RecompilableScriptFunctionData.java revision 1256:b275aac76cdd
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; 29import java.io.IOException; 30import java.lang.invoke.MethodHandle; 31import java.lang.invoke.MethodHandles; 32import java.lang.invoke.MethodType; 33import java.util.Collection; 34import java.util.Collections; 35import java.util.HashSet; 36import java.util.Map; 37import java.util.Set; 38import java.util.TreeMap; 39import jdk.internal.dynalink.support.NameCodec; 40import jdk.nashorn.internal.codegen.Compiler; 41import jdk.nashorn.internal.codegen.Compiler.CompilationPhases; 42import jdk.nashorn.internal.codegen.CompilerConstants; 43import jdk.nashorn.internal.codegen.FunctionSignature; 44import jdk.nashorn.internal.codegen.Namespace; 45import jdk.nashorn.internal.codegen.OptimisticTypesPersistence; 46import jdk.nashorn.internal.codegen.TypeMap; 47import jdk.nashorn.internal.codegen.types.Type; 48import jdk.nashorn.internal.ir.FunctionNode; 49import jdk.nashorn.internal.ir.LexicalContext; 50import jdk.nashorn.internal.ir.visitor.NodeVisitor; 51import jdk.nashorn.internal.objects.Global; 52import jdk.nashorn.internal.parser.Parser; 53import jdk.nashorn.internal.parser.Token; 54import jdk.nashorn.internal.parser.TokenType; 55import jdk.nashorn.internal.runtime.logging.DebugLogger; 56import jdk.nashorn.internal.runtime.logging.Loggable; 57import jdk.nashorn.internal.runtime.logging.Logger; 58/** 59 * This is a subclass that represents a script function that may be regenerated, 60 * for example with specialization based on call site types, or lazily generated. 61 * The common denominator is that it can get new invokers during its lifespan, 62 * unlike {@code FinalScriptFunctionData} 63 */ 64@Logger(name="recompile") 65public final class RecompilableScriptFunctionData extends ScriptFunctionData implements Loggable { 66 /** Prefix used for all recompiled script classes */ 67 public static final String RECOMPILATION_PREFIX = "Recompilation$"; 68 69 /** Unique function node id for this function node */ 70 private final int functionNodeId; 71 72 private final String functionName; 73 74 /** The line number where this function begins. */ 75 private final int lineNumber; 76 77 /** Source from which FunctionNode was parsed. */ 78 private transient Source source; 79 80 /** Serialized, compressed form of the AST. Used by split functions as they can't be reparsed from source. */ 81 private final byte[] serializedAst; 82 83 /** Token of this function within the source. */ 84 private final long token; 85 86 /** 87 * Represents the allocation strategy (property map, script object class, and method handle) for when 88 * this function is used as a constructor. Note that majority of functions (those not setting any this.* 89 * properties) will share a single canonical "default strategy" instance. 90 */ 91 private final AllocationStrategy allocationStrategy; 92 93 /** 94 * Opaque object representing parser state at the end of the function. Used when reparsing outer function 95 * to help with skipping parsing inner functions. 96 */ 97 private final Object endParserState; 98 99 /** Code installer used for all further recompilation/specialization of this ScriptFunction */ 100 private transient CodeInstaller<ScriptEnvironment> installer; 101 102 private final Map<Integer, RecompilableScriptFunctionData> nestedFunctions; 103 104 /** Id to parent function if one exists */ 105 private RecompilableScriptFunctionData parent; 106 107 /** Copy of the {@link FunctionNode} flags. */ 108 private final int functionFlags; 109 110 private static final MethodHandles.Lookup LOOKUP = MethodHandles.lookup(); 111 112 private transient DebugLogger log; 113 114 private final Map<String, Integer> externalScopeDepths; 115 116 private final Set<String> internalSymbols; 117 118 private static final int GET_SET_PREFIX_LENGTH = "*et ".length(); 119 120 private static final long serialVersionUID = 4914839316174633726L; 121 122 /** 123 * Constructor - public as scripts use it 124 * 125 * @param functionNode functionNode that represents this function code 126 * @param installer installer for code regeneration versions of this function 127 * @param allocationStrategy strategy for the allocation behavior when this function is used as a constructor 128 * @param nestedFunctions nested function map 129 * @param externalScopeDepths external scope depths 130 * @param internalSymbols internal symbols to method, defined in its scope 131 * @param serializedAst a serialized AST representation. Normally only used for split functions. 132 */ 133 public RecompilableScriptFunctionData( 134 final FunctionNode functionNode, 135 final CodeInstaller<ScriptEnvironment> installer, 136 final AllocationStrategy allocationStrategy, 137 final Map<Integer, RecompilableScriptFunctionData> nestedFunctions, 138 final Map<String, Integer> externalScopeDepths, 139 final Set<String> internalSymbols, 140 final byte[] serializedAst) { 141 142 super(functionName(functionNode), 143 Math.min(functionNode.getParameters().size(), MAX_ARITY), 144 getDataFlags(functionNode)); 145 146 this.functionName = functionNode.getName(); 147 this.lineNumber = functionNode.getLineNumber(); 148 this.functionFlags = functionNode.getFlags() | (functionNode.needsCallee() ? FunctionNode.NEEDS_CALLEE : 0); 149 this.functionNodeId = functionNode.getId(); 150 this.source = functionNode.getSource(); 151 this.endParserState = functionNode.getEndParserState(); 152 this.token = tokenFor(functionNode); 153 this.installer = installer; 154 this.allocationStrategy = allocationStrategy; 155 this.nestedFunctions = smallMap(nestedFunctions); 156 this.externalScopeDepths = smallMap(externalScopeDepths); 157 this.internalSymbols = smallSet(new HashSet<>(internalSymbols)); 158 159 for (final RecompilableScriptFunctionData nfn : nestedFunctions.values()) { 160 assert nfn.getParent() == null; 161 nfn.setParent(this); 162 } 163 164 this.serializedAst = serializedAst; 165 createLogger(); 166 } 167 168 private static <K, V> Map<K, V> smallMap(final Map<K, V> map) { 169 if (map == null || map.isEmpty()) { 170 return Collections.emptyMap(); 171 } else if (map.size() == 1) { 172 final Map.Entry<K, V> entry = map.entrySet().iterator().next(); 173 return Collections.singletonMap(entry.getKey(), entry.getValue()); 174 } else { 175 return map; 176 } 177 } 178 179 private static <T> Set<T> smallSet(final Set<T> set) { 180 if (set == null || set.isEmpty()) { 181 return Collections.emptySet(); 182 } else if (set.size() == 1) { 183 return Collections.singleton(set.iterator().next()); 184 } else { 185 return set; 186 } 187 } 188 189 @Override 190 public DebugLogger getLogger() { 191 return log; 192 } 193 194 @Override 195 public DebugLogger initLogger(final Context ctxt) { 196 return ctxt.getLogger(this.getClass()); 197 } 198 199 /** 200 * Check if a symbol is internally defined in a function. For example 201 * if "undefined" is internally defined in the outermost program function, 202 * it has not been reassigned or overridden and can be optimized 203 * 204 * @param symbolName symbol name 205 * @return true if symbol is internal to this ScriptFunction 206 */ 207 208 public boolean hasInternalSymbol(final String symbolName) { 209 return internalSymbols.contains(symbolName); 210 } 211 212 /** 213 * Return the external symbol table 214 * @param symbolName symbol name 215 * @return the external symbol table with proto depths 216 */ 217 public int getExternalSymbolDepth(final String symbolName) { 218 final Integer depth = externalScopeDepths.get(symbolName); 219 return depth == null ? -1 : depth; 220 } 221 222 /** 223 * Returns the names of all external symbols this function uses. 224 * @return the names of all external symbols this function uses. 225 */ 226 public Set<String> getExternalSymbolNames() { 227 return Collections.unmodifiableSet(externalScopeDepths.keySet()); 228 } 229 230 /** 231 * Returns the opaque object representing the parser state at the end of this function's body, used to 232 * skip parsing this function when reparsing its containing outer function. 233 * @return the object representing the end parser state 234 */ 235 public Object getEndParserState() { 236 return endParserState; 237 } 238 239 /** 240 * Get the parent of this RecompilableScriptFunctionData. If we are 241 * a nested function, we have a parent. Note that "null" return value 242 * can also mean that we have a parent but it is unknown, so this can 243 * only be used for conservative assumptions. 244 * @return parent data, or null if non exists and also null IF UNKNOWN. 245 */ 246 public RecompilableScriptFunctionData getParent() { 247 return parent; 248 } 249 250 void setParent(final RecompilableScriptFunctionData parent) { 251 this.parent = parent; 252 } 253 254 @Override 255 String toSource() { 256 if (source != null && token != 0) { 257 return source.getString(Token.descPosition(token), Token.descLength(token)); 258 } 259 260 return "function " + (name == null ? "" : name) + "() { [native code] }"; 261 } 262 263 /** 264 * Initialize transient fields on deserialized instances 265 * 266 * @param src source 267 * @param inst code installer 268 */ 269 public void initTransients(final Source src, final CodeInstaller<ScriptEnvironment> inst) { 270 if (this.source == null && this.installer == null) { 271 this.source = src; 272 this.installer = inst; 273 } else if (this.source != src || !this.installer.isCompatibleWith(inst)) { 274 // Existing values must be same as those passed as parameters 275 throw new IllegalArgumentException(); 276 } 277 } 278 279 @Override 280 public String toString() { 281 return super.toString() + '@' + functionNodeId; 282 } 283 284 @Override 285 public String toStringVerbose() { 286 final StringBuilder sb = new StringBuilder(); 287 288 sb.append("fnId=").append(functionNodeId).append(' '); 289 290 if (source != null) { 291 sb.append(source.getName()) 292 .append(':') 293 .append(lineNumber) 294 .append(' '); 295 } 296 297 return sb.toString() + super.toString(); 298 } 299 300 @Override 301 public String getFunctionName() { 302 return functionName; 303 } 304 305 @Override 306 public boolean inDynamicContext() { 307 return getFunctionFlag(FunctionNode.IN_DYNAMIC_CONTEXT); 308 } 309 310 private static String functionName(final FunctionNode fn) { 311 if (fn.isAnonymous()) { 312 return ""; 313 } 314 final FunctionNode.Kind kind = fn.getKind(); 315 if (kind == FunctionNode.Kind.GETTER || kind == FunctionNode.Kind.SETTER) { 316 final String name = NameCodec.decode(fn.getIdent().getName()); 317 return name.substring(GET_SET_PREFIX_LENGTH); 318 } 319 return fn.getIdent().getName(); 320 } 321 322 private static long tokenFor(final FunctionNode fn) { 323 final int position = Token.descPosition(fn.getFirstToken()); 324 final long lastToken = Token.withDelimiter(fn.getLastToken()); 325 // EOL uses length field to store the line number 326 final int length = Token.descPosition(lastToken) - position + (Token.descType(lastToken) == TokenType.EOL ? 0 : Token.descLength(lastToken)); 327 328 return Token.toDesc(TokenType.FUNCTION, position, length); 329 } 330 331 private static int getDataFlags(final FunctionNode functionNode) { 332 int flags = IS_CONSTRUCTOR; 333 if (functionNode.isStrict()) { 334 flags |= IS_STRICT; 335 } 336 if (functionNode.needsCallee()) { 337 flags |= NEEDS_CALLEE; 338 } 339 if (functionNode.usesThis() || functionNode.hasEval()) { 340 flags |= USES_THIS; 341 } 342 if (functionNode.isVarArg()) { 343 flags |= IS_VARIABLE_ARITY; 344 } 345 return flags; 346 } 347 348 @Override 349 PropertyMap getAllocatorMap() { 350 return allocationStrategy.getAllocatorMap(); 351 } 352 353 @Override 354 ScriptObject allocate(final PropertyMap map) { 355 return allocationStrategy.allocate(map); 356 } 357 358 boolean isSerialized() { 359 return serializedAst != null; 360 } 361 362 FunctionNode reparse() { 363 if (isSerialized()) { 364 return deserialize(); 365 } 366 367 final int descPosition = Token.descPosition(token); 368 final Context context = Context.getContextTrusted(); 369 final Parser parser = new Parser( 370 context.getEnv(), 371 source, 372 new Context.ThrowErrorManager(), 373 isStrict(), 374 // source starts at line 0, so even though lineNumber is the correct declaration line, back off 375 // one to make it exclusive 376 lineNumber - 1, 377 context.getLogger(Parser.class)); 378 379 if (getFunctionFlag(FunctionNode.IS_ANONYMOUS)) { 380 parser.setFunctionName(functionName); 381 } 382 parser.setReparsedFunction(this); 383 384 final FunctionNode program = parser.parse(CompilerConstants.PROGRAM.symbolName(), descPosition, 385 Token.descLength(token), true); 386 // Parser generates a program AST even if we're recompiling a single function, so when we are only 387 // recompiling a single function, extract it from the program. 388 return (isProgram() ? program : extractFunctionFromScript(program)).setName(null, functionName); 389 } 390 391 private FunctionNode deserialize() { 392 final ScriptEnvironment env = installer.getOwner(); 393 final Timing timing = env._timing; 394 final long t1 = System.nanoTime(); 395 try { 396 return AstDeserializer.deserialize(serializedAst).initializeDeserialized(source, new Namespace(env.getNamespace())); 397 } finally { 398 timing.accumulateTime("'Deserialize'", System.nanoTime() - t1); 399 } 400 } 401 402 private boolean getFunctionFlag(final int flag) { 403 return (functionFlags & flag) != 0; 404 } 405 406 private boolean isProgram() { 407 return getFunctionFlag(FunctionNode.IS_PROGRAM); 408 } 409 410 TypeMap typeMap(final MethodType fnCallSiteType) { 411 if (fnCallSiteType == null) { 412 return null; 413 } 414 415 if (CompiledFunction.isVarArgsType(fnCallSiteType)) { 416 return null; 417 } 418 419 return new TypeMap(functionNodeId, explicitParams(fnCallSiteType), needsCallee()); 420 } 421 422 private static ScriptObject newLocals(final ScriptObject runtimeScope) { 423 final ScriptObject locals = Global.newEmptyInstance(); 424 locals.setProto(runtimeScope); 425 return locals; 426 } 427 428 private Compiler getCompiler(final FunctionNode fn, final MethodType actualCallSiteType, final ScriptObject runtimeScope) { 429 return getCompiler(fn, actualCallSiteType, newLocals(runtimeScope), null, null); 430 } 431 432 /** 433 * Returns a code installer for installing new code. If we're using either optimistic typing or loader-per-compile, 434 * then asks for a code installer with a new class loader; otherwise just uses the current installer. We use 435 * a new class loader with optimistic typing so that deoptimized code can get reclaimed by GC. 436 * @return a code installer for installing new code. 437 */ 438 private CodeInstaller<ScriptEnvironment> getInstallerForNewCode() { 439 final ScriptEnvironment env = installer.getOwner(); 440 return env._optimistic_types || env._loader_per_compile ? installer.withNewLoader() : installer; 441 } 442 443 Compiler getCompiler(final FunctionNode functionNode, final MethodType actualCallSiteType, 444 final ScriptObject runtimeScope, final Map<Integer, Type> invalidatedProgramPoints, 445 final int[] continuationEntryPoints) { 446 final TypeMap typeMap = typeMap(actualCallSiteType); 447 final Type[] paramTypes = typeMap == null ? null : typeMap.getParameterTypes(functionNodeId); 448 final Object typeInformationFile = OptimisticTypesPersistence.getLocationDescriptor(source, functionNodeId, paramTypes); 449 final Context context = Context.getContextTrusted(); 450 return new Compiler( 451 context, 452 context.getEnv(), 453 getInstallerForNewCode(), 454 functionNode.getSource(), // source 455 context.getErrorManager(), 456 isStrict() | functionNode.isStrict(), // is strict 457 true, // is on demand 458 this, // compiledFunction, i.e. this RecompilableScriptFunctionData 459 typeMap, // type map 460 getEffectiveInvalidatedProgramPoints(invalidatedProgramPoints, typeInformationFile), // invalidated program points 461 typeInformationFile, 462 continuationEntryPoints, // continuation entry points 463 runtimeScope); // runtime scope 464 } 465 466 /** 467 * If the function being compiled already has its own invalidated program points map, use it. Otherwise, attempt to 468 * load invalidated program points map from the persistent type info cache. 469 * @param invalidatedProgramPoints the function's current invalidated program points map. Null if the function 470 * doesn't have it. 471 * @param typeInformationFile the object describing the location of the persisted type information. 472 * @return either the existing map, or a loaded map from the persistent type info cache, or a new empty map if 473 * neither an existing map or a persistent cached type info is available. 474 */ 475 @SuppressWarnings("unused") 476 private static Map<Integer, Type> getEffectiveInvalidatedProgramPoints( 477 final Map<Integer, Type> invalidatedProgramPoints, final Object typeInformationFile) { 478 if(invalidatedProgramPoints != null) { 479 return invalidatedProgramPoints; 480 } 481 final Map<Integer, Type> loadedProgramPoints = OptimisticTypesPersistence.load(typeInformationFile); 482 return loadedProgramPoints != null ? loadedProgramPoints : new TreeMap<Integer, Type>(); 483 } 484 485 private FunctionInitializer compileTypeSpecialization(final MethodType actualCallSiteType, final ScriptObject runtimeScope, final boolean persist) { 486 // We're creating an empty script object for holding local variables. AssignSymbols will populate it with 487 // explicit Undefined values for undefined local variables (see AssignSymbols#defineSymbol() and 488 // CompilationEnvironment#declareLocalSymbol()). 489 490 if (log.isEnabled()) { 491 log.info("Parameter type specialization of '", functionName, "' signature: ", actualCallSiteType); 492 } 493 494 final boolean persistentCache = usePersistentCodeCache() && persist; 495 String cacheKey = null; 496 if (persistentCache) { 497 final TypeMap typeMap = typeMap(actualCallSiteType); 498 final Type[] paramTypes = typeMap == null ? null : typeMap.getParameterTypes(functionNodeId); 499 cacheKey = CodeStore.getCacheKey(functionNodeId, paramTypes); 500 final CodeInstaller<ScriptEnvironment> newInstaller = getInstallerForNewCode(); 501 final StoredScript script = newInstaller.loadScript(source, cacheKey); 502 503 if (script != null) { 504 Compiler.updateCompilationId(script.getCompilationId()); 505 return script.installFunction(this, newInstaller); 506 } 507 } 508 509 final FunctionNode fn = reparse(); 510 final Compiler compiler = getCompiler(fn, actualCallSiteType, runtimeScope); 511 final FunctionNode compiledFn = compiler.compile(fn, 512 isSerialized() ? CompilationPhases.COMPILE_ALL_SERIALIZED : CompilationPhases.COMPILE_ALL); 513 514 if (persist && !compiledFn.getFlag(FunctionNode.HAS_APPLY_TO_CALL_SPECIALIZATION)) { 515 compiler.persistClassInfo(cacheKey, compiledFn); 516 } 517 return new FunctionInitializer(compiledFn, compiler.getInvalidatedProgramPoints()); 518 } 519 520 boolean usePersistentCodeCache() { 521 final ScriptEnvironment env = installer.getOwner(); 522 return env._persistent_cache && env._optimistic_types; 523 } 524 525 private MethodType explicitParams(final MethodType callSiteType) { 526 if (CompiledFunction.isVarArgsType(callSiteType)) { 527 return null; 528 } 529 530 final MethodType noCalleeThisType = callSiteType.dropParameterTypes(0, 2); // (callee, this) is always in call site type 531 final int callSiteParamCount = noCalleeThisType.parameterCount(); 532 533 // Widen parameters of reference types to Object as we currently don't care for specialization among reference 534 // types. E.g. call site saying (ScriptFunction, Object, String) should still link to (ScriptFunction, Object, Object) 535 final Class<?>[] paramTypes = noCalleeThisType.parameterArray(); 536 boolean changed = false; 537 for (int i = 0; i < paramTypes.length; ++i) { 538 final Class<?> paramType = paramTypes[i]; 539 if (!(paramType.isPrimitive() || paramType == Object.class)) { 540 paramTypes[i] = Object.class; 541 changed = true; 542 } 543 } 544 final MethodType generalized = changed ? MethodType.methodType(noCalleeThisType.returnType(), paramTypes) : noCalleeThisType; 545 546 if (callSiteParamCount < getArity()) { 547 return generalized.appendParameterTypes(Collections.<Class<?>>nCopies(getArity() - callSiteParamCount, Object.class)); 548 } 549 return generalized; 550 } 551 552 private FunctionNode extractFunctionFromScript(final FunctionNode script) { 553 final Set<FunctionNode> fns = new HashSet<>(); 554 script.getBody().accept(new NodeVisitor<LexicalContext>(new LexicalContext()) { 555 @Override 556 public boolean enterFunctionNode(final FunctionNode fn) { 557 fns.add(fn); 558 return false; 559 } 560 }); 561 assert fns.size() == 1 : "got back more than one method in recompilation"; 562 final FunctionNode f = fns.iterator().next(); 563 assert f.getId() == functionNodeId; 564 if (!getFunctionFlag(FunctionNode.IS_DECLARED) && f.isDeclared()) { 565 return f.clearFlag(null, FunctionNode.IS_DECLARED); 566 } 567 return f; 568 } 569 570 private void logLookup(final boolean shouldLog, final MethodType targetType) { 571 if (shouldLog && log.isEnabled()) { 572 log.info("Looking up ", DebugLogger.quote(functionName), " type=", targetType); 573 } 574 } 575 576 private MethodHandle lookup(final FunctionInitializer fnInit, final boolean shouldLog) { 577 final MethodType type = fnInit.getMethodType(); 578 logLookup(shouldLog, type); 579 return lookupCodeMethod(fnInit.getCode(), type); 580 } 581 582 MethodHandle lookup(final FunctionNode fn) { 583 final MethodType type = new FunctionSignature(fn).getMethodType(); 584 logLookup(true, type); 585 return lookupCodeMethod(fn.getCompileUnit().getCode(), type); 586 } 587 588 MethodHandle lookupCodeMethod(final Class<?> codeClass, final MethodType targetType) { 589 return MH.findStatic(LOOKUP, codeClass, functionName, targetType); 590 } 591 592 /** 593 * Initializes this function data with the eagerly generated version of the code. This method can only be invoked 594 * by the compiler internals in Nashorn and is public for implementation reasons only. Attempting to invoke it 595 * externally will result in an exception. 596 * 597 * @param functionNode FunctionNode for this data 598 */ 599 public void initializeCode(final FunctionNode functionNode) { 600 // Since the method is public, we double-check that we aren't invoked with an inappropriate compile unit. 601 if (!code.isEmpty() || functionNode.getId() != functionNodeId || !functionNode.getCompileUnit().isInitializing(this, functionNode)) { 602 throw new IllegalStateException(name); 603 } 604 addCode(lookup(functionNode), null, null, functionNode.getFlags()); 605 } 606 607 /** 608 * Initializes this function with the given function code initializer. 609 * @param initializer function code initializer 610 */ 611 void initializeCode(final FunctionInitializer initializer) { 612 addCode(lookup(initializer, true), null, null, initializer.getFlags()); 613 } 614 615 private CompiledFunction addCode(final MethodHandle target, final Map<Integer, Type> invalidatedProgramPoints, 616 final MethodType callSiteType, final int fnFlags) { 617 final CompiledFunction cfn = new CompiledFunction(target, this, invalidatedProgramPoints, callSiteType, fnFlags); 618 code.add(cfn); 619 return cfn; 620 } 621 622 /** 623 * Add code with specific call site type. It will adapt the type of the looked up method handle to fit the call site 624 * type. This is necessary because even if we request a specialization that takes an "int" parameter, we might end 625 * up getting one that takes a "double" etc. because of internal function logic causes widening (e.g. assignment of 626 * a wider value to the parameter variable). However, we use the method handle type for matching subsequent lookups 627 * for the same specialization, so we must adapt the handle to the expected type. 628 * @param fnInit the function 629 * @param callSiteType the call site type 630 * @return the compiled function object, with its type matching that of the call site type. 631 */ 632 private CompiledFunction addCode(final FunctionInitializer fnInit, final MethodType callSiteType) { 633 if (isVariableArity()) { 634 return addCode(lookup(fnInit, true), fnInit.getInvalidatedProgramPoints(), callSiteType, fnInit.getFlags()); 635 } 636 637 final MethodHandle handle = lookup(fnInit, true); 638 final MethodType fromType = handle.type(); 639 MethodType toType = needsCallee(fromType) ? callSiteType.changeParameterType(0, ScriptFunction.class) : callSiteType.dropParameterTypes(0, 1); 640 toType = toType.changeReturnType(fromType.returnType()); 641 642 final int toCount = toType.parameterCount(); 643 final int fromCount = fromType.parameterCount(); 644 final int minCount = Math.min(fromCount, toCount); 645 for(int i = 0; i < minCount; ++i) { 646 final Class<?> fromParam = fromType.parameterType(i); 647 final Class<?> toParam = toType.parameterType(i); 648 // If method has an Object parameter, but call site had String, preserve it as Object. No need to narrow it 649 // artificially. Note that this is related to how CompiledFunction.matchesCallSite() works, specifically 650 // the fact that various reference types compare to equal (see "fnType.isEquivalentTo(csType)" there). 651 if (fromParam != toParam && !fromParam.isPrimitive() && !toParam.isPrimitive()) { 652 assert fromParam.isAssignableFrom(toParam); 653 toType = toType.changeParameterType(i, fromParam); 654 } 655 } 656 if (fromCount > toCount) { 657 toType = toType.appendParameterTypes(fromType.parameterList().subList(toCount, fromCount)); 658 } else if (fromCount < toCount) { 659 toType = toType.dropParameterTypes(fromCount, toCount); 660 } 661 662 return addCode(lookup(fnInit, false).asType(toType), fnInit.getInvalidatedProgramPoints(), callSiteType, fnInit.getFlags()); 663 } 664 665 /** 666 * Returns the return type of a function specialization for particular parameter types.<br> 667 * <b>Be aware that the way this is implemented, it forces full materialization (compilation and installation) of 668 * code for that specialization.</b> 669 * @param callSiteType the parameter types at the call site. It must include the mandatory {@code callee} and 670 * {@code this} parameters, so it needs to start with at least {@code ScriptFunction.class} and 671 * {@code Object.class} class. Since the return type of the function is calculated from the code itself, it is 672 * irrelevant and should be set to {@code Object.class}. 673 * @param runtimeScope a current runtime scope. Can be null but when it's present it will be used as a source of 674 * current runtime values that can improve the compiler's type speculations (and thus reduce the need for later 675 * recompilations) if the specialization is not already present and thus needs to be freshly compiled. 676 * @return the return type of the function specialization. 677 */ 678 public Class<?> getReturnType(final MethodType callSiteType, final ScriptObject runtimeScope) { 679 return getBest(callSiteType, runtimeScope, CompiledFunction.NO_FUNCTIONS).type().returnType(); 680 } 681 682 @Override 683 synchronized CompiledFunction getBest(final MethodType callSiteType, final ScriptObject runtimeScope, final Collection<CompiledFunction> forbidden) { 684 CompiledFunction existingBest = super.getBest(callSiteType, runtimeScope, forbidden); 685 if (existingBest == null) { 686 existingBest = addCode(compileTypeSpecialization(callSiteType, runtimeScope, true), callSiteType); 687 } 688 689 assert existingBest != null; 690 //we are calling a vararg method with real args 691 boolean varArgWithRealArgs = existingBest.isVarArg() && !CompiledFunction.isVarArgsType(callSiteType); 692 693 //if the best one is an apply to call, it has to match the callsite exactly 694 //or we need to regenerate 695 if (existingBest.isApplyToCall()) { 696 final CompiledFunction best = lookupExactApplyToCall(callSiteType); 697 if (best != null) { 698 return best; 699 } 700 varArgWithRealArgs = true; 701 } 702 703 if (varArgWithRealArgs) { 704 // special case: we had an apply to call, but we failed to make it fit. 705 // Try to generate a specialized one for this callsite. It may 706 // be another apply to call specialization, or it may not, but whatever 707 // it is, it is a specialization that is guaranteed to fit 708 final FunctionInitializer fnInit = compileTypeSpecialization(callSiteType, runtimeScope, false); 709 existingBest = addCode(fnInit, callSiteType); 710 } 711 712 return existingBest; 713 } 714 715 @Override 716 boolean isRecompilable() { 717 return true; 718 } 719 720 @Override 721 public boolean needsCallee() { 722 return getFunctionFlag(FunctionNode.NEEDS_CALLEE); 723 } 724 725 /** 726 * Returns the {@link FunctionNode} flags associated with this function data. 727 * @return the {@link FunctionNode} flags associated with this function data. 728 */ 729 public int getFunctionFlags() { 730 return functionFlags; 731 } 732 733 @Override 734 MethodType getGenericType() { 735 // 2 is for (callee, this) 736 if (isVariableArity()) { 737 return MethodType.genericMethodType(2, true); 738 } 739 return MethodType.genericMethodType(2 + getArity()); 740 } 741 742 /** 743 * Return the function node id. 744 * @return the function node id 745 */ 746 public int getFunctionNodeId() { 747 return functionNodeId; 748 } 749 750 /** 751 * Get the source for the script 752 * @return source 753 */ 754 public Source getSource() { 755 return source; 756 } 757 758 /** 759 * Return a script function data based on a function id, either this function if 760 * the id matches or a nested function based on functionId. This goes down into 761 * nested functions until all leaves are exhausted. 762 * 763 * @param functionId function id 764 * @return script function data or null if invalid id 765 */ 766 public RecompilableScriptFunctionData getScriptFunctionData(final int functionId) { 767 if (functionId == functionNodeId) { 768 return this; 769 } 770 RecompilableScriptFunctionData data; 771 772 data = nestedFunctions == null ? null : nestedFunctions.get(functionId); 773 if (data != null) { 774 return data; 775 } 776 for (final RecompilableScriptFunctionData ndata : nestedFunctions.values()) { 777 data = ndata.getScriptFunctionData(functionId); 778 if (data != null) { 779 return data; 780 } 781 } 782 return null; 783 } 784 785 /** 786 * Check whether a certain name is a global symbol, i.e. only exists as defined 787 * in outermost scope and not shadowed by being parameter or assignment in inner 788 * scopes 789 * 790 * @param functionNode function node to check 791 * @param symbolName symbol name 792 * @return true if global symbol 793 */ 794 public boolean isGlobalSymbol(final FunctionNode functionNode, final String symbolName) { 795 RecompilableScriptFunctionData data = getScriptFunctionData(functionNode.getId()); 796 assert data != null; 797 798 do { 799 if (data.hasInternalSymbol(symbolName)) { 800 return false; 801 } 802 data = data.getParent(); 803 } while(data != null); 804 805 return true; 806 } 807 808 /** 809 * Restores the {@link #getFunctionFlags()} flags to a function node. During on-demand compilation, we might need 810 * to restore flags to a function node that was otherwise not subjected to a full compile pipeline (e.g. its parse 811 * was skipped, or it's a nested function of a deserialized function. 812 * @param lc current lexical context 813 * @param fn the function node to restore flags onto 814 * @return the transformed function node 815 */ 816 public FunctionNode restoreFlags(final LexicalContext lc, final FunctionNode fn) { 817 assert fn.getId() == functionNodeId; 818 FunctionNode newFn = fn.setFlags(lc, functionFlags); 819 // This compensates for missing markEval() in case the function contains an inner function 820 // that contains eval(), that now we didn't discover since we skipped the inner function. 821 if (newFn.hasNestedEval()) { 822 assert newFn.hasScopeBlock(); 823 newFn = newFn.setBody(lc, newFn.getBody().setNeedsScope(null)); 824 } 825 return newFn; 826 } 827 828 private void readObject(final java.io.ObjectInputStream in) throws IOException, ClassNotFoundException { 829 in.defaultReadObject(); 830 createLogger(); 831 } 832 833 private void createLogger() { 834 log = initLogger(Context.getContextTrusted()); 835 } 836} 837