hashtab.c (higher_prime_number): Use 7 as minimum.

        * hashtab.c (higher_prime_number): Use 7 as minimum.
        (find_empty_slot_for_expand): Don't compute hash2 unless needed.
        (htab_find_slot_with_hash): Likewise.

From-SVN: r52099

libiberty/ChangeLog

+2002-04-09  Richard Henderson  <rth@redhat.com>
+
+	* hashtab.c (higher_prime_number): Use 7 as minimum.
+	(find_empty_slot_for_expand): Don't compute hash2 unless needed.
+	(htab_find_slot_with_hash): Likewise.
+
 2002-04-01  Phil Edwards  <pme@gcc.gnu.org>
 
 	* cp-demangle.c (__cxa_demangle):  Also protect with IN_GLIBCPP_V3.

libiberty/hashtab.c

 /* An expandable hash tables datatype.  
-   Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.
+   Copyright (C) 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
    Contributed by Vladimir Makarov (vmakarov@cygnus.com).
 
 This file is part of the libiberty library.
@@ -81,7 +81,6 @@ higher_prime_number (n)
   /* These are primes that are near, but slightly smaller than, a
      power of two.  */
   static const unsigned long primes[] = {
-    (unsigned long) 2,
     (unsigned long) 7,
     (unsigned long) 13,
     (unsigned long) 31,
@@ -264,21 +263,27 @@ find_empty_slot_for_expand (htab, hash)
      hashval_t hash;
 {
   size_t size = htab->size;
-  hashval_t hash2 = 1 + hash % (size - 2);
   unsigned int index = hash % size;
+  PTR *slot = htab->entries + index;
+  hashval_t hash2;
+
+  if (*slot == EMPTY_ENTRY)
+    return slot;
+  else if (*slot == DELETED_ENTRY)
+    abort ();
 
+  hash2 = 1 + hash % (size - 2);
   for (;;)
     {
-      PTR *slot = htab->entries + index;
+      index += hash2;
+      if (index >= size)
+	index -= size;
 
+      slot = htab->entries + index;
       if (*slot == EMPTY_ENTRY)
 	return slot;
       else if (*slot == DELETED_ENTRY)
 	abort ();
-
-      index += hash2;
-      if (index >= size)
-	index -= size;
     }
 }
 
@@ -405,50 +410,59 @@ htab_find_slot_with_hash (htab, element, hash, insert)
   unsigned int index;
   hashval_t hash2;
   size_t size;
+  PTR entry;
 
   if (insert == INSERT && htab->size * 3 <= htab->n_elements * 4
       && htab_expand (htab) == 0)
     return NULL;
 
   size = htab->size;
-  hash2 = 1 + hash % (size - 2);
   index = hash % size;
 
   htab->searches++;
   first_deleted_slot = NULL;
 
+  entry = htab->entries[index];
+  if (entry == EMPTY_ENTRY)
+    goto empty_entry;
+  else if (entry == DELETED_ENTRY)
+    first_deleted_slot = &htab->entries[index];
+  else if ((*htab->eq_f) (entry, element))
+    return &htab->entries[index];
+      
+  hash2 = 1 + hash % (size - 2);
   for (;;)
     {
-      PTR entry = htab->entries[index];
+      htab->collisions++;
+      index += hash2;
+      if (index >= size)
+	index -= size;
+      
+      entry = htab->entries[index];
       if (entry == EMPTY_ENTRY)
-	{
-	  if (insert == NO_INSERT)
-	    return NULL;
-
-	  htab->n_elements++;
-
-	  if (first_deleted_slot)
-	    {
-	      *first_deleted_slot = EMPTY_ENTRY;
-	      return first_deleted_slot;
-	    }
-
-	  return &htab->entries[index];
-	}
-
-      if (entry == DELETED_ENTRY)
+	goto empty_entry;
+      else if (entry == DELETED_ENTRY)
 	{
 	  if (!first_deleted_slot)
 	    first_deleted_slot = &htab->entries[index];
 	}
-      else  if ((*htab->eq_f) (entry, element))
+      else if ((*htab->eq_f) (entry, element))
 	return &htab->entries[index];
-      
-      htab->collisions++;
-      index += hash2;
-      if (index >= size)
-	index -= size;
     }
+
+ empty_entry:
+  if (insert == NO_INSERT)
+    return NULL;
+
+  htab->n_elements++;
+
+  if (first_deleted_slot)
+    {
+      *first_deleted_slot = EMPTY_ENTRY;
+      return first_deleted_slot;
+    }
+
+  return &htab->entries[index];
 }
 
 /* Like htab_find_slot_with_hash, but compute the hash value from the