-/*******************************************************************************
- * 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.codegen.CodeStream;
-import net.sourceforge.phpdt.internal.compiler.codegen.Label;
-import net.sourceforge.phpdt.internal.compiler.flow.FlowContext;
-import net.sourceforge.phpdt.internal.compiler.flow.FlowInfo;
-import net.sourceforge.phpdt.internal.compiler.impl.Constant;
-import net.sourceforge.phpdt.internal.compiler.lookup.BlockScope;
-import net.sourceforge.phpdt.internal.compiler.lookup.TypeBinding;
-
+import java.util.List;
+import java.util.ArrayList;
+
+/**
+ * This is a if statement.
+ * if (condition)
+ * statement
+ * (elseif statement)*
+ * else statement
+ * @author Matthieu Casanova
+ */
public class IfStatement extends Statement {
-
- //this class represents the case of only one statement in
- //either else and/or then branches.
-
- public Expression condition;
- public Statement thenStatement;
- public Statement elseStatement;
-
- boolean thenExit;
-
- // for local variables table attributes
- int thenInitStateIndex = -1;
- int elseInitStateIndex = -1;
- int mergedInitStateIndex = -1;
-
- public IfStatement(
- Expression condition,
- Statement thenStatement,
- int s,
- int e) {
-
- this.condition = condition;
- this.thenStatement = thenStatement;
- sourceStart = s;
- sourceEnd = e;
- }
-
- public IfStatement(
- Expression condition,
- Statement thenStatement,
- Statement elseStatement,
- int s,
- int e) {
-
- this.condition = condition;
- this.thenStatement = thenStatement;
- this.elseStatement = elseStatement;
- sourceEnd = e;
- sourceStart = s;
- }
-
- public FlowInfo analyseCode(
- BlockScope currentScope,
- FlowContext flowContext,
- FlowInfo flowInfo) {
-
- FlowInfo thenFlowInfo, elseFlowInfo;
-
- // process the condition
- flowInfo = condition.analyseCode(currentScope, flowContext, flowInfo);
-
- // process the THEN part
- if (thenStatement == null) {
- thenFlowInfo = flowInfo.initsWhenTrue();
- } else {
- Constant cst;
- thenFlowInfo =
- ((((cst = condition.constant) != NotAConstant)
- && (cst.booleanValue() == false))
- || (((cst = condition.conditionalConstant()) != NotAConstant)
- && (cst.booleanValue() == false)))
- ? (flowInfo.initsWhenTrue().copy().markAsFakeReachable(true))
- : flowInfo.initsWhenTrue().copy();
- // Save info for code gen
- thenInitStateIndex =
- currentScope.methodScope().recordInitializationStates(thenFlowInfo);
- if (!thenFlowInfo.complainIfUnreachable(thenStatement, currentScope)) {
- thenFlowInfo =
- thenStatement.analyseCode(currentScope, flowContext, thenFlowInfo);
- }
- };
- // optimizing the jump around the ELSE part
- thenExit = (thenFlowInfo == FlowInfo.DeadEnd) || thenFlowInfo.isFakeReachable();
-
- // process the ELSE part
- if (elseStatement == null) {
- elseFlowInfo = flowInfo.initsWhenFalse();
- } else {
- Constant cst;
- elseFlowInfo =
- ((((cst = condition.constant) != NotAConstant) && (cst.booleanValue() == true))
- || (((cst = condition.conditionalConstant()) != NotAConstant)
- && (cst.booleanValue() == true)))
- ? (flowInfo.initsWhenFalse().copy().markAsFakeReachable(true))
- : flowInfo.initsWhenFalse().copy();
- // Save info for code gen
- elseInitStateIndex =
- currentScope.methodScope().recordInitializationStates(elseFlowInfo);
- if (!elseFlowInfo.complainIfUnreachable(elseStatement, currentScope)) {
- elseFlowInfo =
- elseStatement.analyseCode(currentScope, flowContext, elseFlowInfo);
- }
- }
-
- // merge THEN & ELSE initializations
- FlowInfo mergedInfo;
- if ((condition.constant != NotAConstant)
- && (condition.constant.booleanValue() == true)) {
- // IF (TRUE)
- if (thenExit) {
- mergedInfo = elseFlowInfo.markAsFakeReachable(true);
- mergedInitStateIndex =
- currentScope.methodScope().recordInitializationStates(mergedInfo);
- return mergedInfo;
- } else {
- mergedInitStateIndex =
- currentScope.methodScope().recordInitializationStates(thenFlowInfo);
- return thenFlowInfo;
- }
- } else {
- // IF (FALSE)
- if ((condition.constant != NotAConstant)
- && (condition.constant.booleanValue() == false)) {
- if (elseFlowInfo.isDeadEnd()) {
- mergedInfo = thenFlowInfo.markAsFakeReachable(true);
- mergedInitStateIndex =
- currentScope.methodScope().recordInitializationStates(mergedInfo);
- return mergedInfo;
- } else {
- mergedInitStateIndex =
- currentScope.methodScope().recordInitializationStates(elseFlowInfo);
- return elseFlowInfo;
- }
- }
- }
- mergedInfo = thenFlowInfo.mergedWith(elseFlowInfo.unconditionalInits());
- mergedInitStateIndex =
- currentScope.methodScope().recordInitializationStates(mergedInfo);
- return mergedInfo;
- }
-
- /**
- * If code generation
- *
- * @param currentScope org.eclipse.jdt.internal.compiler.lookup.BlockScope
- * @param codeStream org.eclipse.jdt.internal.compiler.codegen.CodeStream
- */
- public void generateCode(BlockScope currentScope, CodeStream codeStream) {
-
- if ((bits & IsReachableMASK) == 0) {
- return;
- }
- int pc = codeStream.position;
- Label endifLabel = new Label(codeStream);
-
- // optimizing the then/else part code gen
- Constant cst, condCst;
- boolean hasThenPart =
- !((((cst = condition.constant) != NotAConstant)
- && (cst.booleanValue() == false))
- || (thenStatement == null)
- || (thenStatement.isEmptyBlock())
- || (((condCst = condition.conditionalConstant()) != NotAConstant)
- && (condCst.booleanValue() == false)));
- boolean hasElsePart =
- !(((cst != NotAConstant) && (cst.booleanValue() == true))
- || (elseStatement == null)
- || (elseStatement.isEmptyBlock())
- || (((condCst = condition.conditionalConstant()) != NotAConstant)
- && (condCst.booleanValue() == true)));
-
- if (hasThenPart) {
- Label falseLabel;
- // generate boolean condition
- condition.generateOptimizedBoolean(
- currentScope,
- codeStream,
- null,
- (falseLabel = new Label(codeStream)),
- true);
- // May loose some local variable initializations : affecting the local variable attributes
- if (thenInitStateIndex != -1) {
- codeStream.removeNotDefinitelyAssignedVariables(
- currentScope,
- thenInitStateIndex);
- codeStream.addDefinitelyAssignedVariables(currentScope, thenInitStateIndex);
- }
- // generate then statement
- thenStatement.generateCode(currentScope, codeStream);
- // jump around the else statement
- if (hasElsePart && !thenExit) {
- thenStatement.branchChainTo(endifLabel);
- int position = codeStream.position;
- codeStream.goto_(endifLabel);
- codeStream.updateLastRecordedEndPC(position);
- //goto is tagged as part of the thenAction block
- }
- falseLabel.place();
- } else {
- if (hasElsePart) {
- // generate boolean condition
- condition.generateOptimizedBoolean(
- currentScope,
- codeStream,
- endifLabel,
- null,
- true);
- } else {
- // generate condition side-effects
- condition.generateCode(currentScope, codeStream, false);
- codeStream.recordPositionsFrom(pc, this.sourceStart);
- }
- }
- // generate else statement
- if (hasElsePart) {
- // May loose some local variable initializations : affecting the local variable attributes
- if (elseInitStateIndex != -1) {
- codeStream.removeNotDefinitelyAssignedVariables(
- currentScope,
- elseInitStateIndex);
- codeStream.addDefinitelyAssignedVariables(currentScope, elseInitStateIndex);
- }
- elseStatement.generateCode(currentScope, codeStream);
- }
- endifLabel.place();
- // May loose some local variable initializations : affecting the local variable attributes
- if (mergedInitStateIndex != -1) {
- codeStream.removeNotDefinitelyAssignedVariables(
- currentScope,
- mergedInitStateIndex);
- }
- codeStream.recordPositionsFrom(pc, this.sourceStart);
- }
-
- public void resolve(BlockScope scope) {
-
- TypeBinding type = condition.resolveTypeExpecting(scope, BooleanBinding);
- condition.implicitWidening(type, type);
- if (thenStatement != null)
- thenStatement.resolve(scope);
- if (elseStatement != null)
- elseStatement.resolve(scope);
- }
-
- public String toString(int tab) {
-
- String inFront, s = tabString(tab);
- inFront = s;
- s = s + "if (" + condition.toStringExpression() + ") \n"; //$NON-NLS-1$ //$NON-NLS-2$
- s = s + thenStatement.toString(tab + 2) + ";"; //$NON-NLS-1$
- if (elseStatement != null)
- s = s + "\n" + inFront + "else\n" + elseStatement.toString(tab + 2) + ";"; //$NON-NLS-2$ //$NON-NLS-1$ //$NON-NLS-3$
- return s;
- }
-
- public void traverse(
- IAbstractSyntaxTreeVisitor visitor,
- BlockScope blockScope) {
- if (visitor.visit(this, blockScope)) {
- condition.traverse(visitor, blockScope);
- if (thenStatement != null)
- thenStatement.traverse(visitor, blockScope);
- if (elseStatement != null)
- elseStatement.traverse(visitor, blockScope);
- }
- visitor.endVisit(this, blockScope);
- }
-}
\ No newline at end of file
+ public Expression condition;
+ public Statement statement;
+ public ElseIf[] elseifs;
+ public Else els;
+
+ /**
+ * Create a new If statement.
+ * @param condition the condition
+ * @param statement a statement or a block of statements
+ * @param elseifs the elseifs
+ * @param els the else (or null)
+ * @param sourceStart the starting position
+ * @param sourceEnd the ending offset
+ */
+ public IfStatement(final Expression condition,
+ final Statement statement,
+ final ElseIf[] elseifs,
+ final Else els,
+ final int sourceStart,
+ final int sourceEnd) {
+ super(sourceStart, sourceEnd);
+ this.condition = condition;
+ this.statement = statement;
+ this.elseifs = elseifs;
+ this.els = els;
+ }
+
+ /**
+ * Return the object into String.
+ * @param tab how many tabs (not used here
+ * @return a String
+ */
+ public String toString(final int tab) {
+ final StringBuffer buff = new StringBuffer(tabString(tab));
+ buff.append("if (");//$NON-NLS-1$
+ buff.append(condition.toStringExpression()).append(") ");//$NON-NLS-1$
+ if (statement != null) {
+ buff.append(statement.toString(tab + 1));
+ }
+ for (int i = 0; i < elseifs.length; i++) {
+ buff.append(elseifs[i].toString(tab + 1));
+ buff.append("\n");//$NON-NLS-1$
+ }
+ if (els != null) {
+ buff.append(els.toString(tab + 1));
+ buff.append("\n");//$NON-NLS-1$
+ }
+ return buff.toString();
+ }
+
+ /**
+ * Get the variables from outside (parameters, globals ...)
+ * @return the variables from outside
+ */
+ public List getOutsideVariable() {
+ final ArrayList list = new ArrayList();
+ list.addAll(condition.getOutsideVariable()); // todo: check if unuseful
+ if (statement != null) {
+ list.addAll(statement.getOutsideVariable());
+ }
+ for (int i = 0; i < elseifs.length; i++) {
+ list.addAll(elseifs[i].getOutsideVariable());
+ }
+ if (els != null) {
+ list.addAll(els.getOutsideVariable());
+ }
+ return list;
+ }
+
+ /**
+ * get the modified variables.
+ * @return the variables from we change value
+ */
+ public List getModifiedVariable() {
+ final ArrayList list = new ArrayList();
+ list.addAll(condition.getModifiedVariable());
+ if (statement != null) {
+ list.addAll(statement.getModifiedVariable());
+ }
+ for (int i = 0; i < elseifs.length; i++) {
+ list.addAll(elseifs[i].getModifiedVariable());
+ }
+ if (els != null) {
+ list.addAll(els.getModifiedVariable());
+ }
+ return list;
+ }
+
+ /**
+ * Get the variables used.
+ * @return the variables used
+ */
+ public List getUsedVariable() {
+ final ArrayList list = new ArrayList();
+ list.addAll(condition.getUsedVariable());
+ if (statement != null) {
+ list.addAll(statement.getUsedVariable());
+ }
+ for (int i = 0; i < elseifs.length; i++) {
+ list.addAll(elseifs[i].getUsedVariable());
+ }
+ if (els != null) {
+ list.addAll(els.getUsedVariable());
+ }
+ return list;
+ }
+}