1/* 2 * Copyright (c) 2010, 2014, 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 26package jdk.nashorn.internal.runtime; 27 28import static jdk.nashorn.internal.lookup.Lookup.MH; 29 30import java.io.IOException; 31import java.io.ObjectOutputStream; 32import java.io.Serializable; 33import java.lang.invoke.MethodHandle; 34import java.lang.invoke.MethodHandles; 35import java.lang.invoke.MethodType; 36import java.lang.ref.Reference; 37import java.lang.ref.SoftReference; 38import java.util.Collection; 39import java.util.Collections; 40import java.util.HashSet; 41import java.util.IdentityHashMap; 42import java.util.Map; 43import java.util.Set; 44import java.util.TreeMap; 45import java.util.concurrent.ExecutorService; 46import java.util.concurrent.LinkedBlockingDeque; 47import java.util.concurrent.ThreadPoolExecutor; 48import java.util.concurrent.TimeUnit; 49import jdk.nashorn.internal.codegen.Compiler; 50import jdk.nashorn.internal.codegen.Compiler.CompilationPhases; 51import jdk.nashorn.internal.codegen.CompilerConstants; 52import jdk.nashorn.internal.codegen.FunctionSignature; 53import jdk.nashorn.internal.codegen.Namespace; 54import jdk.nashorn.internal.codegen.OptimisticTypesPersistence; 55import jdk.nashorn.internal.codegen.TypeMap; 56import jdk.nashorn.internal.codegen.types.Type; 57import jdk.nashorn.internal.ir.Block; 58import jdk.nashorn.internal.ir.ForNode; 59import jdk.nashorn.internal.ir.FunctionNode; 60import jdk.nashorn.internal.ir.IdentNode; 61import jdk.nashorn.internal.ir.LexicalContext; 62import jdk.nashorn.internal.ir.Node; 63import jdk.nashorn.internal.ir.SwitchNode; 64import jdk.nashorn.internal.ir.Symbol; 65import jdk.nashorn.internal.ir.TryNode; 66import jdk.nashorn.internal.ir.visitor.SimpleNodeVisitor; 67import jdk.nashorn.internal.objects.Global; 68import jdk.nashorn.internal.parser.Parser; 69import jdk.nashorn.internal.parser.Token; 70import jdk.nashorn.internal.parser.TokenType; 71import jdk.nashorn.internal.runtime.linker.NameCodec; 72import jdk.nashorn.internal.runtime.logging.DebugLogger; 73import jdk.nashorn.internal.runtime.logging.Loggable; 74import jdk.nashorn.internal.runtime.logging.Logger; 75import jdk.nashorn.internal.runtime.options.Options; 76/** 77 * This is a subclass that represents a script function that may be regenerated, 78 * for example with specialization based on call site types, or lazily generated. 79 * The common denominator is that it can get new invokers during its lifespan, 80 * unlike {@code FinalScriptFunctionData} 81 */ 82@Logger(name="recompile") 83public final class RecompilableScriptFunctionData extends ScriptFunctionData implements Loggable { 84 /** Prefix used for all recompiled script classes */ 85 public static final String RECOMPILATION_PREFIX = "Recompilation$"; 86 87 private static final ExecutorService astSerializerExecutorService = createAstSerializerExecutorService(); 88 89 /** Unique function node id for this function node */ 90 private final int functionNodeId; 91 92 private final String functionName; 93 94 /** The line number where this function begins. */ 95 private final int lineNumber; 96 97 /** Source from which FunctionNode was parsed. */ 98 private transient Source source; 99 100 /** 101 * Cached form of the AST. Either a {@code SerializedAst} object used by split functions as they can't be 102 * reparsed from source, or a soft reference to a {@code FunctionNode} for other functions (it is safe 103 * to be cleared as they can be reparsed). 104 */ 105 private volatile transient Object cachedAst; 106 107 /** Token of this function within the source. */ 108 private final long token; 109 110 /** 111 * Represents the allocation strategy (property map, script object class, and method handle) for when 112 * this function is used as a constructor. Note that majority of functions (those not setting any this.* 113 * properties) will share a single canonical "default strategy" instance. 114 */ 115 private final AllocationStrategy allocationStrategy; 116 117 /** 118 * Opaque object representing parser state at the end of the function. Used when reparsing outer function 119 * to help with skipping parsing inner functions. 120 */ 121 private final Object endParserState; 122 123 /** Code installer used for all further recompilation/specialization of this ScriptFunction */ 124 private transient CodeInstaller installer; 125 126 private final Map<Integer, RecompilableScriptFunctionData> nestedFunctions; 127 128 /** Id to parent function if one exists */ 129 private RecompilableScriptFunctionData parent; 130 131 /** Copy of the {@link FunctionNode} flags. */ 132 private final int functionFlags; 133 134 private static final MethodHandles.Lookup LOOKUP = MethodHandles.lookup(); 135 136 private transient DebugLogger log; 137 138 private final Map<String, Integer> externalScopeDepths; 139 140 private final Set<String> internalSymbols; 141 142 private static final int GET_SET_PREFIX_LENGTH = "*et ".length(); 143 144 private static final long serialVersionUID = 4914839316174633726L; 145 146 /** 147 * Constructor - public as scripts use it 148 * 149 * @param functionNode functionNode that represents this function code 150 * @param installer installer for code regeneration versions of this function 151 * @param allocationStrategy strategy for the allocation behavior when this function is used as a constructor 152 * @param nestedFunctions nested function map 153 * @param externalScopeDepths external scope depths 154 * @param internalSymbols internal symbols to method, defined in its scope 155 */ 156 public RecompilableScriptFunctionData( 157 final FunctionNode functionNode, 158 final CodeInstaller installer, 159 final AllocationStrategy allocationStrategy, 160 final Map<Integer, RecompilableScriptFunctionData> nestedFunctions, 161 final Map<String, Integer> externalScopeDepths, 162 final Set<String> internalSymbols) { 163 164 super(functionName(functionNode), 165 Math.min(functionNode.getParameters().size(), MAX_ARITY), 166 getDataFlags(functionNode)); 167 168 this.functionName = functionNode.getName(); 169 this.lineNumber = functionNode.getLineNumber(); 170 this.functionFlags = functionNode.getFlags() | (functionNode.needsCallee() ? FunctionNode.NEEDS_CALLEE : 0); 171 this.functionNodeId = functionNode.getId(); 172 this.source = functionNode.getSource(); 173 this.endParserState = functionNode.getEndParserState(); 174 this.token = tokenFor(functionNode); 175 this.installer = installer; 176 this.allocationStrategy = allocationStrategy; 177 this.nestedFunctions = smallMap(nestedFunctions); 178 this.externalScopeDepths = smallMap(externalScopeDepths); 179 this.internalSymbols = smallSet(new HashSet<>(internalSymbols)); 180 181 for (final RecompilableScriptFunctionData nfn : nestedFunctions.values()) { 182 assert nfn.getParent() == null; 183 nfn.setParent(this); 184 } 185 186 createLogger(); 187 } 188 189 private static <K, V> Map<K, V> smallMap(final Map<K, V> map) { 190 if (map == null || map.isEmpty()) { 191 return Collections.emptyMap(); 192 } else if (map.size() == 1) { 193 final Map.Entry<K, V> entry = map.entrySet().iterator().next(); 194 return Collections.singletonMap(entry.getKey(), entry.getValue()); 195 } else { 196 return map; 197 } 198 } 199 200 private static <T> Set<T> smallSet(final Set<T> set) { 201 if (set == null || set.isEmpty()) { 202 return Collections.emptySet(); 203 } else if (set.size() == 1) { 204 return Collections.singleton(set.iterator().next()); 205 } else { 206 return set; 207 } 208 } 209 210 @Override 211 public DebugLogger getLogger() { 212 return log; 213 } 214 215 @Override 216 public DebugLogger initLogger(final Context ctxt) { 217 return ctxt.getLogger(this.getClass()); 218 } 219 220 /** 221 * Check if a symbol is internally defined in a function. For example 222 * if "undefined" is internally defined in the outermost program function, 223 * it has not been reassigned or overridden and can be optimized 224 * 225 * @param symbolName symbol name 226 * @return true if symbol is internal to this ScriptFunction 227 */ 228 229 public boolean hasInternalSymbol(final String symbolName) { 230 return internalSymbols.contains(symbolName); 231 } 232 233 /** 234 * Return the external symbol table 235 * @param symbolName symbol name 236 * @return the external symbol table with proto depths 237 */ 238 public int getExternalSymbolDepth(final String symbolName) { 239 final Integer depth = externalScopeDepths.get(symbolName); 240 return depth == null ? -1 : depth; 241 } 242 243 /** 244 * Returns the names of all external symbols this function uses. 245 * @return the names of all external symbols this function uses. 246 */ 247 public Set<String> getExternalSymbolNames() { 248 return Collections.unmodifiableSet(externalScopeDepths.keySet()); 249 } 250 251 /** 252 * Returns the opaque object representing the parser state at the end of this function's body, used to 253 * skip parsing this function when reparsing its containing outer function. 254 * @return the object representing the end parser state 255 */ 256 public Object getEndParserState() { 257 return endParserState; 258 } 259 260 /** 261 * Get the parent of this RecompilableScriptFunctionData. If we are 262 * a nested function, we have a parent. Note that "null" return value 263 * can also mean that we have a parent but it is unknown, so this can 264 * only be used for conservative assumptions. 265 * @return parent data, or null if non exists and also null IF UNKNOWN. 266 */ 267 public RecompilableScriptFunctionData getParent() { 268 return parent; 269 } 270 271 void setParent(final RecompilableScriptFunctionData parent) { 272 this.parent = parent; 273 } 274 275 @Override 276 String toSource() { 277 if (source != null && token != 0) { 278 return source.getString(Token.descPosition(token), Token.descLength(token)); 279 } 280 281 return "function " + (name == null ? "" : name) + "() { [native code] }"; 282 } 283 284 /** 285 * Initialize transient fields on deserialized instances 286 * 287 * @param src source 288 * @param inst code installer 289 */ 290 public void initTransients(final Source src, final CodeInstaller inst) { 291 if (this.source == null && this.installer == null) { 292 this.source = src; 293 this.installer = inst; 294 for (final RecompilableScriptFunctionData nested : nestedFunctions.values()) { 295 nested.initTransients(src, inst); 296 } 297 } else if (this.source != src || !this.installer.isCompatibleWith(inst)) { 298 // Existing values must be same as those passed as parameters 299 throw new IllegalArgumentException(); 300 } 301 } 302 303 @Override 304 public String toString() { 305 return super.toString() + '@' + functionNodeId; 306 } 307 308 @Override 309 public String toStringVerbose() { 310 final StringBuilder sb = new StringBuilder(); 311 312 sb.append("fnId=").append(functionNodeId).append(' '); 313 314 if (source != null) { 315 sb.append(source.getName()) 316 .append(':') 317 .append(lineNumber) 318 .append(' '); 319 } 320 321 return sb.toString() + super.toString(); 322 } 323 324 @Override 325 public String getFunctionName() { 326 return functionName; 327 } 328 329 @Override 330 public boolean inDynamicContext() { 331 return getFunctionFlag(FunctionNode.IN_DYNAMIC_CONTEXT); 332 } 333 334 private static String functionName(final FunctionNode fn) { 335 if (fn.isAnonymous()) { 336 return ""; 337 } 338 final FunctionNode.Kind kind = fn.getKind(); 339 if (kind == FunctionNode.Kind.GETTER || kind == FunctionNode.Kind.SETTER) { 340 final String name = NameCodec.decode(fn.getIdent().getName()); 341 return name.substring(GET_SET_PREFIX_LENGTH); 342 } 343 return fn.getIdent().getName(); 344 } 345 346 private static long tokenFor(final FunctionNode fn) { 347 final int position = Token.descPosition(fn.getFirstToken()); 348 final long lastToken = Token.withDelimiter(fn.getLastToken()); 349 // EOL uses length field to store the line number 350 final int length = Token.descPosition(lastToken) - position + (Token.descType(lastToken) == TokenType.EOL ? 0 : Token.descLength(lastToken)); 351 352 return Token.toDesc(TokenType.FUNCTION, position, length); 353 } 354 355 private static int getDataFlags(final FunctionNode functionNode) { 356 int flags = IS_CONSTRUCTOR; 357 if (functionNode.isStrict()) { 358 flags |= IS_STRICT; 359 } 360 if (functionNode.needsCallee()) { 361 flags |= NEEDS_CALLEE; 362 } 363 if (functionNode.usesThis() || functionNode.hasEval()) { 364 flags |= USES_THIS; 365 } 366 if (functionNode.isVarArg()) { 367 flags |= IS_VARIABLE_ARITY; 368 } 369 if (functionNode.getKind() == FunctionNode.Kind.GETTER || functionNode.getKind() == FunctionNode.Kind.SETTER) { 370 flags |= IS_PROPERTY_ACCESSOR; 371 } 372 if (functionNode.isMethod() || functionNode.isClassConstructor()) { 373 flags |= IS_ES6_METHOD; 374 } 375 return flags; 376 } 377 378 @Override 379 PropertyMap getAllocatorMap(final ScriptObject prototype) { 380 return allocationStrategy.getAllocatorMap(prototype); 381 } 382 383 @Override 384 ScriptObject allocate(final PropertyMap map) { 385 return allocationStrategy.allocate(map); 386 } 387 388 FunctionNode reparse() { 389 final FunctionNode cachedFunction = getCachedAst(); 390 if (cachedFunction != null) { 391 assert cachedFunction.isCached(); 392 return cachedFunction; 393 } 394 395 final int descPosition = Token.descPosition(token); 396 final Context context = Context.getContextTrusted(); 397 final Parser parser = new Parser( 398 context.getEnv(), 399 source, 400 new Context.ThrowErrorManager(), 401 isStrict(), 402 // source starts at line 0, so even though lineNumber is the correct declaration line, back off 403 // one to make it exclusive 404 lineNumber - 1, 405 context.getLogger(Parser.class)); 406 407 if (getFunctionFlag(FunctionNode.IS_ANONYMOUS)) { 408 parser.setFunctionName(functionName); 409 } 410 parser.setReparsedFunction(this); 411 412 final FunctionNode program = parser.parse(CompilerConstants.PROGRAM.symbolName(), descPosition, 413 Token.descLength(token), flags); 414 // Parser generates a program AST even if we're recompiling a single function, so when we are only 415 // recompiling a single function, extract it from the program. 416 return (isProgram() ? program : extractFunctionFromScript(program)).setName(null, functionName); 417 } 418 419 private FunctionNode getCachedAst() { 420 final Object lCachedAst = cachedAst; 421 // Are we softly caching the AST? 422 if (lCachedAst instanceof Reference<?>) { 423 final FunctionNode fn = (FunctionNode)((Reference<?>)lCachedAst).get(); 424 if (fn != null) { 425 // Yes we are - this is fast 426 return cloneSymbols(fn); 427 } 428 // Are we strongly caching a serialized AST (for split functions only)? 429 } else if (lCachedAst instanceof SerializedAst) { 430 final SerializedAst serializedAst = (SerializedAst)lCachedAst; 431 // Even so, are we also softly caching the AST? 432 final FunctionNode cachedFn = serializedAst.cachedAst == null ? null : serializedAst.cachedAst.get(); 433 if (cachedFn != null) { 434 // Yes we are - this is fast 435 return cloneSymbols(cachedFn); 436 } 437 final FunctionNode deserializedFn = deserialize(serializedAst.serializedAst); 438 // Softly cache after deserialization, maybe next time we won't need to deserialize 439 serializedAst.cachedAst = new SoftReference<>(deserializedFn); 440 return deserializedFn; 441 } 442 // No cached representation; return null for reparsing 443 return null; 444 } 445 446 /** 447 * Sets the AST to cache in this function 448 * @param astToCache the new AST to cache 449 */ 450 public void setCachedAst(final FunctionNode astToCache) { 451 assert astToCache.getId() == functionNodeId; // same function 452 assert !(cachedAst instanceof SerializedAst); // Can't overwrite serialized AST 453 454 final boolean isSplit = astToCache.isSplit(); 455 // If we're caching a split function, we're doing it in the eager pass, hence there can be no other 456 // cached representation already. In other words, isSplit implies cachedAst == null. 457 assert !isSplit || cachedAst == null; // 458 459 final FunctionNode symbolClonedAst = cloneSymbols(astToCache); 460 final Reference<FunctionNode> ref = new SoftReference<>(symbolClonedAst); 461 cachedAst = ref; 462 463 // Asynchronously serialize split functions. 464 if (isSplit) { 465 astSerializerExecutorService.execute(() -> { 466 cachedAst = new SerializedAst(symbolClonedAst, ref); 467 }); 468 } 469 } 470 471 /** 472 * Creates the AST serializer executor service used for in-memory serialization of split functions' ASTs. 473 * It is created with an unbounded queue (so it can queue any number of pending tasks). Its core and max 474 * threads is the same, but they are all allowed to time out so when there's no work, they can all go 475 * away. The threads will be daemons, and they will time out if idle for a minute. Their priority is also 476 * slightly lower than normal priority as we'd prefer the CPU to keep running the program; serializing 477 * split function is a memory conservation measure (it allows us to release the AST), it can wait a bit. 478 * @return an executor service with above described characteristics. 479 */ 480 private static ExecutorService createAstSerializerExecutorService() { 481 final int threads = Math.max(1, Options.getIntProperty("nashorn.serialize.threads", Runtime.getRuntime().availableProcessors() / 2)); 482 final ThreadPoolExecutor service = new ThreadPoolExecutor(threads, threads, 1, TimeUnit.MINUTES, new LinkedBlockingDeque<>(), 483 (r) -> { 484 final Thread t = new Thread(r, "Nashorn AST Serializer"); 485 t.setDaemon(true); 486 t.setPriority(Thread.NORM_PRIORITY - 1); 487 return t; 488 }); 489 service.allowCoreThreadTimeOut(true); 490 return service; 491 } 492 493 /** 494 * A tuple of a serialized AST and a soft reference to a deserialized AST. This is used to cache split 495 * functions. Since split functions are altered from their source form, they can't be reparsed from 496 * source. While we could just use the {@code byte[]} representation in {@link RecompilableScriptFunctionData#cachedAst} 497 * we're using this tuple instead to also keep a deserialized AST around in memory to cut down on 498 * deserialization costs. 499 */ 500 private static class SerializedAst implements Serializable { 501 private final byte[] serializedAst; 502 private volatile transient Reference<FunctionNode> cachedAst; 503 504 private static final long serialVersionUID = 1L; 505 506 SerializedAst(final FunctionNode fn, final Reference<FunctionNode> cachedAst) { 507 this.serializedAst = AstSerializer.serialize(fn); 508 this.cachedAst = cachedAst; 509 } 510 } 511 512 private FunctionNode deserialize(final byte[] serializedAst) { 513 final ScriptEnvironment env = installer.getContext().getEnv(); 514 final Timing timing = env._timing; 515 final long t1 = System.nanoTime(); 516 try { 517 return AstDeserializer.deserialize(serializedAst).initializeDeserialized(source, new Namespace(env.getNamespace())); 518 } finally { 519 timing.accumulateTime("'Deserialize'", System.nanoTime() - t1); 520 } 521 } 522 523 private FunctionNode cloneSymbols(final FunctionNode fn) { 524 final IdentityHashMap<Symbol, Symbol> symbolReplacements = new IdentityHashMap<>(); 525 final boolean cached = fn.isCached(); 526 // blockDefinedSymbols is used to re-mark symbols defined outside the function as global. We only 527 // need to do this when we cache an eagerly parsed function (which currently means a split one, as we 528 // don't cache non-split functions from the eager pass); those already cached, or those not split 529 // don't need this step. 530 final Set<Symbol> blockDefinedSymbols = fn.isSplit() && !cached ? Collections.newSetFromMap(new IdentityHashMap<>()) : null; 531 FunctionNode newFn = (FunctionNode)fn.accept(new SimpleNodeVisitor() { 532 private Symbol getReplacement(final Symbol original) { 533 if (original == null) { 534 return null; 535 } 536 final Symbol existingReplacement = symbolReplacements.get(original); 537 if (existingReplacement != null) { 538 return existingReplacement; 539 } 540 final Symbol newReplacement = original.clone(); 541 symbolReplacements.put(original, newReplacement); 542 return newReplacement; 543 } 544 545 @Override 546 public Node leaveIdentNode(final IdentNode identNode) { 547 final Symbol oldSymbol = identNode.getSymbol(); 548 if (oldSymbol != null) { 549 final Symbol replacement = getReplacement(oldSymbol); 550 return identNode.setSymbol(replacement); 551 } 552 return identNode; 553 } 554 555 @Override 556 public Node leaveForNode(final ForNode forNode) { 557 return ensureUniqueLabels(forNode.setIterator(lc, getReplacement(forNode.getIterator()))); 558 } 559 560 @Override 561 public Node leaveSwitchNode(final SwitchNode switchNode) { 562 return ensureUniqueLabels(switchNode.setTag(lc, getReplacement(switchNode.getTag()))); 563 } 564 565 @Override 566 public Node leaveTryNode(final TryNode tryNode) { 567 return ensureUniqueLabels(tryNode.setException(lc, getReplacement(tryNode.getException()))); 568 } 569 570 @Override 571 public boolean enterBlock(final Block block) { 572 for(final Symbol symbol: block.getSymbols()) { 573 final Symbol replacement = getReplacement(symbol); 574 if (blockDefinedSymbols != null) { 575 blockDefinedSymbols.add(replacement); 576 } 577 } 578 return true; 579 } 580 581 @Override 582 public Node leaveBlock(final Block block) { 583 return ensureUniqueLabels(block.replaceSymbols(lc, symbolReplacements)); 584 } 585 586 @Override 587 public Node leaveFunctionNode(final FunctionNode functionNode) { 588 return functionNode.setParameters(lc, functionNode.visitParameters(this)); 589 } 590 591 @Override 592 protected Node leaveDefault(final Node node) { 593 return ensureUniqueLabels(node); 594 }; 595 596 private Node ensureUniqueLabels(final Node node) { 597 // If we're returning a cached AST, we must also ensure unique labels 598 return cached ? node.ensureUniqueLabels(lc) : node; 599 } 600 }); 601 602 if (blockDefinedSymbols != null) { 603 // Mark all symbols not defined in blocks as globals 604 Block newBody = null; 605 for(final Symbol symbol: symbolReplacements.values()) { 606 if(!blockDefinedSymbols.contains(symbol)) { 607 assert symbol.isScope(); // must be scope 608 assert externalScopeDepths.containsKey(symbol.getName()); // must be known to us as an external 609 // Register it in the function body symbol table as a new global symbol 610 symbol.setFlags((symbol.getFlags() & ~Symbol.KINDMASK) | Symbol.IS_GLOBAL); 611 if (newBody == null) { 612 newBody = newFn.getBody().copyWithNewSymbols(); 613 newFn = newFn.setBody(null, newBody); 614 } 615 assert newBody.getExistingSymbol(symbol.getName()) == null; // must not be defined in the body already 616 newBody.putSymbol(symbol); 617 } 618 } 619 } 620 return newFn.setCached(null); 621 } 622 623 private boolean getFunctionFlag(final int flag) { 624 return (functionFlags & flag) != 0; 625 } 626 627 private boolean isProgram() { 628 return getFunctionFlag(FunctionNode.IS_PROGRAM); 629 } 630 631 TypeMap typeMap(final MethodType fnCallSiteType) { 632 if (fnCallSiteType == null) { 633 return null; 634 } 635 636 if (CompiledFunction.isVarArgsType(fnCallSiteType)) { 637 return null; 638 } 639 640 return new TypeMap(functionNodeId, explicitParams(fnCallSiteType), needsCallee()); 641 } 642 643 private static ScriptObject newLocals(final ScriptObject runtimeScope) { 644 final ScriptObject locals = Global.newEmptyInstance(); 645 locals.setProto(runtimeScope); 646 return locals; 647 } 648 649 private Compiler getCompiler(final FunctionNode fn, final MethodType actualCallSiteType, final ScriptObject runtimeScope) { 650 return getCompiler(fn, actualCallSiteType, newLocals(runtimeScope), null, null); 651 } 652 653 /** 654 * Returns a code installer for installing new code. If we're using either optimistic typing or loader-per-compile, 655 * then asks for a code installer with a new class loader; otherwise just uses the current installer. We use 656 * a new class loader with optimistic typing so that deoptimized code can get reclaimed by GC. 657 * @return a code installer for installing new code. 658 */ 659 private CodeInstaller getInstallerForNewCode() { 660 final ScriptEnvironment env = installer.getContext().getEnv(); 661 return env._optimistic_types || env._loader_per_compile ? installer.getOnDemandCompilationInstaller() : installer; 662 } 663 664 Compiler getCompiler(final FunctionNode functionNode, final MethodType actualCallSiteType, 665 final ScriptObject runtimeScope, final Map<Integer, Type> invalidatedProgramPoints, 666 final int[] continuationEntryPoints) { 667 final TypeMap typeMap = typeMap(actualCallSiteType); 668 final Type[] paramTypes = typeMap == null ? null : typeMap.getParameterTypes(functionNodeId); 669 final Object typeInformationFile = OptimisticTypesPersistence.getLocationDescriptor(source, functionNodeId, paramTypes); 670 return Compiler.forOnDemandCompilation( 671 getInstallerForNewCode(), 672 functionNode.getSource(), // source 673 isStrict() | functionNode.isStrict(), // is strict 674 this, // compiledFunction, i.e. this RecompilableScriptFunctionData 675 typeMap, // type map 676 getEffectiveInvalidatedProgramPoints(invalidatedProgramPoints, typeInformationFile), // invalidated program points 677 typeInformationFile, 678 continuationEntryPoints, // continuation entry points 679 runtimeScope); // runtime scope 680 } 681 682 /** 683 * If the function being compiled already has its own invalidated program points map, use it. Otherwise, attempt to 684 * load invalidated program points map from the persistent type info cache. 685 * @param invalidatedProgramPoints the function's current invalidated program points map. Null if the function 686 * doesn't have it. 687 * @param typeInformationFile the object describing the location of the persisted type information. 688 * @return either the existing map, or a loaded map from the persistent type info cache, or a new empty map if 689 * neither an existing map or a persistent cached type info is available. 690 */ 691 @SuppressWarnings("unused") 692 private static Map<Integer, Type> getEffectiveInvalidatedProgramPoints( 693 final Map<Integer, Type> invalidatedProgramPoints, final Object typeInformationFile) { 694 if(invalidatedProgramPoints != null) { 695 return invalidatedProgramPoints; 696 } 697 final Map<Integer, Type> loadedProgramPoints = OptimisticTypesPersistence.load(typeInformationFile); 698 return loadedProgramPoints != null ? loadedProgramPoints : new TreeMap<Integer, Type>(); 699 } 700 701 private FunctionInitializer compileTypeSpecialization(final MethodType actualCallSiteType, final ScriptObject runtimeScope, final boolean persist) { 702 // We're creating an empty script object for holding local variables. AssignSymbols will populate it with 703 // explicit Undefined values for undefined local variables (see AssignSymbols#defineSymbol() and 704 // CompilationEnvironment#declareLocalSymbol()). 705 706 if (log.isEnabled()) { 707 log.info("Parameter type specialization of '", functionName, "' signature: ", actualCallSiteType); 708 } 709 710 final boolean persistentCache = persist && usePersistentCodeCache(); 711 String cacheKey = null; 712 if (persistentCache) { 713 final TypeMap typeMap = typeMap(actualCallSiteType); 714 final Type[] paramTypes = typeMap == null ? null : typeMap.getParameterTypes(functionNodeId); 715 cacheKey = CodeStore.getCacheKey(functionNodeId, paramTypes); 716 final CodeInstaller newInstaller = getInstallerForNewCode(); 717 final StoredScript script = newInstaller.loadScript(source, cacheKey); 718 719 if (script != null) { 720 Compiler.updateCompilationId(script.getCompilationId()); 721 return script.installFunction(this, newInstaller); 722 } 723 } 724 725 final FunctionNode fn = reparse(); 726 final Compiler compiler = getCompiler(fn, actualCallSiteType, runtimeScope); 727 final FunctionNode compiledFn = compiler.compile(fn, 728 fn.isCached() ? CompilationPhases.COMPILE_ALL_CACHED : CompilationPhases.COMPILE_ALL); 729 730 if (persist && !compiledFn.hasApplyToCallSpecialization()) { 731 compiler.persistClassInfo(cacheKey, compiledFn); 732 } 733 return new FunctionInitializer(compiledFn, compiler.getInvalidatedProgramPoints()); 734 } 735 736 boolean usePersistentCodeCache() { 737 return installer != null && installer.getContext().getEnv()._persistent_cache; 738 } 739 740 private MethodType explicitParams(final MethodType callSiteType) { 741 if (CompiledFunction.isVarArgsType(callSiteType)) { 742 return null; 743 } 744 745 final MethodType noCalleeThisType = callSiteType.dropParameterTypes(0, 2); // (callee, this) is always in call site type 746 final int callSiteParamCount = noCalleeThisType.parameterCount(); 747 748 // Widen parameters of reference types to Object as we currently don't care for specialization among reference 749 // types. E.g. call site saying (ScriptFunction, Object, String) should still link to (ScriptFunction, Object, Object) 750 final Class<?>[] paramTypes = noCalleeThisType.parameterArray(); 751 boolean changed = false; 752 for (int i = 0; i < paramTypes.length; ++i) { 753 final Class<?> paramType = paramTypes[i]; 754 if (!(paramType.isPrimitive() || paramType == Object.class)) { 755 paramTypes[i] = Object.class; 756 changed = true; 757 } 758 } 759 final MethodType generalized = changed ? MethodType.methodType(noCalleeThisType.returnType(), paramTypes) : noCalleeThisType; 760 761 if (callSiteParamCount < getArity()) { 762 return generalized.appendParameterTypes(Collections.<Class<?>>nCopies(getArity() - callSiteParamCount, Object.class)); 763 } 764 return generalized; 765 } 766 767 private FunctionNode extractFunctionFromScript(final FunctionNode script) { 768 final Set<FunctionNode> fns = new HashSet<>(); 769 script.getBody().accept(new SimpleNodeVisitor() { 770 @Override 771 public boolean enterFunctionNode(final FunctionNode fn) { 772 fns.add(fn); 773 return false; 774 } 775 }); 776 assert fns.size() == 1 : "got back more than one method in recompilation"; 777 final FunctionNode f = fns.iterator().next(); 778 assert f.getId() == functionNodeId; 779 if (!getFunctionFlag(FunctionNode.IS_DECLARED) && f.isDeclared()) { 780 return f.clearFlag(null, FunctionNode.IS_DECLARED); 781 } 782 return f; 783 } 784 785 private void logLookup(final boolean shouldLog, final MethodType targetType) { 786 if (shouldLog && log.isEnabled()) { 787 log.info("Looking up ", DebugLogger.quote(functionName), " type=", targetType); 788 } 789 } 790 791 private MethodHandle lookup(final FunctionInitializer fnInit, final boolean shouldLog) { 792 final MethodType type = fnInit.getMethodType(); 793 logLookup(shouldLog, type); 794 return lookupCodeMethod(fnInit.getCode(), type); 795 } 796 797 MethodHandle lookup(final FunctionNode fn) { 798 final MethodType type = new FunctionSignature(fn).getMethodType(); 799 logLookup(true, type); 800 return lookupCodeMethod(fn.getCompileUnit().getCode(), type); 801 } 802 803 MethodHandle lookupCodeMethod(final Class<?> codeClass, final MethodType targetType) { 804 return MH.findStatic(LOOKUP, codeClass, functionName, targetType); 805 } 806 807 /** 808 * Initializes this function data with the eagerly generated version of the code. This method can only be invoked 809 * by the compiler internals in Nashorn and is public for implementation reasons only. Attempting to invoke it 810 * externally will result in an exception. 811 * 812 * @param functionNode FunctionNode for this data 813 */ 814 public void initializeCode(final FunctionNode functionNode) { 815 // Since the method is public, we double-check that we aren't invoked with an inappropriate compile unit. 816 if (!code.isEmpty() || functionNode.getId() != functionNodeId || !functionNode.getCompileUnit().isInitializing(this, functionNode)) { 817 throw new IllegalStateException(name); 818 } 819 addCode(lookup(functionNode), null, null, functionNode.getFlags()); 820 } 821 822 /** 823 * Initializes this function with the given function code initializer. 824 * @param initializer function code initializer 825 */ 826 void initializeCode(final FunctionInitializer initializer) { 827 addCode(lookup(initializer, true), null, null, initializer.getFlags()); 828 } 829 830 private CompiledFunction addCode(final MethodHandle target, final Map<Integer, Type> invalidatedProgramPoints, 831 final MethodType callSiteType, final int fnFlags) { 832 final CompiledFunction cfn = new CompiledFunction(target, this, invalidatedProgramPoints, callSiteType, fnFlags); 833 assert noDuplicateCode(cfn) : "duplicate code"; 834 code.add(cfn); 835 return cfn; 836 } 837 838 /** 839 * Add code with specific call site type. It will adapt the type of the looked up method handle to fit the call site 840 * type. This is necessary because even if we request a specialization that takes an "int" parameter, we might end 841 * up getting one that takes a "double" etc. because of internal function logic causes widening (e.g. assignment of 842 * a wider value to the parameter variable). However, we use the method handle type for matching subsequent lookups 843 * for the same specialization, so we must adapt the handle to the expected type. 844 * @param fnInit the function 845 * @param callSiteType the call site type 846 * @return the compiled function object, with its type matching that of the call site type. 847 */ 848 private CompiledFunction addCode(final FunctionInitializer fnInit, final MethodType callSiteType) { 849 if (isVariableArity()) { 850 return addCode(lookup(fnInit, true), fnInit.getInvalidatedProgramPoints(), callSiteType, fnInit.getFlags()); 851 } 852 853 final MethodHandle handle = lookup(fnInit, true); 854 final MethodType fromType = handle.type(); 855 MethodType toType = needsCallee(fromType) ? callSiteType.changeParameterType(0, ScriptFunction.class) : callSiteType.dropParameterTypes(0, 1); 856 toType = toType.changeReturnType(fromType.returnType()); 857 858 final int toCount = toType.parameterCount(); 859 final int fromCount = fromType.parameterCount(); 860 final int minCount = Math.min(fromCount, toCount); 861 for(int i = 0; i < minCount; ++i) { 862 final Class<?> fromParam = fromType.parameterType(i); 863 final Class<?> toParam = toType.parameterType(i); 864 // If method has an Object parameter, but call site had String, preserve it as Object. No need to narrow it 865 // artificially. Note that this is related to how CompiledFunction.matchesCallSite() works, specifically 866 // the fact that various reference types compare to equal (see "fnType.isEquivalentTo(csType)" there). 867 if (fromParam != toParam && !fromParam.isPrimitive() && !toParam.isPrimitive()) { 868 assert fromParam.isAssignableFrom(toParam); 869 toType = toType.changeParameterType(i, fromParam); 870 } 871 } 872 if (fromCount > toCount) { 873 toType = toType.appendParameterTypes(fromType.parameterList().subList(toCount, fromCount)); 874 } else if (fromCount < toCount) { 875 toType = toType.dropParameterTypes(fromCount, toCount); 876 } 877 878 return addCode(lookup(fnInit, false).asType(toType), fnInit.getInvalidatedProgramPoints(), callSiteType, fnInit.getFlags()); 879 } 880 881 /** 882 * Returns the return type of a function specialization for particular parameter types.<br> 883 * <b>Be aware that the way this is implemented, it forces full materialization (compilation and installation) of 884 * code for that specialization.</b> 885 * @param callSiteType the parameter types at the call site. It must include the mandatory {@code callee} and 886 * {@code this} parameters, so it needs to start with at least {@code ScriptFunction.class} and 887 * {@code Object.class} class. Since the return type of the function is calculated from the code itself, it is 888 * irrelevant and should be set to {@code Object.class}. 889 * @param runtimeScope a current runtime scope. Can be null but when it's present it will be used as a source of 890 * current runtime values that can improve the compiler's type speculations (and thus reduce the need for later 891 * recompilations) if the specialization is not already present and thus needs to be freshly compiled. 892 * @return the return type of the function specialization. 893 */ 894 public Class<?> getReturnType(final MethodType callSiteType, final ScriptObject runtimeScope) { 895 return getBest(callSiteType, runtimeScope, CompiledFunction.NO_FUNCTIONS).type().returnType(); 896 } 897 898 @Override 899 synchronized CompiledFunction getBest(final MethodType callSiteType, final ScriptObject runtimeScope, final Collection<CompiledFunction> forbidden, final boolean linkLogicOkay) { 900 assert isValidCallSite(callSiteType) : callSiteType; 901 902 CompiledFunction existingBest = pickFunction(callSiteType, false); 903 if (existingBest == null) { 904 existingBest = pickFunction(callSiteType, true); // try vararg last 905 } 906 if (existingBest == null) { 907 existingBest = addCode(compileTypeSpecialization(callSiteType, runtimeScope, true), callSiteType); 908 } 909 910 assert existingBest != null; 911 912 //if the best one is an apply to call, it has to match the callsite exactly 913 //or we need to regenerate 914 if (existingBest.isApplyToCall()) { 915 final CompiledFunction best = lookupExactApplyToCall(callSiteType); 916 if (best != null) { 917 return best; 918 } 919 920 // special case: we had an apply to call, but we failed to make it fit. 921 // Try to generate a specialized one for this callsite. It may 922 // be another apply to call specialization, or it may not, but whatever 923 // it is, it is a specialization that is guaranteed to fit 924 existingBest = addCode(compileTypeSpecialization(callSiteType, runtimeScope, false), callSiteType); 925 } 926 927 return existingBest; 928 } 929 930 @Override 931 public boolean needsCallee() { 932 return getFunctionFlag(FunctionNode.NEEDS_CALLEE); 933 } 934 935 /** 936 * Returns the {@link FunctionNode} flags associated with this function data. 937 * @return the {@link FunctionNode} flags associated with this function data. 938 */ 939 public int getFunctionFlags() { 940 return functionFlags; 941 } 942 943 @Override 944 MethodType getGenericType() { 945 // 2 is for (callee, this) 946 if (isVariableArity()) { 947 return MethodType.genericMethodType(2, true); 948 } 949 return MethodType.genericMethodType(2 + getArity()); 950 } 951 952 /** 953 * Return the function node id. 954 * @return the function node id 955 */ 956 public int getFunctionNodeId() { 957 return functionNodeId; 958 } 959 960 /** 961 * Get the source for the script 962 * @return source 963 */ 964 public Source getSource() { 965 return source; 966 } 967 968 /** 969 * Return a script function data based on a function id, either this function if 970 * the id matches or a nested function based on functionId. This goes down into 971 * nested functions until all leaves are exhausted. 972 * 973 * @param functionId function id 974 * @return script function data or null if invalid id 975 */ 976 public RecompilableScriptFunctionData getScriptFunctionData(final int functionId) { 977 if (functionId == functionNodeId) { 978 return this; 979 } 980 RecompilableScriptFunctionData data; 981 982 data = nestedFunctions == null ? null : nestedFunctions.get(functionId); 983 if (data != null) { 984 return data; 985 } 986 for (final RecompilableScriptFunctionData ndata : nestedFunctions.values()) { 987 data = ndata.getScriptFunctionData(functionId); 988 if (data != null) { 989 return data; 990 } 991 } 992 return null; 993 } 994 995 /** 996 * Check whether a certain name is a global symbol, i.e. only exists as defined 997 * in outermost scope and not shadowed by being parameter or assignment in inner 998 * scopes 999 * 1000 * @param functionNode function node to check 1001 * @param symbolName symbol name 1002 * @return true if global symbol 1003 */ 1004 public boolean isGlobalSymbol(final FunctionNode functionNode, final String symbolName) { 1005 RecompilableScriptFunctionData data = getScriptFunctionData(functionNode.getId()); 1006 assert data != null; 1007 1008 do { 1009 if (data.hasInternalSymbol(symbolName)) { 1010 return false; 1011 } 1012 data = data.getParent(); 1013 } while(data != null); 1014 1015 return true; 1016 } 1017 1018 /** 1019 * Restores the {@link #getFunctionFlags()} flags to a function node. During on-demand compilation, we might need 1020 * to restore flags to a function node that was otherwise not subjected to a full compile pipeline (e.g. its parse 1021 * was skipped, or it's a nested function of a deserialized function. 1022 * @param lc current lexical context 1023 * @param fn the function node to restore flags onto 1024 * @return the transformed function node 1025 */ 1026 public FunctionNode restoreFlags(final LexicalContext lc, final FunctionNode fn) { 1027 assert fn.getId() == functionNodeId; 1028 FunctionNode newFn = fn.setFlags(lc, functionFlags); 1029 // This compensates for missing markEval() in case the function contains an inner function 1030 // that contains eval(), that now we didn't discover since we skipped the inner function. 1031 if (newFn.hasNestedEval()) { 1032 assert newFn.hasScopeBlock(); 1033 newFn = newFn.setBody(lc, newFn.getBody().setNeedsScope(null)); 1034 } 1035 return newFn; 1036 } 1037 1038 // Make sure code does not contain a compiled function with the same signature as compiledFunction 1039 private boolean noDuplicateCode(final CompiledFunction compiledFunction) { 1040 for (final CompiledFunction cf : code) { 1041 if (cf.type().equals(compiledFunction.type())) { 1042 return false; 1043 } 1044 } 1045 return true; 1046 } 1047 1048 private void writeObject(final ObjectOutputStream out) throws IOException { 1049 final Object localCachedAst = cachedAst; 1050 out.defaultWriteObject(); 1051 // We need to persist SerializedAst for split functions as they can't reparse the source code. 1052 if (localCachedAst instanceof SerializedAst) { 1053 out.writeObject(localCachedAst); 1054 } else { 1055 out.writeObject(null); 1056 } 1057 } 1058 1059 private void readObject(final java.io.ObjectInputStream in) throws IOException, ClassNotFoundException { 1060 in.defaultReadObject(); 1061 cachedAst = in.readObject(); 1062 createLogger(); 1063 } 1064 1065 private void createLogger() { 1066 log = initLogger(Context.getContextTrusted()); 1067 } 1068} 1069