+++ /dev/null
-/*******************************************************************************
- * 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;
-
-//dedicated treatment for the ||
-public class OR_OR_Expression extends BinaryExpression {
-
- int rightInitStateIndex = -1;
- int mergedInitStateIndex = -1;
-
- public OR_OR_Expression(Expression left, Expression right, int operator) {
- super(left, right, operator);
- }
-
- public FlowInfo analyseCode(
- BlockScope currentScope,
- FlowContext flowContext,
- FlowInfo flowInfo) {
-
- Constant opConstant = left.conditionalConstant();
- if (opConstant != NotAConstant) {
- if (opConstant.booleanValue() == false) {
- // FALSE || anything
- // need to be careful of scenario:
- // (x || y) || !z, if passing the left info to the right, it would be swapped by the !
- FlowInfo mergedInfo = left.analyseCode(currentScope, flowContext, flowInfo).unconditionalInits();
- mergedInfo = right.analyseCode(currentScope, flowContext, mergedInfo);
- mergedInitStateIndex =
- currentScope.methodScope().recordInitializationStates(mergedInfo);
- return mergedInfo;
- }
- }
- FlowInfo leftInfo, rightInfo;
- leftInfo = left.analyseCode(currentScope, flowContext, flowInfo);
-
- // need to be careful of scenario:
- // (x || y) || !z, if passing the left info to the right, it would be swapped by the !
- rightInfo = leftInfo.initsWhenFalse().unconditionalInits().copy();
- if (opConstant != NotAConstant && opConstant.booleanValue() == true) rightInfo.markAsFakeReachable(true);
-
- rightInitStateIndex =
- currentScope.methodScope().recordInitializationStates(rightInfo);
- rightInfo = right.analyseCode(currentScope, flowContext, rightInfo);
- FlowInfo mergedInfo = FlowInfo.conditional(
- // merging two true initInfos for such a negative case: if ((t && (b = t)) || f) r = b; // b may not have been initialized
- leftInfo.initsWhenTrue().copy().unconditionalInits().mergedWith(
- rightInfo.initsWhenTrue().copy().unconditionalInits()),
- rightInfo.initsWhenFalse().copy());
- mergedInitStateIndex =
- currentScope.methodScope().recordInitializationStates(mergedInfo);
- return mergedInfo;
- }
-
- /**
- * Code generation for a binary operation
- *
- * @param currentScope org.eclipse.jdt.internal.compiler.lookup.BlockScope
- * @param codeStream org.eclipse.jdt.internal.compiler.codegen.CodeStream
- * @param valueRequired boolean
- */
- public void generateCode(
- BlockScope currentScope,
- CodeStream codeStream,
- boolean valueRequired) {
- int pc = codeStream.position;
- Label falseLabel, endLabel;
- if (constant != Constant.NotAConstant) {
- if (valueRequired)
- codeStream.generateConstant(constant, implicitConversion);
- codeStream.recordPositionsFrom(pc, this.sourceStart);
- return;
- }
- bits |= OnlyValueRequiredMASK;
- generateOptimizedBoolean(
- currentScope,
- codeStream,
- null,
- (falseLabel = new Label(codeStream)),
- valueRequired);
- /* improving code gen for such a case: boolean b = i < 0 || true;
- * since the label has never been used, we have the inlined value on the stack. */
- if (falseLabel.hasForwardReferences()) {
- if (valueRequired) {
- codeStream.iconst_1();
- if ((bits & ValueForReturnMASK) != 0) {
- codeStream.ireturn();
- falseLabel.place();
- codeStream.iconst_0();
- } else {
- codeStream.goto_(endLabel = new Label(codeStream));
- codeStream.decrStackSize(1);
- falseLabel.place();
- codeStream.iconst_0();
- endLabel.place();
- }
- } else {
- falseLabel.place();
- }
- }
- if (valueRequired) {
- codeStream.generateImplicitConversion(implicitConversion);
- }
- codeStream.recordPositionsFrom(pc, this.sourceStart);
- }
-
- /**
- * Boolean operator code generation
- * Optimized operations are: ||
- */
- public void generateOptimizedBoolean(
- BlockScope currentScope,
- CodeStream codeStream,
- Label trueLabel,
- Label falseLabel,
- boolean valueRequired) {
- if ((constant != Constant.NotAConstant) && (constant.typeID() == T_boolean)) {
- super.generateOptimizedBoolean(currentScope, codeStream, trueLabel, falseLabel, valueRequired);
- return;
- }
- int pc = codeStream.position;
- Constant condConst;
- if ((condConst = left.conditionalConstant()) != NotAConstant) {
- if (condConst.booleanValue() == true) {
- // <something equivalent to true> || x
- left.generateOptimizedBoolean(
- currentScope,
- codeStream,
- trueLabel,
- falseLabel,
- false);
- if (valueRequired) {
- if ((bits & OnlyValueRequiredMASK) != 0) {
- codeStream.iconst_1();
- } else {
- if (trueLabel != null) {
- codeStream.goto_(trueLabel);
- }
- }
- }
- } else {
- // <something equivalent to false> || x
- left.generateOptimizedBoolean(
- currentScope,
- codeStream,
- trueLabel,
- falseLabel,
- false);
- if (rightInitStateIndex != -1) {
- codeStream.addDefinitelyAssignedVariables(currentScope, rightInitStateIndex);
- }
- if ((bits & OnlyValueRequiredMASK) != 0) {
- right.generateCode(currentScope, codeStream, valueRequired);
- } else {
- right.generateOptimizedBoolean(
- currentScope,
- codeStream,
- trueLabel,
- falseLabel,
- valueRequired);
- }
- }
- codeStream.recordPositionsFrom(pc, this.sourceStart);
- if (mergedInitStateIndex != -1) {
- codeStream.removeNotDefinitelyAssignedVariables(
- currentScope,
- mergedInitStateIndex);
- }
- return;
- }
- if ((condConst = right.conditionalConstant()) != NotAConstant) {
- if (condConst.booleanValue() == true) {
- // x || <something equivalent to true>
- left.generateOptimizedBoolean(
- currentScope,
- codeStream,
- trueLabel,
- falseLabel,
- false);
- if (rightInitStateIndex != -1) {
- codeStream.addDefinitelyAssignedVariables(currentScope, rightInitStateIndex);
- }
- right.generateOptimizedBoolean(
- currentScope,
- codeStream,
- trueLabel,
- falseLabel,
- false);
- if (valueRequired) {
- if ((bits & OnlyValueRequiredMASK) != 0) {
- codeStream.iconst_1();
- } else {
- if (trueLabel != null) {
- codeStream.goto_(trueLabel);
- }
- }
- }
- } else {
- // x || <something equivalent to false>
- if ((bits & OnlyValueRequiredMASK) != 0) {
- left.generateCode(currentScope, codeStream, valueRequired);
- } else {
- left.generateOptimizedBoolean(
- currentScope,
- codeStream,
- trueLabel,
- falseLabel,
- valueRequired);
- }
- if (rightInitStateIndex != -1) {
- codeStream.addDefinitelyAssignedVariables(currentScope, rightInitStateIndex);
- }
- right.generateOptimizedBoolean(
- currentScope,
- codeStream,
- trueLabel,
- falseLabel,
- false);
- }
- codeStream.recordPositionsFrom(pc, this.sourceStart);
- if (mergedInitStateIndex != -1) {
- codeStream.removeNotDefinitelyAssignedVariables(
- currentScope,
- mergedInitStateIndex);
- }
- return;
- }
- // default case
- if (falseLabel == null) {
- if (trueLabel != null) {
- // implicit falling through the FALSE case
- left.generateOptimizedBoolean(currentScope, codeStream, trueLabel, null, true);
- right.generateOptimizedBoolean(
- currentScope,
- codeStream,
- trueLabel,
- null,
- valueRequired);
- }
- } else {
- // implicit falling through the TRUE case
- if (trueLabel == null) {
- Label internalTrueLabel = new Label(codeStream);
- left.generateOptimizedBoolean(
- currentScope,
- codeStream,
- internalTrueLabel,
- null,
- true);
- if (rightInitStateIndex != -1) {
- codeStream.addDefinitelyAssignedVariables(currentScope, rightInitStateIndex);
- }
- right.generateOptimizedBoolean(
- currentScope,
- codeStream,
- null,
- falseLabel,
- valueRequired);
- internalTrueLabel.place();
- } else {
- // no implicit fall through TRUE/FALSE --> should never occur
- }
- }
- codeStream.recordPositionsFrom(pc, this.sourceStart);
- if (mergedInitStateIndex != -1) {
- codeStream.removeNotDefinitelyAssignedVariables(
- currentScope,
- mergedInitStateIndex);
- }
- }
-
- public boolean isCompactableOperation() {
- return false;
- }
-
- public void traverse(IAbstractSyntaxTreeVisitor visitor, BlockScope scope) {
- if (visitor.visit(this, scope)) {
- left.traverse(visitor, scope);
- right.traverse(visitor, scope);
- }
- visitor.endVisit(this, scope);
- }
-}
\ No newline at end of file
git://git.phpeclipse.com / phpeclipse.git / blobdiff