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 final int FIELD_COUNT_THRESHOLD = 12; // largest convenient BMH field count
133 private static final 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,
142 Species_L.SPECIES_DATA, Species_L.SPECIES_DATA.getterFunction(0));
143 return Species_L.make(target.type(), form, target);
144 }
145
146 /**
147 * Return the {@link SpeciesData} instance representing this BMH species. All subclasses must provide a
148 * static field containing this value, and they must accordingly implement this method.
149 */
150 /*non-public*/ abstract SpeciesData speciesData();
151
152 /**
153 * Return the number of fields in this BMH. Equivalent to speciesData().fieldCount().
154 */
155 /*non-public*/ abstract int fieldCount();
156
157 @Override
158 Object internalProperties() {
159 return "\n& BMH="+internalValues();
160 }
161
162 @Override
163 final Object internalValues() {
164 Object[] boundValues = new Object[speciesData().fieldCount()];
165 for (int i = 0; i < boundValues.length; ++i) {
166 boundValues[i] = arg(i);
167 }
168 return Arrays.asList(boundValues);
169 }
170
171 /*non-public*/ final Object arg(int i) {
172 try {
173 switch (speciesData().fieldType(i)) {
174 case L_TYPE: return speciesData().getters[i].invokeBasic(this);
175 case I_TYPE: return (int) speciesData().getters[i].invokeBasic(this);
176 case J_TYPE: return (long) speciesData().getters[i].invokeBasic(this);
177 case F_TYPE: return (float) speciesData().getters[i].invokeBasic(this);
178 case D_TYPE: return (double) speciesData().getters[i].invokeBasic(this);
179 }
180 } catch (Throwable ex) {
181 throw newInternalError(ex);
182 }
183 throw new InternalError("unexpected type: " + speciesData().typeChars+"."+i);
184 }
185
186 //
187 // cloning API
188 //
189
190 /*non-public*/ abstract BoundMethodHandle copyWith(MethodType mt, LambdaForm lf);
191 /*non-public*/ abstract BoundMethodHandle copyWithExtendL(MethodType mt, LambdaForm lf, Object narg);
192 /*non-public*/ abstract BoundMethodHandle copyWithExtendI(MethodType mt, LambdaForm lf, int narg);
193 /*non-public*/ abstract BoundMethodHandle copyWithExtendJ(MethodType mt, LambdaForm lf, long narg);
194 /*non-public*/ abstract BoundMethodHandle copyWithExtendF(MethodType mt, LambdaForm lf, float narg);
195 /*non-public*/ abstract BoundMethodHandle copyWithExtendD(MethodType mt, LambdaForm lf, double narg);
196
197 //
198 // concrete BMH classes required to close bootstrap loops
199 //
200
201 private // make it private to force users to access the enclosing class first
202 static final class Species_L extends BoundMethodHandle {
203 final Object argL0;
204 private Species_L(MethodType mt, LambdaForm lf, Object argL0) {
205 super(mt, lf);
206 this.argL0 = argL0;
207 }
208 @Override
209 /*non-public*/ SpeciesData speciesData() {
210 return SPECIES_DATA;
211 }
212 @Override
213 /*non-public*/ int fieldCount() {
214 return 1;
215 }
216 /*non-public*/ static final SpeciesData SPECIES_DATA = SpeciesData.getForClass("L", Species_L.class);
217 /*non-public*/ static BoundMethodHandle make(MethodType mt, LambdaForm lf, Object argL0) {
218 return new Species_L(mt, lf, argL0);
219 }
220 @Override
221 /*non-public*/ final BoundMethodHandle copyWith(MethodType mt, LambdaForm lf) {
222 return new Species_L(mt, lf, argL0);
223 }
224 @Override
225 /*non-public*/ final BoundMethodHandle copyWithExtendL(MethodType mt, LambdaForm lf, Object narg) {
226 try {
227 return (BoundMethodHandle) SPECIES_DATA.extendWith(L_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);
228 } catch (Throwable ex) {
229 throw uncaughtException(ex);
230 }
231 }
232 @Override
233 /*non-public*/ final BoundMethodHandle copyWithExtendI(MethodType mt, LambdaForm lf, int narg) {
234 try {
235 return (BoundMethodHandle) SPECIES_DATA.extendWith(I_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);
236 } catch (Throwable ex) {
237 throw uncaughtException(ex);
238 }
239 }
240 @Override
241 /*non-public*/ final BoundMethodHandle copyWithExtendJ(MethodType mt, LambdaForm lf, long narg) {
242 try {
243 return (BoundMethodHandle) SPECIES_DATA.extendWith(J_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);
244 } catch (Throwable ex) {
245 throw uncaughtException(ex);
246 }
247 }
248 @Override
249 /*non-public*/ final BoundMethodHandle copyWithExtendF(MethodType mt, LambdaForm lf, float narg) {
250 try {
251 return (BoundMethodHandle) SPECIES_DATA.extendWith(F_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);
252 } catch (Throwable ex) {
253 throw uncaughtException(ex);
254 }
255 }
256 @Override
257 /*non-public*/ final BoundMethodHandle copyWithExtendD(MethodType mt, LambdaForm lf, double narg) {
258 try {
259 return (BoundMethodHandle) SPECIES_DATA.extendWith(D_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);
260 } catch (Throwable ex) {
261 throw uncaughtException(ex);
262 }
263 }
264 }
265
266 //
267 // BMH species meta-data
268 //
269
270 /**
271 * Meta-data wrapper for concrete BMH types.
272 * Each BMH type corresponds to a given sequence of basic field types (LIJFD).
273 * The fields are immutable; their values are fully specified at object construction.
274 * Each BMH type supplies an array of getter functions which may be used in lambda forms.
275 * A BMH is constructed by cloning a shorter BMH and adding one or more new field values.
276 * The shortest possible BMH has zero fields; its class is SimpleMethodHandle.
277 * BMH species are not interrelated by subtyping, even though it would appear that
278 * a shorter BMH could serve as a supertype of a longer one which extends it.
279 */
280 static class SpeciesData {
281 private final String typeChars;
282 private final BasicType[] typeCodes;
283 private final Class<? extends BoundMethodHandle> clazz;
284 // Bootstrapping requires circular relations MH -> BMH -> SpeciesData -> MH
285 // Therefore, we need a non-final link in the chain. Use array elements.
286 @Stable private final MethodHandle[] constructor;
287 @Stable private final MethodHandle[] getters;
288 @Stable private final NamedFunction[] nominalGetters;
289 @Stable private final SpeciesData[] extensions;
290
291 /*non-public*/ int fieldCount() {
292 return typeCodes.length;
293 }
294 /*non-public*/ BasicType fieldType(int i) {
295 return typeCodes[i];
296 }
297 /*non-public*/ char fieldTypeChar(int i) {
298 return typeChars.charAt(i);
299 }
300 Object fieldSignature() {
301 return typeChars;
302 }
303 public Class<? extends BoundMethodHandle> fieldHolder() {
304 return clazz;
305 }
306 public String toString() {
307 return "SpeciesData<"+fieldSignature()+">";
308 }
309
310 /**
311 * Return a {@link LambdaForm.Name} containing a {@link LambdaForm.NamedFunction} that
312 * represents a MH bound to a generic invoker, which in turn forwards to the corresponding
313 * getter.
314 */
315 NamedFunction getterFunction(int i) {
316 NamedFunction nf = nominalGetters[i];
317 assert(nf.memberDeclaringClassOrNull() == fieldHolder());
318 assert(nf.returnType() == fieldType(i));
319 return nf;
320 }
321
322 NamedFunction[] getterFunctions() {
323 return nominalGetters;
324 }
325
326 MethodHandle[] getterHandles() { return getters; }
327
328 MethodHandle constructor() {
329 return constructor[0];
330 }
331
332 static final SpeciesData EMPTY = new SpeciesData("", BoundMethodHandle.class);
333
334 private SpeciesData(String types, Class<? extends BoundMethodHandle> clazz) {
335 this.typeChars = types;
336 this.typeCodes = basicTypes(types);
337 this.clazz = clazz;
338 if (!INIT_DONE) {
339 this.constructor = new MethodHandle[1]; // only one ctor
340 this.getters = new MethodHandle[types.length()];
341 this.nominalGetters = new NamedFunction[types.length()];
342 } else {
343 this.constructor = Factory.makeCtors(clazz, types, null);
344 this.getters = Factory.makeGetters(clazz, types, null);
345 this.nominalGetters = Factory.makeNominalGetters(types, null, this.getters);
346 }
347 this.extensions = new SpeciesData[ARG_TYPE_LIMIT];
348 }
349
350 private void initForBootstrap() {
351 assert(!INIT_DONE);
352 if (constructor() == null) {
353 String types = typeChars;
354 Factory.makeCtors(clazz, types, this.constructor);
355 Factory.makeGetters(clazz, types, this.getters);
356 Factory.makeNominalGetters(types, this.nominalGetters, this.getters);
357 }
358 }
359
360 private SpeciesData(String typeChars) {
361 // Placeholder only.
362 this.typeChars = typeChars;
363 this.typeCodes = basicTypes(typeChars);
364 this.clazz = null;
365 this.constructor = null;
366 this.getters = null;
367 this.nominalGetters = null;
368 this.extensions = null;
369 }
370 private boolean isPlaceholder() { return clazz == null; }
371
372 private static final HashMap<String, SpeciesData> CACHE = new HashMap<>();
373 static { CACHE.put("", EMPTY); } // make bootstrap predictable
374 private static final boolean INIT_DONE; // set after <clinit> finishes...
375
376 SpeciesData extendWith(byte type) {
377 return extendWith(BasicType.basicType(type));
378 }
379
380 SpeciesData extendWith(BasicType type) {
381 int ord = type.ordinal();
382 SpeciesData d = extensions[ord];
383 if (d != null) return d;
384 extensions[ord] = d = get(typeChars+type.basicTypeChar());
385 return d;
386 }
387
388 private static SpeciesData get(String types) {
389 // Acquire cache lock for query.
390 SpeciesData d = lookupCache(types);
391 if (!d.isPlaceholder())
392 return d;
393 synchronized (d) {
394 // Use synch. on the placeholder to prevent multiple instantiation of one species.
395 // Creating this class forces a recursive call to getForClass.
396 if (lookupCache(types).isPlaceholder())
397 Factory.generateConcreteBMHClass(types);
398 }
399 // Reacquire cache lock.
400 d = lookupCache(types);
401 // Class loading must have upgraded the cache.
402 assert(d != null && !d.isPlaceholder());
403 return d;
404 }
405 static SpeciesData getForClass(String types, Class<? extends BoundMethodHandle> clazz) {
406 // clazz is a new class which is initializing its SPECIES_DATA field
407 return updateCache(types, new SpeciesData(types, clazz));
408 }
409 private static synchronized SpeciesData lookupCache(String types) {
410 SpeciesData d = CACHE.get(types);
411 if (d != null) return d;
412 d = new SpeciesData(types);
413 assert(d.isPlaceholder());
414 CACHE.put(types, d);
415 return d;
416 }
417 private static synchronized SpeciesData updateCache(String types, SpeciesData d) {
418 SpeciesData d2;
419 assert((d2 = CACHE.get(types)) == null || d2.isPlaceholder());
420 assert(!d.isPlaceholder());
421 CACHE.put(types, d);
422 return d;
423 }
424
425 static {
426 // pre-fill the BMH speciesdata cache with BMH's inner classes
427 final Class<BoundMethodHandle> rootCls = BoundMethodHandle.class;
428 try {
429 for (Class<?> c : rootCls.getDeclaredClasses()) {
430 if (rootCls.isAssignableFrom(c)) {
431 final Class<? extends BoundMethodHandle> cbmh = c.asSubclass(BoundMethodHandle.class);
432 SpeciesData d = Factory.speciesDataFromConcreteBMHClass(cbmh);
433 assert(d != null) : cbmh.getName();
434 assert(d.clazz == cbmh);
435 assert(d == lookupCache(d.typeChars));
436 }
437 }
438 } catch (Throwable e) {
439 throw newInternalError(e);
440 }
441
442 for (SpeciesData d : CACHE.values()) {
443 d.initForBootstrap();
444 }
445 // Note: Do not simplify this, because INIT_DONE must not be
446 // a compile-time constant during bootstrapping.
447 INIT_DONE = Boolean.TRUE;
448 }
449 }
450
451 static SpeciesData getSpeciesData(String types) {
452 return SpeciesData.get(types);
453 }
454
455 /**
456 * Generation of concrete BMH classes.
457 *
458 * A concrete BMH species is fit for binding a number of values adhering to a
459 * given type pattern. Reference types are erased.
460 *
461 * BMH species are cached by type pattern.
462 *
463 * A BMH species has a number of fields with the concrete (possibly erased) types of
464 * bound values. Setters are provided as an API in BMH. Getters are exposed as MHs,
465 * which can be included as names in lambda forms.
466 */
467 static class Factory {
468
469 static final String JLO_SIG = "Ljava/lang/Object;";
470 static final String JLS_SIG = "Ljava/lang/String;";
471 static final String JLC_SIG = "Ljava/lang/Class;";
472 static final String MH = "java/lang/invoke/MethodHandle";
473 static final String MH_SIG = "L"+MH+";";
474 static final String BMH = "java/lang/invoke/BoundMethodHandle";
475 static final String BMH_SIG = "L"+BMH+";";
476 static final String SPECIES_DATA = "java/lang/invoke/BoundMethodHandle$SpeciesData";
477 static final String SPECIES_DATA_SIG = "L"+SPECIES_DATA+";";
478
479 static final String SPECIES_PREFIX_NAME = "Species_";
480 static final String SPECIES_PREFIX_PATH = BMH + "$" + SPECIES_PREFIX_NAME;
481
482 static final String BMHSPECIES_DATA_EWI_SIG = "(B)" + SPECIES_DATA_SIG;
483 static final String BMHSPECIES_DATA_GFC_SIG = "(" + JLS_SIG + JLC_SIG + ")" + SPECIES_DATA_SIG;
484 static final String MYSPECIES_DATA_SIG = "()" + SPECIES_DATA_SIG;
485 static final String VOID_SIG = "()V";
486 static final String INT_SIG = "()I";
487
488 static final String SIG_INCIPIT = "(Ljava/lang/invoke/MethodType;Ljava/lang/invoke/LambdaForm;";
489
490 static final String[] E_THROWABLE = new String[] { "java/lang/Throwable" };
491
492 /**
493 * Generate a concrete subclass of BMH for a given combination of bound types.
494 *
495 * A concrete BMH species adheres to the following schema:
496 *
497 * <pre>
498 * class Species_[[types]] extends BoundMethodHandle {
499 * [[fields]]
500 * final SpeciesData speciesData() { return SpeciesData.get("[[types]]"); }
501 * }
502 * </pre>
503 *
504 * The {@code [[types]]} signature is precisely the string that is passed to this
505 * method.
506 *
507 * The {@code [[fields]]} section consists of one field definition per character in
508 * the type signature, adhering to the naming schema described in the definition of
509 * {@link #makeFieldName}.
510 *
511 * For example, a concrete BMH species for two reference and one integral bound values
512 * would have the following shape:
513 *
514 * <pre>
515 * class BoundMethodHandle { ... private static
516 * final class Species_LLI extends BoundMethodHandle {
517 * final Object argL0;
518 * final Object argL1;
519 * final int argI2;
520 * private Species_LLI(MethodType mt, LambdaForm lf, Object argL0, Object argL1, int argI2) {
521 * super(mt, lf);
522 * this.argL0 = argL0;
523 * this.argL1 = argL1;
524 * this.argI2 = argI2;
525 * }
526 * final SpeciesData speciesData() { return SPECIES_DATA; }
527 * final int fieldCount() { return 3; }
528 * static final SpeciesData SPECIES_DATA = SpeciesData.getForClass("LLI", Species_LLI.class);
529 * static BoundMethodHandle make(MethodType mt, LambdaForm lf, Object argL0, Object argL1, int argI2) {
530 * return new Species_LLI(mt, lf, argL0, argL1, argI2);
531 * }
532 * final BoundMethodHandle copyWith(MethodType mt, LambdaForm lf) {
533 * return new Species_LLI(mt, lf, argL0, argL1, argI2);
534 * }
535 * final BoundMethodHandle copyWithExtendL(MethodType mt, LambdaForm lf, Object narg) {
536 * return SPECIES_DATA.extendWith(L_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);
537 * }
538 * final BoundMethodHandle copyWithExtendI(MethodType mt, LambdaForm lf, int narg) {
539 * return SPECIES_DATA.extendWith(I_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);
540 * }
541 * final BoundMethodHandle copyWithExtendJ(MethodType mt, LambdaForm lf, long narg) {
542 * return SPECIES_DATA.extendWith(J_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);
543 * }
544 * final BoundMethodHandle copyWithExtendF(MethodType mt, LambdaForm lf, float narg) {
545 * return SPECIES_DATA.extendWith(F_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);
546 * }
547 * public final BoundMethodHandle copyWithExtendD(MethodType mt, LambdaForm lf, double narg) {
548 * return SPECIES_DATA.extendWith(D_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);
549 * }
550 * }
551 * </pre>
552 *
553 * @param types the type signature, wherein reference types are erased to 'L'
554 * @return the generated concrete BMH class
555 */
556 static Class<? extends BoundMethodHandle> generateConcreteBMHClass(String types) {
557 final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS + ClassWriter.COMPUTE_FRAMES);
558
559 String shortTypes = LambdaForm.shortenSignature(types);
560 final String className = SPECIES_PREFIX_PATH + shortTypes;
561 final String sourceFile = SPECIES_PREFIX_NAME + shortTypes;
562 final int NOT_ACC_PUBLIC = 0; // not ACC_PUBLIC
563 cw.visit(V1_6, NOT_ACC_PUBLIC + ACC_FINAL + ACC_SUPER, className, null, BMH, null);
564 cw.visitSource(sourceFile, null);
565
566 // emit static types and SPECIES_DATA fields
567 cw.visitField(NOT_ACC_PUBLIC + ACC_STATIC, "SPECIES_DATA", SPECIES_DATA_SIG, null, null).visitEnd();
568
569 // emit bound argument fields
570 for (int i = 0; i < types.length(); ++i) {
571 final char t = types.charAt(i);
572 final String fieldName = makeFieldName(types, i);
573 final String fieldDesc = t == 'L' ? JLO_SIG : String.valueOf(t);
574 cw.visitField(ACC_FINAL, fieldName, fieldDesc, null, null).visitEnd();
575 }
576
577 MethodVisitor mv;
578
579 // emit constructor
580 mv = cw.visitMethod(ACC_PRIVATE, "<init>", makeSignature(types, true), null, null);
581 mv.visitCode();
582 mv.visitVarInsn(ALOAD, 0); // this
583 mv.visitVarInsn(ALOAD, 1); // type
584 mv.visitVarInsn(ALOAD, 2); // form
585
586 mv.visitMethodInsn(INVOKESPECIAL, BMH, "<init>", makeSignature("", true), false);
587
588 for (int i = 0, j = 0; i < types.length(); ++i, ++j) {
589 // i counts the arguments, j counts corresponding argument slots
590 char t = types.charAt(i);
591 mv.visitVarInsn(ALOAD, 0);
592 mv.visitVarInsn(typeLoadOp(t), j + 3); // parameters start at 3
593 mv.visitFieldInsn(PUTFIELD, className, makeFieldName(types, i), typeSig(t));
594 if (t == 'J' || t == 'D') {
595 ++j; // adjust argument register access
596 }
597 }
598
599 mv.visitInsn(RETURN);
600 mv.visitMaxs(0, 0);
601 mv.visitEnd();
602
603 // emit implementation of speciesData()
604 mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "speciesData", MYSPECIES_DATA_SIG, null, null);
605 mv.visitCode();
606 mv.visitFieldInsn(GETSTATIC, className, "SPECIES_DATA", SPECIES_DATA_SIG);
607 mv.visitInsn(ARETURN);
608 mv.visitMaxs(0, 0);
609 mv.visitEnd();
610
611 // emit implementation of fieldCount()
612 mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "fieldCount", INT_SIG, null, null);
613 mv.visitCode();
614 int fc = types.length();
615 if (fc <= (ICONST_5 - ICONST_0)) {
616 mv.visitInsn(ICONST_0 + fc);
617 } else {
618 mv.visitIntInsn(SIPUSH, fc);
619 }
620 mv.visitInsn(IRETURN);
621 mv.visitMaxs(0, 0);
622 mv.visitEnd();
623 // emit make() ...factory method wrapping constructor
624 mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_STATIC, "make", makeSignature(types, false), null, null);
625 mv.visitCode();
626 // make instance
627 mv.visitTypeInsn(NEW, className);
628 mv.visitInsn(DUP);
629 // load mt, lf
630 mv.visitVarInsn(ALOAD, 0); // type
631 mv.visitVarInsn(ALOAD, 1); // form
632 // load factory method arguments
633 for (int i = 0, j = 0; i < types.length(); ++i, ++j) {
634 // i counts the arguments, j counts corresponding argument slots
635 char t = types.charAt(i);
636 mv.visitVarInsn(typeLoadOp(t), j + 2); // parameters start at 3
637 if (t == 'J' || t == 'D') {
638 ++j; // adjust argument register access
639 }
640 }
641
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 // emit copyWith()
649 mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "copyWith", makeSignature("", false), null, null);
650 mv.visitCode();
651 // make instance
652 mv.visitTypeInsn(NEW, className);
653 mv.visitInsn(DUP);
654 // load mt, lf
655 mv.visitVarInsn(ALOAD, 1);
656 mv.visitVarInsn(ALOAD, 2);
657 // put fields on the stack
658 emitPushFields(types, className, mv);
659 // finally, invoke the constructor and return
660 mv.visitMethodInsn(INVOKESPECIAL, className, "<init>", makeSignature(types, true), false);
661 mv.visitInsn(ARETURN);
662 mv.visitMaxs(0, 0);
663 mv.visitEnd();
664
665 // for each type, emit copyWithExtendT()
666 for (BasicType type : BasicType.ARG_TYPES) {
667 int ord = type.ordinal();
668 char btChar = type.basicTypeChar();
669 mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "copyWithExtend" + btChar, makeSignature(String.valueOf(btChar), false), null, E_THROWABLE);
670 mv.visitCode();
671 // return SPECIES_DATA.extendWith(t).constructor().invokeBasic(mt, lf, argL0, ..., narg)
672 // obtain constructor
673 mv.visitFieldInsn(GETSTATIC, className, "SPECIES_DATA", SPECIES_DATA_SIG);
674 int iconstInsn = ICONST_0 + ord;
675 assert(iconstInsn <= ICONST_5);
676 mv.visitInsn(iconstInsn);
677 mv.visitMethodInsn(INVOKEVIRTUAL, SPECIES_DATA, "extendWith", BMHSPECIES_DATA_EWI_SIG, false);
678 mv.visitMethodInsn(INVOKEVIRTUAL, SPECIES_DATA, "constructor", "()" + MH_SIG, false);
679 // load mt, lf
680 mv.visitVarInsn(ALOAD, 1);
681 mv.visitVarInsn(ALOAD, 2);
682 // put fields on the stack
683 emitPushFields(types, className, mv);
684 // put narg on stack
685 mv.visitVarInsn(typeLoadOp(btChar), 3);
686 // finally, invoke the constructor and return
687 mv.visitMethodInsn(INVOKEVIRTUAL, MH, "invokeBasic", makeSignature(types + btChar, false), false);
688 mv.visitInsn(ARETURN);
689 mv.visitMaxs(0, 0);
690 mv.visitEnd();
691 }
692
693 // emit class initializer
694 mv = cw.visitMethod(NOT_ACC_PUBLIC | ACC_STATIC, "<clinit>", VOID_SIG, null, null);
695 mv.visitCode();
696 mv.visitLdcInsn(types);
697 mv.visitLdcInsn(Type.getObjectType(className));
698 mv.visitMethodInsn(INVOKESTATIC, SPECIES_DATA, "getForClass", BMHSPECIES_DATA_GFC_SIG, false);
699 mv.visitFieldInsn(PUTSTATIC, className, "SPECIES_DATA", SPECIES_DATA_SIG);
700 mv.visitInsn(RETURN);
701 mv.visitMaxs(0, 0);
702 mv.visitEnd();
703
704 cw.visitEnd();
705
706 // load class
707 final byte[] classFile = cw.toByteArray();
708 InvokerBytecodeGenerator.maybeDump(className, classFile);
709 Class<? extends BoundMethodHandle> bmhClass =
710 //UNSAFE.defineAnonymousClass(BoundMethodHandle.class, classFile, null).asSubclass(BoundMethodHandle.class);
711 UNSAFE.defineClass(className, classFile, 0, classFile.length,
712 BoundMethodHandle.class.getClassLoader(), null)
713 .asSubclass(BoundMethodHandle.class);
714 UNSAFE.ensureClassInitialized(bmhClass);
715
716 return bmhClass;
717 }
718
719 private static int typeLoadOp(char t) {
720 switch (t) {
721 case 'L': return ALOAD;
722 case 'I': return ILOAD;
723 case 'J': return LLOAD;
724 case 'F': return FLOAD;
725 case 'D': return DLOAD;
726 default : throw newInternalError("unrecognized type " + t);
727 }
728 }
729
730 private static void emitPushFields(String types, String className, MethodVisitor mv) {
731 for (int i = 0; i < types.length(); ++i) {
732 char tc = types.charAt(i);
733 mv.visitVarInsn(ALOAD, 0);
734 mv.visitFieldInsn(GETFIELD, className, makeFieldName(types, i), typeSig(tc));
735 }
736 }
737
738 static String typeSig(char t) {
739 return t == 'L' ? JLO_SIG : String.valueOf(t);
740 }
741
742 //
743 // Getter MH generation.
744 //
745
746 private static MethodHandle makeGetter(Class<?> cbmhClass, String types, int index) {
747 String fieldName = makeFieldName(types, index);
748 Class<?> fieldType = Wrapper.forBasicType(types.charAt(index)).primitiveType();
749 try {
750 return LOOKUP.findGetter(cbmhClass, fieldName, fieldType);
751 } catch (NoSuchFieldException | IllegalAccessException e) {
752 throw newInternalError(e);
753 }
754 }
755
756 static MethodHandle[] makeGetters(Class<?> cbmhClass, String types, MethodHandle[] mhs) {
757 if (mhs == null) mhs = new MethodHandle[types.length()];
758 for (int i = 0; i < mhs.length; ++i) {
759 mhs[i] = makeGetter(cbmhClass, types, i);
760 assert(mhs[i].internalMemberName().getDeclaringClass() == cbmhClass);
761 }
762 return mhs;
763 }
764
765 static MethodHandle[] makeCtors(Class<? extends BoundMethodHandle> cbmh, String types, MethodHandle mhs[]) {
766 if (mhs == null) mhs = new MethodHandle[1];
767 if (types.equals("")) return mhs; // hack for empty BMH species
768 mhs[0] = makeCbmhCtor(cbmh, types);
769 return mhs;
770 }
771
772 static NamedFunction[] makeNominalGetters(String types, NamedFunction[] nfs, MethodHandle[] getters) {
773 if (nfs == null) nfs = new NamedFunction[types.length()];
774 for (int i = 0; i < nfs.length; ++i) {
775 nfs[i] = new NamedFunction(getters[i]);
776 }
777 return nfs;
778 }
779
780 //
781 // Auxiliary methods.
782 //
783
784 static SpeciesData speciesDataFromConcreteBMHClass(Class<? extends BoundMethodHandle> cbmh) {
785 try {
786 Field F_SPECIES_DATA = cbmh.getDeclaredField("SPECIES_DATA");
787 return (SpeciesData) F_SPECIES_DATA.get(null);
788 } catch (ReflectiveOperationException ex) {
789 throw newInternalError(ex);
790 }
791 }
792
793 /**
794 * Field names in concrete BMHs adhere to this pattern:
795 * arg + type + index
796 * where type is a single character (L, I, J, F, D).
797 */
798 private static String makeFieldName(String types, int index) {
799 assert index >= 0 && index < types.length();
800 return "arg" + types.charAt(index) + index;
801 }
802
803 private static String makeSignature(String types, boolean ctor) {
804 StringBuilder buf = new StringBuilder(SIG_INCIPIT);
805 for (char c : types.toCharArray()) {
806 buf.append(typeSig(c));
807 }
808 return buf.append(')').append(ctor ? "V" : BMH_SIG).toString();
809 }
810
811 static MethodHandle makeCbmhCtor(Class<? extends BoundMethodHandle> cbmh, String types) {
812 try {
813 return LOOKUP.findStatic(cbmh, "make", MethodType.fromMethodDescriptorString(makeSignature(types, false), null));
814 } catch (NoSuchMethodException | IllegalAccessException | IllegalArgumentException | TypeNotPresentException e) {
815 throw newInternalError(e);
816 }
817 }
818 }
819
820 private static final Lookup LOOKUP = Lookup.IMPL_LOOKUP;
821
822 /**
823 * All subclasses must provide such a value describing their type signature.
824 */
825 static final SpeciesData SPECIES_DATA = SpeciesData.EMPTY;
826
827 private static final SpeciesData[] SPECIES_DATA_CACHE = new SpeciesData[5];
828 private static SpeciesData checkCache(int size, String types) {
829 int idx = size - 1;
830 SpeciesData data = SPECIES_DATA_CACHE[idx];
831 if (data != null) return data;
832 SPECIES_DATA_CACHE[idx] = data = getSpeciesData(types);
833 return data;
834 }
835 static SpeciesData speciesData_L() { return checkCache(1, "L"); }
836 static SpeciesData speciesData_LL() { return checkCache(2, "LL"); }
837 static SpeciesData speciesData_LLL() { return checkCache(3, "LLL"); }
838 static SpeciesData speciesData_LLLL() { return checkCache(4, "LLLL"); }
839 static SpeciesData speciesData_LLLLL() { return checkCache(5, "LLLLL"); }
840 }