1 /*
   2  * Copyright (c) 2013, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 
  25 package org.graalvm.compiler.replacements.amd64;
  26 
  27 import org.graalvm.compiler.api.replacements.ClassSubstitution;
  28 import org.graalvm.compiler.api.replacements.Fold;
  29 import org.graalvm.compiler.api.replacements.Fold.InjectedParameter;
  30 import org.graalvm.compiler.api.replacements.MethodSubstitution;
  31 import org.graalvm.compiler.core.common.SuppressFBWarnings;
  32 import org.graalvm.compiler.graph.Node.ConstantNodeParameter;
  33 import org.graalvm.compiler.replacements.StringSubstitutions;
  34 import org.graalvm.compiler.replacements.nodes.ArrayCompareToNode;
  35 import org.graalvm.compiler.replacements.nodes.ArrayRegionEqualsNode;
  36 import org.graalvm.compiler.word.Word;
  37 import jdk.internal.vm.compiler.word.Pointer;
  38 
  39 import jdk.vm.ci.meta.JavaKind;
  40 import jdk.vm.ci.meta.MetaAccessProvider;
  41 
  42 // JaCoCo Exclude
  43 
  44 /**
  45  * Substitutions for {@link java.lang.String} methods.
  46  */
  47 @ClassSubstitution(String.class)
  48 public class AMD64StringSubstitutions {
  49 
  50     @Fold
  51     static int charArrayBaseOffset(@InjectedParameter MetaAccessProvider metaAccess) {
  52         return metaAccess.getArrayBaseOffset(JavaKind.Char);
  53     }
  54 
  55     @Fold
  56     static int charArrayIndexScale(@InjectedParameter MetaAccessProvider metaAccess) {
  57         return metaAccess.getArrayIndexScale(JavaKind.Char);
  58     }
  59 
  60     /** Marker value for the {@link InjectedParameter} injected parameter. */
  61     static final MetaAccessProvider INJECTED = null;
  62 
  63     // Only exists in JDK <= 8
  64     @MethodSubstitution(isStatic = true, optional = true)
  65     public static int indexOf(char[] source, int sourceOffset, int sourceCount,
  66                     @ConstantNodeParameter char[] target, int targetOffset, int targetCount,
  67                     int origFromIndex) {
  68         int fromIndex = origFromIndex;
  69         if (fromIndex >= sourceCount) {
  70             return (targetCount == 0 ? sourceCount : -1);
  71         }
  72         if (fromIndex < 0) {
  73             fromIndex = 0;
  74         }
  75         if (targetCount == 0) {
  76             // The empty string is in every string.
  77             return fromIndex;
  78         }
  79 
  80         int totalOffset = sourceOffset + fromIndex;
  81         if (sourceCount - fromIndex < targetCount) {
  82             // The empty string contains nothing except the empty string.
  83             return -1;
  84         }
  85 
  86         if (targetCount == 1) {
  87             Pointer sourcePointer = Word.objectToTrackedPointer(source).add(charArrayBaseOffset(INJECTED)).add(totalOffset * charArrayIndexScale(INJECTED));
  88             int indexOfResult = AMD64ArrayIndexOf.indexOf1Char(sourcePointer, sourceCount - fromIndex, target[targetOffset]);
  89             if (indexOfResult >= 0) {
  90                 return indexOfResult + totalOffset;
  91             }
  92             return indexOfResult;
  93         } else if (targetCount == 2) {
  94             Pointer sourcePointer = Word.objectToTrackedPointer(source).add(charArrayBaseOffset(INJECTED)).add(totalOffset * charArrayIndexScale(INJECTED));
  95             int indexOfResult = AMD64ArrayIndexOf.indexOfTwoConsecutiveChars(sourcePointer, sourceCount - fromIndex, target[targetOffset], target[targetOffset + 1]);
  96             if (indexOfResult >= 0) {
  97                 return indexOfResult + totalOffset;
  98             }
  99             return indexOfResult;
 100         } else {
 101             int haystackLength = sourceCount - (fromIndex + (targetCount - 2));
 102             while (haystackLength > 0) {
 103                 Pointer sourcePointer = Word.objectToTrackedPointer(source).add(charArrayBaseOffset(INJECTED)).add(totalOffset * charArrayIndexScale(INJECTED));
 104                 int indexOfResult = AMD64ArrayIndexOf.indexOfTwoConsecutiveChars(sourcePointer, haystackLength, target[targetOffset], target[targetOffset + 1]);
 105                 if (indexOfResult < 0) {
 106                     return -1;
 107                 }
 108                 totalOffset += indexOfResult;
 109                 haystackLength -= (indexOfResult + 1);
 110                 Pointer cmpSourcePointer = Word.objectToTrackedPointer(source).add(charArrayBaseOffset(INJECTED)).add(totalOffset * charArrayIndexScale(INJECTED));
 111                 Pointer targetPointer = Word.objectToTrackedPointer(target).add(charArrayBaseOffset(INJECTED)).add(targetOffset * charArrayIndexScale(INJECTED));
 112                 if (ArrayRegionEqualsNode.regionEquals(cmpSourcePointer, targetPointer, targetCount, JavaKind.Char)) {
 113                     return totalOffset;
 114                 }
 115                 totalOffset++;
 116             }
 117             return -1;
 118         }
 119     }
 120 
 121     // Only exists in JDK <= 8
 122     @MethodSubstitution(isStatic = false, optional = true)
 123     public static int indexOf(String source, int ch, int origFromIndex) {
 124         int fromIndex = origFromIndex;
 125         final int sourceCount = source.length();
 126         if (fromIndex >= sourceCount) {
 127             // Note: fromIndex might be near -1>>>1.
 128             return -1;
 129         }
 130         if (fromIndex < 0) {
 131             fromIndex = 0;
 132         }
 133 
 134         if (ch < Character.MIN_SUPPLEMENTARY_CODE_POINT) {
 135             char[] sourceArray = StringSubstitutions.getValue(source);
 136 
 137             Pointer sourcePointer = Word.objectToTrackedPointer(sourceArray).add(charArrayBaseOffset(INJECTED)).add(fromIndex * charArrayIndexScale(INJECTED));
 138             int result = AMD64ArrayIndexOf.indexOf1Char(sourcePointer, sourceCount - fromIndex, (char) ch);
 139             if (result != -1) {
 140                 return result + fromIndex;
 141             }
 142             return result;
 143         } else {
 144             return indexOf(source, ch, origFromIndex);
 145         }
 146     }
 147 
 148     @MethodSubstitution(isStatic = false)
 149     @SuppressFBWarnings(value = "ES_COMPARING_PARAMETER_STRING_WITH_EQ", justification = "reference equality on the receiver is what we want")
 150     public static int compareTo(String receiver, String anotherString) {
 151         if (receiver == anotherString) {
 152             return 0;
 153         }
 154         char[] value = StringSubstitutions.getValue(receiver);
 155         char[] other = StringSubstitutions.getValue(anotherString);
 156         return ArrayCompareToNode.compareTo(value, other, value.length << 1, other.length << 1, JavaKind.Char, JavaKind.Char);
 157     }
 158 
 159 }