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 & IMPLICIT_CONVERSION_MASK) >> 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 & IMPLICIT_CONVERSION_MASK) >> 4 /* runtime */) {
 101                                         case T_int :
 102                                                 // ~int
 103                                                 this.expression.generateCode(currentScope, codeStream, valueRequired);
 104                                                 if (valueRequired) {
 105                                                         codeStream.iconst_m1();
 106                                                         codeStream.ixor();
 107                                                 }
 108                                                 break;
 109                                         case T_long :
 110                                                 this.expression.generateCode(currentScope, codeStream, valueRequired);
 111                                                 if (valueRequired) {
 112                                                         codeStream.ldc2_w(-1L);
 113                                                         codeStream.lxor();
 114                                                 }
 115                                 }
 116                                 break;
 117                         case MINUS :
 118                                 // - <num>
 119                                 if (this.constant != NotAConstant) {
 120                                         if (valueRequired) {
 121                                                 switch ((this.expression.implicitConversion & IMPLICIT_CONVERSION_MASK) >> 4){ /* runtime */
 122                                                         case T_int :
 123                                                                 codeStream.generateInlinedValue(this.constant.intValue() * -1);
 124                                                                 break;
 125                                                         case T_float :
 126                                                                 codeStream.generateInlinedValue(this.constant.floatValue() * -1.0f);
 127                                                                 break;
 128                                                         case T_long :
 129                                                                 codeStream.generateInlinedValue(this.constant.longValue() * -1L);
 130                                                                 break;
 131                                                         case T_double :
 132                                                                 codeStream.generateInlinedValue(this.constant.doubleValue() * -1.0);
 133                                                 }
 134                                         }
 135                                 } else {
 136                                         this.expression.generateCode(currentScope, codeStream, valueRequired);
 137                                         if (valueRequired) {
 138                                                 switch ((expression.implicitConversion & IMPLICIT_CONVERSION_MASK) >> 4){ /* runtime type */
 139                                                         case T_int :
 140                                                                 codeStream.ineg();
 141                                                                 break;
 142                                                         case T_float :
 143                                                                 codeStream.fneg();
 144                                                                 break;
 145                                                         case T_long :
 146                                                                 codeStream.lneg();
 147                                                                 break;
 148                                                         case T_double :
 149                                                                 codeStream.dneg();
 150                                                 }
 151                                         }
 152                                 }
 153                                 break;
 154                         case PLUS :
 155                                 this.expression.generateCode(currentScope, codeStream, valueRequired);
 156                 }
 157                 if (valueRequired) {
 158                         codeStream.generateImplicitConversion(this.implicitConversion);
 159                 }
 160                 codeStream.recordPositionsFrom(pc, this.sourceStart);
 161         }
 162
 163         /**
 164          * Boolean operator code generation
 165          *      Optimized operations are: &&, ||, <, <=, >, >=, &, |, ^
 166          */
 167         public void generateOptimizedBoolean(
 168                 BlockScope currentScope,
 169                 CodeStream codeStream,
 170                 Label trueLabel,
 171                 Label falseLabel,
 172                 boolean valueRequired) {
 173
 174                 if ((this.constant != Constant.NotAConstant) && (this.constant.typeID() == T_boolean)) {
 175                         super.generateOptimizedBoolean(
 176                                 currentScope,
 177                                 codeStream,
 178                                 trueLabel,
 179                                 falseLabel,
 180                                 valueRequired);
 181                         return;
 182                 }
 183                 if (((this.bits & OperatorMASK) >> OperatorSHIFT) == NOT) {
 184                         this.expression.generateOptimizedBoolean(
 185                                 currentScope,
 186                                 codeStream,
 187                                 falseLabel,
 188                                 trueLabel,
 189                                 valueRequired);
 190                 } else {
 191                         super.generateOptimizedBoolean(
 192                                 currentScope,
 193                                 codeStream,
 194                                 trueLabel,
 195                                 falseLabel,
 196                                 valueRequired);
 197                 }
 198         }
 199
 200         public StringBuffer printExpressionNoParenthesis(int indent, StringBuffer output) {
 201
 202                 output.append(operatorToString()).append(' ');
 203                 return this.expression.printExpression(0, output);
 204         }
 205
 206         public TypeBinding resolveType(BlockScope scope) {
 207
 208                 boolean expressionIsCast;
 209                 if ((expressionIsCast = this.expression instanceof CastExpression) == true) this.expression.bits |= IgnoreNeedForCastCheckMASK; // will check later on
 210                 TypeBinding expressionType = this.expression.resolveType(scope);
 211                 if (expressionType == null) {
 212                         this.constant = NotAConstant;
 213                         return null;
 214                 }
 215                 int expressionTypeID = expressionType.id;
 216                 // autoboxing support
 217                 LookupEnvironment env = scope.environment();
 218                 boolean use15specifics = env.options.sourceLevel >= JDK1_5;
 219                 if (use15specifics) {
 220                         if (!expressionType.isBaseType()) {
 221                                 expressionTypeID = env.computeBoxingType(expressionType).id;
 222                         }
 223                 }
 224                 if (expressionTypeID > 15) {
 225                         this.constant = NotAConstant;
 226                         scope.problemReporter().invalidOperator(this, expressionType);
 227                         return null;
 228                 }
 229
 230                 int tableId;
 231                 switch ((bits & OperatorMASK) >> OperatorSHIFT) {
 232                         case NOT :
 233                                 tableId = AND_AND;
 234                                 break;
 235                         case TWIDDLE :
 236                                 tableId = LEFT_SHIFT;
 237                                 break;
 238                         default :
 239                                 tableId = MINUS;
 240                 } //+ and - cases
 241
 242                 // the code is an int
 243                 // (cast)  left   Op (cast)  rigth --> result
 244                 //  0000   0000       0000   0000      0000
 245                 //  <<16   <<12       <<8    <<4       <<0
 246                 int operatorSignature = OperatorSignatures[tableId][(expressionTypeID << 4) + expressionTypeID];
 247                 this.expression.computeConversion(scope, TypeBinding.wellKnownType(scope, (operatorSignature >>> 16) & 0x0000F), expressionType);
 248                 this.bits |= operatorSignature & 0xF;
 249                 switch (operatorSignature & 0xF) { // only switch on possible result type.....
 250                         case T_boolean :
 251                                 this.resolvedType = BooleanBinding;
 252                                 break;
 253                         case T_byte :
 254                                 this.resolvedType = ByteBinding;
 255                                 break;
 256                         case T_char :
 257                                 this.resolvedType = CharBinding;
 258                                 break;
 259                         case T_double :
 260                                 this.resolvedType = DoubleBinding;
 261                                 break;
 262                         case T_float :
 263                                 this.resolvedType = FloatBinding;
 264                                 break;
 265                         case T_int :
 266                                 this.resolvedType = IntBinding;
 267                                 break;
 268                         case T_long :
 269                                 this.resolvedType = LongBinding;
 270                                 break;
 271                         default : //error........
 272                                 this.constant = Constant.NotAConstant;
 273                                 if (expressionTypeID != T_undefined)
 274                                         scope.problemReporter().invalidOperator(this, expressionType);
 275                                 return null;
 276                 }
 277                 // compute the constant when valid
 278                 if (this.expression.constant != Constant.NotAConstant) {
 279                         this.constant =
 280                                 Constant.computeConstantOperation(
 281                                         this.expression.constant,
 282                                         expressionTypeID,
 283                                         (bits & OperatorMASK) >> OperatorSHIFT);
 284                 } else {
 285                         this.constant = Constant.NotAConstant;
 286                         if (((bits & OperatorMASK) >> OperatorSHIFT) == NOT) {
 287                                 Constant cst = expression.optimizedBooleanConstant();
 288                                 if (cst != Constant.NotAConstant)
 289                                         this.optimizedBooleanConstant = Constant.fromValue(!cst.booleanValue());
 290                         }
 291                 }
 292                 if (expressionIsCast) {
 293                 // check need for operand cast
 294                         CastExpression.checkNeedForArgumentCast(scope, tableId, operatorSignature, this.expression, expressionTypeID);
 295                 }
 296                 return this.resolvedType;
 297         }
 298
 299         public void traverse(
 300                 ASTVisitor visitor,
 301                 BlockScope blockScope) {
 302
 303                 if (visitor.visit(this, blockScope)) {
 304                         this.expression.traverse(visitor, blockScope);
 305                 }
 306                 visitor.endVisit(this, blockScope);
 307         }
 308 }