--- /dev/null
+/*******************************************************************************
+ * Copyright (c) 2000, 2001, 2002 International Business Machines Corp. and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Common Public License v0.5
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/cpl-v05.html
+ *
+ * Contributors:
+ * IBM Corporation - initial API and implementation
+ ******************************************************************************/
+package net.sourceforge.phpdt.internal.compiler.ast;
+
+import net.sourceforge.phpdt.internal.compiler.IAbstractSyntaxTreeVisitor;
+import net.sourceforge.phpdt.internal.compiler.impl.*;
+import net.sourceforge.phpdt.internal.compiler.codegen.*;
+import net.sourceforge.phpdt.internal.compiler.flow.*;
+import net.sourceforge.phpdt.internal.compiler.lookup.*;
+
+public class ConditionalExpression extends OperatorExpression {
+
+ public Expression condition, valueIfTrue, valueIfFalse;
+ private int returnTypeSlotSize = 1;
+
+ // for local variables table attributes
+ int thenInitStateIndex = -1;
+ int elseInitStateIndex = -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 conditionConstant = condition.conditionalConstant();
+
+ flowInfo = condition.analyseCode(currentScope, flowContext, flowInfo, conditionConstant == NotAConstant);
+
+ if (conditionConstant != NotAConstant) {
+ if (conditionConstant.booleanValue() == true) {
+ // TRUE ? left : right
+ FlowInfo resultInfo =
+ valueIfTrue.analyseCode(currentScope, flowContext, flowInfo.initsWhenTrue().unconditionalInits());
+ // analyse valueIfFalse, but do not take into account any of its infos
+ valueIfFalse.analyseCode(
+ currentScope,
+ flowContext,
+ flowInfo.initsWhenFalse().copy().unconditionalInits().markAsFakeReachable(true));
+ mergedInitStateIndex =
+ currentScope.methodScope().recordInitializationStates(resultInfo);
+ return resultInfo;
+ } else {
+ // FALSE ? left : right
+ // analyse valueIfTrue, but do not take into account any of its infos
+ valueIfTrue.analyseCode(
+ currentScope,
+ flowContext,
+ flowInfo.initsWhenTrue().copy().unconditionalInits().markAsFakeReachable(true));
+ FlowInfo mergeInfo =
+ valueIfFalse.analyseCode(currentScope, flowContext, flowInfo.initsWhenFalse().unconditionalInits());
+ mergedInitStateIndex =
+ currentScope.methodScope().recordInitializationStates(mergeInfo);
+ return mergeInfo;
+ }
+ }
+
+ // store a copy of the merged info, so as to compute the local variable attributes afterwards
+ FlowInfo trueInfo = flowInfo.initsWhenTrue();
+ thenInitStateIndex =
+ currentScope.methodScope().recordInitializationStates(trueInfo);
+ FlowInfo falseInfo = flowInfo.initsWhenFalse();
+ elseInitStateIndex =
+ currentScope.methodScope().recordInitializationStates(falseInfo);
+
+ // propagate analysis
+ trueInfo = valueIfTrue.analyseCode(currentScope, flowContext, trueInfo.copy());
+ falseInfo =
+ valueIfFalse.analyseCode(currentScope, flowContext, falseInfo.copy());
+
+ // merge back using a conditional info - 1GK2BLM
+ // if ((t && (v = t)) ? t : t && (v = f)) r = v; -- ok
+ FlowInfo mergedInfo =
+ FlowInfo.conditional(
+ trueInfo.initsWhenTrue().copy().unconditionalInits().mergedWith( // must copy, since could be shared with trueInfo.initsWhenFalse()...
+ falseInfo.initsWhenTrue().copy().unconditionalInits()),
+ trueInfo.initsWhenFalse().unconditionalInits().mergedWith(
+ falseInfo.initsWhenFalse().unconditionalInits()));
+ /*
+ FlowInfo mergedInfo = valueIfTrue.analyseCode(
+ currentScope,
+ flowContext,
+ flowInfo.initsWhenTrue().copy()).
+ unconditionalInits().
+ mergedWith(
+ valueIfFalse.analyseCode(
+ currentScope,
+ flowContext,
+ flowInfo.initsWhenFalse().copy()).
+ unconditionalInits());
+ */
+ mergedInitStateIndex =
+ currentScope.methodScope().recordInitializationStates(mergedInfo);
+ return mergedInfo;
+ }
+
+ /**
+ * Code generation for the conditional operator ?:
+ *
+ * @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) {
+
+ 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.conditionalConstant();
+ 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 (thenInitStateIndex != -1) {
+ codeStream.removeNotDefinitelyAssignedVariables(
+ currentScope,
+ thenInitStateIndex);
+ codeStream.addDefinitelyAssignedVariables(currentScope, thenInitStateIndex);
+ }
+ // 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 (elseInitStateIndex != -1) {
+ codeStream.removeNotDefinitelyAssignedVariables(
+ currentScope,
+ elseInitStateIndex);
+ codeStream.addDefinitelyAssignedVariables(currentScope, elseInitStateIndex);
+ }
+ 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;
+ }
+ int pc = codeStream.position;
+ Constant cst = condition.constant;
+ Constant condCst = condition.conditionalConstant();
+ 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 (thenInitStateIndex != -1) {
+ codeStream.removeNotDefinitelyAssignedVariables(
+ currentScope,
+ thenInitStateIndex);
+ codeStream.addDefinitelyAssignedVariables(currentScope, thenInitStateIndex);
+ }
+ // 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);
+ // Tune codestream stack size
+ //if (valueRequired) {
+ // codeStream.decrStackSize(returnTypeSlotSize);
+ //}
+ }
+ }
+ if (needFalsePart) {
+ internalFalseLabel.place();
+ if (elseInitStateIndex != -1) {
+ codeStream.removeNotDefinitelyAssignedVariables(
+ currentScope,
+ elseInitStateIndex);
+ codeStream.addDefinitelyAssignedVariables(currentScope, elseInitStateIndex);
+ }
+ 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.recordPositionsFrom(pc, this.sourceStart);
+ }
+
+ 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
+ if (condition.constant != NotAConstant
+ && valueIfTrue.constant != NotAConstant
+ && valueIfFalse.constant != NotAConstant) {
+ // all terms are constant expression so we can propagate the constant
+ // from valueIFTrue or valueIfFalse to teh receiver constant
+ constant =
+ (condition.constant.booleanValue())
+ ? valueIfTrue.constant
+ : valueIfFalse.constant;
+ }
+ if (valueIfTrueType == valueIfFalseType) { // harmed the implicit conversion
+ valueIfTrue.implicitWidening(valueIfTrueType, valueIfTrueType);
+ valueIfFalse.implicitConversion = valueIfTrue.implicitConversion;
+ if (valueIfTrueType == LongBinding || valueIfTrueType == DoubleBinding) {
+ returnTypeSlotSize = 2;
+ }
+ this.typeBinding = valueIfTrueType;
+ return 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.typeBinding = 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.typeBinding = 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.typeBinding = 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.typeBinding = 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.typeBinding = 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.typeBinding = FloatBinding;
+ return FloatBinding;
+ }
+ // double
+ valueIfTrue.implicitWidening(DoubleBinding, valueIfTrueType);
+ valueIfFalse.implicitWidening(DoubleBinding, valueIfFalseType);
+ returnTypeSlotSize = 2;
+ this.typeBinding = 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 (scope.areTypesCompatible(valueIfFalseType, valueIfTrueType)) {
+ valueIfTrue.implicitWidening(valueIfTrueType, valueIfTrueType);
+ valueIfFalse.implicitWidening(valueIfTrueType, valueIfFalseType);
+ this.typeBinding = valueIfTrueType;
+ return valueIfTrueType;
+ }
+ if (scope.areTypesCompatible(valueIfTrueType, valueIfFalseType)) {
+ valueIfTrue.implicitWidening(valueIfFalseType, valueIfTrueType);
+ valueIfFalse.implicitWidening(valueIfFalseType, valueIfFalseType);
+ this.typeBinding = valueIfFalseType;
+ return valueIfFalseType;
+ }
+ scope.problemReporter().conditionalArgumentsIncompatibleTypes(
+ this,
+ valueIfTrueType,
+ valueIfFalseType);
+ return null;
+ }
+
+ public String toStringExpressionNoParenthesis() {
+ return condition.toStringExpression() + " ? " + //$NON-NLS-1$
+ valueIfTrue.toStringExpression() + " : " + //$NON-NLS-1$
+ valueIfFalse.toStringExpression();
+ }
+
+ public void traverse(IAbstractSyntaxTreeVisitor visitor, BlockScope scope) {
+ if (visitor.visit(this, scope)) {
+ condition.traverse(visitor, scope);
+ valueIfTrue.traverse(visitor, scope);
+ valueIfFalse.traverse(visitor, scope);
+ }
+ visitor.endVisit(this, scope);
+ }
+}
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