1 /*
2 * Copyright (c) 2008, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.lang.invoke;
27
28 import jdk.internal.misc.JavaLangInvokeAccess;
29 import jdk.internal.misc.SharedSecrets;
30 import jdk.internal.org.objectweb.asm.AnnotationVisitor;
31 import jdk.internal.org.objectweb.asm.ClassWriter;
32 import jdk.internal.org.objectweb.asm.MethodVisitor;
33 import jdk.internal.reflect.CallerSensitive;
34 import jdk.internal.reflect.Reflection;
35 import jdk.internal.vm.annotation.ForceInline;
36 import jdk.internal.vm.annotation.Stable;
37 import sun.invoke.empty.Empty;
38 import sun.invoke.util.ValueConversions;
39 import sun.invoke.util.VerifyType;
40 import sun.invoke.util.Wrapper;
41
42 import java.lang.reflect.Array;
43 import java.util.Arrays;
44 import java.util.Collections;
45 import java.util.Iterator;
46 import java.util.List;
47 import java.util.Map;
48 import java.util.function.Function;
49 import java.util.stream.Stream;
50
51 import static java.lang.invoke.LambdaForm.*;
52 import static java.lang.invoke.MethodHandleStatics.*;
53 import static java.lang.invoke.MethodHandles.Lookup.IMPL_LOOKUP;
54 import static jdk.internal.org.objectweb.asm.Opcodes.*;
55
56 /**
57 * Trusted implementation code for MethodHandle.
58 * @author jrose
59 */
60 /*non-public*/ abstract class MethodHandleImpl {
61
62 /// Factory methods to create method handles:
63
64 static MethodHandle makeArrayElementAccessor(Class<?> arrayClass, ArrayAccess access) {
65 if (arrayClass == Object[].class) {
66 return ArrayAccess.objectAccessor(access);
67 }
68 if (!arrayClass.isArray())
69 throw newIllegalArgumentException("not an array: "+arrayClass);
70 MethodHandle[] cache = ArrayAccessor.TYPED_ACCESSORS.get(arrayClass);
71 int cacheIndex = ArrayAccess.cacheIndex(access);
72 MethodHandle mh = cache[cacheIndex];
73 if (mh != null) return mh;
74 mh = ArrayAccessor.getAccessor(arrayClass, access);
75 MethodType correctType = ArrayAccessor.correctType(arrayClass, access);
76 if (mh.type() != correctType) {
77 assert(mh.type().parameterType(0) == Object[].class);
78 /* if access == SET */ assert(access != ArrayAccess.SET || mh.type().parameterType(2) == Object.class);
79 /* if access == GET */ assert(access != ArrayAccess.GET ||
80 (mh.type().returnType() == Object.class &&
81 correctType.parameterType(0).getComponentType() == correctType.returnType()));
82 // safe to view non-strictly, because element type follows from array type
83 mh = mh.viewAsType(correctType, false);
84 }
85 mh = makeIntrinsic(mh, ArrayAccess.intrinsic(access));
86 // Atomically update accessor cache.
87 synchronized(cache) {
88 if (cache[cacheIndex] == null) {
89 cache[cacheIndex] = mh;
90 } else {
91 // Throw away newly constructed accessor and use cached version.
92 mh = cache[cacheIndex];
93 }
94 }
95 return mh;
96 }
97
98 enum ArrayAccess {
99 GET, SET, LENGTH;
100
101 // As ArrayAccess and ArrayAccessor have a circular dependency, the ArrayAccess properties cannot be stored in
102 // final fields.
103
104 static String opName(ArrayAccess a) {
105 switch (a) {
106 case GET: return "getElement";
107 case SET: return "setElement";
108 case LENGTH: return "length";
109 }
110 throw unmatchedArrayAccess(a);
111 }
112
113 static MethodHandle objectAccessor(ArrayAccess a) {
114 switch (a) {
115 case GET: return ArrayAccessor.OBJECT_ARRAY_GETTER;
116 case SET: return ArrayAccessor.OBJECT_ARRAY_SETTER;
117 case LENGTH: return ArrayAccessor.OBJECT_ARRAY_LENGTH;
118 }
119 throw unmatchedArrayAccess(a);
120 }
121
122 static int cacheIndex(ArrayAccess a) {
123 switch (a) {
124 case GET: return ArrayAccessor.GETTER_INDEX;
125 case SET: return ArrayAccessor.SETTER_INDEX;
126 case LENGTH: return ArrayAccessor.LENGTH_INDEX;
127 }
128 throw unmatchedArrayAccess(a);
129 }
130
131 static Intrinsic intrinsic(ArrayAccess a) {
132 switch (a) {
133 case GET: return Intrinsic.ARRAY_LOAD;
134 case SET: return Intrinsic.ARRAY_STORE;
135 case LENGTH: return Intrinsic.ARRAY_LENGTH;
136 }
137 throw unmatchedArrayAccess(a);
138 }
139 }
140
141 static InternalError unmatchedArrayAccess(ArrayAccess a) {
142 return newInternalError("should not reach here (unmatched ArrayAccess: " + a + ")");
143 }
144
145 static final class ArrayAccessor {
146 /// Support for array element and length access
147 static final int GETTER_INDEX = 0, SETTER_INDEX = 1, LENGTH_INDEX = 2, INDEX_LIMIT = 3;
148 static final ClassValue<MethodHandle[]> TYPED_ACCESSORS
149 = new ClassValue<MethodHandle[]>() {
150 @Override
151 protected MethodHandle[] computeValue(Class<?> type) {
152 return new MethodHandle[INDEX_LIMIT];
153 }
154 };
155 static final MethodHandle OBJECT_ARRAY_GETTER, OBJECT_ARRAY_SETTER, OBJECT_ARRAY_LENGTH;
156 static {
157 MethodHandle[] cache = TYPED_ACCESSORS.get(Object[].class);
158 cache[GETTER_INDEX] = OBJECT_ARRAY_GETTER = makeIntrinsic(getAccessor(Object[].class, ArrayAccess.GET), Intrinsic.ARRAY_LOAD);
159 cache[SETTER_INDEX] = OBJECT_ARRAY_SETTER = makeIntrinsic(getAccessor(Object[].class, ArrayAccess.SET), Intrinsic.ARRAY_STORE);
160 cache[LENGTH_INDEX] = OBJECT_ARRAY_LENGTH = makeIntrinsic(getAccessor(Object[].class, ArrayAccess.LENGTH), Intrinsic.ARRAY_LENGTH);
161
162 assert(InvokerBytecodeGenerator.isStaticallyInvocable(ArrayAccessor.OBJECT_ARRAY_GETTER.internalMemberName()));
163 assert(InvokerBytecodeGenerator.isStaticallyInvocable(ArrayAccessor.OBJECT_ARRAY_SETTER.internalMemberName()));
164 assert(InvokerBytecodeGenerator.isStaticallyInvocable(ArrayAccessor.OBJECT_ARRAY_LENGTH.internalMemberName()));
165 }
166
167 static int getElementI(int[] a, int i) { return a[i]; }
168 static long getElementJ(long[] a, int i) { return a[i]; }
169 static float getElementF(float[] a, int i) { return a[i]; }
170 static double getElementD(double[] a, int i) { return a[i]; }
171 static boolean getElementZ(boolean[] a, int i) { return a[i]; }
172 static byte getElementB(byte[] a, int i) { return a[i]; }
173 static short getElementS(short[] a, int i) { return a[i]; }
174 static char getElementC(char[] a, int i) { return a[i]; }
175 static Object getElementL(Object[] a, int i) { return a[i]; }
176
177 static void setElementI(int[] a, int i, int x) { a[i] = x; }
178 static void setElementJ(long[] a, int i, long x) { a[i] = x; }
179 static void setElementF(float[] a, int i, float x) { a[i] = x; }
180 static void setElementD(double[] a, int i, double x) { a[i] = x; }
181 static void setElementZ(boolean[] a, int i, boolean x) { a[i] = x; }
182 static void setElementB(byte[] a, int i, byte x) { a[i] = x; }
183 static void setElementS(short[] a, int i, short x) { a[i] = x; }
184 static void setElementC(char[] a, int i, char x) { a[i] = x; }
185 static void setElementL(Object[] a, int i, Object x) { a[i] = x; }
186
187 static int lengthI(int[] a) { return a.length; }
188 static int lengthJ(long[] a) { return a.length; }
189 static int lengthF(float[] a) { return a.length; }
190 static int lengthD(double[] a) { return a.length; }
191 static int lengthZ(boolean[] a) { return a.length; }
192 static int lengthB(byte[] a) { return a.length; }
193 static int lengthS(short[] a) { return a.length; }
194 static int lengthC(char[] a) { return a.length; }
195 static int lengthL(Object[] a) { return a.length; }
196
197 static String name(Class<?> arrayClass, ArrayAccess access) {
198 Class<?> elemClass = arrayClass.getComponentType();
199 if (elemClass == null) throw newIllegalArgumentException("not an array", arrayClass);
200 return ArrayAccess.opName(access) + Wrapper.basicTypeChar(elemClass);
201 }
202 static MethodType type(Class<?> arrayClass, ArrayAccess access) {
203 Class<?> elemClass = arrayClass.getComponentType();
204 Class<?> arrayArgClass = arrayClass;
205 if (!elemClass.isPrimitive()) {
206 arrayArgClass = Object[].class;
207 elemClass = Object.class;
208 }
209 switch (access) {
210 case GET: return MethodType.methodType(elemClass, arrayArgClass, int.class);
211 case SET: return MethodType.methodType(void.class, arrayArgClass, int.class, elemClass);
212 case LENGTH: return MethodType.methodType(int.class, arrayArgClass);
213 }
214 throw unmatchedArrayAccess(access);
215 }
216 static MethodType correctType(Class<?> arrayClass, ArrayAccess access) {
217 Class<?> elemClass = arrayClass.getComponentType();
218 switch (access) {
219 case GET: return MethodType.methodType(elemClass, arrayClass, int.class);
220 case SET: return MethodType.methodType(void.class, arrayClass, int.class, elemClass);
221 case LENGTH: return MethodType.methodType(int.class, arrayClass);
222 }
223 throw unmatchedArrayAccess(access);
224 }
225 static MethodHandle getAccessor(Class<?> arrayClass, ArrayAccess access) {
226 String name = name(arrayClass, access);
227 MethodType type = type(arrayClass, access);
228 try {
229 return IMPL_LOOKUP.findStatic(ArrayAccessor.class, name, type);
230 } catch (ReflectiveOperationException ex) {
231 throw uncaughtException(ex);
232 }
233 }
234 }
235
236 /**
237 * Create a JVM-level adapter method handle to conform the given method
238 * handle to the similar newType, using only pairwise argument conversions.
239 * For each argument, convert incoming argument to the exact type needed.
240 * The argument conversions allowed are casting, boxing and unboxing,
241 * integral widening or narrowing, and floating point widening or narrowing.
242 * @param srcType required call type
243 * @param target original method handle
244 * @param strict if true, only asType conversions are allowed; if false, explicitCastArguments conversions allowed
245 * @param monobox if true, unboxing conversions are assumed to be exactly typed (Integer to int only, not long or double)
246 * @return an adapter to the original handle with the desired new type,
247 * or the original target if the types are already identical
248 * or null if the adaptation cannot be made
249 */
250 static MethodHandle makePairwiseConvert(MethodHandle target, MethodType srcType,
251 boolean strict, boolean monobox) {
252 MethodType dstType = target.type();
253 if (srcType == dstType)
254 return target;
255 return makePairwiseConvertByEditor(target, srcType, strict, monobox);
256 }
257
258 private static int countNonNull(Object[] array) {
259 int count = 0;
260 for (Object x : array) {
261 if (x != null) ++count;
262 }
263 return count;
264 }
265
266 static MethodHandle makePairwiseConvertByEditor(MethodHandle target, MethodType srcType,
267 boolean strict, boolean monobox) {
268 Object[] convSpecs = computeValueConversions(srcType, target.type(), strict, monobox);
269 int convCount = countNonNull(convSpecs);
270 if (convCount == 0)
271 return target.viewAsType(srcType, strict);
272 MethodType basicSrcType = srcType.basicType();
273 MethodType midType = target.type().basicType();
274 BoundMethodHandle mh = target.rebind();
275 // FIXME: Reduce number of bindings when there is more than one Class conversion.
276 // FIXME: Reduce number of bindings when there are repeated conversions.
277 for (int i = 0; i < convSpecs.length-1; i++) {
278 Object convSpec = convSpecs[i];
279 if (convSpec == null) continue;
280 MethodHandle fn;
281 if (convSpec instanceof Class) {
282 fn = getConstantHandle(MH_cast).bindTo(convSpec);
283 } else {
284 fn = (MethodHandle) convSpec;
285 }
286 Class<?> newType = basicSrcType.parameterType(i);
287 if (--convCount == 0)
288 midType = srcType;
289 else
290 midType = midType.changeParameterType(i, newType);
291 LambdaForm form2 = mh.editor().filterArgumentForm(1+i, BasicType.basicType(newType));
292 mh = mh.copyWithExtendL(midType, form2, fn);
293 mh = mh.rebind();
294 }
295 Object convSpec = convSpecs[convSpecs.length-1];
296 if (convSpec != null) {
297 MethodHandle fn;
298 if (convSpec instanceof Class) {
299 if (convSpec == void.class)
300 fn = null;
301 else
302 fn = getConstantHandle(MH_cast).bindTo(convSpec);
303 } else {
304 fn = (MethodHandle) convSpec;
305 }
306 Class<?> newType = basicSrcType.returnType();
307 assert(--convCount == 0);
308 midType = srcType;
309 if (fn != null) {
310 mh = mh.rebind(); // rebind if too complex
311 LambdaForm form2 = mh.editor().filterReturnForm(BasicType.basicType(newType), false);
312 mh = mh.copyWithExtendL(midType, form2, fn);
313 } else {
314 LambdaForm form2 = mh.editor().filterReturnForm(BasicType.basicType(newType), true);
315 mh = mh.copyWith(midType, form2);
316 }
317 }
318 assert(convCount == 0);
319 assert(mh.type().equals(srcType));
320 return mh;
321 }
322
323 static MethodHandle makePairwiseConvertIndirect(MethodHandle target, MethodType srcType,
324 boolean strict, boolean monobox) {
325 assert(target.type().parameterCount() == srcType.parameterCount());
326 // Calculate extra arguments (temporaries) required in the names array.
327 Object[] convSpecs = computeValueConversions(srcType, target.type(), strict, monobox);
328 final int INARG_COUNT = srcType.parameterCount();
329 int convCount = countNonNull(convSpecs);
330 boolean retConv = (convSpecs[INARG_COUNT] != null);
331 boolean retVoid = srcType.returnType() == void.class;
332 if (retConv && retVoid) {
333 convCount -= 1;
334 retConv = false;
335 }
336
337 final int IN_MH = 0;
338 final int INARG_BASE = 1;
339 final int INARG_LIMIT = INARG_BASE + INARG_COUNT;
340 final int NAME_LIMIT = INARG_LIMIT + convCount + 1;
341 final int RETURN_CONV = (!retConv ? -1 : NAME_LIMIT - 1);
342 final int OUT_CALL = (!retConv ? NAME_LIMIT : RETURN_CONV) - 1;
343 final int RESULT = (retVoid ? -1 : NAME_LIMIT - 1);
344
345 // Now build a LambdaForm.
346 MethodType lambdaType = srcType.basicType().invokerType();
347 Name[] names = arguments(NAME_LIMIT - INARG_LIMIT, lambdaType);
348
349 // Collect the arguments to the outgoing call, maybe with conversions:
350 final int OUTARG_BASE = 0; // target MH is Name.function, name Name.arguments[0]
351 Object[] outArgs = new Object[OUTARG_BASE + INARG_COUNT];
352
353 int nameCursor = INARG_LIMIT;
354 for (int i = 0; i < INARG_COUNT; i++) {
355 Object convSpec = convSpecs[i];
356 if (convSpec == null) {
357 // do nothing: difference is trivial
358 outArgs[OUTARG_BASE + i] = names[INARG_BASE + i];
359 continue;
360 }
361
362 Name conv;
363 if (convSpec instanceof Class) {
364 Class<?> convClass = (Class<?>) convSpec;
365 conv = new Name(getConstantHandle(MH_cast), convClass, names[INARG_BASE + i]);
366 } else {
367 MethodHandle fn = (MethodHandle) convSpec;
368 conv = new Name(fn, names[INARG_BASE + i]);
369 }
370 assert(names[nameCursor] == null);
371 names[nameCursor++] = conv;
372 assert(outArgs[OUTARG_BASE + i] == null);
373 outArgs[OUTARG_BASE + i] = conv;
374 }
375
376 // Build argument array for the call.
377 assert(nameCursor == OUT_CALL);
378 names[OUT_CALL] = new Name(target, outArgs);
379
380 Object convSpec = convSpecs[INARG_COUNT];
381 if (!retConv) {
382 assert(OUT_CALL == names.length-1);
383 } else {
384 Name conv;
385 if (convSpec == void.class) {
386 conv = new Name(LambdaForm.constantZero(BasicType.basicType(srcType.returnType())));
387 } else if (convSpec instanceof Class) {
388 Class<?> convClass = (Class<?>) convSpec;
389 conv = new Name(getConstantHandle(MH_cast), convClass, names[OUT_CALL]);
390 } else {
391 MethodHandle fn = (MethodHandle) convSpec;
392 if (fn.type().parameterCount() == 0)
393 conv = new Name(fn); // don't pass retval to void conversion
394 else
395 conv = new Name(fn, names[OUT_CALL]);
396 }
397 assert(names[RETURN_CONV] == null);
398 names[RETURN_CONV] = conv;
399 assert(RETURN_CONV == names.length-1);
400 }
401
402 LambdaForm form = new LambdaForm("convert", lambdaType.parameterCount(), names, RESULT);
403 return SimpleMethodHandle.make(srcType, form);
404 }
405
406 static Object[] computeValueConversions(MethodType srcType, MethodType dstType,
407 boolean strict, boolean monobox) {
408 final int INARG_COUNT = srcType.parameterCount();
409 Object[] convSpecs = new Object[INARG_COUNT+1];
410 for (int i = 0; i <= INARG_COUNT; i++) {
411 boolean isRet = (i == INARG_COUNT);
412 Class<?> src = isRet ? dstType.returnType() : srcType.parameterType(i);
413 Class<?> dst = isRet ? srcType.returnType() : dstType.parameterType(i);
414 if (!VerifyType.isNullConversion(src, dst, /*keepInterfaces=*/ strict)) {
415 convSpecs[i] = valueConversion(src, dst, strict, monobox);
416 }
417 }
418 return convSpecs;
419 }
420 static MethodHandle makePairwiseConvert(MethodHandle target, MethodType srcType,
421 boolean strict) {
422 return makePairwiseConvert(target, srcType, strict, /*monobox=*/ false);
423 }
424
425 /**
426 * Find a conversion function from the given source to the given destination.
427 * This conversion function will be used as a LF NamedFunction.
428 * Return a Class object if a simple cast is needed.
429 * Return void.class if void is involved.
430 */
431 static Object valueConversion(Class<?> src, Class<?> dst, boolean strict, boolean monobox) {
432 assert(!VerifyType.isNullConversion(src, dst, /*keepInterfaces=*/ strict)); // caller responsibility
433 if (dst == void.class)
434 return dst;
435 MethodHandle fn;
436 if (src.isPrimitive()) {
437 if (src == void.class) {
438 return void.class; // caller must recognize this specially
439 } else if (dst.isPrimitive()) {
440 // Examples: int->byte, byte->int, boolean->int (!strict)
441 fn = ValueConversions.convertPrimitive(src, dst);
442 } else {
443 // Examples: int->Integer, boolean->Object, float->Number
444 Wrapper wsrc = Wrapper.forPrimitiveType(src);
445 fn = ValueConversions.boxExact(wsrc);
446 assert(fn.type().parameterType(0) == wsrc.primitiveType());
447 assert(fn.type().returnType() == wsrc.wrapperType());
448 if (!VerifyType.isNullConversion(wsrc.wrapperType(), dst, strict)) {
449 // Corner case, such as int->Long, which will probably fail.
450 MethodType mt = MethodType.methodType(dst, src);
451 if (strict)
452 fn = fn.asType(mt);
453 else
454 fn = MethodHandleImpl.makePairwiseConvert(fn, mt, /*strict=*/ false);
455 }
456 }
457 } else if (dst.isPrimitive()) {
458 Wrapper wdst = Wrapper.forPrimitiveType(dst);
459 if (monobox || src == wdst.wrapperType()) {
460 // Use a strongly-typed unboxer, if possible.
461 fn = ValueConversions.unboxExact(wdst, strict);
462 } else {
463 // Examples: Object->int, Number->int, Comparable->int, Byte->int
464 // must include additional conversions
465 // src must be examined at runtime, to detect Byte, Character, etc.
466 fn = (strict
467 ? ValueConversions.unboxWiden(wdst)
468 : ValueConversions.unboxCast(wdst));
469 }
470 } else {
471 // Simple reference conversion.
472 // Note: Do not check for a class hierarchy relation
473 // between src and dst. In all cases a 'null' argument
474 // will pass the cast conversion.
475 return dst;
476 }
477 assert(fn.type().parameterCount() <= 1) : "pc"+Arrays.asList(src.getSimpleName(), dst.getSimpleName(), fn);
478 return fn;
479 }
480
481 static MethodHandle makeVarargsCollector(MethodHandle target, Class<?> arrayType) {
482 MethodType type = target.type();
483 int last = type.parameterCount() - 1;
484 if (type.parameterType(last) != arrayType)
485 target = target.asType(type.changeParameterType(last, arrayType));
486 target = target.asFixedArity(); // make sure this attribute is turned off
487 return new AsVarargsCollector(target, arrayType);
488 }
489
490 private static final class AsVarargsCollector extends DelegatingMethodHandle {
491 private final MethodHandle target;
492 private final Class<?> arrayType;
493 private @Stable MethodHandle asCollectorCache;
494
495 AsVarargsCollector(MethodHandle target, Class<?> arrayType) {
496 this(target.type(), target, arrayType);
497 }
498 AsVarargsCollector(MethodType type, MethodHandle target, Class<?> arrayType) {
499 super(type, target);
500 this.target = target;
501 this.arrayType = arrayType;
502 this.asCollectorCache = target.asCollector(arrayType, 0);
503 }
504
505 @Override
506 public boolean isVarargsCollector() {
507 return true;
508 }
509
510 @Override
511 protected MethodHandle getTarget() {
512 return target;
513 }
514
515 @Override
516 public MethodHandle asFixedArity() {
517 return target;
518 }
519
520 @Override
521 MethodHandle setVarargs(MemberName member) {
522 if (member.isVarargs()) return this;
523 return asFixedArity();
524 }
525
526 @Override
527 public MethodHandle asTypeUncached(MethodType newType) {
528 MethodType type = this.type();
529 int collectArg = type.parameterCount() - 1;
530 int newArity = newType.parameterCount();
531 if (newArity == collectArg+1 &&
532 type.parameterType(collectArg).isAssignableFrom(newType.parameterType(collectArg))) {
533 // if arity and trailing parameter are compatible, do normal thing
534 return asTypeCache = asFixedArity().asType(newType);
535 }
536 // check cache
537 MethodHandle acc = asCollectorCache;
538 if (acc != null && acc.type().parameterCount() == newArity)
539 return asTypeCache = acc.asType(newType);
540 // build and cache a collector
541 int arrayLength = newArity - collectArg;
542 MethodHandle collector;
543 try {
544 collector = asFixedArity().asCollector(arrayType, arrayLength);
545 assert(collector.type().parameterCount() == newArity) : "newArity="+newArity+" but collector="+collector;
546 } catch (IllegalArgumentException ex) {
547 throw new WrongMethodTypeException("cannot build collector", ex);
548 }
549 asCollectorCache = collector;
550 return asTypeCache = collector.asType(newType);
551 }
552
553 @Override
554 boolean viewAsTypeChecks(MethodType newType, boolean strict) {
555 super.viewAsTypeChecks(newType, true);
556 if (strict) return true;
557 // extra assertion for non-strict checks:
558 assert (type().lastParameterType().getComponentType()
559 .isAssignableFrom(
560 newType.lastParameterType().getComponentType()))
561 : Arrays.asList(this, newType);
562 return true;
563 }
564 }
565
566 /** Factory method: Spread selected argument. */
567 static MethodHandle makeSpreadArguments(MethodHandle target,
568 Class<?> spreadArgType, int spreadArgPos, int spreadArgCount) {
569 MethodType targetType = target.type();
570
571 for (int i = 0; i < spreadArgCount; i++) {
572 Class<?> arg = VerifyType.spreadArgElementType(spreadArgType, i);
573 if (arg == null) arg = Object.class;
574 targetType = targetType.changeParameterType(spreadArgPos + i, arg);
575 }
576 target = target.asType(targetType);
577
578 MethodType srcType = targetType
579 .replaceParameterTypes(spreadArgPos, spreadArgPos + spreadArgCount, spreadArgType);
580 // Now build a LambdaForm.
581 MethodType lambdaType = srcType.invokerType();
582 Name[] names = arguments(spreadArgCount + 2, lambdaType);
583 int nameCursor = lambdaType.parameterCount();
584 int[] indexes = new int[targetType.parameterCount()];
585
586 for (int i = 0, argIndex = 1; i < targetType.parameterCount() + 1; i++, argIndex++) {
587 Class<?> src = lambdaType.parameterType(i);
588 if (i == spreadArgPos) {
589 // Spread the array.
590 MethodHandle aload = MethodHandles.arrayElementGetter(spreadArgType);
591 Name array = names[argIndex];
592 names[nameCursor++] = new Name(NF_checkSpreadArgument, array, spreadArgCount);
593 for (int j = 0; j < spreadArgCount; i++, j++) {
594 indexes[i] = nameCursor;
595 names[nameCursor++] = new Name(aload, array, j);
596 }
597 } else if (i < indexes.length) {
598 indexes[i] = argIndex;
599 }
600 }
601 assert(nameCursor == names.length-1); // leave room for the final call
602
603 // Build argument array for the call.
604 Name[] targetArgs = new Name[targetType.parameterCount()];
605 for (int i = 0; i < targetType.parameterCount(); i++) {
606 int idx = indexes[i];
607 targetArgs[i] = names[idx];
608 }
609 names[names.length - 1] = new Name(target, (Object[]) targetArgs);
610
611 LambdaForm form = new LambdaForm("spread", lambdaType.parameterCount(), names);
612 return SimpleMethodHandle.make(srcType, form);
613 }
614
615 static void checkSpreadArgument(Object av, int n) {
616 if (av == null) {
617 if (n == 0) return;
618 } else if (av instanceof Object[]) {
619 int len = ((Object[])av).length;
620 if (len == n) return;
621 } else {
622 int len = java.lang.reflect.Array.getLength(av);
623 if (len == n) return;
624 }
625 // fall through to error:
626 throw newIllegalArgumentException("array is not of length "+n);
627 }
628
629 /** Factory method: Collect or filter selected argument(s). */
630 static MethodHandle makeCollectArguments(MethodHandle target,
631 MethodHandle collector, int collectArgPos, boolean retainOriginalArgs) {
632 MethodType targetType = target.type(); // (a..., c, [b...])=>r
633 MethodType collectorType = collector.type(); // (b...)=>c
634 int collectArgCount = collectorType.parameterCount();
635 Class<?> collectValType = collectorType.returnType();
636 int collectValCount = (collectValType == void.class ? 0 : 1);
637 MethodType srcType = targetType // (a..., [b...])=>r
638 .dropParameterTypes(collectArgPos, collectArgPos+collectValCount);
639 if (!retainOriginalArgs) { // (a..., b...)=>r
640 srcType = srcType.insertParameterTypes(collectArgPos, collectorType.parameterArray());
641 }
642 // in arglist: [0: ...keep1 | cpos: collect... | cpos+cacount: keep2... ]
643 // out arglist: [0: ...keep1 | cpos: collectVal? | cpos+cvcount: keep2... ]
644 // out(retain): [0: ...keep1 | cpos: cV? coll... | cpos+cvc+cac: keep2... ]
645
646 // Now build a LambdaForm.
647 MethodType lambdaType = srcType.invokerType();
648 Name[] names = arguments(2, lambdaType);
649 final int collectNamePos = names.length - 2;
650 final int targetNamePos = names.length - 1;
651
652 Name[] collectorArgs = Arrays.copyOfRange(names, 1 + collectArgPos, 1 + collectArgPos + collectArgCount);
653 names[collectNamePos] = new Name(collector, (Object[]) collectorArgs);
654
655 // Build argument array for the target.
656 // Incoming LF args to copy are: [ (mh) headArgs collectArgs tailArgs ].
657 // Output argument array is [ headArgs (collectVal)? (collectArgs)? tailArgs ].
658 Name[] targetArgs = new Name[targetType.parameterCount()];
659 int inputArgPos = 1; // incoming LF args to copy to target
660 int targetArgPos = 0; // fill pointer for targetArgs
661 int chunk = collectArgPos; // |headArgs|
662 System.arraycopy(names, inputArgPos, targetArgs, targetArgPos, chunk);
663 inputArgPos += chunk;
664 targetArgPos += chunk;
665 if (collectValType != void.class) {
666 targetArgs[targetArgPos++] = names[collectNamePos];
667 }
668 chunk = collectArgCount;
669 if (retainOriginalArgs) {
670 System.arraycopy(names, inputArgPos, targetArgs, targetArgPos, chunk);
671 targetArgPos += chunk; // optionally pass on the collected chunk
672 }
673 inputArgPos += chunk;
674 chunk = targetArgs.length - targetArgPos; // all the rest
675 System.arraycopy(names, inputArgPos, targetArgs, targetArgPos, chunk);
676 assert(inputArgPos + chunk == collectNamePos); // use of rest of input args also
677 names[targetNamePos] = new Name(target, (Object[]) targetArgs);
678
679 LambdaForm form = new LambdaForm("collect", lambdaType.parameterCount(), names);
680 return SimpleMethodHandle.make(srcType, form);
681 }
682
683 @LambdaForm.Hidden
684 static
685 MethodHandle selectAlternative(boolean testResult, MethodHandle target, MethodHandle fallback) {
686 if (testResult) {
687 return target;
688 } else {
689 return fallback;
690 }
691 }
692
693 // Intrinsified by C2. Counters are used during parsing to calculate branch frequencies.
694 @LambdaForm.Hidden
695 @jdk.internal.HotSpotIntrinsicCandidate
696 static
697 boolean profileBoolean(boolean result, int[] counters) {
698 // Profile is int[2] where [0] and [1] correspond to false and true occurrences respectively.
699 int idx = result ? 1 : 0;
700 try {
701 counters[idx] = Math.addExact(counters[idx], 1);
702 } catch (ArithmeticException e) {
703 // Avoid continuous overflow by halving the problematic count.
704 counters[idx] = counters[idx] / 2;
705 }
706 return result;
707 }
708
709 // Intrinsified by C2. Returns true if obj is a compile-time constant.
710 @LambdaForm.Hidden
711 @jdk.internal.HotSpotIntrinsicCandidate
712 static
713 boolean isCompileConstant(Object obj) {
714 return false;
715 }
716
717 static
718 MethodHandle makeGuardWithTest(MethodHandle test,
719 MethodHandle target,
720 MethodHandle fallback) {
721 MethodType type = target.type();
722 assert(test.type().equals(type.changeReturnType(boolean.class)) && fallback.type().equals(type));
723 MethodType basicType = type.basicType();
724 LambdaForm form = makeGuardWithTestForm(basicType);
725 BoundMethodHandle mh;
726 try {
727 if (PROFILE_GWT) {
728 int[] counts = new int[2];
729 mh = (BoundMethodHandle)
730 BoundMethodHandle.speciesData_LLLL().constructor().invokeBasic(type, form,
731 (Object) test, (Object) profile(target), (Object) profile(fallback), counts);
732 } else {
733 mh = (BoundMethodHandle)
734 BoundMethodHandle.speciesData_LLL().constructor().invokeBasic(type, form,
735 (Object) test, (Object) profile(target), (Object) profile(fallback));
736 }
737 } catch (Throwable ex) {
738 throw uncaughtException(ex);
739 }
740 assert(mh.type() == type);
741 return mh;
742 }
743
744
745 static
746 MethodHandle profile(MethodHandle target) {
747 if (DONT_INLINE_THRESHOLD >= 0) {
748 return makeBlockInliningWrapper(target);
749 } else {
750 return target;
751 }
752 }
753
754 /**
755 * Block inlining during JIT-compilation of a target method handle if it hasn't been invoked enough times.
756 * Corresponding LambdaForm has @DontInline when compiled into bytecode.
757 */
758 static
759 MethodHandle makeBlockInliningWrapper(MethodHandle target) {
760 LambdaForm lform;
761 if (DONT_INLINE_THRESHOLD > 0) {
762 lform = Makers.PRODUCE_BLOCK_INLINING_FORM.apply(target);
763 } else {
764 lform = Makers.PRODUCE_REINVOKER_FORM.apply(target);
765 }
766 return new CountingWrapper(target, lform,
767 Makers.PRODUCE_BLOCK_INLINING_FORM, Makers.PRODUCE_REINVOKER_FORM,
768 DONT_INLINE_THRESHOLD);
769 }
770
771 private final static class Makers {
772 /** Constructs reinvoker lambda form which block inlining during JIT-compilation for a particular method handle */
773 static final Function<MethodHandle, LambdaForm> PRODUCE_BLOCK_INLINING_FORM = new Function<MethodHandle, LambdaForm>() {
774 @Override
775 public LambdaForm apply(MethodHandle target) {
776 return DelegatingMethodHandle.makeReinvokerForm(target,
777 MethodTypeForm.LF_DELEGATE_BLOCK_INLINING, CountingWrapper.class, "reinvoker.dontInline", false,
778 DelegatingMethodHandle.NF_getTarget, CountingWrapper.NF_maybeStopCounting);
779 }
780 };
781
782 /** Constructs simple reinvoker lambda form for a particular method handle */
783 static final Function<MethodHandle, LambdaForm> PRODUCE_REINVOKER_FORM = new Function<MethodHandle, LambdaForm>() {
784 @Override
785 public LambdaForm apply(MethodHandle target) {
786 return DelegatingMethodHandle.makeReinvokerForm(target,
787 MethodTypeForm.LF_DELEGATE, DelegatingMethodHandle.class, DelegatingMethodHandle.NF_getTarget);
788 }
789 };
790
791 /** Maker of type-polymorphic varargs */
792 static final ClassValue<MethodHandle[]> TYPED_COLLECTORS = new ClassValue<MethodHandle[]>() {
793 @Override
794 protected MethodHandle[] computeValue(Class<?> type) {
795 return new MethodHandle[MAX_JVM_ARITY + 1];
796 }
797 };
798 }
799
800 /**
801 * Counting method handle. It has 2 states: counting and non-counting.
802 * It is in counting state for the first n invocations and then transitions to non-counting state.
803 * Behavior in counting and non-counting states is determined by lambda forms produced by
804 * countingFormProducer & nonCountingFormProducer respectively.
805 */
806 static class CountingWrapper extends DelegatingMethodHandle {
807 private final MethodHandle target;
808 private int count;
809 private Function<MethodHandle, LambdaForm> countingFormProducer;
810 private Function<MethodHandle, LambdaForm> nonCountingFormProducer;
811 private volatile boolean isCounting;
812
813 private CountingWrapper(MethodHandle target, LambdaForm lform,
814 Function<MethodHandle, LambdaForm> countingFromProducer,
815 Function<MethodHandle, LambdaForm> nonCountingFormProducer,
816 int count) {
817 super(target.type(), lform);
818 this.target = target;
819 this.count = count;
820 this.countingFormProducer = countingFromProducer;
821 this.nonCountingFormProducer = nonCountingFormProducer;
822 this.isCounting = (count > 0);
823 }
824
825 @Hidden
826 @Override
827 protected MethodHandle getTarget() {
828 return target;
829 }
830
831 @Override
832 public MethodHandle asTypeUncached(MethodType newType) {
833 MethodHandle newTarget = target.asType(newType);
834 MethodHandle wrapper;
835 if (isCounting) {
836 LambdaForm lform;
837 lform = countingFormProducer.apply(newTarget);
838 wrapper = new CountingWrapper(newTarget, lform, countingFormProducer, nonCountingFormProducer, DONT_INLINE_THRESHOLD);
839 } else {
840 wrapper = newTarget; // no need for a counting wrapper anymore
841 }
842 return (asTypeCache = wrapper);
843 }
844
845 // Customize target if counting happens for too long.
846 private int invocations = CUSTOMIZE_THRESHOLD;
847 private void maybeCustomizeTarget() {
848 int c = invocations;
849 if (c >= 0) {
850 if (c == 1) {
851 target.customize();
852 }
853 invocations = c - 1;
854 }
855 }
856
857 boolean countDown() {
858 int c = count;
859 maybeCustomizeTarget();
860 if (c <= 1) {
861 // Try to limit number of updates. MethodHandle.updateForm() doesn't guarantee LF update visibility.
862 if (isCounting) {
863 isCounting = false;
864 return true;
865 } else {
866 return false;
867 }
868 } else {
869 count = c - 1;
870 return false;
871 }
872 }
873
874 @Hidden
875 static void maybeStopCounting(Object o1) {
876 CountingWrapper wrapper = (CountingWrapper) o1;
877 if (wrapper.countDown()) {
878 // Reached invocation threshold. Replace counting behavior with a non-counting one.
879 LambdaForm lform = wrapper.nonCountingFormProducer.apply(wrapper.target);
880 lform.compileToBytecode(); // speed up warmup by avoiding LF interpretation again after transition
881 wrapper.updateForm(lform);
882 }
883 }
884
885 static final NamedFunction NF_maybeStopCounting;
886 static {
887 Class<?> THIS_CLASS = CountingWrapper.class;
888 try {
889 NF_maybeStopCounting = new NamedFunction(THIS_CLASS.getDeclaredMethod("maybeStopCounting", Object.class));
890 } catch (ReflectiveOperationException ex) {
891 throw newInternalError(ex);
892 }
893 }
894 }
895
896 static
897 LambdaForm makeGuardWithTestForm(MethodType basicType) {
898 LambdaForm lform = basicType.form().cachedLambdaForm(MethodTypeForm.LF_GWT);
899 if (lform != null) return lform;
900 final int THIS_MH = 0; // the BMH_LLL
901 final int ARG_BASE = 1; // start of incoming arguments
902 final int ARG_LIMIT = ARG_BASE + basicType.parameterCount();
903 int nameCursor = ARG_LIMIT;
904 final int GET_TEST = nameCursor++;
905 final int GET_TARGET = nameCursor++;
906 final int GET_FALLBACK = nameCursor++;
907 final int GET_COUNTERS = PROFILE_GWT ? nameCursor++ : -1;
908 final int CALL_TEST = nameCursor++;
909 final int PROFILE = (GET_COUNTERS != -1) ? nameCursor++ : -1;
910 final int TEST = nameCursor-1; // previous statement: either PROFILE or CALL_TEST
911 final int SELECT_ALT = nameCursor++;
912 final int CALL_TARGET = nameCursor++;
913 assert(CALL_TARGET == SELECT_ALT+1); // must be true to trigger IBG.emitSelectAlternative
914
915 MethodType lambdaType = basicType.invokerType();
916 Name[] names = arguments(nameCursor - ARG_LIMIT, lambdaType);
917
918 BoundMethodHandle.SpeciesData data =
919 (GET_COUNTERS != -1) ? BoundMethodHandle.speciesData_LLLL()
920 : BoundMethodHandle.speciesData_LLL();
921 names[THIS_MH] = names[THIS_MH].withConstraint(data);
922 names[GET_TEST] = new Name(data.getterFunction(0), names[THIS_MH]);
923 names[GET_TARGET] = new Name(data.getterFunction(1), names[THIS_MH]);
924 names[GET_FALLBACK] = new Name(data.getterFunction(2), names[THIS_MH]);
925 if (GET_COUNTERS != -1) {
926 names[GET_COUNTERS] = new Name(data.getterFunction(3), names[THIS_MH]);
927 }
928 Object[] invokeArgs = Arrays.copyOfRange(names, 0, ARG_LIMIT, Object[].class);
929
930 // call test
931 MethodType testType = basicType.changeReturnType(boolean.class).basicType();
932 invokeArgs[0] = names[GET_TEST];
933 names[CALL_TEST] = new Name(testType, invokeArgs);
934
935 // profile branch
936 if (PROFILE != -1) {
937 names[PROFILE] = new Name(NF_profileBoolean, names[CALL_TEST], names[GET_COUNTERS]);
938 }
939 // call selectAlternative
940 names[SELECT_ALT] = new Name(getConstantHandle(MH_selectAlternative), names[TEST], names[GET_TARGET], names[GET_FALLBACK]);
941
942 // call target or fallback
943 invokeArgs[0] = names[SELECT_ALT];
944 names[CALL_TARGET] = new Name(basicType, invokeArgs);
945
946 lform = new LambdaForm("guard", lambdaType.parameterCount(), names, /*forceInline=*/true);
947
948 return basicType.form().setCachedLambdaForm(MethodTypeForm.LF_GWT, lform);
949 }
950
951 /**
952 * The LambdaForm shape for catchException combinator is the following:
953 * <blockquote><pre>{@code
954 * guardWithCatch=Lambda(a0:L,a1:L,a2:L)=>{
955 * t3:L=BoundMethodHandle$Species_LLLLL.argL0(a0:L);
956 * t4:L=BoundMethodHandle$Species_LLLLL.argL1(a0:L);
957 * t5:L=BoundMethodHandle$Species_LLLLL.argL2(a0:L);
958 * t6:L=BoundMethodHandle$Species_LLLLL.argL3(a0:L);
959 * t7:L=BoundMethodHandle$Species_LLLLL.argL4(a0:L);
960 * t8:L=MethodHandle.invokeBasic(t6:L,a1:L,a2:L);
961 * t9:L=MethodHandleImpl.guardWithCatch(t3:L,t4:L,t5:L,t8:L);
962 * t10:I=MethodHandle.invokeBasic(t7:L,t9:L);t10:I}
963 * }</pre></blockquote>
964 *
965 * argL0 and argL2 are target and catcher method handles. argL1 is exception class.
966 * argL3 and argL4 are auxiliary method handles: argL3 boxes arguments and wraps them into Object[]
967 * (ValueConversions.array()) and argL4 unboxes result if necessary (ValueConversions.unbox()).
968 *
969 * Having t8 and t10 passed outside and not hardcoded into a lambda form allows to share lambda forms
970 * among catchException combinators with the same basic type.
971 */
972 private static LambdaForm makeGuardWithCatchForm(MethodType basicType) {
973 MethodType lambdaType = basicType.invokerType();
974
975 LambdaForm lform = basicType.form().cachedLambdaForm(MethodTypeForm.LF_GWC);
976 if (lform != null) {
977 return lform;
978 }
979 final int THIS_MH = 0; // the BMH_LLLLL
980 final int ARG_BASE = 1; // start of incoming arguments
981 final int ARG_LIMIT = ARG_BASE + basicType.parameterCount();
982
983 int nameCursor = ARG_LIMIT;
984 final int GET_TARGET = nameCursor++;
985 final int GET_CLASS = nameCursor++;
986 final int GET_CATCHER = nameCursor++;
987 final int GET_COLLECT_ARGS = nameCursor++;
988 final int GET_UNBOX_RESULT = nameCursor++;
989 final int BOXED_ARGS = nameCursor++;
990 final int TRY_CATCH = nameCursor++;
991 final int UNBOX_RESULT = nameCursor++;
992
993 Name[] names = arguments(nameCursor - ARG_LIMIT, lambdaType);
994
995 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLLLL();
996 names[THIS_MH] = names[THIS_MH].withConstraint(data);
997 names[GET_TARGET] = new Name(data.getterFunction(0), names[THIS_MH]);
998 names[GET_CLASS] = new Name(data.getterFunction(1), names[THIS_MH]);
999 names[GET_CATCHER] = new Name(data.getterFunction(2), names[THIS_MH]);
1000 names[GET_COLLECT_ARGS] = new Name(data.getterFunction(3), names[THIS_MH]);
1001 names[GET_UNBOX_RESULT] = new Name(data.getterFunction(4), names[THIS_MH]);
1002
1003 // FIXME: rework argument boxing/result unboxing logic for LF interpretation
1004
1005 // t_{i}:L=MethodHandle.invokeBasic(collectArgs:L,a1:L,...);
1006 MethodType collectArgsType = basicType.changeReturnType(Object.class);
1007 MethodHandle invokeBasic = MethodHandles.basicInvoker(collectArgsType);
1008 Object[] args = new Object[invokeBasic.type().parameterCount()];
1009 args[0] = names[GET_COLLECT_ARGS];
1010 System.arraycopy(names, ARG_BASE, args, 1, ARG_LIMIT-ARG_BASE);
1011 names[BOXED_ARGS] = new Name(makeIntrinsic(invokeBasic, Intrinsic.GUARD_WITH_CATCH), args);
1012
1013 // t_{i+1}:L=MethodHandleImpl.guardWithCatch(target:L,exType:L,catcher:L,t_{i}:L);
1014 Object[] gwcArgs = new Object[] {names[GET_TARGET], names[GET_CLASS], names[GET_CATCHER], names[BOXED_ARGS]};
1015 names[TRY_CATCH] = new Name(NF_guardWithCatch, gwcArgs);
1016
1017 // t_{i+2}:I=MethodHandle.invokeBasic(unbox:L,t_{i+1}:L);
1018 MethodHandle invokeBasicUnbox = MethodHandles.basicInvoker(MethodType.methodType(basicType.rtype(), Object.class));
1019 Object[] unboxArgs = new Object[] {names[GET_UNBOX_RESULT], names[TRY_CATCH]};
1020 names[UNBOX_RESULT] = new Name(invokeBasicUnbox, unboxArgs);
1021
1022 lform = new LambdaForm("guardWithCatch", lambdaType.parameterCount(), names);
1023
1024 return basicType.form().setCachedLambdaForm(MethodTypeForm.LF_GWC, lform);
1025 }
1026
1027 static
1028 MethodHandle makeGuardWithCatch(MethodHandle target,
1029 Class<? extends Throwable> exType,
1030 MethodHandle catcher) {
1031 MethodType type = target.type();
1032 LambdaForm form = makeGuardWithCatchForm(type.basicType());
1033
1034 // Prepare auxiliary method handles used during LambdaForm interpretation.
1035 // Box arguments and wrap them into Object[]: ValueConversions.array().
1036 MethodType varargsType = type.changeReturnType(Object[].class);
1037 MethodHandle collectArgs = varargsArray(type.parameterCount()).asType(varargsType);
1038 MethodHandle unboxResult = unboxResultHandle(type.returnType());
1039
1040 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLLLL();
1041 BoundMethodHandle mh;
1042 try {
1043 mh = (BoundMethodHandle) data.constructor().invokeBasic(type, form, (Object) target, (Object) exType,
1044 (Object) catcher, (Object) collectArgs, (Object) unboxResult);
1045 } catch (Throwable ex) {
1046 throw uncaughtException(ex);
1047 }
1048 assert(mh.type() == type);
1049 return mh;
1050 }
1051
1052 /**
1053 * Intrinsified during LambdaForm compilation
1054 * (see {@link InvokerBytecodeGenerator#emitGuardWithCatch emitGuardWithCatch}).
1055 */
1056 @LambdaForm.Hidden
1057 static Object guardWithCatch(MethodHandle target, Class<? extends Throwable> exType, MethodHandle catcher,
1058 Object... av) throws Throwable {
1059 // Use asFixedArity() to avoid unnecessary boxing of last argument for VarargsCollector case.
1060 try {
1061 return target.asFixedArity().invokeWithArguments(av);
1062 } catch (Throwable t) {
1063 if (!exType.isInstance(t)) throw t;
1064 return catcher.asFixedArity().invokeWithArguments(prepend(av, t));
1065 }
1066 }
1067
1068 /** Prepend elements to an array. */
1069 @LambdaForm.Hidden
1070 private static Object[] prepend(Object[] array, Object... elems) {
1071 int nArray = array.length;
1072 int nElems = elems.length;
1073 Object[] newArray = new Object[nArray + nElems];
1074 System.arraycopy(elems, 0, newArray, 0, nElems);
1075 System.arraycopy(array, 0, newArray, nElems, nArray);
1076 return newArray;
1077 }
1078
1079 static
1080 MethodHandle throwException(MethodType type) {
1081 assert(Throwable.class.isAssignableFrom(type.parameterType(0)));
1082 int arity = type.parameterCount();
1083 if (arity > 1) {
1084 MethodHandle mh = throwException(type.dropParameterTypes(1, arity));
1085 mh = MethodHandles.dropArguments(mh, 1, Arrays.copyOfRange(type.parameterArray(), 1, arity));
1086 return mh;
1087 }
1088 return makePairwiseConvert(NF_throwException.resolvedHandle(), type, false, true);
1089 }
1090
1091 static <T extends Throwable> Empty throwException(T t) throws T { throw t; }
1092
1093 static MethodHandle[] FAKE_METHOD_HANDLE_INVOKE = new MethodHandle[2];
1094 static MethodHandle fakeMethodHandleInvoke(MemberName method) {
1095 int idx;
1096 assert(method.isMethodHandleInvoke());
1097 switch (method.getName()) {
1098 case "invoke": idx = 0; break;
1099 case "invokeExact": idx = 1; break;
1100 default: throw new InternalError(method.getName());
1101 }
1102 MethodHandle mh = FAKE_METHOD_HANDLE_INVOKE[idx];
1103 if (mh != null) return mh;
1104 MethodType type = MethodType.methodType(Object.class, UnsupportedOperationException.class,
1105 MethodHandle.class, Object[].class);
1106 mh = throwException(type);
1107 mh = mh.bindTo(new UnsupportedOperationException("cannot reflectively invoke MethodHandle"));
1108 if (!method.getInvocationType().equals(mh.type()))
1109 throw new InternalError(method.toString());
1110 mh = mh.withInternalMemberName(method, false);
1111 mh = mh.withVarargs(true);
1112 assert(method.isVarargs());
1113 FAKE_METHOD_HANDLE_INVOKE[idx] = mh;
1114 return mh;
1115 }
1116 static MethodHandle fakeVarHandleInvoke(MemberName method) {
1117 // TODO caching, is it necessary?
1118 MethodType type = MethodType.methodType(method.getReturnType(), UnsupportedOperationException.class,
1119 VarHandle.class, Object[].class);
1120 MethodHandle mh = throwException(type);
1121 mh = mh.bindTo(new UnsupportedOperationException("cannot reflectively invoke VarHandle"));
1122 if (!method.getInvocationType().equals(mh.type()))
1123 throw new InternalError(method.toString());
1124 mh = mh.withInternalMemberName(method, false);
1125 mh = mh.asVarargsCollector(Object[].class);
1126 assert(method.isVarargs());
1127 return mh;
1128 }
1129
1130 /**
1131 * Create an alias for the method handle which, when called,
1132 * appears to be called from the same class loader and protection domain
1133 * as hostClass.
1134 * This is an expensive no-op unless the method which is called
1135 * is sensitive to its caller. A small number of system methods
1136 * are in this category, including Class.forName and Method.invoke.
1137 */
1138 static
1139 MethodHandle bindCaller(MethodHandle mh, Class<?> hostClass) {
1140 return BindCaller.bindCaller(mh, hostClass);
1141 }
1142
1143 // Put the whole mess into its own nested class.
1144 // That way we can lazily load the code and set up the constants.
1145 private static class BindCaller {
1146 private static MethodType INVOKER_MT = MethodType.methodType(Object.class, MethodHandle.class, Object[].class);
1147
1148 static
1149 MethodHandle bindCaller(MethodHandle mh, Class<?> hostClass) {
1150 // Code in the the boot layer should now be careful while creating method handles or
1151 // functional interface instances created from method references to @CallerSensitive methods,
1152 // it needs to be ensured the handles or interface instances are kept safe and are not passed
1153 // from the boot layer to untrusted code.
1154 if (hostClass == null
1155 || (hostClass.isArray() ||
1156 hostClass.isPrimitive() ||
1157 hostClass.getName().startsWith("java.lang.invoke."))) {
1158 throw new InternalError(); // does not happen, and should not anyway
1159 }
1160 // For simplicity, convert mh to a varargs-like method.
1161 MethodHandle vamh = prepareForInvoker(mh);
1162 // Cache the result of makeInjectedInvoker once per argument class.
1163 MethodHandle bccInvoker = CV_makeInjectedInvoker.get(hostClass);
1164 return restoreToType(bccInvoker.bindTo(vamh), mh, hostClass);
1165 }
1166
1167 private static MethodHandle makeInjectedInvoker(Class<?> hostClass) {
1168 try {
1169 Class<?> invokerClass = UNSAFE.defineAnonymousClass(hostClass, INJECTED_INVOKER_TEMPLATE, null);
1170 assert checkInjectedInvoker(hostClass, invokerClass);
1171 return IMPL_LOOKUP.findStatic(invokerClass, "invoke_V", INVOKER_MT);
1172 } catch (ReflectiveOperationException ex) {
1173 throw uncaughtException(ex);
1174 }
1175 }
1176
1177 private static ClassValue<MethodHandle> CV_makeInjectedInvoker = new ClassValue<MethodHandle>() {
1178 @Override protected MethodHandle computeValue(Class<?> hostClass) {
1179 return makeInjectedInvoker(hostClass);
1180 }
1181 };
1182
1183 // Adapt mh so that it can be called directly from an injected invoker:
1184 private static MethodHandle prepareForInvoker(MethodHandle mh) {
1185 mh = mh.asFixedArity();
1186 MethodType mt = mh.type();
1187 int arity = mt.parameterCount();
1188 MethodHandle vamh = mh.asType(mt.generic());
1189 vamh.internalForm().compileToBytecode(); // eliminate LFI stack frames
1190 vamh = vamh.asSpreader(Object[].class, arity);
1191 vamh.internalForm().compileToBytecode(); // eliminate LFI stack frames
1192 return vamh;
1193 }
1194
1195 // Undo the adapter effect of prepareForInvoker:
1196 private static MethodHandle restoreToType(MethodHandle vamh,
1197 MethodHandle original,
1198 Class<?> hostClass) {
1199 MethodType type = original.type();
1200 MethodHandle mh = vamh.asCollector(Object[].class, type.parameterCount());
1201 MemberName member = original.internalMemberName();
1202 mh = mh.asType(type);
1203 mh = new WrappedMember(mh, type, member, original.isInvokeSpecial(), hostClass);
1204 return mh;
1205 }
1206
1207 private static boolean checkInjectedInvoker(Class<?> hostClass, Class<?> invokerClass) {
1208 assert (hostClass.getClassLoader() == invokerClass.getClassLoader()) : hostClass.getName()+" (CL)";
1209 try {
1210 assert (hostClass.getProtectionDomain() == invokerClass.getProtectionDomain()) : hostClass.getName()+" (PD)";
1211 } catch (SecurityException ex) {
1212 // Self-check was blocked by security manager. This is OK.
1213 }
1214 try {
1215 // Test the invoker to ensure that it really injects into the right place.
1216 MethodHandle invoker = IMPL_LOOKUP.findStatic(invokerClass, "invoke_V", INVOKER_MT);
1217 MethodHandle vamh = prepareForInvoker(MH_checkCallerClass);
1218 return (boolean)invoker.invoke(vamh, new Object[]{ invokerClass });
1219 } catch (Throwable ex) {
1220 throw new InternalError(ex);
1221 }
1222 }
1223
1224 private static final MethodHandle MH_checkCallerClass;
1225 static {
1226 final Class<?> THIS_CLASS = BindCaller.class;
1227 assert(checkCallerClass(THIS_CLASS));
1228 try {
1229 MH_checkCallerClass = IMPL_LOOKUP
1230 .findStatic(THIS_CLASS, "checkCallerClass",
1231 MethodType.methodType(boolean.class, Class.class));
1232 assert((boolean) MH_checkCallerClass.invokeExact(THIS_CLASS));
1233 } catch (Throwable ex) {
1234 throw new InternalError(ex);
1235 }
1236 }
1237
1238 @CallerSensitive
1239 @ForceInline // to ensure Reflection.getCallerClass optimization
1240 private static boolean checkCallerClass(Class<?> expected) {
1241 // This method is called via MH_checkCallerClass and so it's correct to ask for the immediate caller here.
1242 Class<?> actual = Reflection.getCallerClass();
1243 if (actual != expected)
1244 throw new InternalError("found " + actual.getName() + ", expected " + expected.getName());
1245 return true;
1246 }
1247
1248 private static final byte[] INJECTED_INVOKER_TEMPLATE = generateInvokerTemplate();
1249
1250 /** Produces byte code for a class that is used as an injected invoker. */
1251 private static byte[] generateInvokerTemplate() {
1252 ClassWriter cw = new ClassWriter(0);
1253
1254 // private static class InjectedInvoker {
1255 // @Hidden
1256 // static Object invoke_V(MethodHandle vamh, Object[] args) throws Throwable {
1257 // return vamh.invokeExact(args);
1258 // }
1259 // }
1260 cw.visit(52, ACC_PRIVATE | ACC_SUPER, "InjectedInvoker", null, "java/lang/Object", null);
1261
1262 MethodVisitor mv = cw.visitMethod(ACC_STATIC, "invoke_V",
1263 "(Ljava/lang/invoke/MethodHandle;[Ljava/lang/Object;)Ljava/lang/Object;",
1264 null, null);
1265
1266 // Suppress invoker method in stack traces.
1267 AnnotationVisitor av0 = mv.visitAnnotation("Ljava/lang/invoke/LambdaForm$Hidden;", true);
1268 av0.visitEnd();
1269
1270 mv.visitCode();
1271 mv.visitVarInsn(ALOAD, 0);
1272 mv.visitVarInsn(ALOAD, 1);
1273 mv.visitMethodInsn(INVOKEVIRTUAL, "java/lang/invoke/MethodHandle", "invokeExact",
1274 "([Ljava/lang/Object;)Ljava/lang/Object;", false);
1275 mv.visitInsn(ARETURN);
1276 mv.visitMaxs(2, 2);
1277 mv.visitEnd();
1278
1279 cw.visitEnd();
1280 return cw.toByteArray();
1281 }
1282 }
1283
1284 /** This subclass allows a wrapped method handle to be re-associated with an arbitrary member name. */
1285 private static final class WrappedMember extends DelegatingMethodHandle {
1286 private final MethodHandle target;
1287 private final MemberName member;
1288 private final Class<?> callerClass;
1289 private final boolean isInvokeSpecial;
1290
1291 private WrappedMember(MethodHandle target, MethodType type,
1292 MemberName member, boolean isInvokeSpecial,
1293 Class<?> callerClass) {
1294 super(type, target);
1295 this.target = target;
1296 this.member = member;
1297 this.callerClass = callerClass;
1298 this.isInvokeSpecial = isInvokeSpecial;
1299 }
1300
1301 @Override
1302 MemberName internalMemberName() {
1303 return member;
1304 }
1305 @Override
1306 Class<?> internalCallerClass() {
1307 return callerClass;
1308 }
1309 @Override
1310 boolean isInvokeSpecial() {
1311 return isInvokeSpecial;
1312 }
1313 @Override
1314 protected MethodHandle getTarget() {
1315 return target;
1316 }
1317 @Override
1318 public MethodHandle asTypeUncached(MethodType newType) {
1319 // This MH is an alias for target, except for the MemberName
1320 // Drop the MemberName if there is any conversion.
1321 return asTypeCache = target.asType(newType);
1322 }
1323 }
1324
1325 static MethodHandle makeWrappedMember(MethodHandle target, MemberName member, boolean isInvokeSpecial) {
1326 if (member.equals(target.internalMemberName()) && isInvokeSpecial == target.isInvokeSpecial())
1327 return target;
1328 return new WrappedMember(target, target.type(), member, isInvokeSpecial, null);
1329 }
1330
1331 /** Intrinsic IDs */
1332 /*non-public*/
1333 enum Intrinsic {
1334 SELECT_ALTERNATIVE,
1335 GUARD_WITH_CATCH,
1336 TRY_FINALLY,
1337 LOOP,
1338 NEW_ARRAY,
1339 ARRAY_LOAD,
1340 ARRAY_STORE,
1341 ARRAY_LENGTH,
1342 IDENTITY,
1343 ZERO,
1344 NONE // no intrinsic associated
1345 }
1346
1347 /** Mark arbitrary method handle as intrinsic.
1348 * InvokerBytecodeGenerator uses this info to produce more efficient bytecode shape. */
1349 static final class IntrinsicMethodHandle extends DelegatingMethodHandle {
1350 private final MethodHandle target;
1351 private final Intrinsic intrinsicName;
1352
1353 IntrinsicMethodHandle(MethodHandle target, Intrinsic intrinsicName) {
1354 super(target.type(), target);
1355 this.target = target;
1356 this.intrinsicName = intrinsicName;
1357 }
1358
1359 @Override
1360 protected MethodHandle getTarget() {
1361 return target;
1362 }
1363
1364 @Override
1365 Intrinsic intrinsicName() {
1366 return intrinsicName;
1367 }
1368
1369 @Override
1370 public MethodHandle asTypeUncached(MethodType newType) {
1371 // This MH is an alias for target, except for the intrinsic name
1372 // Drop the name if there is any conversion.
1373 return asTypeCache = target.asType(newType);
1374 }
1375
1376 @Override
1377 String internalProperties() {
1378 return super.internalProperties() +
1379 "\n& Intrinsic="+intrinsicName;
1380 }
1381
1382 @Override
1383 public MethodHandle asCollector(Class<?> arrayType, int arrayLength) {
1384 if (intrinsicName == Intrinsic.IDENTITY) {
1385 MethodType resultType = type().asCollectorType(arrayType, type().parameterCount() - 1, arrayLength);
1386 MethodHandle newArray = MethodHandleImpl.varargsArray(arrayType, arrayLength);
1387 return newArray.asType(resultType);
1388 }
1389 return super.asCollector(arrayType, arrayLength);
1390 }
1391 }
1392
1393 static MethodHandle makeIntrinsic(MethodHandle target, Intrinsic intrinsicName) {
1394 if (intrinsicName == target.intrinsicName())
1395 return target;
1396 return new IntrinsicMethodHandle(target, intrinsicName);
1397 }
1398
1399 static MethodHandle makeIntrinsic(MethodType type, LambdaForm form, Intrinsic intrinsicName) {
1400 return new IntrinsicMethodHandle(SimpleMethodHandle.make(type, form), intrinsicName);
1401 }
1402
1403 /// Collection of multiple arguments.
1404
1405 private static MethodHandle findCollector(String name, int nargs, Class<?> rtype, Class<?>... ptypes) {
1406 MethodType type = MethodType.genericMethodType(nargs)
1407 .changeReturnType(rtype)
1408 .insertParameterTypes(0, ptypes);
1409 try {
1410 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, name, type);
1411 } catch (ReflectiveOperationException ex) {
1412 return null;
1413 }
1414 }
1415
1416 private static final Object[] NO_ARGS_ARRAY = {};
1417 private static Object[] makeArray(Object... args) { return args; }
1418 private static Object[] array() { return NO_ARGS_ARRAY; }
1419 private static Object[] array(Object a0)
1420 { return makeArray(a0); }
1421 private static Object[] array(Object a0, Object a1)
1422 { return makeArray(a0, a1); }
1423 private static Object[] array(Object a0, Object a1, Object a2)
1424 { return makeArray(a0, a1, a2); }
1425 private static Object[] array(Object a0, Object a1, Object a2, Object a3)
1426 { return makeArray(a0, a1, a2, a3); }
1427 private static Object[] array(Object a0, Object a1, Object a2, Object a3,
1428 Object a4)
1429 { return makeArray(a0, a1, a2, a3, a4); }
1430 private static Object[] array(Object a0, Object a1, Object a2, Object a3,
1431 Object a4, Object a5)
1432 { return makeArray(a0, a1, a2, a3, a4, a5); }
1433 private static Object[] array(Object a0, Object a1, Object a2, Object a3,
1434 Object a4, Object a5, Object a6)
1435 { return makeArray(a0, a1, a2, a3, a4, a5, a6); }
1436 private static Object[] array(Object a0, Object a1, Object a2, Object a3,
1437 Object a4, Object a5, Object a6, Object a7)
1438 { return makeArray(a0, a1, a2, a3, a4, a5, a6, a7); }
1439 private static Object[] array(Object a0, Object a1, Object a2, Object a3,
1440 Object a4, Object a5, Object a6, Object a7,
1441 Object a8)
1442 { return makeArray(a0, a1, a2, a3, a4, a5, a6, a7, a8); }
1443 private static Object[] array(Object a0, Object a1, Object a2, Object a3,
1444 Object a4, Object a5, Object a6, Object a7,
1445 Object a8, Object a9)
1446 { return makeArray(a0, a1, a2, a3, a4, a5, a6, a7, a8, a9); }
1447
1448 private static final int ARRAYS_COUNT = 11;
1449 private static final @Stable MethodHandle[] ARRAYS = new MethodHandle[MAX_ARITY + 1];
1450
1451 // filling versions of the above:
1452 // using Integer len instead of int len and no varargs to avoid bootstrapping problems
1453 private static Object[] fillNewArray(Integer len, Object[] /*not ...*/ args) {
1454 Object[] a = new Object[len];
1455 fillWithArguments(a, 0, args);
1456 return a;
1457 }
1458 private static Object[] fillNewTypedArray(Object[] example, Integer len, Object[] /*not ...*/ args) {
1459 Object[] a = Arrays.copyOf(example, len);
1460 assert(a.getClass() != Object[].class);
1461 fillWithArguments(a, 0, args);
1462 return a;
1463 }
1464 private static void fillWithArguments(Object[] a, int pos, Object... args) {
1465 System.arraycopy(args, 0, a, pos, args.length);
1466 }
1467 // using Integer pos instead of int pos to avoid bootstrapping problems
1468 private static Object[] fillArray(Integer pos, Object[] a, Object a0)
1469 { fillWithArguments(a, pos, a0); return a; }
1470 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1)
1471 { fillWithArguments(a, pos, a0, a1); return a; }
1472 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1, Object a2)
1473 { fillWithArguments(a, pos, a0, a1, a2); return a; }
1474 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1, Object a2, Object a3)
1475 { fillWithArguments(a, pos, a0, a1, a2, a3); return a; }
1476 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1, Object a2, Object a3,
1477 Object a4)
1478 { fillWithArguments(a, pos, a0, a1, a2, a3, a4); return a; }
1479 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1, Object a2, Object a3,
1480 Object a4, Object a5)
1481 { fillWithArguments(a, pos, a0, a1, a2, a3, a4, a5); return a; }
1482 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1, Object a2, Object a3,
1483 Object a4, Object a5, Object a6)
1484 { fillWithArguments(a, pos, a0, a1, a2, a3, a4, a5, a6); return a; }
1485 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1, Object a2, Object a3,
1486 Object a4, Object a5, Object a6, Object a7)
1487 { fillWithArguments(a, pos, a0, a1, a2, a3, a4, a5, a6, a7); return a; }
1488 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1, Object a2, Object a3,
1489 Object a4, Object a5, Object a6, Object a7,
1490 Object a8)
1491 { fillWithArguments(a, pos, a0, a1, a2, a3, a4, a5, a6, a7, a8); return a; }
1492 private static Object[] fillArray(Integer pos, Object[] a, Object a0, Object a1, Object a2, Object a3,
1493 Object a4, Object a5, Object a6, Object a7,
1494 Object a8, Object a9)
1495 { fillWithArguments(a, pos, a0, a1, a2, a3, a4, a5, a6, a7, a8, a9); return a; }
1496
1497 private static final int FILL_ARRAYS_COUNT = 11; // current number of fillArray methods
1498 private static final @Stable MethodHandle[] FILL_ARRAYS = new MethodHandle[FILL_ARRAYS_COUNT];
1499
1500 private static MethodHandle getFillArray(int count) {
1501 assert (count > 0 && count < FILL_ARRAYS_COUNT);
1502 MethodHandle mh = FILL_ARRAYS[count];
1503 if (mh != null) {
1504 return mh;
1505 }
1506 mh = findCollector("fillArray", count, Object[].class, Integer.class, Object[].class);
1507 FILL_ARRAYS[count] = mh;
1508 return mh;
1509 }
1510
1511 private static Object copyAsPrimitiveArray(Wrapper w, Object... boxes) {
1512 Object a = w.makeArray(boxes.length);
1513 w.copyArrayUnboxing(boxes, 0, a, 0, boxes.length);
1514 return a;
1515 }
1516
1517 /** Return a method handle that takes the indicated number of Object
1518 * arguments and returns an Object array of them, as if for varargs.
1519 */
1520 static MethodHandle varargsArray(int nargs) {
1521 MethodHandle mh = ARRAYS[nargs];
1522 if (mh != null) {
1523 return mh;
1524 }
1525 if (nargs < ARRAYS_COUNT) {
1526 mh = findCollector("array", nargs, Object[].class);
1527 } else {
1528 mh = buildVarargsArray(getConstantHandle(MH_fillNewArray),
1529 getConstantHandle(MH_arrayIdentity), nargs);
1530 }
1531 assert(assertCorrectArity(mh, nargs));
1532 mh = makeIntrinsic(mh, Intrinsic.NEW_ARRAY);
1533 return ARRAYS[nargs] = mh;
1534 }
1535
1536 private static boolean assertCorrectArity(MethodHandle mh, int arity) {
1537 assert(mh.type().parameterCount() == arity) : "arity != "+arity+": "+mh;
1538 return true;
1539 }
1540
1541 // Array identity function (used as getConstantHandle(MH_arrayIdentity)).
1542 static <T> T[] identity(T[] x) {
1543 return x;
1544 }
1545
1546 private static MethodHandle buildVarargsArray(MethodHandle newArray, MethodHandle finisher, int nargs) {
1547 // Build up the result mh as a sequence of fills like this:
1548 // finisher(fill(fill(newArrayWA(23,x1..x10),10,x11..x20),20,x21..x23))
1549 // The various fill(_,10*I,___*[J]) are reusable.
1550 int leftLen = Math.min(nargs, LEFT_ARGS); // absorb some arguments immediately
1551 int rightLen = nargs - leftLen;
1552 MethodHandle leftCollector = newArray.bindTo(nargs);
1553 leftCollector = leftCollector.asCollector(Object[].class, leftLen);
1554 MethodHandle mh = finisher;
1555 if (rightLen > 0) {
1556 MethodHandle rightFiller = fillToRight(LEFT_ARGS + rightLen);
1557 if (mh.equals(getConstantHandle(MH_arrayIdentity)))
1558 mh = rightFiller;
1559 else
1560 mh = MethodHandles.collectArguments(mh, 0, rightFiller);
1561 }
1562 if (mh.equals(getConstantHandle(MH_arrayIdentity)))
1563 mh = leftCollector;
1564 else
1565 mh = MethodHandles.collectArguments(mh, 0, leftCollector);
1566 return mh;
1567 }
1568
1569 private static final int LEFT_ARGS = FILL_ARRAYS_COUNT - 1;
1570 private static final @Stable MethodHandle[] FILL_ARRAY_TO_RIGHT = new MethodHandle[MAX_ARITY + 1];
1571 /** fill_array_to_right(N).invoke(a, argL..arg[N-1])
1572 * fills a[L]..a[N-1] with corresponding arguments,
1573 * and then returns a. The value L is a global constant (LEFT_ARGS).
1574 */
1575 private static MethodHandle fillToRight(int nargs) {
1576 MethodHandle filler = FILL_ARRAY_TO_RIGHT[nargs];
1577 if (filler != null) return filler;
1578 filler = buildFiller(nargs);
1579 assert(assertCorrectArity(filler, nargs - LEFT_ARGS + 1));
1580 return FILL_ARRAY_TO_RIGHT[nargs] = filler;
1581 }
1582 private static MethodHandle buildFiller(int nargs) {
1583 if (nargs <= LEFT_ARGS)
1584 return getConstantHandle(MH_arrayIdentity); // no args to fill; return the array unchanged
1585 // we need room for both mh and a in mh.invoke(a, arg*[nargs])
1586 final int CHUNK = LEFT_ARGS;
1587 int rightLen = nargs % CHUNK;
1588 int midLen = nargs - rightLen;
1589 if (rightLen == 0) {
1590 midLen = nargs - (rightLen = CHUNK);
1591 if (FILL_ARRAY_TO_RIGHT[midLen] == null) {
1592 // build some precursors from left to right
1593 for (int j = LEFT_ARGS % CHUNK; j < midLen; j += CHUNK)
1594 if (j > LEFT_ARGS) fillToRight(j);
1595 }
1596 }
1597 if (midLen < LEFT_ARGS) rightLen = nargs - (midLen = LEFT_ARGS);
1598 assert(rightLen > 0);
1599 MethodHandle midFill = fillToRight(midLen); // recursive fill
1600 MethodHandle rightFill = getFillArray(rightLen).bindTo(midLen); // [midLen..nargs-1]
1601 assert(midFill.type().parameterCount() == 1 + midLen - LEFT_ARGS);
1602 assert(rightFill.type().parameterCount() == 1 + rightLen);
1603
1604 // Combine the two fills:
1605 // right(mid(a, x10..x19), x20..x23)
1606 // The final product will look like this:
1607 // right(mid(newArrayLeft(24, x0..x9), x10..x19), x20..x23)
1608 if (midLen == LEFT_ARGS)
1609 return rightFill;
1610 else
1611 return MethodHandles.collectArguments(rightFill, 0, midFill);
1612 }
1613
1614 static final int MAX_JVM_ARITY = 255; // limit imposed by the JVM
1615
1616 /** Return a method handle that takes the indicated number of
1617 * typed arguments and returns an array of them.
1618 * The type argument is the array type.
1619 */
1620 static MethodHandle varargsArray(Class<?> arrayType, int nargs) {
1621 Class<?> elemType = arrayType.getComponentType();
1622 if (elemType == null) throw new IllegalArgumentException("not an array: "+arrayType);
1623 // FIXME: Need more special casing and caching here.
1624 if (nargs >= MAX_JVM_ARITY/2 - 1) {
1625 int slots = nargs;
1626 final int MAX_ARRAY_SLOTS = MAX_JVM_ARITY - 1; // 1 for receiver MH
1627 if (slots <= MAX_ARRAY_SLOTS && elemType.isPrimitive())
1628 slots *= Wrapper.forPrimitiveType(elemType).stackSlots();
1629 if (slots > MAX_ARRAY_SLOTS)
1630 throw new IllegalArgumentException("too many arguments: "+arrayType.getSimpleName()+", length "+nargs);
1631 }
1632 if (elemType == Object.class)
1633 return varargsArray(nargs);
1634 // other cases: primitive arrays, subtypes of Object[]
1635 MethodHandle cache[] = Makers.TYPED_COLLECTORS.get(elemType);
1636 MethodHandle mh = nargs < cache.length ? cache[nargs] : null;
1637 if (mh != null) return mh;
1638 if (nargs == 0) {
1639 Object example = java.lang.reflect.Array.newInstance(arrayType.getComponentType(), 0);
1640 mh = MethodHandles.constant(arrayType, example);
1641 } else if (elemType.isPrimitive()) {
1642 MethodHandle builder = getConstantHandle(MH_fillNewArray);
1643 MethodHandle producer = buildArrayProducer(arrayType);
1644 mh = buildVarargsArray(builder, producer, nargs);
1645 } else {
1646 Class<? extends Object[]> objArrayType = arrayType.asSubclass(Object[].class);
1647 Object[] example = Arrays.copyOf(NO_ARGS_ARRAY, 0, objArrayType);
1648 MethodHandle builder = getConstantHandle(MH_fillNewTypedArray).bindTo(example);
1649 MethodHandle producer = getConstantHandle(MH_arrayIdentity); // must be weakly typed
1650 mh = buildVarargsArray(builder, producer, nargs);
1651 }
1652 mh = mh.asType(MethodType.methodType(arrayType, Collections.<Class<?>>nCopies(nargs, elemType)));
1653 mh = makeIntrinsic(mh, Intrinsic.NEW_ARRAY);
1654 assert(assertCorrectArity(mh, nargs));
1655 if (nargs < cache.length)
1656 cache[nargs] = mh;
1657 return mh;
1658 }
1659
1660 private static MethodHandle buildArrayProducer(Class<?> arrayType) {
1661 Class<?> elemType = arrayType.getComponentType();
1662 assert(elemType.isPrimitive());
1663 return getConstantHandle(MH_copyAsPrimitiveArray).bindTo(Wrapper.forPrimitiveType(elemType));
1664 }
1665
1666 /*non-public*/ static void assertSame(Object mh1, Object mh2) {
1667 if (mh1 != mh2) {
1668 String msg = String.format("mh1 != mh2: mh1 = %s (form: %s); mh2 = %s (form: %s)",
1669 mh1, ((MethodHandle)mh1).form,
1670 mh2, ((MethodHandle)mh2).form);
1671 throw newInternalError(msg);
1672 }
1673 }
1674
1675 // Local constant functions:
1676 /*non-public*/ static final NamedFunction
1677 NF_checkSpreadArgument,
1678 NF_guardWithCatch,
1679 NF_throwException,
1680 NF_tryFinally,
1681 NF_loop,
1682 NF_profileBoolean;
1683
1684 static {
1685 try {
1686 NF_checkSpreadArgument = new NamedFunction(MethodHandleImpl.class
1687 .getDeclaredMethod("checkSpreadArgument", Object.class, int.class));
1688 NF_guardWithCatch = new NamedFunction(MethodHandleImpl.class
1689 .getDeclaredMethod("guardWithCatch", MethodHandle.class, Class.class,
1690 MethodHandle.class, Object[].class));
1691 NF_tryFinally = new NamedFunction(MethodHandleImpl.class
1692 .getDeclaredMethod("tryFinally", MethodHandle.class, MethodHandle.class, Object[].class));
1693 NF_loop = new NamedFunction(MethodHandleImpl.class
1694 .getDeclaredMethod("loop", BasicType[].class, LoopClauses.class, Object[].class));
1695 NF_throwException = new NamedFunction(MethodHandleImpl.class
1696 .getDeclaredMethod("throwException", Throwable.class));
1697 NF_profileBoolean = new NamedFunction(MethodHandleImpl.class
1698 .getDeclaredMethod("profileBoolean", boolean.class, int[].class));
1699 } catch (ReflectiveOperationException ex) {
1700 throw newInternalError(ex);
1701 }
1702
1703 SharedSecrets.setJavaLangInvokeAccess(new JavaLangInvokeAccess() {
1704 @Override
1705 public Object newMemberName() {
1706 return new MemberName();
1707 }
1708
1709 @Override
1710 public String getName(Object mname) {
1711 MemberName memberName = (MemberName)mname;
1712 return memberName.getName();
1713 }
1714
1715 @Override
1716 public boolean isNative(Object mname) {
1717 MemberName memberName = (MemberName)mname;
1718 return memberName.isNative();
1719 }
1720
1721 @Override
1722 public byte[] generateDirectMethodHandleHolderClassBytes(
1723 String className, MethodType[] methodTypes, int[] types) {
1724 return GenerateJLIClassesHelper
1725 .generateDirectMethodHandleHolderClassBytes(
1726 className, methodTypes, types);
1727 }
1728
1729 @Override
1730 public byte[] generateDelegatingMethodHandleHolderClassBytes(
1731 String className, MethodType[] methodTypes) {
1732 return GenerateJLIClassesHelper
1733 .generateDelegatingMethodHandleHolderClassBytes(
1734 className, methodTypes);
1735 }
1736
1737 @Override
1738 public Map.Entry<String, byte[]> generateConcreteBMHClassBytes(
1739 final String types) {
1740 return GenerateJLIClassesHelper
1741 .generateConcreteBMHClassBytes(types);
1742 }
1743
1744 @Override
1745 public byte[] generateBasicFormsClassBytes(final String className) {
1746 return GenerateJLIClassesHelper
1747 .generateBasicFormsClassBytes(className);
1748 }
1749
1750 @Override
1751 public byte[] generateInvokersHolderClassBytes(final String className,
1752 MethodType[] methodTypes) {
1753 return GenerateJLIClassesHelper
1754 .generateInvokersHolderClassBytes(className, methodTypes);
1755 }
1756 });
1757 }
1758
1759 /** Result unboxing: ValueConversions.unbox() OR ValueConversions.identity() OR ValueConversions.ignore(). */
1760 private static MethodHandle unboxResultHandle(Class<?> returnType) {
1761 if (returnType.isPrimitive()) {
1762 if (returnType == void.class) {
1763 return ValueConversions.ignore();
1764 } else {
1765 Wrapper w = Wrapper.forPrimitiveType(returnType);
1766 return ValueConversions.unboxExact(w);
1767 }
1768 } else {
1769 return MethodHandles.identity(Object.class);
1770 }
1771 }
1772
1773 /**
1774 * Assembles a loop method handle from the given handles and type information.
1775 *
1776 * @param tloop the return type of the loop.
1777 * @param targs types of the arguments to be passed to the loop.
1778 * @param init sanitized array of initializers for loop-local variables.
1779 * @param step sanitited array of loop bodies.
1780 * @param pred sanitized array of predicates.
1781 * @param fini sanitized array of loop finalizers.
1782 *
1783 * @return a handle that, when invoked, will execute the loop.
1784 */
1785 static MethodHandle makeLoop(Class<?> tloop, List<Class<?>> targs, List<MethodHandle> init, List<MethodHandle> step,
1786 List<MethodHandle> pred, List<MethodHandle> fini) {
1787 MethodType type = MethodType.methodType(tloop, targs);
1788 BasicType[] initClauseTypes =
1789 init.stream().map(h -> h.type().returnType()).map(BasicType::basicType).toArray(BasicType[]::new);
1790 LambdaForm form = makeLoopForm(type.basicType(), initClauseTypes);
1791
1792 // Prepare auxiliary method handles used during LambdaForm interpretation.
1793 // Box arguments and wrap them into Object[]: ValueConversions.array().
1794 MethodType varargsType = type.changeReturnType(Object[].class);
1795 MethodHandle collectArgs = varargsArray(type.parameterCount()).asType(varargsType);
1796 MethodHandle unboxResult = unboxResultHandle(tloop);
1797
1798 LoopClauses clauseData =
1799 new LoopClauses(new MethodHandle[][]{toArray(init), toArray(step), toArray(pred), toArray(fini)});
1800 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLL();
1801 BoundMethodHandle mh;
1802 try {
1803 mh = (BoundMethodHandle) data.constructor().invokeBasic(type, form, (Object) clauseData,
1804 (Object) collectArgs, (Object) unboxResult);
1805 } catch (Throwable ex) {
1806 throw uncaughtException(ex);
1807 }
1808 assert(mh.type() == type);
1809 return mh;
1810 }
1811
1812 private static MethodHandle[] toArray(List<MethodHandle> l) {
1813 return l.toArray(new MethodHandle[0]);
1814 }
1815
1816 /**
1817 * Loops introduce some complexity as they can have additional local state. Hence, LambdaForms for loops are
1818 * generated from a template. The LambdaForm template shape for the loop combinator is as follows (assuming one
1819 * reference parameter passed in {@code a1}, and a reference return type, with the return value represented by
1820 * {@code t12}):
1821 * <blockquote><pre>{@code
1822 * loop=Lambda(a0:L,a1:L)=>{
1823 * t2:L=BoundMethodHandle$Species_L3.argL0(a0:L); // LoopClauses holding init, step, pred, fini handles
1824 * t3:L=BoundMethodHandle$Species_L3.argL1(a0:L); // helper handle to box the arguments into an Object[]
1825 * t4:L=BoundMethodHandle$Species_L3.argL2(a0:L); // helper handle to unbox the result
1826 * t5:L=MethodHandle.invokeBasic(t3:L,a1:L); // box the arguments into an Object[]
1827 * t6:L=MethodHandleImpl.loop(null,t2:L,t3:L); // call the loop executor
1828 * t7:L=MethodHandle.invokeBasic(t4:L,t6:L);t7:L} // unbox the result; return the result
1829 * }</pre></blockquote>
1830 * <p>
1831 * {@code argL0} is a LoopClauses instance holding, in a 2-dimensional array, the init, step, pred, and fini method
1832 * handles. {@code argL1} and {@code argL2} are auxiliary method handles: {@code argL1} boxes arguments and wraps
1833 * them into {@code Object[]} ({@code ValueConversions.array()}), and {@code argL2} unboxes the result if necessary
1834 * ({@code ValueConversions.unbox()}).
1835 * <p>
1836 * Having {@code t3} and {@code t4} passed in via a BMH and not hardcoded in the lambda form allows to share lambda
1837 * forms among loop combinators with the same basic type.
1838 * <p>
1839 * The above template is instantiated by using the {@link LambdaFormEditor} to replace the {@code null} argument to
1840 * the {@code loop} invocation with the {@code BasicType} array describing the loop clause types. This argument is
1841 * ignored in the loop invoker, but will be extracted and used in {@linkplain InvokerBytecodeGenerator#emitLoop(int)
1842 * bytecode generation}.
1843 */
1844 private static LambdaForm makeLoopForm(MethodType basicType, BasicType[] localVarTypes) {
1845 MethodType lambdaType = basicType.invokerType();
1846
1847 final int THIS_MH = 0; // the BMH_LLL
1848 final int ARG_BASE = 1; // start of incoming arguments
1849 final int ARG_LIMIT = ARG_BASE + basicType.parameterCount();
1850
1851 int nameCursor = ARG_LIMIT;
1852 final int GET_CLAUSE_DATA = nameCursor++;
1853 final int GET_COLLECT_ARGS = nameCursor++;
1854 final int GET_UNBOX_RESULT = nameCursor++;
1855 final int BOXED_ARGS = nameCursor++;
1856 final int LOOP = nameCursor++;
1857 final int UNBOX_RESULT = nameCursor++;
1858
1859 LambdaForm lform = basicType.form().cachedLambdaForm(MethodTypeForm.LF_LOOP);
1860 if (lform == null) {
1861 Name[] names = arguments(nameCursor - ARG_LIMIT, lambdaType);
1862
1863 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLL();
1864 names[THIS_MH] = names[THIS_MH].withConstraint(data);
1865 names[GET_CLAUSE_DATA] = new Name(data.getterFunction(0), names[THIS_MH]);
1866 names[GET_COLLECT_ARGS] = new Name(data.getterFunction(1), names[THIS_MH]);
1867 names[GET_UNBOX_RESULT] = new Name(data.getterFunction(2), names[THIS_MH]);
1868
1869 // t_{i}:L=MethodHandle.invokeBasic(collectArgs:L,a1:L,...);
1870 MethodType collectArgsType = basicType.changeReturnType(Object.class);
1871 MethodHandle invokeBasic = MethodHandles.basicInvoker(collectArgsType);
1872 Object[] args = new Object[invokeBasic.type().parameterCount()];
1873 args[0] = names[GET_COLLECT_ARGS];
1874 System.arraycopy(names, ARG_BASE, args, 1, ARG_LIMIT - ARG_BASE);
1875 names[BOXED_ARGS] = new Name(makeIntrinsic(invokeBasic, Intrinsic.LOOP), args);
1876
1877 // t_{i+1}:L=MethodHandleImpl.loop(localTypes:L,clauses:L,t_{i}:L);
1878 Object[] lArgs =
1879 new Object[]{null, // placeholder for BasicType[] localTypes - will be added by LambdaFormEditor
1880 names[GET_CLAUSE_DATA], names[BOXED_ARGS]};
1881 names[LOOP] = new Name(NF_loop, lArgs);
1882
1883 // t_{i+2}:I=MethodHandle.invokeBasic(unbox:L,t_{i+1}:L);
1884 MethodHandle invokeBasicUnbox = MethodHandles.basicInvoker(MethodType.methodType(basicType.rtype(), Object.class));
1885 Object[] unboxArgs = new Object[]{names[GET_UNBOX_RESULT], names[LOOP]};
1886 names[UNBOX_RESULT] = new Name(invokeBasicUnbox, unboxArgs);
1887
1888 lform = basicType.form().setCachedLambdaForm(MethodTypeForm.LF_LOOP,
1889 new LambdaForm("loop", lambdaType.parameterCount(), names));
1890 }
1891
1892 // BOXED_ARGS is the index into the names array where the loop idiom starts
1893 return lform.editor().noteLoopLocalTypesForm(BOXED_ARGS, localVarTypes);
1894 }
1895
1896 static class LoopClauses {
1897 @Stable final MethodHandle[][] clauses;
1898 LoopClauses(MethodHandle[][] clauses) {
1899 assert clauses.length == 4;
1900 this.clauses = clauses;
1901 }
1902 @Override
1903 public String toString() {
1904 StringBuffer sb = new StringBuffer("LoopClauses -- ");
1905 for (int i = 0; i < 4; ++i) {
1906 if (i > 0) {
1907 sb.appendN(' ', 7);
1908 }
1909 sb.append('<').append(i).append(">: ");
1910 MethodHandle[] hs = clauses[i];
1911 for (int j = 0; j < hs.length; ++j) {
1912 if (j > 0) {
1913 sb.appendN(' ', 10);
1914 }
1915 sb.append('*').append(j).append(": ").append(hs[j]).append('\n');
1916 }
1917 }
1918 sb.append(" --\n");
1919 return sb.toString();
1920 }
1921 }
1922
1923 /**
1924 * Intrinsified during LambdaForm compilation
1925 * (see {@link InvokerBytecodeGenerator#emitLoop(int)}).
1926 */
1927 @LambdaForm.Hidden
1928 static Object loop(BasicType[] localTypes, LoopClauses clauseData, Object... av) throws Throwable {
1929 final MethodHandle[] init = clauseData.clauses[0];
1930 final MethodHandle[] step = clauseData.clauses[1];
1931 final MethodHandle[] pred = clauseData.clauses[2];
1932 final MethodHandle[] fini = clauseData.clauses[3];
1933 int varSize = (int) Stream.of(init).filter(h -> h.type().returnType() != void.class).count();
1934 int nArgs = init[0].type().parameterCount();
1935 Object[] varsAndArgs = new Object[varSize + nArgs];
1936 for (int i = 0, v = 0; i < init.length; ++i) {
1937 MethodHandle ih = init[i];
1938 if (ih.type().returnType() == void.class) {
1939 ih.invokeWithArguments(av);
1940 } else {
1941 varsAndArgs[v++] = ih.invokeWithArguments(av);
1942 }
1943 }
1944 System.arraycopy(av, 0, varsAndArgs, varSize, nArgs);
1945 final int nSteps = step.length;
1946 for (; ; ) {
1947 for (int i = 0, v = 0; i < nSteps; ++i) {
1948 MethodHandle p = pred[i];
1949 MethodHandle s = step[i];
1950 MethodHandle f = fini[i];
1951 if (s.type().returnType() == void.class) {
1952 s.invokeWithArguments(varsAndArgs);
1953 } else {
1954 varsAndArgs[v++] = s.invokeWithArguments(varsAndArgs);
1955 }
1956 if (!(boolean) p.invokeWithArguments(varsAndArgs)) {
1957 return f.invokeWithArguments(varsAndArgs);
1958 }
1959 }
1960 }
1961 }
1962
1963 /**
1964 * This method is bound as the predicate in {@linkplain MethodHandles#countedLoop(MethodHandle, MethodHandle,
1965 * MethodHandle) counting loops}.
1966 *
1967 * @param limit the upper bound of the parameter, statically bound at loop creation time.
1968 * @param counter the counter parameter, passed in during loop execution.
1969 *
1970 * @return whether the counter has reached the limit.
1971 */
1972 static boolean countedLoopPredicate(int limit, int counter) {
1973 return counter < limit;
1974 }
1975
1976 /**
1977 * This method is bound as the step function in {@linkplain MethodHandles#countedLoop(MethodHandle, MethodHandle,
1978 * MethodHandle) counting loops} to increment the counter.
1979 *
1980 * @param limit the upper bound of the loop counter (ignored).
1981 * @param counter the loop counter.
1982 *
1983 * @return the loop counter incremented by 1.
1984 */
1985 static int countedLoopStep(int limit, int counter) {
1986 return counter + 1;
1987 }
1988
1989 /**
1990 * This is bound to initialize the loop-local iterator in {@linkplain MethodHandles#iteratedLoop iterating loops}.
1991 *
1992 * @param it the {@link Iterable} over which the loop iterates.
1993 *
1994 * @return an {@link Iterator} over the argument's elements.
1995 */
1996 static Iterator<?> initIterator(Iterable<?> it) {
1997 return it.iterator();
1998 }
1999
2000 /**
2001 * This method is bound as the predicate in {@linkplain MethodHandles#iteratedLoop iterating loops}.
2002 *
2003 * @param it the iterator to be checked.
2004 *
2005 * @return {@code true} iff there are more elements to iterate over.
2006 */
2007 static boolean iteratePredicate(Iterator<?> it) {
2008 return it.hasNext();
2009 }
2010
2011 /**
2012 * This method is bound as the step for retrieving the current value from the iterator in {@linkplain
2013 * MethodHandles#iteratedLoop iterating loops}.
2014 *
2015 * @param it the iterator.
2016 *
2017 * @return the next element from the iterator.
2018 */
2019 static Object iterateNext(Iterator<?> it) {
2020 return it.next();
2021 }
2022
2023 /**
2024 * Makes a {@code try-finally} handle that conforms to the type constraints.
2025 *
2026 * @param target the target to execute in a {@code try-finally} block.
2027 * @param cleanup the cleanup to execute in the {@code finally} block.
2028 * @param rtype the result type of the entire construct.
2029 * @param argTypes the types of the arguments.
2030 *
2031 * @return a handle on the constructed {@code try-finally} block.
2032 */
2033 static MethodHandle makeTryFinally(MethodHandle target, MethodHandle cleanup, Class<?> rtype, List<Class<?>> argTypes) {
2034 MethodType type = MethodType.methodType(rtype, argTypes);
2035 LambdaForm form = makeTryFinallyForm(type.basicType());
2036
2037 // Prepare auxiliary method handles used during LambdaForm interpretation.
2038 // Box arguments and wrap them into Object[]: ValueConversions.array().
2039 MethodType varargsType = type.changeReturnType(Object[].class);
2040 MethodHandle collectArgs = varargsArray(type.parameterCount()).asType(varargsType);
2041 MethodHandle unboxResult = unboxResultHandle(rtype);
2042
2043 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLLL();
2044 BoundMethodHandle mh;
2045 try {
2046 mh = (BoundMethodHandle) data.constructor().invokeBasic(type, form, (Object) target, (Object) cleanup,
2047 (Object) collectArgs, (Object) unboxResult);
2048 } catch (Throwable ex) {
2049 throw uncaughtException(ex);
2050 }
2051 assert(mh.type() == type);
2052 return mh;
2053 }
2054
2055 /**
2056 * The LambdaForm shape for the tryFinally combinator is as follows (assuming one reference parameter passed in
2057 * {@code a1}, and a reference return type, with the return value represented by {@code t8}):
2058 * <blockquote><pre>{@code
2059 * tryFinally=Lambda(a0:L,a1:L)=>{
2060 * t2:L=BoundMethodHandle$Species_LLLL.argL0(a0:L); // target method handle
2061 * t3:L=BoundMethodHandle$Species_LLLL.argL1(a0:L); // cleanup method handle
2062 * t4:L=BoundMethodHandle$Species_LLLL.argL2(a0:L); // helper handle to box the arguments into an Object[]
2063 * t5:L=BoundMethodHandle$Species_LLLL.argL3(a0:L); // helper handle to unbox the result
2064 * t6:L=MethodHandle.invokeBasic(t4:L,a1:L); // box the arguments into an Object[]
2065 * t7:L=MethodHandleImpl.tryFinally(t2:L,t3:L,t6:L); // call the tryFinally executor
2066 * t8:L=MethodHandle.invokeBasic(t5:L,t7:L);t8:L} // unbox the result; return the result
2067 * }</pre></blockquote>
2068 * <p>
2069 * {@code argL0} and {@code argL1} are the target and cleanup method handles.
2070 * {@code argL2} and {@code argL3} are auxiliary method handles: {@code argL2} boxes arguments and wraps them into
2071 * {@code Object[]} ({@code ValueConversions.array()}), and {@code argL3} unboxes the result if necessary
2072 * ({@code ValueConversions.unbox()}).
2073 * <p>
2074 * Having {@code t4} and {@code t5} passed in via a BMH and not hardcoded in the lambda form allows to share lambda
2075 * forms among tryFinally combinators with the same basic type.
2076 */
2077 private static LambdaForm makeTryFinallyForm(MethodType basicType) {
2078 MethodType lambdaType = basicType.invokerType();
2079
2080 LambdaForm lform = basicType.form().cachedLambdaForm(MethodTypeForm.LF_TF);
2081 if (lform != null) {
2082 return lform;
2083 }
2084 final int THIS_MH = 0; // the BMH_LLLL
2085 final int ARG_BASE = 1; // start of incoming arguments
2086 final int ARG_LIMIT = ARG_BASE + basicType.parameterCount();
2087
2088 int nameCursor = ARG_LIMIT;
2089 final int GET_TARGET = nameCursor++;
2090 final int GET_CLEANUP = nameCursor++;
2091 final int GET_COLLECT_ARGS = nameCursor++;
2092 final int GET_UNBOX_RESULT = nameCursor++;
2093 final int BOXED_ARGS = nameCursor++;
2094 final int TRY_FINALLY = nameCursor++;
2095 final int UNBOX_RESULT = nameCursor++;
2096
2097 Name[] names = arguments(nameCursor - ARG_LIMIT, lambdaType);
2098
2099 BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLLL();
2100 names[THIS_MH] = names[THIS_MH].withConstraint(data);
2101 names[GET_TARGET] = new Name(data.getterFunction(0), names[THIS_MH]);
2102 names[GET_CLEANUP] = new Name(data.getterFunction(1), names[THIS_MH]);
2103 names[GET_COLLECT_ARGS] = new Name(data.getterFunction(2), names[THIS_MH]);
2104 names[GET_UNBOX_RESULT] = new Name(data.getterFunction(3), names[THIS_MH]);
2105
2106 // t_{i}:L=MethodHandle.invokeBasic(collectArgs:L,a1:L,...);
2107 MethodType collectArgsType = basicType.changeReturnType(Object.class);
2108 MethodHandle invokeBasic = MethodHandles.basicInvoker(collectArgsType);
2109 Object[] args = new Object[invokeBasic.type().parameterCount()];
2110 args[0] = names[GET_COLLECT_ARGS];
2111 System.arraycopy(names, ARG_BASE, args, 1, ARG_LIMIT-ARG_BASE);
2112 names[BOXED_ARGS] = new Name(makeIntrinsic(invokeBasic, Intrinsic.TRY_FINALLY), args);
2113
2114 // t_{i+1}:L=MethodHandleImpl.tryFinally(target:L,exType:L,catcher:L,t_{i}:L);
2115 Object[] tfArgs = new Object[] {names[GET_TARGET], names[GET_CLEANUP], names[BOXED_ARGS]};
2116 names[TRY_FINALLY] = new Name(NF_tryFinally, tfArgs);
2117
2118 // t_{i+2}:I=MethodHandle.invokeBasic(unbox:L,t_{i+1}:L);
2119 MethodHandle invokeBasicUnbox = MethodHandles.basicInvoker(MethodType.methodType(basicType.rtype(), Object.class));
2120 Object[] unboxArgs = new Object[] {names[GET_UNBOX_RESULT], names[TRY_FINALLY]};
2121 names[UNBOX_RESULT] = new Name(invokeBasicUnbox, unboxArgs);
2122
2123 lform = new LambdaForm("tryFinally", lambdaType.parameterCount(), names);
2124
2125 return basicType.form().setCachedLambdaForm(MethodTypeForm.LF_TF, lform);
2126 }
2127
2128 /**
2129 * Intrinsified during LambdaForm compilation
2130 * (see {@link InvokerBytecodeGenerator#emitTryFinally emitTryFinally}).
2131 */
2132 @LambdaForm.Hidden
2133 static Object tryFinally(MethodHandle target, MethodHandle cleanup, Object... av) throws Throwable {
2134 Throwable t = null;
2135 Object r = null;
2136 try {
2137 r = target.invokeWithArguments(av);
2138 } catch (Throwable thrown) {
2139 t = thrown;
2140 throw t;
2141 } finally {
2142 Object[] args = target.type().returnType() == void.class ? prepend(av, t) : prepend(av, t, r);
2143 r = cleanup.invokeWithArguments(args);
2144 }
2145 return r;
2146 }
2147
2148 // Indexes into constant method handles:
2149 static final int
2150 MH_cast = 0,
2151 MH_selectAlternative = 1,
2152 MH_copyAsPrimitiveArray = 2,
2153 MH_fillNewTypedArray = 3,
2154 MH_fillNewArray = 4,
2155 MH_arrayIdentity = 5,
2156 MH_countedLoopPred = 6,
2157 MH_countedLoopStep = 7,
2158 MH_initIterator = 8,
2159 MH_iteratePred = 9,
2160 MH_iterateNext = 10,
2161 MH_Array_newInstance = 11,
2162 MH_LIMIT = 12;
2163
2164 static MethodHandle getConstantHandle(int idx) {
2165 MethodHandle handle = HANDLES[idx];
2166 if (handle != null) {
2167 return handle;
2168 }
2169 return setCachedHandle(idx, makeConstantHandle(idx));
2170 }
2171
2172 private static synchronized MethodHandle setCachedHandle(int idx, final MethodHandle method) {
2173 // Simulate a CAS, to avoid racy duplication of results.
2174 MethodHandle prev = HANDLES[idx];
2175 if (prev != null) {
2176 return prev;
2177 }
2178 HANDLES[idx] = method;
2179 return method;
2180 }
2181
2182 // Local constant method handles:
2183 private static final @Stable MethodHandle[] HANDLES = new MethodHandle[MH_LIMIT];
2184
2185 private static MethodHandle makeConstantHandle(int idx) {
2186 try {
2187 switch (idx) {
2188 case MH_cast:
2189 return IMPL_LOOKUP.findVirtual(Class.class, "cast",
2190 MethodType.methodType(Object.class, Object.class));
2191 case MH_copyAsPrimitiveArray:
2192 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "copyAsPrimitiveArray",
2193 MethodType.methodType(Object.class, Wrapper.class, Object[].class));
2194 case MH_arrayIdentity:
2195 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "identity",
2196 MethodType.methodType(Object[].class, Object[].class));
2197 case MH_fillNewArray:
2198 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "fillNewArray",
2199 MethodType.methodType(Object[].class, Integer.class, Object[].class));
2200 case MH_fillNewTypedArray:
2201 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "fillNewTypedArray",
2202 MethodType.methodType(Object[].class, Object[].class, Integer.class, Object[].class));
2203 case MH_selectAlternative:
2204 return makeIntrinsic(IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "selectAlternative",
2205 MethodType.methodType(MethodHandle.class, boolean.class, MethodHandle.class, MethodHandle.class)),
2206 Intrinsic.SELECT_ALTERNATIVE);
2207 case MH_countedLoopPred:
2208 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "countedLoopPredicate",
2209 MethodType.methodType(boolean.class, int.class, int.class));
2210 case MH_countedLoopStep:
2211 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "countedLoopStep",
2212 MethodType.methodType(int.class, int.class, int.class));
2213 case MH_initIterator:
2214 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "initIterator",
2215 MethodType.methodType(Iterator.class, Iterable.class));
2216 case MH_iteratePred:
2217 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "iteratePredicate",
2218 MethodType.methodType(boolean.class, Iterator.class));
2219 case MH_iterateNext:
2220 return IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "iterateNext",
2221 MethodType.methodType(Object.class, Iterator.class));
2222 case MH_Array_newInstance:
2223 return IMPL_LOOKUP.findStatic(Array.class, "newInstance",
2224 MethodType.methodType(Object.class, Class.class, int.class));
2225 }
2226 } catch (ReflectiveOperationException ex) {
2227 throw newInternalError(ex);
2228 }
2229 throw newInternalError("Unknown function index: " + idx);
2230 }
2231 }