Mercurial > hg > truffle
view graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/snippets/ObjectSnippets.java @ 7273:7f6bf286629c
replace checked casts with unsafe casts in snippets where the exact type of a value loaded from metadata is known
author | Doug Simon <doug.simon@oracle.com> |
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date | Tue, 18 Dec 2012 17:59:03 +0100 |
parents | 855b2c53543f |
children | 4f220c85044d |
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/* * Copyright (c) 2012, 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. */ package com.oracle.graal.hotspot.snippets; import static com.oracle.graal.hotspot.snippets.HotSpotSnippetUtils.*; import static com.oracle.graal.nodes.extended.UnsafeCastNode.*; import com.oracle.graal.hotspot.nodes.*; import com.oracle.graal.snippets.*; import com.oracle.graal.snippets.ClassSubstitution.MethodSubstitution; /** * Snippets for {@link java.lang.Object} methods. */ @ClassSubstitution(java.lang.Object.class) public class ObjectSnippets implements SnippetsInterface { @MethodSubstitution(isStatic = false) public static Class<?> getClass(final Object thisObj) { Word hub = loadHub(thisObj); return unsafeCast(readFinalObject(hub, classMirrorOffset()), Class.class, true, true); } @MethodSubstitution(isStatic = false) public static int hashCode(final Object thisObj) { Word mark = loadWordFromObject(thisObj, markOffset()); // this code is independent from biased locking (although it does not look that way) final Word biasedLock = mark.and(biasedLockMaskInPlace()); if (biasedLock.toLong() == unlockedMask()) { int hash = (int) (mark.toLong() >>> identityHashCodeShift()); if (hash != uninitializedIdentityHashCodeValue()) { return hash; } } return IdentityHashCodeStubCall.call(thisObj); } }