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. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 package valhalla.shady; 26 27 import jdk.experimental.bytecode.BasicClassBuilder; 28 import jdk.internal.misc.Unsafe; 29 import jdk.internal.misc.VM; 30 import sun.security.action.GetPropertyAction; 31 32 import java.lang.annotation.Annotation; 33 import java.io.BufferedOutputStream; 34 import java.io.File; 35 import java.io.IOException; 36 import java.io.OutputStream; 37 import java.nio.file.Files; 38 import java.nio.file.Path; 39 import java.nio.file.Paths; 40 import java.security.ProtectionDomain; 41 import java.util.Properties; 42 import java.util.concurrent.ConcurrentHashMap; 43 44 import static jdk.internal.org.objectweb.asm.Opcodes.*; 45 46 import jdk.internal.misc.JavaLangAccess; 47 import jdk.internal.misc.SharedSecrets; 48 public class MinimalValueTypes_1_0 { 49 50 public static final int V53_1 = 1 << 16 | 53; 51 public static final int ACC_VALUE = ACC_NATIVE; 52 public static final String OBJECT_CLASS_DESC = "java/lang/Object"; 53 public static final String VALUE_CLASS_DESC = "java/lang/__Value"; 54 55 public static final String DERIVE_VALUE_TYPE_DESC = "Ljdk/incubator/mvt/ValueCapableClass;"; 56 public static final String DERIVE_VT_CLASSNAME_POSTFIX = "$Value"; 57 public static final int DERIVE_VT_CLASS_ACCESS = ACC_PUBLIC|ACC_SUPER|ACC_FINAL|ACC_VALUE|ACC_SYNTHETIC; 58 59 public static final boolean DUMP_CLASS_FILES; 60 private static final boolean VALUE_TYPE_ENABLED; 61 private static final JavaLangAccess JLA; 62 63 static { 64 // Use same property as in j.l.invoke.MethodHandleStatics 65 Properties props = GetPropertyAction.privilegedGetProperties(); 66 DUMP_CLASS_FILES = Boolean.parseBoolean( 67 props.getProperty("java.lang.invoke.MethodHandle.DUMP_CLASS_FILES")); 68 69 VALUE_TYPE_ENABLED = Boolean.parseBoolean( 70 props.getProperty("valhalla.enableValueType")); 71 72 JLA = SharedSecrets.getJavaLangAccess(); 73 } 74 75 private static final ConcurrentHashMap<Class<?>, ValueTypeHolder<?>> BOX_TO_VT 76 = new ConcurrentHashMap<>(); 77 78 /** 79 * Returns the {@code ValueTypeHolder} representing the value type 80 * for the given value capable type. 81 * 82 * @throws UnsupportedOperationException if MVT is not enabled 83 * @throws IllegalArgumentException if the given class is not value capable class 84 */ 85 @SuppressWarnings("unchecked") 86 public static <T> ValueTypeHolder<T> getValueFor(Class<T> vcc) { 87 if (!MinimalValueTypes_1_0.isValueTypeEnabled()) { 88 throw new UnsupportedOperationException("MVT is not enabled"); 89 } 90 91 if (!MinimalValueTypes_1_0.isValueCapable(vcc)) { 92 throw new IllegalArgumentException("Class " + vcc + " not a value capable class"); 93 } 94 95 ValueTypeHolder<T> vt = (ValueTypeHolder<T>) BOX_TO_VT.get(vcc); 96 if (vt != null) { 97 return vt; 98 } 99 100 Class<T> valueClass = (Class<T>) MinimalValueTypes_1_0.getValueTypeClass(vcc); 101 vt = new ValueTypeHolder<T>(vcc, valueClass); 102 ValueTypeHolder<T> old = (ValueTypeHolder<T>) BOX_TO_VT.putIfAbsent(vcc, vt); 103 if (old != null) { 104 vt = old; 105 } 106 return vt; 107 } 108 109 /** 110 * Returns the {@code ValueTypeHolder} representing the value type 111 * for the given class is a derived value type; otherwise {@code null}. 112 */ 113 @SuppressWarnings("unchecked") 114 public static <T> ValueTypeHolder<T> findValueType(Class<T> c) { 115 if (MinimalValueTypes_1_0.isValueType(c)) { 116 return (ValueTypeHolder<T>) getValueFor(MinimalValueTypes_1_0.getValueCapableClass(c)); 117 } else { 118 return null; 119 } 120 } 121 122 /** 123 * Returns true if MVT is enabled. 124 * 125 * jdk.incubator.mvt must be resolved in the boot layer. 126 */ 127 public static boolean isValueTypeEnabled() { 128 return VALUE_TYPE_ENABLED; 129 } 130 131 public static boolean isValueType(Class<?> dvt) { 132 return (dvt.getModifiers() & ACC_VALUE) != 0; 133 } 134 135 /** 136 * Returns true if the given class is a value-capable class, i.e. 137 * annotated with @ValueCapableClass. 138 */ 139 public static boolean isValueCapable(Class<?> vcc) { 140 if (!isValueTypeEnabled()) { 141 return false; 142 } 143 144 return ValueClassHelper.hasValueCapableAnnotation(vcc); 145 } 146 147 public static Class<?> getValueCapableClass(Class<?> dvt) { 148 if (!isValueType(dvt)) { 149 throw new IllegalArgumentException(dvt + " is not a derived value type"); 150 } 151 152 Class<?> c = Class.forName(dvt.getModule(), getValueCapableClassName(dvt.getName())); 153 if (c == null || !isValueCapable(c)) { 154 throw new InternalError(dvt + " not bound to ValueType"); 155 } 156 return c; 157 } 158 159 public static Class<?> getValueTypeClass(Class<?> vcc) { 160 if (!isValueCapable(vcc)) { 161 throw new IllegalArgumentException(vcc + " is not a value capable class"); 162 } 163 return loadValueTypeClass(vcc, getValueTypeClassName(vcc.getName())); 164 } 165 166 public static Class<?> loadValueTypeClass(Class<?> vcc, String className) { 167 if (!isValueCapable(vcc)) { 168 throw new IllegalArgumentException(vcc.getName() + " is not a value capable class"); 169 } 170 return JLA.loadValueTypeClass(vcc.getModule(), vcc.getClassLoader(), className); 171 } 172 173 /** 174 * This method is invoked by the VM. 175 * 176 * @param fds : name/sig pairs 177 * @param fmods : field modifiers 178 */ 179 public static String createDerivedValueType(String vccInternalClassName, 180 ClassLoader cl, 181 ProtectionDomain pd, 182 String[] fds, 183 int[] fmods) { 184 String vtInternalClassName = getValueTypeClassName(vccInternalClassName); 185 ValueTypeDesc valueTypeDesc = new ValueTypeDesc(vccInternalClassName, fds, fmods); 186 byte[] valueTypeBytes = createValueType(valueTypeDesc); 187 Class<?> vtClass = Unsafe.getUnsafe().defineClass(vtInternalClassName, valueTypeBytes, 0, valueTypeBytes.length, cl, pd); 188 return vtInternalClassName; 189 } 190 191 public static byte[] createValueType(ValueTypeDesc valueTypeDesc) { 192 193 String valueTypeClassName = getValueTypeClassName(valueTypeDesc); 194 195 BasicClassBuilder builder = new BasicClassBuilder(mangleValueClassName(valueTypeClassName), 53, 1) 196 .withFlags(DERIVE_VT_CLASS_ACCESS) 197 .withSuperclass(mangleValueClassName(VALUE_CLASS_DESC)); 198 199 ValueTypeDesc.Field[] fields = valueTypeDesc.getFields(); 200 for (ValueTypeDesc.Field field : fields) { 201 builder.withField(field.name, field.type, F -> F.withFlags(field.modifiers)); 202 } 203 204 byte[] newBytes = builder.build(); 205 maybeDump(valueTypeClassName, newBytes); 206 return newBytes; 207 } 208 209 /** debugging flag for saving generated class files */ 210 private static final Path DUMP_CLASS_FILES_DIR; 211 212 static { 213 if (DUMP_CLASS_FILES) { 214 try { 215 Path dumpDir = Paths.get("DUMP_CLASS_FILES"); 216 Files.createDirectories(dumpDir); 217 DUMP_CLASS_FILES_DIR = dumpDir; 218 } catch (Exception e) { 219 throw new InternalError(e); 220 } 221 } else { 222 DUMP_CLASS_FILES_DIR = null; 223 } 224 } 225 226 public static void maybeDump(final String className, final byte[] classFile) { 227 if (DUMP_CLASS_FILES_DIR != null) { 228 java.security.AccessController.doPrivileged( 229 new java.security.PrivilegedAction<>() { 230 public Void run() { 231 String dumpName = className; 232 //dumpName = dumpName.replace('/', '-'); 233 Path dumpFile = DUMP_CLASS_FILES_DIR.resolve(dumpName + ".class"); 234 File root = dumpFile.getParent().toFile(); 235 if (!root.exists() && !root.mkdirs()) { 236 throw new IllegalStateException("Could not create dump file directory: " + root); 237 } 238 System.out.println("dump: " + dumpFile); 239 try (OutputStream os = Files.newOutputStream(dumpFile); 240 BufferedOutputStream bos = new BufferedOutputStream(os)) { 241 bos.write(classFile); 242 } catch (IOException ex) { 243 throw new InternalError(ex); 244 } 245 return null; 246 } 247 }); 248 249 } 250 } 251 252 private final native Class<?> getDerivedValueType(Class<?> ofClass); 253 254 public static Class<?> getValueClass() { 255 return isValueTypeEnabled() ? ValueClassHelper.VALUE_CLASS : null; 256 } 257 258 public static String getValueTypeClassName(ValueTypeDesc valueTypeDesc) { 259 return getValueTypeClassName(valueTypeDesc.getName()); 260 } 261 262 public static String getValueTypeClassName(String vccName) { 263 return vccName + DERIVE_VT_CLASSNAME_POSTFIX; 264 } 265 266 public static String getValueCapableClassName(String valName) { 267 return valName.substring(0, valName.length() - DERIVE_VT_CLASSNAME_POSTFIX.length()); 268 } 269 270 public static String mangleValueClassName(String name) { 271 return ";Q" + name + ";"; 272 } 273 274 /* 275 * This helper class should only be loaded when MVT is enabled. 276 * Otherwise, it will load __Value but if MVT is not enabled and 277 * that would fail verification. 278 */ 279 private static class ValueClassHelper { 280 static final Class<?> VALUE_CLASS = 281 (Class<?>)(Object)__Value.class; //hack around static type-system checks 282 283 static volatile Class<? extends Annotation> annotationClass; 284 static volatile Class<?> valueTypeClass; 285 286 static boolean hasValueCapableAnnotation(Class<?> c) { 287 if (!VM.isModuleSystemInited()) { 288 return false; 289 } 290 Class<? extends Annotation> annClass = annotationClass; 291 if (annClass == null) { 292 annotationClass = annClass = loadValueCapableAnnotation(); 293 } 294 return annClass != null && 295 c.getDeclaredAnnotation(annClass) != null; 296 } 297 298 static Class<? extends Annotation> loadValueCapableAnnotation() { 299 try { 300 @SuppressWarnings("unchecked") 301 Class<? extends Annotation> c = (Class<? extends Annotation>) 302 Class.forName("jdk.incubator.mvt.ValueCapableClass", false, 303 ClassLoader.getPlatformClassLoader()); 304 return c; 305 306 } catch (ClassNotFoundException e) { 307 return null; 308 } 309 } 310 311 static Class<?> incubatorValueTypeClass() { 312 Class<?> c = valueTypeClass; 313 if (c == null) { 314 try { 315 valueTypeClass = c = 316 Class.forName("jdk.incubator.mvt.ValueType", false, 317 ClassLoader.getPlatformClassLoader()); 318 } catch (ClassNotFoundException e) { 319 } 320 } 321 return valueTypeClass; 322 } 323 } 324 325 static Class<?> getIncubatorValueTypeClass() { 326 if (!isValueTypeEnabled()) { 327 throw new UnsupportedOperationException("MVT is not enabled"); 328 } 329 return ValueClassHelper.incubatorValueTypeClass(); 330 } 331 }