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.MethodHandleStatics.*; 31 32 import java.lang.invoke.LambdaForm.NamedFunction; 33 import java.lang.invoke.MethodHandles.Lookup; 34 import java.lang.reflect.Field; 35 import java.util.Arrays; 36 import java.util.HashMap; 37 38 import sun.invoke.util.ValueConversions; 39 import sun.invoke.util.Wrapper; 40 41 import jdk.internal.org.objectweb.asm.ClassWriter; 42 import jdk.internal.org.objectweb.asm.MethodVisitor; 43 import jdk.internal.org.objectweb.asm.Type; 44 45 /** 46 * The flavor of method handle which emulates an invoke instruction 47 * on a predetermined argument. The JVM dispatches to the correct method 48 * when the handle is created, not when it is invoked. 49 * 50 * All bound arguments are encapsulated in dedicated species. 51 */ 52 /* non-public */ abstract class BoundMethodHandle extends MethodHandle { 53 54 /* non-public */ BoundMethodHandle(MethodType type, LambdaForm form) { 55 super(type, form); 56 } 57 58 // 59 // BMH API and internals 60 // 61 62 static MethodHandle bindSingle(MethodType type, LambdaForm form, byte xtype, Object x) { 63 // for some type signatures, there exist pre-defined concrete BMH classes 64 try { 65 switch (xtype) { 66 case L_TYPE: 67 if (true) return bindSingle(type, form, x); // Use known fast path. 68 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(L_TYPE).constructor[0].invokeBasic(type, form, x); 69 case I_TYPE: 70 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(I_TYPE).constructor[0].invokeBasic(type, form, ValueConversions.widenSubword(x)); 71 case J_TYPE: 72 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(J_TYPE).constructor[0].invokeBasic(type, form, (long) x); 73 case F_TYPE: 74 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(F_TYPE).constructor[0].invokeBasic(type, form, (float) x); 75 case D_TYPE: 76 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(D_TYPE).constructor[0].invokeBasic(type, form, (double) x); 77 default : throw new InternalError("unexpected xtype: " + xtype); 78 } 79 } catch (Throwable t) { 80 throw newInternalError(t); 81 } 82 } 83 84 static MethodHandle bindSingle(MethodType type, LambdaForm form, Object x) { 85 return new Species_L(type, form, x); 86 } 87 88 MethodHandle cloneExtend(MethodType type, LambdaForm form, byte xtype, Object x) { 89 try { 90 switch (xtype) { 91 case L_TYPE: return copyWithExtendL(type, form, x); 92 case I_TYPE: return copyWithExtendI(type, form, ValueConversions.widenSubword(x)); 93 case J_TYPE: return copyWithExtendJ(type, form, (long) x); 94 case F_TYPE: return copyWithExtendF(type, form, (float) x); 95 case D_TYPE: return copyWithExtendD(type, form, (double) x); 96 } 97 } catch (Throwable t) { 98 throw newInternalError(t); 99 } 100 throw new InternalError("unexpected type: " + xtype); 101 } 102 103 @Override 104 MethodHandle bindArgument(int pos, byte basicType, Object value) { 105 MethodType type = type().dropParameterTypes(pos, pos+1); 106 LambdaForm form = internalForm().bind(1+pos, speciesData()); 107 return cloneExtend(type, form, basicType, value); 108 } 109 110 @Override 111 MethodHandle dropArguments(MethodType srcType, int pos, int drops) { 112 LambdaForm form = internalForm().addArguments(pos, srcType.parameterList().subList(pos, pos + drops)); 113 try { 114 return copyWith(srcType, form); 115 } catch (Throwable t) { 116 throw newInternalError(t); 117 } 118 } 119 120 @Override 121 MethodHandle permuteArguments(MethodType newType, int[] reorder) { 122 try { 123 return copyWith(newType, form.permuteArguments(1, reorder, basicTypes(newType.parameterList()))); 124 } catch (Throwable t) { 125 throw newInternalError(t); 126 } 127 } 128 129 static final String EXTENSION_TYPES = "LIJFD"; 130 static final byte INDEX_L = 0, INDEX_I = 1, INDEX_J = 2, INDEX_F = 3, INDEX_D = 4; 131 static byte extensionIndex(char type) { 132 int i = EXTENSION_TYPES.indexOf(type); 133 if (i < 0) throw new InternalError(); 134 return (byte) i; 135 } 136 137 /** 138 * Return the {@link SpeciesData} instance representing this BMH species. All subclasses must provide a 139 * static field containing this value, and they must accordingly implement this method. 140 */ 141 public abstract SpeciesData speciesData(); 142 143 /** 144 * Return the number of fields in this BMH. Equivalent to speciesData().fieldCount(). 145 */ 146 public abstract int fieldCount(); 147 148 @Override 149 final Object internalProperties() { 150 return "/BMH="+internalValues(); 151 } 152 153 @Override 154 final Object internalValues() { 155 Object[] boundValues = new Object[speciesData().fieldCount()]; 156 for (int i = 0; i < boundValues.length; ++i) { 157 boundValues[i] = arg(i); 158 } 159 return Arrays.asList(boundValues); 160 } 161 162 public final Object arg(int i) { 163 try { 164 switch (speciesData().fieldType(i)) { 165 case L_TYPE: return speciesData().getters[i].invokeBasic(this); 166 case I_TYPE: return (int) speciesData().getters[i].invokeBasic(this); 167 case J_TYPE: return (long) speciesData().getters[i].invokeBasic(this); 168 case F_TYPE: return (float) speciesData().getters[i].invokeBasic(this); 169 case D_TYPE: return (double) speciesData().getters[i].invokeBasic(this); 170 } 171 } catch (Throwable ex) { 172 throw newInternalError(ex); 173 } 174 throw new InternalError("unexpected type: " + speciesData().typeChars+"."+i); 175 } 176 177 // 178 // cloning API 179 // 180 181 // The following is a grossly irregular hack: 182 @Override MethodHandle reinvokerTarget() { 183 try { 184 return (MethodHandle) arg(0); 185 } catch (Throwable ex) { 186 throw newInternalError(ex); 187 } 188 } 189 190 @Override 191 public abstract BoundMethodHandle copyWith(MethodType mt, LambdaForm lf); 192 public abstract BoundMethodHandle copyWithExtendL(MethodType mt, LambdaForm lf, Object narg); 193 public abstract BoundMethodHandle copyWithExtendI(MethodType mt, LambdaForm lf, int narg); 194 public abstract BoundMethodHandle copyWithExtendJ(MethodType mt, LambdaForm lf, long narg); 195 public abstract BoundMethodHandle copyWithExtendF(MethodType mt, LambdaForm lf, float narg); 196 public abstract BoundMethodHandle copyWithExtendD(MethodType mt, LambdaForm lf, double narg); 197 198 // 199 // concrete BMH classes required to close bootstrap loops 200 // 201 202 private // make it private to force users to access the enclosing class first 203 static final class Species_L extends BoundMethodHandle { 204 final Object argL0; 205 private Species_L(MethodType mt, LambdaForm lf, Object argL0) { 206 super(mt, lf); 207 this.argL0 = argL0; 208 } 209 @Override 210 public SpeciesData speciesData() { 211 return SPECIES_DATA; 212 } 213 @Override 214 public int fieldCount() { 215 return 1; 216 } 217 public static final SpeciesData SPECIES_DATA = SpeciesData.getForClass("L", Species_L.class); 218 public static BoundMethodHandle make(MethodType mt, LambdaForm lf, Object argL0) { 219 return new Species_L(mt, lf, argL0); 220 } 221 @Override 222 public final BoundMethodHandle copyWith(MethodType mt, LambdaForm lf) { 223 return new Species_L(mt, lf, argL0); 224 } 225 @Override 226 public final BoundMethodHandle copyWithExtendL(MethodType mt, LambdaForm lf, Object narg) { 227 try { 228 return (BoundMethodHandle) SPECIES_DATA.extendWith(L_TYPE).constructor[0].invokeBasic(mt, lf, argL0, narg); 229 } catch (Throwable ex) { 230 throw uncaughtException(ex); 231 } 232 } 233 @Override 234 public final BoundMethodHandle copyWithExtendI(MethodType mt, LambdaForm lf, int narg) { 235 try { 236 return (BoundMethodHandle) SPECIES_DATA.extendWith(I_TYPE).constructor[0].invokeBasic(mt, lf, argL0, narg); 237 } catch (Throwable ex) { 238 throw uncaughtException(ex); 239 } 240 } 241 @Override 242 public final BoundMethodHandle copyWithExtendJ(MethodType mt, LambdaForm lf, long narg) { 243 try { 244 return (BoundMethodHandle) SPECIES_DATA.extendWith(J_TYPE).constructor[0].invokeBasic(mt, lf, argL0, narg); 245 } catch (Throwable ex) { 246 throw uncaughtException(ex); 247 } 248 } 249 @Override 250 public final BoundMethodHandle copyWithExtendF(MethodType mt, LambdaForm lf, float narg) { 251 try { 252 return (BoundMethodHandle) SPECIES_DATA.extendWith(F_TYPE).constructor[0].invokeBasic(mt, lf, argL0, narg); 253 } catch (Throwable ex) { 254 throw uncaughtException(ex); 255 } 256 } 257 @Override 258 public final BoundMethodHandle copyWithExtendD(MethodType mt, LambdaForm lf, double narg) { 259 try { 260 return (BoundMethodHandle) SPECIES_DATA.extendWith(D_TYPE).constructor[0].invokeBasic(mt, lf, argL0, narg); 261 } catch (Throwable ex) { 262 throw uncaughtException(ex); 263 } 264 } 265 } 266 267 // 268 // BMH species meta-data 269 // 270 271 /** 272 * Meta-data wrapper for concrete BMH types. 273 * Each BMH type corresponds to a given sequence of basic field types (LIJFD). 274 * The fields are immutable; their values are fully specified at object construction. 275 * Each BMH type supplies an array of getter functions which may be used in lambda forms. 276 * A BMH is constructed by cloning a shorter BMH and adding one or more new field values. 277 * As a degenerate and common case, the "shorter BMH" can be missing, and contributes zero prior fields. 278 */ 279 static class SpeciesData { 280 final String typeChars; 281 final byte[] typeCodes; 282 final Class<? extends BoundMethodHandle> clazz; 283 // Bootstrapping requires circular relations MH -> BMH -> SpeciesData -> MH 284 // Therefore, we need a non-final link in the chain. Use array elements. 285 final MethodHandle[] constructor; 286 final MethodHandle[] getters; 287 final NamedFunction[] nominalGetters; 288 final SpeciesData[] extensions; 289 290 public int fieldCount() { 291 return typeCodes.length; 292 } 293 public byte fieldType(int i) { 294 return typeCodes[i]; 295 } 296 public char fieldTypeChar(int i) { 297 return typeChars.charAt(i); 298 } 299 300 public String toString() { 301 return "SpeciesData["+(isPlaceholder() ? "<placeholder>" : clazz.getSimpleName())+":"+typeChars+"]"; 302 } 303 304 /** 305 * Return a {@link LambdaForm.Name} containing a {@link LambdaForm.NamedFunction} that 306 * represents a MH bound to a generic invoker, which in turn forwards to the corresponding 307 * getter. 308 */ 309 NamedFunction getterFunction(int i) { 310 return nominalGetters[i]; 311 } 312 313 static final SpeciesData EMPTY = new SpeciesData("", BoundMethodHandle.class); 314 315 private SpeciesData(String types, Class<? extends BoundMethodHandle> clazz) { 316 this.typeChars = types; 317 this.typeCodes = basicTypes(types); 318 this.clazz = clazz; 319 if (!INIT_DONE) { 320 this.constructor = new MethodHandle[1]; // only one ctor 321 this.getters = new MethodHandle[types.length()]; 322 this.nominalGetters = new NamedFunction[types.length()]; 323 } else { 324 this.constructor = Factory.makeCtors(clazz, types, null); 325 this.getters = Factory.makeGetters(clazz, types, null); 326 this.nominalGetters = Factory.makeNominalGetters(clazz, types, null, this.getters); 327 } 328 this.extensions = new SpeciesData[ARG_TYPE_LIMIT]; 329 } 330 331 private void initForBootstrap() { 332 assert(!INIT_DONE); 333 if (constructor[0] == null) { 334 String types = typeChars; 335 Factory.makeCtors(clazz, types, this.constructor); 336 Factory.makeGetters(clazz, types, this.getters); 337 Factory.makeNominalGetters(clazz, types, this.nominalGetters, this.getters); 338 } 339 } 340 341 private SpeciesData(String typeChars) { 342 // Placeholder only. 343 this.typeChars = typeChars; 344 this.typeCodes = basicTypes(typeChars); 345 this.clazz = null; 346 this.constructor = null; 347 this.getters = null; 348 this.nominalGetters = null; 349 this.extensions = null; 350 } 351 private boolean isPlaceholder() { return clazz == null; } 352 353 private static final HashMap<String, SpeciesData> CACHE = new HashMap<>(); 354 static { CACHE.put("", EMPTY); } // make bootstrap predictable 355 private static final boolean INIT_DONE; // set after <clinit> finishes... 356 357 SpeciesData extendWith(byte type) { 358 SpeciesData d = extensions[type]; 359 if (d != null) return d; 360 extensions[type] = d = get(typeChars+basicTypeChar(type)); 361 return d; 362 } 363 364 SpeciesData extendWith(Class<?> type) { 365 return extendWith(basicType(type)); 366 } 367 368 SpeciesData extendWithChar(char type) { 369 return extendWith(basicType(type)); 370 } 371 372 private static SpeciesData get(String types) { 373 // Acquire cache lock for query. 374 SpeciesData d = lookupCache(types); 375 if (!d.isPlaceholder()) 376 return d; 377 synchronized (d) { 378 // Use synch. on the placeholder to prevent multiple instantiation of one species. 379 // Creating this class forces a recursive call to getForClass. 380 if (lookupCache(types).isPlaceholder()) 381 Factory.generateConcreteBMHClass(types); 382 } 383 // Reacquire cache lock. 384 d = lookupCache(types); 385 // Class loading must have upgraded the cache. 386 assert(d != null && !d.isPlaceholder()); 387 return d; 388 } 389 static SpeciesData getForClass(String types, Class<? extends BoundMethodHandle> clazz) { 390 // clazz is a new class which is initializing its SPECIES_DATA field 391 return updateCache(types, new SpeciesData(types, clazz)); 392 } 393 private static synchronized SpeciesData lookupCache(String types) { 394 SpeciesData d = CACHE.get(types); 395 if (d != null) return d; 396 d = new SpeciesData(types); 397 assert(d.isPlaceholder()); 398 CACHE.put(types, d); 399 return d; 400 } 401 private static synchronized SpeciesData updateCache(String types, SpeciesData d) { 402 SpeciesData d2; 403 assert((d2 = CACHE.get(types)) == null || d2.isPlaceholder()); 404 assert(!d.isPlaceholder()); 405 CACHE.put(types, d); 406 return d; 407 } 408 409 static void initStatics() {} 410 411 static { 412 // pre-fill the BMH speciesdata cache with BMH's inner classes 413 final Class<BoundMethodHandle> rootCls = BoundMethodHandle.class; 414 try { 415 for (Class<?> c : rootCls.getDeclaredClasses()) { 416 if (rootCls.isAssignableFrom(c)) { 417 final Class<? extends BoundMethodHandle> cbmh = c.asSubclass(BoundMethodHandle.class); 418 SpeciesData d = Factory.speciesDataFromConcreteBMHClass(cbmh); 419 assert(d != null) : cbmh.getName(); 420 assert(d.clazz == cbmh); 421 assert(d == lookupCache(d.typeChars)); 422 } 423 } 424 } catch (Throwable e) { 425 throw newInternalError(e); 426 } 427 428 for (SpeciesData d : CACHE.values()) { 429 d.initForBootstrap(); 430 } 431 // Note: Do not simplify this, because INIT_DONE must not be 432 // a compile-time constant during bootstrapping. 433 INIT_DONE = Boolean.TRUE; 434 } 435 } 436 437 static SpeciesData getSpeciesData(String types) { 438 return SpeciesData.get(types); 439 } 440 441 /** 442 * Generation of concrete BMH classes. 443 * 444 * A concrete BMH species is fit for binding a number of values adhering to a 445 * given type pattern. Reference types are erased. 446 * 447 * BMH species are cached by type pattern. 448 * 449 * A BMH species has a number of fields with the concrete (possibly erased) types of 450 * bound values. Setters are provided as an API in BMH. Getters are exposed as MHs, 451 * which can be included as names in lambda forms. 452 */ 453 static class Factory { 454 455 static final String JLO_SIG = "Ljava/lang/Object;"; 456 static final String JLS_SIG = "Ljava/lang/String;"; 457 static final String JLC_SIG = "Ljava/lang/Class;"; 458 static final String MH = "java/lang/invoke/MethodHandle"; 459 static final String MH_SIG = "L"+MH+";"; 460 static final String BMH = "java/lang/invoke/BoundMethodHandle"; 461 static final String BMH_SIG = "L"+BMH+";"; 462 static final String SPECIES_DATA = "java/lang/invoke/BoundMethodHandle$SpeciesData"; 463 static final String SPECIES_DATA_SIG = "L"+SPECIES_DATA+";"; 464 465 static final String SPECIES_PREFIX_NAME = "Species_"; 466 static final String SPECIES_PREFIX_PATH = BMH + "$" + SPECIES_PREFIX_NAME; 467 468 static final String BMHSPECIES_DATA_EWI_SIG = "(B)" + SPECIES_DATA_SIG; 469 static final String BMHSPECIES_DATA_GFC_SIG = "(" + JLS_SIG + JLC_SIG + ")" + SPECIES_DATA_SIG; 470 static final String MYSPECIES_DATA_SIG = "()" + SPECIES_DATA_SIG; 471 static final String VOID_SIG = "()V"; 472 static final String INT_SIG = "()I"; 473 474 static final String SIG_INCIPIT = "(Ljava/lang/invoke/MethodType;Ljava/lang/invoke/LambdaForm;"; 475 476 static final String[] E_THROWABLE = new String[] { "java/lang/Throwable" }; 477 478 /** 479 * Generate a concrete subclass of BMH for a given combination of bound types. 480 * 481 * A concrete BMH species adheres to the following schema: 482 * 483 * <pre> 484 * class Species_[[types]] extends BoundMethodHandle { 485 * [[fields]] 486 * final SpeciesData speciesData() { return SpeciesData.get("[[types]]"); } 487 * } 488 * </pre> 489 * 490 * The {@code [[types]]} signature is precisely the string that is passed to this 491 * method. 492 * 493 * The {@code [[fields]]} section consists of one field definition per character in 494 * the type signature, adhering to the naming schema described in the definition of 495 * {@link #makeFieldName}. 496 * 497 * For example, a concrete BMH species for two reference and one integral bound values 498 * would have the following shape: 499 * 500 * <pre> 501 * class BoundMethodHandle { ... private static 502 * final class Species_LLI extends BoundMethodHandle { 503 * final Object argL0; 504 * final Object argL1; 505 * final int argI2; 506 * private Species_LLI(MethodType mt, LambdaForm lf, Object argL0, Object argL1, int argI2) { 507 * super(mt, lf); 508 * this.argL0 = argL0; 509 * this.argL1 = argL1; 510 * this.argI2 = argI2; 511 * } 512 * public final SpeciesData speciesData() { return SPECIES_DATA; } 513 * public final int fieldCount() { return 3; } 514 * public static final SpeciesData SPECIES_DATA = SpeciesData.getForClass("LLI", Species_LLI.class); 515 * public BoundMethodHandle make(MethodType mt, LambdaForm lf, Object argL0, Object argL1, int argI2) { 516 * return new Species_LLI(mt, lf, argL0, argL1, argI2); 517 * } 518 * public final BoundMethodHandle copyWith(MethodType mt, LambdaForm lf) { 519 * return new Species_LLI(mt, lf, argL0, argL1, argI2); 520 * } 521 * public final BoundMethodHandle copyWithExtendL(MethodType mt, LambdaForm lf, Object narg) { 522 * return SPECIES_DATA.extendWith(L_TYPE).constructor[0].invokeBasic(mt, lf, argL0, argL1, argI2, narg); 523 * } 524 * public final BoundMethodHandle copyWithExtendI(MethodType mt, LambdaForm lf, int narg) { 525 * return SPECIES_DATA.extendWith(I_TYPE).constructor[0].invokeBasic(mt, lf, argL0, argL1, argI2, narg); 526 * } 527 * public final BoundMethodHandle copyWithExtendJ(MethodType mt, LambdaForm lf, long narg) { 528 * return SPECIES_DATA.extendWith(J_TYPE).constructor[0].invokeBasic(mt, lf, argL0, argL1, argI2, narg); 529 * } 530 * public final BoundMethodHandle copyWithExtendF(MethodType mt, LambdaForm lf, float narg) { 531 * return SPECIES_DATA.extendWith(F_TYPE).constructor[0].invokeBasic(mt, lf, argL0, argL1, argI2, narg); 532 * } 533 * public final BoundMethodHandle copyWithExtendD(MethodType mt, LambdaForm lf, double narg) { 534 * return SPECIES_DATA.extendWith(D_TYPE).constructor[0].invokeBasic(mt, lf, argL0, argL1, argI2, narg); 535 * } 536 * } 537 * </pre> 538 * 539 * @param types the type signature, wherein reference types are erased to 'L' 540 * @return the generated concrete BMH class 541 */ 542 static Class<? extends BoundMethodHandle> generateConcreteBMHClass(String types) { 543 final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS + ClassWriter.COMPUTE_FRAMES); 544 545 String shortTypes = LambdaForm.shortenSignature(types); 546 final String className = SPECIES_PREFIX_PATH + shortTypes; 547 final String sourceFile = SPECIES_PREFIX_NAME + shortTypes; 548 cw.visit(V1_6, ACC_PUBLIC + ACC_FINAL + ACC_SUPER, className, null, BMH, null); 549 cw.visitSource(sourceFile, null); 550 551 // emit static types and SPECIES_DATA fields 552 cw.visitField(ACC_PUBLIC + ACC_STATIC, "SPECIES_DATA", SPECIES_DATA_SIG, null, null).visitEnd(); 553 554 // emit bound argument fields 555 for (int i = 0; i < types.length(); ++i) { 556 final char t = types.charAt(i); 557 final String fieldName = makeFieldName(types, i); 558 final String fieldDesc = t == 'L' ? JLO_SIG : String.valueOf(t); 559 cw.visitField(ACC_FINAL, fieldName, fieldDesc, null, null).visitEnd(); 560 } 561 562 MethodVisitor mv; 563 564 // emit constructor 565 mv = cw.visitMethod(ACC_PRIVATE, "<init>", makeSignature(types, true), null, null); 566 mv.visitCode(); 567 mv.visitVarInsn(ALOAD, 0); // this 568 mv.visitVarInsn(ALOAD, 1); // type 569 mv.visitVarInsn(ALOAD, 2); // form 570 571 mv.visitMethodInsn(INVOKESPECIAL, BMH, "<init>", makeSignature("", true), false); 572 573 for (int i = 0, j = 0; i < types.length(); ++i, ++j) { 574 // i counts the arguments, j counts corresponding argument slots 575 char t = types.charAt(i); 576 mv.visitVarInsn(ALOAD, 0); 577 mv.visitVarInsn(typeLoadOp(t), j + 3); // parameters start at 3 578 mv.visitFieldInsn(PUTFIELD, className, makeFieldName(types, i), typeSig(t)); 579 if (t == 'J' || t == 'D') { 580 ++j; // adjust argument register access 581 } 582 } 583 584 mv.visitInsn(RETURN); 585 mv.visitMaxs(0, 0); 586 mv.visitEnd(); 587 588 // emit implementation of speciesData() 589 mv = cw.visitMethod(ACC_PUBLIC + ACC_FINAL, "speciesData", MYSPECIES_DATA_SIG, null, null); 590 mv.visitCode(); 591 mv.visitFieldInsn(GETSTATIC, className, "SPECIES_DATA", SPECIES_DATA_SIG); 592 mv.visitInsn(ARETURN); 593 mv.visitMaxs(0, 0); 594 mv.visitEnd(); 595 596 // emit implementation of fieldCount() 597 mv = cw.visitMethod(ACC_PUBLIC + ACC_FINAL, "fieldCount", INT_SIG, null, null); 598 mv.visitCode(); 599 int fc = types.length(); 600 if (fc <= (ICONST_5 - ICONST_0)) { 601 mv.visitInsn(ICONST_0 + fc); 602 } else { 603 mv.visitIntInsn(SIPUSH, fc); 604 } 605 mv.visitInsn(IRETURN); 606 mv.visitMaxs(0, 0); 607 mv.visitEnd(); 608 // emit make() ...factory method wrapping constructor 609 mv = cw.visitMethod(ACC_PUBLIC + ACC_STATIC, "make", makeSignature(types, false), null, null); 610 mv.visitCode(); 611 // make instance 612 mv.visitTypeInsn(NEW, className); 613 mv.visitInsn(DUP); 614 // load mt, lf 615 mv.visitVarInsn(ALOAD, 0); // type 616 mv.visitVarInsn(ALOAD, 1); // form 617 // load factory method arguments 618 for (int i = 0, j = 0; i < types.length(); ++i, ++j) { 619 // i counts the arguments, j counts corresponding argument slots 620 char t = types.charAt(i); 621 mv.visitVarInsn(typeLoadOp(t), j + 2); // parameters start at 3 622 if (t == 'J' || t == 'D') { 623 ++j; // adjust argument register access 624 } 625 } 626 627 // finally, invoke the constructor and return 628 mv.visitMethodInsn(INVOKESPECIAL, className, "<init>", makeSignature(types, true)); 629 mv.visitInsn(ARETURN); 630 mv.visitMaxs(0, 0); 631 mv.visitEnd(); 632 633 // emit copyWith() 634 mv = cw.visitMethod(ACC_PUBLIC + ACC_FINAL, "copyWith", makeSignature("", false), null, null); 635 mv.visitCode(); 636 // make instance 637 mv.visitTypeInsn(NEW, className); 638 mv.visitInsn(DUP); 639 // load mt, lf 640 mv.visitVarInsn(ALOAD, 1); 641 mv.visitVarInsn(ALOAD, 2); 642 // put fields on the stack 643 emitPushFields(types, className, mv); 644 // finally, invoke the constructor and return 645 mv.visitMethodInsn(INVOKESPECIAL, className, "<init>", makeSignature(types, true)); 646 mv.visitInsn(ARETURN); 647 mv.visitMaxs(0, 0); 648 mv.visitEnd(); 649 650 // for each type, emit copyWithExtendT() 651 for (byte bt = 0; bt < ARG_TYPE_LIMIT; bt++) { 652 char t = basicTypeChar(bt); 653 mv = cw.visitMethod(ACC_PUBLIC + ACC_FINAL, "copyWithExtend" + t, makeSignature(String.valueOf(t), false), null, E_THROWABLE); 654 mv.visitCode(); 655 // return SPECIES_DATA.extendWith(t).constructor[0].invokeBasic(mt, lf, argL0, ..., narg) 656 // obtain constructor 657 mv.visitFieldInsn(GETSTATIC, className, "SPECIES_DATA", SPECIES_DATA_SIG); 658 int iconstInsn = ICONST_0 + bt; 659 assert(iconstInsn <= ICONST_5); 660 mv.visitInsn(iconstInsn); 661 mv.visitMethodInsn(INVOKEVIRTUAL, SPECIES_DATA, "extendWith", BMHSPECIES_DATA_EWI_SIG); 662 mv.visitFieldInsn(GETFIELD, SPECIES_DATA, "constructor", "[" + MH_SIG); 663 mv.visitInsn(ICONST_0); 664 mv.visitInsn(AALOAD); 665 // load mt, lf 666 mv.visitVarInsn(ALOAD, 1); 667 mv.visitVarInsn(ALOAD, 2); 668 // put fields on the stack 669 emitPushFields(types, className, mv); 670 // put narg on stack 671 mv.visitVarInsn(typeLoadOp(t), 3); 672 // finally, invoke the constructor and return 673 mv.visitMethodInsn(INVOKEVIRTUAL, MH, "invokeBasic", makeSignature(types + t, false), false); 674 mv.visitInsn(ARETURN); 675 mv.visitMaxs(0, 0); 676 mv.visitEnd(); 677 } 678 679 // emit class initializer 680 mv = cw.visitMethod(ACC_PUBLIC | ACC_STATIC, "<clinit>", VOID_SIG, null, null); 681 mv.visitCode(); 682 mv.visitLdcInsn(types); 683 mv.visitLdcInsn(Type.getObjectType(className)); 684 mv.visitMethodInsn(INVOKESTATIC, SPECIES_DATA, "getForClass", BMHSPECIES_DATA_GFC_SIG, false); 685 mv.visitFieldInsn(PUTSTATIC, className, "SPECIES_DATA", SPECIES_DATA_SIG); 686 mv.visitInsn(RETURN); 687 mv.visitMaxs(0, 0); 688 mv.visitEnd(); 689 690 cw.visitEnd(); 691 692 // load class 693 final byte[] classFile = cw.toByteArray(); 694 InvokerBytecodeGenerator.maybeDump(className, classFile); 695 Class<? extends BoundMethodHandle> bmhClass = 696 //UNSAFE.defineAnonymousClass(BoundMethodHandle.class, classFile, null).asSubclass(BoundMethodHandle.class); 697 UNSAFE.defineClass(className, classFile, 0, classFile.length, 698 BoundMethodHandle.class.getClassLoader(), null) 699 .asSubclass(BoundMethodHandle.class); 700 UNSAFE.ensureClassInitialized(bmhClass); 701 702 return bmhClass; 703 } 704 705 private static int typeLoadOp(char t) { 706 switch (t) { 707 case 'L': return ALOAD; 708 case 'I': return ILOAD; 709 case 'J': return LLOAD; 710 case 'F': return FLOAD; 711 case 'D': return DLOAD; 712 default : throw new InternalError("unrecognized type " + t); 713 } 714 } 715 716 private static void emitPushFields(String types, String className, MethodVisitor mv) { 717 for (int i = 0; i < types.length(); ++i) { 718 char tc = types.charAt(i); 719 mv.visitVarInsn(ALOAD, 0); 720 mv.visitFieldInsn(GETFIELD, className, makeFieldName(types, i), typeSig(tc)); 721 } 722 } 723 724 static String typeSig(char t) { 725 return t == 'L' ? JLO_SIG : String.valueOf(t); 726 } 727 728 // 729 // Getter MH generation. 730 // 731 732 private static MethodHandle makeGetter(Class<?> cbmhClass, String types, int index) { 733 String fieldName = makeFieldName(types, index); 734 Class<?> fieldType = Wrapper.forBasicType(types.charAt(index)).primitiveType(); 735 try { 736 return LOOKUP.findGetter(cbmhClass, fieldName, fieldType); 737 } catch (NoSuchFieldException | IllegalAccessException e) { 738 throw newInternalError(e); 739 } 740 } 741 742 static MethodHandle[] makeGetters(Class<?> cbmhClass, String types, MethodHandle[] mhs) { 743 if (mhs == null) mhs = new MethodHandle[types.length()]; 744 for (int i = 0; i < mhs.length; ++i) { 745 mhs[i] = makeGetter(cbmhClass, types, i); 746 assert(mhs[i].internalMemberName().getDeclaringClass() == cbmhClass); 747 } 748 return mhs; 749 } 750 751 static MethodHandle[] makeCtors(Class<? extends BoundMethodHandle> cbmh, String types, MethodHandle mhs[]) { 752 if (mhs == null) mhs = new MethodHandle[1]; 753 if (types.equals("")) return mhs; // hack for empty BMH species 754 mhs[0] = makeCbmhCtor(cbmh, types); 755 return mhs; 756 } 757 758 static NamedFunction[] makeNominalGetters(Class<?> cbmhClass, String types, NamedFunction[] nfs, MethodHandle[] getters) { 759 if (nfs == null) nfs = new NamedFunction[types.length()]; 760 for (int i = 0; i < nfs.length; ++i) { 761 nfs[i] = new NamedFunction(getters[i]); 762 } 763 return nfs; 764 } 765 766 // 767 // Auxiliary methods. 768 // 769 770 static SpeciesData speciesDataFromConcreteBMHClass(Class<? extends BoundMethodHandle> cbmh) { 771 try { 772 Field F_SPECIES_DATA = cbmh.getDeclaredField("SPECIES_DATA"); 773 return (SpeciesData) F_SPECIES_DATA.get(null); 774 } catch (ReflectiveOperationException ex) { 775 throw newInternalError(ex); 776 } 777 } 778 779 /** 780 * Field names in concrete BMHs adhere to this pattern: 781 * arg + type + index 782 * where type is a single character (L, I, J, F, D). 783 */ 784 private static String makeFieldName(String types, int index) { 785 assert index >= 0 && index < types.length(); 786 return "arg" + types.charAt(index) + index; 787 } 788 789 private static String makeSignature(String types, boolean ctor) { 790 StringBuilder buf = new StringBuilder(SIG_INCIPIT); 791 for (char c : types.toCharArray()) { 792 buf.append(typeSig(c)); 793 } 794 return buf.append(')').append(ctor ? "V" : BMH_SIG).toString(); 795 } 796 797 static MethodHandle makeCbmhCtor(Class<? extends BoundMethodHandle> cbmh, String types) { 798 try { 799 return LOOKUP.findStatic(cbmh, "make", MethodType.fromMethodDescriptorString(makeSignature(types, false), null)); 800 } catch (NoSuchMethodException | IllegalAccessException | IllegalArgumentException | TypeNotPresentException e) { 801 throw newInternalError(e); 802 } 803 } 804 } 805 806 private static final Lookup LOOKUP = Lookup.IMPL_LOOKUP; 807 808 static void initStatics() {} 809 static { SpeciesData.initStatics(); } 810 811 /** 812 * All subclasses must provide such a value describing their type signature. 813 */ 814 static final SpeciesData SPECIES_DATA = SpeciesData.EMPTY; 815 816 private static final SpeciesData[] SPECIES_DATA_CACHE = new SpeciesData[5]; 817 private static SpeciesData checkCache(int size, String types) { 818 int idx = size - 1; 819 SpeciesData data = SPECIES_DATA_CACHE[idx]; 820 if (data != null) return data; 821 SPECIES_DATA_CACHE[idx] = data = getSpeciesData(types); 822 return data; 823 } 824 static SpeciesData speciesData_L() { return checkCache(1, "L"); } 825 static SpeciesData speciesData_LL() { return checkCache(2, "LL"); } 826 static SpeciesData speciesData_LLL() { return checkCache(3, "LLL"); } 827 static SpeciesData speciesData_LLLL() { return checkCache(4, "LLLL"); } 828 static SpeciesData speciesData_LLLLL() { return checkCache(5, "LLLLL"); } 829 }