1 /* 2 * Copyright (c) 2016, 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.hotspot.replacements; 26 27 import java.io.ByteArrayOutputStream; 28 import java.io.DataOutputStream; 29 import java.nio.ByteBuffer; 30 31 import org.graalvm.compiler.core.common.PermanentBailoutException; 32 import org.graalvm.compiler.core.common.type.DataPointerConstant; 33 34 import jdk.vm.ci.hotspot.HotSpotMetaspaceConstant; 35 import jdk.vm.ci.hotspot.HotSpotObjectConstant; 36 import jdk.vm.ci.hotspot.HotSpotResolvedJavaMethod; 37 import jdk.vm.ci.hotspot.HotSpotResolvedObjectType; 38 import jdk.vm.ci.meta.Constant; 39 40 /** 41 * Represents an encoded representation of a constant. 42 */ 43 public final class EncodedSymbolConstant extends DataPointerConstant { 44 private final Constant constant; 45 private byte[] bytes; 46 EncodedSymbolConstant(Constant constant)47 public EncodedSymbolConstant(Constant constant) { 48 super(1); 49 this.constant = constant; 50 } 51 52 @Override getSerializedSize()53 public int getSerializedSize() { 54 return getEncodedConstant().length; 55 } 56 57 @Override serialize(ByteBuffer buffer)58 public void serialize(ByteBuffer buffer) { 59 buffer.put(getEncodedConstant()); 60 } 61 62 /** 63 * Converts a string to a byte array with modified UTF-8 encoding. The first two bytes of the 64 * byte array store the length of the string in bytes. 65 * 66 * @param s a java.lang.String in UTF-16 67 */ toUTF8String(String s)68 private static byte[] toUTF8String(String s) { 69 try (ByteArrayOutputStream bytes = new ByteArrayOutputStream()) { 70 DataOutputStream stream = new DataOutputStream(bytes); 71 stream.writeUTF(s); 72 return bytes.toByteArray(); 73 } catch (Exception e) { 74 throw new PermanentBailoutException(e, "String conversion failed: %s", s); 75 } 76 } 77 encodeConstant(Constant constant)78 private static byte[] encodeConstant(Constant constant) { 79 assert constant != null; 80 if (constant instanceof HotSpotObjectConstant) { 81 return toUTF8String(((HotSpotObjectConstant) constant).asObject(String.class)); 82 } else if (constant instanceof HotSpotMetaspaceConstant) { 83 HotSpotMetaspaceConstant metaspaceConstant = ((HotSpotMetaspaceConstant) constant); 84 HotSpotResolvedObjectType klass = metaspaceConstant.asResolvedJavaType(); 85 if (klass != null) { 86 return toUTF8String(klass.getName()); 87 } 88 HotSpotResolvedJavaMethod method = metaspaceConstant.asResolvedJavaMethod(); 89 if (method != null) { 90 byte[] methodName = toUTF8String(method.getName()); 91 byte[] signature = toUTF8String(method.getSignature().toMethodDescriptor()); 92 byte[] result = new byte[methodName.length + signature.length]; 93 int resultPos = 0; 94 System.arraycopy(methodName, 0, result, resultPos, methodName.length); 95 resultPos += methodName.length; 96 System.arraycopy(signature, 0, result, resultPos, signature.length); 97 resultPos += signature.length; 98 assert resultPos == result.length; 99 return result; 100 } 101 102 } 103 throw new PermanentBailoutException("Encoding of constant %s failed", constant); 104 } 105 getEncodedConstant()106 public byte[] getEncodedConstant() { 107 if (bytes == null) { 108 bytes = encodeConstant(constant); 109 } 110 return bytes; 111 } 112 113 @Override toValueString()114 public String toValueString() { 115 return "encoded symbol\"" + constant.toValueString() + "\""; 116 } 117 118 } 119