hashtable.c (ht_expand): Avoid calculating rehash for the common case that the first probe hits an empty...

	* hashtable.c (ht_expand): Avoid calculating rehash for the common
	case that the first probe hits an empty hash table slot.

From-SVN: r70706

2 files changed, 11 insertions, 7 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 3dd61eb..f97afe2 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2003-08-22  Roger Sayle  <roger@eyesopen.com>
+
+	* hashtable.c (ht_expand): Avoid calculating rehash for the common
+	case that the first probe hits an empty hash table slot.
+
 2003-08-22  Mark Mitchell  <mark@codesourcery.com>
 
 	* config/ia64/hpux.h (SUPPORTS_INIT_PRIORITY): Define to 0.
diff --git a/gcc/hashtable.c b/gcc/hashtable.c
index 4155139..58f19d0 100644
--- a/gcc/hashtable.c
+++ b/gcc/hashtable.c
@@ -184,19 +184,18 @@ ht_expand (hash_table *table)
 	unsigned int index, hash, hash2;
 
 	hash = (*p)->hash_value;
-	hash2 = ((hash * 17) & sizemask) | 1;
 	index = hash & sizemask;
 
-	for (;;)
+	if (nentries[index])
 	  {
-	    if (! nentries[index])
+	    hash2 = ((hash * 17) & sizemask) | 1;
+	    do
 	      {
-		nentries[index] = *p;
-		break;
+		index = (index + hash2) & sizemask;
 	      }
-
-	    index = (index + hash2) & sizemask;
+	    while (nentries[index]);
 	  }
+	nentries[index] = *p;
       }
   while (++p < limit);