001/* 002 * Copyright (c) 2013, 2014, Oracle and/or its affiliates. All rights reserved. 003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 004 * 005 * This code is free software; you can redistribute it and/or modify it 006 * under the terms of the GNU General Public License version 2 only, as 007 * published by the Free Software Foundation. 008 * 009 * This code is distributed in the hope that it will be useful, but WITHOUT 010 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 011 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 012 * version 2 for more details (a copy is included in the LICENSE file that 013 * accompanied this code). 014 * 015 * You should have received a copy of the GNU General Public License version 016 * 2 along with this work; if not, write to the Free Software Foundation, 017 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 018 * 019 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 020 * or visit www.oracle.com if you need additional information or have any 021 * questions. 022 */ 023package com.oracle.graal.hotspot.replacements; 024 025import static com.oracle.graal.compiler.common.GraalOptions.*; 026import static com.oracle.graal.hotspot.replacements.HotSpotReplacementsUtil.*; 027import static com.oracle.graal.nodes.extended.BranchProbabilityNode.*; 028 029import java.util.*; 030 031import jdk.internal.jvmci.hotspot.*; 032import jdk.internal.jvmci.meta.*; 033 034import com.oracle.graal.hotspot.word.*; 035import com.oracle.graal.nodes.*; 036import com.oracle.graal.nodes.spi.*; 037import com.oracle.graal.replacements.*; 038import com.oracle.graal.word.*; 039 040//JaCoCo Exclude 041 042/** 043 * Utilities and common code paths used by the type check snippets. 044 */ 045public class TypeCheckSnippetUtils { 046 047 static boolean checkSecondarySubType(KlassPointer t, KlassPointer s) { 048 // if (S.cache == T) return true 049 if (s.readKlassPointer(secondarySuperCacheOffset(), SECONDARY_SUPER_CACHE_LOCATION).equal(t)) { 050 cacheHit.inc(); 051 return true; 052 } 053 054 return checkSelfAndSupers(t, s); 055 } 056 057 static boolean checkUnknownSubType(KlassPointer t, KlassPointer s) { 058 // int off = T.offset 059 int superCheckOffset = t.readInt(superCheckOffsetOffset(), KLASS_SUPER_CHECK_OFFSET_LOCATION); 060 boolean primary = superCheckOffset != secondarySuperCacheOffset(); 061 062 // if (T = S[off]) return true 063 if (s.readKlassPointer(superCheckOffset, PRIMARY_SUPERS_LOCATION).equal(t)) { 064 if (primary) { 065 cacheHit.inc(); 066 } else { 067 displayHit.inc(); 068 } 069 return true; 070 } 071 072 // if (off != &cache) return false 073 if (primary) { 074 displayMiss.inc(); 075 return false; 076 } 077 078 return checkSelfAndSupers(t, s); 079 } 080 081 private static boolean checkSelfAndSupers(KlassPointer t, KlassPointer s) { 082 // if (T == S) return true 083 if (s.equal(t)) { 084 T_equals_S.inc(); 085 return true; 086 } 087 088 // if (S.scan_s_s_array(T)) { S.cache = T; return true; } 089 Word secondarySupers = s.readWord(secondarySupersOffset(), SECONDARY_SUPERS_LOCATION); 090 int length = secondarySupers.readInt(metaspaceArrayLengthOffset(), METASPACE_ARRAY_LENGTH_LOCATION); 091 for (int i = 0; i < length; i++) { 092 if (probability(NOT_LIKELY_PROBABILITY, t.equal(loadSecondarySupersElement(secondarySupers, i)))) { 093 s.writeKlassPointer(secondarySuperCacheOffset(), t, SECONDARY_SUPER_CACHE_LOCATION); 094 secondariesHit.inc(); 095 return true; 096 } 097 } 098 secondariesMiss.inc(); 099 return false; 100 } 101 102 /** 103 * A set of type check hints ordered by decreasing probabilities. 104 */ 105 public static class Hints { 106 107 /** 108 * The hubs of the hint types. 109 */ 110 public final ConstantNode[] hubs; 111 112 /** 113 * A predicate over {@link #hubs} specifying whether the corresponding hint type is a 114 * sub-type of the checked type. 115 */ 116 public final boolean[] isPositive; 117 118 Hints(ConstantNode[] hints, boolean[] hintIsPositive) { 119 this.hubs = hints; 120 this.isPositive = hintIsPositive; 121 } 122 } 123 124 static Hints createHints(TypeCheckHints hints, MetaAccessProvider metaAccess, boolean positiveOnly, StructuredGraph graph, LoweringTool tool) { 125 ConstantNode[] hubs = new ConstantNode[hints.hints.length]; 126 boolean[] isPositive = new boolean[hints.hints.length]; 127 int index = 0; 128 for (int i = 0; i < hubs.length; i++) { 129 if (!positiveOnly || hints.hints[i].positive) { 130 hubs[index] = ConstantNode.forConstant(tool.getStampProvider().createHubStamp(true), ((HotSpotResolvedObjectType) hints.hints[i].type).klass(), metaAccess, graph); 131 isPositive[index] = hints.hints[i].positive; 132 index++; 133 } 134 } 135 if (positiveOnly && index != hubs.length) { 136 assert index < hubs.length; 137 hubs = Arrays.copyOf(hubs, index); 138 isPositive = Arrays.copyOf(isPositive, index); 139 } 140 return new Hints(hubs, isPositive); 141 } 142 143 static KlassPointer loadSecondarySupersElement(Word metaspaceArray, int index) { 144 return KlassPointer.fromWord(metaspaceArray.readWord(metaspaceArrayBaseOffset() + index * wordSize(), SECONDARY_SUPERS_ELEMENT_LOCATION)); 145 } 146 147 private static final SnippetCounter.Group counters = SnippetCounters.getValue() ? new SnippetCounter.Group("TypeCheck") : null; 148 static final SnippetCounter hintsHit = new SnippetCounter(counters, "hintsHit", "hit a hint type"); 149 static final SnippetCounter hintsMiss = new SnippetCounter(counters, "hintsMiss", "missed a hint type"); 150 static final SnippetCounter exactHit = new SnippetCounter(counters, "exactHit", "exact type test succeeded"); 151 static final SnippetCounter exactMiss = new SnippetCounter(counters, "exactMiss", "exact type test failed"); 152 static final SnippetCounter isNull = new SnippetCounter(counters, "isNull", "object tested was null"); 153 static final SnippetCounter cacheHit = new SnippetCounter(counters, "cacheHit", "secondary type cache hit"); 154 static final SnippetCounter secondariesHit = new SnippetCounter(counters, "secondariesHit", "secondaries scan succeeded"); 155 static final SnippetCounter secondariesMiss = new SnippetCounter(counters, "secondariesMiss", "secondaries scan failed"); 156 static final SnippetCounter displayHit = new SnippetCounter(counters, "displayHit", "primary type test succeeded"); 157 static final SnippetCounter displayMiss = new SnippetCounter(counters, "displayMiss", "primary type test failed"); 158 static final SnippetCounter T_equals_S = new SnippetCounter(counters, "T_equals_S", "object type was equal to secondary type"); 159 160}