/*
* Copyright 1994-2003 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package sun.tools.tree;
import sun.tools.java.*;
import sun.tools.tree.*;
import java.util.Vector;
/**
* A local Field
*
* WARNING: The contents of this source file are not part of any
* supported API. Code that depends on them does so at its own risk:
* they are subject to change or removal without notice.
*/
public
class LocalMember extends MemberDefinition {
/**
* The number of the variable
*/
int number = -1;
/**
* Some statistics
*/
int readcount;
int writecount;
/**
* An indication of which block the variable comes from.
* Helps identify uplevel references.
*/
int scopeNumber;
/**
* Return current nesting level, i.e., the value of 'scopeNumber'.
* Made public for the benefit of 'ClassDefinition.resolveName'.
*/
public int getScopeNumber() {
return scopeNumber;
}
/**
* Used by copyInline to record the original of this copy.
*/
LocalMember originalOfCopy;
/**
* The previous local variable, this list is used to build a nested
* context of local variables.
*/
LocalMember prev;
/**
* Constructor
*/
public LocalMember(long where, ClassDefinition clazz, int modifiers, Type type,
Identifier name) {
super(where, clazz, modifiers, type, name, null, null);
}
/**
* Constructor for a block-inner class.
*/
public LocalMember(ClassDefinition innerClass) {
super(innerClass);
// The class's "real" name is something like "foo$1$bar", but locally:
name = innerClass.getLocalName();
}
/**
* Constructor for a proxy to an instance or class variable.
*/
LocalMember(MemberDefinition field) {
this(0, null, 0, field.getType(), idClass);
// use this random slot to store the info:
accessPeer = field;
}
/**
* Is this a proxy for the given field?
*/
final MemberDefinition getMember() {
return (name == idClass) ? accessPeer : null;
}
/**
* Special checks
*/
public boolean isLocal() {
return true;
}
/**
* Make a copy of this field, which is an argument to a method
* or constructor. Arrange so that when occurrences of the field
* are encountered in an immediately following copyInline() operation,
* the expression nodes will replace the original argument by the
* fresh copy.
*/
public LocalMember copyInline(Context ctx) {
LocalMember copy = new LocalMember(where, clazz, modifiers, type, name);
copy.readcount = this.readcount;
copy.writecount = this.writecount;
copy.originalOfCopy = this;
// Make a temporary link from the original.
// It only stays valid through the next call to copyInline().
// (This means that recursive inlining won't work.)
// To stay honest, we mark these inline copies:
copy.addModifiers(M_LOCAL);
if (this.accessPeer != null
&& (this.accessPeer.getModifiers() & M_LOCAL) == 0) {
throw new CompilerError("local copyInline");
}
this.accessPeer = copy;
return copy;
}
/**
* Returns the previous result of copyInline(ctx).
* Must be called in the course of an Expression.copyInline()
* operation that immediately follows the LocalMember.copyInline().
* Return "this" if there is no such copy.
*/
public LocalMember getCurrentInlineCopy(Context ctx) {
MemberDefinition accessPeer = this.accessPeer;
if (accessPeer != null && (accessPeer.getModifiers() & M_LOCAL) != 0) {
LocalMember copy = (LocalMember)accessPeer;
return copy;
}
return this;
}
/**
* May inline copies of all the arguments of the given method.
*/
static public LocalMember[] copyArguments(Context ctx, MemberDefinition field) {
Vector v = field.getArguments();
LocalMember res[] = new LocalMember[v.size()];
v.copyInto(res);
for (int i = 0; i < res.length; i++) {
res[i] = res[i].copyInline(ctx);
}
return res;
}
/**
* Call this when finished with the result of a copyArguments() call.
*/
static public void doneWithArguments(Context ctx, LocalMember res[]) {
for (int i = 0; i < res.length; i++) {
if (res[i].originalOfCopy.accessPeer == res[i]) {
res[i].originalOfCopy.accessPeer = null;
}
}
}
/**
* Is this local variable's value stable and simple enough to be directly
* substituted for occurrences of the variable itself?
* (This decision is made by VarDeclarationStatement.inline().)
*/
public boolean isInlineable(Environment env, boolean fromFinal) {
return (getModifiers() & M_INLINEABLE) != 0;
}
/**
* Check if used
*/
public boolean isUsed() {
return (readcount != 0) || (writecount != 0);
}
// Used by class Context, only on members of MemberDefinition.available:
LocalMember getAccessVar() {
return (LocalMember)accessPeer;
}
void setAccessVar(LocalMember f) {
accessPeer = f;
}
// Used by class Context, only on "AccessVar" constructor args
MemberDefinition getAccessVarMember() {
return accessPeer;
}
void setAccessVarMember(MemberDefinition f) {
accessPeer = f;
}
/**
* Return value
*/
public Node getValue(Environment env) {
return (Expression)getValue();
}
/**
* Value number for vsets, or -1 if none.
*/
public int getNumber(Context ctx) {
return number;
}
}