/*******************************************************************************
- * Copyright (c) 2000, 2001, 2002 International Business Machines Corp. and others.
+ * 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 v0.5
+ * 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-v05.html
+ * http://www.eclipse.org/legal/cpl-v10.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.*;
+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 DoStatement extends Statement {
public Expression condition;
+
public Statement action;
private Label breakLabel, continueLabel;
this.action = action;
}
- public FlowInfo analyseCode(
- BlockScope currentScope,
- FlowContext flowContext,
- FlowInfo flowInfo) {
+ 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 conditionConstant = condition.constant;
- Constant conditionalConstant = condition.conditionalConstant();
- boolean isFalseCondition =
- ((conditionConstant != NotAConstant)
- && (conditionConstant.booleanValue() == false))
- || ((conditionalConstant != NotAConstant)
- && (conditionalConstant.booleanValue() == false));
+ 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.copy());
-
- // code generation can be optimized when no need to continue in the loop
- if ((flowInfo == FlowInfo.DeadEnd) || flowInfo.isFakeReachable()) {
- if ((loopingContext.initsOnContinue == FlowInfo.DeadEnd)
- || loopingContext.initsOnContinue.isFakeReachable()) {
- continueLabel = null;
- } else {
- flowInfo = loopingContext.initsOnContinue; // for condition
- if (isFalseCondition) {
- // continueLabel = null; - cannot nil the label since may be targeted already by 'continue' statements
- } else {
- loopingContext.complainOnFinalAssignmentsInLoop(currentScope, flowInfo);
- }
- }
- } else {
- if (isFalseCondition) {
- // continueLabel = null; - cannot nil the label since may be targeted already by 'continue' statements
- } else {
- loopingContext.complainOnFinalAssignmentsInLoop(currentScope, flowInfo);
- }
+ 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;
}
}
- LoopingFlowContext condLoopContext;
- flowInfo =
- condition.analyseCode(
- currentScope,
- (condLoopContext =
- new LoopingFlowContext(flowContext, this, null, null, currentScope)),
- (action == null
- ? flowInfo
- : (flowInfo.mergedWith(loopingContext.initsOnContinue))));
- condLoopContext.complainOnFinalAssignmentsInLoop(currentScope, flowInfo);
+ /*
+ * 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 ((condition.constant != NotAConstant)
- && (condition.constant.booleanValue() == true)) {
+ if (isConditionTrue) {
mergedInfo = loopingContext.initsOnBreak;
- mergedInitStateIndex =
- currentScope.methodScope().recordInitializationStates(mergedInfo);
- return mergedInfo;
+ 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);
+ }
}
-
- // end of loop: either condition false or break
- mergedInfo =
- flowInfo.initsWhenFalse().unconditionalInits().mergedWith(
- loopingContext.initsOnBreak);
- mergedInitStateIndex =
- currentScope.methodScope().recordInitializationStates(mergedInfo);
+ 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);
+ // 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();
}
- // generate condition
- if (continueLabel != null) {
- continueLabel.place();
- condition.generateOptimizedBoolean(
- currentScope,
- codeStream,
- actionLabel,
- null,
- true);
+ if (this.continueLabel != null) {
+ this.continueLabel.resetStateForCodeGeneration();
}
- 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() {
-
- this.breakLabel.resetStateForCodeGeneration();
- this.continueLabel.resetStateForCodeGeneration();
}
public void resolve(BlockScope scope) {
- TypeBinding type = condition.resolveTypeExpecting(scope, BooleanBinding);
+ 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);
return s;
}
- public void traverse(IAbstractSyntaxTreeVisitor visitor, BlockScope scope) {
+ public void traverse(ASTVisitor visitor, BlockScope scope) {
if (visitor.visit(this, scope)) {
if (action != null) {
}
visitor.endVisit(this, scope);
}
-}
\ No newline at end of file
+}