gcc/libiberty/sort.c

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/* Sorting algorithms.
2021-01-04 17:26:59 +08:00
Copyright (C) 2000-2021 Free Software Foundation, Inc.
Contributed by Mark Mitchell <mark@codesourcery.com>.
This file is part of GNU CC.
GNU CC is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GNU CC is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with GNU CC; see the file COPYING. If not, write to
the Free Software Foundation, 51 Franklin Street - Fifth Floor,
Boston, MA 02110-1301, USA. */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "libiberty.h"
#include "sort.h"
#ifdef HAVE_LIMITS_H
#include <limits.h>
#endif
#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifndef UCHAR_MAX
#define UCHAR_MAX ((unsigned char)(-1))
#endif
/* POINTERS and WORK are both arrays of N pointers. When this
function returns POINTERS will be sorted in ascending order. */
partition.h: Remove use of PARAMS. include/ 2005-03-27 Gabriel Dos Reis <gdr@integrable-solutions.net> * partition.h: Remove use of PARAMS. * obstack.h: Remove conditional prototypes __STDC__. * objalloc.h: Remove use of PARAMS. * splay-tree.h: Likewise. libiberty/ 2005-03-27 Gabriel Dos Reis <gdr@integrable-solutions.net> Convert libiberty to use ISO C prototype style 5/n. * random.c (srandom, initstate, setstate, random): Use ISO C prototypes. * putenv.c (putenv): Likewise. * physmem.c (physmem_available, physmem_total, main): Likewise. * pex-win32.c (fix_argv, pexecute, pwait): Likewise. * pex-unix.c (pexecute, pwait): Likewise. * pex-msdos.c (pexecute, pwait): Likewise. * pex-djgpp.c (pexecute, pwait): Likewise. * partition.c (partition_new, partition_delete, partition_union) (elem_compare, partition_print): Likewise. * obstack.c (_obstack_begin, _obstack_begin_1, _obstack_newchunk, _obstack_allocated_p, _obstack_free, obstack_free, _obstack_memory_used, print_and_abort, obstack_next_free, obstack_object_size, obstack_base): Likewise. Remove codes predicated on !defined(__STDC__). * objalloc.c (objalloc_create, _objalloc_alloc, objalloc_free, objalloc_free_block): Use ISO C prototypes. * mkstemps.c (mkstemps): Likewise. * memset.c (memset): Likewise. * mempcpy.c (mempcpy): Likewise. * rename.c (rename): Likewise. * rindex.c (rindex): Likewise. * setenv.c (setenv, unsetenv): Likewise. * sigsetmask.c (sigsetmask): Likewise. * snprintf.c (snprintf): Likewise. * sort.c (sort_pointers, xmalloc): Likewise. * spaces.c (spaces): Likewise. * splay-tree.c (splay_tree_delete_helper, splay_tree_splay_helper, splay_tree_splay, splay_tree_foreach_helper, splay_tree_xmalloc_allocate, splay_tree_new, splay_tree_xmalloc_allocate, splay_tree_new_with_allocator, splay_tree_delete, splay_tree_insert, splay_tree_remove, splay_tree_lookup, splay_tree_max, splay_tree_min, splay_tree_predecessor, splay_tree_successor, splay_tree_foreach, splay_tree_compare_ints, splay_tree_compare_pointers): Likewise. * stpcpy.c (stpcpy): Likewise. * stpncpy.c (stpncpy): Likewise. * strcasecmp.c (strcasecmp): Likewise. * strchr.c (strchr): Likewise. * strdup.c (strdup): Likewise. From-SVN: r97125
2005-03-28 12:22:33 +08:00
void sort_pointers (size_t n, void **pointers, void **work)
{
/* The type of a single digit. This can be any unsigned integral
type. When changing this, DIGIT_MAX should be changed as
well. */
typedef unsigned char digit_t;
/* The maximum value a single digit can have. */
#define DIGIT_MAX (UCHAR_MAX + 1)
/* The Ith entry is the number of elements in *POINTERSP that have I
in the digit on which we are currently sorting. */
unsigned int count[DIGIT_MAX];
/* Nonzero if we are running on a big-endian machine. */
int big_endian_p;
size_t i;
size_t j;
/* The algorithm used here is radix sort which takes time linear in
the number of elements in the array. */
/* The algorithm here depends on being able to swap the two arrays
an even number of times. */
if ((sizeof (void *) / sizeof (digit_t)) % 2 != 0)
abort ();
/* Figure out the endianness of the machine. */
for (i = 0, j = 0; i < sizeof (size_t); ++i)
{
j *= (UCHAR_MAX + 1);
j += i;
}
big_endian_p = (((char *)&j)[0] == 0);
/* Move through the pointer values from least significant to most
significant digits. */
for (i = 0; i < sizeof (void *) / sizeof (digit_t); ++i)
{
digit_t *digit;
digit_t *bias;
digit_t *top;
unsigned int *countp;
void **pointerp;
/* The offset from the start of the pointer will depend on the
endianness of the machine. */
if (big_endian_p)
j = sizeof (void *) / sizeof (digit_t) - i;
else
j = i;
/* Now, perform a stable sort on this digit. We use counting
sort. */
memset (count, 0, DIGIT_MAX * sizeof (unsigned int));
/* Compute the address of the appropriate digit in the first and
one-past-the-end elements of the array. On a little-endian
machine, the least-significant digit is closest to the front. */
bias = ((digit_t *) pointers) + j;
top = ((digit_t *) (pointers + n)) + j;
/* Count how many there are of each value. At the end of this
loop, COUNT[K] will contain the number of pointers whose Ith
digit is K. */
for (digit = bias;
digit < top;
digit += sizeof (void *) / sizeof (digit_t))
++count[*digit];
/* Now, make COUNT[K] contain the number of pointers whose Ith
digit is less than or equal to K. */
for (countp = count + 1; countp < count + DIGIT_MAX; ++countp)
*countp += countp[-1];
/* Now, drop the pointers into their correct locations. */
for (pointerp = pointers + n - 1; pointerp >= pointers; --pointerp)
work[--count[((digit_t *) pointerp)[j]]] = *pointerp;
/* Swap WORK and POINTERS so that POINTERS contains the sorted
array. */
pointerp = pointers;
pointers = work;
work = pointerp;
}
}
/* Everything below here is a unit test for the routines in this
file. */
#ifdef UNIT_TEST
#include <stdio.h>
partition.h: Remove use of PARAMS. include/ 2005-03-27 Gabriel Dos Reis <gdr@integrable-solutions.net> * partition.h: Remove use of PARAMS. * obstack.h: Remove conditional prototypes __STDC__. * objalloc.h: Remove use of PARAMS. * splay-tree.h: Likewise. libiberty/ 2005-03-27 Gabriel Dos Reis <gdr@integrable-solutions.net> Convert libiberty to use ISO C prototype style 5/n. * random.c (srandom, initstate, setstate, random): Use ISO C prototypes. * putenv.c (putenv): Likewise. * physmem.c (physmem_available, physmem_total, main): Likewise. * pex-win32.c (fix_argv, pexecute, pwait): Likewise. * pex-unix.c (pexecute, pwait): Likewise. * pex-msdos.c (pexecute, pwait): Likewise. * pex-djgpp.c (pexecute, pwait): Likewise. * partition.c (partition_new, partition_delete, partition_union) (elem_compare, partition_print): Likewise. * obstack.c (_obstack_begin, _obstack_begin_1, _obstack_newchunk, _obstack_allocated_p, _obstack_free, obstack_free, _obstack_memory_used, print_and_abort, obstack_next_free, obstack_object_size, obstack_base): Likewise. Remove codes predicated on !defined(__STDC__). * objalloc.c (objalloc_create, _objalloc_alloc, objalloc_free, objalloc_free_block): Use ISO C prototypes. * mkstemps.c (mkstemps): Likewise. * memset.c (memset): Likewise. * mempcpy.c (mempcpy): Likewise. * rename.c (rename): Likewise. * rindex.c (rindex): Likewise. * setenv.c (setenv, unsetenv): Likewise. * sigsetmask.c (sigsetmask): Likewise. * snprintf.c (snprintf): Likewise. * sort.c (sort_pointers, xmalloc): Likewise. * spaces.c (spaces): Likewise. * splay-tree.c (splay_tree_delete_helper, splay_tree_splay_helper, splay_tree_splay, splay_tree_foreach_helper, splay_tree_xmalloc_allocate, splay_tree_new, splay_tree_xmalloc_allocate, splay_tree_new_with_allocator, splay_tree_delete, splay_tree_insert, splay_tree_remove, splay_tree_lookup, splay_tree_max, splay_tree_min, splay_tree_predecessor, splay_tree_successor, splay_tree_foreach, splay_tree_compare_ints, splay_tree_compare_pointers): Likewise. * stpcpy.c (stpcpy): Likewise. * stpncpy.c (stpncpy): Likewise. * strcasecmp.c (strcasecmp): Likewise. * strchr.c (strchr): Likewise. * strdup.c (strdup): Likewise. From-SVN: r97125
2005-03-28 12:22:33 +08:00
void *xmalloc (size_t n)
{
return malloc (n);
}
int main (int argc, char **argv)
{
int k;
int result;
size_t i;
void **pointers;
void **work;
if (argc > 1)
k = atoi (argv[1]);
else
k = 10;
libiberty.h (ACONCAT): Properly cast value of alloca(). include/ 2005-05-24 Gabriel Dos Reis <gdr@integrable-solutions.net> * libiberty.h (ACONCAT): Properly cast value of alloca(). * ansidecl.h (ATTRIBUTE_UNUSED_LABEL): Don't define if __cplusplus. libiberty/ 2005-05-24 Gabriel Dos Reis <gdr@integrable-solutions.net> * configure.ac: Check declarations for calloc(), getenv(), malloc(), realloc() and sbrk(). * config.in: Regenerate. * configure: Likewise. * alloca.c (C_alloca): Change "new" to "new_storage". Use XNEWVEC instead of xmalloc. * choose-temp.c (choose_temp_base): Use XNEWVEC instea od xmalloc. * concat.c (liiberty_concat_ptr): Surround definition with an extern "C" block, if __cplusplus. (concat): Use XNEWVEC instead of xmalloc. (reconcat): Likewise. * cp-demangle.c (struct d_print_template): Rename member "template" to "template_decl". Adjust use throughout the file. (d_print_resize): Properly cast return value of realloc(). (cplus_demangle_print): Same for malloc(). (d_demangle): Likewise. * cp-demint.c (cplus_demangle_fill_builtin_type): Rename parameter "typename" to "type_name". * cplus-dem.c (grow_vect): Use XRESIZEVEC instead of xrealloc(). (work_stuff_copy_to_from): Use XNEWVEC insteand of xmalloc(). (demangle_template_value_parm): Likewise. (demangle_template): Likewise. (recursively_demangle): Likewise. (do_hpacc_template_literal): Likewise. (do_arg): Likewise. (remember_type): Likewise. (remember_Ktype): Likewise. (register_Btype): Likewise. (string_need): Use XRESIZEVEC instead of xrealloc(). * dyn-string.c (dyn_string_init): Use XNEWVEC. (dyn_string_new): Use XNEW. (dyn_string_resize): Use XRESIZEVEC. * fnmatch.c (fnmatch): Rename local variable "not" to "negate". * getopt.c (getenv): Declare only if !__cplusplus and !getenv. Otherwise include <stdlib.h>. (exchange): Cast return value of malloc(). * hashtab.c (htab_size): Define as both macro and non-inline function. (htab_elements): Likewise. * getpwd.c (getpwd): Use XNEWVEC. (htab_create_alloc_ex): Use C90 prototype-style. * lrealpath.c (lrealpath): Appropriately cast return value of malloc(). * make-relative-prefix.c (save_string): Likewise. * make-temp-file.c (try_dir): Rename from "try". Adjust use in the file. (choose_tmpdir): Use XNEWVEC. * mkstemps.c (mkstemps): Rename parameter "template" to "pattern". * pex-common.c (pex_init_common): Use XNEW. (pex_add_remove): Use XRESIZEVEC. (pex_run): Likewise. (pex_get_status_and_time): Likewise. * pex-djgpp.c (pex_djgpp_exec_child): Likewise. * pex-msdos.c (pex_init): Use XNEW. (pex_msdos_exec_child): Likewise. (pex_msdos_exec_child): Use XRESIZEVEC. * pex-unix.c (pex_wait): Use XNEW. * pex-win32.c (fix_argv): Use XNEWVEC. * pexecute.c (pwait): Likewise. * setenv.c (setenv): Properly cast return value of malloc(). * sigsetmask.c (sigsetmask): Rename local variables "old" and "new" to "old_sig" and "new_sig". * sort.c (main): Use XNEWVEC. * spaces.c (spaces): Cast return value of malloc(). * strndup.c (strndup): Likewise. * ternary.c (ternary_insert): Use XNEW. * xmalloc.c (malloc, realloc, calloc, sbrk): Surround declaration with an extern "C" block if __cplusplus. * xstrdup.c (xstrdup): Cast return value of memcpy(). * xstrerror.c (strerror): Enclose declaration in an extern "C" block if __cplusplus. * xstrndup.c (xstrndup): Use XNEW. Cast return value of memcpy(). From-SVN: r100115
2005-05-25 04:48:25 +08:00
pointers = XNEWVEC (void*, k);
work = XNEWVEC (void*, k);
for (i = 0; i < k; ++i)
{
pointers[i] = (void *) random ();
printf ("%x\n", pointers[i]);
}
sort_pointers (k, pointers, work);
printf ("\nSorted\n\n");
result = 0;
for (i = 0; i < k; ++i)
{
printf ("%x\n", pointers[i]);
if (i > 0 && (char*) pointers[i] < (char*) pointers[i - 1])
result = 1;
}
free (pointers);
free (work);
return result;
}
#endif