qsort_arg_comparator +#define ST_COMPARE_RUNTIME_POINTER +#define ST_COMPARE_ARG_TYPE void +#define ST_SCOPE +#define ST_DEFINE +#include "lib/sort_template.h" -- 2.30.0