Mon, 26 Mar 2012 15:27:51 +0100
7151580: Separate DA/DU logic from exception checking logic in Flow.java
Summary: DA/DU analysis and exception checking analysis should live in two separate tree visitors
Reviewed-by: gafter, dlsmith, jjg
duke@1 | 1 | /* |
mcimadamore@1237 | 2 | * Copyright (c) 1999, 2012, Oracle and/or its affiliates. All rights reserved. |
duke@1 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@1 | 4 | * |
duke@1 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@1 | 6 | * under the terms of the GNU General Public License version 2 only, as |
ohair@554 | 7 | * published by the Free Software Foundation. Oracle designates this |
duke@1 | 8 | * particular file as subject to the "Classpath" exception as provided |
ohair@554 | 9 | * by Oracle in the LICENSE file that accompanied this code. |
duke@1 | 10 | * |
duke@1 | 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@1 | 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@1 | 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@1 | 14 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@1 | 15 | * accompanied this code). |
duke@1 | 16 | * |
duke@1 | 17 | * You should have received a copy of the GNU General Public License version |
duke@1 | 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@1 | 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@1 | 20 | * |
ohair@554 | 21 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
ohair@554 | 22 | * or visit www.oracle.com if you need additional information or have any |
ohair@554 | 23 | * questions. |
duke@1 | 24 | */ |
duke@1 | 25 | |
duke@1 | 26 | //todo: one might eliminate uninits.andSets when monotonic |
duke@1 | 27 | |
duke@1 | 28 | package com.sun.tools.javac.comp; |
duke@1 | 29 | |
mcimadamore@550 | 30 | import java.util.HashMap; |
mcimadamore@550 | 31 | |
duke@1 | 32 | import com.sun.tools.javac.code.*; |
duke@1 | 33 | import com.sun.tools.javac.tree.*; |
duke@1 | 34 | import com.sun.tools.javac.util.*; |
duke@1 | 35 | import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; |
duke@1 | 36 | |
duke@1 | 37 | import com.sun.tools.javac.code.Symbol.*; |
duke@1 | 38 | import com.sun.tools.javac.tree.JCTree.*; |
duke@1 | 39 | |
duke@1 | 40 | import static com.sun.tools.javac.code.Flags.*; |
jjg@1127 | 41 | import static com.sun.tools.javac.code.Flags.BLOCK; |
duke@1 | 42 | import static com.sun.tools.javac.code.Kinds.*; |
duke@1 | 43 | import static com.sun.tools.javac.code.TypeTags.*; |
jjg@1127 | 44 | import static com.sun.tools.javac.tree.JCTree.Tag.*; |
duke@1 | 45 | |
duke@1 | 46 | /** This pass implements dataflow analysis for Java programs. |
duke@1 | 47 | * Liveness analysis checks that every statement is reachable. |
duke@1 | 48 | * Exception analysis ensures that every checked exception that is |
duke@1 | 49 | * thrown is declared or caught. Definite assignment analysis |
duke@1 | 50 | * ensures that each variable is assigned when used. Definite |
duke@1 | 51 | * unassignment analysis ensures that no final variable is assigned |
duke@1 | 52 | * more than once. |
duke@1 | 53 | * |
jjh@972 | 54 | * <p>The JLS has a number of problems in the |
duke@1 | 55 | * specification of these flow analysis problems. This implementation |
duke@1 | 56 | * attempts to address those issues. |
duke@1 | 57 | * |
duke@1 | 58 | * <p>First, there is no accommodation for a finally clause that cannot |
duke@1 | 59 | * complete normally. For liveness analysis, an intervening finally |
duke@1 | 60 | * clause can cause a break, continue, or return not to reach its |
duke@1 | 61 | * target. For exception analysis, an intervening finally clause can |
duke@1 | 62 | * cause any exception to be "caught". For DA/DU analysis, the finally |
duke@1 | 63 | * clause can prevent a transfer of control from propagating DA/DU |
duke@1 | 64 | * state to the target. In addition, code in the finally clause can |
duke@1 | 65 | * affect the DA/DU status of variables. |
duke@1 | 66 | * |
duke@1 | 67 | * <p>For try statements, we introduce the idea of a variable being |
duke@1 | 68 | * definitely unassigned "everywhere" in a block. A variable V is |
duke@1 | 69 | * "unassigned everywhere" in a block iff it is unassigned at the |
duke@1 | 70 | * beginning of the block and there is no reachable assignment to V |
duke@1 | 71 | * in the block. An assignment V=e is reachable iff V is not DA |
duke@1 | 72 | * after e. Then we can say that V is DU at the beginning of the |
duke@1 | 73 | * catch block iff V is DU everywhere in the try block. Similarly, V |
duke@1 | 74 | * is DU at the beginning of the finally block iff V is DU everywhere |
duke@1 | 75 | * in the try block and in every catch block. Specifically, the |
duke@1 | 76 | * following bullet is added to 16.2.2 |
duke@1 | 77 | * <pre> |
duke@1 | 78 | * V is <em>unassigned everywhere</em> in a block if it is |
duke@1 | 79 | * unassigned before the block and there is no reachable |
duke@1 | 80 | * assignment to V within the block. |
duke@1 | 81 | * </pre> |
duke@1 | 82 | * <p>In 16.2.15, the third bullet (and all of its sub-bullets) for all |
duke@1 | 83 | * try blocks is changed to |
duke@1 | 84 | * <pre> |
duke@1 | 85 | * V is definitely unassigned before a catch block iff V is |
duke@1 | 86 | * definitely unassigned everywhere in the try block. |
duke@1 | 87 | * </pre> |
duke@1 | 88 | * <p>The last bullet (and all of its sub-bullets) for try blocks that |
duke@1 | 89 | * have a finally block is changed to |
duke@1 | 90 | * <pre> |
duke@1 | 91 | * V is definitely unassigned before the finally block iff |
duke@1 | 92 | * V is definitely unassigned everywhere in the try block |
duke@1 | 93 | * and everywhere in each catch block of the try statement. |
duke@1 | 94 | * </pre> |
duke@1 | 95 | * <p>In addition, |
duke@1 | 96 | * <pre> |
duke@1 | 97 | * V is definitely assigned at the end of a constructor iff |
duke@1 | 98 | * V is definitely assigned after the block that is the body |
duke@1 | 99 | * of the constructor and V is definitely assigned at every |
duke@1 | 100 | * return that can return from the constructor. |
duke@1 | 101 | * </pre> |
duke@1 | 102 | * <p>In addition, each continue statement with the loop as its target |
duke@1 | 103 | * is treated as a jump to the end of the loop body, and "intervening" |
duke@1 | 104 | * finally clauses are treated as follows: V is DA "due to the |
duke@1 | 105 | * continue" iff V is DA before the continue statement or V is DA at |
duke@1 | 106 | * the end of any intervening finally block. V is DU "due to the |
duke@1 | 107 | * continue" iff any intervening finally cannot complete normally or V |
duke@1 | 108 | * is DU at the end of every intervening finally block. This "due to |
duke@1 | 109 | * the continue" concept is then used in the spec for the loops. |
duke@1 | 110 | * |
duke@1 | 111 | * <p>Similarly, break statements must consider intervening finally |
duke@1 | 112 | * blocks. For liveness analysis, a break statement for which any |
duke@1 | 113 | * intervening finally cannot complete normally is not considered to |
duke@1 | 114 | * cause the target statement to be able to complete normally. Then |
duke@1 | 115 | * we say V is DA "due to the break" iff V is DA before the break or |
duke@1 | 116 | * V is DA at the end of any intervening finally block. V is DU "due |
duke@1 | 117 | * to the break" iff any intervening finally cannot complete normally |
duke@1 | 118 | * or V is DU at the break and at the end of every intervening |
duke@1 | 119 | * finally block. (I suspect this latter condition can be |
duke@1 | 120 | * simplified.) This "due to the break" is then used in the spec for |
duke@1 | 121 | * all statements that can be "broken". |
duke@1 | 122 | * |
duke@1 | 123 | * <p>The return statement is treated similarly. V is DA "due to a |
duke@1 | 124 | * return statement" iff V is DA before the return statement or V is |
duke@1 | 125 | * DA at the end of any intervening finally block. Note that we |
duke@1 | 126 | * don't have to worry about the return expression because this |
duke@1 | 127 | * concept is only used for construcrors. |
duke@1 | 128 | * |
jjh@972 | 129 | * <p>There is no spec in the JLS for when a variable is definitely |
duke@1 | 130 | * assigned at the end of a constructor, which is needed for final |
duke@1 | 131 | * fields (8.3.1.2). We implement the rule that V is DA at the end |
duke@1 | 132 | * of the constructor iff it is DA and the end of the body of the |
duke@1 | 133 | * constructor and V is DA "due to" every return of the constructor. |
duke@1 | 134 | * |
duke@1 | 135 | * <p>Intervening finally blocks similarly affect exception analysis. An |
duke@1 | 136 | * intervening finally that cannot complete normally allows us to ignore |
duke@1 | 137 | * an otherwise uncaught exception. |
duke@1 | 138 | * |
duke@1 | 139 | * <p>To implement the semantics of intervening finally clauses, all |
duke@1 | 140 | * nonlocal transfers (break, continue, return, throw, method call that |
duke@1 | 141 | * can throw a checked exception, and a constructor invocation that can |
duke@1 | 142 | * thrown a checked exception) are recorded in a queue, and removed |
duke@1 | 143 | * from the queue when we complete processing the target of the |
duke@1 | 144 | * nonlocal transfer. This allows us to modify the queue in accordance |
duke@1 | 145 | * with the above rules when we encounter a finally clause. The only |
duke@1 | 146 | * exception to this [no pun intended] is that checked exceptions that |
duke@1 | 147 | * are known to be caught or declared to be caught in the enclosing |
duke@1 | 148 | * method are not recorded in the queue, but instead are recorded in a |
duke@1 | 149 | * global variable "Set<Type> thrown" that records the type of all |
duke@1 | 150 | * exceptions that can be thrown. |
duke@1 | 151 | * |
duke@1 | 152 | * <p>Other minor issues the treatment of members of other classes |
duke@1 | 153 | * (always considered DA except that within an anonymous class |
duke@1 | 154 | * constructor, where DA status from the enclosing scope is |
duke@1 | 155 | * preserved), treatment of the case expression (V is DA before the |
duke@1 | 156 | * case expression iff V is DA after the switch expression), |
duke@1 | 157 | * treatment of variables declared in a switch block (the implied |
duke@1 | 158 | * DA/DU status after the switch expression is DU and not DA for |
duke@1 | 159 | * variables defined in a switch block), the treatment of boolean ?: |
duke@1 | 160 | * expressions (The JLS rules only handle b and c non-boolean; the |
duke@1 | 161 | * new rule is that if b and c are boolean valued, then V is |
duke@1 | 162 | * (un)assigned after a?b:c when true/false iff V is (un)assigned |
duke@1 | 163 | * after b when true/false and V is (un)assigned after c when |
duke@1 | 164 | * true/false). |
duke@1 | 165 | * |
duke@1 | 166 | * <p>There is the remaining question of what syntactic forms constitute a |
duke@1 | 167 | * reference to a variable. It is conventional to allow this.x on the |
duke@1 | 168 | * left-hand-side to initialize a final instance field named x, yet |
duke@1 | 169 | * this.x isn't considered a "use" when appearing on a right-hand-side |
duke@1 | 170 | * in most implementations. Should parentheses affect what is |
duke@1 | 171 | * considered a variable reference? The simplest rule would be to |
duke@1 | 172 | * allow unqualified forms only, parentheses optional, and phase out |
duke@1 | 173 | * support for assigning to a final field via this.x. |
duke@1 | 174 | * |
jjg@581 | 175 | * <p><b>This is NOT part of any supported API. |
jjg@581 | 176 | * If you write code that depends on this, you do so at your own risk. |
duke@1 | 177 | * This code and its internal interfaces are subject to change or |
duke@1 | 178 | * deletion without notice.</b> |
duke@1 | 179 | */ |
mcimadamore@1237 | 180 | public class Flow { |
duke@1 | 181 | protected static final Context.Key<Flow> flowKey = |
duke@1 | 182 | new Context.Key<Flow>(); |
duke@1 | 183 | |
jjg@113 | 184 | private final Names names; |
duke@1 | 185 | private final Log log; |
duke@1 | 186 | private final Symtab syms; |
duke@1 | 187 | private final Types types; |
duke@1 | 188 | private final Check chk; |
duke@1 | 189 | private TreeMaker make; |
mcimadamore@617 | 190 | private final Resolve rs; |
mcimadamore@617 | 191 | private Env<AttrContext> attrEnv; |
duke@1 | 192 | private Lint lint; |
mcimadamore@935 | 193 | private final boolean allowImprovedRethrowAnalysis; |
mcimadamore@935 | 194 | private final boolean allowImprovedCatchAnalysis; |
duke@1 | 195 | |
duke@1 | 196 | public static Flow instance(Context context) { |
duke@1 | 197 | Flow instance = context.get(flowKey); |
duke@1 | 198 | if (instance == null) |
duke@1 | 199 | instance = new Flow(context); |
duke@1 | 200 | return instance; |
duke@1 | 201 | } |
duke@1 | 202 | |
mcimadamore@1237 | 203 | public void analyzeTree(Env<AttrContext> env, TreeMaker make) { |
mcimadamore@1237 | 204 | new FlowAnalyzer().analyzeTree(env, make); |
mcimadamore@1237 | 205 | new AssignAnalyzer().analyzeTree(env, make); |
mcimadamore@1237 | 206 | } |
mcimadamore@1237 | 207 | |
duke@1 | 208 | protected Flow(Context context) { |
duke@1 | 209 | context.put(flowKey, this); |
jjg@113 | 210 | names = Names.instance(context); |
duke@1 | 211 | log = Log.instance(context); |
duke@1 | 212 | syms = Symtab.instance(context); |
duke@1 | 213 | types = Types.instance(context); |
duke@1 | 214 | chk = Check.instance(context); |
duke@1 | 215 | lint = Lint.instance(context); |
mcimadamore@617 | 216 | rs = Resolve.instance(context); |
mcimadamore@550 | 217 | Source source = Source.instance(context); |
mcimadamore@935 | 218 | allowImprovedRethrowAnalysis = source.allowImprovedRethrowAnalysis(); |
mcimadamore@935 | 219 | allowImprovedCatchAnalysis = source.allowImprovedCatchAnalysis(); |
duke@1 | 220 | } |
duke@1 | 221 | |
mcimadamore@1237 | 222 | /** |
mcimadamore@1237 | 223 | * Base visitor class for all visitors implementing dataflow analysis logic. |
mcimadamore@1237 | 224 | * This class define the shared logic for handling jumps (break/continue statements). |
duke@1 | 225 | */ |
mcimadamore@1237 | 226 | static abstract class BaseAnalyzer<P extends BaseAnalyzer.PendingExit> extends TreeScanner { |
duke@1 | 227 | |
mcimadamore@1237 | 228 | enum JumpKind { |
mcimadamore@1237 | 229 | BREAK(JCTree.Tag.BREAK) { |
mcimadamore@1237 | 230 | @Override |
mcimadamore@1237 | 231 | JCTree getTarget(JCTree tree) { |
mcimadamore@1237 | 232 | return ((JCBreak)tree).target; |
mcimadamore@1237 | 233 | } |
mcimadamore@1237 | 234 | }, |
mcimadamore@1237 | 235 | CONTINUE(JCTree.Tag.CONTINUE) { |
mcimadamore@1237 | 236 | @Override |
mcimadamore@1237 | 237 | JCTree getTarget(JCTree tree) { |
mcimadamore@1237 | 238 | return ((JCContinue)tree).target; |
mcimadamore@1237 | 239 | } |
mcimadamore@1237 | 240 | }; |
duke@1 | 241 | |
mcimadamore@1237 | 242 | JCTree.Tag treeTag; |
duke@1 | 243 | |
mcimadamore@1237 | 244 | private JumpKind(Tag treeTag) { |
mcimadamore@1237 | 245 | this.treeTag = treeTag; |
mcimadamore@1237 | 246 | } |
mcimadamore@550 | 247 | |
mcimadamore@1237 | 248 | abstract JCTree getTarget(JCTree tree); |
mcimadamore@1237 | 249 | } |
duke@1 | 250 | |
mcimadamore@1237 | 251 | /** The currently pending exits that go from current inner blocks |
mcimadamore@1237 | 252 | * to an enclosing block, in source order. |
mcimadamore@1237 | 253 | */ |
mcimadamore@1237 | 254 | ListBuffer<P> pendingExits; |
duke@1 | 255 | |
mcimadamore@1237 | 256 | /** A pending exit. These are the statements return, break, and |
mcimadamore@1237 | 257 | * continue. In addition, exception-throwing expressions or |
mcimadamore@1237 | 258 | * statements are put here when not known to be caught. This |
mcimadamore@1237 | 259 | * will typically result in an error unless it is within a |
mcimadamore@1237 | 260 | * try-finally whose finally block cannot complete normally. |
mcimadamore@1237 | 261 | */ |
mcimadamore@1237 | 262 | abstract static class PendingExit { |
mcimadamore@1237 | 263 | JCTree tree; |
duke@1 | 264 | |
mcimadamore@1237 | 265 | PendingExit(JCTree tree) { |
mcimadamore@1237 | 266 | this.tree = tree; |
mcimadamore@1237 | 267 | } |
duke@1 | 268 | |
mcimadamore@1237 | 269 | abstract void resolveJump(); |
mcimadamore@1237 | 270 | } |
duke@1 | 271 | |
mcimadamore@1237 | 272 | abstract void markDead(); |
duke@1 | 273 | |
mcimadamore@1237 | 274 | /** Record an outward transfer of control. */ |
mcimadamore@1237 | 275 | void recordExit(JCTree tree, P pe) { |
mcimadamore@1237 | 276 | pendingExits.append(pe); |
mcimadamore@1237 | 277 | markDead(); |
mcimadamore@1237 | 278 | } |
duke@1 | 279 | |
mcimadamore@1237 | 280 | /** Resolve all jumps of this statement. */ |
mcimadamore@1237 | 281 | private boolean resolveJump(JCTree tree, |
mcimadamore@1237 | 282 | ListBuffer<P> oldPendingExits, |
mcimadamore@1237 | 283 | JumpKind jk) { |
mcimadamore@1237 | 284 | boolean resolved = false; |
mcimadamore@1237 | 285 | List<P> exits = pendingExits.toList(); |
mcimadamore@1237 | 286 | pendingExits = oldPendingExits; |
mcimadamore@1237 | 287 | for (; exits.nonEmpty(); exits = exits.tail) { |
mcimadamore@1237 | 288 | P exit = exits.head; |
mcimadamore@1237 | 289 | if (exit.tree.hasTag(jk.treeTag) && |
mcimadamore@1237 | 290 | jk.getTarget(exit.tree) == tree) { |
mcimadamore@1237 | 291 | exit.resolveJump(); |
mcimadamore@1237 | 292 | resolved = true; |
mcimadamore@1237 | 293 | } else { |
mcimadamore@1237 | 294 | pendingExits.append(exit); |
mcimadamore@1237 | 295 | } |
mcimadamore@1237 | 296 | } |
mcimadamore@1237 | 297 | return resolved; |
mcimadamore@1237 | 298 | } |
duke@1 | 299 | |
mcimadamore@1237 | 300 | /** Resolve all breaks of this statement. */ |
mcimadamore@1237 | 301 | boolean resolveContinues(JCTree tree) { |
mcimadamore@1237 | 302 | return resolveJump(tree, new ListBuffer<P>(), JumpKind.CONTINUE); |
mcimadamore@1237 | 303 | } |
darcy@609 | 304 | |
mcimadamore@1237 | 305 | /** Resolve all continues of this statement. */ |
mcimadamore@1237 | 306 | boolean resolveBreaks(JCTree tree, ListBuffer<P> oldPendingExits) { |
mcimadamore@1237 | 307 | return resolveJump(tree, oldPendingExits, JumpKind.BREAK); |
duke@1 | 308 | } |
duke@1 | 309 | } |
duke@1 | 310 | |
mcimadamore@1237 | 311 | /** |
mcimadamore@1237 | 312 | * This pass implements the first two steps of the dataflow analysis: |
mcimadamore@1237 | 313 | * (i) liveness analysis checks that every statement is reachable and (ii) |
mcimadamore@1237 | 314 | * exception analysis to ensure that every checked exception that is |
mcimadamore@1237 | 315 | * thrown is declared or caught. |
duke@1 | 316 | */ |
mcimadamore@1237 | 317 | class FlowAnalyzer extends BaseAnalyzer<FlowAnalyzer.FlowPendingExit> { |
duke@1 | 318 | |
mcimadamore@1237 | 319 | /** A flag that indicates whether the last statement could |
mcimadamore@1237 | 320 | * complete normally. |
mcimadamore@1237 | 321 | */ |
mcimadamore@1237 | 322 | private boolean alive; |
duke@1 | 323 | |
mcimadamore@1237 | 324 | HashMap<Symbol, List<Type>> preciseRethrowTypes; |
mcimadamore@1237 | 325 | |
mcimadamore@1237 | 326 | /** The current class being defined. |
mcimadamore@1237 | 327 | */ |
mcimadamore@1237 | 328 | JCClassDecl classDef; |
mcimadamore@1237 | 329 | |
mcimadamore@1237 | 330 | /** The list of possibly thrown declarable exceptions. |
mcimadamore@1237 | 331 | */ |
mcimadamore@1237 | 332 | List<Type> thrown; |
mcimadamore@1237 | 333 | |
mcimadamore@1237 | 334 | /** The list of exceptions that are either caught or declared to be |
mcimadamore@1237 | 335 | * thrown. |
mcimadamore@1237 | 336 | */ |
mcimadamore@1237 | 337 | List<Type> caught; |
mcimadamore@1237 | 338 | |
mcimadamore@1237 | 339 | class FlowPendingExit extends BaseAnalyzer.PendingExit { |
mcimadamore@1237 | 340 | |
mcimadamore@1237 | 341 | Type thrown; |
mcimadamore@1237 | 342 | |
mcimadamore@1237 | 343 | FlowPendingExit(JCTree tree, Type thrown) { |
mcimadamore@1237 | 344 | super(tree); |
mcimadamore@1237 | 345 | this.thrown = thrown; |
mcimadamore@1237 | 346 | } |
mcimadamore@1237 | 347 | |
mcimadamore@1237 | 348 | void resolveJump() { /*do nothing*/ } |
mcimadamore@1237 | 349 | } |
mcimadamore@1237 | 350 | |
mcimadamore@1237 | 351 | @Override |
mcimadamore@1237 | 352 | void markDead() { |
mcimadamore@1237 | 353 | alive = false; |
mcimadamore@1237 | 354 | } |
mcimadamore@1237 | 355 | |
mcimadamore@1237 | 356 | /*-------------------- Exceptions ----------------------*/ |
mcimadamore@1237 | 357 | |
mcimadamore@1237 | 358 | /** Complain that pending exceptions are not caught. |
mcimadamore@1237 | 359 | */ |
mcimadamore@1237 | 360 | void errorUncaught() { |
mcimadamore@1237 | 361 | for (FlowPendingExit exit = pendingExits.next(); |
mcimadamore@1237 | 362 | exit != null; |
mcimadamore@1237 | 363 | exit = pendingExits.next()) { |
mcimadamore@1237 | 364 | if (classDef != null && |
mcimadamore@1237 | 365 | classDef.pos == exit.tree.pos) { |
mcimadamore@1237 | 366 | log.error(exit.tree.pos(), |
mcimadamore@1237 | 367 | "unreported.exception.default.constructor", |
mcimadamore@1237 | 368 | exit.thrown); |
mcimadamore@1237 | 369 | } else if (exit.tree.hasTag(VARDEF) && |
mcimadamore@1237 | 370 | ((JCVariableDecl)exit.tree).sym.isResourceVariable()) { |
mcimadamore@1237 | 371 | log.error(exit.tree.pos(), |
mcimadamore@1237 | 372 | "unreported.exception.implicit.close", |
mcimadamore@1237 | 373 | exit.thrown, |
mcimadamore@1237 | 374 | ((JCVariableDecl)exit.tree).sym.name); |
mcimadamore@1237 | 375 | } else { |
mcimadamore@1237 | 376 | log.error(exit.tree.pos(), |
mcimadamore@1237 | 377 | "unreported.exception.need.to.catch.or.throw", |
mcimadamore@1237 | 378 | exit.thrown); |
mcimadamore@1237 | 379 | } |
mcimadamore@1237 | 380 | } |
mcimadamore@1237 | 381 | } |
mcimadamore@1237 | 382 | |
mcimadamore@1237 | 383 | /** Record that exception is potentially thrown and check that it |
mcimadamore@1237 | 384 | * is caught. |
mcimadamore@1237 | 385 | */ |
mcimadamore@1237 | 386 | void markThrown(JCTree tree, Type exc) { |
mcimadamore@1237 | 387 | if (!chk.isUnchecked(tree.pos(), exc)) { |
mcimadamore@1237 | 388 | if (!chk.isHandled(exc, caught)) |
mcimadamore@1237 | 389 | pendingExits.append(new FlowPendingExit(tree, exc)); |
mcimadamore@1237 | 390 | thrown = chk.incl(exc, thrown); |
mcimadamore@1237 | 391 | } |
mcimadamore@1237 | 392 | } |
mcimadamore@1237 | 393 | |
mcimadamore@1237 | 394 | /************************************************************************* |
mcimadamore@1237 | 395 | * Visitor methods for statements and definitions |
mcimadamore@1237 | 396 | *************************************************************************/ |
mcimadamore@1237 | 397 | |
mcimadamore@1237 | 398 | /** Analyze a definition. |
mcimadamore@1237 | 399 | */ |
mcimadamore@1237 | 400 | void scanDef(JCTree tree) { |
mcimadamore@1237 | 401 | scanStat(tree); |
mcimadamore@1237 | 402 | if (tree != null && tree.hasTag(JCTree.Tag.BLOCK) && !alive) { |
mcimadamore@1237 | 403 | log.error(tree.pos(), |
mcimadamore@1237 | 404 | "initializer.must.be.able.to.complete.normally"); |
mcimadamore@1237 | 405 | } |
mcimadamore@1237 | 406 | } |
mcimadamore@1237 | 407 | |
mcimadamore@1237 | 408 | /** Analyze a statement. Check that statement is reachable. |
mcimadamore@1237 | 409 | */ |
mcimadamore@1237 | 410 | void scanStat(JCTree tree) { |
mcimadamore@1237 | 411 | if (!alive && tree != null) { |
mcimadamore@1237 | 412 | log.error(tree.pos(), "unreachable.stmt"); |
mcimadamore@1237 | 413 | if (!tree.hasTag(SKIP)) alive = true; |
mcimadamore@1237 | 414 | } |
mcimadamore@1237 | 415 | scan(tree); |
mcimadamore@1237 | 416 | } |
mcimadamore@1237 | 417 | |
mcimadamore@1237 | 418 | /** Analyze list of statements. |
mcimadamore@1237 | 419 | */ |
mcimadamore@1237 | 420 | void scanStats(List<? extends JCStatement> trees) { |
mcimadamore@1237 | 421 | if (trees != null) |
mcimadamore@1237 | 422 | for (List<? extends JCStatement> l = trees; l.nonEmpty(); l = l.tail) |
mcimadamore@1237 | 423 | scanStat(l.head); |
mcimadamore@1237 | 424 | } |
mcimadamore@1237 | 425 | |
mcimadamore@1237 | 426 | /* ------------ Visitor methods for various sorts of trees -------------*/ |
mcimadamore@1237 | 427 | |
mcimadamore@1237 | 428 | public void visitClassDef(JCClassDecl tree) { |
mcimadamore@1237 | 429 | if (tree.sym == null) return; |
mcimadamore@1237 | 430 | |
mcimadamore@1237 | 431 | JCClassDecl classDefPrev = classDef; |
mcimadamore@1237 | 432 | List<Type> thrownPrev = thrown; |
mcimadamore@1237 | 433 | List<Type> caughtPrev = caught; |
mcimadamore@1237 | 434 | boolean alivePrev = alive; |
mcimadamore@1237 | 435 | ListBuffer<FlowPendingExit> pendingExitsPrev = pendingExits; |
mcimadamore@1237 | 436 | Lint lintPrev = lint; |
mcimadamore@1237 | 437 | |
mcimadamore@1237 | 438 | pendingExits = new ListBuffer<FlowPendingExit>(); |
mcimadamore@1237 | 439 | if (tree.name != names.empty) { |
mcimadamore@1237 | 440 | caught = List.nil(); |
mcimadamore@1237 | 441 | } |
mcimadamore@1237 | 442 | classDef = tree; |
mcimadamore@1237 | 443 | thrown = List.nil(); |
mcimadamore@1237 | 444 | lint = lint.augment(tree.sym.attributes_field); |
mcimadamore@1237 | 445 | |
mcimadamore@1237 | 446 | try { |
mcimadamore@1237 | 447 | // process all the static initializers |
mcimadamore@1237 | 448 | for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 449 | if (!l.head.hasTag(METHODDEF) && |
mcimadamore@1237 | 450 | (TreeInfo.flags(l.head) & STATIC) != 0) { |
mcimadamore@1237 | 451 | scanDef(l.head); |
mcimadamore@1237 | 452 | errorUncaught(); |
mcimadamore@1237 | 453 | } |
mcimadamore@1237 | 454 | } |
mcimadamore@1237 | 455 | |
mcimadamore@1237 | 456 | // add intersection of all thrown clauses of initial constructors |
mcimadamore@1237 | 457 | // to set of caught exceptions, unless class is anonymous. |
mcimadamore@1237 | 458 | if (tree.name != names.empty) { |
mcimadamore@1237 | 459 | boolean firstConstructor = true; |
mcimadamore@1237 | 460 | for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 461 | if (TreeInfo.isInitialConstructor(l.head)) { |
mcimadamore@1237 | 462 | List<Type> mthrown = |
mcimadamore@1237 | 463 | ((JCMethodDecl) l.head).sym.type.getThrownTypes(); |
mcimadamore@1237 | 464 | if (firstConstructor) { |
mcimadamore@1237 | 465 | caught = mthrown; |
mcimadamore@1237 | 466 | firstConstructor = false; |
mcimadamore@1237 | 467 | } else { |
mcimadamore@1237 | 468 | caught = chk.intersect(mthrown, caught); |
mcimadamore@1237 | 469 | } |
mcimadamore@1237 | 470 | } |
mcimadamore@1237 | 471 | } |
mcimadamore@1237 | 472 | } |
mcimadamore@1237 | 473 | |
mcimadamore@1237 | 474 | // process all the instance initializers |
mcimadamore@1237 | 475 | for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 476 | if (!l.head.hasTag(METHODDEF) && |
mcimadamore@1237 | 477 | (TreeInfo.flags(l.head) & STATIC) == 0) { |
mcimadamore@1237 | 478 | scanDef(l.head); |
mcimadamore@1237 | 479 | errorUncaught(); |
mcimadamore@1237 | 480 | } |
mcimadamore@1237 | 481 | } |
mcimadamore@1237 | 482 | |
mcimadamore@1237 | 483 | // in an anonymous class, add the set of thrown exceptions to |
mcimadamore@1237 | 484 | // the throws clause of the synthetic constructor and propagate |
mcimadamore@1237 | 485 | // outwards. |
mcimadamore@1237 | 486 | // Changing the throws clause on the fly is okay here because |
mcimadamore@1237 | 487 | // the anonymous constructor can't be invoked anywhere else, |
mcimadamore@1237 | 488 | // and its type hasn't been cached. |
mcimadamore@1237 | 489 | if (tree.name == names.empty) { |
mcimadamore@1237 | 490 | for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 491 | if (TreeInfo.isInitialConstructor(l.head)) { |
mcimadamore@1237 | 492 | JCMethodDecl mdef = (JCMethodDecl)l.head; |
mcimadamore@1237 | 493 | mdef.thrown = make.Types(thrown); |
mcimadamore@1237 | 494 | mdef.sym.type = types.createMethodTypeWithThrown(mdef.sym.type, thrown); |
mcimadamore@1237 | 495 | } |
mcimadamore@1237 | 496 | } |
mcimadamore@1237 | 497 | thrownPrev = chk.union(thrown, thrownPrev); |
mcimadamore@1237 | 498 | } |
mcimadamore@1237 | 499 | |
mcimadamore@1237 | 500 | // process all the methods |
mcimadamore@1237 | 501 | for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 502 | if (l.head.hasTag(METHODDEF)) { |
mcimadamore@1237 | 503 | scan(l.head); |
mcimadamore@1237 | 504 | errorUncaught(); |
mcimadamore@1237 | 505 | } |
mcimadamore@1237 | 506 | } |
mcimadamore@1237 | 507 | |
mcimadamore@1237 | 508 | thrown = thrownPrev; |
mcimadamore@1237 | 509 | } finally { |
mcimadamore@1237 | 510 | pendingExits = pendingExitsPrev; |
mcimadamore@1237 | 511 | alive = alivePrev; |
mcimadamore@1237 | 512 | caught = caughtPrev; |
mcimadamore@1237 | 513 | classDef = classDefPrev; |
mcimadamore@1237 | 514 | lint = lintPrev; |
mcimadamore@1237 | 515 | } |
mcimadamore@1237 | 516 | } |
mcimadamore@1237 | 517 | |
mcimadamore@1237 | 518 | public void visitMethodDef(JCMethodDecl tree) { |
mcimadamore@1237 | 519 | if (tree.body == null) return; |
mcimadamore@1237 | 520 | |
mcimadamore@1237 | 521 | List<Type> caughtPrev = caught; |
mcimadamore@1237 | 522 | List<Type> mthrown = tree.sym.type.getThrownTypes(); |
mcimadamore@1237 | 523 | Lint lintPrev = lint; |
mcimadamore@1237 | 524 | |
mcimadamore@1237 | 525 | lint = lint.augment(tree.sym.attributes_field); |
mcimadamore@1237 | 526 | |
mcimadamore@1237 | 527 | Assert.check(pendingExits.isEmpty()); |
mcimadamore@1237 | 528 | |
mcimadamore@1237 | 529 | try { |
mcimadamore@1237 | 530 | for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 531 | JCVariableDecl def = l.head; |
mcimadamore@1237 | 532 | scan(def); |
mcimadamore@1237 | 533 | } |
mcimadamore@1237 | 534 | if (TreeInfo.isInitialConstructor(tree)) |
mcimadamore@1237 | 535 | caught = chk.union(caught, mthrown); |
mcimadamore@1237 | 536 | else if ((tree.sym.flags() & (BLOCK | STATIC)) != BLOCK) |
mcimadamore@1237 | 537 | caught = mthrown; |
mcimadamore@1237 | 538 | // else we are in an instance initializer block; |
mcimadamore@1237 | 539 | // leave caught unchanged. |
mcimadamore@1237 | 540 | |
mcimadamore@1237 | 541 | alive = true; |
mcimadamore@1237 | 542 | scanStat(tree.body); |
mcimadamore@1237 | 543 | |
mcimadamore@1237 | 544 | if (alive && tree.sym.type.getReturnType().tag != VOID) |
mcimadamore@1237 | 545 | log.error(TreeInfo.diagEndPos(tree.body), "missing.ret.stmt"); |
mcimadamore@1237 | 546 | |
mcimadamore@1237 | 547 | List<FlowPendingExit> exits = pendingExits.toList(); |
mcimadamore@1237 | 548 | pendingExits = new ListBuffer<FlowPendingExit>(); |
mcimadamore@1237 | 549 | while (exits.nonEmpty()) { |
mcimadamore@1237 | 550 | FlowPendingExit exit = exits.head; |
mcimadamore@1237 | 551 | exits = exits.tail; |
mcimadamore@1237 | 552 | if (exit.thrown == null) { |
mcimadamore@1237 | 553 | Assert.check(exit.tree.hasTag(RETURN)); |
mcimadamore@1237 | 554 | } else { |
mcimadamore@1237 | 555 | // uncaught throws will be reported later |
mcimadamore@1237 | 556 | pendingExits.append(exit); |
mcimadamore@1237 | 557 | } |
mcimadamore@1237 | 558 | } |
mcimadamore@1237 | 559 | } finally { |
mcimadamore@1237 | 560 | caught = caughtPrev; |
mcimadamore@1237 | 561 | lint = lintPrev; |
mcimadamore@1237 | 562 | } |
mcimadamore@1237 | 563 | } |
mcimadamore@1237 | 564 | |
mcimadamore@1237 | 565 | public void visitVarDef(JCVariableDecl tree) { |
mcimadamore@1237 | 566 | if (tree.init != null) { |
mcimadamore@1237 | 567 | Lint lintPrev = lint; |
mcimadamore@1237 | 568 | lint = lint.augment(tree.sym.attributes_field); |
mcimadamore@1237 | 569 | try{ |
mcimadamore@1237 | 570 | scan(tree.init); |
mcimadamore@1237 | 571 | } finally { |
mcimadamore@1237 | 572 | lint = lintPrev; |
mcimadamore@1237 | 573 | } |
mcimadamore@1237 | 574 | } |
mcimadamore@1237 | 575 | } |
mcimadamore@1237 | 576 | |
mcimadamore@1237 | 577 | public void visitBlock(JCBlock tree) { |
mcimadamore@1237 | 578 | scanStats(tree.stats); |
mcimadamore@1237 | 579 | } |
mcimadamore@1237 | 580 | |
mcimadamore@1237 | 581 | public void visitDoLoop(JCDoWhileLoop tree) { |
mcimadamore@1237 | 582 | ListBuffer<FlowPendingExit> prevPendingExits = pendingExits; |
mcimadamore@1237 | 583 | pendingExits = new ListBuffer<FlowPendingExit>(); |
mcimadamore@1237 | 584 | scanStat(tree.body); |
mcimadamore@1237 | 585 | alive |= resolveContinues(tree); |
mcimadamore@1237 | 586 | scan(tree.cond); |
mcimadamore@1237 | 587 | alive = alive && !tree.cond.type.isTrue(); |
mcimadamore@1237 | 588 | alive |= resolveBreaks(tree, prevPendingExits); |
mcimadamore@1237 | 589 | } |
mcimadamore@1237 | 590 | |
mcimadamore@1237 | 591 | public void visitWhileLoop(JCWhileLoop tree) { |
mcimadamore@1237 | 592 | ListBuffer<FlowPendingExit> prevPendingExits = pendingExits; |
mcimadamore@1237 | 593 | pendingExits = new ListBuffer<FlowPendingExit>(); |
mcimadamore@1237 | 594 | scan(tree.cond); |
mcimadamore@1237 | 595 | alive = !tree.cond.type.isFalse(); |
mcimadamore@1237 | 596 | scanStat(tree.body); |
mcimadamore@1237 | 597 | alive |= resolveContinues(tree); |
mcimadamore@1237 | 598 | alive = resolveBreaks(tree, prevPendingExits) || |
mcimadamore@1237 | 599 | !tree.cond.type.isTrue(); |
mcimadamore@1237 | 600 | } |
mcimadamore@1237 | 601 | |
mcimadamore@1237 | 602 | public void visitForLoop(JCForLoop tree) { |
mcimadamore@1237 | 603 | ListBuffer<FlowPendingExit> prevPendingExits = pendingExits; |
mcimadamore@1237 | 604 | scanStats(tree.init); |
mcimadamore@1237 | 605 | pendingExits = new ListBuffer<FlowPendingExit>(); |
mcimadamore@1237 | 606 | if (tree.cond != null) { |
mcimadamore@1237 | 607 | scan(tree.cond); |
mcimadamore@1237 | 608 | alive = !tree.cond.type.isFalse(); |
mcimadamore@878 | 609 | } else { |
mcimadamore@1237 | 610 | alive = true; |
mcimadamore@1237 | 611 | } |
mcimadamore@1237 | 612 | scanStat(tree.body); |
mcimadamore@1237 | 613 | alive |= resolveContinues(tree); |
mcimadamore@1237 | 614 | scan(tree.step); |
mcimadamore@1237 | 615 | alive = resolveBreaks(tree, prevPendingExits) || |
mcimadamore@1237 | 616 | tree.cond != null && !tree.cond.type.isTrue(); |
mcimadamore@1237 | 617 | } |
mcimadamore@1237 | 618 | |
mcimadamore@1237 | 619 | public void visitForeachLoop(JCEnhancedForLoop tree) { |
mcimadamore@1237 | 620 | visitVarDef(tree.var); |
mcimadamore@1237 | 621 | ListBuffer<FlowPendingExit> prevPendingExits = pendingExits; |
mcimadamore@1237 | 622 | scan(tree.expr); |
mcimadamore@1237 | 623 | pendingExits = new ListBuffer<FlowPendingExit>(); |
mcimadamore@1237 | 624 | scanStat(tree.body); |
mcimadamore@1237 | 625 | alive |= resolveContinues(tree); |
mcimadamore@1237 | 626 | resolveBreaks(tree, prevPendingExits); |
mcimadamore@1237 | 627 | alive = true; |
mcimadamore@1237 | 628 | } |
mcimadamore@1237 | 629 | |
mcimadamore@1237 | 630 | public void visitLabelled(JCLabeledStatement tree) { |
mcimadamore@1237 | 631 | ListBuffer<FlowPendingExit> prevPendingExits = pendingExits; |
mcimadamore@1237 | 632 | pendingExits = new ListBuffer<FlowPendingExit>(); |
mcimadamore@1237 | 633 | scanStat(tree.body); |
mcimadamore@1237 | 634 | alive |= resolveBreaks(tree, prevPendingExits); |
mcimadamore@1237 | 635 | } |
mcimadamore@1237 | 636 | |
mcimadamore@1237 | 637 | public void visitSwitch(JCSwitch tree) { |
mcimadamore@1237 | 638 | ListBuffer<FlowPendingExit> prevPendingExits = pendingExits; |
mcimadamore@1237 | 639 | pendingExits = new ListBuffer<FlowPendingExit>(); |
mcimadamore@1237 | 640 | scan(tree.selector); |
mcimadamore@1237 | 641 | boolean hasDefault = false; |
mcimadamore@1237 | 642 | for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 643 | alive = true; |
mcimadamore@1237 | 644 | JCCase c = l.head; |
mcimadamore@1237 | 645 | if (c.pat == null) |
mcimadamore@1237 | 646 | hasDefault = true; |
mcimadamore@1237 | 647 | else |
mcimadamore@1237 | 648 | scan(c.pat); |
mcimadamore@1237 | 649 | scanStats(c.stats); |
mcimadamore@1237 | 650 | // Warn about fall-through if lint switch fallthrough enabled. |
mcimadamore@1237 | 651 | if (alive && |
mcimadamore@1237 | 652 | lint.isEnabled(Lint.LintCategory.FALLTHROUGH) && |
mcimadamore@1237 | 653 | c.stats.nonEmpty() && l.tail.nonEmpty()) |
mcimadamore@1237 | 654 | log.warning(Lint.LintCategory.FALLTHROUGH, |
mcimadamore@1237 | 655 | l.tail.head.pos(), |
mcimadamore@1237 | 656 | "possible.fall-through.into.case"); |
mcimadamore@1237 | 657 | } |
mcimadamore@1237 | 658 | if (!hasDefault) { |
mcimadamore@1237 | 659 | alive = true; |
mcimadamore@1237 | 660 | } |
mcimadamore@1237 | 661 | alive |= resolveBreaks(tree, prevPendingExits); |
mcimadamore@1237 | 662 | } |
mcimadamore@1237 | 663 | |
mcimadamore@1237 | 664 | public void visitTry(JCTry tree) { |
mcimadamore@1237 | 665 | List<Type> caughtPrev = caught; |
mcimadamore@1237 | 666 | List<Type> thrownPrev = thrown; |
mcimadamore@1237 | 667 | thrown = List.nil(); |
mcimadamore@1237 | 668 | for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 669 | List<JCExpression> subClauses = TreeInfo.isMultiCatch(l.head) ? |
mcimadamore@1237 | 670 | ((JCTypeUnion)l.head.param.vartype).alternatives : |
mcimadamore@1237 | 671 | List.of(l.head.param.vartype); |
mcimadamore@1237 | 672 | for (JCExpression ct : subClauses) { |
mcimadamore@1237 | 673 | caught = chk.incl(ct.type, caught); |
mcimadamore@1237 | 674 | } |
mcimadamore@1237 | 675 | } |
mcimadamore@1237 | 676 | |
mcimadamore@1237 | 677 | ListBuffer<FlowPendingExit> prevPendingExits = pendingExits; |
mcimadamore@1237 | 678 | pendingExits = new ListBuffer<FlowPendingExit>(); |
mcimadamore@1237 | 679 | for (JCTree resource : tree.resources) { |
mcimadamore@1237 | 680 | if (resource instanceof JCVariableDecl) { |
mcimadamore@1237 | 681 | JCVariableDecl vdecl = (JCVariableDecl) resource; |
mcimadamore@1237 | 682 | visitVarDef(vdecl); |
mcimadamore@1237 | 683 | } else if (resource instanceof JCExpression) { |
mcimadamore@1237 | 684 | scan((JCExpression) resource); |
mcimadamore@1237 | 685 | } else { |
mcimadamore@1237 | 686 | throw new AssertionError(tree); // parser error |
mcimadamore@1237 | 687 | } |
mcimadamore@1237 | 688 | } |
mcimadamore@1237 | 689 | for (JCTree resource : tree.resources) { |
mcimadamore@1237 | 690 | List<Type> closeableSupertypes = resource.type.isCompound() ? |
mcimadamore@1237 | 691 | types.interfaces(resource.type).prepend(types.supertype(resource.type)) : |
mcimadamore@1237 | 692 | List.of(resource.type); |
mcimadamore@1237 | 693 | for (Type sup : closeableSupertypes) { |
mcimadamore@1237 | 694 | if (types.asSuper(sup, syms.autoCloseableType.tsym) != null) { |
mcimadamore@1237 | 695 | Symbol closeMethod = rs.resolveQualifiedMethod(tree, |
mcimadamore@1237 | 696 | attrEnv, |
mcimadamore@1237 | 697 | sup, |
mcimadamore@1237 | 698 | names.close, |
mcimadamore@1237 | 699 | List.<Type>nil(), |
mcimadamore@1237 | 700 | List.<Type>nil()); |
mcimadamore@1237 | 701 | if (closeMethod.kind == MTH) { |
mcimadamore@1237 | 702 | for (Type t : ((MethodSymbol)closeMethod).getThrownTypes()) { |
mcimadamore@1237 | 703 | markThrown(resource, t); |
mcimadamore@1237 | 704 | } |
mcimadamore@1237 | 705 | } |
mcimadamore@1237 | 706 | } |
mcimadamore@1237 | 707 | } |
mcimadamore@1237 | 708 | } |
mcimadamore@1237 | 709 | scanStat(tree.body); |
mcimadamore@1237 | 710 | List<Type> thrownInTry = allowImprovedCatchAnalysis ? |
mcimadamore@1237 | 711 | chk.union(thrown, List.of(syms.runtimeExceptionType, syms.errorType)) : |
mcimadamore@1237 | 712 | thrown; |
mcimadamore@1237 | 713 | thrown = thrownPrev; |
mcimadamore@1237 | 714 | caught = caughtPrev; |
mcimadamore@1237 | 715 | boolean aliveEnd = alive; |
mcimadamore@1237 | 716 | |
mcimadamore@1237 | 717 | List<Type> caughtInTry = List.nil(); |
mcimadamore@1237 | 718 | for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 719 | alive = true; |
mcimadamore@1237 | 720 | JCVariableDecl param = l.head.param; |
mcimadamore@1237 | 721 | List<JCExpression> subClauses = TreeInfo.isMultiCatch(l.head) ? |
mcimadamore@1237 | 722 | ((JCTypeUnion)l.head.param.vartype).alternatives : |
mcimadamore@1237 | 723 | List.of(l.head.param.vartype); |
mcimadamore@1237 | 724 | List<Type> ctypes = List.nil(); |
mcimadamore@1237 | 725 | List<Type> rethrownTypes = chk.diff(thrownInTry, caughtInTry); |
mcimadamore@1237 | 726 | for (JCExpression ct : subClauses) { |
mcimadamore@1237 | 727 | Type exc = ct.type; |
mcimadamore@1237 | 728 | if (exc != syms.unknownType) { |
mcimadamore@1237 | 729 | ctypes = ctypes.append(exc); |
mcimadamore@1237 | 730 | if (types.isSameType(exc, syms.objectType)) |
mcimadamore@1237 | 731 | continue; |
mcimadamore@1237 | 732 | checkCaughtType(l.head.pos(), exc, thrownInTry, caughtInTry); |
mcimadamore@1237 | 733 | caughtInTry = chk.incl(exc, caughtInTry); |
mcimadamore@1237 | 734 | } |
mcimadamore@1237 | 735 | } |
mcimadamore@1237 | 736 | scan(param); |
mcimadamore@1237 | 737 | preciseRethrowTypes.put(param.sym, chk.intersect(ctypes, rethrownTypes)); |
mcimadamore@1237 | 738 | scanStat(l.head.body); |
mcimadamore@1237 | 739 | preciseRethrowTypes.remove(param.sym); |
mcimadamore@1237 | 740 | aliveEnd |= alive; |
mcimadamore@1237 | 741 | } |
mcimadamore@1237 | 742 | if (tree.finalizer != null) { |
mcimadamore@1237 | 743 | List<Type> savedThrown = thrown; |
mcimadamore@1237 | 744 | thrown = List.nil(); |
mcimadamore@1237 | 745 | ListBuffer<FlowPendingExit> exits = pendingExits; |
mcimadamore@1237 | 746 | pendingExits = prevPendingExits; |
mcimadamore@1237 | 747 | alive = true; |
mcimadamore@1237 | 748 | scanStat(tree.finalizer); |
mcimadamore@1237 | 749 | if (!alive) { |
mcimadamore@1237 | 750 | // discard exits and exceptions from try and finally |
mcimadamore@1237 | 751 | thrown = chk.union(thrown, thrownPrev); |
mcimadamore@1237 | 752 | if (lint.isEnabled(Lint.LintCategory.FINALLY)) { |
mcimadamore@1237 | 753 | log.warning(Lint.LintCategory.FINALLY, |
mcimadamore@1237 | 754 | TreeInfo.diagEndPos(tree.finalizer), |
mcimadamore@1237 | 755 | "finally.cannot.complete"); |
mcimadamore@1237 | 756 | } |
mcimadamore@1237 | 757 | } else { |
mcimadamore@1237 | 758 | thrown = chk.union(thrown, chk.diff(thrownInTry, caughtInTry)); |
mcimadamore@1237 | 759 | thrown = chk.union(thrown, savedThrown); |
mcimadamore@1237 | 760 | // FIX: this doesn't preserve source order of exits in catch |
mcimadamore@1237 | 761 | // versus finally! |
mcimadamore@1237 | 762 | while (exits.nonEmpty()) { |
mcimadamore@1237 | 763 | pendingExits.append(exits.next()); |
mcimadamore@1237 | 764 | } |
mcimadamore@1237 | 765 | alive = aliveEnd; |
mcimadamore@1237 | 766 | } |
mcimadamore@1237 | 767 | tree.finallyCanCompleteNormally = alive; |
mcimadamore@1237 | 768 | } else { |
mcimadamore@1237 | 769 | thrown = chk.union(thrown, chk.diff(thrownInTry, caughtInTry)); |
mcimadamore@1237 | 770 | alive = aliveEnd; |
mcimadamore@1237 | 771 | ListBuffer<FlowPendingExit> exits = pendingExits; |
mcimadamore@1237 | 772 | pendingExits = prevPendingExits; |
mcimadamore@1237 | 773 | while (exits.nonEmpty()) pendingExits.append(exits.next()); |
mcimadamore@1237 | 774 | } |
mcimadamore@1237 | 775 | } |
mcimadamore@1237 | 776 | |
mcimadamore@1237 | 777 | @Override |
mcimadamore@1237 | 778 | public void visitIf(JCIf tree) { |
mcimadamore@1237 | 779 | scan(tree.cond); |
mcimadamore@1237 | 780 | scanStat(tree.thenpart); |
mcimadamore@1237 | 781 | if (tree.elsepart != null) { |
mcimadamore@1237 | 782 | boolean aliveAfterThen = alive; |
mcimadamore@1237 | 783 | alive = true; |
mcimadamore@1237 | 784 | scanStat(tree.elsepart); |
mcimadamore@1237 | 785 | alive = alive | aliveAfterThen; |
mcimadamore@1237 | 786 | } else { |
mcimadamore@1237 | 787 | alive = true; |
mcimadamore@1237 | 788 | } |
mcimadamore@1237 | 789 | } |
mcimadamore@1237 | 790 | |
mcimadamore@1237 | 791 | void checkCaughtType(DiagnosticPosition pos, Type exc, List<Type> thrownInTry, List<Type> caughtInTry) { |
mcimadamore@1237 | 792 | if (chk.subset(exc, caughtInTry)) { |
mcimadamore@1237 | 793 | log.error(pos, "except.already.caught", exc); |
mcimadamore@1237 | 794 | } else if (!chk.isUnchecked(pos, exc) && |
mcimadamore@1237 | 795 | !isExceptionOrThrowable(exc) && |
mcimadamore@1237 | 796 | !chk.intersects(exc, thrownInTry)) { |
mcimadamore@1237 | 797 | log.error(pos, "except.never.thrown.in.try", exc); |
mcimadamore@1237 | 798 | } else if (allowImprovedCatchAnalysis) { |
mcimadamore@1237 | 799 | List<Type> catchableThrownTypes = chk.intersect(List.of(exc), thrownInTry); |
mcimadamore@1237 | 800 | // 'catchableThrownTypes' cannnot possibly be empty - if 'exc' was an |
mcimadamore@1237 | 801 | // unchecked exception, the result list would not be empty, as the augmented |
mcimadamore@1237 | 802 | // thrown set includes { RuntimeException, Error }; if 'exc' was a checked |
mcimadamore@1237 | 803 | // exception, that would have been covered in the branch above |
mcimadamore@1237 | 804 | if (chk.diff(catchableThrownTypes, caughtInTry).isEmpty() && |
mcimadamore@1237 | 805 | !isExceptionOrThrowable(exc)) { |
mcimadamore@1237 | 806 | String key = catchableThrownTypes.length() == 1 ? |
mcimadamore@1237 | 807 | "unreachable.catch" : |
mcimadamore@1237 | 808 | "unreachable.catch.1"; |
mcimadamore@1237 | 809 | log.warning(pos, key, catchableThrownTypes); |
mcimadamore@1237 | 810 | } |
mcimadamore@1237 | 811 | } |
mcimadamore@1237 | 812 | } |
mcimadamore@1237 | 813 | //where |
mcimadamore@1237 | 814 | private boolean isExceptionOrThrowable(Type exc) { |
mcimadamore@1237 | 815 | return exc.tsym == syms.throwableType.tsym || |
mcimadamore@1237 | 816 | exc.tsym == syms.exceptionType.tsym; |
mcimadamore@1237 | 817 | } |
mcimadamore@1237 | 818 | |
mcimadamore@1237 | 819 | public void visitBreak(JCBreak tree) { |
mcimadamore@1237 | 820 | recordExit(tree, new FlowPendingExit(tree, null)); |
mcimadamore@1237 | 821 | } |
mcimadamore@1237 | 822 | |
mcimadamore@1237 | 823 | public void visitContinue(JCContinue tree) { |
mcimadamore@1237 | 824 | recordExit(tree, new FlowPendingExit(tree, null)); |
mcimadamore@1237 | 825 | } |
mcimadamore@1237 | 826 | |
mcimadamore@1237 | 827 | public void visitReturn(JCReturn tree) { |
mcimadamore@1237 | 828 | scan(tree.expr); |
mcimadamore@1237 | 829 | // if not initial constructor, should markDead instead of recordExit |
mcimadamore@1237 | 830 | recordExit(tree, new FlowPendingExit(tree, null)); |
mcimadamore@1237 | 831 | } |
mcimadamore@1237 | 832 | |
mcimadamore@1237 | 833 | public void visitThrow(JCThrow tree) { |
mcimadamore@1237 | 834 | scan(tree.expr); |
mcimadamore@1237 | 835 | Symbol sym = TreeInfo.symbol(tree.expr); |
mcimadamore@1237 | 836 | if (sym != null && |
mcimadamore@1237 | 837 | sym.kind == VAR && |
mcimadamore@1237 | 838 | (sym.flags() & (FINAL | EFFECTIVELY_FINAL)) != 0 && |
mcimadamore@1237 | 839 | preciseRethrowTypes.get(sym) != null && |
mcimadamore@1237 | 840 | allowImprovedRethrowAnalysis) { |
mcimadamore@1237 | 841 | for (Type t : preciseRethrowTypes.get(sym)) { |
mcimadamore@1237 | 842 | markThrown(tree, t); |
mcimadamore@1237 | 843 | } |
mcimadamore@1237 | 844 | } |
mcimadamore@1237 | 845 | else { |
mcimadamore@1237 | 846 | markThrown(tree, tree.expr.type); |
mcimadamore@1237 | 847 | } |
mcimadamore@1237 | 848 | markDead(); |
mcimadamore@1237 | 849 | } |
mcimadamore@1237 | 850 | |
mcimadamore@1237 | 851 | public void visitApply(JCMethodInvocation tree) { |
mcimadamore@1237 | 852 | scan(tree.meth); |
mcimadamore@1237 | 853 | scan(tree.args); |
mcimadamore@1237 | 854 | for (List<Type> l = tree.meth.type.getThrownTypes(); l.nonEmpty(); l = l.tail) |
mcimadamore@1237 | 855 | markThrown(tree, l.head); |
mcimadamore@1237 | 856 | } |
mcimadamore@1237 | 857 | |
mcimadamore@1237 | 858 | public void visitNewClass(JCNewClass tree) { |
mcimadamore@1237 | 859 | scan(tree.encl); |
mcimadamore@1237 | 860 | scan(tree.args); |
mcimadamore@1237 | 861 | // scan(tree.def); |
mcimadamore@1237 | 862 | for (List<Type> l = tree.constructorType.getThrownTypes(); |
mcimadamore@1237 | 863 | l.nonEmpty(); |
mcimadamore@1237 | 864 | l = l.tail) { |
mcimadamore@1237 | 865 | markThrown(tree, l.head); |
mcimadamore@1237 | 866 | } |
mcimadamore@1237 | 867 | List<Type> caughtPrev = caught; |
mcimadamore@1237 | 868 | try { |
mcimadamore@1237 | 869 | // If the new class expression defines an anonymous class, |
mcimadamore@1237 | 870 | // analysis of the anonymous constructor may encounter thrown |
mcimadamore@1237 | 871 | // types which are unsubstituted type variables. |
mcimadamore@1237 | 872 | // However, since the constructor's actual thrown types have |
mcimadamore@1237 | 873 | // already been marked as thrown, it is safe to simply include |
mcimadamore@1237 | 874 | // each of the constructor's formal thrown types in the set of |
mcimadamore@1237 | 875 | // 'caught/declared to be thrown' types, for the duration of |
mcimadamore@1237 | 876 | // the class def analysis. |
mcimadamore@1237 | 877 | if (tree.def != null) |
mcimadamore@1237 | 878 | for (List<Type> l = tree.constructor.type.getThrownTypes(); |
mcimadamore@1237 | 879 | l.nonEmpty(); |
mcimadamore@1237 | 880 | l = l.tail) { |
mcimadamore@1237 | 881 | caught = chk.incl(l.head, caught); |
mcimadamore@1237 | 882 | } |
mcimadamore@1237 | 883 | scan(tree.def); |
mcimadamore@1237 | 884 | } |
mcimadamore@1237 | 885 | finally { |
mcimadamore@1237 | 886 | caught = caughtPrev; |
mcimadamore@1237 | 887 | } |
mcimadamore@1237 | 888 | } |
mcimadamore@1237 | 889 | |
mcimadamore@1237 | 890 | public void visitTopLevel(JCCompilationUnit tree) { |
mcimadamore@1237 | 891 | // Do nothing for TopLevel since each class is visited individually |
mcimadamore@1237 | 892 | } |
mcimadamore@1237 | 893 | |
mcimadamore@1237 | 894 | /************************************************************************** |
mcimadamore@1237 | 895 | * main method |
mcimadamore@1237 | 896 | *************************************************************************/ |
mcimadamore@1237 | 897 | |
mcimadamore@1237 | 898 | /** Perform definite assignment/unassignment analysis on a tree. |
mcimadamore@1237 | 899 | */ |
mcimadamore@1237 | 900 | public void analyzeTree(Env<AttrContext> env, TreeMaker make) { |
mcimadamore@1237 | 901 | try { |
mcimadamore@1237 | 902 | attrEnv = env; |
mcimadamore@1237 | 903 | JCTree tree = env.tree; |
mcimadamore@1237 | 904 | Flow.this.make = make; |
mcimadamore@1237 | 905 | pendingExits = new ListBuffer<FlowPendingExit>(); |
mcimadamore@1237 | 906 | preciseRethrowTypes = new HashMap<Symbol, List<Type>>(); |
mcimadamore@1237 | 907 | alive = true; |
mcimadamore@1237 | 908 | this.thrown = this.caught = null; |
mcimadamore@1237 | 909 | this.classDef = null; |
mcimadamore@1237 | 910 | scan(tree); |
mcimadamore@1237 | 911 | } finally { |
mcimadamore@1237 | 912 | pendingExits = null; |
mcimadamore@1237 | 913 | Flow.this.make = null; |
mcimadamore@1237 | 914 | this.thrown = this.caught = null; |
mcimadamore@1237 | 915 | this.classDef = null; |
mcimadamore@878 | 916 | } |
duke@1 | 917 | } |
duke@1 | 918 | } |
duke@1 | 919 | |
mcimadamore@1237 | 920 | /** |
mcimadamore@1237 | 921 | * This pass implements (i) definite assignment analysis, which ensures that |
mcimadamore@1237 | 922 | * each variable is assigned when used and (ii) definite unassignment analysis, |
mcimadamore@1237 | 923 | * which ensures that no final variable is assigned more than once. This visitor |
mcimadamore@1237 | 924 | * depends on the results of the liveliness analyzer. |
duke@1 | 925 | */ |
mcimadamore@1237 | 926 | class AssignAnalyzer extends BaseAnalyzer<AssignAnalyzer.AssignPendingExit> { |
mcimadamore@1237 | 927 | |
mcimadamore@1237 | 928 | /** The set of definitely assigned variables. |
mcimadamore@1237 | 929 | */ |
mcimadamore@1237 | 930 | Bits inits; |
mcimadamore@1237 | 931 | |
mcimadamore@1237 | 932 | /** The set of definitely unassigned variables. |
mcimadamore@1237 | 933 | */ |
mcimadamore@1237 | 934 | Bits uninits; |
mcimadamore@1237 | 935 | |
mcimadamore@1237 | 936 | /** The set of variables that are definitely unassigned everywhere |
mcimadamore@1237 | 937 | * in current try block. This variable is maintained lazily; it is |
mcimadamore@1237 | 938 | * updated only when something gets removed from uninits, |
mcimadamore@1237 | 939 | * typically by being assigned in reachable code. To obtain the |
mcimadamore@1237 | 940 | * correct set of variables which are definitely unassigned |
mcimadamore@1237 | 941 | * anywhere in current try block, intersect uninitsTry and |
mcimadamore@1237 | 942 | * uninits. |
mcimadamore@1237 | 943 | */ |
mcimadamore@1237 | 944 | Bits uninitsTry; |
mcimadamore@1237 | 945 | |
mcimadamore@1237 | 946 | /** When analyzing a condition, inits and uninits are null. |
mcimadamore@1237 | 947 | * Instead we have: |
mcimadamore@1237 | 948 | */ |
mcimadamore@1237 | 949 | Bits initsWhenTrue; |
mcimadamore@1237 | 950 | Bits initsWhenFalse; |
mcimadamore@1237 | 951 | Bits uninitsWhenTrue; |
mcimadamore@1237 | 952 | Bits uninitsWhenFalse; |
mcimadamore@1237 | 953 | |
mcimadamore@1237 | 954 | /** A mapping from addresses to variable symbols. |
mcimadamore@1237 | 955 | */ |
mcimadamore@1237 | 956 | VarSymbol[] vars; |
mcimadamore@1237 | 957 | |
mcimadamore@1237 | 958 | /** The current class being defined. |
mcimadamore@1237 | 959 | */ |
mcimadamore@1237 | 960 | JCClassDecl classDef; |
mcimadamore@1237 | 961 | |
mcimadamore@1237 | 962 | /** The first variable sequence number in this class definition. |
mcimadamore@1237 | 963 | */ |
mcimadamore@1237 | 964 | int firstadr; |
mcimadamore@1237 | 965 | |
mcimadamore@1237 | 966 | /** The next available variable sequence number. |
mcimadamore@1237 | 967 | */ |
mcimadamore@1237 | 968 | int nextadr; |
mcimadamore@1237 | 969 | |
mcimadamore@1237 | 970 | /** The list of unreferenced automatic resources. |
mcimadamore@1237 | 971 | */ |
mcimadamore@1237 | 972 | Scope unrefdResources; |
mcimadamore@1237 | 973 | |
mcimadamore@1237 | 974 | /** Set when processing a loop body the second time for DU analysis. */ |
mcimadamore@1237 | 975 | boolean loopPassTwo = false; |
mcimadamore@1237 | 976 | |
mcimadamore@1237 | 977 | class AssignPendingExit extends BaseAnalyzer.PendingExit { |
mcimadamore@1237 | 978 | |
mcimadamore@1237 | 979 | Bits exit_inits; |
mcimadamore@1237 | 980 | Bits exit_uninits; |
mcimadamore@1237 | 981 | |
mcimadamore@1237 | 982 | AssignPendingExit(JCTree tree, Bits inits, Bits uninits) { |
mcimadamore@1237 | 983 | super(tree); |
mcimadamore@1237 | 984 | this.exit_inits = inits.dup(); |
mcimadamore@1237 | 985 | this.exit_uninits = uninits.dup(); |
mcimadamore@1237 | 986 | } |
mcimadamore@1237 | 987 | |
mcimadamore@1237 | 988 | void resolveJump() { |
mcimadamore@1237 | 989 | inits.andSet(exit_inits); |
mcimadamore@1237 | 990 | uninits.andSet(exit_uninits); |
mcimadamore@1237 | 991 | } |
duke@1 | 992 | } |
duke@1 | 993 | |
mcimadamore@1237 | 994 | @Override |
mcimadamore@1237 | 995 | void markDead() { |
mcimadamore@1237 | 996 | inits.inclRange(firstadr, nextadr); |
mcimadamore@1237 | 997 | uninits.inclRange(firstadr, nextadr); |
mcimadamore@1237 | 998 | } |
duke@1 | 999 | |
mcimadamore@1237 | 1000 | /*-------------- Processing variables ----------------------*/ |
duke@1 | 1001 | |
mcimadamore@1237 | 1002 | /** Do we need to track init/uninit state of this symbol? |
mcimadamore@1237 | 1003 | * I.e. is symbol either a local or a blank final variable? |
mcimadamore@1237 | 1004 | */ |
mcimadamore@1237 | 1005 | boolean trackable(VarSymbol sym) { |
mcimadamore@1237 | 1006 | return |
mcimadamore@1237 | 1007 | (sym.owner.kind == MTH || |
mcimadamore@1237 | 1008 | ((sym.flags() & (FINAL | HASINIT | PARAMETER)) == FINAL && |
mcimadamore@1237 | 1009 | classDef.sym.isEnclosedBy((ClassSymbol)sym.owner))); |
duke@1 | 1010 | } |
duke@1 | 1011 | |
mcimadamore@1237 | 1012 | /** Initialize new trackable variable by setting its address field |
mcimadamore@1237 | 1013 | * to the next available sequence number and entering it under that |
mcimadamore@1237 | 1014 | * index into the vars array. |
mcimadamore@1237 | 1015 | */ |
mcimadamore@1237 | 1016 | void newVar(VarSymbol sym) { |
mcimadamore@1237 | 1017 | if (nextadr == vars.length) { |
mcimadamore@1237 | 1018 | VarSymbol[] newvars = new VarSymbol[nextadr * 2]; |
mcimadamore@1237 | 1019 | System.arraycopy(vars, 0, newvars, 0, nextadr); |
mcimadamore@1237 | 1020 | vars = newvars; |
mcimadamore@1237 | 1021 | } |
mcimadamore@1237 | 1022 | sym.adr = nextadr; |
mcimadamore@1237 | 1023 | vars[nextadr] = sym; |
mcimadamore@1237 | 1024 | inits.excl(nextadr); |
mcimadamore@1237 | 1025 | uninits.incl(nextadr); |
mcimadamore@1237 | 1026 | nextadr++; |
mcimadamore@1237 | 1027 | } |
mcimadamore@1237 | 1028 | |
mcimadamore@1237 | 1029 | /** Record an initialization of a trackable variable. |
mcimadamore@1237 | 1030 | */ |
mcimadamore@1237 | 1031 | void letInit(DiagnosticPosition pos, VarSymbol sym) { |
mcimadamore@1237 | 1032 | if (sym.adr >= firstadr && trackable(sym)) { |
mcimadamore@1237 | 1033 | if ((sym.flags() & FINAL) != 0) { |
mcimadamore@1237 | 1034 | if ((sym.flags() & PARAMETER) != 0) { |
mcimadamore@1237 | 1035 | if ((sym.flags() & UNION) != 0) { //multi-catch parameter |
mcimadamore@1237 | 1036 | log.error(pos, "multicatch.parameter.may.not.be.assigned", |
mcimadamore@1237 | 1037 | sym); |
mcimadamore@1237 | 1038 | } |
mcimadamore@1237 | 1039 | else { |
mcimadamore@1237 | 1040 | log.error(pos, "final.parameter.may.not.be.assigned", |
mcimadamore@550 | 1041 | sym); |
mcimadamore@1237 | 1042 | } |
mcimadamore@1237 | 1043 | } else if (!uninits.isMember(sym.adr)) { |
mcimadamore@1237 | 1044 | log.error(pos, |
mcimadamore@1237 | 1045 | loopPassTwo |
mcimadamore@1237 | 1046 | ? "var.might.be.assigned.in.loop" |
mcimadamore@1237 | 1047 | : "var.might.already.be.assigned", |
mcimadamore@1237 | 1048 | sym); |
mcimadamore@1237 | 1049 | } else if (!inits.isMember(sym.adr)) { |
mcimadamore@1237 | 1050 | // reachable assignment |
mcimadamore@1237 | 1051 | uninits.excl(sym.adr); |
mcimadamore@1237 | 1052 | uninitsTry.excl(sym.adr); |
mcimadamore@1237 | 1053 | } else { |
mcimadamore@1237 | 1054 | //log.rawWarning(pos, "unreachable assignment");//DEBUG |
mcimadamore@1237 | 1055 | uninits.excl(sym.adr); |
mcimadamore@550 | 1056 | } |
mcimadamore@1237 | 1057 | } |
mcimadamore@1237 | 1058 | inits.incl(sym.adr); |
mcimadamore@1237 | 1059 | } else if ((sym.flags() & FINAL) != 0) { |
mcimadamore@1237 | 1060 | log.error(pos, "var.might.already.be.assigned", sym); |
mcimadamore@1237 | 1061 | } |
mcimadamore@1237 | 1062 | } |
mcimadamore@1237 | 1063 | |
mcimadamore@1237 | 1064 | /** If tree is either a simple name or of the form this.name or |
mcimadamore@1237 | 1065 | * C.this.name, and tree represents a trackable variable, |
mcimadamore@1237 | 1066 | * record an initialization of the variable. |
mcimadamore@1237 | 1067 | */ |
mcimadamore@1237 | 1068 | void letInit(JCTree tree) { |
mcimadamore@1237 | 1069 | tree = TreeInfo.skipParens(tree); |
mcimadamore@1237 | 1070 | if (tree.hasTag(IDENT) || tree.hasTag(SELECT)) { |
mcimadamore@1237 | 1071 | Symbol sym = TreeInfo.symbol(tree); |
mcimadamore@1237 | 1072 | if (sym.kind == VAR) { |
mcimadamore@1237 | 1073 | letInit(tree.pos(), (VarSymbol)sym); |
duke@1 | 1074 | } |
duke@1 | 1075 | } |
duke@1 | 1076 | } |
duke@1 | 1077 | |
mcimadamore@1237 | 1078 | /** Check that trackable variable is initialized. |
mcimadamore@1237 | 1079 | */ |
mcimadamore@1237 | 1080 | void checkInit(DiagnosticPosition pos, VarSymbol sym) { |
mcimadamore@1237 | 1081 | if ((sym.adr >= firstadr || sym.owner.kind != TYP) && |
mcimadamore@1237 | 1082 | trackable(sym) && |
mcimadamore@1237 | 1083 | !inits.isMember(sym.adr)) { |
mcimadamore@1237 | 1084 | log.error(pos, "var.might.not.have.been.initialized", |
mcimadamore@1237 | 1085 | sym); |
mcimadamore@1237 | 1086 | inits.incl(sym.adr); |
mcimadamore@676 | 1087 | } |
duke@1 | 1088 | } |
duke@1 | 1089 | |
mcimadamore@1237 | 1090 | /** Split (duplicate) inits/uninits into WhenTrue/WhenFalse sets |
mcimadamore@1237 | 1091 | */ |
mcimadamore@1237 | 1092 | void split(boolean setToNull) { |
mcimadamore@1237 | 1093 | initsWhenFalse = inits.dup(); |
mcimadamore@1237 | 1094 | uninitsWhenFalse = uninits.dup(); |
mcimadamore@1237 | 1095 | initsWhenTrue = inits; |
mcimadamore@1237 | 1096 | uninitsWhenTrue = uninits; |
mcimadamore@1237 | 1097 | if (setToNull) |
mcimadamore@1237 | 1098 | inits = uninits = null; |
duke@1 | 1099 | } |
duke@1 | 1100 | |
mcimadamore@1237 | 1101 | /** Merge (intersect) inits/uninits from WhenTrue/WhenFalse sets. |
mcimadamore@1237 | 1102 | */ |
mcimadamore@1237 | 1103 | void merge() { |
mcimadamore@1237 | 1104 | inits = initsWhenFalse.andSet(initsWhenTrue); |
mcimadamore@1237 | 1105 | uninits = uninitsWhenFalse.andSet(uninitsWhenTrue); |
mcimadamore@1237 | 1106 | } |
duke@1 | 1107 | |
mcimadamore@1237 | 1108 | /* ************************************************************************ |
mcimadamore@1237 | 1109 | * Visitor methods for statements and definitions |
mcimadamore@1237 | 1110 | *************************************************************************/ |
duke@1 | 1111 | |
mcimadamore@1237 | 1112 | /** Analyze an expression. Make sure to set (un)inits rather than |
mcimadamore@1237 | 1113 | * (un)initsWhenTrue(WhenFalse) on exit. |
mcimadamore@1237 | 1114 | */ |
mcimadamore@1237 | 1115 | void scanExpr(JCTree tree) { |
mcimadamore@1237 | 1116 | if (tree != null) { |
mcimadamore@1237 | 1117 | scan(tree); |
mcimadamore@1237 | 1118 | if (inits == null) merge(); |
duke@1 | 1119 | } |
duke@1 | 1120 | } |
duke@1 | 1121 | |
mcimadamore@1237 | 1122 | /** Analyze a list of expressions. |
mcimadamore@1237 | 1123 | */ |
mcimadamore@1237 | 1124 | void scanExprs(List<? extends JCExpression> trees) { |
mcimadamore@1237 | 1125 | if (trees != null) |
mcimadamore@1237 | 1126 | for (List<? extends JCExpression> l = trees; l.nonEmpty(); l = l.tail) |
mcimadamore@1237 | 1127 | scanExpr(l.head); |
mcimadamore@1237 | 1128 | } |
mcimadamore@1237 | 1129 | |
mcimadamore@1237 | 1130 | /** Analyze a condition. Make sure to set (un)initsWhenTrue(WhenFalse) |
mcimadamore@1237 | 1131 | * rather than (un)inits on exit. |
mcimadamore@1237 | 1132 | */ |
mcimadamore@1237 | 1133 | void scanCond(JCTree tree) { |
mcimadamore@1237 | 1134 | if (tree.type.isFalse()) { |
mcimadamore@1237 | 1135 | if (inits == null) merge(); |
mcimadamore@1237 | 1136 | initsWhenTrue = inits.dup(); |
mcimadamore@1237 | 1137 | initsWhenTrue.inclRange(firstadr, nextadr); |
mcimadamore@1237 | 1138 | uninitsWhenTrue = uninits.dup(); |
mcimadamore@1237 | 1139 | uninitsWhenTrue.inclRange(firstadr, nextadr); |
mcimadamore@1237 | 1140 | initsWhenFalse = inits; |
mcimadamore@1237 | 1141 | uninitsWhenFalse = uninits; |
mcimadamore@1237 | 1142 | } else if (tree.type.isTrue()) { |
mcimadamore@1237 | 1143 | if (inits == null) merge(); |
mcimadamore@1237 | 1144 | initsWhenFalse = inits.dup(); |
mcimadamore@1237 | 1145 | initsWhenFalse.inclRange(firstadr, nextadr); |
mcimadamore@1237 | 1146 | uninitsWhenFalse = uninits.dup(); |
mcimadamore@1237 | 1147 | uninitsWhenFalse.inclRange(firstadr, nextadr); |
mcimadamore@1237 | 1148 | initsWhenTrue = inits; |
mcimadamore@1237 | 1149 | uninitsWhenTrue = uninits; |
duke@1 | 1150 | } else { |
mcimadamore@1237 | 1151 | scan(tree); |
mcimadamore@1237 | 1152 | if (inits != null) |
mcimadamore@1237 | 1153 | split(tree.type != syms.unknownType); |
duke@1 | 1154 | } |
mcimadamore@1237 | 1155 | if (tree.type != syms.unknownType) |
mcimadamore@1237 | 1156 | inits = uninits = null; |
duke@1 | 1157 | } |
duke@1 | 1158 | |
mcimadamore@1237 | 1159 | /* ------------ Visitor methods for various sorts of trees -------------*/ |
duke@1 | 1160 | |
mcimadamore@1237 | 1161 | public void visitClassDef(JCClassDecl tree) { |
mcimadamore@1237 | 1162 | if (tree.sym == null) return; |
duke@1 | 1163 | |
mcimadamore@1237 | 1164 | JCClassDecl classDefPrev = classDef; |
mcimadamore@1237 | 1165 | int firstadrPrev = firstadr; |
mcimadamore@1237 | 1166 | int nextadrPrev = nextadr; |
mcimadamore@1237 | 1167 | ListBuffer<AssignPendingExit> pendingExitsPrev = pendingExits; |
mcimadamore@1237 | 1168 | Lint lintPrev = lint; |
duke@1 | 1169 | |
mcimadamore@1237 | 1170 | pendingExits = new ListBuffer<AssignPendingExit>(); |
mcimadamore@1237 | 1171 | if (tree.name != names.empty) { |
mcimadamore@1237 | 1172 | firstadr = nextadr; |
mcimadamore@1237 | 1173 | } |
mcimadamore@1237 | 1174 | classDef = tree; |
mcimadamore@1237 | 1175 | lint = lint.augment(tree.sym.attributes_field); |
duke@1 | 1176 | |
mcimadamore@1237 | 1177 | try { |
mcimadamore@1237 | 1178 | // define all the static fields |
duke@1 | 1179 | for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 1180 | if (l.head.hasTag(VARDEF)) { |
mcimadamore@1237 | 1181 | JCVariableDecl def = (JCVariableDecl)l.head; |
mcimadamore@1237 | 1182 | if ((def.mods.flags & STATIC) != 0) { |
mcimadamore@1237 | 1183 | VarSymbol sym = def.sym; |
mcimadamore@1237 | 1184 | if (trackable(sym)) |
mcimadamore@1237 | 1185 | newVar(sym); |
duke@1 | 1186 | } |
duke@1 | 1187 | } |
duke@1 | 1188 | } |
duke@1 | 1189 | |
mcimadamore@1237 | 1190 | // process all the static initializers |
mcimadamore@1237 | 1191 | for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 1192 | if (!l.head.hasTag(METHODDEF) && |
mcimadamore@1237 | 1193 | (TreeInfo.flags(l.head) & STATIC) != 0) { |
mcimadamore@1237 | 1194 | scan(l.head); |
duke@1 | 1195 | } |
duke@1 | 1196 | } |
duke@1 | 1197 | |
mcimadamore@1237 | 1198 | // define all the instance fields |
duke@1 | 1199 | for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 1200 | if (l.head.hasTag(VARDEF)) { |
mcimadamore@1237 | 1201 | JCVariableDecl def = (JCVariableDecl)l.head; |
mcimadamore@1237 | 1202 | if ((def.mods.flags & STATIC) == 0) { |
mcimadamore@1237 | 1203 | VarSymbol sym = def.sym; |
mcimadamore@1237 | 1204 | if (trackable(sym)) |
mcimadamore@1237 | 1205 | newVar(sym); |
mcimadamore@1237 | 1206 | } |
duke@1 | 1207 | } |
duke@1 | 1208 | } |
mcimadamore@1237 | 1209 | |
mcimadamore@1237 | 1210 | // process all the instance initializers |
mcimadamore@1237 | 1211 | for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 1212 | if (!l.head.hasTag(METHODDEF) && |
mcimadamore@1237 | 1213 | (TreeInfo.flags(l.head) & STATIC) == 0) { |
mcimadamore@1237 | 1214 | scan(l.head); |
mcimadamore@1237 | 1215 | } |
mcimadamore@1237 | 1216 | } |
mcimadamore@1237 | 1217 | |
mcimadamore@1237 | 1218 | // process all the methods |
mcimadamore@1237 | 1219 | for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 1220 | if (l.head.hasTag(METHODDEF)) { |
mcimadamore@1237 | 1221 | scan(l.head); |
mcimadamore@1237 | 1222 | } |
mcimadamore@1237 | 1223 | } |
mcimadamore@1237 | 1224 | } finally { |
mcimadamore@1237 | 1225 | pendingExits = pendingExitsPrev; |
mcimadamore@1237 | 1226 | nextadr = nextadrPrev; |
mcimadamore@1237 | 1227 | firstadr = firstadrPrev; |
mcimadamore@1237 | 1228 | classDef = classDefPrev; |
mcimadamore@1237 | 1229 | lint = lintPrev; |
duke@1 | 1230 | } |
mcimadamore@1237 | 1231 | } |
duke@1 | 1232 | |
mcimadamore@1237 | 1233 | public void visitMethodDef(JCMethodDecl tree) { |
mcimadamore@1237 | 1234 | if (tree.body == null) return; |
mcimadamore@1237 | 1235 | |
mcimadamore@1237 | 1236 | Bits initsPrev = inits.dup(); |
mcimadamore@1237 | 1237 | Bits uninitsPrev = uninits.dup(); |
mcimadamore@1237 | 1238 | int nextadrPrev = nextadr; |
mcimadamore@1237 | 1239 | int firstadrPrev = firstadr; |
mcimadamore@1237 | 1240 | Lint lintPrev = lint; |
mcimadamore@1237 | 1241 | |
mcimadamore@1237 | 1242 | lint = lint.augment(tree.sym.attributes_field); |
mcimadamore@1237 | 1243 | |
mcimadamore@1237 | 1244 | Assert.check(pendingExits.isEmpty()); |
mcimadamore@1237 | 1245 | |
mcimadamore@1237 | 1246 | try { |
mcimadamore@1237 | 1247 | boolean isInitialConstructor = |
mcimadamore@1237 | 1248 | TreeInfo.isInitialConstructor(tree); |
mcimadamore@1237 | 1249 | |
mcimadamore@1237 | 1250 | if (!isInitialConstructor) |
mcimadamore@1237 | 1251 | firstadr = nextadr; |
mcimadamore@1237 | 1252 | for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 1253 | JCVariableDecl def = l.head; |
mcimadamore@1237 | 1254 | scan(def); |
mcimadamore@1237 | 1255 | inits.incl(def.sym.adr); |
mcimadamore@1237 | 1256 | uninits.excl(def.sym.adr); |
duke@1 | 1257 | } |
mcimadamore@1237 | 1258 | // else we are in an instance initializer block; |
mcimadamore@1237 | 1259 | // leave caught unchanged. |
mcimadamore@1237 | 1260 | scan(tree.body); |
duke@1 | 1261 | |
mcimadamore@1237 | 1262 | if (isInitialConstructor) { |
mcimadamore@1237 | 1263 | for (int i = firstadr; i < nextadr; i++) |
mcimadamore@1237 | 1264 | if (vars[i].owner == classDef.sym) |
mcimadamore@1237 | 1265 | checkInit(TreeInfo.diagEndPos(tree.body), vars[i]); |
mcimadamore@1237 | 1266 | } |
mcimadamore@1237 | 1267 | List<AssignPendingExit> exits = pendingExits.toList(); |
mcimadamore@1237 | 1268 | pendingExits = new ListBuffer<AssignPendingExit>(); |
mcimadamore@1237 | 1269 | while (exits.nonEmpty()) { |
mcimadamore@1237 | 1270 | AssignPendingExit exit = exits.head; |
mcimadamore@1237 | 1271 | exits = exits.tail; |
mcimadamore@1237 | 1272 | Assert.check(exit.tree.hasTag(RETURN), exit.tree); |
duke@1 | 1273 | if (isInitialConstructor) { |
mcimadamore@1237 | 1274 | inits = exit.exit_inits; |
duke@1 | 1275 | for (int i = firstadr; i < nextadr; i++) |
duke@1 | 1276 | checkInit(exit.tree.pos(), vars[i]); |
duke@1 | 1277 | } |
duke@1 | 1278 | } |
duke@1 | 1279 | } finally { |
mcimadamore@1237 | 1280 | inits = initsPrev; |
mcimadamore@1237 | 1281 | uninits = uninitsPrev; |
mcimadamore@1237 | 1282 | nextadr = nextadrPrev; |
mcimadamore@1237 | 1283 | firstadr = firstadrPrev; |
duke@1 | 1284 | lint = lintPrev; |
duke@1 | 1285 | } |
duke@1 | 1286 | } |
duke@1 | 1287 | |
mcimadamore@1237 | 1288 | public void visitVarDef(JCVariableDecl tree) { |
mcimadamore@1237 | 1289 | boolean track = trackable(tree.sym); |
mcimadamore@1237 | 1290 | if (track && tree.sym.owner.kind == MTH) newVar(tree.sym); |
mcimadamore@1237 | 1291 | if (tree.init != null) { |
mcimadamore@1237 | 1292 | Lint lintPrev = lint; |
mcimadamore@1237 | 1293 | lint = lint.augment(tree.sym.attributes_field); |
mcimadamore@1237 | 1294 | try{ |
mcimadamore@1237 | 1295 | scanExpr(tree.init); |
mcimadamore@1237 | 1296 | if (track) letInit(tree.pos(), tree.sym); |
mcimadamore@1237 | 1297 | } finally { |
mcimadamore@1237 | 1298 | lint = lintPrev; |
mcimadamore@1237 | 1299 | } |
mcimadamore@1237 | 1300 | } |
mcimadamore@1237 | 1301 | } |
duke@1 | 1302 | |
mcimadamore@1237 | 1303 | public void visitBlock(JCBlock tree) { |
mcimadamore@1237 | 1304 | int nextadrPrev = nextadr; |
mcimadamore@1237 | 1305 | scan(tree.stats); |
mcimadamore@1237 | 1306 | nextadr = nextadrPrev; |
mcimadamore@1237 | 1307 | } |
duke@1 | 1308 | |
mcimadamore@1237 | 1309 | public void visitDoLoop(JCDoWhileLoop tree) { |
mcimadamore@1237 | 1310 | ListBuffer<AssignPendingExit> prevPendingExits = pendingExits; |
mcimadamore@1237 | 1311 | boolean prevLoopPassTwo = loopPassTwo; |
mcimadamore@1237 | 1312 | pendingExits = new ListBuffer<AssignPendingExit>(); |
mcimadamore@1237 | 1313 | int prevErrors = log.nerrors; |
mcimadamore@1237 | 1314 | do { |
mcimadamore@1237 | 1315 | Bits uninitsEntry = uninits.dup(); |
mcimadamore@1237 | 1316 | uninitsEntry.excludeFrom(nextadr); |
mcimadamore@1237 | 1317 | scan(tree.body); |
mcimadamore@1237 | 1318 | resolveContinues(tree); |
mcimadamore@1237 | 1319 | scanCond(tree.cond); |
mcimadamore@1237 | 1320 | if (log.nerrors != prevErrors || |
mcimadamore@1237 | 1321 | loopPassTwo || |
mcimadamore@1237 | 1322 | uninitsEntry.dup().diffSet(uninitsWhenTrue).nextBit(firstadr)==-1) |
mcimadamore@1237 | 1323 | break; |
mcimadamore@1237 | 1324 | inits = initsWhenTrue; |
mcimadamore@1237 | 1325 | uninits = uninitsEntry.andSet(uninitsWhenTrue); |
mcimadamore@1237 | 1326 | loopPassTwo = true; |
mcimadamore@1237 | 1327 | } while (true); |
mcimadamore@1237 | 1328 | loopPassTwo = prevLoopPassTwo; |
mcimadamore@1237 | 1329 | inits = initsWhenFalse; |
mcimadamore@1237 | 1330 | uninits = uninitsWhenFalse; |
mcimadamore@1237 | 1331 | resolveBreaks(tree, prevPendingExits); |
mcimadamore@1237 | 1332 | } |
duke@1 | 1333 | |
mcimadamore@1237 | 1334 | public void visitWhileLoop(JCWhileLoop tree) { |
mcimadamore@1237 | 1335 | ListBuffer<AssignPendingExit> prevPendingExits = pendingExits; |
mcimadamore@1237 | 1336 | boolean prevLoopPassTwo = loopPassTwo; |
mcimadamore@1237 | 1337 | Bits initsCond; |
mcimadamore@1237 | 1338 | Bits uninitsCond; |
mcimadamore@1237 | 1339 | pendingExits = new ListBuffer<AssignPendingExit>(); |
mcimadamore@1237 | 1340 | int prevErrors = log.nerrors; |
mcimadamore@1237 | 1341 | do { |
mcimadamore@1237 | 1342 | Bits uninitsEntry = uninits.dup(); |
mcimadamore@1237 | 1343 | uninitsEntry.excludeFrom(nextadr); |
duke@1 | 1344 | scanCond(tree.cond); |
duke@1 | 1345 | initsCond = initsWhenFalse; |
duke@1 | 1346 | uninitsCond = uninitsWhenFalse; |
duke@1 | 1347 | inits = initsWhenTrue; |
duke@1 | 1348 | uninits = uninitsWhenTrue; |
mcimadamore@1237 | 1349 | scan(tree.body); |
mcimadamore@1237 | 1350 | resolveContinues(tree); |
mcimadamore@1237 | 1351 | if (log.nerrors != prevErrors || |
mcimadamore@1237 | 1352 | loopPassTwo || |
mcimadamore@1237 | 1353 | uninitsEntry.dup().diffSet(uninits).nextBit(firstadr) == -1) |
mcimadamore@1237 | 1354 | break; |
mcimadamore@1237 | 1355 | uninits = uninitsEntry.andSet(uninits); |
mcimadamore@1237 | 1356 | loopPassTwo = true; |
mcimadamore@1237 | 1357 | } while (true); |
mcimadamore@1237 | 1358 | loopPassTwo = prevLoopPassTwo; |
mcimadamore@1237 | 1359 | inits = initsCond; |
mcimadamore@1237 | 1360 | uninits = uninitsCond; |
mcimadamore@1237 | 1361 | resolveBreaks(tree, prevPendingExits); |
mcimadamore@1237 | 1362 | } |
mcimadamore@1237 | 1363 | |
mcimadamore@1237 | 1364 | public void visitForLoop(JCForLoop tree) { |
mcimadamore@1237 | 1365 | ListBuffer<AssignPendingExit> prevPendingExits = pendingExits; |
mcimadamore@1237 | 1366 | boolean prevLoopPassTwo = loopPassTwo; |
mcimadamore@1237 | 1367 | int nextadrPrev = nextadr; |
mcimadamore@1237 | 1368 | scan(tree.init); |
mcimadamore@1237 | 1369 | Bits initsCond; |
mcimadamore@1237 | 1370 | Bits uninitsCond; |
mcimadamore@1237 | 1371 | pendingExits = new ListBuffer<AssignPendingExit>(); |
mcimadamore@1237 | 1372 | int prevErrors = log.nerrors; |
mcimadamore@1237 | 1373 | do { |
mcimadamore@1237 | 1374 | Bits uninitsEntry = uninits.dup(); |
mcimadamore@1237 | 1375 | uninitsEntry.excludeFrom(nextadr); |
mcimadamore@1237 | 1376 | if (tree.cond != null) { |
mcimadamore@1237 | 1377 | scanCond(tree.cond); |
mcimadamore@1237 | 1378 | initsCond = initsWhenFalse; |
mcimadamore@1237 | 1379 | uninitsCond = uninitsWhenFalse; |
mcimadamore@1237 | 1380 | inits = initsWhenTrue; |
mcimadamore@1237 | 1381 | uninits = uninitsWhenTrue; |
mcimadamore@1237 | 1382 | } else { |
mcimadamore@1237 | 1383 | initsCond = inits.dup(); |
mcimadamore@1237 | 1384 | initsCond.inclRange(firstadr, nextadr); |
mcimadamore@1237 | 1385 | uninitsCond = uninits.dup(); |
mcimadamore@1237 | 1386 | uninitsCond.inclRange(firstadr, nextadr); |
mcimadamore@1237 | 1387 | } |
mcimadamore@1237 | 1388 | scan(tree.body); |
mcimadamore@1237 | 1389 | resolveContinues(tree); |
mcimadamore@1237 | 1390 | scan(tree.step); |
mcimadamore@1237 | 1391 | if (log.nerrors != prevErrors || |
mcimadamore@1237 | 1392 | loopPassTwo || |
mcimadamore@1237 | 1393 | uninitsEntry.dup().diffSet(uninits).nextBit(firstadr) == -1) |
mcimadamore@1237 | 1394 | break; |
mcimadamore@1237 | 1395 | uninits = uninitsEntry.andSet(uninits); |
mcimadamore@1237 | 1396 | loopPassTwo = true; |
mcimadamore@1237 | 1397 | } while (true); |
mcimadamore@1237 | 1398 | loopPassTwo = prevLoopPassTwo; |
mcimadamore@1237 | 1399 | inits = initsCond; |
mcimadamore@1237 | 1400 | uninits = uninitsCond; |
mcimadamore@1237 | 1401 | resolveBreaks(tree, prevPendingExits); |
mcimadamore@1237 | 1402 | nextadr = nextadrPrev; |
mcimadamore@1237 | 1403 | } |
mcimadamore@1237 | 1404 | |
mcimadamore@1237 | 1405 | public void visitForeachLoop(JCEnhancedForLoop tree) { |
mcimadamore@1237 | 1406 | visitVarDef(tree.var); |
mcimadamore@1237 | 1407 | |
mcimadamore@1237 | 1408 | ListBuffer<AssignPendingExit> prevPendingExits = pendingExits; |
mcimadamore@1237 | 1409 | boolean prevLoopPassTwo = loopPassTwo; |
mcimadamore@1237 | 1410 | int nextadrPrev = nextadr; |
mcimadamore@1237 | 1411 | scan(tree.expr); |
mcimadamore@1237 | 1412 | Bits initsStart = inits.dup(); |
mcimadamore@1237 | 1413 | Bits uninitsStart = uninits.dup(); |
mcimadamore@1237 | 1414 | |
mcimadamore@1237 | 1415 | letInit(tree.pos(), tree.var.sym); |
mcimadamore@1237 | 1416 | pendingExits = new ListBuffer<AssignPendingExit>(); |
mcimadamore@1237 | 1417 | int prevErrors = log.nerrors; |
mcimadamore@1237 | 1418 | do { |
mcimadamore@1237 | 1419 | Bits uninitsEntry = uninits.dup(); |
mcimadamore@1237 | 1420 | uninitsEntry.excludeFrom(nextadr); |
mcimadamore@1237 | 1421 | scan(tree.body); |
mcimadamore@1237 | 1422 | resolveContinues(tree); |
mcimadamore@1237 | 1423 | if (log.nerrors != prevErrors || |
mcimadamore@1237 | 1424 | loopPassTwo || |
mcimadamore@1237 | 1425 | uninitsEntry.dup().diffSet(uninits).nextBit(firstadr) == -1) |
mcimadamore@1237 | 1426 | break; |
mcimadamore@1237 | 1427 | uninits = uninitsEntry.andSet(uninits); |
mcimadamore@1237 | 1428 | loopPassTwo = true; |
mcimadamore@1237 | 1429 | } while (true); |
mcimadamore@1237 | 1430 | loopPassTwo = prevLoopPassTwo; |
mcimadamore@1237 | 1431 | inits = initsStart; |
mcimadamore@1237 | 1432 | uninits = uninitsStart.andSet(uninits); |
mcimadamore@1237 | 1433 | resolveBreaks(tree, prevPendingExits); |
mcimadamore@1237 | 1434 | nextadr = nextadrPrev; |
mcimadamore@1237 | 1435 | } |
mcimadamore@1237 | 1436 | |
mcimadamore@1237 | 1437 | public void visitLabelled(JCLabeledStatement tree) { |
mcimadamore@1237 | 1438 | ListBuffer<AssignPendingExit> prevPendingExits = pendingExits; |
mcimadamore@1237 | 1439 | pendingExits = new ListBuffer<AssignPendingExit>(); |
mcimadamore@1237 | 1440 | scan(tree.body); |
mcimadamore@1237 | 1441 | resolveBreaks(tree, prevPendingExits); |
mcimadamore@1237 | 1442 | } |
mcimadamore@1237 | 1443 | |
mcimadamore@1237 | 1444 | public void visitSwitch(JCSwitch tree) { |
mcimadamore@1237 | 1445 | ListBuffer<AssignPendingExit> prevPendingExits = pendingExits; |
mcimadamore@1237 | 1446 | pendingExits = new ListBuffer<AssignPendingExit>(); |
mcimadamore@1237 | 1447 | int nextadrPrev = nextadr; |
mcimadamore@1237 | 1448 | scanExpr(tree.selector); |
mcimadamore@1237 | 1449 | Bits initsSwitch = inits; |
mcimadamore@1237 | 1450 | Bits uninitsSwitch = uninits.dup(); |
mcimadamore@1237 | 1451 | boolean hasDefault = false; |
mcimadamore@1237 | 1452 | for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 1453 | inits = initsSwitch.dup(); |
mcimadamore@1237 | 1454 | uninits = uninits.andSet(uninitsSwitch); |
mcimadamore@1237 | 1455 | JCCase c = l.head; |
mcimadamore@1237 | 1456 | if (c.pat == null) |
mcimadamore@1237 | 1457 | hasDefault = true; |
mcimadamore@1237 | 1458 | else |
mcimadamore@1237 | 1459 | scanExpr(c.pat); |
mcimadamore@1237 | 1460 | scan(c.stats); |
mcimadamore@1237 | 1461 | addVars(c.stats, initsSwitch, uninitsSwitch); |
mcimadamore@1237 | 1462 | // Warn about fall-through if lint switch fallthrough enabled. |
mcimadamore@1237 | 1463 | } |
mcimadamore@1237 | 1464 | if (!hasDefault) { |
mcimadamore@1237 | 1465 | inits.andSet(initsSwitch); |
mcimadamore@1237 | 1466 | } |
mcimadamore@1237 | 1467 | resolveBreaks(tree, prevPendingExits); |
mcimadamore@1237 | 1468 | nextadr = nextadrPrev; |
mcimadamore@1237 | 1469 | } |
mcimadamore@1237 | 1470 | // where |
mcimadamore@1237 | 1471 | /** Add any variables defined in stats to inits and uninits. */ |
mcimadamore@1237 | 1472 | private void addVars(List<JCStatement> stats, Bits inits, |
mcimadamore@1237 | 1473 | Bits uninits) { |
mcimadamore@1237 | 1474 | for (;stats.nonEmpty(); stats = stats.tail) { |
mcimadamore@1237 | 1475 | JCTree stat = stats.head; |
mcimadamore@1237 | 1476 | if (stat.hasTag(VARDEF)) { |
mcimadamore@1237 | 1477 | int adr = ((JCVariableDecl) stat).sym.adr; |
mcimadamore@1237 | 1478 | inits.excl(adr); |
mcimadamore@1237 | 1479 | uninits.incl(adr); |
mcimadamore@1237 | 1480 | } |
mcimadamore@1237 | 1481 | } |
mcimadamore@1237 | 1482 | } |
mcimadamore@1237 | 1483 | |
mcimadamore@1237 | 1484 | public void visitTry(JCTry tree) { |
mcimadamore@1237 | 1485 | ListBuffer<JCVariableDecl> resourceVarDecls = ListBuffer.lb(); |
mcimadamore@1237 | 1486 | Bits uninitsTryPrev = uninitsTry; |
mcimadamore@1237 | 1487 | ListBuffer<AssignPendingExit> prevPendingExits = pendingExits; |
mcimadamore@1237 | 1488 | pendingExits = new ListBuffer<AssignPendingExit>(); |
mcimadamore@1237 | 1489 | Bits initsTry = inits.dup(); |
mcimadamore@1237 | 1490 | uninitsTry = uninits.dup(); |
mcimadamore@1237 | 1491 | for (JCTree resource : tree.resources) { |
mcimadamore@1237 | 1492 | if (resource instanceof JCVariableDecl) { |
mcimadamore@1237 | 1493 | JCVariableDecl vdecl = (JCVariableDecl) resource; |
mcimadamore@1237 | 1494 | visitVarDef(vdecl); |
mcimadamore@1237 | 1495 | unrefdResources.enter(vdecl.sym); |
mcimadamore@1237 | 1496 | resourceVarDecls.append(vdecl); |
mcimadamore@1237 | 1497 | } else if (resource instanceof JCExpression) { |
mcimadamore@1237 | 1498 | scanExpr((JCExpression) resource); |
mcimadamore@1237 | 1499 | } else { |
mcimadamore@1237 | 1500 | throw new AssertionError(tree); // parser error |
mcimadamore@1237 | 1501 | } |
mcimadamore@1237 | 1502 | } |
mcimadamore@1237 | 1503 | scan(tree.body); |
mcimadamore@1237 | 1504 | uninitsTry.andSet(uninits); |
mcimadamore@1237 | 1505 | Bits initsEnd = inits; |
mcimadamore@1237 | 1506 | Bits uninitsEnd = uninits; |
mcimadamore@1237 | 1507 | int nextadrCatch = nextadr; |
mcimadamore@1237 | 1508 | |
mcimadamore@1237 | 1509 | if (!resourceVarDecls.isEmpty() && |
mcimadamore@1237 | 1510 | lint.isEnabled(Lint.LintCategory.TRY)) { |
mcimadamore@1237 | 1511 | for (JCVariableDecl resVar : resourceVarDecls) { |
mcimadamore@1237 | 1512 | if (unrefdResources.includes(resVar.sym)) { |
mcimadamore@1237 | 1513 | log.warning(Lint.LintCategory.TRY, resVar.pos(), |
mcimadamore@1237 | 1514 | "try.resource.not.referenced", resVar.sym); |
mcimadamore@1237 | 1515 | unrefdResources.remove(resVar.sym); |
mcimadamore@1237 | 1516 | } |
mcimadamore@1237 | 1517 | } |
mcimadamore@1237 | 1518 | } |
mcimadamore@1237 | 1519 | |
mcimadamore@1237 | 1520 | for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) { |
mcimadamore@1237 | 1521 | JCVariableDecl param = l.head.param; |
mcimadamore@1237 | 1522 | inits = initsTry.dup(); |
mcimadamore@1237 | 1523 | uninits = uninitsTry.dup(); |
mcimadamore@1237 | 1524 | scan(param); |
mcimadamore@1237 | 1525 | inits.incl(param.sym.adr); |
mcimadamore@1237 | 1526 | uninits.excl(param.sym.adr); |
mcimadamore@1237 | 1527 | scan(l.head.body); |
mcimadamore@1237 | 1528 | initsEnd.andSet(inits); |
mcimadamore@1237 | 1529 | uninitsEnd.andSet(uninits); |
mcimadamore@1237 | 1530 | nextadr = nextadrCatch; |
mcimadamore@1237 | 1531 | } |
mcimadamore@1237 | 1532 | if (tree.finalizer != null) { |
mcimadamore@1237 | 1533 | inits = initsTry.dup(); |
mcimadamore@1237 | 1534 | uninits = uninitsTry.dup(); |
mcimadamore@1237 | 1535 | ListBuffer<AssignPendingExit> exits = pendingExits; |
mcimadamore@1237 | 1536 | pendingExits = prevPendingExits; |
mcimadamore@1237 | 1537 | scan(tree.finalizer); |
mcimadamore@1237 | 1538 | if (!tree.finallyCanCompleteNormally) { |
mcimadamore@1237 | 1539 | // discard exits and exceptions from try and finally |
mcimadamore@1237 | 1540 | } else { |
mcimadamore@1237 | 1541 | uninits.andSet(uninitsEnd); |
mcimadamore@1237 | 1542 | // FIX: this doesn't preserve source order of exits in catch |
mcimadamore@1237 | 1543 | // versus finally! |
mcimadamore@1237 | 1544 | while (exits.nonEmpty()) { |
mcimadamore@1237 | 1545 | AssignPendingExit exit = exits.next(); |
mcimadamore@1237 | 1546 | if (exit.exit_inits != null) { |
mcimadamore@1237 | 1547 | exit.exit_inits.orSet(inits); |
mcimadamore@1237 | 1548 | exit.exit_uninits.andSet(uninits); |
mcimadamore@1237 | 1549 | } |
mcimadamore@1237 | 1550 | pendingExits.append(exit); |
mcimadamore@1237 | 1551 | } |
mcimadamore@1237 | 1552 | inits.orSet(initsEnd); |
mcimadamore@1237 | 1553 | } |
duke@1 | 1554 | } else { |
mcimadamore@1237 | 1555 | inits = initsEnd; |
mcimadamore@1237 | 1556 | uninits = uninitsEnd; |
mcimadamore@1237 | 1557 | ListBuffer<AssignPendingExit> exits = pendingExits; |
mcimadamore@1237 | 1558 | pendingExits = prevPendingExits; |
mcimadamore@1237 | 1559 | while (exits.nonEmpty()) pendingExits.append(exits.next()); |
duke@1 | 1560 | } |
mcimadamore@1237 | 1561 | uninitsTry.andSet(uninitsTryPrev).andSet(uninits); |
mcimadamore@1237 | 1562 | } |
duke@1 | 1563 | |
mcimadamore@1237 | 1564 | public void visitConditional(JCConditional tree) { |
mcimadamore@1237 | 1565 | scanCond(tree.cond); |
mcimadamore@1237 | 1566 | Bits initsBeforeElse = initsWhenFalse; |
mcimadamore@1237 | 1567 | Bits uninitsBeforeElse = uninitsWhenFalse; |
mcimadamore@1237 | 1568 | inits = initsWhenTrue; |
mcimadamore@1237 | 1569 | uninits = uninitsWhenTrue; |
mcimadamore@1237 | 1570 | if (tree.truepart.type.tag == BOOLEAN && |
mcimadamore@1237 | 1571 | tree.falsepart.type.tag == BOOLEAN) { |
mcimadamore@1237 | 1572 | // if b and c are boolean valued, then |
mcimadamore@1237 | 1573 | // v is (un)assigned after a?b:c when true iff |
mcimadamore@1237 | 1574 | // v is (un)assigned after b when true and |
mcimadamore@1237 | 1575 | // v is (un)assigned after c when true |
mcimadamore@1237 | 1576 | scanCond(tree.truepart); |
mcimadamore@1237 | 1577 | Bits initsAfterThenWhenTrue = initsWhenTrue.dup(); |
mcimadamore@1237 | 1578 | Bits initsAfterThenWhenFalse = initsWhenFalse.dup(); |
mcimadamore@1237 | 1579 | Bits uninitsAfterThenWhenTrue = uninitsWhenTrue.dup(); |
mcimadamore@1237 | 1580 | Bits uninitsAfterThenWhenFalse = uninitsWhenFalse.dup(); |
mcimadamore@1237 | 1581 | inits = initsBeforeElse; |
mcimadamore@1237 | 1582 | uninits = uninitsBeforeElse; |
mcimadamore@1237 | 1583 | scanCond(tree.falsepart); |
mcimadamore@1237 | 1584 | initsWhenTrue.andSet(initsAfterThenWhenTrue); |
mcimadamore@1237 | 1585 | initsWhenFalse.andSet(initsAfterThenWhenFalse); |
mcimadamore@1237 | 1586 | uninitsWhenTrue.andSet(uninitsAfterThenWhenTrue); |
mcimadamore@1237 | 1587 | uninitsWhenFalse.andSet(uninitsAfterThenWhenFalse); |
mcimadamore@1237 | 1588 | } else { |
mcimadamore@1237 | 1589 | scanExpr(tree.truepart); |
mcimadamore@1237 | 1590 | Bits initsAfterThen = inits.dup(); |
mcimadamore@1237 | 1591 | Bits uninitsAfterThen = uninits.dup(); |
mcimadamore@1237 | 1592 | inits = initsBeforeElse; |
mcimadamore@1237 | 1593 | uninits = uninitsBeforeElse; |
mcimadamore@1237 | 1594 | scanExpr(tree.falsepart); |
mcimadamore@1237 | 1595 | inits.andSet(initsAfterThen); |
mcimadamore@1237 | 1596 | uninits.andSet(uninitsAfterThen); |
duke@1 | 1597 | } |
duke@1 | 1598 | } |
duke@1 | 1599 | |
mcimadamore@1237 | 1600 | public void visitIf(JCIf tree) { |
mcimadamore@1237 | 1601 | scanCond(tree.cond); |
mcimadamore@1237 | 1602 | Bits initsBeforeElse = initsWhenFalse; |
mcimadamore@1237 | 1603 | Bits uninitsBeforeElse = uninitsWhenFalse; |
mcimadamore@1237 | 1604 | inits = initsWhenTrue; |
mcimadamore@1237 | 1605 | uninits = uninitsWhenTrue; |
mcimadamore@1237 | 1606 | scan(tree.thenpart); |
mcimadamore@1237 | 1607 | if (tree.elsepart != null) { |
mcimadamore@1237 | 1608 | Bits initsAfterThen = inits.dup(); |
mcimadamore@1237 | 1609 | Bits uninitsAfterThen = uninits.dup(); |
mcimadamore@1237 | 1610 | inits = initsBeforeElse; |
mcimadamore@1237 | 1611 | uninits = uninitsBeforeElse; |
mcimadamore@1237 | 1612 | scan(tree.elsepart); |
mcimadamore@1237 | 1613 | inits.andSet(initsAfterThen); |
mcimadamore@1237 | 1614 | uninits.andSet(uninitsAfterThen); |
darcy@609 | 1615 | } else { |
mcimadamore@1237 | 1616 | inits.andSet(initsBeforeElse); |
mcimadamore@1237 | 1617 | uninits.andSet(uninitsBeforeElse); |
darcy@609 | 1618 | } |
darcy@609 | 1619 | } |
darcy@609 | 1620 | |
mcimadamore@1237 | 1621 | public void visitBreak(JCBreak tree) { |
mcimadamore@1237 | 1622 | recordExit(tree, new AssignPendingExit(tree, inits, uninits)); |
mcimadamore@1237 | 1623 | } |
mcimadamore@1237 | 1624 | |
mcimadamore@1237 | 1625 | public void visitContinue(JCContinue tree) { |
mcimadamore@1237 | 1626 | recordExit(tree, new AssignPendingExit(tree, inits, uninits)); |
mcimadamore@1237 | 1627 | } |
mcimadamore@1237 | 1628 | |
mcimadamore@1237 | 1629 | public void visitReturn(JCReturn tree) { |
mcimadamore@1237 | 1630 | scanExpr(tree.expr); |
mcimadamore@1237 | 1631 | // if not initial constructor, should markDead instead of recordExit |
mcimadamore@1237 | 1632 | recordExit(tree, new AssignPendingExit(tree, inits, uninits)); |
mcimadamore@1237 | 1633 | } |
mcimadamore@1237 | 1634 | |
mcimadamore@1237 | 1635 | public void visitThrow(JCThrow tree) { |
mcimadamore@1237 | 1636 | scanExpr(tree.expr); |
mcimadamore@1237 | 1637 | markDead(); |
mcimadamore@1237 | 1638 | } |
mcimadamore@1237 | 1639 | |
mcimadamore@1237 | 1640 | public void visitApply(JCMethodInvocation tree) { |
mcimadamore@1237 | 1641 | scanExpr(tree.meth); |
mcimadamore@1237 | 1642 | scanExprs(tree.args); |
mcimadamore@1237 | 1643 | } |
mcimadamore@1237 | 1644 | |
mcimadamore@1237 | 1645 | public void visitNewClass(JCNewClass tree) { |
mcimadamore@1237 | 1646 | scanExpr(tree.encl); |
mcimadamore@1237 | 1647 | scanExprs(tree.args); |
mcimadamore@1237 | 1648 | scan(tree.def); |
mcimadamore@1237 | 1649 | } |
mcimadamore@1237 | 1650 | |
mcimadamore@1237 | 1651 | public void visitNewArray(JCNewArray tree) { |
mcimadamore@1237 | 1652 | scanExprs(tree.dims); |
mcimadamore@1237 | 1653 | scanExprs(tree.elems); |
mcimadamore@1237 | 1654 | } |
mcimadamore@1237 | 1655 | |
mcimadamore@1237 | 1656 | public void visitAssert(JCAssert tree) { |
mcimadamore@1237 | 1657 | Bits initsExit = inits.dup(); |
mcimadamore@1237 | 1658 | Bits uninitsExit = uninits.dup(); |
mcimadamore@1237 | 1659 | scanCond(tree.cond); |
mcimadamore@1237 | 1660 | uninitsExit.andSet(uninitsWhenTrue); |
mcimadamore@1237 | 1661 | if (tree.detail != null) { |
mcimadamore@1237 | 1662 | inits = initsWhenFalse; |
mcimadamore@1237 | 1663 | uninits = uninitsWhenFalse; |
mcimadamore@1237 | 1664 | scanExpr(tree.detail); |
duke@1 | 1665 | } |
mcimadamore@1237 | 1666 | inits = initsExit; |
mcimadamore@1237 | 1667 | uninits = uninitsExit; |
duke@1 | 1668 | } |
mcimadamore@1237 | 1669 | |
mcimadamore@1237 | 1670 | public void visitAssign(JCAssign tree) { |
mcimadamore@1237 | 1671 | JCTree lhs = TreeInfo.skipParens(tree.lhs); |
mcimadamore@1237 | 1672 | if (!(lhs instanceof JCIdent)) scanExpr(lhs); |
mcimadamore@1237 | 1673 | scanExpr(tree.rhs); |
mcimadamore@1237 | 1674 | letInit(lhs); |
mcimadamore@1237 | 1675 | } |
mcimadamore@1237 | 1676 | |
mcimadamore@1237 | 1677 | public void visitAssignop(JCAssignOp tree) { |
mcimadamore@1237 | 1678 | scanExpr(tree.lhs); |
mcimadamore@1237 | 1679 | scanExpr(tree.rhs); |
mcimadamore@1237 | 1680 | letInit(tree.lhs); |
mcimadamore@1237 | 1681 | } |
mcimadamore@1237 | 1682 | |
mcimadamore@1237 | 1683 | public void visitUnary(JCUnary tree) { |
mcimadamore@1237 | 1684 | switch (tree.getTag()) { |
mcimadamore@1237 | 1685 | case NOT: |
mcimadamore@1237 | 1686 | scanCond(tree.arg); |
mcimadamore@1237 | 1687 | Bits t = initsWhenFalse; |
mcimadamore@1237 | 1688 | initsWhenFalse = initsWhenTrue; |
mcimadamore@1237 | 1689 | initsWhenTrue = t; |
mcimadamore@1237 | 1690 | t = uninitsWhenFalse; |
mcimadamore@1237 | 1691 | uninitsWhenFalse = uninitsWhenTrue; |
mcimadamore@1237 | 1692 | uninitsWhenTrue = t; |
mcimadamore@1237 | 1693 | break; |
mcimadamore@1237 | 1694 | case PREINC: case POSTINC: |
mcimadamore@1237 | 1695 | case PREDEC: case POSTDEC: |
mcimadamore@1237 | 1696 | scanExpr(tree.arg); |
mcimadamore@1237 | 1697 | letInit(tree.arg); |
mcimadamore@1237 | 1698 | break; |
mcimadamore@1237 | 1699 | default: |
mcimadamore@1237 | 1700 | scanExpr(tree.arg); |
duke@1 | 1701 | } |
duke@1 | 1702 | } |
duke@1 | 1703 | |
mcimadamore@1237 | 1704 | public void visitBinary(JCBinary tree) { |
mcimadamore@1237 | 1705 | switch (tree.getTag()) { |
mcimadamore@1237 | 1706 | case AND: |
mcimadamore@1237 | 1707 | scanCond(tree.lhs); |
mcimadamore@1237 | 1708 | Bits initsWhenFalseLeft = initsWhenFalse; |
mcimadamore@1237 | 1709 | Bits uninitsWhenFalseLeft = uninitsWhenFalse; |
mcimadamore@1237 | 1710 | inits = initsWhenTrue; |
mcimadamore@1237 | 1711 | uninits = uninitsWhenTrue; |
mcimadamore@1237 | 1712 | scanCond(tree.rhs); |
mcimadamore@1237 | 1713 | initsWhenFalse.andSet(initsWhenFalseLeft); |
mcimadamore@1237 | 1714 | uninitsWhenFalse.andSet(uninitsWhenFalseLeft); |
mcimadamore@1237 | 1715 | break; |
mcimadamore@1237 | 1716 | case OR: |
mcimadamore@1237 | 1717 | scanCond(tree.lhs); |
mcimadamore@1237 | 1718 | Bits initsWhenTrueLeft = initsWhenTrue; |
mcimadamore@1237 | 1719 | Bits uninitsWhenTrueLeft = uninitsWhenTrue; |
mcimadamore@1237 | 1720 | inits = initsWhenFalse; |
mcimadamore@1237 | 1721 | uninits = uninitsWhenFalse; |
mcimadamore@1237 | 1722 | scanCond(tree.rhs); |
mcimadamore@1237 | 1723 | initsWhenTrue.andSet(initsWhenTrueLeft); |
mcimadamore@1237 | 1724 | uninitsWhenTrue.andSet(uninitsWhenTrueLeft); |
mcimadamore@1237 | 1725 | break; |
mcimadamore@1237 | 1726 | default: |
mcimadamore@1237 | 1727 | scanExpr(tree.lhs); |
mcimadamore@1237 | 1728 | scanExpr(tree.rhs); |
mcimadamore@1237 | 1729 | } |
mcimadamore@1237 | 1730 | } |
mcimadamore@1237 | 1731 | |
mcimadamore@1237 | 1732 | public void visitIdent(JCIdent tree) { |
mcimadamore@1237 | 1733 | if (tree.sym.kind == VAR) { |
mcimadamore@1237 | 1734 | checkInit(tree.pos(), (VarSymbol)tree.sym); |
mcimadamore@1237 | 1735 | referenced(tree.sym); |
mcimadamore@1237 | 1736 | } |
mcimadamore@1237 | 1737 | } |
mcimadamore@1237 | 1738 | |
mcimadamore@1237 | 1739 | void referenced(Symbol sym) { |
mcimadamore@1237 | 1740 | unrefdResources.remove(sym); |
mcimadamore@1237 | 1741 | } |
mcimadamore@1237 | 1742 | |
mcimadamore@1237 | 1743 | public void visitTopLevel(JCCompilationUnit tree) { |
mcimadamore@1237 | 1744 | // Do nothing for TopLevel since each class is visited individually |
mcimadamore@1237 | 1745 | } |
mcimadamore@1237 | 1746 | |
mcimadamore@1237 | 1747 | /************************************************************************** |
mcimadamore@1237 | 1748 | * main method |
mcimadamore@1237 | 1749 | *************************************************************************/ |
mcimadamore@1237 | 1750 | |
mcimadamore@1237 | 1751 | /** Perform definite assignment/unassignment analysis on a tree. |
mcimadamore@1237 | 1752 | */ |
mcimadamore@1237 | 1753 | public void analyzeTree(Env<AttrContext> env, TreeMaker make) { |
mcimadamore@1237 | 1754 | try { |
mcimadamore@1237 | 1755 | attrEnv = env; |
mcimadamore@1237 | 1756 | JCTree tree = env.tree; |
mcimadamore@1237 | 1757 | Flow.this.make = make; |
mcimadamore@1237 | 1758 | inits = new Bits(); |
mcimadamore@1237 | 1759 | uninits = new Bits(); |
mcimadamore@1237 | 1760 | uninitsTry = new Bits(); |
mcimadamore@1237 | 1761 | initsWhenTrue = initsWhenFalse = |
mcimadamore@1237 | 1762 | uninitsWhenTrue = uninitsWhenFalse = null; |
mcimadamore@1237 | 1763 | if (vars == null) |
mcimadamore@1237 | 1764 | vars = new VarSymbol[32]; |
mcimadamore@1237 | 1765 | else |
mcimadamore@1237 | 1766 | for (int i=0; i<vars.length; i++) |
mcimadamore@1237 | 1767 | vars[i] = null; |
mcimadamore@1237 | 1768 | firstadr = 0; |
mcimadamore@1237 | 1769 | nextadr = 0; |
mcimadamore@1237 | 1770 | pendingExits = new ListBuffer<AssignPendingExit>(); |
mcimadamore@1237 | 1771 | this.classDef = null; |
mcimadamore@1237 | 1772 | unrefdResources = new Scope(env.enclClass.sym); |
mcimadamore@1237 | 1773 | scan(tree); |
mcimadamore@1237 | 1774 | } finally { |
mcimadamore@1237 | 1775 | // note that recursive invocations of this method fail hard |
mcimadamore@1237 | 1776 | inits = uninits = uninitsTry = null; |
mcimadamore@1237 | 1777 | initsWhenTrue = initsWhenFalse = |
mcimadamore@1237 | 1778 | uninitsWhenTrue = uninitsWhenFalse = null; |
mcimadamore@1237 | 1779 | if (vars != null) for (int i=0; i<vars.length; i++) |
mcimadamore@1237 | 1780 | vars[i] = null; |
mcimadamore@1237 | 1781 | firstadr = 0; |
mcimadamore@1237 | 1782 | nextadr = 0; |
mcimadamore@1237 | 1783 | pendingExits = null; |
mcimadamore@1237 | 1784 | Flow.this.make = null; |
mcimadamore@1237 | 1785 | this.classDef = null; |
mcimadamore@1237 | 1786 | unrefdResources = null; |
mcimadamore@935 | 1787 | } |
mcimadamore@935 | 1788 | } |
mcimadamore@935 | 1789 | } |
duke@1 | 1790 | } |