1 /*
2 * Copyright (c) 2008, 2013, 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 static jdk.internal.org.objectweb.asm.Opcodes.*;
29 import static java.lang.invoke.LambdaForm.*;
30 import static java.lang.invoke.LambdaForm.BasicType.*;
31 import static java.lang.invoke.MethodHandleStatics.*;
32
33 import java.lang.invoke.LambdaForm.NamedFunction;
34 import java.lang.invoke.MethodHandles.Lookup;
35 import java.lang.reflect.Field;
36 import java.util.Arrays;
37 import java.util.HashMap;
38
39 import sun.invoke.util.ValueConversions;
40 import sun.invoke.util.Wrapper;
41
42 import jdk.internal.org.objectweb.asm.ClassWriter;
43 import jdk.internal.org.objectweb.asm.MethodVisitor;
44 import jdk.internal.org.objectweb.asm.Type;
45
46 /**
47 * The flavor of method handle which emulates an invoke instruction
48 * on a predetermined argument. The JVM dispatches to the correct method
49 * when the handle is created, not when it is invoked.
50 *
51 * All bound arguments are encapsulated in dedicated species.
52 */
53 /* non-public */ abstract class BoundMethodHandle extends MethodHandle {
54
55 /* non-public */ BoundMethodHandle(MethodType type, LambdaForm form) {
56 super(type, form);
57 }
58
59 //
60 // BMH API and internals
61 //
62
63 static BoundMethodHandle bindSingle(MethodType type, LambdaForm form, BasicType xtype, Object x) {
64 // for some type signatures, there exist pre-defined concrete BMH classes
65 try {
66 switch (xtype) {
67 case L_TYPE:
68 return bindSingle(type, form, x); // Use known fast path.
69 case I_TYPE:
70 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(I_TYPE).constructor().invokeBasic(type, form, ValueConversions.widenSubword(x));
71 case J_TYPE:
72 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(J_TYPE).constructor().invokeBasic(type, form, (long) x);
73 case F_TYPE:
74 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(F_TYPE).constructor().invokeBasic(type, form, (float) x);
75 case D_TYPE:
76 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(D_TYPE).constructor().invokeBasic(type, form, (double) x);
77 default : throw newInternalError("unexpected xtype: " + xtype);
78 }
79 } catch (Throwable t) {
80 throw newInternalError(t);
81 }
82 }
83
84 static BoundMethodHandle bindSingle(MethodType type, LambdaForm form, Object x) {
85 return Species_L.make(type, form, x);
86 }
87
88 @Override // there is a default binder in the super class, for 'L' types only
89 /*non-public*/
90 BoundMethodHandle bindArgumentL(int pos, Object value) {
91 MethodType type = type().dropParameterTypes(pos, pos+1);
92 LambdaForm form = internalForm().bind(1+pos, speciesData());
93 return copyWithExtendL(type, form, value);
94 }
95 /*non-public*/
96 BoundMethodHandle bindArgumentI(int pos, int value) {
97 MethodType type = type().dropParameterTypes(pos, pos+1);
98 LambdaForm form = internalForm().bind(1+pos, speciesData());
99 return copyWithExtendI(type, form, value);
100 }
101 /*non-public*/
102 BoundMethodHandle bindArgumentJ(int pos, long value) {
103 MethodType type = type().dropParameterTypes(pos, pos+1);
104 LambdaForm form = internalForm().bind(1+pos, speciesData());
105 return copyWithExtendJ(type, form, value);
106 }
107 /*non-public*/
108 BoundMethodHandle bindArgumentF(int pos, float value) {
109 MethodType type = type().dropParameterTypes(pos, pos+1);
110 LambdaForm form = internalForm().bind(1+pos, speciesData());
111 return copyWithExtendF(type, form, value);
112 }
113 /*non-public*/
114 BoundMethodHandle bindArgumentD(int pos, double value) {
115 MethodType type = type().dropParameterTypes(pos, pos + 1);
116 LambdaForm form = internalForm().bind(1+pos, speciesData());
117 return copyWithExtendD(type, form, value);
118 }
119
120 @Override
121 BoundMethodHandle rebind() {
122 if (!tooComplex()) {
123 return this;
124 }
125 return makeReinvoker(this);
126 }
127
128 private boolean tooComplex() {
129 return (fieldCount() > FIELD_COUNT_THRESHOLD ||
130 form.expressionCount() > FORM_EXPRESSION_THRESHOLD);
131 }
132 private static int FIELD_COUNT_THRESHOLD = 12; // largest convenient BMH field count
133 private static int FORM_EXPRESSION_THRESHOLD = 24; // largest convenient BMH expression count
134
135 /**
136 * A reinvoker MH has this form:
137 * {@code lambda (bmh, arg*) { thismh = bmh[0]; invokeBasic(thismh, arg*) }}
138 */
139 static BoundMethodHandle makeReinvoker(MethodHandle target) {
140 LambdaForm form = DelegatingMethodHandle.makeReinvokerForm(
141 target, MethodTypeForm.LF_REBIND, Species_L.SPECIES_DATA.getterFunction(0) );
142 return Species_L.make(target.type(), form, target);
143 }
144
145 /**
146 * Return the {@link SpeciesData} instance representing this BMH species. All subclasses must provide a
147 * static field containing this value, and they must accordingly implement this method.
148 */
149 /*non-public*/ abstract SpeciesData speciesData();
150
151 /**
152 * Return the number of fields in this BMH. Equivalent to speciesData().fieldCount().
153 */
154 /*non-public*/ abstract int fieldCount();
155
156 @Override
157 Object internalProperties() {
158 return "\n& BMH="+internalValues();
159 }
160
161 @Override
162 final Object internalValues() {
163 Object[] boundValues = new Object[speciesData().fieldCount()];
164 for (int i = 0; i < boundValues.length; ++i) {
165 boundValues[i] = arg(i);
166 }
167 return Arrays.asList(boundValues);
168 }
169
170 /*non-public*/ final Object arg(int i) {
171 try {
172 switch (speciesData().fieldType(i)) {
173 case L_TYPE: return speciesData().getters[i].invokeBasic(this);
174 case I_TYPE: return (int) speciesData().getters[i].invokeBasic(this);
175 case J_TYPE: return (long) speciesData().getters[i].invokeBasic(this);
176 case F_TYPE: return (float) speciesData().getters[i].invokeBasic(this);
177 case D_TYPE: return (double) speciesData().getters[i].invokeBasic(this);
178 }
179 } catch (Throwable ex) {
180 throw newInternalError(ex);
181 }
182 throw new InternalError("unexpected type: " + speciesData().typeChars+"."+i);
183 }
184
185 //
186 // cloning API
187 //
188
189 /*non-public*/ abstract BoundMethodHandle copyWith(MethodType mt, LambdaForm lf);
190 /*non-public*/ abstract BoundMethodHandle copyWithExtendL(MethodType mt, LambdaForm lf, Object narg);
191 /*non-public*/ abstract BoundMethodHandle copyWithExtendI(MethodType mt, LambdaForm lf, int narg);
192 /*non-public*/ abstract BoundMethodHandle copyWithExtendJ(MethodType mt, LambdaForm lf, long narg);
193 /*non-public*/ abstract BoundMethodHandle copyWithExtendF(MethodType mt, LambdaForm lf, float narg);
194 /*non-public*/ abstract BoundMethodHandle copyWithExtendD(MethodType mt, LambdaForm lf, double narg);
195
196 //
197 // concrete BMH classes required to close bootstrap loops
198 //
199
200 private // make it private to force users to access the enclosing class first
201 static final class Species_L extends BoundMethodHandle {
202 final Object argL0;
203 private Species_L(MethodType mt, LambdaForm lf, Object argL0) {
204 super(mt, lf);
205 this.argL0 = argL0;
206 }
207 @Override
208 /*non-public*/ SpeciesData speciesData() {
209 return SPECIES_DATA;
210 }
211 @Override
212 /*non-public*/ int fieldCount() {
213 return 1;
214 }
215 /*non-public*/ static final SpeciesData SPECIES_DATA = SpeciesData.getForClass("L", Species_L.class);
216 /*non-public*/ static BoundMethodHandle make(MethodType mt, LambdaForm lf, Object argL0) {
217 return new Species_L(mt, lf, argL0);
218 }
219 @Override
220 /*non-public*/ final BoundMethodHandle copyWith(MethodType mt, LambdaForm lf) {
221 return new Species_L(mt, lf, argL0);
222 }
223 @Override
224 /*non-public*/ final BoundMethodHandle copyWithExtendL(MethodType mt, LambdaForm lf, Object narg) {
225 try {
226 return (BoundMethodHandle) SPECIES_DATA.extendWith(L_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);
227 } catch (Throwable ex) {
228 throw uncaughtException(ex);
229 }
230 }
231 @Override
232 /*non-public*/ final BoundMethodHandle copyWithExtendI(MethodType mt, LambdaForm lf, int narg) {
233 try {
234 return (BoundMethodHandle) SPECIES_DATA.extendWith(I_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);
235 } catch (Throwable ex) {
236 throw uncaughtException(ex);
237 }
238 }
239 @Override
240 /*non-public*/ final BoundMethodHandle copyWithExtendJ(MethodType mt, LambdaForm lf, long narg) {
241 try {
242 return (BoundMethodHandle) SPECIES_DATA.extendWith(J_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);
243 } catch (Throwable ex) {
244 throw uncaughtException(ex);
245 }
246 }
247 @Override
248 /*non-public*/ final BoundMethodHandle copyWithExtendF(MethodType mt, LambdaForm lf, float narg) {
249 try {
250 return (BoundMethodHandle) SPECIES_DATA.extendWith(F_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);
251 } catch (Throwable ex) {
252 throw uncaughtException(ex);
253 }
254 }
255 @Override
256 /*non-public*/ final BoundMethodHandle copyWithExtendD(MethodType mt, LambdaForm lf, double narg) {
257 try {
258 return (BoundMethodHandle) SPECIES_DATA.extendWith(D_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);
259 } catch (Throwable ex) {
260 throw uncaughtException(ex);
261 }
262 }
263 }
264
265 //
266 // BMH species meta-data
267 //
268
269 /**
270 * Meta-data wrapper for concrete BMH types.
271 * Each BMH type corresponds to a given sequence of basic field types (LIJFD).
272 * The fields are immutable; their values are fully specified at object construction.
273 * Each BMH type supplies an array of getter functions which may be used in lambda forms.
274 * A BMH is constructed by cloning a shorter BMH and adding one or more new field values.
275 * As a degenerate and common case, the "shorter BMH" can be missing, and contributes zero prior fields.
276 */
277 static class SpeciesData {
278 final String typeChars;
279 final BasicType[] typeCodes;
280 final Class<? extends BoundMethodHandle> clazz;
281 // Bootstrapping requires circular relations MH -> BMH -> SpeciesData -> MH
282 // Therefore, we need a non-final link in the chain. Use array elements.
283 final MethodHandle[] constructor;
284 final MethodHandle[] getters;
285 final NamedFunction[] nominalGetters;
286 final SpeciesData[] extensions;
287
288 /*non-public*/ int fieldCount() {
289 return typeCodes.length;
290 }
291 /*non-public*/ BasicType fieldType(int i) {
292 return typeCodes[i];
293 }
294 /*non-public*/ char fieldTypeChar(int i) {
295 return typeChars.charAt(i);
296 }
297
298 public String toString() {
299 return "SpeciesData["+(isPlaceholder() ? "<placeholder>" : clazz.getSimpleName())+":"+typeChars+"]";
300 }
301
302 /**
303 * Return a {@link LambdaForm.Name} containing a {@link LambdaForm.NamedFunction} that
304 * represents a MH bound to a generic invoker, which in turn forwards to the corresponding
305 * getter.
306 */
307 NamedFunction getterFunction(int i) {
308 return nominalGetters[i];
309 }
310
311 MethodHandle constructor() {
312 return constructor[0];
313 }
314
315 static final SpeciesData EMPTY = new SpeciesData("", BoundMethodHandle.class);
316
317 private SpeciesData(String types, Class<? extends BoundMethodHandle> clazz) {
318 this.typeChars = types;
319 this.typeCodes = basicTypes(types);
320 this.clazz = clazz;
321 if (!INIT_DONE) {
322 this.constructor = new MethodHandle[1]; // only one ctor
323 this.getters = new MethodHandle[types.length()];
324 this.nominalGetters = new NamedFunction[types.length()];
325 } else {
326 this.constructor = Factory.makeCtors(clazz, types, null);
327 this.getters = Factory.makeGetters(clazz, types, null);
328 this.nominalGetters = Factory.makeNominalGetters(types, null, this.getters);
329 }
330 this.extensions = new SpeciesData[ARG_TYPE_LIMIT];
331 }
332
333 private void initForBootstrap() {
334 assert(!INIT_DONE);
335 if (constructor() == null) {
336 String types = typeChars;
337 Factory.makeCtors(clazz, types, this.constructor);
338 Factory.makeGetters(clazz, types, this.getters);
339 Factory.makeNominalGetters(types, this.nominalGetters, this.getters);
340 }
341 }
342
343 private SpeciesData(String typeChars) {
344 // Placeholder only.
345 this.typeChars = typeChars;
346 this.typeCodes = basicTypes(typeChars);
347 this.clazz = null;
348 this.constructor = null;
349 this.getters = null;
350 this.nominalGetters = null;
351 this.extensions = null;
352 }
353 private boolean isPlaceholder() { return clazz == null; }
354
355 private static final HashMap<String, SpeciesData> CACHE = new HashMap<>();
356 static { CACHE.put("", EMPTY); } // make bootstrap predictable
357 private static final boolean INIT_DONE; // set after <clinit> finishes...
358
359 SpeciesData extendWith(byte type) {
360 return extendWith(BasicType.basicType(type));
361 }
362
363 SpeciesData extendWith(BasicType type) {
364 int ord = type.ordinal();
365 SpeciesData d = extensions[ord];
366 if (d != null) return d;
367 extensions[ord] = d = get(typeChars+type.basicTypeChar());
368 return d;
369 }
370
371 private static SpeciesData get(String types) {
372 // Acquire cache lock for query.
373 SpeciesData d = lookupCache(types);
374 if (!d.isPlaceholder())
375 return d;
376 synchronized (d) {
377 // Use synch. on the placeholder to prevent multiple instantiation of one species.
378 // Creating this class forces a recursive call to getForClass.
379 if (lookupCache(types).isPlaceholder())
380 Factory.generateConcreteBMHClass(types);
381 }
382 // Reacquire cache lock.
383 d = lookupCache(types);
384 // Class loading must have upgraded the cache.
385 assert(d != null && !d.isPlaceholder());
386 return d;
387 }
388 static SpeciesData getForClass(String types, Class<? extends BoundMethodHandle> clazz) {
389 // clazz is a new class which is initializing its SPECIES_DATA field
390 return updateCache(types, new SpeciesData(types, clazz));
391 }
392 private static synchronized SpeciesData lookupCache(String types) {
393 SpeciesData d = CACHE.get(types);
394 if (d != null) return d;
395 d = new SpeciesData(types);
396 assert(d.isPlaceholder());
397 CACHE.put(types, d);
398 return d;
399 }
400 private static synchronized SpeciesData updateCache(String types, SpeciesData d) {
401 SpeciesData d2;
402 assert((d2 = CACHE.get(types)) == null || d2.isPlaceholder());
403 assert(!d.isPlaceholder());
404 CACHE.put(types, d);
405 return d;
406 }
407
408 static {
409 // pre-fill the BMH speciesdata cache with BMH's inner classes
410 final Class<BoundMethodHandle> rootCls = BoundMethodHandle.class;
411 try {
412 for (Class<?> c : rootCls.getDeclaredClasses()) {
413 if (rootCls.isAssignableFrom(c)) {
414 final Class<? extends BoundMethodHandle> cbmh = c.asSubclass(BoundMethodHandle.class);
415 SpeciesData d = Factory.speciesDataFromConcreteBMHClass(cbmh);
416 assert(d != null) : cbmh.getName();
417 assert(d.clazz == cbmh);
418 assert(d == lookupCache(d.typeChars));
419 }
420 }
421 } catch (Throwable e) {
422 throw newInternalError(e);
423 }
424
425 for (SpeciesData d : CACHE.values()) {
426 d.initForBootstrap();
427 }
428 // Note: Do not simplify this, because INIT_DONE must not be
429 // a compile-time constant during bootstrapping.
430 INIT_DONE = Boolean.TRUE;
431 }
432 }
433
434 static SpeciesData getSpeciesData(String types) {
435 return SpeciesData.get(types);
436 }
437
438 /**
439 * Generation of concrete BMH classes.
440 *
441 * A concrete BMH species is fit for binding a number of values adhering to a
442 * given type pattern. Reference types are erased.
443 *
444 * BMH species are cached by type pattern.
445 *
446 * A BMH species has a number of fields with the concrete (possibly erased) types of
447 * bound values. Setters are provided as an API in BMH. Getters are exposed as MHs,
448 * which can be included as names in lambda forms.
449 */
450 static class Factory {
451
452 static final String JLO_SIG = "Ljava/lang/Object;";
453 static final String JLS_SIG = "Ljava/lang/String;";
454 static final String JLC_SIG = "Ljava/lang/Class;";
455 static final String MH = "java/lang/invoke/MethodHandle";
456 static final String MH_SIG = "L"+MH+";";
457 static final String BMH = "java/lang/invoke/BoundMethodHandle";
458 static final String BMH_SIG = "L"+BMH+";";
459 static final String SPECIES_DATA = "java/lang/invoke/BoundMethodHandle$SpeciesData";
460 static final String SPECIES_DATA_SIG = "L"+SPECIES_DATA+";";
461
462 static final String SPECIES_PREFIX_NAME = "Species_";
463 static final String SPECIES_PREFIX_PATH = BMH + "$" + SPECIES_PREFIX_NAME;
464
465 static final String BMHSPECIES_DATA_EWI_SIG = "(B)" + SPECIES_DATA_SIG;
466 static final String BMHSPECIES_DATA_GFC_SIG = "(" + JLS_SIG + JLC_SIG + ")" + SPECIES_DATA_SIG;
467 static final String MYSPECIES_DATA_SIG = "()" + SPECIES_DATA_SIG;
468 static final String VOID_SIG = "()V";
469 static final String INT_SIG = "()I";
470
471 static final String SIG_INCIPIT = "(Ljava/lang/invoke/MethodType;Ljava/lang/invoke/LambdaForm;";
472
473 static final String[] E_THROWABLE = new String[] { "java/lang/Throwable" };
474
475 /**
476 * Generate a concrete subclass of BMH for a given combination of bound types.
477 *
478 * A concrete BMH species adheres to the following schema:
479 *
480 * <pre>
481 * class Species_[[types]] extends BoundMethodHandle {
482 * [[fields]]
483 * final SpeciesData speciesData() { return SpeciesData.get("[[types]]"); }
484 * }
485 * </pre>
486 *
487 * The {@code [[types]]} signature is precisely the string that is passed to this
488 * method.
489 *
490 * The {@code [[fields]]} section consists of one field definition per character in
491 * the type signature, adhering to the naming schema described in the definition of
492 * {@link #makeFieldName}.
493 *
494 * For example, a concrete BMH species for two reference and one integral bound values
495 * would have the following shape:
496 *
497 * <pre>
498 * class BoundMethodHandle { ... private static
499 * final class Species_LLI extends BoundMethodHandle {
500 * final Object argL0;
501 * final Object argL1;
502 * final int argI2;
503 * private Species_LLI(MethodType mt, LambdaForm lf, Object argL0, Object argL1, int argI2) {
504 * super(mt, lf);
505 * this.argL0 = argL0;
506 * this.argL1 = argL1;
507 * this.argI2 = argI2;
508 * }
509 * final SpeciesData speciesData() { return SPECIES_DATA; }
510 * final int fieldCount() { return 3; }
511 * static final SpeciesData SPECIES_DATA = SpeciesData.getForClass("LLI", Species_LLI.class);
512 * static BoundMethodHandle make(MethodType mt, LambdaForm lf, Object argL0, Object argL1, int argI2) {
513 * return new Species_LLI(mt, lf, argL0, argL1, argI2);
514 * }
515 * final BoundMethodHandle copyWith(MethodType mt, LambdaForm lf) {
516 * return new Species_LLI(mt, lf, argL0, argL1, argI2);
517 * }
518 * final BoundMethodHandle copyWithExtendL(MethodType mt, LambdaForm lf, Object narg) {
519 * return SPECIES_DATA.extendWith(L_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);
520 * }
521 * final BoundMethodHandle copyWithExtendI(MethodType mt, LambdaForm lf, int narg) {
522 * return SPECIES_DATA.extendWith(I_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);
523 * }
524 * final BoundMethodHandle copyWithExtendJ(MethodType mt, LambdaForm lf, long narg) {
525 * return SPECIES_DATA.extendWith(J_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);
526 * }
527 * final BoundMethodHandle copyWithExtendF(MethodType mt, LambdaForm lf, float narg) {
528 * return SPECIES_DATA.extendWith(F_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);
529 * }
530 * public final BoundMethodHandle copyWithExtendD(MethodType mt, LambdaForm lf, double narg) {
531 * return SPECIES_DATA.extendWith(D_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);
532 * }
533 * }
534 * </pre>
535 *
536 * @param types the type signature, wherein reference types are erased to 'L'
537 * @return the generated concrete BMH class
538 */
539 static Class<? extends BoundMethodHandle> generateConcreteBMHClass(String types) {
540 final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS + ClassWriter.COMPUTE_FRAMES);
541
542 String shortTypes = LambdaForm.shortenSignature(types);
543 final String className = SPECIES_PREFIX_PATH + shortTypes;
544 final String sourceFile = SPECIES_PREFIX_NAME + shortTypes;
545 final int NOT_ACC_PUBLIC = 0; // not ACC_PUBLIC
546 cw.visit(V1_6, NOT_ACC_PUBLIC + ACC_FINAL + ACC_SUPER, className, null, BMH, null);
547 cw.visitSource(sourceFile, null);
548
549 // emit static types and SPECIES_DATA fields
550 cw.visitField(NOT_ACC_PUBLIC + ACC_STATIC, "SPECIES_DATA", SPECIES_DATA_SIG, null, null).visitEnd();
551
552 // emit bound argument fields
553 for (int i = 0; i < types.length(); ++i) {
554 final char t = types.charAt(i);
555 final String fieldName = makeFieldName(types, i);
556 final String fieldDesc = t == 'L' ? JLO_SIG : String.valueOf(t);
557 cw.visitField(ACC_FINAL, fieldName, fieldDesc, null, null).visitEnd();
558 }
559
560 MethodVisitor mv;
561
562 // emit constructor
563 mv = cw.visitMethod(ACC_PRIVATE, "<init>", makeSignature(types, true), null, null);
564 mv.visitCode();
565 mv.visitVarInsn(ALOAD, 0); // this
566 mv.visitVarInsn(ALOAD, 1); // type
567 mv.visitVarInsn(ALOAD, 2); // form
568
569 mv.visitMethodInsn(INVOKESPECIAL, BMH, "<init>", makeSignature("", true), false);
570
571 for (int i = 0, j = 0; i < types.length(); ++i, ++j) {
572 // i counts the arguments, j counts corresponding argument slots
573 char t = types.charAt(i);
574 mv.visitVarInsn(ALOAD, 0);
575 mv.visitVarInsn(typeLoadOp(t), j + 3); // parameters start at 3
576 mv.visitFieldInsn(PUTFIELD, className, makeFieldName(types, i), typeSig(t));
577 if (t == 'J' || t == 'D') {
578 ++j; // adjust argument register access
579 }
580 }
581
582 mv.visitInsn(RETURN);
583 mv.visitMaxs(0, 0);
584 mv.visitEnd();
585
586 // emit implementation of speciesData()
587 mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "speciesData", MYSPECIES_DATA_SIG, null, null);
588 mv.visitCode();
589 mv.visitFieldInsn(GETSTATIC, className, "SPECIES_DATA", SPECIES_DATA_SIG);
590 mv.visitInsn(ARETURN);
591 mv.visitMaxs(0, 0);
592 mv.visitEnd();
593
594 // emit implementation of fieldCount()
595 mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "fieldCount", INT_SIG, null, null);
596 mv.visitCode();
597 int fc = types.length();
598 if (fc <= (ICONST_5 - ICONST_0)) {
599 mv.visitInsn(ICONST_0 + fc);
600 } else {
601 mv.visitIntInsn(SIPUSH, fc);
602 }
603 mv.visitInsn(IRETURN);
604 mv.visitMaxs(0, 0);
605 mv.visitEnd();
606 // emit make() ...factory method wrapping constructor
607 mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_STATIC, "make", makeSignature(types, false), null, null);
608 mv.visitCode();
609 // make instance
610 mv.visitTypeInsn(NEW, className);
611 mv.visitInsn(DUP);
612 // load mt, lf
613 mv.visitVarInsn(ALOAD, 0); // type
614 mv.visitVarInsn(ALOAD, 1); // form
615 // load factory method arguments
616 for (int i = 0, j = 0; i < types.length(); ++i, ++j) {
617 // i counts the arguments, j counts corresponding argument slots
618 char t = types.charAt(i);
619 mv.visitVarInsn(typeLoadOp(t), j + 2); // parameters start at 3
620 if (t == 'J' || t == 'D') {
621 ++j; // adjust argument register access
622 }
623 }
624
625 // finally, invoke the constructor and return
626 mv.visitMethodInsn(INVOKESPECIAL, className, "<init>", makeSignature(types, true), false);
627 mv.visitInsn(ARETURN);
628 mv.visitMaxs(0, 0);
629 mv.visitEnd();
630
631 // emit copyWith()
632 mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "copyWith", makeSignature("", false), null, null);
633 mv.visitCode();
634 // make instance
635 mv.visitTypeInsn(NEW, className);
636 mv.visitInsn(DUP);
637 // load mt, lf
638 mv.visitVarInsn(ALOAD, 1);
639 mv.visitVarInsn(ALOAD, 2);
640 // put fields on the stack
641 emitPushFields(types, className, mv);
642 // finally, invoke the constructor and return
643 mv.visitMethodInsn(INVOKESPECIAL, className, "<init>", makeSignature(types, true), false);
644 mv.visitInsn(ARETURN);
645 mv.visitMaxs(0, 0);
646 mv.visitEnd();
647
648 // for each type, emit copyWithExtendT()
649 for (BasicType type : BasicType.ARG_TYPES) {
650 int ord = type.ordinal();
651 char btChar = type.basicTypeChar();
652 mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "copyWithExtend" + btChar, makeSignature(String.valueOf(btChar), false), null, E_THROWABLE);
653 mv.visitCode();
654 // return SPECIES_DATA.extendWith(t).constructor().invokeBasic(mt, lf, argL0, ..., narg)
655 // obtain constructor
656 mv.visitFieldInsn(GETSTATIC, className, "SPECIES_DATA", SPECIES_DATA_SIG);
657 int iconstInsn = ICONST_0 + ord;
658 assert(iconstInsn <= ICONST_5);
659 mv.visitInsn(iconstInsn);
660 mv.visitMethodInsn(INVOKEVIRTUAL, SPECIES_DATA, "extendWith", BMHSPECIES_DATA_EWI_SIG, false);
661 mv.visitMethodInsn(INVOKEVIRTUAL, SPECIES_DATA, "constructor", "()" + MH_SIG, false);
662 // load mt, lf
663 mv.visitVarInsn(ALOAD, 1);
664 mv.visitVarInsn(ALOAD, 2);
665 // put fields on the stack
666 emitPushFields(types, className, mv);
667 // put narg on stack
668 mv.visitVarInsn(typeLoadOp(btChar), 3);
669 // finally, invoke the constructor and return
670 mv.visitMethodInsn(INVOKEVIRTUAL, MH, "invokeBasic", makeSignature(types + btChar, false), false);
671 mv.visitInsn(ARETURN);
672 mv.visitMaxs(0, 0);
673 mv.visitEnd();
674 }
675
676 // emit class initializer
677 mv = cw.visitMethod(NOT_ACC_PUBLIC | ACC_STATIC, "<clinit>", VOID_SIG, null, null);
678 mv.visitCode();
679 mv.visitLdcInsn(types);
680 mv.visitLdcInsn(Type.getObjectType(className));
681 mv.visitMethodInsn(INVOKESTATIC, SPECIES_DATA, "getForClass", BMHSPECIES_DATA_GFC_SIG, false);
682 mv.visitFieldInsn(PUTSTATIC, className, "SPECIES_DATA", SPECIES_DATA_SIG);
683 mv.visitInsn(RETURN);
684 mv.visitMaxs(0, 0);
685 mv.visitEnd();
686
687 cw.visitEnd();
688
689 // load class
690 final byte[] classFile = cw.toByteArray();
691 InvokerBytecodeGenerator.maybeDump(className, classFile);
692 Class<? extends BoundMethodHandle> bmhClass =
693 //UNSAFE.defineAnonymousClass(BoundMethodHandle.class, classFile, null).asSubclass(BoundMethodHandle.class);
694 UNSAFE.defineClass(className, classFile, 0, classFile.length,
695 BoundMethodHandle.class.getClassLoader(), null)
696 .asSubclass(BoundMethodHandle.class);
697 UNSAFE.ensureClassInitialized(bmhClass);
698
699 return bmhClass;
700 }
701
702 private static int typeLoadOp(char t) {
703 switch (t) {
704 case 'L': return ALOAD;
705 case 'I': return ILOAD;
706 case 'J': return LLOAD;
707 case 'F': return FLOAD;
708 case 'D': return DLOAD;
709 default : throw newInternalError("unrecognized type " + t);
710 }
711 }
712
713 private static void emitPushFields(String types, String className, MethodVisitor mv) {
714 for (int i = 0; i < types.length(); ++i) {
715 char tc = types.charAt(i);
716 mv.visitVarInsn(ALOAD, 0);
717 mv.visitFieldInsn(GETFIELD, className, makeFieldName(types, i), typeSig(tc));
718 }
719 }
720
721 static String typeSig(char t) {
722 return t == 'L' ? JLO_SIG : String.valueOf(t);
723 }
724
725 //
726 // Getter MH generation.
727 //
728
729 private static MethodHandle makeGetter(Class<?> cbmhClass, String types, int index) {
730 String fieldName = makeFieldName(types, index);
731 Class<?> fieldType = Wrapper.forBasicType(types.charAt(index)).primitiveType();
732 try {
733 return LOOKUP.findGetter(cbmhClass, fieldName, fieldType);
734 } catch (NoSuchFieldException | IllegalAccessException e) {
735 throw newInternalError(e);
736 }
737 }
738
739 static MethodHandle[] makeGetters(Class<?> cbmhClass, String types, MethodHandle[] mhs) {
740 if (mhs == null) mhs = new MethodHandle[types.length()];
741 for (int i = 0; i < mhs.length; ++i) {
742 mhs[i] = makeGetter(cbmhClass, types, i);
743 assert(mhs[i].internalMemberName().getDeclaringClass() == cbmhClass);
744 }
745 return mhs;
746 }
747
748 static MethodHandle[] makeCtors(Class<? extends BoundMethodHandle> cbmh, String types, MethodHandle mhs[]) {
749 if (mhs == null) mhs = new MethodHandle[1];
750 if (types.equals("")) return mhs; // hack for empty BMH species
751 mhs[0] = makeCbmhCtor(cbmh, types);
752 return mhs;
753 }
754
755 static NamedFunction[] makeNominalGetters(String types, NamedFunction[] nfs, MethodHandle[] getters) {
756 if (nfs == null) nfs = new NamedFunction[types.length()];
757 for (int i = 0; i < nfs.length; ++i) {
758 nfs[i] = new NamedFunction(getters[i]);
759 }
760 return nfs;
761 }
762
763 //
764 // Auxiliary methods.
765 //
766
767 static SpeciesData speciesDataFromConcreteBMHClass(Class<? extends BoundMethodHandle> cbmh) {
768 try {
769 Field F_SPECIES_DATA = cbmh.getDeclaredField("SPECIES_DATA");
770 return (SpeciesData) F_SPECIES_DATA.get(null);
771 } catch (ReflectiveOperationException ex) {
772 throw newInternalError(ex);
773 }
774 }
775
776 /**
777 * Field names in concrete BMHs adhere to this pattern:
778 * arg + type + index
779 * where type is a single character (L, I, J, F, D).
780 */
781 private static String makeFieldName(String types, int index) {
782 assert index >= 0 && index < types.length();
783 return "arg" + types.charAt(index) + index;
784 }
785
786 private static String makeSignature(String types, boolean ctor) {
787 StringBuilder buf = new StringBuilder(SIG_INCIPIT);
788 for (char c : types.toCharArray()) {
789 buf.append(typeSig(c));
790 }
791 return buf.append(')').append(ctor ? "V" : BMH_SIG).toString();
792 }
793
794 static MethodHandle makeCbmhCtor(Class<? extends BoundMethodHandle> cbmh, String types) {
795 try {
796 return LOOKUP.findStatic(cbmh, "make", MethodType.fromMethodDescriptorString(makeSignature(types, false), null));
797 } catch (NoSuchMethodException | IllegalAccessException | IllegalArgumentException | TypeNotPresentException e) {
798 throw newInternalError(e);
799 }
800 }
801 }
802
803 private static final Lookup LOOKUP = Lookup.IMPL_LOOKUP;
804
805 /**
806 * All subclasses must provide such a value describing their type signature.
807 */
808 static final SpeciesData SPECIES_DATA = SpeciesData.EMPTY;
809
810 private static final SpeciesData[] SPECIES_DATA_CACHE = new SpeciesData[5];
811 private static SpeciesData checkCache(int size, String types) {
812 int idx = size - 1;
813 SpeciesData data = SPECIES_DATA_CACHE[idx];
814 if (data != null) return data;
815 SPECIES_DATA_CACHE[idx] = data = getSpeciesData(types);
816 return data;
817 }
818 static SpeciesData speciesData_L() { return checkCache(1, "L"); }
819 static SpeciesData speciesData_LL() { return checkCache(2, "LL"); }
820 static SpeciesData speciesData_LLL() { return checkCache(3, "LLL"); }
821 static SpeciesData speciesData_LLLL() { return checkCache(4, "LLLL"); }
822 static SpeciesData speciesData_LLLLL() { return checkCache(5, "LLLLL"); }
823 }