src/hotspot/share/classfile/compactHashtable.inline.hpp
changeset 47216 71c04702a3d5
parent 37995 92aec042a43b
child 49592 77fb0be7d19f
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/classfile/compactHashtable.inline.hpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_VM_CLASSFILE_COMPACTHASHTABLE_INLINE_HPP
+#define SHARE_VM_CLASSFILE_COMPACTHASHTABLE_INLINE_HPP
+
+#include "classfile/compactHashtable.hpp"
+#include "memory/allocation.inline.hpp"
+#include "oops/oop.inline.hpp"
+
+template <class T, class N>
+inline Symbol* CompactHashtable<T, N>::decode_entry(CompactHashtable<Symbol*, char>* const t,
+                                                    u4 offset, const char* name, int len) {
+  Symbol* sym = (Symbol*)(_base_address + offset);
+  if (sym->equals(name, len)) {
+    assert(sym->refcount() == -1, "must be shared");
+    return sym;
+  }
+
+  return NULL;
+}
+
+template <class T, class N>
+inline oop CompactHashtable<T, N>::decode_entry(CompactHashtable<oop, char>* const t,
+                                                u4 offset, const char* name, int len) {
+  narrowOop obj = (narrowOop)offset;
+  oop string = oopDesc::decode_heap_oop(obj);
+  if (java_lang_String::equals(string, (jchar*)name, len)) {
+    return string;
+  }
+
+  return NULL;
+}
+
+template <class T, class N>
+inline T CompactHashtable<T,N>::lookup(const N* name, unsigned int hash, int len) {
+  if (_entry_count > 0) {
+    int index = hash % _bucket_count;
+    u4 bucket_info = _buckets[index];
+    u4 bucket_offset = BUCKET_OFFSET(bucket_info);
+    int bucket_type = BUCKET_TYPE(bucket_info);
+    u4* entry = _entries + bucket_offset;
+
+    if (bucket_type == VALUE_ONLY_BUCKET_TYPE) {
+      T res = decode_entry(this, entry[0], name, len);
+      if (res != NULL) {
+        return res;
+      }
+    } else {
+      // This is a regular bucket, which has more than one
+      // entries. Each entry is a pair of entry (hash, offset).
+      // Seek until the end of the bucket.
+      u4* entry_max = _entries + BUCKET_OFFSET(_buckets[index + 1]);
+      while (entry < entry_max) {
+        unsigned int h = (unsigned int)(entry[0]);
+        if (h == hash) {
+          T res = decode_entry(this, entry[1], name, len);
+          if (res != NULL) {
+            return res;
+          }
+        }
+        entry += 2;
+      }
+    }
+  }
+  return NULL;
+}
+
+#endif // SHARE_VM_CLASSFILE_COMPACTHASHTABLE_INLINE_HPP