From eeb0656f22538a0a3ca30b0761dc54ccda3837f5 Mon Sep 17 00:00:00 2001 From: Mark Mitchell Date: Mon, 24 Apr 2000 00:51:08 +0000 Subject: [PATCH] sort.c: New file. * sort.c: New file. * Makefile.in (CFILES): Add sort.c (REQUIRED_OFILES): Add sort.o. (sort.o): New target. From-SVN: r33364 --- libiberty/ChangeLog | 7 ++ libiberty/Makefile.in | 9 ++- libiberty/sort.c | 176 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 188 insertions(+), 4 deletions(-) create mode 100644 libiberty/sort.c diff --git a/libiberty/ChangeLog b/libiberty/ChangeLog index c8bd757aaa8f..eb8ddfcce9e8 100644 --- a/libiberty/ChangeLog +++ b/libiberty/ChangeLog @@ -1,3 +1,10 @@ +2000-04-23 Mark Mitchell + + * sort.c: New file. + * Makefile.in (CFILES): Add sort.c + (REQUIRED_OFILES): Add sort.o. + (sort.o): New target. + 2000-04-21 Michael Sokolov * Makefile.in (*-subdir): Revamp slightly to avoid losing on diff --git a/libiberty/Makefile.in b/libiberty/Makefile.in index 054454e60968..acb601193355 100644 --- a/libiberty/Makefile.in +++ b/libiberty/Makefile.in @@ -1,6 +1,6 @@ # # Makefile -# Copyright (C) 1990, 91 - 99, 2000 +# Copyright (C) 1990, 91, 91 - 99, 2000 # Free Software Foundation # # This file is part of the libiberty library. @@ -129,7 +129,7 @@ CFILES = asprintf.c alloca.c argv.c atexit.c basename.c bcmp.c bcopy.c \ getruntime.c floatformat.c hashtab.c hex.c index.c insque.c memchr.c \ memcmp.c memcpy.c memmove.c memset.c mkstemps.c objalloc.c obstack.c \ partition.c pexecute.c putenv.c random.c rename.c rindex.c \ - setenv.c sigsetmask.c spaces.c splay-tree.c strcasecmp.c \ + setenv.c sigsetmask.c sort.c spaces.c splay-tree.c strcasecmp.c \ strncasecmp.c strchr.c strdup.c strerror.c strrchr.c \ strsignal.c strstr.c strtod.c strtol.c strtoul.c tmpnam.c \ vasprintf.c vfork.c vfprintf.c vprintf.c vsprintf.c waitpid.c \ @@ -138,8 +138,8 @@ CFILES = asprintf.c alloca.c argv.c atexit.c basename.c bcmp.c bcopy.c \ # These are always included in the library. REQUIRED_OFILES = argv.o choose-temp.o concat.o cplus-dem.o \ fdmatch.o fnmatch.o getopt.o getopt1.o getpwd.o getruntime.o hashtab.o \ - hex.o floatformat.o objalloc.o obstack.o partition.o pexecute.o spaces.o \ - splay-tree.o strerror.o strsignal.o xatexit.o xexit.o xmalloc.o \ + hex.o floatformat.o objalloc.o obstack.o partition.o pexecute.o sort.o \ + spaces.o splay-tree.o strerror.o strsignal.o xatexit.o xexit.o xmalloc.o \ xmemdup.o xstrdup.o xstrerror.o $(TARGETLIB): $(REQUIRED_OFILES) $(EXTRA_OFILES) $(LIBOBJS) $(ALLOCA) @@ -276,6 +276,7 @@ obstack.o: config.h $(INCDIR)/obstack.h partition.o: config.h $(INCDIR)/partition.h pexecute.o: config.h $(INCDIR)/libiberty.h setenv.o: config.h +sort.o: config.h $(INCDIR)/sort.h $(INCDIR)/ansidecl.h spaces.o: $(INCDIR)/libiberty.h splay-tree.o: config.h $(INCDIR)/libiberty.h $(INCDIR)/splay-tree.h $(INCDIR)/ansidecl.h strerror.o: config.h $(INCDIR)/libiberty.h diff --git a/libiberty/sort.c b/libiberty/sort.c new file mode 100644 index 000000000000..6dca09a9242e --- /dev/null +++ b/libiberty/sort.c @@ -0,0 +1,176 @@ +/* Sorting algorithms. + Copyright (C) 2000 Free Software Foundation, Inc. + Contributed by Mark Mitchell . + +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, 59 Temple Place - Suite 330, +Boston, MA 02111-1307, USA. */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif +#include "libiberty.h" +#include "sort.h" +#include +#ifdef HAVE_STDLIB_H +#include +#endif + +/* POINTERSP and WORKP both point to arrays of N pointers. When + this function returns POINTERSP will point to a sorted version of + the original array pointed to by POINTERSP. */ + +void sort_pointers (n, pointers, work) + 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; i < sizeof (size_t); ++i) + ((char *)&j)[i] = 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) + i; + top = ((digit_t *) (pointers + n)) + i; + + /* 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)[i]]] = *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 + +void *xmalloc (n) + 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; + + pointers = xmalloc (k * sizeof (void *)); + work = xmalloc (k * sizeof (void *)); + + 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 -- 2.43.5