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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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
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 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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 *
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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.
/**
 * 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
/**
     * The number of the variable
     */
    int number = -1;

    
Some statistics
/**
     * Some statistics
     */
    int readcount;
    int writecount;

    
An indication of which block the variable comes from.
Helps identify uplevel references.
/**
     * 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'.
/**
     * 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.
/**
     * 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.
/**
     * The previous local variable, this list is used to build a nested
     * context of local variables.
     */
    LocalMember prev;

    
Constructor
/**
     * 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.
/**
     * 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.
/**
     * 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?
/**
     * Is this a proxy for the given field?
     */
    final MemberDefinition getMember() {
        return (name == idClass) ? accessPeer : null;
    }

    
Special checks
/**
     * 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.
/**
     * 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.
/**
     * 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.
/**
     * 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.
/**
     * 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().)
/**
     * 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
/**
     * 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
/**
     * Return value
     */
    public Node getValue(Environment env) {
        return (Expression)getValue();
    }

    
Value number for vsets, or -1 if none.
/**
     * Value number for vsets, or -1 if none.
     */
    public int getNumber(Context ctx) {
        return number;
    }
}