1 /*
2 * Copyright (c) 1999, 2022, 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.comp;
27
28 import java.util.*;
29 import java.util.stream.Collectors;
30
31 import com.sun.source.tree.LambdaExpressionTree.BodyKind;
32 import com.sun.tools.javac.code.*;
33 import com.sun.tools.javac.code.Kinds.KindSelector;
34 import com.sun.tools.javac.code.Scope.WriteableScope;
35 import com.sun.tools.javac.jvm.*;
36 import com.sun.tools.javac.jvm.PoolConstant.LoadableConstant;
37 import com.sun.tools.javac.main.Option.PkgInfo;
38 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
39 import com.sun.tools.javac.resources.CompilerProperties.Notes;
40 import com.sun.tools.javac.tree.*;
41 import com.sun.tools.javac.util.*;
42 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
43 import com.sun.tools.javac.util.List;
44
45 import com.sun.tools.javac.code.Symbol.*;
46 import com.sun.tools.javac.code.Symbol.OperatorSymbol.AccessCode;
47 import com.sun.tools.javac.resources.CompilerProperties.Errors;
48 import com.sun.tools.javac.tree.JCTree.*;
49 import com.sun.tools.javac.code.Type.*;
50
51 import com.sun.tools.javac.jvm.Target;
52 import com.sun.tools.javac.tree.EndPosTable;
53
54 import static com.sun.tools.javac.code.Flags.*;
55 import static com.sun.tools.javac.code.Flags.BLOCK;
56 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
57 import static com.sun.tools.javac.code.TypeTag.*;
58 import static com.sun.tools.javac.code.Kinds.Kind.*;
59 import com.sun.tools.javac.code.Source.Feature;
60 import static com.sun.tools.javac.jvm.ByteCodes.*;
61 import com.sun.tools.javac.tree.JCTree.JCBreak;
62 import com.sun.tools.javac.tree.JCTree.JCCase;
63 import com.sun.tools.javac.tree.JCTree.JCExpression;
64 import com.sun.tools.javac.tree.JCTree.JCExpressionStatement;
65
66 import static com.sun.tools.javac.tree.JCTree.JCOperatorExpression.OperandPos.LEFT;
67 import com.sun.tools.javac.tree.JCTree.JCSwitchExpression;
68
69 import static com.sun.tools.javac.tree.JCTree.Tag.*;
70
71 /** This pass translates away some syntactic sugar: inner classes,
72 * class literals, assertions, foreach loops, etc.
73 *
74 * <p><b>This is NOT part of any supported API.
75 * If you write code that depends on this, you do so at your own risk.
76 * This code and its internal interfaces are subject to change or
77 * deletion without notice.</b>
78 */
79 public class Lower extends TreeTranslator {
80 protected static final Context.Key<Lower> lowerKey = new Context.Key<>();
81
82 public static Lower instance(Context context) {
83 Lower instance = context.get(lowerKey);
84 if (instance == null)
85 instance = new Lower(context);
86 return instance;
87 }
88
89 private final Names names;
90 private final Log log;
91 private final Symtab syms;
92 private final Resolve rs;
93 private final Operators operators;
94 private final Check chk;
95 private final Attr attr;
96 private TreeMaker make;
97 private DiagnosticPosition make_pos;
98 private final ConstFold cfolder;
99 private final Target target;
100 private final TypeEnvs typeEnvs;
101 private final Name dollarAssertionsDisabled;
102 private final Types types;
103 private final TransTypes transTypes;
104 private final boolean debugLower;
105 private final boolean disableProtectedAccessors; // experimental
106 private final PkgInfo pkginfoOpt;
107 private final boolean optimizeOuterThis;
108 private final boolean useMatchException;
109 private final HashMap<TypePairs, String> typePairToName;
110 private final boolean allowValueClasses;
111 private int variableIndex = 0;
112
113 @SuppressWarnings("this-escape")
114 protected Lower(Context context) {
115 context.put(lowerKey, this);
116 names = Names.instance(context);
117 log = Log.instance(context);
118 syms = Symtab.instance(context);
119 rs = Resolve.instance(context);
120 operators = Operators.instance(context);
121 chk = Check.instance(context);
122 attr = Attr.instance(context);
123 make = TreeMaker.instance(context);
124 cfolder = ConstFold.instance(context);
125 target = Target.instance(context);
126 typeEnvs = TypeEnvs.instance(context);
127 dollarAssertionsDisabled = names.
128 fromString(target.syntheticNameChar() + "assertionsDisabled");
129
130 types = Types.instance(context);
131 transTypes = TransTypes.instance(context);
132 Options options = Options.instance(context);
133 debugLower = options.isSet("debuglower");
134 pkginfoOpt = PkgInfo.get(options);
135 optimizeOuterThis =
136 target.optimizeOuterThis() ||
137 options.getBoolean("optimizeOuterThis", false);
138 disableProtectedAccessors = options.isSet("disableProtectedAccessors");
139 Source source = Source.instance(context);
140 Preview preview = Preview.instance(context);
141 useMatchException = Feature.PATTERN_SWITCH.allowedInSource(source) &&
142 (preview.isEnabled() || !preview.isPreview(Feature.PATTERN_SWITCH));
143 typePairToName = TypePairs.initialize(syms);
144 this.allowValueClasses = (!preview.isPreview(Feature.VALUE_CLASSES) || preview.isEnabled()) &&
145 Feature.VALUE_CLASSES.allowedInSource(source);
146 }
147
148 /** The currently enclosing class.
149 */
150 ClassSymbol currentClass;
151
152 /** A queue of all translated classes.
153 */
154 ListBuffer<JCTree> translated;
155
156 /** Environment for symbol lookup, set by translateTopLevelClass.
157 */
158 Env<AttrContext> attrEnv;
159
160 /** A hash table mapping syntax trees to their ending source positions.
161 */
162 EndPosTable endPosTable;
163
164 /* ************************************************************************
165 * Global mappings
166 *************************************************************************/
167
168 /** A hash table mapping local classes to their definitions.
169 */
170 Map<ClassSymbol, JCClassDecl> classdefs;
171
172 /** A hash table mapping local classes to a list of pruned trees.
173 */
174 public Map<ClassSymbol, List<JCTree>> prunedTree = new WeakHashMap<>();
175
176 /** A hash table mapping virtual accessed symbols in outer subclasses
177 * to the actually referred symbol in superclasses.
178 */
179 Map<Symbol,Symbol> actualSymbols;
180
181 /**
182 * The current expected return type.
183 */
184 Type currentRestype;
185
186 /** The current method definition.
187 */
188 JCMethodDecl currentMethodDef;
189
190 /** The current method symbol.
191 */
192 MethodSymbol currentMethodSym;
193
194 /** The currently enclosing outermost class definition.
195 */
196 JCClassDecl outermostClassDef;
197
198 /** The currently enclosing outermost member definition.
199 */
200 JCTree outermostMemberDef;
201
202 /** A hash table mapping local classes to a set of outer this fields
203 */
204 public Map<ClassSymbol, Set<JCExpression>> initializerOuterThis = new WeakHashMap<>();
205
206 /** A navigator class for assembling a mapping from local class symbols
207 * to class definition trees.
208 * There is only one case; all other cases simply traverse down the tree.
209 */
210 class ClassMap extends TreeScanner {
211
212 /** All encountered class defs are entered into classdefs table.
213 */
214 public void visitClassDef(JCClassDecl tree) {
215 classdefs.put(tree.sym, tree);
216 super.visitClassDef(tree);
217 }
218 }
219 ClassMap classMap = new ClassMap();
220
221 /** Map a class symbol to its definition.
222 * @param c The class symbol of which we want to determine the definition.
223 */
224 JCClassDecl classDef(ClassSymbol c) {
225 // First lookup the class in the classdefs table.
226 JCClassDecl def = classdefs.get(c);
227 if (def == null && outermostMemberDef != null) {
228 // If this fails, traverse outermost member definition, entering all
229 // local classes into classdefs, and try again.
230 classMap.scan(outermostMemberDef);
231 def = classdefs.get(c);
232 }
233 if (def == null) {
234 // If this fails, traverse outermost class definition, entering all
235 // local classes into classdefs, and try again.
236 classMap.scan(outermostClassDef);
237 def = classdefs.get(c);
238 }
239 return def;
240 }
241
242 /**
243 * Get the enum constants for the given enum class symbol, if known.
244 * They will only be found if they are defined within the same top-level
245 * class as the class being compiled, so it's safe to assume that they
246 * can't change at runtime due to a recompilation.
247 */
248 List<Name> enumNamesFor(ClassSymbol c) {
249
250 // Find the class definition and verify it is an enum class
251 final JCClassDecl classDef = classDef(c);
252 if (classDef == null ||
253 (classDef.mods.flags & ENUM) == 0 ||
254 (types.supertype(currentClass.type).tsym.flags() & ENUM) != 0) {
255 return null;
256 }
257
258 // Gather the enum identifiers
259 ListBuffer<Name> idents = new ListBuffer<>();
260 for (List<JCTree> defs = classDef.defs; defs.nonEmpty(); defs=defs.tail) {
261 if (defs.head.hasTag(VARDEF) &&
262 (((JCVariableDecl) defs.head).mods.flags & ENUM) != 0) {
263 JCVariableDecl var = (JCVariableDecl)defs.head;
264 idents.append(var.name);
265 }
266 }
267 return idents.toList();
268 }
269
270 /** A hash table mapping class symbols to lists of free variables.
271 * accessed by them. Only free variables of the method immediately containing
272 * a class are associated with that class.
273 */
274 Map<ClassSymbol,List<VarSymbol>> freevarCache;
275
276 /** A navigator class for collecting the free variables accessed
277 * from a local class.
278 */
279 class FreeVarCollector extends CaptureScanner {
280
281 FreeVarCollector(JCTree ownerTree) {
282 super(ownerTree);
283 }
284
285 void addFreeVars(ClassSymbol c) {
286 List<VarSymbol> fvs = freevarCache.get(c);
287 if (fvs != null) {
288 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) {
289 addFreeVar(l.head);
290 }
291 }
292 }
293
294 /** If tree refers to a class instance creation expression
295 * add all free variables of the freshly created class.
296 */
297 public void visitNewClass(JCNewClass tree) {
298 ClassSymbol c = (ClassSymbol)tree.constructor.owner;
299 addFreeVars(c);
300 super.visitNewClass(tree);
301 }
302
303 /** If tree refers to a superclass constructor call,
304 * add all free variables of the superclass.
305 */
306 public void visitApply(JCMethodInvocation tree) {
307 if (TreeInfo.name(tree.meth) == names._super) {
308 addFreeVars((ClassSymbol) TreeInfo.symbol(tree.meth).owner);
309 }
310 super.visitApply(tree);
311 }
312 }
313
314 /** Return the variables accessed from within a local class, which
315 * are declared in the local class' owner.
316 * (in reverse order of first access).
317 */
318 List<VarSymbol> freevars(ClassSymbol c) {
319 List<VarSymbol> fvs = freevarCache.get(c);
320 if (fvs != null) {
321 return fvs;
322 }
323 FreeVarCollector collector = new FreeVarCollector(classDef(c));
324 fvs = collector.analyzeCaptures().reverse();
325 freevarCache.put(c, fvs);
326 return fvs;
327 }
328
329 Map<TypeSymbol,EnumMapping> enumSwitchMap = new LinkedHashMap<>();
330
331 EnumMapping mapForEnum(DiagnosticPosition pos, TypeSymbol enumClass) {
332
333 // If enum class is part of this compilation, just switch on ordinal value
334 if (enumClass.kind == TYP) {
335 final List<Name> idents = enumNamesFor((ClassSymbol)enumClass);
336 if (idents != null)
337 return new CompileTimeEnumMapping(idents);
338 }
339
340 // Map identifiers to ordinal values at runtime, and then switch on that
341 return enumSwitchMap.computeIfAbsent(enumClass, ec -> new RuntimeEnumMapping(pos, ec));
342 }
343
344 /** Generates a test value and corresponding cases for a switch on an enum type.
345 */
346 interface EnumMapping {
347
348 /** Given an expression for the enum value's ordinal, generate an expression for the switch statement.
349 */
350 JCExpression switchValue(JCExpression ordinalExpr);
351
352 /** Generate the switch statement case value corresponding to the given enum value.
353 */
354 JCLiteral caseValue(VarSymbol v);
355
356 default void translate() {
357 }
358 }
359
360 /** EnumMapping using compile-time constants. Only valid when compiling the enum class itself,
361 * because otherwise the ordinals we use could become obsolete if/when the enum class is recompiled.
362 */
363 class CompileTimeEnumMapping implements EnumMapping {
364
365 final List<Name> enumNames;
366
367 CompileTimeEnumMapping(List<Name> enumNames) {
368 Assert.check(enumNames != null);
369 this.enumNames = enumNames;
370 }
371
372 @Override
373 public JCExpression switchValue(JCExpression ordinalExpr) {
374 return ordinalExpr;
375 }
376
377 @Override
378 public JCLiteral caseValue(VarSymbol v) {
379 final int ordinal = enumNames.indexOf(v.name);
380 Assert.check(ordinal != -1);
381 return make.Literal(ordinal);
382 }
383 }
384
385 /** EnumMapping using run-time ordinal lookup.
386 *
387 * This builds a translation table to be used for enum switches.
388 *
389 * <p>For each enum that appears as the type of a switch
390 * expression, we maintain an EnumMapping to assist in the
391 * translation, as exemplified by the following example:
392 *
393 * <p>we translate
394 * <pre>
395 * switch(colorExpression) {
396 * case red: stmt1;
397 * case green: stmt2;
398 * }
399 * </pre>
400 * into
401 * <pre>
402 * switch(Outer$0.$EnumMap$Color[colorExpression.ordinal()]) {
403 * case 1: stmt1;
404 * case 2: stmt2
405 * }
406 * </pre>
407 * with the auxiliary table initialized as follows:
408 * <pre>
409 * class Outer$0 {
410 * synthetic final int[] $EnumMap$Color = new int[Color.values().length];
411 * static {
412 * try { $EnumMap$Color[red.ordinal()] = 1; } catch (NoSuchFieldError ex) {}
413 * try { $EnumMap$Color[green.ordinal()] = 2; } catch (NoSuchFieldError ex) {}
414 * }
415 * }
416 * </pre>
417 * class EnumMapping provides mapping data and support methods for this translation.
418 */
419 class RuntimeEnumMapping implements EnumMapping {
420 RuntimeEnumMapping(DiagnosticPosition pos, TypeSymbol forEnum) {
421 this.forEnum = forEnum;
422 this.values = new LinkedHashMap<>();
423 this.pos = pos;
424 Name varName = names
425 .fromString(target.syntheticNameChar() +
426 "SwitchMap" +
427 target.syntheticNameChar() +
428 ClassWriter.externalize(forEnum.type.tsym.flatName().toString())
429 .replace('/', '.')
430 .replace('.', target.syntheticNameChar()));
431 ClassSymbol outerCacheClass = outerCacheClass();
432 this.mapVar = new VarSymbol(STATIC | SYNTHETIC | FINAL,
433 varName,
434 new ArrayType(syms.intType, syms.arrayClass),
435 outerCacheClass);
436 enterSynthetic(pos, mapVar, outerCacheClass.members());
437 }
438
439 DiagnosticPosition pos = null;
440
441 // the next value to use
442 int next = 1; // 0 (unused map elements) go to the default label
443
444 // the enum for which this is a map
445 final TypeSymbol forEnum;
446
447 // the field containing the map
448 final VarSymbol mapVar;
449
450 // the mapped values
451 final Map<VarSymbol,Integer> values;
452
453 @Override
454 public JCExpression switchValue(JCExpression ordinalExpr) {
455 return make.Indexed(mapVar, ordinalExpr);
456 }
457
458 @Override
459 public JCLiteral caseValue(VarSymbol v) {
460 Integer result = values.get(v);
461 if (result == null)
462 values.put(v, result = next++);
463 return make.Literal(result);
464 }
465
466 // generate the field initializer for the map
467 @Override
468 public void translate() {
469 boolean prevAllowProtectedAccess = attrEnv.info.allowProtectedAccess;
470 try {
471 make.at(pos.getStartPosition());
472 attrEnv.info.allowProtectedAccess = true;
473 JCClassDecl owner = classDef((ClassSymbol)mapVar.owner);
474
475 // synthetic static final int[] $SwitchMap$Color = new int[Color.values().length];
476 MethodSymbol valuesMethod = lookupMethod(pos,
477 names.values,
478 forEnum.type,
479 List.nil());
480 JCExpression size = make // Color.values().length
481 .Select(make.App(make.QualIdent(valuesMethod)),
482 syms.lengthVar);
483 JCExpression mapVarInit = make
484 .NewArray(make.Type(syms.intType), List.of(size), null)
485 .setType(new ArrayType(syms.intType, syms.arrayClass));
486
487 // try { $SwitchMap$Color[red.ordinal()] = 1; } catch (java.lang.NoSuchFieldError ex) {}
488 ListBuffer<JCStatement> stmts = new ListBuffer<>();
489 Symbol ordinalMethod = lookupMethod(pos,
490 names.ordinal,
491 forEnum.type,
492 List.nil());
493 List<JCCatch> catcher = List.<JCCatch>nil()
494 .prepend(make.Catch(make.VarDef(new VarSymbol(PARAMETER, names.ex,
495 syms.noSuchFieldErrorType,
496 syms.noSymbol),
497 null),
498 make.Block(0, List.nil())));
499 for (Map.Entry<VarSymbol,Integer> e : values.entrySet()) {
500 VarSymbol enumerator = e.getKey();
501 Integer mappedValue = e.getValue();
502 JCExpression assign = make
503 .Assign(make.Indexed(mapVar,
504 make.App(make.Select(make.QualIdent(enumerator),
505 ordinalMethod))),
506 make.Literal(mappedValue))
507 .setType(syms.intType);
508 JCStatement exec = make.Exec(assign);
509 JCStatement _try = make.Try(make.Block(0, List.of(exec)), catcher, null);
510 stmts.append(_try);
511 }
512
513 owner.defs = owner.defs
514 .prepend(make.Block(STATIC, stmts.toList()))
515 .prepend(make.VarDef(mapVar, mapVarInit));
516 } finally {
517 attrEnv.info.allowProtectedAccess = prevAllowProtectedAccess;
518 }
519 }
520 }
521
522
523 /* ************************************************************************
524 * Tree building blocks
525 *************************************************************************/
526
527 /** Equivalent to make.at(pos.getStartPosition()) with side effect of caching
528 * pos as make_pos, for use in diagnostics.
529 **/
530 TreeMaker make_at(DiagnosticPosition pos) {
531 make_pos = pos;
532 return make.at(pos);
533 }
534
535 /** Make an attributed tree representing a literal. This will be an
536 * Ident node in the case of boolean literals, a Literal node in all
537 * other cases.
538 * @param type The literal's type.
539 * @param value The literal's value.
540 */
541 JCExpression makeLit(Type type, Object value) {
542 return make.Literal(type.getTag(), value).setType(type.constType(value));
543 }
544
545 /** Make an attributed tree representing null.
546 */
547 JCExpression makeNull() {
548 return makeLit(syms.botType, null);
549 }
550
551 /** Make an attributed class instance creation expression.
552 * @param ctype The class type.
553 * @param args The constructor arguments.
554 */
555 JCNewClass makeNewClass(Type ctype, List<JCExpression> args) {
556 JCNewClass tree = make.NewClass(null,
557 null, make.QualIdent(ctype.tsym), args, null);
558 tree.constructor = rs.resolveConstructor(
559 make_pos, attrEnv, ctype, TreeInfo.types(args), List.nil());
560 tree.type = ctype;
561 return tree;
562 }
563
564 /** Make an attributed unary expression.
565 * @param optag The operators tree tag.
566 * @param arg The operator's argument.
567 */
568 JCUnary makeUnary(JCTree.Tag optag, JCExpression arg) {
569 JCUnary tree = make.Unary(optag, arg);
570 tree.operator = operators.resolveUnary(tree, optag, arg.type);
571 tree.type = tree.operator.type.getReturnType();
572 return tree;
573 }
574
575 /** Make an attributed binary expression.
576 * @param optag The operators tree tag.
577 * @param lhs The operator's left argument.
578 * @param rhs The operator's right argument.
579 */
580 JCBinary makeBinary(JCTree.Tag optag, JCExpression lhs, JCExpression rhs) {
581 JCBinary tree = make.Binary(optag, lhs, rhs);
582 tree.operator = operators.resolveBinary(tree, optag, lhs.type, rhs.type);
583 tree.type = tree.operator.type.getReturnType();
584 return tree;
585 }
586
587 /** Make an attributed assignop expression.
588 * @param optag The operators tree tag.
589 * @param lhs The operator's left argument.
590 * @param rhs The operator's right argument.
591 */
592 JCAssignOp makeAssignop(JCTree.Tag optag, JCTree lhs, JCTree rhs) {
593 JCAssignOp tree = make.Assignop(optag, lhs, rhs);
594 tree.operator = operators.resolveBinary(tree, tree.getTag().noAssignOp(), lhs.type, rhs.type);
595 tree.type = lhs.type;
596 return tree;
597 }
598
599 /** Convert tree into string object, unless it has already a
600 * reference type..
601 */
602 JCExpression makeString(JCExpression tree) {
603 if (!tree.type.isPrimitiveOrVoid()) {
604 return tree;
605 } else {
606 Symbol valueOfSym = lookupMethod(tree.pos(),
607 names.valueOf,
608 syms.stringType,
609 List.of(tree.type));
610 return make.App(make.QualIdent(valueOfSym), List.of(tree));
611 }
612 }
613
614 /** Create an empty anonymous class definition and enter and complete
615 * its symbol. Return the class definition's symbol.
616 * and create
617 * @param flags The class symbol's flags
618 * @param owner The class symbol's owner
619 */
620 JCClassDecl makeEmptyClass(long flags, ClassSymbol owner) {
621 return makeEmptyClass(flags, owner, null, true);
622 }
623
624 JCClassDecl makeEmptyClass(long flags, ClassSymbol owner, Name flatname,
625 boolean addToDefs) {
626 // Create class symbol.
627 ClassSymbol c = syms.defineClass(names.empty, owner);
628 if (flatname != null) {
629 c.flatname = flatname;
630 } else {
631 c.flatname = chk.localClassName(c);
632 }
633 c.sourcefile = owner.sourcefile;
634 c.completer = Completer.NULL_COMPLETER;
635 c.members_field = WriteableScope.create(c);
636 c.flags_field = flags;
637 ClassType ctype = (ClassType) c.type;
638 ctype.supertype_field = syms.objectType;
639 ctype.interfaces_field = List.nil();
640
641 JCClassDecl odef = classDef(owner);
642
643 // Enter class symbol in owner scope and compiled table.
644 enterSynthetic(odef.pos(), c, owner.members());
645 chk.putCompiled(c);
646
647 // Create class definition tree.
648 JCClassDecl cdef = make.ClassDef(
649 make.Modifiers(flags), names.empty,
650 List.nil(),
651 null, List.nil(), List.nil());
652 cdef.sym = c;
653 cdef.type = c.type;
654
655 // Append class definition tree to owner's definitions.
656 if (addToDefs) odef.defs = odef.defs.prepend(cdef);
657 return cdef;
658 }
659
660 /* ************************************************************************
661 * Symbol manipulation utilities
662 *************************************************************************/
663
664 /** Enter a synthetic symbol in a given scope, but complain if there was already one there.
665 * @param pos Position for error reporting.
666 * @param sym The symbol.
667 * @param s The scope.
668 */
669 private void enterSynthetic(DiagnosticPosition pos, Symbol sym, WriteableScope s) {
670 s.enter(sym);
671 }
672
673 /** Create a fresh synthetic name within a given scope - the unique name is
674 * obtained by appending '$' chars at the end of the name until no match
675 * is found.
676 *
677 * @param name base name
678 * @param s scope in which the name has to be unique
679 * @return fresh synthetic name
680 */
681 private Name makeSyntheticName(Name name, Scope s) {
682 do {
683 name = name.append(
684 target.syntheticNameChar(),
685 names.empty);
686 } while (lookupSynthetic(name, s) != null);
687 return name;
688 }
689
690 /** Check whether synthetic symbols generated during lowering conflict
691 * with user-defined symbols.
692 *
693 * @param translatedTrees lowered class trees
694 */
695 void checkConflicts(List<JCTree> translatedTrees) {
696 for (JCTree t : translatedTrees) {
697 t.accept(conflictsChecker);
698 }
699 }
700
701 JCTree.Visitor conflictsChecker = new TreeScanner() {
702
703 TypeSymbol currentClass;
704
705 @Override
706 public void visitMethodDef(JCMethodDecl that) {
707 checkConflicts(that.pos(), that.sym, currentClass);
708 super.visitMethodDef(that);
709 }
710
711 @Override
712 public void visitVarDef(JCVariableDecl that) {
713 if (that.sym.owner.kind == TYP) {
714 checkConflicts(that.pos(), that.sym, currentClass);
715 }
716 super.visitVarDef(that);
717 }
718
719 @Override
720 public void visitClassDef(JCClassDecl that) {
721 TypeSymbol prevCurrentClass = currentClass;
722 currentClass = that.sym;
723 try {
724 super.visitClassDef(that);
725 }
726 finally {
727 currentClass = prevCurrentClass;
728 }
729 }
730
731 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) {
732 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) {
733 for (Symbol sym2 : ct.tsym.members().getSymbolsByName(sym.name, NON_RECURSIVE)) {
734 // VM allows methods and variables with differing types
735 if (sym.kind == sym2.kind &&
736 types.isSameType(types.erasure(sym.type), types.erasure(sym2.type)) &&
737 sym != sym2 &&
738 (sym.flags() & Flags.SYNTHETIC) != (sym2.flags() & Flags.SYNTHETIC) &&
739 (sym.flags() & BRIDGE) == 0 && (sym2.flags() & BRIDGE) == 0) {
740 syntheticError(pos, (sym2.flags() & SYNTHETIC) == 0 ? sym2 : sym);
741 return;
742 }
743 }
744 }
745 }
746
747 /** Report a conflict between a user symbol and a synthetic symbol.
748 */
749 private void syntheticError(DiagnosticPosition pos, Symbol sym) {
750 if (!sym.type.isErroneous()) {
751 log.error(pos, Errors.CannotGenerateClass(sym.location(), Fragments.SyntheticNameConflict(sym, sym.location())));
752 }
753 }
754 };
755
756 /** Look up a synthetic name in a given scope.
757 * @param s The scope.
758 * @param name The name.
759 */
760 private Symbol lookupSynthetic(Name name, Scope s) {
761 Symbol sym = s.findFirst(name);
762 return (sym==null || (sym.flags()&SYNTHETIC)==0) ? null : sym;
763 }
764
765 /** Look up a method in a given scope.
766 */
767 private MethodSymbol lookupMethod(DiagnosticPosition pos, Name name, Type qual, List<Type> args) {
768 return rs.resolveInternalMethod(pos, attrEnv, qual, name, args, List.nil());
769 }
770
771 /** Anon inner classes are used as access constructor tags.
772 * accessConstructorTag will use an existing anon class if one is available,
773 * and synthesize a class (with makeEmptyClass) if one is not available.
774 * However, there is a small possibility that an existing class will not
775 * be generated as expected if it is inside a conditional with a constant
776 * expression. If that is found to be the case, create an empty class tree here.
777 */
778 private void checkAccessConstructorTags() {
779 for (List<ClassSymbol> l = accessConstrTags; l.nonEmpty(); l = l.tail) {
780 ClassSymbol c = l.head;
781 if (isTranslatedClassAvailable(c))
782 continue;
783 // Create class definition tree.
784 // IDENTITY_TYPE will be interpreted as ACC_SUPER for older class files so we are fine
785 JCClassDecl cdec = makeEmptyClass(STATIC | SYNTHETIC | IDENTITY_TYPE,
786 c.outermostClass(), c.flatname, false);
787 swapAccessConstructorTag(c, cdec.sym);
788 translated.append(cdec);
789 }
790 }
791 // where
792 private boolean isTranslatedClassAvailable(ClassSymbol c) {
793 for (JCTree tree: translated) {
794 if (tree.hasTag(CLASSDEF)
795 && ((JCClassDecl) tree).sym == c) {
796 return true;
797 }
798 }
799 return false;
800 }
801
802 void swapAccessConstructorTag(ClassSymbol oldCTag, ClassSymbol newCTag) {
803 for (MethodSymbol methodSymbol : accessConstrs.values()) {
804 Assert.check(methodSymbol.type.hasTag(METHOD));
805 MethodType oldMethodType =
806 (MethodType)methodSymbol.type;
807 if (oldMethodType.argtypes.head.tsym == oldCTag)
808 methodSymbol.type =
809 types.createMethodTypeWithParameters(oldMethodType,
810 oldMethodType.getParameterTypes().tail
811 .prepend(newCTag.erasure(types)));
812 }
813 }
814
815 /* ************************************************************************
816 * Access methods
817 *************************************************************************/
818
819 /** A mapping from symbols to their access numbers.
820 */
821 private Map<Symbol,Integer> accessNums;
822
823 /** A mapping from symbols to an array of access symbols, indexed by
824 * access code.
825 */
826 private Map<Symbol,MethodSymbol[]> accessSyms;
827
828 /** A mapping from (constructor) symbols to access constructor symbols.
829 */
830 private Map<Symbol,MethodSymbol> accessConstrs;
831
832 /** A list of all class symbols used for access constructor tags.
833 */
834 private List<ClassSymbol> accessConstrTags;
835
836 /** A queue for all accessed symbols.
837 */
838 private ListBuffer<Symbol> accessed;
839
840 /** return access code for identifier,
841 * @param tree The tree representing the identifier use.
842 * @param enclOp The closest enclosing operation node of tree,
843 * null if tree is not a subtree of an operation.
844 */
845 private static int accessCode(JCTree tree, JCTree enclOp) {
846 if (enclOp == null)
847 return AccessCode.DEREF.code;
848 else if (enclOp.hasTag(ASSIGN) &&
849 tree == TreeInfo.skipParens(((JCAssign) enclOp).lhs))
850 return AccessCode.ASSIGN.code;
851 else if ((enclOp.getTag().isIncOrDecUnaryOp() || enclOp.getTag().isAssignop()) &&
852 tree == TreeInfo.skipParens(((JCOperatorExpression) enclOp).getOperand(LEFT)))
853 return (((JCOperatorExpression) enclOp).operator).getAccessCode(enclOp.getTag());
854 else
855 return AccessCode.DEREF.code;
856 }
857
858 /** Return binary operator that corresponds to given access code.
859 */
860 private OperatorSymbol binaryAccessOperator(int acode, Tag tag) {
861 return operators.lookupBinaryOp(op -> op.getAccessCode(tag) == acode);
862 }
863
864 /** Return tree tag for assignment operation corresponding
865 * to given binary operator.
866 */
867 private static JCTree.Tag treeTag(OperatorSymbol operator) {
868 switch (operator.opcode) {
869 case ByteCodes.ior: case ByteCodes.lor:
870 return BITOR_ASG;
871 case ByteCodes.ixor: case ByteCodes.lxor:
872 return BITXOR_ASG;
873 case ByteCodes.iand: case ByteCodes.land:
874 return BITAND_ASG;
875 case ByteCodes.ishl: case ByteCodes.lshl:
876 case ByteCodes.ishll: case ByteCodes.lshll:
877 return SL_ASG;
878 case ByteCodes.ishr: case ByteCodes.lshr:
879 case ByteCodes.ishrl: case ByteCodes.lshrl:
880 return SR_ASG;
881 case ByteCodes.iushr: case ByteCodes.lushr:
882 case ByteCodes.iushrl: case ByteCodes.lushrl:
883 return USR_ASG;
884 case ByteCodes.iadd: case ByteCodes.ladd:
885 case ByteCodes.fadd: case ByteCodes.dadd:
886 case ByteCodes.string_add:
887 return PLUS_ASG;
888 case ByteCodes.isub: case ByteCodes.lsub:
889 case ByteCodes.fsub: case ByteCodes.dsub:
890 return MINUS_ASG;
891 case ByteCodes.imul: case ByteCodes.lmul:
892 case ByteCodes.fmul: case ByteCodes.dmul:
893 return MUL_ASG;
894 case ByteCodes.idiv: case ByteCodes.ldiv:
895 case ByteCodes.fdiv: case ByteCodes.ddiv:
896 return DIV_ASG;
897 case ByteCodes.imod: case ByteCodes.lmod:
898 case ByteCodes.fmod: case ByteCodes.dmod:
899 return MOD_ASG;
900 default:
901 throw new AssertionError();
902 }
903 }
904
905 /** The name of the access method with number `anum' and access code `acode'.
906 */
907 Name accessName(int anum, int acode) {
908 return names.fromString(
909 "access" + target.syntheticNameChar() + anum + acode / 10 + acode % 10);
910 }
911
912 /** Return access symbol for a private or protected symbol from an inner class.
913 * @param sym The accessed private symbol.
914 * @param tree The accessing tree.
915 * @param enclOp The closest enclosing operation node of tree,
916 * null if tree is not a subtree of an operation.
917 * @param protAccess Is access to a protected symbol in another
918 * package?
919 * @param refSuper Is access via a (qualified) C.super?
920 */
921 MethodSymbol accessSymbol(Symbol sym, JCTree tree, JCTree enclOp,
922 boolean protAccess, boolean refSuper) {
923 ClassSymbol accOwner = refSuper && protAccess
924 // For access via qualified super (T.super.x), place the
925 // access symbol on T.
926 ? (ClassSymbol)((JCFieldAccess) tree).selected.type.tsym
927 // Otherwise pretend that the owner of an accessed
928 // protected symbol is the enclosing class of the current
929 // class which is a subclass of the symbol's owner.
930 : accessClass(sym, protAccess, tree);
931
932 Symbol vsym = sym;
933 if (sym.owner != accOwner) {
934 vsym = sym.clone(accOwner);
935 actualSymbols.put(vsym, sym);
936 }
937
938 Integer anum // The access number of the access method.
939 = accessNums.get(vsym);
940 if (anum == null) {
941 anum = accessed.length();
942 accessNums.put(vsym, anum);
943 accessSyms.put(vsym, new MethodSymbol[AccessCode.numberOfAccessCodes]);
944 accessed.append(vsym);
945 // System.out.println("accessing " + vsym + " in " + vsym.location());
946 }
947
948 int acode; // The access code of the access method.
949 List<Type> argtypes; // The argument types of the access method.
950 Type restype; // The result type of the access method.
951 List<Type> thrown; // The thrown exceptions of the access method.
952 switch (vsym.kind) {
953 case VAR:
954 acode = accessCode(tree, enclOp);
955 if (acode >= AccessCode.FIRSTASGOP.code) {
956 OperatorSymbol operator = binaryAccessOperator(acode, enclOp.getTag());
957 if (operator.opcode == string_add)
958 argtypes = List.of(syms.objectType);
959 else
960 argtypes = operator.type.getParameterTypes().tail;
961 } else if (acode == AccessCode.ASSIGN.code)
962 argtypes = List.of(vsym.erasure(types));
963 else
964 argtypes = List.nil();
965 restype = vsym.erasure(types);
966 thrown = List.nil();
967 break;
968 case MTH:
969 acode = AccessCode.DEREF.code;
970 argtypes = vsym.erasure(types).getParameterTypes();
971 restype = vsym.erasure(types).getReturnType();
972 thrown = vsym.type.getThrownTypes();
973 break;
974 default:
975 throw new AssertionError();
976 }
977
978 // For references via qualified super, increment acode by one,
979 // making it odd.
980 if (protAccess && refSuper) acode++;
981
982 // Instance access methods get instance as first parameter.
983 // For protected symbols this needs to be the instance as a member
984 // of the type containing the accessed symbol, not the class
985 // containing the access method.
986 if ((vsym.flags() & STATIC) == 0) {
987 argtypes = argtypes.prepend(vsym.owner.erasure(types));
988 }
989 MethodSymbol[] accessors = accessSyms.get(vsym);
990 MethodSymbol accessor = accessors[acode];
991 if (accessor == null) {
992 accessor = new MethodSymbol(
993 STATIC | SYNTHETIC | (accOwner.isInterface() ? PUBLIC : 0),
994 accessName(anum.intValue(), acode),
995 new MethodType(argtypes, restype, thrown, syms.methodClass),
996 accOwner);
997 enterSynthetic(tree.pos(), accessor, accOwner.members());
998 accessors[acode] = accessor;
999 }
1000 return accessor;
1001 }
1002
1003 /** The qualifier to be used for accessing a symbol in an outer class.
1004 * This is either C.sym or C.this.sym, depending on whether or not
1005 * sym is static.
1006 * @param sym The accessed symbol.
1007 */
1008 JCExpression accessBase(DiagnosticPosition pos, Symbol sym) {
1009 return (sym.flags() & STATIC) != 0
1010 ? access(make.at(pos.getStartPosition()).QualIdent(sym.owner))
1011 : makeOwnerThis(pos, sym, true);
1012 }
1013
1014 /** Do we need an access method to reference private symbol?
1015 */
1016 boolean needsPrivateAccess(Symbol sym) {
1017 if (target.hasNestmateAccess()) {
1018 return false;
1019 }
1020 if ((sym.flags() & PRIVATE) == 0 || sym.owner == currentClass) {
1021 return false;
1022 } else if (sym.name == names.init && sym.owner.isDirectlyOrIndirectlyLocal()) {
1023 // private constructor in local class: relax protection
1024 sym.flags_field &= ~PRIVATE;
1025 return false;
1026 } else {
1027 return true;
1028 }
1029 }
1030
1031 /** Do we need an access method to reference symbol in other package?
1032 */
1033 boolean needsProtectedAccess(Symbol sym, JCTree tree) {
1034 if (disableProtectedAccessors) return false;
1035 if ((sym.flags() & PROTECTED) == 0 ||
1036 sym.owner.owner == currentClass.owner || // fast special case
1037 sym.packge() == currentClass.packge())
1038 return false;
1039 if (!currentClass.isSubClass(sym.owner, types))
1040 return true;
1041 if ((sym.flags() & STATIC) != 0 ||
1042 !tree.hasTag(SELECT) ||
1043 TreeInfo.name(((JCFieldAccess) tree).selected) == names._super)
1044 return false;
1045 return !((JCFieldAccess) tree).selected.type.tsym.isSubClass(currentClass, types);
1046 }
1047
1048 /** The class in which an access method for given symbol goes.
1049 * @param sym The access symbol
1050 * @param protAccess Is access to a protected symbol in another
1051 * package?
1052 */
1053 ClassSymbol accessClass(Symbol sym, boolean protAccess, JCTree tree) {
1054 if (protAccess) {
1055 Symbol qualifier = null;
1056 ClassSymbol c = currentClass;
1057 if (tree.hasTag(SELECT) && (sym.flags() & STATIC) == 0) {
1058 qualifier = ((JCFieldAccess) tree).selected.type.tsym;
1059 while (!qualifier.isSubClass(c, types)) {
1060 c = c.owner.enclClass();
1061 }
1062 return c;
1063 } else {
1064 while (!c.isSubClass(sym.owner, types)) {
1065 c = c.owner.enclClass();
1066 }
1067 }
1068 return c;
1069 } else {
1070 // the symbol is private
1071 return sym.owner.enclClass();
1072 }
1073 }
1074
1075 private boolean noClassDefIn(JCTree tree) {
1076 var scanner = new TreeScanner() {
1077 boolean noClassDef = true;
1078 @Override
1079 public void visitClassDef(JCClassDecl tree) {
1080 noClassDef = false;
1081 }
1082 };
1083 scanner.scan(tree);
1084 return scanner.noClassDef;
1085 }
1086
1087 private void addPrunedInfo(JCTree tree) {
1088 List<JCTree> infoList = prunedTree.get(currentClass);
1089 infoList = (infoList == null) ? List.of(tree) : infoList.prepend(tree);
1090 prunedTree.put(currentClass, infoList);
1091 }
1092
1093 /** Ensure that identifier is accessible, return tree accessing the identifier.
1094 * @param sym The accessed symbol.
1095 * @param tree The tree referring to the symbol.
1096 * @param enclOp The closest enclosing operation node of tree,
1097 * null if tree is not a subtree of an operation.
1098 * @param refSuper Is access via a (qualified) C.super?
1099 */
1100 JCExpression access(Symbol sym, JCExpression tree, JCExpression enclOp, boolean refSuper) {
1101 // Access a free variable via its proxy, or its proxy's proxy
1102 while (sym.kind == VAR && sym.owner.kind == MTH &&
1103 sym.owner.enclClass() != currentClass) {
1104 // A constant is replaced by its constant value.
1105 Object cv = ((VarSymbol)sym).getConstValue();
1106 if (cv != null) {
1107 make.at(tree.pos);
1108 return makeLit(sym.type, cv);
1109 }
1110 // Otherwise replace the variable by its proxy.
1111 sym = proxies.get(sym);
1112 Assert.check(sym != null && (sym.flags_field & FINAL) != 0);
1113 tree = make.at(tree.pos).Ident(sym);
1114 }
1115 JCExpression base = (tree.hasTag(SELECT)) ? ((JCFieldAccess) tree).selected : null;
1116 switch (sym.kind) {
1117 case TYP:
1118 if (sym.owner.kind != PCK) {
1119 // Convert type idents to
1120 // <flat name> or <package name> . <flat name>
1121 Name flatname = Convert.shortName(sym.flatName());
1122 while (base != null &&
1123 TreeInfo.symbol(base) != null &&
1124 TreeInfo.symbol(base).kind != PCK) {
1125 base = (base.hasTag(SELECT))
1126 ? ((JCFieldAccess) base).selected
1127 : null;
1128 }
1129 if (tree.hasTag(IDENT)) {
1130 ((JCIdent) tree).name = flatname;
1131 } else if (base == null) {
1132 tree = make.at(tree.pos).Ident(sym);
1133 ((JCIdent) tree).name = flatname;
1134 } else {
1135 ((JCFieldAccess) tree).selected = base;
1136 ((JCFieldAccess) tree).name = flatname;
1137 }
1138 }
1139 break;
1140 case MTH: case VAR:
1141 if (sym.owner.kind == TYP) {
1142
1143 // Access methods are required for
1144 // - private members,
1145 // - protected members in a superclass of an
1146 // enclosing class contained in another package.
1147 // - all non-private members accessed via a qualified super.
1148 boolean protAccess = refSuper && !needsPrivateAccess(sym)
1149 || needsProtectedAccess(sym, tree);
1150 boolean accReq = protAccess || needsPrivateAccess(sym);
1151
1152 // A base has to be supplied for
1153 // - simple identifiers accessing variables in outer classes.
1154 boolean baseReq =
1155 base == null &&
1156 sym.owner != syms.predefClass &&
1157 !sym.isMemberOf(currentClass, types);
1158
1159 if (accReq || baseReq) {
1160 make.at(tree.pos);
1161
1162 // Constants are replaced by their constant value.
1163 if (sym.kind == VAR) {
1164 Object cv = ((VarSymbol)sym).getConstValue();
1165 if (cv != null) {
1166 addPrunedInfo(tree);
1167 return makeLit(sym.type, cv);
1168 }
1169 }
1170
1171 // Private variables and methods are replaced by calls
1172 // to their access methods.
1173 if (accReq) {
1174 List<JCExpression> args = List.nil();
1175 if ((sym.flags() & STATIC) == 0) {
1176 // Instance access methods get instance
1177 // as first parameter.
1178 if (base == null)
1179 base = makeOwnerThis(tree.pos(), sym, true);
1180 args = args.prepend(base);
1181 base = null; // so we don't duplicate code
1182 }
1183 Symbol access = accessSymbol(sym, tree,
1184 enclOp, protAccess,
1185 refSuper);
1186 JCExpression receiver = make.Select(
1187 base != null ? base : make.QualIdent(access.owner),
1188 access);
1189 return make.App(receiver, args);
1190
1191 // Other accesses to members of outer classes get a
1192 // qualifier.
1193 } else if (baseReq) {
1194 return make.at(tree.pos).Select(
1195 accessBase(tree.pos(), sym), sym).setType(tree.type);
1196 }
1197 }
1198 }
1199 }
1200 return tree;
1201 }
1202
1203 /** Ensure that identifier is accessible, return tree accessing the identifier.
1204 * @param tree The identifier tree.
1205 */
1206 JCExpression access(JCExpression tree) {
1207 Symbol sym = TreeInfo.symbol(tree);
1208 return sym == null ? tree : access(sym, tree, null, false);
1209 }
1210
1211 /** Return access constructor for a private constructor,
1212 * or the constructor itself, if no access constructor is needed.
1213 * @param pos The position to report diagnostics, if any.
1214 * @param constr The private constructor.
1215 */
1216 Symbol accessConstructor(DiagnosticPosition pos, Symbol constr) {
1217 if (needsPrivateAccess(constr)) {
1218 ClassSymbol accOwner = constr.owner.enclClass();
1219 MethodSymbol aconstr = accessConstrs.get(constr);
1220 if (aconstr == null) {
1221 List<Type> argtypes = constr.type.getParameterTypes();
1222 if ((accOwner.flags_field & ENUM) != 0)
1223 argtypes = argtypes
1224 .prepend(syms.intType)
1225 .prepend(syms.stringType);
1226 aconstr = new MethodSymbol(
1227 SYNTHETIC,
1228 names.init,
1229 new MethodType(
1230 argtypes.append(
1231 accessConstructorTag().erasure(types)),
1232 constr.type.getReturnType(),
1233 constr.type.getThrownTypes(),
1234 syms.methodClass),
1235 accOwner);
1236 enterSynthetic(pos, aconstr, accOwner.members());
1237 accessConstrs.put(constr, aconstr);
1238 accessed.append(constr);
1239 }
1240 return aconstr;
1241 } else {
1242 return constr;
1243 }
1244 }
1245
1246 /** Return an anonymous class nested in this toplevel class.
1247 */
1248 ClassSymbol accessConstructorTag() {
1249 ClassSymbol topClass = currentClass.outermostClass();
1250 ModuleSymbol topModle = topClass.packge().modle;
1251 for (int i = 1; ; i++) {
1252 Name flatname = names.fromString("" + topClass.getQualifiedName() +
1253 target.syntheticNameChar() +
1254 i);
1255 ClassSymbol ctag = chk.getCompiled(topModle, flatname);
1256 if (ctag == null)
1257 // IDENTITY_TYPE will be interpreted as ACC_SUPER for older class files so we are fine
1258 ctag = makeEmptyClass(STATIC | SYNTHETIC | IDENTITY_TYPE, topClass).sym;
1259 else if (!ctag.isAnonymous())
1260 continue;
1261 // keep a record of all tags, to verify that all are generated as required
1262 accessConstrTags = accessConstrTags.prepend(ctag);
1263 return ctag;
1264 }
1265 }
1266
1267 /** Add all required access methods for a private symbol to enclosing class.
1268 * @param sym The symbol.
1269 */
1270 void makeAccessible(Symbol sym) {
1271 JCClassDecl cdef = classDef(sym.owner.enclClass());
1272 if (cdef == null) Assert.error("class def not found: " + sym + " in " + sym.owner);
1273 if (sym.name == names.init) {
1274 cdef.defs = cdef.defs.prepend(
1275 accessConstructorDef(cdef.pos, sym, accessConstrs.get(sym)));
1276 } else {
1277 MethodSymbol[] accessors = accessSyms.get(sym);
1278 for (int i = 0; i < AccessCode.numberOfAccessCodes; i++) {
1279 if (accessors[i] != null)
1280 cdef.defs = cdef.defs.prepend(
1281 accessDef(cdef.pos, sym, accessors[i], i));
1282 }
1283 }
1284 }
1285
1286 /** Construct definition of an access method.
1287 * @param pos The source code position of the definition.
1288 * @param vsym The private or protected symbol.
1289 * @param accessor The access method for the symbol.
1290 * @param acode The access code.
1291 */
1292 JCTree accessDef(int pos, Symbol vsym, MethodSymbol accessor, int acode) {
1293 // System.err.println("access " + vsym + " with " + accessor);//DEBUG
1294 currentClass = vsym.owner.enclClass();
1295 make.at(pos);
1296 JCMethodDecl md = make.MethodDef(accessor, null);
1297
1298 // Find actual symbol
1299 Symbol sym = actualSymbols.get(vsym);
1300 if (sym == null) sym = vsym;
1301
1302 JCExpression ref; // The tree referencing the private symbol.
1303 List<JCExpression> args; // Any additional arguments to be passed along.
1304 if ((sym.flags() & STATIC) != 0) {
1305 ref = make.Ident(sym);
1306 args = make.Idents(md.params);
1307 } else {
1308 JCExpression site = make.Ident(md.params.head);
1309 if (acode % 2 != 0) {
1310 //odd access codes represent qualified super accesses - need to
1311 //emit reference to the direct superclass, even if the referred
1312 //member is from an indirect superclass (JLS 13.1)
1313 site.setType(types.erasure(types.supertype(vsym.owner.enclClass().type)));
1314 }
1315 ref = make.Select(site, sym);
1316 args = make.Idents(md.params.tail);
1317 }
1318 JCStatement stat; // The statement accessing the private symbol.
1319 if (sym.kind == VAR) {
1320 // Normalize out all odd access codes by taking floor modulo 2:
1321 int acode1 = acode - (acode & 1);
1322
1323 JCExpression expr; // The access method's return value.
1324 AccessCode aCode = AccessCode.getFromCode(acode1);
1325 switch (aCode) {
1326 case DEREF:
1327 expr = ref;
1328 break;
1329 case ASSIGN:
1330 expr = make.Assign(ref, args.head);
1331 break;
1332 case PREINC: case POSTINC: case PREDEC: case POSTDEC:
1333 expr = makeUnary(aCode.tag, ref);
1334 break;
1335 default:
1336 expr = make.Assignop(
1337 treeTag(binaryAccessOperator(acode1, JCTree.Tag.NO_TAG)), ref, args.head);
1338 ((JCAssignOp) expr).operator = binaryAccessOperator(acode1, JCTree.Tag.NO_TAG);
1339 }
1340 stat = make.Return(expr.setType(sym.type));
1341 } else {
1342 stat = make.Call(make.App(ref, args));
1343 }
1344 md.body = make.Block(0, List.of(stat));
1345
1346 // Make sure all parameters, result types and thrown exceptions
1347 // are accessible.
1348 for (List<JCVariableDecl> l = md.params; l.nonEmpty(); l = l.tail)
1349 l.head.vartype = access(l.head.vartype);
1350 md.restype = access(md.restype);
1351 for (List<JCExpression> l = md.thrown; l.nonEmpty(); l = l.tail)
1352 l.head = access(l.head);
1353
1354 return md;
1355 }
1356
1357 /** Construct definition of an access constructor.
1358 * @param pos The source code position of the definition.
1359 * @param constr The private constructor.
1360 * @param accessor The access method for the constructor.
1361 */
1362 JCTree accessConstructorDef(int pos, Symbol constr, MethodSymbol accessor) {
1363 make.at(pos);
1364 JCMethodDecl md = make.MethodDef(accessor,
1365 accessor.externalType(types),
1366 null);
1367 JCIdent callee = make.Ident(names._this);
1368 callee.sym = constr;
1369 callee.type = constr.type;
1370 md.body =
1371 make.Block(0, List.of(
1372 make.Call(
1373 make.App(
1374 callee,
1375 make.Idents(md.params.reverse().tail.reverse())))));
1376 return md;
1377 }
1378
1379 /* ************************************************************************
1380 * Free variables proxies and this$n
1381 *************************************************************************/
1382
1383 /** A map which allows to retrieve the translated proxy variable for any given symbol of an
1384 * enclosing scope that is accessed (the accessed symbol could be the synthetic 'this$n' symbol).
1385 * Inside a constructor, the map temporarily overrides entries corresponding to proxies and any
1386 * 'this$n' symbols, where they represent the constructor parameters.
1387 */
1388 Map<Symbol, Symbol> proxies;
1389
1390 /** A scope containing all unnamed resource variables/saved
1391 * exception variables for translated TWR blocks
1392 */
1393 WriteableScope twrVars;
1394
1395 /** A stack containing the this$n field of the currently translated
1396 * classes (if needed) in innermost first order.
1397 * Inside a constructor, proxies and any this$n symbol are duplicated
1398 * in an additional innermost scope, where they represent the constructor
1399 * parameters.
1400 */
1401 List<VarSymbol> outerThisStack;
1402
1403 /** The name of a free variable proxy.
1404 */
1405 Name proxyName(Name name, int index) {
1406 Name proxyName = names.fromString("val" + target.syntheticNameChar() + name);
1407 if (index > 0) {
1408 proxyName = proxyName.append(names.fromString("" + target.syntheticNameChar() + index));
1409 }
1410 return proxyName;
1411 }
1412
1413 /** Proxy definitions for all free variables in given list, in reverse order.
1414 * @param pos The source code position of the definition.
1415 * @param freevars The free variables.
1416 * @param owner The class in which the definitions go.
1417 * @param additionalFlags Any additional flags
1418 */
1419 List<JCVariableDecl> freevarDefs(int pos, List<VarSymbol> freevars, Symbol owner) {
1420 return freevarDefs(pos, freevars, owner, LOCAL_CAPTURE_FIELD);
1421 }
1422
1423 List<JCVariableDecl> freevarDefs(int pos, List<VarSymbol> freevars, Symbol owner,
1424 long additionalFlags) {
1425 long flags = FINAL | SYNTHETIC | additionalFlags;
1426 List<JCVariableDecl> defs = List.nil();
1427 Set<Name> proxyNames = new HashSet<>();
1428 for (List<VarSymbol> l = freevars; l.nonEmpty(); l = l.tail) {
1429 VarSymbol v = l.head;
1430 int index = 0;
1431 Name proxyName;
1432 do {
1433 proxyName = proxyName(v.name, index++);
1434 } while (!proxyNames.add(proxyName));
1435 VarSymbol proxy = new VarSymbol(
1436 flags, proxyName, v.erasure(types), owner) {
1437 @Override
1438 public Symbol baseSymbol() {
1439 return v;
1440 }
1441 };
1442 proxies.put(v, proxy);
1443 JCVariableDecl vd = make.at(pos).VarDef(proxy, null);
1444 vd.vartype = access(vd.vartype);
1445 defs = defs.prepend(vd);
1446 }
1447 return defs;
1448 }
1449
1450 /** The name of a this$n field
1451 * @param type The class referenced by the this$n field
1452 */
1453 Name outerThisName(Type type, Symbol owner) {
1454 Type t = type.getEnclosingType();
1455 int nestingLevel = 0;
1456 while (t.hasTag(CLASS)) {
1457 t = t.getEnclosingType();
1458 nestingLevel++;
1459 }
1460 Name result = names.fromString("this" + target.syntheticNameChar() + nestingLevel);
1461 while (owner.kind == TYP && ((ClassSymbol)owner).members().findFirst(result) != null)
1462 result = names.fromString(result.toString() + target.syntheticNameChar());
1463 return result;
1464 }
1465
1466 private VarSymbol makeOuterThisVarSymbol(Symbol owner, long flags) {
1467 Type target = owner.innermostAccessibleEnclosingClass().erasure(types);
1468 // Set NOOUTERTHIS for all synthetic outer instance variables, and unset
1469 // it when the variable is accessed. If the variable is never accessed,
1470 // we skip creating an outer instance field and saving the constructor
1471 // parameter to it.
1472 VarSymbol outerThis =
1473 new VarSymbol(flags | NOOUTERTHIS, outerThisName(target, owner), target, owner);
1474 outerThisStack = outerThisStack.prepend(outerThis);
1475 return outerThis;
1476 }
1477
1478 private JCVariableDecl makeOuterThisVarDecl(int pos, VarSymbol sym) {
1479 JCVariableDecl vd = make.at(pos).VarDef(sym, null);
1480 vd.vartype = access(vd.vartype);
1481 return vd;
1482 }
1483
1484 /** Definition for this$n field.
1485 * @param pos The source code position of the definition.
1486 * @param owner The method in which the definition goes.
1487 */
1488 JCVariableDecl outerThisDef(int pos, MethodSymbol owner) {
1489 ClassSymbol c = owner.enclClass();
1490 boolean isMandated =
1491 // Anonymous constructors
1492 (owner.isConstructor() && owner.isAnonymous()) ||
1493 // Constructors of non-private inner member classes
1494 (owner.isConstructor() && c.isInner() &&
1495 !c.isPrivate() && !c.isStatic());
1496 long flags =
1497 FINAL | (isMandated ? MANDATED : SYNTHETIC) | PARAMETER;
1498 VarSymbol outerThis = makeOuterThisVarSymbol(owner, flags);
1499 owner.extraParams = owner.extraParams.prepend(outerThis);
1500 return makeOuterThisVarDecl(pos, outerThis);
1501 }
1502
1503 /** Definition for this$n field.
1504 * @param pos The source code position of the definition.
1505 * @param owner The class in which the definition goes.
1506 */
1507 JCVariableDecl outerThisDef(int pos, ClassSymbol owner) {
1508 VarSymbol outerThis = makeOuterThisVarSymbol(owner, FINAL | SYNTHETIC | (allowValueClasses && owner.isValueClass() ? STRICT : 0));
1509 return makeOuterThisVarDecl(pos, outerThis);
1510 }
1511
1512 /** Return a list of trees that load the free variables in given list,
1513 * in reverse order.
1514 * @param pos The source code position to be used for the trees.
1515 * @param freevars The list of free variables.
1516 */
1517 List<JCExpression> loadFreevars(DiagnosticPosition pos, List<VarSymbol> freevars) {
1518 List<JCExpression> args = List.nil();
1519 for (List<VarSymbol> l = freevars; l.nonEmpty(); l = l.tail)
1520 args = args.prepend(loadFreevar(pos, l.head));
1521 return args;
1522 }
1523 //where
1524 JCExpression loadFreevar(DiagnosticPosition pos, VarSymbol v) {
1525 return access(v, make.at(pos).Ident(v), null, false);
1526 }
1527
1528 /** Construct a tree simulating the expression {@code C.this}.
1529 * @param pos The source code position to be used for the tree.
1530 * @param c The qualifier class.
1531 */
1532 JCExpression makeThis(DiagnosticPosition pos, TypeSymbol c) {
1533 if (currentClass == c) {
1534 // in this case, `this' works fine
1535 return make.at(pos).This(c.erasure(types));
1536 } else {
1537 // need to go via this$n
1538 return makeOuterThis(pos, c);
1539 }
1540 }
1541
1542 /**
1543 * Optionally replace a try statement with the desugaring of a
1544 * try-with-resources statement. The canonical desugaring of
1545 *
1546 * try ResourceSpecification
1547 * Block
1548 *
1549 * is
1550 *
1551 * {
1552 * final VariableModifiers_minus_final R #resource = Expression;
1553 *
1554 * try ResourceSpecificationtail
1555 * Block
1556 * } body-only-finally {
1557 * if (#resource != null) //nullcheck skipped if Expression is provably non-null
1558 * #resource.close();
1559 * } catch (Throwable #primaryException) {
1560 * if (#resource != null) //nullcheck skipped if Expression is provably non-null
1561 * try {
1562 * #resource.close();
1563 * } catch (Throwable #suppressedException) {
1564 * #primaryException.addSuppressed(#suppressedException);
1565 * }
1566 * throw #primaryException;
1567 * }
1568 * }
1569 *
1570 * @param tree The try statement to inspect.
1571 * @return a desugared try-with-resources tree, or the original
1572 * try block if there are no resources to manage.
1573 */
1574 JCTree makeTwrTry(JCTry tree) {
1575 make_at(tree.pos());
1576 twrVars = twrVars.dup();
1577 JCBlock twrBlock = makeTwrBlock(tree.resources, tree.body, 0);
1578 if (tree.catchers.isEmpty() && tree.finalizer == null)
1579 result = translate(twrBlock);
1580 else
1581 result = translate(make.Try(twrBlock, tree.catchers, tree.finalizer));
1582 twrVars = twrVars.leave();
1583 return result;
1584 }
1585
1586 private JCBlock makeTwrBlock(List<JCTree> resources, JCBlock block, int depth) {
1587 if (resources.isEmpty())
1588 return block;
1589
1590 // Add resource declaration or expression to block statements
1591 ListBuffer<JCStatement> stats = new ListBuffer<>();
1592 JCTree resource = resources.head;
1593 JCExpression resourceUse;
1594 boolean resourceNonNull;
1595 if (resource instanceof JCVariableDecl variableDecl) {
1596 resourceUse = make.Ident(variableDecl.sym).setType(resource.type);
1597 resourceNonNull = variableDecl.init != null && TreeInfo.skipParens(variableDecl.init).hasTag(NEWCLASS);
1598 stats.add(variableDecl);
1599 } else {
1600 Assert.check(resource instanceof JCExpression);
1601 VarSymbol syntheticTwrVar =
1602 new VarSymbol(SYNTHETIC | FINAL,
1603 makeSyntheticName(names.fromString("twrVar" +
1604 depth), twrVars),
1605 (resource.type.hasTag(BOT)) ?
1606 syms.autoCloseableType : resource.type,
1607 currentMethodSym);
1608 twrVars.enter(syntheticTwrVar);
1609 JCVariableDecl syntheticTwrVarDecl =
1610 make.VarDef(syntheticTwrVar, (JCExpression)resource);
1611 resourceUse = (JCExpression)make.Ident(syntheticTwrVar);
1612 resourceNonNull = false;
1613 stats.add(syntheticTwrVarDecl);
1614 }
1615
1616 //create (semi-) finally block that will be copied into the main try body:
1617 int oldPos = make.pos;
1618 make.at(TreeInfo.endPos(block));
1619
1620 // if (#resource != null) { #resource.close(); }
1621 JCStatement bodyCloseStatement = makeResourceCloseInvocation(resourceUse);
1622
1623 if (!resourceNonNull) {
1624 bodyCloseStatement = make.If(makeNonNullCheck(resourceUse),
1625 bodyCloseStatement,
1626 null);
1627 }
1628
1629 JCBlock finallyClause = make.Block(BODY_ONLY_FINALIZE, List.of(bodyCloseStatement));
1630 make.at(oldPos);
1631
1632 // Create catch clause that saves exception, closes the resource and then rethrows the exception:
1633 VarSymbol primaryException =
1634 new VarSymbol(FINAL|SYNTHETIC,
1635 names.fromString("t" +
1636 target.syntheticNameChar()),
1637 syms.throwableType,
1638 currentMethodSym);
1639 JCVariableDecl primaryExceptionDecl = make.VarDef(primaryException, null);
1640
1641 // close resource:
1642 // try {
1643 // #resource.close();
1644 // } catch (Throwable #suppressedException) {
1645 // #primaryException.addSuppressed(#suppressedException);
1646 // }
1647 VarSymbol suppressedException =
1648 new VarSymbol(SYNTHETIC, make.paramName(2),
1649 syms.throwableType,
1650 currentMethodSym);
1651 JCStatement addSuppressedStatement =
1652 make.Exec(makeCall(make.Ident(primaryException),
1653 names.addSuppressed,
1654 List.of(make.Ident(suppressedException))));
1655 JCBlock closeResourceTryBlock =
1656 make.Block(0L, List.of(makeResourceCloseInvocation(resourceUse)));
1657 JCVariableDecl catchSuppressedDecl = make.VarDef(suppressedException, null);
1658 JCBlock catchSuppressedBlock = make.Block(0L, List.of(addSuppressedStatement));
1659 List<JCCatch> catchSuppressedClauses =
1660 List.of(make.Catch(catchSuppressedDecl, catchSuppressedBlock));
1661 JCTry closeResourceTry = make.Try(closeResourceTryBlock, catchSuppressedClauses, null);
1662 closeResourceTry.finallyCanCompleteNormally = true;
1663
1664 JCStatement exceptionalCloseStatement = closeResourceTry;
1665
1666 if (!resourceNonNull) {
1667 // if (#resource != null) { }
1668 exceptionalCloseStatement = make.If(makeNonNullCheck(resourceUse),
1669 exceptionalCloseStatement,
1670 null);
1671 }
1672
1673 JCStatement exceptionalRethrow = make.Throw(make.Ident(primaryException));
1674 JCBlock exceptionalCloseBlock = make.Block(0L, List.of(exceptionalCloseStatement, exceptionalRethrow));
1675 JCCatch exceptionalCatchClause = make.Catch(primaryExceptionDecl, exceptionalCloseBlock);
1676
1677 //create the main try statement with the close:
1678 JCTry outerTry = make.Try(makeTwrBlock(resources.tail, block, depth + 1),
1679 List.of(exceptionalCatchClause),
1680 finallyClause);
1681
1682 outerTry.finallyCanCompleteNormally = true;
1683 stats.add(outerTry);
1684
1685 JCBlock newBlock = make.Block(0L, stats.toList());
1686 return newBlock;
1687 }
1688
1689 private JCStatement makeResourceCloseInvocation(JCExpression resource) {
1690 // convert to AutoCloseable if needed
1691 if (types.asSuper(resource.type, syms.autoCloseableType.tsym) == null) {
1692 resource = convert(resource, syms.autoCloseableType);
1693 }
1694
1695 // create resource.close() method invocation
1696 JCExpression resourceClose = makeCall(resource,
1697 names.close,
1698 List.nil());
1699 return make.Exec(resourceClose);
1700 }
1701
1702 private JCExpression makeNonNullCheck(JCExpression expression) {
1703 return makeBinary(NE, expression, makeNull());
1704 }
1705
1706 /** Construct a tree that represents the outer instance
1707 * {@code C.this}. Never pick the current `this'.
1708 * @param pos The source code position to be used for the tree.
1709 * @param c The qualifier class.
1710 */
1711 JCExpression makeOuterThis(DiagnosticPosition pos, TypeSymbol c) {
1712 List<VarSymbol> ots = outerThisStack;
1713 if (ots.isEmpty()) {
1714 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1715 return makeNull();
1716 }
1717 VarSymbol ot = ots.head;
1718 JCExpression tree = access(make.at(pos).Ident(ot));
1719 ot.flags_field &= ~NOOUTERTHIS;
1720 TypeSymbol otc = ot.type.tsym;
1721 while (otc != c) {
1722 do {
1723 ots = ots.tail;
1724 if (ots.isEmpty()) {
1725 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1726 Assert.error(); // should have been caught in Attr
1727 return tree;
1728 }
1729 ot = ots.head;
1730 } while (ot.owner != otc);
1731 if (otc.owner.kind != PCK && !otc.hasOuterInstance()) {
1732 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1733 Assert.error(); // should have been caught in Attr
1734 return makeNull();
1735 }
1736 tree = access(make.at(pos).Select(tree, ot));
1737 ot.flags_field &= ~NOOUTERTHIS;
1738 otc = ot.type.tsym;
1739 }
1740 return tree;
1741 }
1742
1743 /** Construct a tree that represents the closest outer instance
1744 * {@code C.this} such that the given symbol is a member of C.
1745 * @param pos The source code position to be used for the tree.
1746 * @param sym The accessed symbol.
1747 * @param preciseMatch should we accept a type that is a subtype of
1748 * sym's owner, even if it doesn't contain sym
1749 * due to hiding, overriding, or non-inheritance
1750 * due to protection?
1751 */
1752 JCExpression makeOwnerThis(DiagnosticPosition pos, Symbol sym, boolean preciseMatch) {
1753 if (preciseMatch ? sym.isMemberOf(currentClass, types)
1754 : currentClass.isSubClass(sym.owner, types)) {
1755 // in this case, `this' works fine
1756 return make.at(pos).This(currentClass.erasure(types));
1757 } else {
1758 // need to go via this$n
1759 return makeOwnerThisN(pos, sym, preciseMatch);
1760 }
1761 }
1762
1763 /**
1764 * Similar to makeOwnerThis but will never pick "this".
1765 */
1766 JCExpression makeOwnerThisN(DiagnosticPosition pos, Symbol sym, boolean preciseMatch) {
1767 Symbol c = sym.owner;
1768 List<VarSymbol> ots = outerThisStack;
1769 if (ots.isEmpty()) {
1770 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1771 return makeNull();
1772 }
1773 VarSymbol ot = ots.head;
1774 JCExpression tree = access(make.at(pos).Ident(ot));
1775 ot.flags_field &= ~NOOUTERTHIS;
1776 TypeSymbol otc = ot.type.tsym;
1777 while (!(preciseMatch ? sym.isMemberOf(otc, types) : otc.isSubClass(sym.owner, types))) {
1778 do {
1779 ots = ots.tail;
1780 if (ots.isEmpty()) {
1781 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1782 return tree;
1783 }
1784 ot = ots.head;
1785 } while (ot.owner != otc);
1786 tree = access(make.at(pos).Select(tree, ot));
1787 ot.flags_field &= ~NOOUTERTHIS;
1788 otc = ot.type.tsym;
1789 }
1790 return tree;
1791 }
1792
1793 /** Return tree simulating the assignment {@code this.name = name}, where
1794 * name is the name of a free variable.
1795 */
1796 JCStatement initField(int pos, Symbol rhs, Symbol lhs) {
1797 Assert.check(rhs.owner.kind == MTH);
1798 Assert.check(rhs.owner.owner == lhs.owner);
1799 make.at(pos);
1800 return
1801 make.Exec(
1802 make.Assign(
1803 make.Select(make.This(lhs.owner.erasure(types)), lhs),
1804 make.Ident(rhs)).setType(lhs.erasure(types)));
1805 }
1806
1807 /** Return tree simulating the assignment {@code this.this$n = this$n}.
1808 */
1809 JCStatement initOuterThis(int pos, VarSymbol rhs) {
1810 Assert.check(rhs.owner.kind == MTH);
1811 VarSymbol lhs = outerThisStack.head;
1812 Assert.check(rhs.owner.owner == lhs.owner);
1813 make.at(pos);
1814 return
1815 make.Exec(
1816 make.Assign(
1817 make.Select(make.This(lhs.owner.erasure(types)), lhs),
1818 make.Ident(rhs)).setType(lhs.erasure(types)));
1819 }
1820
1821 /* ************************************************************************
1822 * Code for .class
1823 *************************************************************************/
1824
1825 /** Return the symbol of a class to contain a cache of
1826 * compiler-generated statics such as class$ and the
1827 * $assertionsDisabled flag. We create an anonymous nested class
1828 * (unless one already exists) and return its symbol. However,
1829 * for backward compatibility in 1.4 and earlier we use the
1830 * top-level class itself.
1831 */
1832 private ClassSymbol outerCacheClass() {
1833 ClassSymbol clazz = outermostClassDef.sym;
1834 Scope s = clazz.members();
1835 for (Symbol sym : s.getSymbols(NON_RECURSIVE))
1836 if (sym.kind == TYP &&
1837 sym.name == names.empty &&
1838 (sym.flags() & INTERFACE) == 0) return (ClassSymbol) sym;
1839 // IDENTITY_TYPE will be interpreted as ACC_SUPER for older class files so we are fine
1840 return makeEmptyClass(STATIC | SYNTHETIC | IDENTITY_TYPE, clazz).sym;
1841 }
1842
1843 /** Create an attributed tree of the form left.name(). */
1844 private JCMethodInvocation makeCall(JCExpression left, Name name, List<JCExpression> args) {
1845 Assert.checkNonNull(left.type);
1846 Symbol funcsym = lookupMethod(make_pos, name, left.type,
1847 TreeInfo.types(args));
1848 return make.App(make.Select(left, funcsym), args);
1849 }
1850
1851 /** The tree simulating a T.class expression.
1852 * @param clazz The tree identifying type T.
1853 */
1854 private JCExpression classOf(JCTree clazz) {
1855 return classOfType(clazz.type, clazz.pos());
1856 }
1857
1858 private JCExpression classOfType(Type type, DiagnosticPosition pos) {
1859 switch (type.getTag()) {
1860 case BYTE: case SHORT: case CHAR: case INT: case LONG: case FLOAT:
1861 case DOUBLE: case BOOLEAN: case VOID:
1862 // replace with <BoxedClass>.TYPE
1863 ClassSymbol c = types.boxedClass(type);
1864 Symbol typeSym =
1865 rs.accessBase(
1866 rs.findIdentInType(pos, attrEnv, c.type, names.TYPE, KindSelector.VAR),
1867 pos, c.type, names.TYPE, true);
1868 if (typeSym.kind == VAR)
1869 ((VarSymbol)typeSym).getConstValue(); // ensure initializer is evaluated
1870 return make.QualIdent(typeSym);
1871 case CLASS: case ARRAY:
1872 VarSymbol sym = new VarSymbol(
1873 STATIC | PUBLIC | FINAL, names._class,
1874 syms.classType, type.tsym);
1875 return make_at(pos).Select(make.Type(type), sym);
1876 default:
1877 throw new AssertionError();
1878 }
1879 }
1880
1881 /* ************************************************************************
1882 * Code for enabling/disabling assertions.
1883 *************************************************************************/
1884
1885 private ClassSymbol assertionsDisabledClassCache;
1886
1887 /**Used to create an auxiliary class to hold $assertionsDisabled for interfaces.
1888 */
1889 private ClassSymbol assertionsDisabledClass() {
1890 if (assertionsDisabledClassCache != null) return assertionsDisabledClassCache;
1891
1892 // IDENTITY_TYPE will be interpreted as ACC_SUPER for older class files so we are fine
1893 assertionsDisabledClassCache = makeEmptyClass(STATIC | SYNTHETIC | IDENTITY_TYPE, outermostClassDef.sym).sym;
1894
1895 return assertionsDisabledClassCache;
1896 }
1897
1898 // This code is not particularly robust if the user has
1899 // previously declared a member named '$assertionsDisabled'.
1900 // The same faulty idiom also appears in the translation of
1901 // class literals above. We should report an error if a
1902 // previous declaration is not synthetic.
1903
1904 private JCExpression assertFlagTest(DiagnosticPosition pos) {
1905 // Outermost class may be either true class or an interface.
1906 ClassSymbol outermostClass = outermostClassDef.sym;
1907
1908 //only classes can hold a non-public field, look for a usable one:
1909 ClassSymbol container = !currentClass.isInterface() ? currentClass :
1910 assertionsDisabledClass();
1911
1912 VarSymbol assertDisabledSym =
1913 (VarSymbol)lookupSynthetic(dollarAssertionsDisabled,
1914 container.members());
1915 if (assertDisabledSym == null) {
1916 assertDisabledSym =
1917 new VarSymbol(STATIC | FINAL | SYNTHETIC,
1918 dollarAssertionsDisabled,
1919 syms.booleanType,
1920 container);
1921 enterSynthetic(pos, assertDisabledSym, container.members());
1922 Symbol desiredAssertionStatusSym = lookupMethod(pos,
1923 names.desiredAssertionStatus,
1924 types.erasure(syms.classType),
1925 List.nil());
1926 JCClassDecl containerDef = classDef(container);
1927 make_at(containerDef.pos());
1928 JCExpression notStatus = makeUnary(NOT, make.App(make.Select(
1929 classOfType(types.erasure(outermostClass.type),
1930 containerDef.pos()),
1931 desiredAssertionStatusSym)));
1932 JCVariableDecl assertDisabledDef = make.VarDef(assertDisabledSym,
1933 notStatus);
1934 containerDef.defs = containerDef.defs.prepend(assertDisabledDef);
1935
1936 if (currentClass.isInterface()) {
1937 //need to load the assertions enabled/disabled state while
1938 //initializing the interface:
1939 JCClassDecl currentClassDef = classDef(currentClass);
1940 make_at(currentClassDef.pos());
1941 JCStatement dummy = make.If(make.QualIdent(assertDisabledSym), make.Skip(), null);
1942 JCBlock clinit = make.Block(STATIC, List.of(dummy));
1943 currentClassDef.defs = currentClassDef.defs.prepend(clinit);
1944 }
1945 }
1946 make_at(pos);
1947 return makeUnary(NOT, make.Ident(assertDisabledSym));
1948 }
1949
1950
1951 /* ************************************************************************
1952 * Building blocks for let expressions
1953 *************************************************************************/
1954
1955 interface TreeBuilder {
1956 JCExpression build(JCExpression arg);
1957 }
1958
1959 /** Construct an expression using the builder, with the given rval
1960 * expression as an argument to the builder. However, the rval
1961 * expression must be computed only once, even if used multiple
1962 * times in the result of the builder. We do that by
1963 * constructing a "let" expression that saves the rvalue into a
1964 * temporary variable and then uses the temporary variable in
1965 * place of the expression built by the builder. The complete
1966 * resulting expression is of the form
1967 * <pre>
1968 * (let <b>TYPE</b> <b>TEMP</b> = <b>RVAL</b>;
1969 * in (<b>BUILDER</b>(<b>TEMP</b>)))
1970 * </pre>
1971 * where <code><b>TEMP</b></code> is a newly declared variable
1972 * in the let expression.
1973 */
1974 JCExpression abstractRval(JCExpression rval, Type type, TreeBuilder builder) {
1975 rval = TreeInfo.skipParens(rval);
1976 switch (rval.getTag()) {
1977 case LITERAL:
1978 return builder.build(rval);
1979 case IDENT:
1980 JCIdent id = (JCIdent) rval;
1981 if ((id.sym.flags() & FINAL) != 0 && id.sym.owner.kind == MTH)
1982 return builder.build(rval);
1983 }
1984 Name name = TreeInfo.name(rval);
1985 if (name == names._super || name == names._this)
1986 return builder.build(rval);
1987 VarSymbol var =
1988 new VarSymbol(FINAL|SYNTHETIC,
1989 names.fromString(
1990 target.syntheticNameChar()
1991 + "" + rval.hashCode()),
1992 type,
1993 currentMethodSym);
1994 rval = convert(rval,type);
1995 JCVariableDecl def = make.VarDef(var, rval); // XXX cast
1996 JCExpression built = builder.build(make.Ident(var));
1997 JCExpression res = make.LetExpr(def, built);
1998 res.type = built.type;
1999 return res;
2000 }
2001
2002 // same as above, with the type of the temporary variable computed
2003 JCExpression abstractRval(JCExpression rval, TreeBuilder builder) {
2004 return abstractRval(rval, rval.type, builder);
2005 }
2006
2007 // same as above, but for an expression that may be used as either
2008 // an rvalue or an lvalue. This requires special handling for
2009 // Select expressions, where we place the left-hand-side of the
2010 // select in a temporary, and for Indexed expressions, where we
2011 // place both the indexed expression and the index value in temps.
2012 JCExpression abstractLval(JCExpression lval, final TreeBuilder builder) {
2013 lval = TreeInfo.skipParens(lval);
2014 switch (lval.getTag()) {
2015 case IDENT:
2016 return builder.build(lval);
2017 case SELECT: {
2018 final JCFieldAccess s = (JCFieldAccess)lval;
2019 Symbol lid = TreeInfo.symbol(s.selected);
2020 if (lid != null && lid.kind == TYP) return builder.build(lval);
2021 return abstractRval(s.selected, selected -> builder.build(make.Select(selected, s.sym)));
2022 }
2023 case INDEXED: {
2024 final JCArrayAccess i = (JCArrayAccess)lval;
2025 return abstractRval(i.indexed, indexed -> abstractRval(i.index, syms.intType, index -> {
2026 JCExpression newLval = make.Indexed(indexed, index);
2027 newLval.setType(i.type);
2028 return builder.build(newLval);
2029 }));
2030 }
2031 case TYPECAST: {
2032 return abstractLval(((JCTypeCast)lval).expr, builder);
2033 }
2034 }
2035 throw new AssertionError(lval);
2036 }
2037
2038 // evaluate and discard the first expression, then evaluate the second.
2039 JCExpression makeComma(final JCExpression expr1, final JCExpression expr2) {
2040 JCExpression res = make.LetExpr(List.of(make.Exec(expr1)), expr2);
2041 res.type = expr2.type;
2042 return res;
2043 }
2044
2045 /* ************************************************************************
2046 * Translation methods
2047 *************************************************************************/
2048
2049 /** Visitor argument: enclosing operator node.
2050 */
2051 private JCExpression enclOp;
2052
2053 /** Visitor method: Translate a single node.
2054 * Attach the source position from the old tree to its replacement tree.
2055 */
2056 @Override
2057 public <T extends JCTree> T translate(T tree) {
2058 if (tree == null) {
2059 return null;
2060 } else {
2061 make_at(tree.pos());
2062 T result = super.translate(tree);
2063 if (endPosTable != null && result != tree) {
2064 endPosTable.replaceTree(tree, result);
2065 }
2066 return result;
2067 }
2068 }
2069
2070 /** Visitor method: Translate a single node, boxing or unboxing if needed.
2071 */
2072 public <T extends JCExpression> T translate(T tree, Type type) {
2073 return (tree == null) ? null : boxIfNeeded(translate(tree), type);
2074 }
2075
2076 /** Visitor method: Translate tree.
2077 */
2078 public <T extends JCTree> T translate(T tree, JCExpression enclOp) {
2079 JCExpression prevEnclOp = this.enclOp;
2080 this.enclOp = enclOp;
2081 T res = translate(tree);
2082 this.enclOp = prevEnclOp;
2083 return res;
2084 }
2085
2086 /** Visitor method: Translate list of trees.
2087 */
2088 public <T extends JCExpression> List<T> translate(List<T> trees, Type type) {
2089 if (trees == null) return null;
2090 for (List<T> l = trees; l.nonEmpty(); l = l.tail)
2091 l.head = translate(l.head, type);
2092 return trees;
2093 }
2094
2095 public void visitPackageDef(JCPackageDecl tree) {
2096 if (!needPackageInfoClass(tree))
2097 return;
2098
2099 long flags = Flags.ABSTRACT | Flags.INTERFACE;
2100 // package-info is marked SYNTHETIC in JDK 1.6 and later releases
2101 flags = flags | Flags.SYNTHETIC;
2102 ClassSymbol c = tree.packge.package_info;
2103 c.setAttributes(tree.packge);
2104 c.flags_field |= flags;
2105 ClassType ctype = (ClassType) c.type;
2106 ctype.supertype_field = syms.objectType;
2107 ctype.interfaces_field = List.nil();
2108 createInfoClass(tree.annotations, c);
2109 }
2110 // where
2111 private boolean needPackageInfoClass(JCPackageDecl pd) {
2112 switch (pkginfoOpt) {
2113 case ALWAYS:
2114 return true;
2115 case LEGACY:
2116 return pd.getAnnotations().nonEmpty();
2117 case NONEMPTY:
2118 for (Attribute.Compound a :
2119 pd.packge.getDeclarationAttributes()) {
2120 Attribute.RetentionPolicy p = types.getRetention(a);
2121 if (p != Attribute.RetentionPolicy.SOURCE)
2122 return true;
2123 }
2124 return false;
2125 }
2126 throw new AssertionError();
2127 }
2128
2129 public void visitModuleDef(JCModuleDecl tree) {
2130 ModuleSymbol msym = tree.sym;
2131 ClassSymbol c = msym.module_info;
2132 c.setAttributes(msym);
2133 c.flags_field |= Flags.MODULE;
2134 createInfoClass(List.nil(), tree.sym.module_info);
2135 }
2136
2137 private void createInfoClass(List<JCAnnotation> annots, ClassSymbol c) {
2138 long flags = Flags.ABSTRACT | Flags.INTERFACE;
2139 JCClassDecl infoClass =
2140 make.ClassDef(make.Modifiers(flags, annots),
2141 c.name, List.nil(),
2142 null, List.nil(), List.nil());
2143 infoClass.sym = c;
2144 translated.append(infoClass);
2145 }
2146
2147 public void visitClassDef(JCClassDecl tree) {
2148 Env<AttrContext> prevEnv = attrEnv;
2149 ClassSymbol currentClassPrev = currentClass;
2150 MethodSymbol currentMethodSymPrev = currentMethodSym;
2151
2152 currentClass = tree.sym;
2153 currentMethodSym = null;
2154 attrEnv = typeEnvs.remove(currentClass);
2155 if (attrEnv == null)
2156 attrEnv = prevEnv;
2157
2158 classdefs.put(currentClass, tree);
2159
2160 Map<Symbol, Symbol> prevProxies = proxies;
2161 proxies = new HashMap<>(proxies);
2162 List<VarSymbol> prevOuterThisStack = outerThisStack;
2163
2164 // If this is an enum definition
2165 if ((tree.mods.flags & ENUM) != 0 &&
2166 (types.supertype(currentClass.type).tsym.flags() & ENUM) == 0)
2167 visitEnumDef(tree);
2168
2169 if ((tree.mods.flags & RECORD) != 0) {
2170 visitRecordDef(tree);
2171 }
2172
2173 // If this is a nested class, define a this$n field for
2174 // it and add to proxies.
2175 JCVariableDecl otdef = null;
2176 if (currentClass.hasOuterInstance())
2177 otdef = outerThisDef(tree.pos, currentClass);
2178
2179 // If this is a local class, define proxies for all its free variables.
2180 List<JCVariableDecl> fvdefs = freevarDefs(
2181 tree.pos, freevars(currentClass), currentClass, allowValueClasses && currentClass.isValueClass() ? STRICT : LOCAL_CAPTURE_FIELD);
2182
2183 // Recursively translate superclass, interfaces.
2184 tree.extending = translate(tree.extending);
2185 tree.implementing = translate(tree.implementing);
2186
2187 if (currentClass.isDirectlyOrIndirectlyLocal()) {
2188 ClassSymbol encl = currentClass.owner.enclClass();
2189 if (encl.trans_local == null) {
2190 encl.trans_local = List.nil();
2191 }
2192 encl.trans_local = encl.trans_local.prepend(currentClass);
2193 }
2194
2195 // Recursively translate members, taking into account that new members
2196 // might be created during the translation and prepended to the member
2197 // list `tree.defs'.
2198 List<JCTree> seen = List.nil();
2199 while (tree.defs != seen) {
2200 List<JCTree> unseen = tree.defs;
2201 for (List<JCTree> l = unseen; l.nonEmpty() && l != seen; l = l.tail) {
2202 JCTree outermostMemberDefPrev = outermostMemberDef;
2203 if (outermostMemberDefPrev == null) outermostMemberDef = l.head;
2204 l.head = translate(l.head);
2205 outermostMemberDef = outermostMemberDefPrev;
2206 }
2207 seen = unseen;
2208 }
2209
2210 // Convert a protected modifier to public, mask static modifier.
2211 if ((tree.mods.flags & PROTECTED) != 0) tree.mods.flags |= PUBLIC;
2212 tree.mods.flags &= ClassFlags;
2213
2214 // Convert name to flat representation, replacing '.' by '$'.
2215 tree.name = Convert.shortName(currentClass.flatName());
2216
2217 // Add free variables proxy definitions to class.
2218
2219 for (List<JCVariableDecl> l = fvdefs; l.nonEmpty(); l = l.tail) {
2220 tree.defs = tree.defs.prepend(l.head);
2221 enterSynthetic(tree.pos(), l.head.sym, currentClass.members());
2222 }
2223 // If this$n was accessed, add the field definition and prepend
2224 // initializer code to any super() invocation to initialize it
2225 if (currentClass.hasOuterInstance() && shouldEmitOuterThis(currentClass)) {
2226 tree.defs = tree.defs.prepend(otdef);
2227 enterSynthetic(tree.pos(), otdef.sym, currentClass.members());
2228
2229 for (JCTree def : tree.defs) {
2230 if (TreeInfo.isConstructor(def)) {
2231 JCMethodDecl mdef = (JCMethodDecl)def;
2232 if (TreeInfo.hasConstructorCall(mdef, names._super)) {
2233 List<JCStatement> initializer = List.of(initOuterThis(mdef.body.pos, mdef.params.head.sym));
2234 TreeInfo.mapSuperCalls(mdef.body, supercall -> make.Block(0, initializer.append(supercall)));
2235 }
2236 }
2237 }
2238 }
2239
2240 proxies = prevProxies;
2241 outerThisStack = prevOuterThisStack;
2242
2243 // Append translated tree to `translated' queue.
2244 translated.append(tree);
2245
2246 attrEnv = prevEnv;
2247 currentClass = currentClassPrev;
2248 currentMethodSym = currentMethodSymPrev;
2249
2250 // Return empty block {} as a placeholder for an inner class.
2251 result = make_at(tree.pos()).Block(SYNTHETIC, List.nil());
2252 }
2253
2254 private boolean shouldEmitOuterThis(ClassSymbol sym) {
2255 if (!optimizeOuterThis) {
2256 // Optimization is disabled
2257 return true;
2258 }
2259 if ((outerThisStack.head.flags_field & NOOUTERTHIS) == 0) {
2260 // Enclosing instance field is used
2261 return true;
2262 }
2263 if (rs.isSerializable(sym.type)) {
2264 // Class is serializable
2265 return true;
2266 }
2267 return false;
2268 }
2269
2270 List<JCTree> generateMandatedAccessors(JCClassDecl tree) {
2271 List<JCVariableDecl> fields = TreeInfo.recordFields(tree);
2272 return tree.sym.getRecordComponents().stream()
2273 .filter(rc -> (rc.accessor.flags() & Flags.GENERATED_MEMBER) != 0)
2274 .map(rc -> {
2275 // we need to return the field not the record component
2276 JCVariableDecl field = fields.stream().filter(f -> f.name == rc.name).findAny().get();
2277 make_at(tree.pos());
2278 return make.MethodDef(rc.accessor, make.Block(0,
2279 List.of(make.Return(make.Ident(field)))));
2280 }).collect(List.collector());
2281 }
2282
2283 /** Translate an enum class. */
2284 private void visitEnumDef(JCClassDecl tree) {
2285 make_at(tree.pos());
2286
2287 // add the supertype, if needed
2288 if (tree.extending == null)
2289 tree.extending = make.Type(types.supertype(tree.type));
2290
2291 // classOfType adds a cache field to tree.defs
2292 JCExpression e_class = classOfType(tree.sym.type, tree.pos()).
2293 setType(types.erasure(syms.classType));
2294
2295 // process each enumeration constant, adding implicit constructor parameters
2296 int nextOrdinal = 0;
2297 ListBuffer<JCExpression> values = new ListBuffer<>();
2298 ListBuffer<JCTree> enumDefs = new ListBuffer<>();
2299 ListBuffer<JCTree> otherDefs = new ListBuffer<>();
2300 for (List<JCTree> defs = tree.defs;
2301 defs.nonEmpty();
2302 defs=defs.tail) {
2303 if (defs.head.hasTag(VARDEF) && (((JCVariableDecl) defs.head).mods.flags & ENUM) != 0) {
2304 JCVariableDecl var = (JCVariableDecl)defs.head;
2305 visitEnumConstantDef(var, nextOrdinal++);
2306 values.append(make.QualIdent(var.sym));
2307 enumDefs.append(var);
2308 } else {
2309 otherDefs.append(defs.head);
2310 }
2311 }
2312
2313 // synthetic private static T[] $values() { return new T[] { a, b, c }; }
2314 // synthetic private static final T[] $VALUES = $values();
2315 Name valuesName = syntheticName(tree, "VALUES");
2316 Type arrayType = new ArrayType(types.erasure(tree.type), syms.arrayClass);
2317 VarSymbol valuesVar = new VarSymbol(PRIVATE|FINAL|STATIC|SYNTHETIC,
2318 valuesName,
2319 arrayType,
2320 tree.type.tsym);
2321 JCNewArray newArray = make.NewArray(make.Type(types.erasure(tree.type)),
2322 List.nil(),
2323 values.toList());
2324 newArray.type = arrayType;
2325
2326 MethodSymbol valuesMethod = new MethodSymbol(PRIVATE|STATIC|SYNTHETIC,
2327 syntheticName(tree, "values"),
2328 new MethodType(List.nil(), arrayType, List.nil(), tree.type.tsym),
2329 tree.type.tsym);
2330 enumDefs.append(make.MethodDef(valuesMethod, make.Block(0, List.of(make.Return(newArray)))));
2331 tree.sym.members().enter(valuesMethod);
2332
2333 enumDefs.append(make.VarDef(valuesVar, make.App(make.QualIdent(valuesMethod))));
2334 tree.sym.members().enter(valuesVar);
2335
2336 MethodSymbol valuesSym = lookupMethod(tree.pos(), names.values,
2337 tree.type, List.nil());
2338 List<JCStatement> valuesBody;
2339 if (useClone()) {
2340 // return (T[]) $VALUES.clone();
2341 JCTypeCast valuesResult =
2342 make.TypeCast(valuesSym.type.getReturnType(),
2343 make.App(make.Select(make.Ident(valuesVar),
2344 syms.arrayCloneMethod)));
2345 valuesBody = List.of(make.Return(valuesResult));
2346 } else {
2347 // template: T[] $result = new T[$values.length];
2348 Name resultName = syntheticName(tree, "result");
2349 VarSymbol resultVar = new VarSymbol(FINAL|SYNTHETIC,
2350 resultName,
2351 arrayType,
2352 valuesSym);
2353 JCNewArray resultArray = make.NewArray(make.Type(types.erasure(tree.type)),
2354 List.of(make.Select(make.Ident(valuesVar), syms.lengthVar)),
2355 null);
2356 resultArray.type = arrayType;
2357 JCVariableDecl decl = make.VarDef(resultVar, resultArray);
2358
2359 // template: System.arraycopy($VALUES, 0, $result, 0, $VALUES.length);
2360 if (systemArraycopyMethod == null) {
2361 systemArraycopyMethod =
2362 new MethodSymbol(PUBLIC | STATIC,
2363 names.fromString("arraycopy"),
2364 new MethodType(List.of(syms.objectType,
2365 syms.intType,
2366 syms.objectType,
2367 syms.intType,
2368 syms.intType),
2369 syms.voidType,
2370 List.nil(),
2371 syms.methodClass),
2372 syms.systemType.tsym);
2373 }
2374 JCStatement copy =
2375 make.Exec(make.App(make.Select(make.Ident(syms.systemType.tsym),
2376 systemArraycopyMethod),
2377 List.of(make.Ident(valuesVar), make.Literal(0),
2378 make.Ident(resultVar), make.Literal(0),
2379 make.Select(make.Ident(valuesVar), syms.lengthVar))));
2380
2381 // template: return $result;
2382 JCStatement ret = make.Return(make.Ident(resultVar));
2383 valuesBody = List.of(decl, copy, ret);
2384 }
2385
2386 JCMethodDecl valuesDef =
2387 make.MethodDef(valuesSym, make.Block(0, valuesBody));
2388
2389 enumDefs.append(valuesDef);
2390
2391 if (debugLower)
2392 System.err.println(tree.sym + ".valuesDef = " + valuesDef);
2393
2394 /** The template for the following code is:
2395 *
2396 * public static E valueOf(String name) {
2397 * return (E)Enum.valueOf(E.class, name);
2398 * }
2399 *
2400 * where E is tree.sym
2401 */
2402 MethodSymbol valueOfSym = lookupMethod(tree.pos(),
2403 names.valueOf,
2404 tree.sym.type,
2405 List.of(syms.stringType));
2406 Assert.check((valueOfSym.flags() & STATIC) != 0);
2407 VarSymbol nameArgSym = valueOfSym.params.head;
2408 JCIdent nameVal = make.Ident(nameArgSym);
2409 JCStatement enum_ValueOf =
2410 make.Return(make.TypeCast(tree.sym.type,
2411 makeCall(make.Ident(syms.enumSym),
2412 names.valueOf,
2413 List.of(e_class, nameVal))));
2414 JCMethodDecl valueOf = make.MethodDef(valueOfSym,
2415 make.Block(0, List.of(enum_ValueOf)));
2416 nameVal.sym = valueOf.params.head.sym;
2417 if (debugLower)
2418 System.err.println(tree.sym + ".valueOf = " + valueOf);
2419 enumDefs.append(valueOf);
2420
2421 enumDefs.appendList(otherDefs.toList());
2422 tree.defs = enumDefs.toList();
2423 }
2424 // where
2425 private MethodSymbol systemArraycopyMethod;
2426 private boolean useClone() {
2427 try {
2428 return syms.objectType.tsym.members().findFirst(names.clone) != null;
2429 }
2430 catch (CompletionFailure e) {
2431 return false;
2432 }
2433 }
2434
2435 private Name syntheticName(JCClassDecl tree, String baseName) {
2436 Name valuesName = names.fromString(target.syntheticNameChar() + baseName);
2437 while (tree.sym.members().findFirst(valuesName) != null) // avoid name clash
2438 valuesName = names.fromString(valuesName + "" + target.syntheticNameChar());
2439 return valuesName;
2440 }
2441
2442 /** Translate an enumeration constant and its initializer. */
2443 private void visitEnumConstantDef(JCVariableDecl var, int ordinal) {
2444 JCNewClass varDef = (JCNewClass)var.init;
2445 varDef.args = varDef.args.
2446 prepend(makeLit(syms.intType, ordinal)).
2447 prepend(makeLit(syms.stringType, var.name.toString()));
2448 }
2449
2450 private List<VarSymbol> recordVars(Type t) {
2451 List<VarSymbol> vars = List.nil();
2452 while (!t.hasTag(NONE)) {
2453 if (t.hasTag(CLASS)) {
2454 for (Symbol s : t.tsym.members().getSymbols(s -> s.kind == VAR && (s.flags() & RECORD) != 0)) {
2455 vars = vars.prepend((VarSymbol)s);
2456 }
2457 }
2458 t = types.supertype(t);
2459 }
2460 return vars;
2461 }
2462
2463 /** Translate a record. */
2464 private void visitRecordDef(JCClassDecl tree) {
2465 make_at(tree.pos());
2466 List<VarSymbol> vars = recordVars(tree.type);
2467 MethodHandleSymbol[] getterMethHandles = new MethodHandleSymbol[vars.size()];
2468 int index = 0;
2469 for (VarSymbol var : vars) {
2470 if (var.owner != tree.sym) {
2471 var = new VarSymbol(var.flags_field, var.name, var.type, tree.sym);
2472 }
2473 getterMethHandles[index] = var.asMethodHandle(true);
2474 index++;
2475 }
2476
2477 tree.defs = tree.defs.appendList(generateMandatedAccessors(tree));
2478 tree.defs = tree.defs.appendList(List.of(
2479 generateRecordMethod(tree, names.toString, vars, getterMethHandles),
2480 generateRecordMethod(tree, names.hashCode, vars, getterMethHandles),
2481 generateRecordMethod(tree, names.equals, vars, getterMethHandles)
2482 ));
2483 }
2484
2485 JCTree generateRecordMethod(JCClassDecl tree, Name name, List<VarSymbol> vars, MethodHandleSymbol[] getterMethHandles) {
2486 make_at(tree.pos());
2487 boolean isEquals = name == names.equals;
2488 MethodSymbol msym = lookupMethod(tree.pos(),
2489 name,
2490 tree.sym.type,
2491 isEquals ? List.of(syms.objectType) : List.nil());
2492 // compiler generated methods have the record flag set, user defined ones dont
2493 if ((msym.flags() & RECORD) != 0) {
2494 /* class java.lang.runtime.ObjectMethods provides a common bootstrap that provides a customized implementation
2495 * for methods: toString, hashCode and equals. Here we just need to generate and indy call to:
2496 * java.lang.runtime.ObjectMethods::bootstrap and provide: the record class, the record component names and
2497 * the accessors.
2498 */
2499 Name bootstrapName = names.bootstrap;
2500 LoadableConstant[] staticArgsValues = new LoadableConstant[2 + getterMethHandles.length];
2501 staticArgsValues[0] = (ClassType)tree.sym.type;
2502 String concatNames = vars.stream()
2503 .map(v -> v.name)
2504 .collect(Collectors.joining(";", "", ""));
2505 staticArgsValues[1] = LoadableConstant.String(concatNames);
2506 int index = 2;
2507 for (MethodHandleSymbol mho : getterMethHandles) {
2508 staticArgsValues[index] = mho;
2509 index++;
2510 }
2511
2512 List<Type> staticArgTypes = List.of(syms.classType,
2513 syms.stringType,
2514 new ArrayType(syms.methodHandleType, syms.arrayClass));
2515
2516 JCFieldAccess qualifier = makeIndyQualifier(syms.objectMethodsType, tree, msym,
2517 List.of(syms.methodHandleLookupType,
2518 syms.stringType,
2519 syms.typeDescriptorType).appendList(staticArgTypes),
2520 staticArgsValues, bootstrapName, name, false);
2521
2522 VarSymbol _this = new VarSymbol(SYNTHETIC, names._this, tree.sym.type, tree.sym);
2523
2524 JCMethodInvocation proxyCall;
2525 if (!isEquals) {
2526 proxyCall = make.Apply(List.nil(), qualifier, List.of(make.Ident(_this)));
2527 } else {
2528 VarSymbol o = msym.params.head;
2529 o.adr = 0;
2530 proxyCall = make.Apply(List.nil(), qualifier, List.of(make.Ident(_this), make.Ident(o)));
2531 }
2532 proxyCall.type = qualifier.type;
2533 return make.MethodDef(msym, make.Block(0, List.of(make.Return(proxyCall))));
2534 } else {
2535 return make.Block(SYNTHETIC, List.nil());
2536 }
2537 }
2538
2539 private String argsTypeSig(List<Type> typeList) {
2540 LowerSignatureGenerator sg = new LowerSignatureGenerator();
2541 sg.assembleSig(typeList);
2542 return sg.toString();
2543 }
2544
2545 /**
2546 * Signature Generation
2547 */
2548 private class LowerSignatureGenerator extends Types.SignatureGenerator {
2549
2550 /**
2551 * An output buffer for type signatures.
2552 */
2553 StringBuilder sb = new StringBuilder();
2554
2555 LowerSignatureGenerator() {
2556 types.super();
2557 }
2558
2559 @Override
2560 protected void append(char ch) {
2561 sb.append(ch);
2562 }
2563
2564 @Override
2565 protected void append(byte[] ba) {
2566 sb.append(new String(ba));
2567 }
2568
2569 @Override
2570 protected void append(Name name) {
2571 sb.append(name.toString());
2572 }
2573
2574 @Override
2575 public String toString() {
2576 return sb.toString();
2577 }
2578 }
2579
2580 /**
2581 * Creates an indy qualifier, helpful to be part of an indy invocation
2582 * @param site the site
2583 * @param tree a class declaration tree
2584 * @param msym the method symbol
2585 * @param staticArgTypes the static argument types
2586 * @param staticArgValues the static argument values
2587 * @param bootstrapName the bootstrap name to look for
2588 * @param argName normally bootstraps receives a method name as second argument, if you want that name
2589 * to be different to that of the bootstrap name pass a different name here
2590 * @param isStatic is it static or not
2591 * @return a field access tree
2592 */
2593 JCFieldAccess makeIndyQualifier(
2594 Type site,
2595 JCClassDecl tree,
2596 MethodSymbol msym,
2597 List<Type> staticArgTypes,
2598 LoadableConstant[] staticArgValues,
2599 Name bootstrapName,
2600 Name argName,
2601 boolean isStatic) {
2602 MethodSymbol bsm = rs.resolveInternalMethod(tree.pos(), attrEnv, site,
2603 bootstrapName, staticArgTypes, List.nil());
2604
2605 MethodType indyType = msym.type.asMethodType();
2606 indyType = new MethodType(
2607 isStatic ? List.nil() : indyType.argtypes.prepend(tree.sym.type),
2608 indyType.restype,
2609 indyType.thrown,
2610 syms.methodClass
2611 );
2612 DynamicMethodSymbol dynSym = new DynamicMethodSymbol(argName,
2613 syms.noSymbol,
2614 bsm.asHandle(),
2615 indyType,
2616 staticArgValues);
2617 JCFieldAccess qualifier = make.Select(make.QualIdent(site.tsym), argName);
2618 qualifier.sym = dynSym;
2619 qualifier.type = msym.type.asMethodType().restype;
2620 return qualifier;
2621 }
2622
2623 public void visitMethodDef(JCMethodDecl tree) {
2624 if (tree.name == names.init && (currentClass.flags_field&ENUM) != 0) {
2625 // Add "String $enum$name, int $enum$ordinal" to the beginning of the
2626 // argument list for each constructor of an enum.
2627 JCVariableDecl nameParam = make_at(tree.pos()).
2628 Param(names.fromString(target.syntheticNameChar() +
2629 "enum" + target.syntheticNameChar() + "name"),
2630 syms.stringType, tree.sym);
2631 nameParam.mods.flags |= SYNTHETIC; nameParam.sym.flags_field |= SYNTHETIC;
2632 JCVariableDecl ordParam = make.
2633 Param(names.fromString(target.syntheticNameChar() +
2634 "enum" + target.syntheticNameChar() +
2635 "ordinal"),
2636 syms.intType, tree.sym);
2637 ordParam.mods.flags |= SYNTHETIC; ordParam.sym.flags_field |= SYNTHETIC;
2638
2639 MethodSymbol m = tree.sym;
2640 tree.params = tree.params.prepend(ordParam).prepend(nameParam);
2641
2642 m.extraParams = m.extraParams.prepend(ordParam.sym);
2643 m.extraParams = m.extraParams.prepend(nameParam.sym);
2644 Type olderasure = m.erasure(types);
2645 m.erasure_field = new MethodType(
2646 olderasure.getParameterTypes().prepend(syms.intType).prepend(syms.stringType),
2647 olderasure.getReturnType(),
2648 olderasure.getThrownTypes(),
2649 syms.methodClass);
2650 }
2651
2652 Type prevRestype = currentRestype;
2653 JCMethodDecl prevMethodDef = currentMethodDef;
2654 MethodSymbol prevMethodSym = currentMethodSym;
2655 int prevVariableIndex = variableIndex;
2656 try {
2657 currentRestype = types.erasure(tree.type.getReturnType());
2658 currentMethodDef = tree;
2659 currentMethodSym = tree.sym;
2660 variableIndex = 0;
2661 visitMethodDefInternal(tree);
2662 } finally {
2663 currentRestype = prevRestype;
2664 currentMethodDef = prevMethodDef;
2665 currentMethodSym = prevMethodSym;
2666 variableIndex = prevVariableIndex;
2667 }
2668 }
2669
2670 private void visitMethodDefInternal(JCMethodDecl tree) {
2671 if (tree.name == names.init &&
2672 !currentClass.isStatic() &&
2673 (currentClass.isInner() || currentClass.isDirectlyOrIndirectlyLocal())) {
2674 // We are seeing a constructor of an inner class.
2675 MethodSymbol m = tree.sym;
2676
2677 // Push a new proxy scope for constructor parameters.
2678 // and create definitions for any this$n and proxy parameters.
2679 Map<Symbol, Symbol> prevProxies = proxies;
2680 proxies = new HashMap<>(proxies);
2681 List<VarSymbol> prevOuterThisStack = outerThisStack;
2682 List<VarSymbol> fvs = freevars(currentClass);
2683 JCVariableDecl otdef = null;
2684 if (currentClass.hasOuterInstance())
2685 otdef = outerThisDef(tree.pos, m);
2686 List<JCVariableDecl> fvdefs = freevarDefs(tree.pos, fvs, m, PARAMETER);
2687
2688 // Recursively translate result type, parameters and thrown list.
2689 tree.restype = translate(tree.restype);
2690 tree.params = translateVarDefs(tree.params);
2691 tree.thrown = translate(tree.thrown);
2692
2693 // when compiling stubs, don't process body
2694 if (tree.body == null) {
2695 result = tree;
2696 return;
2697 }
2698
2699 // Add this$n (if needed) in front of and free variables behind
2700 // constructor parameter list.
2701 tree.params = tree.params.appendList(fvdefs);
2702 if (currentClass.hasOuterInstance()) {
2703 tree.params = tree.params.prepend(otdef);
2704 }
2705
2706 // Determine whether this constructor has a super() invocation
2707 boolean invokesSuper = TreeInfo.hasConstructorCall(tree, names._super);
2708
2709 // Create initializers for this$n and proxies
2710 ListBuffer<JCStatement> added = new ListBuffer<>();
2711 if (fvs.nonEmpty()) {
2712 List<Type> addedargtypes = List.nil();
2713 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) {
2714 m.capturedLocals =
2715 m.capturedLocals.prepend((VarSymbol)
2716 (proxies.get(l.head)));
2717 if (invokesSuper) {
2718 added = added.prepend(
2719 initField(tree.body.pos, proxies.get(l.head), prevProxies.get(l.head)));
2720 }
2721 addedargtypes = addedargtypes.prepend(l.head.erasure(types));
2722 }
2723 Type olderasure = m.erasure(types);
2724 m.erasure_field = new MethodType(
2725 olderasure.getParameterTypes().appendList(addedargtypes),
2726 olderasure.getReturnType(),
2727 olderasure.getThrownTypes(),
2728 syms.methodClass);
2729 }
2730
2731 // Recursively translate existing local statements
2732 tree.body.stats = translate(tree.body.stats);
2733
2734 // Prepend initializers in front of super() call
2735 if (added.nonEmpty()) {
2736 List<JCStatement> initializers = added.toList();
2737 TreeInfo.mapSuperCalls(tree.body, supercall -> make.Block(0, initializers.append(supercall)));
2738 }
2739
2740 // pop local variables from proxy stack
2741 proxies = prevProxies;
2742
2743 outerThisStack = prevOuterThisStack;
2744 } else {
2745 super.visitMethodDef(tree);
2746 }
2747 if (tree.name == names.init && ((tree.sym.flags_field & Flags.COMPACT_RECORD_CONSTRUCTOR) != 0 ||
2748 (tree.sym.flags_field & (GENERATEDCONSTR | RECORD)) == (GENERATEDCONSTR | RECORD))) {
2749 // lets find out if there is any field waiting to be initialized
2750 ListBuffer<VarSymbol> fields = new ListBuffer<>();
2751 for (Symbol sym : currentClass.getEnclosedElements()) {
2752 if (sym.kind == Kinds.Kind.VAR && ((sym.flags() & RECORD) != 0))
2753 fields.append((VarSymbol) sym);
2754 }
2755 ListBuffer<JCStatement> initializers = new ListBuffer<>();
2756 for (VarSymbol field: fields) {
2757 if ((field.flags_field & Flags.UNINITIALIZED_FIELD) != 0) {
2758 VarSymbol param = tree.params.stream().filter(p -> p.name == field.name).findFirst().get().sym;
2759 make.at(tree.pos);
2760 initializers.add(make.Exec(
2761 make.Assign(
2762 make.Select(make.This(field.owner.erasure(types)), field),
2763 make.Ident(param)).setType(field.erasure(types))));
2764 field.flags_field &= ~Flags.UNINITIALIZED_FIELD;
2765 }
2766 }
2767 if (initializers.nonEmpty()) {
2768 if (tree.sym.owner.isValueClass()) {
2769 TreeInfo.mapSuperCalls(tree.body, supercall -> make.Block(0, initializers.toList().append(supercall)));
2770 } else {
2771 tree.body.stats = tree.body.stats.appendList(initializers);
2772 }
2773 }
2774 }
2775 result = tree;
2776 }
2777
2778 public void visitTypeCast(JCTypeCast tree) {
2779 tree.clazz = translate(tree.clazz);
2780 if (tree.type.isPrimitive() != tree.expr.type.isPrimitive())
2781 tree.expr = translate(tree.expr, tree.type);
2782 else
2783 tree.expr = translate(tree.expr);
2784 result = tree;
2785 }
2786
2787 /**
2788 * All the exactness checks between primitive types that require a run-time
2789 * check are in {@code java.lang.runtime.ExactConversionsSupport}. Those methods
2790 * are in the form {@code ExactConversionsSupport.is<S>To<T>Exact} where both
2791 * {@code S} and {@code T} are primitive types and correspond to the runtime
2792 * action that will be executed to check whether a certain value (that is passed
2793 * as a parameter) can be converted to {@code T} without loss of information.
2794 *
2795 * Rewrite {@code instanceof if expr : Object} and Type is primitive type:
2796 *
2797 * {@snippet :
2798 * Object v = ...
2799 * if (v instanceof float)
2800 * =>
2801 * if (let tmp$123 = v; tmp$123 instanceof Float)
2802 * }
2803 *
2804 * Rewrite {@code instanceof if expr : wrapper reference type}
2805 *
2806 * {@snippet :
2807 * Integer v = ...
2808 * if (v instanceof float)
2809 * =>
2810 * if (let tmp$123 = v; tmp$123 != null && ExactConversionsSupport.intToFloatExact(tmp$123.intValue()))
2811 * }
2812 *
2813 * Rewrite {@code instanceof if expr : primitive}
2814 *
2815 * {@snippet :
2816 * int v = ...
2817 * if (v instanceof float)
2818 * =>
2819 * if (let tmp$123 = v; ExactConversionsSupport.intToFloatExact(tmp$123))
2820 * }
2821 *
2822 * More rewritings:
2823 * <ul>
2824 * <li>If the {@code instanceof} check is unconditionally exact rewrite to true.</li>
2825 * <li>If expression type is {@code Byte}, {@code Short}, {@code Integer}, ..., an
2826 * unboxing conversion followed by a widening primitive conversion.</li>
2827 * <li>If expression type is a supertype: {@code Number}, a narrowing reference
2828 * conversion followed by an unboxing conversion.</li>
2829 * </ul>
2830 */
2831 public void visitTypeTest(JCInstanceOf tree) {
2832 if (tree.expr.type.isPrimitive() || tree.pattern.type.isPrimitive()) {
2833 JCExpression exactnessCheck = null;
2834 JCExpression instanceOfExpr = translate(tree.expr);
2835
2836 // preserving the side effects of the value
2837 VarSymbol dollar_s = new VarSymbol(FINAL | SYNTHETIC,
2838 names.fromString("tmp" + variableIndex++ + this.target.syntheticNameChar()),
2839 types.erasure(tree.expr.type),
2840 currentMethodSym);
2841 JCStatement var = make.at(tree.pos())
2842 .VarDef(dollar_s, instanceOfExpr);
2843
2844 if (types.isUnconditionallyExact(tree.expr.type, tree.pattern.type)) {
2845 exactnessCheck = make.Literal(BOOLEAN, 1).setType(syms.booleanType.constType(1));
2846 }
2847 else if (tree.expr.type.isReference()) {
2848 JCExpression nullCheck =
2849 makeBinary(NE,
2850 make.Ident(dollar_s),
2851 makeNull());
2852
2853 if (types.isUnconditionallyExact(types.unboxedType(tree.expr.type), tree.pattern.type)) {
2854 exactnessCheck = nullCheck;
2855 } else if (types.unboxedType(tree.expr.type).isPrimitive()) {
2856 exactnessCheck =
2857 makeBinary(AND,
2858 nullCheck,
2859 getExactnessCheck(tree, boxIfNeeded(make.Ident(dollar_s), types.unboxedType(tree.expr.type))));
2860 } else {
2861 exactnessCheck =
2862 makeBinary(AND,
2863 nullCheck,
2864 make.at(tree.pos())
2865 .TypeTest(make.Ident(dollar_s), make.Type(types.boxedClass(tree.pattern.type).type))
2866 .setType(syms.booleanType));
2867 }
2868 }
2869 else if (tree.expr.type.isPrimitive()) {
2870 exactnessCheck = getExactnessCheck(tree, make.Ident(dollar_s));
2871 }
2872
2873 result = make.LetExpr(List.of(var), exactnessCheck)
2874 .setType(syms.booleanType);
2875 } else {
2876 tree.expr = translate(tree.expr);
2877 tree.pattern = translate(tree.pattern);
2878 result = tree;
2879 }
2880 }
2881
2882 // TypePairs should be in sync with the corresponding record in SwitchBootstraps
2883 record TypePairs(TypeSymbol from, TypeSymbol to) {
2884 public static TypePairs of(Symtab syms, Type from, Type to) {
2885 if (from == syms.byteType || from == syms.shortType || from == syms.charType) {
2886 from = syms.intType;
2887 }
2888 return new TypePairs(from, to);
2889 }
2890
2891 public TypePairs(Type from, Type to) {
2892 this(from.tsym, to.tsym);
2893 }
2894
2895 public static HashMap<TypePairs, String> initialize(Symtab syms) {
2896 HashMap<TypePairs, String> typePairToName = new HashMap<>();
2897 typePairToName.put(new TypePairs(syms.byteType, syms.charType), "isIntToCharExact"); // redirected
2898 typePairToName.put(new TypePairs(syms.shortType, syms.byteType), "isIntToByteExact"); // redirected
2899 typePairToName.put(new TypePairs(syms.shortType, syms.charType), "isIntToCharExact"); // redirected
2900 typePairToName.put(new TypePairs(syms.charType, syms.byteType), "isIntToByteExact"); // redirected
2901 typePairToName.put(new TypePairs(syms.charType, syms.shortType), "isIntToShortExact"); // redirected
2902 typePairToName.put(new TypePairs(syms.intType, syms.byteType), "isIntToByteExact");
2903 typePairToName.put(new TypePairs(syms.intType, syms.shortType), "isIntToShortExact");
2904 typePairToName.put(new TypePairs(syms.intType, syms.charType), "isIntToCharExact");
2905 typePairToName.put(new TypePairs(syms.intType, syms.floatType), "isIntToFloatExact");
2906 typePairToName.put(new TypePairs(syms.longType, syms.byteType), "isLongToByteExact");
2907 typePairToName.put(new TypePairs(syms.longType, syms.shortType), "isLongToShortExact");
2908 typePairToName.put(new TypePairs(syms.longType, syms.charType), "isLongToCharExact");
2909 typePairToName.put(new TypePairs(syms.longType, syms.intType), "isLongToIntExact");
2910 typePairToName.put(new TypePairs(syms.longType, syms.floatType), "isLongToFloatExact");
2911 typePairToName.put(new TypePairs(syms.longType, syms.doubleType), "isLongToDoubleExact");
2912 typePairToName.put(new TypePairs(syms.floatType, syms.byteType), "isFloatToByteExact");
2913 typePairToName.put(new TypePairs(syms.floatType, syms.shortType), "isFloatToShortExact");
2914 typePairToName.put(new TypePairs(syms.floatType, syms.charType), "isFloatToCharExact");
2915 typePairToName.put(new TypePairs(syms.floatType, syms.intType), "isFloatToIntExact");
2916 typePairToName.put(new TypePairs(syms.floatType, syms.longType), "isFloatToLongExact");
2917 typePairToName.put(new TypePairs(syms.doubleType, syms.byteType), "isDoubleToByteExact");
2918 typePairToName.put(new TypePairs(syms.doubleType, syms.shortType), "isDoubleToShortExact");
2919 typePairToName.put(new TypePairs(syms.doubleType, syms.charType), "isDoubleToCharExact");
2920 typePairToName.put(new TypePairs(syms.doubleType, syms.intType), "isDoubleToIntExact");
2921 typePairToName.put(new TypePairs(syms.doubleType, syms.longType), "isDoubleToLongExact");
2922 typePairToName.put(new TypePairs(syms.doubleType, syms.floatType), "isDoubleToFloatExact");
2923 return typePairToName;
2924 }
2925 }
2926
2927 private JCExpression getExactnessCheck(JCInstanceOf tree, JCExpression argument) {
2928 TypePairs pair = TypePairs.of(syms, types.unboxedTypeOrType(tree.expr.type), tree.pattern.type);
2929
2930 Name exactnessFunction = names.fromString(typePairToName.get(pair));
2931
2932 // Resolve the exactness method
2933 Symbol ecsym = lookupMethod(tree.pos(),
2934 exactnessFunction,
2935 syms.exactConversionsSupportType,
2936 List.of(pair.from.type));
2937
2938 // Generate the method call ExactnessChecks.<exactness method>(<argument>);
2939 JCFieldAccess select = make.Select(
2940 make.QualIdent(syms.exactConversionsSupportType.tsym),
2941 exactnessFunction);
2942 select.sym = ecsym;
2943 select.setType(syms.booleanType);
2944
2945 JCExpression exactnessCheck = make.Apply(List.nil(),
2946 select,
2947 List.of(argument));
2948 exactnessCheck.setType(syms.booleanType);
2949 return exactnessCheck;
2950 }
2951
2952 public void visitNewClass(JCNewClass tree) {
2953 ClassSymbol c = (ClassSymbol)tree.constructor.owner;
2954
2955 // Box arguments, if necessary
2956 boolean isEnum = (tree.constructor.owner.flags() & ENUM) != 0;
2957 List<Type> argTypes = tree.constructor.type.getParameterTypes();
2958 if (isEnum) argTypes = argTypes.prepend(syms.intType).prepend(syms.stringType);
2959 tree.args = boxArgs(argTypes, tree.args, tree.varargsElement);
2960 tree.varargsElement = null;
2961
2962 // If created class is local, add free variables after
2963 // explicit constructor arguments.
2964 if (c.isDirectlyOrIndirectlyLocal() && !c.isStatic()) {
2965 tree.args = tree.args.appendList(loadFreevars(tree.pos(), freevars(c)));
2966 }
2967
2968 // If an access constructor is used, append null as a last argument.
2969 Symbol constructor = accessConstructor(tree.pos(), tree.constructor);
2970 if (constructor != tree.constructor) {
2971 tree.args = tree.args.append(makeNull());
2972 tree.constructor = constructor;
2973 }
2974
2975 // If created class has an outer instance, and new is qualified, pass
2976 // qualifier as first argument. If new is not qualified, pass the
2977 // correct outer instance as first argument.
2978 if (c.hasOuterInstance()) {
2979 JCExpression thisArg;
2980 if (tree.encl != null) {
2981 thisArg = attr.makeNullCheck(translate(tree.encl));
2982 thisArg.type = tree.encl.type;
2983 } else if (c.isDirectlyOrIndirectlyLocal()) {
2984 // local class
2985 thisArg = makeThis(tree.pos(), c.innermostAccessibleEnclosingClass());
2986 } else {
2987 // nested class
2988 thisArg = makeOwnerThis(tree.pos(), c, false);
2989 if (currentMethodSym != null &&
2990 ((currentMethodSym.flags_field & (STATIC | BLOCK)) == BLOCK) &&
2991 currentMethodSym.owner.isValueClass()) {
2992 // instance initializer in a value class
2993 Set<JCExpression> outerThisSet = initializerOuterThis.get(currentClass);
2994 if (outerThisSet == null) {
2995 outerThisSet = new HashSet<>();
2996 }
2997 outerThisSet.add(thisArg);
2998 initializerOuterThis.put(currentClass, outerThisSet);
2999 }
3000 }
3001 tree.args = tree.args.prepend(thisArg);
3002 }
3003 tree.encl = null;
3004
3005 // If we have an anonymous class, create its flat version, rather
3006 // than the class or interface following new.
3007 if (tree.def != null) {
3008 translate(tree.def);
3009
3010 tree.clazz = access(make_at(tree.clazz.pos()).Ident(tree.def.sym));
3011 tree.def = null;
3012 } else {
3013 tree.clazz = access(c, tree.clazz, enclOp, false);
3014 }
3015 result = tree;
3016 }
3017
3018 // Simplify conditionals with known constant controlling expressions.
3019 // This allows us to avoid generating supporting declarations for
3020 // the dead code, which will not be eliminated during code generation.
3021 // Note that Flow.isFalse and Flow.isTrue only return true
3022 // for constant expressions in the sense of JLS 15.27, which
3023 // are guaranteed to have no side-effects. More aggressive
3024 // constant propagation would require that we take care to
3025 // preserve possible side-effects in the condition expression.
3026
3027 // One common case is equality expressions involving a constant and null.
3028 // Since null is not a constant expression (because null cannot be
3029 // represented in the constant pool), equality checks involving null are
3030 // not captured by Flow.isTrue/isFalse.
3031 // Equality checks involving a constant and null, e.g.
3032 // "" == null
3033 // are safe to simplify as no side-effects can occur.
3034
3035 private boolean isTrue(JCTree exp) {
3036 if (exp.type.isTrue())
3037 return true;
3038 Boolean b = expValue(exp);
3039 return b == null ? false : b;
3040 }
3041 private boolean isFalse(JCTree exp) {
3042 if (exp.type.isFalse())
3043 return true;
3044 Boolean b = expValue(exp);
3045 return b == null ? false : !b;
3046 }
3047 /* look for (in)equality relations involving null.
3048 * return true - if expression is always true
3049 * false - if expression is always false
3050 * null - if expression cannot be eliminated
3051 */
3052 private Boolean expValue(JCTree exp) {
3053 while (exp.hasTag(PARENS))
3054 exp = ((JCParens)exp).expr;
3055
3056 boolean eq;
3057 switch (exp.getTag()) {
3058 case EQ: eq = true; break;
3059 case NE: eq = false; break;
3060 default:
3061 return null;
3062 }
3063
3064 // we have a JCBinary(EQ|NE)
3065 // check if we have two literals (constants or null)
3066 JCBinary b = (JCBinary)exp;
3067 if (b.lhs.type.hasTag(BOT)) return expValueIsNull(eq, b.rhs);
3068 if (b.rhs.type.hasTag(BOT)) return expValueIsNull(eq, b.lhs);
3069 return null;
3070 }
3071 private Boolean expValueIsNull(boolean eq, JCTree t) {
3072 if (t.type.hasTag(BOT)) return Boolean.valueOf(eq);
3073 if (t.hasTag(LITERAL)) return Boolean.valueOf(!eq);
3074 return null;
3075 }
3076
3077 /** Visitor method for conditional expressions.
3078 */
3079 @Override
3080 public void visitConditional(JCConditional tree) {
3081 JCTree cond = tree.cond = translate(tree.cond, syms.booleanType);
3082 if (isTrue(cond) && noClassDefIn(tree.falsepart)) {
3083 result = convert(translate(tree.truepart, tree.type), tree.type);
3084 addPrunedInfo(cond);
3085 } else if (isFalse(cond) && noClassDefIn(tree.truepart)) {
3086 result = convert(translate(tree.falsepart, tree.type), tree.type);
3087 addPrunedInfo(cond);
3088 } else {
3089 // Condition is not a compile-time constant.
3090 tree.truepart = translate(tree.truepart, tree.type);
3091 tree.falsepart = translate(tree.falsepart, tree.type);
3092 result = tree;
3093 }
3094 }
3095 //where
3096 private JCExpression convert(JCExpression tree, Type pt) {
3097 if (tree.type == pt || tree.type.hasTag(BOT))
3098 return tree;
3099 JCExpression result = make_at(tree.pos()).TypeCast(make.Type(pt), tree);
3100 result.type = (tree.type.constValue() != null) ? cfolder.coerce(tree.type, pt)
3101 : pt;
3102 return result;
3103 }
3104
3105 /** Visitor method for if statements.
3106 */
3107 public void visitIf(JCIf tree) {
3108 JCTree cond = tree.cond = translate(tree.cond, syms.booleanType);
3109 if (isTrue(cond) && noClassDefIn(tree.elsepart)) {
3110 result = translate(tree.thenpart);
3111 addPrunedInfo(cond);
3112 } else if (isFalse(cond) && noClassDefIn(tree.thenpart)) {
3113 if (tree.elsepart != null) {
3114 result = translate(tree.elsepart);
3115 } else {
3116 result = make.Skip();
3117 }
3118 addPrunedInfo(cond);
3119 } else {
3120 // Condition is not a compile-time constant.
3121 tree.thenpart = translate(tree.thenpart);
3122 tree.elsepart = translate(tree.elsepart);
3123 result = tree;
3124 }
3125 }
3126
3127 /** Visitor method for assert statements. Translate them away.
3128 */
3129 public void visitAssert(JCAssert tree) {
3130 tree.cond = translate(tree.cond, syms.booleanType);
3131 if (!tree.cond.type.isTrue()) {
3132 JCExpression cond = assertFlagTest(tree.pos());
3133 List<JCExpression> exnArgs = (tree.detail == null) ?
3134 List.nil() : List.of(translate(tree.detail));
3135 if (!tree.cond.type.isFalse()) {
3136 cond = makeBinary
3137 (AND,
3138 cond,
3139 makeUnary(NOT, tree.cond));
3140 }
3141 result =
3142 make.If(cond,
3143 make_at(tree).
3144 Throw(makeNewClass(syms.assertionErrorType, exnArgs)),
3145 null);
3146 } else {
3147 result = make.Skip();
3148 }
3149 }
3150
3151 public void visitApply(JCMethodInvocation tree) {
3152 Symbol meth = TreeInfo.symbol(tree.meth);
3153 List<Type> argtypes = meth.type.getParameterTypes();
3154 if (meth.name == names.init && meth.owner == syms.enumSym)
3155 argtypes = argtypes.tail.tail;
3156 tree.args = boxArgs(argtypes, tree.args, tree.varargsElement);
3157 tree.varargsElement = null;
3158 Name methName = TreeInfo.name(tree.meth);
3159 if (meth.name==names.init) {
3160 // We are seeing a this(...) or super(...) constructor call.
3161 // If an access constructor is used, append null as a last argument.
3162 Symbol constructor = accessConstructor(tree.pos(), meth);
3163 if (constructor != meth) {
3164 tree.args = tree.args.append(makeNull());
3165 TreeInfo.setSymbol(tree.meth, constructor);
3166 }
3167
3168 // If we are calling a constructor of a local class, add
3169 // free variables after explicit constructor arguments.
3170 ClassSymbol c = (ClassSymbol)constructor.owner;
3171 if (c.isDirectlyOrIndirectlyLocal() && !c.isStatic()) {
3172 tree.args = tree.args.appendList(loadFreevars(tree.pos(), freevars(c)));
3173 }
3174
3175 // If we are calling a constructor of an enum class, pass
3176 // along the name and ordinal arguments
3177 if ((c.flags_field&ENUM) != 0 || c.getQualifiedName() == names.java_lang_Enum) {
3178 List<JCVariableDecl> params = currentMethodDef.params;
3179 if (currentMethodSym.owner.hasOuterInstance())
3180 params = params.tail; // drop this$n
3181 tree.args = tree.args
3182 .prepend(make_at(tree.pos()).Ident(params.tail.head.sym)) // ordinal
3183 .prepend(make.Ident(params.head.sym)); // name
3184 }
3185
3186 // If we are calling a constructor of a class with an outer
3187 // instance, and the call
3188 // is qualified, pass qualifier as first argument in front of
3189 // the explicit constructor arguments. If the call
3190 // is not qualified, pass the correct outer instance as
3191 // first argument. If we are a static class, there is no
3192 // such outer instance, so generate an error.
3193 if (c.hasOuterInstance()) {
3194 JCExpression thisArg;
3195 if (tree.meth.hasTag(SELECT)) {
3196 thisArg = attr.
3197 makeNullCheck(translate(((JCFieldAccess) tree.meth).selected));
3198 tree.meth = make.Ident(constructor);
3199 ((JCIdent) tree.meth).name = methName;
3200 } else if (c.isDirectlyOrIndirectlyLocal() || methName == names._this){
3201 // local class or this() call
3202 thisArg = makeThis(tree.meth.pos(), c.innermostAccessibleEnclosingClass());
3203 } else if (currentClass.isStatic()) {
3204 // super() call from static nested class - invalid
3205 log.error(tree.pos(),
3206 Errors.NoEnclInstanceOfTypeInScope(c.type.getEnclosingType().tsym));
3207 thisArg = make.Literal(BOT, null).setType(syms.botType);
3208 } else {
3209 // super() call of nested class - never pick 'this'
3210 thisArg = makeOwnerThisN(tree.meth.pos(), c, false);
3211 }
3212 tree.args = tree.args.prepend(thisArg);
3213 }
3214 } else {
3215 // We are seeing a normal method invocation; translate this as usual.
3216 tree.meth = translate(tree.meth);
3217
3218 // If the translated method itself is an Apply tree, we are
3219 // seeing an access method invocation. In this case, append
3220 // the method arguments to the arguments of the access method.
3221 if (tree.meth.hasTag(APPLY)) {
3222 JCMethodInvocation app = (JCMethodInvocation)tree.meth;
3223 app.args = tree.args.prependList(app.args);
3224 result = app;
3225 return;
3226 }
3227 }
3228 if (tree.args.stream().anyMatch(c -> c == null)) {
3229 throw new AssertionError("Whooops before: " + tree);
3230 }
3231 result = tree;
3232 }
3233
3234 List<JCExpression> boxArgs(List<Type> parameters, List<JCExpression> _args, Type varargsElement) {
3235 List<JCExpression> args = _args;
3236 if (parameters.isEmpty()) return args;
3237 boolean anyChanges = false;
3238 ListBuffer<JCExpression> result = new ListBuffer<>();
3239 while (parameters.tail.nonEmpty()) {
3240 JCExpression arg = translate(args.head, parameters.head);
3241 anyChanges |= (arg != args.head);
3242 result.append(arg);
3243 args = args.tail;
3244 parameters = parameters.tail;
3245 }
3246 Type parameter = parameters.head;
3247 if (varargsElement != null) {
3248 anyChanges = true;
3249 ListBuffer<JCExpression> elems = new ListBuffer<>();
3250 while (args.nonEmpty()) {
3251 JCExpression arg = translate(args.head, varargsElement);
3252 elems.append(arg);
3253 args = args.tail;
3254 }
3255 JCNewArray boxedArgs = make.NewArray(make.Type(varargsElement),
3256 List.nil(),
3257 elems.toList());
3258 boxedArgs.type = new ArrayType(varargsElement, syms.arrayClass);
3259 result.append(boxedArgs);
3260 } else {
3261 if (args.length() != 1) throw new AssertionError(args);
3262 JCExpression arg = translate(args.head, parameter);
3263 anyChanges |= (arg != args.head);
3264 result.append(arg);
3265 if (!anyChanges) return _args;
3266 }
3267 return result.toList();
3268 }
3269
3270 /** Expand a boxing or unboxing conversion if needed. */
3271 @SuppressWarnings("unchecked") // XXX unchecked
3272 <T extends JCExpression> T boxIfNeeded(T tree, Type type) {
3273 Assert.check(!type.hasTag(VOID));
3274 if (type.hasTag(NONE))
3275 return tree;
3276 boolean havePrimitive = tree.type.isPrimitive();
3277 if (havePrimitive == type.isPrimitive())
3278 return tree;
3279 if (havePrimitive) {
3280 Type unboxedTarget = types.unboxedType(type);
3281 if (!unboxedTarget.hasTag(NONE)) {
3282 if (!types.isSubtype(tree.type, unboxedTarget)) //e.g. Character c = 89;
3283 tree.type = unboxedTarget.constType(tree.type.constValue());
3284 return (T)boxPrimitive(tree, types.erasure(type));
3285 } else {
3286 tree = (T)boxPrimitive(tree);
3287 }
3288 } else {
3289 tree = (T)unbox(tree, type);
3290 }
3291 return tree;
3292 }
3293
3294 /** Box up a single primitive expression. */
3295 JCExpression boxPrimitive(JCExpression tree) {
3296 return boxPrimitive(tree, types.boxedClass(tree.type).type);
3297 }
3298
3299 /** Box up a single primitive expression. */
3300 JCExpression boxPrimitive(JCExpression tree, Type box) {
3301 make_at(tree.pos());
3302 Symbol valueOfSym = lookupMethod(tree.pos(),
3303 names.valueOf,
3304 box,
3305 List.<Type>nil()
3306 .prepend(tree.type));
3307 return make.App(make.QualIdent(valueOfSym), List.of(tree));
3308 }
3309
3310 /** Unbox an object to a primitive value. */
3311 JCExpression unbox(JCExpression tree, Type primitive) {
3312 Type unboxedType = types.unboxedType(tree.type);
3313 if (unboxedType.hasTag(NONE)) {
3314 unboxedType = primitive;
3315 if (!unboxedType.isPrimitive())
3316 throw new AssertionError(unboxedType);
3317 make_at(tree.pos());
3318 tree = make.TypeCast(types.boxedClass(unboxedType).type, tree);
3319 } else {
3320 // There must be a conversion from unboxedType to primitive.
3321 if (!types.isSubtype(unboxedType, primitive))
3322 throw new AssertionError(tree);
3323 }
3324 make_at(tree.pos());
3325 Symbol valueSym = lookupMethod(tree.pos(),
3326 unboxedType.tsym.name.append(names.Value), // x.intValue()
3327 tree.type,
3328 List.nil());
3329 return make.App(make.Select(tree, valueSym));
3330 }
3331
3332 /** Visitor method for parenthesized expressions.
3333 * If the subexpression has changed, omit the parens.
3334 */
3335 public void visitParens(JCParens tree) {
3336 JCTree expr = translate(tree.expr);
3337 result = ((expr == tree.expr) ? tree : expr);
3338 }
3339
3340 public void visitIndexed(JCArrayAccess tree) {
3341 tree.indexed = translate(tree.indexed);
3342 tree.index = translate(tree.index, syms.intType);
3343 result = tree;
3344 }
3345
3346 public void visitAssign(JCAssign tree) {
3347 tree.lhs = translate(tree.lhs, tree);
3348 tree.rhs = translate(tree.rhs, tree.lhs.type);
3349
3350 // If translated left hand side is an Apply, we are
3351 // seeing an access method invocation. In this case, append
3352 // right hand side as last argument of the access method.
3353 if (tree.lhs.hasTag(APPLY)) {
3354 JCMethodInvocation app = (JCMethodInvocation)tree.lhs;
3355 app.args = List.of(tree.rhs).prependList(app.args);
3356 result = app;
3357 } else {
3358 result = tree;
3359 }
3360 }
3361
3362 public void visitAssignop(final JCAssignOp tree) {
3363 final boolean boxingReq = !tree.lhs.type.isPrimitive() &&
3364 tree.operator.type.getReturnType().isPrimitive();
3365
3366 AssignopDependencyScanner depScanner = new AssignopDependencyScanner(tree);
3367 depScanner.scan(tree.rhs);
3368
3369 if (boxingReq || depScanner.dependencyFound) {
3370 // boxing required; need to rewrite as x = (unbox typeof x)(x op y);
3371 // or if x == (typeof x)z then z = (unbox typeof x)((typeof x)z op y)
3372 // (but without recomputing x)
3373 JCTree newTree = abstractLval(tree.lhs, lhs -> {
3374 Tag newTag = tree.getTag().noAssignOp();
3375 // Erasure (TransTypes) can change the type of
3376 // tree.lhs. However, we can still get the
3377 // unerased type of tree.lhs as it is stored
3378 // in tree.type in Attr.
3379 OperatorSymbol newOperator = operators.resolveBinary(tree,
3380 newTag,
3381 tree.type,
3382 tree.rhs.type);
3383 //Need to use the "lhs" at two places, once on the future left hand side
3384 //and once in the future binary operator. But further processing may change
3385 //the components of the tree in place (see visitSelect for e.g. <Class>.super.<ident>),
3386 //so cloning the tree to avoid interference between the uses:
3387 JCExpression expr = (JCExpression) lhs.clone();
3388 if (expr.type != tree.type)
3389 expr = make.TypeCast(tree.type, expr);
3390 JCBinary opResult = make.Binary(newTag, expr, tree.rhs);
3391 opResult.operator = newOperator;
3392 opResult.type = newOperator.type.getReturnType();
3393 JCExpression newRhs = boxingReq ?
3394 make.TypeCast(types.unboxedType(tree.type), opResult) :
3395 opResult;
3396 return make.Assign(lhs, newRhs).setType(tree.type);
3397 });
3398 result = translate(newTree);
3399 return;
3400 }
3401 tree.lhs = translate(tree.lhs, tree);
3402 tree.rhs = translate(tree.rhs, tree.operator.type.getParameterTypes().tail.head);
3403
3404 // If translated left hand side is an Apply, we are
3405 // seeing an access method invocation. In this case, append
3406 // right hand side as last argument of the access method.
3407 if (tree.lhs.hasTag(APPLY)) {
3408 JCMethodInvocation app = (JCMethodInvocation)tree.lhs;
3409 // if operation is a += on strings,
3410 // make sure to convert argument to string
3411 JCExpression rhs = tree.operator.opcode == string_add
3412 ? makeString(tree.rhs)
3413 : tree.rhs;
3414 app.args = List.of(rhs).prependList(app.args);
3415 result = app;
3416 } else {
3417 result = tree;
3418 }
3419 }
3420
3421 class AssignopDependencyScanner extends TreeScanner {
3422
3423 Symbol sym;
3424 boolean dependencyFound = false;
3425
3426 AssignopDependencyScanner(JCAssignOp tree) {
3427 this.sym = TreeInfo.symbol(tree.lhs);
3428 }
3429
3430 @Override
3431 public void scan(JCTree tree) {
3432 if (tree != null && sym != null) {
3433 tree.accept(this);
3434 }
3435 }
3436
3437 @Override
3438 public void visitAssignop(JCAssignOp tree) {
3439 if (TreeInfo.symbol(tree.lhs) == sym) {
3440 dependencyFound = true;
3441 return;
3442 }
3443 super.visitAssignop(tree);
3444 }
3445
3446 @Override
3447 public void visitUnary(JCUnary tree) {
3448 if (TreeInfo.symbol(tree.arg) == sym) {
3449 dependencyFound = true;
3450 return;
3451 }
3452 super.visitUnary(tree);
3453 }
3454 }
3455
3456 /** Lower a tree of the form e++ or e-- where e is an object type */
3457 JCExpression lowerBoxedPostop(final JCUnary tree) {
3458 // translate to tmp1=lval(e); tmp2=tmp1; tmp1 OP 1; tmp2
3459 // or
3460 // translate to tmp1=lval(e); tmp2=tmp1; (typeof tree)tmp1 OP 1; tmp2
3461 // where OP is += or -=
3462 final boolean cast = TreeInfo.skipParens(tree.arg).hasTag(TYPECAST);
3463 return abstractLval(tree.arg, tmp1 -> abstractRval(tmp1, tree.arg.type, tmp2 -> {
3464 Tag opcode = (tree.hasTag(POSTINC))
3465 ? PLUS_ASG : MINUS_ASG;
3466 //"tmp1" and "tmp2" may refer to the same instance
3467 //(for e.g. <Class>.super.<ident>). But further processing may
3468 //change the components of the tree in place (see visitSelect),
3469 //so cloning the tree to avoid interference between the two uses:
3470 JCExpression lhs = (JCExpression)tmp1.clone();
3471 lhs = cast
3472 ? make.TypeCast(tree.arg.type, lhs)
3473 : lhs;
3474 JCExpression update = makeAssignop(opcode,
3475 lhs,
3476 make.Literal(1));
3477 return makeComma(update, tmp2);
3478 }));
3479 }
3480
3481 public void visitUnary(JCUnary tree) {
3482 boolean isUpdateOperator = tree.getTag().isIncOrDecUnaryOp();
3483 if (isUpdateOperator && !tree.arg.type.isPrimitive()) {
3484 switch(tree.getTag()) {
3485 case PREINC: // ++ e
3486 // translate to e += 1
3487 case PREDEC: // -- e
3488 // translate to e -= 1
3489 {
3490 JCTree.Tag opcode = (tree.hasTag(PREINC))
3491 ? PLUS_ASG : MINUS_ASG;
3492 JCAssignOp newTree = makeAssignop(opcode,
3493 tree.arg,
3494 make.Literal(1));
3495 result = translate(newTree, tree.type);
3496 return;
3497 }
3498 case POSTINC: // e ++
3499 case POSTDEC: // e --
3500 {
3501 result = translate(lowerBoxedPostop(tree), tree.type);
3502 return;
3503 }
3504 }
3505 throw new AssertionError(tree);
3506 }
3507
3508 tree.arg = boxIfNeeded(translate(tree.arg, tree), tree.type);
3509
3510 if (tree.hasTag(NOT) && tree.arg.type.constValue() != null) {
3511 tree.type = cfolder.fold1(bool_not, tree.arg.type);
3512 }
3513
3514 // If translated left hand side is an Apply, we are
3515 // seeing an access method invocation. In this case, return
3516 // that access method invocation as result.
3517 if (isUpdateOperator && tree.arg.hasTag(APPLY)) {
3518 result = tree.arg;
3519 } else {
3520 result = tree;
3521 }
3522 }
3523
3524 public void visitBinary(JCBinary tree) {
3525 List<Type> formals = tree.operator.type.getParameterTypes();
3526 JCTree lhs = tree.lhs = translate(tree.lhs, formals.head);
3527 switch (tree.getTag()) {
3528 case OR:
3529 if (isTrue(lhs)) {
3530 result = lhs;
3531 return;
3532 }
3533 if (isFalse(lhs)) {
3534 result = translate(tree.rhs, formals.tail.head);
3535 return;
3536 }
3537 break;
3538 case AND:
3539 if (isFalse(lhs)) {
3540 result = lhs;
3541 return;
3542 }
3543 if (isTrue(lhs)) {
3544 result = translate(tree.rhs, formals.tail.head);
3545 return;
3546 }
3547 break;
3548 }
3549 tree.rhs = translate(tree.rhs, formals.tail.head);
3550 result = tree;
3551 }
3552
3553 public void visitIdent(JCIdent tree) {
3554 result = access(tree.sym, tree, enclOp, false);
3555 }
3556
3557 /** Translate away the foreach loop. */
3558 public void visitForeachLoop(JCEnhancedForLoop tree) {
3559 if (types.elemtype(tree.expr.type) == null)
3560 visitIterableForeachLoop(tree);
3561 else
3562 visitArrayForeachLoop(tree);
3563 }
3564 // where
3565 /**
3566 * A statement of the form
3567 *
3568 * <pre>
3569 * for ( T v : arrayexpr ) stmt;
3570 * </pre>
3571 *
3572 * (where arrayexpr is of an array type) gets translated to
3573 *
3574 * <pre>{@code
3575 * for ( { arraytype #arr = arrayexpr;
3576 * int #len = array.length;
3577 * int #i = 0; };
3578 * #i < #len; i$++ ) {
3579 * T v = arr$[#i];
3580 * stmt;
3581 * }
3582 * }</pre>
3583 *
3584 * where #arr, #len, and #i are freshly named synthetic local variables.
3585 */
3586 private void visitArrayForeachLoop(JCEnhancedForLoop tree) {
3587 make_at(tree.expr.pos());
3588 VarSymbol arraycache = new VarSymbol(SYNTHETIC,
3589 names.fromString("arr" + target.syntheticNameChar()),
3590 tree.expr.type,
3591 currentMethodSym);
3592 JCStatement arraycachedef = make.VarDef(arraycache, tree.expr);
3593 VarSymbol lencache = new VarSymbol(SYNTHETIC,
3594 names.fromString("len" + target.syntheticNameChar()),
3595 syms.intType,
3596 currentMethodSym);
3597 JCStatement lencachedef = make.
3598 VarDef(lencache, make.Select(make.Ident(arraycache), syms.lengthVar));
3599 VarSymbol index = new VarSymbol(SYNTHETIC,
3600 names.fromString("i" + target.syntheticNameChar()),
3601 syms.intType,
3602 currentMethodSym);
3603
3604 JCVariableDecl indexdef = make.VarDef(index, make.Literal(INT, 0));
3605 indexdef.init.type = indexdef.type = syms.intType.constType(0);
3606
3607 List<JCStatement> loopinit = List.of(arraycachedef, lencachedef, indexdef);
3608 JCBinary cond = makeBinary(LT, make.Ident(index), make.Ident(lencache));
3609
3610 JCExpressionStatement step = make.Exec(makeUnary(PREINC, make.Ident(index)));
3611
3612 Type elemtype = types.elemtype(tree.expr.type);
3613 JCExpression loopvarinit = make.Indexed(make.Ident(arraycache),
3614 make.Ident(index)).setType(elemtype);
3615 JCVariableDecl loopvardef = (JCVariableDecl)make.VarDef(tree.var.mods,
3616 tree.var.name,
3617 tree.var.vartype,
3618 loopvarinit).setType(tree.var.type);
3619 loopvardef.sym = tree.var.sym;
3620 JCBlock body = make.
3621 Block(0, List.of(loopvardef, tree.body));
3622
3623 result = translate(make.
3624 ForLoop(loopinit,
3625 cond,
3626 List.of(step),
3627 body));
3628 patchTargets(body, tree, result);
3629 }
3630 /** Patch up break and continue targets. */
3631 private void patchTargets(JCTree body, final JCTree src, final JCTree dest) {
3632 class Patcher extends TreeScanner {
3633 public void visitBreak(JCBreak tree) {
3634 if (tree.target == src)
3635 tree.target = dest;
3636 }
3637 public void visitYield(JCYield tree) {
3638 if (tree.target == src)
3639 tree.target = dest;
3640 scan(tree.value);
3641 }
3642 public void visitContinue(JCContinue tree) {
3643 if (tree.target == src)
3644 tree.target = dest;
3645 }
3646 public void visitClassDef(JCClassDecl tree) {}
3647 }
3648 new Patcher().scan(body);
3649 }
3650 /**
3651 * A statement of the form
3652 *
3653 * <pre>
3654 * for ( T v : coll ) stmt ;
3655 * </pre>
3656 *
3657 * (where coll implements {@code Iterable<? extends T>}) gets translated to
3658 *
3659 * <pre>{@code
3660 * for ( Iterator<? extends T> #i = coll.iterator(); #i.hasNext(); ) {
3661 * T v = (T) #i.next();
3662 * stmt;
3663 * }
3664 * }</pre>
3665 *
3666 * where #i is a freshly named synthetic local variable.
3667 */
3668 private void visitIterableForeachLoop(JCEnhancedForLoop tree) {
3669 make_at(tree.expr.pos());
3670 Type iteratorTarget = syms.objectType;
3671 Type iterableType = types.asSuper(types.cvarUpperBound(tree.expr.type),
3672 syms.iterableType.tsym);
3673 if (iterableType.getTypeArguments().nonEmpty())
3674 iteratorTarget = types.erasure(iterableType.getTypeArguments().head);
3675 tree.expr.type = types.erasure(types.skipTypeVars(tree.expr.type, false));
3676 tree.expr = transTypes.coerce(attrEnv, tree.expr, types.erasure(iterableType));
3677 Symbol iterator = lookupMethod(tree.expr.pos(),
3678 names.iterator,
3679 tree.expr.type,
3680 List.nil());
3681 Assert.check(types.isSameType(types.erasure(types.asSuper(iterator.type.getReturnType(), syms.iteratorType.tsym)), types.erasure(syms.iteratorType)));
3682 VarSymbol itvar = new VarSymbol(SYNTHETIC, names.fromString("i" + target.syntheticNameChar()),
3683 types.erasure(syms.iteratorType),
3684 currentMethodSym);
3685
3686 JCStatement init = make.
3687 VarDef(itvar, make.App(make.Select(tree.expr, iterator)
3688 .setType(types.erasure(iterator.type))));
3689
3690 Symbol hasNext = lookupMethod(tree.expr.pos(),
3691 names.hasNext,
3692 itvar.type,
3693 List.nil());
3694 JCMethodInvocation cond = make.App(make.Select(make.Ident(itvar), hasNext));
3695 Symbol next = lookupMethod(tree.expr.pos(),
3696 names.next,
3697 itvar.type,
3698 List.nil());
3699 JCExpression vardefinit = make.App(make.Select(make.Ident(itvar), next));
3700 if (tree.var.type.isPrimitive())
3701 vardefinit = make.TypeCast(types.cvarUpperBound(iteratorTarget), vardefinit);
3702 else
3703 vardefinit = make.TypeCast(tree.var.type, vardefinit);
3704 JCVariableDecl indexDef = (JCVariableDecl)make.VarDef(tree.var.mods,
3705 tree.var.name,
3706 tree.var.vartype,
3707 vardefinit).setType(tree.var.type);
3708 indexDef.sym = tree.var.sym;
3709 JCBlock body = make.Block(0, List.of(indexDef, tree.body));
3710 body.endpos = TreeInfo.endPos(tree.body);
3711 result = translate(make.
3712 ForLoop(List.of(init),
3713 cond,
3714 List.nil(),
3715 body));
3716 patchTargets(body, tree, result);
3717 }
3718
3719 public void visitVarDef(JCVariableDecl tree) {
3720 MethodSymbol oldMethodSym = currentMethodSym;
3721 int prevVariableIndex = variableIndex;
3722 tree.mods = translate(tree.mods);
3723 tree.vartype = translate(tree.vartype);
3724 if (currentMethodSym == null) {
3725 // A class or instance field initializer.
3726 currentMethodSym =
3727 new MethodSymbol((tree.mods.flags&STATIC) | BLOCK,
3728 names.empty, null,
3729 currentClass);
3730 }
3731 try {
3732 if (tree.init != null) tree.init = translate(tree.init, tree.type);
3733 result = tree;
3734 } finally {
3735 currentMethodSym = oldMethodSym;
3736 variableIndex = prevVariableIndex;
3737 }
3738 }
3739
3740 public void visitBlock(JCBlock tree) {
3741 MethodSymbol oldMethodSym = currentMethodSym;
3742 if (currentMethodSym == null) {
3743 // Block is a static or instance initializer.
3744 currentMethodSym =
3745 new MethodSymbol(tree.flags | BLOCK,
3746 names.empty, null,
3747 currentClass);
3748 }
3749 int prevVariableIndex = variableIndex;
3750 try {
3751 variableIndex = 0;
3752 super.visitBlock(tree);
3753 } finally {
3754 currentMethodSym = oldMethodSym;
3755 variableIndex = prevVariableIndex;
3756 }
3757 }
3758
3759 public void visitDoLoop(JCDoWhileLoop tree) {
3760 tree.body = translate(tree.body);
3761 tree.cond = translate(tree.cond, syms.booleanType);
3762 result = tree;
3763 }
3764
3765 public void visitWhileLoop(JCWhileLoop tree) {
3766 tree.cond = translate(tree.cond, syms.booleanType);
3767 tree.body = translate(tree.body);
3768 result = tree;
3769 }
3770
3771 public void visitForLoop(JCForLoop tree) {
3772 tree.init = translate(tree.init);
3773 if (tree.cond != null)
3774 tree.cond = translate(tree.cond, syms.booleanType);
3775 tree.step = translate(tree.step);
3776 tree.body = translate(tree.body);
3777 result = tree;
3778 }
3779
3780 public void visitReturn(JCReturn tree) {
3781 if (tree.expr != null)
3782 tree.expr = translate(tree.expr,
3783 currentRestype);
3784 result = tree;
3785 }
3786
3787 @Override
3788 public void visitLambda(JCLambda tree) {
3789 Type prevRestype = currentRestype;
3790 try {
3791 currentRestype = types.erasure(tree.getDescriptorType(types)).getReturnType();
3792 // represent void results as NO_TYPE, to avoid unnecessary boxing in boxIfNeeded
3793 if (currentRestype.hasTag(VOID))
3794 currentRestype = Type.noType;
3795 tree.body = tree.getBodyKind() == BodyKind.EXPRESSION ?
3796 translate((JCExpression) tree.body, currentRestype) :
3797 translate(tree.body);
3798 } finally {
3799 currentRestype = prevRestype;
3800 }
3801 result = tree;
3802 }
3803
3804 public void visitSwitch(JCSwitch tree) {
3805 List<JCCase> cases = tree.patternSwitch ? addDefaultIfNeeded(tree.patternSwitch,
3806 tree.wasEnumSelector,
3807 tree.cases)
3808 : tree.cases;
3809 handleSwitch(tree, tree.selector, cases);
3810 }
3811
3812 @Override
3813 public void visitSwitchExpression(JCSwitchExpression tree) {
3814 List<JCCase> cases = addDefaultIfNeeded(tree.patternSwitch, tree.wasEnumSelector, tree.cases);
3815 handleSwitch(tree, tree.selector, cases);
3816 }
3817
3818 private List<JCCase> addDefaultIfNeeded(boolean patternSwitch, boolean wasEnumSelector,
3819 List<JCCase> cases) {
3820 if (cases.stream().flatMap(c -> c.labels.stream()).noneMatch(p -> p.hasTag(Tag.DEFAULTCASELABEL))) {
3821 boolean matchException = useMatchException;
3822 matchException |= patternSwitch && !wasEnumSelector;
3823 Type exception = matchException ? syms.matchExceptionType
3824 : syms.incompatibleClassChangeErrorType;
3825 List<JCExpression> params = matchException ? List.of(makeNull(), makeNull())
3826 : List.nil();
3827 JCThrow thr = make.Throw(makeNewClass(exception, params));
3828 JCCase c = make.Case(JCCase.STATEMENT, List.of(make.DefaultCaseLabel()), null, List.of(thr), null);
3829 cases = cases.prepend(c);
3830 }
3831
3832 return cases;
3833 }
3834
3835 private void handleSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) {
3836 //expand multiple label cases:
3837 ListBuffer<JCCase> convertedCases = new ListBuffer<>();
3838
3839 for (JCCase c : cases) {
3840 switch (c.labels.size()) {
3841 case 0: //default
3842 case 1: //single label
3843 convertedCases.append(c);
3844 break;
3845 default: //multiple labels, expand:
3846 //case C1, C2, C3: ...
3847 //=>
3848 //case C1:
3849 //case C2:
3850 //case C3: ...
3851 List<JCCaseLabel> patterns = c.labels;
3852 while (patterns.tail.nonEmpty()) {
3853 convertedCases.append(make_at(c.pos()).Case(JCCase.STATEMENT,
3854 List.of(patterns.head),
3855 null,
3856 List.nil(),
3857 null));
3858 patterns = patterns.tail;
3859 }
3860 c.labels = patterns;
3861 convertedCases.append(c);
3862 break;
3863 }
3864 }
3865
3866 for (JCCase c : convertedCases) {
3867 if (c.caseKind == JCCase.RULE && c.completesNormally) {
3868 JCBreak b = make.at(TreeInfo.endPos(c.stats.last())).Break(null);
3869 b.target = tree;
3870 c.stats = c.stats.append(b);
3871 }
3872 }
3873
3874 cases = convertedCases.toList();
3875
3876 Type selsuper = types.supertype(selector.type);
3877 boolean enumSwitch = selsuper != null &&
3878 (selector.type.tsym.flags() & ENUM) != 0;
3879 boolean stringSwitch = selsuper != null &&
3880 types.isSameType(selector.type, syms.stringType);
3881 boolean boxedSwitch = !enumSwitch && !stringSwitch && !selector.type.isPrimitive();
3882 selector = translate(selector, selector.type);
3883 cases = translateCases(cases);
3884 if (tree.hasTag(SWITCH)) {
3885 ((JCSwitch) tree).selector = selector;
3886 ((JCSwitch) tree).cases = cases;
3887 } else if (tree.hasTag(SWITCH_EXPRESSION)) {
3888 ((JCSwitchExpression) tree).selector = selector;
3889 ((JCSwitchExpression) tree).cases = cases;
3890 } else {
3891 Assert.error();
3892 }
3893 if (enumSwitch) {
3894 result = visitEnumSwitch(tree, selector, cases);
3895 } else if (stringSwitch) {
3896 result = visitStringSwitch(tree, selector, cases);
3897 } else if (boxedSwitch) {
3898 //An switch over boxed primitive. Pattern matching switches are already translated
3899 //by TransPatterns, so all non-primitive types are only boxed primitives:
3900 result = visitBoxedPrimitiveSwitch(tree, selector, cases);
3901 } else {
3902 result = tree;
3903 }
3904 }
3905
3906 public JCTree visitEnumSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) {
3907 TypeSymbol enumSym = selector.type.tsym;
3908 EnumMapping map = mapForEnum(tree.pos(), enumSym);
3909 make_at(tree.pos());
3910 Symbol ordinalMethod = lookupMethod(tree.pos(),
3911 names.ordinal,
3912 selector.type,
3913 List.nil());
3914 JCExpression newSelector;
3915
3916 if (cases.stream().anyMatch(c -> TreeInfo.isNullCaseLabel(c.labels.head))) {
3917 //for enum switches with case null, do:
3918 //switch ($selector != null ? $mapVar[$selector.ordinal()] : -1) {...}
3919 //replacing case null with case -1:
3920 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC,
3921 names.fromString("s" + variableIndex++ + this.target.syntheticNameChar()),
3922 selector.type,
3923 currentMethodSym);
3924 JCStatement var = make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type);
3925 newSelector = map.switchValue(
3926 make.App(make.Select(make.Ident(dollar_s),
3927 ordinalMethod)));
3928 newSelector =
3929 make.LetExpr(List.of(var),
3930 make.Conditional(makeBinary(NE, make.Ident(dollar_s), makeNull()),
3931 newSelector,
3932 makeLit(syms.intType, -1))
3933 .setType(newSelector.type))
3934 .setType(newSelector.type);
3935 } else {
3936 newSelector = map.switchValue(
3937 make.App(make.Select(selector,
3938 ordinalMethod)));
3939 }
3940 ListBuffer<JCCase> newCases = new ListBuffer<>();
3941 for (JCCase c : cases) {
3942 if (c.labels.head.hasTag(CONSTANTCASELABEL)) {
3943 JCExpression pat;
3944 if (TreeInfo.isNullCaseLabel(c.labels.head)) {
3945 pat = makeLit(syms.intType, -1);
3946 } else {
3947 VarSymbol label = (VarSymbol)TreeInfo.symbol(((JCConstantCaseLabel) c.labels.head).expr);
3948 pat = map.caseValue(label);
3949 }
3950 newCases.append(make.Case(JCCase.STATEMENT, List.of(make.ConstantCaseLabel(pat)), null, c.stats, null));
3951 } else {
3952 newCases.append(c);
3953 }
3954 }
3955 JCTree enumSwitch;
3956 if (tree.hasTag(SWITCH)) {
3957 enumSwitch = make.Switch(newSelector, newCases.toList());
3958 } else if (tree.hasTag(SWITCH_EXPRESSION)) {
3959 enumSwitch = make.SwitchExpression(newSelector, newCases.toList());
3960 enumSwitch.setType(tree.type);
3961 } else {
3962 Assert.error();
3963 throw new AssertionError();
3964 }
3965 patchTargets(enumSwitch, tree, enumSwitch);
3966 return enumSwitch;
3967 }
3968
3969 public JCTree visitStringSwitch(JCTree tree, JCExpression selector, List<JCCase> caseList) {
3970 int alternatives = caseList.size();
3971
3972 if (alternatives == 0) { // Strange but legal possibility (only legal for switch statement)
3973 return make.at(tree.pos()).Exec(attr.makeNullCheck(selector));
3974 } else {
3975 /*
3976 * The general approach used is to translate a single
3977 * string switch statement into a series of two chained
3978 * switch statements: the first a synthesized statement
3979 * switching on the argument string's hash value and
3980 * computing a string's position in the list of original
3981 * case labels, if any, followed by a second switch on the
3982 * computed integer value. The second switch has the same
3983 * code structure as the original string switch statement
3984 * except that the string case labels are replaced with
3985 * positional integer constants starting at 0.
3986 *
3987 * The first switch statement can be thought of as an
3988 * inlined map from strings to their position in the case
3989 * label list. An alternate implementation would use an
3990 * actual Map for this purpose, as done for enum switches.
3991 *
3992 * With some additional effort, it would be possible to
3993 * use a single switch statement on the hash code of the
3994 * argument, but care would need to be taken to preserve
3995 * the proper control flow in the presence of hash
3996 * collisions and other complications, such as
3997 * fallthroughs. Switch statements with one or two
3998 * alternatives could also be specially translated into
3999 * if-then statements to omit the computation of the hash
4000 * code.
4001 *
4002 * The generated code assumes that the hashing algorithm
4003 * of String is the same in the compilation environment as
4004 * in the environment the code will run in. The string
4005 * hashing algorithm in the SE JDK has been unchanged
4006 * since at least JDK 1.2. Since the algorithm has been
4007 * specified since that release as well, it is very
4008 * unlikely to be changed in the future.
4009 *
4010 * Different hashing algorithms, such as the length of the
4011 * strings or a perfect hashing algorithm over the
4012 * particular set of case labels, could potentially be
4013 * used instead of String.hashCode.
4014 */
4015
4016 ListBuffer<JCStatement> stmtList = new ListBuffer<>();
4017
4018 // Map from String case labels to their original position in
4019 // the list of case labels.
4020 Map<String, Integer> caseLabelToPosition = new LinkedHashMap<>(alternatives + 1, 1.0f);
4021
4022 // Map of hash codes to the string case labels having that hashCode.
4023 Map<Integer, Set<String>> hashToString = new LinkedHashMap<>(alternatives + 1, 1.0f);
4024
4025 int casePosition = 0;
4026 JCCase nullCase = null;
4027 int nullCaseLabel = -1;
4028
4029 for(JCCase oneCase : caseList) {
4030 if (oneCase.labels.head.hasTag(CONSTANTCASELABEL)) {
4031 if (TreeInfo.isNullCaseLabel(oneCase.labels.head)) {
4032 nullCase = oneCase;
4033 nullCaseLabel = casePosition;
4034 } else {
4035 JCExpression expression = ((JCConstantCaseLabel) oneCase.labels.head).expr;
4036 String labelExpr = (String) expression.type.constValue();
4037 Integer mapping = caseLabelToPosition.put(labelExpr, casePosition);
4038 Assert.checkNull(mapping);
4039 int hashCode = labelExpr.hashCode();
4040
4041 Set<String> stringSet = hashToString.get(hashCode);
4042 if (stringSet == null) {
4043 stringSet = new LinkedHashSet<>(1, 1.0f);
4044 stringSet.add(labelExpr);
4045 hashToString.put(hashCode, stringSet);
4046 } else {
4047 boolean added = stringSet.add(labelExpr);
4048 Assert.check(added);
4049 }
4050 }
4051 }
4052 casePosition++;
4053 }
4054
4055 // Synthesize a switch statement that has the effect of
4056 // mapping from a string to the integer position of that
4057 // string in the list of case labels. This is done by
4058 // switching on the hashCode of the string followed by an
4059 // if-then-else chain comparing the input for equality
4060 // with all the case labels having that hash value.
4061
4062 /*
4063 * s$ = top of stack;
4064 * tmp$ = -1;
4065 * switch($s.hashCode()) {
4066 * case caseLabel.hashCode:
4067 * if (s$.equals("caseLabel_1")
4068 * tmp$ = caseLabelToPosition("caseLabel_1");
4069 * else if (s$.equals("caseLabel_2"))
4070 * tmp$ = caseLabelToPosition("caseLabel_2");
4071 * ...
4072 * break;
4073 * ...
4074 * }
4075 */
4076
4077 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC,
4078 names.fromString("s" + variableIndex++ + target.syntheticNameChar()),
4079 syms.stringType,
4080 currentMethodSym);
4081 stmtList.append(make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type));
4082
4083 VarSymbol dollar_tmp = new VarSymbol(SYNTHETIC,
4084 names.fromString("tmp" + variableIndex++ + target.syntheticNameChar()),
4085 syms.intType,
4086 currentMethodSym);
4087 JCVariableDecl dollar_tmp_def =
4088 (JCVariableDecl)make.VarDef(dollar_tmp, make.Literal(INT, -1)).setType(dollar_tmp.type);
4089 dollar_tmp_def.init.type = dollar_tmp.type = syms.intType;
4090 stmtList.append(dollar_tmp_def);
4091 ListBuffer<JCCase> caseBuffer = new ListBuffer<>();
4092 // hashCode will trigger nullcheck on original switch expression
4093 JCMethodInvocation hashCodeCall = makeCall(make.Ident(dollar_s),
4094 names.hashCode,
4095 List.nil()).setType(syms.intType);
4096 JCSwitch switch1 = make.Switch(hashCodeCall,
4097 caseBuffer.toList());
4098 for(Map.Entry<Integer, Set<String>> entry : hashToString.entrySet()) {
4099 int hashCode = entry.getKey();
4100 Set<String> stringsWithHashCode = entry.getValue();
4101 Assert.check(stringsWithHashCode.size() >= 1);
4102
4103 JCStatement elsepart = null;
4104 for(String caseLabel : stringsWithHashCode ) {
4105 JCMethodInvocation stringEqualsCall = makeCall(make.Ident(dollar_s),
4106 names.equals,
4107 List.of(make.Literal(caseLabel)));
4108 elsepart = make.If(stringEqualsCall,
4109 make.Exec(make.Assign(make.Ident(dollar_tmp),
4110 make.Literal(caseLabelToPosition.get(caseLabel))).
4111 setType(dollar_tmp.type)),
4112 elsepart);
4113 }
4114
4115 ListBuffer<JCStatement> lb = new ListBuffer<>();
4116 JCBreak breakStmt = make.Break(null);
4117 breakStmt.target = switch1;
4118 lb.append(elsepart).append(breakStmt);
4119
4120 caseBuffer.append(make.Case(JCCase.STATEMENT,
4121 List.of(make.ConstantCaseLabel(make.Literal(hashCode))),
4122 null,
4123 lb.toList(),
4124 null));
4125 }
4126
4127 switch1.cases = caseBuffer.toList();
4128
4129 if (nullCase != null) {
4130 stmtList.append(make.If(makeBinary(NE, make.Ident(dollar_s), makeNull()), switch1, make.Exec(make.Assign(make.Ident(dollar_tmp),
4131 make.Literal(nullCaseLabel)).
4132 setType(dollar_tmp.type))).setType(syms.intType));
4133 } else {
4134 stmtList.append(switch1);
4135 }
4136
4137 // Make isomorphic switch tree replacing string labels
4138 // with corresponding integer ones from the label to
4139 // position map.
4140
4141 ListBuffer<JCCase> lb = new ListBuffer<>();
4142 for(JCCase oneCase : caseList ) {
4143 boolean isDefault = !oneCase.labels.head.hasTag(CONSTANTCASELABEL);
4144 JCExpression caseExpr;
4145 if (isDefault)
4146 caseExpr = null;
4147 else if (oneCase == nullCase) {
4148 caseExpr = make.Literal(nullCaseLabel);
4149 } else {
4150 JCExpression expression = ((JCConstantCaseLabel) oneCase.labels.head).expr;
4151 String name = (String) TreeInfo.skipParens(expression)
4152 .type.constValue();
4153 caseExpr = make.Literal(caseLabelToPosition.get(name));
4154 }
4155
4156 lb.append(make.Case(JCCase.STATEMENT, caseExpr == null ? List.of(make.DefaultCaseLabel())
4157 : List.of(make.ConstantCaseLabel(caseExpr)),
4158 null,
4159 oneCase.stats, null));
4160 }
4161
4162 if (tree.hasTag(SWITCH)) {
4163 JCSwitch switch2 = make.Switch(make.Ident(dollar_tmp), lb.toList());
4164 // Rewire up old unlabeled break statements to the
4165 // replacement switch being created.
4166 patchTargets(switch2, tree, switch2);
4167
4168 stmtList.append(switch2);
4169
4170 JCBlock res = make.Block(0L, stmtList.toList());
4171 res.endpos = TreeInfo.endPos(tree);
4172 return res;
4173 } else {
4174 JCSwitchExpression switch2 = make.SwitchExpression(make.Ident(dollar_tmp), lb.toList());
4175
4176 // Rewire up old unlabeled break statements to the
4177 // replacement switch being created.
4178 patchTargets(switch2, tree, switch2);
4179
4180 switch2.setType(tree.type);
4181
4182 LetExpr res = make.LetExpr(stmtList.toList(), switch2);
4183
4184 res.needsCond = true;
4185 res.setType(tree.type);
4186
4187 return res;
4188 }
4189 }
4190 }
4191
4192 private JCTree visitBoxedPrimitiveSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) {
4193 JCExpression newSelector;
4194
4195 if (cases.stream().anyMatch(c -> TreeInfo.isNullCaseLabel(c.labels.head))) {
4196 //a switch over a boxed primitive, with a null case. Pick two constants that are
4197 //not used by any branch in the case (c1 and c2), close to other constants that are
4198 //used in the switch. Then do:
4199 //switch ($selector != null ? $selector != c1 ? $selector : c2 : c1) {...}
4200 //replacing case null with case c1
4201 Set<Integer> constants = new LinkedHashSet<>();
4202 JCCase nullCase = null;
4203
4204 for (JCCase c : cases) {
4205 if (TreeInfo.isNullCaseLabel(c.labels.head)) {
4206 nullCase = c;
4207 } else if (!c.labels.head.hasTag(DEFAULTCASELABEL)) {
4208 constants.add((int) ((JCConstantCaseLabel) c.labels.head).expr.type.constValue());
4209 }
4210 }
4211
4212 Assert.checkNonNull(nullCase);
4213
4214 int nullValue = constants.isEmpty() ? 0 : constants.iterator().next();
4215
4216 while (constants.contains(nullValue)) nullValue++;
4217
4218 constants.add(nullValue);
4219 nullCase.labels.head = make.ConstantCaseLabel(makeLit(syms.intType, nullValue));
4220
4221 int replacementValue = nullValue;
4222
4223 while (constants.contains(replacementValue)) replacementValue++;
4224
4225 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC,
4226 names.fromString("s" + variableIndex++ + this.target.syntheticNameChar()),
4227 selector.type,
4228 currentMethodSym);
4229 JCStatement var = make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type);
4230 JCExpression nullValueReplacement =
4231 make.Conditional(makeBinary(NE,
4232 unbox(make.Ident(dollar_s), syms.intType),
4233 makeLit(syms.intType, nullValue)),
4234 unbox(make.Ident(dollar_s), syms.intType),
4235 makeLit(syms.intType, replacementValue))
4236 .setType(syms.intType);
4237 JCExpression nullCheck =
4238 make.Conditional(makeBinary(NE, make.Ident(dollar_s), makeNull()),
4239 nullValueReplacement,
4240 makeLit(syms.intType, nullValue))
4241 .setType(syms.intType);
4242 newSelector = make.LetExpr(List.of(var), nullCheck).setType(syms.intType);
4243 } else {
4244 newSelector = unbox(selector, syms.intType);
4245 }
4246
4247 if (tree.hasTag(SWITCH)) {
4248 ((JCSwitch) tree).selector = newSelector;
4249 } else {
4250 ((JCSwitchExpression) tree).selector = newSelector;
4251 }
4252
4253 return tree;
4254 }
4255
4256 @Override
4257 public void visitBreak(JCBreak tree) {
4258 result = tree;
4259 }
4260
4261 @Override
4262 public void visitYield(JCYield tree) {
4263 tree.value = translate(tree.value, tree.target.type);
4264 result = tree;
4265 }
4266
4267 public void visitNewArray(JCNewArray tree) {
4268 tree.elemtype = translate(tree.elemtype);
4269 for (List<JCExpression> t = tree.dims; t.tail != null; t = t.tail)
4270 if (t.head != null) t.head = translate(t.head, syms.intType);
4271 tree.elems = translate(tree.elems, types.elemtype(tree.type));
4272 result = tree;
4273 }
4274
4275 public void visitSelect(JCFieldAccess tree) {
4276 // need to special case-access of the form C.super.x
4277 // these will always need an access method, unless C
4278 // is a default interface subclassed by the current class.
4279 boolean qualifiedSuperAccess =
4280 tree.selected.hasTag(SELECT) &&
4281 TreeInfo.name(tree.selected) == names._super &&
4282 !types.isDirectSuperInterface(((JCFieldAccess)tree.selected).selected.type.tsym, currentClass);
4283 tree.selected = translate(tree.selected);
4284 if (tree.name == names._class && tree.selected.type.isPrimitiveOrVoid()) {
4285 result = classOf(tree.selected);
4286 }
4287 else if (tree.name == names._super &&
4288 types.isDirectSuperInterface(tree.selected.type.tsym, currentClass)) {
4289 //default super call!! Not a classic qualified super call
4290 TypeSymbol supSym = tree.selected.type.tsym;
4291 Assert.checkNonNull(types.asSuper(currentClass.type, supSym));
4292 result = tree;
4293 }
4294 else if (tree.name == names._this || tree.name == names._super) {
4295 result = makeThis(tree.pos(), tree.selected.type.tsym);
4296 }
4297 else
4298 result = access(tree.sym, tree, enclOp, qualifiedSuperAccess);
4299 }
4300
4301 public void visitLetExpr(LetExpr tree) {
4302 tree.defs = translate(tree.defs);
4303 tree.expr = translate(tree.expr, tree.type);
4304 result = tree;
4305 }
4306
4307 // There ought to be nothing to rewrite here;
4308 // we don't generate code.
4309 public void visitAnnotation(JCAnnotation tree) {
4310 result = tree;
4311 }
4312
4313 @Override
4314 public void visitTry(JCTry tree) {
4315 if (tree.resources.nonEmpty()) {
4316 result = makeTwrTry(tree);
4317 return;
4318 }
4319
4320 boolean hasBody = tree.body.getStatements().nonEmpty();
4321 boolean hasCatchers = tree.catchers.nonEmpty();
4322 boolean hasFinally = tree.finalizer != null &&
4323 tree.finalizer.getStatements().nonEmpty();
4324
4325 if (!hasCatchers && !hasFinally) {
4326 result = translate(tree.body);
4327 return;
4328 }
4329
4330 if (!hasBody) {
4331 if (hasFinally) {
4332 result = translate(tree.finalizer);
4333 } else {
4334 result = translate(tree.body);
4335 }
4336 return;
4337 }
4338
4339 // no optimizations possible
4340 super.visitTry(tree);
4341 }
4342
4343 /* ************************************************************************
4344 * main method
4345 *************************************************************************/
4346
4347 /** Translate a toplevel class and return a list consisting of
4348 * the translated class and translated versions of all inner classes.
4349 * @param env The attribution environment current at the class definition.
4350 * We need this for resolving some additional symbols.
4351 * @param cdef The tree representing the class definition.
4352 */
4353 public List<JCTree> translateTopLevelClass(Env<AttrContext> env, JCTree cdef, TreeMaker make) {
4354 ListBuffer<JCTree> translated = null;
4355 try {
4356 attrEnv = env;
4357 this.make = make;
4358 endPosTable = env.toplevel.endPositions;
4359 currentClass = null;
4360 currentRestype = null;
4361 currentMethodDef = null;
4362 outermostClassDef = (cdef.hasTag(CLASSDEF)) ? (JCClassDecl)cdef : null;
4363 outermostMemberDef = null;
4364 this.translated = new ListBuffer<>();
4365 classdefs = new HashMap<>();
4366 actualSymbols = new HashMap<>();
4367 freevarCache = new HashMap<>();
4368 proxies = new HashMap<>();
4369 twrVars = WriteableScope.create(syms.noSymbol);
4370 outerThisStack = List.nil();
4371 accessNums = new HashMap<>();
4372 accessSyms = new HashMap<>();
4373 accessConstrs = new HashMap<>();
4374 accessConstrTags = List.nil();
4375 accessed = new ListBuffer<>();
4376 translate(cdef, (JCExpression)null);
4377 for (List<Symbol> l = accessed.toList(); l.nonEmpty(); l = l.tail)
4378 makeAccessible(l.head);
4379 for (EnumMapping map : enumSwitchMap.values())
4380 map.translate();
4381 checkConflicts(this.translated.toList());
4382 checkAccessConstructorTags();
4383 translated = this.translated;
4384 } finally {
4385 // note that recursive invocations of this method fail hard
4386 attrEnv = null;
4387 this.make = null;
4388 endPosTable = null;
4389 currentClass = null;
4390 currentRestype = null;
4391 currentMethodDef = null;
4392 outermostClassDef = null;
4393 outermostMemberDef = null;
4394 this.translated = null;
4395 classdefs = null;
4396 actualSymbols = null;
4397 freevarCache = null;
4398 proxies = null;
4399 outerThisStack = null;
4400 accessNums = null;
4401 accessSyms = null;
4402 accessConstrs = null;
4403 accessConstrTags = null;
4404 accessed = null;
4405 enumSwitchMap.clear();
4406 assertionsDisabledClassCache = null;
4407 }
4408 return translated.toList();
4409 }
4410
4411 // needed for the lambda deserialization method, which is expressed as a big switch on strings
4412 public JCMethodDecl translateMethod(Env<AttrContext> env, JCMethodDecl methodDecl, TreeMaker make) {
4413 try {
4414 this.attrEnv = env;
4415 this.make = make;
4416 this.currentClass = methodDecl.sym.enclClass();
4417 proxies = new HashMap<>();
4418 return translate(methodDecl);
4419 } finally {
4420 this.attrEnv = null;
4421 this.make = null;
4422 this.currentClass = null;
4423 // the two fields below are set when visiting the method
4424 this.currentMethodSym = null;
4425 this.currentMethodDef = null;
4426 this.proxies = null;
4427 }
4428 }
4429 }