removed Makefile; lifted repo/org.ibex.tool/src/ to src/
[org.ibex.tool.git] / src / org / eclipse / jdt / internal / compiler / ast / EqualExpression.java
diff --git a/src/org/eclipse/jdt/internal/compiler/ast/EqualExpression.java b/src/org/eclipse/jdt/internal/compiler/ast/EqualExpression.java
new file mode 100644 (file)
index 0000000..0caeb81
--- /dev/null
@@ -0,0 +1,578 @@
+/*******************************************************************************
+ * Copyright (c) 2000, 2004 IBM Corporation and others.
+ * All rights reserved. This program and the accompanying materials 
+ * are made available under the terms of the Common Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/cpl-v10.html
+ * 
+ * Contributors:
+ *     IBM Corporation - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.jdt.internal.compiler.ast;
+
+import org.eclipse.jdt.core.compiler.CharOperation;
+import org.eclipse.jdt.internal.compiler.ASTVisitor;
+import org.eclipse.jdt.internal.compiler.impl.*;
+import org.eclipse.jdt.internal.compiler.codegen.*;
+import org.eclipse.jdt.internal.compiler.flow.*;
+import org.eclipse.jdt.internal.compiler.lookup.*;
+
+public class EqualExpression extends BinaryExpression {
+
+public EqualExpression(Expression left, Expression right,int operator) {
+       super(left,right,operator);
+}
+public FlowInfo analyseCode(BlockScope currentScope, FlowContext flowContext, FlowInfo flowInfo) {
+       if (((bits & OperatorMASK) >> OperatorSHIFT) == EQUAL_EQUAL) {
+               if ((left.constant != NotAConstant) && (left.constant.typeID() == T_boolean)) {
+                       if (left.constant.booleanValue()) { //  true == anything
+                               //  this is equivalent to the right argument inits 
+                               return right.analyseCode(currentScope, flowContext, flowInfo);
+                       } else { // false == anything
+                               //  this is equivalent to the right argument inits negated
+                               return right.analyseCode(currentScope, flowContext, flowInfo).asNegatedCondition();
+                       }
+               }
+               if ((right.constant != NotAConstant) && (right.constant.typeID() == T_boolean)) {
+                       if (right.constant.booleanValue()) { //  anything == true
+                               //  this is equivalent to the right argument inits 
+                               return left.analyseCode(currentScope, flowContext, flowInfo);
+                       } else { // anything == false
+                               //  this is equivalent to the right argument inits negated
+                               return left.analyseCode(currentScope, flowContext, flowInfo).asNegatedCondition();
+                       }
+               }
+               return right.analyseCode(
+                       currentScope, flowContext, 
+                       left.analyseCode(currentScope, flowContext, flowInfo).unconditionalInits()).unconditionalInits();
+       } else { //NOT_EQUAL :
+               if ((left.constant != NotAConstant) && (left.constant.typeID() == T_boolean)) {
+                       if (!left.constant.booleanValue()) { //  false != anything
+                               //  this is equivalent to the right argument inits 
+                               return right.analyseCode(currentScope, flowContext, flowInfo);
+                       } else { // true != anything
+                               //  this is equivalent to the right argument inits negated
+                               return right.analyseCode(currentScope, flowContext, flowInfo).asNegatedCondition();
+                       }
+               }
+               if ((right.constant != NotAConstant) && (right.constant.typeID() == T_boolean)) {
+                       if (!right.constant.booleanValue()) { //  anything != false
+                               //  this is equivalent to the right argument inits 
+                               return left.analyseCode(currentScope, flowContext, flowInfo);
+                       } else { // anything != true
+                               //  this is equivalent to the right argument inits negated
+                               return left.analyseCode(currentScope, flowContext, flowInfo).asNegatedCondition();
+                       }
+               }
+               return right.analyseCode(
+                       currentScope, flowContext, 
+                       left.analyseCode(currentScope, flowContext, flowInfo).unconditionalInits()).asNegatedCondition().unconditionalInits();
+       }
+}
+public final boolean areTypesCastCompatible(BlockScope scope, TypeBinding castType, TypeBinding expressionType) {
+       //see specifications 5.5
+       //A more complete version of this method is provided on
+       //CastExpression (it deals with constant and need runtime checkcast)
+
+       if (castType == expressionType) return true;
+
+       //========ARRAY===============
+       if (expressionType.isArrayType()) {
+               if (castType.isArrayType()) { //------- (castTb.isArray) expressionTb.isArray -----------
+                       TypeBinding expressionEltType = ((ArrayBinding) expressionType).elementsType(scope);
+                       if (expressionEltType.isBaseType())
+                               // <---stop the recursion------- 
+                               return ((ArrayBinding) castType).elementsType(scope) == expressionEltType;
+                       //recursivly on the elts...
+                       return areTypesCastCompatible(scope, ((ArrayBinding) castType).elementsType(scope), expressionEltType);
+               }
+               if (castType.isBaseType()) {
+                       return false;
+               }
+               if (castType.isClass()) { //------(castTb.isClass) expressionTb.isArray --------------- 
+                       if (castType.id == T_Object)
+                               return true;
+                       return false;
+               }
+               if (castType.isInterface()) { //------- (castTb.isInterface) expressionTb.isArray -----------
+                       if (castType.id == T_JavaLangCloneable || castType.id == T_JavaIoSerializable) {
+                               return true;
+                       }
+                       return false;
+               }
+
+               return false;
+       }
+
+       //------------(castType) null--------------
+       if (expressionType == NullBinding) {
+               return !castType.isBaseType();
+       }
+
+       //========BASETYPE==============
+       if (expressionType.isBaseType()) {
+               return false;
+       }
+
+
+       //========REFERENCE TYPE===================
+
+       if (expressionType.isClass()) {
+               if (castType.isArrayType()) { // ---- (castTb.isArray) expressionTb.isClass -------
+                       if (expressionType.id == T_Object)
+                               return true;
+               }
+               if (castType.isBaseType()) {
+                       return false;
+               }
+               if (castType.isClass()) { // ----- (castTb.isClass) expressionTb.isClass ------ 
+                       if (expressionType.isCompatibleWith(castType))
+                               return true;
+                       else {
+                               if (castType.isCompatibleWith(expressionType)) {
+                                       return true;
+                               }
+                               return false;
+                       }
+               }
+               if (castType.isInterface()) { // ----- (castTb.isInterface) expressionTb.isClass -------  
+                       if (expressionType.isCompatibleWith(castType))
+                               return true;                
+                       if (!((ReferenceBinding) expressionType).isFinal()) {
+                               return true;
+                       }
+                       //no subclass for expressionTb, thus compile-time check is valid                        
+               }
+
+               return false;
+       }
+       if (expressionType.isInterface()) {
+               if (castType.isArrayType()) { // ----- (castTb.isArray) expressionTb.isInterface ------
+                       if (expressionType.id == T_JavaLangCloneable || expressionType.id == T_JavaIoSerializable)
+                               //potential runtime error
+                               {
+                               return true;
+                       }
+                       return false;
+               }
+               if (castType.isBaseType()) {
+                       return false;
+               }
+               if (castType.isClass()) { // ----- (castTb.isClass) expressionTb.isInterface --------
+                       if (castType.id == T_Object)
+                               return true;
+                       if (((ReferenceBinding) castType).isFinal()) { //no subclass for castTb, thus compile-time check is valid
+                               if (castType.isCompatibleWith(expressionType)) {
+                                       return true;
+                               }
+                               return false;
+                       }
+                       return true;
+               }
+               if (castType.isInterface()) { // ----- (castTb.isInterface) expressionTb.isInterface -------
+                       if (expressionType.isCompatibleWith(castType))
+                               return true;
+                       if (!castType.isCompatibleWith(expressionType)) {
+                               MethodBinding[] castTbMethods = ((ReferenceBinding) castType).methods();
+                               int castTbMethodsLength = castTbMethods.length;
+                               MethodBinding[] expressionTbMethods = ((ReferenceBinding) expressionType).methods();
+                               int expressionTbMethodsLength = expressionTbMethods.length;
+                               for (int i = 0; i < castTbMethodsLength; i++) {
+                                       for (int j = 0; j < expressionTbMethodsLength; j++) {
+                                               if (CharOperation.equals(castTbMethods[i].selector, expressionTbMethods[j].selector)) {
+                                                       if (castTbMethods[i].returnType != expressionTbMethods[j].returnType) {
+                                                               if (castTbMethods[i].areParametersEqual(expressionTbMethods[j])) {
+                                                                       return false;
+                                                               }
+                                                       }
+                                               }
+                                       }
+                               }
+                       }
+                       return true;
+               }
+               return false;
+       }
+       return false;
+}
+public final void computeConstant(TypeBinding leftType, TypeBinding rightType) {
+       if ((this.left.constant != NotAConstant) && (this.right.constant != NotAConstant)) {
+               this.constant =
+                       Constant.computeConstantOperationEQUAL_EQUAL(
+                               left.constant,
+                               leftType.id,
+                               EQUAL_EQUAL,
+                               right.constant,
+                               rightType.id);
+               if (((this.bits & OperatorMASK) >> OperatorSHIFT) == NOT_EQUAL)
+                       constant = Constant.fromValue(!constant.booleanValue());
+       } else {
+               this.constant = NotAConstant;
+               // no optimization for null == null
+       }
+}
+/**
+ * Normal == or != code generation.
+ *
+ * @param currentScope org.eclipse.jdt.internal.compiler.lookup.BlockScope
+ * @param codeStream org.eclipse.jdt.internal.compiler.codegen.CodeStream
+ * @param valueRequired boolean
+ */
+public void generateCode(BlockScope currentScope, CodeStream codeStream, boolean valueRequired) {
+
+       if (constant != NotAConstant) {
+               int pc = codeStream.position;
+               if (valueRequired) 
+                       codeStream.generateConstant(constant, implicitConversion);
+               codeStream.recordPositionsFrom(pc, this.sourceStart);
+               return;
+       }
+       Label falseLabel;
+       bits |= OnlyValueRequiredMASK;
+       generateOptimizedBoolean(
+               currentScope, 
+               codeStream, 
+               null, 
+               falseLabel = new Label(codeStream), 
+               valueRequired);
+       if (falseLabel.hasForwardReferences()) {
+               if (valueRequired){
+                       // comparison is TRUE 
+                       codeStream.iconst_1();
+                       if ((bits & ValueForReturnMASK) != 0){
+                               codeStream.ireturn();
+                               // comparison is FALSE
+                               falseLabel.place();
+                               codeStream.iconst_0();
+                       } else {
+                               Label endLabel = new Label(codeStream);
+                               codeStream.goto_(endLabel);
+                               codeStream.decrStackSize(1);
+                               // comparison is FALSE
+                               falseLabel.place();
+                               codeStream.iconst_0();
+                               endLabel.place();
+                       }
+               } else {
+                       falseLabel.place();
+               }       
+       }
+}
+/**
+ * Boolean operator code generation
+ *     Optimized operations are: == and !=
+ */
+public void generateOptimizedBoolean(BlockScope currentScope, CodeStream codeStream, Label trueLabel, Label falseLabel, boolean valueRequired) {
+
+       if (constant != Constant.NotAConstant) {
+               super.generateOptimizedBoolean(currentScope, codeStream, trueLabel, falseLabel, valueRequired);
+               return;
+       }
+       if (((bits & OperatorMASK) >> OperatorSHIFT) == EQUAL_EQUAL) {
+               if ((left.implicitConversion & 0xF) /*compile-time*/ == T_boolean) {
+                       generateOptimizedBooleanEqual(currentScope, codeStream, trueLabel, falseLabel, valueRequired);
+               } else {
+                       generateOptimizedNonBooleanEqual(currentScope, codeStream, trueLabel, falseLabel, valueRequired);
+               }
+       } else {
+               if ((left.implicitConversion & 0xF) /*compile-time*/ == T_boolean) {
+                       generateOptimizedBooleanEqual(currentScope, codeStream, falseLabel, trueLabel, valueRequired);
+               } else {
+                       generateOptimizedNonBooleanEqual(currentScope, codeStream, falseLabel, trueLabel, valueRequired);
+               }
+       }
+}
+/**
+ * Boolean generation for == with boolean operands
+ *
+ * Note this code does not optimize conditional constants !!!!
+ */
+public void generateOptimizedBooleanEqual(BlockScope currentScope, CodeStream codeStream, Label trueLabel, Label falseLabel, boolean valueRequired) {
+
+       // optimized cases: true == x, false == x
+       if (left.constant != NotAConstant) {
+               boolean inline = left.constant.booleanValue();
+               right.generateOptimizedBoolean(currentScope, codeStream, (inline ? trueLabel : falseLabel), (inline ? falseLabel : trueLabel), valueRequired);
+               return;
+       } // optimized cases: x == true, x == false
+       if (right.constant != NotAConstant) {
+               boolean inline = right.constant.booleanValue();
+               left.generateOptimizedBoolean(currentScope, codeStream, (inline ? trueLabel : falseLabel), (inline ? falseLabel : trueLabel), valueRequired);
+               return;
+       }
+       // default case
+       left.generateCode(currentScope, codeStream, valueRequired);
+       right.generateCode(currentScope, codeStream, valueRequired);
+       if (valueRequired) {
+               if (falseLabel == null) {
+                       if (trueLabel != null) {
+                               // implicit falling through the FALSE case
+                               codeStream.if_icmpeq(trueLabel);
+                       }
+               } else {
+                       // implicit falling through the TRUE case
+                       if (trueLabel == null) {
+                               codeStream.if_icmpne(falseLabel);
+                       } else {
+                               // no implicit fall through TRUE/FALSE --> should never occur
+                       }
+               }
+       }
+       // reposition the endPC
+       codeStream.updateLastRecordedEndPC(codeStream.position);                                        
+}
+/**
+ * Boolean generation for == with non-boolean operands
+ *
+ */
+public void generateOptimizedNonBooleanEqual(BlockScope currentScope, CodeStream codeStream, Label trueLabel, Label falseLabel, boolean valueRequired) {
+
+       int pc = codeStream.position;
+       Constant inline;
+       if ((inline = right.constant) != NotAConstant) {
+               // optimized case: x == 0
+               if (((left.implicitConversion >> 4) == T_int) && (inline.intValue() == 0)) {
+                       left.generateCode(currentScope, codeStream, valueRequired);
+                       if (valueRequired) {
+                               if (falseLabel == null) {
+                                       if (trueLabel != null) {
+                                               // implicit falling through the FALSE case
+                                               codeStream.ifeq(trueLabel);
+                                       }
+                               } else {
+                                       // implicit falling through the TRUE case
+                                       if (trueLabel == null) {
+                                               codeStream.ifne(falseLabel);
+                                       } else {
+                                               // no implicit fall through TRUE/FALSE --> should never occur
+                                       }
+                               }
+                       }
+                       codeStream.recordPositionsFrom(pc, this.sourceStart);
+                       return;
+               }
+       }
+       if ((inline = left.constant) != NotAConstant) {
+               // optimized case: 0 == x
+               if (((left.implicitConversion >> 4) == T_int)
+                       && (inline.intValue() == 0)) {
+                       right.generateCode(currentScope, codeStream, valueRequired);
+                       if (valueRequired) {
+                               if (falseLabel == null) {
+                                       if (trueLabel != null) {
+                                               // implicit falling through the FALSE case
+                                               codeStream.ifeq(trueLabel);
+                                       }
+                               } else {
+                                       // implicit falling through the TRUE case
+                                       if (trueLabel == null) {
+                                               codeStream.ifne(falseLabel);
+                                       } else {
+                                               // no implicit fall through TRUE/FALSE --> should never occur
+                                       }
+                               }
+                       }
+                       codeStream.recordPositionsFrom(pc, this.sourceStart);
+                       return;
+               }
+       }
+       // null cases
+       // optimized case: x == null
+       if (right instanceof NullLiteral) {
+               if (left instanceof NullLiteral) {
+                       // null == null
+                       if (valueRequired) {
+                                       if ((bits & OnlyValueRequiredMASK) != 0) {
+                                               if (((bits & OperatorMASK) >> OperatorSHIFT) == EQUAL_EQUAL) {
+                                                       codeStream.iconst_1();
+                                               } else {
+                                                       codeStream.iconst_0();
+                                               }
+                                       } else {
+                                               if (falseLabel == null) {
+                                                       // implicit falling through the FALSE case
+                                                       if (trueLabel != null) {
+                                                               codeStream.goto_(trueLabel);
+                                                       }
+                                               }
+                               }
+                       }
+               } else {
+                       left.generateCode(currentScope, codeStream, valueRequired);
+                       if (valueRequired) {
+                               if (falseLabel == null) {
+                                       if (trueLabel != null) {
+                                               // implicit falling through the FALSE case
+                                               codeStream.ifnull(trueLabel);
+                                       }
+                               } else {
+                                       // implicit falling through the TRUE case
+                                       if (trueLabel == null) {
+                                               codeStream.ifnonnull(falseLabel);
+                                       } else {
+                                               // no implicit fall through TRUE/FALSE --> should never occur
+                                       }
+                               }
+                       }
+               }
+               codeStream.recordPositionsFrom(pc, this.sourceStart);
+               return;
+       } else if (left instanceof NullLiteral) { // optimized case: null == x
+               right.generateCode(currentScope, codeStream, valueRequired);
+               if (valueRequired) {
+                       if (falseLabel == null) {
+                               if (trueLabel != null) {
+                                       // implicit falling through the FALSE case
+                                       codeStream.ifnull(trueLabel);
+                               }
+                       } else {
+                               // implicit falling through the TRUE case
+                               if (trueLabel == null) {
+                                       codeStream.ifnonnull(falseLabel);
+                               } else {
+                                       // no implicit fall through TRUE/FALSE --> should never occur
+                               }
+                       }
+               }
+               codeStream.recordPositionsFrom(pc, this.sourceStart);
+               return;
+       }
+
+       // default case
+       left.generateCode(currentScope, codeStream, valueRequired);
+       right.generateCode(currentScope, codeStream, valueRequired);
+       if (valueRequired) {
+               if (falseLabel == null) {
+                       if (trueLabel != null) {
+                               // implicit falling through the FALSE case
+                               switch (left.implicitConversion >> 4) { // operand runtime type
+                                       case T_int :
+                                               codeStream.if_icmpeq(trueLabel);
+                                               break;
+                                       case T_float :
+                                               codeStream.fcmpl();
+                                               codeStream.ifeq(trueLabel);
+                                               break;
+                                       case T_long :
+                                               codeStream.lcmp();
+                                               codeStream.ifeq(trueLabel);
+                                               break;
+                                       case T_double :
+                                               codeStream.dcmpl();
+                                               codeStream.ifeq(trueLabel);
+                                               break;
+                                       default :
+                                               codeStream.if_acmpeq(trueLabel);
+                               }
+                       }
+               } else {
+                       // implicit falling through the TRUE case
+                       if (trueLabel == null) {
+                               switch (left.implicitConversion >> 4) { // operand runtime type
+                                       case T_int :
+                                               codeStream.if_icmpne(falseLabel);
+                                               break;
+                                       case T_float :
+                                               codeStream.fcmpl();
+                                               codeStream.ifne(falseLabel);
+                                               break;
+                                       case T_long :
+                                               codeStream.lcmp();
+                                               codeStream.ifne(falseLabel);
+                                               break;
+                                       case T_double :
+                                               codeStream.dcmpl();
+                                               codeStream.ifne(falseLabel);
+                                               break;
+                                       default :
+                                               codeStream.if_acmpne(falseLabel);
+                               }
+                       } else {
+                               // no implicit fall through TRUE/FALSE --> should never occur
+                       }
+               }
+       }
+       codeStream.recordPositionsFrom(pc, this.sourceStart);
+}
+public boolean isCompactableOperation() {
+       return false;
+}
+public TypeBinding resolveType(BlockScope scope) {
+
+               boolean leftIsCast, rightIsCast;
+               if ((leftIsCast = left instanceof CastExpression) == true) left.bits |= IgnoreNeedForCastCheckMASK; // will check later on
+               TypeBinding leftType = left.resolveType(scope);
+
+               if ((rightIsCast = right instanceof CastExpression) == true) right.bits |= IgnoreNeedForCastCheckMASK; // will check later on
+               TypeBinding rightType = right.resolveType(scope);
+
+       // always return BooleanBinding
+       if (leftType == null || rightType == null){
+               constant = NotAConstant;                
+               return null;
+       }
+
+       // both base type
+       if (leftType.isBaseType() && rightType.isBaseType()) {
+               // the code is an int
+               // (cast)  left   == (cast)  right --> result
+               //  0000   0000       0000   0000      0000
+               //  <<16   <<12       <<8    <<4       <<0
+               int operatorSignature = OperatorSignatures[EQUAL_EQUAL][ (leftType.id << 4) + rightType.id];
+               left.implicitConversion = operatorSignature >>> 12;
+               right.implicitConversion = (operatorSignature >>> 4) & 0x000FF;
+               bits |= operatorSignature & 0xF;                
+               if ((operatorSignature & 0x0000F) == T_undefined) {
+                       constant = Constant.NotAConstant;
+                       scope.problemReporter().invalidOperator(this, leftType, rightType);
+                       return null;
+               }
+               // check need for operand cast
+               if (leftIsCast || rightIsCast) {
+                       CastExpression.checkNeedForArgumentCasts(scope, EQUAL_EQUAL, operatorSignature, left, leftType.id, leftIsCast, right, rightType.id, rightIsCast);
+               }
+               computeConstant(leftType, rightType);
+               return this.resolvedType = BooleanBinding;
+       }
+
+       // Object references 
+       // spec 15.20.3
+       if (areTypesCastCompatible(scope, rightType, leftType) || areTypesCastCompatible(scope, leftType, rightType)) {
+               // (special case for String)
+               if ((rightType.id == T_String) && (leftType.id == T_String)) {
+                       computeConstant(leftType, rightType);
+               } else {
+                       constant = NotAConstant;
+               }
+               if (rightType.id == T_String) {
+                       right.implicitConversion = String2String;
+               }
+               if (leftType.id == T_String) {
+                       left.implicitConversion = String2String;
+               }
+               // check need for operand cast
+               boolean unnecessaryLeftCast = (left.bits & UnnecessaryCastMask) != 0;
+               boolean unnecessaryRightCast = (right.bits & UnnecessaryCastMask) != 0;
+               if (unnecessaryLeftCast || unnecessaryRightCast) {
+                       TypeBinding alternateLeftType = unnecessaryLeftCast ? ((CastExpression)left).expression.resolvedType : leftType;
+                       TypeBinding alternateRightType = unnecessaryRightCast ? ((CastExpression)right).expression.resolvedType : rightType;
+                       if (areTypesCastCompatible(scope, alternateLeftType, alternateRightType)
+                                       || areTypesCastCompatible(scope, alternateRightType, alternateLeftType)) {
+                               if (unnecessaryLeftCast) scope.problemReporter().unnecessaryCast((CastExpression)left); 
+                               if (unnecessaryRightCast) scope.problemReporter().unnecessaryCast((CastExpression)right);
+                       }
+               }
+               return this.resolvedType = BooleanBinding;
+       }
+       constant = NotAConstant;
+       scope.problemReporter().notCompatibleTypesError(this, leftType, rightType);
+       return null;
+}
+public void traverse(ASTVisitor visitor, BlockScope scope) {
+       if (visitor.visit(this, scope)) {
+               left.traverse(visitor, scope);
+               right.traverse(visitor, scope);
+       }
+       visitor.endVisit(this, scope);
+}
+}