+/*******************************************************************************
+ * Copyright (c) 2000, 2003 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 net.sourceforge.phpdt.internal.compiler.ast;
-/**
- * A ConditionalExpression is like that : booleanExpression ? trueValue : falseValue;
- * @author Matthieu Casanova
- */
+import net.sourceforge.phpdt.internal.compiler.ASTVisitor;
+import net.sourceforge.phpdt.internal.compiler.flow.FlowContext;
+import net.sourceforge.phpdt.internal.compiler.flow.FlowInfo;
+import net.sourceforge.phpdt.internal.compiler.flow.UnconditionalFlowInfo;
+import net.sourceforge.phpdt.internal.compiler.impl.Constant;
+import net.sourceforge.phpdt.internal.compiler.lookup.BlockScope;
+
public class ConditionalExpression extends OperatorExpression {
- public Expression condition, valueIfTrue, valueIfFalse;
-
- public ConditionalExpression(Expression condition,
- Expression valueIfTrue,
- Expression valueIfFalse) {
- super(-1, condition.sourceStart, valueIfFalse.sourceEnd);
- this.condition = condition;
- this.valueIfTrue = valueIfTrue;
- this.valueIfFalse = valueIfFalse;
- }
-
- public String toStringExpression() {
- final StringBuffer buff = new StringBuffer("(");
- buff.append(condition.toStringExpression());
- buff.append(") ? ");
- buff.append(valueIfTrue.toStringExpression());
- buff.append(" : ");
- buff.append(valueIfFalse.toStringExpression());
- return buff.toString();
- }
+ public Expression condition, valueIfTrue, valueIfFalse;
+
+ public Constant optimizedBooleanConstant;
+
+ public Constant optimizedIfTrueConstant;
+
+ public Constant optimizedIfFalseConstant;
+
+ private int returnTypeSlotSize = 1;
+
+ // for local variables table attributes
+ int trueInitStateIndex = -1;
+
+ int falseInitStateIndex = -1;
+
+ int mergedInitStateIndex = -1;
+
+ public ConditionalExpression(Expression condition, Expression valueIfTrue,
+ Expression valueIfFalse) {
+ this.condition = condition;
+ this.valueIfTrue = valueIfTrue;
+ this.valueIfFalse = valueIfFalse;
+ sourceStart = condition.sourceStart;
+ sourceEnd = valueIfFalse.sourceEnd;
+ }
+
+ public FlowInfo analyseCode(BlockScope currentScope,
+ FlowContext flowContext, FlowInfo flowInfo) {
+
+ Constant cst = this.condition.optimizedBooleanConstant();
+ boolean isConditionOptimizedTrue = cst != NotAConstant
+ && cst.booleanValue() == true;
+ boolean isConditionOptimizedFalse = cst != NotAConstant
+ && cst.booleanValue() == false;
+
+ int mode = flowInfo.reachMode();
+ flowInfo = condition.analyseCode(currentScope, flowContext, flowInfo,
+ cst == NotAConstant);
+
+ // process the if-true part
+ FlowInfo trueFlowInfo = flowInfo.initsWhenTrue().copy();
+ if (isConditionOptimizedFalse) {
+ trueFlowInfo.setReachMode(FlowInfo.UNREACHABLE);
+ }
+ trueInitStateIndex = currentScope.methodScope()
+ .recordInitializationStates(trueFlowInfo);
+ trueFlowInfo = valueIfTrue.analyseCode(currentScope, flowContext,
+ trueFlowInfo);
+
+ // process the if-false part
+ FlowInfo falseFlowInfo = flowInfo.initsWhenFalse().copy();
+ if (isConditionOptimizedTrue) {
+ falseFlowInfo.setReachMode(FlowInfo.UNREACHABLE);
+ }
+ falseInitStateIndex = currentScope.methodScope()
+ .recordInitializationStates(falseFlowInfo);
+ falseFlowInfo = valueIfFalse.analyseCode(currentScope, flowContext,
+ falseFlowInfo);
+
+ // merge if-true & if-false initializations
+ FlowInfo mergedInfo;
+ if (isConditionOptimizedTrue) {
+ mergedInfo = trueFlowInfo
+ .addPotentialInitializationsFrom(falseFlowInfo);
+ } else if (isConditionOptimizedFalse) {
+ mergedInfo = falseFlowInfo
+ .addPotentialInitializationsFrom(trueFlowInfo);
+ } else {
+ // merge using a conditional info - 1GK2BLM
+ // if ((t && (v = t)) ? t : t && (v = f)) r = v; -- ok
+ cst = this.optimizedIfTrueConstant;
+ boolean isValueIfTrueOptimizedTrue = cst != null
+ && cst != NotAConstant && cst.booleanValue() == true;
+ boolean isValueIfTrueOptimizedFalse = cst != null
+ && cst != NotAConstant && cst.booleanValue() == false;
+
+ cst = this.optimizedIfFalseConstant;
+ boolean isValueIfFalseOptimizedTrue = cst != null
+ && cst != NotAConstant && cst.booleanValue() == true;
+ boolean isValueIfFalseOptimizedFalse = cst != null
+ && cst != NotAConstant && cst.booleanValue() == false;
+
+ UnconditionalFlowInfo trueInfoWhenTrue = trueFlowInfo
+ .initsWhenTrue().copy().unconditionalInits();
+ if (isValueIfTrueOptimizedFalse)
+ trueInfoWhenTrue.setReachMode(FlowInfo.UNREACHABLE);
+
+ UnconditionalFlowInfo falseInfoWhenTrue = falseFlowInfo
+ .initsWhenTrue().copy().unconditionalInits();
+ if (isValueIfFalseOptimizedFalse)
+ falseInfoWhenTrue.setReachMode(FlowInfo.UNREACHABLE);
+
+ UnconditionalFlowInfo trueInfoWhenFalse = trueFlowInfo
+ .initsWhenFalse().copy().unconditionalInits();
+ if (isValueIfTrueOptimizedTrue)
+ trueInfoWhenFalse.setReachMode(FlowInfo.UNREACHABLE);
+
+ UnconditionalFlowInfo falseInfoWhenFalse = falseFlowInfo
+ .initsWhenFalse().copy().unconditionalInits();
+ if (isValueIfFalseOptimizedTrue)
+ falseInfoWhenFalse.setReachMode(FlowInfo.UNREACHABLE);
+
+ mergedInfo = FlowInfo.conditional(trueInfoWhenTrue
+ .mergedWith(falseInfoWhenTrue), trueInfoWhenFalse
+ .mergedWith(falseInfoWhenFalse));
+ }
+ mergedInitStateIndex = currentScope.methodScope()
+ .recordInitializationStates(mergedInfo);
+ mergedInfo.setReachMode(mode);
+ return mergedInfo;
+ }
+
+ /**
+ * Code generation for the conditional operator ?:
+ *
+ * @param currentScope
+ * net.sourceforge.phpdt.internal.compiler.lookup.BlockScope
+ * @param codeStream
+ * net.sourceforge.phpdt.internal.compiler.codegen.CodeStream
+ * @param valueRequired
+ * boolean
+ */
+ // public void generateCode(
+ // BlockScope currentScope,
+ // CodeStream codeStream,
+ // boolean valueRequired) {
+ //
+ // int pc = codeStream.position;
+ // Label endifLabel, falseLabel;
+ // if (constant != NotAConstant) {
+ // if (valueRequired)
+ // codeStream.generateConstant(constant, implicitConversion);
+ // codeStream.recordPositionsFrom(pc, this.sourceStart);
+ // return;
+ // }
+ // Constant cst = condition.constant;
+ // Constant condCst = condition.optimizedBooleanConstant();
+ // boolean needTruePart =
+ // !(((cst != NotAConstant) && (cst.booleanValue() == false))
+ // || ((condCst != NotAConstant) && (condCst.booleanValue() == false)));
+ // boolean needFalsePart =
+ // !(((cst != NotAConstant) && (cst.booleanValue() == true))
+ // || ((condCst != NotAConstant) && (condCst.booleanValue() == true)));
+ // endifLabel = new Label(codeStream);
+ //
+ // // Generate code for the condition
+ // boolean needConditionValue = (cst == NotAConstant) && (condCst ==
+ // NotAConstant);
+ // condition.generateOptimizedBoolean(
+ // currentScope,
+ // codeStream,
+ // null,
+ // (falseLabel = new Label(codeStream)),
+ // needConditionValue);
+ //
+ // if (trueInitStateIndex != -1) {
+ // codeStream.removeNotDefinitelyAssignedVariables(
+ // currentScope,
+ // trueInitStateIndex);
+ // codeStream.addDefinitelyAssignedVariables(currentScope,
+ // trueInitStateIndex);
+ // }
+ // // Then code generation
+ // if (needTruePart) {
+ // valueIfTrue.generateCode(currentScope, codeStream, valueRequired);
+ // if (needFalsePart) {
+ // // Jump over the else part
+ // int position = codeStream.position;
+ // codeStream.goto_(endifLabel);
+ // codeStream.updateLastRecordedEndPC(position);
+ // // Tune codestream stack size
+ // if (valueRequired) {
+ // codeStream.decrStackSize(returnTypeSlotSize);
+ // }
+ // }
+ // }
+ // if (needFalsePart) {
+ // falseLabel.place();
+ // if (falseInitStateIndex != -1) {
+ // codeStream.removeNotDefinitelyAssignedVariables(
+ // currentScope,
+ // falseInitStateIndex);
+ // codeStream.addDefinitelyAssignedVariables(currentScope,
+ // falseInitStateIndex);
+ // }
+ // valueIfFalse.generateCode(currentScope, codeStream, valueRequired);
+ // // End of if statement
+ // endifLabel.place();
+ // }
+ // // May loose some local variable initializations : affecting the local
+ // variable attributes
+ // if (mergedInitStateIndex != -1) {
+ // codeStream.removeNotDefinitelyAssignedVariables(
+ // currentScope,
+ // mergedInitStateIndex);
+ // }
+ // // implicit conversion
+ // if (valueRequired)
+ // codeStream.generateImplicitConversion(implicitConversion);
+ // codeStream.recordPositionsFrom(pc, this.sourceStart);
+ // }
+ //
+ // /**
+ // * Optimized boolean code generation for the conditional operator ?:
+ // */
+ // public void generateOptimizedBoolean(
+ // BlockScope currentScope,
+ // CodeStream codeStream,
+ // Label trueLabel,
+ // Label falseLabel,
+ // boolean valueRequired) {
+ //
+ // if ((constant != Constant.NotAConstant) && (constant.typeID() ==
+ // T_boolean) // constant
+ // || (valueIfTrue.implicitConversion >> 4) != T_boolean) { // non boolean
+ // values
+ // super.generateOptimizedBoolean(currentScope, codeStream, trueLabel,
+ // falseLabel, valueRequired);
+ // return;
+ // }
+ // Constant cst = condition.constant;
+ // Constant condCst = condition.optimizedBooleanConstant();
+ // boolean needTruePart =
+ // !(((cst != NotAConstant) && (cst.booleanValue() == false))
+ // || ((condCst != NotAConstant) && (condCst.booleanValue() == false)));
+ // boolean needFalsePart =
+ // !(((cst != NotAConstant) && (cst.booleanValue() == true))
+ // || ((condCst != NotAConstant) && (condCst.booleanValue() == true)));
+ //
+ // Label internalFalseLabel, endifLabel = new Label(codeStream);
+ //
+ // // Generate code for the condition
+ // boolean needConditionValue = (cst == NotAConstant) && (condCst ==
+ // NotAConstant);
+ // condition.generateOptimizedBoolean(
+ // currentScope,
+ // codeStream,
+ // null,
+ // internalFalseLabel = new Label(codeStream),
+ // needConditionValue);
+ //
+ // if (trueInitStateIndex != -1) {
+ // codeStream.removeNotDefinitelyAssignedVariables(
+ // currentScope,
+ // trueInitStateIndex);
+ // codeStream.addDefinitelyAssignedVariables(currentScope,
+ // trueInitStateIndex);
+ // }
+ // // Then code generation
+ // if (needTruePart) {
+ // valueIfTrue.generateOptimizedBoolean(currentScope, codeStream, trueLabel,
+ // falseLabel, valueRequired);
+ //
+ // if (needFalsePart) {
+ // // Jump over the else part
+ // int position = codeStream.position;
+ // codeStream.goto_(endifLabel);
+ // codeStream.updateLastRecordedEndPC(position);
+ // // No need to decrement codestream stack size
+ // // since valueIfTrue was already consumed by branch bytecode
+ // }
+ // }
+ // if (needFalsePart) {
+ // internalFalseLabel.place();
+ // if (falseInitStateIndex != -1) {
+ // codeStream.removeNotDefinitelyAssignedVariables(
+ // currentScope,
+ // falseInitStateIndex);
+ // codeStream.addDefinitelyAssignedVariables(currentScope,
+ // falseInitStateIndex);
+ // }
+ // valueIfFalse.generateOptimizedBoolean(currentScope, codeStream,
+ // trueLabel, falseLabel, valueRequired);
+ //
+ // // End of if statement
+ // endifLabel.place();
+ // }
+ // // May loose some local variable initializations : affecting the local
+ // variable attributes
+ // if (mergedInitStateIndex != -1) {
+ // codeStream.removeNotDefinitelyAssignedVariables(
+ // currentScope,
+ // mergedInitStateIndex);
+ // }
+ // // no implicit conversion for boolean values
+ // codeStream.updateLastRecordedEndPC(codeStream.position);
+ // }
+ //
+ // public Constant optimizedBooleanConstant() {
+ //
+ // return this.optimizedBooleanConstant == null ? this.constant :
+ // this.optimizedBooleanConstant;
+ // }
+ //
+ // public TypeBinding resolveType(BlockScope scope) {
+ // // specs p.368
+ // constant = NotAConstant;
+ // TypeBinding conditionType = condition.resolveTypeExpecting(scope,
+ // BooleanBinding);
+ // TypeBinding valueIfTrueType = valueIfTrue.resolveType(scope);
+ // TypeBinding valueIfFalseType = valueIfFalse.resolveType(scope);
+ // if (conditionType == null || valueIfTrueType == null || valueIfFalseType
+ // == null)
+ // return null;
+ //
+ // // Propagate the constant value from the valueIfTrue and valueIFFalse
+ // expression if it is possible
+ // Constant condConstant, trueConstant, falseConstant;
+ // if ((condConstant = condition.constant) != NotAConstant
+ // && (trueConstant = valueIfTrue.constant) != NotAConstant
+ // && (falseConstant = valueIfFalse.constant) != NotAConstant) {
+ // // all terms are constant expression so we can propagate the constant
+ // // from valueIFTrue or valueIfFalse to teh receiver constant
+ // constant = condConstant.booleanValue() ? trueConstant : falseConstant;
+ // }
+ // if (valueIfTrueType == valueIfFalseType) { // harmed the implicit
+ // conversion
+ // valueIfTrue.implicitWidening(valueIfTrueType, valueIfTrueType);
+ // valueIfFalse.implicitConversion = valueIfTrue.implicitConversion;
+ // if (valueIfTrueType == LongBinding || valueIfTrueType == DoubleBinding) {
+ // returnTypeSlotSize = 2;
+ // }
+ //
+ // if (valueIfTrueType == BooleanBinding) {
+ // this.optimizedIfTrueConstant = valueIfTrue.optimizedBooleanConstant();
+ // this.optimizedIfFalseConstant = valueIfFalse.optimizedBooleanConstant();
+ //
+ // // Propagate the optimized boolean constant if possible
+ // if ((condConstant = condition.optimizedBooleanConstant()) !=
+ // NotAConstant) {
+ //
+ // this.optimizedBooleanConstant = condConstant.booleanValue()
+ // ? optimizedIfTrueConstant
+ // : optimizedIfFalseConstant;
+ // }
+ // }
+ // return this.resolvedType = valueIfTrueType;
+ // }
+ // // Determine the return type depending on argument types
+ // // Numeric types
+ // if (valueIfTrueType.isNumericType() && valueIfFalseType.isNumericType())
+ // {
+ // // (Short x Byte) or (Byte x Short)"
+ // if ((valueIfTrueType == ByteBinding && valueIfFalseType == ShortBinding)
+ // || (valueIfTrueType == ShortBinding && valueIfFalseType == ByteBinding))
+ // {
+ // valueIfTrue.implicitWidening(ShortBinding, valueIfTrueType);
+ // valueIfFalse.implicitWidening(ShortBinding, valueIfFalseType);
+ // this.resolvedType = ShortBinding;
+ // return ShortBinding;
+ // }
+ // // <Byte|Short|Char> x constant(Int) ---> <Byte|Short|Char> and
+ // reciprocally
+ // if ((valueIfTrueType == ByteBinding || valueIfTrueType == ShortBinding ||
+ // valueIfTrueType == CharBinding)
+ // && (valueIfFalseType == IntBinding
+ // && valueIfFalse.isConstantValueOfTypeAssignableToType(valueIfFalseType,
+ // valueIfTrueType))) {
+ // valueIfTrue.implicitWidening(valueIfTrueType, valueIfTrueType);
+ // valueIfFalse.implicitWidening(valueIfTrueType, valueIfFalseType);
+ // this.resolvedType = valueIfTrueType;
+ // return valueIfTrueType;
+ // }
+ // if ((valueIfFalseType == ByteBinding
+ // || valueIfFalseType == ShortBinding
+ // || valueIfFalseType == CharBinding)
+ // && (valueIfTrueType == IntBinding
+ // && valueIfTrue.isConstantValueOfTypeAssignableToType(valueIfTrueType,
+ // valueIfFalseType))) {
+ // valueIfTrue.implicitWidening(valueIfFalseType, valueIfTrueType);
+ // valueIfFalse.implicitWidening(valueIfFalseType, valueIfFalseType);
+ // this.resolvedType = valueIfFalseType;
+ // return valueIfFalseType;
+ // }
+ // // Manual binary numeric promotion
+ // // int
+ // if (BaseTypeBinding.isNarrowing(valueIfTrueType.id, T_int)
+ // && BaseTypeBinding.isNarrowing(valueIfFalseType.id, T_int)) {
+ // valueIfTrue.implicitWidening(IntBinding, valueIfTrueType);
+ // valueIfFalse.implicitWidening(IntBinding, valueIfFalseType);
+ // this.resolvedType = IntBinding;
+ // return IntBinding;
+ // }
+ // // long
+ // if (BaseTypeBinding.isNarrowing(valueIfTrueType.id, T_long)
+ // && BaseTypeBinding.isNarrowing(valueIfFalseType.id, T_long)) {
+ // valueIfTrue.implicitWidening(LongBinding, valueIfTrueType);
+ // valueIfFalse.implicitWidening(LongBinding, valueIfFalseType);
+ // returnTypeSlotSize = 2;
+ // this.resolvedType = LongBinding;
+ // return LongBinding;
+ // }
+ // // float
+ // if (BaseTypeBinding.isNarrowing(valueIfTrueType.id, T_float)
+ // && BaseTypeBinding.isNarrowing(valueIfFalseType.id, T_float)) {
+ // valueIfTrue.implicitWidening(FloatBinding, valueIfTrueType);
+ // valueIfFalse.implicitWidening(FloatBinding, valueIfFalseType);
+ // this.resolvedType = FloatBinding;
+ // return FloatBinding;
+ // }
+ // // double
+ // valueIfTrue.implicitWidening(DoubleBinding, valueIfTrueType);
+ // valueIfFalse.implicitWidening(DoubleBinding, valueIfFalseType);
+ // returnTypeSlotSize = 2;
+ // this.resolvedType = DoubleBinding;
+ // return DoubleBinding;
+ // }
+ // // Type references (null null is already tested)
+ // if ((valueIfTrueType.isBaseType() && valueIfTrueType != NullBinding)
+ // || (valueIfFalseType.isBaseType() && valueIfFalseType != NullBinding)) {
+ // scope.problemReporter().conditionalArgumentsIncompatibleTypes(
+ // this,
+ // valueIfTrueType,
+ // valueIfFalseType);
+ // return null;
+ // }
+ // if (valueIfFalseType.isCompatibleWith(valueIfTrueType)) {
+ // valueIfTrue.implicitWidening(valueIfTrueType, valueIfTrueType);
+ // valueIfFalse.implicitWidening(valueIfTrueType, valueIfFalseType);
+ // this.resolvedType = valueIfTrueType;
+ // return valueIfTrueType;
+ // }
+ // if (valueIfTrueType.isCompatibleWith(valueIfFalseType)) {
+ // valueIfTrue.implicitWidening(valueIfFalseType, valueIfTrueType);
+ // valueIfFalse.implicitWidening(valueIfFalseType, valueIfFalseType);
+ // this.resolvedType = valueIfFalseType;
+ // return valueIfFalseType;
+ // }
+ // scope.problemReporter().conditionalArgumentsIncompatibleTypes(
+ // this,
+ // valueIfTrueType,
+ // valueIfFalseType);
+ // return null;
+ // }
+ public StringBuffer printExpressionNoParenthesis(int indent,
+ StringBuffer output) {
+
+ condition.printExpression(indent, output).append(" ? "); //$NON-NLS-1$
+ valueIfTrue.printExpression(0, output).append(" : "); //$NON-NLS-1$
+ return valueIfFalse.printExpression(0, output);
+ }
+
+ public String toStringExpressionNoParenthesis() {
+ return condition.toStringExpression() + " ? " + //$NON-NLS-1$
+ valueIfTrue.toStringExpression() + " : " + //$NON-NLS-1$
+ valueIfFalse.toStringExpression();
+ }
+
+ public void traverse(ASTVisitor visitor, BlockScope scope) {
+ if (visitor.visit(this, scope)) {
+ condition.traverse(visitor, scope);
+ valueIfTrue.traverse(visitor, scope);
+ valueIfFalse.traverse(visitor, scope);
+ }
+ visitor.endVisit(this, scope);
+ }
}