1 /* 2 * Copyright (c) 2011, 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 java.lang.annotation.*; 29 import java.lang.reflect.Method; 30 import java.util.List; 31 import java.util.Arrays; 32 import java.util.HashMap; 33 34 import sun.invoke.util.Wrapper; 35 import java.lang.reflect.Field; 36 37 import static java.lang.invoke.LambdaForm.BasicType.*; 38 import static java.lang.invoke.MethodHandleStatics.*; 39 import static java.lang.invoke.MethodHandleNatives.Constants.*; 40 41 /** 42 * The symbolic, non-executable form of a method handle's invocation semantics. 43 * It consists of a series of names. 44 * The first N (N=arity) names are parameters, 45 * while any remaining names are temporary values. 46 * Each temporary specifies the application of a function to some arguments. 47 * The functions are method handles, while the arguments are mixes of 48 * constant values and local names. 49 * The result of the lambda is defined as one of the names, often the last one. 50 * <p> 51 * Here is an approximate grammar: 52 * <blockquote><pre>{@code 53 * LambdaForm = "(" ArgName* ")=>{" TempName* Result "}" 54 * ArgName = "a" N ":" T 55 * TempName = "t" N ":" T "=" Function "(" Argument* ");" 56 * Function = ConstantValue 57 * Argument = NameRef | ConstantValue 58 * Result = NameRef | "void" 59 * NameRef = "a" N | "t" N 60 * N = (any whole number) 61 * T = "L" | "I" | "J" | "F" | "D" | "V" 62 * }</pre></blockquote> 63 * Names are numbered consecutively from left to right starting at zero. 64 * (The letters are merely a taste of syntax sugar.) 65 * Thus, the first temporary (if any) is always numbered N (where N=arity). 66 * Every occurrence of a name reference in an argument list must refer to 67 * a name previously defined within the same lambda. 68 * A lambda has a void result if and only if its result index is -1. 69 * If a temporary has the type "V", it cannot be the subject of a NameRef, 70 * even though possesses a number. 71 * Note that all reference types are erased to "L", which stands for {@code Object}. 72 * All subword types (boolean, byte, short, char) are erased to "I" which is {@code int}. 73 * The other types stand for the usual primitive types. 74 * <p> 75 * Function invocation closely follows the static rules of the Java verifier. 76 * Arguments and return values must exactly match when their "Name" types are 77 * considered. 78 * Conversions are allowed only if they do not change the erased type. 79 * <ul> 80 * <li>L = Object: casts are used freely to convert into and out of reference types 81 * <li>I = int: subword types are forcibly narrowed when passed as arguments (see {@code explicitCastArguments}) 82 * <li>J = long: no implicit conversions 83 * <li>F = float: no implicit conversions 84 * <li>D = double: no implicit conversions 85 * <li>V = void: a function result may be void if and only if its Name is of type "V" 86 * </ul> 87 * Although implicit conversions are not allowed, explicit ones can easily be 88 * encoded by using temporary expressions which call type-transformed identity functions. 89 * <p> 90 * Examples: 91 * <blockquote><pre>{@code 92 * (a0:J)=>{ a0 } 93 * == identity(long) 94 * (a0:I)=>{ t1:V = System.out#println(a0); void } 95 * == System.out#println(int) 96 * (a0:L)=>{ t1:V = System.out#println(a0); a0 } 97 * == identity, with printing side-effect 98 * (a0:L, a1:L)=>{ t2:L = BoundMethodHandle#argument(a0); 99 * t3:L = BoundMethodHandle#target(a0); 100 * t4:L = MethodHandle#invoke(t3, t2, a1); t4 } 101 * == general invoker for unary insertArgument combination 102 * (a0:L, a1:L)=>{ t2:L = FilterMethodHandle#filter(a0); 103 * t3:L = MethodHandle#invoke(t2, a1); 104 * t4:L = FilterMethodHandle#target(a0); 105 * t5:L = MethodHandle#invoke(t4, t3); t5 } 106 * == general invoker for unary filterArgument combination 107 * (a0:L, a1:L)=>{ ...(same as previous example)... 108 * t5:L = MethodHandle#invoke(t4, t3, a1); t5 } 109 * == general invoker for unary/unary foldArgument combination 110 * (a0:L, a1:I)=>{ t2:I = identity(long).asType((int)->long)(a1); t2 } 111 * == invoker for identity method handle which performs i2l 112 * (a0:L, a1:L)=>{ t2:L = BoundMethodHandle#argument(a0); 113 * t3:L = Class#cast(t2,a1); t3 } 114 * == invoker for identity method handle which performs cast 115 * }</pre></blockquote> 116 * <p> 117 * @author John Rose, JSR 292 EG 118 */ 119 class LambdaForm { 120 final int arity; 121 final int result; 122 final boolean forceInline; 123 @Stable final Name[] names; 124 final String debugName; 125 MemberName vmentry; // low-level behavior, or null if not yet prepared 126 private boolean isCompiled; 127 128 volatile Object transformCache; // managed by LambdaFormEditor 129 130 public static final int VOID_RESULT = -1, LAST_RESULT = -2; 131 132 enum BasicType { 133 L_TYPE('L', Object.class, Wrapper.OBJECT), // all reference types 134 I_TYPE('I', int.class, Wrapper.INT), 135 J_TYPE('J', long.class, Wrapper.LONG), 136 F_TYPE('F', float.class, Wrapper.FLOAT), 137 D_TYPE('D', double.class, Wrapper.DOUBLE), // all primitive types 138 V_TYPE('V', void.class, Wrapper.VOID); // not valid in all contexts 139 140 static final BasicType[] ALL_TYPES = BasicType.values(); 141 static final BasicType[] ARG_TYPES = Arrays.copyOf(ALL_TYPES, ALL_TYPES.length-1); 142 143 static final int ARG_TYPE_LIMIT = ARG_TYPES.length; 144 static final int TYPE_LIMIT = ALL_TYPES.length; 145 146 private final char btChar; 147 private final Class<?> btClass; 148 private final Wrapper btWrapper; 149 150 private BasicType(char btChar, Class<?> btClass, Wrapper wrapper) { 151 this.btChar = btChar; 152 this.btClass = btClass; 153 this.btWrapper = wrapper; 154 } 155 156 char basicTypeChar() { 157 return btChar; 158 } 159 Class<?> basicTypeClass() { 160 return btClass; 161 } 162 Wrapper basicTypeWrapper() { 163 return btWrapper; 164 } 165 int basicTypeSlots() { 166 return btWrapper.stackSlots(); 167 } 168 169 static BasicType basicType(byte type) { 170 return ALL_TYPES[type]; 171 } 172 static BasicType basicType(char type) { 173 switch (type) { 174 case 'L': return L_TYPE; 175 case 'I': return I_TYPE; 176 case 'J': return J_TYPE; 177 case 'F': return F_TYPE; 178 case 'D': return D_TYPE; 179 case 'V': return V_TYPE; 180 // all subword types are represented as ints 181 case 'Z': 182 case 'B': 183 case 'S': 184 case 'C': 185 return I_TYPE; 186 default: 187 throw newInternalError("Unknown type char: '"+type+"'"); 188 } 189 } 190 static BasicType basicType(Wrapper type) { 191 char c = type.basicTypeChar(); 192 return basicType(c); 193 } 194 static BasicType basicType(Class<?> type) { 195 if (!type.isPrimitive()) return L_TYPE; 196 return basicType(Wrapper.forPrimitiveType(type)); 197 } 198 199 static char basicTypeChar(Class<?> type) { 200 return basicType(type).btChar; 201 } 202 static BasicType[] basicTypes(List<Class<?>> types) { 203 BasicType[] btypes = new BasicType[types.size()]; 204 for (int i = 0; i < btypes.length; i++) { 205 btypes[i] = basicType(types.get(i)); 206 } 207 return btypes; 208 } 209 static BasicType[] basicTypes(String types) { 210 BasicType[] btypes = new BasicType[types.length()]; 211 for (int i = 0; i < btypes.length; i++) { 212 btypes[i] = basicType(types.charAt(i)); 213 } 214 return btypes; 215 } 216 static byte[] basicTypesOrd(BasicType[] btypes) { 217 byte[] ords = new byte[btypes.length]; 218 for (int i = 0; i < btypes.length; i++) { 219 ords[i] = (byte)btypes[i].ordinal(); 220 } 221 return ords; 222 } 223 static boolean isBasicTypeChar(char c) { 224 return "LIJFDV".indexOf(c) >= 0; 225 } 226 static boolean isArgBasicTypeChar(char c) { 227 return "LIJFD".indexOf(c) >= 0; 228 } 229 230 static { assert(checkBasicType()); } 231 private static boolean checkBasicType() { 232 for (int i = 0; i < ARG_TYPE_LIMIT; i++) { 233 assert ARG_TYPES[i].ordinal() == i; 234 assert ARG_TYPES[i] == ALL_TYPES[i]; 235 } 236 for (int i = 0; i < TYPE_LIMIT; i++) { 237 assert ALL_TYPES[i].ordinal() == i; 238 } 239 assert ALL_TYPES[TYPE_LIMIT - 1] == V_TYPE; 240 assert !Arrays.asList(ARG_TYPES).contains(V_TYPE); 241 return true; 242 } 243 } 244 245 LambdaForm(String debugName, 246 int arity, Name[] names, int result) { 247 this(debugName, arity, names, result, /*forceInline=*/true); 248 } 249 LambdaForm(String debugName, 250 int arity, Name[] names, int result, boolean forceInline) { 251 assert(namesOK(arity, names)); 252 this.arity = arity; 253 this.result = fixResult(result, names); 254 this.names = names.clone(); 255 this.debugName = fixDebugName(debugName); 256 this.forceInline = forceInline; 257 int maxOutArity = normalize(); 258 if (maxOutArity > MethodType.MAX_MH_INVOKER_ARITY) { 259 // Cannot use LF interpreter on very high arity expressions. 260 assert(maxOutArity <= MethodType.MAX_JVM_ARITY); 261 compileToBytecode(); 262 } 263 } 264 LambdaForm(String debugName, 265 int arity, Name[] names) { 266 this(debugName, arity, names, LAST_RESULT, /*forceInline=*/true); 267 } 268 LambdaForm(String debugName, 269 int arity, Name[] names, boolean forceInline) { 270 this(debugName, arity, names, LAST_RESULT, forceInline); 271 } 272 LambdaForm(String debugName, 273 Name[] formals, Name[] temps, Name result) { 274 this(debugName, 275 formals.length, buildNames(formals, temps, result), LAST_RESULT, /*forceInline=*/true); 276 } 277 LambdaForm(String debugName, 278 Name[] formals, Name[] temps, Name result, boolean forceInline) { 279 this(debugName, 280 formals.length, buildNames(formals, temps, result), LAST_RESULT, forceInline); 281 } 282 283 private static Name[] buildNames(Name[] formals, Name[] temps, Name result) { 284 int arity = formals.length; 285 int length = arity + temps.length + (result == null ? 0 : 1); 286 Name[] names = Arrays.copyOf(formals, length); 287 System.arraycopy(temps, 0, names, arity, temps.length); 288 if (result != null) 289 names[length - 1] = result; 290 return names; 291 } 292 293 private LambdaForm(String sig) { 294 // Make a blank lambda form, which returns a constant zero or null. 295 // It is used as a template for managing the invocation of similar forms that are non-empty. 296 // Called only from getPreparedForm. 297 assert(isValidSignature(sig)); 298 this.arity = signatureArity(sig); 299 this.result = (signatureReturn(sig) == V_TYPE ? -1 : arity); 300 this.names = buildEmptyNames(arity, sig); 301 this.debugName = "LF.zero"; 302 this.forceInline = true; 303 assert(nameRefsAreLegal()); 304 assert(isEmpty()); 305 assert(sig.equals(basicTypeSignature())) : sig + " != " + basicTypeSignature(); 306 } 307 308 private static Name[] buildEmptyNames(int arity, String basicTypeSignature) { 309 assert(isValidSignature(basicTypeSignature)); 310 int resultPos = arity + 1; // skip '_' 311 if (arity < 0 || basicTypeSignature.length() != resultPos+1) 312 throw new IllegalArgumentException("bad arity for "+basicTypeSignature); 313 int numRes = (basicType(basicTypeSignature.charAt(resultPos)) == V_TYPE ? 0 : 1); 314 Name[] names = arguments(numRes, basicTypeSignature.substring(0, arity)); 315 for (int i = 0; i < numRes; i++) { 316 Name zero = new Name(constantZero(basicType(basicTypeSignature.charAt(resultPos + i)))); 317 names[arity + i] = zero.newIndex(arity + i); 318 } 319 return names; 320 } 321 322 private static int fixResult(int result, Name[] names) { 323 if (result == LAST_RESULT) 324 result = names.length - 1; // might still be void 325 if (result >= 0 && names[result].type == V_TYPE) 326 result = VOID_RESULT; 327 return result; 328 } 329 330 private static String fixDebugName(String debugName) { 331 if (DEBUG_NAME_COUNTERS != null) { 332 int under = debugName.indexOf('_'); 333 int length = debugName.length(); 334 if (under < 0) under = length; 335 String debugNameStem = debugName.substring(0, under); 336 Integer ctr; 337 synchronized (DEBUG_NAME_COUNTERS) { 338 ctr = DEBUG_NAME_COUNTERS.get(debugNameStem); 339 if (ctr == null) ctr = 0; 340 DEBUG_NAME_COUNTERS.put(debugNameStem, ctr+1); 341 } 342 StringBuilder buf = new StringBuilder(debugNameStem); 343 buf.append('_'); 344 int leadingZero = buf.length(); 345 buf.append((int) ctr); 346 for (int i = buf.length() - leadingZero; i < 3; i++) 347 buf.insert(leadingZero, '0'); 348 if (under < length) { 349 ++under; // skip "_" 350 while (under < length && Character.isDigit(debugName.charAt(under))) { 351 ++under; 352 } 353 if (under < length && debugName.charAt(under) == '_') ++under; 354 if (under < length) 355 buf.append('_').append(debugName, under, length); 356 } 357 return buf.toString(); 358 } 359 return debugName; 360 } 361 362 private static boolean namesOK(int arity, Name[] names) { 363 for (int i = 0; i < names.length; i++) { 364 Name n = names[i]; 365 assert(n != null) : "n is null"; 366 if (i < arity) 367 assert( n.isParam()) : n + " is not param at " + i; 368 else 369 assert(!n.isParam()) : n + " is param at " + i; 370 } 371 return true; 372 } 373 374 /** Renumber and/or replace params so that they are interned and canonically numbered. 375 * @return maximum argument list length among the names (since we have to pass over them anyway) 376 */ 377 private int normalize() { 378 Name[] oldNames = null; 379 int maxOutArity = 0; 380 int changesStart = 0; 381 for (int i = 0; i < names.length; i++) { 382 Name n = names[i]; 383 if (!n.initIndex(i)) { 384 if (oldNames == null) { 385 oldNames = names.clone(); 386 changesStart = i; 387 } 388 names[i] = n.cloneWithIndex(i); 389 } 390 if (n.arguments != null && maxOutArity < n.arguments.length) 391 maxOutArity = n.arguments.length; 392 } 393 if (oldNames != null) { 394 int startFixing = arity; 395 if (startFixing <= changesStart) 396 startFixing = changesStart+1; 397 for (int i = startFixing; i < names.length; i++) { 398 Name fixed = names[i].replaceNames(oldNames, names, changesStart, i); 399 names[i] = fixed.newIndex(i); 400 } 401 } 402 assert(nameRefsAreLegal()); 403 int maxInterned = Math.min(arity, INTERNED_ARGUMENT_LIMIT); 404 boolean needIntern = false; 405 for (int i = 0; i < maxInterned; i++) { 406 Name n = names[i], n2 = internArgument(n); 407 if (n != n2) { 408 names[i] = n2; 409 needIntern = true; 410 } 411 } 412 if (needIntern) { 413 for (int i = arity; i < names.length; i++) { 414 names[i].internArguments(); 415 } 416 assert(nameRefsAreLegal()); 417 } 418 return maxOutArity; 419 } 420 421 /** 422 * Check that all embedded Name references are localizable to this lambda, 423 * and are properly ordered after their corresponding definitions. 424 * <p> 425 * Note that a Name can be local to multiple lambdas, as long as 426 * it possesses the same index in each use site. 427 * This allows Name references to be freely reused to construct 428 * fresh lambdas, without confusion. 429 */ 430 boolean nameRefsAreLegal() { 431 assert(arity >= 0 && arity <= names.length); 432 assert(result >= -1 && result < names.length); 433 // Do all names possess an index consistent with their local definition order? 434 for (int i = 0; i < arity; i++) { 435 Name n = names[i]; 436 assert(n.index() == i) : Arrays.asList(n.index(), i); 437 assert(n.isParam()); 438 } 439 // Also, do all local name references 440 for (int i = arity; i < names.length; i++) { 441 Name n = names[i]; 442 assert(n.index() == i); 443 for (Object arg : n.arguments) { 444 if (arg instanceof Name) { 445 Name n2 = (Name) arg; 446 int i2 = n2.index; 447 assert(0 <= i2 && i2 < names.length) : n.debugString() + ": 0 <= i2 && i2 < names.length: 0 <= " + i2 + " < " + names.length; 448 assert(names[i2] == n2) : Arrays.asList("-1-", i, "-2-", n.debugString(), "-3-", i2, "-4-", n2.debugString(), "-5-", names[i2].debugString(), "-6-", this); 449 assert(i2 < i); // ref must come after def! 450 } 451 } 452 } 453 return true; 454 } 455 456 /** Invoke this form on the given arguments. */ 457 // final Object invoke(Object... args) throws Throwable { 458 // // NYI: fit this into the fast path? 459 // return interpretWithArguments(args); 460 // } 461 462 /** Report the return type. */ 463 BasicType returnType() { 464 if (result < 0) return V_TYPE; 465 Name n = names[result]; 466 return n.type; 467 } 468 469 /** Report the N-th argument type. */ 470 BasicType parameterType(int n) { 471 return parameter(n).type; 472 } 473 474 /** Report the N-th argument name. */ 475 Name parameter(int n) { 476 assert(n < arity); 477 Name param = names[n]; 478 assert(param.isParam()); 479 return param; 480 } 481 482 /** Report the N-th argument type constraint. */ 483 Object parameterConstraint(int n) { 484 return parameter(n).constraint; 485 } 486 487 /** Report the arity. */ 488 int arity() { 489 return arity; 490 } 491 492 /** Report the number of expressions (non-parameter names). */ 493 int expressionCount() { 494 return names.length - arity; 495 } 496 497 /** Return the method type corresponding to my basic type signature. */ 498 MethodType methodType() { 499 return signatureType(basicTypeSignature()); 500 } 501 /** Return ABC_Z, where the ABC are parameter type characters, and Z is the return type character. */ 502 final String basicTypeSignature() { 503 StringBuilder buf = new StringBuilder(arity() + 3); 504 for (int i = 0, a = arity(); i < a; i++) 505 buf.append(parameterType(i).basicTypeChar()); 506 return buf.append('_').append(returnType().basicTypeChar()).toString(); 507 } 508 static int signatureArity(String sig) { 509 assert(isValidSignature(sig)); 510 return sig.indexOf('_'); 511 } 512 static BasicType signatureReturn(String sig) { 513 return basicType(sig.charAt(signatureArity(sig) + 1)); 514 } 515 static boolean isValidSignature(String sig) { 516 int arity = sig.indexOf('_'); 517 if (arity < 0) return false; // must be of the form *_* 518 int siglen = sig.length(); 519 if (siglen != arity + 2) return false; // *_X 520 for (int i = 0; i < siglen; i++) { 521 if (i == arity) continue; // skip '_' 522 char c = sig.charAt(i); 523 if (c == 'V') 524 return (i == siglen - 1 && arity == siglen - 2); 525 if (!isArgBasicTypeChar(c)) return false; // must be [LIJFD] 526 } 527 return true; // [LIJFD]*_[LIJFDV] 528 } 529 static MethodType signatureType(String sig) { 530 Class<?>[] ptypes = new Class<?>[signatureArity(sig)]; 531 for (int i = 0; i < ptypes.length; i++) 532 ptypes[i] = basicType(sig.charAt(i)).btClass; 533 Class<?> rtype = signatureReturn(sig).btClass; 534 return MethodType.methodType(rtype, ptypes); 535 } 536 537 /* 538 * Code generation issues: 539 * 540 * Compiled LFs should be reusable in general. 541 * The biggest issue is how to decide when to pull a name into 542 * the bytecode, versus loading a reified form from the MH data. 543 * 544 * For example, an asType wrapper may require execution of a cast 545 * after a call to a MH. The target type of the cast can be placed 546 * as a constant in the LF itself. This will force the cast type 547 * to be compiled into the bytecodes and native code for the MH. 548 * Or, the target type of the cast can be erased in the LF, and 549 * loaded from the MH data. (Later on, if the MH as a whole is 550 * inlined, the data will flow into the inlined instance of the LF, 551 * as a constant, and the end result will be an optimal cast.) 552 * 553 * This erasure of cast types can be done with any use of 554 * reference types. It can also be done with whole method 555 * handles. Erasing a method handle might leave behind 556 * LF code that executes correctly for any MH of a given 557 * type, and load the required MH from the enclosing MH's data. 558 * Or, the erasure might even erase the expected MT. 559 * 560 * Also, for direct MHs, the MemberName of the target 561 * could be erased, and loaded from the containing direct MH. 562 * As a simple case, a LF for all int-valued non-static 563 * field getters would perform a cast on its input argument 564 * (to non-constant base type derived from the MemberName) 565 * and load an integer value from the input object 566 * (at a non-constant offset also derived from the MemberName). 567 * Such MN-erased LFs would be inlinable back to optimized 568 * code, whenever a constant enclosing DMH is available 569 * to supply a constant MN from its data. 570 * 571 * The main problem here is to keep LFs reasonably generic, 572 * while ensuring that hot spots will inline good instances. 573 * "Reasonably generic" means that we don't end up with 574 * repeated versions of bytecode or machine code that do 575 * not differ in their optimized form. Repeated versions 576 * of machine would have the undesirable overheads of 577 * (a) redundant compilation work and (b) extra I$ pressure. 578 * To control repeated versions, we need to be ready to 579 * erase details from LFs and move them into MH data, 580 * whevener those details are not relevant to significant 581 * optimization. "Significant" means optimization of 582 * code that is actually hot. 583 * 584 * Achieving this may require dynamic splitting of MHs, by replacing 585 * a generic LF with a more specialized one, on the same MH, 586 * if (a) the MH is frequently executed and (b) the MH cannot 587 * be inlined into a containing caller, such as an invokedynamic. 588 * 589 * Compiled LFs that are no longer used should be GC-able. 590 * If they contain non-BCP references, they should be properly 591 * interlinked with the class loader(s) that their embedded types 592 * depend on. This probably means that reusable compiled LFs 593 * will be tabulated (indexed) on relevant class loaders, 594 * or else that the tables that cache them will have weak links. 595 */ 596 597 /** 598 * Make this LF directly executable, as part of a MethodHandle. 599 * Invariant: Every MH which is invoked must prepare its LF 600 * before invocation. 601 * (In principle, the JVM could do this very lazily, 602 * as a sort of pre-invocation linkage step.) 603 */ 604 public void prepare() { 605 if (COMPILE_THRESHOLD == 0) { 606 compileToBytecode(); 607 } 608 if (this.vmentry != null) { 609 // already prepared (e.g., a primitive DMH invoker form) 610 return; 611 } 612 LambdaForm prep = getPreparedForm(basicTypeSignature()); 613 this.vmentry = prep.vmentry; 614 // TO DO: Maybe add invokeGeneric, invokeWithArguments 615 } 616 617 /** Generate optimizable bytecode for this form. */ 618 MemberName compileToBytecode() { 619 MethodType invokerType = methodType(); 620 assert(vmentry == null || vmentry.getMethodType().basicType().equals(invokerType)); 621 if (vmentry != null && isCompiled) { 622 return vmentry; // already compiled somehow 623 } 624 try { 625 vmentry = InvokerBytecodeGenerator.generateCustomizedCode(this, invokerType); 626 if (TRACE_INTERPRETER) 627 traceInterpreter("compileToBytecode", this); 628 isCompiled = true; 629 return vmentry; 630 } catch (Error | Exception ex) { 631 throw newInternalError(this.toString(), ex); 632 } 633 } 634 635 private static void computeInitialPreparedForms() { 636 // Find all predefined invokers and associate them with canonical empty lambda forms. 637 for (MemberName m : MemberName.getFactory().getMethods(LambdaForm.class, false, null, null, null)) { 638 if (!m.isStatic() || !m.isPackage()) continue; 639 MethodType mt = m.getMethodType(); 640 if (mt.parameterCount() > 0 && 641 mt.parameterType(0) == MethodHandle.class && 642 m.getName().startsWith("interpret_")) { 643 String sig = basicTypeSignature(mt); 644 assert(m.getName().equals("interpret" + sig.substring(sig.indexOf('_')))); 645 LambdaForm form = new LambdaForm(sig); 646 form.vmentry = m; 647 form = mt.form().setCachedLambdaForm(MethodTypeForm.LF_INTERPRET, form); 648 } 649 } 650 } 651 652 // Set this false to disable use of the interpret_L methods defined in this file. 653 private static final boolean USE_PREDEFINED_INTERPRET_METHODS = true; 654 655 // The following are predefined exact invokers. The system must build 656 // a separate invoker for each distinct signature. 657 static Object interpret_L(MethodHandle mh) throws Throwable { 658 Object[] av = {mh}; 659 String sig = null; 660 assert(argumentTypesMatch(sig = "L_L", av)); 661 Object res = mh.form.interpretWithArguments(av); 662 assert(returnTypesMatch(sig, av, res)); 663 return res; 664 } 665 static Object interpret_L(MethodHandle mh, Object x1) throws Throwable { 666 Object[] av = {mh, x1}; 667 String sig = null; 668 assert(argumentTypesMatch(sig = "LL_L", av)); 669 Object res = mh.form.interpretWithArguments(av); 670 assert(returnTypesMatch(sig, av, res)); 671 return res; 672 } 673 static Object interpret_L(MethodHandle mh, Object x1, Object x2) throws Throwable { 674 Object[] av = {mh, x1, x2}; 675 String sig = null; 676 assert(argumentTypesMatch(sig = "LLL_L", av)); 677 Object res = mh.form.interpretWithArguments(av); 678 assert(returnTypesMatch(sig, av, res)); 679 return res; 680 } 681 private static LambdaForm getPreparedForm(String sig) { 682 MethodType mtype = signatureType(sig); 683 LambdaForm prep = mtype.form().cachedLambdaForm(MethodTypeForm.LF_INTERPRET); 684 if (prep != null) return prep; 685 assert(isValidSignature(sig)); 686 prep = new LambdaForm(sig); 687 prep.vmentry = InvokerBytecodeGenerator.generateLambdaFormInterpreterEntryPoint(sig); 688 return mtype.form().setCachedLambdaForm(MethodTypeForm.LF_INTERPRET, prep); 689 } 690 691 // The next few routines are called only from assert expressions 692 // They verify that the built-in invokers process the correct raw data types. 693 private static boolean argumentTypesMatch(String sig, Object[] av) { 694 int arity = signatureArity(sig); 695 assert(av.length == arity) : "av.length == arity: av.length=" + av.length + ", arity=" + arity; 696 assert(av[0] instanceof MethodHandle) : "av[0] not instace of MethodHandle: " + av[0]; 697 MethodHandle mh = (MethodHandle) av[0]; 698 MethodType mt = mh.type(); 699 assert(mt.parameterCount() == arity-1); 700 for (int i = 0; i < av.length; i++) { 701 Class<?> pt = (i == 0 ? MethodHandle.class : mt.parameterType(i-1)); 702 assert(valueMatches(basicType(sig.charAt(i)), pt, av[i])); 703 } 704 return true; 705 } 706 private static boolean valueMatches(BasicType tc, Class<?> type, Object x) { 707 // The following line is needed because (...)void method handles can use non-void invokers 708 if (type == void.class) tc = V_TYPE; // can drop any kind of value 709 assert tc == basicType(type) : tc + " == basicType(" + type + ")=" + basicType(type); 710 switch (tc) { 711 case I_TYPE: assert checkInt(type, x) : "checkInt(" + type + "," + x +")"; break; 712 case J_TYPE: assert x instanceof Long : "instanceof Long: " + x; break; 713 case F_TYPE: assert x instanceof Float : "instanceof Float: " + x; break; 714 case D_TYPE: assert x instanceof Double : "instanceof Double: " + x; break; 715 case L_TYPE: assert checkRef(type, x) : "checkRef(" + type + "," + x + ")"; break; 716 case V_TYPE: break; // allow anything here; will be dropped 717 default: assert(false); 718 } 719 return true; 720 } 721 private static boolean returnTypesMatch(String sig, Object[] av, Object res) { 722 MethodHandle mh = (MethodHandle) av[0]; 723 return valueMatches(signatureReturn(sig), mh.type().returnType(), res); 724 } 725 private static boolean checkInt(Class<?> type, Object x) { 726 assert(x instanceof Integer); 727 if (type == int.class) return true; 728 Wrapper w = Wrapper.forBasicType(type); 729 assert(w.isSubwordOrInt()); 730 Object x1 = Wrapper.INT.wrap(w.wrap(x)); 731 return x.equals(x1); 732 } 733 private static boolean checkRef(Class<?> type, Object x) { 734 assert(!type.isPrimitive()); 735 if (x == null) return true; 736 if (type.isInterface()) return true; 737 return type.isInstance(x); 738 } 739 740 /** If the invocation count hits the threshold we spin bytecodes and call that subsequently. */ 741 private static final int COMPILE_THRESHOLD; 742 static { 743 COMPILE_THRESHOLD = Math.max(-1, MethodHandleStatics.COMPILE_THRESHOLD); 744 } 745 private int invocationCounter = 0; 746 747 @Hidden 748 @DontInline 749 /** Interpretively invoke this form on the given arguments. */ 750 Object interpretWithArguments(Object... argumentValues) throws Throwable { 751 if (TRACE_INTERPRETER) 752 return interpretWithArgumentsTracing(argumentValues); 753 checkInvocationCounter(); 754 assert(arityCheck(argumentValues)); 755 Object[] values = Arrays.copyOf(argumentValues, names.length); 756 for (int i = argumentValues.length; i < values.length; i++) { 757 values[i] = interpretName(names[i], values); 758 } 759 Object rv = (result < 0) ? null : values[result]; 760 assert(resultCheck(argumentValues, rv)); 761 return rv; 762 } 763 764 @Hidden 765 @DontInline 766 /** Evaluate a single Name within this form, applying its function to its arguments. */ 767 Object interpretName(Name name, Object[] values) throws Throwable { 768 if (TRACE_INTERPRETER) 769 traceInterpreter("| interpretName", name.debugString(), (Object[]) null); 770 Object[] arguments = Arrays.copyOf(name.arguments, name.arguments.length, Object[].class); 771 for (int i = 0; i < arguments.length; i++) { 772 Object a = arguments[i]; 773 if (a instanceof Name) { 774 int i2 = ((Name)a).index(); 775 assert(names[i2] == a); 776 a = values[i2]; 777 arguments[i] = a; 778 } 779 } 780 return name.function.invokeWithArguments(arguments); 781 } 782 783 private void checkInvocationCounter() { 784 if (COMPILE_THRESHOLD != 0 && 785 invocationCounter < COMPILE_THRESHOLD) { 786 invocationCounter++; // benign race 787 if (invocationCounter >= COMPILE_THRESHOLD) { 788 // Replace vmentry with a bytecode version of this LF. 789 compileToBytecode(); 790 } 791 } 792 } 793 Object interpretWithArgumentsTracing(Object... argumentValues) throws Throwable { 794 traceInterpreter("[ interpretWithArguments", this, argumentValues); 795 if (invocationCounter < COMPILE_THRESHOLD) { 796 int ctr = invocationCounter++; // benign race 797 traceInterpreter("| invocationCounter", ctr); 798 if (invocationCounter >= COMPILE_THRESHOLD) { 799 compileToBytecode(); 800 } 801 } 802 Object rval; 803 try { 804 assert(arityCheck(argumentValues)); 805 Object[] values = Arrays.copyOf(argumentValues, names.length); 806 for (int i = argumentValues.length; i < values.length; i++) { 807 values[i] = interpretName(names[i], values); 808 } 809 rval = (result < 0) ? null : values[result]; 810 } catch (Throwable ex) { 811 traceInterpreter("] throw =>", ex); 812 throw ex; 813 } 814 traceInterpreter("] return =>", rval); 815 return rval; 816 } 817 818 static void traceInterpreter(String event, Object obj, Object... args) { 819 if (TRACE_INTERPRETER) { 820 System.out.println("LFI: "+event+" "+(obj != null ? obj : "")+(args != null && args.length != 0 ? Arrays.asList(args) : "")); 821 } 822 } 823 static void traceInterpreter(String event, Object obj) { 824 traceInterpreter(event, obj, (Object[])null); 825 } 826 private boolean arityCheck(Object[] argumentValues) { 827 assert(argumentValues.length == arity) : arity+"!="+Arrays.asList(argumentValues)+".length"; 828 // also check that the leading (receiver) argument is somehow bound to this LF: 829 assert(argumentValues[0] instanceof MethodHandle) : "not MH: " + argumentValues[0]; 830 MethodHandle mh = (MethodHandle) argumentValues[0]; 831 assert(mh.internalForm() == this); 832 // note: argument #0 could also be an interface wrapper, in the future 833 argumentTypesMatch(basicTypeSignature(), argumentValues); 834 return true; 835 } 836 private boolean resultCheck(Object[] argumentValues, Object result) { 837 MethodHandle mh = (MethodHandle) argumentValues[0]; 838 MethodType mt = mh.type(); 839 assert(valueMatches(returnType(), mt.returnType(), result)); 840 return true; 841 } 842 843 private boolean isEmpty() { 844 if (result < 0) 845 return (names.length == arity); 846 else if (result == arity && names.length == arity + 1) 847 return names[arity].isConstantZero(); 848 else 849 return false; 850 } 851 852 public String toString() { 853 StringBuilder buf = new StringBuilder(debugName+"=Lambda("); 854 for (int i = 0; i < names.length; i++) { 855 if (i == arity) buf.append(")=>{"); 856 Name n = names[i]; 857 if (i >= arity) buf.append("\n "); 858 buf.append(n.paramString()); 859 if (i < arity) { 860 if (i+1 < arity) buf.append(","); 861 continue; 862 } 863 buf.append("=").append(n.exprString()); 864 buf.append(";"); 865 } 866 if (arity == names.length) buf.append(")=>{"); 867 buf.append(result < 0 ? "void" : names[result]).append("}"); 868 if (TRACE_INTERPRETER) { 869 // Extra verbosity: 870 buf.append(":").append(basicTypeSignature()); 871 buf.append("/").append(vmentry); 872 } 873 return buf.toString(); 874 } 875 876 @Override 877 public boolean equals(Object obj) { 878 return obj instanceof LambdaForm && equals((LambdaForm)obj); 879 } 880 public boolean equals(LambdaForm that) { 881 if (this.result != that.result) return false; 882 return Arrays.equals(this.names, that.names); 883 } 884 public int hashCode() { 885 return result + 31 * Arrays.hashCode(names); 886 } 887 LambdaFormEditor editor() { 888 return LambdaFormEditor.lambdaFormEditor(this); 889 } 890 891 boolean contains(Name name) { 892 int pos = name.index(); 893 if (pos >= 0) { 894 return pos < names.length && name.equals(names[pos]); 895 } 896 for (int i = arity; i < names.length; i++) { 897 if (name.equals(names[i])) 898 return true; 899 } 900 return false; 901 } 902 903 LambdaForm addArguments(int pos, BasicType... types) { 904 // names array has MH in slot 0; skip it. 905 int argpos = pos + 1; 906 assert(argpos <= arity); 907 int length = names.length; 908 int inTypes = types.length; 909 Name[] names2 = Arrays.copyOf(names, length + inTypes); 910 int arity2 = arity + inTypes; 911 int result2 = result; 912 if (result2 >= argpos) 913 result2 += inTypes; 914 // Note: The LF constructor will rename names2[argpos...]. 915 // Make space for new arguments (shift temporaries). 916 System.arraycopy(names, argpos, names2, argpos + inTypes, length - argpos); 917 for (int i = 0; i < inTypes; i++) { 918 names2[argpos + i] = new Name(types[i]); 919 } 920 return new LambdaForm(debugName, arity2, names2, result2); 921 } 922 923 LambdaForm addArguments(int pos, List<Class<?>> types) { 924 return addArguments(pos, basicTypes(types)); 925 } 926 927 LambdaForm permuteArguments(int skip, int[] reorder, BasicType[] types) { 928 // Note: When inArg = reorder[outArg], outArg is fed by a copy of inArg. 929 // The types are the types of the new (incoming) arguments. 930 int length = names.length; 931 int inTypes = types.length; 932 int outArgs = reorder.length; 933 assert(skip+outArgs == arity); 934 assert(permutedTypesMatch(reorder, types, names, skip)); 935 int pos = 0; 936 // skip trivial first part of reordering: 937 while (pos < outArgs && reorder[pos] == pos) pos += 1; 938 Name[] names2 = new Name[length - outArgs + inTypes]; 939 System.arraycopy(names, 0, names2, 0, skip+pos); 940 // copy the body: 941 int bodyLength = length - arity; 942 System.arraycopy(names, skip+outArgs, names2, skip+inTypes, bodyLength); 943 int arity2 = names2.length - bodyLength; 944 int result2 = result; 945 if (result2 >= 0) { 946 if (result2 < skip+outArgs) { 947 // return the corresponding inArg 948 result2 = reorder[result2-skip]; 949 } else { 950 result2 = result2 - outArgs + inTypes; 951 } 952 } 953 // rework names in the body: 954 for (int j = pos; j < outArgs; j++) { 955 Name n = names[skip+j]; 956 int i = reorder[j]; 957 // replace names[skip+j] by names2[skip+i] 958 Name n2 = names2[skip+i]; 959 if (n2 == null) 960 names2[skip+i] = n2 = new Name(types[i]); 961 else 962 assert(n2.type == types[i]); 963 for (int k = arity2; k < names2.length; k++) { 964 names2[k] = names2[k].replaceName(n, n2); 965 } 966 } 967 // some names are unused, but must be filled in 968 for (int i = skip+pos; i < arity2; i++) { 969 if (names2[i] == null) 970 names2[i] = argument(i, types[i - skip]); 971 } 972 for (int j = arity; j < names.length; j++) { 973 int i = j - arity + arity2; 974 // replace names2[i] by names[j] 975 Name n = names[j]; 976 Name n2 = names2[i]; 977 if (n != n2) { 978 for (int k = i+1; k < names2.length; k++) { 979 names2[k] = names2[k].replaceName(n, n2); 980 } 981 } 982 } 983 return new LambdaForm(debugName, arity2, names2, result2); 984 } 985 986 static boolean permutedTypesMatch(int[] reorder, BasicType[] types, Name[] names, int skip) { 987 int inTypes = types.length; 988 int outArgs = reorder.length; 989 for (int i = 0; i < outArgs; i++) { 990 assert(names[skip+i].isParam()); 991 assert(names[skip+i].type == types[reorder[i]]); 992 } 993 return true; 994 } 995 996 static class NamedFunction { 997 final MemberName member; 998 @Stable MethodHandle resolvedHandle; 999 @Stable MethodHandle invoker; 1000 1001 NamedFunction(MethodHandle resolvedHandle) { 1002 this(resolvedHandle.internalMemberName(), resolvedHandle); 1003 } 1004 NamedFunction(MemberName member, MethodHandle resolvedHandle) { 1005 this.member = member; 1006 this.resolvedHandle = resolvedHandle; 1007 // The following assert is almost always correct, but will fail for corner cases, such as PrivateInvokeTest. 1008 //assert(!isInvokeBasic()); 1009 } 1010 NamedFunction(MethodType basicInvokerType) { 1011 assert(basicInvokerType == basicInvokerType.basicType()) : basicInvokerType; 1012 if (basicInvokerType.parameterSlotCount() < MethodType.MAX_MH_INVOKER_ARITY) { 1013 this.resolvedHandle = basicInvokerType.invokers().basicInvoker(); 1014 this.member = resolvedHandle.internalMemberName(); 1015 } else { 1016 // necessary to pass BigArityTest 1017 this.member = Invokers.invokeBasicMethod(basicInvokerType); 1018 } 1019 assert(isInvokeBasic()); 1020 } 1021 1022 private boolean isInvokeBasic() { 1023 return member != null && 1024 member.isMethodHandleInvoke() && 1025 "invokeBasic".equals(member.getName()); 1026 } 1027 1028 // The next 3 constructors are used to break circular dependencies on MH.invokeStatic, etc. 1029 // Any LambdaForm containing such a member is not interpretable. 1030 // This is OK, since all such LFs are prepared with special primitive vmentry points. 1031 // And even without the resolvedHandle, the name can still be compiled and optimized. 1032 NamedFunction(Method method) { 1033 this(new MemberName(method)); 1034 } 1035 NamedFunction(Field field) { 1036 this(new MemberName(field)); 1037 } 1038 NamedFunction(MemberName member) { 1039 this.member = member; 1040 this.resolvedHandle = null; 1041 } 1042 1043 MethodHandle resolvedHandle() { 1044 if (resolvedHandle == null) resolve(); 1045 return resolvedHandle; 1046 } 1047 1048 void resolve() { 1049 resolvedHandle = DirectMethodHandle.make(member); 1050 } 1051 1052 @Override 1053 public boolean equals(Object other) { 1054 if (this == other) return true; 1055 if (other == null) return false; 1056 if (!(other instanceof NamedFunction)) return false; 1057 NamedFunction that = (NamedFunction) other; 1058 return this.member != null && this.member.equals(that.member); 1059 } 1060 1061 @Override 1062 public int hashCode() { 1063 if (member != null) 1064 return member.hashCode(); 1065 return super.hashCode(); 1066 } 1067 1068 // Put the predefined NamedFunction invokers into the table. 1069 static void initializeInvokers() { 1070 for (MemberName m : MemberName.getFactory().getMethods(NamedFunction.class, false, null, null, null)) { 1071 if (!m.isStatic() || !m.isPackage()) continue; 1072 MethodType type = m.getMethodType(); 1073 if (type.equals(INVOKER_METHOD_TYPE) && 1074 m.getName().startsWith("invoke_")) { 1075 String sig = m.getName().substring("invoke_".length()); 1076 int arity = LambdaForm.signatureArity(sig); 1077 MethodType srcType = MethodType.genericMethodType(arity); 1078 if (LambdaForm.signatureReturn(sig) == V_TYPE) 1079 srcType = srcType.changeReturnType(void.class); 1080 MethodTypeForm typeForm = srcType.form(); 1081 typeForm.setCachedMethodHandle(MethodTypeForm.MH_NF_INV, DirectMethodHandle.make(m)); 1082 } 1083 } 1084 } 1085 1086 // The following are predefined NamedFunction invokers. The system must build 1087 // a separate invoker for each distinct signature. 1088 /** void return type invokers. */ 1089 @Hidden 1090 static Object invoke__V(MethodHandle mh, Object[] a) throws Throwable { 1091 assert(arityCheck(0, void.class, mh, a)); 1092 mh.invokeBasic(); 1093 return null; 1094 } 1095 @Hidden 1096 static Object invoke_L_V(MethodHandle mh, Object[] a) throws Throwable { 1097 assert(arityCheck(1, void.class, mh, a)); 1098 mh.invokeBasic(a[0]); 1099 return null; 1100 } 1101 @Hidden 1102 static Object invoke_LL_V(MethodHandle mh, Object[] a) throws Throwable { 1103 assert(arityCheck(2, void.class, mh, a)); 1104 mh.invokeBasic(a[0], a[1]); 1105 return null; 1106 } 1107 @Hidden 1108 static Object invoke_LLL_V(MethodHandle mh, Object[] a) throws Throwable { 1109 assert(arityCheck(3, void.class, mh, a)); 1110 mh.invokeBasic(a[0], a[1], a[2]); 1111 return null; 1112 } 1113 @Hidden 1114 static Object invoke_LLLL_V(MethodHandle mh, Object[] a) throws Throwable { 1115 assert(arityCheck(4, void.class, mh, a)); 1116 mh.invokeBasic(a[0], a[1], a[2], a[3]); 1117 return null; 1118 } 1119 @Hidden 1120 static Object invoke_LLLLL_V(MethodHandle mh, Object[] a) throws Throwable { 1121 assert(arityCheck(5, void.class, mh, a)); 1122 mh.invokeBasic(a[0], a[1], a[2], a[3], a[4]); 1123 return null; 1124 } 1125 /** Object return type invokers. */ 1126 @Hidden 1127 static Object invoke__L(MethodHandle mh, Object[] a) throws Throwable { 1128 assert(arityCheck(0, mh, a)); 1129 return mh.invokeBasic(); 1130 } 1131 @Hidden 1132 static Object invoke_L_L(MethodHandle mh, Object[] a) throws Throwable { 1133 assert(arityCheck(1, mh, a)); 1134 return mh.invokeBasic(a[0]); 1135 } 1136 @Hidden 1137 static Object invoke_LL_L(MethodHandle mh, Object[] a) throws Throwable { 1138 assert(arityCheck(2, mh, a)); 1139 return mh.invokeBasic(a[0], a[1]); 1140 } 1141 @Hidden 1142 static Object invoke_LLL_L(MethodHandle mh, Object[] a) throws Throwable { 1143 assert(arityCheck(3, mh, a)); 1144 return mh.invokeBasic(a[0], a[1], a[2]); 1145 } 1146 @Hidden 1147 static Object invoke_LLLL_L(MethodHandle mh, Object[] a) throws Throwable { 1148 assert(arityCheck(4, mh, a)); 1149 return mh.invokeBasic(a[0], a[1], a[2], a[3]); 1150 } 1151 @Hidden 1152 static Object invoke_LLLLL_L(MethodHandle mh, Object[] a) throws Throwable { 1153 assert(arityCheck(5, mh, a)); 1154 return mh.invokeBasic(a[0], a[1], a[2], a[3], a[4]); 1155 } 1156 private static boolean arityCheck(int arity, MethodHandle mh, Object[] a) { 1157 return arityCheck(arity, Object.class, mh, a); 1158 } 1159 private static boolean arityCheck(int arity, Class<?> rtype, MethodHandle mh, Object[] a) { 1160 assert(a.length == arity) 1161 : Arrays.asList(a.length, arity); 1162 assert(mh.type().basicType() == MethodType.genericMethodType(arity).changeReturnType(rtype)) 1163 : Arrays.asList(mh, rtype, arity); 1164 MemberName member = mh.internalMemberName(); 1165 if (member != null && member.getName().equals("invokeBasic") && member.isMethodHandleInvoke()) { 1166 assert(arity > 0); 1167 assert(a[0] instanceof MethodHandle); 1168 MethodHandle mh2 = (MethodHandle) a[0]; 1169 assert(mh2.type().basicType() == MethodType.genericMethodType(arity-1).changeReturnType(rtype)) 1170 : Arrays.asList(member, mh2, rtype, arity); 1171 } 1172 return true; 1173 } 1174 1175 static final MethodType INVOKER_METHOD_TYPE = 1176 MethodType.methodType(Object.class, MethodHandle.class, Object[].class); 1177 1178 private static MethodHandle computeInvoker(MethodTypeForm typeForm) { 1179 typeForm = typeForm.basicType().form(); // normalize to basic type 1180 MethodHandle mh = typeForm.cachedMethodHandle(MethodTypeForm.MH_NF_INV); 1181 if (mh != null) return mh; 1182 MemberName invoker = InvokerBytecodeGenerator.generateNamedFunctionInvoker(typeForm); // this could take a while 1183 mh = DirectMethodHandle.make(invoker); 1184 MethodHandle mh2 = typeForm.cachedMethodHandle(MethodTypeForm.MH_NF_INV); 1185 if (mh2 != null) return mh2; // benign race 1186 if (!mh.type().equals(INVOKER_METHOD_TYPE)) 1187 throw newInternalError(mh.debugString()); 1188 return typeForm.setCachedMethodHandle(MethodTypeForm.MH_NF_INV, mh); 1189 } 1190 1191 @Hidden 1192 Object invokeWithArguments(Object... arguments) throws Throwable { 1193 // If we have a cached invoker, call it right away. 1194 // NOTE: The invoker always returns a reference value. 1195 if (TRACE_INTERPRETER) return invokeWithArgumentsTracing(arguments); 1196 assert(checkArgumentTypes(arguments, methodType())); 1197 return invoker().invokeBasic(resolvedHandle(), arguments); 1198 } 1199 1200 @Hidden 1201 Object invokeWithArgumentsTracing(Object[] arguments) throws Throwable { 1202 Object rval; 1203 try { 1204 traceInterpreter("[ call", this, arguments); 1205 if (invoker == null) { 1206 traceInterpreter("| getInvoker", this); 1207 invoker(); 1208 } 1209 if (resolvedHandle == null) { 1210 traceInterpreter("| resolve", this); 1211 resolvedHandle(); 1212 } 1213 assert(checkArgumentTypes(arguments, methodType())); 1214 rval = invoker().invokeBasic(resolvedHandle(), arguments); 1215 } catch (Throwable ex) { 1216 traceInterpreter("] throw =>", ex); 1217 throw ex; 1218 } 1219 traceInterpreter("] return =>", rval); 1220 return rval; 1221 } 1222 1223 private MethodHandle invoker() { 1224 if (invoker != null) return invoker; 1225 // Get an invoker and cache it. 1226 return invoker = computeInvoker(methodType().form()); 1227 } 1228 1229 private static boolean checkArgumentTypes(Object[] arguments, MethodType methodType) { 1230 if (true) return true; // FIXME 1231 MethodType dstType = methodType.form().erasedType(); 1232 MethodType srcType = dstType.basicType().wrap(); 1233 Class<?>[] ptypes = new Class<?>[arguments.length]; 1234 for (int i = 0; i < arguments.length; i++) { 1235 Object arg = arguments[i]; 1236 Class<?> ptype = arg == null ? Object.class : arg.getClass(); 1237 // If the dest. type is a primitive we keep the 1238 // argument type. 1239 ptypes[i] = dstType.parameterType(i).isPrimitive() ? ptype : Object.class; 1240 } 1241 MethodType argType = MethodType.methodType(srcType.returnType(), ptypes).wrap(); 1242 assert(argType.isConvertibleTo(srcType)) : "wrong argument types: cannot convert " + argType + " to " + srcType; 1243 return true; 1244 } 1245 1246 MethodType methodType() { 1247 if (resolvedHandle != null) 1248 return resolvedHandle.type(); 1249 else 1250 // only for certain internal LFs during bootstrapping 1251 return member.getInvocationType(); 1252 } 1253 1254 MemberName member() { 1255 assert(assertMemberIsConsistent()); 1256 return member; 1257 } 1258 1259 // Called only from assert. 1260 private boolean assertMemberIsConsistent() { 1261 if (resolvedHandle instanceof DirectMethodHandle) { 1262 MemberName m = resolvedHandle.internalMemberName(); 1263 assert(m.equals(member)); 1264 } 1265 return true; 1266 } 1267 1268 Class<?> memberDeclaringClassOrNull() { 1269 return (member == null) ? null : member.getDeclaringClass(); 1270 } 1271 1272 BasicType returnType() { 1273 return basicType(methodType().returnType()); 1274 } 1275 1276 BasicType parameterType(int n) { 1277 return basicType(methodType().parameterType(n)); 1278 } 1279 1280 int arity() { 1281 return methodType().parameterCount(); 1282 } 1283 1284 public String toString() { 1285 if (member == null) return String.valueOf(resolvedHandle); 1286 return member.getDeclaringClass().getSimpleName()+"."+member.getName(); 1287 } 1288 1289 public boolean isIdentity() { 1290 return this.equals(identity(returnType())); 1291 } 1292 1293 public boolean isConstantZero() { 1294 return this.equals(constantZero(returnType())); 1295 } 1296 1297 public MethodHandleImpl.Intrinsic intrinsicName() { 1298 return resolvedHandle == null ? MethodHandleImpl.Intrinsic.NONE 1299 : resolvedHandle.intrinsicName(); 1300 } 1301 } 1302 1303 public static String basicTypeSignature(MethodType type) { 1304 char[] sig = new char[type.parameterCount() + 2]; 1305 int sigp = 0; 1306 for (Class<?> pt : type.parameterList()) { 1307 sig[sigp++] = basicTypeChar(pt); 1308 } 1309 sig[sigp++] = '_'; 1310 sig[sigp++] = basicTypeChar(type.returnType()); 1311 assert(sigp == sig.length); 1312 return String.valueOf(sig); 1313 } 1314 public static String shortenSignature(String signature) { 1315 // Hack to make signatures more readable when they show up in method names. 1316 final int NO_CHAR = -1, MIN_RUN = 3; 1317 int c0, c1 = NO_CHAR, c1reps = 0; 1318 StringBuilder buf = null; 1319 int len = signature.length(); 1320 if (len < MIN_RUN) return signature; 1321 for (int i = 0; i <= len; i++) { 1322 // shift in the next char: 1323 c0 = c1; c1 = (i == len ? NO_CHAR : signature.charAt(i)); 1324 if (c1 == c0) { ++c1reps; continue; } 1325 // shift in the next count: 1326 int c0reps = c1reps; c1reps = 1; 1327 // end of a character run 1328 if (c0reps < MIN_RUN) { 1329 if (buf != null) { 1330 while (--c0reps >= 0) 1331 buf.append((char)c0); 1332 } 1333 continue; 1334 } 1335 // found three or more in a row 1336 if (buf == null) 1337 buf = new StringBuilder().append(signature, 0, i - c0reps); 1338 buf.append((char)c0).append(c0reps); 1339 } 1340 return (buf == null) ? signature : buf.toString(); 1341 } 1342 1343 static final class Name { 1344 final BasicType type; 1345 private short index; 1346 final NamedFunction function; 1347 final Object constraint; // additional type information, if not null 1348 @Stable final Object[] arguments; 1349 1350 private Name(int index, BasicType type, NamedFunction function, Object[] arguments) { 1351 this.index = (short)index; 1352 this.type = type; 1353 this.function = function; 1354 this.arguments = arguments; 1355 this.constraint = null; 1356 assert(this.index == index); 1357 } 1358 private Name(Name that, Object constraint) { 1359 this.index = that.index; 1360 this.type = that.type; 1361 this.function = that.function; 1362 this.arguments = that.arguments; 1363 this.constraint = constraint; 1364 assert(constraint == null || isParam()); // only params have constraints 1365 assert(constraint == null || constraint instanceof BoundMethodHandle.SpeciesData || constraint instanceof Class); 1366 } 1367 Name(MethodHandle function, Object... arguments) { 1368 this(new NamedFunction(function), arguments); 1369 } 1370 Name(MethodType functionType, Object... arguments) { 1371 this(new NamedFunction(functionType), arguments); 1372 assert(arguments[0] instanceof Name && ((Name)arguments[0]).type == L_TYPE); 1373 } 1374 Name(MemberName function, Object... arguments) { 1375 this(new NamedFunction(function), arguments); 1376 } 1377 Name(NamedFunction function, Object... arguments) { 1378 this(-1, function.returnType(), function, arguments = Arrays.copyOf(arguments, arguments.length, Object[].class)); 1379 assert(arguments.length == function.arity()) : "arity mismatch: arguments.length=" + arguments.length + " == function.arity()=" + function.arity() + " in " + debugString(); 1380 for (int i = 0; i < arguments.length; i++) 1381 assert(typesMatch(function.parameterType(i), arguments[i])) : "types don't match: function.parameterType(" + i + ")=" + function.parameterType(i) + ", arguments[" + i + "]=" + arguments[i] + " in " + debugString(); 1382 } 1383 /** Create a raw parameter of the given type, with an expected index. */ 1384 Name(int index, BasicType type) { 1385 this(index, type, null, null); 1386 } 1387 /** Create a raw parameter of the given type. */ 1388 Name(BasicType type) { this(-1, type); } 1389 1390 BasicType type() { return type; } 1391 int index() { return index; } 1392 boolean initIndex(int i) { 1393 if (index != i) { 1394 if (index != -1) return false; 1395 index = (short)i; 1396 } 1397 return true; 1398 } 1399 char typeChar() { 1400 return type.btChar; 1401 } 1402 1403 void resolve() { 1404 if (function != null) 1405 function.resolve(); 1406 } 1407 1408 Name newIndex(int i) { 1409 if (initIndex(i)) return this; 1410 return cloneWithIndex(i); 1411 } 1412 Name cloneWithIndex(int i) { 1413 Object[] newArguments = (arguments == null) ? null : arguments.clone(); 1414 return new Name(i, type, function, newArguments).withConstraint(constraint); 1415 } 1416 Name withConstraint(Object constraint) { 1417 if (constraint == this.constraint) return this; 1418 return new Name(this, constraint); 1419 } 1420 Name replaceName(Name oldName, Name newName) { // FIXME: use replaceNames uniformly 1421 if (oldName == newName) return this; 1422 @SuppressWarnings("LocalVariableHidesMemberVariable") 1423 Object[] arguments = this.arguments; 1424 if (arguments == null) return this; 1425 boolean replaced = false; 1426 for (int j = 0; j < arguments.length; j++) { 1427 if (arguments[j] == oldName) { 1428 if (!replaced) { 1429 replaced = true; 1430 arguments = arguments.clone(); 1431 } 1432 arguments[j] = newName; 1433 } 1434 } 1435 if (!replaced) return this; 1436 return new Name(function, arguments); 1437 } 1438 /** In the arguments of this Name, replace oldNames[i] pairwise by newNames[i]. 1439 * Limit such replacements to {@code start<=i<end}. Return possibly changed self. 1440 */ 1441 Name replaceNames(Name[] oldNames, Name[] newNames, int start, int end) { 1442 if (start >= end) return this; 1443 @SuppressWarnings("LocalVariableHidesMemberVariable") 1444 Object[] arguments = this.arguments; 1445 boolean replaced = false; 1446 eachArg: 1447 for (int j = 0; j < arguments.length; j++) { 1448 if (arguments[j] instanceof Name) { 1449 Name n = (Name) arguments[j]; 1450 int check = n.index; 1451 // harmless check to see if the thing is already in newNames: 1452 if (check >= 0 && check < newNames.length && n == newNames[check]) 1453 continue eachArg; 1454 // n might not have the correct index: n != oldNames[n.index]. 1455 for (int i = start; i < end; i++) { 1456 if (n == oldNames[i]) { 1457 if (n == newNames[i]) 1458 continue eachArg; 1459 if (!replaced) { 1460 replaced = true; 1461 arguments = arguments.clone(); 1462 } 1463 arguments[j] = newNames[i]; 1464 continue eachArg; 1465 } 1466 } 1467 } 1468 } 1469 if (!replaced) return this; 1470 return new Name(function, arguments); 1471 } 1472 void internArguments() { 1473 @SuppressWarnings("LocalVariableHidesMemberVariable") 1474 Object[] arguments = this.arguments; 1475 for (int j = 0; j < arguments.length; j++) { 1476 if (arguments[j] instanceof Name) { 1477 Name n = (Name) arguments[j]; 1478 if (n.isParam() && n.index < INTERNED_ARGUMENT_LIMIT) 1479 arguments[j] = internArgument(n); 1480 } 1481 } 1482 } 1483 boolean isParam() { 1484 return function == null; 1485 } 1486 boolean isConstantZero() { 1487 return !isParam() && arguments.length == 0 && function.isConstantZero(); 1488 } 1489 1490 public String toString() { 1491 return (isParam()?"a":"t")+(index >= 0 ? index : System.identityHashCode(this))+":"+typeChar(); 1492 } 1493 public String debugString() { 1494 String s = paramString(); 1495 return (function == null) ? s : s + "=" + exprString(); 1496 } 1497 public String paramString() { 1498 String s = toString(); 1499 Object c = constraint; 1500 if (c == null) 1501 return s; 1502 if (c instanceof Class) c = ((Class<?>)c).getSimpleName(); 1503 return s + "/" + c; 1504 } 1505 public String exprString() { 1506 if (function == null) return toString(); 1507 StringBuilder buf = new StringBuilder(function.toString()); 1508 buf.append("("); 1509 String cma = ""; 1510 for (Object a : arguments) { 1511 buf.append(cma); cma = ","; 1512 if (a instanceof Name || a instanceof Integer) 1513 buf.append(a); 1514 else 1515 buf.append("(").append(a).append(")"); 1516 } 1517 buf.append(")"); 1518 return buf.toString(); 1519 } 1520 1521 static boolean typesMatch(BasicType parameterType, Object object) { 1522 if (object instanceof Name) { 1523 return ((Name)object).type == parameterType; 1524 } 1525 switch (parameterType) { 1526 case I_TYPE: return object instanceof Integer; 1527 case J_TYPE: return object instanceof Long; 1528 case F_TYPE: return object instanceof Float; 1529 case D_TYPE: return object instanceof Double; 1530 } 1531 assert(parameterType == L_TYPE); 1532 return true; 1533 } 1534 1535 /** Return the index of the last occurrence of n in the argument array. 1536 * Return -1 if the name is not used. 1537 */ 1538 int lastUseIndex(Name n) { 1539 if (arguments == null) return -1; 1540 for (int i = arguments.length; --i >= 0; ) { 1541 if (arguments[i] == n) return i; 1542 } 1543 return -1; 1544 } 1545 1546 /** Return the number of occurrences of n in the argument array. 1547 * Return 0 if the name is not used. 1548 */ 1549 int useCount(Name n) { 1550 if (arguments == null) return 0; 1551 int count = 0; 1552 for (int i = arguments.length; --i >= 0; ) { 1553 if (arguments[i] == n) ++count; 1554 } 1555 return count; 1556 } 1557 1558 boolean contains(Name n) { 1559 return this == n || lastUseIndex(n) >= 0; 1560 } 1561 1562 public boolean equals(Name that) { 1563 if (this == that) return true; 1564 if (isParam()) 1565 // each parameter is a unique atom 1566 return false; // this != that 1567 return 1568 //this.index == that.index && 1569 this.type == that.type && 1570 this.function.equals(that.function) && 1571 Arrays.equals(this.arguments, that.arguments); 1572 } 1573 @Override 1574 public boolean equals(Object x) { 1575 return x instanceof Name && equals((Name)x); 1576 } 1577 @Override 1578 public int hashCode() { 1579 if (isParam()) 1580 return index | (type.ordinal() << 8); 1581 return function.hashCode() ^ Arrays.hashCode(arguments); 1582 } 1583 } 1584 1585 /** Return the index of the last name which contains n as an argument. 1586 * Return -1 if the name is not used. Return names.length if it is the return value. 1587 */ 1588 int lastUseIndex(Name n) { 1589 int ni = n.index, nmax = names.length; 1590 assert(names[ni] == n); 1591 if (result == ni) return nmax; // live all the way beyond the end 1592 for (int i = nmax; --i > ni; ) { 1593 if (names[i].lastUseIndex(n) >= 0) 1594 return i; 1595 } 1596 return -1; 1597 } 1598 1599 /** Return the number of times n is used as an argument or return value. */ 1600 int useCount(Name n) { 1601 int ni = n.index, nmax = names.length; 1602 int end = lastUseIndex(n); 1603 if (end < 0) return 0; 1604 int count = 0; 1605 if (end == nmax) { count++; end--; } 1606 int beg = n.index() + 1; 1607 if (beg < arity) beg = arity; 1608 for (int i = beg; i <= end; i++) { 1609 count += names[i].useCount(n); 1610 } 1611 return count; 1612 } 1613 1614 static Name argument(int which, char type) { 1615 return argument(which, basicType(type)); 1616 } 1617 static Name argument(int which, BasicType type) { 1618 if (which >= INTERNED_ARGUMENT_LIMIT) 1619 return new Name(which, type); 1620 return INTERNED_ARGUMENTS[type.ordinal()][which]; 1621 } 1622 static Name internArgument(Name n) { 1623 assert(n.isParam()) : "not param: " + n; 1624 assert(n.index < INTERNED_ARGUMENT_LIMIT); 1625 if (n.constraint != null) return n; 1626 return argument(n.index, n.type); 1627 } 1628 static Name[] arguments(int extra, String types) { 1629 int length = types.length(); 1630 Name[] names = new Name[length + extra]; 1631 for (int i = 0; i < length; i++) 1632 names[i] = argument(i, types.charAt(i)); 1633 return names; 1634 } 1635 static Name[] arguments(int extra, char... types) { 1636 int length = types.length; 1637 Name[] names = new Name[length + extra]; 1638 for (int i = 0; i < length; i++) 1639 names[i] = argument(i, types[i]); 1640 return names; 1641 } 1642 static Name[] arguments(int extra, List<Class<?>> types) { 1643 int length = types.size(); 1644 Name[] names = new Name[length + extra]; 1645 for (int i = 0; i < length; i++) 1646 names[i] = argument(i, basicType(types.get(i))); 1647 return names; 1648 } 1649 static Name[] arguments(int extra, Class<?>... types) { 1650 int length = types.length; 1651 Name[] names = new Name[length + extra]; 1652 for (int i = 0; i < length; i++) 1653 names[i] = argument(i, basicType(types[i])); 1654 return names; 1655 } 1656 static Name[] arguments(int extra, MethodType types) { 1657 int length = types.parameterCount(); 1658 Name[] names = new Name[length + extra]; 1659 for (int i = 0; i < length; i++) 1660 names[i] = argument(i, basicType(types.parameterType(i))); 1661 return names; 1662 } 1663 static final int INTERNED_ARGUMENT_LIMIT = 10; 1664 private static final Name[][] INTERNED_ARGUMENTS 1665 = new Name[ARG_TYPE_LIMIT][INTERNED_ARGUMENT_LIMIT]; 1666 static { 1667 for (BasicType type : BasicType.ARG_TYPES) { 1668 int ord = type.ordinal(); 1669 for (int i = 0; i < INTERNED_ARGUMENTS[ord].length; i++) { 1670 INTERNED_ARGUMENTS[ord][i] = new Name(i, type); 1671 } 1672 } 1673 } 1674 1675 private static final MemberName.Factory IMPL_NAMES = MemberName.getFactory(); 1676 1677 static LambdaForm identityForm(BasicType type) { 1678 return LF_identityForm[type.ordinal()]; 1679 } 1680 static LambdaForm zeroForm(BasicType type) { 1681 return LF_zeroForm[type.ordinal()]; 1682 } 1683 static NamedFunction identity(BasicType type) { 1684 return NF_identity[type.ordinal()]; 1685 } 1686 static NamedFunction constantZero(BasicType type) { 1687 return NF_zero[type.ordinal()]; 1688 } 1689 private static final LambdaForm[] LF_identityForm = new LambdaForm[TYPE_LIMIT]; 1690 private static final LambdaForm[] LF_zeroForm = new LambdaForm[TYPE_LIMIT]; 1691 private static final NamedFunction[] NF_identity = new NamedFunction[TYPE_LIMIT]; 1692 private static final NamedFunction[] NF_zero = new NamedFunction[TYPE_LIMIT]; 1693 private static void createIdentityForms() { 1694 for (BasicType type : BasicType.ALL_TYPES) { 1695 int ord = type.ordinal(); 1696 char btChar = type.basicTypeChar(); 1697 boolean isVoid = (type == V_TYPE); 1698 Class<?> btClass = type.btClass; 1699 MethodType zeType = MethodType.methodType(btClass); 1700 MethodType idType = isVoid ? zeType : zeType.appendParameterTypes(btClass); 1701 1702 // Look up some symbolic names. It might not be necessary to have these, 1703 // but if we need to emit direct references to bytecodes, it helps. 1704 // Zero is built from a call to an identity function with a constant zero input. 1705 MemberName idMem = new MemberName(LambdaForm.class, "identity_"+btChar, idType, REF_invokeStatic); 1706 MemberName zeMem = new MemberName(LambdaForm.class, "zero_"+btChar, zeType, REF_invokeStatic); 1707 try { 1708 zeMem = IMPL_NAMES.resolveOrFail(REF_invokeStatic, zeMem, null, NoSuchMethodException.class); 1709 idMem = IMPL_NAMES.resolveOrFail(REF_invokeStatic, idMem, null, NoSuchMethodException.class); 1710 } catch (IllegalAccessException|NoSuchMethodException ex) { 1711 throw newInternalError(ex); 1712 } 1713 1714 NamedFunction idFun = new NamedFunction(idMem); 1715 LambdaForm idForm; 1716 if (isVoid) { 1717 Name[] idNames = new Name[] { argument(0, L_TYPE) }; 1718 idForm = new LambdaForm(idMem.getName(), 1, idNames, VOID_RESULT); 1719 } else { 1720 Name[] idNames = new Name[] { argument(0, L_TYPE), argument(1, type) }; 1721 idForm = new LambdaForm(idMem.getName(), 2, idNames, 1); 1722 } 1723 LF_identityForm[ord] = idForm; 1724 NF_identity[ord] = idFun; 1725 1726 NamedFunction zeFun = new NamedFunction(zeMem); 1727 LambdaForm zeForm; 1728 if (isVoid) { 1729 zeForm = idForm; 1730 } else { 1731 Object zeValue = Wrapper.forBasicType(btChar).zero(); 1732 Name[] zeNames = new Name[] { argument(0, L_TYPE), new Name(idFun, zeValue) }; 1733 zeForm = new LambdaForm(zeMem.getName(), 1, zeNames, 1); 1734 } 1735 LF_zeroForm[ord] = zeForm; 1736 NF_zero[ord] = zeFun; 1737 1738 assert(idFun.isIdentity()); 1739 assert(zeFun.isConstantZero()); 1740 assert(new Name(zeFun).isConstantZero()); 1741 } 1742 1743 // Do this in a separate pass, so that SimpleMethodHandle.make can see the tables. 1744 for (BasicType type : BasicType.ALL_TYPES) { 1745 int ord = type.ordinal(); 1746 NamedFunction idFun = NF_identity[ord]; 1747 LambdaForm idForm = LF_identityForm[ord]; 1748 MemberName idMem = idFun.member; 1749 idFun.resolvedHandle = SimpleMethodHandle.make(idMem.getInvocationType(), idForm); 1750 1751 NamedFunction zeFun = NF_zero[ord]; 1752 LambdaForm zeForm = LF_zeroForm[ord]; 1753 MemberName zeMem = zeFun.member; 1754 zeFun.resolvedHandle = SimpleMethodHandle.make(zeMem.getInvocationType(), zeForm); 1755 1756 assert(idFun.isIdentity()); 1757 assert(zeFun.isConstantZero()); 1758 assert(new Name(zeFun).isConstantZero()); 1759 } 1760 } 1761 1762 // Avoid appealing to ValueConversions at bootstrap time: 1763 private static int identity_I(int x) { return x; } 1764 private static long identity_J(long x) { return x; } 1765 private static float identity_F(float x) { return x; } 1766 private static double identity_D(double x) { return x; } 1767 private static Object identity_L(Object x) { return x; } 1768 private static void identity_V() { return; } // same as zeroV, but that's OK 1769 private static int zero_I() { return 0; } 1770 private static long zero_J() { return 0; } 1771 private static float zero_F() { return 0; } 1772 private static double zero_D() { return 0; } 1773 private static Object zero_L() { return null; } 1774 private static void zero_V() { return; } 1775 1776 /** 1777 * Internal marker for byte-compiled LambdaForms. 1778 */ 1779 /*non-public*/ 1780 @Target(ElementType.METHOD) 1781 @Retention(RetentionPolicy.RUNTIME) 1782 @interface Compiled { 1783 } 1784 1785 /** 1786 * Internal marker for LambdaForm interpreter frames. 1787 */ 1788 /*non-public*/ 1789 @Target(ElementType.METHOD) 1790 @Retention(RetentionPolicy.RUNTIME) 1791 @interface Hidden { 1792 } 1793 1794 /** 1795 * Internal marker which signals JIT that gathered profile is mostly useless. 1796 */ 1797 /*non-public*/ 1798 @Target(ElementType.METHOD) 1799 @Retention(RetentionPolicy.RUNTIME) 1800 @interface Shared { 1801 } 1802 1803 private static final HashMap<String,Integer> DEBUG_NAME_COUNTERS; 1804 static { 1805 if (debugEnabled()) 1806 DEBUG_NAME_COUNTERS = new HashMap<>(); 1807 else 1808 DEBUG_NAME_COUNTERS = null; 1809 } 1810 1811 // Put this last, so that previous static inits can run before. 1812 static { 1813 createIdentityForms(); 1814 if (USE_PREDEFINED_INTERPRET_METHODS) 1815 computeInitialPreparedForms(); 1816 NamedFunction.initializeInvokers(); 1817 } 1818 1819 // The following hack is necessary in order to suppress TRACE_INTERPRETER 1820 // during execution of the static initializes of this class. 1821 // Turning on TRACE_INTERPRETER too early will cause 1822 // stack overflows and other misbehavior during attempts to trace events 1823 // that occur during LambdaForm.<clinit>. 1824 // Therefore, do not move this line higher in this file, and do not remove. 1825 private static final boolean TRACE_INTERPRETER = MethodHandleStatics.TRACE_INTERPRETER; 1826 }