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