1 /*
2 * Copyright (c) 1999, 2024, 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
80 private final StringConcat concat;
81
82 /** Format of stackmap tables to be generated. */
83 private final Code.StackMapFormat stackMap;
84
85 /** A type that serves as the expected type for all method expressions.
86 */
87 private final Type methodType;
88
89 public static Gen instance(Context context) {
90 Gen instance = context.get(genKey);
91 if (instance == null)
92 instance = new Gen(context);
93 return instance;
94 }
95
96 /** Constant pool writer, set by genClass.
97 */
98 final PoolWriter poolWriter;
99
100 @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
114 methodType = new MethodType(null, null, null, syms.methodClass);
115 accessDollar = "access" + target.syntheticNameChar();
116 lower = Lower.instance(context);
117
118 Options options = Options.instance(context);
119 lineDebugInfo =
120 options.isUnset(G_CUSTOM) ||
121 options.isSet(G_CUSTOM, "lines");
122 varDebugInfo =
123 options.isUnset(G_CUSTOM)
124 ? options.isSet(G)
125 : options.isSet(G_CUSTOM, "vars");
126 genCrt = options.isSet(XJCOV);
127 debugCode = options.isSet("debug.code");
128 disableVirtualizedPrivateInvoke = options.isSet("disableVirtualizedPrivateInvoke");
129 poolWriter = new PoolWriter(types, names);
130
131 // ignore cldc because we cannot have both stackmap formats
132 this.stackMap = StackMapFormat.JSR202;
133 annotate = Annotate.instance(context);
134 qualifiedSymbolCache = new HashMap<>();
135 }
136
137 /** Switches
138 */
139 private final boolean lineDebugInfo;
140 private final boolean varDebugInfo;
141 private final boolean genCrt;
142 private final boolean debugCode;
143 private boolean disableVirtualizedPrivateInvoke;
144
145 /** Code buffer, set by genMethod.
146 */
147 private Code code;
148
149 /** Items structure, set by genMethod.
150 */
151 private Items items;
152
153 /** Environment for symbol lookup, set by genClass
154 */
155 private Env<AttrContext> attrEnv;
156
157 /** The top level tree.
158 */
159 private JCCompilationUnit toplevel;
160
161 /** The number of code-gen errors in this class.
162 */
163 private int nerrs = 0;
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 defs The list of class member declarations.
423 * @param c The enclosing class.
424 */
425 List<JCTree> normalizeDefs(List<JCTree> defs, ClassSymbol c) {
426 ListBuffer<JCStatement> initCode = new ListBuffer<>();
427 ListBuffer<Attribute.TypeCompound> initTAs = new ListBuffer<>();
428 ListBuffer<JCStatement> clinitCode = new ListBuffer<>();
429 ListBuffer<Attribute.TypeCompound> clinitTAs = new ListBuffer<>();
430 ListBuffer<JCTree> methodDefs = new ListBuffer<>();
431 // Sort definitions into three listbuffers:
432 // - initCode for instance initializers
433 // - clinitCode for class initializers
434 // - methodDefs for method definitions
435 for (List<JCTree> l = defs; l.nonEmpty(); l = l.tail) {
436 JCTree def = l.head;
437 switch (def.getTag()) {
438 case BLOCK:
439 JCBlock block = (JCBlock)def;
440 if ((block.flags & STATIC) != 0)
441 clinitCode.append(block);
442 else if ((block.flags & SYNTHETIC) == 0)
443 initCode.append(block);
444 break;
445 case METHODDEF:
446 methodDefs.append(def);
447 break;
448 case VARDEF:
449 JCVariableDecl vdef = (JCVariableDecl) def;
450 VarSymbol sym = vdef.sym;
451 checkDimension(vdef.pos(), sym.type);
452 if (vdef.init != null) {
453 if ((sym.flags() & STATIC) == 0) {
454 // Always initialize instance variables.
455 JCStatement init = make.at(vdef.pos()).
456 Assignment(sym, vdef.init);
457 initCode.append(init);
458 endPosTable.replaceTree(vdef, init);
459 initTAs.addAll(getAndRemoveNonFieldTAs(sym));
460 } else if (sym.getConstValue() == null) {
461 // Initialize class (static) variables only if
462 // they are not compile-time constants.
463 JCStatement init = make.at(vdef.pos).
464 Assignment(sym, vdef.init);
465 clinitCode.append(init);
466 endPosTable.replaceTree(vdef, init);
467 clinitTAs.addAll(getAndRemoveNonFieldTAs(sym));
468 } else {
469 checkStringConstant(vdef.init.pos(), sym.getConstValue());
470 /* if the init contains a reference to an external class, add it to the
471 * constant's pool
472 */
473 vdef.init.accept(classReferenceVisitor);
474 }
475 }
476 break;
477 default:
478 Assert.error();
479 }
480 }
481 // Insert any instance initializers into all constructors.
482 if (initCode.length() != 0) {
483 List<JCStatement> inits = initCode.toList();
484 initTAs.addAll(c.getInitTypeAttributes());
485 List<Attribute.TypeCompound> initTAlist = initTAs.toList();
486 for (JCTree t : methodDefs) {
487 normalizeMethod((JCMethodDecl)t, inits, initTAlist);
488 }
489 }
490 // If there are class initializers, create a <clinit> method
491 // that contains them as its body.
492 if (clinitCode.length() != 0) {
493 MethodSymbol clinit = new MethodSymbol(
494 STATIC | (c.flags() & STRICTFP),
495 names.clinit,
496 new MethodType(
497 List.nil(), syms.voidType,
498 List.nil(), syms.methodClass),
499 c);
500 c.members().enter(clinit);
501 List<JCStatement> clinitStats = clinitCode.toList();
502 JCBlock block = make.at(clinitStats.head.pos()).Block(0, clinitStats);
503 block.endpos = TreeInfo.endPos(clinitStats.last());
504 methodDefs.append(make.MethodDef(clinit, block));
505
506 if (!clinitTAs.isEmpty())
507 clinit.appendUniqueTypeAttributes(clinitTAs.toList());
530
531 /** Check a constant value and report if it is a string that is
532 * too large.
533 */
534 private void checkStringConstant(DiagnosticPosition pos, Object constValue) {
535 if (nerrs != 0 || // only complain about a long string once
536 constValue == null ||
537 !(constValue instanceof String str) ||
538 str.length() < PoolWriter.MAX_STRING_LENGTH)
539 return;
540 log.error(pos, Errors.LimitString);
541 nerrs++;
542 }
543
544 /** Insert instance initializer code into constructors prior to the super() call.
545 * @param md The tree potentially representing a
546 * constructor's definition.
547 * @param initCode The list of instance initializer statements.
548 * @param initTAs Type annotations from the initializer expression.
549 */
550 void normalizeMethod(JCMethodDecl md, List<JCStatement> initCode, List<TypeCompound> initTAs) {
551 if (TreeInfo.isConstructor(md) && TreeInfo.hasConstructorCall(md, names._super)) {
552 // We are seeing a constructor that has a super() call.
553 // Find the super() invocation and append the given initializer code.
554 TreeInfo.mapSuperCalls(md.body, supercall -> make.Block(0, initCode.prepend(supercall)));
555
556 if (md.body.endpos == Position.NOPOS)
557 md.body.endpos = TreeInfo.endPos(md.body.stats.last());
558
559 md.sym.appendUniqueTypeAttributes(initTAs);
560 }
561 }
562
563 /* ************************************************************************
564 * Traversal methods
565 *************************************************************************/
566
567 /** Visitor argument: The current environment.
568 */
569 Env<GenContext> env;
570
571 /** Visitor argument: The expected type (prototype).
572 */
573 Type pt;
574
575 /** Visitor result: The item representing the computed value.
576 */
577 Item result;
578
579 /** Visitor method: generate code for a definition, catching and reporting
580 * any completion failures.
581 * @param tree The definition to be visited.
582 * @param env The environment current at the definition.
927 // Count up extra parameters
928 if (meth.isConstructor()) {
929 extras++;
930 if (meth.enclClass().isInner() &&
931 !meth.enclClass().isStatic()) {
932 extras++;
933 }
934 } else if ((tree.mods.flags & STATIC) == 0) {
935 extras++;
936 }
937 // System.err.println("Generating " + meth + " in " + meth.owner); //DEBUG
938 if (Code.width(types.erasure(env.enclMethod.sym.type).getParameterTypes()) + extras >
939 ClassFile.MAX_PARAMETERS) {
940 log.error(tree.pos(), Errors.LimitParameters);
941 nerrs++;
942 }
943
944 else if (tree.body != null) {
945 // Create a new code structure and initialize it.
946 int startpcCrt = initCode(tree, env, fatcode);
947
948 try {
949 genStat(tree.body, env);
950 } catch (CodeSizeOverflow e) {
951 // Failed due to code limit, try again with jsr/ret
952 startpcCrt = initCode(tree, env, fatcode);
953 genStat(tree.body, env);
954 }
955
956 if (code.state.stacksize != 0) {
957 log.error(tree.body.pos(), Errors.StackSimError(tree.sym));
958 throw new AssertionError();
959 }
960
961 // If last statement could complete normally, insert a
962 // return at the end.
963 if (code.isAlive()) {
964 code.statBegin(TreeInfo.endPos(tree.body));
965 if (env.enclMethod == null ||
966 env.enclMethod.sym.type.getReturnType().hasTag(VOID)) {
967 code.emitop0(return_);
968 } else {
969 // sometime dead code seems alive (4415991);
970 // generate a small loop instead
971 int startpc = code.entryPoint();
972 CondItem c = items.makeCondItem(goto_);
973 code.resolve(c.jumpTrue(), startpc);
1002
1003 // Fill in type annotation positions for exception parameters
1004 code.fillExceptionParameterPositions();
1005 }
1006 }
1007
1008 private int initCode(JCMethodDecl tree, Env<GenContext> env, boolean fatcode) {
1009 MethodSymbol meth = tree.sym;
1010
1011 // Create a new code structure.
1012 meth.code = code = new Code(meth,
1013 fatcode,
1014 lineDebugInfo ? toplevel.lineMap : null,
1015 varDebugInfo,
1016 stackMap,
1017 debugCode,
1018 genCrt ? new CRTable(tree, env.toplevel.endPositions)
1019 : null,
1020 syms,
1021 types,
1022 poolWriter);
1023 items = new Items(poolWriter, code, syms, types);
1024 if (code.debugCode) {
1025 System.err.println(meth + " for body " + tree);
1026 }
1027
1028 // If method is not static, create a new local variable address
1029 // for `this'.
1030 if ((tree.mods.flags & STATIC) == 0) {
1031 Type selfType = meth.owner.type;
1032 if (meth.isConstructor() && selfType != syms.objectType)
1033 selfType = UninitializedType.uninitializedThis(selfType);
1034 code.setDefined(
1035 code.newLocal(
1036 new VarSymbol(FINAL, names._this, selfType, meth.owner)));
1037 }
1038
1039 // Mark all parameters as defined from the beginning of
1040 // the method.
1041 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
1042 checkDimension(l.head.pos(), l.head.sym.type);
1138 public void visitForLoop(JCForLoop tree) {
1139 int limit = code.nextreg;
1140 genStats(tree.init, env);
1141 genLoop(tree, tree.body, tree.cond, tree.step, true);
1142 code.endScopes(limit);
1143 }
1144 //where
1145 /** Generate code for a loop.
1146 * @param loop The tree representing the loop.
1147 * @param body The loop's body.
1148 * @param cond The loop's controlling condition.
1149 * @param step "Step" statements to be inserted at end of
1150 * each iteration.
1151 * @param testFirst True if the loop test belongs before the body.
1152 */
1153 private void genLoop(JCStatement loop,
1154 JCStatement body,
1155 JCExpression cond,
1156 List<JCExpressionStatement> step,
1157 boolean testFirst) {
1158 Env<GenContext> loopEnv = env.dup(loop, new GenContext());
1159 int startpc = code.entryPoint();
1160 if (testFirst) { //while or for loop
1161 CondItem c;
1162 if (cond != null) {
1163 code.statBegin(cond.pos);
1164 Assert.check(code.isStatementStart());
1165 c = genCond(TreeInfo.skipParens(cond), CRT_FLOW_CONTROLLER);
1166 } else {
1167 c = items.makeCondItem(goto_);
1168 }
1169 Chain loopDone = c.jumpFalse();
1170 code.resolve(c.trueJumps);
1171 Assert.check(code.isStatementStart());
1172 genStat(body, loopEnv, CRT_STATEMENT | CRT_FLOW_TARGET);
1173 code.resolve(loopEnv.info.cont);
1174 genStats(step, loopEnv);
1175 code.resolve(code.branch(goto_), startpc);
1176 code.resolve(loopDone);
1177 } else {
1204 }
1205
1206 public void visitLabelled(JCLabeledStatement tree) {
1207 Env<GenContext> localEnv = env.dup(tree, new GenContext());
1208 genStat(tree.body, localEnv, CRT_STATEMENT);
1209 Chain exit = localEnv.info.exit;
1210 if (exit != null) {
1211 code.resolve(exit);
1212 exit.state.defined.excludeFrom(code.nextreg);
1213 }
1214 }
1215
1216 public void visitSwitch(JCSwitch tree) {
1217 handleSwitch(tree, tree.selector, tree.cases, tree.patternSwitch);
1218 }
1219
1220 @Override
1221 public void visitSwitchExpression(JCSwitchExpression tree) {
1222 code.resolvePending();
1223 boolean prevInCondSwitchExpression = inCondSwitchExpression;
1224 try {
1225 inCondSwitchExpression = false;
1226 doHandleSwitchExpression(tree);
1227 } finally {
1228 inCondSwitchExpression = prevInCondSwitchExpression;
1229 }
1230 result = items.makeStackItem(pt);
1231 }
1232
1233 private void doHandleSwitchExpression(JCSwitchExpression tree) {
1234 List<LocalItem> prevStackBeforeSwitchExpression = stackBeforeSwitchExpression;
1235 LocalItem prevSwitchResult = switchResult;
1236 int limit = code.nextreg;
1237 try {
1238 stackBeforeSwitchExpression = List.nil();
1239 switchResult = null;
1240 if (hasTry(tree)) {
1241 //if the switch expression contains try-catch, the catch handlers need to have
1242 //an empty stack. So stash whole stack to local variables, and restore it before
1243 //breaks:
1244 while (code.state.stacksize > 0) {
1245 Type type = code.state.peek();
1246 Name varName = names.fromString(target.syntheticNameChar() +
1247 "stack" +
1248 target.syntheticNameChar() +
1284 hasTry = true;
1285 }
1286
1287 @Override
1288 public void visitClassDef(JCClassDecl tree) {
1289 }
1290
1291 @Override
1292 public void visitLambda(JCLambda tree) {
1293 }
1294 };
1295
1296 HasTryScanner hasTryScanner = new HasTryScanner();
1297
1298 hasTryScanner.scan(tree);
1299 return hasTryScanner.hasTry;
1300 }
1301
1302 private void handleSwitch(JCTree swtch, JCExpression selector, List<JCCase> cases,
1303 boolean patternSwitch) {
1304 int limit = code.nextreg;
1305 Assert.check(!selector.type.hasTag(CLASS));
1306 int switchStart = patternSwitch ? code.entryPoint() : -1;
1307 int startpcCrt = genCrt ? code.curCP() : 0;
1308 Assert.check(code.isStatementStart());
1309 Item sel = genExpr(selector, syms.intType);
1310 if (cases.isEmpty()) {
1311 // We are seeing: switch <sel> {}
1312 sel.load().drop();
1313 if (genCrt)
1314 code.crt.put(TreeInfo.skipParens(selector),
1315 CRT_FLOW_CONTROLLER, startpcCrt, code.curCP());
1316 } else {
1317 // We are seeing a nonempty switch.
1318 sel.load();
1319 if (genCrt)
1320 code.crt.put(TreeInfo.skipParens(selector),
1321 CRT_FLOW_CONTROLLER, startpcCrt, code.curCP());
1322 Env<GenContext> switchEnv = env.dup(swtch, new GenContext());
1323 switchEnv.info.isSwitch = true;
1324
1325 // Compute number of labels and minimum and maximum label values.
1326 // For each case, store its label in an array.
1327 int lo = Integer.MAX_VALUE; // minimum label.
1328 int hi = Integer.MIN_VALUE; // maximum label.
1329 int nlabels = 0; // number of labels.
1330
1331 int[] labels = new int[cases.length()]; // the label array.
1332 int defaultIndex = -1; // the index of the default clause.
1333
1334 List<JCCase> l = cases;
1335 for (int i = 0; i < labels.length; i++) {
1336 if (l.head.labels.head instanceof JCConstantCaseLabel constLabel) {
1337 Assert.check(l.head.labels.size() == 1);
1338 int val = ((Number) constLabel.expr.type.constValue()).intValue();
1339 labels[i] = val;
1340 if (val < lo) lo = val;
1341 if (hi < val) hi = val;
1342 nlabels++;
1343 } else {
1344 Assert.check(defaultIndex == -1);
1345 defaultIndex = i;
1346 }
1347 l = l.tail;
1348 }
1349
1350 // Determine whether to issue a tableswitch or a lookupswitch
1351 // instruction.
1352 long table_space_cost = 4 + ((long) hi - lo + 1); // words
1353 long table_time_cost = 3; // comparisons
1354 long lookup_space_cost = 3 + 2 * (long) nlabels;
1355 long lookup_time_cost = nlabels;
1356 int opcode =
1357 nlabels > 0 &&
1358 table_space_cost + 3 * table_time_cost <=
1359 lookup_space_cost + 3 * lookup_time_cost
1360 ?
1361 tableswitch : lookupswitch;
1362
1363 int startpc = code.curCP(); // the position of the selector operation
1364 code.emitop0(opcode);
1365 code.align(4);
1366 int tableBase = code.curCP(); // the start of the jump table
1367 int[] offsets = null; // a table of offsets for a lookupswitch
1368 code.emit4(-1); // leave space for default offset
1369 if (opcode == tableswitch) {
1370 code.emit4(lo); // minimum label
1371 code.emit4(hi); // maximum label
1372 for (long i = lo; i <= hi; i++) { // leave space for jump table
1373 code.emit4(-1);
1374 }
1375 } else {
1376 code.emit4(nlabels); // number of labels
1377 for (int i = 0; i < nlabels; i++) {
1378 code.emit4(-1); code.emit4(-1); // leave space for lookup table
1379 }
1380 offsets = new int[labels.length];
1381 }
1382 Code.State stateSwitch = code.state.dup();
1383 code.markDead();
1384
1385 // For each case do:
1386 l = cases;
1387 for (int i = 0; i < labels.length; i++) {
1388 JCCase c = l.head;
1389 l = l.tail;
1390
1391 int pc = code.entryPoint(stateSwitch);
1392 // Insert offset directly into code or else into the
1393 // offsets table.
1394 if (i != defaultIndex) {
1395 if (opcode == tableswitch) {
1396 code.put4(
1397 tableBase + 4 * (labels[i] - lo + 3),
1398 pc - startpc);
1399 } else {
1400 offsets[i] = pc - startpc;
1401 }
1402 } else {
1403 code.put4(tableBase, pc - startpc);
1404 }
1405
1406 // Generate code for the statements in this case.
1407 genStats(c.stats, switchEnv, CRT_FLOW_TARGET);
1408 }
1409
1410 if (switchEnv.info.cont != null) {
1411 Assert.check(patternSwitch);
1412 code.resolve(switchEnv.info.cont, switchStart);
1413 }
1414
1415 // Resolve all breaks.
1416 Chain exit = switchEnv.info.exit;
1417 if (exit != null) {
1418 code.resolve(exit);
1432 if (code.get4(t) == -1)
1433 code.put4(t, defaultOffset);
1434 }
1435 } else {
1436 // Sort non-default offsets and copy into lookup table.
1437 if (defaultIndex >= 0)
1438 for (int i = defaultIndex; i < labels.length - 1; i++) {
1439 labels[i] = labels[i+1];
1440 offsets[i] = offsets[i+1];
1441 }
1442 if (nlabels > 0)
1443 qsort2(labels, offsets, 0, nlabels - 1);
1444 for (int i = 0; i < nlabels; i++) {
1445 int caseidx = tableBase + 8 * (i + 1);
1446 code.put4(caseidx, labels[i]);
1447 code.put4(caseidx + 4, offsets[i]);
1448 }
1449 }
1450
1451 if (swtch instanceof JCSwitchExpression) {
1452 // Emit line position for the end of a switch expression
1453 code.statBegin(TreeInfo.endPos(swtch));
1454 }
1455 }
1456 code.endScopes(limit);
1457 }
1458 //where
1459 /** Sort (int) arrays of keys and values
1460 */
1461 static void qsort2(int[] keys, int[] values, int lo, int hi) {
1462 int i = lo;
1463 int j = hi;
1464 int pivot = keys[(i+j)/2];
1465 do {
1466 while (keys[i] < pivot) i++;
1467 while (pivot < keys[j]) j--;
1468 if (i <= j) {
1469 int temp1 = keys[i];
1470 keys[i] = keys[j];
1471 keys[j] = temp1;
1472 int temp2 = values[i];
1473 values[i] = values[j];
1536 @Override
1537 void afterBody() {
1538 if (tree.finalizer != null && (tree.finalizer.flags & BODY_ONLY_FINALIZE) != 0) {
1539 //for body-only finally, remove the GenFinalizer after try body
1540 //so that the finally is not generated to catch bodies:
1541 tryEnv.info.finalize = null;
1542 }
1543 }
1544
1545 };
1546 tryEnv.info.gaps = new ListBuffer<>();
1547 genTry(tree.body, tree.catchers, tryEnv);
1548 }
1549 //where
1550 /** Generate code for a try or synchronized statement
1551 * @param body The body of the try or synchronized statement.
1552 * @param catchers The list of catch clauses.
1553 * @param env The current environment of the body.
1554 */
1555 void genTry(JCTree body, List<JCCatch> catchers, Env<GenContext> env) {
1556 int limit = code.nextreg;
1557 int startpc = code.curCP();
1558 Code.State stateTry = code.state.dup();
1559 genStat(body, env, CRT_BLOCK);
1560 int endpc = code.curCP();
1561 List<Integer> gaps = env.info.gaps.toList();
1562 code.statBegin(TreeInfo.endPos(body));
1563 genFinalizer(env);
1564 code.statBegin(TreeInfo.endPos(env.tree));
1565 Chain exitChain;
1566 boolean actualTry = env.tree.hasTag(TRY);
1567 if (startpc == endpc && actualTry) {
1568 exitChain = code.branch(dontgoto);
1569 } else {
1570 exitChain = code.branch(goto_);
1571 }
1572 endFinalizerGap(env);
1573 env.info.finalize.afterBody();
1574 boolean hasFinalizer =
1575 env.info.finalize != null &&
1576 env.info.finalize.hasFinalizer();
1577 if (startpc != endpc) for (List<JCCatch> l = catchers; l.nonEmpty(); l = l.tail) {
1578 // start off with exception on stack
1579 code.entryPoint(stateTry, l.head.param.sym.type);
1580 genCatch(l.head, env, startpc, endpc, gaps);
1581 genFinalizer(env);
1582 if (hasFinalizer || l.tail.nonEmpty()) {
1583 code.statBegin(TreeInfo.endPos(env.tree));
1584 exitChain = Code.mergeChains(exitChain,
1585 code.branch(goto_));
1586 }
1587 endFinalizerGap(env);
1588 }
1589 if (hasFinalizer && (startpc != endpc || !actualTry)) {
1590 // Create a new register segment to avoid allocating
1591 // the same variables in finalizers and other statements.
1592 code.newRegSegment();
1593
1594 // Add a catch-all clause.
1595
1596 // start off with exception on stack
1597 int catchallpc = code.entryPoint(stateTry, syms.throwableType);
1598
1599 // Register all exception ranges for catch all clause.
1600 // The range of the catch all clause is from the beginning
1601 // of the try or synchronized block until the present
1602 // code pointer excluding all gaps in the current
1603 // environment's GenContext.
1604 int startseg = startpc;
1605 while (env.info.gaps.nonEmpty()) {
1606 int endseg = env.info.gaps.next().intValue();
1607 registerCatch(body.pos(), startseg, endseg,
1608 catchallpc, 0);
1609 startseg = env.info.gaps.next().intValue();
1610 }
1611 code.statBegin(TreeInfo.finalizerPos(env.tree, PosKind.FIRST_STAT_POS));
1612 code.markStatBegin();
1613
1614 Item excVar = makeTemp(syms.throwableType);
1615 excVar.store();
1616 genFinalizer(env);
1617 code.resolvePending();
1618 code.statBegin(TreeInfo.finalizerPos(env.tree, PosKind.END_POS));
1619 code.markStatBegin();
1620
1621 excVar.load();
1622 registerCatch(body.pos(), startseg,
1623 env.info.gaps.next().intValue(),
1624 catchallpc, 0);
1625 code.emitop0(athrow);
1626 code.markDead();
1627
1628 // If there are jsr's to this finalizer, ...
1629 if (env.info.cont != null) {
1630 // Resolve all jsr's.
1631 code.resolve(env.info.cont);
1632
1633 // Mark statement line number
1634 code.statBegin(TreeInfo.finalizerPos(env.tree, PosKind.FIRST_STAT_POS));
1635 code.markStatBegin();
1636
1637 // Save return address.
1638 LocalItem retVar = makeTemp(syms.throwableType);
1639 retVar.store();
1640
1641 // Generate finalizer code.
1642 env.info.finalize.genLast();
1643
1644 // Return.
1747 /** Register a catch clause in the "Exceptions" code-attribute.
1748 */
1749 void registerCatch(DiagnosticPosition pos,
1750 int startpc, int endpc,
1751 int handler_pc, int catch_type) {
1752 char startpc1 = (char)startpc;
1753 char endpc1 = (char)endpc;
1754 char handler_pc1 = (char)handler_pc;
1755 if (startpc1 == startpc &&
1756 endpc1 == endpc &&
1757 handler_pc1 == handler_pc) {
1758 code.addCatch(startpc1, endpc1, handler_pc1,
1759 (char)catch_type);
1760 } else {
1761 log.error(pos, Errors.LimitCodeTooLargeForTryStmt);
1762 nerrs++;
1763 }
1764 }
1765
1766 public void visitIf(JCIf tree) {
1767 int limit = code.nextreg;
1768 Chain thenExit = null;
1769 Assert.check(code.isStatementStart());
1770 CondItem c = genCond(TreeInfo.skipParens(tree.cond),
1771 CRT_FLOW_CONTROLLER);
1772 Chain elseChain = c.jumpFalse();
1773 Assert.check(code.isStatementStart());
1774 if (!c.isFalse()) {
1775 code.resolve(c.trueJumps);
1776 genStat(tree.thenpart, env, CRT_STATEMENT | CRT_FLOW_TARGET);
1777 thenExit = code.branch(goto_);
1778 }
1779 if (elseChain != null) {
1780 code.resolve(elseChain);
1781 if (tree.elsepart != null) {
1782 genStat(tree.elsepart, env,CRT_STATEMENT | CRT_FLOW_TARGET);
1783 }
1784 }
1785 code.resolve(thenExit);
1786 code.endScopes(limit);
1787 Assert.check(code.isStatementStart());
1788 }
1789
1790 public void visitExec(JCExpressionStatement tree) {
1791 // Optimize x++ to ++x and x-- to --x.
2078 nerrs++;
2079 }
2080 int elemcode = Code.arraycode(elemtype);
2081 if (elemcode == 0 || (elemcode == 1 && ndims == 1)) {
2082 code.emitAnewarray(makeRef(pos, elemtype), type);
2083 } else if (elemcode == 1) {
2084 code.emitMultianewarray(ndims, makeRef(pos, type), type);
2085 } else {
2086 code.emitNewarray(elemcode, type);
2087 }
2088 return items.makeStackItem(type);
2089 }
2090
2091 public void visitParens(JCParens tree) {
2092 result = genExpr(tree.expr, tree.expr.type);
2093 }
2094
2095 public void visitAssign(JCAssign tree) {
2096 Item l = genExpr(tree.lhs, tree.lhs.type);
2097 genExpr(tree.rhs, tree.lhs.type).load();
2098 if (tree.rhs.type.hasTag(BOT)) {
2099 /* This is just a case of widening reference conversion that per 5.1.5 simply calls
2100 for "regarding a reference as having some other type in a manner that can be proved
2101 correct at compile time."
2102 */
2103 code.state.forceStackTop(tree.lhs.type);
2104 }
2105 result = items.makeAssignItem(l);
2106 }
2107
2108 public void visitAssignop(JCAssignOp tree) {
2109 OperatorSymbol operator = tree.operator;
2110 Item l;
2111 if (operator.opcode == string_add) {
2112 l = concat.makeConcat(tree);
2113 } else {
2114 // Generate code for first expression
2115 l = genExpr(tree.lhs, tree.lhs.type);
2116
2117 // If we have an increment of -32768 to +32767 of a local
2356 items.makeThisItem().load();
2357 sym = binaryQualifier(sym, env.enclClass.type);
2358 result = items.makeMemberItem(sym, nonVirtualForPrivateAccess(sym));
2359 }
2360 }
2361
2362 //where
2363 private boolean nonVirtualForPrivateAccess(Symbol sym) {
2364 boolean useVirtual = target.hasVirtualPrivateInvoke() &&
2365 !disableVirtualizedPrivateInvoke;
2366 return !useVirtual && ((sym.flags() & PRIVATE) != 0);
2367 }
2368
2369 public void visitSelect(JCFieldAccess tree) {
2370 Symbol sym = tree.sym;
2371
2372 if (tree.name == names._class) {
2373 code.emitLdc((LoadableConstant)checkDimension(tree.pos(), tree.selected.type));
2374 result = items.makeStackItem(pt);
2375 return;
2376 }
2377
2378 Symbol ssym = TreeInfo.symbol(tree.selected);
2379
2380 // Are we selecting via super?
2381 boolean selectSuper =
2382 ssym != null && (ssym.kind == TYP || ssym.name == names._super);
2383
2384 // Are we accessing a member of the superclass in an access method
2385 // resulting from a qualified super?
2386 boolean accessSuper = isAccessSuper(env.enclMethod);
2387
2388 Item base = (selectSuper)
2389 ? items.makeSuperItem()
2390 : genExpr(tree.selected, tree.selected.type);
2391
2392 if (sym.kind == VAR && ((VarSymbol) sym).getConstValue() != null) {
2393 // We are seeing a variable that is constant but its selecting
2394 // expression is not.
2395 if ((sym.flags() & STATIC) != 0) {
2396 if (!selectSuper && (ssym == null || ssym.kind != TYP))
|
1 /*
2 * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
80 private final StringConcat concat;
81
82 /** Format of stackmap tables to be generated. */
83 private final Code.StackMapFormat stackMap;
84
85 /** A type that serves as the expected type for all method expressions.
86 */
87 private final Type methodType;
88
89 public static Gen instance(Context context) {
90 Gen instance = context.get(genKey);
91 if (instance == null)
92 instance = new Gen(context);
93 return instance;
94 }
95
96 /** Constant pool writer, set by genClass.
97 */
98 final PoolWriter poolWriter;
99
100 private final UnsetFieldsInfo unsetFieldsInfo;
101
102 @SuppressWarnings("this-escape")
103 protected Gen(Context context) {
104 context.put(genKey, this);
105
106 names = Names.instance(context);
107 log = Log.instance(context);
108 syms = Symtab.instance(context);
109 chk = Check.instance(context);
110 rs = Resolve.instance(context);
111 make = TreeMaker.instance(context);
112 target = Target.instance(context);
113 types = Types.instance(context);
114 concat = StringConcat.instance(context);
115
116 methodType = new MethodType(null, null, null, syms.methodClass);
117 accessDollar = "access" + target.syntheticNameChar();
118 lower = Lower.instance(context);
119
120 Options options = Options.instance(context);
121 lineDebugInfo =
122 options.isUnset(G_CUSTOM) ||
123 options.isSet(G_CUSTOM, "lines");
124 varDebugInfo =
125 options.isUnset(G_CUSTOM)
126 ? options.isSet(G)
127 : options.isSet(G_CUSTOM, "vars");
128 genCrt = options.isSet(XJCOV);
129 debugCode = options.isSet("debug.code");
130 disableVirtualizedPrivateInvoke = options.isSet("disableVirtualizedPrivateInvoke");
131 poolWriter = new PoolWriter(types, names);
132 unsetFieldsInfo = UnsetFieldsInfo.instance(context);
133
134 // ignore cldc because we cannot have both stackmap formats
135 this.stackMap = StackMapFormat.JSR202;
136 annotate = Annotate.instance(context);
137 qualifiedSymbolCache = new HashMap<>();
138 generateAssertUnsetFieldsFrame = options.isSet("generateAssertUnsetFieldsFrame");
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 boolean generateAssertUnsetFieldsFrame;
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;
412 boolean hasFinally(JCTree target, Env<GenContext> env) {
413 while (env.tree != target) {
414 if (env.tree.hasTag(TRY) && env.info.finalize.hasFinalizer())
415 return true;
416 env = env.next;
417 }
418 return false;
419 }
420
421 /* ************************************************************************
422 * Normalizing class-members.
423 *************************************************************************/
424
425 /** Distribute member initializer code into constructors and {@code <clinit>}
426 * method.
427 * @param defs The list of class member declarations.
428 * @param c The enclosing class.
429 */
430 List<JCTree> normalizeDefs(List<JCTree> defs, ClassSymbol c) {
431 ListBuffer<JCStatement> initCode = new ListBuffer<>();
432 // only used for value classes
433 ListBuffer<JCStatement> initBlocks = new ListBuffer<>();
434 ListBuffer<Attribute.TypeCompound> initTAs = new ListBuffer<>();
435 ListBuffer<JCStatement> clinitCode = new ListBuffer<>();
436 ListBuffer<Attribute.TypeCompound> clinitTAs = new ListBuffer<>();
437 ListBuffer<JCTree> methodDefs = new ListBuffer<>();
438 // Sort definitions into three listbuffers:
439 // - initCode for instance initializers
440 // - clinitCode for class initializers
441 // - methodDefs for method definitions
442 for (List<JCTree> l = defs; l.nonEmpty(); l = l.tail) {
443 JCTree def = l.head;
444 switch (def.getTag()) {
445 case BLOCK:
446 JCBlock block = (JCBlock)def;
447 if ((block.flags & STATIC) != 0)
448 clinitCode.append(block);
449 else if ((block.flags & SYNTHETIC) == 0) {
450 if (c.isValueClass() || c.hasStrict()) {
451 initBlocks.append(block);
452 } else {
453 initCode.append(block);
454 }
455 }
456 break;
457 case METHODDEF:
458 methodDefs.append(def);
459 break;
460 case VARDEF:
461 JCVariableDecl vdef = (JCVariableDecl) def;
462 VarSymbol sym = vdef.sym;
463 checkDimension(vdef.pos(), sym.type);
464 if (vdef.init != null) {
465 if ((sym.flags() & STATIC) == 0) {
466 // Always initialize instance variables.
467 JCStatement init = make.at(vdef.pos()).
468 Assignment(sym, vdef.init);
469 initCode.append(init);
470 endPosTable.replaceTree(vdef, init);
471 initTAs.addAll(getAndRemoveNonFieldTAs(sym));
472 } else if (sym.getConstValue() == null) {
473 // Initialize class (static) variables only if
474 // they are not compile-time constants.
475 JCStatement init = make.at(vdef.pos).
476 Assignment(sym, vdef.init);
477 clinitCode.append(init);
478 endPosTable.replaceTree(vdef, init);
479 clinitTAs.addAll(getAndRemoveNonFieldTAs(sym));
480 } else {
481 checkStringConstant(vdef.init.pos(), sym.getConstValue());
482 /* if the init contains a reference to an external class, add it to the
483 * constant's pool
484 */
485 vdef.init.accept(classReferenceVisitor);
486 }
487 }
488 break;
489 default:
490 Assert.error();
491 }
492 }
493 // Insert any instance initializers into all constructors.
494 if (initCode.length() != 0 || initBlocks.length() != 0) {
495 initTAs.addAll(c.getInitTypeAttributes());
496 List<Attribute.TypeCompound> initTAlist = initTAs.toList();
497 for (JCTree t : methodDefs) {
498 normalizeMethod((JCMethodDecl)t, initCode.toList(), initBlocks.toList(), initTAlist);
499 }
500 }
501 // If there are class initializers, create a <clinit> method
502 // that contains them as its body.
503 if (clinitCode.length() != 0) {
504 MethodSymbol clinit = new MethodSymbol(
505 STATIC | (c.flags() & STRICTFP),
506 names.clinit,
507 new MethodType(
508 List.nil(), syms.voidType,
509 List.nil(), syms.methodClass),
510 c);
511 c.members().enter(clinit);
512 List<JCStatement> clinitStats = clinitCode.toList();
513 JCBlock block = make.at(clinitStats.head.pos()).Block(0, clinitStats);
514 block.endpos = TreeInfo.endPos(clinitStats.last());
515 methodDefs.append(make.MethodDef(clinit, block));
516
517 if (!clinitTAs.isEmpty())
518 clinit.appendUniqueTypeAttributes(clinitTAs.toList());
541
542 /** Check a constant value and report if it is a string that is
543 * too large.
544 */
545 private void checkStringConstant(DiagnosticPosition pos, Object constValue) {
546 if (nerrs != 0 || // only complain about a long string once
547 constValue == null ||
548 !(constValue instanceof String str) ||
549 str.length() < PoolWriter.MAX_STRING_LENGTH)
550 return;
551 log.error(pos, Errors.LimitString);
552 nerrs++;
553 }
554
555 /** Insert instance initializer code into constructors prior to the super() call.
556 * @param md The tree potentially representing a
557 * constructor's definition.
558 * @param initCode The list of instance initializer statements.
559 * @param initTAs Type annotations from the initializer expression.
560 */
561 void normalizeMethod(JCMethodDecl md, List<JCStatement> initCode, List<JCStatement> initBlocks, List<TypeCompound> initTAs) {
562 if (TreeInfo.isConstructor(md) && TreeInfo.hasConstructorCall(md, names._super)) {
563 // We are seeing a constructor that has a super() call.
564 // Find the super() invocation and append the given initializer code.
565 if (md.sym.owner.isValueClass() || md.sym.owner.hasStrict()) {
566 rewriteInitializersIfNeeded(md, initCode);
567 md.body.stats = initCode.appendList(md.body.stats);
568 TreeInfo.mapSuperCalls(md.body, supercall -> make.Block(0, initBlocks.prepend(supercall)));
569 } else {
570 TreeInfo.mapSuperCalls(md.body, supercall -> make.Block(0, initCode.prepend(supercall)));
571 }
572
573 if (md.body.endpos == Position.NOPOS)
574 md.body.endpos = TreeInfo.endPos(md.body.stats.last());
575
576 md.sym.appendUniqueTypeAttributes(initTAs);
577 }
578 }
579
580 void rewriteInitializersIfNeeded(JCMethodDecl md, List<JCStatement> initCode) {
581 if (lower.initializerOuterThis.containsKey(md.sym.owner)) {
582 InitializerVisitor initializerVisitor = new InitializerVisitor(md, lower.initializerOuterThis.get(md.sym.owner));
583 for (JCStatement init : initCode) {
584 initializerVisitor.scan(init);
585 }
586 }
587 }
588
589 public static class InitializerVisitor extends TreeScanner {
590 JCMethodDecl md;
591 Set<JCExpression> exprSet;
592
593 public InitializerVisitor(JCMethodDecl md, Set<JCExpression> exprSet) {
594 this.md = md;
595 this.exprSet = exprSet;
596 }
597
598 @Override
599 public void visitTree(JCTree tree) {}
600
601 @Override
602 public void visitIdent(JCIdent tree) {
603 if (exprSet.contains(tree)) {
604 for (JCVariableDecl param: md.params) {
605 if (param.name == tree.name &&
606 ((param.sym.flags_field & (MANDATED | NOOUTERTHIS)) == (MANDATED | NOOUTERTHIS))) {
607 tree.sym = param.sym;
608 }
609 }
610 }
611 }
612 }
613
614 /* ************************************************************************
615 * Traversal methods
616 *************************************************************************/
617
618 /** Visitor argument: The current environment.
619 */
620 Env<GenContext> env;
621
622 /** Visitor argument: The expected type (prototype).
623 */
624 Type pt;
625
626 /** Visitor result: The item representing the computed value.
627 */
628 Item result;
629
630 /** Visitor method: generate code for a definition, catching and reporting
631 * any completion failures.
632 * @param tree The definition to be visited.
633 * @param env The environment current at the definition.
978 // Count up extra parameters
979 if (meth.isConstructor()) {
980 extras++;
981 if (meth.enclClass().isInner() &&
982 !meth.enclClass().isStatic()) {
983 extras++;
984 }
985 } else if ((tree.mods.flags & STATIC) == 0) {
986 extras++;
987 }
988 // System.err.println("Generating " + meth + " in " + meth.owner); //DEBUG
989 if (Code.width(types.erasure(env.enclMethod.sym.type).getParameterTypes()) + extras >
990 ClassFile.MAX_PARAMETERS) {
991 log.error(tree.pos(), Errors.LimitParameters);
992 nerrs++;
993 }
994
995 else if (tree.body != null) {
996 // Create a new code structure and initialize it.
997 int startpcCrt = initCode(tree, env, fatcode);
998 Set<VarSymbol> prevUnsetFields = code.currentUnsetFields;
999 if (meth.isConstructor()) {
1000 code.currentUnsetFields = unsetFieldsInfo.getUnsetFields(env.enclClass.sym, tree.body);
1001 code.initialUnsetFields = unsetFieldsInfo.getUnsetFields(env.enclClass.sym, tree.body);
1002 }
1003
1004 try {
1005 genStat(tree.body, env);
1006 } catch (CodeSizeOverflow e) {
1007 // Failed due to code limit, try again with jsr/ret
1008 startpcCrt = initCode(tree, env, fatcode);
1009 genStat(tree.body, env);
1010 } finally {
1011 code.currentUnsetFields = prevUnsetFields;
1012 }
1013
1014 if (code.state.stacksize != 0) {
1015 log.error(tree.body.pos(), Errors.StackSimError(tree.sym));
1016 throw new AssertionError();
1017 }
1018
1019 // If last statement could complete normally, insert a
1020 // return at the end.
1021 if (code.isAlive()) {
1022 code.statBegin(TreeInfo.endPos(tree.body));
1023 if (env.enclMethod == null ||
1024 env.enclMethod.sym.type.getReturnType().hasTag(VOID)) {
1025 code.emitop0(return_);
1026 } else {
1027 // sometime dead code seems alive (4415991);
1028 // generate a small loop instead
1029 int startpc = code.entryPoint();
1030 CondItem c = items.makeCondItem(goto_);
1031 code.resolve(c.jumpTrue(), startpc);
1060
1061 // Fill in type annotation positions for exception parameters
1062 code.fillExceptionParameterPositions();
1063 }
1064 }
1065
1066 private int initCode(JCMethodDecl tree, Env<GenContext> env, boolean fatcode) {
1067 MethodSymbol meth = tree.sym;
1068
1069 // Create a new code structure.
1070 meth.code = code = new Code(meth,
1071 fatcode,
1072 lineDebugInfo ? toplevel.lineMap : null,
1073 varDebugInfo,
1074 stackMap,
1075 debugCode,
1076 genCrt ? new CRTable(tree, env.toplevel.endPositions)
1077 : null,
1078 syms,
1079 types,
1080 poolWriter,
1081 generateAssertUnsetFieldsFrame);
1082 items = new Items(poolWriter, code, syms, types);
1083 if (code.debugCode) {
1084 System.err.println(meth + " for body " + tree);
1085 }
1086
1087 // If method is not static, create a new local variable address
1088 // for `this'.
1089 if ((tree.mods.flags & STATIC) == 0) {
1090 Type selfType = meth.owner.type;
1091 if (meth.isConstructor() && selfType != syms.objectType)
1092 selfType = UninitializedType.uninitializedThis(selfType);
1093 code.setDefined(
1094 code.newLocal(
1095 new VarSymbol(FINAL, names._this, selfType, meth.owner)));
1096 }
1097
1098 // Mark all parameters as defined from the beginning of
1099 // the method.
1100 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
1101 checkDimension(l.head.pos(), l.head.sym.type);
1197 public void visitForLoop(JCForLoop tree) {
1198 int limit = code.nextreg;
1199 genStats(tree.init, env);
1200 genLoop(tree, tree.body, tree.cond, tree.step, true);
1201 code.endScopes(limit);
1202 }
1203 //where
1204 /** Generate code for a loop.
1205 * @param loop The tree representing the loop.
1206 * @param body The loop's body.
1207 * @param cond The loop's controlling condition.
1208 * @param step "Step" statements to be inserted at end of
1209 * each iteration.
1210 * @param testFirst True if the loop test belongs before the body.
1211 */
1212 private void genLoop(JCStatement loop,
1213 JCStatement body,
1214 JCExpression cond,
1215 List<JCExpressionStatement> step,
1216 boolean testFirst) {
1217 Set<VarSymbol> prevCodeUnsetFields = code.currentUnsetFields;
1218 try {
1219 genLoopHelper(loop, body, cond, step, testFirst);
1220 } finally {
1221 code.currentUnsetFields = prevCodeUnsetFields;
1222 }
1223 }
1224
1225 private void genLoopHelper(JCStatement loop,
1226 JCStatement body,
1227 JCExpression cond,
1228 List<JCExpressionStatement> step,
1229 boolean testFirst) {
1230 Env<GenContext> loopEnv = env.dup(loop, new GenContext());
1231 int startpc = code.entryPoint();
1232 if (testFirst) { //while or for loop
1233 CondItem c;
1234 if (cond != null) {
1235 code.statBegin(cond.pos);
1236 Assert.check(code.isStatementStart());
1237 c = genCond(TreeInfo.skipParens(cond), CRT_FLOW_CONTROLLER);
1238 } else {
1239 c = items.makeCondItem(goto_);
1240 }
1241 Chain loopDone = c.jumpFalse();
1242 code.resolve(c.trueJumps);
1243 Assert.check(code.isStatementStart());
1244 genStat(body, loopEnv, CRT_STATEMENT | CRT_FLOW_TARGET);
1245 code.resolve(loopEnv.info.cont);
1246 genStats(step, loopEnv);
1247 code.resolve(code.branch(goto_), startpc);
1248 code.resolve(loopDone);
1249 } else {
1276 }
1277
1278 public void visitLabelled(JCLabeledStatement tree) {
1279 Env<GenContext> localEnv = env.dup(tree, new GenContext());
1280 genStat(tree.body, localEnv, CRT_STATEMENT);
1281 Chain exit = localEnv.info.exit;
1282 if (exit != null) {
1283 code.resolve(exit);
1284 exit.state.defined.excludeFrom(code.nextreg);
1285 }
1286 }
1287
1288 public void visitSwitch(JCSwitch tree) {
1289 handleSwitch(tree, tree.selector, tree.cases, tree.patternSwitch);
1290 }
1291
1292 @Override
1293 public void visitSwitchExpression(JCSwitchExpression tree) {
1294 code.resolvePending();
1295 boolean prevInCondSwitchExpression = inCondSwitchExpression;
1296 Set<VarSymbol> prevCodeUnsetFields = code.currentUnsetFields;
1297 try {
1298 inCondSwitchExpression = false;
1299 doHandleSwitchExpression(tree);
1300 } finally {
1301 inCondSwitchExpression = prevInCondSwitchExpression;
1302 code.currentUnsetFields = prevCodeUnsetFields;
1303 }
1304 result = items.makeStackItem(pt);
1305 }
1306
1307 private void doHandleSwitchExpression(JCSwitchExpression tree) {
1308 List<LocalItem> prevStackBeforeSwitchExpression = stackBeforeSwitchExpression;
1309 LocalItem prevSwitchResult = switchResult;
1310 int limit = code.nextreg;
1311 try {
1312 stackBeforeSwitchExpression = List.nil();
1313 switchResult = null;
1314 if (hasTry(tree)) {
1315 //if the switch expression contains try-catch, the catch handlers need to have
1316 //an empty stack. So stash whole stack to local variables, and restore it before
1317 //breaks:
1318 while (code.state.stacksize > 0) {
1319 Type type = code.state.peek();
1320 Name varName = names.fromString(target.syntheticNameChar() +
1321 "stack" +
1322 target.syntheticNameChar() +
1358 hasTry = true;
1359 }
1360
1361 @Override
1362 public void visitClassDef(JCClassDecl tree) {
1363 }
1364
1365 @Override
1366 public void visitLambda(JCLambda tree) {
1367 }
1368 };
1369
1370 HasTryScanner hasTryScanner = new HasTryScanner();
1371
1372 hasTryScanner.scan(tree);
1373 return hasTryScanner.hasTry;
1374 }
1375
1376 private void handleSwitch(JCTree swtch, JCExpression selector, List<JCCase> cases,
1377 boolean patternSwitch) {
1378 Set<VarSymbol> prevCodeUnsetFields = code.currentUnsetFields;
1379 try {
1380 handleSwitchHelper(swtch, selector, cases, patternSwitch);
1381 } finally {
1382 code.currentUnsetFields = prevCodeUnsetFields;
1383 }
1384 }
1385
1386 void handleSwitchHelper(JCTree swtch, JCExpression selector, List<JCCase> cases,
1387 boolean patternSwitch) {
1388 int limit = code.nextreg;
1389 Assert.check(!selector.type.hasTag(CLASS));
1390 int switchStart = patternSwitch ? code.entryPoint() : -1;
1391 int startpcCrt = genCrt ? code.curCP() : 0;
1392 Assert.check(code.isStatementStart());
1393 Item sel = genExpr(selector, syms.intType);
1394 if (cases.isEmpty()) {
1395 // We are seeing: switch <sel> {}
1396 sel.load().drop();
1397 if (genCrt)
1398 code.crt.put(TreeInfo.skipParens(selector),
1399 CRT_FLOW_CONTROLLER, startpcCrt, code.curCP());
1400 } else {
1401 // We are seeing a nonempty switch.
1402 sel.load();
1403 if (genCrt)
1404 code.crt.put(TreeInfo.skipParens(selector),
1405 CRT_FLOW_CONTROLLER, startpcCrt, code.curCP());
1406 Env<GenContext> switchEnv = env.dup(swtch, new GenContext());
1407 switchEnv.info.isSwitch = true;
1408
1409 // Compute number of labels and minimum and maximum label values.
1410 // For each case, store its label in an array.
1411 int lo = Integer.MAX_VALUE; // minimum label.
1412 int hi = Integer.MIN_VALUE; // maximum label.
1413 int nlabels = 0; // number of labels.
1414
1415 int[] labels = new int[cases.length()]; // the label array.
1416 int defaultIndex = -1; // the index of the default clause.
1417
1418 List<JCCase> l = cases;
1419 for (int i = 0; i < labels.length; i++) {
1420 if (l.head.labels.head instanceof JCConstantCaseLabel constLabel) {
1421 Assert.check(l.head.labels.size() == 1);
1422 int val = ((Number) constLabel.expr.type.constValue()).intValue();
1423 labels[i] = val;
1424 if (val < lo) lo = val;
1425 if (hi < val) hi = val;
1426 nlabels++;
1427 } else {
1428 Assert.check(defaultIndex == -1);
1429 defaultIndex = i;
1430 }
1431 l = l.tail;
1432 }
1433
1434 // Determine whether to issue a tableswitch or a lookupswitch
1435 // instruction.
1436 long table_space_cost = 4 + ((long) hi - lo + 1); // words
1437 long table_time_cost = 3; // comparisons
1438 long lookup_space_cost = 3 + 2 * (long) nlabels;
1439 long lookup_time_cost = nlabels;
1440 int opcode =
1441 nlabels > 0 &&
1442 table_space_cost + 3 * table_time_cost <=
1443 lookup_space_cost + 3 * lookup_time_cost
1444 ?
1445 tableswitch : lookupswitch;
1446
1447 int startpc = code.curCP(); // the position of the selector operation
1448 code.emitop0(opcode);
1449 code.align(4);
1450 int tableBase = code.curCP(); // the start of the jump table
1451 int[] offsets = null; // a table of offsets for a lookupswitch
1452 code.emit4(-1); // leave space for default offset
1453 if (opcode == tableswitch) {
1454 code.emit4(lo); // minimum label
1455 code.emit4(hi); // maximum label
1456 for (long i = lo; i <= hi; i++) { // leave space for jump table
1457 code.emit4(-1);
1458 }
1459 } else {
1460 code.emit4(nlabels); // number of labels
1461 for (int i = 0; i < nlabels; i++) {
1462 code.emit4(-1); code.emit4(-1); // leave space for lookup table
1463 }
1464 offsets = new int[labels.length];
1465 }
1466 Code.State stateSwitch = code.state.dup();
1467 code.markDead();
1468
1469 // For each case do:
1470 l = cases;
1471 for (int i = 0; i < labels.length; i++) {
1472 JCCase c = l.head;
1473 l = l.tail;
1474
1475 int pc = code.entryPoint(stateSwitch);
1476 // Insert offset directly into code or else into the
1477 // offsets table.
1478 if (i != defaultIndex) {
1479 if (opcode == tableswitch) {
1480 code.put4(
1481 tableBase + 4 * (labels[i] - lo + 3),
1482 pc - startpc);
1483 } else {
1484 offsets[i] = pc - startpc;
1485 }
1486 } else {
1487 code.put4(tableBase, pc - startpc);
1488 }
1489
1490 // Generate code for the statements in this case.
1491 genStats(c.stats, switchEnv, CRT_FLOW_TARGET);
1492 }
1493
1494 if (switchEnv.info.cont != null) {
1495 Assert.check(patternSwitch);
1496 code.resolve(switchEnv.info.cont, switchStart);
1497 }
1498
1499 // Resolve all breaks.
1500 Chain exit = switchEnv.info.exit;
1501 if (exit != null) {
1502 code.resolve(exit);
1516 if (code.get4(t) == -1)
1517 code.put4(t, defaultOffset);
1518 }
1519 } else {
1520 // Sort non-default offsets and copy into lookup table.
1521 if (defaultIndex >= 0)
1522 for (int i = defaultIndex; i < labels.length - 1; i++) {
1523 labels[i] = labels[i+1];
1524 offsets[i] = offsets[i+1];
1525 }
1526 if (nlabels > 0)
1527 qsort2(labels, offsets, 0, nlabels - 1);
1528 for (int i = 0; i < nlabels; i++) {
1529 int caseidx = tableBase + 8 * (i + 1);
1530 code.put4(caseidx, labels[i]);
1531 code.put4(caseidx + 4, offsets[i]);
1532 }
1533 }
1534
1535 if (swtch instanceof JCSwitchExpression) {
1536 // Emit line position for the end of a switch expression
1537 code.statBegin(TreeInfo.endPos(swtch));
1538 }
1539 }
1540 code.endScopes(limit);
1541 }
1542 //where
1543 /** Sort (int) arrays of keys and values
1544 */
1545 static void qsort2(int[] keys, int[] values, int lo, int hi) {
1546 int i = lo;
1547 int j = hi;
1548 int pivot = keys[(i+j)/2];
1549 do {
1550 while (keys[i] < pivot) i++;
1551 while (pivot < keys[j]) j--;
1552 if (i <= j) {
1553 int temp1 = keys[i];
1554 keys[i] = keys[j];
1555 keys[j] = temp1;
1556 int temp2 = values[i];
1557 values[i] = values[j];
1620 @Override
1621 void afterBody() {
1622 if (tree.finalizer != null && (tree.finalizer.flags & BODY_ONLY_FINALIZE) != 0) {
1623 //for body-only finally, remove the GenFinalizer after try body
1624 //so that the finally is not generated to catch bodies:
1625 tryEnv.info.finalize = null;
1626 }
1627 }
1628
1629 };
1630 tryEnv.info.gaps = new ListBuffer<>();
1631 genTry(tree.body, tree.catchers, tryEnv);
1632 }
1633 //where
1634 /** Generate code for a try or synchronized statement
1635 * @param body The body of the try or synchronized statement.
1636 * @param catchers The list of catch clauses.
1637 * @param env The current environment of the body.
1638 */
1639 void genTry(JCTree body, List<JCCatch> catchers, Env<GenContext> env) {
1640 Set<VarSymbol> prevCodeUnsetFields = code.currentUnsetFields;
1641 try {
1642 genTryHelper(body, catchers, env);
1643 } finally {
1644 code.currentUnsetFields = prevCodeUnsetFields;
1645 }
1646 }
1647
1648 void genTryHelper(JCTree body, List<JCCatch> catchers, Env<GenContext> env) {
1649 int limit = code.nextreg;
1650 int startpc = code.curCP();
1651 Code.State stateTry = code.state.dup();
1652 genStat(body, env, CRT_BLOCK);
1653 int endpc = code.curCP();
1654 List<Integer> gaps = env.info.gaps.toList();
1655 code.statBegin(TreeInfo.endPos(body));
1656 genFinalizer(env);
1657 code.statBegin(TreeInfo.endPos(env.tree));
1658 Chain exitChain;
1659 boolean actualTry = env.tree.hasTag(TRY);
1660 if (startpc == endpc && actualTry) {
1661 exitChain = code.branch(dontgoto);
1662 } else {
1663 exitChain = code.branch(goto_);
1664 }
1665 endFinalizerGap(env);
1666 env.info.finalize.afterBody();
1667 boolean hasFinalizer =
1668 env.info.finalize != null &&
1669 env.info.finalize.hasFinalizer();
1670 if (startpc != endpc) for (List<JCCatch> l = catchers; l.nonEmpty(); l = l.tail) {
1671 // start off with exception on stack
1672 code.entryPoint(stateTry, l.head.param.sym.type);
1673 genCatch(l.head, env, startpc, endpc, gaps);
1674 genFinalizer(env);
1675 if (hasFinalizer || l.tail.nonEmpty()) {
1676 code.statBegin(TreeInfo.endPos(env.tree));
1677 exitChain = Code.mergeChains(exitChain,
1678 code.branch(goto_));
1679 }
1680 endFinalizerGap(env);
1681 }
1682 if (hasFinalizer && (startpc != endpc || !actualTry)) {
1683 // Create a new register segment to avoid allocating
1684 // the same variables in finalizers and other statements.
1685 code.newRegSegment();
1686
1687 // Add a catch-all clause.
1688
1689 // start off with exception on stack
1690 int catchallpc = code.entryPoint(stateTry, syms.throwableType);
1691
1692 // Register all exception ranges for catch all clause.
1693 // The range of the catch all clause is from the beginning
1694 // of the try or synchronized block until the present
1695 // code pointer excluding all gaps in the current
1696 // environment's GenContext.
1697 int startseg = startpc;
1698 while (env.info.gaps.nonEmpty()) {
1699 int endseg = env.info.gaps.next().intValue();
1700 registerCatch(body.pos(), startseg, endseg,
1701 catchallpc, 0);
1702 startseg = env.info.gaps.next().intValue();
1703 }
1704 code.statBegin(TreeInfo.finalizerPos(env.tree, PosKind.FIRST_STAT_POS));
1705 code.markStatBegin();
1706
1707 Item excVar = makeTemp(syms.throwableType);
1708 excVar.store();
1709 genFinalizer(env);
1710 code.resolvePending();
1711 code.statBegin(TreeInfo.finalizerPos(env.tree, PosKind.END_POS));
1712 code.markStatBegin();
1713
1714 excVar.load();
1715 registerCatch(body.pos(), startseg,
1716 env.info.gaps.next().intValue(),
1717 catchallpc, 0);
1718 code.emitop0(athrow);
1719 code.markDead();
1720
1721 // If there are jsr's to this finalizer, ...
1722 if (env.info.cont != null) {
1723 // Resolve all jsr's.
1724 code.resolve(env.info.cont);
1725
1726 // Mark statement line number
1727 code.statBegin(TreeInfo.finalizerPos(env.tree, PosKind.FIRST_STAT_POS));
1728 code.markStatBegin();
1729
1730 // Save return address.
1731 LocalItem retVar = makeTemp(syms.throwableType);
1732 retVar.store();
1733
1734 // Generate finalizer code.
1735 env.info.finalize.genLast();
1736
1737 // Return.
1840 /** Register a catch clause in the "Exceptions" code-attribute.
1841 */
1842 void registerCatch(DiagnosticPosition pos,
1843 int startpc, int endpc,
1844 int handler_pc, int catch_type) {
1845 char startpc1 = (char)startpc;
1846 char endpc1 = (char)endpc;
1847 char handler_pc1 = (char)handler_pc;
1848 if (startpc1 == startpc &&
1849 endpc1 == endpc &&
1850 handler_pc1 == handler_pc) {
1851 code.addCatch(startpc1, endpc1, handler_pc1,
1852 (char)catch_type);
1853 } else {
1854 log.error(pos, Errors.LimitCodeTooLargeForTryStmt);
1855 nerrs++;
1856 }
1857 }
1858
1859 public void visitIf(JCIf tree) {
1860 Set<VarSymbol> prevCodeUnsetFields = code.currentUnsetFields;
1861 try {
1862 visitIfHelper(tree);
1863 } finally {
1864 code.currentUnsetFields = prevCodeUnsetFields;
1865 }
1866 }
1867
1868 public void visitIfHelper(JCIf tree) {
1869 int limit = code.nextreg;
1870 Chain thenExit = null;
1871 Assert.check(code.isStatementStart());
1872 CondItem c = genCond(TreeInfo.skipParens(tree.cond),
1873 CRT_FLOW_CONTROLLER);
1874 Chain elseChain = c.jumpFalse();
1875 Assert.check(code.isStatementStart());
1876 if (!c.isFalse()) {
1877 code.resolve(c.trueJumps);
1878 genStat(tree.thenpart, env, CRT_STATEMENT | CRT_FLOW_TARGET);
1879 thenExit = code.branch(goto_);
1880 }
1881 if (elseChain != null) {
1882 code.resolve(elseChain);
1883 if (tree.elsepart != null) {
1884 genStat(tree.elsepart, env,CRT_STATEMENT | CRT_FLOW_TARGET);
1885 }
1886 }
1887 code.resolve(thenExit);
1888 code.endScopes(limit);
1889 Assert.check(code.isStatementStart());
1890 }
1891
1892 public void visitExec(JCExpressionStatement tree) {
1893 // Optimize x++ to ++x and x-- to --x.
2180 nerrs++;
2181 }
2182 int elemcode = Code.arraycode(elemtype);
2183 if (elemcode == 0 || (elemcode == 1 && ndims == 1)) {
2184 code.emitAnewarray(makeRef(pos, elemtype), type);
2185 } else if (elemcode == 1) {
2186 code.emitMultianewarray(ndims, makeRef(pos, type), type);
2187 } else {
2188 code.emitNewarray(elemcode, type);
2189 }
2190 return items.makeStackItem(type);
2191 }
2192
2193 public void visitParens(JCParens tree) {
2194 result = genExpr(tree.expr, tree.expr.type);
2195 }
2196
2197 public void visitAssign(JCAssign tree) {
2198 Item l = genExpr(tree.lhs, tree.lhs.type);
2199 genExpr(tree.rhs, tree.lhs.type).load();
2200 Set<VarSymbol> tmpUnsetSymbols = unsetFieldsInfo.getUnsetFields(env.enclClass.sym, tree);
2201 code.currentUnsetFields = tmpUnsetSymbols != null ? tmpUnsetSymbols : code.currentUnsetFields;
2202 if (tree.rhs.type.hasTag(BOT)) {
2203 /* This is just a case of widening reference conversion that per 5.1.5 simply calls
2204 for "regarding a reference as having some other type in a manner that can be proved
2205 correct at compile time."
2206 */
2207 code.state.forceStackTop(tree.lhs.type);
2208 }
2209 result = items.makeAssignItem(l);
2210 }
2211
2212 public void visitAssignop(JCAssignOp tree) {
2213 OperatorSymbol operator = tree.operator;
2214 Item l;
2215 if (operator.opcode == string_add) {
2216 l = concat.makeConcat(tree);
2217 } else {
2218 // Generate code for first expression
2219 l = genExpr(tree.lhs, tree.lhs.type);
2220
2221 // If we have an increment of -32768 to +32767 of a local
2460 items.makeThisItem().load();
2461 sym = binaryQualifier(sym, env.enclClass.type);
2462 result = items.makeMemberItem(sym, nonVirtualForPrivateAccess(sym));
2463 }
2464 }
2465
2466 //where
2467 private boolean nonVirtualForPrivateAccess(Symbol sym) {
2468 boolean useVirtual = target.hasVirtualPrivateInvoke() &&
2469 !disableVirtualizedPrivateInvoke;
2470 return !useVirtual && ((sym.flags() & PRIVATE) != 0);
2471 }
2472
2473 public void visitSelect(JCFieldAccess tree) {
2474 Symbol sym = tree.sym;
2475
2476 if (tree.name == names._class) {
2477 code.emitLdc((LoadableConstant)checkDimension(tree.pos(), tree.selected.type));
2478 result = items.makeStackItem(pt);
2479 return;
2480 }
2481
2482 Symbol ssym = TreeInfo.symbol(tree.selected);
2483
2484 // Are we selecting via super?
2485 boolean selectSuper =
2486 ssym != null && (ssym.kind == TYP || ssym.name == names._super);
2487
2488 // Are we accessing a member of the superclass in an access method
2489 // resulting from a qualified super?
2490 boolean accessSuper = isAccessSuper(env.enclMethod);
2491
2492 Item base = (selectSuper)
2493 ? items.makeSuperItem()
2494 : genExpr(tree.selected, tree.selected.type);
2495
2496 if (sym.kind == VAR && ((VarSymbol) sym).getConstValue() != null) {
2497 // We are seeing a variable that is constant but its selecting
2498 // expression is not.
2499 if ((sym.flags() & STATIC) != 0) {
2500 if (!selectSuper && (ssym == null || ssym.kind != TYP))
|