X-Git-Url: http://secure.phpeclipse.com diff --git a/net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/compiler/ast/DoStatement.java b/net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/compiler/ast/DoStatement.java index a6c2934..32dfabd 100644 --- a/net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/compiler/ast/DoStatement.java +++ b/net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/compiler/ast/DoStatement.java @@ -1,83 +1,206 @@ +/******************************************************************************* + * 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; -import java.util.List; +import net.sourceforge.phpdt.internal.compiler.ASTVisitor; +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.flow.LoopingFlowContext; +import net.sourceforge.phpdt.internal.compiler.impl.Constant; +import net.sourceforge.phpdt.internal.compiler.lookup.BlockScope; +import net.sourceforge.phpdt.internal.compiler.lookup.TypeBinding; -/** - * A do statement. - * - * @author Matthieu Casanova - */ -public final class DoStatement extends Statement { - - - /** The condition expression. */ - private final Expression condition; - /** The action of the while. (it could be a block) */ - private final Statement action; - - public DoStatement(final Expression condition, - final Statement action, - final int sourceStart, - final int sourceEnd) { - super(sourceStart, sourceEnd); - this.condition = condition; - this.action = action; - } - - /** - * Return the object into String. - * - * @param tab how many tabs (not used here - * @return a String - */ - public String toString(final int tab) { - final String conditionString = condition.toStringExpression(); - final StringBuffer buff; - if (action == null) { - buff = new StringBuffer(17 + tab + conditionString.length()); - buff.append("do ");//$NON-NLS-1$ - buff.append(" {} ;"); //$NON-NLS-1$ - } else { - final String actionString = action.toString(tab + 1); - buff = new StringBuffer(13 + conditionString.length() + actionString.length()); - buff.append("do ");//$NON-NLS-1$ - buff.append("\n");//$NON-NLS-1$ - buff.append(actionString); - } - buff.append(tabString(tab)); - buff.append(" while (");//$NON-NLS-1$ - buff.append(conditionString); - buff.append(")");//$NON-NLS-1$ - return buff.toString(); - } - - /** - * Get the variables from outside (parameters, globals ...) - * - * @param list the list where we will put variables - */ - public void getOutsideVariable(final List list) { - condition.getOutsideVariable(list); // todo: check if unuseful - action.getOutsideVariable(list); - } - - /** - * get the modified variables. - * - * @param list the list where we will put variables - */ - public void getModifiedVariable(final List list) { - condition.getModifiedVariable(list); - action.getModifiedVariable(list); - } - - /** - * Get the variables used. - * - * @param list the list where we will put variables - */ - public void getUsedVariable(final List list) { - condition.getUsedVariable(list); - action.getUsedVariable(list); - } +public class DoStatement extends Statement { + + public Expression condition; + public Statement action; + + private Label breakLabel, continueLabel; + + // for local variables table attributes + int mergedInitStateIndex = -1; + + public DoStatement(Expression condition, Statement action, int s, int e) { + + this.sourceStart = s; + this.sourceEnd = e; + this.condition = condition; + this.action = action; + } + + public FlowInfo analyseCode( + BlockScope currentScope, + FlowContext flowContext, + FlowInfo flowInfo) { + + breakLabel = new Label(); + continueLabel = new Label(); + LoopingFlowContext loopingContext = + new LoopingFlowContext( + flowContext, + this, + breakLabel, + continueLabel, + currentScope); + + Constant cst = condition.constant; + boolean isConditionTrue = cst != NotAConstant && cst.booleanValue() == true; + cst = condition.optimizedBooleanConstant(); + boolean isConditionOptimizedTrue = cst != NotAConstant && cst.booleanValue() == true; + boolean isConditionOptimizedFalse = cst != NotAConstant && cst.booleanValue() == false; + + int previousMode = flowInfo.reachMode(); + + if ((action != null) && !action.isEmptyBlock()) { + flowInfo = action.analyseCode(currentScope, loopingContext, flowInfo); + + // code generation can be optimized when no need to continue in the loop + if (!flowInfo.isReachable() && !loopingContext.initsOnContinue.isReachable()) { + continueLabel = null; + } + } + /* Reset reach mode, to address following scenario. + * final blank; + * do { if (true) break; else blank = 0; } while(false); + * blank = 1; // may be initialized already + */ + flowInfo.setReachMode(previousMode); + + flowInfo = + condition.analyseCode( + currentScope, + loopingContext, + (action == null + ? flowInfo + : (flowInfo.mergedWith(loopingContext.initsOnContinue)))); + if (!isConditionOptimizedFalse && continueLabel != null) { + loopingContext.complainOnFinalAssignmentsInLoop(currentScope, flowInfo); + } + + // infinite loop + FlowInfo mergedInfo; + if (isConditionTrue) { + mergedInfo = loopingContext.initsOnBreak; + if (!mergedInfo.isReachable()) mergedInfo.addPotentialInitializationsFrom(flowInfo.initsWhenFalse()); + } else { + // end of loop: either condition false or break + mergedInfo = + flowInfo.initsWhenFalse().unconditionalInits().mergedWith( + loopingContext.initsOnBreak); + if (isConditionOptimizedTrue && !loopingContext.initsOnBreak.isReachable()) { + mergedInfo.setReachMode(FlowInfo.UNREACHABLE); + } + } + mergedInitStateIndex = + currentScope.methodScope().recordInitializationStates(mergedInfo); + return mergedInfo; + } + + /** + * Do statement code generation + * + */ +// public void generateCode(BlockScope currentScope, CodeStream codeStream) { +// +// if ((bits & IsReachableMASK) == 0) { +// return; +// } +// int pc = codeStream.position; +// +// // labels management +// Label actionLabel = new Label(codeStream); +// actionLabel.place(); +// breakLabel.codeStream = codeStream; +// if (continueLabel != null) { +// continueLabel.codeStream = codeStream; +// } +// +// // generate action +// if (action != null) { +// action.generateCode(currentScope, codeStream); +// } +// // generate condition +// if (continueLabel != null) { +// continueLabel.place(); +// condition.generateOptimizedBoolean( +// currentScope, +// codeStream, +// actionLabel, +// null, +// true); +// } +// breakLabel.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 resetStateForCodeGeneration() { + if (this.breakLabel != null) { + this.breakLabel.resetStateForCodeGeneration(); + } + if (this.continueLabel != null) { + this.continueLabel.resetStateForCodeGeneration(); + } + } + + public void resolve(BlockScope scope) { + + TypeBinding type = condition.resolveTypeExpecting(scope, BooleanBinding); + condition.implicitWidening(type, type); + if (action != null) + action.resolve(scope); + } + public StringBuffer printStatement(int indent, StringBuffer output) { + + printIndent(indent, output).append("do"); //$NON-NLS-1$ + if (action == null) + output.append(" ;\n"); //$NON-NLS-1$ + else { + output.append('\n'); + action.printStatement(indent + 1, output).append('\n'); + } + output.append("while ("); //$NON-NLS-1$ + return condition.printExpression(0, output).append(");"); //$NON-NLS-1$ + } + public String toString(int tab) { + + String inFront, s = tabString(tab); + inFront = s; + s = s + "do"; //$NON-NLS-1$ + if (action == null) + s = s + " {}\n"; //$NON-NLS-1$ + else if (action instanceof Block) + s = s + "\n" + action.toString(tab + 1) + "\n"; //$NON-NLS-2$ //$NON-NLS-1$ + else + s = s + " {\n" + action.toString(tab + 1) + ";}\n"; //$NON-NLS-1$ //$NON-NLS-2$ + s = s + inFront + "while (" + condition.toStringExpression() + ")"; //$NON-NLS-1$ //$NON-NLS-2$ + return s; + } + + public void traverse(ASTVisitor visitor, BlockScope scope) { + + if (visitor.visit(this, scope)) { + if (action != null) { + action.traverse(visitor, scope); + } + condition.traverse(visitor, scope); + } + visitor.endVisit(this, scope); + } }