ScriptFunction.java revision 953:221a84ef44c0
1/* 2 * Copyright (c) 2010, 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 26package jdk.nashorn.internal.runtime; 27 28import static jdk.nashorn.internal.codegen.CompilerConstants.virtualCallNoLookup; 29import static jdk.nashorn.internal.lookup.Lookup.MH; 30import static jdk.nashorn.internal.runtime.ECMAErrors.typeError; 31import static jdk.nashorn.internal.runtime.ScriptRuntime.UNDEFINED; 32import static jdk.nashorn.internal.runtime.UnwarrantedOptimismException.INVALID_PROGRAM_POINT; 33 34import java.lang.invoke.MethodHandle; 35import java.lang.invoke.MethodHandles; 36import java.lang.invoke.MethodType; 37import java.lang.invoke.SwitchPoint; 38import java.util.Collections; 39import jdk.internal.dynalink.CallSiteDescriptor; 40import jdk.internal.dynalink.linker.GuardedInvocation; 41import jdk.internal.dynalink.linker.LinkRequest; 42import jdk.internal.dynalink.support.Guards; 43import jdk.nashorn.internal.codegen.ApplySpecialization; 44import jdk.nashorn.internal.codegen.CompilerConstants.Call; 45import jdk.nashorn.internal.objects.Global; 46import jdk.nashorn.internal.objects.NativeFunction; 47import jdk.nashorn.internal.runtime.linker.Bootstrap; 48import jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor; 49 50/** 51 * Runtime representation of a JavaScript function. 52 */ 53public abstract class ScriptFunction extends ScriptObject { 54 55 /** Method handle for prototype getter for this ScriptFunction */ 56 public static final MethodHandle G$PROTOTYPE = findOwnMH_S("G$prototype", Object.class, Object.class); 57 58 /** Method handle for prototype setter for this ScriptFunction */ 59 public static final MethodHandle S$PROTOTYPE = findOwnMH_S("S$prototype", void.class, Object.class, Object.class); 60 61 /** Method handle for length getter for this ScriptFunction */ 62 public static final MethodHandle G$LENGTH = findOwnMH_S("G$length", int.class, Object.class); 63 64 /** Method handle for name getter for this ScriptFunction */ 65 public static final MethodHandle G$NAME = findOwnMH_S("G$name", Object.class, Object.class); 66 67 /** Method handle used for implementing sync() in mozilla_compat */ 68 public static final MethodHandle INVOKE_SYNC = findOwnMH_S("invokeSync", Object.class, ScriptFunction.class, Object.class, Object.class, Object[].class); 69 70 /** Method handle for allocate function for this ScriptFunction */ 71 static final MethodHandle ALLOCATE = findOwnMH_V("allocate", Object.class); 72 73 private static final MethodHandle WRAPFILTER = findOwnMH_S("wrapFilter", Object.class, Object.class); 74 75 private static final MethodHandle SCRIPTFUNCTION_GLOBALFILTER = findOwnMH_S("globalFilter", Object.class, Object.class); 76 77 /** method handle to scope getter for this ScriptFunction */ 78 public static final Call GET_SCOPE = virtualCallNoLookup(ScriptFunction.class, "getScope", ScriptObject.class); 79 80 private static final MethodHandle IS_FUNCTION_MH = findOwnMH_S("isFunctionMH", boolean.class, Object.class, ScriptFunctionData.class); 81 82 private static final MethodHandle IS_APPLY_FUNCTION = findOwnMH_S("isApplyFunction", boolean.class, boolean.class, Object.class, Object.class); 83 84 private static final MethodHandle IS_NONSTRICT_FUNCTION = findOwnMH_S("isNonStrictFunction", boolean.class, Object.class, Object.class, ScriptFunctionData.class); 85 86 private static final MethodHandle ADD_ZEROTH_ELEMENT = findOwnMH_S("addZerothElement", Object[].class, Object[].class, Object.class); 87 88 private static final MethodHandle WRAP_THIS = MH.findStatic(MethodHandles.lookup(), ScriptFunctionData.class, "wrapThis", MH.type(Object.class, Object.class)); 89 90 /** The parent scope. */ 91 private final ScriptObject scope; 92 93 private final ScriptFunctionData data; 94 95 /** The property map used for newly allocated object when function is used as constructor. */ 96 protected PropertyMap allocatorMap; 97 98 /** 99 * Constructor 100 * 101 * @param name function name 102 * @param methodHandle method handle to function (if specializations are present, assumed to be most generic) 103 * @param map property map 104 * @param scope scope 105 * @param specs specialized version of this function - other method handles 106 * @param flags {@link ScriptFunctionData} flags 107 */ 108 protected ScriptFunction( 109 final String name, 110 final MethodHandle methodHandle, 111 final PropertyMap map, 112 final ScriptObject scope, 113 final MethodHandle[] specs, 114 final int flags) { 115 116 this(new FinalScriptFunctionData(name, methodHandle, specs, flags), map, scope); 117 } 118 119 /** 120 * Constructor 121 * 122 * @param data static function data 123 * @param map property map 124 * @param scope scope 125 */ 126 protected ScriptFunction( 127 final ScriptFunctionData data, 128 final PropertyMap map, 129 final ScriptObject scope) { 130 131 super(map); 132 133 if (Context.DEBUG) { 134 constructorCount++; 135 } 136 137 this.data = data; 138 this.scope = scope; 139 this.allocatorMap = data.getAllocatorMap(); 140 } 141 142 @Override 143 public String getClassName() { 144 return "Function"; 145 } 146 147 /** 148 * ECMA 15.3.5.3 [[HasInstance]] (V) 149 * Step 3 if "prototype" value is not an Object, throw TypeError 150 */ 151 @Override 152 public boolean isInstance(final ScriptObject instance) { 153 final Object basePrototype = getTargetFunction().getPrototype(); 154 if (!(basePrototype instanceof ScriptObject)) { 155 throw typeError("prototype.not.an.object", ScriptRuntime.safeToString(getTargetFunction()), ScriptRuntime.safeToString(basePrototype)); 156 } 157 158 for (ScriptObject proto = instance.getProto(); proto != null; proto = proto.getProto()) { 159 if (proto == basePrototype) { 160 return true; 161 } 162 } 163 164 return false; 165 } 166 167 /** 168 * Returns the target function for this function. If the function was not created using 169 * {@link #makeBoundFunction(Object, Object[])}, its target function is itself. If it is bound, its target function 170 * is the target function of the function it was made from (therefore, the target function is always the final, 171 * unbound recipient of the calls). 172 * @return the target function for this function. 173 */ 174 protected ScriptFunction getTargetFunction() { 175 return this; 176 } 177 178 boolean isBoundFunction() { 179 return getTargetFunction() != this; 180 } 181 182 /** 183 * Set the arity of this ScriptFunction 184 * @param arity arity 185 */ 186 public final void setArity(final int arity) { 187 data.setArity(arity); 188 } 189 190 /** 191 * Is this a ECMAScript 'use strict' function? 192 * @return true if function is in strict mode 193 */ 194 public boolean isStrict() { 195 return data.isStrict(); 196 } 197 198 /** 199 * Returns true if this is a non-strict, non-built-in function that requires non-primitive this argument 200 * according to ECMA 10.4.3. 201 * @return true if this argument must be an object 202 */ 203 public boolean needsWrappedThis() { 204 return data.needsWrappedThis(); 205 } 206 207 private static boolean needsWrappedThis(final Object fn) { 208 return fn instanceof ScriptFunction ? ((ScriptFunction)fn).needsWrappedThis() : false; 209 } 210 211 /** 212 * Execute this script function. 213 * @param self Target object. 214 * @param arguments Call arguments. 215 * @return ScriptFunction result. 216 * @throws Throwable if there is an exception/error with the invocation or thrown from it 217 */ 218 Object invoke(final Object self, final Object... arguments) throws Throwable { 219 if (Context.DEBUG) { 220 invokes++; 221 } 222 return data.invoke(this, self, arguments); 223 } 224 225 /** 226 * Execute this script function as a constructor. 227 * @param arguments Call arguments. 228 * @return Newly constructed result. 229 * @throws Throwable if there is an exception/error with the invocation or thrown from it 230 */ 231 Object construct(final Object... arguments) throws Throwable { 232 return data.construct(this, arguments); 233 } 234 235 /** 236 * Allocate function. Called from generated {@link ScriptObject} code 237 * for allocation as a factory method 238 * 239 * @return a new instance of the {@link ScriptObject} whose allocator this is 240 */ 241 @SuppressWarnings("unused") 242 private Object allocate() { 243 if (Context.DEBUG) { 244 allocations++; 245 } 246 247 assert !isBoundFunction(); // allocate never invoked on bound functions 248 249 final ScriptObject object = data.allocate(allocatorMap); 250 251 if (object != null) { 252 final Object prototype = getPrototype(); 253 if (prototype instanceof ScriptObject) { 254 object.setInitialProto((ScriptObject)prototype); 255 } 256 257 if (object.getProto() == null) { 258 object.setInitialProto(getObjectPrototype()); 259 } 260 } 261 262 return object; 263 } 264 265 /** 266 * Return Object.prototype - used by "allocate" 267 * @return Object.prototype 268 */ 269 protected abstract ScriptObject getObjectPrototype(); 270 271 /** 272 * Creates a version of this function bound to a specific "self" and other arguments, as per 273 * {@code Function.prototype.bind} functionality in ECMAScript 5.1 section 15.3.4.5. 274 * @param self the self to bind to this function. Can be null (in which case, null is bound as this). 275 * @param args additional arguments to bind to this function. Can be null or empty to not bind additional arguments. 276 * @return a function with the specified self and parameters bound. 277 */ 278 protected ScriptFunction makeBoundFunction(final Object self, final Object[] args) { 279 return makeBoundFunction(data.makeBoundFunctionData(this, self, args)); 280 } 281 282 /** 283 * Create a version of this function as in {@link ScriptFunction#makeBoundFunction(Object, Object[])}, 284 * but using a {@link ScriptFunctionData} for the bound data. 285 * 286 * @param boundData ScriptFuntionData for the bound function 287 * @return a function with the bindings performed according to the given data 288 */ 289 protected abstract ScriptFunction makeBoundFunction(ScriptFunctionData boundData); 290 291 @Override 292 public final String safeToString() { 293 return toSource(); 294 } 295 296 @Override 297 public String toString() { 298 return data.toString(); 299 } 300 301 /** 302 * Get this function as a String containing its source code. If no source code 303 * exists in this ScriptFunction, its contents will be displayed as {@code [native code]} 304 * @return string representation of this function's source 305 */ 306 public final String toSource() { 307 return data.toSource(); 308 } 309 310 /** 311 * Get the prototype object for this function 312 * @return prototype 313 */ 314 public abstract Object getPrototype(); 315 316 /** 317 * Set the prototype object for this function 318 * @param prototype new prototype object 319 */ 320 public abstract void setPrototype(Object prototype); 321 322 /** 323 * Create a function that invokes this function synchronized on {@code sync} or the self object 324 * of the invocation. 325 * @param sync the Object to synchronize on, or undefined 326 * @return synchronized function 327 */ 328 public abstract ScriptFunction makeSynchronizedFunction(Object sync); 329 330 /** 331 * Return the invoke handle bound to a given ScriptObject self reference. 332 * If callee parameter is required result is rebound to this. 333 * 334 * @param self self reference 335 * @return bound invoke handle 336 */ 337 public final MethodHandle getBoundInvokeHandle(final Object self) { 338 return MH.bindTo(bindToCalleeIfNeeded(data.getGenericInvoker(scope)), self); 339 } 340 341 /** 342 * Bind the method handle to this {@code ScriptFunction} instance if it needs a callee parameter. If this function's 343 * method handles don't have a callee parameter, the handle is returned unchanged. 344 * @param methodHandle the method handle to potentially bind to this function instance. 345 * @return the potentially bound method handle 346 */ 347 private MethodHandle bindToCalleeIfNeeded(final MethodHandle methodHandle) { 348 return ScriptFunctionData.needsCallee(methodHandle) ? MH.bindTo(methodHandle, this) : methodHandle; 349 350 } 351 352 /** 353 * Get the name for this function 354 * @return the name 355 */ 356 public final String getName() { 357 return data.getName(); 358 } 359 360 361 /** 362 * Get the scope for this function 363 * @return the scope 364 */ 365 public final ScriptObject getScope() { 366 return scope; 367 } 368 369 /** 370 * Prototype getter for this ScriptFunction - follows the naming convention 371 * used by Nasgen and the code generator 372 * 373 * @param self self reference 374 * @return self's prototype 375 */ 376 public static Object G$prototype(final Object self) { 377 return self instanceof ScriptFunction ? 378 ((ScriptFunction)self).getPrototype() : 379 UNDEFINED; 380 } 381 382 /** 383 * Prototype setter for this ScriptFunction - follows the naming convention 384 * used by Nasgen and the code generator 385 * 386 * @param self self reference 387 * @param prototype prototype to set 388 */ 389 public static void S$prototype(final Object self, final Object prototype) { 390 if (self instanceof ScriptFunction) { 391 ((ScriptFunction)self).setPrototype(prototype); 392 } 393 } 394 395 /** 396 * Length getter - ECMA 15.3.3.2: Function.length 397 * @param self self reference 398 * @return length 399 */ 400 public static int G$length(final Object self) { 401 if (self instanceof ScriptFunction) { 402 return ((ScriptFunction)self).data.getArity(); 403 } 404 405 return 0; 406 } 407 408 /** 409 * Name getter - ECMA Function.name 410 * @param self self refence 411 * @return the name, or undefined if none 412 */ 413 public static Object G$name(final Object self) { 414 if (self instanceof ScriptFunction) { 415 return ((ScriptFunction)self).getName(); 416 } 417 418 return UNDEFINED; 419 } 420 421 /** 422 * Get the prototype for this ScriptFunction 423 * @param constructor constructor 424 * @return prototype, or null if given constructor is not a ScriptFunction 425 */ 426 public static ScriptObject getPrototype(final Object constructor) { 427 if (constructor instanceof ScriptFunction) { 428 final Object proto = ((ScriptFunction)constructor).getPrototype(); 429 if (proto instanceof ScriptObject) { 430 return (ScriptObject)proto; 431 } 432 } 433 434 return null; 435 } 436 437 // These counters are updated only in debug mode. 438 private static int constructorCount; 439 private static int invokes; 440 private static int allocations; 441 442 /** 443 * @return the constructorCount 444 */ 445 public static int getConstructorCount() { 446 return constructorCount; 447 } 448 449 /** 450 * @return the invokes 451 */ 452 public static int getInvokes() { 453 return invokes; 454 } 455 456 /** 457 * @return the allocations 458 */ 459 public static int getAllocations() { 460 return allocations; 461 } 462 463 @Override 464 protected GuardedInvocation findNewMethod(final CallSiteDescriptor desc, final LinkRequest request) { 465 final MethodType type = desc.getMethodType(); 466 assert desc.getMethodType().returnType() == Object.class && !NashornCallSiteDescriptor.isOptimistic(desc); 467 final CompiledFunction cf = data.getBestConstructor(type, scope); 468 final GuardedInvocation bestCtorInv = new GuardedInvocation(cf.getConstructor(), cf.getOptimisticAssumptionsSwitchPoint()); 469 //TODO - ClassCastException 470 return new GuardedInvocation(pairArguments(bestCtorInv.getInvocation(), type), getFunctionGuard(this, cf.getFlags()), bestCtorInv.getSwitchPoints(), null); 471 } 472 473 @SuppressWarnings("unused") 474 private static Object wrapFilter(final Object obj) { 475 if (obj instanceof ScriptObject || !ScriptFunctionData.isPrimitiveThis(obj)) { 476 return obj; 477 } 478 return Context.getGlobal().wrapAsObject(obj); 479 } 480 481 482 @SuppressWarnings("unused") 483 private static Object globalFilter(final Object object) { 484 // replace whatever we get with the current global object 485 return Context.getGlobal(); 486 } 487 488 /** 489 * dyn:call call site signature: (callee, thiz, [args...]) 490 * generated method signature: (callee, thiz, [args...]) 491 * 492 * cases: 493 * (a) method has callee parameter 494 * (1) for local/scope calls, we just bind thiz and drop the second argument. 495 * (2) for normal this-calls, we have to swap thiz and callee to get matching signatures. 496 * (b) method doesn't have callee parameter (builtin functions) 497 * (3) for local/scope calls, bind thiz and drop both callee and thiz. 498 * (4) for normal this-calls, drop callee. 499 * 500 * @return guarded invocation for call 501 */ 502 @Override 503 protected GuardedInvocation findCallMethod(final CallSiteDescriptor desc, final LinkRequest request) { 504 final MethodType type = desc.getMethodType(); 505 506 final String name = getName(); 507 final boolean isUnstable = request.isCallSiteUnstable(); 508 final boolean scopeCall = NashornCallSiteDescriptor.isScope(desc); 509 final boolean isCall = !scopeCall && data.isBuiltin() && "call".equals(name); 510 final boolean isApply = !scopeCall && data.isBuiltin() && "apply".equals(name); 511 512 final boolean isApplyOrCall = isCall | isApply; 513 514 if (isUnstable && !isApplyOrCall) { 515 //megamorphic - replace call with apply 516 final MethodHandle handle; 517 //ensure that the callsite is vararg so apply can consume it 518 if (type.parameterCount() == 3 && type.parameterType(2) == Object[].class) { 519 // Vararg call site 520 handle = ScriptRuntime.APPLY.methodHandle(); 521 } else { 522 // (callee, this, args...) => (callee, this, args[]) 523 handle = MH.asCollector(ScriptRuntime.APPLY.methodHandle(), Object[].class, type.parameterCount() - 2); 524 } 525 526 // If call site is statically typed to take a ScriptFunction, we don't need a guard, otherwise we need a 527 // generic "is this a ScriptFunction?" guard. 528 return new GuardedInvocation( 529 handle, 530 null, 531 (SwitchPoint)null, 532 ClassCastException.class); 533 } 534 535 MethodHandle boundHandle; 536 MethodHandle guard = null; 537 538 // Special handling of Function.apply and Function.call. Note we must be invoking 539 if (isApplyOrCall && !isUnstable) { 540 final Object[] args = request.getArguments(); 541 if (Bootstrap.isCallable(args[1])) { 542 return createApplyOrCallCall(isApply, desc, request, args); 543 } 544 } //else just fall through and link as ordinary function or unstable apply 545 546 final int programPoint = NashornCallSiteDescriptor.isOptimistic(desc) ? NashornCallSiteDescriptor.getProgramPoint(desc) : INVALID_PROGRAM_POINT; 547 final CompiledFunction cf = data.getBestInvoker(type, scope); 548 final GuardedInvocation bestInvoker = 549 new GuardedInvocation( 550 cf.createInvoker(type.returnType(), programPoint), 551 cf.getOptimisticAssumptionsSwitchPoint()); 552 553 final MethodHandle callHandle = bestInvoker.getInvocation(); 554 555 if (data.needsCallee()) { 556 if (scopeCall && needsWrappedThis()) { 557 // (callee, this, args...) => (callee, [this], args...) 558 boundHandle = MH.filterArguments(callHandle, 1, SCRIPTFUNCTION_GLOBALFILTER); 559 } else { 560 // It's already (callee, this, args...), just what we need 561 boundHandle = callHandle; 562 } 563 } else if (data.isBuiltin() && "extend".equals(data.getName())) { 564 // NOTE: the only built-in named "extend" is NativeJava.extend. As a special-case we're binding the 565 // current lookup as its "this" so it can do security-sensitive creation of adapter classes. 566 boundHandle = MH.dropArguments(MH.bindTo(callHandle, desc.getLookup()), 0, type.parameterType(0), type.parameterType(1)); 567 } else if (scopeCall && needsWrappedThis()) { 568 // Make a handle that drops the passed "this" argument and substitutes either Global or Undefined 569 // (this, args...) => ([this], args...) 570 boundHandle = MH.filterArguments(callHandle, 0, SCRIPTFUNCTION_GLOBALFILTER); 571 // ([this], args...) => ([callee], [this], args...) 572 boundHandle = MH.dropArguments(boundHandle, 0, type.parameterType(0)); 573 } else { 574 // (this, args...) => ([callee], this, args...) 575 boundHandle = MH.dropArguments(callHandle, 0, type.parameterType(0)); 576 } 577 578 // For non-strict functions, check whether this-object is primitive type. 579 // If so add a to-object-wrapper argument filter. 580 // Else install a guard that will trigger a relink when the argument becomes primitive. 581 if (!scopeCall && needsWrappedThis()) { 582 if (ScriptFunctionData.isPrimitiveThis(request.getArguments()[1])) { 583 boundHandle = MH.filterArguments(boundHandle, 1, WRAPFILTER); 584 } else { 585 guard = getNonStrictFunctionGuard(this); 586 } 587 } 588 589 boundHandle = pairArguments(boundHandle, type); 590 591 return new GuardedInvocation(boundHandle, guard == null ? getFunctionGuard(this, cf.getFlags()) : guard, bestInvoker.getSwitchPoints(), null); 592 } 593 594 private GuardedInvocation createApplyOrCallCall(final boolean isApply, final CallSiteDescriptor desc, final LinkRequest request, final Object[] args) { 595 final MethodType descType = desc.getMethodType(); 596 final int paramCount = descType.parameterCount(); 597 if(descType.parameterType(paramCount - 1).isArray()) { 598 // This is vararg invocation of apply or call. This can normally only happen when we do a recursive 599 // invocation of createApplyOrCallCall (because we're doing apply-of-apply). In this case, create delegate 600 // linkage by unpacking the vararg invocation and use pairArguments to introduce the necessary spreader. 601 return createVarArgApplyOrCallCall(isApply, desc, request, args); 602 } 603 604 final boolean passesThis = paramCount > 2; 605 final boolean passesArgs = paramCount > 3; 606 final int realArgCount = passesArgs ? paramCount - 3 : 0; 607 608 final Object appliedFn = args[1]; 609 final boolean appliedFnNeedsWrappedThis = needsWrappedThis(appliedFn); 610 611 //box call back to apply 612 CallSiteDescriptor appliedDesc = desc; 613 final SwitchPoint applyToCallSwitchPoint = Global.instance().getChangeCallback("apply"); 614 //enough to change the proto switchPoint here 615 616 final boolean isApplyToCall = NashornCallSiteDescriptor.isApplyToCall(desc); 617 final boolean isFailedApplyToCall = isApplyToCall && applyToCallSwitchPoint.hasBeenInvalidated(); 618 619 // R(apply|call, ...) => R(...) 620 MethodType appliedType = descType.dropParameterTypes(0, 1); 621 if (!passesThis) { 622 // R() => R(this) 623 appliedType = appliedType.insertParameterTypes(1, Object.class); 624 } else if (appliedFnNeedsWrappedThis) { 625 appliedType = appliedType.changeParameterType(1, Object.class); 626 } 627 628 if (isApply || isFailedApplyToCall) { 629 if (passesArgs) { 630 // R(this, args) => R(this, Object[]) 631 appliedType = appliedType.changeParameterType(2, Object[].class); 632 // drop any extraneous arguments for the apply fail case 633 if (isFailedApplyToCall) { 634 appliedType = appliedType.dropParameterTypes(3, paramCount - 1); 635 } 636 } else { 637 // R(this) => R(this, Object[]) 638 appliedType = appliedType.insertParameterTypes(2, Object[].class); 639 } 640 } 641 642 appliedDesc = appliedDesc.changeMethodType(appliedType); 643 644 // Create the same arguments for the delegate linking request that would be passed in an actual apply'd invocation 645 final Object[] appliedArgs = new Object[isApply ? 3 : appliedType.parameterCount()]; 646 appliedArgs[0] = appliedFn; 647 appliedArgs[1] = passesThis ? appliedFnNeedsWrappedThis ? ScriptFunctionData.wrapThis(args[2]) : args[2] : ScriptRuntime.UNDEFINED; 648 if (isApply && !isFailedApplyToCall) { 649 appliedArgs[2] = passesArgs ? NativeFunction.toApplyArgs(args[3]) : ScriptRuntime.EMPTY_ARRAY; 650 } else { 651 if (passesArgs) { 652 if (isFailedApplyToCall) { 653 final Object[] tmp = new Object[args.length - 3]; 654 System.arraycopy(args, 3, tmp, 0, tmp.length); 655 appliedArgs[2] = NativeFunction.toApplyArgs(tmp); 656 } else { 657 assert !isApply; 658 System.arraycopy(args, 3, appliedArgs, 2, args.length - 3); 659 } 660 } else if (isFailedApplyToCall) { 661 appliedArgs[2] = ScriptRuntime.EMPTY_ARRAY; 662 } 663 } 664 665 // Ask the linker machinery for an invocation of the target function 666 final LinkRequest appliedRequest = request.replaceArguments(appliedDesc, appliedArgs); 667 GuardedInvocation appliedInvocation; 668 try { 669 appliedInvocation = Bootstrap.getLinkerServices().getGuardedInvocation(appliedRequest); 670 } catch (final RuntimeException | Error e) { 671 throw e; 672 } catch (final Exception e) { 673 throw new RuntimeException(e); 674 } 675 assert appliedRequest != null; // Bootstrap.isCallable() returned true for args[1], so it must produce a linkage. 676 677 final Class<?> applyFnType = descType.parameterType(0); 678 MethodHandle inv = appliedInvocation.getInvocation(); //method handle from apply invocation. the applied function invocation 679 680 if (isApply && !isFailedApplyToCall) { 681 if (passesArgs) { 682 // Make sure that the passed argArray is converted to Object[] the same way NativeFunction.apply() would do it. 683 inv = MH.filterArguments(inv, 2, NativeFunction.TO_APPLY_ARGS); 684 } else { 685 // If the original call site doesn't pass argArray, pass in an empty array 686 inv = MH.insertArguments(inv, 2, (Object)ScriptRuntime.EMPTY_ARRAY); 687 } 688 } 689 690 if (isApplyToCall) { 691 if (isFailedApplyToCall) { 692 //take the real arguments that were passed to a call and force them into the apply instead 693 Context.getContextTrusted().getLogger(ApplySpecialization.class).info("Collection arguments to revert call to apply in " + appliedFn); 694 inv = MH.asCollector(inv, Object[].class, realArgCount); 695 } else { 696 appliedInvocation = appliedInvocation.addSwitchPoint(applyToCallSwitchPoint); 697 } 698 } 699 700 if (!passesThis) { 701 // If the original call site doesn't pass in a thisArg, pass in Global/undefined as needed 702 inv = bindImplicitThis(appliedFn, inv); 703 } else if (appliedFnNeedsWrappedThis) { 704 // target function needs a wrapped this, so make sure we filter for that 705 inv = MH.filterArguments(inv, 1, WRAP_THIS); 706 } 707 inv = MH.dropArguments(inv, 0, applyFnType); 708 709 MethodHandle guard = appliedInvocation.getGuard(); 710 // If the guard checks the value of "this" but we aren't passing thisArg, insert the default one 711 if (!passesThis && guard.type().parameterCount() > 1) { 712 guard = bindImplicitThis(appliedFn, guard); 713 } 714 final MethodType guardType = guard.type(); 715 716 // We need to account for the dropped (apply|call) function argument. 717 guard = MH.dropArguments(guard, 0, descType.parameterType(0)); 718 // Take the "isApplyFunction" guard, and bind it to this function. 719 MethodHandle applyFnGuard = MH.insertArguments(IS_APPLY_FUNCTION, 2, this); 720 // Adapt the guard to receive all the arguments that the original guard does. 721 applyFnGuard = MH.dropArguments(applyFnGuard, 2, guardType.parameterArray()); 722 // Fold the original function guard into our apply guard. 723 guard = MH.foldArguments(applyFnGuard, guard); 724 725 return appliedInvocation.replaceMethods(inv, guard); 726 } 727 728 /* 729 * This method is used for linking nested apply. Specialized apply and call linking will create a variable arity 730 * call site for an apply call; when createApplyOrCallCall sees a linking request for apply or call with 731 * Nashorn-style variable arity call site (last argument type is Object[]) it'll delegate to this method. 732 * This method converts the link request from a vararg to a non-vararg one (unpacks the array), then delegates back 733 * to createApplyOrCallCall (with which it is thus mutually recursive), and adds appropriate argument spreaders to 734 * invocation and the guard of whatever createApplyOrCallCall returned to adapt it back into a variable arity 735 * invocation. It basically reduces the problem of vararg call site linking of apply and call back to the (already 736 * solved by createApplyOrCallCall) non-vararg call site linking. 737 */ 738 private GuardedInvocation createVarArgApplyOrCallCall(final boolean isApply, final CallSiteDescriptor desc, 739 final LinkRequest request, final Object[] args) { 740 final MethodType descType = desc.getMethodType(); 741 final int paramCount = descType.parameterCount(); 742 final Object[] varArgs = (Object[])args[paramCount - 1]; 743 // -1 'cause we're not passing the vararg array itself 744 final int copiedArgCount = args.length - 1; 745 int varArgCount = varArgs.length; 746 747 // Spread arguments for the delegate createApplyOrCallCall invocation. 748 final Object[] spreadArgs = new Object[copiedArgCount + varArgCount]; 749 System.arraycopy(args, 0, spreadArgs, 0, copiedArgCount); 750 System.arraycopy(varArgs, 0, spreadArgs, copiedArgCount, varArgCount); 751 752 // Spread call site descriptor for the delegate createApplyOrCallCall invocation. We drop vararg array and 753 // replace it with a list of Object.class. 754 final MethodType spreadType = descType.dropParameterTypes(paramCount - 1, paramCount).appendParameterTypes( 755 Collections.<Class<?>>nCopies(varArgCount, Object.class)); 756 final CallSiteDescriptor spreadDesc = desc.changeMethodType(spreadType); 757 758 // Delegate back to createApplyOrCallCall with the spread (that is, reverted to non-vararg) request/ 759 final LinkRequest spreadRequest = request.replaceArguments(spreadDesc, spreadArgs); 760 final GuardedInvocation spreadInvocation = createApplyOrCallCall(isApply, spreadDesc, spreadRequest, spreadArgs); 761 762 // Add spreader combinators to returned invocation and guard. 763 return spreadInvocation.replaceMethods( 764 // Use standard ScriptObject.pairArguments on the invocation 765 pairArguments(spreadInvocation.getInvocation(), descType), 766 // Use our specialized spreadGuardArguments on the guard (see below). 767 spreadGuardArguments(spreadInvocation.getGuard(), descType)); 768 } 769 770 private static MethodHandle spreadGuardArguments(final MethodHandle guard, final MethodType descType) { 771 final MethodType guardType = guard.type(); 772 final int guardParamCount = guardType.parameterCount(); 773 final int descParamCount = descType.parameterCount(); 774 final int spreadCount = guardParamCount - descParamCount + 1; 775 if (spreadCount <= 0) { 776 // Guard doesn't dip into the varargs 777 return guard; 778 } 779 780 final MethodHandle arrayConvertingGuard; 781 // If the last parameter type of the guard is an array, then it is already itself a guard for a vararg apply 782 // invocation. We must filter the last argument with toApplyArgs otherwise deeper levels of nesting will fail 783 // with ClassCastException of NativeArray to Object[]. 784 if(guardType.parameterType(guardParamCount - 1).isArray()) { 785 arrayConvertingGuard = MH.filterArguments(guard, guardParamCount - 1, NativeFunction.TO_APPLY_ARGS); 786 } else { 787 arrayConvertingGuard = guard; 788 } 789 790 return ScriptObject.adaptHandleToVarArgCallSite(arrayConvertingGuard, descParamCount); 791 } 792 793 private static MethodHandle bindImplicitThis(final Object fn, final MethodHandle mh) { 794 final MethodHandle bound; 795 if(fn instanceof ScriptFunction && ((ScriptFunction)fn).needsWrappedThis()) { 796 bound = MH.filterArguments(mh, 1, SCRIPTFUNCTION_GLOBALFILTER); 797 } else { 798 bound = mh; 799 } 800 return MH.insertArguments(bound, 1, ScriptRuntime.UNDEFINED); 801 } 802 803 /** 804 * Used for noSuchMethod/noSuchProperty and JSAdapter hooks. 805 * 806 * These don't want a callee parameter, so bind that. Name binding is optional. 807 */ 808 MethodHandle getCallMethodHandle(final MethodType type, final String bindName) { 809 return pairArguments(bindToNameIfNeeded(bindToCalleeIfNeeded(data.getGenericInvoker(scope)), bindName), type); 810 } 811 812 private static MethodHandle bindToNameIfNeeded(final MethodHandle methodHandle, final String bindName) { 813 if (bindName == null) { 814 return methodHandle; 815 } 816 817 // if it is vararg method, we need to extend argument array with 818 // a new zeroth element that is set to bindName value. 819 final MethodType methodType = methodHandle.type(); 820 final int parameterCount = methodType.parameterCount(); 821 final boolean isVarArg = parameterCount > 0 && methodType.parameterType(parameterCount - 1).isArray(); 822 823 if (isVarArg) { 824 return MH.filterArguments(methodHandle, 1, MH.insertArguments(ADD_ZEROTH_ELEMENT, 1, bindName)); 825 } 826 return MH.insertArguments(methodHandle, 1, bindName); 827 } 828 829 /** 830 * Get the guard that checks if a {@link ScriptFunction} is equal to 831 * a known ScriptFunction, using reference comparison 832 * 833 * @param function The ScriptFunction to check against. This will be bound to the guard method handle 834 * 835 * @return method handle for guard 836 */ 837 private static MethodHandle getFunctionGuard(final ScriptFunction function, final int flags) { 838 assert function.data != null; 839 // Built-in functions have a 1-1 correspondence to their ScriptFunctionData, so we can use a cheaper identity 840 // comparison for them. 841 if (function.data.isBuiltin()) { 842 return Guards.getIdentityGuard(function); 843 } 844 return MH.insertArguments(IS_FUNCTION_MH, 1, function.data); 845 } 846 847 /** 848 * Get a guard that checks if a {@link ScriptFunction} is equal to 849 * a known ScriptFunction using reference comparison, and whether the type of 850 * the second argument (this-object) is not a JavaScript primitive type. 851 * 852 * @param function The ScriptFunction to check against. This will be bound to the guard method handle 853 * 854 * @return method handle for guard 855 */ 856 private static MethodHandle getNonStrictFunctionGuard(final ScriptFunction function) { 857 assert function.data != null; 858 return MH.insertArguments(IS_NONSTRICT_FUNCTION, 2, function.data); 859 } 860 861 @SuppressWarnings("unused") 862 private static boolean isFunctionMH(final Object self, final ScriptFunctionData data) { 863 return self instanceof ScriptFunction && ((ScriptFunction)self).data == data; 864 } 865 866 @SuppressWarnings("unused") 867 private static boolean isNonStrictFunction(final Object self, final Object arg, final ScriptFunctionData data) { 868 return self instanceof ScriptFunction && ((ScriptFunction)self).data == data && arg instanceof ScriptObject; 869 } 870 871 @SuppressWarnings("unused") 872 private static boolean isApplyFunction(final boolean appliedFnCondition, final Object self, final Object expectedSelf) { 873 // NOTE: we're using self == expectedSelf as we're only using this with built-in functions apply() and call() 874 return appliedFnCondition && self == expectedSelf; 875 } 876 877 @SuppressWarnings("unused") 878 private static Object[] addZerothElement(final Object[] args, final Object value) { 879 // extends input array with by adding new zeroth element 880 final Object[] src = args == null? ScriptRuntime.EMPTY_ARRAY : args; 881 final Object[] result = new Object[src.length + 1]; 882 System.arraycopy(src, 0, result, 1, src.length); 883 result[0] = value; 884 return result; 885 } 886 887 @SuppressWarnings("unused") 888 private static Object invokeSync(final ScriptFunction func, final Object sync, final Object self, final Object... args) 889 throws Throwable { 890 final Object syncObj = sync == UNDEFINED ? self : sync; 891 synchronized (syncObj) { 892 return func.invoke(self, args); 893 } 894 } 895 896 private static MethodHandle findOwnMH_S(final String name, final Class<?> rtype, final Class<?>... types) { 897 return MH.findStatic(MethodHandles.lookup(), ScriptFunction.class, name, MH.type(rtype, types)); 898 } 899 900 private static MethodHandle findOwnMH_V(final String name, final Class<?> rtype, final Class<?>... types) { 901 return MH.findVirtual(MethodHandles.lookup(), ScriptFunction.class, name, MH.type(rtype, types)); 902 } 903} 904 905