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src/share/classes/com/sun/tools/javac/jvm/Gen.java@859dc787b52b
src/share/classes/com/sun/tools/javac/jvm/Gen.java
Thu, 24 May 2018 16:48:51 +0800
- author
- aoqi
- date
- Thu, 24 May 2018 16:48:51 +0800
- changeset 3295
- 859dc787b52b
- parent 3000
- 4044eb07194d
- parent 2893
- ca5783d9a597
- child 3446
- e468915bad3a
- permissions
- -rw-r--r--
Merge
1 /*
2 * Copyright (c) 1999, 2015, 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 */
26 package com.sun.tools.javac.jvm;
28 import java.util.*;
30 import com.sun.tools.javac.util.*;
31 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
32 import com.sun.tools.javac.util.List;
33 import com.sun.tools.javac.code.*;
34 import com.sun.tools.javac.code.Attribute.TypeCompound;
35 import com.sun.tools.javac.code.Symbol.VarSymbol;
36 import com.sun.tools.javac.comp.*;
37 import com.sun.tools.javac.tree.*;
39 import com.sun.tools.javac.code.Symbol.*;
40 import com.sun.tools.javac.code.Type.*;
41 import com.sun.tools.javac.jvm.Code.*;
42 import com.sun.tools.javac.jvm.Items.*;
43 import com.sun.tools.javac.tree.EndPosTable;
44 import com.sun.tools.javac.tree.JCTree.*;
46 import static com.sun.tools.javac.code.Flags.*;
47 import static com.sun.tools.javac.code.Kinds.*;
48 import static com.sun.tools.javac.code.TypeTag.*;
49 import static com.sun.tools.javac.jvm.ByteCodes.*;
50 import static com.sun.tools.javac.jvm.CRTFlags.*;
51 import static com.sun.tools.javac.main.Option.*;
52 import static com.sun.tools.javac.tree.JCTree.Tag.*;
54 /** This pass maps flat Java (i.e. without inner classes) to bytecodes.
55 *
56 * <p><b>This is NOT part of any supported API.
57 * If you write code that depends on this, you do so at your own risk.
58 * This code and its internal interfaces are subject to change or
59 * deletion without notice.</b>
60 */
61 public class Gen extends JCTree.Visitor {
62 protected static final Context.Key<Gen> genKey =
63 new Context.Key<Gen>();
65 private final Log log;
66 private final Symtab syms;
67 private final Check chk;
68 private final Resolve rs;
69 private final TreeMaker make;
70 private final Names names;
71 private final Target target;
72 private final Type stringBufferType;
73 private final Map<Type,Symbol> stringBufferAppend;
74 private Name accessDollar;
75 private final Types types;
76 private final Lower lower;
77 private final Flow flow;
79 /** Switch: GJ mode?
80 */
81 private final boolean allowGenerics;
83 /** Set when Miranda method stubs are to be generated. */
84 private final boolean generateIproxies;
86 /** Format of stackmap tables to be generated. */
87 private final Code.StackMapFormat stackMap;
89 /** A type that serves as the expected type for all method expressions.
90 */
91 private final Type methodType;
93 public static Gen instance(Context context) {
94 Gen instance = context.get(genKey);
95 if (instance == null)
96 instance = new Gen(context);
97 return instance;
98 }
100 /** Constant pool, reset by genClass.
101 */
102 private Pool pool;
104 private final boolean typeAnnoAsserts;
106 protected Gen(Context context) {
107 context.put(genKey, this);
109 names = Names.instance(context);
110 log = Log.instance(context);
111 syms = Symtab.instance(context);
112 chk = Check.instance(context);
113 rs = Resolve.instance(context);
114 make = TreeMaker.instance(context);
115 target = Target.instance(context);
116 types = Types.instance(context);
117 methodType = new MethodType(null, null, null, syms.methodClass);
118 allowGenerics = Source.instance(context).allowGenerics();
119 stringBufferType = target.useStringBuilder()
120 ? syms.stringBuilderType
121 : syms.stringBufferType;
122 stringBufferAppend = new HashMap<Type,Symbol>();
123 accessDollar = names.
124 fromString("access" + target.syntheticNameChar());
125 flow = Flow.instance(context);
126 lower = Lower.instance(context);
128 Options options = Options.instance(context);
129 lineDebugInfo =
130 options.isUnset(G_CUSTOM) ||
131 options.isSet(G_CUSTOM, "lines");
132 varDebugInfo =
133 options.isUnset(G_CUSTOM)
134 ? options.isSet(G)
135 : options.isSet(G_CUSTOM, "vars");
136 genCrt = options.isSet(XJCOV);
137 debugCode = options.isSet("debugcode");
138 allowInvokedynamic = target.hasInvokedynamic() || options.isSet("invokedynamic");
139 pool = new Pool(types);
140 typeAnnoAsserts = options.isSet("TypeAnnotationAsserts");
142 generateIproxies =
143 target.requiresIproxy() ||
144 options.isSet("miranda");
146 if (target.generateStackMapTable()) {
147 // ignore cldc because we cannot have both stackmap formats
148 this.stackMap = StackMapFormat.JSR202;
149 } else {
150 if (target.generateCLDCStackmap()) {
151 this.stackMap = StackMapFormat.CLDC;
152 } else {
153 this.stackMap = StackMapFormat.NONE;
154 }
155 }
157 // by default, avoid jsr's for simple finalizers
158 int setjsrlimit = 50;
159 String jsrlimitString = options.get("jsrlimit");
160 if (jsrlimitString != null) {
161 try {
162 setjsrlimit = Integer.parseInt(jsrlimitString);
163 } catch (NumberFormatException ex) {
164 // ignore ill-formed numbers for jsrlimit
165 }
166 }
167 this.jsrlimit = setjsrlimit;
168 this.useJsrLocally = false; // reset in visitTry
169 }
171 /** Switches
172 */
173 private final boolean lineDebugInfo;
174 private final boolean varDebugInfo;
175 private final boolean genCrt;
176 private final boolean debugCode;
177 private final boolean allowInvokedynamic;
179 /** Default limit of (approximate) size of finalizer to inline.
180 * Zero means always use jsr. 100 or greater means never use
181 * jsr.
182 */
183 private final int jsrlimit;
185 /** True if jsr is used.
186 */
187 private boolean useJsrLocally;
189 /** Code buffer, set by genMethod.
190 */
191 private Code code;
193 /** Items structure, set by genMethod.
194 */
195 private Items items;
197 /** Environment for symbol lookup, set by genClass
198 */
199 private Env<AttrContext> attrEnv;
201 /** The top level tree.
202 */
203 private JCCompilationUnit toplevel;
205 /** The number of code-gen errors in this class.
206 */
207 private int nerrs = 0;
209 /** An object containing mappings of syntax trees to their
210 * ending source positions.
211 */
212 EndPosTable endPosTable;
214 /** Generate code to load an integer constant.
215 * @param n The integer to be loaded.
216 */
217 void loadIntConst(int n) {
218 items.makeImmediateItem(syms.intType, n).load();
219 }
221 /** The opcode that loads a zero constant of a given type code.
222 * @param tc The given type code (@see ByteCode).
223 */
224 public static int zero(int tc) {
225 switch(tc) {
226 case INTcode: case BYTEcode: case SHORTcode: case CHARcode:
227 return iconst_0;
228 case LONGcode:
229 return lconst_0;
230 case FLOATcode:
231 return fconst_0;
232 case DOUBLEcode:
233 return dconst_0;
234 default:
235 throw new AssertionError("zero");
236 }
237 }
239 /** The opcode that loads a one constant of a given type code.
240 * @param tc The given type code (@see ByteCode).
241 */
242 public static int one(int tc) {
243 return zero(tc) + 1;
244 }
246 /** Generate code to load -1 of the given type code (either int or long).
247 * @param tc The given type code (@see ByteCode).
248 */
249 void emitMinusOne(int tc) {
250 if (tc == LONGcode) {
251 items.makeImmediateItem(syms.longType, new Long(-1)).load();
252 } else {
253 code.emitop0(iconst_m1);
254 }
255 }
257 /** Construct a symbol to reflect the qualifying type that should
258 * appear in the byte code as per JLS 13.1.
259 *
260 * For {@literal target >= 1.2}: Clone a method with the qualifier as owner (except
261 * for those cases where we need to work around VM bugs).
262 *
263 * For {@literal target <= 1.1}: If qualified variable or method is defined in a
264 * non-accessible class, clone it with the qualifier class as owner.
265 *
266 * @param sym The accessed symbol
267 * @param site The qualifier's type.
268 */
269 Symbol binaryQualifier(Symbol sym, Type site) {
271 if (site.hasTag(ARRAY)) {
272 if (sym == syms.lengthVar ||
273 sym.owner != syms.arrayClass)
274 return sym;
275 // array clone can be qualified by the array type in later targets
276 Symbol qualifier = target.arrayBinaryCompatibility()
277 ? new ClassSymbol(Flags.PUBLIC, site.tsym.name,
278 site, syms.noSymbol)
279 : syms.objectType.tsym;
280 return sym.clone(qualifier);
281 }
283 if (sym.owner == site.tsym ||
284 (sym.flags() & (STATIC | SYNTHETIC)) == (STATIC | SYNTHETIC)) {
285 return sym;
286 }
287 if (!target.obeyBinaryCompatibility())
288 return rs.isAccessible(attrEnv, (TypeSymbol)sym.owner)
289 ? sym
290 : sym.clone(site.tsym);
292 if (!target.interfaceFieldsBinaryCompatibility()) {
293 if ((sym.owner.flags() & INTERFACE) != 0 && sym.kind == VAR)
294 return sym;
295 }
297 // leave alone methods inherited from Object
298 // JLS 13.1.
299 if (sym.owner == syms.objectType.tsym)
300 return sym;
302 if (!target.interfaceObjectOverridesBinaryCompatibility()) {
303 if ((sym.owner.flags() & INTERFACE) != 0 &&
304 syms.objectType.tsym.members().lookup(sym.name).scope != null)
305 return sym;
306 }
308 return sym.clone(site.tsym);
309 }
311 /** Insert a reference to given type in the constant pool,
312 * checking for an array with too many dimensions;
313 * return the reference's index.
314 * @param type The type for which a reference is inserted.
315 */
316 int makeRef(DiagnosticPosition pos, Type type) {
317 checkDimension(pos, type);
318 if (type.isAnnotated()) {
319 // Treat annotated types separately - we don't want
320 // to collapse all of them - at least for annotated
321 // exceptions.
322 // TODO: review this.
323 return pool.put((Object)type);
324 } else {
325 return pool.put(type.hasTag(CLASS) ? (Object)type.tsym : (Object)type);
326 }
327 }
329 /** Check if the given type is an array with too many dimensions.
330 */
331 private void checkDimension(DiagnosticPosition pos, Type t) {
332 switch (t.getTag()) {
333 case METHOD:
334 checkDimension(pos, t.getReturnType());
335 for (List<Type> args = t.getParameterTypes(); args.nonEmpty(); args = args.tail)
336 checkDimension(pos, args.head);
337 break;
338 case ARRAY:
339 if (types.dimensions(t) > ClassFile.MAX_DIMENSIONS) {
340 log.error(pos, "limit.dimensions");
341 nerrs++;
342 }
343 break;
344 default:
345 break;
346 }
347 }
349 /** Create a tempory variable.
350 * @param type The variable's type.
351 */
352 LocalItem makeTemp(Type type) {
353 VarSymbol v = new VarSymbol(Flags.SYNTHETIC,
354 names.empty,
355 type,
356 env.enclMethod.sym);
357 code.newLocal(v);
358 return items.makeLocalItem(v);
359 }
361 /** Generate code to call a non-private method or constructor.
362 * @param pos Position to be used for error reporting.
363 * @param site The type of which the method is a member.
364 * @param name The method's name.
365 * @param argtypes The method's argument types.
366 * @param isStatic A flag that indicates whether we call a
367 * static or instance method.
368 */
369 void callMethod(DiagnosticPosition pos,
370 Type site, Name name, List<Type> argtypes,
371 boolean isStatic) {
372 Symbol msym = rs.
373 resolveInternalMethod(pos, attrEnv, site, name, argtypes, null);
374 if (isStatic) items.makeStaticItem(msym).invoke();
375 else items.makeMemberItem(msym, name == names.init).invoke();
376 }
378 /** Is the given method definition an access method
379 * resulting from a qualified super? This is signified by an odd
380 * access code.
381 */
382 private boolean isAccessSuper(JCMethodDecl enclMethod) {
383 return
384 (enclMethod.mods.flags & SYNTHETIC) != 0 &&
385 isOddAccessName(enclMethod.name);
386 }
388 /** Does given name start with "access$" and end in an odd digit?
389 */
390 private boolean isOddAccessName(Name name) {
391 return
392 name.startsWith(accessDollar) &&
393 (name.getByteAt(name.getByteLength() - 1) & 1) == 1;
394 }
396 /* ************************************************************************
397 * Non-local exits
398 *************************************************************************/
400 /** Generate code to invoke the finalizer associated with given
401 * environment.
402 * Any calls to finalizers are appended to the environments `cont' chain.
403 * Mark beginning of gap in catch all range for finalizer.
404 */
405 void genFinalizer(Env<GenContext> env) {
406 if (code.isAlive() && env.info.finalize != null)
407 env.info.finalize.gen();
408 }
410 /** Generate code to call all finalizers of structures aborted by
411 * a non-local
412 * exit. Return target environment of the non-local exit.
413 * @param target The tree representing the structure that's aborted
414 * @param env The environment current at the non-local exit.
415 */
416 Env<GenContext> unwind(JCTree target, Env<GenContext> env) {
417 Env<GenContext> env1 = env;
418 while (true) {
419 genFinalizer(env1);
420 if (env1.tree == target) break;
421 env1 = env1.next;
422 }
423 return env1;
424 }
426 /** Mark end of gap in catch-all range for finalizer.
427 * @param env the environment which might contain the finalizer
428 * (if it does, env.info.gaps != null).
429 */
430 void endFinalizerGap(Env<GenContext> env) {
431 if (env.info.gaps != null && env.info.gaps.length() % 2 == 1)
432 env.info.gaps.append(code.curCP());
433 }
435 /** Mark end of all gaps in catch-all ranges for finalizers of environments
436 * lying between, and including to two environments.
437 * @param from the most deeply nested environment to mark
438 * @param to the least deeply nested environment to mark
439 */
440 void endFinalizerGaps(Env<GenContext> from, Env<GenContext> to) {
441 Env<GenContext> last = null;
442 while (last != to) {
443 endFinalizerGap(from);
444 last = from;
445 from = from.next;
446 }
447 }
449 /** Do any of the structures aborted by a non-local exit have
450 * finalizers that require an empty stack?
451 * @param target The tree representing the structure that's aborted
452 * @param env The environment current at the non-local exit.
453 */
454 boolean hasFinally(JCTree target, Env<GenContext> env) {
455 while (env.tree != target) {
456 if (env.tree.hasTag(TRY) && env.info.finalize.hasFinalizer())
457 return true;
458 env = env.next;
459 }
460 return false;
461 }
463 /* ************************************************************************
464 * Normalizing class-members.
465 *************************************************************************/
467 /** Distribute member initializer code into constructors and {@code <clinit>}
468 * method.
469 * @param defs The list of class member declarations.
470 * @param c The enclosing class.
471 */
472 List<JCTree> normalizeDefs(List<JCTree> defs, ClassSymbol c) {
473 ListBuffer<JCStatement> initCode = new ListBuffer<JCStatement>();
474 ListBuffer<Attribute.TypeCompound> initTAs = new ListBuffer<Attribute.TypeCompound>();
475 ListBuffer<JCStatement> clinitCode = new ListBuffer<JCStatement>();
476 ListBuffer<Attribute.TypeCompound> clinitTAs = new ListBuffer<Attribute.TypeCompound>();
477 ListBuffer<JCTree> methodDefs = new ListBuffer<JCTree>();
478 // Sort definitions into three listbuffers:
479 // - initCode for instance initializers
480 // - clinitCode for class initializers
481 // - methodDefs for method definitions
482 for (List<JCTree> l = defs; l.nonEmpty(); l = l.tail) {
483 JCTree def = l.head;
484 switch (def.getTag()) {
485 case BLOCK:
486 JCBlock block = (JCBlock)def;
487 if ((block.flags & STATIC) != 0)
488 clinitCode.append(block);
489 else if ((block.flags & SYNTHETIC) == 0)
490 initCode.append(block);
491 break;
492 case METHODDEF:
493 methodDefs.append(def);
494 break;
495 case VARDEF:
496 JCVariableDecl vdef = (JCVariableDecl) def;
497 VarSymbol sym = vdef.sym;
498 checkDimension(vdef.pos(), sym.type);
499 if (vdef.init != null) {
500 if ((sym.flags() & STATIC) == 0) {
501 // Always initialize instance variables.
502 JCStatement init = make.at(vdef.pos()).
503 Assignment(sym, vdef.init);
504 initCode.append(init);
505 endPosTable.replaceTree(vdef, init);
506 initTAs.addAll(getAndRemoveNonFieldTAs(sym));
507 } else if (sym.getConstValue() == null) {
508 // Initialize class (static) variables only if
509 // they are not compile-time constants.
510 JCStatement init = make.at(vdef.pos).
511 Assignment(sym, vdef.init);
512 clinitCode.append(init);
513 endPosTable.replaceTree(vdef, init);
514 clinitTAs.addAll(getAndRemoveNonFieldTAs(sym));
515 } else {
516 checkStringConstant(vdef.init.pos(), sym.getConstValue());
517 /* if the init contains a reference to an external class, add it to the
518 * constant's pool
519 */
520 vdef.init.accept(classReferenceVisitor);
521 }
522 }
523 break;
524 default:
525 Assert.error();
526 }
527 }
528 // Insert any instance initializers into all constructors.
529 if (initCode.length() != 0) {
530 List<JCStatement> inits = initCode.toList();
531 initTAs.addAll(c.getInitTypeAttributes());
532 List<Attribute.TypeCompound> initTAlist = initTAs.toList();
533 for (JCTree t : methodDefs) {
534 normalizeMethod((JCMethodDecl)t, inits, initTAlist);
535 }
536 }
537 // If there are class initializers, create a <clinit> method
538 // that contains them as its body.
539 if (clinitCode.length() != 0) {
540 MethodSymbol clinit = new MethodSymbol(
541 STATIC | (c.flags() & STRICTFP),
542 names.clinit,
543 new MethodType(
544 List.<Type>nil(), syms.voidType,
545 List.<Type>nil(), syms.methodClass),
546 c);
547 c.members().enter(clinit);
548 List<JCStatement> clinitStats = clinitCode.toList();
549 JCBlock block = make.at(clinitStats.head.pos()).Block(0, clinitStats);
550 block.endpos = TreeInfo.endPos(clinitStats.last());
551 methodDefs.append(make.MethodDef(clinit, block));
553 if (!clinitTAs.isEmpty())
554 clinit.appendUniqueTypeAttributes(clinitTAs.toList());
555 if (!c.getClassInitTypeAttributes().isEmpty())
556 clinit.appendUniqueTypeAttributes(c.getClassInitTypeAttributes());
557 }
558 // Return all method definitions.
559 return methodDefs.toList();
560 }
562 private List<Attribute.TypeCompound> getAndRemoveNonFieldTAs(VarSymbol sym) {
563 List<TypeCompound> tas = sym.getRawTypeAttributes();
564 ListBuffer<Attribute.TypeCompound> fieldTAs = new ListBuffer<Attribute.TypeCompound>();
565 ListBuffer<Attribute.TypeCompound> nonfieldTAs = new ListBuffer<Attribute.TypeCompound>();
566 for (TypeCompound ta : tas) {
567 if (ta.getPosition().type == TargetType.FIELD) {
568 fieldTAs.add(ta);
569 } else {
570 if (typeAnnoAsserts) {
571 Assert.error("Type annotation does not have a valid positior");
572 }
574 nonfieldTAs.add(ta);
575 }
576 }
577 sym.setTypeAttributes(fieldTAs.toList());
578 return nonfieldTAs.toList();
579 }
581 /** Check a constant value and report if it is a string that is
582 * too large.
583 */
584 private void checkStringConstant(DiagnosticPosition pos, Object constValue) {
585 if (nerrs != 0 || // only complain about a long string once
586 constValue == null ||
587 !(constValue instanceof String) ||
588 ((String)constValue).length() < Pool.MAX_STRING_LENGTH)
589 return;
590 log.error(pos, "limit.string");
591 nerrs++;
592 }
594 /** Insert instance initializer code into initial constructor.
595 * @param md The tree potentially representing a
596 * constructor's definition.
597 * @param initCode The list of instance initializer statements.
598 * @param initTAs Type annotations from the initializer expression.
599 */
600 void normalizeMethod(JCMethodDecl md, List<JCStatement> initCode, List<TypeCompound> initTAs) {
601 if (md.name == names.init && TreeInfo.isInitialConstructor(md)) {
602 // We are seeing a constructor that does not call another
603 // constructor of the same class.
604 List<JCStatement> stats = md.body.stats;
605 ListBuffer<JCStatement> newstats = new ListBuffer<JCStatement>();
607 if (stats.nonEmpty()) {
608 // Copy initializers of synthetic variables generated in
609 // the translation of inner classes.
610 while (TreeInfo.isSyntheticInit(stats.head)) {
611 newstats.append(stats.head);
612 stats = stats.tail;
613 }
614 // Copy superclass constructor call
615 newstats.append(stats.head);
616 stats = stats.tail;
617 // Copy remaining synthetic initializers.
618 while (stats.nonEmpty() &&
619 TreeInfo.isSyntheticInit(stats.head)) {
620 newstats.append(stats.head);
621 stats = stats.tail;
622 }
623 // Now insert the initializer code.
624 newstats.appendList(initCode);
625 // And copy all remaining statements.
626 while (stats.nonEmpty()) {
627 newstats.append(stats.head);
628 stats = stats.tail;
629 }
630 }
631 md.body.stats = newstats.toList();
632 if (md.body.endpos == Position.NOPOS)
633 md.body.endpos = TreeInfo.endPos(md.body.stats.last());
635 md.sym.appendUniqueTypeAttributes(initTAs);
636 }
637 }
639 /* ********************************************************************
640 * Adding miranda methods
641 *********************************************************************/
643 /** Add abstract methods for all methods defined in one of
644 * the interfaces of a given class,
645 * provided they are not already implemented in the class.
646 *
647 * @param c The class whose interfaces are searched for methods
648 * for which Miranda methods should be added.
649 */
650 void implementInterfaceMethods(ClassSymbol c) {
651 implementInterfaceMethods(c, c);
652 }
654 /** Add abstract methods for all methods defined in one of
655 * the interfaces of a given class,
656 * provided they are not already implemented in the class.
657 *
658 * @param c The class whose interfaces are searched for methods
659 * for which Miranda methods should be added.
660 * @param site The class in which a definition may be needed.
661 */
662 void implementInterfaceMethods(ClassSymbol c, ClassSymbol site) {
663 for (List<Type> l = types.interfaces(c.type); l.nonEmpty(); l = l.tail) {
664 ClassSymbol i = (ClassSymbol)l.head.tsym;
665 for (Scope.Entry e = i.members().elems;
666 e != null;
667 e = e.sibling)
668 {
669 if (e.sym.kind == MTH && (e.sym.flags() & STATIC) == 0)
670 {
671 MethodSymbol absMeth = (MethodSymbol)e.sym;
672 MethodSymbol implMeth = absMeth.binaryImplementation(site, types);
673 if (implMeth == null)
674 addAbstractMethod(site, absMeth);
675 else if ((implMeth.flags() & IPROXY) != 0)
676 adjustAbstractMethod(site, implMeth, absMeth);
677 }
678 }
679 implementInterfaceMethods(i, site);
680 }
681 }
683 /** Add an abstract methods to a class
684 * which implicitly implements a method defined in some interface
685 * implemented by the class. These methods are called "Miranda methods".
686 * Enter the newly created method into its enclosing class scope.
687 * Note that it is not entered into the class tree, as the emitter
688 * doesn't need to see it there to emit an abstract method.
689 *
690 * @param c The class to which the Miranda method is added.
691 * @param m The interface method symbol for which a Miranda method
692 * is added.
693 */
694 private void addAbstractMethod(ClassSymbol c,
695 MethodSymbol m) {
696 MethodSymbol absMeth = new MethodSymbol(
697 m.flags() | IPROXY | SYNTHETIC, m.name,
698 m.type, // was c.type.memberType(m), but now only !generics supported
699 c);
700 c.members().enter(absMeth); // add to symbol table
701 }
703 private void adjustAbstractMethod(ClassSymbol c,
704 MethodSymbol pm,
705 MethodSymbol im) {
706 MethodType pmt = (MethodType)pm.type;
707 Type imt = types.memberType(c.type, im);
708 pmt.thrown = chk.intersect(pmt.getThrownTypes(), imt.getThrownTypes());
709 }
711 /* ************************************************************************
712 * Traversal methods
713 *************************************************************************/
715 /** Visitor argument: The current environment.
716 */
717 Env<GenContext> env;
719 /** Visitor argument: The expected type (prototype).
720 */
721 Type pt;
723 /** Visitor result: The item representing the computed value.
724 */
725 Item result;
727 /** Visitor method: generate code for a definition, catching and reporting
728 * any completion failures.
729 * @param tree The definition to be visited.
730 * @param env The environment current at the definition.
731 */
732 public void genDef(JCTree tree, Env<GenContext> env) {
733 Env<GenContext> prevEnv = this.env;
734 try {
735 this.env = env;
736 tree.accept(this);
737 } catch (CompletionFailure ex) {
738 chk.completionError(tree.pos(), ex);
739 } finally {
740 this.env = prevEnv;
741 }
742 }
744 /** Derived visitor method: check whether CharacterRangeTable
745 * should be emitted, if so, put a new entry into CRTable
746 * and call method to generate bytecode.
747 * If not, just call method to generate bytecode.
748 * @see #genStat(JCTree, Env)
749 *
750 * @param tree The tree to be visited.
751 * @param env The environment to use.
752 * @param crtFlags The CharacterRangeTable flags
753 * indicating type of the entry.
754 */
755 public void genStat(JCTree tree, Env<GenContext> env, int crtFlags) {
756 if (!genCrt) {
757 genStat(tree, env);
758 return;
759 }
760 int startpc = code.curCP();
761 genStat(tree, env);
762 if (tree.hasTag(Tag.BLOCK)) crtFlags |= CRT_BLOCK;
763 code.crt.put(tree, crtFlags, startpc, code.curCP());
764 }
766 /** Derived visitor method: generate code for a statement.
767 */
768 public void genStat(JCTree tree, Env<GenContext> env) {
769 if (code.isAlive()) {
770 code.statBegin(tree.pos);
771 genDef(tree, env);
772 } else if (env.info.isSwitch && tree.hasTag(VARDEF)) {
773 // variables whose declarations are in a switch
774 // can be used even if the decl is unreachable.
775 code.newLocal(((JCVariableDecl) tree).sym);
776 }
777 }
779 /** Derived visitor method: check whether CharacterRangeTable
780 * should be emitted, if so, put a new entry into CRTable
781 * and call method to generate bytecode.
782 * If not, just call method to generate bytecode.
783 * @see #genStats(List, Env)
784 *
785 * @param trees The list of trees to be visited.
786 * @param env The environment to use.
787 * @param crtFlags The CharacterRangeTable flags
788 * indicating type of the entry.
789 */
790 public void genStats(List<JCStatement> trees, Env<GenContext> env, int crtFlags) {
791 if (!genCrt) {
792 genStats(trees, env);
793 return;
794 }
795 if (trees.length() == 1) { // mark one statement with the flags
796 genStat(trees.head, env, crtFlags | CRT_STATEMENT);
797 } else {
798 int startpc = code.curCP();
799 genStats(trees, env);
800 code.crt.put(trees, crtFlags, startpc, code.curCP());
801 }
802 }
804 /** Derived visitor method: generate code for a list of statements.
805 */
806 public void genStats(List<? extends JCTree> trees, Env<GenContext> env) {
807 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
808 genStat(l.head, env, CRT_STATEMENT);
809 }
811 /** Derived visitor method: check whether CharacterRangeTable
812 * should be emitted, if so, put a new entry into CRTable
813 * and call method to generate bytecode.
814 * If not, just call method to generate bytecode.
815 * @see #genCond(JCTree,boolean)
816 *
817 * @param tree The tree to be visited.
818 * @param crtFlags The CharacterRangeTable flags
819 * indicating type of the entry.
820 */
821 public CondItem genCond(JCTree tree, int crtFlags) {
822 if (!genCrt) return genCond(tree, false);
823 int startpc = code.curCP();
824 CondItem item = genCond(tree, (crtFlags & CRT_FLOW_CONTROLLER) != 0);
825 code.crt.put(tree, crtFlags, startpc, code.curCP());
826 return item;
827 }
829 /** Derived visitor method: generate code for a boolean
830 * expression in a control-flow context.
831 * @param _tree The expression to be visited.
832 * @param markBranches The flag to indicate that the condition is
833 * a flow controller so produced conditions
834 * should contain a proper tree to generate
835 * CharacterRangeTable branches for them.
836 */
837 public CondItem genCond(JCTree _tree, boolean markBranches) {
838 JCTree inner_tree = TreeInfo.skipParens(_tree);
839 if (inner_tree.hasTag(CONDEXPR)) {
840 JCConditional tree = (JCConditional)inner_tree;
841 CondItem cond = genCond(tree.cond, CRT_FLOW_CONTROLLER);
842 if (cond.isTrue()) {
843 code.resolve(cond.trueJumps);
844 CondItem result = genCond(tree.truepart, CRT_FLOW_TARGET);
845 if (markBranches) result.tree = tree.truepart;
846 return result;
847 }
848 if (cond.isFalse()) {
849 code.resolve(cond.falseJumps);
850 CondItem result = genCond(tree.falsepart, CRT_FLOW_TARGET);
851 if (markBranches) result.tree = tree.falsepart;
852 return result;
853 }
854 Chain secondJumps = cond.jumpFalse();
855 code.resolve(cond.trueJumps);
856 CondItem first = genCond(tree.truepart, CRT_FLOW_TARGET);
857 if (markBranches) first.tree = tree.truepart;
858 Chain falseJumps = first.jumpFalse();
859 code.resolve(first.trueJumps);
860 Chain trueJumps = code.branch(goto_);
861 code.resolve(secondJumps);
862 CondItem second = genCond(tree.falsepart, CRT_FLOW_TARGET);
863 CondItem result = items.makeCondItem(second.opcode,
864 Code.mergeChains(trueJumps, second.trueJumps),
865 Code.mergeChains(falseJumps, second.falseJumps));
866 if (markBranches) result.tree = tree.falsepart;
867 return result;
868 } else {
869 CondItem result = genExpr(_tree, syms.booleanType).mkCond();
870 if (markBranches) result.tree = _tree;
871 return result;
872 }
873 }
875 /** Visitor class for expressions which might be constant expressions.
876 * This class is a subset of TreeScanner. Intended to visit trees pruned by
877 * Lower as long as constant expressions looking for references to any
878 * ClassSymbol. Any such reference will be added to the constant pool so
879 * automated tools can detect class dependencies better.
880 */
881 class ClassReferenceVisitor extends JCTree.Visitor {
883 @Override
884 public void visitTree(JCTree tree) {}
886 @Override
887 public void visitBinary(JCBinary tree) {
888 tree.lhs.accept(this);
889 tree.rhs.accept(this);
890 }
892 @Override
893 public void visitSelect(JCFieldAccess tree) {
894 if (tree.selected.type.hasTag(CLASS)) {
895 makeRef(tree.selected.pos(), tree.selected.type);
896 }
897 }
899 @Override
900 public void visitIdent(JCIdent tree) {
901 if (tree.sym.owner instanceof ClassSymbol) {
902 pool.put(tree.sym.owner);
903 }
904 }
906 @Override
907 public void visitConditional(JCConditional tree) {
908 tree.cond.accept(this);
909 tree.truepart.accept(this);
910 tree.falsepart.accept(this);
911 }
913 @Override
914 public void visitUnary(JCUnary tree) {
915 tree.arg.accept(this);
916 }
918 @Override
919 public void visitParens(JCParens tree) {
920 tree.expr.accept(this);
921 }
923 @Override
924 public void visitTypeCast(JCTypeCast tree) {
925 tree.expr.accept(this);
926 }
927 }
929 private ClassReferenceVisitor classReferenceVisitor = new ClassReferenceVisitor();
931 /** Visitor method: generate code for an expression, catching and reporting
932 * any completion failures.
933 * @param tree The expression to be visited.
934 * @param pt The expression's expected type (proto-type).
935 */
936 public Item genExpr(JCTree tree, Type pt) {
937 Type prevPt = this.pt;
938 try {
939 if (tree.type.constValue() != null) {
940 // Short circuit any expressions which are constants
941 tree.accept(classReferenceVisitor);
942 checkStringConstant(tree.pos(), tree.type.constValue());
943 result = items.makeImmediateItem(tree.type, tree.type.constValue());
944 } else {
945 this.pt = pt;
946 tree.accept(this);
947 }
948 return result.coerce(pt);
949 } catch (CompletionFailure ex) {
950 chk.completionError(tree.pos(), ex);
951 code.state.stacksize = 1;
952 return items.makeStackItem(pt);
953 } finally {
954 this.pt = prevPt;
955 }
956 }
958 /** Derived visitor method: generate code for a list of method arguments.
959 * @param trees The argument expressions to be visited.
960 * @param pts The expression's expected types (i.e. the formal parameter
961 * types of the invoked method).
962 */
963 public void genArgs(List<JCExpression> trees, List<Type> pts) {
964 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail) {
965 genExpr(l.head, pts.head).load();
966 pts = pts.tail;
967 }
968 // require lists be of same length
969 Assert.check(pts.isEmpty());
970 }
972 /* ************************************************************************
973 * Visitor methods for statements and definitions
974 *************************************************************************/
976 /** Thrown when the byte code size exceeds limit.
977 */
978 public static class CodeSizeOverflow extends RuntimeException {
979 private static final long serialVersionUID = 0;
980 public CodeSizeOverflow() {}
981 }
983 public void visitMethodDef(JCMethodDecl tree) {
984 // Create a new local environment that points pack at method
985 // definition.
986 Env<GenContext> localEnv = env.dup(tree);
987 localEnv.enclMethod = tree;
988 // The expected type of every return statement in this method
989 // is the method's return type.
990 this.pt = tree.sym.erasure(types).getReturnType();
992 checkDimension(tree.pos(), tree.sym.erasure(types));
993 genMethod(tree, localEnv, false);
994 }
995 //where
996 /** Generate code for a method.
997 * @param tree The tree representing the method definition.
998 * @param env The environment current for the method body.
999 * @param fatcode A flag that indicates whether all jumps are
1000 * within 32K. We first invoke this method under
1001 * the assumption that fatcode == false, i.e. all
1002 * jumps are within 32K. If this fails, fatcode
1003 * is set to true and we try again.
1004 */
1005 void genMethod(JCMethodDecl tree, Env<GenContext> env, boolean fatcode) {
1006 MethodSymbol meth = tree.sym;
1007 int extras = 0;
1008 // Count up extra parameters
1009 if (meth.isConstructor()) {
1010 extras++;
1011 if (meth.enclClass().isInner() &&
1012 !meth.enclClass().isStatic()) {
1013 extras++;
1014 }
1015 } else if ((tree.mods.flags & STATIC) == 0) {
1016 extras++;
1017 }
1018 // System.err.println("Generating " + meth + " in " + meth.owner); //DEBUG
1019 if (Code.width(types.erasure(env.enclMethod.sym.type).getParameterTypes()) + extras >
1020 ClassFile.MAX_PARAMETERS) {
1021 log.error(tree.pos(), "limit.parameters");
1022 nerrs++;
1023 }
1025 else if (tree.body != null) {
1026 // Create a new code structure and initialize it.
1027 int startpcCrt = initCode(tree, env, fatcode);
1029 try {
1030 genStat(tree.body, env);
1031 } catch (CodeSizeOverflow e) {
1032 // Failed due to code limit, try again with jsr/ret
1033 startpcCrt = initCode(tree, env, fatcode);
1034 genStat(tree.body, env);
1035 }
1037 if (code.state.stacksize != 0) {
1038 log.error(tree.body.pos(), "stack.sim.error", tree);
1039 throw new AssertionError();
1040 }
1042 // If last statement could complete normally, insert a
1043 // return at the end.
1044 if (code.isAlive()) {
1045 code.statBegin(TreeInfo.endPos(tree.body));
1046 if (env.enclMethod == null ||
1047 env.enclMethod.sym.type.getReturnType().hasTag(VOID)) {
1048 code.emitop0(return_);
1049 } else {
1050 // sometime dead code seems alive (4415991);
1051 // generate a small loop instead
1052 int startpc = code.entryPoint();
1053 CondItem c = items.makeCondItem(goto_);
1054 code.resolve(c.jumpTrue(), startpc);
1055 }
1056 }
1057 if (genCrt)
1058 code.crt.put(tree.body,
1059 CRT_BLOCK,
1060 startpcCrt,
1061 code.curCP());
1063 code.endScopes(0);
1065 // If we exceeded limits, panic
1066 if (code.checkLimits(tree.pos(), log)) {
1067 nerrs++;
1068 return;
1069 }
1071 // If we generated short code but got a long jump, do it again
1072 // with fatCode = true.
1073 if (!fatcode && code.fatcode) genMethod(tree, env, true);
1075 // Clean up
1076 if(stackMap == StackMapFormat.JSR202) {
1077 code.lastFrame = null;
1078 code.frameBeforeLast = null;
1079 }
1081 // Compress exception table
1082 code.compressCatchTable();
1084 // Fill in type annotation positions for exception parameters
1085 code.fillExceptionParameterPositions();
1086 }
1087 }
1089 private int initCode(JCMethodDecl tree, Env<GenContext> env, boolean fatcode) {
1090 MethodSymbol meth = tree.sym;
1092 // Create a new code structure.
1093 meth.code = code = new Code(meth,
1094 fatcode,
1095 lineDebugInfo ? toplevel.lineMap : null,
1096 varDebugInfo,
1097 stackMap,
1098 debugCode,
1099 genCrt ? new CRTable(tree, env.toplevel.endPositions)
1100 : null,
1101 syms,
1102 types,
1103 pool);
1104 items = new Items(pool, code, syms, types);
1105 if (code.debugCode) {
1106 System.err.println(meth + " for body " + tree);
1107 }
1109 // If method is not static, create a new local variable address
1110 // for `this'.
1111 if ((tree.mods.flags & STATIC) == 0) {
1112 Type selfType = meth.owner.type;
1113 if (meth.isConstructor() && selfType != syms.objectType)
1114 selfType = UninitializedType.uninitializedThis(selfType);
1115 code.setDefined(
1116 code.newLocal(
1117 new VarSymbol(FINAL, names._this, selfType, meth.owner)));
1118 }
1120 // Mark all parameters as defined from the beginning of
1121 // the method.
1122 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
1123 checkDimension(l.head.pos(), l.head.sym.type);
1124 code.setDefined(code.newLocal(l.head.sym));
1125 }
1127 // Get ready to generate code for method body.
1128 int startpcCrt = genCrt ? code.curCP() : 0;
1129 code.entryPoint();
1131 // Suppress initial stackmap
1132 code.pendingStackMap = false;
1134 return startpcCrt;
1135 }
1137 public void visitVarDef(JCVariableDecl tree) {
1138 VarSymbol v = tree.sym;
1139 code.newLocal(v);
1140 if (tree.init != null) {
1141 checkStringConstant(tree.init.pos(), v.getConstValue());
1142 if (v.getConstValue() == null || varDebugInfo) {
1143 genExpr(tree.init, v.erasure(types)).load();
1144 items.makeLocalItem(v).store();
1145 }
1146 }
1147 checkDimension(tree.pos(), v.type);
1148 }
1150 public void visitSkip(JCSkip tree) {
1151 }
1153 public void visitBlock(JCBlock tree) {
1154 int limit = code.nextreg;
1155 Env<GenContext> localEnv = env.dup(tree, new GenContext());
1156 genStats(tree.stats, localEnv);
1157 // End the scope of all block-local variables in variable info.
1158 if (!env.tree.hasTag(METHODDEF)) {
1159 code.statBegin(tree.endpos);
1160 code.endScopes(limit);
1161 code.pendingStatPos = Position.NOPOS;
1162 }
1163 }
1165 public void visitDoLoop(JCDoWhileLoop tree) {
1166 genLoop(tree, tree.body, tree.cond, List.<JCExpressionStatement>nil(), false);
1167 }
1169 public void visitWhileLoop(JCWhileLoop tree) {
1170 genLoop(tree, tree.body, tree.cond, List.<JCExpressionStatement>nil(), true);
1171 }
1173 public void visitForLoop(JCForLoop tree) {
1174 int limit = code.nextreg;
1175 genStats(tree.init, env);
1176 genLoop(tree, tree.body, tree.cond, tree.step, true);
1177 code.endScopes(limit);
1178 }
1179 //where
1180 /** Generate code for a loop.
1181 * @param loop The tree representing the loop.
1182 * @param body The loop's body.
1183 * @param cond The loop's controling condition.
1184 * @param step "Step" statements to be inserted at end of
1185 * each iteration.
1186 * @param testFirst True if the loop test belongs before the body.
1187 */
1188 private void genLoop(JCStatement loop,
1189 JCStatement body,
1190 JCExpression cond,
1191 List<JCExpressionStatement> step,
1192 boolean testFirst) {
1193 Env<GenContext> loopEnv = env.dup(loop, new GenContext());
1194 int startpc = code.entryPoint();
1195 if (testFirst) { //while or for loop
1196 CondItem c;
1197 if (cond != null) {
1198 code.statBegin(cond.pos);
1199 c = genCond(TreeInfo.skipParens(cond), CRT_FLOW_CONTROLLER);
1200 } else {
1201 c = items.makeCondItem(goto_);
1202 }
1203 Chain loopDone = c.jumpFalse();
1204 code.resolve(c.trueJumps);
1205 genStat(body, loopEnv, CRT_STATEMENT | CRT_FLOW_TARGET);
1206 code.resolve(loopEnv.info.cont);
1207 genStats(step, loopEnv);
1208 code.resolve(code.branch(goto_), startpc);
1209 code.resolve(loopDone);
1210 } else {
1211 genStat(body, loopEnv, CRT_STATEMENT | CRT_FLOW_TARGET);
1212 code.resolve(loopEnv.info.cont);
1213 genStats(step, loopEnv);
1214 CondItem c;
1215 if (cond != null) {
1216 code.statBegin(cond.pos);
1217 c = genCond(TreeInfo.skipParens(cond), CRT_FLOW_CONTROLLER);
1218 } else {
1219 c = items.makeCondItem(goto_);
1220 }
1221 code.resolve(c.jumpTrue(), startpc);
1222 code.resolve(c.falseJumps);
1223 }
1224 code.resolve(loopEnv.info.exit);
1225 if (loopEnv.info.exit != null) {
1226 loopEnv.info.exit.state.defined.excludeFrom(code.nextreg);
1227 }
1228 }
1230 public void visitForeachLoop(JCEnhancedForLoop tree) {
1231 throw new AssertionError(); // should have been removed by Lower.
1232 }
1234 public void visitLabelled(JCLabeledStatement tree) {
1235 Env<GenContext> localEnv = env.dup(tree, new GenContext());
1236 genStat(tree.body, localEnv, CRT_STATEMENT);
1237 code.resolve(localEnv.info.exit);
1238 }
1240 public void visitSwitch(JCSwitch tree) {
1241 int limit = code.nextreg;
1242 Assert.check(!tree.selector.type.hasTag(CLASS));
1243 int startpcCrt = genCrt ? code.curCP() : 0;
1244 Item sel = genExpr(tree.selector, syms.intType);
1245 List<JCCase> cases = tree.cases;
1246 if (cases.isEmpty()) {
1247 // We are seeing: switch <sel> {}
1248 sel.load().drop();
1249 if (genCrt)
1250 code.crt.put(TreeInfo.skipParens(tree.selector),
1251 CRT_FLOW_CONTROLLER, startpcCrt, code.curCP());
1252 } else {
1253 // We are seeing a nonempty switch.
1254 sel.load();
1255 if (genCrt)
1256 code.crt.put(TreeInfo.skipParens(tree.selector),
1257 CRT_FLOW_CONTROLLER, startpcCrt, code.curCP());
1258 Env<GenContext> switchEnv = env.dup(tree, new GenContext());
1259 switchEnv.info.isSwitch = true;
1261 // Compute number of labels and minimum and maximum label values.
1262 // For each case, store its label in an array.
1263 int lo = Integer.MAX_VALUE; // minimum label.
1264 int hi = Integer.MIN_VALUE; // maximum label.
1265 int nlabels = 0; // number of labels.
1267 int[] labels = new int[cases.length()]; // the label array.
1268 int defaultIndex = -1; // the index of the default clause.
1270 List<JCCase> l = cases;
1271 for (int i = 0; i < labels.length; i++) {
1272 if (l.head.pat != null) {
1273 int val = ((Number)l.head.pat.type.constValue()).intValue();
1274 labels[i] = val;
1275 if (val < lo) lo = val;
1276 if (hi < val) hi = val;
1277 nlabels++;
1278 } else {
1279 Assert.check(defaultIndex == -1);
1280 defaultIndex = i;
1281 }
1282 l = l.tail;
1283 }
1285 // Determine whether to issue a tableswitch or a lookupswitch
1286 // instruction.
1287 long table_space_cost = 4 + ((long) hi - lo + 1); // words
1288 long table_time_cost = 3; // comparisons
1289 long lookup_space_cost = 3 + 2 * (long) nlabels;
1290 long lookup_time_cost = nlabels;
1291 int opcode =
1292 nlabels > 0 &&
1293 table_space_cost + 3 * table_time_cost <=
1294 lookup_space_cost + 3 * lookup_time_cost
1295 ?
1296 tableswitch : lookupswitch;
1298 int startpc = code.curCP(); // the position of the selector operation
1299 code.emitop0(opcode);
1300 code.align(4);
1301 int tableBase = code.curCP(); // the start of the jump table
1302 int[] offsets = null; // a table of offsets for a lookupswitch
1303 code.emit4(-1); // leave space for default offset
1304 if (opcode == tableswitch) {
1305 code.emit4(lo); // minimum label
1306 code.emit4(hi); // maximum label
1307 for (long i = lo; i <= hi; i++) { // leave space for jump table
1308 code.emit4(-1);
1309 }
1310 } else {
1311 code.emit4(nlabels); // number of labels
1312 for (int i = 0; i < nlabels; i++) {
1313 code.emit4(-1); code.emit4(-1); // leave space for lookup table
1314 }
1315 offsets = new int[labels.length];
1316 }
1317 Code.State stateSwitch = code.state.dup();
1318 code.markDead();
1320 // For each case do:
1321 l = cases;
1322 for (int i = 0; i < labels.length; i++) {
1323 JCCase c = l.head;
1324 l = l.tail;
1326 int pc = code.entryPoint(stateSwitch);
1327 // Insert offset directly into code or else into the
1328 // offsets table.
1329 if (i != defaultIndex) {
1330 if (opcode == tableswitch) {
1331 code.put4(
1332 tableBase + 4 * (labels[i] - lo + 3),
1333 pc - startpc);
1334 } else {
1335 offsets[i] = pc - startpc;
1336 }
1337 } else {
1338 code.put4(tableBase, pc - startpc);
1339 }
1341 // Generate code for the statements in this case.
1342 genStats(c.stats, switchEnv, CRT_FLOW_TARGET);
1343 }
1345 // Resolve all breaks.
1346 code.resolve(switchEnv.info.exit);
1348 // If we have not set the default offset, we do so now.
1349 if (code.get4(tableBase) == -1) {
1350 code.put4(tableBase, code.entryPoint(stateSwitch) - startpc);
1351 }
1353 if (opcode == tableswitch) {
1354 // Let any unfilled slots point to the default case.
1355 int defaultOffset = code.get4(tableBase);
1356 for (long i = lo; i <= hi; i++) {
1357 int t = (int)(tableBase + 4 * (i - lo + 3));
1358 if (code.get4(t) == -1)
1359 code.put4(t, defaultOffset);
1360 }
1361 } else {
1362 // Sort non-default offsets and copy into lookup table.
1363 if (defaultIndex >= 0)
1364 for (int i = defaultIndex; i < labels.length - 1; i++) {
1365 labels[i] = labels[i+1];
1366 offsets[i] = offsets[i+1];
1367 }
1368 if (nlabels > 0)
1369 qsort2(labels, offsets, 0, nlabels - 1);
1370 for (int i = 0; i < nlabels; i++) {
1371 int caseidx = tableBase + 8 * (i + 1);
1372 code.put4(caseidx, labels[i]);
1373 code.put4(caseidx + 4, offsets[i]);
1374 }
1375 }
1376 }
1377 code.endScopes(limit);
1378 }
1379 //where
1380 /** Sort (int) arrays of keys and values
1381 */
1382 static void qsort2(int[] keys, int[] values, int lo, int hi) {
1383 int i = lo;
1384 int j = hi;
1385 int pivot = keys[(i+j)/2];
1386 do {
1387 while (keys[i] < pivot) i++;
1388 while (pivot < keys[j]) j--;
1389 if (i <= j) {
1390 int temp1 = keys[i];
1391 keys[i] = keys[j];
1392 keys[j] = temp1;
1393 int temp2 = values[i];
1394 values[i] = values[j];
1395 values[j] = temp2;
1396 i++;
1397 j--;
1398 }
1399 } while (i <= j);
1400 if (lo < j) qsort2(keys, values, lo, j);
1401 if (i < hi) qsort2(keys, values, i, hi);
1402 }
1404 public void visitSynchronized(JCSynchronized tree) {
1405 int limit = code.nextreg;
1406 // Generate code to evaluate lock and save in temporary variable.
1407 final LocalItem lockVar = makeTemp(syms.objectType);
1408 genExpr(tree.lock, tree.lock.type).load().duplicate();
1409 lockVar.store();
1411 // Generate code to enter monitor.
1412 code.emitop0(monitorenter);
1413 code.state.lock(lockVar.reg);
1415 // Generate code for a try statement with given body, no catch clauses
1416 // in a new environment with the "exit-monitor" operation as finalizer.
1417 final Env<GenContext> syncEnv = env.dup(tree, new GenContext());
1418 syncEnv.info.finalize = new GenFinalizer() {
1419 void gen() {
1420 genLast();
1421 Assert.check(syncEnv.info.gaps.length() % 2 == 0);
1422 syncEnv.info.gaps.append(code.curCP());
1423 }
1424 void genLast() {
1425 if (code.isAlive()) {
1426 lockVar.load();
1427 code.emitop0(monitorexit);
1428 code.state.unlock(lockVar.reg);
1429 }
1430 }
1431 };
1432 syncEnv.info.gaps = new ListBuffer<Integer>();
1433 genTry(tree.body, List.<JCCatch>nil(), syncEnv);
1434 code.endScopes(limit);
1435 }
1437 public void visitTry(final JCTry tree) {
1438 // Generate code for a try statement with given body and catch clauses,
1439 // in a new environment which calls the finally block if there is one.
1440 final Env<GenContext> tryEnv = env.dup(tree, new GenContext());
1441 final Env<GenContext> oldEnv = env;
1442 if (!useJsrLocally) {
1443 useJsrLocally =
1444 (stackMap == StackMapFormat.NONE) &&
1445 (jsrlimit <= 0 ||
1446 jsrlimit < 100 &&
1447 estimateCodeComplexity(tree.finalizer)>jsrlimit);
1448 }
1449 tryEnv.info.finalize = new GenFinalizer() {
1450 void gen() {
1451 if (useJsrLocally) {
1452 if (tree.finalizer != null) {
1453 Code.State jsrState = code.state.dup();
1454 jsrState.push(Code.jsrReturnValue);
1455 tryEnv.info.cont =
1456 new Chain(code.emitJump(jsr),
1457 tryEnv.info.cont,
1458 jsrState);
1459 }
1460 Assert.check(tryEnv.info.gaps.length() % 2 == 0);
1461 tryEnv.info.gaps.append(code.curCP());
1462 } else {
1463 Assert.check(tryEnv.info.gaps.length() % 2 == 0);
1464 tryEnv.info.gaps.append(code.curCP());
1465 genLast();
1466 }
1467 }
1468 void genLast() {
1469 if (tree.finalizer != null)
1470 genStat(tree.finalizer, oldEnv, CRT_BLOCK);
1471 }
1472 boolean hasFinalizer() {
1473 return tree.finalizer != null;
1474 }
1475 };
1476 tryEnv.info.gaps = new ListBuffer<Integer>();
1477 genTry(tree.body, tree.catchers, tryEnv);
1478 }
1479 //where
1480 /** Generate code for a try or synchronized statement
1481 * @param body The body of the try or synchronized statement.
1482 * @param catchers The lis of catch clauses.
1483 * @param env the environment current for the body.
1484 */
1485 void genTry(JCTree body, List<JCCatch> catchers, Env<GenContext> env) {
1486 int limit = code.nextreg;
1487 int startpc = code.curCP();
1488 Code.State stateTry = code.state.dup();
1489 genStat(body, env, CRT_BLOCK);
1490 int endpc = code.curCP();
1491 boolean hasFinalizer =
1492 env.info.finalize != null &&
1493 env.info.finalize.hasFinalizer();
1494 List<Integer> gaps = env.info.gaps.toList();
1495 code.statBegin(TreeInfo.endPos(body));
1496 genFinalizer(env);
1497 code.statBegin(TreeInfo.endPos(env.tree));
1498 Chain exitChain = code.branch(goto_);
1499 endFinalizerGap(env);
1500 if (startpc != endpc) for (List<JCCatch> l = catchers; l.nonEmpty(); l = l.tail) {
1501 // start off with exception on stack
1502 code.entryPoint(stateTry, l.head.param.sym.type);
1503 genCatch(l.head, env, startpc, endpc, gaps);
1504 genFinalizer(env);
1505 if (hasFinalizer || l.tail.nonEmpty()) {
1506 code.statBegin(TreeInfo.endPos(env.tree));
1507 exitChain = Code.mergeChains(exitChain,
1508 code.branch(goto_));
1509 }
1510 endFinalizerGap(env);
1511 }
1512 if (hasFinalizer) {
1513 // Create a new register segement to avoid allocating
1514 // the same variables in finalizers and other statements.
1515 code.newRegSegment();
1517 // Add a catch-all clause.
1519 // start off with exception on stack
1520 int catchallpc = code.entryPoint(stateTry, syms.throwableType);
1522 // Register all exception ranges for catch all clause.
1523 // The range of the catch all clause is from the beginning
1524 // of the try or synchronized block until the present
1525 // code pointer excluding all gaps in the current
1526 // environment's GenContext.
1527 int startseg = startpc;
1528 while (env.info.gaps.nonEmpty()) {
1529 int endseg = env.info.gaps.next().intValue();
1530 registerCatch(body.pos(), startseg, endseg,
1531 catchallpc, 0);
1532 startseg = env.info.gaps.next().intValue();
1533 }
1534 code.statBegin(TreeInfo.finalizerPos(env.tree));
1535 code.markStatBegin();
1537 Item excVar = makeTemp(syms.throwableType);
1538 excVar.store();
1539 genFinalizer(env);
1540 excVar.load();
1541 registerCatch(body.pos(), startseg,
1542 env.info.gaps.next().intValue(),
1543 catchallpc, 0);
1544 code.emitop0(athrow);
1545 code.markDead();
1547 // If there are jsr's to this finalizer, ...
1548 if (env.info.cont != null) {
1549 // Resolve all jsr's.
1550 code.resolve(env.info.cont);
1552 // Mark statement line number
1553 code.statBegin(TreeInfo.finalizerPos(env.tree));
1554 code.markStatBegin();
1556 // Save return address.
1557 LocalItem retVar = makeTemp(syms.throwableType);
1558 retVar.store();
1560 // Generate finalizer code.
1561 env.info.finalize.genLast();
1563 // Return.
1564 code.emitop1w(ret, retVar.reg);
1565 code.markDead();
1566 }
1567 }
1568 // Resolve all breaks.
1569 code.resolve(exitChain);
1571 code.endScopes(limit);
1572 }
1574 /** Generate code for a catch clause.
1575 * @param tree The catch clause.
1576 * @param env The environment current in the enclosing try.
1577 * @param startpc Start pc of try-block.
1578 * @param endpc End pc of try-block.
1579 */
1580 void genCatch(JCCatch tree,
1581 Env<GenContext> env,
1582 int startpc, int endpc,
1583 List<Integer> gaps) {
1584 if (startpc != endpc) {
1585 List<JCExpression> subClauses = TreeInfo.isMultiCatch(tree) ?
1586 ((JCTypeUnion)tree.param.vartype).alternatives :
1587 List.of(tree.param.vartype);
1588 while (gaps.nonEmpty()) {
1589 for (JCExpression subCatch : subClauses) {
1590 int catchType = makeRef(tree.pos(), subCatch.type);
1591 int end = gaps.head.intValue();
1592 registerCatch(tree.pos(),
1593 startpc, end, code.curCP(),
1594 catchType);
1595 if (subCatch.type.isAnnotated()) {
1596 for (Attribute.TypeCompound tc :
1597 subCatch.type.getAnnotationMirrors()) {
1598 tc.position.type_index = catchType;
1599 }
1600 }
1601 }
1602 gaps = gaps.tail;
1603 startpc = gaps.head.intValue();
1604 gaps = gaps.tail;
1605 }
1606 if (startpc < endpc) {
1607 for (JCExpression subCatch : subClauses) {
1608 int catchType = makeRef(tree.pos(), subCatch.type);
1609 registerCatch(tree.pos(),
1610 startpc, endpc, code.curCP(),
1611 catchType);
1612 if (subCatch.type.isAnnotated()) {
1613 for (Attribute.TypeCompound tc :
1614 subCatch.type.getAnnotationMirrors()) {
1615 tc.position.type_index = catchType;
1616 }
1617 }
1618 }
1619 }
1620 VarSymbol exparam = tree.param.sym;
1621 code.statBegin(tree.pos);
1622 code.markStatBegin();
1623 int limit = code.nextreg;
1624 int exlocal = code.newLocal(exparam);
1625 items.makeLocalItem(exparam).store();
1626 code.statBegin(TreeInfo.firstStatPos(tree.body));
1627 genStat(tree.body, env, CRT_BLOCK);
1628 code.endScopes(limit);
1629 code.statBegin(TreeInfo.endPos(tree.body));
1630 }
1631 }
1633 /** Register a catch clause in the "Exceptions" code-attribute.
1634 */
1635 void registerCatch(DiagnosticPosition pos,
1636 int startpc, int endpc,
1637 int handler_pc, int catch_type) {
1638 char startpc1 = (char)startpc;
1639 char endpc1 = (char)endpc;
1640 char handler_pc1 = (char)handler_pc;
1641 if (startpc1 == startpc &&
1642 endpc1 == endpc &&
1643 handler_pc1 == handler_pc) {
1644 code.addCatch(startpc1, endpc1, handler_pc1,
1645 (char)catch_type);
1646 } else {
1647 if (!useJsrLocally && !target.generateStackMapTable()) {
1648 useJsrLocally = true;
1649 throw new CodeSizeOverflow();
1650 } else {
1651 log.error(pos, "limit.code.too.large.for.try.stmt");
1652 nerrs++;
1653 }
1654 }
1655 }
1657 /** Very roughly estimate the number of instructions needed for
1658 * the given tree.
1659 */
1660 int estimateCodeComplexity(JCTree tree) {
1661 if (tree == null) return 0;
1662 class ComplexityScanner extends TreeScanner {
1663 int complexity = 0;
1664 public void scan(JCTree tree) {
1665 if (complexity > jsrlimit) return;
1666 super.scan(tree);
1667 }
1668 public void visitClassDef(JCClassDecl tree) {}
1669 public void visitDoLoop(JCDoWhileLoop tree)
1670 { super.visitDoLoop(tree); complexity++; }
1671 public void visitWhileLoop(JCWhileLoop tree)
1672 { super.visitWhileLoop(tree); complexity++; }
1673 public void visitForLoop(JCForLoop tree)
1674 { super.visitForLoop(tree); complexity++; }
1675 public void visitSwitch(JCSwitch tree)
1676 { super.visitSwitch(tree); complexity+=5; }
1677 public void visitCase(JCCase tree)
1678 { super.visitCase(tree); complexity++; }
1679 public void visitSynchronized(JCSynchronized tree)
1680 { super.visitSynchronized(tree); complexity+=6; }
1681 public void visitTry(JCTry tree)
1682 { super.visitTry(tree);
1683 if (tree.finalizer != null) complexity+=6; }
1684 public void visitCatch(JCCatch tree)
1685 { super.visitCatch(tree); complexity+=2; }
1686 public void visitConditional(JCConditional tree)
1687 { super.visitConditional(tree); complexity+=2; }
1688 public void visitIf(JCIf tree)
1689 { super.visitIf(tree); complexity+=2; }
1690 // note: for break, continue, and return we don't take unwind() into account.
1691 public void visitBreak(JCBreak tree)
1692 { super.visitBreak(tree); complexity+=1; }
1693 public void visitContinue(JCContinue tree)
1694 { super.visitContinue(tree); complexity+=1; }
1695 public void visitReturn(JCReturn tree)
1696 { super.visitReturn(tree); complexity+=1; }
1697 public void visitThrow(JCThrow tree)
1698 { super.visitThrow(tree); complexity+=1; }
1699 public void visitAssert(JCAssert tree)
1700 { super.visitAssert(tree); complexity+=5; }
1701 public void visitApply(JCMethodInvocation tree)
1702 { super.visitApply(tree); complexity+=2; }
1703 public void visitNewClass(JCNewClass tree)
1704 { scan(tree.encl); scan(tree.args); complexity+=2; }
1705 public void visitNewArray(JCNewArray tree)
1706 { super.visitNewArray(tree); complexity+=5; }
1707 public void visitAssign(JCAssign tree)
1708 { super.visitAssign(tree); complexity+=1; }
1709 public void visitAssignop(JCAssignOp tree)
1710 { super.visitAssignop(tree); complexity+=2; }
1711 public void visitUnary(JCUnary tree)
1712 { complexity+=1;
1713 if (tree.type.constValue() == null) super.visitUnary(tree); }
1714 public void visitBinary(JCBinary tree)
1715 { complexity+=1;
1716 if (tree.type.constValue() == null) super.visitBinary(tree); }
1717 public void visitTypeTest(JCInstanceOf tree)
1718 { super.visitTypeTest(tree); complexity+=1; }
1719 public void visitIndexed(JCArrayAccess tree)
1720 { super.visitIndexed(tree); complexity+=1; }
1721 public void visitSelect(JCFieldAccess tree)
1722 { super.visitSelect(tree);
1723 if (tree.sym.kind == VAR) complexity+=1; }
1724 public void visitIdent(JCIdent tree) {
1725 if (tree.sym.kind == VAR) {
1726 complexity+=1;
1727 if (tree.type.constValue() == null &&
1728 tree.sym.owner.kind == TYP)
1729 complexity+=1;
1730 }
1731 }
1732 public void visitLiteral(JCLiteral tree)
1733 { complexity+=1; }
1734 public void visitTree(JCTree tree) {}
1735 public void visitWildcard(JCWildcard tree) {
1736 throw new AssertionError(this.getClass().getName());
1737 }
1738 }
1739 ComplexityScanner scanner = new ComplexityScanner();
1740 tree.accept(scanner);
1741 return scanner.complexity;
1742 }
1744 public void visitIf(JCIf tree) {
1745 int limit = code.nextreg;
1746 Chain thenExit = null;
1747 CondItem c = genCond(TreeInfo.skipParens(tree.cond),
1748 CRT_FLOW_CONTROLLER);
1749 Chain elseChain = c.jumpFalse();
1750 if (!c.isFalse()) {
1751 code.resolve(c.trueJumps);
1752 genStat(tree.thenpart, env, CRT_STATEMENT | CRT_FLOW_TARGET);
1753 thenExit = code.branch(goto_);
1754 }
1755 if (elseChain != null) {
1756 code.resolve(elseChain);
1757 if (tree.elsepart != null) {
1758 genStat(tree.elsepart, env,CRT_STATEMENT | CRT_FLOW_TARGET);
1759 }
1760 }
1761 code.resolve(thenExit);
1762 code.endScopes(limit);
1763 }
1765 public void visitExec(JCExpressionStatement tree) {
1766 // Optimize x++ to ++x and x-- to --x.
1767 JCExpression e = tree.expr;
1768 switch (e.getTag()) {
1769 case POSTINC:
1770 ((JCUnary) e).setTag(PREINC);
1771 break;
1772 case POSTDEC:
1773 ((JCUnary) e).setTag(PREDEC);
1774 break;
1775 }
1776 genExpr(tree.expr, tree.expr.type).drop();
1777 }
1779 public void visitBreak(JCBreak tree) {
1780 Env<GenContext> targetEnv = unwind(tree.target, env);
1781 Assert.check(code.state.stacksize == 0);
1782 targetEnv.info.addExit(code.branch(goto_));
1783 endFinalizerGaps(env, targetEnv);
1784 }
1786 public void visitContinue(JCContinue tree) {
1787 Env<GenContext> targetEnv = unwind(tree.target, env);
1788 Assert.check(code.state.stacksize == 0);
1789 targetEnv.info.addCont(code.branch(goto_));
1790 endFinalizerGaps(env, targetEnv);
1791 }
1793 public void visitReturn(JCReturn tree) {
1794 int limit = code.nextreg;
1795 final Env<GenContext> targetEnv;
1797 /* Save and then restore the location of the return in case a finally
1798 * is expanded (with unwind()) in the middle of our bytecodes.
1799 */
1800 int tmpPos = code.pendingStatPos;
1801 if (tree.expr != null) {
1802 Item r = genExpr(tree.expr, pt).load();
1803 if (hasFinally(env.enclMethod, env)) {
1804 r = makeTemp(pt);
1805 r.store();
1806 }
1807 targetEnv = unwind(env.enclMethod, env);
1808 code.pendingStatPos = tmpPos;
1809 r.load();
1810 code.emitop0(ireturn + Code.truncate(Code.typecode(pt)));
1811 } else {
1812 targetEnv = unwind(env.enclMethod, env);
1813 code.pendingStatPos = tmpPos;
1814 code.emitop0(return_);
1815 }
1816 endFinalizerGaps(env, targetEnv);
1817 code.endScopes(limit);
1818 }
1820 public void visitThrow(JCThrow tree) {
1821 genExpr(tree.expr, tree.expr.type).load();
1822 code.emitop0(athrow);
1823 }
1825 /* ************************************************************************
1826 * Visitor methods for expressions
1827 *************************************************************************/
1829 public void visitApply(JCMethodInvocation tree) {
1830 setTypeAnnotationPositions(tree.pos);
1831 // Generate code for method.
1832 Item m = genExpr(tree.meth, methodType);
1833 // Generate code for all arguments, where the expected types are
1834 // the parameters of the method's external type (that is, any implicit
1835 // outer instance of a super(...) call appears as first parameter).
1836 MethodSymbol msym = (MethodSymbol)TreeInfo.symbol(tree.meth);
1837 genArgs(tree.args,
1838 msym.externalType(types).getParameterTypes());
1839 if (!msym.isDynamic()) {
1840 code.statBegin(tree.pos);
1841 }
1842 result = m.invoke();
1843 }
1845 public void visitConditional(JCConditional tree) {
1846 Chain thenExit = null;
1847 CondItem c = genCond(tree.cond, CRT_FLOW_CONTROLLER);
1848 Chain elseChain = c.jumpFalse();
1849 if (!c.isFalse()) {
1850 code.resolve(c.trueJumps);
1851 int startpc = genCrt ? code.curCP() : 0;
1852 genExpr(tree.truepart, pt).load();
1853 code.state.forceStackTop(tree.type);
1854 if (genCrt) code.crt.put(tree.truepart, CRT_FLOW_TARGET,
1855 startpc, code.curCP());
1856 thenExit = code.branch(goto_);
1857 }
1858 if (elseChain != null) {
1859 code.resolve(elseChain);
1860 int startpc = genCrt ? code.curCP() : 0;
1861 genExpr(tree.falsepart, pt).load();
1862 code.state.forceStackTop(tree.type);
1863 if (genCrt) code.crt.put(tree.falsepart, CRT_FLOW_TARGET,
1864 startpc, code.curCP());
1865 }
1866 code.resolve(thenExit);
1867 result = items.makeStackItem(pt);
1868 }
1870 private void setTypeAnnotationPositions(int treePos) {
1871 MethodSymbol meth = code.meth;
1872 boolean initOrClinit = code.meth.getKind() == javax.lang.model.element.ElementKind.CONSTRUCTOR
1873 || code.meth.getKind() == javax.lang.model.element.ElementKind.STATIC_INIT;
1875 for (Attribute.TypeCompound ta : meth.getRawTypeAttributes()) {
1876 if (ta.hasUnknownPosition())
1877 ta.tryFixPosition();
1879 if (ta.position.matchesPos(treePos))
1880 ta.position.updatePosOffset(code.cp);
1881 }
1883 if (!initOrClinit)
1884 return;
1886 for (Attribute.TypeCompound ta : meth.owner.getRawTypeAttributes()) {
1887 if (ta.hasUnknownPosition())
1888 ta.tryFixPosition();
1890 if (ta.position.matchesPos(treePos))
1891 ta.position.updatePosOffset(code.cp);
1892 }
1894 ClassSymbol clazz = meth.enclClass();
1895 for (Symbol s : new com.sun.tools.javac.model.FilteredMemberList(clazz.members())) {
1896 if (!s.getKind().isField())
1897 continue;
1899 for (Attribute.TypeCompound ta : s.getRawTypeAttributes()) {
1900 if (ta.hasUnknownPosition())
1901 ta.tryFixPosition();
1903 if (ta.position.matchesPos(treePos))
1904 ta.position.updatePosOffset(code.cp);
1905 }
1906 }
1907 }
1909 public void visitNewClass(JCNewClass tree) {
1910 // Enclosing instances or anonymous classes should have been eliminated
1911 // by now.
1912 Assert.check(tree.encl == null && tree.def == null);
1913 setTypeAnnotationPositions(tree.pos);
1915 code.emitop2(new_, makeRef(tree.pos(), tree.type));
1916 code.emitop0(dup);
1918 // Generate code for all arguments, where the expected types are
1919 // the parameters of the constructor's external type (that is,
1920 // any implicit outer instance appears as first parameter).
1921 genArgs(tree.args, tree.constructor.externalType(types).getParameterTypes());
1923 items.makeMemberItem(tree.constructor, true).invoke();
1924 result = items.makeStackItem(tree.type);
1925 }
1927 public void visitNewArray(JCNewArray tree) {
1928 setTypeAnnotationPositions(tree.pos);
1930 if (tree.elems != null) {
1931 Type elemtype = types.elemtype(tree.type);
1932 loadIntConst(tree.elems.length());
1933 Item arr = makeNewArray(tree.pos(), tree.type, 1);
1934 int i = 0;
1935 for (List<JCExpression> l = tree.elems; l.nonEmpty(); l = l.tail) {
1936 arr.duplicate();
1937 loadIntConst(i);
1938 i++;
1939 genExpr(l.head, elemtype).load();
1940 items.makeIndexedItem(elemtype).store();
1941 }
1942 result = arr;
1943 } else {
1944 for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) {
1945 genExpr(l.head, syms.intType).load();
1946 }
1947 result = makeNewArray(tree.pos(), tree.type, tree.dims.length());
1948 }
1949 }
1950 //where
1951 /** Generate code to create an array with given element type and number
1952 * of dimensions.
1953 */
1954 Item makeNewArray(DiagnosticPosition pos, Type type, int ndims) {
1955 Type elemtype = types.elemtype(type);
1956 if (types.dimensions(type) > ClassFile.MAX_DIMENSIONS) {
1957 log.error(pos, "limit.dimensions");
1958 nerrs++;
1959 }
1960 int elemcode = Code.arraycode(elemtype);
1961 if (elemcode == 0 || (elemcode == 1 && ndims == 1)) {
1962 code.emitAnewarray(makeRef(pos, elemtype), type);
1963 } else if (elemcode == 1) {
1964 code.emitMultianewarray(ndims, makeRef(pos, type), type);
1965 } else {
1966 code.emitNewarray(elemcode, type);
1967 }
1968 return items.makeStackItem(type);
1969 }
1971 public void visitParens(JCParens tree) {
1972 result = genExpr(tree.expr, tree.expr.type);
1973 }
1975 public void visitAssign(JCAssign tree) {
1976 Item l = genExpr(tree.lhs, tree.lhs.type);
1977 genExpr(tree.rhs, tree.lhs.type).load();
1978 result = items.makeAssignItem(l);
1979 }
1981 public void visitAssignop(JCAssignOp tree) {
1982 OperatorSymbol operator = (OperatorSymbol) tree.operator;
1983 Item l;
1984 if (operator.opcode == string_add) {
1985 // Generate code to make a string buffer
1986 makeStringBuffer(tree.pos());
1988 // Generate code for first string, possibly save one
1989 // copy under buffer
1990 l = genExpr(tree.lhs, tree.lhs.type);
1991 if (l.width() > 0) {
1992 code.emitop0(dup_x1 + 3 * (l.width() - 1));
1993 }
1995 // Load first string and append to buffer.
1996 l.load();
1997 appendString(tree.lhs);
1999 // Append all other strings to buffer.
2000 appendStrings(tree.rhs);
2002 // Convert buffer to string.
2003 bufferToString(tree.pos());
2004 } else {
2005 // Generate code for first expression
2006 l = genExpr(tree.lhs, tree.lhs.type);
2008 // If we have an increment of -32768 to +32767 of a local
2009 // int variable we can use an incr instruction instead of
2010 // proceeding further.
2011 if ((tree.hasTag(PLUS_ASG) || tree.hasTag(MINUS_ASG)) &&
2012 l instanceof LocalItem &&
2013 tree.lhs.type.getTag().isSubRangeOf(INT) &&
2014 tree.rhs.type.getTag().isSubRangeOf(INT) &&
2015 tree.rhs.type.constValue() != null) {
2016 int ival = ((Number) tree.rhs.type.constValue()).intValue();
2017 if (tree.hasTag(MINUS_ASG)) ival = -ival;
2018 ((LocalItem)l).incr(ival);
2019 result = l;
2020 return;
2021 }
2022 // Otherwise, duplicate expression, load one copy
2023 // and complete binary operation.
2024 l.duplicate();
2025 l.coerce(operator.type.getParameterTypes().head).load();
2026 completeBinop(tree.lhs, tree.rhs, operator).coerce(tree.lhs.type);
2027 }
2028 result = items.makeAssignItem(l);
2029 }
2031 public void visitUnary(JCUnary tree) {
2032 OperatorSymbol operator = (OperatorSymbol)tree.operator;
2033 if (tree.hasTag(NOT)) {
2034 CondItem od = genCond(tree.arg, false);
2035 result = od.negate();
2036 } else {
2037 Item od = genExpr(tree.arg, operator.type.getParameterTypes().head);
2038 switch (tree.getTag()) {
2039 case POS:
2040 result = od.load();
2041 break;
2042 case NEG:
2043 result = od.load();
2044 code.emitop0(operator.opcode);
2045 break;
2046 case COMPL:
2047 result = od.load();
2048 emitMinusOne(od.typecode);
2049 code.emitop0(operator.opcode);
2050 break;
2051 case PREINC: case PREDEC:
2052 od.duplicate();
2053 if (od instanceof LocalItem &&
2054 (operator.opcode == iadd || operator.opcode == isub)) {
2055 ((LocalItem)od).incr(tree.hasTag(PREINC) ? 1 : -1);
2056 result = od;
2057 } else {
2058 od.load();
2059 code.emitop0(one(od.typecode));
2060 code.emitop0(operator.opcode);
2061 // Perform narrowing primitive conversion if byte,
2062 // char, or short. Fix for 4304655.
2063 if (od.typecode != INTcode &&
2064 Code.truncate(od.typecode) == INTcode)
2065 code.emitop0(int2byte + od.typecode - BYTEcode);
2066 result = items.makeAssignItem(od);
2067 }
2068 break;
2069 case POSTINC: case POSTDEC:
2070 od.duplicate();
2071 if (od instanceof LocalItem &&
2072 (operator.opcode == iadd || operator.opcode == isub)) {
2073 Item res = od.load();
2074 ((LocalItem)od).incr(tree.hasTag(POSTINC) ? 1 : -1);
2075 result = res;
2076 } else {
2077 Item res = od.load();
2078 od.stash(od.typecode);
2079 code.emitop0(one(od.typecode));
2080 code.emitop0(operator.opcode);
2081 // Perform narrowing primitive conversion if byte,
2082 // char, or short. Fix for 4304655.
2083 if (od.typecode != INTcode &&
2084 Code.truncate(od.typecode) == INTcode)
2085 code.emitop0(int2byte + od.typecode - BYTEcode);
2086 od.store();
2087 result = res;
2088 }
2089 break;
2090 case NULLCHK:
2091 result = od.load();
2092 code.emitop0(dup);
2093 genNullCheck(tree.pos());
2094 break;
2095 default:
2096 Assert.error();
2097 }
2098 }
2099 }
2101 /** Generate a null check from the object value at stack top. */
2102 private void genNullCheck(DiagnosticPosition pos) {
2103 callMethod(pos, syms.objectType, names.getClass,
2104 List.<Type>nil(), false);
2105 code.emitop0(pop);
2106 }
2108 public void visitBinary(JCBinary tree) {
2109 OperatorSymbol operator = (OperatorSymbol)tree.operator;
2110 if (operator.opcode == string_add) {
2111 // Create a string buffer.
2112 makeStringBuffer(tree.pos());
2113 // Append all strings to buffer.
2114 appendStrings(tree);
2115 // Convert buffer to string.
2116 bufferToString(tree.pos());
2117 result = items.makeStackItem(syms.stringType);
2118 } else if (tree.hasTag(AND)) {
2119 CondItem lcond = genCond(tree.lhs, CRT_FLOW_CONTROLLER);
2120 if (!lcond.isFalse()) {
2121 Chain falseJumps = lcond.jumpFalse();
2122 code.resolve(lcond.trueJumps);
2123 CondItem rcond = genCond(tree.rhs, CRT_FLOW_TARGET);
2124 result = items.
2125 makeCondItem(rcond.opcode,
2126 rcond.trueJumps,
2127 Code.mergeChains(falseJumps,
2128 rcond.falseJumps));
2129 } else {
2130 result = lcond;
2131 }
2132 } else if (tree.hasTag(OR)) {
2133 CondItem lcond = genCond(tree.lhs, CRT_FLOW_CONTROLLER);
2134 if (!lcond.isTrue()) {
2135 Chain trueJumps = lcond.jumpTrue();
2136 code.resolve(lcond.falseJumps);
2137 CondItem rcond = genCond(tree.rhs, CRT_FLOW_TARGET);
2138 result = items.
2139 makeCondItem(rcond.opcode,
2140 Code.mergeChains(trueJumps, rcond.trueJumps),
2141 rcond.falseJumps);
2142 } else {
2143 result = lcond;
2144 }
2145 } else {
2146 Item od = genExpr(tree.lhs, operator.type.getParameterTypes().head);
2147 od.load();
2148 result = completeBinop(tree.lhs, tree.rhs, operator);
2149 }
2150 }
2151 //where
2152 /** Make a new string buffer.
2153 */
2154 void makeStringBuffer(DiagnosticPosition pos) {
2155 code.emitop2(new_, makeRef(pos, stringBufferType));
2156 code.emitop0(dup);
2157 callMethod(
2158 pos, stringBufferType, names.init, List.<Type>nil(), false);
2159 }
2161 /** Append value (on tos) to string buffer (on tos - 1).
2162 */
2163 void appendString(JCTree tree) {
2164 Type t = tree.type.baseType();
2165 if (!t.isPrimitive() && t.tsym != syms.stringType.tsym) {
2166 t = syms.objectType;
2167 }
2168 items.makeMemberItem(getStringBufferAppend(tree, t), false).invoke();
2169 }
2170 Symbol getStringBufferAppend(JCTree tree, Type t) {
2171 Assert.checkNull(t.constValue());
2172 Symbol method = stringBufferAppend.get(t);
2173 if (method == null) {
2174 method = rs.resolveInternalMethod(tree.pos(),
2175 attrEnv,
2176 stringBufferType,
2177 names.append,
2178 List.of(t),
2179 null);
2180 stringBufferAppend.put(t, method);
2181 }
2182 return method;
2183 }
2185 /** Add all strings in tree to string buffer.
2186 */
2187 void appendStrings(JCTree tree) {
2188 tree = TreeInfo.skipParens(tree);
2189 if (tree.hasTag(PLUS) && tree.type.constValue() == null) {
2190 JCBinary op = (JCBinary) tree;
2191 if (op.operator.kind == MTH &&
2192 ((OperatorSymbol) op.operator).opcode == string_add) {
2193 appendStrings(op.lhs);
2194 appendStrings(op.rhs);
2195 return;
2196 }
2197 }
2198 genExpr(tree, tree.type).load();
2199 appendString(tree);
2200 }
2202 /** Convert string buffer on tos to string.
2203 */
2204 void bufferToString(DiagnosticPosition pos) {
2205 callMethod(
2206 pos,
2207 stringBufferType,
2208 names.toString,
2209 List.<Type>nil(),
2210 false);
2211 }
2213 /** Complete generating code for operation, with left operand
2214 * already on stack.
2215 * @param lhs The tree representing the left operand.
2216 * @param rhs The tree representing the right operand.
2217 * @param operator The operator symbol.
2218 */
2219 Item completeBinop(JCTree lhs, JCTree rhs, OperatorSymbol operator) {
2220 MethodType optype = (MethodType)operator.type;
2221 int opcode = operator.opcode;
2222 if (opcode >= if_icmpeq && opcode <= if_icmple &&
2223 rhs.type.constValue() instanceof Number &&
2224 ((Number) rhs.type.constValue()).intValue() == 0) {
2225 opcode = opcode + (ifeq - if_icmpeq);
2226 } else if (opcode >= if_acmpeq && opcode <= if_acmpne &&
2227 TreeInfo.isNull(rhs)) {
2228 opcode = opcode + (if_acmp_null - if_acmpeq);
2229 } else {
2230 // The expected type of the right operand is
2231 // the second parameter type of the operator, except for
2232 // shifts with long shiftcount, where we convert the opcode
2233 // to a short shift and the expected type to int.
2234 Type rtype = operator.erasure(types).getParameterTypes().tail.head;
2235 if (opcode >= ishll && opcode <= lushrl) {
2236 opcode = opcode + (ishl - ishll);
2237 rtype = syms.intType;
2238 }
2239 // Generate code for right operand and load.
2240 genExpr(rhs, rtype).load();
2241 // If there are two consecutive opcode instructions,
2242 // emit the first now.
2243 if (opcode >= (1 << preShift)) {
2244 code.emitop0(opcode >> preShift);
2245 opcode = opcode & 0xFF;
2246 }
2247 }
2248 if (opcode >= ifeq && opcode <= if_acmpne ||
2249 opcode == if_acmp_null || opcode == if_acmp_nonnull) {
2250 return items.makeCondItem(opcode);
2251 } else {
2252 code.emitop0(opcode);
2253 return items.makeStackItem(optype.restype);
2254 }
2255 }
2257 public void visitTypeCast(JCTypeCast tree) {
2258 setTypeAnnotationPositions(tree.pos);
2259 result = genExpr(tree.expr, tree.clazz.type).load();
2260 // Additional code is only needed if we cast to a reference type
2261 // which is not statically a supertype of the expression's type.
2262 // For basic types, the coerce(...) in genExpr(...) will do
2263 // the conversion.
2264 if (!tree.clazz.type.isPrimitive() &&
2265 types.asSuper(tree.expr.type, tree.clazz.type.tsym) == null) {
2266 code.emitop2(checkcast, makeRef(tree.pos(), tree.clazz.type));
2267 }
2268 }
2270 public void visitWildcard(JCWildcard tree) {
2271 throw new AssertionError(this.getClass().getName());
2272 }
2274 public void visitTypeTest(JCInstanceOf tree) {
2275 setTypeAnnotationPositions(tree.pos);
2276 genExpr(tree.expr, tree.expr.type).load();
2277 code.emitop2(instanceof_, makeRef(tree.pos(), tree.clazz.type));
2278 result = items.makeStackItem(syms.booleanType);
2279 }
2281 public void visitIndexed(JCArrayAccess tree) {
2282 genExpr(tree.indexed, tree.indexed.type).load();
2283 genExpr(tree.index, syms.intType).load();
2284 result = items.makeIndexedItem(tree.type);
2285 }
2287 public void visitIdent(JCIdent tree) {
2288 Symbol sym = tree.sym;
2289 if (tree.name == names._this || tree.name == names._super) {
2290 Item res = tree.name == names._this
2291 ? items.makeThisItem()
2292 : items.makeSuperItem();
2293 if (sym.kind == MTH) {
2294 // Generate code to address the constructor.
2295 res.load();
2296 res = items.makeMemberItem(sym, true);
2297 }
2298 result = res;
2299 } else if (sym.kind == VAR && sym.owner.kind == MTH) {
2300 result = items.makeLocalItem((VarSymbol)sym);
2301 } else if (isInvokeDynamic(sym)) {
2302 result = items.makeDynamicItem(sym);
2303 } else if ((sym.flags() & STATIC) != 0) {
2304 if (!isAccessSuper(env.enclMethod))
2305 sym = binaryQualifier(sym, env.enclClass.type);
2306 result = items.makeStaticItem(sym);
2307 } else {
2308 items.makeThisItem().load();
2309 sym = binaryQualifier(sym, env.enclClass.type);
2310 result = items.makeMemberItem(sym, (sym.flags() & PRIVATE) != 0);
2311 }
2312 }
2314 public void visitSelect(JCFieldAccess tree) {
2315 Symbol sym = tree.sym;
2317 if (tree.name == names._class) {
2318 Assert.check(target.hasClassLiterals());
2319 code.emitLdc(makeRef(tree.pos(), tree.selected.type));
2320 result = items.makeStackItem(pt);
2321 return;
2322 }
2324 Symbol ssym = TreeInfo.symbol(tree.selected);
2326 // Are we selecting via super?
2327 boolean selectSuper =
2328 ssym != null && (ssym.kind == TYP || ssym.name == names._super);
2330 // Are we accessing a member of the superclass in an access method
2331 // resulting from a qualified super?
2332 boolean accessSuper = isAccessSuper(env.enclMethod);
2334 Item base = (selectSuper)
2335 ? items.makeSuperItem()
2336 : genExpr(tree.selected, tree.selected.type);
2338 if (sym.kind == VAR && ((VarSymbol) sym).getConstValue() != null) {
2339 // We are seeing a variable that is constant but its selecting
2340 // expression is not.
2341 if ((sym.flags() & STATIC) != 0) {
2342 if (!selectSuper && (ssym == null || ssym.kind != TYP))
2343 base = base.load();
2344 base.drop();
2345 } else {
2346 base.load();
2347 genNullCheck(tree.selected.pos());
2348 }
2349 result = items.
2350 makeImmediateItem(sym.type, ((VarSymbol) sym).getConstValue());
2351 } else {
2352 if (isInvokeDynamic(sym)) {
2353 result = items.makeDynamicItem(sym);
2354 return;
2355 } else {
2356 sym = binaryQualifier(sym, tree.selected.type);
2357 }
2358 if ((sym.flags() & STATIC) != 0) {
2359 if (!selectSuper && (ssym == null || ssym.kind != TYP))
2360 base = base.load();
2361 base.drop();
2362 result = items.makeStaticItem(sym);
2363 } else {
2364 base.load();
2365 if (sym == syms.lengthVar) {
2366 code.emitop0(arraylength);
2367 result = items.makeStackItem(syms.intType);
2368 } else {
2369 result = items.
2370 makeMemberItem(sym,
2371 (sym.flags() & PRIVATE) != 0 ||
2372 selectSuper || accessSuper);
2373 }
2374 }
2375 }
2376 }
2378 public boolean isInvokeDynamic(Symbol sym) {
2379 return sym.kind == MTH && ((MethodSymbol)sym).isDynamic();
2380 }
2382 public void visitLiteral(JCLiteral tree) {
2383 if (tree.type.hasTag(BOT)) {
2384 code.emitop0(aconst_null);
2385 if (types.dimensions(pt) > 1) {
2386 code.emitop2(checkcast, makeRef(tree.pos(), pt));
2387 result = items.makeStackItem(pt);
2388 } else {
2389 result = items.makeStackItem(tree.type);
2390 }
2391 }
2392 else
2393 result = items.makeImmediateItem(tree.type, tree.value);
2394 }
2396 public void visitLetExpr(LetExpr tree) {
2397 int limit = code.nextreg;
2398 genStats(tree.defs, env);
2399 result = genExpr(tree.expr, tree.expr.type).load();
2400 code.endScopes(limit);
2401 }
2403 private void generateReferencesToPrunedTree(ClassSymbol classSymbol, Pool pool) {
2404 List<JCTree> prunedInfo = lower.prunedTree.get(classSymbol);
2405 if (prunedInfo != null) {
2406 for (JCTree prunedTree: prunedInfo) {
2407 prunedTree.accept(classReferenceVisitor);
2408 }
2409 }
2410 }
2412 /* ************************************************************************
2413 * main method
2414 *************************************************************************/
2416 /** Generate code for a class definition.
2417 * @param env The attribution environment that belongs to the
2418 * outermost class containing this class definition.
2419 * We need this for resolving some additional symbols.
2420 * @param cdef The tree representing the class definition.
2421 * @return True if code is generated with no errors.
2422 */
2423 public boolean genClass(Env<AttrContext> env, JCClassDecl cdef) {
2424 try {
2425 attrEnv = env;
2426 ClassSymbol c = cdef.sym;
2427 this.toplevel = env.toplevel;
2428 this.endPosTable = toplevel.endPositions;
2429 // If this is a class definition requiring Miranda methods,
2430 // add them.
2431 if (generateIproxies &&
2432 (c.flags() & (INTERFACE|ABSTRACT)) == ABSTRACT
2433 && !allowGenerics // no Miranda methods available with generics
2434 )
2435 implementInterfaceMethods(c);
2436 c.pool = pool;
2437 pool.reset();
2438 /* method normalizeDefs() can add references to external classes into the constant pool
2439 * so it should be called after pool.reset()
2440 */
2441 cdef.defs = normalizeDefs(cdef.defs, c);
2442 generateReferencesToPrunedTree(c, pool);
2443 Env<GenContext> localEnv =
2444 new Env<GenContext>(cdef, new GenContext());
2445 localEnv.toplevel = env.toplevel;
2446 localEnv.enclClass = cdef;
2448 for (List<JCTree> l = cdef.defs; l.nonEmpty(); l = l.tail) {
2449 genDef(l.head, localEnv);
2450 }
2451 if (pool.numEntries() > Pool.MAX_ENTRIES) {
2452 log.error(cdef.pos(), "limit.pool");
2453 nerrs++;
2454 }
2455 if (nerrs != 0) {
2456 // if errors, discard code
2457 for (List<JCTree> l = cdef.defs; l.nonEmpty(); l = l.tail) {
2458 if (l.head.hasTag(METHODDEF))
2459 ((JCMethodDecl) l.head).sym.code = null;
2460 }
2461 }
2462 cdef.defs = List.nil(); // discard trees
2463 return nerrs == 0;
2464 } finally {
2465 // note: this method does NOT support recursion.
2466 attrEnv = null;
2467 this.env = null;
2468 toplevel = null;
2469 endPosTable = null;
2470 nerrs = 0;
2471 }
2472 }
2474 /* ************************************************************************
2475 * Auxiliary classes
2476 *************************************************************************/
2478 /** An abstract class for finalizer generation.
2479 */
2480 abstract class GenFinalizer {
2481 /** Generate code to clean up when unwinding. */
2482 abstract void gen();
2484 /** Generate code to clean up at last. */
2485 abstract void genLast();
2487 /** Does this finalizer have some nontrivial cleanup to perform? */
2488 boolean hasFinalizer() { return true; }
2489 }
2491 /** code generation contexts,
2492 * to be used as type parameter for environments.
2493 */
2494 static class GenContext {
2496 /** A chain for all unresolved jumps that exit the current environment.
2497 */
2498 Chain exit = null;
2500 /** A chain for all unresolved jumps that continue in the
2501 * current environment.
2502 */
2503 Chain cont = null;
2505 /** A closure that generates the finalizer of the current environment.
2506 * Only set for Synchronized and Try contexts.
2507 */
2508 GenFinalizer finalize = null;
2510 /** Is this a switch statement? If so, allocate registers
2511 * even when the variable declaration is unreachable.
2512 */
2513 boolean isSwitch = false;
2515 /** A list buffer containing all gaps in the finalizer range,
2516 * where a catch all exception should not apply.
2517 */
2518 ListBuffer<Integer> gaps = null;
2520 /** Add given chain to exit chain.
2521 */
2522 void addExit(Chain c) {
2523 exit = Code.mergeChains(c, exit);
2524 }
2526 /** Add given chain to cont chain.
2527 */
2528 void addCont(Chain c) {
2529 cont = Code.mergeChains(c, cont);
2530 }
2531 }
2533 }
