1 /* 2 * Copyright (c) 2008, 2015, 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 java.security.AccessController; 29 import java.security.PrivilegedAction; 30 import java.util.ArrayList; 31 import java.util.Arrays; 32 import java.util.Collections; 33 import java.util.function.Function; 34 35 import sun.invoke.empty.Empty; 36 import sun.invoke.util.ValueConversions; 37 import sun.invoke.util.VerifyType; 38 import sun.invoke.util.Wrapper; 39 import jdk.internal.HotSpotIntrinsicCandidate; 40 import sun.reflect.CallerSensitive; 41 import sun.reflect.Reflection; 42 import static java.lang.invoke.LambdaForm.*; 43 import static java.lang.invoke.MethodHandleStatics.*; 44 import static java.lang.invoke.MethodHandles.Lookup.IMPL_LOOKUP; 45 46 /** 47 * Trusted implementation code for MethodHandle. 48 * @author jrose 49 */ 50 /*non-public*/ abstract class MethodHandleImpl { 51 // Do not adjust this except for special platforms: 52 private static final int MAX_ARITY; 53 static { 54 final Object[] values = { 255 }; 55 AccessController.doPrivileged(new PrivilegedAction<>() { 56 @Override 57 public Void run() { 58 values[0] = Integer.getInteger(MethodHandleImpl.class.getName()+".MAX_ARITY", 255); 59 return null; 60 } 61 }); 62 MAX_ARITY = (Integer) values[0]; 63 } 64 65 /// Factory methods to create method handles: 66 67 static void initStatics() { 68 // Trigger selected static initializations. 69 MemberName.Factory.INSTANCE.getClass(); 70 } 71 72 static MethodHandle makeArrayElementAccessor(Class<?> arrayClass, boolean isSetter) { 73 if (arrayClass == Object[].class) 74 return (isSetter ? ArrayAccessor.OBJECT_ARRAY_SETTER : ArrayAccessor.OBJECT_ARRAY_GETTER); 75 if (!arrayClass.isArray()) 76 throw newIllegalArgumentException("not an array: "+arrayClass); 77 MethodHandle[] cache = ArrayAccessor.TYPED_ACCESSORS.get(arrayClass); 78 int cacheIndex = (isSetter ? ArrayAccessor.SETTER_INDEX : ArrayAccessor.GETTER_INDEX); 79 MethodHandle mh = cache[cacheIndex]; 80 if (mh != null) return mh; 81 mh = ArrayAccessor.getAccessor(arrayClass, isSetter); 82 MethodType correctType = ArrayAccessor.correctType(arrayClass, isSetter); 83 if (mh.type() != correctType) { 84 assert(mh.type().parameterType(0) == Object[].class); 85 assert((isSetter ? mh.type().parameterType(2) : mh.type().returnType()) == Object.class); 86 assert(isSetter || correctType.parameterType(0).getComponentType() == correctType.returnType()); 87 // safe to view non-strictly, because element type follows from array type 88 mh = mh.viewAsType(correctType, false); 89 } 90 mh = makeIntrinsic(mh, (isSetter ? Intrinsic.ARRAY_STORE : Intrinsic.ARRAY_LOAD)); 91 // Atomically update accessor cache. 92 synchronized(cache) { 93 if (cache[cacheIndex] == null) { 94 cache[cacheIndex] = mh; 95 } else { 96 // Throw away newly constructed accessor and use cached version. 97 mh = cache[cacheIndex]; 98 } 99 } 100 return mh; 101 } 102 103 static final class ArrayAccessor { 104 /// Support for array element access 105 static final int GETTER_INDEX = 0, SETTER_INDEX = 1, INDEX_LIMIT = 2; 106 static final ClassValue<MethodHandle[]> TYPED_ACCESSORS 107 = new ClassValue<MethodHandle[]>() { 108 @Override 109 protected MethodHandle[] computeValue(Class<?> type) { 110 return new MethodHandle[INDEX_LIMIT]; 111 } 112 }; 113 static final MethodHandle OBJECT_ARRAY_GETTER, OBJECT_ARRAY_SETTER; 114 static { 115 MethodHandle[] cache = TYPED_ACCESSORS.get(Object[].class); 116 cache[GETTER_INDEX] = OBJECT_ARRAY_GETTER = makeIntrinsic(getAccessor(Object[].class, false), Intrinsic.ARRAY_LOAD); 117 cache[SETTER_INDEX] = OBJECT_ARRAY_SETTER = makeIntrinsic(getAccessor(Object[].class, true), Intrinsic.ARRAY_STORE); 118 119 assert(InvokerBytecodeGenerator.isStaticallyInvocable(ArrayAccessor.OBJECT_ARRAY_GETTER.internalMemberName())); 120 assert(InvokerBytecodeGenerator.isStaticallyInvocable(ArrayAccessor.OBJECT_ARRAY_SETTER.internalMemberName())); 121 } 122 123 static int getElementI(int[] a, int i) { return a[i]; } 124 static long getElementJ(long[] a, int i) { return a[i]; } 125 static float getElementF(float[] a, int i) { return a[i]; } 126 static double getElementD(double[] a, int i) { return a[i]; } 127 static boolean getElementZ(boolean[] a, int i) { return a[i]; } 128 static byte getElementB(byte[] a, int i) { return a[i]; } 129 static short getElementS(short[] a, int i) { return a[i]; } 130 static char getElementC(char[] a, int i) { return a[i]; } 131 static Object getElementL(Object[] a, int i) { return a[i]; } 132 133 static void setElementI(int[] a, int i, int x) { a[i] = x; } 134 static void setElementJ(long[] a, int i, long x) { a[i] = x; } 135 static void setElementF(float[] a, int i, float x) { a[i] = x; } 136 static void setElementD(double[] a, int i, double x) { a[i] = x; } 137 static void setElementZ(boolean[] a, int i, boolean x) { a[i] = x; } 138 static void setElementB(byte[] a, int i, byte x) { a[i] = x; } 139 static void setElementS(short[] a, int i, short x) { a[i] = x; } 140 static void setElementC(char[] a, int i, char x) { a[i] = x; } 141 static void setElementL(Object[] a, int i, Object x) { a[i] = x; } 142 143 static String name(Class<?> arrayClass, boolean isSetter) { 144 Class<?> elemClass = arrayClass.getComponentType(); 145 if (elemClass == null) throw newIllegalArgumentException("not an array", arrayClass); 146 return (!isSetter ? "getElement" : "setElement") + Wrapper.basicTypeChar(elemClass); 147 } 148 static MethodType type(Class<?> arrayClass, boolean isSetter) { 149 Class<?> elemClass = arrayClass.getComponentType(); 150 Class<?> arrayArgClass = arrayClass; 151 if (!elemClass.isPrimitive()) { 152 arrayArgClass = Object[].class; 153 elemClass = Object.class; 154 } 155 return !isSetter ? 156 MethodType.methodType(elemClass, arrayArgClass, int.class) : 157 MethodType.methodType(void.class, arrayArgClass, int.class, elemClass); 158 } 159 static MethodType correctType(Class<?> arrayClass, boolean isSetter) { 160 Class<?> elemClass = arrayClass.getComponentType(); 161 return !isSetter ? 162 MethodType.methodType(elemClass, arrayClass, int.class) : 163 MethodType.methodType(void.class, arrayClass, int.class, elemClass); 164 } 165 static MethodHandle getAccessor(Class<?> arrayClass, boolean isSetter) { 166 String name = name(arrayClass, isSetter); 167 MethodType type = type(arrayClass, isSetter); 168 try { 169 return IMPL_LOOKUP.findStatic(ArrayAccessor.class, name, type); 170 } catch (ReflectiveOperationException ex) { 171 throw uncaughtException(ex); 172 } 173 } 174 } 175 176 /** 177 * Create a JVM-level adapter method handle to conform the given method 178 * handle to the similar newType, using only pairwise argument conversions. 179 * For each argument, convert incoming argument to the exact type needed. 180 * The argument conversions allowed are casting, boxing and unboxing, 181 * integral widening or narrowing, and floating point widening or narrowing. 182 * @param srcType required call type 183 * @param target original method handle 184 * @param strict if true, only asType conversions are allowed; if false, explicitCastArguments conversions allowed 185 * @param monobox if true, unboxing conversions are assumed to be exactly typed (Integer to int only, not long or double) 186 * @return an adapter to the original handle with the desired new type, 187 * or the original target if the types are already identical 188 * or null if the adaptation cannot be made 189 */ 190 static MethodHandle makePairwiseConvert(MethodHandle target, MethodType srcType, 191 boolean strict, boolean monobox) { 192 MethodType dstType = target.type(); 193 if (srcType == dstType) 194 return target; 195 return makePairwiseConvertByEditor(target, srcType, strict, monobox); 196 } 197 198 private static int countNonNull(Object[] array) { 199 int count = 0; 200 for (Object x : array) { 201 if (x != null) ++count; 202 } 203 return count; 204 } 205 206 static MethodHandle makePairwiseConvertByEditor(MethodHandle target, MethodType srcType, 207 boolean strict, boolean monobox) { 208 Object[] convSpecs = computeValueConversions(srcType, target.type(), strict, monobox); 209 int convCount = countNonNull(convSpecs); 210 if (convCount == 0) 211 return target.viewAsType(srcType, strict); 212 MethodType basicSrcType = srcType.basicType(); 213 MethodType midType = target.type().basicType(); 214 BoundMethodHandle mh = target.rebind(); 215 // FIXME: Reduce number of bindings when there is more than one Class conversion. 216 // FIXME: Reduce number of bindings when there are repeated conversions. 217 for (int i = 0; i < convSpecs.length-1; i++) { 218 Object convSpec = convSpecs[i]; 219 if (convSpec == null) continue; 220 MethodHandle fn; 221 if (convSpec instanceof Class) { 222 fn = getConstantHandle(MH_cast).bindTo(convSpec); 223 } else { 224 fn = (MethodHandle) convSpec; 225 } 226 Class<?> newType = basicSrcType.parameterType(i); 227 if (--convCount == 0) 228 midType = srcType; 229 else 230 midType = midType.changeParameterType(i, newType); 231 LambdaForm form2 = mh.editor().filterArgumentForm(1+i, BasicType.basicType(newType)); 232 mh = mh.copyWithExtendL(midType, form2, fn); 233 mh = mh.rebind(); 234 } 235 Object convSpec = convSpecs[convSpecs.length-1]; 236 if (convSpec != null) { 237 MethodHandle fn; 238 if (convSpec instanceof Class) { 239 if (convSpec == void.class) 240 fn = null; 241 else 242 fn = getConstantHandle(MH_cast).bindTo(convSpec); 243 } else { 244 fn = (MethodHandle) convSpec; 245 } 246 Class<?> newType = basicSrcType.returnType(); 247 assert(--convCount == 0); 248 midType = srcType; 249 if (fn != null) { 250 mh = mh.rebind(); // rebind if too complex 251 LambdaForm form2 = mh.editor().filterReturnForm(BasicType.basicType(newType), false); 252 mh = mh.copyWithExtendL(midType, form2, fn); 253 } else { 254 LambdaForm form2 = mh.editor().filterReturnForm(BasicType.basicType(newType), true); 255 mh = mh.copyWith(midType, form2); 256 } 257 } 258 assert(convCount == 0); 259 assert(mh.type().equals(srcType)); 260 return mh; 261 } 262 263 static MethodHandle makePairwiseConvertIndirect(MethodHandle target, MethodType srcType, 264 boolean strict, boolean monobox) { 265 assert(target.type().parameterCount() == srcType.parameterCount()); 266 // Calculate extra arguments (temporaries) required in the names array. 267 Object[] convSpecs = computeValueConversions(srcType, target.type(), strict, monobox); 268 final int INARG_COUNT = srcType.parameterCount(); 269 int convCount = countNonNull(convSpecs); 270 boolean retConv = (convSpecs[INARG_COUNT] != null); 271 boolean retVoid = srcType.returnType() == void.class; 272 if (retConv && retVoid) { 273 convCount -= 1; 274 retConv = false; 275 } 276 277 final int IN_MH = 0; 278 final int INARG_BASE = 1; 279 final int INARG_LIMIT = INARG_BASE + INARG_COUNT; 280 final int NAME_LIMIT = INARG_LIMIT + convCount + 1; 281 final int RETURN_CONV = (!retConv ? -1 : NAME_LIMIT - 1); 282 final int OUT_CALL = (!retConv ? NAME_LIMIT : RETURN_CONV) - 1; 283 final int RESULT = (retVoid ? -1 : NAME_LIMIT - 1); 284 285 // Now build a LambdaForm. 286 MethodType lambdaType = srcType.basicType().invokerType(); 287 Name[] names = arguments(NAME_LIMIT - INARG_LIMIT, lambdaType); 288 289 // Collect the arguments to the outgoing call, maybe with conversions: 290 final int OUTARG_BASE = 0; // target MH is Name.function, name Name.arguments[0] 291 Object[] outArgs = new Object[OUTARG_BASE + INARG_COUNT]; 292 293 int nameCursor = INARG_LIMIT; 294 for (int i = 0; i < INARG_COUNT; i++) { 295 Object convSpec = convSpecs[i]; 296 if (convSpec == null) { 297 // do nothing: difference is trivial 298 outArgs[OUTARG_BASE + i] = names[INARG_BASE + i]; 299 continue; 300 } 301 302 Name conv; 303 if (convSpec instanceof Class) { 304 Class<?> convClass = (Class<?>) convSpec; 305 conv = new Name(getConstantHandle(MH_cast), convClass, names[INARG_BASE + i]); 306 } else { 307 MethodHandle fn = (MethodHandle) convSpec; 308 conv = new Name(fn, names[INARG_BASE + i]); 309 } 310 assert(names[nameCursor] == null); 311 names[nameCursor++] = conv; 312 assert(outArgs[OUTARG_BASE + i] == null); 313 outArgs[OUTARG_BASE + i] = conv; 314 } 315 316 // Build argument array for the call. 317 assert(nameCursor == OUT_CALL); 318 names[OUT_CALL] = new Name(target, outArgs); 319 320 Object convSpec = convSpecs[INARG_COUNT]; 321 if (!retConv) { 322 assert(OUT_CALL == names.length-1); 323 } else { 324 Name conv; 325 if (convSpec == void.class) { 326 conv = new Name(LambdaForm.constantZero(BasicType.basicType(srcType.returnType()))); 327 } else if (convSpec instanceof Class) { 328 Class<?> convClass = (Class<?>) convSpec; 329 conv = new Name(getConstantHandle(MH_cast), convClass, names[OUT_CALL]); 330 } else { 331 MethodHandle fn = (MethodHandle) convSpec; 332 if (fn.type().parameterCount() == 0) 333 conv = new Name(fn); // don't pass retval to void conversion 334 else 335 conv = new Name(fn, names[OUT_CALL]); 336 } 337 assert(names[RETURN_CONV] == null); 338 names[RETURN_CONV] = conv; 339 assert(RETURN_CONV == names.length-1); 340 } 341 342 LambdaForm form = new LambdaForm("convert", lambdaType.parameterCount(), names, RESULT); 343 return SimpleMethodHandle.make(srcType, form); 344 } 345 346 static Object[] computeValueConversions(MethodType srcType, MethodType dstType, 347 boolean strict, boolean monobox) { 348 final int INARG_COUNT = srcType.parameterCount(); 349 Object[] convSpecs = new Object[INARG_COUNT+1]; 350 for (int i = 0; i <= INARG_COUNT; i++) { 351 boolean isRet = (i == INARG_COUNT); 352 Class<?> src = isRet ? dstType.returnType() : srcType.parameterType(i); 353 Class<?> dst = isRet ? srcType.returnType() : dstType.parameterType(i); 354 if (!VerifyType.isNullConversion(src, dst, /*keepInterfaces=*/ strict)) { 355 convSpecs[i] = valueConversion(src, dst, strict, monobox); 356 } 357 } 358 return convSpecs; 359 } 360 static MethodHandle makePairwiseConvert(MethodHandle target, MethodType srcType, 361 boolean strict) { 362 return makePairwiseConvert(target, srcType, strict, /*monobox=*/ false); 363 } 364 365 /** 366 * Find a conversion function from the given source to the given destination. 367 * This conversion function will be used as a LF NamedFunction. 368 * Return a Class object if a simple cast is needed. 369 * Return void.class if void is involved. 370 */ 371 static Object valueConversion(Class<?> src, Class<?> dst, boolean strict, boolean monobox) { 372 assert(!VerifyType.isNullConversion(src, dst, /*keepInterfaces=*/ strict)); // caller responsibility 373 if (dst == void.class) 374 return dst; 375 MethodHandle fn; 376 if (src.isPrimitive()) { 377 if (src == void.class) { 378 return void.class; // caller must recognize this specially 379 } else if (dst.isPrimitive()) { 380 // Examples: int->byte, byte->int, boolean->int (!strict) 381 fn = ValueConversions.convertPrimitive(src, dst); 382 } else { 383 // Examples: int->Integer, boolean->Object, float->Number 384 Wrapper wsrc = Wrapper.forPrimitiveType(src); 385 fn = ValueConversions.boxExact(wsrc); 386 assert(fn.type().parameterType(0) == wsrc.primitiveType()); 387 assert(fn.type().returnType() == wsrc.wrapperType()); 388 if (!VerifyType.isNullConversion(wsrc.wrapperType(), dst, strict)) { 389 // Corner case, such as int->Long, which will probably fail. 390 MethodType mt = MethodType.methodType(dst, src); 391 if (strict) 392 fn = fn.asType(mt); 393 else 394 fn = MethodHandleImpl.makePairwiseConvert(fn, mt, /*strict=*/ false); 395 } 396 } 397 } else if (dst.isPrimitive()) { 398 Wrapper wdst = Wrapper.forPrimitiveType(dst); 399 if (monobox || src == wdst.wrapperType()) { 400 // Use a strongly-typed unboxer, if possible. 401 fn = ValueConversions.unboxExact(wdst, strict); 402 } else { 403 // Examples: Object->int, Number->int, Comparable->int, Byte->int 404 // must include additional conversions 405 // src must be examined at runtime, to detect Byte, Character, etc. 406 fn = (strict 407 ? ValueConversions.unboxWiden(wdst) 408 : ValueConversions.unboxCast(wdst)); 409 } 410 } else { 411 // Simple reference conversion. 412 // Note: Do not check for a class hierarchy relation 413 // between src and dst. In all cases a 'null' argument 414 // will pass the cast conversion. 415 return dst; 416 } 417 assert(fn.type().parameterCount() <= 1) : "pc"+Arrays.asList(src.getSimpleName(), dst.getSimpleName(), fn); 418 return fn; 419 } 420 421 static MethodHandle makeVarargsCollector(MethodHandle target, Class<?> arrayType) { 422 MethodType type = target.type(); 423 int last = type.parameterCount() - 1; 424 if (type.parameterType(last) != arrayType) 425 target = target.asType(type.changeParameterType(last, arrayType)); 426 target = target.asFixedArity(); // make sure this attribute is turned off 427 return new AsVarargsCollector(target, arrayType); 428 } 429 430 private static final class AsVarargsCollector extends DelegatingMethodHandle { 431 private final MethodHandle target; 432 private final Class<?> arrayType; 433 private @Stable MethodHandle asCollectorCache; 434 435 AsVarargsCollector(MethodHandle target, Class<?> arrayType) { 436 this(target.type(), target, arrayType); 437 } 438 AsVarargsCollector(MethodType type, MethodHandle target, Class<?> arrayType) { 439 super(type, target); 440 this.target = target; 441 this.arrayType = arrayType; 442 this.asCollectorCache = target.asCollector(arrayType, 0); 443 } 444 445 @Override 446 public boolean isVarargsCollector() { 447 return true; 448 } 449 450 @Override 451 protected MethodHandle getTarget() { 452 return target; 453 } 454 455 @Override 456 public MethodHandle asFixedArity() { 457 return target; 458 } 459 460 @Override 461 MethodHandle setVarargs(MemberName member) { 462 if (member.isVarargs()) return this; 463 return asFixedArity(); 464 } 465 466 @Override 467 public MethodHandle asTypeUncached(MethodType newType) { 468 MethodType type = this.type(); 469 int collectArg = type.parameterCount() - 1; 470 int newArity = newType.parameterCount(); 471 if (newArity == collectArg+1 && 472 type.parameterType(collectArg).isAssignableFrom(newType.parameterType(collectArg))) { 473 // if arity and trailing parameter are compatible, do normal thing 474 return asTypeCache = asFixedArity().asType(newType); 475 } 476 // check cache 477 MethodHandle acc = asCollectorCache; 478 if (acc != null && acc.type().parameterCount() == newArity) 479 return asTypeCache = acc.asType(newType); 480 // build and cache a collector 481 int arrayLength = newArity - collectArg; 482 MethodHandle collector; 483 try { 484 collector = asFixedArity().asCollector(arrayType, arrayLength); 485 assert(collector.type().parameterCount() == newArity) : "newArity="+newArity+" but collector="+collector; 486 } catch (IllegalArgumentException ex) { 487 throw new WrongMethodTypeException("cannot build collector", ex); 488 } 489 asCollectorCache = collector; 490 return asTypeCache = collector.asType(newType); 491 } 492 493 @Override 494 boolean viewAsTypeChecks(MethodType newType, boolean strict) { 495 super.viewAsTypeChecks(newType, true); 496 if (strict) return true; 497 // extra assertion for non-strict checks: 498 assert (type().lastParameterType().getComponentType() 499 .isAssignableFrom( 500 newType.lastParameterType().getComponentType())) 501 : Arrays.asList(this, newType); 502 return true; 503 } 504 } 505 506 /** Factory method: Spread selected argument. */ 507 static MethodHandle makeSpreadArguments(MethodHandle target, 508 Class<?> spreadArgType, int spreadArgPos, int spreadArgCount) { 509 MethodType targetType = target.type(); 510 511 for (int i = 0; i < spreadArgCount; i++) { 512 Class<?> arg = VerifyType.spreadArgElementType(spreadArgType, i); 513 if (arg == null) arg = Object.class; 514 targetType = targetType.changeParameterType(spreadArgPos + i, arg); 515 } 516 target = target.asType(targetType); 517 518 MethodType srcType = targetType 519 .replaceParameterTypes(spreadArgPos, spreadArgPos + spreadArgCount, spreadArgType); 520 // Now build a LambdaForm. 521 MethodType lambdaType = srcType.invokerType(); 522 Name[] names = arguments(spreadArgCount + 2, lambdaType); 523 int nameCursor = lambdaType.parameterCount(); 524 int[] indexes = new int[targetType.parameterCount()]; 525 526 for (int i = 0, argIndex = 1; i < targetType.parameterCount() + 1; i++, argIndex++) { 527 Class<?> src = lambdaType.parameterType(i); 528 if (i == spreadArgPos) { 529 // Spread the array. 530 MethodHandle aload = MethodHandles.arrayElementGetter(spreadArgType); 531 Name array = names[argIndex]; 532 names[nameCursor++] = new Name(NF_checkSpreadArgument, array, spreadArgCount); 533 for (int j = 0; j < spreadArgCount; i++, j++) { 534 indexes[i] = nameCursor; 535 names[nameCursor++] = new Name(aload, array, j); 536 } 537 } else if (i < indexes.length) { 538 indexes[i] = argIndex; 539 } 540 } 541 assert(nameCursor == names.length-1); // leave room for the final call 542 543 // Build argument array for the call. 544 Name[] targetArgs = new Name[targetType.parameterCount()]; 545 for (int i = 0; i < targetType.parameterCount(); i++) { 546 int idx = indexes[i]; 547 targetArgs[i] = names[idx]; 548 } 549 names[names.length - 1] = new Name(target, (Object[]) targetArgs); 550 551 LambdaForm form = new LambdaForm("spread", lambdaType.parameterCount(), names); 552 return SimpleMethodHandle.make(srcType, form); 553 } 554 555 static void checkSpreadArgument(Object av, int n) { 556 if (av == null) { 557 if (n == 0) return; 558 } else if (av instanceof Object[]) { 559 int len = ((Object[])av).length; 560 if (len == n) return; 561 } else { 562 int len = java.lang.reflect.Array.getLength(av); 563 if (len == n) return; 564 } 565 // fall through to error: 566 throw newIllegalArgumentException("array is not of length "+n); 567 } 568 569 /** Factory method: Collect or filter selected argument(s). */ 570 static MethodHandle makeCollectArguments(MethodHandle target, 571 MethodHandle collector, int collectArgPos, boolean retainOriginalArgs) { 572 MethodType targetType = target.type(); // (a..., c, [b...])=>r 573 MethodType collectorType = collector.type(); // (b...)=>c 574 int collectArgCount = collectorType.parameterCount(); 575 Class<?> collectValType = collectorType.returnType(); 576 int collectValCount = (collectValType == void.class ? 0 : 1); 577 MethodType srcType = targetType // (a..., [b...])=>r 578 .dropParameterTypes(collectArgPos, collectArgPos+collectValCount); 579 if (!retainOriginalArgs) { // (a..., b...)=>r 580 srcType = srcType.insertParameterTypes(collectArgPos, collectorType.parameterList()); 581 } 582 // in arglist: [0: ...keep1 | cpos: collect... | cpos+cacount: keep2... ] 583 // out arglist: [0: ...keep1 | cpos: collectVal? | cpos+cvcount: keep2... ] 584 // out(retain): [0: ...keep1 | cpos: cV? coll... | cpos+cvc+cac: keep2... ] 585 586 // Now build a LambdaForm. 587 MethodType lambdaType = srcType.invokerType(); 588 Name[] names = arguments(2, lambdaType); 589 final int collectNamePos = names.length - 2; 590 final int targetNamePos = names.length - 1; 591 592 Name[] collectorArgs = Arrays.copyOfRange(names, 1 + collectArgPos, 1 + collectArgPos + collectArgCount); 593 names[collectNamePos] = new Name(collector, (Object[]) collectorArgs); 594 595 // Build argument array for the target. 596 // Incoming LF args to copy are: [ (mh) headArgs collectArgs tailArgs ]. 597 // Output argument array is [ headArgs (collectVal)? (collectArgs)? tailArgs ]. 598 Name[] targetArgs = new Name[targetType.parameterCount()]; 599 int inputArgPos = 1; // incoming LF args to copy to target 600 int targetArgPos = 0; // fill pointer for targetArgs 601 int chunk = collectArgPos; // |headArgs| 602 System.arraycopy(names, inputArgPos, targetArgs, targetArgPos, chunk); 603 inputArgPos += chunk; 604 targetArgPos += chunk; 605 if (collectValType != void.class) { 606 targetArgs[targetArgPos++] = names[collectNamePos]; 607 } 608 chunk = collectArgCount; 609 if (retainOriginalArgs) { 610 System.arraycopy(names, inputArgPos, targetArgs, targetArgPos, chunk); 611 targetArgPos += chunk; // optionally pass on the collected chunk 612 } 613 inputArgPos += chunk; 614 chunk = targetArgs.length - targetArgPos; // all the rest 615 System.arraycopy(names, inputArgPos, targetArgs, targetArgPos, chunk); 616 assert(inputArgPos + chunk == collectNamePos); // use of rest of input args also 617 names[targetNamePos] = new Name(target, (Object[]) targetArgs); 618 619 LambdaForm form = new LambdaForm("collect", lambdaType.parameterCount(), names); 620 return SimpleMethodHandle.make(srcType, form); 621 } 622 623 @LambdaForm.Hidden 624 static 625 MethodHandle selectAlternative(boolean testResult, MethodHandle target, MethodHandle fallback) { 626 if (testResult) { 627 return target; 628 } else { 629 return fallback; 630 } 631 } 632 633 // Intrinsified by C2. Counters are used during parsing to calculate branch frequencies. 634 @LambdaForm.Hidden 635 @jdk.internal.HotSpotIntrinsicCandidate 636 static 637 boolean profileBoolean(boolean result, int[] counters) { 638 // Profile is int[2] where [0] and [1] correspond to false and true occurrences respectively. 639 int idx = result ? 1 : 0; 640 try { 641 counters[idx] = Math.addExact(counters[idx], 1); 642 } catch (ArithmeticException e) { 643 // Avoid continuous overflow by halving the problematic count. 644 counters[idx] = counters[idx] / 2; 645 } 646 return result; 647 } 648 649 // Intrinsified by C2. Returns true if obj is a compile-time constant. 650 @LambdaForm.Hidden 651 @jdk.internal.HotSpotIntrinsicCandidate 652 static 653 boolean isCompileConstant(Object obj) { 654 return false; 655 } 656 657 static 658 MethodHandle makeGuardWithTest(MethodHandle test, 659 MethodHandle target, 660 MethodHandle fallback) { 661 MethodType type = target.type(); 662 assert(test.type().equals(type.changeReturnType(boolean.class)) && fallback.type().equals(type)); 663 MethodType basicType = type.basicType(); 664 LambdaForm form = makeGuardWithTestForm(basicType); 665 BoundMethodHandle mh; 666 try { 667 if (PROFILE_GWT) { 668 int[] counts = new int[2]; 669 mh = (BoundMethodHandle) 670 BoundMethodHandle.speciesData_LLLL().constructor().invokeBasic(type, form, 671 (Object) test, (Object) profile(target), (Object) profile(fallback), counts); 672 } else { 673 mh = (BoundMethodHandle) 674 BoundMethodHandle.speciesData_LLL().constructor().invokeBasic(type, form, 675 (Object) test, (Object) profile(target), (Object) profile(fallback)); 676 } 677 } catch (Throwable ex) { 678 throw uncaughtException(ex); 679 } 680 assert(mh.type() == type); 681 return mh; 682 } 683 684 685 static 686 MethodHandle profile(MethodHandle target) { 687 if (DONT_INLINE_THRESHOLD >= 0) { 688 return makeBlockInliningWrapper(target); 689 } else { 690 return target; 691 } 692 } 693 694 /** 695 * Block inlining during JIT-compilation of a target method handle if it hasn't been invoked enough times. 696 * Corresponding LambdaForm has @DontInline when compiled into bytecode. 697 */ 698 static 699 MethodHandle makeBlockInliningWrapper(MethodHandle target) { 700 LambdaForm lform; 701 if (DONT_INLINE_THRESHOLD > 0) { 702 lform = PRODUCE_BLOCK_INLINING_FORM.apply(target); 703 } else { 704 lform = PRODUCE_REINVOKER_FORM.apply(target); 705 } 706 return new CountingWrapper(target, lform, 707 PRODUCE_BLOCK_INLINING_FORM, PRODUCE_REINVOKER_FORM, 708 DONT_INLINE_THRESHOLD); 709 } 710 711 /** Constructs reinvoker lambda form which block inlining during JIT-compilation for a particular method handle */ 712 private static final Function<MethodHandle, LambdaForm> PRODUCE_BLOCK_INLINING_FORM = new Function<MethodHandle, LambdaForm>() { 713 @Override 714 public LambdaForm apply(MethodHandle target) { 715 return DelegatingMethodHandle.makeReinvokerForm(target, 716 MethodTypeForm.LF_DELEGATE_BLOCK_INLINING, CountingWrapper.class, "reinvoker.dontInline", false, 717 DelegatingMethodHandle.NF_getTarget, CountingWrapper.NF_maybeStopCounting); 718 } 719 }; 720 721 /** Constructs simple reinvoker lambda form for a particular method handle */ 722 private static final Function<MethodHandle, LambdaForm> PRODUCE_REINVOKER_FORM = new Function<MethodHandle, LambdaForm>() { 723 @Override 724 public LambdaForm apply(MethodHandle target) { 725 return DelegatingMethodHandle.makeReinvokerForm(target, 726 MethodTypeForm.LF_DELEGATE, DelegatingMethodHandle.class, DelegatingMethodHandle.NF_getTarget); 727 } 728 }; 729 730 /** 731 * Counting method handle. It has 2 states: counting and non-counting. 732 * It is in counting state for the first n invocations and then transitions to non-counting state. 733 * Behavior in counting and non-counting states is determined by lambda forms produced by 734 * countingFormProducer & nonCountingFormProducer respectively. 735 */ 736 static class CountingWrapper extends DelegatingMethodHandle { 737 private final MethodHandle target; 738 private int count; 739 private Function<MethodHandle, LambdaForm> countingFormProducer; 740 private Function<MethodHandle, LambdaForm> nonCountingFormProducer; 741 private volatile boolean isCounting; 742 743 private CountingWrapper(MethodHandle target, LambdaForm lform, 744 Function<MethodHandle, LambdaForm> countingFromProducer, 745 Function<MethodHandle, LambdaForm> nonCountingFormProducer, 746 int count) { 747 super(target.type(), lform); 748 this.target = target; 749 this.count = count; 750 this.countingFormProducer = countingFromProducer; 751 this.nonCountingFormProducer = nonCountingFormProducer; 752 this.isCounting = (count > 0); 753 } 754 755 @Hidden 756 @Override 757 protected MethodHandle getTarget() { 758 return target; 759 } 760 761 @Override 762 public MethodHandle asTypeUncached(MethodType newType) { 763 MethodHandle newTarget = target.asType(newType); 764 MethodHandle wrapper; 765 if (isCounting) { 766 LambdaForm lform; 767 lform = countingFormProducer.apply(newTarget); 768 wrapper = new CountingWrapper(newTarget, lform, countingFormProducer, nonCountingFormProducer, DONT_INLINE_THRESHOLD); 769 } else { 770 wrapper = newTarget; // no need for a counting wrapper anymore 771 } 772 return (asTypeCache = wrapper); 773 } 774 775 boolean countDown() { 776 int c = count; 777 if (c <= 1) { 778 // Try to limit number of updates. MethodHandle.updateForm() doesn't guarantee LF update visibility. 779 if (isCounting) { 780 isCounting = false; 781 return true; 782 } else { 783 return false; 784 } 785 } else { 786 count = c - 1; 787 return false; 788 } 789 } 790 791 @Hidden 792 static void maybeStopCounting(Object o1) { 793 CountingWrapper wrapper = (CountingWrapper) o1; 794 if (wrapper.countDown()) { 795 // Reached invocation threshold. Replace counting behavior with a non-counting one. 796 LambdaForm lform = wrapper.nonCountingFormProducer.apply(wrapper.target); 797 lform.compileToBytecode(); // speed up warmup by avoiding LF interpretation again after transition 798 wrapper.updateForm(lform); 799 } 800 } 801 802 static final NamedFunction NF_maybeStopCounting; 803 static { 804 Class<?> THIS_CLASS = CountingWrapper.class; 805 try { 806 NF_maybeStopCounting = new NamedFunction(THIS_CLASS.getDeclaredMethod("maybeStopCounting", Object.class)); 807 } catch (ReflectiveOperationException ex) { 808 throw newInternalError(ex); 809 } 810 } 811 } 812 813 static 814 LambdaForm makeGuardWithTestForm(MethodType basicType) { 815 LambdaForm lform = basicType.form().cachedLambdaForm(MethodTypeForm.LF_GWT); 816 if (lform != null) return lform; 817 final int THIS_MH = 0; // the BMH_LLL 818 final int ARG_BASE = 1; // start of incoming arguments 819 final int ARG_LIMIT = ARG_BASE + basicType.parameterCount(); 820 int nameCursor = ARG_LIMIT; 821 final int GET_TEST = nameCursor++; 822 final int GET_TARGET = nameCursor++; 823 final int GET_FALLBACK = nameCursor++; 824 final int GET_COUNTERS = PROFILE_GWT ? nameCursor++ : -1; 825 final int CALL_TEST = nameCursor++; 826 final int PROFILE = (GET_COUNTERS != -1) ? nameCursor++ : -1; 827 final int TEST = nameCursor-1; // previous statement: either PROFILE or CALL_TEST 828 final int SELECT_ALT = nameCursor++; 829 final int CALL_TARGET = nameCursor++; 830 assert(CALL_TARGET == SELECT_ALT+1); // must be true to trigger IBG.emitSelectAlternative 831 832 MethodType lambdaType = basicType.invokerType(); 833 Name[] names = arguments(nameCursor - ARG_LIMIT, lambdaType); 834 835 BoundMethodHandle.SpeciesData data = 836 (GET_COUNTERS != -1) ? BoundMethodHandle.speciesData_LLLL() 837 : BoundMethodHandle.speciesData_LLL(); 838 names[THIS_MH] = names[THIS_MH].withConstraint(data); 839 names[GET_TEST] = new Name(data.getterFunction(0), names[THIS_MH]); 840 names[GET_TARGET] = new Name(data.getterFunction(1), names[THIS_MH]); 841 names[GET_FALLBACK] = new Name(data.getterFunction(2), names[THIS_MH]); 842 if (GET_COUNTERS != -1) { 843 names[GET_COUNTERS] = new Name(data.getterFunction(3), names[THIS_MH]); 844 } 845 Object[] invokeArgs = Arrays.copyOfRange(names, 0, ARG_LIMIT, Object[].class); 846 847 // call test 848 MethodType testType = basicType.changeReturnType(boolean.class).basicType(); 849 invokeArgs[0] = names[GET_TEST]; 850 names[CALL_TEST] = new Name(testType, invokeArgs); 851 852 // profile branch 853 if (PROFILE != -1) { 854 names[PROFILE] = new Name(NF_profileBoolean, names[CALL_TEST], names[GET_COUNTERS]); 855 } 856 // call selectAlternative 857 names[SELECT_ALT] = new Name(getConstantHandle(MH_selectAlternative), names[TEST], names[GET_TARGET], names[GET_FALLBACK]); 858 859 // call target or fallback 860 invokeArgs[0] = names[SELECT_ALT]; 861 names[CALL_TARGET] = new Name(basicType, invokeArgs); 862 863 lform = new LambdaForm("guard", lambdaType.parameterCount(), names, /*forceInline=*/true); 864 865 return basicType.form().setCachedLambdaForm(MethodTypeForm.LF_GWT, lform); 866 } 867 868 /** 869 * The LambdaForm shape for catchException combinator is the following: 870 * <blockquote><pre>{@code 871 * guardWithCatch=Lambda(a0:L,a1:L,a2:L)=>{ 872 * t3:L=BoundMethodHandle$Species_LLLLL.argL0(a0:L); 873 * t4:L=BoundMethodHandle$Species_LLLLL.argL1(a0:L); 874 * t5:L=BoundMethodHandle$Species_LLLLL.argL2(a0:L); 875 * t6:L=BoundMethodHandle$Species_LLLLL.argL3(a0:L); 876 * t7:L=BoundMethodHandle$Species_LLLLL.argL4(a0:L); 877 * t8:L=MethodHandle.invokeBasic(t6:L,a1:L,a2:L); 878 * t9:L=MethodHandleImpl.guardWithCatch(t3:L,t4:L,t5:L,t8:L); 879 * t10:I=MethodHandle.invokeBasic(t7:L,t9:L);t10:I} 880 * }</pre></blockquote> 881 * 882 * argL0 and argL2 are target and catcher method handles. argL1 is exception class. 883 * argL3 and argL4 are auxiliary method handles: argL3 boxes arguments and wraps them into Object[] 884 * (ValueConversions.array()) and argL4 unboxes result if necessary (ValueConversions.unbox()). 885 * 886 * Having t8 and t10 passed outside and not hardcoded into a lambda form allows to share lambda forms 887 * among catchException combinators with the same basic type. 888 */ 889 private static LambdaForm makeGuardWithCatchForm(MethodType basicType) { 890 MethodType lambdaType = basicType.invokerType(); 891 892 LambdaForm lform = basicType.form().cachedLambdaForm(MethodTypeForm.LF_GWC); 893 if (lform != null) { 894 return lform; 895 } 896 final int THIS_MH = 0; // the BMH_LLLLL 897 final int ARG_BASE = 1; // start of incoming arguments 898 final int ARG_LIMIT = ARG_BASE + basicType.parameterCount(); 899 900 int nameCursor = ARG_LIMIT; 901 final int GET_TARGET = nameCursor++; 902 final int GET_CLASS = nameCursor++; 903 final int GET_CATCHER = nameCursor++; 904 final int GET_COLLECT_ARGS = nameCursor++; 905 final int GET_UNBOX_RESULT = nameCursor++; 906 final int BOXED_ARGS = nameCursor++; 907 final int TRY_CATCH = nameCursor++; 908 final int UNBOX_RESULT = nameCursor++; 909 910 Name[] names = arguments(nameCursor - ARG_LIMIT, lambdaType); 911 912 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLLLL(); 913 names[THIS_MH] = names[THIS_MH].withConstraint(data); 914 names[GET_TARGET] = new Name(data.getterFunction(0), names[THIS_MH]); 915 names[GET_CLASS] = new Name(data.getterFunction(1), names[THIS_MH]); 916 names[GET_CATCHER] = new Name(data.getterFunction(2), names[THIS_MH]); 917 names[GET_COLLECT_ARGS] = new Name(data.getterFunction(3), names[THIS_MH]); 918 names[GET_UNBOX_RESULT] = new Name(data.getterFunction(4), names[THIS_MH]); 919 920 // FIXME: rework argument boxing/result unboxing logic for LF interpretation 921 922 // t_{i}:L=MethodHandle.invokeBasic(collectArgs:L,a1:L,...); 923 MethodType collectArgsType = basicType.changeReturnType(Object.class); 924 MethodHandle invokeBasic = MethodHandles.basicInvoker(collectArgsType); 925 Object[] args = new Object[invokeBasic.type().parameterCount()]; 926 args[0] = names[GET_COLLECT_ARGS]; 927 System.arraycopy(names, ARG_BASE, args, 1, ARG_LIMIT-ARG_BASE); 928 names[BOXED_ARGS] = new Name(makeIntrinsic(invokeBasic, Intrinsic.GUARD_WITH_CATCH), args); 929 930 // t_{i+1}:L=MethodHandleImpl.guardWithCatch(target:L,exType:L,catcher:L,t_{i}:L); 931 Object[] gwcArgs = new Object[] {names[GET_TARGET], names[GET_CLASS], names[GET_CATCHER], names[BOXED_ARGS]}; 932 names[TRY_CATCH] = new Name(NF_guardWithCatch, gwcArgs); 933 934 // t_{i+2}:I=MethodHandle.invokeBasic(unbox:L,t_{i+1}:L); 935 MethodHandle invokeBasicUnbox = MethodHandles.basicInvoker(MethodType.methodType(basicType.rtype(), Object.class)); 936 Object[] unboxArgs = new Object[] {names[GET_UNBOX_RESULT], names[TRY_CATCH]}; 937 names[UNBOX_RESULT] = new Name(invokeBasicUnbox, unboxArgs); 938 939 lform = new LambdaForm("guardWithCatch", lambdaType.parameterCount(), names); 940 941 return basicType.form().setCachedLambdaForm(MethodTypeForm.LF_GWC, lform); 942 } 943 944 static 945 MethodHandle makeGuardWithCatch(MethodHandle target, 946 Class<? extends Throwable> exType, 947 MethodHandle catcher) { 948 MethodType type = target.type(); 949 LambdaForm form = makeGuardWithCatchForm(type.basicType()); 950 951 // Prepare auxiliary method handles used during LambdaForm interpretation. 952 // Box arguments and wrap them into Object[]: ValueConversions.array(). 953 MethodType varargsType = type.changeReturnType(Object[].class); 954 MethodHandle collectArgs = varargsArray(type.parameterCount()).asType(varargsType); 955 // Result unboxing: ValueConversions.unbox() OR ValueConversions.identity() OR ValueConversions.ignore(). 956 MethodHandle unboxResult; 957 Class<?> rtype = type.returnType(); 958 if (rtype.isPrimitive()) { 959 if (rtype == void.class) { 960 unboxResult = ValueConversions.ignore(); 961 } else { 962 Wrapper w = Wrapper.forPrimitiveType(type.returnType()); 963 unboxResult = ValueConversions.unboxExact(w); 964 } 965 } else { 966 unboxResult = MethodHandles.identity(Object.class); 967 } 968 969 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLLLL(); 970 BoundMethodHandle mh; 971 try { 972 mh = (BoundMethodHandle) 973 data.constructor().invokeBasic(type, form, (Object) target, (Object) exType, (Object) catcher, 974 (Object) collectArgs, (Object) unboxResult); 975 } catch (Throwable ex) { 976 throw uncaughtException(ex); 977 } 978 assert(mh.type() == type); 979 return mh; 980 } 981 982 /** 983 * Intrinsified during LambdaForm compilation 984 * (see {@link InvokerBytecodeGenerator#emitGuardWithCatch emitGuardWithCatch}). 985 */ 986 @LambdaForm.Hidden 987 static Object guardWithCatch(MethodHandle target, Class<? extends Throwable> exType, MethodHandle catcher, 988 Object... av) throws Throwable { 989 // Use asFixedArity() to avoid unnecessary boxing of last argument for VarargsCollector case. 990 try { 991 return target.asFixedArity().invokeWithArguments(av); 992 } catch (Throwable t) { 993 if (!exType.isInstance(t)) throw t; 994 return catcher.asFixedArity().invokeWithArguments(prepend(t, av)); 995 } 996 } 997 998 /** Prepend an element {@code elem} to an {@code array}. */ 999 @LambdaForm.Hidden 1000 private static Object[] prepend(Object elem, Object[] array) { 1001 Object[] newArray = new Object[array.length+1]; 1002 newArray[0] = elem; 1003 System.arraycopy(array, 0, newArray, 1, array.length); 1004 return newArray; 1005 } 1006 1007 static 1008 MethodHandle throwException(MethodType type) { 1009 assert(Throwable.class.isAssignableFrom(type.parameterType(0))); 1010 int arity = type.parameterCount(); 1011 if (arity > 1) { 1012 MethodHandle mh = throwException(type.dropParameterTypes(1, arity)); 1013 mh = MethodHandles.dropArguments(mh, 1, type.parameterList().subList(1, arity)); 1014 return mh; 1015 } 1016 return makePairwiseConvert(NF_throwException.resolvedHandle(), type, false, true); 1017 } 1018 1019 static <T extends Throwable> Empty throwException(T t) throws T { throw t; } 1020 1021 static MethodHandle[] FAKE_METHOD_HANDLE_INVOKE = new MethodHandle[2]; 1022 static MethodHandle fakeMethodHandleInvoke(MemberName method) { 1023 int idx; 1024 assert(method.isMethodHandleInvoke()); 1025 switch (method.getName()) { 1026 case "invoke": idx = 0; break; 1027 case "invokeExact": idx = 1; break; 1028 default: throw new InternalError(method.getName()); 1029 } 1030 MethodHandle mh = FAKE_METHOD_HANDLE_INVOKE[idx]; 1031 if (mh != null) return mh; 1032 MethodType type = MethodType.methodType(Object.class, UnsupportedOperationException.class, 1033 MethodHandle.class, Object[].class); 1034 mh = throwException(type); 1035 mh = mh.bindTo(new UnsupportedOperationException("cannot reflectively invoke MethodHandle")); 1036 if (!method.getInvocationType().equals(mh.type())) 1037 throw new InternalError(method.toString()); 1038 mh = mh.withInternalMemberName(method, false); 1039 mh = mh.asVarargsCollector(Object[].class); 1040 assert(method.isVarargs()); 1041 FAKE_METHOD_HANDLE_INVOKE[idx] = mh; 1042 return mh; 1043 } 1044 1045 /** 1046 * Create an alias for the method handle which, when called, 1047 * appears to be called from the same class loader and protection domain 1048 * as hostClass. 1049 * This is an expensive no-op unless the method which is called 1050 * is sensitive to its caller. A small number of system methods 1051 * are in this category, including Class.forName and Method.invoke. 1052 */ 1053 static 1054 MethodHandle bindCaller(MethodHandle mh, Class<?> hostClass) { 1055 return BindCaller.bindCaller(mh, hostClass); 1056 } 1057 1058 // Put the whole mess into its own nested class. 1059 // That way we can lazily load the code and set up the constants. 1060 private static class BindCaller { 1061 static 1062 MethodHandle bindCaller(MethodHandle mh, Class<?> hostClass) { 1063 // Do not use this function to inject calls into system classes. 1064 if (hostClass == null 1065 || (hostClass.isArray() || 1066 hostClass.isPrimitive() || 1067 hostClass.getName().startsWith("java.") || 1068 hostClass.getName().startsWith("sun."))) { 1069 throw new InternalError(); // does not happen, and should not anyway 1070 } 1071 // For simplicity, convert mh to a varargs-like method. 1072 MethodHandle vamh = prepareForInvoker(mh); 1073 // Cache the result of makeInjectedInvoker once per argument class. 1074 MethodHandle bccInvoker = CV_makeInjectedInvoker.get(hostClass); 1075 return restoreToType(bccInvoker.bindTo(vamh), mh, hostClass); 1076 } 1077 1078 private static MethodHandle makeInjectedInvoker(Class<?> hostClass) { 1079 Class<?> bcc = UNSAFE.defineAnonymousClass(hostClass, T_BYTES, null); 1080 if (hostClass.getClassLoader() != bcc.getClassLoader()) 1081 throw new InternalError(hostClass.getName()+" (CL)"); 1082 try { 1083 if (hostClass.getProtectionDomain() != bcc.getProtectionDomain()) 1084 throw new InternalError(hostClass.getName()+" (PD)"); 1085 } catch (SecurityException ex) { 1086 // Self-check was blocked by security manager. This is OK. 1087 // In fact the whole try body could be turned into an assertion. 1088 } 1089 try { 1090 MethodHandle init = IMPL_LOOKUP.findStatic(bcc, "init", MethodType.methodType(void.class)); 1091 init.invokeExact(); // force initialization of the class 1092 } catch (Throwable ex) { 1093 throw uncaughtException(ex); 1094 } 1095 MethodHandle bccInvoker; 1096 try { 1097 MethodType invokerMT = MethodType.methodType(Object.class, MethodHandle.class, Object[].class); 1098 bccInvoker = IMPL_LOOKUP.findStatic(bcc, "invoke_V", invokerMT); 1099 } catch (ReflectiveOperationException ex) { 1100 throw uncaughtException(ex); 1101 } 1102 // Test the invoker, to ensure that it really injects into the right place. 1103 try { 1104 MethodHandle vamh = prepareForInvoker(MH_checkCallerClass); 1105 Object ok = bccInvoker.invokeExact(vamh, new Object[]{hostClass, bcc}); 1106 } catch (Throwable ex) { 1107 throw new InternalError(ex); 1108 } 1109 return bccInvoker; 1110 } 1111 private static ClassValue<MethodHandle> CV_makeInjectedInvoker = new ClassValue<MethodHandle>() { 1112 @Override protected MethodHandle computeValue(Class<?> hostClass) { 1113 return makeInjectedInvoker(hostClass); 1114 } 1115 }; 1116 1117 // Adapt mh so that it can be called directly from an injected invoker: 1118 private static MethodHandle prepareForInvoker(MethodHandle mh) { 1119 mh = mh.asFixedArity(); 1120 MethodType mt = mh.type(); 1121 int arity = mt.parameterCount(); 1122 MethodHandle vamh = mh.asType(mt.generic()); 1123 vamh.internalForm().compileToBytecode(); // eliminate LFI stack frames 1124 vamh = vamh.asSpreader(Object[].class, arity); 1125 vamh.internalForm().compileToBytecode(); // eliminate LFI stack frames 1126 return vamh; 1127 } 1128 1129 // Undo the adapter effect of prepareForInvoker: 1130 private static MethodHandle restoreToType(MethodHandle vamh, 1131 MethodHandle original, 1132 Class<?> hostClass) { 1133 MethodType type = original.type(); 1134 MethodHandle mh = vamh.asCollector(Object[].class, type.parameterCount()); 1135 MemberName member = original.internalMemberName(); 1136 mh = mh.asType(type); 1137 mh = new WrappedMember(mh, type, member, original.isInvokeSpecial(), hostClass); 1138 return mh; 1139 } 1140 1141 private static final MethodHandle MH_checkCallerClass; 1142 static { 1143 final Class<?> THIS_CLASS = BindCaller.class; 1144 assert(checkCallerClass(THIS_CLASS, THIS_CLASS)); 1145 try { 1146 MH_checkCallerClass = IMPL_LOOKUP 1147 .findStatic(THIS_CLASS, "checkCallerClass", 1148 MethodType.methodType(boolean.class, Class.class, Class.class)); 1149 assert((boolean) MH_checkCallerClass.invokeExact(THIS_CLASS, THIS_CLASS)); 1150 } catch (Throwable ex) { 1151 throw new InternalError(ex); 1152 } 1153 } 1154 1155 @CallerSensitive 1156 private static boolean checkCallerClass(Class<?> expected, Class<?> expected2) { 1157 // This method is called via MH_checkCallerClass and so it's 1158 // correct to ask for the immediate caller here. 1159 Class<?> actual = Reflection.getCallerClass(); 1160 if (actual != expected && actual != expected2) 1161 throw new InternalError("found "+actual.getName()+", expected "+expected.getName() 1162 +(expected == expected2 ? "" : ", or else "+expected2.getName())); 1163 return true; 1164 } 1165 1166 private static final byte[] T_BYTES; 1167 static { 1168 final Object[] values = {null}; 1169 AccessController.doPrivileged(new PrivilegedAction<>() { 1170 public Void run() { 1171 try { 1172 Class<T> tClass = T.class; 1173 String tName = tClass.getName(); 1174 String tResource = tName.substring(tName.lastIndexOf('.')+1)+".class"; 1175 java.net.URLConnection uconn = tClass.getResource(tResource).openConnection(); 1176 int len = uconn.getContentLength(); 1177 byte[] bytes = new byte[len]; 1178 try (java.io.InputStream str = uconn.getInputStream()) { 1179 int nr = str.read(bytes); 1180 if (nr != len) throw new java.io.IOException(tResource); 1181 } 1182 values[0] = bytes; 1183 } catch (java.io.IOException ex) { 1184 throw new InternalError(ex); 1185 } 1186 return null; 1187 } 1188 }); 1189 T_BYTES = (byte[]) values[0]; 1190 } 1191 1192 // The following class is used as a template for Unsafe.defineAnonymousClass: 1193 private static class T { 1194 static void init() { } // side effect: initializes this class 1195 static Object invoke_V(MethodHandle vamh, Object[] args) throws Throwable { 1196 return vamh.invokeExact(args); 1197 } 1198 } 1199 } 1200 1201 1202 /** This subclass allows a wrapped method handle to be re-associated with an arbitrary member name. */ 1203 private static final class WrappedMember extends DelegatingMethodHandle { 1204 private final MethodHandle target; 1205 private final MemberName member; 1206 private final Class<?> callerClass; 1207 private final boolean isInvokeSpecial; 1208 1209 private WrappedMember(MethodHandle target, MethodType type, 1210 MemberName member, boolean isInvokeSpecial, 1211 Class<?> callerClass) { 1212 super(type, target); 1213 this.target = target; 1214 this.member = member; 1215 this.callerClass = callerClass; 1216 this.isInvokeSpecial = isInvokeSpecial; 1217 } 1218 1219 @Override 1220 MemberName internalMemberName() { 1221 return member; 1222 } 1223 @Override 1224 Class<?> internalCallerClass() { 1225 return callerClass; 1226 } 1227 @Override 1228 boolean isInvokeSpecial() { 1229 return isInvokeSpecial; 1230 } 1231 @Override 1232 protected MethodHandle getTarget() { 1233 return target; 1234 } 1235 @Override 1236 public MethodHandle asTypeUncached(MethodType newType) { 1237 // This MH is an alias for target, except for the MemberName 1238 // Drop the MemberName if there is any conversion. 1239 return asTypeCache = target.asType(newType); 1240 } 1241 } 1242 1243 static MethodHandle makeWrappedMember(MethodHandle target, MemberName member, boolean isInvokeSpecial) { 1244 if (member.equals(target.internalMemberName()) && isInvokeSpecial == target.isInvokeSpecial()) 1245 return target; 1246 return new WrappedMember(target, target.type(), member, isInvokeSpecial, null); 1247 } 1248 1249 /** Intrinsic IDs */ 1250 /*non-public*/ 1251 enum Intrinsic { 1252 SELECT_ALTERNATIVE, 1253 GUARD_WITH_CATCH, 1254 NEW_ARRAY, 1255 ARRAY_LOAD, 1256 ARRAY_STORE, 1257 IDENTITY, 1258 ZERO, 1259 NONE // no intrinsic associated 1260 } 1261 1262 /** Mark arbitrary method handle as intrinsic. 1263 * InvokerBytecodeGenerator uses this info to produce more efficient bytecode shape. */ 1264 private static final class IntrinsicMethodHandle extends DelegatingMethodHandle { 1265 private final MethodHandle target; 1266 private final Intrinsic intrinsicName; 1267 1268 IntrinsicMethodHandle(MethodHandle target, Intrinsic intrinsicName) { 1269 super(target.type(), target); 1270 this.target = target; 1271 this.intrinsicName = intrinsicName; 1272 } 1273 1274 @Override 1275 protected MethodHandle getTarget() { 1276 return target; 1277 } 1278 1279 @Override 1280 Intrinsic intrinsicName() { 1281 return intrinsicName; 1282 } 1283 1284 @Override 1285 public MethodHandle asTypeUncached(MethodType newType) { 1286 // This MH is an alias for target, except for the intrinsic name 1287 // Drop the name if there is any conversion. 1288 return asTypeCache = target.asType(newType); 1289 } 1290 1291 @Override 1292 String internalProperties() { 1293 return super.internalProperties() + 1294 "\n& Intrinsic="+intrinsicName; 1295 } 1296 1297 @Override 1298 public MethodHandle asCollector(Class<?> arrayType, int arrayLength) { 1299 if (intrinsicName == Intrinsic.IDENTITY) { 1300 MethodType resultType = type().asCollectorType(arrayType, arrayLength); 1301 MethodHandle newArray = MethodHandleImpl.varargsArray(arrayType, arrayLength); 1302 return newArray.asType(resultType); 1303 } 1304 return super.asCollector(arrayType, arrayLength); 1305 } 1306 } 1307 1308 static MethodHandle makeIntrinsic(MethodHandle target, Intrinsic intrinsicName) { 1309 if (intrinsicName == target.intrinsicName()) 1310 return target; 1311 return new IntrinsicMethodHandle(target, intrinsicName); 1312 } 1313 1314 static MethodHandle makeIntrinsic(MethodType type, LambdaForm form, Intrinsic intrinsicName) { 1315 return new IntrinsicMethodHandle(SimpleMethodHandle.make(type, form), intrinsicName); 1316 } 1317 1318 /// Collection of multiple arguments. 1319 1320 private static MethodHandle findCollector(String name, int nargs, Class<?> rtype, Class<?>... ptypes) { 1321 MethodType type = MethodType.genericMethodType(nargs) 1322 .changeReturnType(rtype) 1323 .insertParameterTypes(0, ptypes); 1324 try { 1325 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, name, type); 1326 } catch (ReflectiveOperationException ex) { 1327 return null; 1328 } 1329 } 1330 1331 private static final Object[] NO_ARGS_ARRAY = {}; 1332 private static Object[] makeArray(Object... args) { return args; } 1333 private static Object[] array() { return NO_ARGS_ARRAY; } 1334 private static Object[] array(Object a0) 1335 { return makeArray(a0); } 1336 private static Object[] array(Object a0, Object a1) 1337 { return makeArray(a0, a1); } 1338 private static Object[] array(Object a0, Object a1, Object a2) 1339 { return makeArray(a0, a1, a2); } 1340 private static Object[] array(Object a0, Object a1, Object a2, Object a3) 1341 { return makeArray(a0, a1, a2, a3); } 1342 private static Object[] array(Object a0, Object a1, Object a2, Object a3, 1343 Object a4) 1344 { return makeArray(a0, a1, a2, a3, a4); } 1345 private static Object[] array(Object a0, Object a1, Object a2, Object a3, 1346 Object a4, Object a5) 1347 { return makeArray(a0, a1, a2, a3, a4, a5); } 1348 private static Object[] array(Object a0, Object a1, Object a2, Object a3, 1349 Object a4, Object a5, Object a6) 1350 { return makeArray(a0, a1, a2, a3, a4, a5, a6); } 1351 private static Object[] array(Object a0, Object a1, Object a2, Object a3, 1352 Object a4, Object a5, Object a6, Object a7) 1353 { return makeArray(a0, a1, a2, a3, a4, a5, a6, a7); } 1354 private static Object[] array(Object a0, Object a1, Object a2, Object a3, 1355 Object a4, Object a5, Object a6, Object a7, 1356 Object a8) 1357 { return makeArray(a0, a1, a2, a3, a4, a5, a6, a7, a8); } 1358 private static Object[] array(Object a0, Object a1, Object a2, Object a3, 1359 Object a4, Object a5, Object a6, Object a7, 1360 Object a8, Object a9) 1361 { return makeArray(a0, a1, a2, a3, a4, a5, a6, a7, a8, a9); } 1362 1363 private static final int ARRAYS_COUNT = 11; 1364 private static final @Stable MethodHandle[] ARRAYS = new MethodHandle[MAX_ARITY + 1]; 1365 1366 // filling versions of the above: 1367 // using Integer len instead of int len and no varargs to avoid bootstrapping problems 1368 private static Object[] fillNewArray(Integer len, Object[] /*not ...*/ args) { 1369 Object[] a = new Object[len]; 1370 fillWithArguments(a, 0, args); 1371 return a; 1372 } 1373 private static Object[] fillNewTypedArray(Object[] example, Integer len, Object[] /*not ...*/ args) { 1374 Object[] a = Arrays.copyOf(example, len); 1375 assert(a.getClass() != Object[].class); 1376 fillWithArguments(a, 0, args); 1377 return a; 1378 } 1379 private static void fillWithArguments(Object[] a, int pos, Object... args) { 1380 System.arraycopy(args, 0, a, pos, args.length); 1381 } 1382 // using Integer pos instead of int pos to avoid bootstrapping problems 1383 private static Object[] fillArray(Integer pos, Object[] a, Object a0) 1384 { fillWithArguments(a, pos, a0); return a; } 1385 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1) 1386 { fillWithArguments(a, pos, a0, a1); return a; } 1387 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1, Object a2) 1388 { fillWithArguments(a, pos, a0, a1, a2); return a; } 1389 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1, Object a2, Object a3) 1390 { fillWithArguments(a, pos, a0, a1, a2, a3); return a; } 1391 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1, Object a2, Object a3, 1392 Object a4) 1393 { fillWithArguments(a, pos, a0, a1, a2, a3, a4); return a; } 1394 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1, Object a2, Object a3, 1395 Object a4, Object a5) 1396 { fillWithArguments(a, pos, a0, a1, a2, a3, a4, a5); return a; } 1397 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1, Object a2, Object a3, 1398 Object a4, Object a5, Object a6) 1399 { fillWithArguments(a, pos, a0, a1, a2, a3, a4, a5, a6); return a; } 1400 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1, Object a2, Object a3, 1401 Object a4, Object a5, Object a6, Object a7) 1402 { fillWithArguments(a, pos, a0, a1, a2, a3, a4, a5, a6, a7); return a; } 1403 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1, Object a2, Object a3, 1404 Object a4, Object a5, Object a6, Object a7, 1405 Object a8) 1406 { fillWithArguments(a, pos, a0, a1, a2, a3, a4, a5, a6, a7, a8); return a; } 1407 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1, Object a2, Object a3, 1408 Object a4, Object a5, Object a6, Object a7, 1409 Object a8, Object a9) 1410 { fillWithArguments(a, pos, a0, a1, a2, a3, a4, a5, a6, a7, a8, a9); return a; } 1411 1412 private static final int FILL_ARRAYS_COUNT = 11; // current number of fillArray methods 1413 private static final @Stable MethodHandle[] FILL_ARRAYS = new MethodHandle[FILL_ARRAYS_COUNT]; 1414 1415 private static MethodHandle getFillArray(int count) { 1416 assert (count > 0 && count < FILL_ARRAYS_COUNT); 1417 MethodHandle mh = FILL_ARRAYS[count]; 1418 if (mh != null) { 1419 return mh; 1420 } 1421 mh = findCollector("fillArray", count, Object[].class, Integer.class, Object[].class); 1422 FILL_ARRAYS[count] = mh; 1423 return mh; 1424 } 1425 1426 private static Object copyAsPrimitiveArray(Wrapper w, Object... boxes) { 1427 Object a = w.makeArray(boxes.length); 1428 w.copyArrayUnboxing(boxes, 0, a, 0, boxes.length); 1429 return a; 1430 } 1431 1432 /** Return a method handle that takes the indicated number of Object 1433 * arguments and returns an Object array of them, as if for varargs. 1434 */ 1435 static MethodHandle varargsArray(int nargs) { 1436 MethodHandle mh = ARRAYS[nargs]; 1437 if (mh != null) { 1438 return mh; 1439 } 1440 if (nargs < ARRAYS_COUNT) { 1441 mh = findCollector("array", nargs, Object[].class); 1442 } else { 1443 mh = buildVarargsArray(getConstantHandle(MH_fillNewArray), 1444 getConstantHandle(MH_arrayIdentity), nargs); 1445 } 1446 assert(assertCorrectArity(mh, nargs)); 1447 mh = makeIntrinsic(mh, Intrinsic.NEW_ARRAY); 1448 return ARRAYS[nargs] = mh; 1449 } 1450 1451 private static boolean assertCorrectArity(MethodHandle mh, int arity) { 1452 assert(mh.type().parameterCount() == arity) : "arity != "+arity+": "+mh; 1453 return true; 1454 } 1455 1456 // Array identity function (used as getConstantHandle(MH_arrayIdentity)). 1457 static <T> T[] identity(T[] x) { 1458 return x; 1459 } 1460 1461 private static MethodHandle buildVarargsArray(MethodHandle newArray, MethodHandle finisher, int nargs) { 1462 // Build up the result mh as a sequence of fills like this: 1463 // finisher(fill(fill(newArrayWA(23,x1..x10),10,x11..x20),20,x21..x23)) 1464 // The various fill(_,10*I,___*[J]) are reusable. 1465 int leftLen = Math.min(nargs, LEFT_ARGS); // absorb some arguments immediately 1466 int rightLen = nargs - leftLen; 1467 MethodHandle leftCollector = newArray.bindTo(nargs); 1468 leftCollector = leftCollector.asCollector(Object[].class, leftLen); 1469 MethodHandle mh = finisher; 1470 if (rightLen > 0) { 1471 MethodHandle rightFiller = fillToRight(LEFT_ARGS + rightLen); 1472 if (mh.equals(getConstantHandle(MH_arrayIdentity))) 1473 mh = rightFiller; 1474 else 1475 mh = MethodHandles.collectArguments(mh, 0, rightFiller); 1476 } 1477 if (mh.equals(getConstantHandle(MH_arrayIdentity))) 1478 mh = leftCollector; 1479 else 1480 mh = MethodHandles.collectArguments(mh, 0, leftCollector); 1481 return mh; 1482 } 1483 1484 private static final int LEFT_ARGS = FILL_ARRAYS_COUNT - 1; 1485 private static final @Stable MethodHandle[] FILL_ARRAY_TO_RIGHT = new MethodHandle[MAX_ARITY+1]; 1486 /** fill_array_to_right(N).invoke(a, argL..arg[N-1]) 1487 * fills a[L]..a[N-1] with corresponding arguments, 1488 * and then returns a. The value L is a global constant (LEFT_ARGS). 1489 */ 1490 private static MethodHandle fillToRight(int nargs) { 1491 MethodHandle filler = FILL_ARRAY_TO_RIGHT[nargs]; 1492 if (filler != null) return filler; 1493 filler = buildFiller(nargs); 1494 assert(assertCorrectArity(filler, nargs - LEFT_ARGS + 1)); 1495 return FILL_ARRAY_TO_RIGHT[nargs] = filler; 1496 } 1497 private static MethodHandle buildFiller(int nargs) { 1498 if (nargs <= LEFT_ARGS) 1499 return getConstantHandle(MH_arrayIdentity); // no args to fill; return the array unchanged 1500 // we need room for both mh and a in mh.invoke(a, arg*[nargs]) 1501 final int CHUNK = LEFT_ARGS; 1502 int rightLen = nargs % CHUNK; 1503 int midLen = nargs - rightLen; 1504 if (rightLen == 0) { 1505 midLen = nargs - (rightLen = CHUNK); 1506 if (FILL_ARRAY_TO_RIGHT[midLen] == null) { 1507 // build some precursors from left to right 1508 for (int j = LEFT_ARGS % CHUNK; j < midLen; j += CHUNK) 1509 if (j > LEFT_ARGS) fillToRight(j); 1510 } 1511 } 1512 if (midLen < LEFT_ARGS) rightLen = nargs - (midLen = LEFT_ARGS); 1513 assert(rightLen > 0); 1514 MethodHandle midFill = fillToRight(midLen); // recursive fill 1515 MethodHandle rightFill = getFillArray(rightLen).bindTo(midLen); // [midLen..nargs-1] 1516 assert(midFill.type().parameterCount() == 1 + midLen - LEFT_ARGS); 1517 assert(rightFill.type().parameterCount() == 1 + rightLen); 1518 1519 // Combine the two fills: 1520 // right(mid(a, x10..x19), x20..x23) 1521 // The final product will look like this: 1522 // right(mid(newArrayLeft(24, x0..x9), x10..x19), x20..x23) 1523 if (midLen == LEFT_ARGS) 1524 return rightFill; 1525 else 1526 return MethodHandles.collectArguments(rightFill, 0, midFill); 1527 } 1528 1529 // Type-polymorphic version of varargs maker. 1530 private static final ClassValue<MethodHandle[]> TYPED_COLLECTORS 1531 = new ClassValue<MethodHandle[]>() { 1532 @Override 1533 protected MethodHandle[] computeValue(Class<?> type) { 1534 return new MethodHandle[256]; 1535 } 1536 }; 1537 1538 static final int MAX_JVM_ARITY = 255; // limit imposed by the JVM 1539 1540 /** Return a method handle that takes the indicated number of 1541 * typed arguments and returns an array of them. 1542 * The type argument is the array type. 1543 */ 1544 static MethodHandle varargsArray(Class<?> arrayType, int nargs) { 1545 Class<?> elemType = arrayType.getComponentType(); 1546 if (elemType == null) throw new IllegalArgumentException("not an array: "+arrayType); 1547 // FIXME: Need more special casing and caching here. 1548 if (nargs >= MAX_JVM_ARITY/2 - 1) { 1549 int slots = nargs; 1550 final int MAX_ARRAY_SLOTS = MAX_JVM_ARITY - 1; // 1 for receiver MH 1551 if (slots <= MAX_ARRAY_SLOTS && elemType.isPrimitive()) 1552 slots *= Wrapper.forPrimitiveType(elemType).stackSlots(); 1553 if (slots > MAX_ARRAY_SLOTS) 1554 throw new IllegalArgumentException("too many arguments: "+arrayType.getSimpleName()+", length "+nargs); 1555 } 1556 if (elemType == Object.class) 1557 return varargsArray(nargs); 1558 // other cases: primitive arrays, subtypes of Object[] 1559 MethodHandle cache[] = TYPED_COLLECTORS.get(elemType); 1560 MethodHandle mh = nargs < cache.length ? cache[nargs] : null; 1561 if (mh != null) return mh; 1562 if (nargs == 0) { 1563 Object example = java.lang.reflect.Array.newInstance(arrayType.getComponentType(), 0); 1564 mh = MethodHandles.constant(arrayType, example); 1565 } else if (elemType.isPrimitive()) { 1566 MethodHandle builder = getConstantHandle(MH_fillNewArray); 1567 MethodHandle producer = buildArrayProducer(arrayType); 1568 mh = buildVarargsArray(builder, producer, nargs); 1569 } else { 1570 Class<? extends Object[]> objArrayType = arrayType.asSubclass(Object[].class); 1571 Object[] example = Arrays.copyOf(NO_ARGS_ARRAY, 0, objArrayType); 1572 MethodHandle builder = getConstantHandle(MH_fillNewTypedArray).bindTo(example); 1573 MethodHandle producer = getConstantHandle(MH_arrayIdentity); // must be weakly typed 1574 mh = buildVarargsArray(builder, producer, nargs); 1575 } 1576 mh = mh.asType(MethodType.methodType(arrayType, Collections.<Class<?>>nCopies(nargs, elemType))); 1577 mh = makeIntrinsic(mh, Intrinsic.NEW_ARRAY); 1578 assert(assertCorrectArity(mh, nargs)); 1579 if (nargs < cache.length) 1580 cache[nargs] = mh; 1581 return mh; 1582 } 1583 1584 private static MethodHandle buildArrayProducer(Class<?> arrayType) { 1585 Class<?> elemType = arrayType.getComponentType(); 1586 assert(elemType.isPrimitive()); 1587 return getConstantHandle(MH_copyAsPrimitiveArray).bindTo(Wrapper.forPrimitiveType(elemType)); 1588 } 1589 1590 /*non-public*/ static void assertSame(Object mh1, Object mh2) { 1591 if (mh1 != mh2) { 1592 String msg = String.format("mh1 != mh2: mh1 = %s (form: %s); mh2 = %s (form: %s)", 1593 mh1, ((MethodHandle)mh1).form, 1594 mh2, ((MethodHandle)mh2).form); 1595 throw newInternalError(msg); 1596 } 1597 } 1598 1599 // Local constant functions: 1600 /*non-public*/ static final NamedFunction 1601 NF_checkSpreadArgument, 1602 NF_guardWithCatch, 1603 NF_throwException, 1604 NF_profileBoolean; 1605 1606 static { 1607 try { 1608 NF_checkSpreadArgument = new NamedFunction(MethodHandleImpl.class 1609 .getDeclaredMethod("checkSpreadArgument", Object.class, int.class)); 1610 NF_guardWithCatch = new NamedFunction(MethodHandleImpl.class 1611 .getDeclaredMethod("guardWithCatch", MethodHandle.class, Class.class, 1612 MethodHandle.class, Object[].class)); 1613 NF_throwException = new NamedFunction(MethodHandleImpl.class 1614 .getDeclaredMethod("throwException", Throwable.class)); 1615 NF_profileBoolean = new NamedFunction(MethodHandleImpl.class 1616 .getDeclaredMethod("profileBoolean", boolean.class, int[].class)); 1617 } catch (ReflectiveOperationException ex) { 1618 throw newInternalError(ex); 1619 } 1620 } 1621 1622 // Indexes into constant method handles: 1623 private static final int 1624 MH_cast = 0, 1625 MH_selectAlternative = 1, 1626 MH_copyAsPrimitiveArray = 2, 1627 MH_fillNewTypedArray = 3, 1628 MH_fillNewArray = 4, 1629 MH_arrayIdentity = 5, 1630 MH_LIMIT = 6; 1631 1632 private static MethodHandle getConstantHandle(int idx) { 1633 MethodHandle handle = HANDLES[idx]; 1634 if (handle != null) { 1635 return handle; 1636 } 1637 return setCachedHandle(idx, makeConstantHandle(idx)); 1638 } 1639 1640 private static synchronized MethodHandle setCachedHandle(int idx, final MethodHandle method) { 1641 // Simulate a CAS, to avoid racy duplication of results. 1642 MethodHandle prev = HANDLES[idx]; 1643 if (prev != null) { 1644 return prev; 1645 } 1646 HANDLES[idx] = method; 1647 return method; 1648 } 1649 1650 // Local constant method handles: 1651 private static final @Stable MethodHandle[] HANDLES = new MethodHandle[MH_LIMIT]; 1652 1653 private static MethodHandle makeConstantHandle(int idx) { 1654 try { 1655 switch (idx) { 1656 case MH_cast: 1657 return IMPL_LOOKUP.findVirtual(Class.class, "cast", 1658 MethodType.methodType(Object.class, Object.class)); 1659 case MH_copyAsPrimitiveArray: 1660 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "copyAsPrimitiveArray", 1661 MethodType.methodType(Object.class, Wrapper.class, Object[].class)); 1662 case MH_arrayIdentity: 1663 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "identity", 1664 MethodType.methodType(Object[].class, Object[].class)); 1665 case MH_fillNewArray: 1666 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "fillNewArray", 1667 MethodType.methodType(Object[].class, Integer.class, Object[].class)); 1668 case MH_fillNewTypedArray: 1669 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "fillNewTypedArray", 1670 MethodType.methodType(Object[].class, Object[].class, Integer.class, Object[].class)); 1671 case MH_selectAlternative: 1672 return makeIntrinsic(IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "selectAlternative", 1673 MethodType.methodType(MethodHandle.class, boolean.class, MethodHandle.class, MethodHandle.class)), 1674 Intrinsic.SELECT_ALTERNATIVE); 1675 } 1676 } catch (ReflectiveOperationException ex) { 1677 throw newInternalError(ex); 1678 } 1679 throw newInternalError("Unknown function index: " + idx); 1680 } 1681 }