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 final MethodHandle customized; 124 @Stable final Name[] names; 125 final String debugName; 126 MemberName vmentry; // low-level behavior, or null if not yet prepared 127 private boolean isCompiled; 128 129 volatile Object transformCache; // managed by LambdaFormEditor 130 131 public static final int VOID_RESULT = -1, LAST_RESULT = -2; 132 133 enum BasicType { 134 L_TYPE('L', Object.class, Wrapper.OBJECT), // all reference types 135 I_TYPE('I', int.class, Wrapper.INT), 136 J_TYPE('J', long.class, Wrapper.LONG), 137 F_TYPE('F', float.class, Wrapper.FLOAT), 138 D_TYPE('D', double.class, Wrapper.DOUBLE), // all primitive types 139 V_TYPE('V', void.class, Wrapper.VOID); // not valid in all contexts 140 141 static final BasicType[] ALL_TYPES = BasicType.values(); 142 static final BasicType[] ARG_TYPES = Arrays.copyOf(ALL_TYPES, ALL_TYPES.length-1); 143 144 static final int ARG_TYPE_LIMIT = ARG_TYPES.length; 145 static final int TYPE_LIMIT = ALL_TYPES.length; 146 147 private final char btChar; 148 private final Class<?> btClass; 149 private final Wrapper btWrapper; 150 151 private BasicType(char btChar, Class<?> btClass, Wrapper wrapper) { 152 this.btChar = btChar; 153 this.btClass = btClass; 154 this.btWrapper = wrapper; 155 } 156 157 char basicTypeChar() { 158 return btChar; 159 } 160 Class<?> basicTypeClass() { 161 return btClass; 162 } 163 Wrapper basicTypeWrapper() { 164 return btWrapper; 165 } 166 int basicTypeSlots() { 167 return btWrapper.stackSlots(); 168 } 169 170 static BasicType basicType(byte type) { 171 return ALL_TYPES[type]; 172 } 173 static BasicType basicType(char type) { 174 switch (type) { 175 case 'L': return L_TYPE; 176 case 'I': return I_TYPE; 177 case 'J': return J_TYPE; 178 case 'F': return F_TYPE; 179 case 'D': return D_TYPE; 180 case 'V': return V_TYPE; 181 // all subword types are represented as ints 182 case 'Z': 183 case 'B': 184 case 'S': 185 case 'C': 186 return I_TYPE; 187 default: 188 throw newInternalError("Unknown type char: '"+type+"'"); 189 } 190 } 191 static BasicType basicType(Wrapper type) { 192 char c = type.basicTypeChar(); 193 return basicType(c); 194 } 195 static BasicType basicType(Class<?> type) { 196 if (!type.isPrimitive()) return L_TYPE; 197 return basicType(Wrapper.forPrimitiveType(type)); 198 } 199 200 static char basicTypeChar(Class<?> type) { 201 return basicType(type).btChar; 202 } 203 static BasicType[] basicTypes(List<Class<?>> types) { 204 BasicType[] btypes = new BasicType[types.size()]; 205 for (int i = 0; i < btypes.length; i++) { 206 btypes[i] = basicType(types.get(i)); 207 } 208 return btypes; 209 } 210 static BasicType[] basicTypes(String types) { 211 BasicType[] btypes = new BasicType[types.length()]; 212 for (int i = 0; i < btypes.length; i++) { 213 btypes[i] = basicType(types.charAt(i)); 214 } 215 return btypes; 216 } 217 static byte[] basicTypesOrd(BasicType[] btypes) { 218 byte[] ords = new byte[btypes.length]; 219 for (int i = 0; i < btypes.length; i++) { 220 ords[i] = (byte)btypes[i].ordinal(); 221 } 222 return ords; 223 } 224 static boolean isBasicTypeChar(char c) { 225 return "LIJFDV".indexOf(c) >= 0; 226 } 227 static boolean isArgBasicTypeChar(char c) { 228 return "LIJFD".indexOf(c) >= 0; 229 } 230 231 static { assert(checkBasicType()); } 232 private static boolean checkBasicType() { 233 for (int i = 0; i < ARG_TYPE_LIMIT; i++) { 234 assert ARG_TYPES[i].ordinal() == i; 235 assert ARG_TYPES[i] == ALL_TYPES[i]; 236 } 237 for (int i = 0; i < TYPE_LIMIT; i++) { 238 assert ALL_TYPES[i].ordinal() == i; 239 } 240 assert ALL_TYPES[TYPE_LIMIT - 1] == V_TYPE; 241 assert !Arrays.asList(ARG_TYPES).contains(V_TYPE); 242 return true; 243 } 244 } 245 246 LambdaForm(String debugName, 247 int arity, Name[] names, int result) { 248 this(debugName, arity, names, result, /*forceInline=*/true, /*customized=*/null); 249 } 250 LambdaForm(String debugName, 251 int arity, Name[] names, int result, boolean forceInline, MethodHandle customized) { 252 assert(namesOK(arity, names)); 253 this.arity = arity; 254 this.result = fixResult(result, names); 255 this.names = names.clone(); 256 this.debugName = fixDebugName(debugName); 257 this.forceInline = forceInline; 258 this.customized = customized; 259 int maxOutArity = normalize(); 260 if (maxOutArity > MethodType.MAX_MH_INVOKER_ARITY) { 261 // Cannot use LF interpreter on very high arity expressions. 262 assert(maxOutArity <= MethodType.MAX_JVM_ARITY); 263 compileToBytecode(); 264 } 265 } 266 LambdaForm(String debugName, 267 int arity, Name[] names) { 268 this(debugName, arity, names, LAST_RESULT, /*forceInline=*/true, /*customized=*/null); 269 } 270 LambdaForm(String debugName, 271 int arity, Name[] names, boolean forceInline) { 272 this(debugName, arity, names, LAST_RESULT, forceInline, /*customized=*/null); 273 } 274 LambdaForm(String debugName, 275 Name[] formals, Name[] temps, Name result) { 276 this(debugName, 277 formals.length, buildNames(formals, temps, result), LAST_RESULT, /*forceInline=*/true, /*customized=*/null); 278 } 279 LambdaForm(String debugName, 280 Name[] formals, Name[] temps, Name result, boolean forceInline) { 281 this(debugName, 282 formals.length, buildNames(formals, temps, result), LAST_RESULT, forceInline, /*customized=*/null); 283 } 284 285 private static Name[] buildNames(Name[] formals, Name[] temps, Name result) { 286 int arity = formals.length; 287 int length = arity + temps.length + (result == null ? 0 : 1); 288 Name[] names = Arrays.copyOf(formals, length); 289 System.arraycopy(temps, 0, names, arity, temps.length); 290 if (result != null) 291 names[length - 1] = result; 292 return names; 293 } 294 295 private LambdaForm(String sig) { 296 // Make a blank lambda form, which returns a constant zero or null. 297 // It is used as a template for managing the invocation of similar forms that are non-empty. 298 // Called only from getPreparedForm. 299 assert(isValidSignature(sig)); 300 this.arity = signatureArity(sig); 301 this.result = (signatureReturn(sig) == V_TYPE ? -1 : arity); 302 this.names = buildEmptyNames(arity, sig); 303 this.debugName = "LF.zero"; 304 this.forceInline = true; 305 this.customized = null; 306 assert(nameRefsAreLegal()); 307 assert(isEmpty()); 308 assert(sig.equals(basicTypeSignature())) : sig + " != " + basicTypeSignature(); 309 } 310 311 private static Name[] buildEmptyNames(int arity, String basicTypeSignature) { 312 assert(isValidSignature(basicTypeSignature)); 313 int resultPos = arity + 1; // skip '_' 314 if (arity < 0 || basicTypeSignature.length() != resultPos+1) 315 throw new IllegalArgumentException("bad arity for "+basicTypeSignature); 316 int numRes = (basicType(basicTypeSignature.charAt(resultPos)) == V_TYPE ? 0 : 1); 317 Name[] names = arguments(numRes, basicTypeSignature.substring(0, arity)); 318 for (int i = 0; i < numRes; i++) { 319 Name zero = new Name(constantZero(basicType(basicTypeSignature.charAt(resultPos + i)))); 320 names[arity + i] = zero.newIndex(arity + i); 321 } 322 return names; 323 } 324 325 private static int fixResult(int result, Name[] names) { 326 if (result == LAST_RESULT) 327 result = names.length - 1; // might still be void 328 if (result >= 0 && names[result].type == V_TYPE) 329 result = VOID_RESULT; 330 return result; 331 } 332 333 private static String fixDebugName(String debugName) { 334 if (DEBUG_NAME_COUNTERS != null) { 335 int under = debugName.indexOf('_'); 336 int length = debugName.length(); 337 if (under < 0) under = length; 338 String debugNameStem = debugName.substring(0, under); 339 Integer ctr; 340 synchronized (DEBUG_NAME_COUNTERS) { 341 ctr = DEBUG_NAME_COUNTERS.get(debugNameStem); 342 if (ctr == null) ctr = 0; 343 DEBUG_NAME_COUNTERS.put(debugNameStem, ctr+1); 344 } 345 StringBuilder buf = new StringBuilder(debugNameStem); 346 buf.append('_'); 347 int leadingZero = buf.length(); 348 buf.append((int) ctr); 349 for (int i = buf.length() - leadingZero; i < 3; i++) 350 buf.insert(leadingZero, '0'); 351 if (under < length) { 352 ++under; // skip "_" 353 while (under < length && Character.isDigit(debugName.charAt(under))) { 354 ++under; 355 } 356 if (under < length && debugName.charAt(under) == '_') ++under; 357 if (under < length) 358 buf.append('_').append(debugName, under, length); 359 } 360 return buf.toString(); 361 } 362 return debugName; 363 } 364 365 private static boolean namesOK(int arity, Name[] names) { 366 for (int i = 0; i < names.length; i++) { 367 Name n = names[i]; 368 assert(n != null) : "n is null"; 369 if (i < arity) 370 assert( n.isParam()) : n + " is not param at " + i; 371 else 372 assert(!n.isParam()) : n + " is param at " + i; 373 } 374 return true; 375 } 376 377 LambdaForm customize(MethodHandle mh) { 378 LambdaForm customForm = new LambdaForm(debugName, arity, names, result, forceInline, mh); 379 if (COMPILE_THRESHOLD > 0 && isCompiled) { 380 // If shared LambdaForm has been compiled, compile customized version as well. 381 customForm.compileToBytecode(); 382 } 383 return customForm; 384 } 385 386 LambdaForm uncustomize() { 387 if (customized == null) { 388 return this; 389 } 390 LambdaForm uncustomizedForm = new LambdaForm(debugName, arity, names, result, forceInline, null); 391 if (COMPILE_THRESHOLD > 0 && isCompiled) { 392 // If customized LambdaForm has been compiled, compile uncustomized version as well. 393 uncustomizedForm.compileToBytecode(); 394 } 395 return uncustomizedForm; 396 } 397 398 /** Renumber and/or replace params so that they are interned and canonically numbered. 399 * @return maximum argument list length among the names (since we have to pass over them anyway) 400 */ 401 private int normalize() { 402 Name[] oldNames = null; 403 int maxOutArity = 0; 404 int changesStart = 0; 405 for (int i = 0; i < names.length; i++) { 406 Name n = names[i]; 407 if (!n.initIndex(i)) { 408 if (oldNames == null) { 409 oldNames = names.clone(); 410 changesStart = i; 411 } 412 names[i] = n.cloneWithIndex(i); 413 } 414 if (n.arguments != null && maxOutArity < n.arguments.length) 415 maxOutArity = n.arguments.length; 416 } 417 if (oldNames != null) { 418 int startFixing = arity; 419 if (startFixing <= changesStart) 420 startFixing = changesStart+1; 421 for (int i = startFixing; i < names.length; i++) { 422 Name fixed = names[i].replaceNames(oldNames, names, changesStart, i); 423 names[i] = fixed.newIndex(i); 424 } 425 } 426 assert(nameRefsAreLegal()); 427 int maxInterned = Math.min(arity, INTERNED_ARGUMENT_LIMIT); 428 boolean needIntern = false; 429 for (int i = 0; i < maxInterned; i++) { 430 Name n = names[i], n2 = internArgument(n); 431 if (n != n2) { 432 names[i] = n2; 433 needIntern = true; 434 } 435 } 436 if (needIntern) { 437 for (int i = arity; i < names.length; i++) { 438 names[i].internArguments(); 439 } 440 } 441 assert(nameRefsAreLegal()); 442 return maxOutArity; 443 } 444 445 /** 446 * Check that all embedded Name references are localizable to this lambda, 447 * and are properly ordered after their corresponding definitions. 448 * <p> 449 * Note that a Name can be local to multiple lambdas, as long as 450 * it possesses the same index in each use site. 451 * This allows Name references to be freely reused to construct 452 * fresh lambdas, without confusion. 453 */ 454 boolean nameRefsAreLegal() { 455 assert(arity >= 0 && arity <= names.length); 456 assert(result >= -1 && result < names.length); 457 // Do all names possess an index consistent with their local definition order? 458 for (int i = 0; i < arity; i++) { 459 Name n = names[i]; 460 assert(n.index() == i) : Arrays.asList(n.index(), i); 461 assert(n.isParam()); 462 } 463 // Also, do all local name references 464 for (int i = arity; i < names.length; i++) { 465 Name n = names[i]; 466 assert(n.index() == i); 467 for (Object arg : n.arguments) { 468 if (arg instanceof Name) { 469 Name n2 = (Name) arg; 470 int i2 = n2.index; 471 assert(0 <= i2 && i2 < names.length) : n.debugString() + ": 0 <= i2 && i2 < names.length: 0 <= " + i2 + " < " + names.length; 472 assert(names[i2] == n2) : Arrays.asList("-1-", i, "-2-", n.debugString(), "-3-", i2, "-4-", n2.debugString(), "-5-", names[i2].debugString(), "-6-", this); 473 assert(i2 < i); // ref must come after def! 474 } 475 } 476 } 477 return true; 478 } 479 480 /** Invoke this form on the given arguments. */ 481 // final Object invoke(Object... args) throws Throwable { 482 // // NYI: fit this into the fast path? 483 // return interpretWithArguments(args); 484 // } 485 486 /** Report the return type. */ 487 BasicType returnType() { 488 if (result < 0) return V_TYPE; 489 Name n = names[result]; 490 return n.type; 491 } 492 493 /** Report the N-th argument type. */ 494 BasicType parameterType(int n) { 495 return parameter(n).type; 496 } 497 498 /** Report the N-th argument name. */ 499 Name parameter(int n) { 500 assert(n < arity); 501 Name param = names[n]; 502 assert(param.isParam()); 503 return param; 504 } 505 506 /** Report the N-th argument type constraint. */ 507 Object parameterConstraint(int n) { 508 return parameter(n).constraint; 509 } 510 511 /** Report the arity. */ 512 int arity() { 513 return arity; 514 } 515 516 /** Report the number of expressions (non-parameter names). */ 517 int expressionCount() { 518 return names.length - arity; 519 } 520 521 /** Return the method type corresponding to my basic type signature. */ 522 MethodType methodType() { 523 return signatureType(basicTypeSignature()); 524 } 525 /** Return ABC_Z, where the ABC are parameter type characters, and Z is the return type character. */ 526 final String basicTypeSignature() { 527 StringBuilder buf = new StringBuilder(arity() + 3); 528 for (int i = 0, a = arity(); i < a; i++) 529 buf.append(parameterType(i).basicTypeChar()); 530 return buf.append('_').append(returnType().basicTypeChar()).toString(); 531 } 532 static int signatureArity(String sig) { 533 assert(isValidSignature(sig)); 534 return sig.indexOf('_'); 535 } 536 static BasicType signatureReturn(String sig) { 537 return basicType(sig.charAt(signatureArity(sig) + 1)); 538 } 539 static boolean isValidSignature(String sig) { 540 int arity = sig.indexOf('_'); 541 if (arity < 0) return false; // must be of the form *_* 542 int siglen = sig.length(); 543 if (siglen != arity + 2) return false; // *_X 544 for (int i = 0; i < siglen; i++) { 545 if (i == arity) continue; // skip '_' 546 char c = sig.charAt(i); 547 if (c == 'V') 548 return (i == siglen - 1 && arity == siglen - 2); 549 if (!isArgBasicTypeChar(c)) return false; // must be [LIJFD] 550 } 551 return true; // [LIJFD]*_[LIJFDV] 552 } 553 static MethodType signatureType(String sig) { 554 Class<?>[] ptypes = new Class<?>[signatureArity(sig)]; 555 for (int i = 0; i < ptypes.length; i++) 556 ptypes[i] = basicType(sig.charAt(i)).btClass; 557 Class<?> rtype = signatureReturn(sig).btClass; 558 return MethodType.methodType(rtype, ptypes); 559 } 560 561 /* 562 * Code generation issues: 563 * 564 * Compiled LFs should be reusable in general. 565 * The biggest issue is how to decide when to pull a name into 566 * the bytecode, versus loading a reified form from the MH data. 567 * 568 * For example, an asType wrapper may require execution of a cast 569 * after a call to a MH. The target type of the cast can be placed 570 * as a constant in the LF itself. This will force the cast type 571 * to be compiled into the bytecodes and native code for the MH. 572 * Or, the target type of the cast can be erased in the LF, and 573 * loaded from the MH data. (Later on, if the MH as a whole is 574 * inlined, the data will flow into the inlined instance of the LF, 575 * as a constant, and the end result will be an optimal cast.) 576 * 577 * This erasure of cast types can be done with any use of 578 * reference types. It can also be done with whole method 579 * handles. Erasing a method handle might leave behind 580 * LF code that executes correctly for any MH of a given 581 * type, and load the required MH from the enclosing MH's data. 582 * Or, the erasure might even erase the expected MT. 583 * 584 * Also, for direct MHs, the MemberName of the target 585 * could be erased, and loaded from the containing direct MH. 586 * As a simple case, a LF for all int-valued non-static 587 * field getters would perform a cast on its input argument 588 * (to non-constant base type derived from the MemberName) 589 * and load an integer value from the input object 590 * (at a non-constant offset also derived from the MemberName). 591 * Such MN-erased LFs would be inlinable back to optimized 592 * code, whenever a constant enclosing DMH is available 593 * to supply a constant MN from its data. 594 * 595 * The main problem here is to keep LFs reasonably generic, 596 * while ensuring that hot spots will inline good instances. 597 * "Reasonably generic" means that we don't end up with 598 * repeated versions of bytecode or machine code that do 599 * not differ in their optimized form. Repeated versions 600 * of machine would have the undesirable overheads of 601 * (a) redundant compilation work and (b) extra I$ pressure. 602 * To control repeated versions, we need to be ready to 603 * erase details from LFs and move them into MH data, 604 * whevener those details are not relevant to significant 605 * optimization. "Significant" means optimization of 606 * code that is actually hot. 607 * 608 * Achieving this may require dynamic splitting of MHs, by replacing 609 * a generic LF with a more specialized one, on the same MH, 610 * if (a) the MH is frequently executed and (b) the MH cannot 611 * be inlined into a containing caller, such as an invokedynamic. 612 * 613 * Compiled LFs that are no longer used should be GC-able. 614 * If they contain non-BCP references, they should be properly 615 * interlinked with the class loader(s) that their embedded types 616 * depend on. This probably means that reusable compiled LFs 617 * will be tabulated (indexed) on relevant class loaders, 618 * or else that the tables that cache them will have weak links. 619 */ 620 621 /** 622 * Make this LF directly executable, as part of a MethodHandle. 623 * Invariant: Every MH which is invoked must prepare its LF 624 * before invocation. 625 * (In principle, the JVM could do this very lazily, 626 * as a sort of pre-invocation linkage step.) 627 */ 628 public void prepare() { 629 if (COMPILE_THRESHOLD == 0) { 630 compileToBytecode(); 631 } 632 if (this.vmentry != null) { 633 // already prepared (e.g., a primitive DMH invoker form) 634 return; 635 } 636 LambdaForm prep = getPreparedForm(basicTypeSignature()); 637 this.vmentry = prep.vmentry; 638 // TO DO: Maybe add invokeGeneric, invokeWithArguments 639 } 640 641 /** Generate optimizable bytecode for this form. */ 642 MemberName compileToBytecode() { 643 MethodType invokerType = methodType(); 644 assert(vmentry == null || vmentry.getMethodType().basicType().equals(invokerType)); 645 if (vmentry != null && isCompiled) { 646 return vmentry; // already compiled somehow 647 } 648 try { 649 vmentry = InvokerBytecodeGenerator.generateCustomizedCode(this, invokerType); 650 if (TRACE_INTERPRETER) 651 traceInterpreter("compileToBytecode", this); 652 isCompiled = true; 653 return vmentry; 654 } catch (Error | Exception ex) { 655 throw newInternalError(this.toString(), ex); 656 } 657 } 658 659 private static void computeInitialPreparedForms() { 660 // Find all predefined invokers and associate them with canonical empty lambda forms. 661 for (MemberName m : MemberName.getFactory().getMethods(LambdaForm.class, false, null, null, null)) { 662 if (!m.isStatic() || !m.isPackage()) continue; 663 MethodType mt = m.getMethodType(); 664 if (mt.parameterCount() > 0 && 665 mt.parameterType(0) == MethodHandle.class && 666 m.getName().startsWith("interpret_")) { 667 String sig = basicTypeSignature(mt); 668 assert(m.getName().equals("interpret" + sig.substring(sig.indexOf('_')))); 669 LambdaForm form = new LambdaForm(sig); 670 form.vmentry = m; 671 form = mt.form().setCachedLambdaForm(MethodTypeForm.LF_INTERPRET, form); 672 } 673 } 674 } 675 676 // Set this false to disable use of the interpret_L methods defined in this file. 677 private static final boolean USE_PREDEFINED_INTERPRET_METHODS = true; 678 679 // The following are predefined exact invokers. The system must build 680 // a separate invoker for each distinct signature. 681 static Object interpret_L(MethodHandle mh) throws Throwable { 682 Object[] av = {mh}; 683 String sig = null; 684 assert(argumentTypesMatch(sig = "L_L", av)); 685 Object res = mh.form.interpretWithArguments(av); 686 assert(returnTypesMatch(sig, av, res)); 687 return res; 688 } 689 static Object interpret_L(MethodHandle mh, Object x1) throws Throwable { 690 Object[] av = {mh, x1}; 691 String sig = null; 692 assert(argumentTypesMatch(sig = "LL_L", av)); 693 Object res = mh.form.interpretWithArguments(av); 694 assert(returnTypesMatch(sig, av, res)); 695 return res; 696 } 697 static Object interpret_L(MethodHandle mh, Object x1, Object x2) throws Throwable { 698 Object[] av = {mh, x1, x2}; 699 String sig = null; 700 assert(argumentTypesMatch(sig = "LLL_L", av)); 701 Object res = mh.form.interpretWithArguments(av); 702 assert(returnTypesMatch(sig, av, res)); 703 return res; 704 } 705 private static LambdaForm getPreparedForm(String sig) { 706 MethodType mtype = signatureType(sig); 707 LambdaForm prep = mtype.form().cachedLambdaForm(MethodTypeForm.LF_INTERPRET); 708 if (prep != null) return prep; 709 assert(isValidSignature(sig)); 710 prep = new LambdaForm(sig); 711 prep.vmentry = InvokerBytecodeGenerator.generateLambdaFormInterpreterEntryPoint(sig); 712 return mtype.form().setCachedLambdaForm(MethodTypeForm.LF_INTERPRET, prep); 713 } 714 715 // The next few routines are called only from assert expressions 716 // They verify that the built-in invokers process the correct raw data types. 717 private static boolean argumentTypesMatch(String sig, Object[] av) { 718 int arity = signatureArity(sig); 719 assert(av.length == arity) : "av.length == arity: av.length=" + av.length + ", arity=" + arity; 720 assert(av[0] instanceof MethodHandle) : "av[0] not instace of MethodHandle: " + av[0]; 721 MethodHandle mh = (MethodHandle) av[0]; 722 MethodType mt = mh.type(); 723 assert(mt.parameterCount() == arity-1); 724 for (int i = 0; i < av.length; i++) { 725 Class<?> pt = (i == 0 ? MethodHandle.class : mt.parameterType(i-1)); 726 assert(valueMatches(basicType(sig.charAt(i)), pt, av[i])); 727 } 728 return true; 729 } 730 private static boolean valueMatches(BasicType tc, Class<?> type, Object x) { 731 // The following line is needed because (...)void method handles can use non-void invokers 732 if (type == void.class) tc = V_TYPE; // can drop any kind of value 733 assert tc == basicType(type) : tc + " == basicType(" + type + ")=" + basicType(type); 734 switch (tc) { 735 case I_TYPE: assert checkInt(type, x) : "checkInt(" + type + "," + x +")"; break; 736 case J_TYPE: assert x instanceof Long : "instanceof Long: " + x; break; 737 case F_TYPE: assert x instanceof Float : "instanceof Float: " + x; break; 738 case D_TYPE: assert x instanceof Double : "instanceof Double: " + x; break; 739 case L_TYPE: assert checkRef(type, x) : "checkRef(" + type + "," + x + ")"; break; 740 case V_TYPE: break; // allow anything here; will be dropped 741 default: assert(false); 742 } 743 return true; 744 } 745 private static boolean returnTypesMatch(String sig, Object[] av, Object res) { 746 MethodHandle mh = (MethodHandle) av[0]; 747 return valueMatches(signatureReturn(sig), mh.type().returnType(), res); 748 } 749 private static boolean checkInt(Class<?> type, Object x) { 750 assert(x instanceof Integer); 751 if (type == int.class) return true; 752 Wrapper w = Wrapper.forBasicType(type); 753 assert(w.isSubwordOrInt()); 754 Object x1 = Wrapper.INT.wrap(w.wrap(x)); 755 return x.equals(x1); 756 } 757 private static boolean checkRef(Class<?> type, Object x) { 758 assert(!type.isPrimitive()); 759 if (x == null) return true; 760 if (type.isInterface()) return true; 761 return type.isInstance(x); 762 } 763 764 /** If the invocation count hits the threshold we spin bytecodes and call that subsequently. */ 765 private static final int COMPILE_THRESHOLD; 766 static { 767 COMPILE_THRESHOLD = Math.max(-1, MethodHandleStatics.COMPILE_THRESHOLD); 768 } 769 private int invocationCounter = 0; 770 771 @Hidden 772 @DontInline 773 /** Interpretively invoke this form on the given arguments. */ 774 Object interpretWithArguments(Object... argumentValues) throws Throwable { 775 if (TRACE_INTERPRETER) 776 return interpretWithArgumentsTracing(argumentValues); 777 checkInvocationCounter(); 778 assert(arityCheck(argumentValues)); 779 Object[] values = Arrays.copyOf(argumentValues, names.length); 780 for (int i = argumentValues.length; i < values.length; i++) { 781 values[i] = interpretName(names[i], values); 782 } 783 Object rv = (result < 0) ? null : values[result]; 784 assert(resultCheck(argumentValues, rv)); 785 return rv; 786 } 787 788 @Hidden 789 @DontInline 790 /** Evaluate a single Name within this form, applying its function to its arguments. */ 791 Object interpretName(Name name, Object[] values) throws Throwable { 792 if (TRACE_INTERPRETER) 793 traceInterpreter("| interpretName", name.debugString(), (Object[]) null); 794 Object[] arguments = Arrays.copyOf(name.arguments, name.arguments.length, Object[].class); 795 for (int i = 0; i < arguments.length; i++) { 796 Object a = arguments[i]; 797 if (a instanceof Name) { 798 int i2 = ((Name)a).index(); 799 assert(names[i2] == a); 800 a = values[i2]; 801 arguments[i] = a; 802 } 803 } 804 return name.function.invokeWithArguments(arguments); 805 } 806 807 private void checkInvocationCounter() { 808 if (COMPILE_THRESHOLD != 0 && 809 invocationCounter < COMPILE_THRESHOLD) { 810 invocationCounter++; // benign race 811 if (invocationCounter >= COMPILE_THRESHOLD) { 812 // Replace vmentry with a bytecode version of this LF. 813 compileToBytecode(); 814 } 815 } 816 } 817 Object interpretWithArgumentsTracing(Object... argumentValues) throws Throwable { 818 traceInterpreter("[ interpretWithArguments", this, argumentValues); 819 if (invocationCounter < COMPILE_THRESHOLD) { 820 int ctr = invocationCounter++; // benign race 821 traceInterpreter("| invocationCounter", ctr); 822 if (invocationCounter >= COMPILE_THRESHOLD) { 823 compileToBytecode(); 824 } 825 } 826 Object rval; 827 try { 828 assert(arityCheck(argumentValues)); 829 Object[] values = Arrays.copyOf(argumentValues, names.length); 830 for (int i = argumentValues.length; i < values.length; i++) { 831 values[i] = interpretName(names[i], values); 832 } 833 rval = (result < 0) ? null : values[result]; 834 } catch (Throwable ex) { 835 traceInterpreter("] throw =>", ex); 836 throw ex; 837 } 838 traceInterpreter("] return =>", rval); 839 return rval; 840 } 841 842 static void traceInterpreter(String event, Object obj, Object... args) { 843 if (TRACE_INTERPRETER) { 844 System.out.println("LFI: "+event+" "+(obj != null ? obj : "")+(args != null && args.length != 0 ? Arrays.asList(args) : "")); 845 } 846 } 847 static void traceInterpreter(String event, Object obj) { 848 traceInterpreter(event, obj, (Object[])null); 849 } 850 private boolean arityCheck(Object[] argumentValues) { 851 assert(argumentValues.length == arity) : arity+"!="+Arrays.asList(argumentValues)+".length"; 852 // also check that the leading (receiver) argument is somehow bound to this LF: 853 assert(argumentValues[0] instanceof MethodHandle) : "not MH: " + argumentValues[0]; 854 MethodHandle mh = (MethodHandle) argumentValues[0]; 855 assert(mh.internalForm() == this); 856 // note: argument #0 could also be an interface wrapper, in the future 857 argumentTypesMatch(basicTypeSignature(), argumentValues); 858 return true; 859 } 860 private boolean resultCheck(Object[] argumentValues, Object result) { 861 MethodHandle mh = (MethodHandle) argumentValues[0]; 862 MethodType mt = mh.type(); 863 assert(valueMatches(returnType(), mt.returnType(), result)); 864 return true; 865 } 866 867 private boolean isEmpty() { 868 if (result < 0) 869 return (names.length == arity); 870 else if (result == arity && names.length == arity + 1) 871 return names[arity].isConstantZero(); 872 else 873 return false; 874 } 875 876 public String toString() { 877 StringBuilder buf = new StringBuilder(debugName+"=Lambda("); 878 for (int i = 0; i < names.length; i++) { 879 if (i == arity) buf.append(")=>{"); 880 Name n = names[i]; 881 if (i >= arity) buf.append("\n "); 882 buf.append(n.paramString()); 883 if (i < arity) { 884 if (i+1 < arity) buf.append(","); 885 continue; 886 } 887 buf.append("=").append(n.exprString()); 888 buf.append(";"); 889 } 890 if (arity == names.length) buf.append(")=>{"); 891 buf.append(result < 0 ? "void" : names[result]).append("}"); 892 if (TRACE_INTERPRETER) { 893 // Extra verbosity: 894 buf.append(":").append(basicTypeSignature()); 895 buf.append("/").append(vmentry); 896 } 897 return buf.toString(); 898 } 899 900 @Override 901 public boolean equals(Object obj) { 902 return obj instanceof LambdaForm && equals((LambdaForm)obj); 903 } 904 public boolean equals(LambdaForm that) { 905 if (this.result != that.result) return false; 906 return Arrays.equals(this.names, that.names); 907 } 908 public int hashCode() { 909 return result + 31 * Arrays.hashCode(names); 910 } 911 LambdaFormEditor editor() { 912 return LambdaFormEditor.lambdaFormEditor(this); 913 } 914 915 boolean contains(Name name) { 916 int pos = name.index(); 917 if (pos >= 0) { 918 return pos < names.length && name.equals(names[pos]); 919 } 920 for (int i = arity; i < names.length; i++) { 921 if (name.equals(names[i])) 922 return true; 923 } 924 return false; 925 } 926 927 LambdaForm addArguments(int pos, BasicType... types) { 928 // names array has MH in slot 0; skip it. 929 int argpos = pos + 1; 930 assert(argpos <= arity); 931 int length = names.length; 932 int inTypes = types.length; 933 Name[] names2 = Arrays.copyOf(names, length + inTypes); 934 int arity2 = arity + inTypes; 935 int result2 = result; 936 if (result2 >= argpos) 937 result2 += inTypes; 938 // Note: The LF constructor will rename names2[argpos...]. 939 // Make space for new arguments (shift temporaries). 940 System.arraycopy(names, argpos, names2, argpos + inTypes, length - argpos); 941 for (int i = 0; i < inTypes; i++) { 942 names2[argpos + i] = new Name(types[i]); 943 } 944 return new LambdaForm(debugName, arity2, names2, result2); 945 } 946 947 LambdaForm addArguments(int pos, List<Class<?>> types) { 948 return addArguments(pos, basicTypes(types)); 949 } 950 951 LambdaForm permuteArguments(int skip, int[] reorder, BasicType[] types) { 952 // Note: When inArg = reorder[outArg], outArg is fed by a copy of inArg. 953 // The types are the types of the new (incoming) arguments. 954 int length = names.length; 955 int inTypes = types.length; 956 int outArgs = reorder.length; 957 assert(skip+outArgs == arity); 958 assert(permutedTypesMatch(reorder, types, names, skip)); 959 int pos = 0; 960 // skip trivial first part of reordering: 961 while (pos < outArgs && reorder[pos] == pos) pos += 1; 962 Name[] names2 = new Name[length - outArgs + inTypes]; 963 System.arraycopy(names, 0, names2, 0, skip+pos); 964 // copy the body: 965 int bodyLength = length - arity; 966 System.arraycopy(names, skip+outArgs, names2, skip+inTypes, bodyLength); 967 int arity2 = names2.length - bodyLength; 968 int result2 = result; 969 if (result2 >= 0) { 970 if (result2 < skip+outArgs) { 971 // return the corresponding inArg 972 result2 = reorder[result2-skip]; 973 } else { 974 result2 = result2 - outArgs + inTypes; 975 } 976 } 977 // rework names in the body: 978 for (int j = pos; j < outArgs; j++) { 979 Name n = names[skip+j]; 980 int i = reorder[j]; 981 // replace names[skip+j] by names2[skip+i] 982 Name n2 = names2[skip+i]; 983 if (n2 == null) 984 names2[skip+i] = n2 = new Name(types[i]); 985 else 986 assert(n2.type == types[i]); 987 for (int k = arity2; k < names2.length; k++) { 988 names2[k] = names2[k].replaceName(n, n2); 989 } 990 } 991 // some names are unused, but must be filled in 992 for (int i = skip+pos; i < arity2; i++) { 993 if (names2[i] == null) 994 names2[i] = argument(i, types[i - skip]); 995 } 996 for (int j = arity; j < names.length; j++) { 997 int i = j - arity + arity2; 998 // replace names2[i] by names[j] 999 Name n = names[j]; 1000 Name n2 = names2[i]; 1001 if (n != n2) { 1002 for (int k = i+1; k < names2.length; k++) { 1003 names2[k] = names2[k].replaceName(n, n2); 1004 } 1005 } 1006 } 1007 return new LambdaForm(debugName, arity2, names2, result2); 1008 } 1009 1010 static boolean permutedTypesMatch(int[] reorder, BasicType[] types, Name[] names, int skip) { 1011 int inTypes = types.length; 1012 int outArgs = reorder.length; 1013 for (int i = 0; i < outArgs; i++) { 1014 assert(names[skip+i].isParam()); 1015 assert(names[skip+i].type == types[reorder[i]]); 1016 } 1017 return true; 1018 } 1019 1020 static class NamedFunction { 1021 final MemberName member; 1022 @Stable MethodHandle resolvedHandle; 1023 @Stable MethodHandle invoker; 1024 1025 NamedFunction(MethodHandle resolvedHandle) { 1026 this(resolvedHandle.internalMemberName(), resolvedHandle); 1027 } 1028 NamedFunction(MemberName member, MethodHandle resolvedHandle) { 1029 this.member = member; 1030 this.resolvedHandle = resolvedHandle; 1031 // The following assert is almost always correct, but will fail for corner cases, such as PrivateInvokeTest. 1032 //assert(!isInvokeBasic()); 1033 } 1034 NamedFunction(MethodType basicInvokerType) { 1035 assert(basicInvokerType == basicInvokerType.basicType()) : basicInvokerType; 1036 if (basicInvokerType.parameterSlotCount() < MethodType.MAX_MH_INVOKER_ARITY) { 1037 this.resolvedHandle = basicInvokerType.invokers().basicInvoker(); 1038 this.member = resolvedHandle.internalMemberName(); 1039 } else { 1040 // necessary to pass BigArityTest 1041 this.member = Invokers.invokeBasicMethod(basicInvokerType); 1042 } 1043 assert(isInvokeBasic()); 1044 } 1045 1046 private boolean isInvokeBasic() { 1047 return member != null && 1048 member.isMethodHandleInvoke() && 1049 "invokeBasic".equals(member.getName()); 1050 } 1051 1052 // The next 3 constructors are used to break circular dependencies on MH.invokeStatic, etc. 1053 // Any LambdaForm containing such a member is not interpretable. 1054 // This is OK, since all such LFs are prepared with special primitive vmentry points. 1055 // And even without the resolvedHandle, the name can still be compiled and optimized. 1056 NamedFunction(Method method) { 1057 this(new MemberName(method)); 1058 } 1059 NamedFunction(Field field) { 1060 this(new MemberName(field)); 1061 } 1062 NamedFunction(MemberName member) { 1063 this.member = member; 1064 this.resolvedHandle = null; 1065 } 1066 1067 MethodHandle resolvedHandle() { 1068 if (resolvedHandle == null) resolve(); 1069 return resolvedHandle; 1070 } 1071 1072 void resolve() { 1073 resolvedHandle = DirectMethodHandle.make(member); 1074 } 1075 1076 @Override 1077 public boolean equals(Object other) { 1078 if (this == other) return true; 1079 if (other == null) return false; 1080 if (!(other instanceof NamedFunction)) return false; 1081 NamedFunction that = (NamedFunction) other; 1082 return this.member != null && this.member.equals(that.member); 1083 } 1084 1085 @Override 1086 public int hashCode() { 1087 if (member != null) 1088 return member.hashCode(); 1089 return super.hashCode(); 1090 } 1091 1092 // Put the predefined NamedFunction invokers into the table. 1093 static void initializeInvokers() { 1094 for (MemberName m : MemberName.getFactory().getMethods(NamedFunction.class, false, null, null, null)) { 1095 if (!m.isStatic() || !m.isPackage()) continue; 1096 MethodType type = m.getMethodType(); 1097 if (type.equals(INVOKER_METHOD_TYPE) && 1098 m.getName().startsWith("invoke_")) { 1099 String sig = m.getName().substring("invoke_".length()); 1100 int arity = LambdaForm.signatureArity(sig); 1101 MethodType srcType = MethodType.genericMethodType(arity); 1102 if (LambdaForm.signatureReturn(sig) == V_TYPE) 1103 srcType = srcType.changeReturnType(void.class); 1104 MethodTypeForm typeForm = srcType.form(); 1105 typeForm.setCachedMethodHandle(MethodTypeForm.MH_NF_INV, DirectMethodHandle.make(m)); 1106 } 1107 } 1108 } 1109 1110 // The following are predefined NamedFunction invokers. The system must build 1111 // a separate invoker for each distinct signature. 1112 /** void return type invokers. */ 1113 @Hidden 1114 static Object invoke__V(MethodHandle mh, Object[] a) throws Throwable { 1115 assert(arityCheck(0, void.class, mh, a)); 1116 mh.invokeBasic(); 1117 return null; 1118 } 1119 @Hidden 1120 static Object invoke_L_V(MethodHandle mh, Object[] a) throws Throwable { 1121 assert(arityCheck(1, void.class, mh, a)); 1122 mh.invokeBasic(a[0]); 1123 return null; 1124 } 1125 @Hidden 1126 static Object invoke_LL_V(MethodHandle mh, Object[] a) throws Throwable { 1127 assert(arityCheck(2, void.class, mh, a)); 1128 mh.invokeBasic(a[0], a[1]); 1129 return null; 1130 } 1131 @Hidden 1132 static Object invoke_LLL_V(MethodHandle mh, Object[] a) throws Throwable { 1133 assert(arityCheck(3, void.class, mh, a)); 1134 mh.invokeBasic(a[0], a[1], a[2]); 1135 return null; 1136 } 1137 @Hidden 1138 static Object invoke_LLLL_V(MethodHandle mh, Object[] a) throws Throwable { 1139 assert(arityCheck(4, void.class, mh, a)); 1140 mh.invokeBasic(a[0], a[1], a[2], a[3]); 1141 return null; 1142 } 1143 @Hidden 1144 static Object invoke_LLLLL_V(MethodHandle mh, Object[] a) throws Throwable { 1145 assert(arityCheck(5, void.class, mh, a)); 1146 mh.invokeBasic(a[0], a[1], a[2], a[3], a[4]); 1147 return null; 1148 } 1149 /** Object return type invokers. */ 1150 @Hidden 1151 static Object invoke__L(MethodHandle mh, Object[] a) throws Throwable { 1152 assert(arityCheck(0, mh, a)); 1153 return mh.invokeBasic(); 1154 } 1155 @Hidden 1156 static Object invoke_L_L(MethodHandle mh, Object[] a) throws Throwable { 1157 assert(arityCheck(1, mh, a)); 1158 return mh.invokeBasic(a[0]); 1159 } 1160 @Hidden 1161 static Object invoke_LL_L(MethodHandle mh, Object[] a) throws Throwable { 1162 assert(arityCheck(2, mh, a)); 1163 return mh.invokeBasic(a[0], a[1]); 1164 } 1165 @Hidden 1166 static Object invoke_LLL_L(MethodHandle mh, Object[] a) throws Throwable { 1167 assert(arityCheck(3, mh, a)); 1168 return mh.invokeBasic(a[0], a[1], a[2]); 1169 } 1170 @Hidden 1171 static Object invoke_LLLL_L(MethodHandle mh, Object[] a) throws Throwable { 1172 assert(arityCheck(4, mh, a)); 1173 return mh.invokeBasic(a[0], a[1], a[2], a[3]); 1174 } 1175 @Hidden 1176 static Object invoke_LLLLL_L(MethodHandle mh, Object[] a) throws Throwable { 1177 assert(arityCheck(5, mh, a)); 1178 return mh.invokeBasic(a[0], a[1], a[2], a[3], a[4]); 1179 } 1180 private static boolean arityCheck(int arity, MethodHandle mh, Object[] a) { 1181 return arityCheck(arity, Object.class, mh, a); 1182 } 1183 private static boolean arityCheck(int arity, Class<?> rtype, MethodHandle mh, Object[] a) { 1184 assert(a.length == arity) 1185 : Arrays.asList(a.length, arity); 1186 assert(mh.type().basicType() == MethodType.genericMethodType(arity).changeReturnType(rtype)) 1187 : Arrays.asList(mh, rtype, arity); 1188 MemberName member = mh.internalMemberName(); 1189 if (member != null && member.getName().equals("invokeBasic") && member.isMethodHandleInvoke()) { 1190 assert(arity > 0); 1191 assert(a[0] instanceof MethodHandle); 1192 MethodHandle mh2 = (MethodHandle) a[0]; 1193 assert(mh2.type().basicType() == MethodType.genericMethodType(arity-1).changeReturnType(rtype)) 1194 : Arrays.asList(member, mh2, rtype, arity); 1195 } 1196 return true; 1197 } 1198 1199 static final MethodType INVOKER_METHOD_TYPE = 1200 MethodType.methodType(Object.class, MethodHandle.class, Object[].class); 1201 1202 private static MethodHandle computeInvoker(MethodTypeForm typeForm) { 1203 typeForm = typeForm.basicType().form(); // normalize to basic type 1204 MethodHandle mh = typeForm.cachedMethodHandle(MethodTypeForm.MH_NF_INV); 1205 if (mh != null) return mh; 1206 MemberName invoker = InvokerBytecodeGenerator.generateNamedFunctionInvoker(typeForm); // this could take a while 1207 mh = DirectMethodHandle.make(invoker); 1208 MethodHandle mh2 = typeForm.cachedMethodHandle(MethodTypeForm.MH_NF_INV); 1209 if (mh2 != null) return mh2; // benign race 1210 if (!mh.type().equals(INVOKER_METHOD_TYPE)) 1211 throw newInternalError(mh.debugString()); 1212 return typeForm.setCachedMethodHandle(MethodTypeForm.MH_NF_INV, mh); 1213 } 1214 1215 @Hidden 1216 Object invokeWithArguments(Object... arguments) throws Throwable { 1217 // If we have a cached invoker, call it right away. 1218 // NOTE: The invoker always returns a reference value. 1219 if (TRACE_INTERPRETER) return invokeWithArgumentsTracing(arguments); 1220 assert(checkArgumentTypes(arguments, methodType())); 1221 return invoker().invokeBasic(resolvedHandle(), arguments); 1222 } 1223 1224 @Hidden 1225 Object invokeWithArgumentsTracing(Object[] arguments) throws Throwable { 1226 Object rval; 1227 try { 1228 traceInterpreter("[ call", this, arguments); 1229 if (invoker == null) { 1230 traceInterpreter("| getInvoker", this); 1231 invoker(); 1232 } 1233 if (resolvedHandle == null) { 1234 traceInterpreter("| resolve", this); 1235 resolvedHandle(); 1236 } 1237 assert(checkArgumentTypes(arguments, methodType())); 1238 rval = invoker().invokeBasic(resolvedHandle(), arguments); 1239 } catch (Throwable ex) { 1240 traceInterpreter("] throw =>", ex); 1241 throw ex; 1242 } 1243 traceInterpreter("] return =>", rval); 1244 return rval; 1245 } 1246 1247 private MethodHandle invoker() { 1248 if (invoker != null) return invoker; 1249 // Get an invoker and cache it. 1250 return invoker = computeInvoker(methodType().form()); 1251 } 1252 1253 private static boolean checkArgumentTypes(Object[] arguments, MethodType methodType) { 1254 if (true) return true; // FIXME 1255 MethodType dstType = methodType.form().erasedType(); 1256 MethodType srcType = dstType.basicType().wrap(); 1257 Class<?>[] ptypes = new Class<?>[arguments.length]; 1258 for (int i = 0; i < arguments.length; i++) { 1259 Object arg = arguments[i]; 1260 Class<?> ptype = arg == null ? Object.class : arg.getClass(); 1261 // If the dest. type is a primitive we keep the 1262 // argument type. 1263 ptypes[i] = dstType.parameterType(i).isPrimitive() ? ptype : Object.class; 1264 } 1265 MethodType argType = MethodType.methodType(srcType.returnType(), ptypes).wrap(); 1266 assert(argType.isConvertibleTo(srcType)) : "wrong argument types: cannot convert " + argType + " to " + srcType; 1267 return true; 1268 } 1269 1270 MethodType methodType() { 1271 if (resolvedHandle != null) 1272 return resolvedHandle.type(); 1273 else 1274 // only for certain internal LFs during bootstrapping 1275 return member.getInvocationType(); 1276 } 1277 1278 MemberName member() { 1279 assert(assertMemberIsConsistent()); 1280 return member; 1281 } 1282 1283 // Called only from assert. 1284 private boolean assertMemberIsConsistent() { 1285 if (resolvedHandle instanceof DirectMethodHandle) { 1286 MemberName m = resolvedHandle.internalMemberName(); 1287 assert(m.equals(member)); 1288 } 1289 return true; 1290 } 1291 1292 Class<?> memberDeclaringClassOrNull() { 1293 return (member == null) ? null : member.getDeclaringClass(); 1294 } 1295 1296 BasicType returnType() { 1297 return basicType(methodType().returnType()); 1298 } 1299 1300 BasicType parameterType(int n) { 1301 return basicType(methodType().parameterType(n)); 1302 } 1303 1304 int arity() { 1305 return methodType().parameterCount(); 1306 } 1307 1308 public String toString() { 1309 if (member == null) return String.valueOf(resolvedHandle); 1310 return member.getDeclaringClass().getSimpleName()+"."+member.getName(); 1311 } 1312 1313 public boolean isIdentity() { 1314 return this.equals(identity(returnType())); 1315 } 1316 1317 public boolean isConstantZero() { 1318 return this.equals(constantZero(returnType())); 1319 } 1320 1321 public MethodHandleImpl.Intrinsic intrinsicName() { 1322 return resolvedHandle == null ? MethodHandleImpl.Intrinsic.NONE 1323 : resolvedHandle.intrinsicName(); 1324 } 1325 } 1326 1327 public static String basicTypeSignature(MethodType type) { 1328 char[] sig = new char[type.parameterCount() + 2]; 1329 int sigp = 0; 1330 for (Class<?> pt : type.parameterList()) { 1331 sig[sigp++] = basicTypeChar(pt); 1332 } 1333 sig[sigp++] = '_'; 1334 sig[sigp++] = basicTypeChar(type.returnType()); 1335 assert(sigp == sig.length); 1336 return String.valueOf(sig); 1337 } 1338 public static String shortenSignature(String signature) { 1339 // Hack to make signatures more readable when they show up in method names. 1340 final int NO_CHAR = -1, MIN_RUN = 3; 1341 int c0, c1 = NO_CHAR, c1reps = 0; 1342 StringBuilder buf = null; 1343 int len = signature.length(); 1344 if (len < MIN_RUN) return signature; 1345 for (int i = 0; i <= len; i++) { 1346 // shift in the next char: 1347 c0 = c1; c1 = (i == len ? NO_CHAR : signature.charAt(i)); 1348 if (c1 == c0) { ++c1reps; continue; } 1349 // shift in the next count: 1350 int c0reps = c1reps; c1reps = 1; 1351 // end of a character run 1352 if (c0reps < MIN_RUN) { 1353 if (buf != null) { 1354 while (--c0reps >= 0) 1355 buf.append((char)c0); 1356 } 1357 continue; 1358 } 1359 // found three or more in a row 1360 if (buf == null) 1361 buf = new StringBuilder().append(signature, 0, i - c0reps); 1362 buf.append((char)c0).append(c0reps); 1363 } 1364 return (buf == null) ? signature : buf.toString(); 1365 } 1366 1367 static final class Name { 1368 final BasicType type; 1369 private short index; 1370 final NamedFunction function; 1371 final Object constraint; // additional type information, if not null 1372 @Stable final Object[] arguments; 1373 1374 private Name(int index, BasicType type, NamedFunction function, Object[] arguments) { 1375 this.index = (short)index; 1376 this.type = type; 1377 this.function = function; 1378 this.arguments = arguments; 1379 this.constraint = null; 1380 assert(this.index == index); 1381 } 1382 private Name(Name that, Object constraint) { 1383 this.index = that.index; 1384 this.type = that.type; 1385 this.function = that.function; 1386 this.arguments = that.arguments; 1387 this.constraint = constraint; 1388 assert(constraint == null || isParam()); // only params have constraints 1389 assert(constraint == null || constraint instanceof BoundMethodHandle.SpeciesData || constraint instanceof Class); 1390 } 1391 Name(MethodHandle function, Object... arguments) { 1392 this(new NamedFunction(function), arguments); 1393 } 1394 Name(MethodType functionType, Object... arguments) { 1395 this(new NamedFunction(functionType), arguments); 1396 assert(arguments[0] instanceof Name && ((Name)arguments[0]).type == L_TYPE); 1397 } 1398 Name(MemberName function, Object... arguments) { 1399 this(new NamedFunction(function), arguments); 1400 } 1401 Name(NamedFunction function, Object... arguments) { 1402 this(-1, function.returnType(), function, arguments = Arrays.copyOf(arguments, arguments.length, Object[].class)); 1403 assert(arguments.length == function.arity()) : "arity mismatch: arguments.length=" + arguments.length + " == function.arity()=" + function.arity() + " in " + debugString(); 1404 for (int i = 0; i < arguments.length; i++) 1405 assert(typesMatch(function.parameterType(i), arguments[i])) : "types don't match: function.parameterType(" + i + ")=" + function.parameterType(i) + ", arguments[" + i + "]=" + arguments[i] + " in " + debugString(); 1406 } 1407 /** Create a raw parameter of the given type, with an expected index. */ 1408 Name(int index, BasicType type) { 1409 this(index, type, null, null); 1410 } 1411 /** Create a raw parameter of the given type. */ 1412 Name(BasicType type) { this(-1, type); } 1413 1414 BasicType type() { return type; } 1415 int index() { return index; } 1416 boolean initIndex(int i) { 1417 if (index != i) { 1418 if (index != -1) return false; 1419 index = (short)i; 1420 } 1421 return true; 1422 } 1423 char typeChar() { 1424 return type.btChar; 1425 } 1426 1427 void resolve() { 1428 if (function != null) 1429 function.resolve(); 1430 } 1431 1432 Name newIndex(int i) { 1433 if (initIndex(i)) return this; 1434 return cloneWithIndex(i); 1435 } 1436 Name cloneWithIndex(int i) { 1437 Object[] newArguments = (arguments == null) ? null : arguments.clone(); 1438 return new Name(i, type, function, newArguments).withConstraint(constraint); 1439 } 1440 Name withConstraint(Object constraint) { 1441 if (constraint == this.constraint) return this; 1442 return new Name(this, constraint); 1443 } 1444 Name replaceName(Name oldName, Name newName) { // FIXME: use replaceNames uniformly 1445 if (oldName == newName) return this; 1446 @SuppressWarnings("LocalVariableHidesMemberVariable") 1447 Object[] arguments = this.arguments; 1448 if (arguments == null) return this; 1449 boolean replaced = false; 1450 for (int j = 0; j < arguments.length; j++) { 1451 if (arguments[j] == oldName) { 1452 if (!replaced) { 1453 replaced = true; 1454 arguments = arguments.clone(); 1455 } 1456 arguments[j] = newName; 1457 } 1458 } 1459 if (!replaced) return this; 1460 return new Name(function, arguments); 1461 } 1462 /** In the arguments of this Name, replace oldNames[i] pairwise by newNames[i]. 1463 * Limit such replacements to {@code start<=i<end}. Return possibly changed self. 1464 */ 1465 Name replaceNames(Name[] oldNames, Name[] newNames, int start, int end) { 1466 if (start >= end) return this; 1467 @SuppressWarnings("LocalVariableHidesMemberVariable") 1468 Object[] arguments = this.arguments; 1469 boolean replaced = false; 1470 eachArg: 1471 for (int j = 0; j < arguments.length; j++) { 1472 if (arguments[j] instanceof Name) { 1473 Name n = (Name) arguments[j]; 1474 int check = n.index; 1475 // harmless check to see if the thing is already in newNames: 1476 if (check >= 0 && check < newNames.length && n == newNames[check]) 1477 continue eachArg; 1478 // n might not have the correct index: n != oldNames[n.index]. 1479 for (int i = start; i < end; i++) { 1480 if (n == oldNames[i]) { 1481 if (n == newNames[i]) 1482 continue eachArg; 1483 if (!replaced) { 1484 replaced = true; 1485 arguments = arguments.clone(); 1486 } 1487 arguments[j] = newNames[i]; 1488 continue eachArg; 1489 } 1490 } 1491 } 1492 } 1493 if (!replaced) return this; 1494 return new Name(function, arguments); 1495 } 1496 void internArguments() { 1497 @SuppressWarnings("LocalVariableHidesMemberVariable") 1498 Object[] arguments = this.arguments; 1499 for (int j = 0; j < arguments.length; j++) { 1500 if (arguments[j] instanceof Name) { 1501 Name n = (Name) arguments[j]; 1502 if (n.isParam() && n.index < INTERNED_ARGUMENT_LIMIT) 1503 arguments[j] = internArgument(n); 1504 } 1505 } 1506 } 1507 boolean isParam() { 1508 return function == null; 1509 } 1510 boolean isConstantZero() { 1511 return !isParam() && arguments.length == 0 && function.isConstantZero(); 1512 } 1513 1514 public String toString() { 1515 return (isParam()?"a":"t")+(index >= 0 ? index : System.identityHashCode(this))+":"+typeChar(); 1516 } 1517 public String debugString() { 1518 String s = paramString(); 1519 return (function == null) ? s : s + "=" + exprString(); 1520 } 1521 public String paramString() { 1522 String s = toString(); 1523 Object c = constraint; 1524 if (c == null) 1525 return s; 1526 if (c instanceof Class) c = ((Class<?>)c).getSimpleName(); 1527 return s + "/" + c; 1528 } 1529 public String exprString() { 1530 if (function == null) return toString(); 1531 StringBuilder buf = new StringBuilder(function.toString()); 1532 buf.append("("); 1533 String cma = ""; 1534 for (Object a : arguments) { 1535 buf.append(cma); cma = ","; 1536 if (a instanceof Name || a instanceof Integer) 1537 buf.append(a); 1538 else 1539 buf.append("(").append(a).append(")"); 1540 } 1541 buf.append(")"); 1542 return buf.toString(); 1543 } 1544 1545 static boolean typesMatch(BasicType parameterType, Object object) { 1546 if (object instanceof Name) { 1547 return ((Name)object).type == parameterType; 1548 } 1549 switch (parameterType) { 1550 case I_TYPE: return object instanceof Integer; 1551 case J_TYPE: return object instanceof Long; 1552 case F_TYPE: return object instanceof Float; 1553 case D_TYPE: return object instanceof Double; 1554 } 1555 assert(parameterType == L_TYPE); 1556 return true; 1557 } 1558 1559 /** Return the index of the last occurrence of n in the argument array. 1560 * Return -1 if the name is not used. 1561 */ 1562 int lastUseIndex(Name n) { 1563 if (arguments == null) return -1; 1564 for (int i = arguments.length; --i >= 0; ) { 1565 if (arguments[i] == n) return i; 1566 } 1567 return -1; 1568 } 1569 1570 /** Return the number of occurrences of n in the argument array. 1571 * Return 0 if the name is not used. 1572 */ 1573 int useCount(Name n) { 1574 if (arguments == null) return 0; 1575 int count = 0; 1576 for (int i = arguments.length; --i >= 0; ) { 1577 if (arguments[i] == n) ++count; 1578 } 1579 return count; 1580 } 1581 1582 boolean contains(Name n) { 1583 return this == n || lastUseIndex(n) >= 0; 1584 } 1585 1586 public boolean equals(Name that) { 1587 if (this == that) return true; 1588 if (isParam()) 1589 // each parameter is a unique atom 1590 return false; // this != that 1591 return 1592 //this.index == that.index && 1593 this.type == that.type && 1594 this.function.equals(that.function) && 1595 Arrays.equals(this.arguments, that.arguments); 1596 } 1597 @Override 1598 public boolean equals(Object x) { 1599 return x instanceof Name && equals((Name)x); 1600 } 1601 @Override 1602 public int hashCode() { 1603 if (isParam()) 1604 return index | (type.ordinal() << 8); 1605 return function.hashCode() ^ Arrays.hashCode(arguments); 1606 } 1607 } 1608 1609 /** Return the index of the last name which contains n as an argument. 1610 * Return -1 if the name is not used. Return names.length if it is the return value. 1611 */ 1612 int lastUseIndex(Name n) { 1613 int ni = n.index, nmax = names.length; 1614 assert(names[ni] == n); 1615 if (result == ni) return nmax; // live all the way beyond the end 1616 for (int i = nmax; --i > ni; ) { 1617 if (names[i].lastUseIndex(n) >= 0) 1618 return i; 1619 } 1620 return -1; 1621 } 1622 1623 /** Return the number of times n is used as an argument or return value. */ 1624 int useCount(Name n) { 1625 int ni = n.index, nmax = names.length; 1626 int end = lastUseIndex(n); 1627 if (end < 0) return 0; 1628 int count = 0; 1629 if (end == nmax) { count++; end--; } 1630 int beg = n.index() + 1; 1631 if (beg < arity) beg = arity; 1632 for (int i = beg; i <= end; i++) { 1633 count += names[i].useCount(n); 1634 } 1635 return count; 1636 } 1637 1638 static Name argument(int which, char type) { 1639 return argument(which, basicType(type)); 1640 } 1641 static Name argument(int which, BasicType type) { 1642 if (which >= INTERNED_ARGUMENT_LIMIT) 1643 return new Name(which, type); 1644 return INTERNED_ARGUMENTS[type.ordinal()][which]; 1645 } 1646 static Name internArgument(Name n) { 1647 assert(n.isParam()) : "not param: " + n; 1648 assert(n.index < INTERNED_ARGUMENT_LIMIT); 1649 if (n.constraint != null) return n; 1650 return argument(n.index, n.type); 1651 } 1652 static Name[] arguments(int extra, String types) { 1653 int length = types.length(); 1654 Name[] names = new Name[length + extra]; 1655 for (int i = 0; i < length; i++) 1656 names[i] = argument(i, types.charAt(i)); 1657 return names; 1658 } 1659 static Name[] arguments(int extra, char... types) { 1660 int length = types.length; 1661 Name[] names = new Name[length + extra]; 1662 for (int i = 0; i < length; i++) 1663 names[i] = argument(i, types[i]); 1664 return names; 1665 } 1666 static Name[] arguments(int extra, List<Class<?>> types) { 1667 int length = types.size(); 1668 Name[] names = new Name[length + extra]; 1669 for (int i = 0; i < length; i++) 1670 names[i] = argument(i, basicType(types.get(i))); 1671 return names; 1672 } 1673 static Name[] arguments(int extra, Class<?>... types) { 1674 int length = types.length; 1675 Name[] names = new Name[length + extra]; 1676 for (int i = 0; i < length; i++) 1677 names[i] = argument(i, basicType(types[i])); 1678 return names; 1679 } 1680 static Name[] arguments(int extra, MethodType types) { 1681 int length = types.parameterCount(); 1682 Name[] names = new Name[length + extra]; 1683 for (int i = 0; i < length; i++) 1684 names[i] = argument(i, basicType(types.parameterType(i))); 1685 return names; 1686 } 1687 static final int INTERNED_ARGUMENT_LIMIT = 10; 1688 private static final Name[][] INTERNED_ARGUMENTS 1689 = new Name[ARG_TYPE_LIMIT][INTERNED_ARGUMENT_LIMIT]; 1690 static { 1691 for (BasicType type : BasicType.ARG_TYPES) { 1692 int ord = type.ordinal(); 1693 for (int i = 0; i < INTERNED_ARGUMENTS[ord].length; i++) { 1694 INTERNED_ARGUMENTS[ord][i] = new Name(i, type); 1695 } 1696 } 1697 } 1698 1699 private static final MemberName.Factory IMPL_NAMES = MemberName.getFactory(); 1700 1701 static LambdaForm identityForm(BasicType type) { 1702 return LF_identityForm[type.ordinal()]; 1703 } 1704 static LambdaForm zeroForm(BasicType type) { 1705 return LF_zeroForm[type.ordinal()]; 1706 } 1707 static NamedFunction identity(BasicType type) { 1708 return NF_identity[type.ordinal()]; 1709 } 1710 static NamedFunction constantZero(BasicType type) { 1711 return NF_zero[type.ordinal()]; 1712 } 1713 private static final LambdaForm[] LF_identityForm = new LambdaForm[TYPE_LIMIT]; 1714 private static final LambdaForm[] LF_zeroForm = new LambdaForm[TYPE_LIMIT]; 1715 private static final NamedFunction[] NF_identity = new NamedFunction[TYPE_LIMIT]; 1716 private static final NamedFunction[] NF_zero = new NamedFunction[TYPE_LIMIT]; 1717 private static void createIdentityForms() { 1718 for (BasicType type : BasicType.ALL_TYPES) { 1719 int ord = type.ordinal(); 1720 char btChar = type.basicTypeChar(); 1721 boolean isVoid = (type == V_TYPE); 1722 Class<?> btClass = type.btClass; 1723 MethodType zeType = MethodType.methodType(btClass); 1724 MethodType idType = isVoid ? zeType : zeType.appendParameterTypes(btClass); 1725 1726 // Look up some symbolic names. It might not be necessary to have these, 1727 // but if we need to emit direct references to bytecodes, it helps. 1728 // Zero is built from a call to an identity function with a constant zero input. 1729 MemberName idMem = new MemberName(LambdaForm.class, "identity_"+btChar, idType, REF_invokeStatic); 1730 MemberName zeMem = new MemberName(LambdaForm.class, "zero_"+btChar, zeType, REF_invokeStatic); 1731 try { 1732 zeMem = IMPL_NAMES.resolveOrFail(REF_invokeStatic, zeMem, null, NoSuchMethodException.class); 1733 idMem = IMPL_NAMES.resolveOrFail(REF_invokeStatic, idMem, null, NoSuchMethodException.class); 1734 } catch (IllegalAccessException|NoSuchMethodException ex) { 1735 throw newInternalError(ex); 1736 } 1737 1738 NamedFunction idFun = new NamedFunction(idMem); 1739 LambdaForm idForm; 1740 if (isVoid) { 1741 Name[] idNames = new Name[] { argument(0, L_TYPE) }; 1742 idForm = new LambdaForm(idMem.getName(), 1, idNames, VOID_RESULT); 1743 } else { 1744 Name[] idNames = new Name[] { argument(0, L_TYPE), argument(1, type) }; 1745 idForm = new LambdaForm(idMem.getName(), 2, idNames, 1); 1746 } 1747 LF_identityForm[ord] = idForm; 1748 NF_identity[ord] = idFun; 1749 1750 NamedFunction zeFun = new NamedFunction(zeMem); 1751 LambdaForm zeForm; 1752 if (isVoid) { 1753 zeForm = idForm; 1754 } else { 1755 Object zeValue = Wrapper.forBasicType(btChar).zero(); 1756 Name[] zeNames = new Name[] { argument(0, L_TYPE), new Name(idFun, zeValue) }; 1757 zeForm = new LambdaForm(zeMem.getName(), 1, zeNames, 1); 1758 } 1759 LF_zeroForm[ord] = zeForm; 1760 NF_zero[ord] = zeFun; 1761 1762 assert(idFun.isIdentity()); 1763 assert(zeFun.isConstantZero()); 1764 assert(new Name(zeFun).isConstantZero()); 1765 } 1766 1767 // Do this in a separate pass, so that SimpleMethodHandle.make can see the tables. 1768 for (BasicType type : BasicType.ALL_TYPES) { 1769 int ord = type.ordinal(); 1770 NamedFunction idFun = NF_identity[ord]; 1771 LambdaForm idForm = LF_identityForm[ord]; 1772 MemberName idMem = idFun.member; 1773 idFun.resolvedHandle = SimpleMethodHandle.make(idMem.getInvocationType(), idForm); 1774 1775 NamedFunction zeFun = NF_zero[ord]; 1776 LambdaForm zeForm = LF_zeroForm[ord]; 1777 MemberName zeMem = zeFun.member; 1778 zeFun.resolvedHandle = SimpleMethodHandle.make(zeMem.getInvocationType(), zeForm); 1779 1780 assert(idFun.isIdentity()); 1781 assert(zeFun.isConstantZero()); 1782 assert(new Name(zeFun).isConstantZero()); 1783 } 1784 } 1785 1786 // Avoid appealing to ValueConversions at bootstrap time: 1787 private static int identity_I(int x) { return x; } 1788 private static long identity_J(long x) { return x; } 1789 private static float identity_F(float x) { return x; } 1790 private static double identity_D(double x) { return x; } 1791 private static Object identity_L(Object x) { return x; } 1792 private static void identity_V() { return; } // same as zeroV, but that's OK 1793 private static int zero_I() { return 0; } 1794 private static long zero_J() { return 0; } 1795 private static float zero_F() { return 0; } 1796 private static double zero_D() { return 0; } 1797 private static Object zero_L() { return null; } 1798 private static void zero_V() { return; } 1799 1800 /** 1801 * Internal marker for byte-compiled LambdaForms. 1802 */ 1803 /*non-public*/ 1804 @Target(ElementType.METHOD) 1805 @Retention(RetentionPolicy.RUNTIME) 1806 @interface Compiled { 1807 } 1808 1809 /** 1810 * Internal marker for LambdaForm interpreter frames. 1811 */ 1812 /*non-public*/ 1813 @Target(ElementType.METHOD) 1814 @Retention(RetentionPolicy.RUNTIME) 1815 @interface Hidden { 1816 } 1817 1818 /** 1819 * Internal marker which signals JIT that gathered profile is mostly useless. 1820 */ 1821 /*non-public*/ 1822 @Target(ElementType.METHOD) 1823 @Retention(RetentionPolicy.RUNTIME) 1824 @interface Shared { 1825 } 1826 1827 private static final HashMap<String,Integer> DEBUG_NAME_COUNTERS; 1828 static { 1829 if (debugEnabled()) 1830 DEBUG_NAME_COUNTERS = new HashMap<>(); 1831 else 1832 DEBUG_NAME_COUNTERS = null; 1833 } 1834 1835 // Put this last, so that previous static inits can run before. 1836 static { 1837 createIdentityForms(); 1838 if (USE_PREDEFINED_INTERPRET_METHODS) 1839 computeInitialPreparedForms(); 1840 NamedFunction.initializeInvokers(); 1841 } 1842 1843 // The following hack is necessary in order to suppress TRACE_INTERPRETER 1844 // during execution of the static initializes of this class. 1845 // Turning on TRACE_INTERPRETER too early will cause 1846 // stack overflows and other misbehavior during attempts to trace events 1847 // that occur during LambdaForm.<clinit>. 1848 // Therefore, do not move this line higher in this file, and do not remove. 1849 private static final boolean TRACE_INTERPRETER = MethodHandleStatics.TRACE_INTERPRETER; 1850 }