+/* Structure used to put solution bitmaps in a hashtable so they can
+ be shared among variables with the same points-to set. */
+
+typedef struct shared_bitmap_info
+{
+ bitmap pt_vars;
+ hashval_t hashcode;
+} *shared_bitmap_info_t;
+
+static htab_t shared_bitmap_table;
+
+/* Hash function for a shared_bitmap_info_t */
+
+static hashval_t
+shared_bitmap_hash (const void *p)
+{
+ const shared_bitmap_info_t bi = (shared_bitmap_info_t) p;
+ return bi->hashcode;
+}
+
+/* Equality function for two shared_bitmap_info_t's. */
+
+static int
+shared_bitmap_eq (const void *p1, const void *p2)
+{
+ const shared_bitmap_info_t sbi1 = (shared_bitmap_info_t) p1;
+ const shared_bitmap_info_t sbi2 = (shared_bitmap_info_t) p2;
+ return bitmap_equal_p (sbi1->pt_vars, sbi2->pt_vars);
+}
+
+/* Lookup a bitmap in the shared bitmap hashtable, and return an already
+ existing instance if there is one, NULL otherwise. */
+
+static bitmap
+shared_bitmap_lookup (bitmap pt_vars)
+{
+ void **slot;
+ struct shared_bitmap_info sbi;
+
+ sbi.pt_vars = pt_vars;
+ sbi.hashcode = bitmap_hash (pt_vars);
+
+ slot = htab_find_slot_with_hash (shared_bitmap_table, &sbi,
+ sbi.hashcode, NO_INSERT);
+ if (!slot)
+ return NULL;
+ else
+ return ((shared_bitmap_info_t) *slot)->pt_vars;
+}
+
+
+/* Add a bitmap to the shared bitmap hashtable. */
+
+static void
+shared_bitmap_add (bitmap pt_vars)
+{
+ void **slot;
+ shared_bitmap_info_t sbi = XNEW (struct shared_bitmap_info);
+
+ sbi->pt_vars = pt_vars;
+ sbi->hashcode = bitmap_hash (pt_vars);
+
+ slot = htab_find_slot_with_hash (shared_bitmap_table, sbi,
+ sbi->hashcode, INSERT);
+ gcc_assert (!*slot);
+ *slot = (void *) sbi;
+}
+
+