1 /* 2 * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package com.sun.tools.javac.jvm; 27 28 import java.util.HashMap; 29 import java.util.Map; 30 import java.util.Set; 31 32 import com.sun.tools.javac.jvm.PoolConstant.LoadableConstant; 33 import com.sun.tools.javac.tree.TreeInfo.PosKind; 34 import com.sun.tools.javac.util.*; 35 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; 36 import com.sun.tools.javac.util.List; 37 import com.sun.tools.javac.code.*; 38 import com.sun.tools.javac.code.Attribute.TypeCompound; 39 import com.sun.tools.javac.code.Symbol.VarSymbol; 40 import com.sun.tools.javac.comp.*; 41 import com.sun.tools.javac.tree.*; 42 43 import com.sun.tools.javac.code.Symbol.*; 44 import com.sun.tools.javac.code.Type.*; 45 import com.sun.tools.javac.jvm.Code.*; 46 import com.sun.tools.javac.jvm.Items.*; 47 import com.sun.tools.javac.resources.CompilerProperties.Errors; 48 import com.sun.tools.javac.tree.EndPosTable; 49 import com.sun.tools.javac.tree.JCTree.*; 50 51 import static com.sun.tools.javac.code.Flags.*; 52 import static com.sun.tools.javac.code.Kinds.Kind.*; 53 import static com.sun.tools.javac.code.TypeTag.*; 54 import static com.sun.tools.javac.jvm.ByteCodes.*; 55 import static com.sun.tools.javac.jvm.CRTFlags.*; 56 import static com.sun.tools.javac.main.Option.*; 57 import static com.sun.tools.javac.tree.JCTree.Tag.*; 58 59 /** This pass maps flat Java (i.e. without inner classes) to bytecodes. 60 * 61 * <p><b>This is NOT part of any supported API. 62 * If you write code that depends on this, you do so at your own risk. 63 * This code and its internal interfaces are subject to change or 64 * deletion without notice.</b> 65 */ 66 public class Gen extends JCTree.Visitor { 67 protected static final Context.Key<Gen> genKey = new Context.Key<>(); 68 69 private final Log log; 70 private final Symtab syms; 71 private final Check chk; 72 private final Resolve rs; 73 private final TreeMaker make; 74 private final Names names; 75 private final Target target; 76 private final String accessDollar; 77 private final Types types; 78 private final Lower lower; 79 private final Annotate annotate; 80 private final StringConcat concat; 81 82 /** Format of stackmap tables to be generated. */ 83 private final Code.StackMapFormat stackMap; 84 85 /** A type that serves as the expected type for all method expressions. 86 */ 87 private final Type methodType; 88 89 public static Gen instance(Context context) { 90 Gen instance = context.get(genKey); 91 if (instance == null) 92 instance = new Gen(context); 93 return instance; 94 } 95 96 /** Constant pool writer, set by genClass. 97 */ 98 final PoolWriter poolWriter; 99 100 private final UnsetFieldsInfo unsetFieldsInfo; 101 102 @SuppressWarnings("this-escape") 103 protected Gen(Context context) { 104 context.put(genKey, this); 105 106 names = Names.instance(context); 107 log = Log.instance(context); 108 syms = Symtab.instance(context); 109 chk = Check.instance(context); 110 rs = Resolve.instance(context); 111 make = TreeMaker.instance(context); 112 target = Target.instance(context); 113 types = Types.instance(context); 114 concat = StringConcat.instance(context); 115 116 methodType = new MethodType(null, null, null, syms.methodClass); 117 accessDollar = "access" + target.syntheticNameChar(); 118 lower = Lower.instance(context); 119 120 Options options = Options.instance(context); 121 lineDebugInfo = 122 options.isUnset(G_CUSTOM) || 123 options.isSet(G_CUSTOM, "lines"); 124 varDebugInfo = 125 options.isUnset(G_CUSTOM) 126 ? options.isSet(G) 127 : options.isSet(G_CUSTOM, "vars"); 128 genCrt = options.isSet(XJCOV); 129 debugCode = options.isSet("debug.code"); 130 disableVirtualizedPrivateInvoke = options.isSet("disableVirtualizedPrivateInvoke"); 131 poolWriter = new PoolWriter(types, names); 132 unsetFieldsInfo = UnsetFieldsInfo.instance(context); 133 134 // ignore cldc because we cannot have both stackmap formats 135 this.stackMap = StackMapFormat.JSR202; 136 annotate = Annotate.instance(context); 137 qualifiedSymbolCache = new HashMap<>(); 138 generateEarlyLarvalFrame = options.isSet("generateEarlyLarvalFrame"); 139 Preview preview = Preview.instance(context); 140 Source source = Source.instance(context); 141 allowValueClasses = (!preview.isPreview(Source.Feature.VALUE_CLASSES) || preview.isEnabled()) && 142 Source.Feature.VALUE_CLASSES.allowedInSource(source); 143 } 144 145 /** Switches 146 */ 147 private final boolean lineDebugInfo; 148 private final boolean varDebugInfo; 149 private final boolean genCrt; 150 private final boolean debugCode; 151 private boolean disableVirtualizedPrivateInvoke; 152 private boolean generateEarlyLarvalFrame; 153 private final boolean allowValueClasses; 154 155 /** Code buffer, set by genMethod. 156 */ 157 private Code code; 158 159 /** Items structure, set by genMethod. 160 */ 161 private Items items; 162 163 /** Environment for symbol lookup, set by genClass 164 */ 165 private Env<AttrContext> attrEnv; 166 167 /** The top level tree. 168 */ 169 private JCCompilationUnit toplevel; 170 171 /** The number of code-gen errors in this class. 172 */ 173 private int nerrs = 0; 174 175 /** An object containing mappings of syntax trees to their 176 * ending source positions. 177 */ 178 EndPosTable endPosTable; 179 180 boolean inCondSwitchExpression; 181 Chain switchExpressionTrueChain; 182 Chain switchExpressionFalseChain; 183 List<LocalItem> stackBeforeSwitchExpression; 184 LocalItem switchResult; 185 PatternMatchingCatchConfiguration patternMatchingCatchConfiguration = 186 new PatternMatchingCatchConfiguration(Set.of(), null, null, null); 187 188 /** Cache the symbol to reflect the qualifying type. 189 * key: corresponding type 190 * value: qualified symbol 191 */ 192 Map<Type, Symbol> qualifiedSymbolCache; 193 194 /** Generate code to load an integer constant. 195 * @param n The integer to be loaded. 196 */ 197 void loadIntConst(int n) { 198 items.makeImmediateItem(syms.intType, n).load(); 199 } 200 201 /** The opcode that loads a zero constant of a given type code. 202 * @param tc The given type code (@see ByteCode). 203 */ 204 public static int zero(int tc) { 205 switch(tc) { 206 case INTcode: case BYTEcode: case SHORTcode: case CHARcode: 207 return iconst_0; 208 case LONGcode: 209 return lconst_0; 210 case FLOATcode: 211 return fconst_0; 212 case DOUBLEcode: 213 return dconst_0; 214 default: 215 throw new AssertionError("zero"); 216 } 217 } 218 219 /** The opcode that loads a one constant of a given type code. 220 * @param tc The given type code (@see ByteCode). 221 */ 222 public static int one(int tc) { 223 return zero(tc) + 1; 224 } 225 226 /** Generate code to load -1 of the given type code (either int or long). 227 * @param tc The given type code (@see ByteCode). 228 */ 229 void emitMinusOne(int tc) { 230 if (tc == LONGcode) { 231 items.makeImmediateItem(syms.longType, Long.valueOf(-1)).load(); 232 } else { 233 code.emitop0(iconst_m1); 234 } 235 } 236 237 /** Construct a symbol to reflect the qualifying type that should 238 * appear in the byte code as per JLS 13.1. 239 * 240 * For {@literal target >= 1.2}: Clone a method with the qualifier as owner (except 241 * for those cases where we need to work around VM bugs). 242 * 243 * For {@literal target <= 1.1}: If qualified variable or method is defined in a 244 * non-accessible class, clone it with the qualifier class as owner. 245 * 246 * @param sym The accessed symbol 247 * @param site The qualifier's type. 248 */ 249 Symbol binaryQualifier(Symbol sym, Type site) { 250 251 if (site.hasTag(ARRAY)) { 252 if (sym == syms.lengthVar || 253 sym.owner != syms.arrayClass) 254 return sym; 255 // array clone can be qualified by the array type in later targets 256 Symbol qualifier; 257 if ((qualifier = qualifiedSymbolCache.get(site)) == null) { 258 qualifier = new ClassSymbol(Flags.PUBLIC, site.tsym.name, site, syms.noSymbol); 259 qualifiedSymbolCache.put(site, qualifier); 260 } 261 return sym.clone(qualifier); 262 } 263 264 if (sym.owner == site.tsym || 265 (sym.flags() & (STATIC | SYNTHETIC)) == (STATIC | SYNTHETIC)) { 266 return sym; 267 } 268 269 // leave alone methods inherited from Object 270 // JLS 13.1. 271 if (sym.owner == syms.objectType.tsym) 272 return sym; 273 274 return sym.clone(site.tsym); 275 } 276 277 /** Insert a reference to given type in the constant pool, 278 * checking for an array with too many dimensions; 279 * return the reference's index. 280 * @param type The type for which a reference is inserted. 281 */ 282 int makeRef(DiagnosticPosition pos, Type type) { 283 return poolWriter.putClass(checkDimension(pos, type)); 284 } 285 286 /** Check if the given type is an array with too many dimensions. 287 */ 288 private Type checkDimension(DiagnosticPosition pos, Type t) { 289 checkDimensionInternal(pos, t); 290 return t; 291 } 292 293 private void checkDimensionInternal(DiagnosticPosition pos, Type t) { 294 switch (t.getTag()) { 295 case METHOD: 296 checkDimension(pos, t.getReturnType()); 297 for (List<Type> args = t.getParameterTypes(); args.nonEmpty(); args = args.tail) 298 checkDimension(pos, args.head); 299 break; 300 case ARRAY: 301 if (types.dimensions(t) > ClassFile.MAX_DIMENSIONS) { 302 log.error(pos, Errors.LimitDimensions); 303 nerrs++; 304 } 305 break; 306 default: 307 break; 308 } 309 } 310 311 /** Create a temporary variable. 312 * @param type The variable's type. 313 */ 314 LocalItem makeTemp(Type type) { 315 VarSymbol v = new VarSymbol(Flags.SYNTHETIC, 316 names.empty, 317 type, 318 env.enclMethod.sym); 319 code.newLocal(v); 320 return items.makeLocalItem(v); 321 } 322 323 /** Generate code to call a non-private method or constructor. 324 * @param pos Position to be used for error reporting. 325 * @param site The type of which the method is a member. 326 * @param name The method's name. 327 * @param argtypes The method's argument types. 328 * @param isStatic A flag that indicates whether we call a 329 * static or instance method. 330 */ 331 void callMethod(DiagnosticPosition pos, 332 Type site, Name name, List<Type> argtypes, 333 boolean isStatic) { 334 Symbol msym = rs. 335 resolveInternalMethod(pos, attrEnv, site, name, argtypes, null); 336 if (isStatic) items.makeStaticItem(msym).invoke(); 337 else items.makeMemberItem(msym, name == names.init).invoke(); 338 } 339 340 /** Is the given method definition an access method 341 * resulting from a qualified super? This is signified by an odd 342 * access code. 343 */ 344 private boolean isAccessSuper(JCMethodDecl enclMethod) { 345 return 346 (enclMethod.mods.flags & SYNTHETIC) != 0 && 347 isOddAccessName(enclMethod.name); 348 } 349 350 /** Does given name start with "access$" and end in an odd digit? 351 */ 352 private boolean isOddAccessName(Name name) { 353 final String string = name.toString(); 354 return 355 string.startsWith(accessDollar) && 356 (string.charAt(string.length() - 1) & 1) != 0; 357 } 358 359 /* ************************************************************************ 360 * Non-local exits 361 *************************************************************************/ 362 363 /** Generate code to invoke the finalizer associated with given 364 * environment. 365 * Any calls to finalizers are appended to the environments `cont' chain. 366 * Mark beginning of gap in catch all range for finalizer. 367 */ 368 void genFinalizer(Env<GenContext> env) { 369 if (code.isAlive() && env.info.finalize != null) 370 env.info.finalize.gen(); 371 } 372 373 /** Generate code to call all finalizers of structures aborted by 374 * a non-local 375 * exit. Return target environment of the non-local exit. 376 * @param target The tree representing the structure that's aborted 377 * @param env The environment current at the non-local exit. 378 */ 379 Env<GenContext> unwind(JCTree target, Env<GenContext> env) { 380 Env<GenContext> env1 = env; 381 while (true) { 382 genFinalizer(env1); 383 if (env1.tree == target) break; 384 env1 = env1.next; 385 } 386 return env1; 387 } 388 389 /** Mark end of gap in catch-all range for finalizer. 390 * @param env the environment which might contain the finalizer 391 * (if it does, env.info.gaps != null). 392 */ 393 void endFinalizerGap(Env<GenContext> env) { 394 if (env.info.gaps != null && env.info.gaps.length() % 2 == 1) 395 env.info.gaps.append(code.curCP()); 396 } 397 398 /** Mark end of all gaps in catch-all ranges for finalizers of environments 399 * lying between, and including to two environments. 400 * @param from the most deeply nested environment to mark 401 * @param to the least deeply nested environment to mark 402 */ 403 void endFinalizerGaps(Env<GenContext> from, Env<GenContext> to) { 404 Env<GenContext> last = null; 405 while (last != to) { 406 endFinalizerGap(from); 407 last = from; 408 from = from.next; 409 } 410 } 411 412 /** Do any of the structures aborted by a non-local exit have 413 * finalizers that require an empty stack? 414 * @param target The tree representing the structure that's aborted 415 * @param env The environment current at the non-local exit. 416 */ 417 boolean hasFinally(JCTree target, Env<GenContext> env) { 418 while (env.tree != target) { 419 if (env.tree.hasTag(TRY) && env.info.finalize.hasFinalizer()) 420 return true; 421 env = env.next; 422 } 423 return false; 424 } 425 426 /* ************************************************************************ 427 * Normalizing class-members. 428 *************************************************************************/ 429 430 /** Distribute member initializer code into constructors and {@code <clinit>} 431 * method. 432 * @param defs The list of class member declarations. 433 * @param c The enclosing class. 434 */ 435 List<JCTree> normalizeDefs(List<JCTree> defs, ClassSymbol c) { 436 ListBuffer<JCStatement> initCode = new ListBuffer<>(); 437 // only used for value classes 438 ListBuffer<JCStatement> initBlocks = new ListBuffer<>(); 439 ListBuffer<Attribute.TypeCompound> initTAs = new ListBuffer<>(); 440 ListBuffer<JCStatement> clinitCode = new ListBuffer<>(); 441 ListBuffer<Attribute.TypeCompound> clinitTAs = new ListBuffer<>(); 442 ListBuffer<JCTree> methodDefs = new ListBuffer<>(); 443 // Sort definitions into three listbuffers: 444 // - initCode for instance initializers 445 // - clinitCode for class initializers 446 // - methodDefs for method definitions 447 for (List<JCTree> l = defs; l.nonEmpty(); l = l.tail) { 448 JCTree def = l.head; 449 switch (def.getTag()) { 450 case BLOCK: 451 JCBlock block = (JCBlock)def; 452 if ((block.flags & STATIC) != 0) 453 clinitCode.append(block); 454 else if ((block.flags & SYNTHETIC) == 0) { 455 if (c.isValueClass() || c.hasStrict()) { 456 initBlocks.append(block); 457 } else { 458 initCode.append(block); 459 } 460 } 461 break; 462 case METHODDEF: 463 methodDefs.append(def); 464 break; 465 case VARDEF: 466 JCVariableDecl vdef = (JCVariableDecl) def; 467 VarSymbol sym = vdef.sym; 468 checkDimension(vdef.pos(), sym.type); 469 if (vdef.init != null) { 470 if ((sym.flags() & STATIC) == 0) { 471 // Always initialize instance variables. 472 JCStatement init = make.at(vdef.pos()). 473 Assignment(sym, vdef.init); 474 initCode.append(init); 475 endPosTable.replaceTree(vdef, init); 476 initTAs.addAll(getAndRemoveNonFieldTAs(sym)); 477 } else if (sym.getConstValue() == null) { 478 // Initialize class (static) variables only if 479 // they are not compile-time constants. 480 JCStatement init = make.at(vdef.pos). 481 Assignment(sym, vdef.init); 482 clinitCode.append(init); 483 endPosTable.replaceTree(vdef, init); 484 clinitTAs.addAll(getAndRemoveNonFieldTAs(sym)); 485 } else { 486 checkStringConstant(vdef.init.pos(), sym.getConstValue()); 487 /* if the init contains a reference to an external class, add it to the 488 * constant's pool 489 */ 490 vdef.init.accept(classReferenceVisitor); 491 } 492 } 493 break; 494 default: 495 Assert.error(); 496 } 497 } 498 // Insert any instance initializers into all constructors. 499 if (initCode.length() != 0 || initBlocks.length() != 0) { 500 initTAs.addAll(c.getInitTypeAttributes()); 501 List<Attribute.TypeCompound> initTAlist = initTAs.toList(); 502 for (JCTree t : methodDefs) { 503 normalizeMethod((JCMethodDecl)t, initCode.toList(), initBlocks.toList(), initTAlist); 504 } 505 } 506 // If there are class initializers, create a <clinit> method 507 // that contains them as its body. 508 if (clinitCode.length() != 0) { 509 MethodSymbol clinit = new MethodSymbol( 510 STATIC | (c.flags() & STRICTFP), 511 names.clinit, 512 new MethodType( 513 List.nil(), syms.voidType, 514 List.nil(), syms.methodClass), 515 c); 516 c.members().enter(clinit); 517 List<JCStatement> clinitStats = clinitCode.toList(); 518 JCBlock block = make.at(clinitStats.head.pos()).Block(0, clinitStats); 519 block.endpos = TreeInfo.endPos(clinitStats.last()); 520 methodDefs.append(make.MethodDef(clinit, block)); 521 522 if (!clinitTAs.isEmpty()) 523 clinit.appendUniqueTypeAttributes(clinitTAs.toList()); 524 if (!c.getClassInitTypeAttributes().isEmpty()) 525 clinit.appendUniqueTypeAttributes(c.getClassInitTypeAttributes()); 526 } 527 // Return all method definitions. 528 return methodDefs.toList(); 529 } 530 531 private List<Attribute.TypeCompound> getAndRemoveNonFieldTAs(VarSymbol sym) { 532 List<TypeCompound> tas = sym.getRawTypeAttributes(); 533 ListBuffer<Attribute.TypeCompound> fieldTAs = new ListBuffer<>(); 534 ListBuffer<Attribute.TypeCompound> nonfieldTAs = new ListBuffer<>(); 535 for (TypeCompound ta : tas) { 536 Assert.check(ta.getPosition().type != TargetType.UNKNOWN); 537 if (ta.getPosition().type == TargetType.FIELD) { 538 fieldTAs.add(ta); 539 } else { 540 nonfieldTAs.add(ta); 541 } 542 } 543 sym.setTypeAttributes(fieldTAs.toList()); 544 return nonfieldTAs.toList(); 545 } 546 547 /** Check a constant value and report if it is a string that is 548 * too large. 549 */ 550 private void checkStringConstant(DiagnosticPosition pos, Object constValue) { 551 if (nerrs != 0 || // only complain about a long string once 552 constValue == null || 553 !(constValue instanceof String str) || 554 str.length() < PoolWriter.MAX_STRING_LENGTH) 555 return; 556 log.error(pos, Errors.LimitString); 557 nerrs++; 558 } 559 560 /** Insert instance initializer code into constructors prior to the super() call. 561 * @param md The tree potentially representing a 562 * constructor's definition. 563 * @param initCode The list of instance initializer statements. 564 * @param initTAs Type annotations from the initializer expression. 565 */ 566 void normalizeMethod(JCMethodDecl md, List<JCStatement> initCode, List<JCStatement> initBlocks, List<TypeCompound> initTAs) { 567 if (TreeInfo.isConstructor(md) && TreeInfo.hasConstructorCall(md, names._super)) { 568 // We are seeing a constructor that has a super() call. 569 // Find the super() invocation and append the given initializer code. 570 if (allowValueClasses & (md.sym.owner.isValueClass() || md.sym.owner.hasStrict() || ((md.sym.owner.flags_field & RECORD) != 0))) { 571 rewriteInitializersIfNeeded(md, initCode); 572 md.body.stats = initCode.appendList(md.body.stats); 573 TreeInfo.mapSuperCalls(md.body, supercall -> make.Block(0, initBlocks.prepend(supercall))); 574 } else { 575 TreeInfo.mapSuperCalls(md.body, supercall -> make.Block(0, initCode.prepend(supercall))); 576 } 577 578 if (md.body.endpos == Position.NOPOS) 579 md.body.endpos = TreeInfo.endPos(md.body.stats.last()); 580 581 md.sym.appendUniqueTypeAttributes(initTAs); 582 } 583 } 584 585 void rewriteInitializersIfNeeded(JCMethodDecl md, List<JCStatement> initCode) { 586 if (lower.initializerOuterThis.containsKey(md.sym.owner)) { 587 InitializerVisitor initializerVisitor = new InitializerVisitor(md, lower.initializerOuterThis.get(md.sym.owner)); 588 for (JCStatement init : initCode) { 589 initializerVisitor.scan(init); 590 } 591 } 592 } 593 594 public static class InitializerVisitor extends TreeScanner { 595 JCMethodDecl md; 596 Set<JCExpression> exprSet; 597 598 public InitializerVisitor(JCMethodDecl md, Set<JCExpression> exprSet) { 599 this.md = md; 600 this.exprSet = exprSet; 601 } 602 603 @Override 604 public void visitTree(JCTree tree) {} 605 606 @Override 607 public void visitIdent(JCIdent tree) { 608 if (exprSet.contains(tree)) { 609 for (JCVariableDecl param: md.params) { 610 if (param.name == tree.name && 611 ((param.sym.flags_field & (MANDATED | NOOUTERTHIS)) == (MANDATED | NOOUTERTHIS))) { 612 tree.sym = param.sym; 613 } 614 } 615 } 616 } 617 } 618 619 /* ************************************************************************ 620 * Traversal methods 621 *************************************************************************/ 622 623 /** Visitor argument: The current environment. 624 */ 625 Env<GenContext> env; 626 627 /** Visitor argument: The expected type (prototype). 628 */ 629 Type pt; 630 631 /** Visitor result: The item representing the computed value. 632 */ 633 Item result; 634 635 /** Visitor method: generate code for a definition, catching and reporting 636 * any completion failures. 637 * @param tree The definition to be visited. 638 * @param env The environment current at the definition. 639 */ 640 public void genDef(JCTree tree, Env<GenContext> env) { 641 Env<GenContext> prevEnv = this.env; 642 try { 643 this.env = env; 644 tree.accept(this); 645 } catch (CompletionFailure ex) { 646 chk.completionError(tree.pos(), ex); 647 } finally { 648 this.env = prevEnv; 649 } 650 } 651 652 /** Derived visitor method: check whether CharacterRangeTable 653 * should be emitted, if so, put a new entry into CRTable 654 * and call method to generate bytecode. 655 * If not, just call method to generate bytecode. 656 * @see #genStat(JCTree, Env) 657 * 658 * @param tree The tree to be visited. 659 * @param env The environment to use. 660 * @param crtFlags The CharacterRangeTable flags 661 * indicating type of the entry. 662 */ 663 public void genStat(JCTree tree, Env<GenContext> env, int crtFlags) { 664 if (!genCrt) { 665 genStat(tree, env); 666 return; 667 } 668 int startpc = code.curCP(); 669 genStat(tree, env); 670 if (tree.hasTag(Tag.BLOCK)) crtFlags |= CRT_BLOCK; 671 code.crt.put(tree, crtFlags, startpc, code.curCP()); 672 } 673 674 /** Derived visitor method: generate code for a statement. 675 */ 676 public void genStat(JCTree tree, Env<GenContext> env) { 677 if (code.isAlive()) { 678 code.statBegin(tree.pos); 679 genDef(tree, env); 680 } else if (env.info.isSwitch && tree.hasTag(VARDEF)) { 681 // variables whose declarations are in a switch 682 // can be used even if the decl is unreachable. 683 code.newLocal(((JCVariableDecl) tree).sym); 684 } 685 } 686 687 /** Derived visitor method: check whether CharacterRangeTable 688 * should be emitted, if so, put a new entry into CRTable 689 * and call method to generate bytecode. 690 * If not, just call method to generate bytecode. 691 * @see #genStats(List, Env) 692 * 693 * @param trees The list of trees to be visited. 694 * @param env The environment to use. 695 * @param crtFlags The CharacterRangeTable flags 696 * indicating type of the entry. 697 */ 698 public void genStats(List<JCStatement> trees, Env<GenContext> env, int crtFlags) { 699 if (!genCrt) { 700 genStats(trees, env); 701 return; 702 } 703 if (trees.length() == 1) { // mark one statement with the flags 704 genStat(trees.head, env, crtFlags | CRT_STATEMENT); 705 } else { 706 int startpc = code.curCP(); 707 genStats(trees, env); 708 code.crt.put(trees, crtFlags, startpc, code.curCP()); 709 } 710 } 711 712 /** Derived visitor method: generate code for a list of statements. 713 */ 714 public void genStats(List<? extends JCTree> trees, Env<GenContext> env) { 715 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail) 716 genStat(l.head, env, CRT_STATEMENT); 717 } 718 719 /** Derived visitor method: check whether CharacterRangeTable 720 * should be emitted, if so, put a new entry into CRTable 721 * and call method to generate bytecode. 722 * If not, just call method to generate bytecode. 723 * @see #genCond(JCTree,boolean) 724 * 725 * @param tree The tree to be visited. 726 * @param crtFlags The CharacterRangeTable flags 727 * indicating type of the entry. 728 */ 729 public CondItem genCond(JCTree tree, int crtFlags) { 730 if (!genCrt) return genCond(tree, false); 731 int startpc = code.curCP(); 732 CondItem item = genCond(tree, (crtFlags & CRT_FLOW_CONTROLLER) != 0); 733 code.crt.put(tree, crtFlags, startpc, code.curCP()); 734 return item; 735 } 736 737 /** Derived visitor method: generate code for a boolean 738 * expression in a control-flow context. 739 * @param _tree The expression to be visited. 740 * @param markBranches The flag to indicate that the condition is 741 * a flow controller so produced conditions 742 * should contain a proper tree to generate 743 * CharacterRangeTable branches for them. 744 */ 745 public CondItem genCond(JCTree _tree, boolean markBranches) { 746 JCTree inner_tree = TreeInfo.skipParens(_tree); 747 if (inner_tree.hasTag(CONDEXPR)) { 748 JCConditional tree = (JCConditional)inner_tree; 749 CondItem cond = genCond(tree.cond, CRT_FLOW_CONTROLLER); 750 if (cond.isTrue()) { 751 code.resolve(cond.trueJumps); 752 CondItem result = genCond(tree.truepart, CRT_FLOW_TARGET); 753 if (markBranches) result.tree = tree.truepart; 754 return result; 755 } 756 if (cond.isFalse()) { 757 code.resolve(cond.falseJumps); 758 CondItem result = genCond(tree.falsepart, CRT_FLOW_TARGET); 759 if (markBranches) result.tree = tree.falsepart; 760 return result; 761 } 762 Chain secondJumps = cond.jumpFalse(); 763 code.resolve(cond.trueJumps); 764 CondItem first = genCond(tree.truepart, CRT_FLOW_TARGET); 765 if (markBranches) first.tree = tree.truepart; 766 Chain falseJumps = first.jumpFalse(); 767 code.resolve(first.trueJumps); 768 Chain trueJumps = code.branch(goto_); 769 code.resolve(secondJumps); 770 CondItem second = genCond(tree.falsepart, CRT_FLOW_TARGET); 771 CondItem result = items.makeCondItem(second.opcode, 772 Code.mergeChains(trueJumps, second.trueJumps), 773 Code.mergeChains(falseJumps, second.falseJumps)); 774 if (markBranches) result.tree = tree.falsepart; 775 return result; 776 } else if (inner_tree.hasTag(SWITCH_EXPRESSION)) { 777 code.resolvePending(); 778 779 boolean prevInCondSwitchExpression = inCondSwitchExpression; 780 Chain prevSwitchExpressionTrueChain = switchExpressionTrueChain; 781 Chain prevSwitchExpressionFalseChain = switchExpressionFalseChain; 782 try { 783 inCondSwitchExpression = true; 784 switchExpressionTrueChain = null; 785 switchExpressionFalseChain = null; 786 try { 787 doHandleSwitchExpression((JCSwitchExpression) inner_tree); 788 } catch (CompletionFailure ex) { 789 chk.completionError(_tree.pos(), ex); 790 code.state.stacksize = 1; 791 } 792 CondItem result = items.makeCondItem(goto_, 793 switchExpressionTrueChain, 794 switchExpressionFalseChain); 795 if (markBranches) result.tree = _tree; 796 return result; 797 } finally { 798 inCondSwitchExpression = prevInCondSwitchExpression; 799 switchExpressionTrueChain = prevSwitchExpressionTrueChain; 800 switchExpressionFalseChain = prevSwitchExpressionFalseChain; 801 } 802 } else if (inner_tree.hasTag(LETEXPR) && ((LetExpr) inner_tree).needsCond) { 803 code.resolvePending(); 804 805 LetExpr tree = (LetExpr) inner_tree; 806 int limit = code.nextreg; 807 int prevLetExprStart = code.setLetExprStackPos(code.state.stacksize); 808 try { 809 genStats(tree.defs, env); 810 } finally { 811 code.setLetExprStackPos(prevLetExprStart); 812 } 813 CondItem result = genCond(tree.expr, markBranches); 814 code.endScopes(limit); 815 return result; 816 } else { 817 CondItem result = genExpr(_tree, syms.booleanType).mkCond(); 818 if (markBranches) result.tree = _tree; 819 return result; 820 } 821 } 822 823 public Code getCode() { 824 return code; 825 } 826 827 public Items getItems() { 828 return items; 829 } 830 831 public Env<AttrContext> getAttrEnv() { 832 return attrEnv; 833 } 834 835 /** Visitor class for expressions which might be constant expressions. 836 * This class is a subset of TreeScanner. Intended to visit trees pruned by 837 * Lower as long as constant expressions looking for references to any 838 * ClassSymbol. Any such reference will be added to the constant pool so 839 * automated tools can detect class dependencies better. 840 */ 841 class ClassReferenceVisitor extends JCTree.Visitor { 842 843 @Override 844 public void visitTree(JCTree tree) {} 845 846 @Override 847 public void visitBinary(JCBinary tree) { 848 tree.lhs.accept(this); 849 tree.rhs.accept(this); 850 } 851 852 @Override 853 public void visitSelect(JCFieldAccess tree) { 854 if (tree.selected.type.hasTag(CLASS)) { 855 makeRef(tree.selected.pos(), tree.selected.type); 856 } 857 } 858 859 @Override 860 public void visitIdent(JCIdent tree) { 861 if (tree.sym.owner instanceof ClassSymbol classSymbol) { 862 poolWriter.putClass(classSymbol); 863 } 864 } 865 866 @Override 867 public void visitConditional(JCConditional tree) { 868 tree.cond.accept(this); 869 tree.truepart.accept(this); 870 tree.falsepart.accept(this); 871 } 872 873 @Override 874 public void visitUnary(JCUnary tree) { 875 tree.arg.accept(this); 876 } 877 878 @Override 879 public void visitParens(JCParens tree) { 880 tree.expr.accept(this); 881 } 882 883 @Override 884 public void visitTypeCast(JCTypeCast tree) { 885 tree.expr.accept(this); 886 } 887 } 888 889 private ClassReferenceVisitor classReferenceVisitor = new ClassReferenceVisitor(); 890 891 /** Visitor method: generate code for an expression, catching and reporting 892 * any completion failures. 893 * @param tree The expression to be visited. 894 * @param pt The expression's expected type (proto-type). 895 */ 896 public Item genExpr(JCTree tree, Type pt) { 897 if (!code.isAlive()) { 898 return items.makeStackItem(pt); 899 } 900 901 Type prevPt = this.pt; 902 try { 903 if (tree.type.constValue() != null) { 904 // Short circuit any expressions which are constants 905 tree.accept(classReferenceVisitor); 906 checkStringConstant(tree.pos(), tree.type.constValue()); 907 Symbol sym = TreeInfo.symbol(tree); 908 if (sym != null && isConstantDynamic(sym)) { 909 result = items.makeDynamicItem(sym); 910 } else { 911 result = items.makeImmediateItem(tree.type, tree.type.constValue()); 912 } 913 } else { 914 this.pt = pt; 915 tree.accept(this); 916 } 917 return result.coerce(pt); 918 } catch (CompletionFailure ex) { 919 chk.completionError(tree.pos(), ex); 920 code.state.stacksize = 1; 921 return items.makeStackItem(pt); 922 } finally { 923 this.pt = prevPt; 924 } 925 } 926 927 public boolean isConstantDynamic(Symbol sym) { 928 return sym.kind == VAR && 929 sym instanceof DynamicVarSymbol dynamicVarSymbol && 930 dynamicVarSymbol.isDynamic(); 931 } 932 933 /** Derived visitor method: generate code for a list of method arguments. 934 * @param trees The argument expressions to be visited. 935 * @param pts The expression's expected types (i.e. the formal parameter 936 * types of the invoked method). 937 */ 938 public void genArgs(List<JCExpression> trees, List<Type> pts) { 939 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail) { 940 genExpr(l.head, pts.head).load(); 941 pts = pts.tail; 942 } 943 // require lists be of same length 944 Assert.check(pts.isEmpty()); 945 } 946 947 /* ************************************************************************ 948 * Visitor methods for statements and definitions 949 *************************************************************************/ 950 951 /** Thrown when the byte code size exceeds limit. 952 */ 953 public static class CodeSizeOverflow extends RuntimeException { 954 private static final long serialVersionUID = 0; 955 public CodeSizeOverflow() {} 956 } 957 958 public void visitMethodDef(JCMethodDecl tree) { 959 // Create a new local environment that points pack at method 960 // definition. 961 Env<GenContext> localEnv = env.dup(tree); 962 localEnv.enclMethod = tree; 963 // The expected type of every return statement in this method 964 // is the method's return type. 965 this.pt = tree.sym.erasure(types).getReturnType(); 966 967 checkDimension(tree.pos(), tree.sym.erasure(types)); 968 genMethod(tree, localEnv, false); 969 } 970 //where 971 /** Generate code for a method. 972 * @param tree The tree representing the method definition. 973 * @param env The environment current for the method body. 974 * @param fatcode A flag that indicates whether all jumps are 975 * within 32K. We first invoke this method under 976 * the assumption that fatcode == false, i.e. all 977 * jumps are within 32K. If this fails, fatcode 978 * is set to true and we try again. 979 */ 980 void genMethod(JCMethodDecl tree, Env<GenContext> env, boolean fatcode) { 981 MethodSymbol meth = tree.sym; 982 int extras = 0; 983 // Count up extra parameters 984 if (meth.isConstructor()) { 985 extras++; 986 if (meth.enclClass().isInner() && 987 !meth.enclClass().isStatic()) { 988 extras++; 989 } 990 } else if ((tree.mods.flags & STATIC) == 0) { 991 extras++; 992 } 993 // System.err.println("Generating " + meth + " in " + meth.owner); //DEBUG 994 if (Code.width(types.erasure(env.enclMethod.sym.type).getParameterTypes()) + extras > 995 ClassFile.MAX_PARAMETERS) { 996 log.error(tree.pos(), Errors.LimitParameters); 997 nerrs++; 998 } 999 1000 else if (tree.body != null) { 1001 // Create a new code structure and initialize it. 1002 int startpcCrt = initCode(tree, env, fatcode); 1003 Set<VarSymbol> prevUnsetFields = code.currentUnsetFields; 1004 if (meth.isConstructor()) { 1005 code.currentUnsetFields = unsetFieldsInfo.getUnsetFields(env.enclClass.sym, tree.body); 1006 code.initialUnsetFields = unsetFieldsInfo.getUnsetFields(env.enclClass.sym, tree.body); 1007 } 1008 1009 try { 1010 genStat(tree.body, env); 1011 } catch (CodeSizeOverflow e) { 1012 // Failed due to code limit, try again with jsr/ret 1013 startpcCrt = initCode(tree, env, fatcode); 1014 genStat(tree.body, env); 1015 } finally { 1016 code.currentUnsetFields = prevUnsetFields; 1017 } 1018 1019 if (code.state.stacksize != 0) { 1020 log.error(tree.body.pos(), Errors.StackSimError(tree.sym)); 1021 throw new AssertionError(); 1022 } 1023 1024 // If last statement could complete normally, insert a 1025 // return at the end. 1026 if (code.isAlive()) { 1027 code.statBegin(TreeInfo.endPos(tree.body)); 1028 if (env.enclMethod == null || 1029 env.enclMethod.sym.type.getReturnType().hasTag(VOID)) { 1030 code.emitop0(return_); 1031 } else { 1032 // sometime dead code seems alive (4415991); 1033 // generate a small loop instead 1034 int startpc = code.entryPoint(); 1035 CondItem c = items.makeCondItem(goto_); 1036 code.resolve(c.jumpTrue(), startpc); 1037 } 1038 } 1039 if (genCrt) 1040 code.crt.put(tree.body, 1041 CRT_BLOCK, 1042 startpcCrt, 1043 code.curCP()); 1044 1045 code.endScopes(0); 1046 1047 // If we exceeded limits, panic 1048 if (code.checkLimits(tree.pos(), log)) { 1049 nerrs++; 1050 return; 1051 } 1052 1053 // If we generated short code but got a long jump, do it again 1054 // with fatCode = true. 1055 if (!fatcode && code.fatcode) genMethod(tree, env, true); 1056 1057 // Clean up 1058 if(stackMap == StackMapFormat.JSR202) { 1059 code.lastFrame = null; 1060 code.frameBeforeLast = null; 1061 } 1062 1063 // Compress exception table 1064 code.compressCatchTable(); 1065 1066 // Fill in type annotation positions for exception parameters 1067 code.fillExceptionParameterPositions(); 1068 } 1069 } 1070 1071 private int initCode(JCMethodDecl tree, Env<GenContext> env, boolean fatcode) { 1072 MethodSymbol meth = tree.sym; 1073 1074 // Create a new code structure. 1075 meth.code = code = new Code(meth, 1076 fatcode, 1077 lineDebugInfo ? toplevel.lineMap : null, 1078 varDebugInfo, 1079 stackMap, 1080 debugCode, 1081 genCrt ? new CRTable(tree, env.toplevel.endPositions) 1082 : null, 1083 syms, 1084 types, 1085 poolWriter, 1086 generateEarlyLarvalFrame); 1087 items = new Items(poolWriter, code, syms, types); 1088 if (code.debugCode) { 1089 System.err.println(meth + " for body " + tree); 1090 } 1091 1092 // If method is not static, create a new local variable address 1093 // for `this'. 1094 if ((tree.mods.flags & STATIC) == 0) { 1095 Type selfType = meth.owner.type; 1096 if (meth.isConstructor() && selfType != syms.objectType) 1097 selfType = UninitializedType.uninitializedThis(selfType); 1098 code.setDefined( 1099 code.newLocal( 1100 new VarSymbol(FINAL, names._this, selfType, meth.owner))); 1101 } 1102 1103 // Mark all parameters as defined from the beginning of 1104 // the method. 1105 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) { 1106 checkDimension(l.head.pos(), l.head.sym.type); 1107 code.setDefined(code.newLocal(l.head.sym)); 1108 } 1109 1110 // Get ready to generate code for method body. 1111 int startpcCrt = genCrt ? code.curCP() : 0; 1112 code.entryPoint(); 1113 1114 // Suppress initial stackmap 1115 code.pendingStackMap = false; 1116 1117 return startpcCrt; 1118 } 1119 1120 public void visitVarDef(JCVariableDecl tree) { 1121 VarSymbol v = tree.sym; 1122 if (tree.init != null) { 1123 checkStringConstant(tree.init.pos(), v.getConstValue()); 1124 if (v.getConstValue() == null || varDebugInfo) { 1125 Assert.check(code.isStatementStart()); 1126 code.newLocal(v); 1127 genExpr(tree.init, v.erasure(types)).load(); 1128 items.makeLocalItem(v).store(); 1129 Assert.check(code.isStatementStart()); 1130 } 1131 } else { 1132 code.newLocal(v); 1133 } 1134 checkDimension(tree.pos(), v.type); 1135 } 1136 1137 public void visitSkip(JCSkip tree) { 1138 } 1139 1140 public void visitBlock(JCBlock tree) { 1141 /* this method is heavily invoked, as expected, for deeply nested blocks, if blocks doesn't happen to have 1142 * patterns there will be an unnecessary tax on memory consumption every time this method is executed, for this 1143 * reason we have created helper methods and here at a higher level we just discriminate depending on the 1144 * presence, or not, of patterns in a given block 1145 */ 1146 if (tree.patternMatchingCatch != null) { 1147 visitBlockWithPatterns(tree); 1148 } else { 1149 internalVisitBlock(tree); 1150 } 1151 } 1152 1153 private void visitBlockWithPatterns(JCBlock tree) { 1154 PatternMatchingCatchConfiguration prevConfiguration = patternMatchingCatchConfiguration; 1155 try { 1156 patternMatchingCatchConfiguration = 1157 new PatternMatchingCatchConfiguration(tree.patternMatchingCatch.calls2Handle(), 1158 new ListBuffer<int[]>(), 1159 tree.patternMatchingCatch.handler(), 1160 code.state.dup()); 1161 internalVisitBlock(tree); 1162 } finally { 1163 generatePatternMatchingCatch(env); 1164 patternMatchingCatchConfiguration = prevConfiguration; 1165 } 1166 } 1167 1168 private void generatePatternMatchingCatch(Env<GenContext> env) { 1169 if (patternMatchingCatchConfiguration.handler != null && 1170 !patternMatchingCatchConfiguration.ranges.isEmpty()) { 1171 Chain skipCatch = code.branch(goto_); 1172 JCCatch handler = patternMatchingCatchConfiguration.handler(); 1173 code.entryPoint(patternMatchingCatchConfiguration.startState(), 1174 handler.param.sym.type); 1175 genPatternMatchingCatch(handler, 1176 env, 1177 patternMatchingCatchConfiguration.ranges.toList()); 1178 code.resolve(skipCatch); 1179 } 1180 } 1181 1182 private void internalVisitBlock(JCBlock tree) { 1183 int limit = code.nextreg; 1184 Env<GenContext> localEnv = env.dup(tree, new GenContext()); 1185 genStats(tree.stats, localEnv); 1186 // End the scope of all block-local variables in variable info. 1187 if (!env.tree.hasTag(METHODDEF)) { 1188 code.statBegin(tree.endpos); 1189 code.endScopes(limit); 1190 code.pendingStatPos = Position.NOPOS; 1191 } 1192 } 1193 1194 public void visitDoLoop(JCDoWhileLoop tree) { 1195 genLoop(tree, tree.body, tree.cond, List.nil(), false); 1196 } 1197 1198 public void visitWhileLoop(JCWhileLoop tree) { 1199 genLoop(tree, tree.body, tree.cond, List.nil(), true); 1200 } 1201 1202 public void visitForLoop(JCForLoop tree) { 1203 int limit = code.nextreg; 1204 genStats(tree.init, env); 1205 genLoop(tree, tree.body, tree.cond, tree.step, true); 1206 code.endScopes(limit); 1207 } 1208 //where 1209 /** Generate code for a loop. 1210 * @param loop The tree representing the loop. 1211 * @param body The loop's body. 1212 * @param cond The loop's controlling condition. 1213 * @param step "Step" statements to be inserted at end of 1214 * each iteration. 1215 * @param testFirst True if the loop test belongs before the body. 1216 */ 1217 private void genLoop(JCStatement loop, 1218 JCStatement body, 1219 JCExpression cond, 1220 List<JCExpressionStatement> step, 1221 boolean testFirst) { 1222 Set<VarSymbol> prevCodeUnsetFields = code.currentUnsetFields; 1223 try { 1224 genLoopHelper(loop, body, cond, step, testFirst); 1225 } finally { 1226 code.currentUnsetFields = prevCodeUnsetFields; 1227 } 1228 } 1229 1230 private void genLoopHelper(JCStatement loop, 1231 JCStatement body, 1232 JCExpression cond, 1233 List<JCExpressionStatement> step, 1234 boolean testFirst) { 1235 Env<GenContext> loopEnv = env.dup(loop, new GenContext()); 1236 int startpc = code.entryPoint(); 1237 if (testFirst) { //while or for loop 1238 CondItem c; 1239 if (cond != null) { 1240 code.statBegin(cond.pos); 1241 Assert.check(code.isStatementStart()); 1242 c = genCond(TreeInfo.skipParens(cond), CRT_FLOW_CONTROLLER); 1243 } else { 1244 c = items.makeCondItem(goto_); 1245 } 1246 Chain loopDone = c.jumpFalse(); 1247 code.resolve(c.trueJumps); 1248 Assert.check(code.isStatementStart()); 1249 genStat(body, loopEnv, CRT_STATEMENT | CRT_FLOW_TARGET); 1250 code.resolve(loopEnv.info.cont); 1251 genStats(step, loopEnv); 1252 code.resolve(code.branch(goto_), startpc); 1253 code.resolve(loopDone); 1254 } else { 1255 genStat(body, loopEnv, CRT_STATEMENT | CRT_FLOW_TARGET); 1256 code.resolve(loopEnv.info.cont); 1257 genStats(step, loopEnv); 1258 if (code.isAlive()) { 1259 CondItem c; 1260 if (cond != null) { 1261 code.statBegin(cond.pos); 1262 Assert.check(code.isStatementStart()); 1263 c = genCond(TreeInfo.skipParens(cond), CRT_FLOW_CONTROLLER); 1264 } else { 1265 c = items.makeCondItem(goto_); 1266 } 1267 code.resolve(c.jumpTrue(), startpc); 1268 Assert.check(code.isStatementStart()); 1269 code.resolve(c.falseJumps); 1270 } 1271 } 1272 Chain exit = loopEnv.info.exit; 1273 if (exit != null) { 1274 code.resolve(exit); 1275 exit.state.defined.excludeFrom(code.nextreg); 1276 } 1277 } 1278 1279 public void visitForeachLoop(JCEnhancedForLoop tree) { 1280 throw new AssertionError(); // should have been removed by Lower. 1281 } 1282 1283 public void visitLabelled(JCLabeledStatement tree) { 1284 Env<GenContext> localEnv = env.dup(tree, new GenContext()); 1285 genStat(tree.body, localEnv, CRT_STATEMENT); 1286 Chain exit = localEnv.info.exit; 1287 if (exit != null) { 1288 code.resolve(exit); 1289 exit.state.defined.excludeFrom(code.nextreg); 1290 } 1291 } 1292 1293 public void visitSwitch(JCSwitch tree) { 1294 handleSwitch(tree, tree.selector, tree.cases, tree.patternSwitch); 1295 } 1296 1297 @Override 1298 public void visitSwitchExpression(JCSwitchExpression tree) { 1299 code.resolvePending(); 1300 boolean prevInCondSwitchExpression = inCondSwitchExpression; 1301 Set<VarSymbol> prevCodeUnsetFields = code.currentUnsetFields; 1302 try { 1303 inCondSwitchExpression = false; 1304 doHandleSwitchExpression(tree); 1305 } finally { 1306 inCondSwitchExpression = prevInCondSwitchExpression; 1307 code.currentUnsetFields = prevCodeUnsetFields; 1308 } 1309 result = items.makeStackItem(pt); 1310 } 1311 1312 private void doHandleSwitchExpression(JCSwitchExpression tree) { 1313 List<LocalItem> prevStackBeforeSwitchExpression = stackBeforeSwitchExpression; 1314 LocalItem prevSwitchResult = switchResult; 1315 int limit = code.nextreg; 1316 try { 1317 stackBeforeSwitchExpression = List.nil(); 1318 switchResult = null; 1319 if (hasTry(tree)) { 1320 //if the switch expression contains try-catch, the catch handlers need to have 1321 //an empty stack. So stash whole stack to local variables, and restore it before 1322 //breaks: 1323 while (code.state.stacksize > 0) { 1324 Type type = code.state.peek(); 1325 Name varName = names.fromString(target.syntheticNameChar() + 1326 "stack" + 1327 target.syntheticNameChar() + 1328 tree.pos + 1329 target.syntheticNameChar() + 1330 code.state.stacksize); 1331 VarSymbol var = new VarSymbol(Flags.SYNTHETIC, varName, type, 1332 this.env.enclMethod.sym); 1333 LocalItem item = items.new LocalItem(type, code.newLocal(var)); 1334 stackBeforeSwitchExpression = stackBeforeSwitchExpression.prepend(item); 1335 item.store(); 1336 } 1337 switchResult = makeTemp(tree.type); 1338 } 1339 int prevLetExprStart = code.setLetExprStackPos(code.state.stacksize); 1340 try { 1341 handleSwitch(tree, tree.selector, tree.cases, tree.patternSwitch); 1342 } finally { 1343 code.setLetExprStackPos(prevLetExprStart); 1344 } 1345 } finally { 1346 stackBeforeSwitchExpression = prevStackBeforeSwitchExpression; 1347 switchResult = prevSwitchResult; 1348 code.endScopes(limit); 1349 } 1350 } 1351 //where: 1352 private boolean hasTry(JCSwitchExpression tree) { 1353 class HasTryScanner extends TreeScanner { 1354 private boolean hasTry; 1355 1356 @Override 1357 public void visitTry(JCTry tree) { 1358 hasTry = true; 1359 } 1360 1361 @Override 1362 public void visitSynchronized(JCSynchronized tree) { 1363 hasTry = true; 1364 } 1365 1366 @Override 1367 public void visitClassDef(JCClassDecl tree) { 1368 } 1369 1370 @Override 1371 public void visitLambda(JCLambda tree) { 1372 } 1373 }; 1374 1375 HasTryScanner hasTryScanner = new HasTryScanner(); 1376 1377 hasTryScanner.scan(tree); 1378 return hasTryScanner.hasTry; 1379 } 1380 1381 private void handleSwitch(JCTree swtch, JCExpression selector, List<JCCase> cases, 1382 boolean patternSwitch) { 1383 Set<VarSymbol> prevCodeUnsetFields = code.currentUnsetFields; 1384 try { 1385 handleSwitchHelper(swtch, selector, cases, patternSwitch); 1386 } finally { 1387 code.currentUnsetFields = prevCodeUnsetFields; 1388 } 1389 } 1390 1391 void handleSwitchHelper(JCTree swtch, JCExpression selector, List<JCCase> cases, 1392 boolean patternSwitch) { 1393 int limit = code.nextreg; 1394 Assert.check(!selector.type.hasTag(CLASS)); 1395 int switchStart = patternSwitch ? code.entryPoint() : -1; 1396 int startpcCrt = genCrt ? code.curCP() : 0; 1397 Assert.check(code.isStatementStart()); 1398 Item sel = genExpr(selector, syms.intType); 1399 if (cases.isEmpty()) { 1400 // We are seeing: switch <sel> {} 1401 sel.load().drop(); 1402 if (genCrt) 1403 code.crt.put(TreeInfo.skipParens(selector), 1404 CRT_FLOW_CONTROLLER, startpcCrt, code.curCP()); 1405 } else { 1406 // We are seeing a nonempty switch. 1407 sel.load(); 1408 if (genCrt) 1409 code.crt.put(TreeInfo.skipParens(selector), 1410 CRT_FLOW_CONTROLLER, startpcCrt, code.curCP()); 1411 Env<GenContext> switchEnv = env.dup(swtch, new GenContext()); 1412 switchEnv.info.isSwitch = true; 1413 1414 // Compute number of labels and minimum and maximum label values. 1415 // For each case, store its label in an array. 1416 int lo = Integer.MAX_VALUE; // minimum label. 1417 int hi = Integer.MIN_VALUE; // maximum label. 1418 int nlabels = 0; // number of labels. 1419 1420 int[] labels = new int[cases.length()]; // the label array. 1421 int defaultIndex = -1; // the index of the default clause. 1422 1423 List<JCCase> l = cases; 1424 for (int i = 0; i < labels.length; i++) { 1425 if (l.head.labels.head instanceof JCConstantCaseLabel constLabel) { 1426 Assert.check(l.head.labels.size() == 1); 1427 int val = ((Number) constLabel.expr.type.constValue()).intValue(); 1428 labels[i] = val; 1429 if (val < lo) lo = val; 1430 if (hi < val) hi = val; 1431 nlabels++; 1432 } else { 1433 Assert.check(defaultIndex == -1); 1434 defaultIndex = i; 1435 } 1436 l = l.tail; 1437 } 1438 1439 // Determine whether to issue a tableswitch or a lookupswitch 1440 // instruction. 1441 long table_space_cost = 4 + ((long) hi - lo + 1); // words 1442 long table_time_cost = 3; // comparisons 1443 long lookup_space_cost = 3 + 2 * (long) nlabels; 1444 long lookup_time_cost = nlabels; 1445 int opcode = 1446 nlabels > 0 && 1447 table_space_cost + 3 * table_time_cost <= 1448 lookup_space_cost + 3 * lookup_time_cost 1449 ? 1450 tableswitch : lookupswitch; 1451 1452 int startpc = code.curCP(); // the position of the selector operation 1453 code.emitop0(opcode); 1454 code.align(4); 1455 int tableBase = code.curCP(); // the start of the jump table 1456 int[] offsets = null; // a table of offsets for a lookupswitch 1457 code.emit4(-1); // leave space for default offset 1458 if (opcode == tableswitch) { 1459 code.emit4(lo); // minimum label 1460 code.emit4(hi); // maximum label 1461 for (long i = lo; i <= hi; i++) { // leave space for jump table 1462 code.emit4(-1); 1463 } 1464 } else { 1465 code.emit4(nlabels); // number of labels 1466 for (int i = 0; i < nlabels; i++) { 1467 code.emit4(-1); code.emit4(-1); // leave space for lookup table 1468 } 1469 offsets = new int[labels.length]; 1470 } 1471 Code.State stateSwitch = code.state.dup(); 1472 code.markDead(); 1473 1474 // For each case do: 1475 l = cases; 1476 for (int i = 0; i < labels.length; i++) { 1477 JCCase c = l.head; 1478 l = l.tail; 1479 1480 int pc = code.entryPoint(stateSwitch); 1481 // Insert offset directly into code or else into the 1482 // offsets table. 1483 if (i != defaultIndex) { 1484 if (opcode == tableswitch) { 1485 code.put4( 1486 tableBase + 4 * (labels[i] - lo + 3), 1487 pc - startpc); 1488 } else { 1489 offsets[i] = pc - startpc; 1490 } 1491 } else { 1492 code.put4(tableBase, pc - startpc); 1493 } 1494 1495 // Generate code for the statements in this case. 1496 genStats(c.stats, switchEnv, CRT_FLOW_TARGET); 1497 } 1498 1499 if (switchEnv.info.cont != null) { 1500 Assert.check(patternSwitch); 1501 code.resolve(switchEnv.info.cont, switchStart); 1502 } 1503 1504 // Resolve all breaks. 1505 Chain exit = switchEnv.info.exit; 1506 if (exit != null) { 1507 code.resolve(exit); 1508 exit.state.defined.excludeFrom(limit); 1509 } 1510 1511 // If we have not set the default offset, we do so now. 1512 if (code.get4(tableBase) == -1) { 1513 code.put4(tableBase, code.entryPoint(stateSwitch) - startpc); 1514 } 1515 1516 if (opcode == tableswitch) { 1517 // Let any unfilled slots point to the default case. 1518 int defaultOffset = code.get4(tableBase); 1519 for (long i = lo; i <= hi; i++) { 1520 int t = (int)(tableBase + 4 * (i - lo + 3)); 1521 if (code.get4(t) == -1) 1522 code.put4(t, defaultOffset); 1523 } 1524 } else { 1525 // Sort non-default offsets and copy into lookup table. 1526 if (defaultIndex >= 0) 1527 for (int i = defaultIndex; i < labels.length - 1; i++) { 1528 labels[i] = labels[i+1]; 1529 offsets[i] = offsets[i+1]; 1530 } 1531 if (nlabels > 0) 1532 qsort2(labels, offsets, 0, nlabels - 1); 1533 for (int i = 0; i < nlabels; i++) { 1534 int caseidx = tableBase + 8 * (i + 1); 1535 code.put4(caseidx, labels[i]); 1536 code.put4(caseidx + 4, offsets[i]); 1537 } 1538 } 1539 1540 if (swtch instanceof JCSwitchExpression) { 1541 // Emit line position for the end of a switch expression 1542 code.statBegin(TreeInfo.endPos(swtch)); 1543 } 1544 } 1545 code.endScopes(limit); 1546 } 1547 //where 1548 /** Sort (int) arrays of keys and values 1549 */ 1550 static void qsort2(int[] keys, int[] values, int lo, int hi) { 1551 int i = lo; 1552 int j = hi; 1553 int pivot = keys[(i+j)/2]; 1554 do { 1555 while (keys[i] < pivot) i++; 1556 while (pivot < keys[j]) j--; 1557 if (i <= j) { 1558 int temp1 = keys[i]; 1559 keys[i] = keys[j]; 1560 keys[j] = temp1; 1561 int temp2 = values[i]; 1562 values[i] = values[j]; 1563 values[j] = temp2; 1564 i++; 1565 j--; 1566 } 1567 } while (i <= j); 1568 if (lo < j) qsort2(keys, values, lo, j); 1569 if (i < hi) qsort2(keys, values, i, hi); 1570 } 1571 1572 public void visitSynchronized(JCSynchronized tree) { 1573 int limit = code.nextreg; 1574 // Generate code to evaluate lock and save in temporary variable. 1575 final LocalItem lockVar = makeTemp(syms.objectType); 1576 Assert.check(code.isStatementStart()); 1577 genExpr(tree.lock, tree.lock.type).load().duplicate(); 1578 lockVar.store(); 1579 1580 // Generate code to enter monitor. 1581 code.emitop0(monitorenter); 1582 code.state.lock(lockVar.reg); 1583 1584 // Generate code for a try statement with given body, no catch clauses 1585 // in a new environment with the "exit-monitor" operation as finalizer. 1586 final Env<GenContext> syncEnv = env.dup(tree, new GenContext()); 1587 syncEnv.info.finalize = new GenFinalizer() { 1588 void gen() { 1589 genLast(); 1590 Assert.check(syncEnv.info.gaps.length() % 2 == 0); 1591 syncEnv.info.gaps.append(code.curCP()); 1592 } 1593 void genLast() { 1594 if (code.isAlive()) { 1595 lockVar.load(); 1596 code.emitop0(monitorexit); 1597 code.state.unlock(lockVar.reg); 1598 } 1599 } 1600 }; 1601 syncEnv.info.gaps = new ListBuffer<>(); 1602 genTry(tree.body, List.nil(), syncEnv); 1603 code.endScopes(limit); 1604 } 1605 1606 public void visitTry(final JCTry tree) { 1607 // Generate code for a try statement with given body and catch clauses, 1608 // in a new environment which calls the finally block if there is one. 1609 final Env<GenContext> tryEnv = env.dup(tree, new GenContext()); 1610 final Env<GenContext> oldEnv = env; 1611 tryEnv.info.finalize = new GenFinalizer() { 1612 void gen() { 1613 Assert.check(tryEnv.info.gaps.length() % 2 == 0); 1614 tryEnv.info.gaps.append(code.curCP()); 1615 genLast(); 1616 } 1617 void genLast() { 1618 if (tree.finalizer != null) 1619 genStat(tree.finalizer, oldEnv, CRT_BLOCK); 1620 } 1621 boolean hasFinalizer() { 1622 return tree.finalizer != null; 1623 } 1624 1625 @Override 1626 void afterBody() { 1627 if (tree.finalizer != null && (tree.finalizer.flags & BODY_ONLY_FINALIZE) != 0) { 1628 //for body-only finally, remove the GenFinalizer after try body 1629 //so that the finally is not generated to catch bodies: 1630 tryEnv.info.finalize = null; 1631 } 1632 } 1633 1634 }; 1635 tryEnv.info.gaps = new ListBuffer<>(); 1636 genTry(tree.body, tree.catchers, tryEnv); 1637 } 1638 //where 1639 /** Generate code for a try or synchronized statement 1640 * @param body The body of the try or synchronized statement. 1641 * @param catchers The list of catch clauses. 1642 * @param env The current environment of the body. 1643 */ 1644 void genTry(JCTree body, List<JCCatch> catchers, Env<GenContext> env) { 1645 Set<VarSymbol> prevCodeUnsetFields = code.currentUnsetFields; 1646 try { 1647 genTryHelper(body, catchers, env); 1648 } finally { 1649 code.currentUnsetFields = prevCodeUnsetFields; 1650 } 1651 } 1652 1653 void genTryHelper(JCTree body, List<JCCatch> catchers, Env<GenContext> env) { 1654 int limit = code.nextreg; 1655 int startpc = code.curCP(); 1656 Code.State stateTry = code.state.dup(); 1657 genStat(body, env, CRT_BLOCK); 1658 int endpc = code.curCP(); 1659 List<Integer> gaps = env.info.gaps.toList(); 1660 code.statBegin(TreeInfo.endPos(body)); 1661 genFinalizer(env); 1662 code.statBegin(TreeInfo.endPos(env.tree)); 1663 Chain exitChain; 1664 boolean actualTry = env.tree.hasTag(TRY); 1665 if (startpc == endpc && actualTry) { 1666 exitChain = code.branch(dontgoto); 1667 } else { 1668 exitChain = code.branch(goto_); 1669 } 1670 endFinalizerGap(env); 1671 env.info.finalize.afterBody(); 1672 boolean hasFinalizer = 1673 env.info.finalize != null && 1674 env.info.finalize.hasFinalizer(); 1675 if (startpc != endpc) for (List<JCCatch> l = catchers; l.nonEmpty(); l = l.tail) { 1676 // start off with exception on stack 1677 code.entryPoint(stateTry, l.head.param.sym.type); 1678 genCatch(l.head, env, startpc, endpc, gaps); 1679 genFinalizer(env); 1680 if (hasFinalizer || l.tail.nonEmpty()) { 1681 code.statBegin(TreeInfo.endPos(env.tree)); 1682 exitChain = Code.mergeChains(exitChain, 1683 code.branch(goto_)); 1684 } 1685 endFinalizerGap(env); 1686 } 1687 if (hasFinalizer && (startpc != endpc || !actualTry)) { 1688 // Create a new register segment to avoid allocating 1689 // the same variables in finalizers and other statements. 1690 code.newRegSegment(); 1691 1692 // Add a catch-all clause. 1693 1694 // start off with exception on stack 1695 int catchallpc = code.entryPoint(stateTry, syms.throwableType); 1696 1697 // Register all exception ranges for catch all clause. 1698 // The range of the catch all clause is from the beginning 1699 // of the try or synchronized block until the present 1700 // code pointer excluding all gaps in the current 1701 // environment's GenContext. 1702 int startseg = startpc; 1703 while (env.info.gaps.nonEmpty()) { 1704 int endseg = env.info.gaps.next().intValue(); 1705 registerCatch(body.pos(), startseg, endseg, 1706 catchallpc, 0); 1707 startseg = env.info.gaps.next().intValue(); 1708 } 1709 code.statBegin(TreeInfo.finalizerPos(env.tree, PosKind.FIRST_STAT_POS)); 1710 code.markStatBegin(); 1711 1712 Item excVar = makeTemp(syms.throwableType); 1713 excVar.store(); 1714 genFinalizer(env); 1715 code.resolvePending(); 1716 code.statBegin(TreeInfo.finalizerPos(env.tree, PosKind.END_POS)); 1717 code.markStatBegin(); 1718 1719 excVar.load(); 1720 registerCatch(body.pos(), startseg, 1721 env.info.gaps.next().intValue(), 1722 catchallpc, 0); 1723 code.emitop0(athrow); 1724 code.markDead(); 1725 1726 // If there are jsr's to this finalizer, ... 1727 if (env.info.cont != null) { 1728 // Resolve all jsr's. 1729 code.resolve(env.info.cont); 1730 1731 // Mark statement line number 1732 code.statBegin(TreeInfo.finalizerPos(env.tree, PosKind.FIRST_STAT_POS)); 1733 code.markStatBegin(); 1734 1735 // Save return address. 1736 LocalItem retVar = makeTemp(syms.throwableType); 1737 retVar.store(); 1738 1739 // Generate finalizer code. 1740 env.info.finalize.genLast(); 1741 1742 // Return. 1743 code.emitop1w(ret, retVar.reg); 1744 code.markDead(); 1745 } 1746 } 1747 // Resolve all breaks. 1748 code.resolve(exitChain); 1749 1750 code.endScopes(limit); 1751 } 1752 1753 /** Generate code for a catch clause. 1754 * @param tree The catch clause. 1755 * @param env The environment current in the enclosing try. 1756 * @param startpc Start pc of try-block. 1757 * @param endpc End pc of try-block. 1758 */ 1759 void genCatch(JCCatch tree, 1760 Env<GenContext> env, 1761 int startpc, int endpc, 1762 List<Integer> gaps) { 1763 if (startpc != endpc) { 1764 List<Pair<List<Attribute.TypeCompound>, JCExpression>> catchTypeExprs 1765 = catchTypesWithAnnotations(tree); 1766 while (gaps.nonEmpty()) { 1767 for (Pair<List<Attribute.TypeCompound>, JCExpression> subCatch1 : catchTypeExprs) { 1768 JCExpression subCatch = subCatch1.snd; 1769 int catchType = makeRef(tree.pos(), subCatch.type); 1770 int end = gaps.head.intValue(); 1771 registerCatch(tree.pos(), 1772 startpc, end, code.curCP(), 1773 catchType); 1774 for (Attribute.TypeCompound tc : subCatch1.fst) { 1775 tc.position.setCatchInfo(catchType, startpc); 1776 } 1777 } 1778 gaps = gaps.tail; 1779 startpc = gaps.head.intValue(); 1780 gaps = gaps.tail; 1781 } 1782 if (startpc < endpc) { 1783 for (Pair<List<Attribute.TypeCompound>, JCExpression> subCatch1 : catchTypeExprs) { 1784 JCExpression subCatch = subCatch1.snd; 1785 int catchType = makeRef(tree.pos(), subCatch.type); 1786 registerCatch(tree.pos(), 1787 startpc, endpc, code.curCP(), 1788 catchType); 1789 for (Attribute.TypeCompound tc : subCatch1.fst) { 1790 tc.position.setCatchInfo(catchType, startpc); 1791 } 1792 } 1793 } 1794 genCatchBlock(tree, env); 1795 } 1796 } 1797 void genPatternMatchingCatch(JCCatch tree, 1798 Env<GenContext> env, 1799 List<int[]> ranges) { 1800 for (int[] range : ranges) { 1801 JCExpression subCatch = tree.param.vartype; 1802 int catchType = makeRef(tree.pos(), subCatch.type); 1803 registerCatch(tree.pos(), 1804 range[0], range[1], code.curCP(), 1805 catchType); 1806 } 1807 genCatchBlock(tree, env); 1808 } 1809 void genCatchBlock(JCCatch tree, Env<GenContext> env) { 1810 VarSymbol exparam = tree.param.sym; 1811 code.statBegin(tree.pos); 1812 code.markStatBegin(); 1813 int limit = code.nextreg; 1814 code.newLocal(exparam); 1815 items.makeLocalItem(exparam).store(); 1816 code.statBegin(TreeInfo.firstStatPos(tree.body)); 1817 genStat(tree.body, env, CRT_BLOCK); 1818 code.endScopes(limit); 1819 code.statBegin(TreeInfo.endPos(tree.body)); 1820 } 1821 // where 1822 List<Pair<List<Attribute.TypeCompound>, JCExpression>> catchTypesWithAnnotations(JCCatch tree) { 1823 return TreeInfo.isMultiCatch(tree) ? 1824 catchTypesWithAnnotationsFromMulticatch((JCTypeUnion)tree.param.vartype, tree.param.sym.getRawTypeAttributes()) : 1825 List.of(new Pair<>(tree.param.sym.getRawTypeAttributes(), tree.param.vartype)); 1826 } 1827 // where 1828 List<Pair<List<Attribute.TypeCompound>, JCExpression>> catchTypesWithAnnotationsFromMulticatch(JCTypeUnion tree, List<TypeCompound> first) { 1829 List<JCExpression> alts = tree.alternatives; 1830 List<Pair<List<TypeCompound>, JCExpression>> res = List.of(new Pair<>(first, alts.head)); 1831 alts = alts.tail; 1832 1833 while(alts != null && alts.head != null) { 1834 JCExpression alt = alts.head; 1835 if (alt instanceof JCAnnotatedType annotatedType) { 1836 res = res.prepend(new Pair<>(annotate.fromAnnotations(annotatedType.annotations), alt)); 1837 } else { 1838 res = res.prepend(new Pair<>(List.nil(), alt)); 1839 } 1840 alts = alts.tail; 1841 } 1842 return res.reverse(); 1843 } 1844 1845 /** Register a catch clause in the "Exceptions" code-attribute. 1846 */ 1847 void registerCatch(DiagnosticPosition pos, 1848 int startpc, int endpc, 1849 int handler_pc, int catch_type) { 1850 char startpc1 = (char)startpc; 1851 char endpc1 = (char)endpc; 1852 char handler_pc1 = (char)handler_pc; 1853 if (startpc1 == startpc && 1854 endpc1 == endpc && 1855 handler_pc1 == handler_pc) { 1856 code.addCatch(startpc1, endpc1, handler_pc1, 1857 (char)catch_type); 1858 } else { 1859 log.error(pos, Errors.LimitCodeTooLargeForTryStmt); 1860 nerrs++; 1861 } 1862 } 1863 1864 public void visitIf(JCIf tree) { 1865 Set<VarSymbol> prevCodeUnsetFields = code.currentUnsetFields; 1866 try { 1867 visitIfHelper(tree); 1868 } finally { 1869 code.currentUnsetFields = prevCodeUnsetFields; 1870 } 1871 } 1872 1873 public void visitIfHelper(JCIf tree) { 1874 int limit = code.nextreg; 1875 Chain thenExit = null; 1876 Assert.check(code.isStatementStart()); 1877 CondItem c = genCond(TreeInfo.skipParens(tree.cond), 1878 CRT_FLOW_CONTROLLER); 1879 Chain elseChain = c.jumpFalse(); 1880 Assert.check(code.isStatementStart()); 1881 if (!c.isFalse()) { 1882 code.resolve(c.trueJumps); 1883 genStat(tree.thenpart, env, CRT_STATEMENT | CRT_FLOW_TARGET); 1884 thenExit = code.branch(goto_); 1885 } 1886 if (elseChain != null) { 1887 code.resolve(elseChain); 1888 if (tree.elsepart != null) { 1889 genStat(tree.elsepart, env,CRT_STATEMENT | CRT_FLOW_TARGET); 1890 } 1891 } 1892 code.resolve(thenExit); 1893 code.endScopes(limit); 1894 Assert.check(code.isStatementStart()); 1895 } 1896 1897 public void visitExec(JCExpressionStatement tree) { 1898 // Optimize x++ to ++x and x-- to --x. 1899 JCExpression e = tree.expr; 1900 switch (e.getTag()) { 1901 case POSTINC: 1902 ((JCUnary) e).setTag(PREINC); 1903 break; 1904 case POSTDEC: 1905 ((JCUnary) e).setTag(PREDEC); 1906 break; 1907 } 1908 Assert.check(code.isStatementStart()); 1909 genExpr(tree.expr, tree.expr.type).drop(); 1910 Assert.check(code.isStatementStart()); 1911 } 1912 1913 public void visitBreak(JCBreak tree) { 1914 Assert.check(code.isStatementStart()); 1915 final Env<GenContext> targetEnv = unwindBreak(tree.target); 1916 targetEnv.info.addExit(code.branch(goto_)); 1917 endFinalizerGaps(env, targetEnv); 1918 } 1919 1920 public void visitYield(JCYield tree) { 1921 Assert.check(code.isStatementStart()); 1922 final Env<GenContext> targetEnv; 1923 if (inCondSwitchExpression) { 1924 CondItem value = genCond(tree.value, CRT_FLOW_TARGET); 1925 Chain falseJumps = value.jumpFalse(); 1926 1927 code.resolve(value.trueJumps); 1928 Env<GenContext> localEnv = unwindBreak(tree.target); 1929 reloadStackBeforeSwitchExpr(); 1930 Chain trueJumps = code.branch(goto_); 1931 1932 endFinalizerGaps(env, localEnv); 1933 1934 code.resolve(falseJumps); 1935 targetEnv = unwindBreak(tree.target); 1936 reloadStackBeforeSwitchExpr(); 1937 falseJumps = code.branch(goto_); 1938 1939 if (switchExpressionTrueChain == null) { 1940 switchExpressionTrueChain = trueJumps; 1941 } else { 1942 switchExpressionTrueChain = 1943 Code.mergeChains(switchExpressionTrueChain, trueJumps); 1944 } 1945 if (switchExpressionFalseChain == null) { 1946 switchExpressionFalseChain = falseJumps; 1947 } else { 1948 switchExpressionFalseChain = 1949 Code.mergeChains(switchExpressionFalseChain, falseJumps); 1950 } 1951 } else { 1952 genExpr(tree.value, pt).load(); 1953 if (switchResult != null) 1954 switchResult.store(); 1955 1956 targetEnv = unwindBreak(tree.target); 1957 1958 if (code.isAlive()) { 1959 reloadStackBeforeSwitchExpr(); 1960 if (switchResult != null) 1961 switchResult.load(); 1962 1963 code.state.forceStackTop(tree.target.type); 1964 targetEnv.info.addExit(code.branch(goto_)); 1965 code.markDead(); 1966 } 1967 } 1968 endFinalizerGaps(env, targetEnv); 1969 } 1970 //where: 1971 /** As side-effect, might mark code as dead disabling any further emission. 1972 */ 1973 private Env<GenContext> unwindBreak(JCTree target) { 1974 int tmpPos = code.pendingStatPos; 1975 Env<GenContext> targetEnv = unwind(target, env); 1976 code.pendingStatPos = tmpPos; 1977 return targetEnv; 1978 } 1979 1980 private void reloadStackBeforeSwitchExpr() { 1981 for (LocalItem li : stackBeforeSwitchExpression) 1982 li.load(); 1983 } 1984 1985 public void visitContinue(JCContinue tree) { 1986 int tmpPos = code.pendingStatPos; 1987 Env<GenContext> targetEnv = unwind(tree.target, env); 1988 code.pendingStatPos = tmpPos; 1989 Assert.check(code.isStatementStart()); 1990 targetEnv.info.addCont(code.branch(goto_)); 1991 endFinalizerGaps(env, targetEnv); 1992 } 1993 1994 public void visitReturn(JCReturn tree) { 1995 int limit = code.nextreg; 1996 final Env<GenContext> targetEnv; 1997 1998 /* Save and then restore the location of the return in case a finally 1999 * is expanded (with unwind()) in the middle of our bytecodes. 2000 */ 2001 int tmpPos = code.pendingStatPos; 2002 if (tree.expr != null) { 2003 Assert.check(code.isStatementStart()); 2004 Item r = genExpr(tree.expr, pt).load(); 2005 if (hasFinally(env.enclMethod, env)) { 2006 r = makeTemp(pt); 2007 r.store(); 2008 } 2009 targetEnv = unwind(env.enclMethod, env); 2010 code.pendingStatPos = tmpPos; 2011 r.load(); 2012 code.emitop0(ireturn + Code.truncate(Code.typecode(pt))); 2013 } else { 2014 targetEnv = unwind(env.enclMethod, env); 2015 code.pendingStatPos = tmpPos; 2016 code.emitop0(return_); 2017 } 2018 endFinalizerGaps(env, targetEnv); 2019 code.endScopes(limit); 2020 } 2021 2022 public void visitThrow(JCThrow tree) { 2023 Assert.check(code.isStatementStart()); 2024 genExpr(tree.expr, tree.expr.type).load(); 2025 code.emitop0(athrow); 2026 Assert.check(code.isStatementStart()); 2027 } 2028 2029 /* ************************************************************************ 2030 * Visitor methods for expressions 2031 *************************************************************************/ 2032 2033 public void visitApply(JCMethodInvocation tree) { 2034 setTypeAnnotationPositions(tree.pos); 2035 // Generate code for method. 2036 Item m = genExpr(tree.meth, methodType); 2037 // Generate code for all arguments, where the expected types are 2038 // the parameters of the method's external type (that is, any implicit 2039 // outer instance of a super(...) call appears as first parameter). 2040 MethodSymbol msym = (MethodSymbol)TreeInfo.symbol(tree.meth); 2041 genArgs(tree.args, 2042 msym.externalType(types).getParameterTypes()); 2043 if (!msym.isDynamic()) { 2044 code.statBegin(tree.pos); 2045 } 2046 if (patternMatchingCatchConfiguration.invocations().contains(tree)) { 2047 int start = code.curCP(); 2048 result = m.invoke(); 2049 patternMatchingCatchConfiguration.ranges().add(new int[] {start, code.curCP()}); 2050 } else { 2051 if (msym.isConstructor() && TreeInfo.isConstructorCall(tree)) { 2052 //if this is a this(...) or super(...) call, there is a pending 2053 //"uninitialized this" before this call. One catch handler cannot 2054 //handle exceptions that may come from places with "uninitialized this" 2055 //and (initialized) this, hence generate one set of handlers here 2056 //for the "uninitialized this" case, and another set of handlers 2057 //will be generated at the end of the method for the initialized this, 2058 //if needed: 2059 generatePatternMatchingCatch(env); 2060 result = m.invoke(); 2061 patternMatchingCatchConfiguration = 2062 patternMatchingCatchConfiguration.restart(code.state.dup()); 2063 } else { 2064 result = m.invoke(); 2065 } 2066 } 2067 } 2068 2069 public void visitConditional(JCConditional tree) { 2070 Chain thenExit = null; 2071 code.statBegin(tree.cond.pos); 2072 CondItem c = genCond(tree.cond, CRT_FLOW_CONTROLLER); 2073 Chain elseChain = c.jumpFalse(); 2074 if (!c.isFalse()) { 2075 code.resolve(c.trueJumps); 2076 int startpc = genCrt ? code.curCP() : 0; 2077 code.statBegin(tree.truepart.pos); 2078 genExpr(tree.truepart, pt).load(); 2079 code.state.forceStackTop(tree.type); 2080 if (genCrt) code.crt.put(tree.truepart, CRT_FLOW_TARGET, 2081 startpc, code.curCP()); 2082 thenExit = code.branch(goto_); 2083 } 2084 if (elseChain != null) { 2085 code.resolve(elseChain); 2086 int startpc = genCrt ? code.curCP() : 0; 2087 code.statBegin(tree.falsepart.pos); 2088 genExpr(tree.falsepart, pt).load(); 2089 code.state.forceStackTop(tree.type); 2090 if (genCrt) code.crt.put(tree.falsepart, CRT_FLOW_TARGET, 2091 startpc, code.curCP()); 2092 } 2093 code.resolve(thenExit); 2094 result = items.makeStackItem(pt); 2095 } 2096 2097 private void setTypeAnnotationPositions(int treePos) { 2098 MethodSymbol meth = code.meth; 2099 boolean initOrClinit = code.meth.getKind() == javax.lang.model.element.ElementKind.CONSTRUCTOR 2100 || code.meth.getKind() == javax.lang.model.element.ElementKind.STATIC_INIT; 2101 2102 for (Attribute.TypeCompound ta : meth.getRawTypeAttributes()) { 2103 if (ta.hasUnknownPosition()) 2104 ta.tryFixPosition(); 2105 2106 if (ta.position.matchesPos(treePos)) 2107 ta.position.updatePosOffset(code.cp); 2108 } 2109 2110 if (!initOrClinit) 2111 return; 2112 2113 for (Attribute.TypeCompound ta : meth.owner.getRawTypeAttributes()) { 2114 if (ta.hasUnknownPosition()) 2115 ta.tryFixPosition(); 2116 2117 if (ta.position.matchesPos(treePos)) 2118 ta.position.updatePosOffset(code.cp); 2119 } 2120 2121 ClassSymbol clazz = meth.enclClass(); 2122 for (Symbol s : new com.sun.tools.javac.model.FilteredMemberList(clazz.members())) { 2123 if (!s.getKind().isField()) 2124 continue; 2125 2126 for (Attribute.TypeCompound ta : s.getRawTypeAttributes()) { 2127 if (ta.hasUnknownPosition()) 2128 ta.tryFixPosition(); 2129 2130 if (ta.position.matchesPos(treePos)) 2131 ta.position.updatePosOffset(code.cp); 2132 } 2133 } 2134 } 2135 2136 public void visitNewClass(JCNewClass tree) { 2137 // Enclosing instances or anonymous classes should have been eliminated 2138 // by now. 2139 Assert.check(tree.encl == null && tree.def == null); 2140 setTypeAnnotationPositions(tree.pos); 2141 2142 code.emitop2(new_, checkDimension(tree.pos(), tree.type), PoolWriter::putClass); 2143 code.emitop0(dup); 2144 2145 // Generate code for all arguments, where the expected types are 2146 // the parameters of the constructor's external type (that is, 2147 // any implicit outer instance appears as first parameter). 2148 genArgs(tree.args, tree.constructor.externalType(types).getParameterTypes()); 2149 2150 items.makeMemberItem(tree.constructor, true).invoke(); 2151 result = items.makeStackItem(tree.type); 2152 } 2153 2154 public void visitNewArray(JCNewArray tree) { 2155 setTypeAnnotationPositions(tree.pos); 2156 2157 if (tree.elems != null) { 2158 Type elemtype = types.elemtype(tree.type); 2159 loadIntConst(tree.elems.length()); 2160 Item arr = makeNewArray(tree.pos(), tree.type, 1); 2161 int i = 0; 2162 for (List<JCExpression> l = tree.elems; l.nonEmpty(); l = l.tail) { 2163 arr.duplicate(); 2164 loadIntConst(i); 2165 i++; 2166 genExpr(l.head, elemtype).load(); 2167 items.makeIndexedItem(elemtype).store(); 2168 } 2169 result = arr; 2170 } else { 2171 for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) { 2172 genExpr(l.head, syms.intType).load(); 2173 } 2174 result = makeNewArray(tree.pos(), tree.type, tree.dims.length()); 2175 } 2176 } 2177 //where 2178 /** Generate code to create an array with given element type and number 2179 * of dimensions. 2180 */ 2181 Item makeNewArray(DiagnosticPosition pos, Type type, int ndims) { 2182 Type elemtype = types.elemtype(type); 2183 if (types.dimensions(type) > ClassFile.MAX_DIMENSIONS) { 2184 log.error(pos, Errors.LimitDimensions); 2185 nerrs++; 2186 } 2187 int elemcode = Code.arraycode(elemtype); 2188 if (elemcode == 0 || (elemcode == 1 && ndims == 1)) { 2189 code.emitAnewarray(makeRef(pos, elemtype), type); 2190 } else if (elemcode == 1) { 2191 code.emitMultianewarray(ndims, makeRef(pos, type), type); 2192 } else { 2193 code.emitNewarray(elemcode, type); 2194 } 2195 return items.makeStackItem(type); 2196 } 2197 2198 public void visitParens(JCParens tree) { 2199 result = genExpr(tree.expr, tree.expr.type); 2200 } 2201 2202 public void visitAssign(JCAssign tree) { 2203 Item l = genExpr(tree.lhs, tree.lhs.type); 2204 genExpr(tree.rhs, tree.lhs.type).load(); 2205 Set<VarSymbol> tmpUnsetSymbols = unsetFieldsInfo.getUnsetFields(env.enclClass.sym, tree); 2206 code.currentUnsetFields = tmpUnsetSymbols != null ? tmpUnsetSymbols : code.currentUnsetFields; 2207 if (tree.rhs.type.hasTag(BOT)) { 2208 /* This is just a case of widening reference conversion that per 5.1.5 simply calls 2209 for "regarding a reference as having some other type in a manner that can be proved 2210 correct at compile time." 2211 */ 2212 code.state.forceStackTop(tree.lhs.type); 2213 } 2214 result = items.makeAssignItem(l); 2215 } 2216 2217 public void visitAssignop(JCAssignOp tree) { 2218 OperatorSymbol operator = tree.operator; 2219 Item l; 2220 if (operator.opcode == string_add) { 2221 l = concat.makeConcat(tree); 2222 } else { 2223 // Generate code for first expression 2224 l = genExpr(tree.lhs, tree.lhs.type); 2225 2226 // If we have an increment of -32768 to +32767 of a local 2227 // int variable we can use an incr instruction instead of 2228 // proceeding further. 2229 if ((tree.hasTag(PLUS_ASG) || tree.hasTag(MINUS_ASG)) && 2230 l instanceof LocalItem localItem && 2231 tree.lhs.type.getTag().isSubRangeOf(INT) && 2232 tree.rhs.type.getTag().isSubRangeOf(INT) && 2233 tree.rhs.type.constValue() != null) { 2234 int ival = ((Number) tree.rhs.type.constValue()).intValue(); 2235 if (tree.hasTag(MINUS_ASG)) ival = -ival; 2236 localItem.incr(ival); 2237 result = l; 2238 return; 2239 } 2240 // Otherwise, duplicate expression, load one copy 2241 // and complete binary operation. 2242 l.duplicate(); 2243 l.coerce(operator.type.getParameterTypes().head).load(); 2244 completeBinop(tree.lhs, tree.rhs, operator).coerce(tree.lhs.type); 2245 } 2246 result = items.makeAssignItem(l); 2247 } 2248 2249 public void visitUnary(JCUnary tree) { 2250 OperatorSymbol operator = tree.operator; 2251 if (tree.hasTag(NOT)) { 2252 CondItem od = genCond(tree.arg, false); 2253 result = od.negate(); 2254 } else { 2255 Item od = genExpr(tree.arg, operator.type.getParameterTypes().head); 2256 switch (tree.getTag()) { 2257 case POS: 2258 result = od.load(); 2259 break; 2260 case NEG: 2261 result = od.load(); 2262 code.emitop0(operator.opcode); 2263 break; 2264 case COMPL: 2265 result = od.load(); 2266 emitMinusOne(od.typecode); 2267 code.emitop0(operator.opcode); 2268 break; 2269 case PREINC: case PREDEC: 2270 od.duplicate(); 2271 if (od instanceof LocalItem localItem && 2272 (operator.opcode == iadd || operator.opcode == isub)) { 2273 localItem.incr(tree.hasTag(PREINC) ? 1 : -1); 2274 result = od; 2275 } else { 2276 od.load(); 2277 code.emitop0(one(od.typecode)); 2278 code.emitop0(operator.opcode); 2279 // Perform narrowing primitive conversion if byte, 2280 // char, or short. Fix for 4304655. 2281 if (od.typecode != INTcode && 2282 Code.truncate(od.typecode) == INTcode) 2283 code.emitop0(int2byte + od.typecode - BYTEcode); 2284 result = items.makeAssignItem(od); 2285 } 2286 break; 2287 case POSTINC: case POSTDEC: 2288 od.duplicate(); 2289 if (od instanceof LocalItem localItem && 2290 (operator.opcode == iadd || operator.opcode == isub)) { 2291 Item res = od.load(); 2292 localItem.incr(tree.hasTag(POSTINC) ? 1 : -1); 2293 result = res; 2294 } else { 2295 Item res = od.load(); 2296 od.stash(od.typecode); 2297 code.emitop0(one(od.typecode)); 2298 code.emitop0(operator.opcode); 2299 // Perform narrowing primitive conversion if byte, 2300 // char, or short. Fix for 4304655. 2301 if (od.typecode != INTcode && 2302 Code.truncate(od.typecode) == INTcode) 2303 code.emitop0(int2byte + od.typecode - BYTEcode); 2304 od.store(); 2305 result = res; 2306 } 2307 break; 2308 case NULLCHK: 2309 result = od.load(); 2310 code.emitop0(dup); 2311 genNullCheck(tree); 2312 break; 2313 default: 2314 Assert.error(); 2315 } 2316 } 2317 } 2318 2319 /** Generate a null check from the object value at stack top. */ 2320 private void genNullCheck(JCTree tree) { 2321 code.statBegin(tree.pos); 2322 callMethod(tree.pos(), syms.objectsType, names.requireNonNull, 2323 List.of(syms.objectType), true); 2324 code.emitop0(pop); 2325 } 2326 2327 public void visitBinary(JCBinary tree) { 2328 OperatorSymbol operator = tree.operator; 2329 if (operator.opcode == string_add) { 2330 result = concat.makeConcat(tree); 2331 } else if (tree.hasTag(AND)) { 2332 CondItem lcond = genCond(tree.lhs, CRT_FLOW_CONTROLLER); 2333 if (!lcond.isFalse()) { 2334 Chain falseJumps = lcond.jumpFalse(); 2335 code.resolve(lcond.trueJumps); 2336 CondItem rcond = genCond(tree.rhs, CRT_FLOW_TARGET); 2337 result = items. 2338 makeCondItem(rcond.opcode, 2339 rcond.trueJumps, 2340 Code.mergeChains(falseJumps, 2341 rcond.falseJumps)); 2342 } else { 2343 result = lcond; 2344 } 2345 } else if (tree.hasTag(OR)) { 2346 CondItem lcond = genCond(tree.lhs, CRT_FLOW_CONTROLLER); 2347 if (!lcond.isTrue()) { 2348 Chain trueJumps = lcond.jumpTrue(); 2349 code.resolve(lcond.falseJumps); 2350 CondItem rcond = genCond(tree.rhs, CRT_FLOW_TARGET); 2351 result = items. 2352 makeCondItem(rcond.opcode, 2353 Code.mergeChains(trueJumps, rcond.trueJumps), 2354 rcond.falseJumps); 2355 } else { 2356 result = lcond; 2357 } 2358 } else { 2359 Item od = genExpr(tree.lhs, operator.type.getParameterTypes().head); 2360 od.load(); 2361 result = completeBinop(tree.lhs, tree.rhs, operator); 2362 } 2363 } 2364 2365 2366 /** Complete generating code for operation, with left operand 2367 * already on stack. 2368 * @param lhs The tree representing the left operand. 2369 * @param rhs The tree representing the right operand. 2370 * @param operator The operator symbol. 2371 */ 2372 Item completeBinop(JCTree lhs, JCTree rhs, OperatorSymbol operator) { 2373 MethodType optype = (MethodType)operator.type; 2374 int opcode = operator.opcode; 2375 if (opcode >= if_icmpeq && opcode <= if_icmple && 2376 rhs.type.constValue() instanceof Number number && 2377 number.intValue() == 0) { 2378 opcode = opcode + (ifeq - if_icmpeq); 2379 } else if (opcode >= if_acmpeq && opcode <= if_acmpne && 2380 TreeInfo.isNull(rhs)) { 2381 opcode = opcode + (if_acmp_null - if_acmpeq); 2382 } else { 2383 // The expected type of the right operand is 2384 // the second parameter type of the operator, except for 2385 // shifts with long shiftcount, where we convert the opcode 2386 // to a short shift and the expected type to int. 2387 Type rtype = operator.erasure(types).getParameterTypes().tail.head; 2388 if (opcode >= ishll && opcode <= lushrl) { 2389 opcode = opcode + (ishl - ishll); 2390 rtype = syms.intType; 2391 } 2392 // Generate code for right operand and load. 2393 genExpr(rhs, rtype).load(); 2394 // If there are two consecutive opcode instructions, 2395 // emit the first now. 2396 if (opcode >= (1 << preShift)) { 2397 code.emitop0(opcode >> preShift); 2398 opcode = opcode & 0xFF; 2399 } 2400 } 2401 if (opcode >= ifeq && opcode <= if_acmpne || 2402 opcode == if_acmp_null || opcode == if_acmp_nonnull) { 2403 return items.makeCondItem(opcode); 2404 } else { 2405 code.emitop0(opcode); 2406 return items.makeStackItem(optype.restype); 2407 } 2408 } 2409 2410 public void visitTypeCast(JCTypeCast tree) { 2411 result = genExpr(tree.expr, tree.clazz.type).load(); 2412 setTypeAnnotationPositions(tree.pos); 2413 // Additional code is only needed if we cast to a reference type 2414 // which is not statically a supertype of the expression's type. 2415 // For basic types, the coerce(...) in genExpr(...) will do 2416 // the conversion. 2417 if (!tree.clazz.type.isPrimitive() && 2418 !types.isSameType(tree.expr.type, tree.clazz.type) && 2419 types.asSuper(tree.expr.type, tree.clazz.type.tsym) == null) { 2420 code.emitop2(checkcast, checkDimension(tree.pos(), tree.clazz.type), PoolWriter::putClass); 2421 } 2422 } 2423 2424 public void visitWildcard(JCWildcard tree) { 2425 throw new AssertionError(this.getClass().getName()); 2426 } 2427 2428 public void visitTypeTest(JCInstanceOf tree) { 2429 genExpr(tree.expr, tree.expr.type).load(); 2430 setTypeAnnotationPositions(tree.pos); 2431 code.emitop2(instanceof_, makeRef(tree.pos(), tree.pattern.type)); 2432 result = items.makeStackItem(syms.booleanType); 2433 } 2434 2435 public void visitIndexed(JCArrayAccess tree) { 2436 genExpr(tree.indexed, tree.indexed.type).load(); 2437 genExpr(tree.index, syms.intType).load(); 2438 result = items.makeIndexedItem(tree.type); 2439 } 2440 2441 public void visitIdent(JCIdent tree) { 2442 Symbol sym = tree.sym; 2443 if (tree.name == names._this || tree.name == names._super) { 2444 Item res = tree.name == names._this 2445 ? items.makeThisItem() 2446 : items.makeSuperItem(); 2447 if (sym.kind == MTH) { 2448 // Generate code to address the constructor. 2449 res.load(); 2450 res = items.makeMemberItem(sym, true); 2451 } 2452 result = res; 2453 } else if (isInvokeDynamic(sym) || isConstantDynamic(sym)) { 2454 if (isConstantDynamic(sym)) { 2455 setTypeAnnotationPositions(tree.pos); 2456 } 2457 result = items.makeDynamicItem(sym); 2458 } else if (sym.kind == VAR && (sym.owner.kind == MTH || sym.owner.kind == VAR)) { 2459 result = items.makeLocalItem((VarSymbol)sym); 2460 } else if ((sym.flags() & STATIC) != 0) { 2461 if (!isAccessSuper(env.enclMethod)) 2462 sym = binaryQualifier(sym, env.enclClass.type); 2463 result = items.makeStaticItem(sym); 2464 } else { 2465 items.makeThisItem().load(); 2466 sym = binaryQualifier(sym, env.enclClass.type); 2467 result = items.makeMemberItem(sym, nonVirtualForPrivateAccess(sym)); 2468 } 2469 } 2470 2471 //where 2472 private boolean nonVirtualForPrivateAccess(Symbol sym) { 2473 boolean useVirtual = target.hasVirtualPrivateInvoke() && 2474 !disableVirtualizedPrivateInvoke; 2475 return !useVirtual && ((sym.flags() & PRIVATE) != 0); 2476 } 2477 2478 public void visitSelect(JCFieldAccess tree) { 2479 Symbol sym = tree.sym; 2480 2481 if (tree.name == names._class) { 2482 code.emitLdc((LoadableConstant)checkDimension(tree.pos(), tree.selected.type)); 2483 result = items.makeStackItem(pt); 2484 return; 2485 } 2486 2487 Symbol ssym = TreeInfo.symbol(tree.selected); 2488 2489 // Are we selecting via super? 2490 boolean selectSuper = 2491 ssym != null && (ssym.kind == TYP || ssym.name == names._super); 2492 2493 // Are we accessing a member of the superclass in an access method 2494 // resulting from a qualified super? 2495 boolean accessSuper = isAccessSuper(env.enclMethod); 2496 2497 Item base = (selectSuper) 2498 ? items.makeSuperItem() 2499 : genExpr(tree.selected, tree.selected.type); 2500 2501 if (sym.kind == VAR && ((VarSymbol) sym).getConstValue() != null) { 2502 // We are seeing a variable that is constant but its selecting 2503 // expression is not. 2504 if ((sym.flags() & STATIC) != 0) { 2505 if (!selectSuper && (ssym == null || ssym.kind != TYP)) 2506 base = base.load(); 2507 base.drop(); 2508 } else { 2509 base.load(); 2510 genNullCheck(tree.selected); 2511 } 2512 result = items. 2513 makeImmediateItem(sym.type, ((VarSymbol) sym).getConstValue()); 2514 } else { 2515 if (isInvokeDynamic(sym)) { 2516 result = items.makeDynamicItem(sym); 2517 return; 2518 } else { 2519 sym = binaryQualifier(sym, tree.selected.type); 2520 } 2521 if ((sym.flags() & STATIC) != 0) { 2522 if (!selectSuper && (ssym == null || ssym.kind != TYP)) 2523 base = base.load(); 2524 base.drop(); 2525 result = items.makeStaticItem(sym); 2526 } else { 2527 base.load(); 2528 if (sym == syms.lengthVar) { 2529 code.emitop0(arraylength); 2530 result = items.makeStackItem(syms.intType); 2531 } else { 2532 result = items. 2533 makeMemberItem(sym, 2534 nonVirtualForPrivateAccess(sym) || 2535 selectSuper || accessSuper); 2536 } 2537 } 2538 } 2539 } 2540 2541 public boolean isInvokeDynamic(Symbol sym) { 2542 return sym.kind == MTH && ((MethodSymbol)sym).isDynamic(); 2543 } 2544 2545 public void visitLiteral(JCLiteral tree) { 2546 if (tree.type.hasTag(BOT)) { 2547 code.emitop0(aconst_null); 2548 result = items.makeStackItem(tree.type); 2549 } 2550 else 2551 result = items.makeImmediateItem(tree.type, tree.value); 2552 } 2553 2554 public void visitLetExpr(LetExpr tree) { 2555 code.resolvePending(); 2556 2557 int limit = code.nextreg; 2558 int prevLetExprStart = code.setLetExprStackPos(code.state.stacksize); 2559 try { 2560 genStats(tree.defs, env); 2561 } finally { 2562 code.setLetExprStackPos(prevLetExprStart); 2563 } 2564 result = genExpr(tree.expr, tree.expr.type).load(); 2565 code.endScopes(limit); 2566 } 2567 2568 private void generateReferencesToPrunedTree(ClassSymbol classSymbol) { 2569 List<JCTree> prunedInfo = lower.prunedTree.get(classSymbol); 2570 if (prunedInfo != null) { 2571 for (JCTree prunedTree: prunedInfo) { 2572 prunedTree.accept(classReferenceVisitor); 2573 } 2574 } 2575 } 2576 2577 /* ************************************************************************ 2578 * main method 2579 *************************************************************************/ 2580 2581 /** Generate code for a class definition. 2582 * @param env The attribution environment that belongs to the 2583 * outermost class containing this class definition. 2584 * We need this for resolving some additional symbols. 2585 * @param cdef The tree representing the class definition. 2586 * @return True if code is generated with no errors. 2587 */ 2588 public boolean genClass(Env<AttrContext> env, JCClassDecl cdef) { 2589 try { 2590 attrEnv = env; 2591 ClassSymbol c = cdef.sym; 2592 this.toplevel = env.toplevel; 2593 this.endPosTable = toplevel.endPositions; 2594 /* method normalizeDefs() can add references to external classes into the constant pool 2595 */ 2596 cdef.defs = normalizeDefs(cdef.defs, c); 2597 generateReferencesToPrunedTree(c); 2598 Env<GenContext> localEnv = new Env<>(cdef, new GenContext()); 2599 localEnv.toplevel = env.toplevel; 2600 localEnv.enclClass = cdef; 2601 2602 for (List<JCTree> l = cdef.defs; l.nonEmpty(); l = l.tail) { 2603 genDef(l.head, localEnv); 2604 } 2605 if (poolWriter.size() > PoolWriter.MAX_ENTRIES) { 2606 log.error(cdef.pos(), Errors.LimitPool); 2607 nerrs++; 2608 } 2609 if (nerrs != 0) { 2610 // if errors, discard code 2611 for (List<JCTree> l = cdef.defs; l.nonEmpty(); l = l.tail) { 2612 if (l.head.hasTag(METHODDEF)) 2613 ((JCMethodDecl) l.head).sym.code = null; 2614 } 2615 } 2616 cdef.defs = List.nil(); // discard trees 2617 return nerrs == 0; 2618 } finally { 2619 // note: this method does NOT support recursion. 2620 attrEnv = null; 2621 this.env = null; 2622 toplevel = null; 2623 endPosTable = null; 2624 nerrs = 0; 2625 qualifiedSymbolCache.clear(); 2626 } 2627 } 2628 2629 /* ************************************************************************ 2630 * Auxiliary classes 2631 *************************************************************************/ 2632 2633 /** An abstract class for finalizer generation. 2634 */ 2635 abstract class GenFinalizer { 2636 /** Generate code to clean up when unwinding. */ 2637 abstract void gen(); 2638 2639 /** Generate code to clean up at last. */ 2640 abstract void genLast(); 2641 2642 /** Does this finalizer have some nontrivial cleanup to perform? */ 2643 boolean hasFinalizer() { return true; } 2644 2645 /** Should be invoked after the try's body has been visited. */ 2646 void afterBody() {} 2647 } 2648 2649 /** code generation contexts, 2650 * to be used as type parameter for environments. 2651 */ 2652 static class GenContext { 2653 2654 /** A chain for all unresolved jumps that exit the current environment. 2655 */ 2656 Chain exit = null; 2657 2658 /** A chain for all unresolved jumps that continue in the 2659 * current environment. 2660 */ 2661 Chain cont = null; 2662 2663 /** A closure that generates the finalizer of the current environment. 2664 * Only set for Synchronized and Try contexts. 2665 */ 2666 GenFinalizer finalize = null; 2667 2668 /** Is this a switch statement? If so, allocate registers 2669 * even when the variable declaration is unreachable. 2670 */ 2671 boolean isSwitch = false; 2672 2673 /** A list buffer containing all gaps in the finalizer range, 2674 * where a catch all exception should not apply. 2675 */ 2676 ListBuffer<Integer> gaps = null; 2677 2678 /** Add given chain to exit chain. 2679 */ 2680 void addExit(Chain c) { 2681 exit = Code.mergeChains(c, exit); 2682 } 2683 2684 /** Add given chain to cont chain. 2685 */ 2686 void addCont(Chain c) { 2687 cont = Code.mergeChains(c, cont); 2688 } 2689 } 2690 2691 record PatternMatchingCatchConfiguration(Set<JCMethodInvocation> invocations, 2692 ListBuffer<int[]> ranges, 2693 JCCatch handler, 2694 State startState) { 2695 public PatternMatchingCatchConfiguration restart(State newState) { 2696 return new PatternMatchingCatchConfiguration(invocations(), 2697 new ListBuffer<int[]>(), 2698 handler(), 2699 newState); 2700 } 2701 } 2702 }