/*

 * Copyright (c) 1994, 2003, Oracle and/or its affiliates. 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.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

package sun.tools.tree;

import sun.tools.java.*;

import sun.tools.asm.Assembler;

import sun.tools.asm.LocalVariable;

import java.io.PrintStream;

import java.util.Hashtable;

/**

 * 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 VarDeclarationStatement extends Statement {

    LocalMember field;

    Expression expr;

    /**

     * Constructor

     */

    public VarDeclarationStatement(long where, Expression expr) {

        super(VARDECLARATION, where);

        this.expr = expr;

    }

    public VarDeclarationStatement(long where, LocalMember field, Expression expr) {

        super(VARDECLARATION, where);

        this.field = field;

        this.expr = expr;

    }

    /**

     * Check statement

     */

    Vset checkDeclaration(Environment env, Context ctx, Vset vset, int mod, Type t, Hashtable<Object, Object> exp) {

        if (labels != null) {

            env.error(where, "declaration.with.label", labels[0]);

        }

        if (field != null) {

            if (ctx.getLocalClass(field.getName()) != null

                && field.isInnerClass()) {

                env.error(where, "local.class.redefined", field.getName());

            }

            ctx.declare(env, field);

            if (field.isInnerClass()) {

                ClassDefinition body = field.getInnerClass();

                try {

                    vset = body.checkLocalClass(env, ctx, vset,

                                                null, null, null);

                } catch (ClassNotFound ee) {

                    env.error(where, "class.not.found", ee.name, opNames[op]);

                }

                return vset;

            }

            vset.addVar(field.number);

            return (expr != null) ? expr.checkValue(env, ctx, vset, exp) : vset;

        }

        // Argument 'expr' is either an IdentifierExpression for a declaration of

        // the form 'type x' or an AssignmentExpression for a declaration of the

        // form 'type x = initvalue'.  Note that these expressions are treated

        // specially in this context, and don't have much connection to their ordinary

        // meaning.

        Expression e = expr;

        if (e.op == ASSIGN) {

            expr = ((AssignExpression)e).right;

            e = ((AssignExpression)e).left;

        } else {

            expr = null;

        }

        boolean declError = t.isType(TC_ERROR);

        while (e.op == ARRAYACCESS) {

            ArrayAccessExpression array = (ArrayAccessExpression)e;

            if (array.index != null) {

                env.error(array.index.where, "array.dim.in.type");

                declError = true;

            }

            e = array.right;

            t = Type.tArray(t);

        }

        if (e.op == IDENT) {

            Identifier id = ((IdentifierExpression)e).id;

            if (ctx.getLocalField(id) != null) {

                env.error(where, "local.redefined", id);

            }

            field = new LocalMember(e.where, ctx.field.getClassDefinition(), mod, t, id);

            ctx.declare(env, field);

            if (expr != null) {

                vset = expr.checkInitializer(env, ctx, vset, t, exp);

                expr = convert(env, ctx, t, expr);

                field.setValue(expr); // for the sake of non-blank finals

                if (field.isConstant()) {

                    // Keep in mind that isConstant() only means expressions

                    // that are constant according to the JLS.  They might

                    // not be either constants or evaluable (eg. 1/0).

                    field.addModifiers(M_INLINEABLE);

                }

                vset.addVar(field.number);

            } else if (declError) {

                vset.addVar(field.number);

            } else {

                vset.addVarUnassigned(field.number);

            }

            return vset;

        }

        env.error(e.where, "invalid.decl");

        return vset;

    }

    /**

     * Inline

     */

    public Statement inline(Environment env, Context ctx) {

        if (field.isInnerClass()) {

            ClassDefinition body = field.getInnerClass();

            body.inlineLocalClass(env);

            return null;

        }

        // Don't generate code for variable if unused and

        // optimization is on, whether or not debugging is on

        if (env.opt() && !field.isUsed()) {

            return new ExpressionStatement(where, expr).inline(env, ctx);

        }

        ctx.declare(env, field);

        if (expr != null) {

            expr = expr.inlineValue(env, ctx);

            field.setValue(expr); // for the sake of non-blank finals

            if (env.opt() && (field.writecount == 0)) {

                if (expr.op == IDENT) {

                    // This code looks like it tests whether a final variable

                    // is being initialized by an identifier expression.

                    // Then if the identifier is a local of the same method

                    // it makes the final variable eligible to be inlined.

                    // BUT: why isn't the local also checked to make sure

                    // it is itself final?  Unknown.

                    IdentifierExpression e = (IdentifierExpression)expr;

                    if (e.field.isLocal() && ((ctx = ctx.getInlineContext()) != null) &&

                        (((LocalMember)e.field).number < ctx.varNumber)) {

                        //System.out.println("FINAL IDENT = " + field + " in " + ctx.field);

                        field.setValue(expr);

                        field.addModifiers(M_INLINEABLE);

                        // The two lines below used to elide the declaration

                        // of inlineable variables, on the theory that there

                        // wouldn't be any references.  But this breaks the

                        // translation of nested classes, which might refer to

                        // the variable.

                        //expr = null;

                        //return null;

                    }

                }

                if (expr.isConstant() || (expr.op == THIS) || (expr.op == SUPER)) {

                    //System.out.println("FINAL = " + field + " in " + ctx.field);

                    field.setValue(expr);

                    field.addModifiers(M_INLINEABLE);

                    // The two lines below used to elide the declaration

                    // of inlineable variables, on the theory that there

                    // wouldn't be any references.  But this breaks the

                    // translation of nested classes, which might refer to

                    // the variable.  Fix for 4073244.

                    //expr = null;

                    //return null;

                }

            }

        }

        return this;

    }

    /**

     * Create a copy of the statement for method inlining

     */

    public Statement copyInline(Context ctx, boolean valNeeded) {

        VarDeclarationStatement s = (VarDeclarationStatement)clone();

        if (expr != null) {

            s.expr = expr.copyInline(ctx);

        }

        return s;

    }

    /**

     * The cost of inlining this statement

     */

    public int costInline(int thresh, Environment env, Context ctx) {

        if (field != null && field.isInnerClass()) {

            return thresh;      // don't copy classes...

        }

        return (expr != null) ? expr.costInline(thresh, env, ctx) : 0;

    }

    /**

     * Code

     */

    public void code(Environment env, Context ctx, Assembler asm) {

        if (expr != null && !expr.type.isType(TC_VOID)) {

            // The two lines of code directly following this comment used

            // to be in the opposite order.  They were switched so that

            // lines like the following:

            //

            //     int j = (j = 4);

            //

            // will compile correctly.  (Constructions like the above are

            // legal.  JLS 14.3.2 says that the scope of a local variable

            // includes its own initializer.)  It is important that we

            // declare `field' before we code `expr', because otherwise

            // situations can arise where `field' thinks it is assigned

            // a local variable slot that is, in actuality, assigned to

            // an entirely different variable.  (Bug id 4076729)

            ctx.declare(env, field);

            expr.codeValue(env, ctx, asm);

            asm.add(where, opc_istore + field.getType().getTypeCodeOffset(),

                    new LocalVariable(field, field.number));

        } else {

            ctx.declare(env, field);

            if (expr != null) {

                // an initial side effect, rather than an initial value

                expr.code(env, ctx, asm);

            }

        }

    }

    /**

     * Print

     */

    public void print(PrintStream out, int indent) {

        out.print("local ");

        if (field != null) {

            out.print(field + "#" + field.hashCode());

            if (expr != null) {

                out.print(" = ");

                expr.print(out);

            }

        } else {

            expr.print(out);

            out.print(";");

        }

    }

}