net.sourceforge.phpeclipse/src/net/sourceforge/phpeclipse/internal/compiler/ast/LocalDeclaration.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.impl.Constant;
  17 import net.sourceforge.phpdt.internal.compiler.lookup.ArrayBinding;
  18 import net.sourceforge.phpdt.internal.compiler.lookup.BaseTypeBinding;
  19 import net.sourceforge.phpdt.internal.compiler.lookup.BlockScope;
  20 import net.sourceforge.phpdt.internal.compiler.lookup.LocalVariableBinding;
  21 import net.sourceforge.phpdt.internal.compiler.lookup.TypeBinding;
  22
  23
  24 public class LocalDeclaration extends AbstractVariableDeclaration {
  25
  26         public LocalVariableBinding binding;
  27
  28         public LocalDeclaration(
  29                 Expression expr,
  30                 char[] name,
  31                 int sourceStart,
  32                 int sourceEnd) {
  33
  34                 initialization = expr;
  35                 this.name = name;
  36                 this.sourceStart = sourceStart;
  37                 this.sourceEnd = sourceEnd;
  38                 if (initialization != null) {
  39                         this.declarationSourceEnd = initialization.sourceEnd;
  40                         this.declarationEnd = initialization.sourceEnd;
  41                 } else {
  42                         this.declarationEnd = sourceEnd;
  43                 }
  44         }
  45
  46         public FlowInfo analyseCode(
  47                 BlockScope currentScope,
  48                 FlowContext flowContext,
  49                 FlowInfo flowInfo) {
  50
  51                 // record variable initialization if any
  52                 if (flowInfo.isReachable()) {
  53                         bits |= IsLocalDeclarationReachableMASK; // only set if actually reached
  54                 }
  55                 if (initialization == null)
  56                         return flowInfo;
  57
  58                 flowInfo =
  59                         initialization
  60                                 .analyseCode(currentScope, flowContext, flowInfo)
  61                                 .unconditionalInits();
  62
  63                 // final int i = (i = 0);
  64                 // no need to complain since (i = 0) part will get the blame
  65                 //if (binding.isFinal() && flowInfo.isPotentiallyAssigned(binding)) {
  66                 //      currentScope.problemReporter().duplicateInitializationOfFinalLocal(binding, this);
  67                 //}
  68
  69                 flowInfo.markAsDefinitelyAssigned(binding);
  70                 return flowInfo;
  71         }
  72
  73         public void checkModifiers() {
  74
  75                 //only potential valid modifier is <<final>>
  76                 if (((modifiers & AccJustFlag) & ~AccFinal) != 0)
  77                         //AccModifierProblem -> other (non-visibility problem)
  78                         //AccAlternateModifierProblem -> duplicate modifier
  79                         //AccModifierProblem | AccAlternateModifierProblem -> visibility problem"
  80
  81                         modifiers = (modifiers & ~AccAlternateModifierProblem) | AccModifierProblem;
  82         }
  83
  84         /**
  85          * Code generation for a local declaration:
  86          *        normal assignment to a local variable + unused variable handling
  87          */
  88 //      public void generateCode(BlockScope currentScope, CodeStream codeStream) {
  89 //
  90 //              // even if not reachable, variable must be added to visible if allocated (28298)
  91 //              if (binding.resolvedPosition != -1) {
  92 //                      codeStream.addVisibleLocalVariable(binding);
  93 //              }
  94 //              if ((bits & IsReachableMASK) == 0) {
  95 //                      return;
  96 //              }
  97 //              int pc = codeStream.position;
  98 //              Constant inlinedValue;
  99 //
 100 //              // something to initialize?
 101 //              if (initialization != null) {
 102 //                      // initialize to constant value?
 103 //                      if ((inlinedValue = initialization.constant) != NotAConstant) {
 104 //                              // forget initializing unused or final locals set to constant value (final ones are inlined)
 105 //                              if (binding.resolvedPosition != -1) { // may need to preserve variable
 106 //                                      int initPC = codeStream.position;
 107 //                                      codeStream.generateConstant(inlinedValue, initialization.implicitConversion);
 108 //                                      codeStream.recordPositionsFrom(initPC, initialization.sourceStart);
 109 //                                      codeStream.store(binding, false);
 110 //                                      binding.recordInitializationStartPC(codeStream.position);
 111 //                                      //                              codeStream.lastInitStateIndexWhenRemovingInits = -2; // reinitialize remove index
 112 //                                      //                              codeStream.lastInitStateIndexWhenAddingInits = -2; // reinitialize add index
 113 //                              }
 114 //                      } else { // initializing to non-constant value
 115 //                              initialization.generateCode(currentScope, codeStream, true);
 116 //                              // if binding unused generate then discard the value
 117 //                              if (binding.resolvedPosition != -1) {
 118 //                                      // 26903, need extra cast to store null in array local var
 119 //                                      if (binding.type.isArrayType()
 120 //                                              && (initialization.resolvedType == NullBinding  // arrayLoc = null
 121 //                                                      || ((initialization instanceof CastExpression)  // arrayLoc = (type[])null
 122 //                                                              && (((CastExpression)initialization).innermostCastedExpression().resolvedType == NullBinding)))){
 123 //                                              codeStream.checkcast(binding.type);
 124 //                                      }
 125 //                                      codeStream.store(binding, false);
 126 //                                      if (binding.initializationCount == 0) {
 127 //                                              /* Variable may have been initialized during the code initializing it
 128 //                                                      e.g. int i = (i = 1);
 129 //                                              */
 130 //                                              binding.recordInitializationStartPC(codeStream.position);
 131 //                                              //                                      codeStream.lastInitStateIndexWhenRemovingInits = -2; // reinitialize remove index
 132 //                                              //                                      codeStream.lastInitStateIndexWhenAddingInits = -2; // reinitialize add index
 133 //                                      }
 134 //                              } else {
 135 //                                      if ((binding.type == LongBinding) || (binding.type == DoubleBinding)) {
 136 //                                              codeStream.pop2();
 137 //                                      } else {
 138 //                                              codeStream.pop();
 139 //                                      }
 140 //                              }
 141 //                      }
 142 //              }
 143 //              codeStream.recordPositionsFrom(pc, this.sourceStart);
 144 //      }
 145
 146         public String name() {
 147
 148                 return String.valueOf(name);
 149         }
 150
 151         public void resolve(BlockScope scope) {
 152
 153                 // create a binding and add it to the scope
 154                 TypeBinding tb = type.resolveType(scope);
 155
 156                 checkModifiers();
 157
 158                 if (tb != null) {
 159                         if (tb == VoidBinding) {
 160                                 scope.problemReporter().variableTypeCannotBeVoid(this);
 161                                 return;
 162                         }
 163                         if (tb.isArrayType() && ((ArrayBinding) tb).leafComponentType == VoidBinding) {
 164                                 scope.problemReporter().variableTypeCannotBeVoidArray(this);
 165                                 return;
 166                         }
 167                 }
 168
 169                 // duplicate checks
 170                 if ((binding = scope.duplicateName(name)) != null) {
 171                         // the name already exists... may carry on with the first binding...
 172                         scope.problemReporter().redefineLocal(this);
 173                 } else {
 174                         if ((modifiers & AccFinal)!= 0 && this.initialization == null) {
 175                                 modifiers |= AccBlankFinal;
 176                         }
 177                         binding = new LocalVariableBinding(this, tb, modifiers, false);
 178                         scope.addLocalVariable(binding);
 179                         binding.constant = NotAConstant;
 180                         // allow to recursivelly target the binding....
 181                         // the correct constant is harmed if correctly computed at the end of this method
 182                 }
 183
 184                 if (tb == null) {
 185                         if (initialization != null)
 186                                 initialization.resolveType(scope); // want to report all possible errors
 187                         return;
 188                 }
 189
 190                 // store the constant for final locals
 191                 if (initialization != null) {
 192                         if (initialization instanceof ArrayInitializer) {
 193                                 TypeBinding initTb = initialization.resolveTypeExpecting(scope, tb);
 194                                 if (initTb != null) {
 195                                         ((ArrayInitializer) initialization).binding = (ArrayBinding) initTb;
 196                                         initialization.implicitWidening(tb, initTb);
 197                                 }
 198                         } else {
 199                                 TypeBinding initTb = initialization.resolveType(scope);
 200                                 if (initTb != null) {
 201                                         if (initialization.isConstantValueOfTypeAssignableToType(initTb, tb)
 202                                                 || (tb.isBaseType() && BaseTypeBinding.isWidening(tb.id, initTb.id))
 203                                                 || initTb.isCompatibleWith(tb))
 204                                                 initialization.implicitWidening(tb, initTb);
 205                                         else
 206                                                 scope.problemReporter().typeMismatchError(initTb, tb, this);
 207                                 }
 208                         }
 209
 210                         // change the constant in the binding when it is final
 211                         // (the optimization of the constant propagation will be done later on)
 212                         // cast from constant actual type to variable type
 213                         binding.constant =
 214                                 binding.isFinal()
 215                                         ? initialization.constant.castTo((tb.id << 4) + initialization.constant.typeID())
 216                                         : NotAConstant;
 217                 }
 218         }
 219
 220         public void traverse(IAbstractSyntaxTreeVisitor visitor, BlockScope scope) {
 221
 222                 if (visitor.visit(this, scope)) {
 223                         type.traverse(visitor, scope);
 224                         if (initialization != null)
 225                                 initialization.traverse(visitor, scope);
 226                 }
 227                 visitor.endVisit(this, scope);
 228         }
 229 }