1 /*
2 * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.javac.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.tree.*;
40 import com.sun.tools.javac.util.*;
41 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
42 import com.sun.tools.javac.util.List;
43
44 import com.sun.tools.javac.code.Symbol.*;
45 import com.sun.tools.javac.code.Symbol.OperatorSymbol.AccessCode;
46 import com.sun.tools.javac.resources.CompilerProperties.Errors;
47 import com.sun.tools.javac.tree.JCTree.*;
48 import com.sun.tools.javac.code.Type.*;
49
50 import com.sun.tools.javac.jvm.Target;
51 import com.sun.tools.javac.tree.EndPosTable;
52
53 import static com.sun.tools.javac.code.Flags.*;
54 import static com.sun.tools.javac.code.Flags.BLOCK;
55 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
56 import static com.sun.tools.javac.code.TypeTag.*;
57 import static com.sun.tools.javac.code.Kinds.Kind.*;
58 import com.sun.tools.javac.code.Source.Feature;
59 import static com.sun.tools.javac.jvm.ByteCodes.*;
60 import com.sun.tools.javac.tree.JCTree.JCBreak;
61 import com.sun.tools.javac.tree.JCTree.JCCase;
62 import com.sun.tools.javac.tree.JCTree.JCExpression;
63 import com.sun.tools.javac.tree.JCTree.JCExpressionStatement;
64
65 import static com.sun.tools.javac.tree.JCTree.JCOperatorExpression.OperandPos.LEFT;
66 import com.sun.tools.javac.tree.JCTree.JCSwitchExpression;
67
68 import static com.sun.tools.javac.tree.JCTree.Tag.*;
69
70 /** This pass translates away some syntactic sugar: inner classes,
71 * class literals, assertions, foreach loops, etc.
72 *
73 * <p><b>This is NOT part of any supported API.
74 * If you write code that depends on this, you do so at your own risk.
75 * This code and its internal interfaces are subject to change or
76 * deletion without notice.</b>
77 */
78 public class Lower extends TreeTranslator {
79 protected static final Context.Key<Lower> lowerKey = new Context.Key<>();
80
81 public static Lower instance(Context context) {
82 Lower instance = context.get(lowerKey);
83 if (instance == null)
84 instance = new Lower(context);
85 return instance;
86 }
87
88 private final Names names;
89 private final Log log;
90 private final Symtab syms;
91 private final Resolve rs;
92 private final Operators operators;
93 private final Check chk;
94 private final Attr attr;
95 private TreeMaker make;
96 private DiagnosticPosition make_pos;
97 private final ConstFold cfolder;
98 private final Target target;
99 private final TypeEnvs typeEnvs;
100 private final Name dollarAssertionsDisabled;
101 private final Types types;
102 private final TransTypes transTypes;
103 private final boolean debugLower;
104 private final boolean disableProtectedAccessors; // experimental
105 private final PkgInfo pkginfoOpt;
106 private final boolean optimizeOuterThis;
107 private final boolean nullCheckOuterThis;
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 nullCheckOuterThis = options.getBoolean("nullCheckOuterThis",
139 target.nullCheckOuterThisByDefault());
140 disableProtectedAccessors = options.isSet("disableProtectedAccessors");
141 Source source = Source.instance(context);
142 Preview preview = Preview.instance(context);
143 useMatchException = Feature.PATTERN_SWITCH.allowedInSource(source) &&
144 (preview.isEnabled() || !preview.isPreview(Feature.PATTERN_SWITCH));
145 typePairToName = TypePairs.initialize(syms);
146 this.allowValueClasses = (!preview.isPreview(Feature.VALUE_CLASSES) || preview.isEnabled()) &&
147 Feature.VALUE_CLASSES.allowedInSource(source);
148 }
149
150 /** The currently enclosing class.
151 */
152 ClassSymbol currentClass;
153
154 /** A queue of all translated classes.
155 */
156 ListBuffer<JCTree> translated;
157
158 /** Environment for symbol lookup, set by translateTopLevelClass.
159 */
160 Env<AttrContext> attrEnv;
161
162 /** A hash table mapping syntax trees to their ending source positions.
163 */
164 EndPosTable endPosTable;
165
166 /* ************************************************************************
167 * Global mappings
168 *************************************************************************/
169
170 /** A hash table mapping local classes to their definitions.
171 */
172 Map<ClassSymbol, JCClassDecl> classdefs;
173
174 /** A hash table mapping local classes to a list of pruned trees.
175 */
176 public Map<ClassSymbol, List<JCTree>> prunedTree = new WeakHashMap<>();
177
178 /** A hash table mapping virtual accessed symbols in outer subclasses
179 * to the actually referred symbol in superclasses.
180 */
181 Map<Symbol,Symbol> actualSymbols;
182
183 /**
184 * The current expected return type.
185 */
186 Type currentRestype;
187
188 /** The current method definition.
189 */
190 JCMethodDecl currentMethodDef;
191
192 /** The current method symbol.
193 */
194 MethodSymbol currentMethodSym;
195
196 /** The currently enclosing outermost class definition.
197 */
198 JCClassDecl outermostClassDef;
199
200 /** The currently enclosing outermost member definition.
201 */
202 JCTree outermostMemberDef;
203
204 /** A hash table mapping local classes to a set of outer this fields
205 */
206 public Map<ClassSymbol, Set<JCExpression>> initializerOuterThis = new WeakHashMap<>();
207
208 /** A navigator class for assembling a mapping from local class symbols
209 * to class definition trees.
210 * There is only one case; all other cases simply traverse down the tree.
211 */
212 class ClassMap extends TreeScanner {
213
214 /** All encountered class defs are entered into classdefs table.
215 */
216 public void visitClassDef(JCClassDecl tree) {
217 classdefs.put(tree.sym, tree);
218 super.visitClassDef(tree);
219 }
220 }
221 ClassMap classMap = new ClassMap();
222
223 /** Map a class symbol to its definition.
224 * @param c The class symbol of which we want to determine the definition.
225 */
226 JCClassDecl classDef(ClassSymbol c) {
227 // First lookup the class in the classdefs table.
228 JCClassDecl def = classdefs.get(c);
229 if (def == null && outermostMemberDef != null) {
230 // If this fails, traverse outermost member definition, entering all
231 // local classes into classdefs, and try again.
232 classMap.scan(outermostMemberDef);
233 def = classdefs.get(c);
234 }
235 if (def == null) {
236 // If this fails, traverse outermost class definition, entering all
237 // local classes into classdefs, and try again.
238 classMap.scan(outermostClassDef);
239 def = classdefs.get(c);
240 }
241 return def;
242 }
243
244 /**
245 * Get the enum constants for the given enum class symbol, if known.
246 * They will only be found if they are defined within the same top-level
247 * class as the class being compiled, so it's safe to assume that they
248 * can't change at runtime due to a recompilation.
249 */
250 List<Name> enumNamesFor(ClassSymbol c) {
251
252 // Find the class definition and verify it is an enum class
253 final JCClassDecl classDef = classDef(c);
254 if (classDef == null ||
255 (classDef.mods.flags & ENUM) == 0 ||
256 (types.supertype(currentClass.type).tsym.flags() & ENUM) != 0) {
257 return null;
258 }
259
260 // Gather the enum identifiers
261 ListBuffer<Name> idents = new ListBuffer<>();
262 for (List<JCTree> defs = classDef.defs; defs.nonEmpty(); defs=defs.tail) {
263 if (defs.head.hasTag(VARDEF) &&
264 (((JCVariableDecl) defs.head).mods.flags & ENUM) != 0) {
265 JCVariableDecl var = (JCVariableDecl)defs.head;
266 idents.append(var.name);
267 }
268 }
269 return idents.toList();
270 }
271
272 /** A hash table mapping class symbols to lists of free variables.
273 * accessed by them. Only free variables of the method immediately containing
274 * a class are associated with that class.
275 */
276 Map<ClassSymbol,List<VarSymbol>> freevarCache;
277
278 /** A navigator class for collecting the free variables accessed
279 * from a local class.
280 */
281 class FreeVarCollector extends CaptureScanner {
282
283 FreeVarCollector(JCTree ownerTree) {
284 super(ownerTree);
285 }
286
287 void addFreeVars(ClassSymbol c) {
288 List<VarSymbol> fvs = freevarCache.get(c);
289 if (fvs != null) {
290 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) {
291 addFreeVar(l.head);
292 }
293 }
294 }
295
296 /** If tree refers to a class instance creation expression
297 * add all free variables of the freshly created class.
298 */
299 public void visitNewClass(JCNewClass tree) {
300 ClassSymbol c = (ClassSymbol)tree.constructor.owner;
301 addFreeVars(c);
302 super.visitNewClass(tree);
303 }
304
305 /** If tree refers to a superclass constructor call,
306 * add all free variables of the superclass.
307 */
308 public void visitApply(JCMethodInvocation tree) {
309 if (TreeInfo.name(tree.meth) == names._super) {
310 addFreeVars((ClassSymbol) TreeInfo.symbol(tree.meth).owner);
311 }
312 super.visitApply(tree);
313 }
314 }
315
316 /** Return the variables accessed from within a local class, which
317 * are declared in the local class' owner.
318 * (in reverse order of first access).
319 */
320 List<VarSymbol> freevars(ClassSymbol c) {
321 List<VarSymbol> fvs = freevarCache.get(c);
322 if (fvs != null) {
323 return fvs;
324 }
325 FreeVarCollector collector = new FreeVarCollector(classDef(c));
326 fvs = collector.analyzeCaptures().reverse();
327 freevarCache.put(c, fvs);
328 return fvs;
329 }
330
331 Map<TypeSymbol,EnumMapping> enumSwitchMap = new LinkedHashMap<>();
332
333 EnumMapping mapForEnum(DiagnosticPosition pos, TypeSymbol enumClass) {
334
335 // If enum class is part of this compilation, just switch on ordinal value
336 if (enumClass.kind == TYP) {
337 final List<Name> idents = enumNamesFor((ClassSymbol)enumClass);
338 if (idents != null)
339 return new CompileTimeEnumMapping(idents);
340 }
341
342 // Map identifiers to ordinal values at runtime, and then switch on that
343 return enumSwitchMap.computeIfAbsent(enumClass, ec -> new RuntimeEnumMapping(pos, ec));
344 }
345
346 /** Generates a test value and corresponding cases for a switch on an enum type.
347 */
348 interface EnumMapping {
349
350 /** Given an expression for the enum value's ordinal, generate an expression for the switch statement.
351 */
352 JCExpression switchValue(JCExpression ordinalExpr);
353
354 /** Generate the switch statement case value corresponding to the given enum value.
355 */
356 JCLiteral caseValue(VarSymbol v);
357
358 default void translate() {
359 }
360 }
361
362 /** EnumMapping using compile-time constants. Only valid when compiling the enum class itself,
363 * because otherwise the ordinals we use could become obsolete if/when the enum class is recompiled.
364 */
365 class CompileTimeEnumMapping implements EnumMapping {
366
367 final List<Name> enumNames;
368
369 CompileTimeEnumMapping(List<Name> enumNames) {
370 Assert.check(enumNames != null);
371 this.enumNames = enumNames;
372 }
373
374 @Override
375 public JCExpression switchValue(JCExpression ordinalExpr) {
376 return ordinalExpr;
377 }
378
379 @Override
380 public JCLiteral caseValue(VarSymbol v) {
381 final int ordinal = enumNames.indexOf(v.name);
382 Assert.check(ordinal != -1);
383 return make.Literal(ordinal);
384 }
385 }
386
387 /** EnumMapping using run-time ordinal lookup.
388 *
389 * This builds a translation table to be used for enum switches.
390 *
391 * <p>For each enum that appears as the type of a switch
392 * expression, we maintain an EnumMapping to assist in the
393 * translation, as exemplified by the following example:
394 *
395 * <p>we translate
396 * <pre>
397 * switch(colorExpression) {
398 * case red: stmt1;
399 * case green: stmt2;
400 * }
401 * </pre>
402 * into
403 * <pre>
404 * switch(Outer$0.$EnumMap$Color[colorExpression.ordinal()]) {
405 * case 1: stmt1;
406 * case 2: stmt2
407 * }
408 * </pre>
409 * with the auxiliary table initialized as follows:
410 * <pre>
411 * class Outer$0 {
412 * synthetic final int[] $EnumMap$Color = new int[Color.values().length];
413 * static {
414 * try { $EnumMap$Color[red.ordinal()] = 1; } catch (NoSuchFieldError ex) {}
415 * try { $EnumMap$Color[green.ordinal()] = 2; } catch (NoSuchFieldError ex) {}
416 * }
417 * }
418 * </pre>
419 * class EnumMapping provides mapping data and support methods for this translation.
420 */
421 class RuntimeEnumMapping implements EnumMapping {
422 RuntimeEnumMapping(DiagnosticPosition pos, TypeSymbol forEnum) {
423 this.forEnum = forEnum;
424 this.values = new LinkedHashMap<>();
425 this.pos = pos;
426 Name varName = names
427 .fromString(target.syntheticNameChar() +
428 "SwitchMap" +
429 target.syntheticNameChar() +
430 ClassWriter.externalize(forEnum.type.tsym.flatName().toString())
431 .replace('/', '.')
432 .replace('.', target.syntheticNameChar()));
433 ClassSymbol outerCacheClass = outerCacheClass();
434 this.mapVar = new VarSymbol(STATIC | SYNTHETIC | FINAL,
435 varName,
436 new ArrayType(syms.intType, syms.arrayClass),
437 outerCacheClass);
438 enterSynthetic(pos, mapVar, outerCacheClass.members());
439 }
440
441 DiagnosticPosition pos = null;
442
443 // the next value to use
444 int next = 1; // 0 (unused map elements) go to the default label
445
446 // the enum for which this is a map
447 final TypeSymbol forEnum;
448
449 // the field containing the map
450 final VarSymbol mapVar;
451
452 // the mapped values
453 final Map<VarSymbol,Integer> values;
454
455 @Override
456 public JCExpression switchValue(JCExpression ordinalExpr) {
457 return make.Indexed(mapVar, ordinalExpr);
458 }
459
460 @Override
461 public JCLiteral caseValue(VarSymbol v) {
462 Integer result = values.get(v);
463 if (result == null)
464 values.put(v, result = next++);
465 return make.Literal(result);
466 }
467
468 // generate the field initializer for the map
469 @Override
470 public void translate() {
471 boolean prevAllowProtectedAccess = attrEnv.info.allowProtectedAccess;
472 try {
473 make.at(pos.getStartPosition());
474 attrEnv.info.allowProtectedAccess = true;
475 JCClassDecl owner = classDef((ClassSymbol)mapVar.owner);
476
477 // synthetic static final int[] $SwitchMap$Color = new int[Color.values().length];
478 MethodSymbol valuesMethod = lookupMethod(pos,
479 names.values,
480 forEnum.type,
481 List.nil());
482 JCExpression size = make // Color.values().length
483 .Select(make.App(make.QualIdent(valuesMethod)),
484 syms.lengthVar);
485 JCExpression mapVarInit = make
486 .NewArray(make.Type(syms.intType), List.of(size), null)
487 .setType(new ArrayType(syms.intType, syms.arrayClass));
488
489 // try { $SwitchMap$Color[red.ordinal()] = 1; } catch (java.lang.NoSuchFieldError ex) {}
490 ListBuffer<JCStatement> stmts = new ListBuffer<>();
491 Symbol ordinalMethod = lookupMethod(pos,
492 names.ordinal,
493 forEnum.type,
494 List.nil());
495 List<JCCatch> catcher = List.<JCCatch>nil()
496 .prepend(make.Catch(make.VarDef(new VarSymbol(PARAMETER, names.ex,
497 syms.noSuchFieldErrorType,
498 syms.noSymbol),
499 null),
500 make.Block(0, List.nil())));
501 for (Map.Entry<VarSymbol,Integer> e : values.entrySet()) {
502 VarSymbol enumerator = e.getKey();
503 Integer mappedValue = e.getValue();
504 JCExpression assign = make
505 .Assign(make.Indexed(mapVar,
506 make.App(make.Select(make.QualIdent(enumerator),
507 ordinalMethod))),
508 make.Literal(mappedValue))
509 .setType(syms.intType);
510 JCStatement exec = make.Exec(assign);
511 JCStatement _try = make.Try(make.Block(0, List.of(exec)), catcher, null);
512 stmts.append(_try);
513 }
514
515 owner.defs = owner.defs
516 .prepend(make.Block(STATIC, stmts.toList()))
517 .prepend(make.VarDef(mapVar, mapVarInit));
518 } finally {
519 attrEnv.info.allowProtectedAccess = prevAllowProtectedAccess;
520 }
521 }
522 }
523
524
525 /* ************************************************************************
526 * Tree building blocks
527 *************************************************************************/
528
529 /** Equivalent to make.at(pos.getStartPosition()) with side effect of caching
530 * pos as make_pos, for use in diagnostics.
531 **/
532 TreeMaker make_at(DiagnosticPosition pos) {
533 make_pos = pos;
534 return make.at(pos);
535 }
536
537 /** Make an attributed tree representing a literal. This will be an
538 * Ident node in the case of boolean literals, a Literal node in all
539 * other cases.
540 * @param type The literal's type.
541 * @param value The literal's value.
542 */
543 JCExpression makeLit(Type type, Object value) {
544 return make.Literal(type.getTag(), value).setType(type.constType(value));
545 }
546
547 /** Make an attributed tree representing null.
548 */
549 JCExpression makeNull() {
550 return makeLit(syms.botType, null);
551 }
552
553 /** Make an attributed class instance creation expression.
554 * @param ctype The class type.
555 * @param args The constructor arguments.
556 */
557 JCNewClass makeNewClass(Type ctype, List<JCExpression> args) {
558 JCNewClass tree = make.NewClass(null,
559 null, make.QualIdent(ctype.tsym), args, null);
560 tree.constructor = rs.resolveConstructor(
561 make_pos, attrEnv, ctype, TreeInfo.types(args), List.nil());
562 tree.type = ctype;
563 return tree;
564 }
565
566 /** Make an attributed unary expression.
567 * @param optag The operators tree tag.
568 * @param arg The operator's argument.
569 */
570 JCUnary makeUnary(JCTree.Tag optag, JCExpression arg) {
571 JCUnary tree = make.Unary(optag, arg);
572 tree.operator = operators.resolveUnary(tree, optag, arg.type);
573 tree.type = tree.operator.type.getReturnType();
574 return tree;
575 }
576
577 /** Make an attributed binary expression.
578 * @param optag The operators tree tag.
579 * @param lhs The operator's left argument.
580 * @param rhs The operator's right argument.
581 */
582 JCBinary makeBinary(JCTree.Tag optag, JCExpression lhs, JCExpression rhs) {
583 JCBinary tree = make.Binary(optag, lhs, rhs);
584 tree.operator = operators.resolveBinary(tree, optag, lhs.type, rhs.type);
585 tree.type = tree.operator.type.getReturnType();
586 return tree;
587 }
588
589 /** Make an attributed assignop expression.
590 * @param optag The operators tree tag.
591 * @param lhs The operator's left argument.
592 * @param rhs The operator's right argument.
593 */
594 JCAssignOp makeAssignop(JCTree.Tag optag, JCTree lhs, JCTree rhs) {
595 JCAssignOp tree = make.Assignop(optag, lhs, rhs);
596 tree.operator = operators.resolveBinary(tree, tree.getTag().noAssignOp(), lhs.type, rhs.type);
597 tree.type = lhs.type;
598 return tree;
599 }
600
601 /** Convert tree into string object, unless it has already a
602 * reference type..
603 */
604 JCExpression makeString(JCExpression tree) {
605 if (!tree.type.isPrimitiveOrVoid()) {
606 return tree;
607 } else {
608 Symbol valueOfSym = lookupMethod(tree.pos(),
609 names.valueOf,
610 syms.stringType,
611 List.of(tree.type));
612 return make.App(make.QualIdent(valueOfSym), List.of(tree));
613 }
614 }
615
616 /** Create an empty anonymous class definition and enter and complete
617 * its symbol. Return the class definition's symbol.
618 * and create
619 * @param flags The class symbol's flags
620 * @param owner The class symbol's owner
621 */
622 JCClassDecl makeEmptyClass(long flags, ClassSymbol owner) {
623 return makeEmptyClass(flags, owner, null, true);
624 }
625
626 JCClassDecl makeEmptyClass(long flags, ClassSymbol owner, Name flatname,
627 boolean addToDefs) {
628 // Create class symbol.
629 ClassSymbol c = syms.defineClass(names.empty, owner);
630 if (flatname != null) {
631 c.flatname = flatname;
632 } else {
633 c.flatname = chk.localClassName(c);
634 }
635 c.sourcefile = owner.sourcefile;
636 c.completer = Completer.NULL_COMPLETER;
637 c.members_field = WriteableScope.create(c);
638 c.flags_field = flags;
639 ClassType ctype = (ClassType) c.type;
640 ctype.supertype_field = syms.objectType;
641 ctype.interfaces_field = List.nil();
642
643 JCClassDecl odef = classDef(owner);
644
645 // Enter class symbol in owner scope and compiled table.
646 enterSynthetic(odef.pos(), c, owner.members());
647 chk.putCompiled(c);
648
649 // Create class definition tree.
650 JCClassDecl cdef = make.ClassDef(
651 make.Modifiers(flags), names.empty,
652 List.nil(),
653 null, List.nil(), List.nil());
654 cdef.sym = c;
655 cdef.type = c.type;
656
657 // Append class definition tree to owner's definitions.
658 if (addToDefs) odef.defs = odef.defs.prepend(cdef);
659 return cdef;
660 }
661
662 /* ************************************************************************
663 * Symbol manipulation utilities
664 *************************************************************************/
665
666 /** Enter a synthetic symbol in a given scope, but complain if there was already one there.
667 * @param pos Position for error reporting.
668 * @param sym The symbol.
669 * @param s The scope.
670 */
671 private void enterSynthetic(DiagnosticPosition pos, Symbol sym, WriteableScope s) {
672 s.enter(sym);
673 }
674
675 /** Create a fresh synthetic name within a given scope - the unique name is
676 * obtained by appending '$' chars at the end of the name until no match
677 * is found.
678 *
679 * @param name base name
680 * @param s scope in which the name has to be unique
681 * @return fresh synthetic name
682 */
683 private Name makeSyntheticName(Name name, Scope s) {
684 do {
685 name = name.append(
686 target.syntheticNameChar(),
687 names.empty);
688 } while (lookupSynthetic(name, s) != null);
689 return name;
690 }
691
692 /** Check whether synthetic symbols generated during lowering conflict
693 * with user-defined symbols.
694 *
695 * @param translatedTrees lowered class trees
696 */
697 void checkConflicts(List<JCTree> translatedTrees) {
698 for (JCTree t : translatedTrees) {
699 t.accept(conflictsChecker);
700 }
701 }
702
703 JCTree.Visitor conflictsChecker = new TreeScanner() {
704
705 TypeSymbol currentClass;
706
707 @Override
708 public void visitMethodDef(JCMethodDecl that) {
709 checkConflicts(that.pos(), that.sym, currentClass);
710 super.visitMethodDef(that);
711 }
712
713 @Override
714 public void visitVarDef(JCVariableDecl that) {
715 if (that.sym.owner.kind == TYP) {
716 checkConflicts(that.pos(), that.sym, currentClass);
717 }
718 super.visitVarDef(that);
719 }
720
721 @Override
722 public void visitClassDef(JCClassDecl that) {
723 TypeSymbol prevCurrentClass = currentClass;
724 currentClass = that.sym;
725 try {
726 super.visitClassDef(that);
727 }
728 finally {
729 currentClass = prevCurrentClass;
730 }
731 }
732
733 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) {
734 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) {
735 for (Symbol sym2 : ct.tsym.members().getSymbolsByName(sym.name, NON_RECURSIVE)) {
736 // VM allows methods and variables with differing types
737 if (sym.kind == sym2.kind &&
738 types.isSameType(types.erasure(sym.type), types.erasure(sym2.type)) &&
739 sym != sym2 &&
740 (sym.flags() & Flags.SYNTHETIC) != (sym2.flags() & Flags.SYNTHETIC) &&
741 (sym.flags() & BRIDGE) == 0 && (sym2.flags() & BRIDGE) == 0) {
742 syntheticError(pos, (sym2.flags() & SYNTHETIC) == 0 ? sym2 : sym);
743 return;
744 }
745 }
746 }
747 }
748
749 /** Report a conflict between a user symbol and a synthetic symbol.
750 */
751 private void syntheticError(DiagnosticPosition pos, Symbol sym) {
752 if (!sym.type.isErroneous()) {
753 log.error(pos, Errors.CannotGenerateClass(sym.location(), Fragments.SyntheticNameConflict(sym, sym.location())));
754 }
755 }
756 };
757
758 /** Look up a synthetic name in a given scope.
759 * @param s The scope.
760 * @param name The name.
761 */
762 private Symbol lookupSynthetic(Name name, Scope s) {
763 Symbol sym = s.findFirst(name);
764 return (sym==null || (sym.flags()&SYNTHETIC)==0) ? null : sym;
765 }
766
767 /** Look up a method in a given scope.
768 */
769 private MethodSymbol lookupMethod(DiagnosticPosition pos, Name name, Type qual, List<Type> args) {
770 return rs.resolveInternalMethod(pos, attrEnv, qual, name, args, List.nil());
771 }
772
773 /** Anon inner classes are used as access constructor tags.
774 * accessConstructorTag will use an existing anon class if one is available,
775 * and synthesize a class (with makeEmptyClass) if one is not available.
776 * However, there is a small possibility that an existing class will not
777 * be generated as expected if it is inside a conditional with a constant
778 * expression. If that is found to be the case, create an empty class tree here.
779 */
780 private void checkAccessConstructorTags() {
781 for (List<ClassSymbol> l = accessConstrTags; l.nonEmpty(); l = l.tail) {
782 ClassSymbol c = l.head;
783 if (isTranslatedClassAvailable(c))
784 continue;
785 // Create class definition tree.
786 // IDENTITY_TYPE will be interpreted as ACC_SUPER for older class files so we are fine
787 JCClassDecl cdec = makeEmptyClass(STATIC | SYNTHETIC | IDENTITY_TYPE,
788 c.outermostClass(), c.flatname, false);
789 swapAccessConstructorTag(c, cdec.sym);
790 translated.append(cdec);
791 }
792 }
793 // where
794 private boolean isTranslatedClassAvailable(ClassSymbol c) {
795 for (JCTree tree: translated) {
796 if (tree.hasTag(CLASSDEF)
797 && ((JCClassDecl) tree).sym == c) {
798 return true;
799 }
800 }
801 return false;
802 }
803
804 void swapAccessConstructorTag(ClassSymbol oldCTag, ClassSymbol newCTag) {
805 for (MethodSymbol methodSymbol : accessConstrs.values()) {
806 Assert.check(methodSymbol.type.hasTag(METHOD));
807 MethodType oldMethodType =
808 (MethodType)methodSymbol.type;
809 if (oldMethodType.argtypes.head.tsym == oldCTag)
810 methodSymbol.type =
811 types.createMethodTypeWithParameters(oldMethodType,
812 oldMethodType.getParameterTypes().tail
813 .prepend(newCTag.erasure(types)));
814 }
815 }
816
817 /* ************************************************************************
818 * Access methods
819 *************************************************************************/
820
821 /** A mapping from symbols to their access numbers.
822 */
823 private Map<Symbol,Integer> accessNums;
824
825 /** A mapping from symbols to an array of access symbols, indexed by
826 * access code.
827 */
828 private Map<Symbol,MethodSymbol[]> accessSyms;
829
830 /** A mapping from (constructor) symbols to access constructor symbols.
831 */
832 private Map<Symbol,MethodSymbol> accessConstrs;
833
834 /** A list of all class symbols used for access constructor tags.
835 */
836 private List<ClassSymbol> accessConstrTags;
837
838 /** A queue for all accessed symbols.
839 */
840 private ListBuffer<Symbol> accessed;
841
842 /** return access code for identifier,
843 * @param tree The tree representing the identifier use.
844 * @param enclOp The closest enclosing operation node of tree,
845 * null if tree is not a subtree of an operation.
846 */
847 private static int accessCode(JCTree tree, JCTree enclOp) {
848 if (enclOp == null)
849 return AccessCode.DEREF.code;
850 else if (enclOp.hasTag(ASSIGN) &&
851 tree == TreeInfo.skipParens(((JCAssign) enclOp).lhs))
852 return AccessCode.ASSIGN.code;
853 else if ((enclOp.getTag().isIncOrDecUnaryOp() || enclOp.getTag().isAssignop()) &&
854 tree == TreeInfo.skipParens(((JCOperatorExpression) enclOp).getOperand(LEFT)))
855 return (((JCOperatorExpression) enclOp).operator).getAccessCode(enclOp.getTag());
856 else
857 return AccessCode.DEREF.code;
858 }
859
860 /** Return binary operator that corresponds to given access code.
861 */
862 private OperatorSymbol binaryAccessOperator(int acode, Tag tag) {
863 return operators.lookupBinaryOp(op -> op.getAccessCode(tag) == acode);
864 }
865
866 /** Return tree tag for assignment operation corresponding
867 * to given binary operator.
868 */
869 private static JCTree.Tag treeTag(OperatorSymbol operator) {
870 switch (operator.opcode) {
871 case ByteCodes.ior: case ByteCodes.lor:
872 return BITOR_ASG;
873 case ByteCodes.ixor: case ByteCodes.lxor:
874 return BITXOR_ASG;
875 case ByteCodes.iand: case ByteCodes.land:
876 return BITAND_ASG;
877 case ByteCodes.ishl: case ByteCodes.lshl:
878 case ByteCodes.ishll: case ByteCodes.lshll:
879 return SL_ASG;
880 case ByteCodes.ishr: case ByteCodes.lshr:
881 case ByteCodes.ishrl: case ByteCodes.lshrl:
882 return SR_ASG;
883 case ByteCodes.iushr: case ByteCodes.lushr:
884 case ByteCodes.iushrl: case ByteCodes.lushrl:
885 return USR_ASG;
886 case ByteCodes.iadd: case ByteCodes.ladd:
887 case ByteCodes.fadd: case ByteCodes.dadd:
888 case ByteCodes.string_add:
889 return PLUS_ASG;
890 case ByteCodes.isub: case ByteCodes.lsub:
891 case ByteCodes.fsub: case ByteCodes.dsub:
892 return MINUS_ASG;
893 case ByteCodes.imul: case ByteCodes.lmul:
894 case ByteCodes.fmul: case ByteCodes.dmul:
895 return MUL_ASG;
896 case ByteCodes.idiv: case ByteCodes.ldiv:
897 case ByteCodes.fdiv: case ByteCodes.ddiv:
898 return DIV_ASG;
899 case ByteCodes.imod: case ByteCodes.lmod:
900 case ByteCodes.fmod: case ByteCodes.dmod:
901 return MOD_ASG;
902 default:
903 throw new AssertionError();
904 }
905 }
906
907 /** The name of the access method with number `anum' and access code `acode'.
908 */
909 Name accessName(int anum, int acode) {
910 return names.fromString(
911 "access" + target.syntheticNameChar() + anum + acode / 10 + acode % 10);
912 }
913
914 /** Return access symbol for a private or protected symbol from an inner class.
915 * @param sym The accessed private symbol.
916 * @param tree The accessing tree.
917 * @param enclOp The closest enclosing operation node of tree,
918 * null if tree is not a subtree of an operation.
919 * @param protAccess Is access to a protected symbol in another
920 * package?
921 * @param refSuper Is access via a (qualified) C.super?
922 */
923 MethodSymbol accessSymbol(Symbol sym, JCTree tree, JCTree enclOp,
924 boolean protAccess, boolean refSuper) {
925 ClassSymbol accOwner = refSuper && protAccess
926 // For access via qualified super (T.super.x), place the
927 // access symbol on T.
928 ? (ClassSymbol)((JCFieldAccess) tree).selected.type.tsym
929 // Otherwise pretend that the owner of an accessed
930 // protected symbol is the enclosing class of the current
931 // class which is a subclass of the symbol's owner.
932 : accessClass(sym, protAccess, tree);
933
934 Symbol vsym = sym;
935 if (sym.owner != accOwner) {
936 vsym = sym.clone(accOwner);
937 actualSymbols.put(vsym, sym);
938 }
939
940 Integer anum // The access number of the access method.
941 = accessNums.get(vsym);
942 if (anum == null) {
943 anum = accessed.length();
944 accessNums.put(vsym, anum);
945 accessSyms.put(vsym, new MethodSymbol[AccessCode.numberOfAccessCodes]);
946 accessed.append(vsym);
947 // System.out.println("accessing " + vsym + " in " + vsym.location());
948 }
949
950 int acode; // The access code of the access method.
951 List<Type> argtypes; // The argument types of the access method.
952 Type restype; // The result type of the access method.
953 List<Type> thrown; // The thrown exceptions of the access method.
954 switch (vsym.kind) {
955 case VAR:
956 acode = accessCode(tree, enclOp);
957 if (acode >= AccessCode.FIRSTASGOP.code) {
958 OperatorSymbol operator = binaryAccessOperator(acode, enclOp.getTag());
959 if (operator.opcode == string_add)
960 argtypes = List.of(syms.objectType);
961 else
962 argtypes = operator.type.getParameterTypes().tail;
963 } else if (acode == AccessCode.ASSIGN.code)
964 argtypes = List.of(vsym.erasure(types));
965 else
966 argtypes = List.nil();
967 restype = vsym.erasure(types);
968 thrown = List.nil();
969 break;
970 case MTH:
971 acode = AccessCode.DEREF.code;
972 argtypes = vsym.erasure(types).getParameterTypes();
973 restype = vsym.erasure(types).getReturnType();
974 thrown = vsym.type.getThrownTypes();
975 break;
976 default:
977 throw new AssertionError();
978 }
979
980 // For references via qualified super, increment acode by one,
981 // making it odd.
982 if (protAccess && refSuper) acode++;
983
984 // Instance access methods get instance as first parameter.
985 // For protected symbols this needs to be the instance as a member
986 // of the type containing the accessed symbol, not the class
987 // containing the access method.
988 if ((vsym.flags() & STATIC) == 0) {
989 argtypes = argtypes.prepend(vsym.owner.erasure(types));
990 }
991 MethodSymbol[] accessors = accessSyms.get(vsym);
992 MethodSymbol accessor = accessors[acode];
993 if (accessor == null) {
994 accessor = new MethodSymbol(
995 STATIC | SYNTHETIC | (accOwner.isInterface() ? PUBLIC : 0),
996 accessName(anum.intValue(), acode),
997 new MethodType(argtypes, restype, thrown, syms.methodClass),
998 accOwner);
999 enterSynthetic(tree.pos(), accessor, accOwner.members());
1000 accessors[acode] = accessor;
1001 }
1002 return accessor;
1003 }
1004
1005 /** The qualifier to be used for accessing a symbol in an outer class.
1006 * This is either C.sym or C.this.sym, depending on whether or not
1007 * sym is static.
1008 * @param sym The accessed symbol.
1009 */
1010 JCExpression accessBase(DiagnosticPosition pos, Symbol sym) {
1011 return (sym.flags() & STATIC) != 0
1012 ? access(make.at(pos.getStartPosition()).QualIdent(sym.owner))
1013 : makeOwnerThis(pos, sym, true);
1014 }
1015
1016 /** Do we need an access method to reference private symbol?
1017 */
1018 boolean needsPrivateAccess(Symbol sym) {
1019 if (target.hasNestmateAccess()) {
1020 return false;
1021 }
1022 if ((sym.flags() & PRIVATE) == 0 || sym.owner == currentClass) {
1023 return false;
1024 } else if (sym.name == names.init && sym.owner.isDirectlyOrIndirectlyLocal()) {
1025 // private constructor in local class: relax protection
1026 sym.flags_field &= ~PRIVATE;
1027 return false;
1028 } else {
1029 return true;
1030 }
1031 }
1032
1033 /** Do we need an access method to reference symbol in other package?
1034 */
1035 boolean needsProtectedAccess(Symbol sym, JCTree tree) {
1036 if (disableProtectedAccessors) return false;
1037 if ((sym.flags() & PROTECTED) == 0 ||
1038 sym.owner.owner == currentClass.owner || // fast special case
1039 sym.packge() == currentClass.packge())
1040 return false;
1041 if (!currentClass.isSubClass(sym.owner, types))
1042 return true;
1043 if ((sym.flags() & STATIC) != 0 ||
1044 !tree.hasTag(SELECT) ||
1045 TreeInfo.name(((JCFieldAccess) tree).selected) == names._super)
1046 return false;
1047 return !((JCFieldAccess) tree).selected.type.tsym.isSubClass(currentClass, types);
1048 }
1049
1050 /** The class in which an access method for given symbol goes.
1051 * @param sym The access symbol
1052 * @param protAccess Is access to a protected symbol in another
1053 * package?
1054 */
1055 ClassSymbol accessClass(Symbol sym, boolean protAccess, JCTree tree) {
1056 if (protAccess) {
1057 Symbol qualifier = null;
1058 ClassSymbol c = currentClass;
1059 if (tree.hasTag(SELECT) && (sym.flags() & STATIC) == 0) {
1060 qualifier = ((JCFieldAccess) tree).selected.type.tsym;
1061 while (!qualifier.isSubClass(c, types)) {
1062 c = c.owner.enclClass();
1063 }
1064 return c;
1065 } else {
1066 while (!c.isSubClass(sym.owner, types)) {
1067 c = c.owner.enclClass();
1068 }
1069 }
1070 return c;
1071 } else {
1072 // the symbol is private
1073 return sym.owner.enclClass();
1074 }
1075 }
1076
1077 private boolean noClassDefIn(JCTree tree) {
1078 var scanner = new TreeScanner() {
1079 boolean noClassDef = true;
1080 @Override
1081 public void visitClassDef(JCClassDecl tree) {
1082 noClassDef = false;
1083 }
1084 };
1085 scanner.scan(tree);
1086 return scanner.noClassDef;
1087 }
1088
1089 private void addPrunedInfo(JCTree tree) {
1090 List<JCTree> infoList = prunedTree.get(currentClass);
1091 infoList = (infoList == null) ? List.of(tree) : infoList.prepend(tree);
1092 prunedTree.put(currentClass, infoList);
1093 }
1094
1095 /** Ensure that identifier is accessible, return tree accessing the identifier.
1096 * @param sym The accessed symbol.
1097 * @param tree The tree referring to the symbol.
1098 * @param enclOp The closest enclosing operation node of tree,
1099 * null if tree is not a subtree of an operation.
1100 * @param refSuper Is access via a (qualified) C.super?
1101 */
1102 JCExpression access(Symbol sym, JCExpression tree, JCExpression enclOp, boolean refSuper) {
1103 // Access a free variable via its proxy, or its proxy's proxy
1104 while (sym.kind == VAR && sym.owner.kind == MTH &&
1105 sym.owner.enclClass() != currentClass) {
1106 // A constant is replaced by its constant value.
1107 Object cv = ((VarSymbol)sym).getConstValue();
1108 if (cv != null) {
1109 make.at(tree.pos);
1110 return makeLit(sym.type, cv);
1111 }
1112 // Otherwise replace the variable by its proxy.
1113 sym = proxies.get(sym);
1114 Assert.check(sym != null && (sym.flags_field & FINAL) != 0);
1115 tree = make.at(tree.pos).Ident(sym);
1116 }
1117 JCExpression base = (tree.hasTag(SELECT)) ? ((JCFieldAccess) tree).selected : null;
1118 switch (sym.kind) {
1119 case TYP:
1120 if (sym.owner.kind != PCK) {
1121 // Convert type idents to
1122 // <flat name> or <package name> . <flat name>
1123 Name flatname = Convert.shortName(sym.flatName());
1124 while (base != null &&
1125 TreeInfo.symbol(base) != null &&
1126 TreeInfo.symbol(base).kind != PCK) {
1127 base = (base.hasTag(SELECT))
1128 ? ((JCFieldAccess) base).selected
1129 : null;
1130 }
1131 if (tree.hasTag(IDENT)) {
1132 ((JCIdent) tree).name = flatname;
1133 } else if (base == null) {
1134 tree = make.at(tree.pos).Ident(sym);
1135 ((JCIdent) tree).name = flatname;
1136 } else {
1137 ((JCFieldAccess) tree).selected = base;
1138 ((JCFieldAccess) tree).name = flatname;
1139 }
1140 }
1141 break;
1142 case MTH: case VAR:
1143 if (sym.owner.kind == TYP) {
1144
1145 // Access methods are required for
1146 // - private members,
1147 // - protected members in a superclass of an
1148 // enclosing class contained in another package.
1149 // - all non-private members accessed via a qualified super.
1150 boolean protAccess = refSuper && !needsPrivateAccess(sym)
1151 || needsProtectedAccess(sym, tree);
1152 boolean accReq = protAccess || needsPrivateAccess(sym);
1153
1154 // A base has to be supplied for
1155 // - simple identifiers accessing variables in outer classes.
1156 boolean baseReq =
1157 base == null &&
1158 sym.owner != syms.predefClass &&
1159 !sym.isMemberOf(currentClass, types);
1160
1161 if (accReq || baseReq) {
1162 make.at(tree.pos);
1163
1164 // Constants are replaced by their constant value.
1165 if (sym.kind == VAR) {
1166 Object cv = ((VarSymbol)sym).getConstValue();
1167 if (cv != null) {
1168 addPrunedInfo(tree);
1169 return makeLit(sym.type, cv);
1170 }
1171 }
1172
1173 // Private variables and methods are replaced by calls
1174 // to their access methods.
1175 if (accReq) {
1176 List<JCExpression> args = List.nil();
1177 if ((sym.flags() & STATIC) == 0) {
1178 // Instance access methods get instance
1179 // as first parameter.
1180 if (base == null)
1181 base = makeOwnerThis(tree.pos(), sym, true);
1182 args = args.prepend(base);
1183 base = null; // so we don't duplicate code
1184 }
1185 Symbol access = accessSymbol(sym, tree,
1186 enclOp, protAccess,
1187 refSuper);
1188 JCExpression receiver = make.Select(
1189 base != null ? base : make.QualIdent(access.owner),
1190 access);
1191 return make.App(receiver, args);
1192
1193 // Other accesses to members of outer classes get a
1194 // qualifier.
1195 } else if (baseReq) {
1196 return make.at(tree.pos).Select(
1197 accessBase(tree.pos(), sym), sym).setType(tree.type);
1198 }
1199 }
1200 }
1201 }
1202 return tree;
1203 }
1204
1205 /** Ensure that identifier is accessible, return tree accessing the identifier.
1206 * @param tree The identifier tree.
1207 */
1208 JCExpression access(JCExpression tree) {
1209 Symbol sym = TreeInfo.symbol(tree);
1210 return sym == null ? tree : access(sym, tree, null, false);
1211 }
1212
1213 /** Return access constructor for a private constructor,
1214 * or the constructor itself, if no access constructor is needed.
1215 * @param pos The position to report diagnostics, if any.
1216 * @param constr The private constructor.
1217 */
1218 Symbol accessConstructor(DiagnosticPosition pos, Symbol constr) {
1219 if (needsPrivateAccess(constr)) {
1220 ClassSymbol accOwner = constr.owner.enclClass();
1221 MethodSymbol aconstr = accessConstrs.get(constr);
1222 if (aconstr == null) {
1223 List<Type> argtypes = constr.type.getParameterTypes();
1224 if ((accOwner.flags_field & ENUM) != 0)
1225 argtypes = argtypes
1226 .prepend(syms.intType)
1227 .prepend(syms.stringType);
1228 aconstr = new MethodSymbol(
1229 SYNTHETIC,
1230 names.init,
1231 new MethodType(
1232 argtypes.append(
1233 accessConstructorTag().erasure(types)),
1234 constr.type.getReturnType(),
1235 constr.type.getThrownTypes(),
1236 syms.methodClass),
1237 accOwner);
1238 enterSynthetic(pos, aconstr, accOwner.members());
1239 accessConstrs.put(constr, aconstr);
1240 accessed.append(constr);
1241 }
1242 return aconstr;
1243 } else {
1244 return constr;
1245 }
1246 }
1247
1248 /** Return an anonymous class nested in this toplevel class.
1249 */
1250 ClassSymbol accessConstructorTag() {
1251 ClassSymbol topClass = currentClass.outermostClass();
1252 ModuleSymbol topModle = topClass.packge().modle;
1253 for (int i = 1; ; i++) {
1254 Name flatname = names.fromString("" + topClass.getQualifiedName() +
1255 target.syntheticNameChar() +
1256 i);
1257 ClassSymbol ctag = chk.getCompiled(topModle, flatname);
1258 if (ctag == null)
1259 // IDENTITY_TYPE will be interpreted as ACC_SUPER for older class files so we are fine
1260 ctag = makeEmptyClass(STATIC | SYNTHETIC | IDENTITY_TYPE, topClass).sym;
1261 else if (!ctag.isAnonymous())
1262 continue;
1263 // keep a record of all tags, to verify that all are generated as required
1264 accessConstrTags = accessConstrTags.prepend(ctag);
1265 return ctag;
1266 }
1267 }
1268
1269 /** Add all required access methods for a private symbol to enclosing class.
1270 * @param sym The symbol.
1271 */
1272 void makeAccessible(Symbol sym) {
1273 JCClassDecl cdef = classDef(sym.owner.enclClass());
1274 if (cdef == null) Assert.error("class def not found: " + sym + " in " + sym.owner);
1275 if (sym.name == names.init) {
1276 cdef.defs = cdef.defs.prepend(
1277 accessConstructorDef(cdef.pos, sym, accessConstrs.get(sym)));
1278 } else {
1279 MethodSymbol[] accessors = accessSyms.get(sym);
1280 for (int i = 0; i < AccessCode.numberOfAccessCodes; i++) {
1281 if (accessors[i] != null)
1282 cdef.defs = cdef.defs.prepend(
1283 accessDef(cdef.pos, sym, accessors[i], i));
1284 }
1285 }
1286 }
1287
1288 /** Construct definition of an access method.
1289 * @param pos The source code position of the definition.
1290 * @param vsym The private or protected symbol.
1291 * @param accessor The access method for the symbol.
1292 * @param acode The access code.
1293 */
1294 JCTree accessDef(int pos, Symbol vsym, MethodSymbol accessor, int acode) {
1295 // System.err.println("access " + vsym + " with " + accessor);//DEBUG
1296 currentClass = vsym.owner.enclClass();
1297 make.at(pos);
1298 JCMethodDecl md = make.MethodDef(accessor, null);
1299
1300 // Find actual symbol
1301 Symbol sym = actualSymbols.get(vsym);
1302 if (sym == null) sym = vsym;
1303
1304 JCExpression ref; // The tree referencing the private symbol.
1305 List<JCExpression> args; // Any additional arguments to be passed along.
1306 if ((sym.flags() & STATIC) != 0) {
1307 ref = make.Ident(sym);
1308 args = make.Idents(md.params);
1309 } else {
1310 JCExpression site = make.Ident(md.params.head);
1311 if (acode % 2 != 0) {
1312 //odd access codes represent qualified super accesses - need to
1313 //emit reference to the direct superclass, even if the referred
1314 //member is from an indirect superclass (JLS 13.1)
1315 site.setType(types.erasure(types.supertype(vsym.owner.enclClass().type)));
1316 }
1317 ref = make.Select(site, sym);
1318 args = make.Idents(md.params.tail);
1319 }
1320 JCStatement stat; // The statement accessing the private symbol.
1321 if (sym.kind == VAR) {
1322 // Normalize out all odd access codes by taking floor modulo 2:
1323 int acode1 = acode - (acode & 1);
1324
1325 JCExpression expr; // The access method's return value.
1326 AccessCode aCode = AccessCode.getFromCode(acode1);
1327 switch (aCode) {
1328 case DEREF:
1329 expr = ref;
1330 break;
1331 case ASSIGN:
1332 expr = make.Assign(ref, args.head);
1333 break;
1334 case PREINC: case POSTINC: case PREDEC: case POSTDEC:
1335 expr = makeUnary(aCode.tag, ref);
1336 break;
1337 default:
1338 expr = make.Assignop(
1339 treeTag(binaryAccessOperator(acode1, JCTree.Tag.NO_TAG)), ref, args.head);
1340 ((JCAssignOp) expr).operator = binaryAccessOperator(acode1, JCTree.Tag.NO_TAG);
1341 }
1342 stat = make.Return(expr.setType(sym.type));
1343 } else {
1344 stat = make.Call(make.App(ref, args));
1345 }
1346 md.body = make.Block(0, List.of(stat));
1347
1348 // Make sure all parameters, result types and thrown exceptions
1349 // are accessible.
1350 for (List<JCVariableDecl> l = md.params; l.nonEmpty(); l = l.tail)
1351 l.head.vartype = access(l.head.vartype);
1352 md.restype = access(md.restype);
1353 for (List<JCExpression> l = md.thrown; l.nonEmpty(); l = l.tail)
1354 l.head = access(l.head);
1355
1356 return md;
1357 }
1358
1359 /** Construct definition of an access constructor.
1360 * @param pos The source code position of the definition.
1361 * @param constr The private constructor.
1362 * @param accessor The access method for the constructor.
1363 */
1364 JCTree accessConstructorDef(int pos, Symbol constr, MethodSymbol accessor) {
1365 make.at(pos);
1366 JCMethodDecl md = make.MethodDef(accessor,
1367 accessor.externalType(types),
1368 null);
1369 JCIdent callee = make.Ident(names._this);
1370 callee.sym = constr;
1371 callee.type = constr.type;
1372 md.body =
1373 make.Block(0, List.of(
1374 make.Call(
1375 make.App(
1376 callee,
1377 make.Idents(md.params.reverse().tail.reverse())))));
1378 return md;
1379 }
1380
1381 /* ************************************************************************
1382 * Free variables proxies and this$n
1383 *************************************************************************/
1384
1385 /** A map which allows to retrieve the translated proxy variable for any given symbol of an
1386 * enclosing scope that is accessed (the accessed symbol could be the synthetic 'this$n' symbol).
1387 * Inside a constructor, the map temporarily overrides entries corresponding to proxies and any
1388 * 'this$n' symbols, where they represent the constructor parameters.
1389 */
1390 Map<Symbol, Symbol> proxies;
1391
1392 /** A scope containing all unnamed resource variables/saved
1393 * exception variables for translated TWR blocks
1394 */
1395 WriteableScope twrVars;
1396
1397 /** A stack containing the this$n field of the currently translated
1398 * classes (if needed) in innermost first order.
1399 * Inside a constructor, proxies and any this$n symbol are duplicated
1400 * in an additional innermost scope, where they represent the constructor
1401 * parameters.
1402 */
1403 List<VarSymbol> outerThisStack;
1404
1405 /** The name of a free variable proxy.
1406 */
1407 Name proxyName(Name name, int index) {
1408 Name proxyName = names.fromString("val" + target.syntheticNameChar() + name);
1409 if (index > 0) {
1410 proxyName = proxyName.append(names.fromString("" + target.syntheticNameChar() + index));
1411 }
1412 return proxyName;
1413 }
1414
1415 /** Proxy definitions for all free variables in given list, in reverse order.
1416 * @param pos The source code position of the definition.
1417 * @param freevars The free variables.
1418 * @param owner The class in which the definitions go.
1419 * @param additionalFlags Any additional flags
1420 */
1421 List<JCVariableDecl> freevarDefs(int pos, List<VarSymbol> freevars, Symbol owner) {
1422 return freevarDefs(pos, freevars, owner, LOCAL_CAPTURE_FIELD);
1423 }
1424
1425 List<JCVariableDecl> freevarDefs(int pos, List<VarSymbol> freevars, Symbol owner,
1426 long additionalFlags) {
1427 long flags = FINAL | SYNTHETIC | additionalFlags;
1428 List<JCVariableDecl> defs = List.nil();
1429 Set<Name> proxyNames = new HashSet<>();
1430 for (List<VarSymbol> l = freevars; l.nonEmpty(); l = l.tail) {
1431 VarSymbol v = l.head;
1432 int index = 0;
1433 Name proxyName;
1434 do {
1435 proxyName = proxyName(v.name, index++);
1436 } while (!proxyNames.add(proxyName));
1437 VarSymbol proxy = new VarSymbol(
1438 flags, proxyName, v.erasure(types), owner) {
1439 @Override
1440 public Symbol baseSymbol() {
1441 return v;
1442 }
1443 };
1444 proxies.put(v, proxy);
1445 JCVariableDecl vd = make.at(pos).VarDef(proxy, null);
1446 vd.vartype = access(vd.vartype);
1447 defs = defs.prepend(vd);
1448 }
1449 return defs;
1450 }
1451
1452 /** The name of a this$n field
1453 * @param type The class referenced by the this$n field
1454 */
1455 Name outerThisName(Type type, Symbol owner) {
1456 Type t = type.getEnclosingType();
1457 int nestingLevel = 0;
1458 while (t.hasTag(CLASS)) {
1459 t = t.getEnclosingType();
1460 nestingLevel++;
1461 }
1462 Name result = names.fromString("this" + target.syntheticNameChar() + nestingLevel);
1463 while (owner.kind == TYP && ((ClassSymbol)owner).members().findFirst(result) != null)
1464 result = names.fromString(result.toString() + target.syntheticNameChar());
1465 return result;
1466 }
1467
1468 private VarSymbol makeOuterThisVarSymbol(Symbol owner, long flags) {
1469 Type target = owner.innermostAccessibleEnclosingClass().erasure(types);
1470 // Set NOOUTERTHIS for all synthetic outer instance variables, and unset
1471 // it when the variable is accessed. If the variable is never accessed,
1472 // we skip creating an outer instance field and saving the constructor
1473 // parameter to it.
1474 VarSymbol outerThis =
1475 new VarSymbol(flags | NOOUTERTHIS, outerThisName(target, owner), target, owner);
1476 outerThisStack = outerThisStack.prepend(outerThis);
1477 return outerThis;
1478 }
1479
1480 private JCVariableDecl makeOuterThisVarDecl(int pos, VarSymbol sym) {
1481 JCVariableDecl vd = make.at(pos).VarDef(sym, null);
1482 vd.vartype = access(vd.vartype);
1483 return vd;
1484 }
1485
1486 /** Definition for this$n field.
1487 * @param pos The source code position of the definition.
1488 * @param owner The method in which the definition goes.
1489 */
1490 JCVariableDecl outerThisDef(int pos, MethodSymbol owner) {
1491 ClassSymbol c = owner.enclClass();
1492 boolean isMandated =
1493 // Anonymous constructors
1494 (owner.isConstructor() && owner.isAnonymous()) ||
1495 // Constructors of non-private inner member classes
1496 (owner.isConstructor() && c.isInner() &&
1497 !c.isPrivate() && !c.isStatic());
1498 long flags =
1499 FINAL | (isMandated ? MANDATED : SYNTHETIC) | PARAMETER;
1500 VarSymbol outerThis = makeOuterThisVarSymbol(owner, flags);
1501 owner.extraParams = owner.extraParams.prepend(outerThis);
1502 return makeOuterThisVarDecl(pos, outerThis);
1503 }
1504
1505 /** Definition for this$n field.
1506 * @param pos The source code position of the definition.
1507 * @param owner The class in which the definition goes.
1508 */
1509 JCVariableDecl outerThisDef(int pos, ClassSymbol owner) {
1510 VarSymbol outerThis = makeOuterThisVarSymbol(owner, FINAL | SYNTHETIC | (allowValueClasses && owner.isValueClass() ? STRICT : 0));
1511 return makeOuterThisVarDecl(pos, outerThis);
1512 }
1513
1514 /** Return a list of trees that load the free variables in given list,
1515 * in reverse order.
1516 * @param pos The source code position to be used for the trees.
1517 * @param freevars The list of free variables.
1518 */
1519 List<JCExpression> loadFreevars(DiagnosticPosition pos, List<VarSymbol> freevars) {
1520 List<JCExpression> args = List.nil();
1521 for (List<VarSymbol> l = freevars; l.nonEmpty(); l = l.tail)
1522 args = args.prepend(loadFreevar(pos, l.head));
1523 return args;
1524 }
1525 //where
1526 JCExpression loadFreevar(DiagnosticPosition pos, VarSymbol v) {
1527 return access(v, make.at(pos).Ident(v), null, false);
1528 }
1529
1530 /** Construct a tree simulating the expression {@code C.this}.
1531 * @param pos The source code position to be used for the tree.
1532 * @param c The qualifier class.
1533 */
1534 JCExpression makeThis(DiagnosticPosition pos, TypeSymbol c) {
1535 if (currentClass == c) {
1536 // in this case, `this' works fine
1537 return make.at(pos).This(c.erasure(types));
1538 } else {
1539 // need to go via this$n
1540 return makeOuterThis(pos, c);
1541 }
1542 }
1543
1544 /**
1545 * Optionally replace a try statement with the desugaring of a
1546 * try-with-resources statement. The canonical desugaring of
1547 *
1548 * try ResourceSpecification
1549 * Block
1550 *
1551 * is
1552 *
1553 * {
1554 * final VariableModifiers_minus_final R #resource = Expression;
1555 *
1556 * try ResourceSpecificationtail
1557 * Block
1558 * } body-only-finally {
1559 * if (#resource != null) //nullcheck skipped if Expression is provably non-null
1560 * #resource.close();
1561 * } catch (Throwable #primaryException) {
1562 * if (#resource != null) //nullcheck skipped if Expression is provably non-null
1563 * try {
1564 * #resource.close();
1565 * } catch (Throwable #suppressedException) {
1566 * #primaryException.addSuppressed(#suppressedException);
1567 * }
1568 * throw #primaryException;
1569 * }
1570 * }
1571 *
1572 * @param tree The try statement to inspect.
1573 * @return a desugared try-with-resources tree, or the original
1574 * try block if there are no resources to manage.
1575 */
1576 JCTree makeTwrTry(JCTry tree) {
1577 make_at(tree.pos());
1578 twrVars = twrVars.dup();
1579 JCBlock twrBlock = makeTwrBlock(tree.resources, tree.body, 0);
1580 if (tree.catchers.isEmpty() && tree.finalizer == null)
1581 result = translate(twrBlock);
1582 else
1583 result = translate(make.Try(twrBlock, tree.catchers, tree.finalizer));
1584 twrVars = twrVars.leave();
1585 return result;
1586 }
1587
1588 private JCBlock makeTwrBlock(List<JCTree> resources, JCBlock block, int depth) {
1589 if (resources.isEmpty())
1590 return block;
1591
1592 // Add resource declaration or expression to block statements
1593 ListBuffer<JCStatement> stats = new ListBuffer<>();
1594 JCTree resource = resources.head;
1595 JCExpression resourceUse;
1596 boolean resourceNonNull;
1597 if (resource instanceof JCVariableDecl variableDecl) {
1598 resourceUse = make.Ident(variableDecl.sym).setType(resource.type);
1599 resourceNonNull = variableDecl.init != null && TreeInfo.skipParens(variableDecl.init).hasTag(NEWCLASS);
1600 stats.add(variableDecl);
1601 } else {
1602 Assert.check(resource instanceof JCExpression);
1603 VarSymbol syntheticTwrVar =
1604 new VarSymbol(SYNTHETIC | FINAL,
1605 makeSyntheticName(names.fromString("twrVar" +
1606 depth), twrVars),
1607 (resource.type.hasTag(BOT)) ?
1608 syms.autoCloseableType : resource.type,
1609 currentMethodSym);
1610 twrVars.enter(syntheticTwrVar);
1611 JCVariableDecl syntheticTwrVarDecl =
1612 make.VarDef(syntheticTwrVar, (JCExpression)resource);
1613 resourceUse = (JCExpression)make.Ident(syntheticTwrVar);
1614 resourceNonNull = false;
1615 stats.add(syntheticTwrVarDecl);
1616 }
1617
1618 //create (semi-) finally block that will be copied into the main try body:
1619 int oldPos = make.pos;
1620 make.at(TreeInfo.endPos(block));
1621
1622 // if (#resource != null) { #resource.close(); }
1623 JCStatement bodyCloseStatement = makeResourceCloseInvocation(resourceUse);
1624
1625 if (!resourceNonNull) {
1626 bodyCloseStatement = make.If(makeNonNullCheck(resourceUse),
1627 bodyCloseStatement,
1628 null);
1629 }
1630
1631 JCBlock finallyClause = make.Block(BODY_ONLY_FINALIZE, List.of(bodyCloseStatement));
1632 make.at(oldPos);
1633
1634 // Create catch clause that saves exception, closes the resource and then rethrows the exception:
1635 VarSymbol primaryException =
1636 new VarSymbol(FINAL|SYNTHETIC,
1637 names.fromString("t" +
1638 target.syntheticNameChar()),
1639 syms.throwableType,
1640 currentMethodSym);
1641 JCVariableDecl primaryExceptionDecl = make.VarDef(primaryException, null);
1642
1643 // close resource:
1644 // try {
1645 // #resource.close();
1646 // } catch (Throwable #suppressedException) {
1647 // #primaryException.addSuppressed(#suppressedException);
1648 // }
1649 VarSymbol suppressedException =
1650 new VarSymbol(SYNTHETIC, make.paramName(2),
1651 syms.throwableType,
1652 currentMethodSym);
1653 JCStatement addSuppressedStatement =
1654 make.Exec(makeCall(make.Ident(primaryException),
1655 names.addSuppressed,
1656 List.of(make.Ident(suppressedException))));
1657 JCBlock closeResourceTryBlock =
1658 make.Block(0L, List.of(makeResourceCloseInvocation(resourceUse)));
1659 JCVariableDecl catchSuppressedDecl = make.VarDef(suppressedException, null);
1660 JCBlock catchSuppressedBlock = make.Block(0L, List.of(addSuppressedStatement));
1661 List<JCCatch> catchSuppressedClauses =
1662 List.of(make.Catch(catchSuppressedDecl, catchSuppressedBlock));
1663 JCTry closeResourceTry = make.Try(closeResourceTryBlock, catchSuppressedClauses, null);
1664 closeResourceTry.finallyCanCompleteNormally = true;
1665
1666 JCStatement exceptionalCloseStatement = closeResourceTry;
1667
1668 if (!resourceNonNull) {
1669 // if (#resource != null) { }
1670 exceptionalCloseStatement = make.If(makeNonNullCheck(resourceUse),
1671 exceptionalCloseStatement,
1672 null);
1673 }
1674
1675 JCStatement exceptionalRethrow = make.Throw(make.Ident(primaryException));
1676 JCBlock exceptionalCloseBlock = make.Block(0L, List.of(exceptionalCloseStatement, exceptionalRethrow));
1677 JCCatch exceptionalCatchClause = make.Catch(primaryExceptionDecl, exceptionalCloseBlock);
1678
1679 //create the main try statement with the close:
1680 JCTry outerTry = make.Try(makeTwrBlock(resources.tail, block, depth + 1),
1681 List.of(exceptionalCatchClause),
1682 finallyClause);
1683
1684 outerTry.finallyCanCompleteNormally = true;
1685 stats.add(outerTry);
1686
1687 JCBlock newBlock = make.Block(0L, stats.toList());
1688 return newBlock;
1689 }
1690
1691 private JCStatement makeResourceCloseInvocation(JCExpression resource) {
1692 // convert to AutoCloseable if needed
1693 if (types.asSuper(resource.type, syms.autoCloseableType.tsym) == null) {
1694 resource = convert(resource, syms.autoCloseableType);
1695 }
1696
1697 // create resource.close() method invocation
1698 JCExpression resourceClose = makeCall(resource,
1699 names.close,
1700 List.nil());
1701 return make.Exec(resourceClose);
1702 }
1703
1704 private JCExpression makeNonNullCheck(JCExpression expression) {
1705 return makeBinary(NE, expression, makeNull());
1706 }
1707
1708 /** Construct a tree that represents the outer instance
1709 * {@code C.this}. Never pick the current `this'.
1710 * @param pos The source code position to be used for the tree.
1711 * @param c The qualifier class.
1712 */
1713 JCExpression makeOuterThis(DiagnosticPosition pos, TypeSymbol c) {
1714 List<VarSymbol> ots = outerThisStack;
1715 if (ots.isEmpty()) {
1716 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1717 return makeNull();
1718 }
1719 VarSymbol ot = ots.head;
1720 JCExpression tree = access(make.at(pos).Ident(ot));
1721 ot.flags_field &= ~NOOUTERTHIS;
1722 TypeSymbol otc = ot.type.tsym;
1723 while (otc != c) {
1724 do {
1725 ots = ots.tail;
1726 if (ots.isEmpty()) {
1727 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1728 Assert.error(); // should have been caught in Attr
1729 return tree;
1730 }
1731 ot = ots.head;
1732 } while (ot.owner != otc);
1733 if (otc.owner.kind != PCK && !otc.hasOuterInstance()) {
1734 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1735 Assert.error(); // should have been caught in Attr
1736 return makeNull();
1737 }
1738 tree = access(make.at(pos).Select(tree, ot));
1739 ot.flags_field &= ~NOOUTERTHIS;
1740 otc = ot.type.tsym;
1741 }
1742 return tree;
1743 }
1744
1745 /** Construct a tree that represents the closest outer instance
1746 * {@code C.this} such that the given symbol is a member of C.
1747 * @param pos The source code position to be used for the tree.
1748 * @param sym The accessed symbol.
1749 * @param preciseMatch should we accept a type that is a subtype of
1750 * sym's owner, even if it doesn't contain sym
1751 * due to hiding, overriding, or non-inheritance
1752 * due to protection?
1753 */
1754 JCExpression makeOwnerThis(DiagnosticPosition pos, Symbol sym, boolean preciseMatch) {
1755 if (preciseMatch ? sym.isMemberOf(currentClass, types)
1756 : currentClass.isSubClass(sym.owner, types)) {
1757 // in this case, `this' works fine
1758 return make.at(pos).This(currentClass.erasure(types));
1759 } else {
1760 // need to go via this$n
1761 return makeOwnerThisN(pos, sym, preciseMatch);
1762 }
1763 }
1764
1765 /**
1766 * Similar to makeOwnerThis but will never pick "this".
1767 */
1768 JCExpression makeOwnerThisN(DiagnosticPosition pos, Symbol sym, boolean preciseMatch) {
1769 Symbol c = sym.owner;
1770 List<VarSymbol> ots = outerThisStack;
1771 if (ots.isEmpty()) {
1772 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1773 return makeNull();
1774 }
1775 VarSymbol ot = ots.head;
1776 JCExpression tree = access(make.at(pos).Ident(ot));
1777 ot.flags_field &= ~NOOUTERTHIS;
1778 TypeSymbol otc = ot.type.tsym;
1779 while (!(preciseMatch ? sym.isMemberOf(otc, types) : otc.isSubClass(sym.owner, types))) {
1780 do {
1781 ots = ots.tail;
1782 if (ots.isEmpty()) {
1783 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1784 return tree;
1785 }
1786 ot = ots.head;
1787 } while (ot.owner != otc);
1788 tree = access(make.at(pos).Select(tree, ot));
1789 ot.flags_field &= ~NOOUTERTHIS;
1790 otc = ot.type.tsym;
1791 }
1792 return tree;
1793 }
1794
1795 /** Return tree simulating the assignment {@code this.name = name}, where
1796 * name is the name of a free variable.
1797 */
1798 JCStatement initField(int pos, Symbol rhs, Symbol lhs) {
1799 Assert.check(rhs.owner.kind == MTH);
1800 Assert.check(rhs.owner.owner == lhs.owner);
1801 make.at(pos);
1802 return
1803 make.Exec(
1804 make.Assign(
1805 make.Select(make.This(lhs.owner.erasure(types)), lhs),
1806 make.Ident(rhs)).setType(lhs.erasure(types)));
1807 }
1808
1809 /**
1810 * Return tree simulating null checking outer this and/or assigning. This is
1811 * called when a null check is required (nullCheckOuterThis), or a synthetic
1812 * field is generated (stores).
1813 */
1814 JCStatement initOuterThis(int pos, VarSymbol rhs, boolean stores) {
1815 Assert.check(rhs.owner.kind == MTH);
1816 Assert.check(nullCheckOuterThis || stores); // One of the flags must be true
1817 make.at(pos);
1818 JCExpression expression = make.Ident(rhs);
1819 if (nullCheckOuterThis) {
1820 expression = attr.makeNullCheck(expression);
1821 }
1822 if (stores) {
1823 VarSymbol lhs = outerThisStack.head;
1824 Assert.check(rhs.owner.owner == lhs.owner);
1825 expression = make.Assign(
1826 make.Select(make.This(lhs.owner.erasure(types)), lhs),
1827 expression).setType(lhs.erasure(types));
1828 }
1829 return make.Exec(expression);
1830 }
1831
1832 /* ************************************************************************
1833 * Code for .class
1834 *************************************************************************/
1835
1836 /** Return the symbol of a class to contain a cache of
1837 * compiler-generated statics such as class$ and the
1838 * $assertionsDisabled flag. We create an anonymous nested class
1839 * (unless one already exists) and return its symbol. However,
1840 * for backward compatibility in 1.4 and earlier we use the
1841 * top-level class itself.
1842 */
1843 private ClassSymbol outerCacheClass() {
1844 ClassSymbol clazz = outermostClassDef.sym;
1845 Scope s = clazz.members();
1846 for (Symbol sym : s.getSymbols(NON_RECURSIVE))
1847 if (sym.kind == TYP &&
1848 sym.name == names.empty &&
1849 (sym.flags() & INTERFACE) == 0) return (ClassSymbol) sym;
1850 // IDENTITY_TYPE will be interpreted as ACC_SUPER for older class files so we are fine
1851 return makeEmptyClass(STATIC | SYNTHETIC | IDENTITY_TYPE, clazz).sym;
1852 }
1853
1854 /** Create an attributed tree of the form left.name(). */
1855 private JCMethodInvocation makeCall(JCExpression left, Name name, List<JCExpression> args) {
1856 Assert.checkNonNull(left.type);
1857 Symbol funcsym = lookupMethod(make_pos, name, left.type,
1858 TreeInfo.types(args));
1859 return make.App(make.Select(left, funcsym), args);
1860 }
1861
1862 /** The tree simulating a T.class expression.
1863 * @param clazz The tree identifying type T.
1864 */
1865 private JCExpression classOf(JCTree clazz) {
1866 return classOfType(clazz.type, clazz.pos());
1867 }
1868
1869 private JCExpression classOfType(Type type, DiagnosticPosition pos) {
1870 switch (type.getTag()) {
1871 case BYTE: case SHORT: case CHAR: case INT: case LONG: case FLOAT:
1872 case DOUBLE: case BOOLEAN: case VOID:
1873 // replace with <BoxedClass>.TYPE
1874 ClassSymbol c = types.boxedClass(type);
1875 Symbol typeSym =
1876 rs.accessBase(
1877 rs.findIdentInType(pos, attrEnv, c.type, names.TYPE, KindSelector.VAR),
1878 pos, c.type, names.TYPE, true);
1879 if (typeSym.kind == VAR)
1880 ((VarSymbol)typeSym).getConstValue(); // ensure initializer is evaluated
1881 return make.QualIdent(typeSym);
1882 case CLASS: case ARRAY:
1883 VarSymbol sym = new VarSymbol(
1884 STATIC | PUBLIC | FINAL, names._class,
1885 syms.classType, type.tsym);
1886 return make_at(pos).Select(make.Type(type), sym);
1887 default:
1888 throw new AssertionError();
1889 }
1890 }
1891
1892 /* ************************************************************************
1893 * Code for enabling/disabling assertions.
1894 *************************************************************************/
1895
1896 private ClassSymbol assertionsDisabledClassCache;
1897
1898 /**Used to create an auxiliary class to hold $assertionsDisabled for interfaces.
1899 */
1900 private ClassSymbol assertionsDisabledClass() {
1901 if (assertionsDisabledClassCache != null) return assertionsDisabledClassCache;
1902
1903 // IDENTITY_TYPE will be interpreted as ACC_SUPER for older class files so we are fine
1904 assertionsDisabledClassCache = makeEmptyClass(STATIC | SYNTHETIC | IDENTITY_TYPE, outermostClassDef.sym).sym;
1905
1906 return assertionsDisabledClassCache;
1907 }
1908
1909 // This code is not particularly robust if the user has
1910 // previously declared a member named '$assertionsDisabled'.
1911 // The same faulty idiom also appears in the translation of
1912 // class literals above. We should report an error if a
1913 // previous declaration is not synthetic.
1914
1915 private JCExpression assertFlagTest(DiagnosticPosition pos) {
1916 // Outermost class may be either true class or an interface.
1917 ClassSymbol outermostClass = outermostClassDef.sym;
1918
1919 //only classes can hold a non-public field, look for a usable one:
1920 ClassSymbol container = !currentClass.isInterface() ? currentClass :
1921 assertionsDisabledClass();
1922
1923 VarSymbol assertDisabledSym =
1924 (VarSymbol)lookupSynthetic(dollarAssertionsDisabled,
1925 container.members());
1926 if (assertDisabledSym == null) {
1927 assertDisabledSym =
1928 new VarSymbol(STATIC | FINAL | SYNTHETIC,
1929 dollarAssertionsDisabled,
1930 syms.booleanType,
1931 container);
1932 enterSynthetic(pos, assertDisabledSym, container.members());
1933 Symbol desiredAssertionStatusSym = lookupMethod(pos,
1934 names.desiredAssertionStatus,
1935 types.erasure(syms.classType),
1936 List.nil());
1937 JCClassDecl containerDef = classDef(container);
1938 make_at(containerDef.pos());
1939 JCExpression notStatus = makeUnary(NOT, make.App(make.Select(
1940 classOfType(types.erasure(outermostClass.type),
1941 containerDef.pos()),
1942 desiredAssertionStatusSym)));
1943 JCVariableDecl assertDisabledDef = make.VarDef(assertDisabledSym,
1944 notStatus);
1945 containerDef.defs = containerDef.defs.prepend(assertDisabledDef);
1946
1947 if (currentClass.isInterface()) {
1948 //need to load the assertions enabled/disabled state while
1949 //initializing the interface:
1950 JCClassDecl currentClassDef = classDef(currentClass);
1951 make_at(currentClassDef.pos());
1952 JCStatement dummy = make.If(make.QualIdent(assertDisabledSym), make.Skip(), null);
1953 JCBlock clinit = make.Block(STATIC, List.of(dummy));
1954 currentClassDef.defs = currentClassDef.defs.prepend(clinit);
1955 }
1956 }
1957 make_at(pos);
1958 return makeUnary(NOT, make.Ident(assertDisabledSym));
1959 }
1960
1961
1962 /* ************************************************************************
1963 * Building blocks for let expressions
1964 *************************************************************************/
1965
1966 interface TreeBuilder {
1967 JCExpression build(JCExpression arg);
1968 }
1969
1970 /** Construct an expression using the builder, with the given rval
1971 * expression as an argument to the builder. However, the rval
1972 * expression must be computed only once, even if used multiple
1973 * times in the result of the builder. We do that by
1974 * constructing a "let" expression that saves the rvalue into a
1975 * temporary variable and then uses the temporary variable in
1976 * place of the expression built by the builder. The complete
1977 * resulting expression is of the form
1978 * <pre>
1979 * (let <b>TYPE</b> <b>TEMP</b> = <b>RVAL</b>;
1980 * in (<b>BUILDER</b>(<b>TEMP</b>)))
1981 * </pre>
1982 * where <code><b>TEMP</b></code> is a newly declared variable
1983 * in the let expression.
1984 */
1985 JCExpression abstractRval(JCExpression rval, Type type, TreeBuilder builder) {
1986 rval = TreeInfo.skipParens(rval);
1987 switch (rval.getTag()) {
1988 case LITERAL:
1989 return builder.build(rval);
1990 case IDENT:
1991 JCIdent id = (JCIdent) rval;
1992 if ((id.sym.flags() & FINAL) != 0 && id.sym.owner.kind == MTH)
1993 return builder.build(rval);
1994 }
1995 Name name = TreeInfo.name(rval);
1996 if (name == names._super || name == names._this)
1997 return builder.build(rval);
1998 VarSymbol var =
1999 new VarSymbol(FINAL|SYNTHETIC,
2000 names.fromString(
2001 target.syntheticNameChar()
2002 + "" + rval.hashCode()),
2003 type,
2004 currentMethodSym);
2005 rval = convert(rval,type);
2006 JCVariableDecl def = make.VarDef(var, rval); // XXX cast
2007 JCExpression built = builder.build(make.Ident(var));
2008 JCExpression res = make.LetExpr(def, built);
2009 res.type = built.type;
2010 return res;
2011 }
2012
2013 // same as above, with the type of the temporary variable computed
2014 JCExpression abstractRval(JCExpression rval, TreeBuilder builder) {
2015 return abstractRval(rval, rval.type, builder);
2016 }
2017
2018 // same as above, but for an expression that may be used as either
2019 // an rvalue or an lvalue. This requires special handling for
2020 // Select expressions, where we place the left-hand-side of the
2021 // select in a temporary, and for Indexed expressions, where we
2022 // place both the indexed expression and the index value in temps.
2023 JCExpression abstractLval(JCExpression lval, final TreeBuilder builder) {
2024 lval = TreeInfo.skipParens(lval);
2025 switch (lval.getTag()) {
2026 case IDENT:
2027 return builder.build(lval);
2028 case SELECT: {
2029 final JCFieldAccess s = (JCFieldAccess)lval;
2030 Symbol lid = TreeInfo.symbol(s.selected);
2031 if (lid != null && lid.kind == TYP) return builder.build(lval);
2032 return abstractRval(s.selected, selected -> builder.build(make.Select(selected, s.sym)));
2033 }
2034 case INDEXED: {
2035 final JCArrayAccess i = (JCArrayAccess)lval;
2036 return abstractRval(i.indexed, indexed -> abstractRval(i.index, syms.intType, index -> {
2037 JCExpression newLval = make.Indexed(indexed, index);
2038 newLval.setType(i.type);
2039 return builder.build(newLval);
2040 }));
2041 }
2042 case TYPECAST: {
2043 return abstractLval(((JCTypeCast)lval).expr, builder);
2044 }
2045 }
2046 throw new AssertionError(lval);
2047 }
2048
2049 // evaluate and discard the first expression, then evaluate the second.
2050 JCExpression makeComma(final JCExpression expr1, final JCExpression expr2) {
2051 JCExpression res = make.LetExpr(List.of(make.Exec(expr1)), expr2);
2052 res.type = expr2.type;
2053 return res;
2054 }
2055
2056 /* ************************************************************************
2057 * Translation methods
2058 *************************************************************************/
2059
2060 /** Visitor argument: enclosing operator node.
2061 */
2062 private JCExpression enclOp;
2063
2064 /** Visitor method: Translate a single node.
2065 * Attach the source position from the old tree to its replacement tree.
2066 */
2067 @Override
2068 public <T extends JCTree> T translate(T tree) {
2069 if (tree == null) {
2070 return null;
2071 } else {
2072 make_at(tree.pos());
2073 T result = super.translate(tree);
2074 if (endPosTable != null && result != tree) {
2075 endPosTable.replaceTree(tree, result);
2076 }
2077 return result;
2078 }
2079 }
2080
2081 /** Visitor method: Translate a single node, boxing or unboxing if needed.
2082 */
2083 public <T extends JCExpression> T translate(T tree, Type type) {
2084 return (tree == null) ? null : boxIfNeeded(translate(tree), type);
2085 }
2086
2087 /** Visitor method: Translate tree.
2088 */
2089 public <T extends JCTree> T translate(T tree, JCExpression enclOp) {
2090 JCExpression prevEnclOp = this.enclOp;
2091 this.enclOp = enclOp;
2092 T res = translate(tree);
2093 this.enclOp = prevEnclOp;
2094 return res;
2095 }
2096
2097 /** Visitor method: Translate list of trees.
2098 */
2099 public <T extends JCExpression> List<T> translate(List<T> trees, Type type) {
2100 if (trees == null) return null;
2101 for (List<T> l = trees; l.nonEmpty(); l = l.tail)
2102 l.head = translate(l.head, type);
2103 return trees;
2104 }
2105
2106 public void visitPackageDef(JCPackageDecl tree) {
2107 if (!needPackageInfoClass(tree))
2108 return;
2109
2110 long flags = Flags.ABSTRACT | Flags.INTERFACE;
2111 // package-info is marked SYNTHETIC in JDK 1.6 and later releases
2112 flags = flags | Flags.SYNTHETIC;
2113 ClassSymbol c = tree.packge.package_info;
2114 c.setAttributes(tree.packge);
2115 c.flags_field |= flags;
2116 ClassType ctype = (ClassType) c.type;
2117 ctype.supertype_field = syms.objectType;
2118 ctype.interfaces_field = List.nil();
2119 createInfoClass(tree.annotations, c);
2120 }
2121 // where
2122 private boolean needPackageInfoClass(JCPackageDecl pd) {
2123 switch (pkginfoOpt) {
2124 case ALWAYS:
2125 return true;
2126 case LEGACY:
2127 return pd.getAnnotations().nonEmpty();
2128 case NONEMPTY:
2129 for (Attribute.Compound a :
2130 pd.packge.getDeclarationAttributes()) {
2131 Attribute.RetentionPolicy p = types.getRetention(a);
2132 if (p != Attribute.RetentionPolicy.SOURCE)
2133 return true;
2134 }
2135 return false;
2136 }
2137 throw new AssertionError();
2138 }
2139
2140 public void visitModuleDef(JCModuleDecl tree) {
2141 ModuleSymbol msym = tree.sym;
2142 ClassSymbol c = msym.module_info;
2143 c.setAttributes(msym);
2144 c.flags_field |= Flags.MODULE;
2145 createInfoClass(List.nil(), tree.sym.module_info);
2146 }
2147
2148 private void createInfoClass(List<JCAnnotation> annots, ClassSymbol c) {
2149 long flags = Flags.ABSTRACT | Flags.INTERFACE;
2150 JCClassDecl infoClass =
2151 make.ClassDef(make.Modifiers(flags, annots),
2152 c.name, List.nil(),
2153 null, List.nil(), List.nil());
2154 infoClass.sym = c;
2155 translated.append(infoClass);
2156 }
2157
2158 public void visitClassDef(JCClassDecl tree) {
2159 Env<AttrContext> prevEnv = attrEnv;
2160 ClassSymbol currentClassPrev = currentClass;
2161 MethodSymbol currentMethodSymPrev = currentMethodSym;
2162
2163 currentClass = tree.sym;
2164 currentMethodSym = null;
2165 attrEnv = typeEnvs.remove(currentClass);
2166 if (attrEnv == null)
2167 attrEnv = prevEnv;
2168
2169 classdefs.put(currentClass, tree);
2170
2171 Map<Symbol, Symbol> prevProxies = proxies;
2172 proxies = new HashMap<>(proxies);
2173 List<VarSymbol> prevOuterThisStack = outerThisStack;
2174
2175 // If this is an enum definition
2176 if ((tree.mods.flags & ENUM) != 0 &&
2177 (types.supertype(currentClass.type).tsym.flags() & ENUM) == 0)
2178 visitEnumDef(tree);
2179
2180 if ((tree.mods.flags & RECORD) != 0) {
2181 visitRecordDef(tree);
2182 }
2183
2184 // If this is a nested class, define a this$n field for
2185 // it and add to proxies.
2186 JCVariableDecl otdef = null;
2187 if (currentClass.hasOuterInstance())
2188 otdef = outerThisDef(tree.pos, currentClass);
2189
2190 // If this is a local class, define proxies for all its free variables.
2191 List<JCVariableDecl> fvdefs = freevarDefs(
2192 tree.pos, freevars(currentClass), currentClass, allowValueClasses && currentClass.isValueClass() ? STRICT : LOCAL_CAPTURE_FIELD);
2193
2194 // Recursively translate superclass, interfaces.
2195 tree.extending = translate(tree.extending);
2196 tree.implementing = translate(tree.implementing);
2197
2198 if (currentClass.isDirectlyOrIndirectlyLocal()) {
2199 ClassSymbol encl = currentClass.owner.enclClass();
2200 if (encl.trans_local == null) {
2201 encl.trans_local = List.nil();
2202 }
2203 encl.trans_local = encl.trans_local.prepend(currentClass);
2204 }
2205
2206 // Recursively translate members, taking into account that new members
2207 // might be created during the translation and prepended to the member
2208 // list `tree.defs'.
2209 List<JCTree> seen = List.nil();
2210 while (tree.defs != seen) {
2211 List<JCTree> unseen = tree.defs;
2212 for (List<JCTree> l = unseen; l.nonEmpty() && l != seen; l = l.tail) {
2213 JCTree outermostMemberDefPrev = outermostMemberDef;
2214 if (outermostMemberDefPrev == null) outermostMemberDef = l.head;
2215 l.head = translate(l.head);
2216 outermostMemberDef = outermostMemberDefPrev;
2217 }
2218 seen = unseen;
2219 }
2220
2221 // Convert a protected modifier to public, mask static modifier.
2222 if ((tree.mods.flags & PROTECTED) != 0) tree.mods.flags |= PUBLIC;
2223 tree.mods.flags &= ClassFlags;
2224
2225 // Convert name to flat representation, replacing '.' by '$'.
2226 tree.name = Convert.shortName(currentClass.flatName());
2227
2228 // Add free variables proxy definitions to class.
2229
2230 for (List<JCVariableDecl> l = fvdefs; l.nonEmpty(); l = l.tail) {
2231 tree.defs = tree.defs.prepend(l.head);
2232 enterSynthetic(tree.pos(), l.head.sym, currentClass.members());
2233 }
2234 // If this$n was accessed, add the field definition and prepend
2235 // initializer code to any super() invocation to initialize it
2236 // otherwise prepend enclosing instance null check code if required
2237 emitOuter:
2238 if (currentClass.hasOuterInstance()) {
2239 boolean storesThis = shouldEmitOuterThis(currentClass);
2240 if (storesThis) {
2241 tree.defs = tree.defs.prepend(otdef);
2242 enterSynthetic(tree.pos(), otdef.sym, currentClass.members());
2243 } else if (!nullCheckOuterThis) {
2244 break emitOuter;
2245 }
2246
2247 for (JCTree def : tree.defs) {
2248 if (TreeInfo.isConstructor(def)) {
2249 JCMethodDecl mdef = (JCMethodDecl)def;
2250 if (TreeInfo.hasConstructorCall(mdef, names._super)) {
2251 List<JCStatement> initializer = List.of(initOuterThis(mdef.body.pos, mdef.params.head.sym, storesThis)) ;
2252 TreeInfo.mapSuperCalls(mdef.body, supercall -> make.Block(0, initializer.append(supercall)));
2253 }
2254 }
2255 }
2256 }
2257
2258 proxies = prevProxies;
2259 outerThisStack = prevOuterThisStack;
2260
2261 // Append translated tree to `translated' queue.
2262 translated.append(tree);
2263
2264 attrEnv = prevEnv;
2265 currentClass = currentClassPrev;
2266 currentMethodSym = currentMethodSymPrev;
2267
2268 // Return empty block {} as a placeholder for an inner class.
2269 result = make_at(tree.pos()).Block(SYNTHETIC, List.nil());
2270 }
2271
2272 private boolean shouldEmitOuterThis(ClassSymbol sym) {
2273 if (!optimizeOuterThis) {
2274 // Optimization is disabled
2275 return true;
2276 }
2277 if ((outerThisStack.head.flags_field & NOOUTERTHIS) == 0) {
2278 // Enclosing instance field is used
2279 return true;
2280 }
2281 if (rs.isSerializable(sym.type)) {
2282 // Class is serializable
2283 return true;
2284 }
2285 return false;
2286 }
2287
2288 List<JCTree> generateMandatedAccessors(JCClassDecl tree) {
2289 List<JCVariableDecl> fields = TreeInfo.recordFields(tree);
2290 return tree.sym.getRecordComponents().stream()
2291 .filter(rc -> (rc.accessor.flags() & Flags.GENERATED_MEMBER) != 0)
2292 .map(rc -> {
2293 // we need to return the field not the record component
2294 JCVariableDecl field = fields.stream().filter(f -> f.name == rc.name).findAny().get();
2295 make_at(tree.pos());
2296 return make.MethodDef(rc.accessor, make.Block(0,
2297 List.of(make.Return(make.Ident(field)))));
2298 }).collect(List.collector());
2299 }
2300
2301 /** Translate an enum class. */
2302 private void visitEnumDef(JCClassDecl tree) {
2303 make_at(tree.pos());
2304
2305 // add the supertype, if needed
2306 if (tree.extending == null)
2307 tree.extending = make.Type(types.supertype(tree.type));
2308
2309 // classOfType adds a cache field to tree.defs
2310 JCExpression e_class = classOfType(tree.sym.type, tree.pos()).
2311 setType(types.erasure(syms.classType));
2312
2313 // process each enumeration constant, adding implicit constructor parameters
2314 int nextOrdinal = 0;
2315 ListBuffer<JCExpression> values = new ListBuffer<>();
2316 ListBuffer<JCTree> enumDefs = new ListBuffer<>();
2317 ListBuffer<JCTree> otherDefs = new ListBuffer<>();
2318 for (List<JCTree> defs = tree.defs;
2319 defs.nonEmpty();
2320 defs=defs.tail) {
2321 if (defs.head.hasTag(VARDEF) && (((JCVariableDecl) defs.head).mods.flags & ENUM) != 0) {
2322 JCVariableDecl var = (JCVariableDecl)defs.head;
2323 visitEnumConstantDef(var, nextOrdinal++);
2324 values.append(make.QualIdent(var.sym));
2325 enumDefs.append(var);
2326 } else {
2327 otherDefs.append(defs.head);
2328 }
2329 }
2330
2331 // synthetic private static T[] $values() { return new T[] { a, b, c }; }
2332 // synthetic private static final T[] $VALUES = $values();
2333 Name valuesName = syntheticName(tree, "VALUES");
2334 Type arrayType = new ArrayType(types.erasure(tree.type), syms.arrayClass);
2335 VarSymbol valuesVar = new VarSymbol(PRIVATE|FINAL|STATIC|SYNTHETIC,
2336 valuesName,
2337 arrayType,
2338 tree.type.tsym);
2339 JCNewArray newArray = make.NewArray(make.Type(types.erasure(tree.type)),
2340 List.nil(),
2341 values.toList());
2342 newArray.type = arrayType;
2343
2344 MethodSymbol valuesMethod = new MethodSymbol(PRIVATE|STATIC|SYNTHETIC,
2345 syntheticName(tree, "values"),
2346 new MethodType(List.nil(), arrayType, List.nil(), tree.type.tsym),
2347 tree.type.tsym);
2348 enumDefs.append(make.MethodDef(valuesMethod, make.Block(0, List.of(make.Return(newArray)))));
2349 tree.sym.members().enter(valuesMethod);
2350
2351 enumDefs.append(make.VarDef(valuesVar, make.App(make.QualIdent(valuesMethod))));
2352 tree.sym.members().enter(valuesVar);
2353
2354 MethodSymbol valuesSym = lookupMethod(tree.pos(), names.values,
2355 tree.type, List.nil());
2356 List<JCStatement> valuesBody;
2357 if (useClone()) {
2358 // return (T[]) $VALUES.clone();
2359 JCTypeCast valuesResult =
2360 make.TypeCast(valuesSym.type.getReturnType(),
2361 make.App(make.Select(make.Ident(valuesVar),
2362 syms.arrayCloneMethod)));
2363 valuesBody = List.of(make.Return(valuesResult));
2364 } else {
2365 // template: T[] $result = new T[$values.length];
2366 Name resultName = syntheticName(tree, "result");
2367 VarSymbol resultVar = new VarSymbol(FINAL|SYNTHETIC,
2368 resultName,
2369 arrayType,
2370 valuesSym);
2371 JCNewArray resultArray = make.NewArray(make.Type(types.erasure(tree.type)),
2372 List.of(make.Select(make.Ident(valuesVar), syms.lengthVar)),
2373 null);
2374 resultArray.type = arrayType;
2375 JCVariableDecl decl = make.VarDef(resultVar, resultArray);
2376
2377 // template: System.arraycopy($VALUES, 0, $result, 0, $VALUES.length);
2378 if (systemArraycopyMethod == null) {
2379 systemArraycopyMethod =
2380 new MethodSymbol(PUBLIC | STATIC,
2381 names.fromString("arraycopy"),
2382 new MethodType(List.of(syms.objectType,
2383 syms.intType,
2384 syms.objectType,
2385 syms.intType,
2386 syms.intType),
2387 syms.voidType,
2388 List.nil(),
2389 syms.methodClass),
2390 syms.systemType.tsym);
2391 }
2392 JCStatement copy =
2393 make.Exec(make.App(make.Select(make.Ident(syms.systemType.tsym),
2394 systemArraycopyMethod),
2395 List.of(make.Ident(valuesVar), make.Literal(0),
2396 make.Ident(resultVar), make.Literal(0),
2397 make.Select(make.Ident(valuesVar), syms.lengthVar))));
2398
2399 // template: return $result;
2400 JCStatement ret = make.Return(make.Ident(resultVar));
2401 valuesBody = List.of(decl, copy, ret);
2402 }
2403
2404 JCMethodDecl valuesDef =
2405 make.MethodDef(valuesSym, make.Block(0, valuesBody));
2406
2407 enumDefs.append(valuesDef);
2408
2409 if (debugLower)
2410 System.err.println(tree.sym + ".valuesDef = " + valuesDef);
2411
2412 /** The template for the following code is:
2413 *
2414 * public static E valueOf(String name) {
2415 * return (E)Enum.valueOf(E.class, name);
2416 * }
2417 *
2418 * where E is tree.sym
2419 */
2420 MethodSymbol valueOfSym = lookupMethod(tree.pos(),
2421 names.valueOf,
2422 tree.sym.type,
2423 List.of(syms.stringType));
2424 Assert.check((valueOfSym.flags() & STATIC) != 0);
2425 VarSymbol nameArgSym = valueOfSym.params.head;
2426 JCIdent nameVal = make.Ident(nameArgSym);
2427 JCStatement enum_ValueOf =
2428 make.Return(make.TypeCast(tree.sym.type,
2429 makeCall(make.Ident(syms.enumSym),
2430 names.valueOf,
2431 List.of(e_class, nameVal))));
2432 JCMethodDecl valueOf = make.MethodDef(valueOfSym,
2433 make.Block(0, List.of(enum_ValueOf)));
2434 nameVal.sym = valueOf.params.head.sym;
2435 if (debugLower)
2436 System.err.println(tree.sym + ".valueOf = " + valueOf);
2437 enumDefs.append(valueOf);
2438
2439 enumDefs.appendList(otherDefs.toList());
2440 tree.defs = enumDefs.toList();
2441 }
2442 // where
2443 private MethodSymbol systemArraycopyMethod;
2444 private boolean useClone() {
2445 try {
2446 return syms.objectType.tsym.members().findFirst(names.clone) != null;
2447 }
2448 catch (CompletionFailure e) {
2449 return false;
2450 }
2451 }
2452
2453 private Name syntheticName(JCClassDecl tree, String baseName) {
2454 Name valuesName = names.fromString(target.syntheticNameChar() + baseName);
2455 while (tree.sym.members().findFirst(valuesName) != null) // avoid name clash
2456 valuesName = names.fromString(valuesName + "" + target.syntheticNameChar());
2457 return valuesName;
2458 }
2459
2460 /** Translate an enumeration constant and its initializer. */
2461 private void visitEnumConstantDef(JCVariableDecl var, int ordinal) {
2462 JCNewClass varDef = (JCNewClass)var.init;
2463 varDef.args = varDef.args.
2464 prepend(makeLit(syms.intType, ordinal)).
2465 prepend(makeLit(syms.stringType, var.name.toString()));
2466 }
2467
2468 private List<VarSymbol> recordVars(Type t) {
2469 List<VarSymbol> vars = List.nil();
2470 while (!t.hasTag(NONE)) {
2471 if (t.hasTag(CLASS)) {
2472 for (Symbol s : t.tsym.members().getSymbols(s -> s.kind == VAR && (s.flags() & RECORD) != 0)) {
2473 vars = vars.prepend((VarSymbol)s);
2474 }
2475 }
2476 t = types.supertype(t);
2477 }
2478 return vars;
2479 }
2480
2481 /** Translate a record. */
2482 private void visitRecordDef(JCClassDecl tree) {
2483 make_at(tree.pos());
2484 List<VarSymbol> vars = recordVars(tree.type);
2485 MethodHandleSymbol[] getterMethHandles = new MethodHandleSymbol[vars.size()];
2486 int index = 0;
2487 for (VarSymbol var : vars) {
2488 if (var.owner != tree.sym) {
2489 var = new VarSymbol(var.flags_field, var.name, var.type, tree.sym);
2490 }
2491 getterMethHandles[index] = var.asMethodHandle(true);
2492 index++;
2493 }
2494
2495 tree.defs = tree.defs.appendList(generateMandatedAccessors(tree));
2496 tree.defs = tree.defs.appendList(List.of(
2497 generateRecordMethod(tree, names.toString, vars, getterMethHandles),
2498 generateRecordMethod(tree, names.hashCode, vars, getterMethHandles),
2499 generateRecordMethod(tree, names.equals, vars, getterMethHandles)
2500 ));
2501 }
2502
2503 JCTree generateRecordMethod(JCClassDecl tree, Name name, List<VarSymbol> vars, MethodHandleSymbol[] getterMethHandles) {
2504 make_at(tree.pos());
2505 boolean isEquals = name == names.equals;
2506 MethodSymbol msym = lookupMethod(tree.pos(),
2507 name,
2508 tree.sym.type,
2509 isEquals ? List.of(syms.objectType) : List.nil());
2510 // compiler generated methods have the record flag set, user defined ones dont
2511 if ((msym.flags() & RECORD) != 0) {
2512 /* class java.lang.runtime.ObjectMethods provides a common bootstrap that provides a customized implementation
2513 * for methods: toString, hashCode and equals. Here we just need to generate and indy call to:
2514 * java.lang.runtime.ObjectMethods::bootstrap and provide: the record class, the record component names and
2515 * the accessors.
2516 */
2517 Name bootstrapName = names.bootstrap;
2518 LoadableConstant[] staticArgsValues = new LoadableConstant[2 + getterMethHandles.length];
2519 staticArgsValues[0] = (ClassType)tree.sym.type;
2520 String concatNames = vars.stream()
2521 .map(v -> v.name)
2522 .collect(Collectors.joining(";", "", ""));
2523 staticArgsValues[1] = LoadableConstant.String(concatNames);
2524 int index = 2;
2525 for (MethodHandleSymbol mho : getterMethHandles) {
2526 staticArgsValues[index] = mho;
2527 index++;
2528 }
2529
2530 List<Type> staticArgTypes = List.of(syms.classType,
2531 syms.stringType,
2532 new ArrayType(syms.methodHandleType, syms.arrayClass));
2533
2534 JCFieldAccess qualifier = makeIndyQualifier(syms.objectMethodsType, tree, msym,
2535 List.of(syms.methodHandleLookupType,
2536 syms.stringType,
2537 syms.typeDescriptorType).appendList(staticArgTypes),
2538 staticArgsValues, bootstrapName, name, false);
2539
2540 VarSymbol _this = new VarSymbol(SYNTHETIC, names._this, tree.sym.type, tree.sym);
2541
2542 JCMethodInvocation proxyCall;
2543 if (!isEquals) {
2544 proxyCall = make.Apply(List.nil(), qualifier, List.of(make.Ident(_this)));
2545 } else {
2546 VarSymbol o = msym.params.head;
2547 o.adr = 0;
2548 proxyCall = make.Apply(List.nil(), qualifier, List.of(make.Ident(_this), make.Ident(o)));
2549 }
2550 proxyCall.type = qualifier.type;
2551 return make.MethodDef(msym, make.Block(0, List.of(make.Return(proxyCall))));
2552 } else {
2553 return make.Block(SYNTHETIC, List.nil());
2554 }
2555 }
2556
2557 private String argsTypeSig(List<Type> typeList) {
2558 LowerSignatureGenerator sg = new LowerSignatureGenerator();
2559 sg.assembleSig(typeList);
2560 return sg.toString();
2561 }
2562
2563 /**
2564 * Signature Generation
2565 */
2566 private class LowerSignatureGenerator extends Types.SignatureGenerator {
2567
2568 /**
2569 * An output buffer for type signatures.
2570 */
2571 StringBuilder sb = new StringBuilder();
2572
2573 LowerSignatureGenerator() {
2574 types.super();
2575 }
2576
2577 @Override
2578 protected void append(char ch) {
2579 sb.append(ch);
2580 }
2581
2582 @Override
2583 protected void append(byte[] ba) {
2584 sb.append(new String(ba));
2585 }
2586
2587 @Override
2588 protected void append(Name name) {
2589 sb.append(name.toString());
2590 }
2591
2592 @Override
2593 public String toString() {
2594 return sb.toString();
2595 }
2596 }
2597
2598 /**
2599 * Creates an indy qualifier, helpful to be part of an indy invocation
2600 * @param site the site
2601 * @param tree a class declaration tree
2602 * @param msym the method symbol
2603 * @param staticArgTypes the static argument types
2604 * @param staticArgValues the static argument values
2605 * @param bootstrapName the bootstrap name to look for
2606 * @param argName normally bootstraps receives a method name as second argument, if you want that name
2607 * to be different to that of the bootstrap name pass a different name here
2608 * @param isStatic is it static or not
2609 * @return a field access tree
2610 */
2611 JCFieldAccess makeIndyQualifier(
2612 Type site,
2613 JCClassDecl tree,
2614 MethodSymbol msym,
2615 List<Type> staticArgTypes,
2616 LoadableConstant[] staticArgValues,
2617 Name bootstrapName,
2618 Name argName,
2619 boolean isStatic) {
2620 MethodSymbol bsm = rs.resolveInternalMethod(tree.pos(), attrEnv, site,
2621 bootstrapName, staticArgTypes, List.nil());
2622
2623 MethodType indyType = msym.type.asMethodType();
2624 indyType = new MethodType(
2625 isStatic ? List.nil() : indyType.argtypes.prepend(tree.sym.type),
2626 indyType.restype,
2627 indyType.thrown,
2628 syms.methodClass
2629 );
2630 DynamicMethodSymbol dynSym = new DynamicMethodSymbol(argName,
2631 syms.noSymbol,
2632 bsm.asHandle(),
2633 indyType,
2634 staticArgValues);
2635 JCFieldAccess qualifier = make.Select(make.QualIdent(site.tsym), argName);
2636 qualifier.sym = dynSym;
2637 qualifier.type = msym.type.asMethodType().restype;
2638 return qualifier;
2639 }
2640
2641 public void visitMethodDef(JCMethodDecl tree) {
2642 if (tree.name == names.init && (currentClass.flags_field&ENUM) != 0) {
2643 // Add "String $enum$name, int $enum$ordinal" to the beginning of the
2644 // argument list for each constructor of an enum.
2645 JCVariableDecl nameParam = make_at(tree.pos()).
2646 Param(names.fromString(target.syntheticNameChar() +
2647 "enum" + target.syntheticNameChar() + "name"),
2648 syms.stringType, tree.sym);
2649 nameParam.mods.flags |= SYNTHETIC; nameParam.sym.flags_field |= SYNTHETIC;
2650 JCVariableDecl ordParam = make.
2651 Param(names.fromString(target.syntheticNameChar() +
2652 "enum" + target.syntheticNameChar() +
2653 "ordinal"),
2654 syms.intType, tree.sym);
2655 ordParam.mods.flags |= SYNTHETIC; ordParam.sym.flags_field |= SYNTHETIC;
2656
2657 MethodSymbol m = tree.sym;
2658 tree.params = tree.params.prepend(ordParam).prepend(nameParam);
2659
2660 m.extraParams = m.extraParams.prepend(ordParam.sym);
2661 m.extraParams = m.extraParams.prepend(nameParam.sym);
2662 Type olderasure = m.erasure(types);
2663 m.erasure_field = new MethodType(
2664 olderasure.getParameterTypes().prepend(syms.intType).prepend(syms.stringType),
2665 olderasure.getReturnType(),
2666 olderasure.getThrownTypes(),
2667 syms.methodClass);
2668 }
2669
2670 Type prevRestype = currentRestype;
2671 JCMethodDecl prevMethodDef = currentMethodDef;
2672 MethodSymbol prevMethodSym = currentMethodSym;
2673 int prevVariableIndex = variableIndex;
2674 try {
2675 currentRestype = types.erasure(tree.type.getReturnType());
2676 currentMethodDef = tree;
2677 currentMethodSym = tree.sym;
2678 variableIndex = 0;
2679 visitMethodDefInternal(tree);
2680 } finally {
2681 currentRestype = prevRestype;
2682 currentMethodDef = prevMethodDef;
2683 currentMethodSym = prevMethodSym;
2684 variableIndex = prevVariableIndex;
2685 }
2686 }
2687
2688 private void visitMethodDefInternal(JCMethodDecl tree) {
2689 if (tree.name == names.init &&
2690 !currentClass.isStatic() &&
2691 (currentClass.isInner() || currentClass.isDirectlyOrIndirectlyLocal())) {
2692 // We are seeing a constructor of an inner class.
2693 MethodSymbol m = tree.sym;
2694
2695 // Push a new proxy scope for constructor parameters.
2696 // and create definitions for any this$n and proxy parameters.
2697 Map<Symbol, Symbol> prevProxies = proxies;
2698 proxies = new HashMap<>(proxies);
2699 List<VarSymbol> prevOuterThisStack = outerThisStack;
2700 List<VarSymbol> fvs = freevars(currentClass);
2701 JCVariableDecl otdef = null;
2702 if (currentClass.hasOuterInstance())
2703 otdef = outerThisDef(tree.pos, m);
2704 List<JCVariableDecl> fvdefs = freevarDefs(tree.pos, fvs, m, PARAMETER);
2705
2706 // Recursively translate result type, parameters and thrown list.
2707 tree.restype = translate(tree.restype);
2708 tree.params = translateVarDefs(tree.params);
2709 tree.thrown = translate(tree.thrown);
2710
2711 // when compiling stubs, don't process body
2712 if (tree.body == null) {
2713 result = tree;
2714 return;
2715 }
2716
2717 // Add this$n (if needed) in front of and free variables behind
2718 // constructor parameter list.
2719 tree.params = tree.params.appendList(fvdefs);
2720 if (currentClass.hasOuterInstance()) {
2721 tree.params = tree.params.prepend(otdef);
2722 }
2723
2724 // Determine whether this constructor has a super() invocation
2725 boolean invokesSuper = TreeInfo.hasConstructorCall(tree, names._super);
2726
2727 // Create initializers for this$n and proxies
2728 ListBuffer<JCStatement> added = new ListBuffer<>();
2729 if (fvs.nonEmpty()) {
2730 List<Type> addedargtypes = List.nil();
2731 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) {
2732 m.capturedLocals =
2733 m.capturedLocals.prepend((VarSymbol)
2734 (proxies.get(l.head)));
2735 if (invokesSuper) {
2736 added = added.prepend(
2737 initField(tree.body.pos, proxies.get(l.head), prevProxies.get(l.head)));
2738 }
2739 addedargtypes = addedargtypes.prepend(l.head.erasure(types));
2740 }
2741 Type olderasure = m.erasure(types);
2742 m.erasure_field = new MethodType(
2743 olderasure.getParameterTypes().appendList(addedargtypes),
2744 olderasure.getReturnType(),
2745 olderasure.getThrownTypes(),
2746 syms.methodClass);
2747 }
2748
2749 // Recursively translate existing local statements
2750 tree.body.stats = translate(tree.body.stats);
2751
2752 // Prepend initializers in front of super() call
2753 if (added.nonEmpty()) {
2754 List<JCStatement> initializers = added.toList();
2755 TreeInfo.mapSuperCalls(tree.body, supercall -> make.Block(0, initializers.append(supercall)));
2756 }
2757
2758 // pop local variables from proxy stack
2759 proxies = prevProxies;
2760
2761 outerThisStack = prevOuterThisStack;
2762 } else {
2763 super.visitMethodDef(tree);
2764 }
2765 if (tree.name == names.init && ((tree.sym.flags_field & Flags.COMPACT_RECORD_CONSTRUCTOR) != 0 ||
2766 (tree.sym.flags_field & (GENERATEDCONSTR | RECORD)) == (GENERATEDCONSTR | RECORD))) {
2767 // lets find out if there is any field waiting to be initialized
2768 ListBuffer<VarSymbol> fields = new ListBuffer<>();
2769 for (Symbol sym : currentClass.getEnclosedElements()) {
2770 if (sym.kind == Kinds.Kind.VAR && ((sym.flags() & RECORD) != 0))
2771 fields.append((VarSymbol) sym);
2772 }
2773 ListBuffer<JCStatement> initializers = new ListBuffer<>();
2774 for (VarSymbol field: fields) {
2775 if ((field.flags_field & Flags.UNINITIALIZED_FIELD) != 0) {
2776 VarSymbol param = tree.params.stream().filter(p -> p.name == field.name).findFirst().get().sym;
2777 make.at(tree.pos);
2778 initializers.add(make.Exec(
2779 make.Assign(
2780 make.Select(make.This(field.owner.erasure(types)), field),
2781 make.Ident(param)).setType(field.erasure(types))));
2782 field.flags_field &= ~Flags.UNINITIALIZED_FIELD;
2783 }
2784 }
2785 if (initializers.nonEmpty()) {
2786 if (allowValueClasses && (tree.sym.owner.isValueClass() || tree.sym.owner.hasStrict() || ((ClassSymbol)tree.sym.owner).isRecord())) {
2787 TreeInfo.mapSuperCalls(tree.body, supercall -> make.Block(0, initializers.toList().append(supercall)));
2788 } else {
2789 tree.body.stats = tree.body.stats.appendList(initializers);
2790 }
2791 }
2792 }
2793 result = tree;
2794 }
2795
2796 public void visitTypeCast(JCTypeCast tree) {
2797 tree.clazz = translate(tree.clazz);
2798 if (tree.type.isPrimitive() != tree.expr.type.isPrimitive())
2799 tree.expr = translate(tree.expr, tree.type);
2800 else
2801 tree.expr = translate(tree.expr);
2802 result = tree;
2803 }
2804
2805 /**
2806 * All the exactness checks between primitive types that require a run-time
2807 * check are in {@code java.lang.runtime.ExactConversionsSupport}. Those methods
2808 * are in the form {@code ExactConversionsSupport.is<S>To<T>Exact} where both
2809 * {@code S} and {@code T} are primitive types and correspond to the runtime
2810 * action that will be executed to check whether a certain value (that is passed
2811 * as a parameter) can be converted to {@code T} without loss of information.
2812 *
2813 * Rewrite {@code instanceof if expr : Object} and Type is primitive type:
2814 *
2815 * {@snippet :
2816 * Object v = ...
2817 * if (v instanceof float)
2818 * =>
2819 * if (let tmp$123 = v; tmp$123 instanceof Float)
2820 * }
2821 *
2822 * Rewrite {@code instanceof if expr : wrapper reference type}
2823 *
2824 * {@snippet :
2825 * Integer v = ...
2826 * if (v instanceof float)
2827 * =>
2828 * if (let tmp$123 = v; tmp$123 != null && ExactConversionsSupport.intToFloatExact(tmp$123.intValue()))
2829 * }
2830 *
2831 * Rewrite {@code instanceof if expr : primitive}
2832 *
2833 * {@snippet :
2834 * int v = ...
2835 * if (v instanceof float)
2836 * =>
2837 * if (let tmp$123 = v; ExactConversionsSupport.intToFloatExact(tmp$123))
2838 * }
2839 *
2840 * More rewritings:
2841 * <ul>
2842 * <li>If the {@code instanceof} check is unconditionally exact rewrite to true.</li>
2843 * <li>If expression type is {@code Byte}, {@code Short}, {@code Integer}, ..., an
2844 * unboxing conversion followed by a widening primitive conversion.</li>
2845 * <li>If expression type is a supertype: {@code Number}, a narrowing reference
2846 * conversion followed by an unboxing conversion.</li>
2847 * </ul>
2848 */
2849 public void visitTypeTest(JCInstanceOf tree) {
2850 if (tree.expr.type.isPrimitive() || tree.pattern.type.isPrimitive()) {
2851 JCStatement prefixStatement;
2852 JCExpression exactnessCheck;
2853 JCExpression instanceOfExpr = translate(tree.expr);
2854
2855 if (types.isUnconditionallyExactTypeBased(tree.expr.type, tree.pattern.type)) {
2856 // instanceOfExpr; true
2857 prefixStatement = make.Exec(instanceOfExpr);
2858 exactnessCheck = make.Literal(BOOLEAN, 1).setType(syms.booleanType.constType(1));
2859 } else if (tree.expr.type.isPrimitive()) {
2860 // ExactConversionSupport.isXxxExact(instanceOfExpr)
2861 prefixStatement = null;
2862 exactnessCheck = getExactnessCheck(tree, instanceOfExpr);
2863 } else if (tree.expr.type.isReference()) {
2864 if (types.isUnconditionallyExactTypeBased(types.unboxedType(tree.expr.type), tree.pattern.type)) {
2865 // instanceOfExpr != null
2866 prefixStatement = null;
2867 exactnessCheck = makeBinary(NE, instanceOfExpr, makeNull());
2868 } else {
2869 // We read the result of instanceOfExpr, so create variable
2870 VarSymbol dollar_s = new VarSymbol(FINAL | SYNTHETIC,
2871 names.fromString("tmp" + variableIndex++ + this.target.syntheticNameChar()),
2872 types.erasure(tree.expr.type),
2873 currentMethodSym);
2874 prefixStatement = make.at(tree.pos())
2875 .VarDef(dollar_s, instanceOfExpr);
2876
2877 JCExpression nullCheck =
2878 makeBinary(NE,
2879 make.Ident(dollar_s),
2880 makeNull());
2881
2882 if (types.unboxedType(tree.expr.type).isPrimitive()) {
2883 exactnessCheck =
2884 makeBinary(AND,
2885 nullCheck,
2886 getExactnessCheck(tree, boxIfNeeded(make.Ident(dollar_s), types.unboxedType(tree.expr.type))));
2887 } else {
2888 exactnessCheck =
2889 makeBinary(AND,
2890 nullCheck,
2891 make.at(tree.pos())
2892 .TypeTest(make.Ident(dollar_s), make.Type(types.boxedClass(tree.pattern.type).type))
2893 .setType(syms.booleanType));
2894 }
2895 }
2896 } else {
2897 throw Assert.error("Non primitive or reference type: " + tree.expr.type);
2898 }
2899 result = (prefixStatement == null ? exactnessCheck : make.LetExpr(List.of(prefixStatement), exactnessCheck))
2900 .setType(syms.booleanType);
2901 } else {
2902 tree.expr = translate(tree.expr);
2903 tree.pattern = translate(tree.pattern);
2904 result = tree;
2905 }
2906 }
2907
2908 // TypePairs should be in sync with the corresponding record in SwitchBootstraps
2909 record TypePairs(TypeSymbol from, TypeSymbol to) {
2910 public static TypePairs of(Symtab syms, Type from, Type to) {
2911 if (from == syms.byteType || from == syms.shortType || from == syms.charType) {
2912 from = syms.intType;
2913 }
2914 return new TypePairs(from, to);
2915 }
2916
2917 public TypePairs(Type from, Type to) {
2918 this(from.tsym, to.tsym);
2919 }
2920
2921 public static HashMap<TypePairs, String> initialize(Symtab syms) {
2922 HashMap<TypePairs, String> typePairToName = new HashMap<>();
2923 typePairToName.put(new TypePairs(syms.byteType, syms.charType), "isIntToCharExact"); // redirected
2924 typePairToName.put(new TypePairs(syms.shortType, syms.byteType), "isIntToByteExact"); // redirected
2925 typePairToName.put(new TypePairs(syms.shortType, syms.charType), "isIntToCharExact"); // redirected
2926 typePairToName.put(new TypePairs(syms.charType, syms.byteType), "isIntToByteExact"); // redirected
2927 typePairToName.put(new TypePairs(syms.charType, syms.shortType), "isIntToShortExact"); // redirected
2928 typePairToName.put(new TypePairs(syms.intType, syms.byteType), "isIntToByteExact");
2929 typePairToName.put(new TypePairs(syms.intType, syms.shortType), "isIntToShortExact");
2930 typePairToName.put(new TypePairs(syms.intType, syms.charType), "isIntToCharExact");
2931 typePairToName.put(new TypePairs(syms.intType, syms.floatType), "isIntToFloatExact");
2932 typePairToName.put(new TypePairs(syms.longType, syms.byteType), "isLongToByteExact");
2933 typePairToName.put(new TypePairs(syms.longType, syms.shortType), "isLongToShortExact");
2934 typePairToName.put(new TypePairs(syms.longType, syms.charType), "isLongToCharExact");
2935 typePairToName.put(new TypePairs(syms.longType, syms.intType), "isLongToIntExact");
2936 typePairToName.put(new TypePairs(syms.longType, syms.floatType), "isLongToFloatExact");
2937 typePairToName.put(new TypePairs(syms.longType, syms.doubleType), "isLongToDoubleExact");
2938 typePairToName.put(new TypePairs(syms.floatType, syms.byteType), "isFloatToByteExact");
2939 typePairToName.put(new TypePairs(syms.floatType, syms.shortType), "isFloatToShortExact");
2940 typePairToName.put(new TypePairs(syms.floatType, syms.charType), "isFloatToCharExact");
2941 typePairToName.put(new TypePairs(syms.floatType, syms.intType), "isFloatToIntExact");
2942 typePairToName.put(new TypePairs(syms.floatType, syms.longType), "isFloatToLongExact");
2943 typePairToName.put(new TypePairs(syms.doubleType, syms.byteType), "isDoubleToByteExact");
2944 typePairToName.put(new TypePairs(syms.doubleType, syms.shortType), "isDoubleToShortExact");
2945 typePairToName.put(new TypePairs(syms.doubleType, syms.charType), "isDoubleToCharExact");
2946 typePairToName.put(new TypePairs(syms.doubleType, syms.intType), "isDoubleToIntExact");
2947 typePairToName.put(new TypePairs(syms.doubleType, syms.longType), "isDoubleToLongExact");
2948 typePairToName.put(new TypePairs(syms.doubleType, syms.floatType), "isDoubleToFloatExact");
2949 return typePairToName;
2950 }
2951 }
2952
2953 private JCExpression getExactnessCheck(JCInstanceOf tree, JCExpression argument) {
2954 TypePairs pair = TypePairs.of(syms, types.unboxedTypeOrType(tree.expr.type), tree.pattern.type);
2955
2956 Name exactnessFunction = names.fromString(typePairToName.get(pair));
2957
2958 // Resolve the exactness method
2959 Symbol ecsym = lookupMethod(tree.pos(),
2960 exactnessFunction,
2961 syms.exactConversionsSupportType,
2962 List.of(pair.from.type));
2963
2964 // Generate the method call ExactnessChecks.<exactness method>(<argument>);
2965 JCFieldAccess select = make.Select(
2966 make.QualIdent(syms.exactConversionsSupportType.tsym),
2967 exactnessFunction);
2968 select.sym = ecsym;
2969 select.setType(syms.booleanType);
2970
2971 JCExpression exactnessCheck = make.Apply(List.nil(),
2972 select,
2973 List.of(argument));
2974 exactnessCheck.setType(syms.booleanType);
2975 return exactnessCheck;
2976 }
2977
2978 public void visitNewClass(JCNewClass tree) {
2979 ClassSymbol c = (ClassSymbol)tree.constructor.owner;
2980
2981 // Box arguments, if necessary
2982 boolean isEnum = (tree.constructor.owner.flags() & ENUM) != 0;
2983 List<Type> argTypes = tree.constructor.type.getParameterTypes();
2984 if (isEnum) argTypes = argTypes.prepend(syms.intType).prepend(syms.stringType);
2985 tree.args = boxArgs(argTypes, tree.args, tree.varargsElement);
2986 tree.varargsElement = null;
2987
2988 // If created class is local, add free variables after
2989 // explicit constructor arguments.
2990 if (c.isDirectlyOrIndirectlyLocal() && !c.isStatic()) {
2991 tree.args = tree.args.appendList(loadFreevars(tree.pos(), freevars(c)));
2992 }
2993
2994 // If an access constructor is used, append null as a last argument.
2995 Symbol constructor = accessConstructor(tree.pos(), tree.constructor);
2996 if (constructor != tree.constructor) {
2997 tree.args = tree.args.append(makeNull());
2998 tree.constructor = constructor;
2999 }
3000
3001 // If created class has an outer instance, and new is qualified, pass
3002 // qualifier as first argument. If new is not qualified, pass the
3003 // correct outer instance as first argument.
3004 if (c.hasOuterInstance()) {
3005 JCExpression thisArg;
3006 if (tree.encl != null) {
3007 thisArg = attr.makeNullCheck(translate(tree.encl));
3008 thisArg.type = tree.encl.type;
3009 } else if (c.isDirectlyOrIndirectlyLocal()) {
3010 // local class
3011 thisArg = makeThis(tree.pos(), c.innermostAccessibleEnclosingClass());
3012 } else {
3013 // nested class
3014 thisArg = makeOwnerThis(tree.pos(), c, false);
3015 if (currentMethodSym != null &&
3016 ((currentMethodSym.flags_field & (STATIC | BLOCK)) == BLOCK) &&
3017 currentMethodSym.owner.isValueClass()) {
3018 // instance initializer in a value class
3019 Set<JCExpression> outerThisSet = initializerOuterThis.get(currentClass);
3020 if (outerThisSet == null) {
3021 outerThisSet = new HashSet<>();
3022 }
3023 outerThisSet.add(thisArg);
3024 initializerOuterThis.put(currentClass, outerThisSet);
3025 }
3026 }
3027 tree.args = tree.args.prepend(thisArg);
3028 }
3029 tree.encl = null;
3030
3031 // If we have an anonymous class, create its flat version, rather
3032 // than the class or interface following new.
3033 if (tree.def != null) {
3034 translate(tree.def);
3035
3036 tree.clazz = access(make_at(tree.clazz.pos()).Ident(tree.def.sym));
3037 tree.def = null;
3038 } else {
3039 tree.clazz = access(c, tree.clazz, enclOp, false);
3040 }
3041 result = tree;
3042 }
3043
3044 // Simplify conditionals with known constant controlling expressions.
3045 // This allows us to avoid generating supporting declarations for
3046 // the dead code, which will not be eliminated during code generation.
3047 // Note that Flow.isFalse and Flow.isTrue only return true
3048 // for constant expressions in the sense of JLS 15.27, which
3049 // are guaranteed to have no side-effects. More aggressive
3050 // constant propagation would require that we take care to
3051 // preserve possible side-effects in the condition expression.
3052
3053 // One common case is equality expressions involving a constant and null.
3054 // Since null is not a constant expression (because null cannot be
3055 // represented in the constant pool), equality checks involving null are
3056 // not captured by Flow.isTrue/isFalse.
3057 // Equality checks involving a constant and null, e.g.
3058 // "" == null
3059 // are safe to simplify as no side-effects can occur.
3060
3061 private boolean isTrue(JCTree exp) {
3062 if (exp.type.isTrue())
3063 return true;
3064 Boolean b = expValue(exp);
3065 return b == null ? false : b;
3066 }
3067 private boolean isFalse(JCTree exp) {
3068 if (exp.type.isFalse())
3069 return true;
3070 Boolean b = expValue(exp);
3071 return b == null ? false : !b;
3072 }
3073 /* look for (in)equality relations involving null.
3074 * return true - if expression is always true
3075 * false - if expression is always false
3076 * null - if expression cannot be eliminated
3077 */
3078 private Boolean expValue(JCTree exp) {
3079 while (exp.hasTag(PARENS))
3080 exp = ((JCParens)exp).expr;
3081
3082 boolean eq;
3083 switch (exp.getTag()) {
3084 case EQ: eq = true; break;
3085 case NE: eq = false; break;
3086 default:
3087 return null;
3088 }
3089
3090 // we have a JCBinary(EQ|NE)
3091 // check if we have two literals (constants or null)
3092 JCBinary b = (JCBinary)exp;
3093 if (b.lhs.type.hasTag(BOT)) return expValueIsNull(eq, b.rhs);
3094 if (b.rhs.type.hasTag(BOT)) return expValueIsNull(eq, b.lhs);
3095 return null;
3096 }
3097 private Boolean expValueIsNull(boolean eq, JCTree t) {
3098 if (t.type.hasTag(BOT)) return Boolean.valueOf(eq);
3099 if (t.hasTag(LITERAL)) return Boolean.valueOf(!eq);
3100 return null;
3101 }
3102
3103 /** Visitor method for conditional expressions.
3104 */
3105 @Override
3106 public void visitConditional(JCConditional tree) {
3107 JCTree cond = tree.cond = translate(tree.cond, syms.booleanType);
3108 if (isTrue(cond) && noClassDefIn(tree.falsepart)) {
3109 result = convert(translate(tree.truepart, tree.type), tree.type);
3110 addPrunedInfo(cond);
3111 } else if (isFalse(cond) && noClassDefIn(tree.truepart)) {
3112 result = convert(translate(tree.falsepart, tree.type), tree.type);
3113 addPrunedInfo(cond);
3114 } else {
3115 // Condition is not a compile-time constant.
3116 tree.truepart = translate(tree.truepart, tree.type);
3117 tree.falsepart = translate(tree.falsepart, tree.type);
3118 result = tree;
3119 }
3120 }
3121 //where
3122 private JCExpression convert(JCExpression tree, Type pt) {
3123 if (tree.type == pt || tree.type.hasTag(BOT))
3124 return tree;
3125 JCExpression result = make_at(tree.pos()).TypeCast(make.Type(pt), tree);
3126 result.type = (tree.type.constValue() != null) ? cfolder.coerce(tree.type, pt)
3127 : pt;
3128 return result;
3129 }
3130
3131 /** Visitor method for if statements.
3132 */
3133 public void visitIf(JCIf tree) {
3134 JCTree cond = tree.cond = translate(tree.cond, syms.booleanType);
3135 if (isTrue(cond) && noClassDefIn(tree.elsepart)) {
3136 result = translate(tree.thenpart);
3137 addPrunedInfo(cond);
3138 } else if (isFalse(cond) && noClassDefIn(tree.thenpart)) {
3139 if (tree.elsepart != null) {
3140 result = translate(tree.elsepart);
3141 } else {
3142 result = make.Skip();
3143 }
3144 addPrunedInfo(cond);
3145 } else {
3146 // Condition is not a compile-time constant.
3147 tree.thenpart = translate(tree.thenpart);
3148 tree.elsepart = translate(tree.elsepart);
3149 result = tree;
3150 }
3151 }
3152
3153 /** Visitor method for assert statements. Translate them away.
3154 */
3155 public void visitAssert(JCAssert tree) {
3156 tree.cond = translate(tree.cond, syms.booleanType);
3157 if (!tree.cond.type.isTrue()) {
3158 JCExpression cond = assertFlagTest(tree.pos());
3159 List<JCExpression> exnArgs = (tree.detail == null) ?
3160 List.nil() : List.of(translate(tree.detail));
3161 if (!tree.cond.type.isFalse()) {
3162 cond = makeBinary
3163 (AND,
3164 cond,
3165 makeUnary(NOT, tree.cond));
3166 }
3167 result =
3168 make.If(cond,
3169 make_at(tree).
3170 Throw(makeNewClass(syms.assertionErrorType, exnArgs)),
3171 null);
3172 } else {
3173 result = make.Skip();
3174 }
3175 }
3176
3177 public void visitApply(JCMethodInvocation tree) {
3178 Symbol meth = TreeInfo.symbol(tree.meth);
3179 List<Type> argtypes = meth.type.getParameterTypes();
3180 if (meth.name == names.init && meth.owner == syms.enumSym)
3181 argtypes = argtypes.tail.tail;
3182 tree.args = boxArgs(argtypes, tree.args, tree.varargsElement);
3183 tree.varargsElement = null;
3184 Name methName = TreeInfo.name(tree.meth);
3185 if (meth.name==names.init) {
3186 // We are seeing a this(...) or super(...) constructor call.
3187 // If an access constructor is used, append null as a last argument.
3188 Symbol constructor = accessConstructor(tree.pos(), meth);
3189 if (constructor != meth) {
3190 tree.args = tree.args.append(makeNull());
3191 TreeInfo.setSymbol(tree.meth, constructor);
3192 }
3193
3194 // If we are calling a constructor of a local class, add
3195 // free variables after explicit constructor arguments.
3196 ClassSymbol c = (ClassSymbol)constructor.owner;
3197 if (c.isDirectlyOrIndirectlyLocal() && !c.isStatic()) {
3198 tree.args = tree.args.appendList(loadFreevars(tree.pos(), freevars(c)));
3199 }
3200
3201 // If we are calling a constructor of an enum class, pass
3202 // along the name and ordinal arguments
3203 if ((c.flags_field&ENUM) != 0 || c.getQualifiedName() == names.java_lang_Enum) {
3204 List<JCVariableDecl> params = currentMethodDef.params;
3205 if (currentMethodSym.owner.hasOuterInstance())
3206 params = params.tail; // drop this$n
3207 tree.args = tree.args
3208 .prepend(make_at(tree.pos()).Ident(params.tail.head.sym)) // ordinal
3209 .prepend(make.Ident(params.head.sym)); // name
3210 }
3211
3212 // If we are calling a constructor of a class with an outer
3213 // instance, and the call
3214 // is qualified, pass qualifier as first argument in front of
3215 // the explicit constructor arguments. If the call
3216 // is not qualified, pass the correct outer instance as
3217 // first argument. If we are a static class, there is no
3218 // such outer instance, so generate an error.
3219 if (c.hasOuterInstance()) {
3220 JCExpression thisArg;
3221 if (tree.meth.hasTag(SELECT)) {
3222 thisArg = attr.
3223 makeNullCheck(translate(((JCFieldAccess) tree.meth).selected));
3224 tree.meth = make.Ident(constructor);
3225 ((JCIdent) tree.meth).name = methName;
3226 } else if (c.isDirectlyOrIndirectlyLocal() || methName == names._this){
3227 // local class or this() call
3228 thisArg = makeThis(tree.meth.pos(), c.innermostAccessibleEnclosingClass());
3229 } else if (currentClass.isStatic()) {
3230 // super() call from static nested class - invalid
3231 log.error(tree.pos(),
3232 Errors.NoEnclInstanceOfTypeInScope(c.type.getEnclosingType().tsym));
3233 thisArg = make.Literal(BOT, null).setType(syms.botType);
3234 } else {
3235 // super() call of nested class - never pick 'this'
3236 thisArg = makeOwnerThisN(tree.meth.pos(), c, false);
3237 }
3238 tree.args = tree.args.prepend(thisArg);
3239 }
3240 } else {
3241 // We are seeing a normal method invocation; translate this as usual.
3242 tree.meth = translate(tree.meth);
3243
3244 // If the translated method itself is an Apply tree, we are
3245 // seeing an access method invocation. In this case, append
3246 // the method arguments to the arguments of the access method.
3247 if (tree.meth.hasTag(APPLY)) {
3248 JCMethodInvocation app = (JCMethodInvocation)tree.meth;
3249 app.args = tree.args.prependList(app.args);
3250 result = app;
3251 return;
3252 }
3253 }
3254 if (tree.args.stream().anyMatch(c -> c == null)) {
3255 throw new AssertionError("Whooops before: " + tree);
3256 }
3257 result = tree;
3258 }
3259
3260 List<JCExpression> boxArgs(List<Type> parameters, List<JCExpression> _args, Type varargsElement) {
3261 List<JCExpression> args = _args;
3262 if (parameters.isEmpty()) return args;
3263 boolean anyChanges = false;
3264 ListBuffer<JCExpression> result = new ListBuffer<>();
3265 while (parameters.tail.nonEmpty()) {
3266 JCExpression arg = translate(args.head, parameters.head);
3267 anyChanges |= (arg != args.head);
3268 result.append(arg);
3269 args = args.tail;
3270 parameters = parameters.tail;
3271 }
3272 Type parameter = parameters.head;
3273 if (varargsElement != null) {
3274 anyChanges = true;
3275 ListBuffer<JCExpression> elems = new ListBuffer<>();
3276 while (args.nonEmpty()) {
3277 JCExpression arg = translate(args.head, varargsElement);
3278 elems.append(arg);
3279 args = args.tail;
3280 }
3281 JCNewArray boxedArgs = make.NewArray(make.Type(varargsElement),
3282 List.nil(),
3283 elems.toList());
3284 boxedArgs.type = new ArrayType(varargsElement, syms.arrayClass);
3285 result.append(boxedArgs);
3286 } else {
3287 if (args.length() != 1) throw new AssertionError(args);
3288 JCExpression arg = translate(args.head, parameter);
3289 anyChanges |= (arg != args.head);
3290 result.append(arg);
3291 if (!anyChanges) return _args;
3292 }
3293 return result.toList();
3294 }
3295
3296 /** Expand a boxing or unboxing conversion if needed. */
3297 @SuppressWarnings("unchecked") // XXX unchecked
3298 <T extends JCExpression> T boxIfNeeded(T tree, Type type) {
3299 Assert.check(!type.hasTag(VOID));
3300 if (type.hasTag(NONE))
3301 return tree;
3302 boolean havePrimitive = tree.type.isPrimitive();
3303 if (havePrimitive == type.isPrimitive())
3304 return tree;
3305 if (havePrimitive) {
3306 Type unboxedTarget = types.unboxedType(type);
3307 if (!unboxedTarget.hasTag(NONE)) {
3308 if (!types.isSubtype(tree.type, unboxedTarget)) //e.g. Character c = 89;
3309 tree.type = unboxedTarget.constType(tree.type.constValue());
3310 return (T)boxPrimitive(tree, types.erasure(type));
3311 } else {
3312 tree = (T)boxPrimitive(tree);
3313 }
3314 } else {
3315 tree = (T)unbox(tree, type);
3316 }
3317 return tree;
3318 }
3319
3320 /** Box up a single primitive expression. */
3321 JCExpression boxPrimitive(JCExpression tree) {
3322 return boxPrimitive(tree, types.boxedClass(tree.type).type);
3323 }
3324
3325 /** Box up a single primitive expression. */
3326 JCExpression boxPrimitive(JCExpression tree, Type box) {
3327 make_at(tree.pos());
3328 Symbol valueOfSym = lookupMethod(tree.pos(),
3329 names.valueOf,
3330 box,
3331 List.<Type>nil()
3332 .prepend(tree.type));
3333 return make.App(make.QualIdent(valueOfSym), List.of(tree));
3334 }
3335
3336 /** Unbox an object to a primitive value. */
3337 JCExpression unbox(JCExpression tree, Type primitive) {
3338 Type unboxedType = types.unboxedType(tree.type);
3339 if (unboxedType.hasTag(NONE)) {
3340 unboxedType = primitive;
3341 if (!unboxedType.isPrimitive())
3342 throw new AssertionError(unboxedType);
3343 make_at(tree.pos());
3344 tree = make.TypeCast(types.boxedClass(unboxedType).type, tree);
3345 } else {
3346 // There must be a conversion from unboxedType to primitive.
3347 if (!types.isSubtype(unboxedType, primitive))
3348 throw new AssertionError(tree);
3349 }
3350 make_at(tree.pos());
3351 Symbol valueSym = lookupMethod(tree.pos(),
3352 unboxedType.tsym.name.append(names.Value), // x.intValue()
3353 tree.type,
3354 List.nil());
3355 return make.App(make.Select(tree, valueSym));
3356 }
3357
3358 /** Visitor method for parenthesized expressions.
3359 * If the subexpression has changed, omit the parens.
3360 */
3361 public void visitParens(JCParens tree) {
3362 JCTree expr = translate(tree.expr);
3363 result = ((expr == tree.expr) ? tree : expr);
3364 }
3365
3366 public void visitIndexed(JCArrayAccess tree) {
3367 tree.indexed = translate(tree.indexed);
3368 tree.index = translate(tree.index, syms.intType);
3369 result = tree;
3370 }
3371
3372 public void visitAssign(JCAssign tree) {
3373 tree.lhs = translate(tree.lhs, tree);
3374 tree.rhs = translate(tree.rhs, tree.lhs.type);
3375
3376 // If translated left hand side is an Apply, we are
3377 // seeing an access method invocation. In this case, append
3378 // right hand side as last argument of the access method.
3379 if (tree.lhs.hasTag(APPLY)) {
3380 JCMethodInvocation app = (JCMethodInvocation)tree.lhs;
3381 app.args = List.of(tree.rhs).prependList(app.args);
3382 result = app;
3383 } else {
3384 result = tree;
3385 }
3386 }
3387
3388 public void visitAssignop(final JCAssignOp tree) {
3389 final boolean boxingReq = !tree.lhs.type.isPrimitive() &&
3390 tree.operator.type.getReturnType().isPrimitive();
3391
3392 AssignopDependencyScanner depScanner = new AssignopDependencyScanner(tree);
3393 depScanner.scan(tree.rhs);
3394
3395 if (boxingReq || depScanner.dependencyFound) {
3396 // boxing required; need to rewrite as x = (unbox typeof x)(x op y);
3397 // or if x == (typeof x)z then z = (unbox typeof x)((typeof x)z op y)
3398 // (but without recomputing x)
3399 JCTree newTree = abstractLval(tree.lhs, lhs -> {
3400 Tag newTag = tree.getTag().noAssignOp();
3401 // Erasure (TransTypes) can change the type of
3402 // tree.lhs. However, we can still get the
3403 // unerased type of tree.lhs as it is stored
3404 // in tree.type in Attr.
3405 OperatorSymbol newOperator = operators.resolveBinary(tree,
3406 newTag,
3407 tree.type,
3408 tree.rhs.type);
3409 //Need to use the "lhs" at two places, once on the future left hand side
3410 //and once in the future binary operator. But further processing may change
3411 //the components of the tree in place (see visitSelect for e.g. <Class>.super.<ident>),
3412 //so cloning the tree to avoid interference between the uses:
3413 JCExpression expr = (JCExpression) lhs.clone();
3414 if (expr.type != tree.type)
3415 expr = make.TypeCast(tree.type, expr);
3416 JCBinary opResult = make.Binary(newTag, expr, tree.rhs);
3417 opResult.operator = newOperator;
3418 opResult.type = newOperator.type.getReturnType();
3419 JCExpression newRhs = boxingReq ?
3420 make.TypeCast(types.unboxedType(tree.type), opResult) :
3421 opResult;
3422 return make.Assign(lhs, newRhs).setType(tree.type);
3423 });
3424 result = translate(newTree);
3425 return;
3426 }
3427 tree.lhs = translate(tree.lhs, tree);
3428 tree.rhs = translate(tree.rhs, tree.operator.type.getParameterTypes().tail.head);
3429
3430 // If translated left hand side is an Apply, we are
3431 // seeing an access method invocation. In this case, append
3432 // right hand side as last argument of the access method.
3433 if (tree.lhs.hasTag(APPLY)) {
3434 JCMethodInvocation app = (JCMethodInvocation)tree.lhs;
3435 // if operation is a += on strings,
3436 // make sure to convert argument to string
3437 JCExpression rhs = tree.operator.opcode == string_add
3438 ? makeString(tree.rhs)
3439 : tree.rhs;
3440 app.args = List.of(rhs).prependList(app.args);
3441 result = app;
3442 } else {
3443 result = tree;
3444 }
3445 }
3446
3447 class AssignopDependencyScanner extends TreeScanner {
3448
3449 Symbol sym;
3450 boolean dependencyFound = false;
3451
3452 AssignopDependencyScanner(JCAssignOp tree) {
3453 this.sym = TreeInfo.symbol(tree.lhs);
3454 }
3455
3456 @Override
3457 public void scan(JCTree tree) {
3458 if (tree != null && sym != null) {
3459 tree.accept(this);
3460 }
3461 }
3462
3463 @Override
3464 public void visitAssignop(JCAssignOp tree) {
3465 if (TreeInfo.symbol(tree.lhs) == sym) {
3466 dependencyFound = true;
3467 return;
3468 }
3469 super.visitAssignop(tree);
3470 }
3471
3472 @Override
3473 public void visitUnary(JCUnary tree) {
3474 if (TreeInfo.symbol(tree.arg) == sym) {
3475 dependencyFound = true;
3476 return;
3477 }
3478 super.visitUnary(tree);
3479 }
3480 }
3481
3482 /** Lower a tree of the form e++ or e-- where e is an object type */
3483 JCExpression lowerBoxedPostop(final JCUnary tree) {
3484 // translate to tmp1=lval(e); tmp2=tmp1; tmp1 OP 1; tmp2
3485 // or
3486 // translate to tmp1=lval(e); tmp2=tmp1; (typeof tree)tmp1 OP 1; tmp2
3487 // where OP is += or -=
3488 final boolean cast = TreeInfo.skipParens(tree.arg).hasTag(TYPECAST);
3489 return abstractLval(tree.arg, tmp1 -> abstractRval(tmp1, tree.arg.type, tmp2 -> {
3490 Tag opcode = (tree.hasTag(POSTINC))
3491 ? PLUS_ASG : MINUS_ASG;
3492 //"tmp1" and "tmp2" may refer to the same instance
3493 //(for e.g. <Class>.super.<ident>). But further processing may
3494 //change the components of the tree in place (see visitSelect),
3495 //so cloning the tree to avoid interference between the two uses:
3496 JCExpression lhs = (JCExpression)tmp1.clone();
3497 lhs = cast
3498 ? make.TypeCast(tree.arg.type, lhs)
3499 : lhs;
3500 JCExpression update = makeAssignop(opcode,
3501 lhs,
3502 make.Literal(1));
3503 return makeComma(update, tmp2);
3504 }));
3505 }
3506
3507 public void visitUnary(JCUnary tree) {
3508 boolean isUpdateOperator = tree.getTag().isIncOrDecUnaryOp();
3509 if (isUpdateOperator && !tree.arg.type.isPrimitive()) {
3510 switch(tree.getTag()) {
3511 case PREINC: // ++ e
3512 // translate to e += 1
3513 case PREDEC: // -- e
3514 // translate to e -= 1
3515 {
3516 JCTree.Tag opcode = (tree.hasTag(PREINC))
3517 ? PLUS_ASG : MINUS_ASG;
3518 JCAssignOp newTree = makeAssignop(opcode,
3519 tree.arg,
3520 make.Literal(1));
3521 result = translate(newTree, tree.type);
3522 return;
3523 }
3524 case POSTINC: // e ++
3525 case POSTDEC: // e --
3526 {
3527 result = translate(lowerBoxedPostop(tree), tree.type);
3528 return;
3529 }
3530 }
3531 throw new AssertionError(tree);
3532 }
3533
3534 tree.arg = boxIfNeeded(translate(tree.arg, tree), tree.type);
3535
3536 if (tree.hasTag(NOT) && tree.arg.type.constValue() != null) {
3537 tree.type = cfolder.fold1(bool_not, tree.arg.type);
3538 }
3539
3540 // If translated left hand side is an Apply, we are
3541 // seeing an access method invocation. In this case, return
3542 // that access method invocation as result.
3543 if (isUpdateOperator && tree.arg.hasTag(APPLY)) {
3544 result = tree.arg;
3545 } else {
3546 result = tree;
3547 }
3548 }
3549
3550 public void visitBinary(JCBinary tree) {
3551 List<Type> formals = tree.operator.type.getParameterTypes();
3552 JCTree lhs = tree.lhs = translate(tree.lhs, formals.head);
3553 switch (tree.getTag()) {
3554 case OR:
3555 if (isTrue(lhs)) {
3556 result = lhs;
3557 return;
3558 }
3559 if (isFalse(lhs)) {
3560 result = translate(tree.rhs, formals.tail.head);
3561 return;
3562 }
3563 break;
3564 case AND:
3565 if (isFalse(lhs)) {
3566 result = lhs;
3567 return;
3568 }
3569 if (isTrue(lhs)) {
3570 result = translate(tree.rhs, formals.tail.head);
3571 return;
3572 }
3573 break;
3574 }
3575 tree.rhs = translate(tree.rhs, formals.tail.head);
3576 result = tree;
3577 }
3578
3579 public void visitIdent(JCIdent tree) {
3580 result = access(tree.sym, tree, enclOp, false);
3581 }
3582
3583 /** Translate away the foreach loop. */
3584 public void visitForeachLoop(JCEnhancedForLoop tree) {
3585 if (types.elemtype(tree.expr.type) == null)
3586 visitIterableForeachLoop(tree);
3587 else
3588 visitArrayForeachLoop(tree);
3589 }
3590 // where
3591 /**
3592 * A statement of the form
3593 *
3594 * <pre>
3595 * for ( T v : arrayexpr ) stmt;
3596 * </pre>
3597 *
3598 * (where arrayexpr is of an array type) gets translated to
3599 *
3600 * <pre>{@code
3601 * for ( { arraytype #arr = arrayexpr;
3602 * int #len = array.length;
3603 * int #i = 0; };
3604 * #i < #len; i$++ ) {
3605 * T v = arr$[#i];
3606 * stmt;
3607 * }
3608 * }</pre>
3609 *
3610 * where #arr, #len, and #i are freshly named synthetic local variables.
3611 */
3612 private void visitArrayForeachLoop(JCEnhancedForLoop tree) {
3613 make_at(tree.expr.pos());
3614 VarSymbol arraycache = new VarSymbol(SYNTHETIC,
3615 names.fromString("arr" + target.syntheticNameChar()),
3616 tree.expr.type,
3617 currentMethodSym);
3618 JCStatement arraycachedef = make.VarDef(arraycache, tree.expr);
3619 VarSymbol lencache = new VarSymbol(SYNTHETIC,
3620 names.fromString("len" + target.syntheticNameChar()),
3621 syms.intType,
3622 currentMethodSym);
3623 JCStatement lencachedef = make.
3624 VarDef(lencache, make.Select(make.Ident(arraycache), syms.lengthVar));
3625 VarSymbol index = new VarSymbol(SYNTHETIC,
3626 names.fromString("i" + target.syntheticNameChar()),
3627 syms.intType,
3628 currentMethodSym);
3629
3630 JCVariableDecl indexdef = make.VarDef(index, make.Literal(INT, 0));
3631 indexdef.init.type = indexdef.type = syms.intType.constType(0);
3632
3633 List<JCStatement> loopinit = List.of(arraycachedef, lencachedef, indexdef);
3634 JCBinary cond = makeBinary(LT, make.Ident(index), make.Ident(lencache));
3635
3636 JCExpressionStatement step = make.Exec(makeUnary(PREINC, make.Ident(index)));
3637
3638 Type elemtype = types.elemtype(tree.expr.type);
3639 JCExpression loopvarinit = make.Indexed(make.Ident(arraycache),
3640 make.Ident(index)).setType(elemtype);
3641 JCVariableDecl loopvardef = (JCVariableDecl)make.VarDef(tree.var.mods,
3642 tree.var.name,
3643 tree.var.vartype,
3644 loopvarinit).setType(tree.var.type);
3645 loopvardef.sym = tree.var.sym;
3646 JCBlock body = make.
3647 Block(0, List.of(loopvardef, tree.body));
3648
3649 result = translate(make.
3650 ForLoop(loopinit,
3651 cond,
3652 List.of(step),
3653 body));
3654 patchTargets(body, tree, result);
3655 }
3656 /** Patch up break and continue targets. */
3657 private void patchTargets(JCTree body, final JCTree src, final JCTree dest) {
3658 class Patcher extends TreeScanner {
3659 public void visitBreak(JCBreak tree) {
3660 if (tree.target == src)
3661 tree.target = dest;
3662 }
3663 public void visitYield(JCYield tree) {
3664 if (tree.target == src)
3665 tree.target = dest;
3666 scan(tree.value);
3667 }
3668 public void visitContinue(JCContinue tree) {
3669 if (tree.target == src)
3670 tree.target = dest;
3671 }
3672 public void visitClassDef(JCClassDecl tree) {}
3673 }
3674 new Patcher().scan(body);
3675 }
3676 /**
3677 * A statement of the form
3678 *
3679 * <pre>
3680 * for ( T v : coll ) stmt ;
3681 * </pre>
3682 *
3683 * (where coll implements {@code Iterable<? extends T>}) gets translated to
3684 *
3685 * <pre>{@code
3686 * for ( Iterator<? extends T> #i = coll.iterator(); #i.hasNext(); ) {
3687 * T v = (T) #i.next();
3688 * stmt;
3689 * }
3690 * }</pre>
3691 *
3692 * where #i is a freshly named synthetic local variable.
3693 */
3694 private void visitIterableForeachLoop(JCEnhancedForLoop tree) {
3695 make_at(tree.expr.pos());
3696 Type iteratorTarget = syms.objectType;
3697 Type iterableType = types.asSuper(types.cvarUpperBound(tree.expr.type),
3698 syms.iterableType.tsym);
3699 if (iterableType.getTypeArguments().nonEmpty())
3700 iteratorTarget = types.erasure(iterableType.getTypeArguments().head);
3701 tree.expr.type = types.erasure(types.skipTypeVars(tree.expr.type, false));
3702 tree.expr = transTypes.coerce(attrEnv, tree.expr, types.erasure(iterableType));
3703 Symbol iterator = lookupMethod(tree.expr.pos(),
3704 names.iterator,
3705 tree.expr.type,
3706 List.nil());
3707 Assert.check(types.isSameType(types.erasure(types.asSuper(iterator.type.getReturnType(), syms.iteratorType.tsym)), types.erasure(syms.iteratorType)));
3708 VarSymbol itvar = new VarSymbol(SYNTHETIC, names.fromString("i" + target.syntheticNameChar()),
3709 types.erasure(syms.iteratorType),
3710 currentMethodSym);
3711
3712 JCStatement init = make.
3713 VarDef(itvar, make.App(make.Select(tree.expr, iterator)
3714 .setType(types.erasure(iterator.type))));
3715
3716 Symbol hasNext = lookupMethod(tree.expr.pos(),
3717 names.hasNext,
3718 itvar.type,
3719 List.nil());
3720 JCMethodInvocation cond = make.App(make.Select(make.Ident(itvar), hasNext));
3721 Symbol next = lookupMethod(tree.expr.pos(),
3722 names.next,
3723 itvar.type,
3724 List.nil());
3725 JCExpression vardefinit = make.App(make.Select(make.Ident(itvar), next));
3726 if (tree.var.type.isPrimitive())
3727 vardefinit = make.TypeCast(types.cvarUpperBound(iteratorTarget), vardefinit);
3728 else
3729 vardefinit = make.TypeCast(tree.var.type, vardefinit);
3730 JCVariableDecl indexDef = (JCVariableDecl)make.VarDef(tree.var.mods,
3731 tree.var.name,
3732 tree.var.vartype,
3733 vardefinit).setType(tree.var.type);
3734 indexDef.sym = tree.var.sym;
3735 JCBlock body = make.Block(0, List.of(indexDef, tree.body));
3736 body.bracePos = TreeInfo.endPos(tree.body);
3737 result = translate(make.
3738 ForLoop(List.of(init),
3739 cond,
3740 List.nil(),
3741 body));
3742 patchTargets(body, tree, result);
3743 }
3744
3745 public void visitVarDef(JCVariableDecl tree) {
3746 MethodSymbol oldMethodSym = currentMethodSym;
3747 int prevVariableIndex = variableIndex;
3748 tree.mods = translate(tree.mods);
3749 tree.vartype = translate(tree.vartype);
3750 if (currentMethodSym == null) {
3751 // A class or instance field initializer.
3752 currentMethodSym =
3753 new MethodSymbol((tree.mods.flags&STATIC) | BLOCK,
3754 names.empty, null,
3755 currentClass);
3756 }
3757 try {
3758 if (tree.init != null) tree.init = translate(tree.init, tree.type);
3759 result = tree;
3760 } finally {
3761 currentMethodSym = oldMethodSym;
3762 variableIndex = prevVariableIndex;
3763 }
3764 }
3765
3766 public void visitBlock(JCBlock tree) {
3767 MethodSymbol oldMethodSym = currentMethodSym;
3768 if (currentMethodSym == null) {
3769 // Block is a static or instance initializer.
3770 currentMethodSym =
3771 new MethodSymbol(tree.flags | BLOCK,
3772 names.empty, null,
3773 currentClass);
3774 }
3775 int prevVariableIndex = variableIndex;
3776 try {
3777 variableIndex = 0;
3778 super.visitBlock(tree);
3779 } finally {
3780 currentMethodSym = oldMethodSym;
3781 variableIndex = prevVariableIndex;
3782 }
3783 }
3784
3785 public void visitDoLoop(JCDoWhileLoop tree) {
3786 tree.body = translate(tree.body);
3787 tree.cond = translate(tree.cond, syms.booleanType);
3788 result = tree;
3789 }
3790
3791 public void visitWhileLoop(JCWhileLoop tree) {
3792 tree.cond = translate(tree.cond, syms.booleanType);
3793 tree.body = translate(tree.body);
3794 result = tree;
3795 }
3796
3797 public void visitForLoop(JCForLoop tree) {
3798 tree.init = translate(tree.init);
3799 if (tree.cond != null)
3800 tree.cond = translate(tree.cond, syms.booleanType);
3801 tree.step = translate(tree.step);
3802 tree.body = translate(tree.body);
3803 result = tree;
3804 }
3805
3806 public void visitReturn(JCReturn tree) {
3807 if (tree.expr != null)
3808 tree.expr = translate(tree.expr,
3809 currentRestype);
3810 result = tree;
3811 }
3812
3813 @Override
3814 public void visitLambda(JCLambda tree) {
3815 Type prevRestype = currentRestype;
3816 try {
3817 currentRestype = types.erasure(tree.getDescriptorType(types)).getReturnType();
3818 // represent void results as NO_TYPE, to avoid unnecessary boxing in boxIfNeeded
3819 if (currentRestype.hasTag(VOID))
3820 currentRestype = Type.noType;
3821 tree.body = tree.getBodyKind() == BodyKind.EXPRESSION ?
3822 translate((JCExpression) tree.body, currentRestype) :
3823 translate(tree.body);
3824 } finally {
3825 currentRestype = prevRestype;
3826 }
3827 result = tree;
3828 }
3829
3830 public void visitSwitch(JCSwitch tree) {
3831 List<JCCase> cases = tree.patternSwitch ? addDefaultIfNeeded(tree.patternSwitch,
3832 tree.wasEnumSelector,
3833 tree.cases)
3834 : tree.cases;
3835 handleSwitch(tree, tree.selector, cases);
3836 }
3837
3838 @Override
3839 public void visitSwitchExpression(JCSwitchExpression tree) {
3840 List<JCCase> cases = addDefaultIfNeeded(tree.patternSwitch, tree.wasEnumSelector, tree.cases);
3841 handleSwitch(tree, tree.selector, cases);
3842 }
3843
3844 private List<JCCase> addDefaultIfNeeded(boolean patternSwitch, boolean wasEnumSelector,
3845 List<JCCase> cases) {
3846 if (cases.stream().flatMap(c -> c.labels.stream()).noneMatch(p -> p.hasTag(Tag.DEFAULTCASELABEL))) {
3847 boolean matchException = useMatchException;
3848 matchException |= patternSwitch && !wasEnumSelector;
3849 Type exception = matchException ? syms.matchExceptionType
3850 : syms.incompatibleClassChangeErrorType;
3851 List<JCExpression> params = matchException ? List.of(makeNull(), makeNull())
3852 : List.nil();
3853 JCThrow thr = make.Throw(makeNewClass(exception, params));
3854 JCCase c = make.Case(JCCase.STATEMENT, List.of(make.DefaultCaseLabel()), null, List.of(thr), null);
3855 cases = cases.prepend(c);
3856 }
3857
3858 return cases;
3859 }
3860
3861 private void handleSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) {
3862 //expand multiple label cases:
3863 ListBuffer<JCCase> convertedCases = new ListBuffer<>();
3864
3865 for (JCCase c : cases) {
3866 switch (c.labels.size()) {
3867 case 0: //default
3868 case 1: //single label
3869 convertedCases.append(c);
3870 break;
3871 default: //multiple labels, expand:
3872 //case C1, C2, C3: ...
3873 //=>
3874 //case C1:
3875 //case C2:
3876 //case C3: ...
3877 List<JCCaseLabel> patterns = c.labels;
3878 while (patterns.tail.nonEmpty()) {
3879 convertedCases.append(make_at(c.pos()).Case(JCCase.STATEMENT,
3880 List.of(patterns.head),
3881 null,
3882 List.nil(),
3883 null));
3884 patterns = patterns.tail;
3885 }
3886 c.labels = patterns;
3887 convertedCases.append(c);
3888 break;
3889 }
3890 }
3891
3892 for (JCCase c : convertedCases) {
3893 if (c.caseKind == JCCase.RULE && c.completesNormally) {
3894 JCBreak b = make.at(TreeInfo.endPos(c.stats.last())).Break(null);
3895 b.target = tree;
3896 c.stats = c.stats.append(b);
3897 }
3898 }
3899
3900 cases = convertedCases.toList();
3901
3902 Type selsuper = types.supertype(selector.type);
3903 boolean enumSwitch = selsuper != null &&
3904 (selector.type.tsym.flags() & ENUM) != 0;
3905 boolean stringSwitch = selsuper != null &&
3906 types.isSameType(selector.type, syms.stringType);
3907 boolean boxedSwitch = !enumSwitch && !stringSwitch && !selector.type.isPrimitive();
3908 selector = translate(selector, selector.type);
3909 cases = translateCases(cases);
3910 if (tree.hasTag(SWITCH)) {
3911 ((JCSwitch) tree).selector = selector;
3912 ((JCSwitch) tree).cases = cases;
3913 } else if (tree.hasTag(SWITCH_EXPRESSION)) {
3914 ((JCSwitchExpression) tree).selector = selector;
3915 ((JCSwitchExpression) tree).cases = cases;
3916 } else {
3917 Assert.error();
3918 }
3919 if (enumSwitch) {
3920 result = visitEnumSwitch(tree, selector, cases);
3921 } else if (stringSwitch) {
3922 result = visitStringSwitch(tree, selector, cases);
3923 } else if (boxedSwitch) {
3924 //An switch over boxed primitive. Pattern matching switches are already translated
3925 //by TransPatterns, so all non-primitive types are only boxed primitives:
3926 result = visitBoxedPrimitiveSwitch(tree, selector, cases);
3927 } else {
3928 result = tree;
3929 }
3930 }
3931
3932 public JCTree visitEnumSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) {
3933 TypeSymbol enumSym = selector.type.tsym;
3934 EnumMapping map = mapForEnum(tree.pos(), enumSym);
3935 make_at(tree.pos());
3936 Symbol ordinalMethod = lookupMethod(tree.pos(),
3937 names.ordinal,
3938 selector.type,
3939 List.nil());
3940 JCExpression newSelector;
3941
3942 if (cases.stream().anyMatch(c -> TreeInfo.isNullCaseLabel(c.labels.head))) {
3943 //for enum switches with case null, do:
3944 //switch ($selector != null ? $mapVar[$selector.ordinal()] : -1) {...}
3945 //replacing case null with case -1:
3946 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC,
3947 names.fromString("s" + variableIndex++ + this.target.syntheticNameChar()),
3948 selector.type,
3949 currentMethodSym);
3950 JCStatement var = make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type);
3951 newSelector = map.switchValue(
3952 make.App(make.Select(make.Ident(dollar_s),
3953 ordinalMethod)));
3954 newSelector =
3955 make.LetExpr(List.of(var),
3956 make.Conditional(makeBinary(NE, make.Ident(dollar_s), makeNull()),
3957 newSelector,
3958 makeLit(syms.intType, -1))
3959 .setType(newSelector.type))
3960 .setType(newSelector.type);
3961 } else {
3962 newSelector = map.switchValue(
3963 make.App(make.Select(selector,
3964 ordinalMethod)));
3965 }
3966 ListBuffer<JCCase> newCases = new ListBuffer<>();
3967 for (JCCase c : cases) {
3968 if (c.labels.head.hasTag(CONSTANTCASELABEL)) {
3969 JCExpression pat;
3970 if (TreeInfo.isNullCaseLabel(c.labels.head)) {
3971 pat = makeLit(syms.intType, -1);
3972 } else {
3973 VarSymbol label = (VarSymbol)TreeInfo.symbol(((JCConstantCaseLabel) c.labels.head).expr);
3974 pat = map.caseValue(label);
3975 }
3976 newCases.append(make.Case(JCCase.STATEMENT, List.of(make.ConstantCaseLabel(pat)), null, c.stats, null));
3977 } else {
3978 newCases.append(c);
3979 }
3980 }
3981 JCTree enumSwitch;
3982 if (tree.hasTag(SWITCH)) {
3983 enumSwitch = make.Switch(newSelector, newCases.toList());
3984 } else if (tree.hasTag(SWITCH_EXPRESSION)) {
3985 enumSwitch = make.SwitchExpression(newSelector, newCases.toList());
3986 enumSwitch.setType(tree.type);
3987 } else {
3988 Assert.error();
3989 throw new AssertionError();
3990 }
3991 patchTargets(enumSwitch, tree, enumSwitch);
3992 return enumSwitch;
3993 }
3994
3995 public JCTree visitStringSwitch(JCTree tree, JCExpression selector, List<JCCase> caseList) {
3996 int alternatives = caseList.size();
3997
3998 if (alternatives == 0) { // Strange but legal possibility (only legal for switch statement)
3999 return make.at(tree.pos()).Exec(attr.makeNullCheck(selector));
4000 } else {
4001 /*
4002 * The general approach used is to translate a single
4003 * string switch statement into a series of two chained
4004 * switch statements: the first a synthesized statement
4005 * switching on the argument string's hash value and
4006 * computing a string's position in the list of original
4007 * case labels, if any, followed by a second switch on the
4008 * computed integer value. The second switch has the same
4009 * code structure as the original string switch statement
4010 * except that the string case labels are replaced with
4011 * positional integer constants starting at 0.
4012 *
4013 * The first switch statement can be thought of as an
4014 * inlined map from strings to their position in the case
4015 * label list. An alternate implementation would use an
4016 * actual Map for this purpose, as done for enum switches.
4017 *
4018 * With some additional effort, it would be possible to
4019 * use a single switch statement on the hash code of the
4020 * argument, but care would need to be taken to preserve
4021 * the proper control flow in the presence of hash
4022 * collisions and other complications, such as
4023 * fallthroughs. Switch statements with one or two
4024 * alternatives could also be specially translated into
4025 * if-then statements to omit the computation of the hash
4026 * code.
4027 *
4028 * The generated code assumes that the hashing algorithm
4029 * of String is the same in the compilation environment as
4030 * in the environment the code will run in. The string
4031 * hashing algorithm in the SE JDK has been unchanged
4032 * since at least JDK 1.2. Since the algorithm has been
4033 * specified since that release as well, it is very
4034 * unlikely to be changed in the future.
4035 *
4036 * Different hashing algorithms, such as the length of the
4037 * strings or a perfect hashing algorithm over the
4038 * particular set of case labels, could potentially be
4039 * used instead of String.hashCode.
4040 */
4041
4042 ListBuffer<JCStatement> stmtList = new ListBuffer<>();
4043
4044 // Map from String case labels to their original position in
4045 // the list of case labels.
4046 Map<String, Integer> caseLabelToPosition = new LinkedHashMap<>(alternatives + 1, 1.0f);
4047
4048 // Map of hash codes to the string case labels having that hashCode.
4049 Map<Integer, Set<String>> hashToString = new LinkedHashMap<>(alternatives + 1, 1.0f);
4050
4051 int casePosition = 0;
4052 JCCase nullCase = null;
4053 int nullCaseLabel = -1;
4054
4055 for(JCCase oneCase : caseList) {
4056 if (oneCase.labels.head.hasTag(CONSTANTCASELABEL)) {
4057 if (TreeInfo.isNullCaseLabel(oneCase.labels.head)) {
4058 nullCase = oneCase;
4059 nullCaseLabel = casePosition;
4060 } else {
4061 JCExpression expression = ((JCConstantCaseLabel) oneCase.labels.head).expr;
4062 String labelExpr = (String) expression.type.constValue();
4063 Integer mapping = caseLabelToPosition.put(labelExpr, casePosition);
4064 Assert.checkNull(mapping);
4065 int hashCode = labelExpr.hashCode();
4066
4067 Set<String> stringSet = hashToString.get(hashCode);
4068 if (stringSet == null) {
4069 stringSet = new LinkedHashSet<>(1, 1.0f);
4070 stringSet.add(labelExpr);
4071 hashToString.put(hashCode, stringSet);
4072 } else {
4073 boolean added = stringSet.add(labelExpr);
4074 Assert.check(added);
4075 }
4076 }
4077 }
4078 casePosition++;
4079 }
4080
4081 // Synthesize a switch statement that has the effect of
4082 // mapping from a string to the integer position of that
4083 // string in the list of case labels. This is done by
4084 // switching on the hashCode of the string followed by an
4085 // if-then-else chain comparing the input for equality
4086 // with all the case labels having that hash value.
4087
4088 /*
4089 * s$ = top of stack;
4090 * tmp$ = -1;
4091 * switch($s.hashCode()) {
4092 * case caseLabel.hashCode:
4093 * if (s$.equals("caseLabel_1")
4094 * tmp$ = caseLabelToPosition("caseLabel_1");
4095 * else if (s$.equals("caseLabel_2"))
4096 * tmp$ = caseLabelToPosition("caseLabel_2");
4097 * ...
4098 * break;
4099 * ...
4100 * }
4101 */
4102
4103 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC,
4104 names.fromString("s" + variableIndex++ + target.syntheticNameChar()),
4105 syms.stringType,
4106 currentMethodSym);
4107 stmtList.append(make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type));
4108
4109 VarSymbol dollar_tmp = new VarSymbol(SYNTHETIC,
4110 names.fromString("tmp" + variableIndex++ + target.syntheticNameChar()),
4111 syms.intType,
4112 currentMethodSym);
4113 JCVariableDecl dollar_tmp_def =
4114 (JCVariableDecl)make.VarDef(dollar_tmp, make.Literal(INT, -1)).setType(dollar_tmp.type);
4115 dollar_tmp_def.init.type = dollar_tmp.type = syms.intType;
4116 stmtList.append(dollar_tmp_def);
4117 ListBuffer<JCCase> caseBuffer = new ListBuffer<>();
4118 // hashCode will trigger nullcheck on original switch expression
4119 JCMethodInvocation hashCodeCall = makeCall(make.Ident(dollar_s),
4120 names.hashCode,
4121 List.nil()).setType(syms.intType);
4122 JCSwitch switch1 = make.Switch(hashCodeCall,
4123 caseBuffer.toList());
4124 for(Map.Entry<Integer, Set<String>> entry : hashToString.entrySet()) {
4125 int hashCode = entry.getKey();
4126 Set<String> stringsWithHashCode = entry.getValue();
4127 Assert.check(stringsWithHashCode.size() >= 1);
4128
4129 JCStatement elsepart = null;
4130 for(String caseLabel : stringsWithHashCode ) {
4131 JCMethodInvocation stringEqualsCall = makeCall(make.Ident(dollar_s),
4132 names.equals,
4133 List.of(make.Literal(caseLabel)));
4134 elsepart = make.If(stringEqualsCall,
4135 make.Exec(make.Assign(make.Ident(dollar_tmp),
4136 make.Literal(caseLabelToPosition.get(caseLabel))).
4137 setType(dollar_tmp.type)),
4138 elsepart);
4139 }
4140
4141 ListBuffer<JCStatement> lb = new ListBuffer<>();
4142 JCBreak breakStmt = make.Break(null);
4143 breakStmt.target = switch1;
4144 lb.append(elsepart).append(breakStmt);
4145
4146 caseBuffer.append(make.Case(JCCase.STATEMENT,
4147 List.of(make.ConstantCaseLabel(make.Literal(hashCode))),
4148 null,
4149 lb.toList(),
4150 null));
4151 }
4152
4153 switch1.cases = caseBuffer.toList();
4154
4155 if (nullCase != null) {
4156 stmtList.append(make.If(makeBinary(NE, make.Ident(dollar_s), makeNull()), switch1, make.Exec(make.Assign(make.Ident(dollar_tmp),
4157 make.Literal(nullCaseLabel)).
4158 setType(dollar_tmp.type))).setType(syms.intType));
4159 } else {
4160 stmtList.append(switch1);
4161 }
4162
4163 // Make isomorphic switch tree replacing string labels
4164 // with corresponding integer ones from the label to
4165 // position map.
4166
4167 ListBuffer<JCCase> lb = new ListBuffer<>();
4168 for(JCCase oneCase : caseList ) {
4169 boolean isDefault = !oneCase.labels.head.hasTag(CONSTANTCASELABEL);
4170 JCExpression caseExpr;
4171 if (isDefault)
4172 caseExpr = null;
4173 else if (oneCase == nullCase) {
4174 caseExpr = make.Literal(nullCaseLabel);
4175 } else {
4176 JCExpression expression = ((JCConstantCaseLabel) oneCase.labels.head).expr;
4177 String name = (String) TreeInfo.skipParens(expression)
4178 .type.constValue();
4179 caseExpr = make.Literal(caseLabelToPosition.get(name));
4180 }
4181
4182 lb.append(make.Case(JCCase.STATEMENT, caseExpr == null ? List.of(make.DefaultCaseLabel())
4183 : List.of(make.ConstantCaseLabel(caseExpr)),
4184 null,
4185 oneCase.stats, null));
4186 }
4187
4188 if (tree.hasTag(SWITCH)) {
4189 JCSwitch switch2 = make.Switch(make.Ident(dollar_tmp), lb.toList());
4190 // Rewire up old unlabeled break statements to the
4191 // replacement switch being created.
4192 patchTargets(switch2, tree, switch2);
4193
4194 stmtList.append(switch2);
4195
4196 JCBlock res = make.Block(0L, stmtList.toList());
4197 res.bracePos = TreeInfo.endPos(tree);
4198 return res;
4199 } else {
4200 JCSwitchExpression switch2 = make.SwitchExpression(make.Ident(dollar_tmp), lb.toList());
4201
4202 // Rewire up old unlabeled break statements to the
4203 // replacement switch being created.
4204 patchTargets(switch2, tree, switch2);
4205
4206 switch2.setType(tree.type);
4207
4208 LetExpr res = make.LetExpr(stmtList.toList(), switch2);
4209
4210 res.needsCond = true;
4211 res.setType(tree.type);
4212
4213 return res;
4214 }
4215 }
4216 }
4217
4218 private JCTree visitBoxedPrimitiveSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) {
4219 JCExpression newSelector;
4220
4221 if (cases.stream().anyMatch(c -> TreeInfo.isNullCaseLabel(c.labels.head))) {
4222 //a switch over a boxed primitive, with a null case. Pick two constants that are
4223 //not used by any branch in the case (c1 and c2), close to other constants that are
4224 //used in the switch. Then do:
4225 //switch ($selector != null ? $selector != c1 ? $selector : c2 : c1) {...}
4226 //replacing case null with case c1
4227 Set<Integer> constants = new LinkedHashSet<>();
4228 JCCase nullCase = null;
4229
4230 for (JCCase c : cases) {
4231 if (TreeInfo.isNullCaseLabel(c.labels.head)) {
4232 nullCase = c;
4233 } else if (!c.labels.head.hasTag(DEFAULTCASELABEL)) {
4234 constants.add((int) ((JCConstantCaseLabel) c.labels.head).expr.type.constValue());
4235 }
4236 }
4237
4238 Assert.checkNonNull(nullCase);
4239
4240 int nullValue = constants.isEmpty() ? 0 : constants.iterator().next();
4241
4242 while (constants.contains(nullValue)) nullValue++;
4243
4244 constants.add(nullValue);
4245 nullCase.labels.head = make.ConstantCaseLabel(makeLit(syms.intType, nullValue));
4246
4247 int replacementValue = nullValue;
4248
4249 while (constants.contains(replacementValue)) replacementValue++;
4250
4251 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC,
4252 names.fromString("s" + variableIndex++ + this.target.syntheticNameChar()),
4253 selector.type,
4254 currentMethodSym);
4255 JCStatement var = make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type);
4256 JCExpression nullValueReplacement =
4257 make.Conditional(makeBinary(NE,
4258 unbox(make.Ident(dollar_s), syms.intType),
4259 makeLit(syms.intType, nullValue)),
4260 unbox(make.Ident(dollar_s), syms.intType),
4261 makeLit(syms.intType, replacementValue))
4262 .setType(syms.intType);
4263 JCExpression nullCheck =
4264 make.Conditional(makeBinary(NE, make.Ident(dollar_s), makeNull()),
4265 nullValueReplacement,
4266 makeLit(syms.intType, nullValue))
4267 .setType(syms.intType);
4268 newSelector = make.LetExpr(List.of(var), nullCheck).setType(syms.intType);
4269 } else {
4270 newSelector = unbox(selector, syms.intType);
4271 }
4272
4273 if (tree.hasTag(SWITCH)) {
4274 ((JCSwitch) tree).selector = newSelector;
4275 } else {
4276 ((JCSwitchExpression) tree).selector = newSelector;
4277 }
4278
4279 return tree;
4280 }
4281
4282 @Override
4283 public void visitBreak(JCBreak tree) {
4284 result = tree;
4285 }
4286
4287 @Override
4288 public void visitYield(JCYield tree) {
4289 tree.value = translate(tree.value, tree.target.type);
4290 result = tree;
4291 }
4292
4293 public void visitNewArray(JCNewArray tree) {
4294 tree.elemtype = translate(tree.elemtype);
4295 for (List<JCExpression> t = tree.dims; t.tail != null; t = t.tail)
4296 if (t.head != null) t.head = translate(t.head, syms.intType);
4297 tree.elems = translate(tree.elems, types.elemtype(tree.type));
4298 result = tree;
4299 }
4300
4301 public void visitSelect(JCFieldAccess tree) {
4302 // need to special case-access of the form C.super.x
4303 // these will always need an access method, unless C
4304 // is a default interface subclassed by the current class.
4305 boolean qualifiedSuperAccess =
4306 tree.selected.hasTag(SELECT) &&
4307 TreeInfo.name(tree.selected) == names._super &&
4308 !types.isDirectSuperInterface(((JCFieldAccess)tree.selected).selected.type.tsym, currentClass);
4309 tree.selected = translate(tree.selected);
4310 if (tree.name == names._class && tree.selected.type.isPrimitiveOrVoid()) {
4311 result = classOf(tree.selected);
4312 }
4313 else if (tree.name == names._super &&
4314 types.isDirectSuperInterface(tree.selected.type.tsym, currentClass)) {
4315 //default super call!! Not a classic qualified super call
4316 TypeSymbol supSym = tree.selected.type.tsym;
4317 Assert.checkNonNull(types.asSuper(currentClass.type, supSym));
4318 result = tree;
4319 }
4320 else if (tree.name == names._this || tree.name == names._super) {
4321 result = makeThis(tree.pos(), tree.selected.type.tsym);
4322 }
4323 else
4324 result = access(tree.sym, tree, enclOp, qualifiedSuperAccess);
4325 }
4326
4327 public void visitLetExpr(LetExpr tree) {
4328 tree.defs = translate(tree.defs);
4329 tree.expr = translate(tree.expr, tree.type);
4330 result = tree;
4331 }
4332
4333 // There ought to be nothing to rewrite here;
4334 // we don't generate code.
4335 public void visitAnnotation(JCAnnotation tree) {
4336 result = tree;
4337 }
4338
4339 @Override
4340 public void visitTry(JCTry tree) {
4341 if (tree.resources.nonEmpty()) {
4342 result = makeTwrTry(tree);
4343 return;
4344 }
4345
4346 boolean hasBody = tree.body.getStatements().nonEmpty();
4347 boolean hasCatchers = tree.catchers.nonEmpty();
4348 boolean hasFinally = tree.finalizer != null &&
4349 tree.finalizer.getStatements().nonEmpty();
4350
4351 if (!hasCatchers && !hasFinally) {
4352 result = translate(tree.body);
4353 return;
4354 }
4355
4356 if (!hasBody) {
4357 if (hasFinally) {
4358 result = translate(tree.finalizer);
4359 } else {
4360 result = translate(tree.body);
4361 }
4362 return;
4363 }
4364
4365 // no optimizations possible
4366 super.visitTry(tree);
4367 }
4368
4369 /* ************************************************************************
4370 * main method
4371 *************************************************************************/
4372
4373 /** Translate a toplevel class and return a list consisting of
4374 * the translated class and translated versions of all inner classes.
4375 * @param env The attribution environment current at the class definition.
4376 * We need this for resolving some additional symbols.
4377 * @param cdef The tree representing the class definition.
4378 */
4379 public List<JCTree> translateTopLevelClass(Env<AttrContext> env, JCTree cdef, TreeMaker make) {
4380 ListBuffer<JCTree> translated = null;
4381 try {
4382 attrEnv = env;
4383 this.make = make;
4384 endPosTable = env.toplevel.endPositions;
4385 currentClass = null;
4386 currentRestype = null;
4387 currentMethodDef = null;
4388 outermostClassDef = (cdef.hasTag(CLASSDEF)) ? (JCClassDecl)cdef : null;
4389 outermostMemberDef = null;
4390 this.translated = new ListBuffer<>();
4391 classdefs = new HashMap<>();
4392 actualSymbols = new HashMap<>();
4393 freevarCache = new HashMap<>();
4394 proxies = new HashMap<>();
4395 twrVars = WriteableScope.create(syms.noSymbol);
4396 outerThisStack = List.nil();
4397 accessNums = new HashMap<>();
4398 accessSyms = new HashMap<>();
4399 accessConstrs = new HashMap<>();
4400 accessConstrTags = List.nil();
4401 accessed = new ListBuffer<>();
4402 translate(cdef, (JCExpression)null);
4403 for (List<Symbol> l = accessed.toList(); l.nonEmpty(); l = l.tail)
4404 makeAccessible(l.head);
4405 for (EnumMapping map : enumSwitchMap.values())
4406 map.translate();
4407 checkConflicts(this.translated.toList());
4408 checkAccessConstructorTags();
4409 translated = this.translated;
4410 } finally {
4411 // note that recursive invocations of this method fail hard
4412 attrEnv = null;
4413 this.make = null;
4414 endPosTable = null;
4415 currentClass = null;
4416 currentRestype = null;
4417 currentMethodDef = null;
4418 outermostClassDef = null;
4419 outermostMemberDef = null;
4420 this.translated = null;
4421 classdefs = null;
4422 actualSymbols = null;
4423 freevarCache = null;
4424 proxies = null;
4425 outerThisStack = null;
4426 accessNums = null;
4427 accessSyms = null;
4428 accessConstrs = null;
4429 accessConstrTags = null;
4430 accessed = null;
4431 enumSwitchMap.clear();
4432 assertionsDisabledClassCache = null;
4433 }
4434 return translated.toList();
4435 }
4436
4437 // needed for the lambda deserialization method, which is expressed as a big switch on strings
4438 public JCMethodDecl translateMethod(Env<AttrContext> env, JCMethodDecl methodDecl, TreeMaker make) {
4439 try {
4440 this.attrEnv = env;
4441 this.make = make;
4442 this.currentClass = methodDecl.sym.enclClass();
4443 proxies = new HashMap<>();
4444 return translate(methodDecl);
4445 } finally {
4446 this.attrEnv = null;
4447 this.make = null;
4448 this.currentClass = null;
4449 // the two fields below are set when visiting the method
4450 this.currentMethodSym = null;
4451 this.currentMethodDef = null;
4452 this.proxies = null;
4453 }
4454 }
4455 }