Initial revision

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@14420 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 583 insertions, 0 deletions

diff --git a/gcc/bitmap.c b/gcc/bitmap.c
new file mode 100644
index 00000000000..70845c06d10
--- /dev/null
+++ b/gcc/bitmap.c
@@ -0,0 +1,583 @@
+/* Functions to support general ended bitmaps.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+
+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.  */
+
+#include <stdio.h>
+#include "config.h"
+#include "rtl.h"
+#include "flags.h"
+#include "obstack.h"
+#include "regs.h"
+#include "basic-block.h"
+
+/* The contents of the current function definition are allocated
+   in this obstack, and all are freed at the end of the function.
+   For top-level functions, this is temporary_obstack.
+   Separate obstacks are made for nested functions.  */
+
+extern struct obstack *function_obstack;
+
+
+#ifndef INLINE
+#ifndef __GNUC__
+#define INLINE
+#else
+#define INLINE __inline__
+#endif
+#endif
+
+/* Global data */
+bitmap_element bitmap_zero;		/* An element of all zero bits. */
+bitmap_element *bitmap_free;		/* Freelist of bitmap elements. */
+
+static void bitmap_element_free		PROTO((bitmap, bitmap_element *));
+static bitmap_element *bitmap_element_allocate PROTO((bitmap));
+static int bitmap_element_zerop		PROTO((bitmap_element *));
+static void bitmap_element_link		PROTO((bitmap, bitmap_element *));
+static bitmap_element *bitmap_find_bit	PROTO((bitmap, unsigned int));
+
+/* Free a bitmap element */
+
+static INLINE void
+bitmap_element_free (head, elt)
+     bitmap head;
+     bitmap_element *elt;
+{
+  bitmap_element *next = elt->next;
+  bitmap_element *prev = elt->prev;
+
+  if (prev)
+    prev->next = next;
+
+  if (next)
+    next->prev = prev;
+
+  if (head->first == elt)
+    head->first = next;
+
+  /* Since the first thing we try is to insert before current,
+     make current the next entry in preference to the previous.  */
+  if (head->current == elt)
+    head->current = next != 0 ? next : prev;
+
+  elt->next = bitmap_free;
+  bitmap_free = elt;
+}
+
+/* Allocate a bitmap element.  The bits are cleared, but nothing else is.  */
+
+static INLINE bitmap_element *
+bitmap_element_allocate (head)
+     bitmap head;
+{
+  bitmap_element *element;
+  int i;
+
+  if (bitmap_free != 0)
+    {
+      element = bitmap_free;
+      bitmap_free = element->next;
+    }
+  else
+    element = (bitmap_element *) obstack_alloc (function_obstack,
+						sizeof (bitmap_element));
+
+#if BITMAP_ELEMENT_WORDS == 2
+  element->bits[0] = element->bits[1] = 0;
+#else
+  for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
+    element->bits[i] = 0;
+#endif
+
+  return element;
+}
+
+/* Return nonzero if all bits in an element are zero.  */
+
+static INLINE int
+bitmap_element_zerop (element)
+     bitmap_element *element;
+{
+#if BITMAP_ELEMENT_WORDS == 2
+  return (element->bits[0] | element->bits[1]) == 0;
+#else
+  int i;
+
+  for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
+    if (element->bits[i] != 0)
+      return 0;
+
+  return 1;
+#endif
+}
+
+/* Link the bitmap element into the current bitmap linked list.  */
+
+static INLINE void
+bitmap_element_link (head, element)
+     bitmap head;
+     bitmap_element *element;
+{
+  unsigned int indx = element->indx;
+  bitmap_element *ptr;
+
+  /* If this is the first and only element, set it in.  */
+  if (head->first == 0)
+    {
+      element->next = element->prev = 0;
+      head->first = element;
+    }
+
+  /* If this index is less than that of the current element, it goes someplace
+     before the current element.  */
+  else if (indx < head->indx)
+    {
+      for (ptr = head->current;
+	   ptr->prev != 0 && ptr->prev->indx > indx;
+	   ptr = ptr->prev)
+	;
+
+      if (ptr->prev)
+	ptr->prev->next = element;
+      else
+	head->first = element;
+
+      element->prev = ptr->prev;
+      element->next = ptr;
+      ptr->prev = element;
+    }
+
+  /* Otherwise, it must go someplace after the current element.  */
+  else
+    {
+      for (ptr = head->current;
+	   ptr->next != 0 && ptr->next->indx < indx;
+	   ptr = ptr->next)
+	;
+
+      if (ptr->next)
+	ptr->next->prev = element;
+
+      element->next = ptr->next;
+      element->prev = ptr;
+      ptr->next = element;
+    }
+
+  /* Set up so this is the first element searched.  */
+  head->current = element;
+  head->indx = indx;
+}
+
+/* Clear a bitmap by freeing the linked list.  */
+
+void INLINE
+bitmap_clear (head)
+     bitmap head;
+{
+  bitmap_element *element, *next;
+
+  for (element = head->first; element != 0; element = next)
+    {
+      next = element->next;
+      element->next = bitmap_free;
+      bitmap_free = element;
+    }
+
+  head->first = head->current =  0;
+}
+
+/* Copy a bitmap to another bitmap */
+
+void
+bitmap_copy (to, from)
+     bitmap to;
+     bitmap from;
+{
+  bitmap_element *from_ptr, *to_ptr = 0;
+  int i;
+
+  bitmap_clear (to);
+
+  /* Copy elements in forward direction one at a time */
+  for (from_ptr = from->first; from_ptr; from_ptr = from_ptr->next)
+    {
+      bitmap_element *to_elt = bitmap_element_allocate (to);
+
+      to_elt->indx = from_ptr->indx;
+
+#if BITMAP_ELEMENT_WORDS == 2
+      to_elt->bits[0] = from_ptr->bits[0];
+      to_elt->bits[1] = from_ptr->bits[1];
+#else
+      for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
+	to_elt->bits[i] = from_ptr->bits[i];
+#endif
+
+      /* Here we have a special case of bitmap_element_link, for the case
+	 where we know the links are being entered in sequence.  */
+      if (to_ptr == 0)
+	{
+	  to->first = to->current = to_elt;
+	  to->indx = from_ptr->indx;
+	  to_elt->next = to_elt->prev = 0;
+	}
+      else
+	{
+	  to_elt->prev = to_ptr;
+	  to_elt->next = 0;
+	  to_ptr->next = to_elt;
+	}
+
+      to_ptr = to_elt;
+    }
+}
+
+/* Find a bitmap element that would hold a bitmap's bit.
+   Update the `current' field even if we can't find an element that
+   would hold the bitmap's bit to make eventual allocation
+   faster.  */
+
+static INLINE bitmap_element *
+bitmap_find_bit (head, bit)
+     bitmap head;
+     unsigned int bit;
+{
+  bitmap_element *element;
+  unsigned HOST_WIDE_INT indx = bit / BITMAP_ELEMENT_ALL_BITS;
+
+  if (head->current == 0)
+    return 0;
+
+  if (head->indx > indx)
+    for (element = head->current;
+	 element->prev != 0 && element->indx > indx;
+	 element = element->prev)
+      ;
+
+  else
+    for (element = head->current;
+	 element->next != 0 && element->indx < indx;
+	 element = element->next)
+      ;
+
+  /* `element' is the nearest to the one we want.  If it's not the one we
+     want, the one we want doesn't exist.  */
+  head->current = element;
+  head->indx = element->indx;
+  if (element != 0 && element->indx != indx)
+    element = 0;
+
+  return element;
+}
+
+/* Clear a single bit in a bitmap.  */
+
+void
+bitmap_clear_bit (head, bit)
+     bitmap head;
+     int bit;
+{
+  bitmap_element *ptr = bitmap_find_bit (head, bit);
+
+  if (ptr != 0)
+    {
+      unsigned bit_num  = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
+      unsigned word_num = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT)
+			   % BITMAP_ELEMENT_WORDS);
+      ptr->bits[word_num] &= ~ (((unsigned HOST_WIDE_INT) 1) << bit_num);
+
+      /* If we cleared the entire word, free up the element */
+      if (bitmap_element_zerop (ptr))
+	bitmap_element_free (head, ptr);
+    }
+}
+
+
+/* Set a single bit in a bitmap.  */
+
+void
+bitmap_set_bit (head, bit)
+     bitmap head;
+     int bit;
+{
+  bitmap_element *ptr = bitmap_find_bit (head, bit);
+  unsigned word_num
+    = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT) % BITMAP_ELEMENT_WORDS);
+  unsigned bit_num  = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
+  unsigned HOST_WIDE_INT bit_val = ((unsigned HOST_WIDE_INT) 1) << bit_num;
+
+  if (ptr == 0)
+    {
+      ptr = bitmap_element_allocate (head);
+      ptr->indx = bit / BITMAP_ELEMENT_ALL_BITS;
+      ptr->bits[word_num] = bit_val;
+      bitmap_element_link (head, ptr);
+    }
+  else
+    ptr->bits[word_num] |= bit_val;
+}
+
+/* Return whether a bit is set within a bitmap.  */
+
+int
+bitmap_bit_p (head, bit)
+     bitmap head;
+     int bit;
+{
+  bitmap_element *ptr;
+  unsigned bit_num;
+  unsigned word_num;
+
+  ptr = bitmap_find_bit (head, bit);
+  if (ptr == 0)
+    return 0;
+
+  bit_num = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
+  word_num
+    = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT) % BITMAP_ELEMENT_WORDS);
+
+  return
+    (ptr->bits[word_num] & (((unsigned HOST_WIDE_INT) 1) << bit_num)) != 0;
+}
+
+/* Store in bitmap TO the result of combining bitmap FROM1 and
+   FROM2 using a specific bit manipulation.  */
+
+void
+bitmap_operation (to, from1, from2, operation)
+     bitmap to;
+     bitmap from1;
+     bitmap from2;
+     enum bitmap_bits operation;
+{
+  bitmap_element *delete_list = 0;
+  bitmap_element *from1_ptr = from1->first;
+  bitmap_element *from2_ptr = from2->first;
+  unsigned int indx1
+    = (from1_ptr) ? from1_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
+  unsigned int indx2
+    = (from2_ptr) ? from2_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
+  bitmap_element *to_ptr = 0;
+  bitmap_element *from1_tmp;
+  bitmap_element *from2_tmp;
+  unsigned int indx;
+  int i;
+
+  /* To simplify things, always create a new list.  If the old list was one
+     of the inputs, free it later.  Otherwise, free it now.  */
+  if (to == from1 || to == from2)
+    {
+      delete_list = to->first;
+      to->first = 0;
+    }
+  else
+    bitmap_clear (to);
+
+  while (from1_ptr != 0 || from2_ptr != 0)
+    {
+      /* Figure out whether we need to substitute zero elements for
+	 missing links.  */
+      if (indx1 == indx2)
+	{
+	  indx = indx1;
+	  from1_tmp = from1_ptr;
+	  from2_tmp = from2_ptr;
+	  from1_ptr = from1_ptr->next;
+	  indx1 = (from1_ptr) ? from1_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
+	  from2_ptr = from2_ptr->next;
+	  indx2 = (from2_ptr) ? from2_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
+	}
+      else if (indx1 < indx2)
+	{
+	  indx = indx1;
+	  from1_tmp = from1_ptr;
+	  from2_tmp = &bitmap_zero;
+	  from1_ptr = from1_ptr->next;
+	  indx1 = (from1_ptr) ? from1_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
+	}
+      else
+	{
+	  indx = indx2;
+	  from1_tmp = &bitmap_zero;
+	  from2_tmp = from2_ptr;
+	  from2_ptr = from2_ptr->next;
+	  indx2 = (from2_ptr) ? from2_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
+	}
+
+      if (to_ptr == 0)
+	to_ptr = bitmap_element_allocate (to);
+
+      /* Do the operation, and if any bits are set, link it into the
+	 linked list.  */
+      switch (operation)
+	{
+	default:
+	  abort ();
+
+	case BITMAP_AND:
+#if BITMAP_ELEMENT_WORDS == 2
+	  to_ptr->bits[0] = from1_tmp->bits[0] & from2_tmp->bits[0];
+	  to_ptr->bits[1] = from1_tmp->bits[1] & from2_tmp->bits[1];
+#else
+	  for (i = BITMAP_ELEMENT_WORDS - 1; i >= 0; i--)
+	    to_ptr->bits[i] = from1_tmp->bits[i] & from2_tmp->bits[i];
+#endif
+	  break;
+
+	case BITMAP_AND_COMPL:
+#if BITMAP_ELEMENT_WORDS == 2
+	  to_ptr->bits[0] = from1_tmp->bits[0] & ~ from2_tmp->bits[0];
+	  to_ptr->bits[1] = from1_tmp->bits[1] & ~ from2_tmp->bits[1];
+#else
+	  for (i = BITMAP_ELEMENT_WORDS - 1; i >= 0; i--)
+	    to_ptr->bits[i] = from1_tmp->bits[i] & ~ from2_tmp->bits[i];
+#endif
+	  break;
+
+	case BITMAP_IOR:
+#if BITMAP_ELEMENT_WORDS == 2
+	  to_ptr->bits[0] = from1_tmp->bits[0] | from2_tmp->bits[0];
+	  to_ptr->bits[1] = from1_tmp->bits[1] | from2_tmp->bits[1];
+#else
+	  for (i = BITMAP_ELEMENT_WORDS - 1; i >= 0; i--)
+	    to_ptr->bits[i] = from1_tmp->bits[i] | from2_tmp->bits[i];
+#endif
+	  break;
+	}
+
+      if (! bitmap_element_zerop (to_ptr))
+	{
+	  to_ptr->indx = indx;
+	  bitmap_element_link (to, to_ptr);
+	  to_ptr = 0;
+	}
+    }
+
+  /* If we have an unallocated element due to the last element being 0,
+     release it back to the free pool.  Don't bother calling
+     bitmap_element_free since it was never linked into a bitmap.  */
+  if (to_ptr != 0)
+    {
+      to_ptr->next = bitmap_free;
+      bitmap_free = to_ptr;
+    }
+
+  /* If the output bitmap was one of the inputs, free up its
+     elements now that we're done.  */
+  for (; delete_list != 0; delete_list = to_ptr)
+    {
+      to_ptr = delete_list->next;
+      delete_list->next = bitmap_free;
+      bitmap_free = delete_list;
+    }
+}
+
+/* Or into bitmap TO bitmap FROM1 and'ed with the complement of
+   bitmap FROM2. */
+
+void
+bitmap_ior_and_compl (to, from1, from2)
+     bitmap to;
+     bitmap from1;
+     bitmap from2;
+{
+  bitmap_head tmp;
+
+  tmp.first = tmp.current = 0;
+
+  bitmap_operation (&tmp, from1, from2, BITMAP_AND_COMPL);
+  bitmap_operation (to, to, &tmp, BITMAP_IOR);
+  bitmap_clear (&tmp);
+}
+
+/* Initialize a bitmap header.  */
+
+bitmap
+bitmap_initialize (head)
+     bitmap head;
+{
+  head->first = head->current = 0;
+
+  return head;
+}
+
+/* Debugging function to print out the contents of a bitmap.  */
+
+void
+bitmap_debug_file (file, head)
+     FILE *file;
+     bitmap head;
+{
+  bitmap_element *ptr;
+
+  fprintf (file, "\nfirst = ");
+  fprintf (file, HOST_PTR_PRINTF, (HOST_WIDE_INT) head->first);
+  fprintf (file, " current = ");
+  fprintf (file, HOST_PTR_PRINTF, (HOST_WIDE_INT) head->current);
+  fprintf (file, " indx = %u\n", head->indx);
+
+  for (ptr = head->first; ptr; ptr = ptr->next)
+    {
+      int i, j, col = 26;
+
+      fprintf (file, "\t");
+      fprintf (file, HOST_PTR_PRINTF, (HOST_WIDE_INT) ptr);
+      fprintf (file, " next = ");
+      fprintf (file, HOST_PTR_PRINTF, (HOST_WIDE_INT) ptr->next);
+      fprintf (file, " prev = ");
+      fprintf (file, HOST_PTR_PRINTF, (HOST_WIDE_INT) ptr->prev);
+      fprintf (file, " indx = %u\n\t\tbits = {", ptr->indx);
+
+      for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
+	for (j = 0; j < HOST_BITS_PER_WIDE_INT; j++)
+	  if ((ptr->bits[i] & (((unsigned HOST_WIDE_INT) 1) << j)) != 0)
+	    {
+	      if (col > 70)
+		{
+		  fprintf (file, "\n\t\t\t");
+		  col = 24;
+		}
+
+	      fprintf (file, " %u", (ptr->indx * BITMAP_ELEMENT_ALL_BITS
+				     + i * HOST_BITS_PER_WIDE_INT + j));
+	      col += 4;
+	    }
+
+      fprintf (file, " }\n");
+    }
+}
+
+/* Function to be called from the debugger to print the contents
+   of a bitmap.  */
+
+void
+debug_bitmap (head)
+     bitmap head;
+{
+  bitmap_debug_file (stdout, head);
+}
+
+/* Release any memory allocated by bitmaps.  Since we allocate off of the
+   function_obstack, just zap the free list.  */
+
+void
+bitmap_release_memory ()
+{
+  bitmap_free = 0;
+}