src/org/eclipse/jdt/internal/compiler/ast/UnaryExpression.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2004 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 org.eclipse.jdt.internal.compiler.ast;
  12
  13 import org.eclipse.jdt.internal.compiler.ASTVisitor;
  14 import org.eclipse.jdt.internal.compiler.impl.*;
  15 import org.eclipse.jdt.internal.compiler.codegen.*;
  16 import org.eclipse.jdt.internal.compiler.flow.*;
  17 import org.eclipse.jdt.internal.compiler.lookup.*;
  18
  19 public class UnaryExpression extends OperatorExpression {
  20
  21         public Expression expression;
  22         public Constant optimizedBooleanConstant;
  23
  24         public UnaryExpression(Expression expression, int operator) {
  25                 this.expression = expression;
  26                 this.bits |= operator << OperatorSHIFT; // encode operator
  27         }
  28
  29         public FlowInfo analyseCode(
  30                 BlockScope currentScope,
  31                 FlowContext flowContext,
  32                 FlowInfo flowInfo) {
  33
  34                 if (((bits & OperatorMASK) >> OperatorSHIFT) == NOT) {
  35                         return this.expression
  36                                 .analyseCode(currentScope, flowContext, flowInfo)
  37                                 .asNegatedCondition();
  38                 } else {
  39                         return this.expression.analyseCode(currentScope, flowContext, flowInfo);
  40                 }
  41         }
  42
  43         public Constant optimizedBooleanConstant() {
  44
  45                 return this.optimizedBooleanConstant == null
  46                                 ? this.constant
  47                                 : this.optimizedBooleanConstant;
  48         }
  49
  50         /**
  51          * Code generation for an unary operation
  52          *
  53          * @param currentScope org.eclipse.jdt.internal.compiler.lookup.BlockScope
  54          * @param codeStream org.eclipse.jdt.internal.compiler.codegen.CodeStream
  55          * @param valueRequired boolean
  56          */
  57         public void generateCode(
  58                 BlockScope currentScope,
  59                 CodeStream codeStream,
  60                 boolean valueRequired) {
  61
  62                 int pc = codeStream.position;
  63                 Label falseLabel, endifLabel;
  64                 if (this.constant != Constant.NotAConstant) {
  65                         // inlined value
  66                         if (valueRequired) {
  67                                 codeStream.generateConstant(this.constant, this.implicitConversion);
  68                         }
  69                         codeStream.recordPositionsFrom(pc, this.sourceStart);
  70                         return;
  71                 }
  72                 switch ((bits & OperatorMASK) >> OperatorSHIFT) {
  73                         case NOT :
  74                                 switch (this.expression.implicitConversion >> 4) /* runtime type */ {
  75                                         case T_boolean :
  76                                                 // ! <boolean>
  77                                                 // Generate code for the condition
  78                                                 this.expression.generateOptimizedBoolean(
  79                                                         currentScope,
  80                                                         codeStream,
  81                                                         null,
  82                                                         (falseLabel = new Label(codeStream)),
  83                                                         valueRequired);
  84                                                 if (valueRequired) {
  85                                                         codeStream.iconst_0();
  86                                                         if (falseLabel.hasForwardReferences()) {
  87                                                                 codeStream.goto_(endifLabel = new Label(codeStream));
  88                                                                 codeStream.decrStackSize(1);
  89                                                                 falseLabel.place();
  90                                                                 codeStream.iconst_1();
  91                                                                 endifLabel.place();
  92                                                         }
  93                                                 } else { // 6596: if (!(a && b)){} - must still place falseLabel
  94                                                         falseLabel.place();
  95                                                 }
  96                                                 break;
  97                                 }
  98                                 break;
  99                         case TWIDDLE :
 100                                 switch (this.expression.implicitConversion >> 4 /* runtime */
 101                                         ) {
 102                                         case T_int :
 103                                                 // ~int
 104                                                 this.expression.generateCode(currentScope, codeStream, valueRequired);
 105                                                 if (valueRequired) {
 106                                                         codeStream.iconst_m1();
 107                                                         codeStream.ixor();
 108                                                 }
 109                                                 break;
 110                                         case T_long :
 111                                                 this.expression.generateCode(currentScope, codeStream, valueRequired);
 112                                                 if (valueRequired) {
 113                                                         codeStream.ldc2_w(-1L);
 114                                                         codeStream.lxor();
 115                                                 }
 116                                 }
 117                                 break;
 118                         case MINUS :
 119                                 // - <num>
 120                                 if (this.constant != NotAConstant) {
 121                                         if (valueRequired) {
 122                                                 switch (this.expression.implicitConversion >> 4){ /* runtime */
 123                                                         case T_int :
 124                                                                 codeStream.generateInlinedValue(this.constant.intValue() * -1);
 125                                                                 break;
 126                                                         case T_float :
 127                                                                 codeStream.generateInlinedValue(this.constant.floatValue() * -1.0f);
 128                                                                 break;
 129                                                         case T_long :
 130                                                                 codeStream.generateInlinedValue(this.constant.longValue() * -1L);
 131                                                                 break;
 132                                                         case T_double :
 133                                                                 codeStream.generateInlinedValue(this.constant.doubleValue() * -1.0);
 134                                                 }
 135                                         }
 136                                 } else {
 137                                         this.expression.generateCode(currentScope, codeStream, valueRequired);
 138                                         if (valueRequired) {
 139                                                 switch (expression.implicitConversion >> 4){ /* runtime type */
 140                                                         case T_int :
 141                                                                 codeStream.ineg();
 142                                                                 break;
 143                                                         case T_float :
 144                                                                 codeStream.fneg();
 145                                                                 break;
 146                                                         case T_long :
 147                                                                 codeStream.lneg();
 148                                                                 break;
 149                                                         case T_double :
 150                                                                 codeStream.dneg();
 151                                                 }
 152                                         }
 153                                 }
 154                                 break;
 155                         case PLUS :
 156                                 this.expression.generateCode(currentScope, codeStream, valueRequired);
 157                 }
 158                 if (valueRequired) {
 159                         codeStream.generateImplicitConversion(this.implicitConversion);
 160                 }
 161                 codeStream.recordPositionsFrom(pc, this.sourceStart);
 162         }
 163
 164         /**
 165          * Boolean operator code generation
 166          *      Optimized operations are: &&, ||, <, <=, >, >=, &, |, ^
 167          */
 168         public void generateOptimizedBoolean(
 169                 BlockScope currentScope,
 170                 CodeStream codeStream,
 171                 Label trueLabel,
 172                 Label falseLabel,
 173                 boolean valueRequired) {
 174
 175                 if ((this.constant != Constant.NotAConstant) && (this.constant.typeID() == T_boolean)) {
 176                         super.generateOptimizedBoolean(
 177                                 currentScope,
 178                                 codeStream,
 179                                 trueLabel,
 180                                 falseLabel,
 181                                 valueRequired);
 182                         return;
 183                 }
 184                 if (((this.bits & OperatorMASK) >> OperatorSHIFT) == NOT) {
 185                         this.expression.generateOptimizedBoolean(
 186                                 currentScope,
 187                                 codeStream,
 188                                 falseLabel,
 189                                 trueLabel,
 190                                 valueRequired);
 191                 } else {
 192                         super.generateOptimizedBoolean(
 193                                 currentScope,
 194                                 codeStream,
 195                                 trueLabel,
 196                                 falseLabel,
 197                                 valueRequired);
 198                 }
 199         }
 200
 201         public StringBuffer printExpressionNoParenthesis(int indent, StringBuffer output) {
 202
 203                 output.append(operatorToString()).append(' ');
 204                 return this.expression.printExpression(0, output);
 205         }
 206
 207         public TypeBinding resolveType(BlockScope scope) {
 208
 209                 boolean expressionIsCast;
 210                 if ((expressionIsCast = this.expression instanceof CastExpression) == true) this.expression.bits |= IgnoreNeedForCastCheckMASK; // will check later on
 211                 TypeBinding expressionType = this.expression.resolveType(scope);
 212                 if (expressionType == null) {
 213                         this.constant = NotAConstant;
 214                         return null;
 215                 }
 216                 int expressionTypeId = expressionType.id;
 217                 if (expressionTypeId > 15) {
 218                         this.constant = NotAConstant;
 219                         scope.problemReporter().invalidOperator(this, expressionType);
 220                         return null;
 221                 }
 222
 223                 int tableId;
 224                 switch ((bits & OperatorMASK) >> OperatorSHIFT) {
 225                         case NOT :
 226                                 tableId = AND_AND;
 227                                 break;
 228                         case TWIDDLE :
 229                                 tableId = LEFT_SHIFT;
 230                                 break;
 231                         default :
 232                                 tableId = MINUS;
 233                 } //+ and - cases
 234
 235                 // the code is an int
 236                 // (cast)  left   Op (cast)  rigth --> result
 237                 //  0000   0000       0000   0000      0000
 238                 //  <<16   <<12       <<8    <<4       <<0
 239                 int operatorSignature = OperatorSignatures[tableId][(expressionTypeId << 4) + expressionTypeId];
 240                 this.expression.implicitConversion = operatorSignature >>> 12;
 241                 this.bits |= operatorSignature & 0xF;
 242                 switch (operatorSignature & 0xF) { // only switch on possible result type.....
 243                         case T_boolean :
 244                                 this.resolvedType = BooleanBinding;
 245                                 break;
 246                         case T_byte :
 247                                 this.resolvedType = ByteBinding;
 248                                 break;
 249                         case T_char :
 250                                 this.resolvedType = CharBinding;
 251                                 break;
 252                         case T_double :
 253                                 this.resolvedType = DoubleBinding;
 254                                 break;
 255                         case T_float :
 256                                 this.resolvedType = FloatBinding;
 257                                 break;
 258                         case T_int :
 259                                 this.resolvedType = IntBinding;
 260                                 break;
 261                         case T_long :
 262                                 this.resolvedType = LongBinding;
 263                                 break;
 264                         default : //error........
 265                                 this.constant = Constant.NotAConstant;
 266                                 if (expressionTypeId != T_undefined)
 267                                         scope.problemReporter().invalidOperator(this, expressionType);
 268                                 return null;
 269                 }
 270                 // compute the constant when valid
 271                 if (this.expression.constant != Constant.NotAConstant) {
 272                         this.constant =
 273                                 Constant.computeConstantOperation(
 274                                         this.expression.constant,
 275                                         expressionTypeId,
 276                                         (bits & OperatorMASK) >> OperatorSHIFT);
 277                 } else {
 278                         this.constant = Constant.NotAConstant;
 279                         if (((bits & OperatorMASK) >> OperatorSHIFT) == NOT) {
 280                                 Constant cst = expression.optimizedBooleanConstant();
 281                                 if (cst != Constant.NotAConstant)
 282                                         this.optimizedBooleanConstant = Constant.fromValue(!cst.booleanValue());
 283                         }
 284                 }
 285                 if (expressionIsCast) {
 286                 // check need for operand cast
 287                         CastExpression.checkNeedForArgumentCast(scope, tableId, operatorSignature, this.expression, expressionTypeId);
 288                 }
 289                 return this.resolvedType;
 290         }
 291
 292         public void traverse(
 293                 ASTVisitor visitor,
 294                 BlockScope blockScope) {
 295
 296                 if (visitor.visit(this, blockScope)) {
 297                         this.expression.traverse(visitor, blockScope);
 298                 }
 299                 visitor.endVisit(this, blockScope);
 300         }
 301 }