2000-03-25 03:14:57 +01:00
|
|
|
/* List implentation of a partition of consecutive integers.
|
|
|
|
Copyright (C) 2000 Free Software Foundation, Inc.
|
|
|
|
Contributed by CodeSourcery, LLC.
|
|
|
|
|
|
|
|
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
|
|
|
|
|
|
|
|
#ifdef HAVE_STDLIB_H
|
|
|
|
#include <stdlib.h>
|
|
|
|
#endif
|
|
|
|
|
2000-05-29 22:45:32 +02:00
|
|
|
#ifdef HAVE_STRING_H
|
|
|
|
#include <string.h>
|
|
|
|
#endif
|
|
|
|
|
2000-03-25 03:14:57 +01:00
|
|
|
#include "libiberty.h"
|
|
|
|
#include "partition.h"
|
|
|
|
|
|
|
|
/* Creates a partition of NUM_ELEMENTS elements. Initially each
|
|
|
|
element is in a class by itself. */
|
|
|
|
|
|
|
|
partition
|
|
|
|
partition_new (num_elements)
|
|
|
|
int num_elements;
|
|
|
|
{
|
|
|
|
int e;
|
|
|
|
|
|
|
|
partition part = (partition)
|
|
|
|
xmalloc (sizeof (struct partition_def) +
|
|
|
|
(num_elements - 1) * sizeof (struct partition_elem));
|
|
|
|
part->num_elements = num_elements;
|
|
|
|
for (e = 0; e < num_elements; ++e)
|
|
|
|
{
|
|
|
|
part->elements[e].class_element = e;
|
|
|
|
part->elements[e].next = &(part->elements[e]);
|
|
|
|
part->elements[e].class_count = 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
return part;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Freeds a partition. */
|
|
|
|
|
|
|
|
void
|
|
|
|
partition_delete (part)
|
|
|
|
partition part;
|
|
|
|
{
|
|
|
|
free (part);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Unites the classes containing ELEM1 and ELEM2 into a single class
|
|
|
|
of partition PART. If ELEM1 and ELEM2 are already in the same
|
|
|
|
class, does nothing. Returns the canonical element of the
|
|
|
|
resulting union class. */
|
|
|
|
|
|
|
|
int
|
|
|
|
partition_union (part, elem1, elem2)
|
|
|
|
partition part;
|
|
|
|
int elem1;
|
|
|
|
int elem2;
|
|
|
|
{
|
|
|
|
struct partition_elem *elements = part->elements;
|
|
|
|
struct partition_elem *e1;
|
|
|
|
struct partition_elem *e2;
|
|
|
|
struct partition_elem *p;
|
|
|
|
struct partition_elem *old_next;
|
|
|
|
/* The canonical element of the resulting union class. */
|
|
|
|
int class_element = elements[elem1].class_element;
|
|
|
|
|
|
|
|
/* If they're already in the same class, do nothing. */
|
|
|
|
if (class_element == elements[elem2].class_element)
|
|
|
|
return class_element;
|
|
|
|
|
|
|
|
/* Make sure ELEM1 is in the larger class of the two. If not, swap
|
|
|
|
them. This way we always scan the shorter list. */
|
|
|
|
if (elements[elem1].class_count < elements[elem2].class_count)
|
|
|
|
{
|
|
|
|
int temp = elem1;
|
|
|
|
elem1 = elem2;
|
|
|
|
elem2 = temp;
|
|
|
|
class_element = elements[elem1].class_element;
|
|
|
|
}
|
|
|
|
|
|
|
|
e1 = &(elements[elem1]);
|
|
|
|
e2 = &(elements[elem2]);
|
|
|
|
|
|
|
|
/* Keep a count of the number of elements in the list. */
|
|
|
|
elements[class_element].class_count
|
|
|
|
+= elements[e2->class_element].class_count;
|
|
|
|
|
|
|
|
/* Update the class fields in elem2's class list. */
|
|
|
|
e2->class_element = class_element;
|
|
|
|
for (p = e2->next; p != e2; p = p->next)
|
|
|
|
p->class_element = class_element;
|
|
|
|
|
|
|
|
/* Splice ELEM2's class list into ELEM1's. These are circular
|
|
|
|
lists. */
|
|
|
|
old_next = e1->next;
|
|
|
|
e1->next = e2->next;
|
|
|
|
e2->next = old_next;
|
|
|
|
|
|
|
|
return class_element;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Compare elements ELEM1 and ELEM2 from array of integers, given a
|
|
|
|
pointer to each. Used to qsort such an array. */
|
|
|
|
|
|
|
|
static int
|
|
|
|
elem_compare (elem1, elem2)
|
|
|
|
const void *elem1;
|
|
|
|
const void *elem2;
|
|
|
|
{
|
|
|
|
int e1 = * (int *) elem1;
|
|
|
|
int e2 = * (int *) elem2;
|
|
|
|
if (e1 < e2)
|
|
|
|
return -1;
|
|
|
|
else if (e1 > e2)
|
|
|
|
return 1;
|
|
|
|
else
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Prints PART to the file pointer FP. The elements of each
|
|
|
|
class are sorted. */
|
|
|
|
|
|
|
|
void
|
|
|
|
partition_print (part, fp)
|
|
|
|
partition part;
|
|
|
|
FILE *fp;
|
|
|
|
{
|
|
|
|
char *done;
|
|
|
|
int num_elements = part->num_elements;
|
|
|
|
struct partition_elem *elements = part->elements;
|
|
|
|
int *class_elements;
|
|
|
|
int e;
|
|
|
|
|
|
|
|
/* Flag the elements we've already printed. */
|
|
|
|
done = (char *) xmalloc (num_elements);
|
|
|
|
memset (done, 0, num_elements);
|
|
|
|
|
|
|
|
/* A buffer used to sort elements in a class. */
|
|
|
|
class_elements = (int *) xmalloc (num_elements * sizeof (int));
|
|
|
|
|
|
|
|
fputc ('[', fp);
|
|
|
|
for (e = 0; e < num_elements; ++e)
|
|
|
|
/* If we haven't printed this element, print its entire class. */
|
|
|
|
if (! done[e])
|
|
|
|
{
|
|
|
|
int c = e;
|
|
|
|
int count = elements[elements[e].class_element].class_count;
|
|
|
|
int i;
|
|
|
|
|
|
|
|
/* Collect the elements in this class. */
|
|
|
|
for (i = 0; i < count; ++i) {
|
|
|
|
class_elements[i] = c;
|
|
|
|
done[c] = 1;
|
|
|
|
c = elements[c].next - elements;
|
|
|
|
}
|
|
|
|
/* Sort them. */
|
|
|
|
qsort ((void *) class_elements, count, sizeof (int), &elem_compare);
|
|
|
|
/* Print them. */
|
|
|
|
fputc ('(', fp);
|
|
|
|
for (i = 0; i < count; ++i)
|
|
|
|
fprintf (fp, i == 0 ? "%d" : " %d", class_elements[i]);
|
|
|
|
fputc (')', fp);
|
|
|
|
}
|
|
|
|
fputc (']', fp);
|
|
|
|
|
|
|
|
free (done);
|
|
|
|
}
|
|
|
|
|