| /******************************************************************************* |
| * Copyright (c) 2000, 2004 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 org.eclipse.jdt.internal.compiler.lookup; |
| |
| import org.eclipse.jdt.internal.compiler.ast.AbstractMethodDeclaration; |
| import org.eclipse.jdt.internal.compiler.ast.LocalDeclaration; |
| import org.eclipse.jdt.internal.compiler.ast.TypeDeclaration; |
| import org.eclipse.jdt.internal.compiler.impl.Constant; |
| import org.eclipse.jdt.internal.compiler.impl.ReferenceContext; |
| |
| public class LocalVariableBinding extends VariableBinding { |
| |
| public boolean isArgument; |
| public int resolvedPosition; // for code generation (position in method context) |
| |
| public static final int UNUSED = 0; |
| public static final int USED = 1; |
| public static final int FAKE_USED = 2; |
| public int useFlag; // for flow analysis (default is UNUSED) |
| |
| public BlockScope declaringScope; // back-pointer to its declaring scope |
| public LocalDeclaration declaration; // for source-positions |
| |
| public int[] initializationPCs; |
| public int initializationCount = 0; |
| |
| // for synthetic local variables |
| // if declaration slot is not positionned, the variable will not be listed in attribute |
| // note that the name of a variable should be chosen so as not to conflict with user ones (usually starting with a space char is all needed) |
| public LocalVariableBinding(char[] name, TypeBinding type, int modifiers, boolean isArgument) { |
| super(name, type, modifiers, isArgument ? Constant.NotAConstant : null); |
| this.isArgument = isArgument; |
| } |
| |
| // regular local variable or argument |
| public LocalVariableBinding(LocalDeclaration declaration, TypeBinding type, int modifiers, boolean isArgument) { |
| |
| this(declaration.name, type, modifiers, isArgument); |
| this.declaration = declaration; |
| } |
| |
| /* API |
| * Answer the receiver's binding type from Binding.BindingID. |
| */ |
| public final int kind() { |
| |
| return LOCAL; |
| } |
| |
| /* |
| * declaringUniqueKey # scopeIndex / varName |
| * p.X { void foo() { int local; } } --> Lp/X;.foo()V#1/local |
| */ |
| public char[] computeUniqueKey() { |
| StringBuffer buffer = new StringBuffer(); |
| |
| // declaring method or type |
| BlockScope scope = this.declaringScope; |
| MethodScope methodScope = scope instanceof MethodScope ? (MethodScope) scope : scope.enclosingMethodScope(); |
| ReferenceContext referenceContext = methodScope.referenceContext; |
| if (referenceContext instanceof AbstractMethodDeclaration) { |
| MethodBinding methodBinding = ((AbstractMethodDeclaration) referenceContext).binding; |
| if (methodBinding != null) { |
| buffer.append(methodBinding.computeUniqueKey()); |
| } |
| } else if (referenceContext instanceof TypeDeclaration) { |
| TypeBinding typeBinding = ((TypeDeclaration) referenceContext).binding; |
| if (typeBinding != null) { |
| buffer.append(typeBinding.computeUniqueKey()); |
| } |
| } |
| |
| // scope index |
| getScopeKey(scope, buffer); |
| |
| // variable name |
| buffer.append('#'); |
| buffer.append(this.name); |
| |
| int length = buffer.length(); |
| char[] uniqueKey = new char[length]; |
| buffer.getChars(0, length, uniqueKey, 0); |
| return uniqueKey; |
| } |
| |
| private void getScopeKey(BlockScope scope, StringBuffer buffer) { |
| int scopeIndex = scope.scopeIndex(); |
| if (scopeIndex != -1) { |
| getScopeKey((BlockScope)scope.parent, buffer); |
| buffer.append('#'); |
| buffer.append(scopeIndex); |
| } |
| } |
| |
| // Answer whether the variable binding is a secret variable added for code gen purposes |
| public boolean isSecret() { |
| |
| return declaration == null && !isArgument; |
| } |
| |
| public void recordInitializationEndPC(int pc) { |
| |
| if (initializationPCs[((initializationCount - 1) << 1) + 1] == -1) |
| initializationPCs[((initializationCount - 1) << 1) + 1] = pc; |
| } |
| |
| public void recordInitializationStartPC(int pc) { |
| |
| if (initializationPCs == null) return; |
| // optimize cases where reopening a contiguous interval |
| if ((initializationCount > 0) && (initializationPCs[ ((initializationCount - 1) << 1) + 1] == pc)) { |
| initializationPCs[ ((initializationCount - 1) << 1) + 1] = -1; // reuse previous interval (its range will be augmented) |
| } else { |
| int index = initializationCount << 1; |
| if (index == initializationPCs.length) { |
| System.arraycopy(initializationPCs, 0, (initializationPCs = new int[initializationCount << 2]), 0, index); |
| } |
| initializationPCs[index] = pc; |
| initializationPCs[index + 1] = -1; |
| initializationCount++; |
| } |
| } |
| |
| public String toString() { |
| |
| String s = super.toString(); |
| switch (useFlag){ |
| case USED: |
| s += "[pos: " + String.valueOf(resolvedPosition) + "]"; //$NON-NLS-2$ //$NON-NLS-1$ |
| break; |
| case UNUSED: |
| s += "[pos: unused]"; //$NON-NLS-1$ |
| break; |
| case FAKE_USED: |
| s += "[pos: fake_used]"; //$NON-NLS-1$ |
| break; |
| } |
| s += "[id:" + String.valueOf(id) + "]"; //$NON-NLS-2$ //$NON-NLS-1$ |
| if (initializationCount > 0) { |
| s += "[pc: "; //$NON-NLS-1$ |
| for (int i = 0; i < initializationCount; i++) { |
| if (i > 0) |
| s += ", "; //$NON-NLS-1$ |
| s += String.valueOf(initializationPCs[i << 1]) + "-" + ((initializationPCs[(i << 1) + 1] == -1) ? "?" : String.valueOf(initializationPCs[(i<< 1) + 1])); //$NON-NLS-2$ //$NON-NLS-1$ |
| } |
| s += "]"; //$NON-NLS-1$ |
| } |
| return s; |
| } |
| } |