1 /*
2 * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.javac.jvm;
27
28 import java.util.HashMap;
29 import java.util.Map;
30 import java.util.Set;
31
32 import com.sun.tools.javac.jvm.PoolConstant.LoadableConstant;
33 import com.sun.tools.javac.tree.TreeInfo.PosKind;
34 import com.sun.tools.javac.util.*;
35 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
36 import com.sun.tools.javac.util.List;
37 import com.sun.tools.javac.code.*;
38 import com.sun.tools.javac.code.Attribute.TypeCompound;
39 import com.sun.tools.javac.code.Symbol.VarSymbol;
40 import com.sun.tools.javac.comp.*;
41 import com.sun.tools.javac.tree.*;
42
43 import com.sun.tools.javac.code.Symbol.*;
44 import com.sun.tools.javac.code.Type.*;
45 import com.sun.tools.javac.jvm.Code.*;
46 import com.sun.tools.javac.jvm.Items.*;
47 import com.sun.tools.javac.resources.CompilerProperties.Errors;
48 import com.sun.tools.javac.tree.EndPosTable;
49 import com.sun.tools.javac.tree.JCTree.*;
50
51 import static com.sun.tools.javac.code.Flags.*;
52 import static com.sun.tools.javac.code.Kinds.Kind.*;
53 import static com.sun.tools.javac.code.TypeTag.*;
54 import static com.sun.tools.javac.jvm.ByteCodes.*;
55 import static com.sun.tools.javac.jvm.CRTFlags.*;
56 import static com.sun.tools.javac.main.Option.*;
57 import static com.sun.tools.javac.tree.JCTree.Tag.*;
58
59 /** This pass maps flat Java (i.e. without inner classes) to bytecodes.
60 *
61 * <p><b>This is NOT part of any supported API.
62 * If you write code that depends on this, you do so at your own risk.
63 * This code and its internal interfaces are subject to change or
64 * deletion without notice.</b>
65 */
66 public class Gen extends JCTree.Visitor {
67 protected static final Context.Key<Gen> genKey = new Context.Key<>();
68
69 private final Log log;
70 private final Symtab syms;
71 private final Check chk;
72 private final Resolve rs;
73 private final TreeMaker make;
74 private final Names names;
75 private final Target target;
76 private final String accessDollar;
77 private final Types types;
78 private final Lower lower;
79 private final Annotate annotate;
80 private final StringConcat concat;
81
82 /** Format of stackmap tables to be generated. */
83 private final Code.StackMapFormat stackMap;
84
85 /** A type that serves as the expected type for all method expressions.
86 */
87 private final Type methodType;
88
89 public static Gen instance(Context context) {
90 Gen instance = context.get(genKey);
91 if (instance == null)
92 instance = new Gen(context);
93 return instance;
94 }
95
96 /** Constant pool writer, set by genClass.
97 */
98 final PoolWriter poolWriter;
99
100 private final UnsetFieldsInfo unsetFieldsInfo;
101
102 @SuppressWarnings("this-escape")
103 protected Gen(Context context) {
104 context.put(genKey, this);
105
106 names = Names.instance(context);
107 log = Log.instance(context);
108 syms = Symtab.instance(context);
109 chk = Check.instance(context);
110 rs = Resolve.instance(context);
111 make = TreeMaker.instance(context);
112 target = Target.instance(context);
113 types = Types.instance(context);
114 concat = StringConcat.instance(context);
115
116 methodType = new MethodType(null, null, null, syms.methodClass);
117 accessDollar = "access" + target.syntheticNameChar();
118 lower = Lower.instance(context);
119
120 Options options = Options.instance(context);
121 lineDebugInfo =
122 options.isUnset(G_CUSTOM) ||
123 options.isSet(G_CUSTOM, "lines");
124 varDebugInfo =
125 options.isUnset(G_CUSTOM)
126 ? options.isSet(G)
127 : options.isSet(G_CUSTOM, "vars");
128 genCrt = options.isSet(XJCOV);
129 debugCode = options.isSet("debug.code");
130 disableVirtualizedPrivateInvoke = options.isSet("disableVirtualizedPrivateInvoke");
131 poolWriter = new PoolWriter(types, names);
132 unsetFieldsInfo = UnsetFieldsInfo.instance(context);
133
134 // ignore cldc because we cannot have both stackmap formats
135 this.stackMap = StackMapFormat.JSR202;
136 annotate = Annotate.instance(context);
137 qualifiedSymbolCache = new HashMap<>();
138 generateEarlyLarvalFrame = options.isSet("generateEarlyLarvalFrame");
139 Preview preview = Preview.instance(context);
140 Source source = Source.instance(context);
141 allowValueClasses = (!preview.isPreview(Source.Feature.VALUE_CLASSES) || preview.isEnabled()) &&
142 Source.Feature.VALUE_CLASSES.allowedInSource(source);
143 }
144
145 /** Switches
146 */
147 private final boolean lineDebugInfo;
148 private final boolean varDebugInfo;
149 private final boolean genCrt;
150 private final boolean debugCode;
151 private boolean disableVirtualizedPrivateInvoke;
152 private boolean generateEarlyLarvalFrame;
153 private final boolean allowValueClasses;
154
155 /** Code buffer, set by genMethod.
156 */
157 private Code code;
158
159 /** Items structure, set by genMethod.
160 */
161 private Items items;
162
163 /** Environment for symbol lookup, set by genClass
164 */
165 private Env<AttrContext> attrEnv;
166
167 /** The top level tree.
168 */
169 private JCCompilationUnit toplevel;
170
171 /** The number of code-gen errors in this class.
172 */
173 private int nerrs = 0;
174
175 /** An object containing mappings of syntax trees to their
176 * ending source positions.
177 */
178 EndPosTable endPosTable;
179
180 boolean inCondSwitchExpression;
181 Chain switchExpressionTrueChain;
182 Chain switchExpressionFalseChain;
183 List<LocalItem> stackBeforeSwitchExpression;
184 LocalItem switchResult;
185 PatternMatchingCatchConfiguration patternMatchingCatchConfiguration =
186 new PatternMatchingCatchConfiguration(Set.of(), null, null, null);
187
188 /** Cache the symbol to reflect the qualifying type.
189 * key: corresponding type
190 * value: qualified symbol
191 */
192 Map<Type, Symbol> qualifiedSymbolCache;
193
194 /** Generate code to load an integer constant.
195 * @param n The integer to be loaded.
196 */
197 void loadIntConst(int n) {
198 items.makeImmediateItem(syms.intType, n).load();
199 }
200
201 /** The opcode that loads a zero constant of a given type code.
202 * @param tc The given type code (@see ByteCode).
203 */
204 public static int zero(int tc) {
205 switch(tc) {
206 case INTcode: case BYTEcode: case SHORTcode: case CHARcode:
207 return iconst_0;
208 case LONGcode:
209 return lconst_0;
210 case FLOATcode:
211 return fconst_0;
212 case DOUBLEcode:
213 return dconst_0;
214 default:
215 throw new AssertionError("zero");
216 }
217 }
218
219 /** The opcode that loads a one constant of a given type code.
220 * @param tc The given type code (@see ByteCode).
221 */
222 public static int one(int tc) {
223 return zero(tc) + 1;
224 }
225
226 /** Generate code to load -1 of the given type code (either int or long).
227 * @param tc The given type code (@see ByteCode).
228 */
229 void emitMinusOne(int tc) {
230 if (tc == LONGcode) {
231 items.makeImmediateItem(syms.longType, Long.valueOf(-1)).load();
232 } else {
233 code.emitop0(iconst_m1);
234 }
235 }
236
237 /** Construct a symbol to reflect the qualifying type that should
238 * appear in the byte code as per JLS 13.1.
239 *
240 * For {@literal target >= 1.2}: Clone a method with the qualifier as owner (except
241 * for those cases where we need to work around VM bugs).
242 *
243 * For {@literal target <= 1.1}: If qualified variable or method is defined in a
244 * non-accessible class, clone it with the qualifier class as owner.
245 *
246 * @param sym The accessed symbol
247 * @param site The qualifier's type.
248 */
249 Symbol binaryQualifier(Symbol sym, Type site) {
250
251 if (site.hasTag(ARRAY)) {
252 if (sym == syms.lengthVar ||
253 sym.owner != syms.arrayClass)
254 return sym;
255 // array clone can be qualified by the array type in later targets
256 Symbol qualifier;
257 if ((qualifier = qualifiedSymbolCache.get(site)) == null) {
258 qualifier = new ClassSymbol(Flags.PUBLIC, site.tsym.name, site, syms.noSymbol);
259 qualifiedSymbolCache.put(site, qualifier);
260 }
261 return sym.clone(qualifier);
262 }
263
264 if (sym.owner == site.tsym ||
265 (sym.flags() & (STATIC | SYNTHETIC)) == (STATIC | SYNTHETIC)) {
266 return sym;
267 }
268
269 // leave alone methods inherited from Object
270 // JLS 13.1.
271 if (sym.owner == syms.objectType.tsym)
272 return sym;
273
274 return sym.clone(site.tsym);
275 }
276
277 /** Insert a reference to given type in the constant pool,
278 * checking for an array with too many dimensions;
279 * return the reference's index.
280 * @param type The type for which a reference is inserted.
281 */
282 int makeRef(DiagnosticPosition pos, Type type) {
283 return poolWriter.putClass(checkDimension(pos, type));
284 }
285
286 /** Check if the given type is an array with too many dimensions.
287 */
288 private Type checkDimension(DiagnosticPosition pos, Type t) {
289 checkDimensionInternal(pos, t);
290 return t;
291 }
292
293 private void checkDimensionInternal(DiagnosticPosition pos, Type t) {
294 switch (t.getTag()) {
295 case METHOD:
296 checkDimension(pos, t.getReturnType());
297 for (List<Type> args = t.getParameterTypes(); args.nonEmpty(); args = args.tail)
298 checkDimension(pos, args.head);
299 break;
300 case ARRAY:
301 if (types.dimensions(t) > ClassFile.MAX_DIMENSIONS) {
302 log.error(pos, Errors.LimitDimensions);
303 nerrs++;
304 }
305 break;
306 default:
307 break;
308 }
309 }
310
311 /** Create a temporary variable.
312 * @param type The variable's type.
313 */
314 LocalItem makeTemp(Type type) {
315 VarSymbol v = new VarSymbol(Flags.SYNTHETIC,
316 names.empty,
317 type,
318 env.enclMethod.sym);
319 code.newLocal(v);
320 return items.makeLocalItem(v);
321 }
322
323 /** Generate code to call a non-private method or constructor.
324 * @param pos Position to be used for error reporting.
325 * @param site The type of which the method is a member.
326 * @param name The method's name.
327 * @param argtypes The method's argument types.
328 * @param isStatic A flag that indicates whether we call a
329 * static or instance method.
330 */
331 void callMethod(DiagnosticPosition pos,
332 Type site, Name name, List<Type> argtypes,
333 boolean isStatic) {
334 Symbol msym = rs.
335 resolveInternalMethod(pos, attrEnv, site, name, argtypes, null);
336 if (isStatic) items.makeStaticItem(msym).invoke();
337 else items.makeMemberItem(msym, name == names.init).invoke();
338 }
339
340 /** Is the given method definition an access method
341 * resulting from a qualified super? This is signified by an odd
342 * access code.
343 */
344 private boolean isAccessSuper(JCMethodDecl enclMethod) {
345 return
346 (enclMethod.mods.flags & SYNTHETIC) != 0 &&
347 isOddAccessName(enclMethod.name);
348 }
349
350 /** Does given name start with "access$" and end in an odd digit?
351 */
352 private boolean isOddAccessName(Name name) {
353 final String string = name.toString();
354 return
355 string.startsWith(accessDollar) &&
356 (string.charAt(string.length() - 1) & 1) != 0;
357 }
358
359 /* ************************************************************************
360 * Non-local exits
361 *************************************************************************/
362
363 /** Generate code to invoke the finalizer associated with given
364 * environment.
365 * Any calls to finalizers are appended to the environments `cont' chain.
366 * Mark beginning of gap in catch all range for finalizer.
367 */
368 void genFinalizer(Env<GenContext> env) {
369 if (code.isAlive() && env.info.finalize != null)
370 env.info.finalize.gen();
371 }
372
373 /** Generate code to call all finalizers of structures aborted by
374 * a non-local
375 * exit. Return target environment of the non-local exit.
376 * @param target The tree representing the structure that's aborted
377 * @param env The environment current at the non-local exit.
378 */
379 Env<GenContext> unwind(JCTree target, Env<GenContext> env) {
380 Env<GenContext> env1 = env;
381 while (true) {
382 genFinalizer(env1);
383 if (env1.tree == target) break;
384 env1 = env1.next;
385 }
386 return env1;
387 }
388
389 /** Mark end of gap in catch-all range for finalizer.
390 * @param env the environment which might contain the finalizer
391 * (if it does, env.info.gaps != null).
392 */
393 void endFinalizerGap(Env<GenContext> env) {
394 if (env.info.gaps != null && env.info.gaps.length() % 2 == 1)
395 env.info.gaps.append(code.curCP());
396 }
397
398 /** Mark end of all gaps in catch-all ranges for finalizers of environments
399 * lying between, and including to two environments.
400 * @param from the most deeply nested environment to mark
401 * @param to the least deeply nested environment to mark
402 */
403 void endFinalizerGaps(Env<GenContext> from, Env<GenContext> to) {
404 Env<GenContext> last = null;
405 while (last != to) {
406 endFinalizerGap(from);
407 last = from;
408 from = from.next;
409 }
410 }
411
412 /** Do any of the structures aborted by a non-local exit have
413 * finalizers that require an empty stack?
414 * @param target The tree representing the structure that's aborted
415 * @param env The environment current at the non-local exit.
416 */
417 boolean hasFinally(JCTree target, Env<GenContext> env) {
418 while (env.tree != target) {
419 if (env.tree.hasTag(TRY) && env.info.finalize.hasFinalizer())
420 return true;
421 env = env.next;
422 }
423 return false;
424 }
425
426 /* ************************************************************************
427 * Normalizing class-members.
428 *************************************************************************/
429
430 /** Distribute member initializer code into constructors and {@code <clinit>}
431 * method.
432 * @param defs The list of class member declarations.
433 * @param c The enclosing class.
434 */
435 List<JCTree> normalizeDefs(List<JCTree> defs, ClassSymbol c) {
436 ListBuffer<JCStatement> initCode = new ListBuffer<>();
437 // only used for value classes
438 ListBuffer<JCStatement> initBlocks = new ListBuffer<>();
439 ListBuffer<Attribute.TypeCompound> initTAs = new ListBuffer<>();
440 ListBuffer<JCStatement> clinitCode = new ListBuffer<>();
441 ListBuffer<Attribute.TypeCompound> clinitTAs = new ListBuffer<>();
442 ListBuffer<JCTree> methodDefs = new ListBuffer<>();
443 // Sort definitions into three listbuffers:
444 // - initCode for instance initializers
445 // - clinitCode for class initializers
446 // - methodDefs for method definitions
447 for (List<JCTree> l = defs; l.nonEmpty(); l = l.tail) {
448 JCTree def = l.head;
449 switch (def.getTag()) {
450 case BLOCK:
451 JCBlock block = (JCBlock)def;
452 if ((block.flags & STATIC) != 0)
453 clinitCode.append(block);
454 else if ((block.flags & SYNTHETIC) == 0) {
455 if (c.isValueClass() || c.hasStrict()) {
456 initBlocks.append(block);
457 } else {
458 initCode.append(block);
459 }
460 }
461 break;
462 case METHODDEF:
463 methodDefs.append(def);
464 break;
465 case VARDEF:
466 JCVariableDecl vdef = (JCVariableDecl) def;
467 VarSymbol sym = vdef.sym;
468 checkDimension(vdef.pos(), sym.type);
469 if (vdef.init != null) {
470 if ((sym.flags() & STATIC) == 0) {
471 // Always initialize instance variables.
472 JCStatement init = make.at(vdef.pos()).
473 Assignment(sym, vdef.init);
474 initCode.append(init);
475 endPosTable.replaceTree(vdef, init);
476 initTAs.addAll(getAndRemoveNonFieldTAs(sym));
477 } else if (sym.getConstValue() == null) {
478 // Initialize class (static) variables only if
479 // they are not compile-time constants.
480 JCStatement init = make.at(vdef.pos).
481 Assignment(sym, vdef.init);
482 clinitCode.append(init);
483 endPosTable.replaceTree(vdef, init);
484 clinitTAs.addAll(getAndRemoveNonFieldTAs(sym));
485 } else {
486 checkStringConstant(vdef.init.pos(), sym.getConstValue());
487 /* if the init contains a reference to an external class, add it to the
488 * constant's pool
489 */
490 vdef.init.accept(classReferenceVisitor);
491 }
492 }
493 break;
494 default:
495 Assert.error();
496 }
497 }
498 // Insert any instance initializers into all constructors.
499 if (initCode.length() != 0 || initBlocks.length() != 0) {
500 initTAs.addAll(c.getInitTypeAttributes());
501 List<Attribute.TypeCompound> initTAlist = initTAs.toList();
502 for (JCTree t : methodDefs) {
503 normalizeMethod((JCMethodDecl)t, initCode.toList(), initBlocks.toList(), initTAlist);
504 }
505 }
506 // If there are class initializers, create a <clinit> method
507 // that contains them as its body.
508 if (clinitCode.length() != 0) {
509 MethodSymbol clinit = new MethodSymbol(
510 STATIC | (c.flags() & STRICTFP),
511 names.clinit,
512 new MethodType(
513 List.nil(), syms.voidType,
514 List.nil(), syms.methodClass),
515 c);
516 c.members().enter(clinit);
517 List<JCStatement> clinitStats = clinitCode.toList();
518 JCBlock block = make.at(clinitStats.head.pos()).Block(0, clinitStats);
519 block.endpos = TreeInfo.endPos(clinitStats.last());
520 methodDefs.append(make.MethodDef(clinit, block));
521
522 if (!clinitTAs.isEmpty())
523 clinit.appendUniqueTypeAttributes(clinitTAs.toList());
524 if (!c.getClassInitTypeAttributes().isEmpty())
525 clinit.appendUniqueTypeAttributes(c.getClassInitTypeAttributes());
526 }
527 // Return all method definitions.
528 return methodDefs.toList();
529 }
530
531 private List<Attribute.TypeCompound> getAndRemoveNonFieldTAs(VarSymbol sym) {
532 List<TypeCompound> tas = sym.getRawTypeAttributes();
533 ListBuffer<Attribute.TypeCompound> fieldTAs = new ListBuffer<>();
534 ListBuffer<Attribute.TypeCompound> nonfieldTAs = new ListBuffer<>();
535 for (TypeCompound ta : tas) {
536 Assert.check(ta.getPosition().type != TargetType.UNKNOWN);
537 if (ta.getPosition().type == TargetType.FIELD) {
538 fieldTAs.add(ta);
539 } else {
540 nonfieldTAs.add(ta);
541 }
542 }
543 sym.setTypeAttributes(fieldTAs.toList());
544 return nonfieldTAs.toList();
545 }
546
547 /** Check a constant value and report if it is a string that is
548 * too large.
549 */
550 private void checkStringConstant(DiagnosticPosition pos, Object constValue) {
551 if (nerrs != 0 || // only complain about a long string once
552 constValue == null ||
553 !(constValue instanceof String str) ||
554 str.length() < PoolWriter.MAX_STRING_LENGTH)
555 return;
556 log.error(pos, Errors.LimitString);
557 nerrs++;
558 }
559
560 /** Insert instance initializer code into constructors prior to the super() call.
561 * @param md The tree potentially representing a
562 * constructor's definition.
563 * @param initCode The list of instance initializer statements.
564 * @param initTAs Type annotations from the initializer expression.
565 */
566 void normalizeMethod(JCMethodDecl md, List<JCStatement> initCode, List<JCStatement> initBlocks, List<TypeCompound> initTAs) {
567 if (TreeInfo.isConstructor(md) && TreeInfo.hasConstructorCall(md, names._super)) {
568 // We are seeing a constructor that has a super() call.
569 // Find the super() invocation and append the given initializer code.
570 if (allowValueClasses & (md.sym.owner.isValueClass() || md.sym.owner.hasStrict() || ((md.sym.owner.flags_field & RECORD) != 0))) {
571 rewriteInitializersIfNeeded(md, initCode);
572 md.body.stats = initCode.appendList(md.body.stats);
573 TreeInfo.mapSuperCalls(md.body, supercall -> make.Block(0, initBlocks.prepend(supercall)));
574 } else {
575 TreeInfo.mapSuperCalls(md.body, supercall -> make.Block(0, initCode.prepend(supercall)));
576 }
577
578 if (md.body.endpos == Position.NOPOS)
579 md.body.endpos = TreeInfo.endPos(md.body.stats.last());
580
581 md.sym.appendUniqueTypeAttributes(initTAs);
582 }
583 }
584
585 void rewriteInitializersIfNeeded(JCMethodDecl md, List<JCStatement> initCode) {
586 if (lower.initializerOuterThis.containsKey(md.sym.owner)) {
587 InitializerVisitor initializerVisitor = new InitializerVisitor(md, lower.initializerOuterThis.get(md.sym.owner));
588 for (JCStatement init : initCode) {
589 initializerVisitor.scan(init);
590 }
591 }
592 }
593
594 public static class InitializerVisitor extends TreeScanner {
595 JCMethodDecl md;
596 Set<JCExpression> exprSet;
597
598 public InitializerVisitor(JCMethodDecl md, Set<JCExpression> exprSet) {
599 this.md = md;
600 this.exprSet = exprSet;
601 }
602
603 @Override
604 public void visitTree(JCTree tree) {}
605
606 @Override
607 public void visitIdent(JCIdent tree) {
608 if (exprSet.contains(tree)) {
609 for (JCVariableDecl param: md.params) {
610 if (param.name == tree.name &&
611 ((param.sym.flags_field & (MANDATED | NOOUTERTHIS)) == (MANDATED | NOOUTERTHIS))) {
612 tree.sym = param.sym;
613 }
614 }
615 }
616 }
617 }
618
619 /* ************************************************************************
620 * Traversal methods
621 *************************************************************************/
622
623 /** Visitor argument: The current environment.
624 */
625 Env<GenContext> env;
626
627 /** Visitor argument: The expected type (prototype).
628 */
629 Type pt;
630
631 /** Visitor result: The item representing the computed value.
632 */
633 Item result;
634
635 /** Visitor method: generate code for a definition, catching and reporting
636 * any completion failures.
637 * @param tree The definition to be visited.
638 * @param env The environment current at the definition.
639 */
640 public void genDef(JCTree tree, Env<GenContext> env) {
641 Env<GenContext> prevEnv = this.env;
642 try {
643 this.env = env;
644 tree.accept(this);
645 } catch (CompletionFailure ex) {
646 chk.completionError(tree.pos(), ex);
647 } finally {
648 this.env = prevEnv;
649 }
650 }
651
652 /** Derived visitor method: check whether CharacterRangeTable
653 * should be emitted, if so, put a new entry into CRTable
654 * and call method to generate bytecode.
655 * If not, just call method to generate bytecode.
656 * @see #genStat(JCTree, Env)
657 *
658 * @param tree The tree to be visited.
659 * @param env The environment to use.
660 * @param crtFlags The CharacterRangeTable flags
661 * indicating type of the entry.
662 */
663 public void genStat(JCTree tree, Env<GenContext> env, int crtFlags) {
664 if (!genCrt) {
665 genStat(tree, env);
666 return;
667 }
668 int startpc = code.curCP();
669 genStat(tree, env);
670 if (tree.hasTag(Tag.BLOCK)) crtFlags |= CRT_BLOCK;
671 code.crt.put(tree, crtFlags, startpc, code.curCP());
672 }
673
674 /** Derived visitor method: generate code for a statement.
675 */
676 public void genStat(JCTree tree, Env<GenContext> env) {
677 if (code.isAlive()) {
678 code.statBegin(tree.pos);
679 genDef(tree, env);
680 } else if (env.info.isSwitch && tree.hasTag(VARDEF)) {
681 // variables whose declarations are in a switch
682 // can be used even if the decl is unreachable.
683 code.newLocal(((JCVariableDecl) tree).sym);
684 }
685 }
686
687 /** Derived visitor method: check whether CharacterRangeTable
688 * should be emitted, if so, put a new entry into CRTable
689 * and call method to generate bytecode.
690 * If not, just call method to generate bytecode.
691 * @see #genStats(List, Env)
692 *
693 * @param trees The list of trees to be visited.
694 * @param env The environment to use.
695 * @param crtFlags The CharacterRangeTable flags
696 * indicating type of the entry.
697 */
698 public void genStats(List<JCStatement> trees, Env<GenContext> env, int crtFlags) {
699 if (!genCrt) {
700 genStats(trees, env);
701 return;
702 }
703 if (trees.length() == 1) { // mark one statement with the flags
704 genStat(trees.head, env, crtFlags | CRT_STATEMENT);
705 } else {
706 int startpc = code.curCP();
707 genStats(trees, env);
708 code.crt.put(trees, crtFlags, startpc, code.curCP());
709 }
710 }
711
712 /** Derived visitor method: generate code for a list of statements.
713 */
714 public void genStats(List<? extends JCTree> trees, Env<GenContext> env) {
715 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
716 genStat(l.head, env, CRT_STATEMENT);
717 }
718
719 /** Derived visitor method: check whether CharacterRangeTable
720 * should be emitted, if so, put a new entry into CRTable
721 * and call method to generate bytecode.
722 * If not, just call method to generate bytecode.
723 * @see #genCond(JCTree,boolean)
724 *
725 * @param tree The tree to be visited.
726 * @param crtFlags The CharacterRangeTable flags
727 * indicating type of the entry.
728 */
729 public CondItem genCond(JCTree tree, int crtFlags) {
730 if (!genCrt) return genCond(tree, false);
731 int startpc = code.curCP();
732 CondItem item = genCond(tree, (crtFlags & CRT_FLOW_CONTROLLER) != 0);
733 code.crt.put(tree, crtFlags, startpc, code.curCP());
734 return item;
735 }
736
737 /** Derived visitor method: generate code for a boolean
738 * expression in a control-flow context.
739 * @param _tree The expression to be visited.
740 * @param markBranches The flag to indicate that the condition is
741 * a flow controller so produced conditions
742 * should contain a proper tree to generate
743 * CharacterRangeTable branches for them.
744 */
745 public CondItem genCond(JCTree _tree, boolean markBranches) {
746 JCTree inner_tree = TreeInfo.skipParens(_tree);
747 if (inner_tree.hasTag(CONDEXPR)) {
748 JCConditional tree = (JCConditional)inner_tree;
749 CondItem cond = genCond(tree.cond, CRT_FLOW_CONTROLLER);
750 if (cond.isTrue()) {
751 code.resolve(cond.trueJumps);
752 CondItem result = genCond(tree.truepart, CRT_FLOW_TARGET);
753 if (markBranches) result.tree = tree.truepart;
754 return result;
755 }
756 if (cond.isFalse()) {
757 code.resolve(cond.falseJumps);
758 CondItem result = genCond(tree.falsepart, CRT_FLOW_TARGET);
759 if (markBranches) result.tree = tree.falsepart;
760 return result;
761 }
762 Chain secondJumps = cond.jumpFalse();
763 code.resolve(cond.trueJumps);
764 CondItem first = genCond(tree.truepart, CRT_FLOW_TARGET);
765 if (markBranches) first.tree = tree.truepart;
766 Chain falseJumps = first.jumpFalse();
767 code.resolve(first.trueJumps);
768 Chain trueJumps = code.branch(goto_);
769 code.resolve(secondJumps);
770 CondItem second = genCond(tree.falsepart, CRT_FLOW_TARGET);
771 CondItem result = items.makeCondItem(second.opcode,
772 Code.mergeChains(trueJumps, second.trueJumps),
773 Code.mergeChains(falseJumps, second.falseJumps));
774 if (markBranches) result.tree = tree.falsepart;
775 return result;
776 } else if (inner_tree.hasTag(SWITCH_EXPRESSION)) {
777 code.resolvePending();
778
779 boolean prevInCondSwitchExpression = inCondSwitchExpression;
780 Chain prevSwitchExpressionTrueChain = switchExpressionTrueChain;
781 Chain prevSwitchExpressionFalseChain = switchExpressionFalseChain;
782 try {
783 inCondSwitchExpression = true;
784 switchExpressionTrueChain = null;
785 switchExpressionFalseChain = null;
786 try {
787 doHandleSwitchExpression((JCSwitchExpression) inner_tree);
788 } catch (CompletionFailure ex) {
789 chk.completionError(_tree.pos(), ex);
790 code.state.stacksize = 1;
791 }
792 CondItem result = items.makeCondItem(goto_,
793 switchExpressionTrueChain,
794 switchExpressionFalseChain);
795 if (markBranches) result.tree = _tree;
796 return result;
797 } finally {
798 inCondSwitchExpression = prevInCondSwitchExpression;
799 switchExpressionTrueChain = prevSwitchExpressionTrueChain;
800 switchExpressionFalseChain = prevSwitchExpressionFalseChain;
801 }
802 } else if (inner_tree.hasTag(LETEXPR) && ((LetExpr) inner_tree).needsCond) {
803 code.resolvePending();
804
805 LetExpr tree = (LetExpr) inner_tree;
806 int limit = code.nextreg;
807 int prevLetExprStart = code.setLetExprStackPos(code.state.stacksize);
808 try {
809 genStats(tree.defs, env);
810 } finally {
811 code.setLetExprStackPos(prevLetExprStart);
812 }
813 CondItem result = genCond(tree.expr, markBranches);
814 code.endScopes(limit);
815 return result;
816 } else {
817 CondItem result = genExpr(_tree, syms.booleanType).mkCond();
818 if (markBranches) result.tree = _tree;
819 return result;
820 }
821 }
822
823 public Code getCode() {
824 return code;
825 }
826
827 public Items getItems() {
828 return items;
829 }
830
831 public Env<AttrContext> getAttrEnv() {
832 return attrEnv;
833 }
834
835 /** Visitor class for expressions which might be constant expressions.
836 * This class is a subset of TreeScanner. Intended to visit trees pruned by
837 * Lower as long as constant expressions looking for references to any
838 * ClassSymbol. Any such reference will be added to the constant pool so
839 * automated tools can detect class dependencies better.
840 */
841 class ClassReferenceVisitor extends JCTree.Visitor {
842
843 @Override
844 public void visitTree(JCTree tree) {}
845
846 @Override
847 public void visitBinary(JCBinary tree) {
848 tree.lhs.accept(this);
849 tree.rhs.accept(this);
850 }
851
852 @Override
853 public void visitSelect(JCFieldAccess tree) {
854 if (tree.selected.type.hasTag(CLASS)) {
855 makeRef(tree.selected.pos(), tree.selected.type);
856 }
857 }
858
859 @Override
860 public void visitIdent(JCIdent tree) {
861 if (tree.sym.owner instanceof ClassSymbol classSymbol) {
862 poolWriter.putClass(classSymbol);
863 }
864 }
865
866 @Override
867 public void visitConditional(JCConditional tree) {
868 tree.cond.accept(this);
869 tree.truepart.accept(this);
870 tree.falsepart.accept(this);
871 }
872
873 @Override
874 public void visitUnary(JCUnary tree) {
875 tree.arg.accept(this);
876 }
877
878 @Override
879 public void visitParens(JCParens tree) {
880 tree.expr.accept(this);
881 }
882
883 @Override
884 public void visitTypeCast(JCTypeCast tree) {
885 tree.expr.accept(this);
886 }
887 }
888
889 private ClassReferenceVisitor classReferenceVisitor = new ClassReferenceVisitor();
890
891 /** Visitor method: generate code for an expression, catching and reporting
892 * any completion failures.
893 * @param tree The expression to be visited.
894 * @param pt The expression's expected type (proto-type).
895 */
896 public Item genExpr(JCTree tree, Type pt) {
897 if (!code.isAlive()) {
898 return items.makeStackItem(pt);
899 }
900
901 Type prevPt = this.pt;
902 try {
903 if (tree.type.constValue() != null) {
904 // Short circuit any expressions which are constants
905 tree.accept(classReferenceVisitor);
906 checkStringConstant(tree.pos(), tree.type.constValue());
907 Symbol sym = TreeInfo.symbol(tree);
908 if (sym != null && isConstantDynamic(sym)) {
909 result = items.makeDynamicItem(sym);
910 } else {
911 result = items.makeImmediateItem(tree.type, tree.type.constValue());
912 }
913 } else {
914 this.pt = pt;
915 tree.accept(this);
916 }
917 return result.coerce(pt);
918 } catch (CompletionFailure ex) {
919 chk.completionError(tree.pos(), ex);
920 code.state.stacksize = 1;
921 return items.makeStackItem(pt);
922 } finally {
923 this.pt = prevPt;
924 }
925 }
926
927 public boolean isConstantDynamic(Symbol sym) {
928 return sym.kind == VAR &&
929 sym instanceof DynamicVarSymbol dynamicVarSymbol &&
930 dynamicVarSymbol.isDynamic();
931 }
932
933 /** Derived visitor method: generate code for a list of method arguments.
934 * @param trees The argument expressions to be visited.
935 * @param pts The expression's expected types (i.e. the formal parameter
936 * types of the invoked method).
937 */
938 public void genArgs(List<JCExpression> trees, List<Type> pts) {
939 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail) {
940 genExpr(l.head, pts.head).load();
941 pts = pts.tail;
942 }
943 // require lists be of same length
944 Assert.check(pts.isEmpty());
945 }
946
947 /* ************************************************************************
948 * Visitor methods for statements and definitions
949 *************************************************************************/
950
951 /** Thrown when the byte code size exceeds limit.
952 */
953 public static class CodeSizeOverflow extends RuntimeException {
954 private static final long serialVersionUID = 0;
955 public CodeSizeOverflow() {}
956 }
957
958 public void visitMethodDef(JCMethodDecl tree) {
959 // Create a new local environment that points pack at method
960 // definition.
961 Env<GenContext> localEnv = env.dup(tree);
962 localEnv.enclMethod = tree;
963 // The expected type of every return statement in this method
964 // is the method's return type.
965 this.pt = tree.sym.erasure(types).getReturnType();
966
967 checkDimension(tree.pos(), tree.sym.erasure(types));
968 genMethod(tree, localEnv, false);
969 }
970 //where
971 /** Generate code for a method.
972 * @param tree The tree representing the method definition.
973 * @param env The environment current for the method body.
974 * @param fatcode A flag that indicates whether all jumps are
975 * within 32K. We first invoke this method under
976 * the assumption that fatcode == false, i.e. all
977 * jumps are within 32K. If this fails, fatcode
978 * is set to true and we try again.
979 */
980 void genMethod(JCMethodDecl tree, Env<GenContext> env, boolean fatcode) {
981 MethodSymbol meth = tree.sym;
982 int extras = 0;
983 // Count up extra parameters
984 if (meth.isConstructor()) {
985 extras++;
986 if (meth.enclClass().isInner() &&
987 !meth.enclClass().isStatic()) {
988 extras++;
989 }
990 } else if ((tree.mods.flags & STATIC) == 0) {
991 extras++;
992 }
993 // System.err.println("Generating " + meth + " in " + meth.owner); //DEBUG
994 if (Code.width(types.erasure(env.enclMethod.sym.type).getParameterTypes()) + extras >
995 ClassFile.MAX_PARAMETERS) {
996 log.error(tree.pos(), Errors.LimitParameters);
997 nerrs++;
998 }
999
1000 else if (tree.body != null) {
1001 // Create a new code structure and initialize it.
1002 int startpcCrt = initCode(tree, env, fatcode);
1003 Set<VarSymbol> prevUnsetFields = code.currentUnsetFields;
1004 if (meth.isConstructor()) {
1005 code.currentUnsetFields = unsetFieldsInfo.getUnsetFields(env.enclClass.sym, tree.body);
1006 code.initialUnsetFields = unsetFieldsInfo.getUnsetFields(env.enclClass.sym, tree.body);
1007 }
1008
1009 try {
1010 genStat(tree.body, env);
1011 } catch (CodeSizeOverflow e) {
1012 // Failed due to code limit, try again with jsr/ret
1013 startpcCrt = initCode(tree, env, fatcode);
1014 genStat(tree.body, env);
1015 } finally {
1016 code.currentUnsetFields = prevUnsetFields;
1017 }
1018
1019 if (code.state.stacksize != 0) {
1020 log.error(tree.body.pos(), Errors.StackSimError(tree.sym));
1021 throw new AssertionError();
1022 }
1023
1024 // If last statement could complete normally, insert a
1025 // return at the end.
1026 if (code.isAlive()) {
1027 code.statBegin(TreeInfo.endPos(tree.body));
1028 if (env.enclMethod == null ||
1029 env.enclMethod.sym.type.getReturnType().hasTag(VOID)) {
1030 code.emitop0(return_);
1031 } else {
1032 // sometime dead code seems alive (4415991);
1033 // generate a small loop instead
1034 int startpc = code.entryPoint();
1035 CondItem c = items.makeCondItem(goto_);
1036 code.resolve(c.jumpTrue(), startpc);
1037 }
1038 }
1039 if (genCrt)
1040 code.crt.put(tree.body,
1041 CRT_BLOCK,
1042 startpcCrt,
1043 code.curCP());
1044
1045 code.endScopes(0);
1046
1047 // If we exceeded limits, panic
1048 if (code.checkLimits(tree.pos(), log)) {
1049 nerrs++;
1050 return;
1051 }
1052
1053 // If we generated short code but got a long jump, do it again
1054 // with fatCode = true.
1055 if (!fatcode && code.fatcode) genMethod(tree, env, true);
1056
1057 // Clean up
1058 if(stackMap == StackMapFormat.JSR202) {
1059 code.lastFrame = null;
1060 code.frameBeforeLast = null;
1061 }
1062
1063 // Compress exception table
1064 code.compressCatchTable();
1065
1066 // Fill in type annotation positions for exception parameters
1067 code.fillExceptionParameterPositions();
1068 }
1069 }
1070
1071 private int initCode(JCMethodDecl tree, Env<GenContext> env, boolean fatcode) {
1072 MethodSymbol meth = tree.sym;
1073
1074 // Create a new code structure.
1075 meth.code = code = new Code(meth,
1076 fatcode,
1077 lineDebugInfo ? toplevel.lineMap : null,
1078 varDebugInfo,
1079 stackMap,
1080 debugCode,
1081 genCrt ? new CRTable(tree, env.toplevel.endPositions)
1082 : null,
1083 syms,
1084 types,
1085 poolWriter,
1086 generateEarlyLarvalFrame);
1087 items = new Items(poolWriter, code, syms, types);
1088 if (code.debugCode) {
1089 System.err.println(meth + " for body " + tree);
1090 }
1091
1092 // If method is not static, create a new local variable address
1093 // for `this'.
1094 if ((tree.mods.flags & STATIC) == 0) {
1095 Type selfType = meth.owner.type;
1096 if (meth.isConstructor() && selfType != syms.objectType)
1097 selfType = UninitializedType.uninitializedThis(selfType);
1098 code.setDefined(
1099 code.newLocal(
1100 new VarSymbol(FINAL, names._this, selfType, meth.owner)));
1101 }
1102
1103 // Mark all parameters as defined from the beginning of
1104 // the method.
1105 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
1106 checkDimension(l.head.pos(), l.head.sym.type);
1107 code.setDefined(code.newLocal(l.head.sym));
1108 }
1109
1110 // Get ready to generate code for method body.
1111 int startpcCrt = genCrt ? code.curCP() : 0;
1112 code.entryPoint();
1113
1114 // Suppress initial stackmap
1115 code.pendingStackMap = false;
1116
1117 return startpcCrt;
1118 }
1119
1120 public void visitVarDef(JCVariableDecl tree) {
1121 VarSymbol v = tree.sym;
1122 if (tree.init != null) {
1123 checkStringConstant(tree.init.pos(), v.getConstValue());
1124 if (v.getConstValue() == null || varDebugInfo) {
1125 Assert.check(code.isStatementStart());
1126 code.newLocal(v);
1127 genExpr(tree.init, v.erasure(types)).load();
1128 items.makeLocalItem(v).store();
1129 Assert.check(code.isStatementStart());
1130 }
1131 } else {
1132 code.newLocal(v);
1133 }
1134 checkDimension(tree.pos(), v.type);
1135 }
1136
1137 public void visitSkip(JCSkip tree) {
1138 }
1139
1140 public void visitBlock(JCBlock tree) {
1141 /* this method is heavily invoked, as expected, for deeply nested blocks, if blocks doesn't happen to have
1142 * patterns there will be an unnecessary tax on memory consumption every time this method is executed, for this
1143 * reason we have created helper methods and here at a higher level we just discriminate depending on the
1144 * presence, or not, of patterns in a given block
1145 */
1146 if (tree.patternMatchingCatch != null) {
1147 visitBlockWithPatterns(tree);
1148 } else {
1149 internalVisitBlock(tree);
1150 }
1151 }
1152
1153 private void visitBlockWithPatterns(JCBlock tree) {
1154 PatternMatchingCatchConfiguration prevConfiguration = patternMatchingCatchConfiguration;
1155 try {
1156 patternMatchingCatchConfiguration =
1157 new PatternMatchingCatchConfiguration(tree.patternMatchingCatch.calls2Handle(),
1158 new ListBuffer<int[]>(),
1159 tree.patternMatchingCatch.handler(),
1160 code.state.dup());
1161 internalVisitBlock(tree);
1162 } finally {
1163 generatePatternMatchingCatch(env);
1164 patternMatchingCatchConfiguration = prevConfiguration;
1165 }
1166 }
1167
1168 private void generatePatternMatchingCatch(Env<GenContext> env) {
1169 if (patternMatchingCatchConfiguration.handler != null &&
1170 !patternMatchingCatchConfiguration.ranges.isEmpty()) {
1171 Chain skipCatch = code.branch(goto_);
1172 JCCatch handler = patternMatchingCatchConfiguration.handler();
1173 code.entryPoint(patternMatchingCatchConfiguration.startState(),
1174 handler.param.sym.type);
1175 genPatternMatchingCatch(handler,
1176 env,
1177 patternMatchingCatchConfiguration.ranges.toList());
1178 code.resolve(skipCatch);
1179 }
1180 }
1181
1182 private void internalVisitBlock(JCBlock tree) {
1183 int limit = code.nextreg;
1184 Env<GenContext> localEnv = env.dup(tree, new GenContext());
1185 genStats(tree.stats, localEnv);
1186 // End the scope of all block-local variables in variable info.
1187 if (!env.tree.hasTag(METHODDEF)) {
1188 code.statBegin(tree.endpos);
1189 code.endScopes(limit);
1190 code.pendingStatPos = Position.NOPOS;
1191 }
1192 }
1193
1194 public void visitDoLoop(JCDoWhileLoop tree) {
1195 genLoop(tree, tree.body, tree.cond, List.nil(), false);
1196 }
1197
1198 public void visitWhileLoop(JCWhileLoop tree) {
1199 genLoop(tree, tree.body, tree.cond, List.nil(), true);
1200 }
1201
1202 public void visitForLoop(JCForLoop tree) {
1203 int limit = code.nextreg;
1204 genStats(tree.init, env);
1205 genLoop(tree, tree.body, tree.cond, tree.step, true);
1206 code.endScopes(limit);
1207 }
1208 //where
1209 /** Generate code for a loop.
1210 * @param loop The tree representing the loop.
1211 * @param body The loop's body.
1212 * @param cond The loop's controlling condition.
1213 * @param step "Step" statements to be inserted at end of
1214 * each iteration.
1215 * @param testFirst True if the loop test belongs before the body.
1216 */
1217 private void genLoop(JCStatement loop,
1218 JCStatement body,
1219 JCExpression cond,
1220 List<JCExpressionStatement> step,
1221 boolean testFirst) {
1222 Set<VarSymbol> prevCodeUnsetFields = code.currentUnsetFields;
1223 try {
1224 genLoopHelper(loop, body, cond, step, testFirst);
1225 } finally {
1226 code.currentUnsetFields = prevCodeUnsetFields;
1227 }
1228 }
1229
1230 private void genLoopHelper(JCStatement loop,
1231 JCStatement body,
1232 JCExpression cond,
1233 List<JCExpressionStatement> step,
1234 boolean testFirst) {
1235 Env<GenContext> loopEnv = env.dup(loop, new GenContext());
1236 int startpc = code.entryPoint();
1237 if (testFirst) { //while or for loop
1238 CondItem c;
1239 if (cond != null) {
1240 code.statBegin(cond.pos);
1241 Assert.check(code.isStatementStart());
1242 c = genCond(TreeInfo.skipParens(cond), CRT_FLOW_CONTROLLER);
1243 } else {
1244 c = items.makeCondItem(goto_);
1245 }
1246 Chain loopDone = c.jumpFalse();
1247 code.resolve(c.trueJumps);
1248 Assert.check(code.isStatementStart());
1249 genStat(body, loopEnv, CRT_STATEMENT | CRT_FLOW_TARGET);
1250 code.resolve(loopEnv.info.cont);
1251 genStats(step, loopEnv);
1252 code.resolve(code.branch(goto_), startpc);
1253 code.resolve(loopDone);
1254 } else {
1255 genStat(body, loopEnv, CRT_STATEMENT | CRT_FLOW_TARGET);
1256 code.resolve(loopEnv.info.cont);
1257 genStats(step, loopEnv);
1258 if (code.isAlive()) {
1259 CondItem c;
1260 if (cond != null) {
1261 code.statBegin(cond.pos);
1262 Assert.check(code.isStatementStart());
1263 c = genCond(TreeInfo.skipParens(cond), CRT_FLOW_CONTROLLER);
1264 } else {
1265 c = items.makeCondItem(goto_);
1266 }
1267 code.resolve(c.jumpTrue(), startpc);
1268 Assert.check(code.isStatementStart());
1269 code.resolve(c.falseJumps);
1270 }
1271 }
1272 code.resolve(loopEnv.info.exit);
1273 }
1274
1275 public void visitForeachLoop(JCEnhancedForLoop tree) {
1276 throw new AssertionError(); // should have been removed by Lower.
1277 }
1278
1279 public void visitLabelled(JCLabeledStatement tree) {
1280 Env<GenContext> localEnv = env.dup(tree, new GenContext());
1281 genStat(tree.body, localEnv, CRT_STATEMENT);
1282 code.resolve(localEnv.info.exit);
1283 }
1284
1285 public void visitSwitch(JCSwitch tree) {
1286 handleSwitch(tree, tree.selector, tree.cases, tree.patternSwitch);
1287 }
1288
1289 @Override
1290 public void visitSwitchExpression(JCSwitchExpression tree) {
1291 code.resolvePending();
1292 boolean prevInCondSwitchExpression = inCondSwitchExpression;
1293 Set<VarSymbol> prevCodeUnsetFields = code.currentUnsetFields;
1294 try {
1295 inCondSwitchExpression = false;
1296 doHandleSwitchExpression(tree);
1297 } finally {
1298 inCondSwitchExpression = prevInCondSwitchExpression;
1299 code.currentUnsetFields = prevCodeUnsetFields;
1300 }
1301 result = items.makeStackItem(pt);
1302 }
1303
1304 private void doHandleSwitchExpression(JCSwitchExpression tree) {
1305 List<LocalItem> prevStackBeforeSwitchExpression = stackBeforeSwitchExpression;
1306 LocalItem prevSwitchResult = switchResult;
1307 int limit = code.nextreg;
1308 try {
1309 stackBeforeSwitchExpression = List.nil();
1310 switchResult = null;
1311 if (hasTry(tree)) {
1312 //if the switch expression contains try-catch, the catch handlers need to have
1313 //an empty stack. So stash whole stack to local variables, and restore it before
1314 //breaks:
1315 while (code.state.stacksize > 0) {
1316 Type type = code.state.peek();
1317 Name varName = names.fromString(target.syntheticNameChar() +
1318 "stack" +
1319 target.syntheticNameChar() +
1320 tree.pos +
1321 target.syntheticNameChar() +
1322 code.state.stacksize);
1323 VarSymbol var = new VarSymbol(Flags.SYNTHETIC, varName, type,
1324 this.env.enclMethod.sym);
1325 LocalItem item = items.new LocalItem(type, code.newLocal(var));
1326 stackBeforeSwitchExpression = stackBeforeSwitchExpression.prepend(item);
1327 item.store();
1328 }
1329 switchResult = makeTemp(tree.type);
1330 }
1331 int prevLetExprStart = code.setLetExprStackPos(code.state.stacksize);
1332 try {
1333 handleSwitch(tree, tree.selector, tree.cases, tree.patternSwitch);
1334 } finally {
1335 code.setLetExprStackPos(prevLetExprStart);
1336 }
1337 } finally {
1338 stackBeforeSwitchExpression = prevStackBeforeSwitchExpression;
1339 switchResult = prevSwitchResult;
1340 code.endScopes(limit);
1341 }
1342 }
1343 //where:
1344 private boolean hasTry(JCSwitchExpression tree) {
1345 class HasTryScanner extends TreeScanner {
1346 private boolean hasTry;
1347
1348 @Override
1349 public void visitTry(JCTry tree) {
1350 hasTry = true;
1351 }
1352
1353 @Override
1354 public void visitSynchronized(JCSynchronized tree) {
1355 hasTry = true;
1356 }
1357
1358 @Override
1359 public void visitClassDef(JCClassDecl tree) {
1360 }
1361
1362 @Override
1363 public void visitLambda(JCLambda tree) {
1364 }
1365 };
1366
1367 HasTryScanner hasTryScanner = new HasTryScanner();
1368
1369 hasTryScanner.scan(tree);
1370 return hasTryScanner.hasTry;
1371 }
1372
1373 private void handleSwitch(JCTree swtch, JCExpression selector, List<JCCase> cases,
1374 boolean patternSwitch) {
1375 Set<VarSymbol> prevCodeUnsetFields = code.currentUnsetFields;
1376 try {
1377 handleSwitchHelper(swtch, selector, cases, patternSwitch);
1378 } finally {
1379 code.currentUnsetFields = prevCodeUnsetFields;
1380 }
1381 }
1382
1383 void handleSwitchHelper(JCTree swtch, JCExpression selector, List<JCCase> cases,
1384 boolean patternSwitch) {
1385 int limit = code.nextreg;
1386 Assert.check(!selector.type.hasTag(CLASS));
1387 int switchStart = patternSwitch ? code.entryPoint() : -1;
1388 int startpcCrt = genCrt ? code.curCP() : 0;
1389 Assert.check(code.isStatementStart());
1390 Item sel = genExpr(selector, syms.intType);
1391 if (cases.isEmpty()) {
1392 // We are seeing: switch <sel> {}
1393 sel.load().drop();
1394 if (genCrt)
1395 code.crt.put(TreeInfo.skipParens(selector),
1396 CRT_FLOW_CONTROLLER, startpcCrt, code.curCP());
1397 } else {
1398 // We are seeing a nonempty switch.
1399 sel.load();
1400 if (genCrt)
1401 code.crt.put(TreeInfo.skipParens(selector),
1402 CRT_FLOW_CONTROLLER, startpcCrt, code.curCP());
1403 Env<GenContext> switchEnv = env.dup(swtch, new GenContext());
1404 switchEnv.info.isSwitch = true;
1405
1406 // Compute number of labels and minimum and maximum label values.
1407 // For each case, store its label in an array.
1408 int lo = Integer.MAX_VALUE; // minimum label.
1409 int hi = Integer.MIN_VALUE; // maximum label.
1410 int nlabels = 0; // number of labels.
1411
1412 int[] labels = new int[cases.length()]; // the label array.
1413 int defaultIndex = -1; // the index of the default clause.
1414
1415 List<JCCase> l = cases;
1416 for (int i = 0; i < labels.length; i++) {
1417 if (l.head.labels.head instanceof JCConstantCaseLabel constLabel) {
1418 Assert.check(l.head.labels.size() == 1);
1419 int val = ((Number) constLabel.expr.type.constValue()).intValue();
1420 labels[i] = val;
1421 if (val < lo) lo = val;
1422 if (hi < val) hi = val;
1423 nlabels++;
1424 } else {
1425 Assert.check(defaultIndex == -1);
1426 defaultIndex = i;
1427 }
1428 l = l.tail;
1429 }
1430
1431 // Determine whether to issue a tableswitch or a lookupswitch
1432 // instruction.
1433 long table_space_cost = 4 + ((long) hi - lo + 1); // words
1434 long table_time_cost = 3; // comparisons
1435 long lookup_space_cost = 3 + 2 * (long) nlabels;
1436 long lookup_time_cost = nlabels;
1437 int opcode =
1438 nlabels > 0 &&
1439 table_space_cost + 3 * table_time_cost <=
1440 lookup_space_cost + 3 * lookup_time_cost
1441 ?
1442 tableswitch : lookupswitch;
1443
1444 int startpc = code.curCP(); // the position of the selector operation
1445 code.emitop0(opcode);
1446 code.align(4);
1447 int tableBase = code.curCP(); // the start of the jump table
1448 int[] offsets = null; // a table of offsets for a lookupswitch
1449 code.emit4(-1); // leave space for default offset
1450 if (opcode == tableswitch) {
1451 code.emit4(lo); // minimum label
1452 code.emit4(hi); // maximum label
1453 for (long i = lo; i <= hi; i++) { // leave space for jump table
1454 code.emit4(-1);
1455 }
1456 } else {
1457 code.emit4(nlabels); // number of labels
1458 for (int i = 0; i < nlabels; i++) {
1459 code.emit4(-1); code.emit4(-1); // leave space for lookup table
1460 }
1461 offsets = new int[labels.length];
1462 }
1463 Code.State stateSwitch = code.state.dup();
1464 code.markDead();
1465
1466 // For each case do:
1467 l = cases;
1468 for (int i = 0; i < labels.length; i++) {
1469 JCCase c = l.head;
1470 l = l.tail;
1471
1472 int pc = code.entryPoint(stateSwitch);
1473 // Insert offset directly into code or else into the
1474 // offsets table.
1475 if (i != defaultIndex) {
1476 if (opcode == tableswitch) {
1477 code.put4(
1478 tableBase + 4 * (labels[i] - lo + 3),
1479 pc - startpc);
1480 } else {
1481 offsets[i] = pc - startpc;
1482 }
1483 } else {
1484 code.put4(tableBase, pc - startpc);
1485 }
1486
1487 // Generate code for the statements in this case.
1488 genStats(c.stats, switchEnv, CRT_FLOW_TARGET);
1489 }
1490
1491 if (switchEnv.info.cont != null) {
1492 Assert.check(patternSwitch);
1493 code.resolve(switchEnv.info.cont, switchStart);
1494 }
1495
1496 // Resolve all breaks.
1497 code.resolve(switchEnv.info.exit);
1498
1499 // If we have not set the default offset, we do so now.
1500 if (code.get4(tableBase) == -1) {
1501 code.put4(tableBase, code.entryPoint(stateSwitch) - startpc);
1502 }
1503
1504 if (opcode == tableswitch) {
1505 // Let any unfilled slots point to the default case.
1506 int defaultOffset = code.get4(tableBase);
1507 for (long i = lo; i <= hi; i++) {
1508 int t = (int)(tableBase + 4 * (i - lo + 3));
1509 if (code.get4(t) == -1)
1510 code.put4(t, defaultOffset);
1511 }
1512 } else {
1513 // Sort non-default offsets and copy into lookup table.
1514 if (defaultIndex >= 0)
1515 for (int i = defaultIndex; i < labels.length - 1; i++) {
1516 labels[i] = labels[i+1];
1517 offsets[i] = offsets[i+1];
1518 }
1519 if (nlabels > 0)
1520 qsort2(labels, offsets, 0, nlabels - 1);
1521 for (int i = 0; i < nlabels; i++) {
1522 int caseidx = tableBase + 8 * (i + 1);
1523 code.put4(caseidx, labels[i]);
1524 code.put4(caseidx + 4, offsets[i]);
1525 }
1526 }
1527
1528 if (swtch instanceof JCSwitchExpression) {
1529 // Emit line position for the end of a switch expression
1530 code.statBegin(TreeInfo.endPos(swtch));
1531 }
1532 }
1533 code.endScopes(limit);
1534 }
1535 //where
1536 /** Sort (int) arrays of keys and values
1537 */
1538 static void qsort2(int[] keys, int[] values, int lo, int hi) {
1539 int i = lo;
1540 int j = hi;
1541 int pivot = keys[(i+j)/2];
1542 do {
1543 while (keys[i] < pivot) i++;
1544 while (pivot < keys[j]) j--;
1545 if (i <= j) {
1546 int temp1 = keys[i];
1547 keys[i] = keys[j];
1548 keys[j] = temp1;
1549 int temp2 = values[i];
1550 values[i] = values[j];
1551 values[j] = temp2;
1552 i++;
1553 j--;
1554 }
1555 } while (i <= j);
1556 if (lo < j) qsort2(keys, values, lo, j);
1557 if (i < hi) qsort2(keys, values, i, hi);
1558 }
1559
1560 public void visitSynchronized(JCSynchronized tree) {
1561 int limit = code.nextreg;
1562 // Generate code to evaluate lock and save in temporary variable.
1563 final LocalItem lockVar = makeTemp(syms.objectType);
1564 Assert.check(code.isStatementStart());
1565 genExpr(tree.lock, tree.lock.type).load().duplicate();
1566 lockVar.store();
1567
1568 // Generate code to enter monitor.
1569 code.emitop0(monitorenter);
1570 code.state.lock(lockVar.reg);
1571
1572 // Generate code for a try statement with given body, no catch clauses
1573 // in a new environment with the "exit-monitor" operation as finalizer.
1574 final Env<GenContext> syncEnv = env.dup(tree, new GenContext());
1575 syncEnv.info.finalize = new GenFinalizer() {
1576 void gen() {
1577 genLast();
1578 Assert.check(syncEnv.info.gaps.length() % 2 == 0);
1579 syncEnv.info.gaps.append(code.curCP());
1580 }
1581 void genLast() {
1582 if (code.isAlive()) {
1583 lockVar.load();
1584 code.emitop0(monitorexit);
1585 code.state.unlock(lockVar.reg);
1586 }
1587 }
1588 };
1589 syncEnv.info.gaps = new ListBuffer<>();
1590 genTry(tree.body, List.nil(), syncEnv);
1591 code.endScopes(limit);
1592 }
1593
1594 public void visitTry(final JCTry tree) {
1595 // Generate code for a try statement with given body and catch clauses,
1596 // in a new environment which calls the finally block if there is one.
1597 final Env<GenContext> tryEnv = env.dup(tree, new GenContext());
1598 final Env<GenContext> oldEnv = env;
1599 tryEnv.info.finalize = new GenFinalizer() {
1600 void gen() {
1601 Assert.check(tryEnv.info.gaps.length() % 2 == 0);
1602 tryEnv.info.gaps.append(code.curCP());
1603 genLast();
1604 }
1605 void genLast() {
1606 if (tree.finalizer != null)
1607 genStat(tree.finalizer, oldEnv, CRT_BLOCK);
1608 }
1609 boolean hasFinalizer() {
1610 return tree.finalizer != null;
1611 }
1612
1613 @Override
1614 void afterBody() {
1615 if (tree.finalizer != null && (tree.finalizer.flags & BODY_ONLY_FINALIZE) != 0) {
1616 //for body-only finally, remove the GenFinalizer after try body
1617 //so that the finally is not generated to catch bodies:
1618 tryEnv.info.finalize = null;
1619 }
1620 }
1621
1622 };
1623 tryEnv.info.gaps = new ListBuffer<>();
1624 genTry(tree.body, tree.catchers, tryEnv);
1625 }
1626 //where
1627 /** Generate code for a try or synchronized statement
1628 * @param body The body of the try or synchronized statement.
1629 * @param catchers The list of catch clauses.
1630 * @param env The current environment of the body.
1631 */
1632 void genTry(JCTree body, List<JCCatch> catchers, Env<GenContext> env) {
1633 Set<VarSymbol> prevCodeUnsetFields = code.currentUnsetFields;
1634 try {
1635 genTryHelper(body, catchers, env);
1636 } finally {
1637 code.currentUnsetFields = prevCodeUnsetFields;
1638 }
1639 }
1640
1641 void genTryHelper(JCTree body, List<JCCatch> catchers, Env<GenContext> env) {
1642 int limit = code.nextreg;
1643 int startpc = code.curCP();
1644 Code.State stateTry = code.state.dup();
1645 genStat(body, env, CRT_BLOCK);
1646 int endpc = code.curCP();
1647 List<Integer> gaps = env.info.gaps.toList();
1648 code.statBegin(TreeInfo.endPos(body));
1649 genFinalizer(env);
1650 code.statBegin(TreeInfo.endPos(env.tree));
1651 Chain exitChain;
1652 boolean actualTry = env.tree.hasTag(TRY);
1653 if (startpc == endpc && actualTry) {
1654 exitChain = code.branch(dontgoto);
1655 } else {
1656 exitChain = code.branch(goto_);
1657 }
1658 endFinalizerGap(env);
1659 env.info.finalize.afterBody();
1660 boolean hasFinalizer =
1661 env.info.finalize != null &&
1662 env.info.finalize.hasFinalizer();
1663 if (startpc != endpc) for (List<JCCatch> l = catchers; l.nonEmpty(); l = l.tail) {
1664 // start off with exception on stack
1665 code.entryPoint(stateTry, l.head.param.sym.type);
1666 genCatch(l.head, env, startpc, endpc, gaps);
1667 genFinalizer(env);
1668 if (hasFinalizer || l.tail.nonEmpty()) {
1669 code.statBegin(TreeInfo.endPos(env.tree));
1670 exitChain = Code.mergeChains(exitChain,
1671 code.branch(goto_));
1672 }
1673 endFinalizerGap(env);
1674 }
1675 if (hasFinalizer && (startpc != endpc || !actualTry)) {
1676 // Create a new register segment to avoid allocating
1677 // the same variables in finalizers and other statements.
1678 code.newRegSegment();
1679
1680 // Add a catch-all clause.
1681
1682 // start off with exception on stack
1683 int catchallpc = code.entryPoint(stateTry, syms.throwableType);
1684
1685 // Register all exception ranges for catch all clause.
1686 // The range of the catch all clause is from the beginning
1687 // of the try or synchronized block until the present
1688 // code pointer excluding all gaps in the current
1689 // environment's GenContext.
1690 int startseg = startpc;
1691 while (env.info.gaps.nonEmpty()) {
1692 int endseg = env.info.gaps.next().intValue();
1693 registerCatch(body.pos(), startseg, endseg,
1694 catchallpc, 0);
1695 startseg = env.info.gaps.next().intValue();
1696 }
1697 code.statBegin(TreeInfo.finalizerPos(env.tree, PosKind.FIRST_STAT_POS));
1698 code.markStatBegin();
1699
1700 Item excVar = makeTemp(syms.throwableType);
1701 excVar.store();
1702 genFinalizer(env);
1703 code.resolvePending();
1704 code.statBegin(TreeInfo.finalizerPos(env.tree, PosKind.END_POS));
1705 code.markStatBegin();
1706
1707 excVar.load();
1708 registerCatch(body.pos(), startseg,
1709 env.info.gaps.next().intValue(),
1710 catchallpc, 0);
1711 code.emitop0(athrow);
1712 code.markDead();
1713
1714 // If there are jsr's to this finalizer, ...
1715 if (env.info.cont != null) {
1716 // Resolve all jsr's.
1717 code.resolve(env.info.cont);
1718
1719 // Mark statement line number
1720 code.statBegin(TreeInfo.finalizerPos(env.tree, PosKind.FIRST_STAT_POS));
1721 code.markStatBegin();
1722
1723 // Save return address.
1724 LocalItem retVar = makeTemp(syms.throwableType);
1725 retVar.store();
1726
1727 // Generate finalizer code.
1728 env.info.finalize.genLast();
1729
1730 // Return.
1731 code.emitop1w(ret, retVar.reg);
1732 code.markDead();
1733 }
1734 }
1735 // Resolve all breaks.
1736 code.resolve(exitChain);
1737
1738 code.endScopes(limit);
1739 }
1740
1741 /** Generate code for a catch clause.
1742 * @param tree The catch clause.
1743 * @param env The environment current in the enclosing try.
1744 * @param startpc Start pc of try-block.
1745 * @param endpc End pc of try-block.
1746 */
1747 void genCatch(JCCatch tree,
1748 Env<GenContext> env,
1749 int startpc, int endpc,
1750 List<Integer> gaps) {
1751 if (startpc != endpc) {
1752 List<Pair<List<Attribute.TypeCompound>, JCExpression>> catchTypeExprs
1753 = catchTypesWithAnnotations(tree);
1754 while (gaps.nonEmpty()) {
1755 for (Pair<List<Attribute.TypeCompound>, JCExpression> subCatch1 : catchTypeExprs) {
1756 JCExpression subCatch = subCatch1.snd;
1757 int catchType = makeRef(tree.pos(), subCatch.type);
1758 int end = gaps.head.intValue();
1759 registerCatch(tree.pos(),
1760 startpc, end, code.curCP(),
1761 catchType);
1762 for (Attribute.TypeCompound tc : subCatch1.fst) {
1763 tc.position.setCatchInfo(catchType, startpc);
1764 }
1765 }
1766 gaps = gaps.tail;
1767 startpc = gaps.head.intValue();
1768 gaps = gaps.tail;
1769 }
1770 if (startpc < endpc) {
1771 for (Pair<List<Attribute.TypeCompound>, JCExpression> subCatch1 : catchTypeExprs) {
1772 JCExpression subCatch = subCatch1.snd;
1773 int catchType = makeRef(tree.pos(), subCatch.type);
1774 registerCatch(tree.pos(),
1775 startpc, endpc, code.curCP(),
1776 catchType);
1777 for (Attribute.TypeCompound tc : subCatch1.fst) {
1778 tc.position.setCatchInfo(catchType, startpc);
1779 }
1780 }
1781 }
1782 genCatchBlock(tree, env);
1783 }
1784 }
1785 void genPatternMatchingCatch(JCCatch tree,
1786 Env<GenContext> env,
1787 List<int[]> ranges) {
1788 for (int[] range : ranges) {
1789 JCExpression subCatch = tree.param.vartype;
1790 int catchType = makeRef(tree.pos(), subCatch.type);
1791 registerCatch(tree.pos(),
1792 range[0], range[1], code.curCP(),
1793 catchType);
1794 }
1795 genCatchBlock(tree, env);
1796 }
1797 void genCatchBlock(JCCatch tree, Env<GenContext> env) {
1798 VarSymbol exparam = tree.param.sym;
1799 code.statBegin(tree.pos);
1800 code.markStatBegin();
1801 int limit = code.nextreg;
1802 code.newLocal(exparam);
1803 items.makeLocalItem(exparam).store();
1804 code.statBegin(TreeInfo.firstStatPos(tree.body));
1805 genStat(tree.body, env, CRT_BLOCK);
1806 code.endScopes(limit);
1807 code.statBegin(TreeInfo.endPos(tree.body));
1808 }
1809 // where
1810 List<Pair<List<Attribute.TypeCompound>, JCExpression>> catchTypesWithAnnotations(JCCatch tree) {
1811 return TreeInfo.isMultiCatch(tree) ?
1812 catchTypesWithAnnotationsFromMulticatch((JCTypeUnion)tree.param.vartype, tree.param.sym.getRawTypeAttributes()) :
1813 List.of(new Pair<>(tree.param.sym.getRawTypeAttributes(), tree.param.vartype));
1814 }
1815 // where
1816 List<Pair<List<Attribute.TypeCompound>, JCExpression>> catchTypesWithAnnotationsFromMulticatch(JCTypeUnion tree, List<TypeCompound> first) {
1817 List<JCExpression> alts = tree.alternatives;
1818 List<Pair<List<TypeCompound>, JCExpression>> res = List.of(new Pair<>(first, alts.head));
1819 alts = alts.tail;
1820
1821 while(alts != null && alts.head != null) {
1822 JCExpression alt = alts.head;
1823 if (alt instanceof JCAnnotatedType annotatedType) {
1824 res = res.prepend(new Pair<>(annotate.fromAnnotations(annotatedType.annotations), alt));
1825 } else {
1826 res = res.prepend(new Pair<>(List.nil(), alt));
1827 }
1828 alts = alts.tail;
1829 }
1830 return res.reverse();
1831 }
1832
1833 /** Register a catch clause in the "Exceptions" code-attribute.
1834 */
1835 void registerCatch(DiagnosticPosition pos,
1836 int startpc, int endpc,
1837 int handler_pc, int catch_type) {
1838 char startpc1 = (char)startpc;
1839 char endpc1 = (char)endpc;
1840 char handler_pc1 = (char)handler_pc;
1841 if (startpc1 == startpc &&
1842 endpc1 == endpc &&
1843 handler_pc1 == handler_pc) {
1844 code.addCatch(startpc1, endpc1, handler_pc1,
1845 (char)catch_type);
1846 } else {
1847 log.error(pos, Errors.LimitCodeTooLargeForTryStmt);
1848 nerrs++;
1849 }
1850 }
1851
1852 public void visitIf(JCIf tree) {
1853 Set<VarSymbol> prevCodeUnsetFields = code.currentUnsetFields;
1854 try {
1855 visitIfHelper(tree);
1856 } finally {
1857 code.currentUnsetFields = prevCodeUnsetFields;
1858 }
1859 }
1860
1861 public void visitIfHelper(JCIf tree) {
1862 int limit = code.nextreg;
1863 Chain thenExit = null;
1864 Assert.check(code.isStatementStart());
1865 CondItem c = genCond(TreeInfo.skipParens(tree.cond),
1866 CRT_FLOW_CONTROLLER);
1867 Chain elseChain = c.jumpFalse();
1868 Assert.check(code.isStatementStart());
1869 if (!c.isFalse()) {
1870 code.resolve(c.trueJumps);
1871 genStat(tree.thenpart, env, CRT_STATEMENT | CRT_FLOW_TARGET);
1872 thenExit = code.branch(goto_);
1873 }
1874 if (elseChain != null) {
1875 code.resolve(elseChain);
1876 if (tree.elsepart != null) {
1877 genStat(tree.elsepart, env,CRT_STATEMENT | CRT_FLOW_TARGET);
1878 }
1879 }
1880 code.resolve(thenExit);
1881 code.endScopes(limit);
1882 Assert.check(code.isStatementStart());
1883 }
1884
1885 public void visitExec(JCExpressionStatement tree) {
1886 // Optimize x++ to ++x and x-- to --x.
1887 JCExpression e = tree.expr;
1888 switch (e.getTag()) {
1889 case POSTINC:
1890 ((JCUnary) e).setTag(PREINC);
1891 break;
1892 case POSTDEC:
1893 ((JCUnary) e).setTag(PREDEC);
1894 break;
1895 }
1896 Assert.check(code.isStatementStart());
1897 genExpr(tree.expr, tree.expr.type).drop();
1898 Assert.check(code.isStatementStart());
1899 }
1900
1901 public void visitBreak(JCBreak tree) {
1902 Assert.check(code.isStatementStart());
1903 final Env<GenContext> targetEnv = unwindBreak(tree.target);
1904 targetEnv.info.addExit(code.branch(goto_));
1905 endFinalizerGaps(env, targetEnv);
1906 }
1907
1908 public void visitYield(JCYield tree) {
1909 Assert.check(code.isStatementStart());
1910 final Env<GenContext> targetEnv;
1911 if (inCondSwitchExpression) {
1912 CondItem value = genCond(tree.value, CRT_FLOW_TARGET);
1913 Chain falseJumps = value.jumpFalse();
1914
1915 code.resolve(value.trueJumps);
1916 Env<GenContext> localEnv = unwindBreak(tree.target);
1917 reloadStackBeforeSwitchExpr();
1918 Chain trueJumps = code.branch(goto_);
1919
1920 endFinalizerGaps(env, localEnv);
1921
1922 code.resolve(falseJumps);
1923 targetEnv = unwindBreak(tree.target);
1924 reloadStackBeforeSwitchExpr();
1925 falseJumps = code.branch(goto_);
1926
1927 if (switchExpressionTrueChain == null) {
1928 switchExpressionTrueChain = trueJumps;
1929 } else {
1930 switchExpressionTrueChain =
1931 Code.mergeChains(switchExpressionTrueChain, trueJumps);
1932 }
1933 if (switchExpressionFalseChain == null) {
1934 switchExpressionFalseChain = falseJumps;
1935 } else {
1936 switchExpressionFalseChain =
1937 Code.mergeChains(switchExpressionFalseChain, falseJumps);
1938 }
1939 } else {
1940 genExpr(tree.value, pt).load();
1941 if (switchResult != null)
1942 switchResult.store();
1943
1944 targetEnv = unwindBreak(tree.target);
1945
1946 if (code.isAlive()) {
1947 reloadStackBeforeSwitchExpr();
1948 if (switchResult != null)
1949 switchResult.load();
1950
1951 targetEnv.info.addExit(code.branch(goto_));
1952 code.markDead();
1953 }
1954 }
1955 endFinalizerGaps(env, targetEnv);
1956 }
1957 //where:
1958 /** As side-effect, might mark code as dead disabling any further emission.
1959 */
1960 private Env<GenContext> unwindBreak(JCTree target) {
1961 int tmpPos = code.pendingStatPos;
1962 Env<GenContext> targetEnv = unwind(target, env);
1963 code.pendingStatPos = tmpPos;
1964 return targetEnv;
1965 }
1966
1967 private void reloadStackBeforeSwitchExpr() {
1968 for (LocalItem li : stackBeforeSwitchExpression)
1969 li.load();
1970 }
1971
1972 public void visitContinue(JCContinue tree) {
1973 int tmpPos = code.pendingStatPos;
1974 Env<GenContext> targetEnv = unwind(tree.target, env);
1975 code.pendingStatPos = tmpPos;
1976 Assert.check(code.isStatementStart());
1977 targetEnv.info.addCont(code.branch(goto_));
1978 endFinalizerGaps(env, targetEnv);
1979 }
1980
1981 public void visitReturn(JCReturn tree) {
1982 int limit = code.nextreg;
1983 final Env<GenContext> targetEnv;
1984
1985 /* Save and then restore the location of the return in case a finally
1986 * is expanded (with unwind()) in the middle of our bytecodes.
1987 */
1988 int tmpPos = code.pendingStatPos;
1989 if (tree.expr != null) {
1990 Assert.check(code.isStatementStart());
1991 Item r = genExpr(tree.expr, pt).load();
1992 if (hasFinally(env.enclMethod, env)) {
1993 r = makeTemp(pt);
1994 r.store();
1995 }
1996 targetEnv = unwind(env.enclMethod, env);
1997 code.pendingStatPos = tmpPos;
1998 r.load();
1999 code.emitop0(ireturn + Code.truncate(Code.typecode(pt)));
2000 } else {
2001 targetEnv = unwind(env.enclMethod, env);
2002 code.pendingStatPos = tmpPos;
2003 code.emitop0(return_);
2004 }
2005 endFinalizerGaps(env, targetEnv);
2006 code.endScopes(limit);
2007 }
2008
2009 public void visitThrow(JCThrow tree) {
2010 Assert.check(code.isStatementStart());
2011 genExpr(tree.expr, tree.expr.type).load();
2012 code.emitop0(athrow);
2013 Assert.check(code.isStatementStart());
2014 }
2015
2016 /* ************************************************************************
2017 * Visitor methods for expressions
2018 *************************************************************************/
2019
2020 public void visitApply(JCMethodInvocation tree) {
2021 setTypeAnnotationPositions(tree.pos);
2022 // Generate code for method.
2023 Item m = genExpr(tree.meth, methodType);
2024 // Generate code for all arguments, where the expected types are
2025 // the parameters of the method's external type (that is, any implicit
2026 // outer instance of a super(...) call appears as first parameter).
2027 MethodSymbol msym = (MethodSymbol)TreeInfo.symbol(tree.meth);
2028 genArgs(tree.args,
2029 msym.externalType(types).getParameterTypes());
2030 if (!msym.isDynamic()) {
2031 code.statBegin(tree.pos);
2032 }
2033 if (patternMatchingCatchConfiguration.invocations().contains(tree)) {
2034 int start = code.curCP();
2035 result = m.invoke();
2036 patternMatchingCatchConfiguration.ranges().add(new int[] {start, code.curCP()});
2037 } else {
2038 if (msym.isConstructor() && TreeInfo.isConstructorCall(tree)) {
2039 //if this is a this(...) or super(...) call, there is a pending
2040 //"uninitialized this" before this call. One catch handler cannot
2041 //handle exceptions that may come from places with "uninitialized this"
2042 //and (initialized) this, hence generate one set of handlers here
2043 //for the "uninitialized this" case, and another set of handlers
2044 //will be generated at the end of the method for the initialized this,
2045 //if needed:
2046 generatePatternMatchingCatch(env);
2047 result = m.invoke();
2048 patternMatchingCatchConfiguration =
2049 patternMatchingCatchConfiguration.restart(code.state.dup());
2050 } else {
2051 result = m.invoke();
2052 }
2053 }
2054 }
2055
2056 public void visitConditional(JCConditional tree) {
2057 Chain thenExit = null;
2058 code.statBegin(tree.cond.pos);
2059 CondItem c = genCond(tree.cond, CRT_FLOW_CONTROLLER);
2060 Chain elseChain = c.jumpFalse();
2061 if (!c.isFalse()) {
2062 code.resolve(c.trueJumps);
2063 int startpc = genCrt ? code.curCP() : 0;
2064 code.statBegin(tree.truepart.pos);
2065 genExpr(tree.truepart, pt).load();
2066 if (genCrt) code.crt.put(tree.truepart, CRT_FLOW_TARGET,
2067 startpc, code.curCP());
2068 thenExit = code.branch(goto_);
2069 }
2070 if (elseChain != null) {
2071 code.resolve(elseChain);
2072 int startpc = genCrt ? code.curCP() : 0;
2073 code.statBegin(tree.falsepart.pos);
2074 genExpr(tree.falsepart, pt).load();
2075 if (genCrt) code.crt.put(tree.falsepart, CRT_FLOW_TARGET,
2076 startpc, code.curCP());
2077 }
2078 code.resolve(thenExit);
2079 result = items.makeStackItem(pt);
2080 }
2081
2082 private void setTypeAnnotationPositions(int treePos) {
2083 MethodSymbol meth = code.meth;
2084 boolean initOrClinit = code.meth.getKind() == javax.lang.model.element.ElementKind.CONSTRUCTOR
2085 || code.meth.getKind() == javax.lang.model.element.ElementKind.STATIC_INIT;
2086
2087 for (Attribute.TypeCompound ta : meth.getRawTypeAttributes()) {
2088 if (ta.hasUnknownPosition())
2089 ta.tryFixPosition();
2090
2091 if (ta.position.matchesPos(treePos))
2092 ta.position.updatePosOffset(code.cp);
2093 }
2094
2095 if (!initOrClinit)
2096 return;
2097
2098 for (Attribute.TypeCompound ta : meth.owner.getRawTypeAttributes()) {
2099 if (ta.hasUnknownPosition())
2100 ta.tryFixPosition();
2101
2102 if (ta.position.matchesPos(treePos))
2103 ta.position.updatePosOffset(code.cp);
2104 }
2105
2106 ClassSymbol clazz = meth.enclClass();
2107 for (Symbol s : new com.sun.tools.javac.model.FilteredMemberList(clazz.members())) {
2108 if (!s.getKind().isField())
2109 continue;
2110
2111 for (Attribute.TypeCompound ta : s.getRawTypeAttributes()) {
2112 if (ta.hasUnknownPosition())
2113 ta.tryFixPosition();
2114
2115 if (ta.position.matchesPos(treePos))
2116 ta.position.updatePosOffset(code.cp);
2117 }
2118 }
2119 }
2120
2121 public void visitNewClass(JCNewClass tree) {
2122 // Enclosing instances or anonymous classes should have been eliminated
2123 // by now.
2124 Assert.check(tree.encl == null && tree.def == null);
2125 setTypeAnnotationPositions(tree.pos);
2126
2127 code.emitop2(new_, checkDimension(tree.pos(), tree.type), PoolWriter::putClass);
2128 code.emitop0(dup);
2129
2130 // Generate code for all arguments, where the expected types are
2131 // the parameters of the constructor's external type (that is,
2132 // any implicit outer instance appears as first parameter).
2133 genArgs(tree.args, tree.constructor.externalType(types).getParameterTypes());
2134
2135 items.makeMemberItem(tree.constructor, true).invoke();
2136 result = items.makeStackItem(tree.type);
2137 }
2138
2139 public void visitNewArray(JCNewArray tree) {
2140 setTypeAnnotationPositions(tree.pos);
2141
2142 if (tree.elems != null) {
2143 Type elemtype = types.elemtype(tree.type);
2144 loadIntConst(tree.elems.length());
2145 Item arr = makeNewArray(tree.pos(), tree.type, 1);
2146 int i = 0;
2147 for (List<JCExpression> l = tree.elems; l.nonEmpty(); l = l.tail) {
2148 arr.duplicate();
2149 loadIntConst(i);
2150 i++;
2151 genExpr(l.head, elemtype).load();
2152 items.makeIndexedItem(elemtype).store();
2153 }
2154 result = arr;
2155 } else {
2156 for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) {
2157 genExpr(l.head, syms.intType).load();
2158 }
2159 result = makeNewArray(tree.pos(), tree.type, tree.dims.length());
2160 }
2161 }
2162 //where
2163 /** Generate code to create an array with given element type and number
2164 * of dimensions.
2165 */
2166 Item makeNewArray(DiagnosticPosition pos, Type type, int ndims) {
2167 Type elemtype = types.elemtype(type);
2168 if (types.dimensions(type) > ClassFile.MAX_DIMENSIONS) {
2169 log.error(pos, Errors.LimitDimensions);
2170 nerrs++;
2171 }
2172 int elemcode = Code.arraycode(elemtype);
2173 if (elemcode == 0 || (elemcode == 1 && ndims == 1)) {
2174 code.emitAnewarray(makeRef(pos, elemtype), type);
2175 } else if (elemcode == 1) {
2176 code.emitMultianewarray(ndims, makeRef(pos, type), type);
2177 } else {
2178 code.emitNewarray(elemcode, type);
2179 }
2180 return items.makeStackItem(type);
2181 }
2182
2183 public void visitParens(JCParens tree) {
2184 result = genExpr(tree.expr, tree.expr.type);
2185 }
2186
2187 public void visitAssign(JCAssign tree) {
2188 Item l = genExpr(tree.lhs, tree.lhs.type);
2189 genExpr(tree.rhs, tree.lhs.type).load();
2190 Set<VarSymbol> tmpUnsetSymbols = unsetFieldsInfo.getUnsetFields(env.enclClass.sym, tree);
2191 code.currentUnsetFields = tmpUnsetSymbols != null ? tmpUnsetSymbols : code.currentUnsetFields;
2192 if (tree.rhs.type.hasTag(BOT)) {
2193 /* This is just a case of widening reference conversion that per 5.1.5 simply calls
2194 for "regarding a reference as having some other type in a manner that can be proved
2195 correct at compile time."
2196 */
2197 code.state.forceStackTop(tree.lhs.type);
2198 }
2199 result = items.makeAssignItem(l);
2200 }
2201
2202 public void visitAssignop(JCAssignOp tree) {
2203 OperatorSymbol operator = tree.operator;
2204 Item l;
2205 if (operator.opcode == string_add) {
2206 l = concat.makeConcat(tree);
2207 } else {
2208 // Generate code for first expression
2209 l = genExpr(tree.lhs, tree.lhs.type);
2210
2211 // If we have an increment of -32768 to +32767 of a local
2212 // int variable we can use an incr instruction instead of
2213 // proceeding further.
2214 if ((tree.hasTag(PLUS_ASG) || tree.hasTag(MINUS_ASG)) &&
2215 l instanceof LocalItem localItem &&
2216 tree.lhs.type.getTag().isSubRangeOf(INT) &&
2217 tree.rhs.type.getTag().isSubRangeOf(INT) &&
2218 tree.rhs.type.constValue() != null) {
2219 int ival = ((Number) tree.rhs.type.constValue()).intValue();
2220 if (tree.hasTag(MINUS_ASG)) ival = -ival;
2221 localItem.incr(ival);
2222 result = l;
2223 return;
2224 }
2225 // Otherwise, duplicate expression, load one copy
2226 // and complete binary operation.
2227 l.duplicate();
2228 l.coerce(operator.type.getParameterTypes().head).load();
2229 completeBinop(tree.lhs, tree.rhs, operator).coerce(tree.lhs.type);
2230 }
2231 result = items.makeAssignItem(l);
2232 }
2233
2234 public void visitUnary(JCUnary tree) {
2235 OperatorSymbol operator = tree.operator;
2236 if (tree.hasTag(NOT)) {
2237 CondItem od = genCond(tree.arg, false);
2238 result = od.negate();
2239 } else {
2240 Item od = genExpr(tree.arg, operator.type.getParameterTypes().head);
2241 switch (tree.getTag()) {
2242 case POS:
2243 result = od.load();
2244 break;
2245 case NEG:
2246 result = od.load();
2247 code.emitop0(operator.opcode);
2248 break;
2249 case COMPL:
2250 result = od.load();
2251 emitMinusOne(od.typecode);
2252 code.emitop0(operator.opcode);
2253 break;
2254 case PREINC: case PREDEC:
2255 od.duplicate();
2256 if (od instanceof LocalItem localItem &&
2257 (operator.opcode == iadd || operator.opcode == isub)) {
2258 localItem.incr(tree.hasTag(PREINC) ? 1 : -1);
2259 result = od;
2260 } else {
2261 od.load();
2262 code.emitop0(one(od.typecode));
2263 code.emitop0(operator.opcode);
2264 // Perform narrowing primitive conversion if byte,
2265 // char, or short. Fix for 4304655.
2266 if (od.typecode != INTcode &&
2267 Code.truncate(od.typecode) == INTcode)
2268 code.emitop0(int2byte + od.typecode - BYTEcode);
2269 result = items.makeAssignItem(od);
2270 }
2271 break;
2272 case POSTINC: case POSTDEC:
2273 od.duplicate();
2274 if (od instanceof LocalItem localItem &&
2275 (operator.opcode == iadd || operator.opcode == isub)) {
2276 Item res = od.load();
2277 localItem.incr(tree.hasTag(POSTINC) ? 1 : -1);
2278 result = res;
2279 } else {
2280 Item res = od.load();
2281 od.stash(od.typecode);
2282 code.emitop0(one(od.typecode));
2283 code.emitop0(operator.opcode);
2284 // Perform narrowing primitive conversion if byte,
2285 // char, or short. Fix for 4304655.
2286 if (od.typecode != INTcode &&
2287 Code.truncate(od.typecode) == INTcode)
2288 code.emitop0(int2byte + od.typecode - BYTEcode);
2289 od.store();
2290 result = res;
2291 }
2292 break;
2293 case NULLCHK:
2294 result = od.load();
2295 code.emitop0(dup);
2296 genNullCheck(tree);
2297 break;
2298 default:
2299 Assert.error();
2300 }
2301 }
2302 }
2303
2304 /** Generate a null check from the object value at stack top. */
2305 private void genNullCheck(JCTree tree) {
2306 code.statBegin(tree.pos);
2307 callMethod(tree.pos(), syms.objectsType, names.requireNonNull,
2308 List.of(syms.objectType), true);
2309 code.emitop0(pop);
2310 }
2311
2312 public void visitBinary(JCBinary tree) {
2313 OperatorSymbol operator = tree.operator;
2314 if (operator.opcode == string_add) {
2315 result = concat.makeConcat(tree);
2316 } else if (tree.hasTag(AND)) {
2317 CondItem lcond = genCond(tree.lhs, CRT_FLOW_CONTROLLER);
2318 if (!lcond.isFalse()) {
2319 Chain falseJumps = lcond.jumpFalse();
2320 code.resolve(lcond.trueJumps);
2321 CondItem rcond = genCond(tree.rhs, CRT_FLOW_TARGET);
2322 result = items.
2323 makeCondItem(rcond.opcode,
2324 rcond.trueJumps,
2325 Code.mergeChains(falseJumps,
2326 rcond.falseJumps));
2327 } else {
2328 result = lcond;
2329 }
2330 } else if (tree.hasTag(OR)) {
2331 CondItem lcond = genCond(tree.lhs, CRT_FLOW_CONTROLLER);
2332 if (!lcond.isTrue()) {
2333 Chain trueJumps = lcond.jumpTrue();
2334 code.resolve(lcond.falseJumps);
2335 CondItem rcond = genCond(tree.rhs, CRT_FLOW_TARGET);
2336 result = items.
2337 makeCondItem(rcond.opcode,
2338 Code.mergeChains(trueJumps, rcond.trueJumps),
2339 rcond.falseJumps);
2340 } else {
2341 result = lcond;
2342 }
2343 } else {
2344 Item od = genExpr(tree.lhs, operator.type.getParameterTypes().head);
2345 od.load();
2346 result = completeBinop(tree.lhs, tree.rhs, operator);
2347 }
2348 }
2349
2350
2351 /** Complete generating code for operation, with left operand
2352 * already on stack.
2353 * @param lhs The tree representing the left operand.
2354 * @param rhs The tree representing the right operand.
2355 * @param operator The operator symbol.
2356 */
2357 Item completeBinop(JCTree lhs, JCTree rhs, OperatorSymbol operator) {
2358 MethodType optype = (MethodType)operator.type;
2359 int opcode = operator.opcode;
2360 if (opcode >= if_icmpeq && opcode <= if_icmple &&
2361 rhs.type.constValue() instanceof Number number &&
2362 number.intValue() == 0) {
2363 opcode = opcode + (ifeq - if_icmpeq);
2364 } else if (opcode >= if_acmpeq && opcode <= if_acmpne &&
2365 TreeInfo.isNull(rhs)) {
2366 opcode = opcode + (if_acmp_null - if_acmpeq);
2367 } else {
2368 // The expected type of the right operand is
2369 // the second parameter type of the operator, except for
2370 // shifts with long shiftcount, where we convert the opcode
2371 // to a short shift and the expected type to int.
2372 Type rtype = operator.erasure(types).getParameterTypes().tail.head;
2373 if (opcode >= ishll && opcode <= lushrl) {
2374 opcode = opcode + (ishl - ishll);
2375 rtype = syms.intType;
2376 }
2377 // Generate code for right operand and load.
2378 genExpr(rhs, rtype).load();
2379 // If there are two consecutive opcode instructions,
2380 // emit the first now.
2381 if (opcode >= (1 << preShift)) {
2382 code.emitop0(opcode >> preShift);
2383 opcode = opcode & 0xFF;
2384 }
2385 }
2386 if (opcode >= ifeq && opcode <= if_acmpne ||
2387 opcode == if_acmp_null || opcode == if_acmp_nonnull) {
2388 return items.makeCondItem(opcode);
2389 } else {
2390 code.emitop0(opcode);
2391 return items.makeStackItem(optype.restype);
2392 }
2393 }
2394
2395 public void visitTypeCast(JCTypeCast tree) {
2396 result = genExpr(tree.expr, tree.clazz.type).load();
2397 setTypeAnnotationPositions(tree.pos);
2398 // Additional code is only needed if we cast to a reference type
2399 // which is not statically a supertype of the expression's type.
2400 // For basic types, the coerce(...) in genExpr(...) will do
2401 // the conversion.
2402 if (!tree.clazz.type.isPrimitive() &&
2403 !types.isSameType(tree.expr.type, tree.clazz.type) &&
2404 types.asSuper(tree.expr.type, tree.clazz.type.tsym) == null) {
2405 code.emitop2(checkcast, checkDimension(tree.pos(), tree.clazz.type), PoolWriter::putClass);
2406 }
2407 }
2408
2409 public void visitWildcard(JCWildcard tree) {
2410 throw new AssertionError(this.getClass().getName());
2411 }
2412
2413 public void visitTypeTest(JCInstanceOf tree) {
2414 genExpr(tree.expr, tree.expr.type).load();
2415 setTypeAnnotationPositions(tree.pos);
2416 code.emitop2(instanceof_, makeRef(tree.pos(), tree.pattern.type));
2417 result = items.makeStackItem(syms.booleanType);
2418 }
2419
2420 public void visitIndexed(JCArrayAccess tree) {
2421 genExpr(tree.indexed, tree.indexed.type).load();
2422 genExpr(tree.index, syms.intType).load();
2423 result = items.makeIndexedItem(tree.type);
2424 }
2425
2426 public void visitIdent(JCIdent tree) {
2427 Symbol sym = tree.sym;
2428 if (tree.name == names._this || tree.name == names._super) {
2429 Item res = tree.name == names._this
2430 ? items.makeThisItem()
2431 : items.makeSuperItem();
2432 if (sym.kind == MTH) {
2433 // Generate code to address the constructor.
2434 res.load();
2435 res = items.makeMemberItem(sym, true);
2436 }
2437 result = res;
2438 } else if (isInvokeDynamic(sym) || isConstantDynamic(sym)) {
2439 if (isConstantDynamic(sym)) {
2440 setTypeAnnotationPositions(tree.pos);
2441 }
2442 result = items.makeDynamicItem(sym);
2443 } else if (sym.kind == VAR && (sym.owner.kind == MTH || sym.owner.kind == VAR)) {
2444 result = items.makeLocalItem((VarSymbol)sym);
2445 } else if ((sym.flags() & STATIC) != 0) {
2446 if (!isAccessSuper(env.enclMethod))
2447 sym = binaryQualifier(sym, env.enclClass.type);
2448 result = items.makeStaticItem(sym);
2449 } else {
2450 items.makeThisItem().load();
2451 sym = binaryQualifier(sym, env.enclClass.type);
2452 result = items.makeMemberItem(sym, nonVirtualForPrivateAccess(sym));
2453 }
2454 }
2455
2456 //where
2457 private boolean nonVirtualForPrivateAccess(Symbol sym) {
2458 boolean useVirtual = target.hasVirtualPrivateInvoke() &&
2459 !disableVirtualizedPrivateInvoke;
2460 return !useVirtual && ((sym.flags() & PRIVATE) != 0);
2461 }
2462
2463 public void visitSelect(JCFieldAccess tree) {
2464 Symbol sym = tree.sym;
2465
2466 if (tree.name == names._class) {
2467 code.emitLdc((LoadableConstant)checkDimension(tree.pos(), tree.selected.type));
2468 result = items.makeStackItem(pt);
2469 return;
2470 }
2471
2472 Symbol ssym = TreeInfo.symbol(tree.selected);
2473
2474 // Are we selecting via super?
2475 boolean selectSuper =
2476 ssym != null && (ssym.kind == TYP || ssym.name == names._super);
2477
2478 // Are we accessing a member of the superclass in an access method
2479 // resulting from a qualified super?
2480 boolean accessSuper = isAccessSuper(env.enclMethod);
2481
2482 Item base = (selectSuper)
2483 ? items.makeSuperItem()
2484 : genExpr(tree.selected, tree.selected.type);
2485
2486 if (sym.kind == VAR && ((VarSymbol) sym).getConstValue() != null) {
2487 // We are seeing a variable that is constant but its selecting
2488 // expression is not.
2489 if ((sym.flags() & STATIC) != 0) {
2490 if (!selectSuper && (ssym == null || ssym.kind != TYP))
2491 base = base.load();
2492 base.drop();
2493 } else {
2494 base.load();
2495 genNullCheck(tree.selected);
2496 }
2497 result = items.
2498 makeImmediateItem(sym.type, ((VarSymbol) sym).getConstValue());
2499 } else {
2500 if (isInvokeDynamic(sym)) {
2501 result = items.makeDynamicItem(sym);
2502 return;
2503 } else {
2504 sym = binaryQualifier(sym, tree.selected.type);
2505 }
2506 if ((sym.flags() & STATIC) != 0) {
2507 if (!selectSuper && (ssym == null || ssym.kind != TYP))
2508 base = base.load();
2509 base.drop();
2510 result = items.makeStaticItem(sym);
2511 } else {
2512 base.load();
2513 if (sym == syms.lengthVar) {
2514 code.emitop0(arraylength);
2515 result = items.makeStackItem(syms.intType);
2516 } else {
2517 result = items.
2518 makeMemberItem(sym,
2519 nonVirtualForPrivateAccess(sym) ||
2520 selectSuper || accessSuper);
2521 }
2522 }
2523 }
2524 }
2525
2526 public boolean isInvokeDynamic(Symbol sym) {
2527 return sym.kind == MTH && ((MethodSymbol)sym).isDynamic();
2528 }
2529
2530 public void visitLiteral(JCLiteral tree) {
2531 if (tree.type.hasTag(BOT)) {
2532 code.emitop0(aconst_null);
2533 result = items.makeStackItem(tree.type);
2534 }
2535 else
2536 result = items.makeImmediateItem(tree.type, tree.value);
2537 }
2538
2539 public void visitLetExpr(LetExpr tree) {
2540 code.resolvePending();
2541
2542 int limit = code.nextreg;
2543 int prevLetExprStart = code.setLetExprStackPos(code.state.stacksize);
2544 try {
2545 genStats(tree.defs, env);
2546 } finally {
2547 code.setLetExprStackPos(prevLetExprStart);
2548 }
2549 result = genExpr(tree.expr, tree.expr.type).load();
2550 code.endScopes(limit);
2551 }
2552
2553 private void generateReferencesToPrunedTree(ClassSymbol classSymbol) {
2554 List<JCTree> prunedInfo = lower.prunedTree.get(classSymbol);
2555 if (prunedInfo != null) {
2556 for (JCTree prunedTree: prunedInfo) {
2557 prunedTree.accept(classReferenceVisitor);
2558 }
2559 }
2560 }
2561
2562 /* ************************************************************************
2563 * main method
2564 *************************************************************************/
2565
2566 /** Generate code for a class definition.
2567 * @param env The attribution environment that belongs to the
2568 * outermost class containing this class definition.
2569 * We need this for resolving some additional symbols.
2570 * @param cdef The tree representing the class definition.
2571 * @return True if code is generated with no errors.
2572 */
2573 public boolean genClass(Env<AttrContext> env, JCClassDecl cdef) {
2574 try {
2575 attrEnv = env;
2576 ClassSymbol c = cdef.sym;
2577 this.toplevel = env.toplevel;
2578 this.endPosTable = toplevel.endPositions;
2579 /* method normalizeDefs() can add references to external classes into the constant pool
2580 */
2581 cdef.defs = normalizeDefs(cdef.defs, c);
2582 generateReferencesToPrunedTree(c);
2583 Env<GenContext> localEnv = new Env<>(cdef, new GenContext());
2584 localEnv.toplevel = env.toplevel;
2585 localEnv.enclClass = cdef;
2586
2587 for (List<JCTree> l = cdef.defs; l.nonEmpty(); l = l.tail) {
2588 genDef(l.head, localEnv);
2589 }
2590 if (poolWriter.size() > PoolWriter.MAX_ENTRIES) {
2591 log.error(cdef.pos(), Errors.LimitPool);
2592 nerrs++;
2593 }
2594 if (nerrs != 0) {
2595 // if errors, discard code
2596 for (List<JCTree> l = cdef.defs; l.nonEmpty(); l = l.tail) {
2597 if (l.head.hasTag(METHODDEF))
2598 ((JCMethodDecl) l.head).sym.code = null;
2599 }
2600 }
2601 cdef.defs = List.nil(); // discard trees
2602 return nerrs == 0;
2603 } finally {
2604 // note: this method does NOT support recursion.
2605 attrEnv = null;
2606 this.env = null;
2607 toplevel = null;
2608 endPosTable = null;
2609 nerrs = 0;
2610 qualifiedSymbolCache.clear();
2611 }
2612 }
2613
2614 /* ************************************************************************
2615 * Auxiliary classes
2616 *************************************************************************/
2617
2618 /** An abstract class for finalizer generation.
2619 */
2620 abstract class GenFinalizer {
2621 /** Generate code to clean up when unwinding. */
2622 abstract void gen();
2623
2624 /** Generate code to clean up at last. */
2625 abstract void genLast();
2626
2627 /** Does this finalizer have some nontrivial cleanup to perform? */
2628 boolean hasFinalizer() { return true; }
2629
2630 /** Should be invoked after the try's body has been visited. */
2631 void afterBody() {}
2632 }
2633
2634 /** code generation contexts,
2635 * to be used as type parameter for environments.
2636 */
2637 final class GenContext {
2638
2639 /**
2640 * The top defined local variables for exit or continue branches to merge into.
2641 * It may contain uninitialized variables to be initialized by branched code,
2642 * so we cannot use Code.State.defined bits.
2643 */
2644 final int limit;
2645
2646 /** A chain for all unresolved jumps that exit the current environment.
2647 */
2648 Chain exit = null;
2649
2650 /** A chain for all unresolved jumps that continue in the
2651 * current environment.
2652 */
2653 Chain cont = null;
2654
2655 /** A closure that generates the finalizer of the current environment.
2656 * Only set for Synchronized and Try contexts.
2657 */
2658 GenFinalizer finalize = null;
2659
2660 /** Is this a switch statement? If so, allocate registers
2661 * even when the variable declaration is unreachable.
2662 */
2663 boolean isSwitch = false;
2664
2665 /** A list buffer containing all gaps in the finalizer range,
2666 * where a catch all exception should not apply.
2667 */
2668 ListBuffer<Integer> gaps = null;
2669
2670 GenContext() {
2671 var code = Gen.this.code;
2672 this.limit = code == null ? 0 : code.nextreg;
2673 }
2674
2675 /** Add given chain to exit chain.
2676 */
2677 void addExit(Chain c) {
2678 if (c != null) {
2679 c.state.defined.excludeFrom(limit);
2680 }
2681 exit = Code.mergeChains(c, exit);
2682 }
2683
2684 /** Add given chain to cont chain.
2685 */
2686 void addCont(Chain c) {
2687 if (c != null) {
2688 c.state.defined.excludeFrom(limit);
2689 }
2690 cont = Code.mergeChains(c, cont);
2691 }
2692 }
2693
2694 record PatternMatchingCatchConfiguration(Set<JCMethodInvocation> invocations,
2695 ListBuffer<int[]> ranges,
2696 JCCatch handler,
2697 State startState) {
2698 public PatternMatchingCatchConfiguration restart(State newState) {
2699 return new PatternMatchingCatchConfiguration(invocations(),
2700 new ListBuffer<int[]>(),
2701 handler(),
2702 newState);
2703 }
2704 }
2705 }