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.loader.BootLoader;
29 import jdk.internal.org.objectweb.asm.ClassWriter;
30 import jdk.internal.org.objectweb.asm.FieldVisitor;
31 import jdk.internal.org.objectweb.asm.MethodVisitor;
32 import jdk.internal.vm.annotation.Stable;
33 import sun.invoke.util.ValueConversions;
34 import sun.invoke.util.Wrapper;
35
36 import java.lang.invoke.LambdaForm.NamedFunction;
37 import java.lang.invoke.MethodHandles.Lookup;
38 import java.lang.reflect.Field;
39 import java.util.concurrent.ConcurrentHashMap;
40 import java.util.concurrent.ConcurrentMap;
41 import java.util.function.Function;
42
43 import static java.lang.invoke.LambdaForm.BasicType;
44 import static java.lang.invoke.LambdaForm.BasicType.*;
45 import static java.lang.invoke.MethodHandleStatics.*;
46 import static jdk.internal.org.objectweb.asm.Opcodes.*;
47
48 /**
49 * The flavor of method handle which emulates an invoke instruction
50 * on a predetermined argument. The JVM dispatches to the correct method
51 * when the handle is created, not when it is invoked.
52 *
53 * All bound arguments are encapsulated in dedicated species.
54 */
55 /*non-public*/ abstract class BoundMethodHandle extends MethodHandle {
56
57 /*non-public*/ BoundMethodHandle(MethodType type, LambdaForm form) {
58 super(type, form);
59 assert(speciesData() == speciesData(form));
60 }
61
62 //
63 // BMH API and internals
64 //
65
66 static BoundMethodHandle bindSingle(MethodType type, LambdaForm form, BasicType xtype, Object x) {
67 // for some type signatures, there exist pre-defined concrete BMH classes
68 try {
69 switch (xtype) {
70 case L_TYPE:
71 return bindSingle(type, form, x); // Use known fast path.
72 case I_TYPE:
73 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(I_TYPE).constructor().invokeBasic(type, form, ValueConversions.widenSubword(x));
74 case J_TYPE:
75 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(J_TYPE).constructor().invokeBasic(type, form, (long) x);
76 case F_TYPE:
77 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(F_TYPE).constructor().invokeBasic(type, form, (float) x);
78 case D_TYPE:
79 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(D_TYPE).constructor().invokeBasic(type, form, (double) x);
80 default : throw newInternalError("unexpected xtype: " + xtype);
81 }
82 } catch (Throwable t) {
83 throw uncaughtException(t);
84 }
85 }
86
87 /*non-public*/
88 LambdaFormEditor editor() {
89 return form.editor();
90 }
91
92 static BoundMethodHandle bindSingle(MethodType type, LambdaForm form, Object x) {
93 return Species_L.make(type, form, x);
94 }
95
96 @Override // there is a default binder in the super class, for 'L' types only
97 /*non-public*/
98 BoundMethodHandle bindArgumentL(int pos, Object value) {
99 return editor().bindArgumentL(this, pos, value);
100 }
101 /*non-public*/
102 BoundMethodHandle bindArgumentI(int pos, int value) {
103 return editor().bindArgumentI(this, pos, value);
104 }
105 /*non-public*/
106 BoundMethodHandle bindArgumentJ(int pos, long value) {
107 return editor().bindArgumentJ(this, pos, value);
108 }
109 /*non-public*/
110 BoundMethodHandle bindArgumentF(int pos, float value) {
111 return editor().bindArgumentF(this, pos, value);
112 }
113 /*non-public*/
114 BoundMethodHandle bindArgumentD(int pos, double value) {
115 return editor().bindArgumentD(this, pos, value);
116 }
117
118 @Override
119 BoundMethodHandle rebind() {
120 if (!tooComplex()) {
121 return this;
122 }
123 return makeReinvoker(this);
124 }
125
126 private boolean tooComplex() {
127 return (fieldCount() > FIELD_COUNT_THRESHOLD ||
128 form.expressionCount() > FORM_EXPRESSION_THRESHOLD);
129 }
130 private static final int FIELD_COUNT_THRESHOLD = 12; // largest convenient BMH field count
131 private static final int FORM_EXPRESSION_THRESHOLD = 24; // largest convenient BMH expression count
132
133 /**
134 * A reinvoker MH has this form:
135 * {@code lambda (bmh, arg*) { thismh = bmh[0]; invokeBasic(thismh, arg*) }}
136 */
137 static BoundMethodHandle makeReinvoker(MethodHandle target) {
138 LambdaForm form = DelegatingMethodHandle.makeReinvokerForm(
139 target, MethodTypeForm.LF_REBIND,
140 Species_L.SPECIES_DATA, Species_L.SPECIES_DATA.getterFunction(0));
141 return Species_L.make(target.type(), form, target);
142 }
143
144 /**
145 * Return the {@link SpeciesData} instance representing this BMH species. All subclasses must provide a
146 * static field containing this value, and they must accordingly implement this method.
147 */
148 /*non-public*/ abstract SpeciesData speciesData();
149
150 /*non-public*/ static SpeciesData speciesData(LambdaForm form) {
151 Object c = form.names[0].constraint;
152 if (c instanceof SpeciesData)
153 return (SpeciesData) c;
154 // if there is no BMH constraint, then use the null constraint
155 return SpeciesData.EMPTY;
156 }
157
158 /**
159 * Return the number of fields in this BMH. Equivalent to speciesData().fieldCount().
160 */
161 /*non-public*/ abstract int fieldCount();
162
163 @Override
164 Object internalProperties() {
165 return "\n& BMH="+internalValues();
166 }
167
168 @Override
169 final String internalValues() {
170 int count = speciesData().fieldCount();
171 if (count == 1) {
172 return "[" + arg(0) + "]";
173 }
174 StringBuilder sb = new StringBuilder("[");
175 for (int i = 0; i < count; ++i) {
176 sb.append("\n ").append(i).append(": ( ").append(arg(i)).append(" )");
177 }
178 return sb.append("\n]").toString();
179 }
180
181 /*non-public*/ final Object arg(int i) {
182 try {
183 switch (speciesData().fieldType(i)) {
184 case L_TYPE: return speciesData().getters[i].invokeBasic(this);
185 case I_TYPE: return (int) speciesData().getters[i].invokeBasic(this);
186 case J_TYPE: return (long) speciesData().getters[i].invokeBasic(this);
187 case F_TYPE: return (float) speciesData().getters[i].invokeBasic(this);
188 case D_TYPE: return (double) speciesData().getters[i].invokeBasic(this);
189 }
190 } catch (Throwable ex) {
191 throw uncaughtException(ex);
192 }
193 throw new InternalError("unexpected type: " + speciesData().typeChars+"."+i);
194 }
195
196 //
197 // cloning API
198 //
199
200 /*non-public*/ abstract BoundMethodHandle copyWith(MethodType mt, LambdaForm lf);
201 /*non-public*/ abstract BoundMethodHandle copyWithExtendL(MethodType mt, LambdaForm lf, Object narg);
202 /*non-public*/ abstract BoundMethodHandle copyWithExtendI(MethodType mt, LambdaForm lf, int narg);
203 /*non-public*/ abstract BoundMethodHandle copyWithExtendJ(MethodType mt, LambdaForm lf, long narg);
204 /*non-public*/ abstract BoundMethodHandle copyWithExtendF(MethodType mt, LambdaForm lf, float narg);
205 /*non-public*/ abstract BoundMethodHandle copyWithExtendD(MethodType mt, LambdaForm lf, double narg);
206
207 //
208 // concrete BMH classes required to close bootstrap loops
209 //
210
211 private // make it private to force users to access the enclosing class first
212 static final class Species_L extends BoundMethodHandle {
213 final Object argL0;
214 private Species_L(MethodType mt, LambdaForm lf, Object argL0) {
215 super(mt, lf);
216 this.argL0 = argL0;
217 }
218 @Override
219 /*non-public*/ SpeciesData speciesData() {
220 return SPECIES_DATA;
221 }
222 @Override
223 /*non-public*/ int fieldCount() {
224 return 1;
225 }
226 /*non-public*/ static final SpeciesData SPECIES_DATA = new SpeciesData("L", Species_L.class);
227 /*non-public*/ static BoundMethodHandle make(MethodType mt, LambdaForm lf, Object argL0) {
228 return new Species_L(mt, lf, argL0);
229 }
230 @Override
231 /*non-public*/ final BoundMethodHandle copyWith(MethodType mt, LambdaForm lf) {
232 return new Species_L(mt, lf, argL0);
233 }
234 @Override
235 /*non-public*/ final BoundMethodHandle copyWithExtendL(MethodType mt, LambdaForm lf, Object narg) {
236 try {
237 return (BoundMethodHandle) SPECIES_DATA.extendWith(L_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);
238 } catch (Throwable ex) {
239 throw uncaughtException(ex);
240 }
241 }
242 @Override
243 /*non-public*/ final BoundMethodHandle copyWithExtendI(MethodType mt, LambdaForm lf, int narg) {
244 try {
245 return (BoundMethodHandle) SPECIES_DATA.extendWith(I_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);
246 } catch (Throwable ex) {
247 throw uncaughtException(ex);
248 }
249 }
250 @Override
251 /*non-public*/ final BoundMethodHandle copyWithExtendJ(MethodType mt, LambdaForm lf, long narg) {
252 try {
253 return (BoundMethodHandle) SPECIES_DATA.extendWith(J_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);
254 } catch (Throwable ex) {
255 throw uncaughtException(ex);
256 }
257 }
258 @Override
259 /*non-public*/ final BoundMethodHandle copyWithExtendF(MethodType mt, LambdaForm lf, float narg) {
260 try {
261 return (BoundMethodHandle) SPECIES_DATA.extendWith(F_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);
262 } catch (Throwable ex) {
263 throw uncaughtException(ex);
264 }
265 }
266 @Override
267 /*non-public*/ final BoundMethodHandle copyWithExtendD(MethodType mt, LambdaForm lf, double narg) {
268 try {
269 return (BoundMethodHandle) SPECIES_DATA.extendWith(D_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);
270 } catch (Throwable ex) {
271 throw uncaughtException(ex);
272 }
273 }
274 }
275
276 //
277 // BMH species meta-data
278 //
279
280 /**
281 * Meta-data wrapper for concrete BMH types.
282 * Each BMH type corresponds to a given sequence of basic field types (LIJFD).
283 * The fields are immutable; their values are fully specified at object construction.
284 * Each BMH type supplies an array of getter functions which may be used in lambda forms.
285 * A BMH is constructed by cloning a shorter BMH and adding one or more new field values.
286 * The shortest possible BMH has zero fields; its class is SimpleMethodHandle.
287 * BMH species are not interrelated by subtyping, even though it would appear that
288 * a shorter BMH could serve as a supertype of a longer one which extends it.
289 */
290 static class SpeciesData {
291 private final String typeChars;
292 private final BasicType[] typeCodes;
293 private final Class<? extends BoundMethodHandle> clazz;
294 // Bootstrapping requires circular relations MH -> BMH -> SpeciesData -> MH
295 // Therefore, we need a non-final link in the chain. Use array elements.
296 @Stable private final MethodHandle[] constructor;
297 @Stable private final MethodHandle[] getters;
298 @Stable private final NamedFunction[] nominalGetters;
299 @Stable private final SpeciesData[] extensions;
300
301 /*non-public*/ int fieldCount() {
302 return typeCodes.length;
303 }
304 /*non-public*/ BasicType fieldType(int i) {
305 return typeCodes[i];
306 }
307 /*non-public*/ char fieldTypeChar(int i) {
308 return typeChars.charAt(i);
309 }
310 String fieldSignature() {
311 return typeChars;
312 }
313 public Class<? extends BoundMethodHandle> fieldHolder() {
314 return clazz;
315 }
316 public String toString() {
317 return "SpeciesData<"+fieldSignature()+">";
318 }
319
320 /**
321 * Return a {@link LambdaForm.Name} containing a {@link LambdaForm.NamedFunction} that
322 * represents a MH bound to a generic invoker, which in turn forwards to the corresponding
323 * getter.
324 */
325 NamedFunction getterFunction(int i) {
326 NamedFunction nf = nominalGetters[i];
327 assert(nf.memberDeclaringClassOrNull() == fieldHolder());
328 assert(nf.returnType() == fieldType(i));
329 return nf;
330 }
331
332 NamedFunction[] getterFunctions() {
333 return nominalGetters;
334 }
335
336 MethodHandle[] getterHandles() { return getters; }
337
338 MethodHandle constructor() {
339 return constructor[0];
340 }
341
342 static final SpeciesData EMPTY = new SpeciesData("", BoundMethodHandle.class);
343
344 SpeciesData(String types, Class<? extends BoundMethodHandle> clazz) {
345 this.typeChars = types;
346 this.typeCodes = basicTypes(types);
347 this.clazz = clazz;
348 if (!INIT_DONE) {
349 this.constructor = new MethodHandle[1]; // only one ctor
350 this.getters = new MethodHandle[types.length()];
351 this.nominalGetters = new NamedFunction[types.length()];
352 } else {
353 this.constructor = Factory.makeCtors(clazz, types, null);
354 this.getters = Factory.makeGetters(clazz, types, null);
355 this.nominalGetters = Factory.makeNominalGetters(types, null, this.getters);
356 }
357 this.extensions = new SpeciesData[ARG_TYPE_LIMIT];
358 }
359
360 private void initForBootstrap() {
361 assert(!INIT_DONE);
362 if (constructor() == null) {
363 String types = typeChars;
364 CACHE.put(types, this);
365 Factory.makeCtors(clazz, types, this.constructor);
366 Factory.makeGetters(clazz, types, this.getters);
367 Factory.makeNominalGetters(types, this.nominalGetters, this.getters);
368 }
369 }
370
371 private static final ConcurrentMap<String, SpeciesData> CACHE = new ConcurrentHashMap<>();
372 private static final boolean INIT_DONE; // set after <clinit> finishes...
373
374 SpeciesData extendWith(byte type) {
375 return extendWith(BasicType.basicType(type));
376 }
377
378 SpeciesData extendWith(BasicType type) {
379 int ord = type.ordinal();
380 SpeciesData d = extensions[ord];
381 if (d != null) return d;
382 extensions[ord] = d = get(typeChars+type.basicTypeChar());
383 return d;
384 }
385
386 private static SpeciesData get(String types) {
387 return CACHE.computeIfAbsent(types, new Function<String, SpeciesData>() {
388 @Override
389 public SpeciesData apply(String types) {
390 Class<? extends BoundMethodHandle> bmhcl = Factory.getConcreteBMHClass(types);
391 // SpeciesData instantiation may throw VirtualMachineError because of
392 // code cache overflow...
393 SpeciesData speciesData = new SpeciesData(types, bmhcl);
394 // CHM.computeIfAbsent ensures only one SpeciesData will be set
395 // successfully on the concrete BMH class if ever
396 Factory.setSpeciesDataToConcreteBMHClass(bmhcl, speciesData);
397 // the concrete BMH class is published via SpeciesData instance
398 // returned here only after it's SPECIES_DATA field is set
399 return speciesData;
400 }
401 });
402 }
403
404 /**
405 * This is to be called when assertions are enabled. It checks whether SpeciesData for all of the statically
406 * defined species subclasses of BoundMethodHandle has been added to the SpeciesData cache. See below in the
407 * static initializer for
408 */
409 static boolean speciesDataCachePopulated() {
410 Class<BoundMethodHandle> rootCls = BoundMethodHandle.class;
411 for (Class<?> c : rootCls.getDeclaredClasses()) {
412 if (rootCls.isAssignableFrom(c)) {
413 final Class<? extends BoundMethodHandle> cbmh = c.asSubclass(BoundMethodHandle.class);
414 SpeciesData d = Factory.getSpeciesDataFromConcreteBMHClass(cbmh);
415 assert(d != null) : cbmh.getName();
416 assert(d.clazz == cbmh);
417 assert(CACHE.get(d.typeChars) == d);
418 }
419 }
420 return true;
421 }
422
423 static {
424 // Pre-fill the BMH species-data cache with EMPTY and all BMH's inner subclasses.
425 EMPTY.initForBootstrap();
426 Species_L.SPECIES_DATA.initForBootstrap();
427 // check that all static SpeciesData instances have been initialized
428 assert speciesDataCachePopulated();
429 // Note: Do not simplify this, because INIT_DONE must not be
430 // a compile-time constant during bootstrapping.
431 INIT_DONE = Boolean.TRUE;
432 }
433 }
434
435 static SpeciesData getSpeciesData(String types) {
436 return SpeciesData.get(types);
437 }
438
439 /**
440 * Generation of concrete BMH classes.
441 *
442 * A concrete BMH species is fit for binding a number of values adhering to a
443 * given type pattern. Reference types are erased.
444 *
445 * BMH species are cached by type pattern.
446 *
447 * A BMH species has a number of fields with the concrete (possibly erased) types of
448 * bound values. Setters are provided as an API in BMH. Getters are exposed as MHs,
449 * which can be included as names in lambda forms.
450 */
451 static class Factory {
452
453 private static final String JLO_SIG = "Ljava/lang/Object;";
454 private static final String MH = "java/lang/invoke/MethodHandle";
455 private static final String MH_SIG = "L"+MH+";";
456 private static final String BMH = "java/lang/invoke/BoundMethodHandle";
457 private static final String BMH_NAME = "java.lang.invoke.BoundMethodHandle";
458 private static final String BMH_SIG = "L"+BMH+";";
459 private static final String SPECIES_DATA = "java/lang/invoke/BoundMethodHandle$SpeciesData";
460 private static final String SPECIES_DATA_SIG = "L"+SPECIES_DATA+";";
461 private static final String STABLE_SIG = "Ljdk/internal/vm/annotation/Stable;";
462
463 private static final String SPECIES_PREFIX_NAME = "Species_";
464 private static final String SPECIES_PREFIX_PATH = BMH + "$" + SPECIES_PREFIX_NAME;
465 private static final String SPECIES_CLASS_PREFIX = BMH_NAME + "$" + SPECIES_PREFIX_NAME;
466
467 private static final String BMHSPECIES_DATA_EWI_SIG = "(B)" + SPECIES_DATA_SIG;
468 private static final String MYSPECIES_DATA_SIG = "()" + SPECIES_DATA_SIG;
469 private static final String INT_SIG = "()I";
470
471 private static final String SIG_INCIPIT = "(Ljava/lang/invoke/MethodType;Ljava/lang/invoke/LambdaForm;";
472
473 private static final String[] E_THROWABLE = new String[] { "java/lang/Throwable" };
474
475 private static final ConcurrentMap<String, Class<? extends BoundMethodHandle>> CLASS_CACHE = new ConcurrentHashMap<>();
476
477 /**
478 * Get a concrete subclass of BMH for a given combination of bound types.
479 *
480 * @param types the type signature, wherein reference types are erased to 'L'
481 * @return the concrete BMH class
482 */
483 static Class<? extends BoundMethodHandle> getConcreteBMHClass(String types) {
484 // CHM.computeIfAbsent ensures generateConcreteBMHClass is called
485 // only once per key.
486 return CLASS_CACHE.computeIfAbsent(
487 types, new Function<String, Class<? extends BoundMethodHandle>>() {
488 @Override
489 public Class<? extends BoundMethodHandle> apply(String types) {
490 String shortTypes = LambdaForm.shortenSignature(types);
491 String className = SPECIES_CLASS_PREFIX + shortTypes;
492 Class<?> c = BootLoader.loadClassOrNull(className);
493 if (TRACE_RESOLVE) {
494 System.out.println("[BMH_RESOLVE] " + shortTypes +
495 (c != null ? " (success)" : " (fail)") );
496 }
497 if (c != null) {
498 return c.asSubclass(BoundMethodHandle.class);
499 } else {
500 // Not pregenerated, generate the class
501 return generateConcreteBMHClass(shortTypes, types);
502 }
503 }
504 });
505 }
506
507 /**
508 * Generate a concrete subclass of BMH for a given combination of bound types.
509 *
510 * A concrete BMH species adheres to the following schema:
511 *
512 * <pre>
513 * class Species_[[types]] extends BoundMethodHandle {
514 * [[fields]]
515 * final SpeciesData speciesData() { return SpeciesData.get("[[types]]"); }
516 * }
517 * </pre>
518 *
519 * The {@code [[types]]} signature is precisely the string that is passed to this
520 * method.
521 *
522 * The {@code [[fields]]} section consists of one field definition per character in
523 * the type signature, adhering to the naming schema described in the definition of
524 * {@link #makeFieldName}.
525 *
526 * For example, a concrete BMH species for two reference and one integral bound values
527 * would have the following shape:
528 *
529 * <pre>
530 * class BoundMethodHandle { ... private static
531 * final class Species_LLI extends BoundMethodHandle {
532 * final Object argL0;
533 * final Object argL1;
534 * final int argI2;
535 * private Species_LLI(MethodType mt, LambdaForm lf, Object argL0, Object argL1, int argI2) {
536 * super(mt, lf);
537 * this.argL0 = argL0;
538 * this.argL1 = argL1;
539 * this.argI2 = argI2;
540 * }
541 * final SpeciesData speciesData() { return SPECIES_DATA; }
542 * final int fieldCount() { return 3; }
543 * @Stable static SpeciesData SPECIES_DATA; // injected afterwards
544 * static BoundMethodHandle make(MethodType mt, LambdaForm lf, Object argL0, Object argL1, int argI2) {
545 * return new Species_LLI(mt, lf, argL0, argL1, argI2);
546 * }
547 * final BoundMethodHandle copyWith(MethodType mt, LambdaForm lf) {
548 * return new Species_LLI(mt, lf, argL0, argL1, argI2);
549 * }
550 * final BoundMethodHandle copyWithExtendL(MethodType mt, LambdaForm lf, Object narg) {
551 * return SPECIES_DATA.extendWith(L_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);
552 * }
553 * final BoundMethodHandle copyWithExtendI(MethodType mt, LambdaForm lf, int narg) {
554 * return SPECIES_DATA.extendWith(I_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);
555 * }
556 * final BoundMethodHandle copyWithExtendJ(MethodType mt, LambdaForm lf, long narg) {
557 * return SPECIES_DATA.extendWith(J_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);
558 * }
559 * final BoundMethodHandle copyWithExtendF(MethodType mt, LambdaForm lf, float narg) {
560 * return SPECIES_DATA.extendWith(F_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);
561 * }
562 * public final BoundMethodHandle copyWithExtendD(MethodType mt, LambdaForm lf, double narg) {
563 * return SPECIES_DATA.extendWith(D_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);
564 * }
565 * }
566 * </pre>
567 *
568 * @param types the type signature, wherein reference types are erased to 'L'
569 * @return the generated concrete BMH class
570 */
571 static Class<? extends BoundMethodHandle> generateConcreteBMHClass(String shortTypes,
572 String types) {
573 final String className = speciesInternalClassName(shortTypes);
574 byte[] classFile = generateConcreteBMHClassBytes(shortTypes, types, className);
575
576 // load class
577 InvokerBytecodeGenerator.maybeDump(className, classFile);
578 Class<? extends BoundMethodHandle> bmhClass =
579 UNSAFE.defineClass(className, classFile, 0, classFile.length,
580 BoundMethodHandle.class.getClassLoader(), null)
581 .asSubclass(BoundMethodHandle.class);
582
583 return bmhClass;
584 }
585
586 static String speciesInternalClassName(String shortTypes) {
587 return SPECIES_PREFIX_PATH + shortTypes;
588 }
589
590 static byte[] generateConcreteBMHClassBytes(final String shortTypes,
591 final String types, final String className) {
592 final String sourceFile = SPECIES_PREFIX_NAME + shortTypes;
593
594 final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS + ClassWriter.COMPUTE_FRAMES);
595 final int NOT_ACC_PUBLIC = 0; // not ACC_PUBLIC
596 cw.visit(V1_6, NOT_ACC_PUBLIC + ACC_FINAL + ACC_SUPER, className, null, BMH, null);
597 cw.visitSource(sourceFile, null);
598
599 // emit static types and SPECIES_DATA fields
600 FieldVisitor fw = cw.visitField(NOT_ACC_PUBLIC + ACC_STATIC, "SPECIES_DATA", SPECIES_DATA_SIG, null, null);
601 fw.visitAnnotation(STABLE_SIG, true);
602 fw.visitEnd();
603
604 // emit bound argument fields
605 for (int i = 0; i < types.length(); ++i) {
606 final char t = types.charAt(i);
607 final String fieldName = makeFieldName(types, i);
608 final String fieldDesc = t == 'L' ? JLO_SIG : String.valueOf(t);
609 cw.visitField(ACC_FINAL, fieldName, fieldDesc, null, null).visitEnd();
610 }
611
612 MethodVisitor mv;
613
614 // emit constructor
615 mv = cw.visitMethod(ACC_PRIVATE, "<init>", makeSignature(types, true), null, null);
616 mv.visitCode();
617 mv.visitVarInsn(ALOAD, 0); // this
618 mv.visitVarInsn(ALOAD, 1); // type
619 mv.visitVarInsn(ALOAD, 2); // form
620
621 mv.visitMethodInsn(INVOKESPECIAL, BMH, "<init>", makeSignature("", true), false);
622
623 for (int i = 0, j = 0; i < types.length(); ++i, ++j) {
624 // i counts the arguments, j counts corresponding argument slots
625 char t = types.charAt(i);
626 mv.visitVarInsn(ALOAD, 0);
627 mv.visitVarInsn(typeLoadOp(t), j + 3); // parameters start at 3
628 mv.visitFieldInsn(PUTFIELD, className, makeFieldName(types, i), typeSig(t));
629 if (t == 'J' || t == 'D') {
630 ++j; // adjust argument register access
631 }
632 }
633
634 mv.visitInsn(RETURN);
635 mv.visitMaxs(0, 0);
636 mv.visitEnd();
637
638 // emit implementation of speciesData()
639 mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "speciesData", MYSPECIES_DATA_SIG, null, null);
640 mv.visitCode();
641 mv.visitFieldInsn(GETSTATIC, className, "SPECIES_DATA", SPECIES_DATA_SIG);
642 mv.visitInsn(ARETURN);
643 mv.visitMaxs(0, 0);
644 mv.visitEnd();
645
646 // emit implementation of fieldCount()
647 mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "fieldCount", INT_SIG, null, null);
648 mv.visitCode();
649 int fc = types.length();
650 if (fc <= (ICONST_5 - ICONST_0)) {
651 mv.visitInsn(ICONST_0 + fc);
652 } else {
653 mv.visitIntInsn(SIPUSH, fc);
654 }
655 mv.visitInsn(IRETURN);
656 mv.visitMaxs(0, 0);
657 mv.visitEnd();
658 // emit make() ...factory method wrapping constructor
659 mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_STATIC, "make", makeSignature(types, false), null, null);
660 mv.visitCode();
661 // make instance
662 mv.visitTypeInsn(NEW, className);
663 mv.visitInsn(DUP);
664 // load mt, lf
665 mv.visitVarInsn(ALOAD, 0); // type
666 mv.visitVarInsn(ALOAD, 1); // form
667 // load factory method arguments
668 for (int i = 0, j = 0; i < types.length(); ++i, ++j) {
669 // i counts the arguments, j counts corresponding argument slots
670 char t = types.charAt(i);
671 mv.visitVarInsn(typeLoadOp(t), j + 2); // parameters start at 3
672 if (t == 'J' || t == 'D') {
673 ++j; // adjust argument register access
674 }
675 }
676
677 // finally, invoke the constructor and return
678 mv.visitMethodInsn(INVOKESPECIAL, className, "<init>", makeSignature(types, true), false);
679 mv.visitInsn(ARETURN);
680 mv.visitMaxs(0, 0);
681 mv.visitEnd();
682
683 // emit copyWith()
684 mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "copyWith", makeSignature("", false), null, null);
685 mv.visitCode();
686 // make instance
687 mv.visitTypeInsn(NEW, className);
688 mv.visitInsn(DUP);
689 // load mt, lf
690 mv.visitVarInsn(ALOAD, 1);
691 mv.visitVarInsn(ALOAD, 2);
692 // put fields on the stack
693 emitPushFields(types, className, mv);
694 // finally, invoke the constructor and return
695 mv.visitMethodInsn(INVOKESPECIAL, className, "<init>", makeSignature(types, true), false);
696 mv.visitInsn(ARETURN);
697 mv.visitMaxs(0, 0);
698 mv.visitEnd();
699
700 // for each type, emit copyWithExtendT()
701 for (BasicType type : BasicType.ARG_TYPES) {
702 if (type == Q_TYPE) continue;
703 int ord = type.ordinal();
704 char btChar = type.basicTypeChar();
705 mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "copyWithExtend" + btChar, makeSignature(String.valueOf(btChar), false), null, E_THROWABLE);
706 mv.visitCode();
707 // return SPECIES_DATA.extendWith(t).constructor().invokeBasic(mt, lf, argL0, ..., narg)
708 // obtain constructor
709 mv.visitFieldInsn(GETSTATIC, className, "SPECIES_DATA", SPECIES_DATA_SIG);
710 int iconstInsn = ICONST_0 + ord;
711 assert(iconstInsn <= ICONST_5);
712 mv.visitInsn(iconstInsn);
713 mv.visitMethodInsn(INVOKEVIRTUAL, SPECIES_DATA, "extendWith", BMHSPECIES_DATA_EWI_SIG, false);
714 mv.visitMethodInsn(INVOKEVIRTUAL, SPECIES_DATA, "constructor", "()" + MH_SIG, false);
715 // load mt, lf
716 mv.visitVarInsn(ALOAD, 1);
717 mv.visitVarInsn(ALOAD, 2);
718 // put fields on the stack
719 emitPushFields(types, className, mv);
720 // put narg on stack
721 mv.visitVarInsn(typeLoadOp(btChar), 3);
722 // finally, invoke the constructor and return
723 mv.visitMethodInsn(INVOKEVIRTUAL, MH, "invokeBasic", makeSignature(types + btChar, false), false);
724 mv.visitInsn(ARETURN);
725 mv.visitMaxs(0, 0);
726 mv.visitEnd();
727 }
728
729 cw.visitEnd();
730
731 return cw.toByteArray();
732 }
733
734 private static int typeLoadOp(char t) {
735 switch (t) {
736 case 'L': return ALOAD;
737 case 'I': return ILOAD;
738 case 'J': return LLOAD;
739 case 'F': return FLOAD;
740 case 'D': return DLOAD;
741 default : throw newInternalError("unrecognized type " + t);
742 }
743 }
744
745 private static void emitPushFields(String types, String className, MethodVisitor mv) {
746 for (int i = 0; i < types.length(); ++i) {
747 char tc = types.charAt(i);
748 mv.visitVarInsn(ALOAD, 0);
749 mv.visitFieldInsn(GETFIELD, className, makeFieldName(types, i), typeSig(tc));
750 }
751 }
752
753 static String typeSig(char t) {
754 return t == 'L' ? JLO_SIG : String.valueOf(t);
755 }
756
757 //
758 // Getter MH generation.
759 //
760
761 private static MethodHandle makeGetter(Class<?> cbmhClass, String types, int index) {
762 String fieldName = makeFieldName(types, index);
763 Class<?> fieldType = Wrapper.forBasicType(types.charAt(index)).primitiveType();
764 try {
765 return LOOKUP.findGetter(cbmhClass, fieldName, fieldType);
766 } catch (NoSuchFieldException | IllegalAccessException e) {
767 throw newInternalError(e);
768 }
769 }
770
771 static MethodHandle[] makeGetters(Class<?> cbmhClass, String types, MethodHandle[] mhs) {
772 if (mhs == null) mhs = new MethodHandle[types.length()];
773 for (int i = 0; i < mhs.length; ++i) {
774 mhs[i] = makeGetter(cbmhClass, types, i);
775 assert(mhs[i].internalMemberName().getDeclaringClass() == cbmhClass);
776 }
777 return mhs;
778 }
779
780 static MethodHandle[] makeCtors(Class<? extends BoundMethodHandle> cbmh, String types, MethodHandle mhs[]) {
781 if (mhs == null) mhs = new MethodHandle[1];
782 if (types.equals("")) return mhs; // hack for empty BMH species
783 mhs[0] = makeCbmhCtor(cbmh, types);
784 return mhs;
785 }
786
787 static NamedFunction[] makeNominalGetters(String types, NamedFunction[] nfs, MethodHandle[] getters) {
788 if (nfs == null) nfs = new NamedFunction[types.length()];
789 for (int i = 0; i < nfs.length; ++i) {
790 nfs[i] = new NamedFunction(getters[i]);
791 }
792 return nfs;
793 }
794
795 //
796 // Auxiliary methods.
797 //
798
799 static SpeciesData getSpeciesDataFromConcreteBMHClass(Class<? extends BoundMethodHandle> cbmh) {
800 try {
801 Field F_SPECIES_DATA = cbmh.getDeclaredField("SPECIES_DATA");
802 return (SpeciesData) F_SPECIES_DATA.get(null);
803 } catch (ReflectiveOperationException ex) {
804 throw newInternalError(ex);
805 }
806 }
807
808 static void setSpeciesDataToConcreteBMHClass(Class<? extends BoundMethodHandle> cbmh, SpeciesData speciesData) {
809 try {
810 Field F_SPECIES_DATA = cbmh.getDeclaredField("SPECIES_DATA");
811 // ## FIXME: annotation parser can't create proxy classes until module system is fully initialzed
812 // assert F_SPECIES_DATA.getDeclaredAnnotation(Stable.class) != null;
813 F_SPECIES_DATA.set(null, speciesData);
814 } catch (ReflectiveOperationException ex) {
815 throw newInternalError(ex);
816 }
817 }
818
819 /**
820 * Field names in concrete BMHs adhere to this pattern:
821 * arg + type + index
822 * where type is a single character (L, I, J, F, D).
823 */
824 private static String makeFieldName(String types, int index) {
825 assert index >= 0 && index < types.length();
826 return "arg" + types.charAt(index) + index;
827 }
828
829 private static String makeSignature(String types, boolean ctor) {
830 StringBuilder buf = new StringBuilder(SIG_INCIPIT);
831 int len = types.length();
832 for (int i = 0; i < len; i++) {
833 buf.append(typeSig(types.charAt(i)));
834 }
835 return buf.append(')').append(ctor ? "V" : BMH_SIG).toString();
836 }
837
838 private static MethodType makeConstructorType(String types) {
839 int length = types.length();
840 Class<?> ptypes[] = new Class<?>[length + 2];
841 ptypes[0] = MethodType.class;
842 ptypes[1] = LambdaForm.class;
843 for (int i = 0; i < length; i++) {
844 ptypes[i + 2] = BasicType.basicType(types.charAt(i)).basicTypeClass();
845 }
846 return MethodType.makeImpl(BoundMethodHandle.class, ptypes, true);
847 }
848
849 static MethodHandle makeCbmhCtor(Class<? extends BoundMethodHandle> cbmh, String types) {
850 try {
851 return LOOKUP.findStatic(cbmh, "make", makeConstructorType(types));
852 } catch (NoSuchMethodException | IllegalAccessException | IllegalArgumentException | TypeNotPresentException e) {
853 throw newInternalError(e);
854 }
855 }
856 }
857
858 static final Lookup LOOKUP = Lookup.IMPL_LOOKUP;
859
860 /**
861 * All subclasses must provide such a value describing their type signature.
862 */
863 static final SpeciesData SPECIES_DATA = SpeciesData.EMPTY;
864
865 private static final SpeciesData[] SPECIES_DATA_CACHE = new SpeciesData[6];
866 private static SpeciesData checkCache(int size, String types) {
867 int idx = size - 1;
868 SpeciesData data = SPECIES_DATA_CACHE[idx];
869 if (data != null) return data;
870 SPECIES_DATA_CACHE[idx] = data = getSpeciesData(types);
871 return data;
872 }
873 static SpeciesData speciesData_L() { return checkCache(1, "L"); }
874 static SpeciesData speciesData_LL() { return checkCache(2, "LL"); }
875 static SpeciesData speciesData_LLL() { return checkCache(3, "LLL"); }
876 static SpeciesData speciesData_LLLL() { return checkCache(4, "LLLL"); }
877 static SpeciesData speciesData_LLLLL() { return checkCache(5, "LLLLL"); }
878 }