+/*******************************************************************************
+ * 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 java.util.ArrayList;
+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 For statement.
- * for(initializations;condition;increments) action
- * @author Matthieu Casanova
- */
public class ForStatement extends Statement {
- /** the initializations. */
- public Expression[] initializations;
-
- /** the condition. */
- public Expression condition;
- /** the increments. */
- public Expression[] increments;
-
- public Statement action;
-
- public ForStatement(final Expression[] initializations,
- final Expression condition,
- final Expression[] increments,
- final Statement action,
- final int sourceStart,
- final int sourceEnd) {
- super(sourceStart, sourceEnd);
- this.initializations = initializations;
- this.condition = condition;
- this.increments = increments;
- this.action = action;
- }
-
- public String toString(final int tab) {
- final StringBuffer buff = new StringBuffer(tabString(tab));
- buff.append("for ("); //$NON-NLS-1$
- //inits
- if (initializations != null) {
- for (int i = 0; i < initializations.length; i++) {
- buff.append(initializations[i].toStringExpression());
- if (i != (initializations.length - 1))
- buff.append(" , "); //$NON-NLS-1$
- }
- }
- buff.append("; "); //$NON-NLS-1$
- //cond
- if (condition != null) {
- buff.append(condition.toStringExpression());
- }
- buff.append("; "); //$NON-NLS-1$
- //updates
- if (increments != null) {
- for (int i = 0; i < increments.length; i++) {
- //nice only with expressions
- buff.append(increments[i].toStringExpression());
- if (i != (increments.length - 1))
- buff.append(" , "); //$NON-NLS-1$
- }
- }
- buff.append(") "); //$NON-NLS-1$
- //block
- if (action == null)
- buff.append("{}"); //$NON-NLS-1$
- else
- buff.append(action.toString(tab + 1)); //$NON-NLS-1$
- 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());
- list.addAll(action.getOutsideVariable());
- for (int i = 0; i < initializations.length; i++) {
- list.addAll(initializations[i].getOutsideVariable());
- }
- for (int i = 0; i < increments.length; i++) {
- list.addAll(increments[i].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());
- list.addAll(action.getModifiedVariable());
- for (int i = 0; i < initializations.length; i++) {
- list.addAll(initializations[i].getModifiedVariable());
- }
- for (int i = 0; i < increments.length; i++) {
- list.addAll(increments[i].getModifiedVariable());
- }
- return list;
- }
-
- /**
- * Get the variables used.
- * @return the variables used
- */
- public List getUsedVariable() {
- final ArrayList list = new ArrayList();
- list.addAll(condition.getUsedVariable());
- list.addAll(action.getUsedVariable());
- for (int i = 0; i < initializations.length; i++) {
- list.addAll(initializations[i].getUsedVariable());
- }
- for (int i = 0; i < increments.length; i++) {
- list.addAll(increments[i].getUsedVariable());
- }
- return list;
- }
+ public Statement[] initializations;
+
+ public Expression condition;
+
+ public Statement[] increments;
+
+ public Statement action;
+
+ // when there is no local declaration, there is no need of a new scope
+ // scope is positionned either to a new scope, or to the "upper"scope (see
+ // resolveType)
+ public boolean neededScope;
+
+ public BlockScope scope;
+
+ private Label breakLabel, continueLabel;
+
+ // for local variables table attributes
+ int preCondInitStateIndex = -1;
+
+ int condIfTrueInitStateIndex = -1;
+
+ int mergedInitStateIndex = -1;
+
+ public ForStatement(Statement[] initializations, Expression condition,
+ Statement[] increments, Statement action, boolean neededScope,
+ int s, int e) {
+
+ this.sourceStart = s;
+ this.sourceEnd = e;
+ this.initializations = initializations;
+ this.condition = condition;
+ this.increments = increments;
+ this.action = action;
+ this.neededScope = neededScope;
+ }
+
+ public FlowInfo analyseCode(BlockScope currentScope,
+ FlowContext flowContext, FlowInfo flowInfo) {
+
+ breakLabel = new Label();
+ continueLabel = new Label();
+
+ // process the initializations
+ if (initializations != null) {
+ int count = initializations.length, i = 0;
+ while (i < count) {
+ flowInfo = initializations[i++].analyseCode(scope, flowContext,
+ flowInfo);
+ }
+ }
+ preCondInitStateIndex = currentScope.methodScope()
+ .recordInitializationStates(flowInfo);
+
+ Constant cst = this.condition == null ? null : this.condition.constant;
+ boolean isConditionTrue = cst == null
+ || (cst != NotAConstant && cst.booleanValue() == true);
+ boolean isConditionFalse = cst != null
+ && (cst != NotAConstant && cst.booleanValue() == false);
+
+ cst = this.condition == null ? null : this.condition
+ .optimizedBooleanConstant();
+ boolean isConditionOptimizedTrue = cst == null
+ || (cst != NotAConstant && cst.booleanValue() == true);
+ boolean isConditionOptimizedFalse = cst != null
+ && (cst != NotAConstant && cst.booleanValue() == false);
+
+ // process the condition
+ LoopingFlowContext condLoopContext = null;
+ if (condition != null) {
+ if (!isConditionTrue) {
+ flowInfo = condition.analyseCode(scope,
+ (condLoopContext = new LoopingFlowContext(flowContext,
+ this, null, null, scope)), flowInfo);
+ }
+ }
+
+ // process the action
+ LoopingFlowContext loopingContext;
+ FlowInfo actionInfo;
+ if (action == null) {
+ // || (action.isEmptyBlock() &&
+ // currentScope.environment().options.complianceLevel <=
+ // CompilerOptions.JDK1_3)) {
+ if (condLoopContext != null)
+ condLoopContext.complainOnFinalAssignmentsInLoop(scope,
+ flowInfo);
+ if (isConditionTrue) {
+ return FlowInfo.DEAD_END;
+ } else {
+ if (isConditionFalse) {
+ continueLabel = null; // for(;false;p());
+ }
+ actionInfo = flowInfo.initsWhenTrue().copy();
+ loopingContext = new LoopingFlowContext(flowContext, this,
+ breakLabel, continueLabel, scope);
+ }
+ } else {
+ loopingContext = new LoopingFlowContext(flowContext, this,
+ breakLabel, continueLabel, scope);
+ FlowInfo initsWhenTrue = flowInfo.initsWhenTrue();
+ condIfTrueInitStateIndex = currentScope.methodScope()
+ .recordInitializationStates(initsWhenTrue);
+
+ if (isConditionFalse) {
+ actionInfo = FlowInfo.DEAD_END;
+ } else {
+ actionInfo = initsWhenTrue.copy();
+ if (isConditionOptimizedFalse) {
+ actionInfo.setReachMode(FlowInfo.UNREACHABLE);
+ }
+ }
+ if (!actionInfo.complainIfUnreachable(action, scope, false)) {
+ actionInfo = action.analyseCode(scope, loopingContext,
+ actionInfo);
+ }
+
+ // code generation can be optimized when no need to continue in the
+ // loop
+ if (!actionInfo.isReachable()
+ && !loopingContext.initsOnContinue.isReachable()) {
+ continueLabel = null;
+ } else {
+ if (condLoopContext != null)
+ condLoopContext.complainOnFinalAssignmentsInLoop(scope,
+ flowInfo);
+ loopingContext.complainOnFinalAssignmentsInLoop(scope,
+ actionInfo);
+ actionInfo = actionInfo
+ .mergedWith(loopingContext.initsOnContinue
+ .unconditionalInits());
+ // for increments
+ }
+ }
+ if ((continueLabel != null) && (increments != null)) {
+ LoopingFlowContext loopContext = new LoopingFlowContext(
+ flowContext, this, null, null, scope);
+ int i = 0, count = increments.length;
+ while (i < count)
+ actionInfo = increments[i++].analyseCode(scope, loopContext,
+ actionInfo);
+ loopContext.complainOnFinalAssignmentsInLoop(scope, actionInfo);
+ }
+
+ // infinite loop
+ FlowInfo mergedInfo;
+ if (isConditionOptimizedTrue) {
+ mergedInitStateIndex = currentScope.methodScope()
+ .recordInitializationStates(
+ mergedInfo = loopingContext.initsOnBreak);
+ return mergedInfo;
+ }
+
+ // end of loop: either condition false or break
+ mergedInfo = flowInfo.initsWhenFalse().unconditionalInits().mergedWith(
+ loopingContext.initsOnBreak.unconditionalInits());
+ if (isConditionOptimizedTrue && continueLabel == null) {
+ mergedInfo.setReachMode(FlowInfo.UNREACHABLE);
+ }
+ mergedInitStateIndex = currentScope.methodScope()
+ .recordInitializationStates(mergedInfo);
+ return mergedInfo;
+ }
+
+ /**
+ * For statement code generation
+ *
+ * @param currentScope
+ * net.sourceforge.phpdt.internal.compiler.lookup.BlockScope
+ * @param codeStream
+ * net.sourceforge.phpdt.internal.compiler.codegen.CodeStream
+ */
+ // public void generateCode(BlockScope currentScope, CodeStream codeStream)
+ // {
+ //
+ // if ((bits & IsReachableMASK) == 0) {
+ // return;
+ // }
+ // int pc = codeStream.position;
+ //
+ // // generate the initializations
+ // if (initializations != null) {
+ // for (int i = 0, max = initializations.length; i < max; i++) {
+ // initializations[i].generateCode(scope, codeStream);
+ // }
+ // }
+ //
+ // // label management
+ // Label actionLabel = new Label(codeStream);
+ // Label conditionLabel = new Label(codeStream);
+ // breakLabel.codeStream = codeStream;
+ // if (continueLabel != null) {
+ // continueLabel.codeStream = codeStream;
+ // }
+ // // jump over the actionBlock
+ // if ((condition != null)
+ // && (condition.constant == NotAConstant)
+ // && !((action == null || action.isEmptyBlock()) && (increments == null)))
+ // {
+ // int jumpPC = codeStream.position;
+ // codeStream.goto_(conditionLabel);
+ // codeStream.recordPositionsFrom(jumpPC, condition.sourceStart);
+ // }
+ // // generate the loop action
+ // actionLabel.place();
+ // if (action != null) {
+ // // Required to fix 1PR0XVS: LFRE:WINNT - Compiler: variable table for
+ // method appears incorrect
+ // if (condIfTrueInitStateIndex != -1) {
+ // // insert all locals initialized inside the condition into the action
+ // generated prior to the condition
+ // codeStream.addDefinitelyAssignedVariables(
+ // currentScope,
+ // condIfTrueInitStateIndex);
+ // }
+ // action.generateCode(scope, codeStream);
+ // }
+ // // continuation point
+ // if (continueLabel != null) {
+ // continueLabel.place();
+ // // generate the increments for next iteration
+ // if (increments != null) {
+ // for (int i = 0, max = increments.length; i < max; i++) {
+ // increments[i].generateCode(scope, codeStream);
+ // }
+ // }
+ // }
+ //
+ // // May loose some local variable initializations : affecting the local
+ // variable attributes
+ // if (preCondInitStateIndex != -1) {
+ // codeStream.removeNotDefinitelyAssignedVariables(
+ // currentScope,
+ // preCondInitStateIndex);
+ // }
+ //
+ // // generate the condition
+ // conditionLabel.place();
+ // if ((condition != null) && (condition.constant == NotAConstant)) {
+ // condition.generateOptimizedBoolean(scope, codeStream, actionLabel, null,
+ // true);
+ // } else {
+ // if (continueLabel != null) {
+ // codeStream.goto_(actionLabel);
+ // }
+ // }
+ // breakLabel.place();
+ //
+ // // May loose some local variable initializations : affecting the local
+ // variable attributes
+ // if (neededScope) {
+ // codeStream.exitUserScope(scope);
+ // }
+ // 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 StringBuffer printStatement(int tab, StringBuffer output) {
+
+ printIndent(tab, output).append("for ("); //$NON-NLS-1$
+ // inits
+ if (initializations != null) {
+ for (int i = 0; i < initializations.length; i++) {
+ // nice only with expressions
+ if (i > 0)
+ output.append(", "); //$NON-NLS-1$
+ initializations[i].print(0, output);
+ }
+ }
+ output.append("; "); //$NON-NLS-1$
+ // cond
+ if (condition != null)
+ condition.printExpression(0, output);
+ output.append("; "); //$NON-NLS-1$
+ // updates
+ if (increments != null) {
+ for (int i = 0; i < increments.length; i++) {
+ if (i > 0)
+ output.append(", "); //$NON-NLS-1$
+ increments[i].print(0, output);
+ }
+ }
+ output.append(") "); //$NON-NLS-1$
+ // block
+ if (action == null)
+ output.append(';');
+ else {
+ output.append('\n');
+ action.printStatement(tab + 1, output); //$NON-NLS-1$
+ }
+ return output.append(';');
+ }
+
+ public void resolve(BlockScope upperScope) {
+
+ // use the scope that will hold the init declarations
+ scope = neededScope ? new BlockScope(upperScope) : upperScope;
+ if (initializations != null)
+ for (int i = 0, length = initializations.length; i < length; i++)
+ initializations[i].resolve(scope);
+ if (condition != null) {
+ TypeBinding type = condition.resolveTypeExpecting(scope,
+ BooleanBinding);
+ condition.implicitWidening(type, type);
+ }
+ if (increments != null)
+ for (int i = 0, length = increments.length; i < length; i++)
+ increments[i].resolve(scope);
+ if (action != null)
+ action.resolve(scope);
+ }
+
+ public String toString(int tab) {
+
+ String s = tabString(tab) + "for ("; //$NON-NLS-1$
+ if (!neededScope)
+ s = s
+ + " //--NO upperscope scope needed\n" + tabString(tab) + " "; //$NON-NLS-2$ //$NON-NLS-1$
+ // inits
+ if (initializations != null) {
+ for (int i = 0; i < initializations.length; i++) {
+ // nice only with expressions
+ s = s + initializations[i].toString(0);
+ if (i != (initializations.length - 1))
+ s = s + " , "; //$NON-NLS-1$
+ }
+ }
+ ;
+ s = s + "; "; //$NON-NLS-1$
+ // cond
+ if (condition != null)
+ s = s + condition.toStringExpression();
+ s = s + "; "; //$NON-NLS-1$
+ // updates
+ if (increments != null) {
+ for (int i = 0; i < increments.length; i++) {
+ // nice only with expressions
+ s = s + increments[i].toString(0);
+ if (i != (increments.length - 1))
+ s = s + " , "; //$NON-NLS-1$
+ }
+ }
+ ;
+ s = s + ") "; //$NON-NLS-1$
+ // block
+ if (action == null)
+ s = s + "{}"; //$NON-NLS-1$
+ else
+ s = s + "\n" + action.toString(tab + 1); //$NON-NLS-1$
+ return s;
+ }
+
+ public void traverse(ASTVisitor visitor, BlockScope blockScope) {
+
+ if (visitor.visit(this, blockScope)) {
+ if (initializations != null) {
+ int initializationsLength = initializations.length;
+ for (int i = 0; i < initializationsLength; i++)
+ initializations[i].traverse(visitor, scope);
+ }
+
+ if (condition != null)
+ condition.traverse(visitor, scope);
+
+ if (increments != null) {
+ int incrementsLength = increments.length;
+ for (int i = 0; i < incrementsLength; i++)
+ increments[i].traverse(visitor, scope);
+ }
+
+ if (action != null)
+ action.traverse(visitor, scope);
+ }
+ visitor.endVisit(this, blockScope);
+ }
}