1 /* 2 * Copyright (c) 2008, 2025, 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 26 package java.lang.invoke; 27 28 import jdk.internal.access.JavaLangInvokeAccess; 29 import jdk.internal.access.SharedSecrets; 30 import jdk.internal.constant.ClassOrInterfaceDescImpl; 31 import jdk.internal.constant.ConstantUtils; 32 import jdk.internal.constant.MethodTypeDescImpl; 33 import jdk.internal.foreign.abi.NativeEntryPoint; 34 import jdk.internal.reflect.CallerSensitive; 35 import jdk.internal.reflect.Reflection; 36 import jdk.internal.vm.annotation.AOTRuntimeSetup; 37 import jdk.internal.vm.annotation.AOTSafeClassInitializer; 38 import jdk.internal.vm.annotation.ForceInline; 39 import jdk.internal.vm.annotation.Hidden; 40 import jdk.internal.vm.annotation.Stable; 41 import sun.invoke.util.ValueConversions; 42 import sun.invoke.util.VerifyType; 43 import sun.invoke.util.Wrapper; 44 45 import java.lang.classfile.ClassFile; 46 import java.lang.constant.ClassDesc; 47 import java.lang.foreign.MemoryLayout; 48 import java.lang.invoke.MethodHandles.Lookup; 49 import java.lang.reflect.Array; 50 import java.lang.reflect.Constructor; 51 import java.lang.reflect.Field; 52 import java.nio.ByteOrder; 53 import java.util.Arrays; 54 import java.util.Collections; 55 import java.util.HashMap; 56 import java.util.Iterator; 57 import java.util.List; 58 import java.util.Map; 59 import java.util.Objects; 60 import java.util.concurrent.ConcurrentHashMap; 61 import java.util.function.Function; 62 import java.util.stream.Stream; 63 64 import static java.lang.classfile.ClassFile.*; 65 import static java.lang.constant.ConstantDescs.*; 66 import static java.lang.invoke.LambdaForm.*; 67 import static java.lang.invoke.MethodHandleNatives.Constants.MN_CALLER_SENSITIVE; 68 import static java.lang.invoke.MethodHandleNatives.Constants.MN_HIDDEN_MEMBER; 69 import static java.lang.invoke.MethodHandleNatives.Constants.NESTMATE_CLASS; 70 import static java.lang.invoke.MethodHandleStatics.*; 71 import static java.lang.invoke.MethodHandles.Lookup.IMPL_LOOKUP; 72 73 /** 74 * Trusted implementation code for MethodHandle. 75 * @author jrose 76 */ 77 @AOTSafeClassInitializer 78 /*non-public*/ 79 abstract class MethodHandleImpl { 80 81 /// Factory methods to create method handles: 82 83 static MethodHandle makeArrayElementAccessor(Class<?> arrayClass, ArrayAccess access) { 84 if (arrayClass == Object[].class) { 85 return ArrayAccess.objectAccessor(access); 86 } 87 if (!arrayClass.isArray()) 88 throw newIllegalArgumentException("not an array: "+arrayClass); 89 MethodHandle[] cache = ArrayAccessor.TYPED_ACCESSORS.get(arrayClass); 90 int cacheIndex = ArrayAccess.cacheIndex(access); 91 MethodHandle mh = cache[cacheIndex]; 92 if (mh != null) return mh; 93 mh = ArrayAccessor.getAccessor(arrayClass, access); 94 MethodType correctType = ArrayAccessor.correctType(arrayClass, access); 95 if (mh.type() != correctType) { 96 assert(mh.type().parameterType(0) == Object[].class); 97 /* if access == SET */ assert(access != ArrayAccess.SET || mh.type().parameterType(2) == Object.class); 98 /* if access == GET */ assert(access != ArrayAccess.GET || 99 (mh.type().returnType() == Object.class && 100 correctType.parameterType(0).getComponentType() == correctType.returnType())); 101 // safe to view non-strictly, because element type follows from array type 102 mh = mh.viewAsType(correctType, false); 103 } 104 mh = makeIntrinsic(mh, ArrayAccess.intrinsic(access)); 105 // Atomically update accessor cache. 106 synchronized(cache) { 107 if (cache[cacheIndex] == null) { 108 cache[cacheIndex] = mh; 109 } else { 110 // Throw away newly constructed accessor and use cached version. 111 mh = cache[cacheIndex]; 112 } 113 } 114 return mh; 115 } 116 117 enum ArrayAccess { 118 GET, SET, LENGTH; 119 120 // As ArrayAccess and ArrayAccessor have a circular dependency, the ArrayAccess properties cannot be stored in 121 // final fields. 122 123 static String opName(ArrayAccess a) { 124 return switch (a) { 125 case GET -> "getElement"; 126 case SET -> "setElement"; 127 case LENGTH -> "length"; 128 default -> throw unmatchedArrayAccess(a); 129 }; 130 } 131 132 static MethodHandle objectAccessor(ArrayAccess a) { 133 return switch (a) { 134 case GET -> ArrayAccessor.OBJECT_ARRAY_GETTER; 135 case SET -> ArrayAccessor.OBJECT_ARRAY_SETTER; 136 case LENGTH -> ArrayAccessor.OBJECT_ARRAY_LENGTH; 137 default -> throw unmatchedArrayAccess(a); 138 }; 139 } 140 141 static int cacheIndex(ArrayAccess a) { 142 return switch (a) { 143 case GET -> ArrayAccessor.GETTER_INDEX; 144 case SET -> ArrayAccessor.SETTER_INDEX; 145 case LENGTH -> ArrayAccessor.LENGTH_INDEX; 146 default -> throw unmatchedArrayAccess(a); 147 }; 148 } 149 150 static Intrinsic intrinsic(ArrayAccess a) { 151 return switch (a) { 152 case GET -> Intrinsic.ARRAY_LOAD; 153 case SET -> Intrinsic.ARRAY_STORE; 154 case LENGTH -> Intrinsic.ARRAY_LENGTH; 155 default -> throw unmatchedArrayAccess(a); 156 }; 157 } 158 } 159 160 static InternalError unmatchedArrayAccess(ArrayAccess a) { 161 return newInternalError("should not reach here (unmatched ArrayAccess: " + a + ")"); 162 } 163 164 @AOTSafeClassInitializer 165 static final class ArrayAccessor { 166 /// Support for array element and length access 167 static final int GETTER_INDEX = 0, SETTER_INDEX = 1, LENGTH_INDEX = 2, INDEX_LIMIT = 3; 168 static final ClassValue<MethodHandle[]> TYPED_ACCESSORS 169 = new ClassValue<MethodHandle[]>() { 170 @Override 171 protected MethodHandle[] computeValue(Class<?> type) { 172 return new MethodHandle[INDEX_LIMIT]; 173 } 174 }; 175 static final MethodHandle OBJECT_ARRAY_GETTER, OBJECT_ARRAY_SETTER, OBJECT_ARRAY_LENGTH; 176 static { 177 MethodHandle[] cache = TYPED_ACCESSORS.get(Object[].class); 178 cache[GETTER_INDEX] = OBJECT_ARRAY_GETTER = makeIntrinsic(getAccessor(Object[].class, ArrayAccess.GET), Intrinsic.ARRAY_LOAD); 179 cache[SETTER_INDEX] = OBJECT_ARRAY_SETTER = makeIntrinsic(getAccessor(Object[].class, ArrayAccess.SET), Intrinsic.ARRAY_STORE); 180 cache[LENGTH_INDEX] = OBJECT_ARRAY_LENGTH = makeIntrinsic(getAccessor(Object[].class, ArrayAccess.LENGTH), Intrinsic.ARRAY_LENGTH); 181 182 assert(InvokerBytecodeGenerator.isStaticallyInvocable(ArrayAccessor.OBJECT_ARRAY_GETTER.internalMemberName())); 183 assert(InvokerBytecodeGenerator.isStaticallyInvocable(ArrayAccessor.OBJECT_ARRAY_SETTER.internalMemberName())); 184 assert(InvokerBytecodeGenerator.isStaticallyInvocable(ArrayAccessor.OBJECT_ARRAY_LENGTH.internalMemberName())); 185 } 186 187 static int getElementI(int[] a, int i) { return a[i]; } 188 static long getElementJ(long[] a, int i) { return a[i]; } 189 static float getElementF(float[] a, int i) { return a[i]; } 190 static double getElementD(double[] a, int i) { return a[i]; } 191 static boolean getElementZ(boolean[] a, int i) { return a[i]; } 192 static byte getElementB(byte[] a, int i) { return a[i]; } 193 static short getElementS(short[] a, int i) { return a[i]; } 194 static char getElementC(char[] a, int i) { return a[i]; } 195 static Object getElementL(Object[] a, int i) { return a[i]; } 196 197 static void setElementI(int[] a, int i, int x) { a[i] = x; } 198 static void setElementJ(long[] a, int i, long x) { a[i] = x; } 199 static void setElementF(float[] a, int i, float x) { a[i] = x; } 200 static void setElementD(double[] a, int i, double x) { a[i] = x; } 201 static void setElementZ(boolean[] a, int i, boolean x) { a[i] = x; } 202 static void setElementB(byte[] a, int i, byte x) { a[i] = x; } 203 static void setElementS(short[] a, int i, short x) { a[i] = x; } 204 static void setElementC(char[] a, int i, char x) { a[i] = x; } 205 static void setElementL(Object[] a, int i, Object x) { a[i] = x; } 206 207 static int lengthI(int[] a) { return a.length; } 208 static int lengthJ(long[] a) { return a.length; } 209 static int lengthF(float[] a) { return a.length; } 210 static int lengthD(double[] a) { return a.length; } 211 static int lengthZ(boolean[] a) { return a.length; } 212 static int lengthB(byte[] a) { return a.length; } 213 static int lengthS(short[] a) { return a.length; } 214 static int lengthC(char[] a) { return a.length; } 215 static int lengthL(Object[] a) { return a.length; } 216 217 static String name(Class<?> arrayClass, ArrayAccess access) { 218 Class<?> elemClass = arrayClass.getComponentType(); 219 if (elemClass == null) throw newIllegalArgumentException("not an array", arrayClass); 220 return ArrayAccess.opName(access) + Wrapper.basicTypeChar(elemClass); 221 } 222 static MethodType type(Class<?> arrayClass, ArrayAccess access) { 223 Class<?> elemClass = arrayClass.getComponentType(); 224 Class<?> arrayArgClass = arrayClass; 225 if (!elemClass.isPrimitive()) { 226 arrayArgClass = Object[].class; 227 elemClass = Object.class; 228 } 229 return switch (access) { 230 case GET -> MethodType.methodType(elemClass, arrayArgClass, int.class); 231 case SET -> MethodType.methodType(void.class, arrayArgClass, int.class, elemClass); 232 case LENGTH -> MethodType.methodType(int.class, arrayArgClass); 233 default -> throw unmatchedArrayAccess(access); 234 }; 235 } 236 static MethodType correctType(Class<?> arrayClass, ArrayAccess access) { 237 Class<?> elemClass = arrayClass.getComponentType(); 238 return switch (access) { 239 case GET -> MethodType.methodType(elemClass, arrayClass, int.class); 240 case SET -> MethodType.methodType(void.class, arrayClass, int.class, elemClass); 241 case LENGTH -> MethodType.methodType(int.class, arrayClass); 242 default -> throw unmatchedArrayAccess(access); 243 }; 244 } 245 static MethodHandle getAccessor(Class<?> arrayClass, ArrayAccess access) { 246 String name = name(arrayClass, access); 247 MethodType type = type(arrayClass, access); 248 try { 249 return IMPL_LOOKUP.findStatic(ArrayAccessor.class, name, type); 250 } catch (ReflectiveOperationException ex) { 251 throw uncaughtException(ex); 252 } 253 } 254 } 255 256 /** 257 * Create a JVM-level adapter method handle to conform the given method 258 * handle to the similar newType, using only pairwise argument conversions. 259 * For each argument, convert incoming argument to the exact type needed. 260 * The argument conversions allowed are casting, boxing and unboxing, 261 * integral widening or narrowing, and floating point widening or narrowing. 262 * @param srcType required call type 263 * @param target original method handle 264 * @param strict if true, only asType conversions are allowed; if false, explicitCastArguments conversions allowed 265 * @param monobox if true, unboxing conversions are assumed to be exactly typed (Integer to int only, not long or double) 266 * @return an adapter to the original handle with the desired new type, 267 * or the original target if the types are already identical 268 * or null if the adaptation cannot be made 269 */ 270 static MethodHandle makePairwiseConvert(MethodHandle target, MethodType srcType, 271 boolean strict, boolean monobox) { 272 MethodType dstType = target.type(); 273 if (srcType == dstType) 274 return target; 275 return makePairwiseConvertByEditor(target, srcType, strict, monobox); 276 } 277 278 private static int countNonNull(Object[] array) { 279 int count = 0; 280 if (array != null) { 281 for (Object x : array) { 282 if (x != null) ++count; 283 } 284 } 285 return count; 286 } 287 288 static MethodHandle makePairwiseConvertByEditor(MethodHandle target, MethodType srcType, 289 boolean strict, boolean monobox) { 290 // In method types arguments start at index 0, while the LF 291 // editor have the MH receiver at position 0 - adjust appropriately. 292 final int MH_RECEIVER_OFFSET = 1; 293 Object[] convSpecs = computeValueConversions(srcType, target.type(), strict, monobox); 294 int convCount = countNonNull(convSpecs); 295 if (convCount == 0) 296 return target.viewAsType(srcType, strict); 297 MethodType basicSrcType = srcType.basicType(); 298 MethodType midType = target.type().basicType(); 299 BoundMethodHandle mh = target.rebind(); 300 301 // Match each unique conversion to the positions at which it is to be applied 302 HashMap<Object, int[]> convSpecMap = HashMap.newHashMap(convCount); 303 for (int i = 0; i < convSpecs.length - MH_RECEIVER_OFFSET; i++) { 304 Object convSpec = convSpecs[i]; 305 if (convSpec == null) continue; 306 int[] positions = convSpecMap.get(convSpec); 307 if (positions == null) { 308 positions = new int[] { i + MH_RECEIVER_OFFSET }; 309 } else { 310 positions = Arrays.copyOf(positions, positions.length + 1); 311 positions[positions.length - 1] = i + MH_RECEIVER_OFFSET; 312 } 313 convSpecMap.put(convSpec, positions); 314 } 315 for (var entry : convSpecMap.entrySet()) { 316 Object convSpec = entry.getKey(); 317 318 MethodHandle fn; 319 if (convSpec instanceof Class) { 320 fn = getConstantHandle(MH_cast).bindTo(convSpec); 321 } else { 322 fn = (MethodHandle) convSpec; 323 } 324 int[] positions = entry.getValue(); 325 Class<?> newType = basicSrcType.parameterType(positions[0] - MH_RECEIVER_OFFSET); 326 BasicType newBasicType = BasicType.basicType(newType); 327 convCount -= positions.length; 328 if (convCount == 0) { 329 midType = srcType; 330 } else { 331 Class<?>[] ptypes = midType.ptypes().clone(); 332 for (int pos : positions) { 333 ptypes[pos - 1] = newType; 334 } 335 midType = MethodType.methodType(midType.rtype(), ptypes, true); 336 } 337 LambdaForm form2; 338 if (positions.length > 1) { 339 form2 = mh.editor().filterRepeatedArgumentForm(newBasicType, positions); 340 } else { 341 form2 = mh.editor().filterArgumentForm(positions[0], newBasicType); 342 } 343 mh = mh.copyWithExtendL(midType, form2, fn); 344 } 345 Object convSpec = convSpecs[convSpecs.length - 1]; 346 if (convSpec != null) { 347 MethodHandle fn; 348 if (convSpec instanceof Class) { 349 if (convSpec == void.class) 350 fn = null; 351 else 352 fn = getConstantHandle(MH_cast).bindTo(convSpec); 353 } else { 354 fn = (MethodHandle) convSpec; 355 } 356 Class<?> newType = basicSrcType.returnType(); 357 assert(--convCount == 0); 358 midType = srcType; 359 if (fn != null) { 360 mh = mh.rebind(); // rebind if too complex 361 LambdaForm form2 = mh.editor().filterReturnForm(BasicType.basicType(newType), false); 362 mh = mh.copyWithExtendL(midType, form2, fn); 363 } else { 364 LambdaForm form2 = mh.editor().filterReturnForm(BasicType.basicType(newType), true); 365 mh = mh.copyWith(midType, form2); 366 } 367 } 368 assert(convCount == 0); 369 assert(mh.type().equals(srcType)); 370 return mh; 371 } 372 373 static Object[] computeValueConversions(MethodType srcType, MethodType dstType, 374 boolean strict, boolean monobox) { 375 final int INARG_COUNT = srcType.parameterCount(); 376 Object[] convSpecs = null; 377 for (int i = 0; i <= INARG_COUNT; i++) { 378 boolean isRet = (i == INARG_COUNT); 379 Class<?> src = isRet ? dstType.returnType() : srcType.parameterType(i); 380 Class<?> dst = isRet ? srcType.returnType() : dstType.parameterType(i); 381 if (!VerifyType.isNullConversion(src, dst, /*keepInterfaces=*/ strict)) { 382 if (convSpecs == null) { 383 convSpecs = new Object[INARG_COUNT + 1]; 384 } 385 convSpecs[i] = valueConversion(src, dst, strict, monobox); 386 } 387 } 388 return convSpecs; 389 } 390 static MethodHandle makePairwiseConvert(MethodHandle target, MethodType srcType, 391 boolean strict) { 392 return makePairwiseConvert(target, srcType, strict, /*monobox=*/ false); 393 } 394 395 /** 396 * Find a conversion function from the given source to the given destination. 397 * This conversion function will be used as a LF NamedFunction. 398 * Return a Class object if a simple cast is needed. 399 * Return void.class if void is involved. 400 */ 401 static Object valueConversion(Class<?> src, Class<?> dst, boolean strict, boolean monobox) { 402 assert(!VerifyType.isNullConversion(src, dst, /*keepInterfaces=*/ strict)); // caller responsibility 403 if (dst == void.class) 404 return dst; 405 MethodHandle fn; 406 if (src.isPrimitive()) { 407 if (src == void.class) { 408 return void.class; // caller must recognize this specially 409 } else if (dst.isPrimitive()) { 410 // Examples: int->byte, byte->int, boolean->int (!strict) 411 fn = ValueConversions.convertPrimitive(src, dst); 412 } else { 413 // Examples: int->Integer, boolean->Object, float->Number 414 Wrapper wsrc = Wrapper.forPrimitiveType(src); 415 fn = ValueConversions.boxExact(wsrc); 416 assert(fn.type().parameterType(0) == wsrc.primitiveType()); 417 assert(fn.type().returnType() == wsrc.wrapperType()); 418 if (!VerifyType.isNullConversion(wsrc.wrapperType(), dst, strict)) { 419 // Corner case, such as int->Long, which will probably fail. 420 MethodType mt = MethodType.methodType(dst, src); 421 if (strict) 422 fn = fn.asType(mt); 423 else 424 fn = MethodHandleImpl.makePairwiseConvert(fn, mt, /*strict=*/ false); 425 } 426 } 427 } else if (dst.isPrimitive()) { 428 Wrapper wdst = Wrapper.forPrimitiveType(dst); 429 if (monobox || src == wdst.wrapperType()) { 430 // Use a strongly-typed unboxer, if possible. 431 fn = ValueConversions.unboxExact(wdst, strict); 432 } else { 433 // Examples: Object->int, Number->int, Comparable->int, Byte->int 434 // must include additional conversions 435 // src must be examined at runtime, to detect Byte, Character, etc. 436 fn = (strict 437 ? ValueConversions.unboxWiden(wdst) 438 : ValueConversions.unboxCast(wdst)); 439 } 440 } else { 441 // Simple reference conversion. 442 // Note: Do not check for a class hierarchy relation 443 // between src and dst. In all cases a 'null' argument 444 // will pass the cast conversion. 445 return dst; 446 } 447 assert(fn.type().parameterCount() <= 1) : "pc"+Arrays.asList(src.getSimpleName(), dst.getSimpleName(), fn); 448 return fn; 449 } 450 451 static MethodHandle makeVarargsCollector(MethodHandle target, Class<?> arrayType) { 452 MethodType type = target.type(); 453 int last = type.parameterCount() - 1; 454 if (type.parameterType(last) != arrayType) 455 target = target.asType(type.changeParameterType(last, arrayType)); 456 target = target.asFixedArity(); // make sure this attribute is turned off 457 return new AsVarargsCollector(target, arrayType); 458 } 459 460 @AOTSafeClassInitializer 461 static final class AsVarargsCollector extends DelegatingMethodHandle { 462 private final MethodHandle target; 463 private final Class<?> arrayType; 464 private MethodHandle asCollectorCache; 465 466 AsVarargsCollector(MethodHandle target, Class<?> arrayType) { 467 this(target.type(), target, arrayType); 468 } 469 AsVarargsCollector(MethodType type, MethodHandle target, Class<?> arrayType) { 470 super(type, target); 471 this.target = target; 472 this.arrayType = arrayType; 473 } 474 475 @Override 476 public boolean isVarargsCollector() { 477 return true; 478 } 479 480 @Override 481 protected MethodHandle getTarget() { 482 return target; 483 } 484 485 @Override 486 public MethodHandle asFixedArity() { 487 return target; 488 } 489 490 @Override 491 MethodHandle setVarargs(MemberName member) { 492 if (member.isVarargs()) return this; 493 return asFixedArity(); 494 } 495 496 @Override 497 public MethodHandle withVarargs(boolean makeVarargs) { 498 if (makeVarargs) return this; 499 return asFixedArity(); 500 } 501 502 @Override 503 public MethodHandle asTypeUncached(MethodType newType) { 504 MethodType type = this.type(); 505 int collectArg = type.parameterCount() - 1; 506 int newArity = newType.parameterCount(); 507 if (newArity == collectArg+1 && 508 type.parameterType(collectArg).isAssignableFrom(newType.parameterType(collectArg))) { 509 // if arity and trailing parameter are compatible, do normal thing 510 return asFixedArity().asType(newType); 511 } 512 // check cache 513 MethodHandle acc = asCollectorCache; 514 if (acc != null && acc.type().parameterCount() == newArity) 515 return acc.asType(newType); 516 // build and cache a collector 517 int arrayLength = newArity - collectArg; 518 MethodHandle collector; 519 try { 520 collector = asFixedArity().asCollector(arrayType, arrayLength); 521 assert(collector.type().parameterCount() == newArity) : "newArity="+newArity+" but collector="+collector; 522 } catch (IllegalArgumentException ex) { 523 throw new WrongMethodTypeException("cannot build collector", ex); 524 } 525 asCollectorCache = collector; 526 return collector.asType(newType); 527 } 528 529 @Override 530 boolean viewAsTypeChecks(MethodType newType, boolean strict) { 531 super.viewAsTypeChecks(newType, true); 532 if (strict) return true; 533 // extra assertion for non-strict checks: 534 assert (type().lastParameterType().getComponentType() 535 .isAssignableFrom( 536 newType.lastParameterType().getComponentType())) 537 : Arrays.asList(this, newType); 538 return true; 539 } 540 541 @Override 542 public Object invokeWithArguments(Object... arguments) throws Throwable { 543 MethodType type = this.type(); 544 int argc; 545 final int MAX_SAFE = 127; // 127 longs require 254 slots, which is safe to spread 546 if (arguments == null 547 || (argc = arguments.length) <= MAX_SAFE 548 || argc < type.parameterCount()) { 549 return super.invokeWithArguments(arguments); 550 } 551 552 // a jumbo invocation requires more explicit reboxing of the trailing arguments 553 int uncollected = type.parameterCount() - 1; 554 Class<?> elemType = arrayType.getComponentType(); 555 int collected = argc - uncollected; 556 Object collArgs = (elemType == Object.class) 557 ? new Object[collected] : Array.newInstance(elemType, collected); 558 if (!elemType.isPrimitive()) { 559 // simple cast: just do some casting 560 try { 561 System.arraycopy(arguments, uncollected, collArgs, 0, collected); 562 } catch (ArrayStoreException ex) { 563 return super.invokeWithArguments(arguments); 564 } 565 } else { 566 // corner case of flat array requires reflection (or specialized copy loop) 567 MethodHandle arraySetter = MethodHandles.arrayElementSetter(arrayType); 568 try { 569 for (int i = 0; i < collected; i++) { 570 arraySetter.invoke(collArgs, i, arguments[uncollected + i]); 571 } 572 } catch (WrongMethodTypeException|ClassCastException ex) { 573 return super.invokeWithArguments(arguments); 574 } 575 } 576 577 // chop the jumbo list down to size and call in non-varargs mode 578 Object[] newArgs = new Object[uncollected + 1]; 579 System.arraycopy(arguments, 0, newArgs, 0, uncollected); 580 newArgs[uncollected] = collArgs; 581 return asFixedArity().invokeWithArguments(newArgs); 582 } 583 } 584 585 static void checkSpreadArgument(Object av, int n) { 586 if (av == null && n == 0) { 587 return; 588 } else if (av == null) { 589 throw new NullPointerException("null array reference"); 590 } else if (av instanceof Object[] array) { 591 int len = array.length; 592 if (len == n) return; 593 } else { 594 int len = java.lang.reflect.Array.getLength(av); 595 if (len == n) return; 596 } 597 // fall through to error: 598 throw newIllegalArgumentException("array is not of length "+n); 599 } 600 601 @Hidden 602 static MethodHandle selectAlternative(boolean testResult, MethodHandle target, MethodHandle fallback) { 603 if (testResult) { 604 return target; 605 } else { 606 return fallback; 607 } 608 } 609 610 // Intrinsified by C2. Counters are used during parsing to calculate branch frequencies. 611 @Hidden 612 @jdk.internal.vm.annotation.IntrinsicCandidate 613 static boolean profileBoolean(boolean result, int[] counters) { 614 // Profile is int[2] where [0] and [1] correspond to false and true occurrences respectively. 615 int idx = result ? 1 : 0; 616 try { 617 counters[idx] = Math.addExact(counters[idx], 1); 618 } catch (ArithmeticException e) { 619 // Avoid continuous overflow by halving the problematic count. 620 counters[idx] = counters[idx] / 2; 621 } 622 return result; 623 } 624 625 // Intrinsified by C2. Returns true if obj is a compile-time constant. 626 @Hidden 627 @jdk.internal.vm.annotation.IntrinsicCandidate 628 static boolean isCompileConstant(Object obj) { 629 return false; 630 } 631 632 static MethodHandle makeGuardWithTest(MethodHandle test, 633 MethodHandle target, 634 MethodHandle fallback) { 635 MethodType type = target.type(); 636 assert(test.type().equals(type.changeReturnType(boolean.class)) && fallback.type().equals(type)); 637 MethodType basicType = type.basicType(); 638 LambdaForm form = makeGuardWithTestForm(basicType); 639 BoundMethodHandle mh; 640 try { 641 if (PROFILE_GWT) { 642 int[] counts = new int[2]; 643 mh = (BoundMethodHandle) 644 BoundMethodHandle.speciesData_LLLL().factory().invokeBasic(type, form, 645 (Object) test, (Object) profile(target), (Object) profile(fallback), counts); 646 } else { 647 mh = (BoundMethodHandle) 648 BoundMethodHandle.speciesData_LLL().factory().invokeBasic(type, form, 649 (Object) test, (Object) profile(target), (Object) profile(fallback)); 650 } 651 } catch (Throwable ex) { 652 throw uncaughtException(ex); 653 } 654 assert(mh.type() == type); 655 return mh; 656 } 657 658 659 static MethodHandle profile(MethodHandle target) { 660 if (DONT_INLINE_THRESHOLD >= 0) { 661 return makeBlockInliningWrapper(target); 662 } else { 663 return target; 664 } 665 } 666 667 /** 668 * Block inlining during JIT-compilation of a target method handle if it hasn't been invoked enough times. 669 * Corresponding LambdaForm has @DontInline when compiled into bytecode. 670 */ 671 static MethodHandle makeBlockInliningWrapper(MethodHandle target) { 672 LambdaForm lform; 673 if (DONT_INLINE_THRESHOLD > 0) { 674 lform = Makers.PRODUCE_BLOCK_INLINING_FORM.apply(target); 675 } else { 676 lform = Makers.PRODUCE_REINVOKER_FORM.apply(target); 677 } 678 return new CountingWrapper(target, lform, 679 Makers.PRODUCE_BLOCK_INLINING_FORM, Makers.PRODUCE_REINVOKER_FORM, 680 DONT_INLINE_THRESHOLD); 681 } 682 683 @AOTSafeClassInitializer 684 private static final class Makers { 685 /** Constructs reinvoker lambda form which block inlining during JIT-compilation for a particular method handle */ 686 static final Function<MethodHandle, LambdaForm> PRODUCE_BLOCK_INLINING_FORM = new Function<MethodHandle, LambdaForm>() { 687 @Override 688 public LambdaForm apply(MethodHandle target) { 689 return DelegatingMethodHandle.makeReinvokerForm(target, 690 MethodTypeForm.LF_DELEGATE_BLOCK_INLINING, CountingWrapper.class, false, 691 DelegatingMethodHandle.NF_getTarget, CountingWrapper.NF_maybeStopCounting); 692 } 693 }; 694 695 /** Constructs simple reinvoker lambda form for a particular method handle */ 696 static final Function<MethodHandle, LambdaForm> PRODUCE_REINVOKER_FORM = new Function<MethodHandle, LambdaForm>() { 697 @Override 698 public LambdaForm apply(MethodHandle target) { 699 return DelegatingMethodHandle.makeReinvokerForm(target, 700 MethodTypeForm.LF_DELEGATE, DelegatingMethodHandle.class, DelegatingMethodHandle.NF_getTarget); 701 } 702 }; 703 704 /** Maker of type-polymorphic varargs */ 705 static final ClassValue<MethodHandle[]> TYPED_COLLECTORS = new ClassValue<MethodHandle[]>() { 706 @Override 707 protected MethodHandle[] computeValue(Class<?> type) { 708 return new MethodHandle[MAX_JVM_ARITY + 1]; 709 } 710 }; 711 } 712 713 /** 714 * Counting method handle. It has 2 states: counting and non-counting. 715 * It is in counting state for the first n invocations and then transitions to non-counting state. 716 * Behavior in counting and non-counting states is determined by lambda forms produced by 717 * countingFormProducer & nonCountingFormProducer respectively. 718 */ 719 @AOTSafeClassInitializer 720 static final class CountingWrapper extends DelegatingMethodHandle { 721 private final MethodHandle target; 722 private int count; 723 private Function<MethodHandle, LambdaForm> countingFormProducer; 724 private Function<MethodHandle, LambdaForm> nonCountingFormProducer; 725 private volatile boolean isCounting; 726 727 private CountingWrapper(MethodHandle target, LambdaForm lform, 728 Function<MethodHandle, LambdaForm> countingFromProducer, 729 Function<MethodHandle, LambdaForm> nonCountingFormProducer, 730 int count) { 731 super(target.type(), lform); 732 this.target = target; 733 this.count = count; 734 this.countingFormProducer = countingFromProducer; 735 this.nonCountingFormProducer = nonCountingFormProducer; 736 this.isCounting = (count > 0); 737 } 738 739 @Hidden 740 @Override 741 protected MethodHandle getTarget() { 742 return target; 743 } 744 745 @Override 746 public MethodHandle asTypeUncached(MethodType newType) { 747 MethodHandle newTarget = target.asType(newType); 748 MethodHandle wrapper; 749 if (isCounting) { 750 LambdaForm lform; 751 lform = countingFormProducer.apply(newTarget); 752 wrapper = new CountingWrapper(newTarget, lform, countingFormProducer, nonCountingFormProducer, DONT_INLINE_THRESHOLD); 753 } else { 754 wrapper = newTarget; // no need for a counting wrapper anymore 755 } 756 return wrapper; 757 } 758 759 boolean countDown() { 760 int c = count; 761 target.maybeCustomize(); // customize if counting happens for too long 762 if (c <= 1) { 763 // Try to limit number of updates. MethodHandle.updateForm() doesn't guarantee LF update visibility. 764 if (isCounting) { 765 isCounting = false; 766 return true; 767 } else { 768 return false; 769 } 770 } else { 771 count = c - 1; 772 return false; 773 } 774 } 775 776 @Hidden 777 static void maybeStopCounting(Object o1) { 778 final CountingWrapper wrapper = (CountingWrapper) o1; 779 if (wrapper.countDown()) { 780 // Reached invocation threshold. Replace counting behavior with a non-counting one. 781 wrapper.updateForm(new Function<>() { 782 public LambdaForm apply(LambdaForm oldForm) { 783 LambdaForm lform = wrapper.nonCountingFormProducer.apply(wrapper.target); 784 lform.compileToBytecode(); // speed up warmup by avoiding LF interpretation again after transition 785 return lform; 786 }}); 787 } 788 } 789 790 static final NamedFunction NF_maybeStopCounting; 791 static { 792 Class<?> THIS_CLASS = CountingWrapper.class; 793 try { 794 NF_maybeStopCounting = new NamedFunction(THIS_CLASS.getDeclaredMethod("maybeStopCounting", Object.class)); 795 } catch (ReflectiveOperationException ex) { 796 throw newInternalError(ex); 797 } 798 } 799 } 800 801 static LambdaForm makeGuardWithTestForm(MethodType basicType) { 802 LambdaForm lform = basicType.form().cachedLambdaForm(MethodTypeForm.LF_GWT); 803 if (lform != null) return lform; 804 final int THIS_MH = 0; // the BMH_LLL 805 final int ARG_BASE = 1; // start of incoming arguments 806 final int ARG_LIMIT = ARG_BASE + basicType.parameterCount(); 807 int nameCursor = ARG_LIMIT; 808 final int GET_TEST = nameCursor++; 809 final int GET_TARGET = nameCursor++; 810 final int GET_FALLBACK = nameCursor++; 811 final int GET_COUNTERS = PROFILE_GWT ? nameCursor++ : -1; 812 final int CALL_TEST = nameCursor++; 813 final int PROFILE = (GET_COUNTERS != -1) ? nameCursor++ : -1; 814 final int TEST = nameCursor-1; // previous statement: either PROFILE or CALL_TEST 815 final int SELECT_ALT = nameCursor++; 816 final int CALL_TARGET = nameCursor++; 817 assert(CALL_TARGET == SELECT_ALT+1); // must be true to trigger IBG.emitSelectAlternative 818 819 Name[] names = invokeArguments(nameCursor - ARG_LIMIT, basicType); 820 821 BoundMethodHandle.SpeciesData data = 822 (GET_COUNTERS != -1) ? BoundMethodHandle.speciesData_LLLL() 823 : BoundMethodHandle.speciesData_LLL(); 824 names[THIS_MH] = names[THIS_MH].withConstraint(data); 825 names[GET_TEST] = new Name(data.getterFunction(0), names[THIS_MH]); 826 names[GET_TARGET] = new Name(data.getterFunction(1), names[THIS_MH]); 827 names[GET_FALLBACK] = new Name(data.getterFunction(2), names[THIS_MH]); 828 if (GET_COUNTERS != -1) { 829 names[GET_COUNTERS] = new Name(data.getterFunction(3), names[THIS_MH]); 830 } 831 Object[] invokeArgs = Arrays.copyOfRange(names, 0, ARG_LIMIT, Object[].class); 832 833 // call test 834 MethodType testType = basicType.changeReturnType(boolean.class).basicType(); 835 invokeArgs[0] = names[GET_TEST]; 836 names[CALL_TEST] = new Name(testType, invokeArgs); 837 838 // profile branch 839 if (PROFILE != -1) { 840 names[PROFILE] = new Name(getFunction(NF_profileBoolean), names[CALL_TEST], names[GET_COUNTERS]); 841 } 842 // call selectAlternative 843 names[SELECT_ALT] = new Name(new NamedFunction( 844 makeIntrinsic(getConstantHandle(MH_selectAlternative), Intrinsic.SELECT_ALTERNATIVE)), 845 names[TEST], names[GET_TARGET], names[GET_FALLBACK]); 846 847 // call target or fallback 848 invokeArgs[0] = names[SELECT_ALT]; 849 names[CALL_TARGET] = new Name(basicType, invokeArgs); 850 851 lform = LambdaForm.create(basicType.parameterCount() + 1, names, /*forceInline=*/true, Kind.GUARD); 852 853 return basicType.form().setCachedLambdaForm(MethodTypeForm.LF_GWT, lform); 854 } 855 856 /** 857 * The LambdaForm shape for catchException combinator is the following: 858 * <blockquote><pre>{@code 859 * guardWithCatch=Lambda(a0:L,a1:L,a2:L)=>{ 860 * t3:L=BoundMethodHandle$Species_LLLLL.argL0(a0:L); 861 * t4:L=BoundMethodHandle$Species_LLLLL.argL1(a0:L); 862 * t5:L=BoundMethodHandle$Species_LLLLL.argL2(a0:L); 863 * t6:L=BoundMethodHandle$Species_LLLLL.argL3(a0:L); 864 * t7:L=BoundMethodHandle$Species_LLLLL.argL4(a0:L); 865 * t8:L=MethodHandle.invokeBasic(t6:L,a1:L,a2:L); 866 * t9:L=MethodHandleImpl.guardWithCatch(t3:L,t4:L,t5:L,t8:L); 867 * t10:I=MethodHandle.invokeBasic(t7:L,t9:L);t10:I} 868 * }</pre></blockquote> 869 * 870 * argL0 and argL2 are target and catcher method handles. argL1 is exception class. 871 * argL3 and argL4 are auxiliary method handles: argL3 boxes arguments and wraps them into Object[] 872 * (ValueConversions.array()) and argL4 unboxes result if necessary (ValueConversions.unbox()). 873 * 874 * Having t8 and t10 passed outside and not hardcoded into a lambda form allows to share lambda forms 875 * among catchException combinators with the same basic type. 876 */ 877 private static LambdaForm makeGuardWithCatchForm(MethodType basicType) { 878 LambdaForm lform = basicType.form().cachedLambdaForm(MethodTypeForm.LF_GWC); 879 if (lform != null) { 880 return lform; 881 } 882 final int THIS_MH = 0; // the BMH_LLLLL 883 final int ARG_BASE = 1; // start of incoming arguments 884 final int ARG_LIMIT = ARG_BASE + basicType.parameterCount(); 885 886 int nameCursor = ARG_LIMIT; 887 final int GET_TARGET = nameCursor++; 888 final int GET_CLASS = nameCursor++; 889 final int GET_CATCHER = nameCursor++; 890 final int GET_COLLECT_ARGS = nameCursor++; 891 final int GET_UNBOX_RESULT = nameCursor++; 892 final int BOXED_ARGS = nameCursor++; 893 final int TRY_CATCH = nameCursor++; 894 final int UNBOX_RESULT = nameCursor++; 895 896 Name[] names = invokeArguments(nameCursor - ARG_LIMIT, basicType); 897 898 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLLLL(); 899 names[THIS_MH] = names[THIS_MH].withConstraint(data); 900 names[GET_TARGET] = new Name(data.getterFunction(0), names[THIS_MH]); 901 names[GET_CLASS] = new Name(data.getterFunction(1), names[THIS_MH]); 902 names[GET_CATCHER] = new Name(data.getterFunction(2), names[THIS_MH]); 903 names[GET_COLLECT_ARGS] = new Name(data.getterFunction(3), names[THIS_MH]); 904 names[GET_UNBOX_RESULT] = new Name(data.getterFunction(4), names[THIS_MH]); 905 906 // FIXME: rework argument boxing/result unboxing logic for LF interpretation 907 908 // t_{i}:L=MethodHandle.invokeBasic(collectArgs:L,a1:L,...); 909 MethodType collectArgsType = basicType.changeReturnType(Object.class); 910 MethodHandle invokeBasic = MethodHandles.basicInvoker(collectArgsType); 911 Object[] args = new Object[invokeBasic.type().parameterCount()]; 912 args[0] = names[GET_COLLECT_ARGS]; 913 System.arraycopy(names, ARG_BASE, args, 1, ARG_LIMIT-ARG_BASE); 914 names[BOXED_ARGS] = new Name(new NamedFunction(makeIntrinsic(invokeBasic, Intrinsic.GUARD_WITH_CATCH)), args); 915 916 // t_{i+1}:L=MethodHandleImpl.guardWithCatch(target:L,exType:L,catcher:L,t_{i}:L); 917 Object[] gwcArgs = new Object[] {names[GET_TARGET], names[GET_CLASS], names[GET_CATCHER], names[BOXED_ARGS]}; 918 names[TRY_CATCH] = new Name(getFunction(NF_guardWithCatch), gwcArgs); 919 920 // t_{i+2}:I=MethodHandle.invokeBasic(unbox:L,t_{i+1}:L); 921 MethodHandle invokeBasicUnbox = MethodHandles.basicInvoker(MethodType.methodType(basicType.rtype(), Object.class)); 922 Object[] unboxArgs = new Object[] {names[GET_UNBOX_RESULT], names[TRY_CATCH]}; 923 names[UNBOX_RESULT] = new Name(invokeBasicUnbox, unboxArgs); 924 925 lform = LambdaForm.create(basicType.parameterCount() + 1, names, Kind.GUARD_WITH_CATCH); 926 927 return basicType.form().setCachedLambdaForm(MethodTypeForm.LF_GWC, lform); 928 } 929 930 static MethodHandle makeGuardWithCatch(MethodHandle target, 931 Class<? extends Throwable> exType, 932 MethodHandle catcher) { 933 MethodType type = target.type(); 934 LambdaForm form = makeGuardWithCatchForm(type.basicType()); 935 936 // Prepare auxiliary method handles used during LambdaForm interpretation. 937 // Box arguments and wrap them into Object[]: ValueConversions.array(). 938 MethodType varargsType = type.changeReturnType(Object[].class); 939 MethodHandle collectArgs = varargsArray(type.parameterCount()).asType(varargsType); 940 MethodHandle unboxResult = unboxResultHandle(type.returnType()); 941 942 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLLLL(); 943 BoundMethodHandle mh; 944 try { 945 mh = (BoundMethodHandle) data.factory().invokeBasic(type, form, (Object) target, (Object) exType, 946 (Object) catcher, (Object) collectArgs, (Object) unboxResult); 947 } catch (Throwable ex) { 948 throw uncaughtException(ex); 949 } 950 assert(mh.type() == type); 951 return mh; 952 } 953 954 /** 955 * Intrinsified during LambdaForm compilation 956 * (see {@link InvokerBytecodeGenerator#emitGuardWithCatch emitGuardWithCatch}). 957 */ 958 @Hidden 959 static Object guardWithCatch(MethodHandle target, Class<? extends Throwable> exType, MethodHandle catcher, 960 Object... av) throws Throwable { 961 // Use asFixedArity() to avoid unnecessary boxing of last argument for VarargsCollector case. 962 try { 963 return target.asFixedArity().invokeWithArguments(av); 964 } catch (Throwable t) { 965 if (!exType.isInstance(t)) throw t; 966 return catcher.asFixedArity().invokeWithArguments(prepend(av, t)); 967 } 968 } 969 970 /** Prepend elements to an array. */ 971 @Hidden 972 private static Object[] prepend(Object[] array, Object... elems) { 973 int nArray = array.length; 974 int nElems = elems.length; 975 Object[] newArray = new Object[nArray + nElems]; 976 System.arraycopy(elems, 0, newArray, 0, nElems); 977 System.arraycopy(array, 0, newArray, nElems, nArray); 978 return newArray; 979 } 980 981 static MethodHandle throwException(MethodType type) { 982 assert(Throwable.class.isAssignableFrom(type.parameterType(0))); 983 int arity = type.parameterCount(); 984 if (arity > 1) { 985 MethodHandle mh = throwException(type.dropParameterTypes(1, arity)); 986 mh = MethodHandles.dropArgumentsTrusted(mh, 1, Arrays.copyOfRange(type.ptypes(), 1, arity)); 987 return mh; 988 } 989 return makePairwiseConvert(getFunction(NF_throwException).resolvedHandle(), type, false, true); 990 } 991 992 static <T extends Throwable> Void throwException(T t) throws T { throw t; } 993 994 static MethodHandle[] FAKE_METHOD_HANDLE_INVOKE = new MethodHandle[2]; 995 static MethodHandle fakeMethodHandleInvoke(MemberName method) { 996 assert(method.isMethodHandleInvoke()); 997 int idx = switch (method.getName()) { 998 case "invoke" -> 0; 999 case "invokeExact" -> 1; 1000 default -> throw new InternalError(method.getName()); 1001 }; 1002 MethodHandle mh = FAKE_METHOD_HANDLE_INVOKE[idx]; 1003 if (mh != null) return mh; 1004 MethodType type = MethodType.methodType(Object.class, UnsupportedOperationException.class, 1005 MethodHandle.class, Object[].class); 1006 mh = throwException(type); 1007 mh = mh.bindTo(new UnsupportedOperationException("cannot reflectively invoke MethodHandle")); 1008 if (!method.getInvocationType().equals(mh.type())) 1009 throw new InternalError(method.toString()); 1010 mh = mh.withInternalMemberName(method, false); 1011 mh = mh.withVarargs(true); 1012 assert(method.isVarargs()); 1013 FAKE_METHOD_HANDLE_INVOKE[idx] = mh; 1014 return mh; 1015 } 1016 static MethodHandle fakeVarHandleInvoke(MemberName method) { 1017 // TODO caching, is it necessary? 1018 MethodType type = MethodType.methodType(method.getMethodType().returnType(), 1019 UnsupportedOperationException.class, 1020 VarHandle.class, Object[].class); 1021 MethodHandle mh = throwException(type); 1022 mh = mh.bindTo(new UnsupportedOperationException("cannot reflectively invoke VarHandle")); 1023 if (!method.getInvocationType().equals(mh.type())) 1024 throw new InternalError(method.toString()); 1025 mh = mh.withInternalMemberName(method, false); 1026 mh = mh.asVarargsCollector(Object[].class); 1027 assert(method.isVarargs()); 1028 return mh; 1029 } 1030 1031 /** 1032 * Create an alias for the method handle which, when called, 1033 * appears to be called from the same class loader and protection domain 1034 * as hostClass. 1035 * This is an expensive no-op unless the method which is called 1036 * is sensitive to its caller. A small number of system methods 1037 * are in this category, including Class.forName and Method.invoke. 1038 */ 1039 static MethodHandle bindCaller(MethodHandle mh, Class<?> hostClass) { 1040 return BindCaller.bindCaller(mh, hostClass); 1041 } 1042 1043 // Put the whole mess into its own nested class. 1044 // That way we can lazily load the code and set up the constants. 1045 @AOTSafeClassInitializer 1046 private static class BindCaller { 1047 1048 private static final ClassDesc CD_Object_array = ConstantUtils.CD_Object_array; 1049 private static final MethodType INVOKER_MT = MethodType.methodType(Object.class, MethodHandle.class, Object[].class); 1050 private static final MethodType REFLECT_INVOKER_MT = MethodType.methodType(Object.class, MethodHandle.class, Object.class, Object[].class); 1051 1052 static MethodHandle bindCaller(MethodHandle mh, Class<?> hostClass) { 1053 // Code in the boot layer should now be careful while creating method handles or 1054 // functional interface instances created from method references to @CallerSensitive methods, 1055 // it needs to be ensured the handles or interface instances are kept safe and are not passed 1056 // from the boot layer to untrusted code. 1057 if (hostClass == null 1058 || (hostClass.isArray() || 1059 hostClass.isPrimitive() || 1060 hostClass.getName().startsWith("java.lang.invoke."))) { 1061 throw new InternalError(); // does not happen, and should not anyway 1062 } 1063 1064 MemberName member = mh.internalMemberName(); 1065 if (member != null) { 1066 // Look up the CSM adapter method with the same method name 1067 // but with an additional caller class parameter. If present, 1068 // bind the adapter's method handle with the lookup class as 1069 // the caller class argument 1070 MemberName csmAdapter = IMPL_LOOKUP.resolveOrNull(member.getReferenceKind(), 1071 new MemberName(member.getDeclaringClass(), 1072 member.getName(), 1073 member.getMethodType().appendParameterTypes(Class.class), 1074 member.getReferenceKind())); 1075 if (csmAdapter != null) { 1076 assert !csmAdapter.isCallerSensitive(); 1077 MethodHandle dmh = DirectMethodHandle.make(csmAdapter); 1078 dmh = MethodHandles.insertArguments(dmh, dmh.type().parameterCount() - 1, hostClass); 1079 dmh = new WrappedMember(dmh, mh.type(), member, mh.isInvokeSpecial(), hostClass); 1080 return dmh; 1081 } 1082 } 1083 1084 // If no adapter method for CSM with an additional Class parameter 1085 // is present, then inject an invoker class that is the caller 1086 // invoking the method handle of the CSM 1087 try { 1088 return bindCallerWithInjectedInvoker(mh, hostClass); 1089 } catch (ReflectiveOperationException ex) { 1090 throw uncaughtException(ex); 1091 } 1092 } 1093 1094 private static MethodHandle bindCallerWithInjectedInvoker(MethodHandle mh, Class<?> hostClass) 1095 throws ReflectiveOperationException 1096 { 1097 // For simplicity, convert mh to a varargs-like method. 1098 MethodHandle vamh = prepareForInvoker(mh); 1099 // Cache the result of makeInjectedInvoker once per argument class. 1100 MethodHandle bccInvoker = CV_makeInjectedInvoker.get(hostClass).invoker(); 1101 return restoreToType(bccInvoker.bindTo(vamh), mh, hostClass); 1102 } 1103 1104 private static Class<?> makeInjectedInvoker(Class<?> targetClass) { 1105 /* 1106 * The invoker class defined to the same class loader as the lookup class 1107 * but in an unnamed package so that the class bytes can be cached and 1108 * reused for any @CSM. 1109 * 1110 * @CSM must be public and exported if called by any module. 1111 */ 1112 String name = targetClass.getName() + "$$InjectedInvoker"; 1113 if (targetClass.isHidden()) { 1114 // use the original class name 1115 name = name.replace('/', '_'); 1116 } 1117 name = name.replace('.', '/'); 1118 Class<?> invokerClass = new Lookup(targetClass) 1119 .makeHiddenClassDefiner(name, INJECTED_INVOKER_TEMPLATE, dumper(), NESTMATE_CLASS) 1120 .defineClass(true, targetClass); 1121 assert checkInjectedInvoker(targetClass, invokerClass); 1122 return invokerClass; 1123 } 1124 1125 private static ClassValue<InjectedInvokerHolder> CV_makeInjectedInvoker = new ClassValue<>() { 1126 @Override 1127 protected InjectedInvokerHolder computeValue(Class<?> hostClass) { 1128 return new InjectedInvokerHolder(makeInjectedInvoker(hostClass)); 1129 } 1130 }; 1131 1132 /* 1133 * Returns a method handle of an invoker class injected for reflection 1134 * implementation use with the following signature: 1135 * reflect_invoke_V(MethodHandle mh, Object target, Object[] args) 1136 * 1137 * Method::invoke on a caller-sensitive method will call 1138 * MethodAccessorImpl::invoke(Object, Object[]) through reflect_invoke_V 1139 * target.csm(args) 1140 * NativeMethodAccessorImpl::invoke(target, args) 1141 * MethodAccessImpl::invoke(target, args) 1142 * InjectedInvoker::reflect_invoke_V(vamh, target, args); 1143 * method::invoke(target, args) 1144 * p.Foo::m 1145 * 1146 * An injected invoker class is a hidden class which has the same 1147 * defining class loader, runtime package, and protection domain 1148 * as the given caller class. 1149 */ 1150 static MethodHandle reflectiveInvoker(Class<?> caller) { 1151 return BindCaller.CV_makeInjectedInvoker.get(caller).reflectInvoker(); 1152 } 1153 1154 @AOTSafeClassInitializer 1155 private static final class InjectedInvokerHolder { 1156 private final Class<?> invokerClass; 1157 // lazily resolved and cached DMH(s) of invoke_V methods 1158 private MethodHandle invoker; 1159 private MethodHandle reflectInvoker; 1160 1161 private InjectedInvokerHolder(Class<?> invokerClass) { 1162 this.invokerClass = invokerClass; 1163 } 1164 1165 private MethodHandle invoker() { 1166 var mh = invoker; 1167 if (mh == null) { 1168 try { 1169 invoker = mh = IMPL_LOOKUP.findStatic(invokerClass, "invoke_V", INVOKER_MT); 1170 } catch (Error | RuntimeException ex) { 1171 throw ex; 1172 } catch (Throwable ex) { 1173 throw new InternalError(ex); 1174 } 1175 } 1176 return mh; 1177 } 1178 1179 private MethodHandle reflectInvoker() { 1180 var mh = reflectInvoker; 1181 if (mh == null) { 1182 try { 1183 reflectInvoker = mh = IMPL_LOOKUP.findStatic(invokerClass, "reflect_invoke_V", REFLECT_INVOKER_MT); 1184 } catch (Error | RuntimeException ex) { 1185 throw ex; 1186 } catch (Throwable ex) { 1187 throw new InternalError(ex); 1188 } 1189 } 1190 return mh; 1191 } 1192 } 1193 1194 // Adapt mh so that it can be called directly from an injected invoker: 1195 private static MethodHandle prepareForInvoker(MethodHandle mh) { 1196 mh = mh.asFixedArity(); 1197 MethodType mt = mh.type(); 1198 int arity = mt.parameterCount(); 1199 MethodHandle vamh = mh.asType(mt.generic()); 1200 vamh.internalForm().compileToBytecode(); // eliminate LFI stack frames 1201 vamh = vamh.asSpreader(Object[].class, arity); 1202 vamh.internalForm().compileToBytecode(); // eliminate LFI stack frames 1203 return vamh; 1204 } 1205 1206 // Undo the adapter effect of prepareForInvoker: 1207 private static MethodHandle restoreToType(MethodHandle vamh, 1208 MethodHandle original, 1209 Class<?> hostClass) { 1210 MethodType type = original.type(); 1211 MethodHandle mh = vamh.asCollector(Object[].class, type.parameterCount()); 1212 MemberName member = original.internalMemberName(); 1213 mh = mh.asType(type); 1214 mh = new WrappedMember(mh, type, member, original.isInvokeSpecial(), hostClass); 1215 return mh; 1216 } 1217 1218 private static boolean checkInjectedInvoker(Class<?> hostClass, Class<?> invokerClass) { 1219 assert (hostClass.getClassLoader() == invokerClass.getClassLoader()) : hostClass.getName()+" (CL)"; 1220 assert (hostClass.getProtectionDomain() == invokerClass.getProtectionDomain()) : hostClass.getName()+" (PD)"; 1221 try { 1222 // Test the invoker to ensure that it really injects into the right place. 1223 MethodHandle invoker = IMPL_LOOKUP.findStatic(invokerClass, "invoke_V", INVOKER_MT); 1224 MethodHandle vamh = prepareForInvoker(MH_checkCallerClass); 1225 return (boolean)invoker.invoke(vamh, new Object[]{ invokerClass }); 1226 } catch (Error|RuntimeException ex) { 1227 throw ex; 1228 } catch (Throwable ex) { 1229 throw new InternalError(ex); 1230 } 1231 } 1232 1233 private static final MethodHandle MH_checkCallerClass; 1234 static { 1235 final Class<?> THIS_CLASS = BindCaller.class; 1236 assert(checkCallerClass(THIS_CLASS)); 1237 try { 1238 MH_checkCallerClass = IMPL_LOOKUP 1239 .findStatic(THIS_CLASS, "checkCallerClass", 1240 MethodType.methodType(boolean.class, Class.class)); 1241 assert((boolean) MH_checkCallerClass.invokeExact(THIS_CLASS)); 1242 } catch (Throwable ex) { 1243 throw new InternalError(ex); 1244 } 1245 } 1246 1247 @CallerSensitive 1248 @ForceInline // to ensure Reflection.getCallerClass optimization 1249 private static boolean checkCallerClass(Class<?> expected) { 1250 // This method is called via MH_checkCallerClass and so it's correct to ask for the immediate caller here. 1251 Class<?> actual = Reflection.getCallerClass(); 1252 if (actual != expected) 1253 throw new InternalError("found " + actual.getName() + ", expected " + expected.getName()); 1254 return true; 1255 } 1256 1257 private static final byte[] INJECTED_INVOKER_TEMPLATE = generateInvokerTemplate(); 1258 1259 /** Produces byte code for a class that is used as an injected invoker. */ 1260 private static byte[] generateInvokerTemplate() { 1261 // private static class InjectedInvoker { 1262 // /* this is used to wrap DMH(s) of caller-sensitive methods */ 1263 // @Hidden 1264 // static Object invoke_V(MethodHandle vamh, Object[] args) throws Throwable { 1265 // return vamh.invokeExact(args); 1266 // } 1267 // /* this is used in caller-sensitive reflective method accessor */ 1268 // @Hidden 1269 // static Object reflect_invoke_V(MethodHandle vamh, Object target, Object[] args) throws Throwable { 1270 // return vamh.invokeExact(target, args); 1271 // } 1272 // } 1273 // } 1274 return ClassFile.of().build(ClassOrInterfaceDescImpl.ofValidated("LInjectedInvoker;"), clb -> clb 1275 .withFlags(ACC_PRIVATE | ACC_SUPER) 1276 .withMethodBody( 1277 "invoke_V", 1278 MethodTypeDescImpl.ofValidated(CD_Object, CD_MethodHandle, CD_Object_array), 1279 ACC_STATIC, 1280 cob -> cob.aload(0) 1281 .aload(1) 1282 .invokevirtual(CD_MethodHandle, "invokeExact", MethodTypeDescImpl.ofValidated(CD_Object, CD_Object_array)) 1283 .areturn()) 1284 .withMethodBody( 1285 "reflect_invoke_V", 1286 MethodTypeDescImpl.ofValidated(CD_Object, CD_MethodHandle, CD_Object, CD_Object_array), 1287 ACC_STATIC, 1288 cob -> cob.aload(0) 1289 .aload(1) 1290 .aload(2) 1291 .invokevirtual(CD_MethodHandle, "invokeExact", MethodTypeDescImpl.ofValidated(CD_Object, CD_Object, CD_Object_array)) 1292 .areturn())); 1293 } 1294 } 1295 1296 /** This subclass allows a wrapped method handle to be re-associated with an arbitrary member name. */ 1297 @AOTSafeClassInitializer 1298 static final class WrappedMember extends DelegatingMethodHandle { 1299 private final MethodHandle target; 1300 private final MemberName member; 1301 private final Class<?> callerClass; 1302 private final boolean isInvokeSpecial; 1303 1304 private WrappedMember(MethodHandle target, MethodType type, 1305 MemberName member, boolean isInvokeSpecial, 1306 Class<?> callerClass) { 1307 super(type, target); 1308 this.target = target; 1309 this.member = member; 1310 this.callerClass = callerClass; 1311 this.isInvokeSpecial = isInvokeSpecial; 1312 } 1313 1314 @Override 1315 MemberName internalMemberName() { 1316 return member; 1317 } 1318 @Override 1319 Class<?> internalCallerClass() { 1320 return callerClass; 1321 } 1322 @Override 1323 boolean isInvokeSpecial() { 1324 return isInvokeSpecial; 1325 } 1326 @Override 1327 protected MethodHandle getTarget() { 1328 return target; 1329 } 1330 @Override 1331 public MethodHandle asTypeUncached(MethodType newType) { 1332 // This MH is an alias for target, except for the MemberName 1333 // Drop the MemberName if there is any conversion. 1334 return target.asType(newType); 1335 } 1336 } 1337 1338 static MethodHandle makeWrappedMember(MethodHandle target, MemberName member, boolean isInvokeSpecial) { 1339 if (member.equals(target.internalMemberName()) && isInvokeSpecial == target.isInvokeSpecial()) 1340 return target; 1341 return new WrappedMember(target, target.type(), member, isInvokeSpecial, null); 1342 } 1343 1344 /** Intrinsic IDs */ 1345 /*non-public*/ 1346 enum Intrinsic { 1347 SELECT_ALTERNATIVE, 1348 GUARD_WITH_CATCH, 1349 TRY_FINALLY, 1350 TABLE_SWITCH, 1351 LOOP, 1352 ARRAY_LOAD, 1353 ARRAY_STORE, 1354 ARRAY_LENGTH, 1355 IDENTITY, 1356 NONE // no intrinsic associated 1357 } 1358 1359 /** Mark arbitrary method handle as intrinsic. 1360 * InvokerBytecodeGenerator uses this info to produce more efficient bytecode shape. */ 1361 @AOTSafeClassInitializer 1362 static final class IntrinsicMethodHandle extends DelegatingMethodHandle { 1363 private final MethodHandle target; 1364 private final Intrinsic intrinsicName; 1365 private final Object intrinsicData; 1366 1367 IntrinsicMethodHandle(MethodHandle target, Intrinsic intrinsicName) { 1368 this(target, intrinsicName, null); 1369 } 1370 1371 IntrinsicMethodHandle(MethodHandle target, Intrinsic intrinsicName, Object intrinsicData) { 1372 super(target.type(), target); 1373 this.target = target; 1374 this.intrinsicName = intrinsicName; 1375 this.intrinsicData = intrinsicData; 1376 } 1377 1378 @Override 1379 protected MethodHandle getTarget() { 1380 return target; 1381 } 1382 1383 @Override 1384 Intrinsic intrinsicName() { 1385 return intrinsicName; 1386 } 1387 1388 @Override 1389 Object intrinsicData() { 1390 return intrinsicData; 1391 } 1392 1393 @Override 1394 public MethodHandle asTypeUncached(MethodType newType) { 1395 // This MH is an alias for target, except for the intrinsic name 1396 // Drop the name if there is any conversion. 1397 return target.asType(newType); 1398 } 1399 1400 @Override 1401 String internalProperties() { 1402 return super.internalProperties() + 1403 "\n& Intrinsic="+intrinsicName; 1404 } 1405 1406 @Override 1407 public MethodHandle asCollector(Class<?> arrayType, int arrayLength) { 1408 if (intrinsicName == Intrinsic.IDENTITY) { 1409 MethodType resultType = type().asCollectorType(arrayType, type().parameterCount() - 1, arrayLength); 1410 MethodHandle newArray = MethodHandleImpl.varargsArray(arrayType, arrayLength); 1411 return newArray.asType(resultType); 1412 } 1413 return super.asCollector(arrayType, arrayLength); 1414 } 1415 } 1416 1417 static MethodHandle makeIntrinsic(MethodHandle target, Intrinsic intrinsicName) { 1418 return makeIntrinsic(target, intrinsicName, null); 1419 } 1420 1421 static MethodHandle makeIntrinsic(MethodHandle target, Intrinsic intrinsicName, Object intrinsicData) { 1422 if (intrinsicName == target.intrinsicName()) 1423 return target; 1424 return new IntrinsicMethodHandle(target, intrinsicName, intrinsicData); 1425 } 1426 1427 static MethodHandle makeIntrinsic(MethodType type, LambdaForm form, Intrinsic intrinsicName) { 1428 return new IntrinsicMethodHandle(SimpleMethodHandle.make(type, form), intrinsicName); 1429 } 1430 1431 private static final @Stable MethodHandle[] ARRAYS = new MethodHandle[MAX_ARITY + 1]; 1432 1433 /** Return a method handle that takes the indicated number of Object 1434 * arguments and returns an Object array of them, as if for varargs. 1435 */ 1436 static MethodHandle varargsArray(int nargs) { 1437 MethodHandle mh = ARRAYS[nargs]; 1438 if (mh != null) { 1439 return mh; 1440 } 1441 mh = makeCollector(Object[].class, nargs); 1442 assert(assertCorrectArity(mh, nargs)); 1443 return ARRAYS[nargs] = mh; 1444 } 1445 1446 /** Return a method handle that takes the indicated number of 1447 * typed arguments and returns an array of them. 1448 * The type argument is the array type. 1449 */ 1450 static MethodHandle varargsArray(Class<?> arrayType, int nargs) { 1451 Class<?> elemType = arrayType.getComponentType(); 1452 if (elemType == null) throw new IllegalArgumentException("not an array: "+arrayType); 1453 if (nargs >= MAX_JVM_ARITY/2 - 1) { 1454 int slots = nargs; 1455 final int MAX_ARRAY_SLOTS = MAX_JVM_ARITY - 1; // 1 for receiver MH 1456 if (slots <= MAX_ARRAY_SLOTS && elemType.isPrimitive()) 1457 slots *= Wrapper.forPrimitiveType(elemType).stackSlots(); 1458 if (slots > MAX_ARRAY_SLOTS) 1459 throw new IllegalArgumentException("too many arguments: "+arrayType.getSimpleName()+", length "+nargs); 1460 } 1461 if (elemType == Object.class) 1462 return varargsArray(nargs); 1463 // other cases: primitive arrays, subtypes of Object[] 1464 MethodHandle cache[] = Makers.TYPED_COLLECTORS.get(elemType); 1465 MethodHandle mh = nargs < cache.length ? cache[nargs] : null; 1466 if (mh != null) return mh; 1467 mh = makeCollector(arrayType, nargs); 1468 assert(assertCorrectArity(mh, nargs)); 1469 if (nargs < cache.length) 1470 cache[nargs] = mh; 1471 return mh; 1472 } 1473 1474 private static boolean assertCorrectArity(MethodHandle mh, int arity) { 1475 assert(mh.type().parameterCount() == arity) : "arity != "+arity+": "+mh; 1476 return true; 1477 } 1478 1479 static final int MAX_JVM_ARITY = 255; // limit imposed by the JVM 1480 1481 /*non-public*/ 1482 static void assertSame(Object mh1, Object mh2) { 1483 if (mh1 != mh2) { 1484 String msg = String.format("mh1 != mh2: mh1 = %s (form: %s); mh2 = %s (form: %s)", 1485 mh1, ((MethodHandle)mh1).form, 1486 mh2, ((MethodHandle)mh2).form); 1487 throw newInternalError(msg); 1488 } 1489 } 1490 1491 // Local constant functions: 1492 1493 /* non-public */ 1494 static final byte NF_checkSpreadArgument = 0, 1495 NF_guardWithCatch = 1, 1496 NF_throwException = 2, 1497 NF_tryFinally = 3, 1498 NF_loop = 4, 1499 NF_profileBoolean = 5, 1500 NF_tableSwitch = 6, 1501 NF_LIMIT = 7; 1502 1503 private static final @Stable NamedFunction[] NFS = new NamedFunction[NF_LIMIT]; 1504 1505 static NamedFunction getFunction(byte func) { 1506 NamedFunction nf = NFS[func]; 1507 if (nf != null) { 1508 return nf; 1509 } 1510 return NFS[func] = createFunction(func); 1511 } 1512 1513 private static NamedFunction createFunction(byte func) { 1514 try { 1515 return switch (func) { 1516 case NF_checkSpreadArgument -> new NamedFunction(MethodHandleImpl.class 1517 .getDeclaredMethod("checkSpreadArgument", Object.class, int.class)); 1518 case NF_guardWithCatch -> new NamedFunction(MethodHandleImpl.class 1519 .getDeclaredMethod("guardWithCatch", MethodHandle.class, Class.class, 1520 MethodHandle.class, Object[].class)); 1521 case NF_tryFinally -> new NamedFunction(MethodHandleImpl.class 1522 .getDeclaredMethod("tryFinally", MethodHandle.class, MethodHandle.class, Object[].class)); 1523 case NF_loop -> new NamedFunction(MethodHandleImpl.class 1524 .getDeclaredMethod("loop", BasicType[].class, LoopClauses.class, Object[].class)); 1525 case NF_throwException -> new NamedFunction(MethodHandleImpl.class 1526 .getDeclaredMethod("throwException", Throwable.class)); 1527 case NF_profileBoolean -> new NamedFunction(MethodHandleImpl.class 1528 .getDeclaredMethod("profileBoolean", boolean.class, int[].class)); 1529 case NF_tableSwitch -> new NamedFunction(MethodHandleImpl.class 1530 .getDeclaredMethod("tableSwitch", int.class, MethodHandle.class, CasesHolder.class, Object[].class)); 1531 default -> throw new InternalError("Undefined function: " + func); 1532 }; 1533 } catch (ReflectiveOperationException ex) { 1534 throw newInternalError(ex); 1535 } 1536 } 1537 1538 static { 1539 runtimeSetup(); 1540 } 1541 1542 @AOTRuntimeSetup 1543 private static void runtimeSetup() { 1544 SharedSecrets.setJavaLangInvokeAccess(new JavaLangInvokeAccess() { 1545 @Override 1546 public Class<?> getDeclaringClass(Object rmname) { 1547 ResolvedMethodName method = (ResolvedMethodName)rmname; 1548 return method.declaringClass(); 1549 } 1550 1551 @Override 1552 public MethodType getMethodType(String descriptor, ClassLoader loader) { 1553 return MethodType.fromDescriptor(descriptor, loader); 1554 } 1555 1556 public boolean isCallerSensitive(int flags) { 1557 return (flags & MN_CALLER_SENSITIVE) == MN_CALLER_SENSITIVE; 1558 } 1559 1560 public boolean isHiddenMember(int flags) { 1561 return (flags & MN_HIDDEN_MEMBER) == MN_HIDDEN_MEMBER; 1562 } 1563 1564 public boolean isNullRestrictedField(MethodHandle mh) { 1565 var memberName = mh.internalMemberName(); 1566 assert memberName.isField(); 1567 return memberName.isNullRestricted(); 1568 } 1569 1570 @Override 1571 public Map<String, byte[]> generateHolderClasses(Stream<String> traces) { 1572 return GenerateJLIClassesHelper.generateHolderClasses(traces); 1573 } 1574 1575 @Override 1576 public VarHandle memorySegmentViewHandle(Class<?> carrier, MemoryLayout enclosing, long alignmentMask, ByteOrder order, boolean constantOffset, long offset) { 1577 return VarHandles.memorySegmentViewHandle(carrier, enclosing, alignmentMask, constantOffset, offset, order); 1578 } 1579 1580 @Override 1581 public MethodHandle nativeMethodHandle(NativeEntryPoint nep) { 1582 return NativeMethodHandle.make(nep); 1583 } 1584 1585 @Override 1586 public VarHandle filterValue(VarHandle target, MethodHandle filterToTarget, MethodHandle filterFromTarget) { 1587 return VarHandles.filterValue(target, filterToTarget, filterFromTarget); 1588 } 1589 1590 @Override 1591 public VarHandle filterCoordinates(VarHandle target, int pos, MethodHandle... filters) { 1592 return VarHandles.filterCoordinates(target, pos, filters); 1593 } 1594 1595 @Override 1596 public VarHandle dropCoordinates(VarHandle target, int pos, Class<?>... valueTypes) { 1597 return VarHandles.dropCoordinates(target, pos, valueTypes); 1598 } 1599 1600 @Override 1601 public VarHandle permuteCoordinates(VarHandle target, List<Class<?>> newCoordinates, int... reorder) { 1602 return VarHandles.permuteCoordinates(target, newCoordinates, reorder); 1603 } 1604 1605 @Override 1606 public VarHandle collectCoordinates(VarHandle target, int pos, MethodHandle filter) { 1607 return VarHandles.collectCoordinates(target, pos, filter); 1608 } 1609 1610 @Override 1611 public VarHandle insertCoordinates(VarHandle target, int pos, Object... values) { 1612 return VarHandles.insertCoordinates(target, pos, values); 1613 } 1614 1615 1616 @Override 1617 public MethodHandle unreflectConstructor(Constructor<?> ctor) throws IllegalAccessException { 1618 return IMPL_LOOKUP.unreflectConstructor(ctor); 1619 } 1620 1621 @Override 1622 public MethodHandle unreflectField(Field field, boolean isSetter) throws IllegalAccessException { 1623 return isSetter ? IMPL_LOOKUP.unreflectSetter(field) : IMPL_LOOKUP.unreflectGetter(field); 1624 } 1625 1626 @Override 1627 public MethodHandle findVirtual(Class<?> defc, String name, MethodType type) throws IllegalAccessException { 1628 try { 1629 return IMPL_LOOKUP.findVirtual(defc, name, type); 1630 } catch (NoSuchMethodException e) { 1631 return null; 1632 } 1633 } 1634 1635 @Override 1636 public MethodHandle findStatic(Class<?> defc, String name, MethodType type) throws IllegalAccessException { 1637 try { 1638 return IMPL_LOOKUP.findStatic(defc, name, type); 1639 } catch (NoSuchMethodException e) { 1640 return null; 1641 } 1642 } 1643 1644 @Override 1645 public MethodHandle reflectiveInvoker(Class<?> caller) { 1646 Objects.requireNonNull(caller); 1647 return BindCaller.reflectiveInvoker(caller); 1648 } 1649 1650 @Override 1651 public Class<?>[] exceptionTypes(MethodHandle handle) { 1652 return VarHandles.exceptionTypes(handle); 1653 } 1654 1655 @Override 1656 public MethodHandle serializableConstructor(Class<?> decl, Constructor<?> ctorToCall) throws IllegalAccessException { 1657 return IMPL_LOOKUP.serializableConstructor(decl, ctorToCall); 1658 } 1659 1660 @Override 1661 public MethodHandle assertAsType(MethodHandle original, MethodType assertedType) { 1662 return original.viewAsType(assertedType, false); 1663 } 1664 }); 1665 } 1666 1667 /** Result unboxing: ValueConversions.unbox() OR ValueConversions.identity() OR ValueConversions.ignore(). */ 1668 private static MethodHandle unboxResultHandle(Class<?> returnType) { 1669 if (returnType.isPrimitive()) { 1670 if (returnType == void.class) { 1671 return ValueConversions.ignore(); 1672 } else { 1673 Wrapper w = Wrapper.forPrimitiveType(returnType); 1674 return ValueConversions.unboxExact(w); 1675 } 1676 } else { 1677 return MethodHandles.identity(Object.class); 1678 } 1679 } 1680 1681 /** 1682 * Assembles a loop method handle from the given handles and type information. 1683 * 1684 * @param tloop the return type of the loop. 1685 * @param targs types of the arguments to be passed to the loop. 1686 * @param init sanitized array of initializers for loop-local variables. 1687 * @param step sanitized array of loop bodies. 1688 * @param pred sanitized array of predicates. 1689 * @param fini sanitized array of loop finalizers. 1690 * 1691 * @return a handle that, when invoked, will execute the loop. 1692 */ 1693 static MethodHandle makeLoop(Class<?> tloop, List<Class<?>> targs, List<MethodHandle> init, List<MethodHandle> step, 1694 List<MethodHandle> pred, List<MethodHandle> fini) { 1695 MethodType type = MethodType.methodType(tloop, targs); 1696 BasicType[] initClauseTypes = 1697 init.stream().map(h -> h.type().returnType()).map(BasicType::basicType).toArray(BasicType[]::new); 1698 LambdaForm form = makeLoopForm(type.basicType(), initClauseTypes); 1699 1700 // Prepare auxiliary method handles used during LambdaForm interpretation. 1701 // Box arguments and wrap them into Object[]: ValueConversions.array(). 1702 MethodType varargsType = type.changeReturnType(Object[].class); 1703 MethodHandle collectArgs = varargsArray(type.parameterCount()).asType(varargsType); 1704 MethodHandle unboxResult = unboxResultHandle(tloop); 1705 1706 LoopClauses clauseData = 1707 new LoopClauses(new MethodHandle[][]{toArray(init), toArray(step), toArray(pred), toArray(fini)}); 1708 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLL(); 1709 BoundMethodHandle mh; 1710 try { 1711 mh = (BoundMethodHandle) data.factory().invokeBasic(type, form, (Object) clauseData, 1712 (Object) collectArgs, (Object) unboxResult); 1713 } catch (Throwable ex) { 1714 throw uncaughtException(ex); 1715 } 1716 assert(mh.type() == type); 1717 return mh; 1718 } 1719 1720 private static MethodHandle[] toArray(List<MethodHandle> l) { 1721 return l.toArray(new MethodHandle[0]); 1722 } 1723 1724 /** 1725 * Loops introduce some complexity as they can have additional local state. Hence, LambdaForms for loops are 1726 * generated from a template. The LambdaForm template shape for the loop combinator is as follows (assuming one 1727 * reference parameter passed in {@code a1}, and a reference return type, with the return value represented by 1728 * {@code t12}): 1729 * <blockquote><pre>{@code 1730 * loop=Lambda(a0:L,a1:L)=>{ 1731 * t2:L=BoundMethodHandle$Species_L3.argL0(a0:L); // LoopClauses holding init, step, pred, fini handles 1732 * t3:L=BoundMethodHandle$Species_L3.argL1(a0:L); // helper handle to box the arguments into an Object[] 1733 * t4:L=BoundMethodHandle$Species_L3.argL2(a0:L); // helper handle to unbox the result 1734 * t5:L=MethodHandle.invokeBasic(t3:L,a1:L); // box the arguments into an Object[] 1735 * t6:L=MethodHandleImpl.loop(null,t2:L,t3:L); // call the loop executor 1736 * t7:L=MethodHandle.invokeBasic(t4:L,t6:L);t7:L} // unbox the result; return the result 1737 * }</pre></blockquote> 1738 * <p> 1739 * {@code argL0} is a LoopClauses instance holding, in a 2-dimensional array, the init, step, pred, and fini method 1740 * handles. {@code argL1} and {@code argL2} are auxiliary method handles: {@code argL1} boxes arguments and wraps 1741 * them into {@code Object[]} ({@code ValueConversions.array()}), and {@code argL2} unboxes the result if necessary 1742 * ({@code ValueConversions.unbox()}). 1743 * <p> 1744 * Having {@code t3} and {@code t4} passed in via a BMH and not hardcoded in the lambda form allows to share lambda 1745 * forms among loop combinators with the same basic type. 1746 * <p> 1747 * The above template is instantiated by using the {@link LambdaFormEditor} to replace the {@code null} argument to 1748 * the {@code loop} invocation with the {@code BasicType} array describing the loop clause types. This argument is 1749 * ignored in the loop invoker, but will be extracted and used in {@linkplain InvokerBytecodeGenerator#emitLoop(int) 1750 * bytecode generation}. 1751 */ 1752 private static LambdaForm makeLoopForm(MethodType basicType, BasicType[] localVarTypes) { 1753 final int THIS_MH = 0; // the BMH_LLL 1754 final int ARG_BASE = 1; // start of incoming arguments 1755 final int ARG_LIMIT = ARG_BASE + basicType.parameterCount(); 1756 1757 int nameCursor = ARG_LIMIT; 1758 final int GET_CLAUSE_DATA = nameCursor++; 1759 final int GET_COLLECT_ARGS = nameCursor++; 1760 final int GET_UNBOX_RESULT = nameCursor++; 1761 final int BOXED_ARGS = nameCursor++; 1762 final int LOOP = nameCursor++; 1763 final int UNBOX_RESULT = nameCursor++; 1764 1765 LambdaForm lform = basicType.form().cachedLambdaForm(MethodTypeForm.LF_LOOP); 1766 if (lform == null) { 1767 Name[] names = invokeArguments(nameCursor - ARG_LIMIT, basicType); 1768 1769 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLL(); 1770 names[THIS_MH] = names[THIS_MH].withConstraint(data); 1771 names[GET_CLAUSE_DATA] = new Name(data.getterFunction(0), names[THIS_MH]); 1772 names[GET_COLLECT_ARGS] = new Name(data.getterFunction(1), names[THIS_MH]); 1773 names[GET_UNBOX_RESULT] = new Name(data.getterFunction(2), names[THIS_MH]); 1774 1775 // t_{i}:L=MethodHandle.invokeBasic(collectArgs:L,a1:L,...); 1776 MethodType collectArgsType = basicType.changeReturnType(Object.class); 1777 MethodHandle invokeBasic = MethodHandles.basicInvoker(collectArgsType); 1778 Object[] args = new Object[invokeBasic.type().parameterCount()]; 1779 args[0] = names[GET_COLLECT_ARGS]; 1780 System.arraycopy(names, ARG_BASE, args, 1, ARG_LIMIT - ARG_BASE); 1781 names[BOXED_ARGS] = new Name(new NamedFunction(makeIntrinsic(invokeBasic, Intrinsic.LOOP)), args); 1782 1783 // t_{i+1}:L=MethodHandleImpl.loop(localTypes:L,clauses:L,t_{i}:L); 1784 Object[] lArgs = 1785 new Object[]{null, // placeholder for BasicType[] localTypes - will be added by LambdaFormEditor 1786 names[GET_CLAUSE_DATA], names[BOXED_ARGS]}; 1787 names[LOOP] = new Name(getFunction(NF_loop), lArgs); 1788 1789 // t_{i+2}:I=MethodHandle.invokeBasic(unbox:L,t_{i+1}:L); 1790 MethodHandle invokeBasicUnbox = MethodHandles.basicInvoker(MethodType.methodType(basicType.rtype(), Object.class)); 1791 Object[] unboxArgs = new Object[]{names[GET_UNBOX_RESULT], names[LOOP]}; 1792 names[UNBOX_RESULT] = new Name(invokeBasicUnbox, unboxArgs); 1793 1794 lform = basicType.form().setCachedLambdaForm(MethodTypeForm.LF_LOOP, 1795 LambdaForm.create(basicType.parameterCount() + 1, names, Kind.LOOP)); 1796 } 1797 1798 // BOXED_ARGS is the index into the names array where the loop idiom starts 1799 return lform.editor().noteLoopLocalTypesForm(BOXED_ARGS, localVarTypes); 1800 } 1801 1802 @AOTSafeClassInitializer 1803 static class LoopClauses { 1804 @Stable final MethodHandle[][] clauses; 1805 LoopClauses(MethodHandle[][] clauses) { 1806 assert clauses.length == 4; 1807 this.clauses = clauses; 1808 } 1809 @Override 1810 public String toString() { 1811 StringBuilder sb = new StringBuilder("LoopClauses -- "); 1812 for (int i = 0; i < 4; ++i) { 1813 if (i > 0) { 1814 sb.append(" "); 1815 } 1816 sb.append('<').append(i).append(">: "); 1817 MethodHandle[] hs = clauses[i]; 1818 for (int j = 0; j < hs.length; ++j) { 1819 if (j > 0) { 1820 sb.append(" "); 1821 } 1822 sb.append('*').append(j).append(": ").append(hs[j]).append('\n'); 1823 } 1824 } 1825 sb.append(" --\n"); 1826 return sb.toString(); 1827 } 1828 } 1829 1830 /** 1831 * Intrinsified during LambdaForm compilation 1832 * (see {@link InvokerBytecodeGenerator#emitLoop(int)}). 1833 */ 1834 @Hidden 1835 static Object loop(BasicType[] localTypes, LoopClauses clauseData, Object... av) throws Throwable { 1836 final MethodHandle[] init = clauseData.clauses[0]; 1837 final MethodHandle[] step = clauseData.clauses[1]; 1838 final MethodHandle[] pred = clauseData.clauses[2]; 1839 final MethodHandle[] fini = clauseData.clauses[3]; 1840 int varSize = (int) Stream.of(init).filter(h -> h.type().returnType() != void.class).count(); 1841 int nArgs = init[0].type().parameterCount(); 1842 Object[] varsAndArgs = new Object[varSize + nArgs]; 1843 for (int i = 0, v = 0; i < init.length; ++i) { 1844 MethodHandle ih = init[i]; 1845 if (ih.type().returnType() == void.class) { 1846 ih.invokeWithArguments(av); 1847 } else { 1848 varsAndArgs[v++] = ih.invokeWithArguments(av); 1849 } 1850 } 1851 System.arraycopy(av, 0, varsAndArgs, varSize, nArgs); 1852 final int nSteps = step.length; 1853 for (; ; ) { 1854 for (int i = 0, v = 0; i < nSteps; ++i) { 1855 MethodHandle p = pred[i]; 1856 MethodHandle s = step[i]; 1857 MethodHandle f = fini[i]; 1858 if (s.type().returnType() == void.class) { 1859 s.invokeWithArguments(varsAndArgs); 1860 } else { 1861 varsAndArgs[v++] = s.invokeWithArguments(varsAndArgs); 1862 } 1863 if (!(boolean) p.invokeWithArguments(varsAndArgs)) { 1864 return f.invokeWithArguments(varsAndArgs); 1865 } 1866 } 1867 } 1868 } 1869 1870 /** 1871 * This method is bound as the predicate in {@linkplain MethodHandles#countedLoop(MethodHandle, MethodHandle, 1872 * MethodHandle) counting loops}. 1873 * 1874 * @param limit the upper bound of the parameter, statically bound at loop creation time. 1875 * @param counter the counter parameter, passed in during loop execution. 1876 * 1877 * @return whether the counter has reached the limit. 1878 */ 1879 static boolean countedLoopPredicate(int limit, int counter) { 1880 return counter < limit; 1881 } 1882 1883 /** 1884 * This method is bound as the step function in {@linkplain MethodHandles#countedLoop(MethodHandle, MethodHandle, 1885 * MethodHandle) counting loops} to increment the counter. 1886 * 1887 * @param limit the upper bound of the loop counter (ignored). 1888 * @param counter the loop counter. 1889 * 1890 * @return the loop counter incremented by 1. 1891 */ 1892 static int countedLoopStep(int limit, int counter) { 1893 return counter + 1; 1894 } 1895 1896 /** 1897 * This is bound to initialize the loop-local iterator in {@linkplain MethodHandles#iteratedLoop iterating loops}. 1898 * 1899 * @param it the {@link Iterable} over which the loop iterates. 1900 * 1901 * @return an {@link Iterator} over the argument's elements. 1902 */ 1903 static Iterator<?> initIterator(Iterable<?> it) { 1904 return it.iterator(); 1905 } 1906 1907 /** 1908 * This method is bound as the predicate in {@linkplain MethodHandles#iteratedLoop iterating loops}. 1909 * 1910 * @param it the iterator to be checked. 1911 * 1912 * @return {@code true} iff there are more elements to iterate over. 1913 */ 1914 static boolean iteratePredicate(Iterator<?> it) { 1915 return it.hasNext(); 1916 } 1917 1918 /** 1919 * This method is bound as the step for retrieving the current value from the iterator in {@linkplain 1920 * MethodHandles#iteratedLoop iterating loops}. 1921 * 1922 * @param it the iterator. 1923 * 1924 * @return the next element from the iterator. 1925 */ 1926 static Object iterateNext(Iterator<?> it) { 1927 return it.next(); 1928 } 1929 1930 /** 1931 * Makes a {@code try-finally} handle that conforms to the type constraints. 1932 * 1933 * @param target the target to execute in a {@code try-finally} block. 1934 * @param cleanup the cleanup to execute in the {@code finally} block. 1935 * @param rtype the result type of the entire construct. 1936 * @param argTypes the types of the arguments. 1937 * 1938 * @return a handle on the constructed {@code try-finally} block. 1939 */ 1940 static MethodHandle makeTryFinally(MethodHandle target, MethodHandle cleanup, Class<?> rtype, Class<?>[] argTypes) { 1941 MethodType type = MethodType.methodType(rtype, argTypes); 1942 LambdaForm form = makeTryFinallyForm(type.basicType()); 1943 1944 // Prepare auxiliary method handles used during LambdaForm interpretation. 1945 // Box arguments and wrap them into Object[]: ValueConversions.array(). 1946 MethodType varargsType = type.changeReturnType(Object[].class); 1947 MethodHandle collectArgs = varargsArray(type.parameterCount()).asType(varargsType); 1948 MethodHandle unboxResult = unboxResultHandle(rtype); 1949 1950 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLLL(); 1951 BoundMethodHandle mh; 1952 try { 1953 mh = (BoundMethodHandle) data.factory().invokeBasic(type, form, (Object) target, (Object) cleanup, 1954 (Object) collectArgs, (Object) unboxResult); 1955 } catch (Throwable ex) { 1956 throw uncaughtException(ex); 1957 } 1958 assert(mh.type() == type); 1959 return mh; 1960 } 1961 1962 /** 1963 * The LambdaForm shape for the tryFinally combinator is as follows (assuming one reference parameter passed in 1964 * {@code a1}, and a reference return type, with the return value represented by {@code t8}): 1965 * <blockquote><pre>{@code 1966 * tryFinally=Lambda(a0:L,a1:L)=>{ 1967 * t2:L=BoundMethodHandle$Species_LLLL.argL0(a0:L); // target method handle 1968 * t3:L=BoundMethodHandle$Species_LLLL.argL1(a0:L); // cleanup method handle 1969 * t4:L=BoundMethodHandle$Species_LLLL.argL2(a0:L); // helper handle to box the arguments into an Object[] 1970 * t5:L=BoundMethodHandle$Species_LLLL.argL3(a0:L); // helper handle to unbox the result 1971 * t6:L=MethodHandle.invokeBasic(t4:L,a1:L); // box the arguments into an Object[] 1972 * t7:L=MethodHandleImpl.tryFinally(t2:L,t3:L,t6:L); // call the tryFinally executor 1973 * t8:L=MethodHandle.invokeBasic(t5:L,t7:L);t8:L} // unbox the result; return the result 1974 * }</pre></blockquote> 1975 * <p> 1976 * {@code argL0} and {@code argL1} are the target and cleanup method handles. 1977 * {@code argL2} and {@code argL3} are auxiliary method handles: {@code argL2} boxes arguments and wraps them into 1978 * {@code Object[]} ({@code ValueConversions.array()}), and {@code argL3} unboxes the result if necessary 1979 * ({@code ValueConversions.unbox()}). 1980 * <p> 1981 * Having {@code t4} and {@code t5} passed in via a BMH and not hardcoded in the lambda form allows to share lambda 1982 * forms among tryFinally combinators with the same basic type. 1983 */ 1984 private static LambdaForm makeTryFinallyForm(MethodType basicType) { 1985 LambdaForm lform = basicType.form().cachedLambdaForm(MethodTypeForm.LF_TF); 1986 if (lform != null) { 1987 return lform; 1988 } 1989 final int THIS_MH = 0; // the BMH_LLLL 1990 final int ARG_BASE = 1; // start of incoming arguments 1991 final int ARG_LIMIT = ARG_BASE + basicType.parameterCount(); 1992 1993 int nameCursor = ARG_LIMIT; 1994 final int GET_TARGET = nameCursor++; 1995 final int GET_CLEANUP = nameCursor++; 1996 final int GET_COLLECT_ARGS = nameCursor++; 1997 final int GET_UNBOX_RESULT = nameCursor++; 1998 final int BOXED_ARGS = nameCursor++; 1999 final int TRY_FINALLY = nameCursor++; 2000 final int UNBOX_RESULT = nameCursor++; 2001 2002 Name[] names = invokeArguments(nameCursor - ARG_LIMIT, basicType); 2003 2004 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLLL(); 2005 names[THIS_MH] = names[THIS_MH].withConstraint(data); 2006 names[GET_TARGET] = new Name(data.getterFunction(0), names[THIS_MH]); 2007 names[GET_CLEANUP] = new Name(data.getterFunction(1), names[THIS_MH]); 2008 names[GET_COLLECT_ARGS] = new Name(data.getterFunction(2), names[THIS_MH]); 2009 names[GET_UNBOX_RESULT] = new Name(data.getterFunction(3), names[THIS_MH]); 2010 2011 // t_{i}:L=MethodHandle.invokeBasic(collectArgs:L,a1:L,...); 2012 MethodType collectArgsType = basicType.changeReturnType(Object.class); 2013 MethodHandle invokeBasic = MethodHandles.basicInvoker(collectArgsType); 2014 Object[] args = new Object[invokeBasic.type().parameterCount()]; 2015 args[0] = names[GET_COLLECT_ARGS]; 2016 System.arraycopy(names, ARG_BASE, args, 1, ARG_LIMIT-ARG_BASE); 2017 names[BOXED_ARGS] = new Name(new NamedFunction(makeIntrinsic(invokeBasic, Intrinsic.TRY_FINALLY)), args); 2018 2019 // t_{i+1}:L=MethodHandleImpl.tryFinally(target:L,exType:L,catcher:L,t_{i}:L); 2020 Object[] tfArgs = new Object[] {names[GET_TARGET], names[GET_CLEANUP], names[BOXED_ARGS]}; 2021 names[TRY_FINALLY] = new Name(getFunction(NF_tryFinally), tfArgs); 2022 2023 // t_{i+2}:I=MethodHandle.invokeBasic(unbox:L,t_{i+1}:L); 2024 MethodHandle invokeBasicUnbox = MethodHandles.basicInvoker(MethodType.methodType(basicType.rtype(), Object.class)); 2025 Object[] unboxArgs = new Object[] {names[GET_UNBOX_RESULT], names[TRY_FINALLY]}; 2026 names[UNBOX_RESULT] = new Name(invokeBasicUnbox, unboxArgs); 2027 2028 lform = LambdaForm.create(basicType.parameterCount() + 1, names, Kind.TRY_FINALLY); 2029 2030 return basicType.form().setCachedLambdaForm(MethodTypeForm.LF_TF, lform); 2031 } 2032 2033 /** 2034 * Intrinsified during LambdaForm compilation 2035 * (see {@link InvokerBytecodeGenerator#emitTryFinally emitTryFinally}). 2036 */ 2037 @Hidden 2038 static Object tryFinally(MethodHandle target, MethodHandle cleanup, Object... av) throws Throwable { 2039 Throwable t = null; 2040 Object r = null; 2041 try { 2042 r = target.invokeWithArguments(av); 2043 } catch (Throwable thrown) { 2044 t = thrown; 2045 throw t; 2046 } finally { 2047 Object[] args = target.type().returnType() == void.class ? prepend(av, t) : prepend(av, t, r); 2048 r = cleanup.invokeWithArguments(args); 2049 } 2050 return r; 2051 } 2052 2053 // see varargsArray method for chaching/package-private version of this 2054 private static MethodHandle makeCollector(Class<?> arrayType, int parameterCount) { 2055 MethodType type = MethodType.methodType(arrayType, Collections.nCopies(parameterCount, arrayType.componentType())); 2056 MethodHandle newArray = MethodHandles.arrayConstructor(arrayType); 2057 2058 LambdaForm form = makeCollectorForm(type.basicType(), arrayType); 2059 2060 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_L(); 2061 BoundMethodHandle mh; 2062 try { 2063 mh = (BoundMethodHandle) data.factory().invokeBasic(type, form, (Object) newArray); 2064 } catch (Throwable ex) { 2065 throw uncaughtException(ex); 2066 } 2067 assert(mh.type() == type); 2068 return mh; 2069 } 2070 2071 private static LambdaForm makeCollectorForm(MethodType basicType, Class<?> arrayType) { 2072 int parameterCount = basicType.parameterCount(); 2073 2074 // Only share the lambda form for empty arrays and reference types. 2075 // Sharing based on the basic type alone doesn't work because 2076 // we need a separate lambda form for byte/short/char/int which 2077 // are all erased to int otherwise. 2078 // Other caching for primitive types happens at the MethodHandle level (see varargsArray). 2079 boolean isReferenceType = !arrayType.componentType().isPrimitive(); 2080 boolean isSharedLambdaForm = parameterCount == 0 || isReferenceType; 2081 if (isSharedLambdaForm) { 2082 LambdaForm lform = basicType.form().cachedLambdaForm(MethodTypeForm.LF_COLLECTOR); 2083 if (lform != null) { 2084 return lform; 2085 } 2086 } 2087 2088 // use erased accessor for reference types 2089 MethodHandle storeFunc = isReferenceType 2090 ? ArrayAccessor.OBJECT_ARRAY_SETTER 2091 : makeArrayElementAccessor(arrayType, ArrayAccess.SET); 2092 2093 final int THIS_MH = 0; // the BMH_L 2094 final int ARG_BASE = 1; // start of incoming arguments 2095 final int ARG_LIMIT = ARG_BASE + parameterCount; 2096 2097 int nameCursor = ARG_LIMIT; 2098 final int GET_NEW_ARRAY = nameCursor++; 2099 final int CALL_NEW_ARRAY = nameCursor++; 2100 final int STORE_ELEMENT_BASE = nameCursor; 2101 final int STORE_ELEMENT_LIMIT = STORE_ELEMENT_BASE + parameterCount; 2102 nameCursor = STORE_ELEMENT_LIMIT; 2103 2104 Name[] names = invokeArguments(nameCursor - ARG_LIMIT, basicType); 2105 2106 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_L(); 2107 names[THIS_MH] = names[THIS_MH].withConstraint(data); 2108 names[GET_NEW_ARRAY] = new Name(data.getterFunction(0), names[THIS_MH]); 2109 2110 MethodHandle invokeBasic = MethodHandles.basicInvoker(MethodType.methodType(Object.class, int.class)); 2111 names[CALL_NEW_ARRAY] = new Name(new NamedFunction(invokeBasic), names[GET_NEW_ARRAY], parameterCount); 2112 for (int storeIndex = 0, 2113 storeNameCursor = STORE_ELEMENT_BASE, 2114 argCursor = ARG_BASE; 2115 storeNameCursor < STORE_ELEMENT_LIMIT; 2116 storeIndex++, storeNameCursor++, argCursor++){ 2117 2118 names[storeNameCursor] = new Name(new NamedFunction(makeIntrinsic(storeFunc, Intrinsic.ARRAY_STORE)), 2119 names[CALL_NEW_ARRAY], storeIndex, names[argCursor]); 2120 } 2121 2122 LambdaForm lform = LambdaForm.create(basicType.parameterCount() + 1, names, CALL_NEW_ARRAY, Kind.COLLECTOR); 2123 if (isSharedLambdaForm) { 2124 lform = basicType.form().setCachedLambdaForm(MethodTypeForm.LF_COLLECTOR, lform); 2125 } 2126 return lform; 2127 } 2128 2129 // use a wrapper because we need this array to be @Stable 2130 @AOTSafeClassInitializer 2131 static class CasesHolder { 2132 @Stable 2133 final MethodHandle[] cases; 2134 2135 public CasesHolder(MethodHandle[] cases) { 2136 this.cases = cases; 2137 } 2138 } 2139 2140 static MethodHandle makeTableSwitch(MethodType type, MethodHandle defaultCase, MethodHandle[] caseActions) { 2141 MethodType varargsType = type.changeReturnType(Object[].class); 2142 MethodHandle collectArgs = varargsArray(type.parameterCount()).asType(varargsType); 2143 2144 MethodHandle unboxResult = unboxResultHandle(type.returnType()); 2145 2146 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLLL(); 2147 LambdaForm form = makeTableSwitchForm(type.basicType(), data, caseActions.length); 2148 BoundMethodHandle mh; 2149 CasesHolder caseHolder = new CasesHolder(caseActions); 2150 try { 2151 mh = (BoundMethodHandle) data.factory().invokeBasic(type, form, (Object) defaultCase, (Object) collectArgs, 2152 (Object) unboxResult, (Object) caseHolder); 2153 } catch (Throwable ex) { 2154 throw uncaughtException(ex); 2155 } 2156 assert(mh.type() == type); 2157 return mh; 2158 } 2159 2160 @AOTSafeClassInitializer 2161 private static class TableSwitchCacheKey { 2162 private static final Map<TableSwitchCacheKey, LambdaForm> CACHE = new ConcurrentHashMap<>(); 2163 2164 private final MethodType basicType; 2165 private final int numberOfCases; 2166 2167 public TableSwitchCacheKey(MethodType basicType, int numberOfCases) { 2168 this.basicType = basicType; 2169 this.numberOfCases = numberOfCases; 2170 } 2171 2172 @Override 2173 public boolean equals(Object o) { 2174 if (this == o) return true; 2175 if (o == null || getClass() != o.getClass()) return false; 2176 TableSwitchCacheKey that = (TableSwitchCacheKey) o; 2177 return numberOfCases == that.numberOfCases && Objects.equals(basicType, that.basicType); 2178 } 2179 @Override 2180 public int hashCode() { 2181 return Objects.hash(basicType, numberOfCases); 2182 } 2183 } 2184 2185 private static LambdaForm makeTableSwitchForm(MethodType basicType, BoundMethodHandle.SpeciesData data, 2186 int numCases) { 2187 // We need to cache based on the basic type X number of cases, 2188 // since the number of cases is used when generating bytecode. 2189 // This also means that we can't use the cache in MethodTypeForm, 2190 // which only uses the basic type as a key. 2191 TableSwitchCacheKey key = new TableSwitchCacheKey(basicType, numCases); 2192 LambdaForm lform = TableSwitchCacheKey.CACHE.get(key); 2193 if (lform != null) { 2194 return lform; 2195 } 2196 2197 final int THIS_MH = 0; 2198 final int ARG_BASE = 1; // start of incoming arguments 2199 final int ARG_LIMIT = ARG_BASE + basicType.parameterCount(); 2200 final int ARG_SWITCH_ON = ARG_BASE; 2201 assert ARG_SWITCH_ON < ARG_LIMIT; 2202 2203 int nameCursor = ARG_LIMIT; 2204 final int GET_COLLECT_ARGS = nameCursor++; 2205 final int GET_DEFAULT_CASE = nameCursor++; 2206 final int GET_UNBOX_RESULT = nameCursor++; 2207 final int GET_CASES = nameCursor++; 2208 final int BOXED_ARGS = nameCursor++; 2209 final int TABLE_SWITCH = nameCursor++; 2210 final int UNBOXED_RESULT = nameCursor++; 2211 2212 int fieldCursor = 0; 2213 final int FIELD_DEFAULT_CASE = fieldCursor++; 2214 final int FIELD_COLLECT_ARGS = fieldCursor++; 2215 final int FIELD_UNBOX_RESULT = fieldCursor++; 2216 final int FIELD_CASES = fieldCursor++; 2217 2218 Name[] names = invokeArguments(nameCursor - ARG_LIMIT, basicType); 2219 2220 names[THIS_MH] = names[THIS_MH].withConstraint(data); 2221 names[GET_DEFAULT_CASE] = new Name(data.getterFunction(FIELD_DEFAULT_CASE), names[THIS_MH]); 2222 names[GET_COLLECT_ARGS] = new Name(data.getterFunction(FIELD_COLLECT_ARGS), names[THIS_MH]); 2223 names[GET_UNBOX_RESULT] = new Name(data.getterFunction(FIELD_UNBOX_RESULT), names[THIS_MH]); 2224 names[GET_CASES] = new Name(data.getterFunction(FIELD_CASES), names[THIS_MH]); 2225 2226 { 2227 MethodType collectArgsType = basicType.changeReturnType(Object.class); 2228 MethodHandle invokeBasic = MethodHandles.basicInvoker(collectArgsType); 2229 Object[] args = new Object[invokeBasic.type().parameterCount()]; 2230 args[0] = names[GET_COLLECT_ARGS]; 2231 System.arraycopy(names, ARG_BASE, args, 1, ARG_LIMIT - ARG_BASE); 2232 names[BOXED_ARGS] = new Name(new NamedFunction(makeIntrinsic(invokeBasic, Intrinsic.TABLE_SWITCH, numCases)), args); 2233 } 2234 2235 { 2236 Object[] tfArgs = new Object[]{ 2237 names[ARG_SWITCH_ON], names[GET_DEFAULT_CASE], names[GET_CASES], names[BOXED_ARGS]}; 2238 names[TABLE_SWITCH] = new Name(getFunction(NF_tableSwitch), tfArgs); 2239 } 2240 2241 { 2242 MethodHandle invokeBasic = MethodHandles.basicInvoker(MethodType.methodType(basicType.rtype(), Object.class)); 2243 Object[] unboxArgs = new Object[]{names[GET_UNBOX_RESULT], names[TABLE_SWITCH]}; 2244 names[UNBOXED_RESULT] = new Name(invokeBasic, unboxArgs); 2245 } 2246 2247 lform = LambdaForm.create(basicType.parameterCount() + 1, names, Kind.TABLE_SWITCH); 2248 LambdaForm prev = TableSwitchCacheKey.CACHE.putIfAbsent(key, lform); 2249 return prev != null ? prev : lform; 2250 } 2251 2252 @Hidden 2253 static Object tableSwitch(int input, MethodHandle defaultCase, CasesHolder holder, Object[] args) throws Throwable { 2254 MethodHandle[] caseActions = holder.cases; 2255 MethodHandle selectedCase; 2256 if (input < 0 || input >= caseActions.length) { 2257 selectedCase = defaultCase; 2258 } else { 2259 selectedCase = caseActions[input]; 2260 } 2261 return selectedCase.invokeWithArguments(args); 2262 } 2263 2264 // type is validated, value is not 2265 static MethodHandle makeConstantReturning(Class<?> type, Object value) { 2266 var callType = MethodType.methodType(type); 2267 var basicType = BasicType.basicType(type); 2268 var form = constantForm(basicType); 2269 2270 if (type.isPrimitive()) { 2271 assert type != void.class; 2272 var wrapper = Wrapper.forPrimitiveType(type); 2273 var v = wrapper.convert(value, type); // throws CCE 2274 return switch (wrapper) { 2275 case INT -> BoundMethodHandle.bindSingleI(callType, form, (int) v); 2276 case LONG -> BoundMethodHandle.bindSingleJ(callType, form, (long) v); 2277 case FLOAT -> BoundMethodHandle.bindSingleF(callType, form, (float) v); 2278 case DOUBLE -> BoundMethodHandle.bindSingleD(callType, form, (double) v); 2279 default -> BoundMethodHandle.bindSingleI(callType, form, ValueConversions.widenSubword(v)); 2280 }; 2281 } 2282 2283 var v = type.cast(value); // throws CCE 2284 return BoundMethodHandle.bindSingleL(callType, form, v); 2285 } 2286 2287 // Indexes into constant method handles: 2288 static final int 2289 MH_cast = 0, 2290 MH_selectAlternative = 1, 2291 MH_countedLoopPred = 2, 2292 MH_countedLoopStep = 3, 2293 MH_initIterator = 4, 2294 MH_iteratePred = 5, 2295 MH_iterateNext = 6, 2296 MH_Array_newInstance = 7, 2297 MH_VarHandles_handleCheckedExceptions = 8, 2298 MH_LIMIT = 9; 2299 2300 static MethodHandle getConstantHandle(int idx) { 2301 MethodHandle handle = HANDLES[idx]; 2302 if (handle != null) { 2303 return handle; 2304 } 2305 return setCachedHandle(idx, makeConstantHandle(idx)); 2306 } 2307 2308 private static synchronized MethodHandle setCachedHandle(int idx, final MethodHandle method) { 2309 // Simulate a CAS, to avoid racy duplication of results. 2310 MethodHandle prev = HANDLES[idx]; 2311 if (prev != null) { 2312 return prev; 2313 } 2314 HANDLES[idx] = method; 2315 return method; 2316 } 2317 2318 // Local constant method handles: 2319 private static final @Stable MethodHandle[] HANDLES = new MethodHandle[MH_LIMIT]; 2320 2321 private static MethodHandle makeConstantHandle(int idx) { 2322 try { 2323 switch (idx) { 2324 case MH_cast: 2325 return IMPL_LOOKUP.findVirtual(Class.class, "cast", 2326 MethodType.methodType(Object.class, Object.class)); 2327 case MH_selectAlternative: 2328 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "selectAlternative", 2329 MethodType.methodType(MethodHandle.class, boolean.class, MethodHandle.class, MethodHandle.class)); 2330 case MH_countedLoopPred: 2331 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "countedLoopPredicate", 2332 MethodType.methodType(boolean.class, int.class, int.class)); 2333 case MH_countedLoopStep: 2334 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "countedLoopStep", 2335 MethodType.methodType(int.class, int.class, int.class)); 2336 case MH_initIterator: 2337 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "initIterator", 2338 MethodType.methodType(Iterator.class, Iterable.class)); 2339 case MH_iteratePred: 2340 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "iteratePredicate", 2341 MethodType.methodType(boolean.class, Iterator.class)); 2342 case MH_iterateNext: 2343 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "iterateNext", 2344 MethodType.methodType(Object.class, Iterator.class)); 2345 case MH_Array_newInstance: 2346 return IMPL_LOOKUP.findStatic(Array.class, "newInstance", 2347 MethodType.methodType(Object.class, Class.class, int.class)); 2348 case MH_VarHandles_handleCheckedExceptions: 2349 return IMPL_LOOKUP.findStatic(VarHandles.class, "handleCheckedExceptions", 2350 MethodType.methodType(void.class, Throwable.class)); 2351 } 2352 } catch (ReflectiveOperationException ex) { 2353 throw newInternalError(ex); 2354 } 2355 throw newInternalError("Unknown function index: " + idx); 2356 } 2357 }