* java/lang/natString.cc (_Jv_NewStringUtf8Const): Register finalizer.

	Recalculate hash, since Utf8Const's hash is only 16 bits.

	* java/lang/natString.cc (_Jv_StringFindSlot, rehash):  Use high-order
	bits of hash to calculate step for chaining.

	* java/lang/natString.cc (intern, _Jv_NewStringUtf8Const):  Rehash
	when 2/3 full, rather than 3/4 full.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@41233 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/libjava/ChangeLog b/libjava/ChangeLog
index b68b23a..3d2ae9d 100644 (file)
--- a/libjava/ChangeLog
+++ b/libjava/ChangeLog
@@ -1,3 +1,14 @@
+2001-04-08  Per Bothner  <per@bothner.com>
+
+       * java/lang/natString.cc (_Jv_NewStringUtf8Const):  Register finalizer.
+       Recalculate hash, since Utf8Const's hash is only 16 bits.
+
+       * java/lang/natString.cc (_Jv_StringFindSlot, rehash):  Use high-order
+       bits of hash to calculate step for chaining.
+
+       * java/lang/natString.cc (intern, _Jv_NewStringUtf8Const):  Rehash
+       when 2/3 full, rather than 3/4 full.
+
 2001-04-06  Tom Tromey  <tromey@redhat.com>
 
        * jni.cc (wrap_value<jobject>, wrap_value<jclass>): Removed.

diff --git a/libjava/java/lang/natString.cc b/libjava/java/lang/natString.cc
index 1c71bfd..be0c91c 100644 (file)
--- a/libjava/java/lang/natString.cc
+++ b/libjava/java/lang/natString.cc
@@ -62,7 +62,7 @@ _Jv_StringFindSlot (jchar* data, jint len, jint hash)
 
   int index = start_index;
   /* step must be non-zero, and relatively prime with strhash_size. */
-  int step = 8 * hash + 7;
+  jint step = (hash ^ (hash >> 16)) | 1;
   for (;;)
     {
       jstring* ptr = &strhash[index];
@@ -145,7 +145,7 @@ java::lang::String::rehash()
          jstring val = (jstring) UNMASK_PTR (*ptr);
          jint hash = val->hashCode();
          jint index = hash & (nsize - 1);
-         jint step = 8 * hash + 7;
+         jint step = (hash ^ (hash >> 16)) | 1;
          for (;;)
            {
              if (next[index] == NULL)
@@ -166,7 +166,7 @@ jstring
 java::lang::String::intern()
 {
   JvSynchronize sync (&StringClass);
-  if (4 * strhash_count >= 3 * strhash_size)
+  if (3 * strhash_count >= 2 * strhash_size)
     rehash();
   jstring* ptr = _Jv_StringGetSlot(this);
   if (*ptr != NULL && *ptr != DELETED_STRING)
@@ -265,14 +265,18 @@ _Jv_NewStringUtf8Const (Utf8Const* str)
       chrs = JvGetStringChars(jstr);
     }
 
+  jint hash = 0;
   while (data < limit)
-    *chrs++ = UTF8_GET(data, limit);
+    {
+      jchar ch = UTF8_GET(data, limit);
+      hash = (31 * hash) + ch;
+      *chrs++ = ch;
+    }
   chrs -= length;
 
   JvSynchronize sync (&StringClass);
-  if (4 * strhash_count >= 3 * strhash_size)
+  if (3 * strhash_count >= 2 * strhash_size)
     java::lang::String::rehash();
-  int hash = str->hash;
   jstring* ptr = _Jv_StringFindSlot (chrs, length, hash);
   if (*ptr != NULL && *ptr != DELETED_STRING)
     return (jstring) UNMASK_PTR (*ptr);
@@ -285,6 +289,8 @@ _Jv_NewStringUtf8Const (Utf8Const* str)
     }
   *ptr = jstr;
   SET_STRING_IS_INTERNED(jstr);
+  // When string is GC'd, clear the slot in the hash table.
+  _Jv_RegisterFinalizer ((void *) jstr, unintern);
   return jstr;
 }