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[pf3gnuchains/gcc-fork.git] / gcc / pointer-set.c

diff --git a/gcc/pointer-set.c b/gcc/pointer-set.c
index 3f79cc2..266cccf 100644 (file)
--- a/gcc/pointer-set.c
+++ b/gcc/pointer-set.c
@@ -90,6 +90,29 @@ void pointer_set_destroy (struct pointer_set_t *pset)
   XDELETE (pset);
 }
 
+/* Returns nonzero if PSET contains P.  P must be nonnull.
+
+   Collisions are resolved by linear probing.  */
+int
+pointer_set_contains (struct pointer_set_t *pset, void *p)
+{
+  size_t n = hash1 (p, pset->n_slots, pset->log_slots);
+
+  while (true)
+    {
+      if (pset->slots[n] == p)
+       return 1;
+      else if (pset->slots[n] == 0)
+       return 0;
+      else
+       {
+         ++n;
+         if (n == pset->n_slots)
+           n = 0;
+       }
+    }
+}
+
 /* Subroutine of pointer_set_insert.  Inserts P into an empty
    element of SLOTS, an array of length N_SLOTS.  Returns nonzero
    if P was already present in N_SLOTS.  */