+/*******************************************************************************
+ * 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;
-/**
- * @author Matthieu Casanova
- */
+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;
+
public class ForStatement extends Statement {
+
+ 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);
+ }
- public Statement[] initializations;
- public Expression condition;
- public Statement[] increments;
- public Statement action;
-
- public ForStatement(Statement[] initializations,
- Expression condition,
- Statement[] increments,
- Statement action,
- int sourceStart,
- int sourceEnd) {
- super(sourceStart, sourceEnd);
- this.initializations = initializations;
- this.condition = condition;
- this.increments = increments;
- this.action = action;
- }
-
- public String toString(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++) {
- //nice only with expressions
- buff.append(initializations[i].toString());
- 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].toString());
- 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( "\n").append(action.toString(tab + 1)); //$NON-NLS-1$
- return buff.toString();
- }
+ if (action != null)
+ action.traverse(visitor, scope);
+ }
+ visitor.endVisit(this, blockScope);
+ }
}