net.sourceforge.phpeclipse/src/net/sourceforge/phpeclipse/internal/compiler/ast/Continue.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2003 IBM Corporation and others.
   3  * All rights reserved. This program and the accompanying materials
   4  * are made available under the terms of the Common Public License v1.0
   5  * which accompanies this distribution, and is available at
   6  * http://www.eclipse.org/legal/cpl-v10.html
   7  *
   8  * Contributors:
   9  *     IBM Corporation - initial API and implementation
  10  *******************************************************************************/
  11 package net.sourceforge.phpeclipse.internal.compiler.ast;
  12
  13 import net.sourceforge.phpdt.internal.compiler.IAbstractSyntaxTreeVisitor;
  14 import net.sourceforge.phpdt.internal.compiler.flow.FlowContext;
  15 import net.sourceforge.phpdt.internal.compiler.flow.FlowInfo;
  16 import net.sourceforge.phpdt.internal.compiler.lookup.BlockScope;
  17
  18 public class Continue extends BranchStatement {
  19
  20         public Continue(char[] l, int s, int e) {
  21
  22                 super(l, s, e);
  23         }
  24
  25         public FlowInfo analyseCode(
  26                 BlockScope currentScope,
  27                 FlowContext flowContext,
  28                 FlowInfo flowInfo) {
  29
  30                 // here requires to generate a sequence of finally blocks invocations depending corresponding
  31                 // to each of the traversed try statements, so that execution will terminate properly.
  32
  33                 // lookup the label, this should answer the returnContext
  34                 FlowContext targetContext = (label == null)
  35                                 ? flowContext.getTargetContextForDefaultContinue()
  36                                 : flowContext.getTargetContextForContinueLabel(label);
  37
  38                 if (targetContext == null) {
  39                         if (label == null) {
  40                                 currentScope.problemReporter().invalidContinue(this);
  41                         } else {
  42                                 currentScope.problemReporter().undefinedLabel(this);
  43                         }
  44                         return flowInfo; // pretend it did not continue since no actual target
  45                 }
  46
  47                 if (targetContext == FlowContext.NotContinuableContext) {
  48                         currentScope.problemReporter().invalidContinue(this);
  49                         return flowInfo; // pretend it did not continue since no actual target
  50                 }
  51                 targetLabel = targetContext.continueLabel();
  52                 FlowContext traversedContext = flowContext;
  53                 int subIndex = 0, maxSub = 5;
  54                 subroutines = new AstNode[maxSub];
  55
  56                 do {
  57                         AstNode sub;
  58                         if ((sub = traversedContext.subRoutine()) != null) {
  59                                 if (subIndex == maxSub) {
  60                                         System.arraycopy(subroutines, 0, (subroutines = new AstNode[maxSub*=2]), 0, subIndex); // grow
  61                                 }
  62                                 subroutines[subIndex++] = sub;
  63                                 if (sub.cannotReturn()) {
  64                                         break;
  65                                 }
  66                         }
  67                         traversedContext.recordReturnFrom(flowInfo.unconditionalInits());
  68
  69                         AstNode node;
  70                         if ((node = traversedContext.associatedNode) instanceof TryStatement) {
  71                                 TryStatement tryStatement = (TryStatement) node;
  72                                 flowInfo.addInitializationsFrom(tryStatement.subRoutineInits); // collect inits
  73                         } else if (traversedContext == targetContext) {
  74                                 // only record continue info once accumulated through subroutines, and only against target context
  75                                 targetContext.recordContinueFrom(flowInfo);
  76                                 break;
  77                         }
  78                 } while ((traversedContext = traversedContext.parent) != null);
  79
  80                 // resize subroutines
  81                 if (subIndex != maxSub) {
  82                         System.arraycopy(subroutines, 0, (subroutines = new AstNode[subIndex]), 0, subIndex);
  83                 }
  84                 return FlowInfo.DEAD_END;
  85         }
  86
  87         public String toString(int tab) {
  88
  89                 String s = tabString(tab);
  90                 s += "continue "; //$NON-NLS-1$
  91                 if (label != null)
  92                         s += new String(label);
  93                 return s;
  94         }
  95
  96         public void traverse(
  97                 IAbstractSyntaxTreeVisitor visitor,
  98                 BlockScope blockScope) {
  99
 100                 visitor.visit(this, blockScope);
 101                 visitor.endVisit(this, blockScope);
 102         }
 103 }