/* Functions to support general ended bitmaps.
- Copyright (C) 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
+ Copyright (C) 1997, 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
This file is part of GNU CC.
#endif
/* Global data */
-bitmap_element bitmap_zero; /* An element of all zero bits. */
-bitmap_element *bitmap_free; /* Freelist of bitmap elements. */
+bitmap_element bitmap_zero_bits; /* An element of all zero bits. */
+static bitmap_element *bitmap_free; /* Freelist of bitmap elements. */
static void bitmap_element_free PARAMS ((bitmap, bitmap_element *));
static bitmap_element *bitmap_element_allocate PARAMS ((void));
static void bitmap_element_link PARAMS ((bitmap, bitmap_element *));
static bitmap_element *bitmap_find_bit PARAMS ((bitmap, unsigned int));
\f
-/* Free a bitmap element */
+/* Free a bitmap element. Since these are allocated off the
+ bitmap_obstack, "free" actually means "put onto the freelist". */
static INLINE void
bitmap_element_free (head, elt)
bitmap_element_allocate ()
{
bitmap_element *element;
-#if BITMAP_ELEMENT_WORDS != 2
- int i;
-#endif
if (bitmap_free != 0)
{
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
+ memset (element->bits, 0, sizeof (element->bits));
return element;
}
+/* Release any memory allocated by bitmaps. */
+
+void
+bitmap_release_memory ()
+{
+ bitmap_free = 0;
+ if (bitmap_obstack_init)
+ {
+ bitmap_obstack_init = FALSE;
+ obstack_free (&bitmap_obstack, NULL);
+ }
+}
+
/* Return nonzero if all bits in an element are zero. */
static INLINE int
head->first = head->current = 0;
}
\f
-/* Copy a bitmap to another bitmap */
+/* Copy a bitmap to another bitmap. */
void
bitmap_copy (to, from)
}
}
-\f
/* Set a single bit in a bitmap. */
void
else
ptr->bits[word_num] |= bit_val;
}
-\f
+
/* Return whether a bit is set within a bitmap. */
int
return (ptr->bits[word_num] >> bit_num) & 1;
}
\f
+/* Return the bit number of the first set bit in the bitmap, or -1
+ if the bitmap is empty. */
+
+int
+bitmap_first_set_bit (a)
+ bitmap a;
+{
+ bitmap_element *ptr = a->first;
+ unsigned HOST_WIDE_INT word;
+ unsigned word_num, bit_num;
+
+ if (ptr == NULL)
+ return -1;
+
+#if BITMAP_ELEMENT_WORDS == 2
+ word_num = 0, word = ptr->bits[0];
+ if (word == 0)
+ word_num = 1, word = ptr->bits[1];
+#else
+ for (word_num = 0; word_num < BITMAP_ELEMENT_WORDS; ++word_num)
+ if ((word = ptr->bits[word_num]) != 0)
+ break;
+#endif
+
+ /* Binary search for the first set bit. */
+ /* ??? It'd be nice to know if ffs or ffsl was available. */
+
+ bit_num = 0;
+ word = word & -word;
+
+#if HOST_BITS_PER_WIDE_INT > 64
+ #error "Fill out the table."
+#endif
+#if HOST_BITS_PER_WIDE_INT > 32
+ if ((word & 0xffffffff) == 0)
+ word >>= 32, bit_num += 32;
+#endif
+ if ((word & 0xffff) == 0)
+ word >>= 16, bit_num += 16;
+ if ((word & 0xff) == 0)
+ word >>= 8, bit_num += 8;
+ if (word & 0xf0)
+ bit_num += 4;
+ if (word & 0xcc)
+ bit_num += 2;
+ if (word & 0xaa)
+ bit_num += 1;
+
+ return (ptr->indx * BITMAP_ELEMENT_ALL_BITS
+ + word_num * HOST_BITS_PER_WIDE_INT
+ + bit_num);
+}
+
+/* Return the bit number of the last set bit in the bitmap, or -1
+ if the bitmap is empty. */
+
+int
+bitmap_last_set_bit (a)
+ bitmap a;
+{
+ bitmap_element *ptr = a->first;
+ unsigned HOST_WIDE_INT word;
+ unsigned word_num, bit_num;
+
+ if (ptr == NULL)
+ return -1;
+
+ while (ptr->next != NULL)
+ ptr = ptr->next;
+
+#if BITMAP_ELEMENT_WORDS == 2
+ word_num = 1, word = ptr->bits[1];
+ if (word == 0)
+ word_num = 0, word = ptr->bits[0];
+#else
+ for (word_num = BITMAP_ELEMENT_WORDS; word_num-- > 0; )
+ if ((word = ptr->bits[word_num]) != 0)
+ break;
+#endif
+
+ /* Binary search for the last set bit. */
+
+ bit_num = 0;
+#if HOST_BITS_PER_WIDE_INT > 64
+ #error "Fill out the table."
+#endif
+#if HOST_BITS_PER_WIDE_INT > 32
+ if (word & ~ (unsigned HOST_WIDE_INT) 0xffffffff)
+ word >>= 32, bit_num += 32;
+#endif
+ if (word & 0xffff0000)
+ word >>= 16, bit_num += 16;
+ if (word & 0xff00)
+ word >>= 8, bit_num += 8;
+ if (word & 0xf0)
+ word >>= 4, bit_num += 4;
+ if (word & 0xc)
+ word >>= 2, bit_num += 2;
+ if (word & 0x2)
+ bit_num += 1;
+
+ return (ptr->indx * BITMAP_ELEMENT_ALL_BITS
+ + word_num * HOST_BITS_PER_WIDE_INT
+ + bit_num);
+}
+\f
/* Store in bitmap TO the result of combining bitmap FROM1 and FROM2 using
a specific bit manipulation. Return true if TO changes. */
{
indx = indx1;
from1_tmp = from1_ptr;
- from2_tmp = &bitmap_zero;
+ from2_tmp = &bitmap_zero_bits;
from1_ptr = from1_ptr->next;
indx1 = (from1_ptr) ? from1_ptr->indx : HIGHEST_INDEX;
}
else
{
indx = indx2;
- from1_tmp = &bitmap_zero;
+ from1_tmp = &bitmap_zero_bits;
from2_tmp = from2_ptr;
from2_ptr = from2_ptr->next;
indx2 = (from2_ptr) ? from2_ptr->indx : HIGHEST_INDEX;
}
/* Find the appropriate element from TO. Begin by discarding
- elements that we've skipped. */
+ elements that we've skipped. */
while (to_ptr && to_ptr->indx < indx)
{
changed = 1;
}
\f
/* Or into bitmap TO bitmap FROM1 and'ed with the complement of
- bitmap FROM2. */
+ bitmap FROM2. */
void
bitmap_ior_and_compl (to, from1, from2)
bitmap_operation (to, to, &tmp, BITMAP_IOR);
bitmap_clear (&tmp);
}
+
+int
+bitmap_union_of_diff (dst, a, b, c)
+ bitmap dst;
+ bitmap a;
+ bitmap b;
+ bitmap c;
+{
+ bitmap_head tmp;
+ int changed;
+
+ tmp.first = tmp.current = 0;
+
+ bitmap_operation (&tmp, b, c, BITMAP_AND_COMPL);
+ changed = bitmap_operation (dst, &tmp, a, BITMAP_IOR);
+ bitmap_clear (&tmp);
+
+ return changed;
+}
\f
/* Initialize a bitmap header. */
fprintf (file, " }\n");
}
}
-\f
+
/* Function to be called from the debugger to print the contents
of a bitmap. */
{
debug_bitmap_file (stdout, head);
}
-\f
+
/* Function to print out the contents of a bitmap. Unlike debug_bitmap_file,
it does not print anything but the bits. */
});
fputs (suffix, file);
}
-\f
-/* Release any memory allocated by bitmaps. */
-
-void
-bitmap_release_memory ()
-{
- bitmap_free = 0;
- if (bitmap_obstack_init)
- {
- bitmap_obstack_init = FALSE;
- obstack_free (&bitmap_obstack, NULL);
- }
-}
-
-int
-bitmap_union_of_diff (dst, a, b, c)
- bitmap dst;
- bitmap a;
- bitmap b;
- bitmap c;
-{
- int changed = 0;
- bitmap temp = BITMAP_ALLOCA ();
- bitmap_operation (temp, b, c, BITMAP_AND_COMPL);
- changed = bitmap_operation (dst, temp, a, BITMAP_IOR);
- return changed;
-}
-
-int
-bitmap_first_set_bit (a)
- bitmap a;
-{
- int i;
- EXECUTE_IF_SET_IN_BITMAP (a, 0, i, return i;);
- return -1;
-}
-
-int
-bitmap_last_set_bit (a)
- bitmap a;
-{
- int i;
- EXECUTE_IF_SET_IN_BITMAP (a, 0, i, );
- if (bitmap_bit_p (a, i))
- return i;
- return -1;
-}
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