/*

 * 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

 * or visit www.oracle.com if you need additional information or have any

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 */

package sun.tools.tree;

import sun.tools.java.*;

import sun.tools.asm.Assembler;

import sun.tools.asm.Label;

import sun.tools.asm.TryData;

import sun.tools.asm.CatchData;

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 SynchronizedStatement extends Statement {

    Expression expr;

    Statement body;

    boolean needReturnSlot;   // set by inner return statement

    /**

     * Constructor

     */

    public SynchronizedStatement(long where, Expression expr, Statement body) {

        super(SYNCHRONIZED, where);

        this.expr = expr;

        this.body = body;

    }

    /**

     * Check statement

     */

    Vset check(Environment env, Context ctx, Vset vset, Hashtable exp) {

        checkLabel(env, ctx);

        CheckContext newctx = new CheckContext(ctx, this);

        vset = reach(env, vset);

        vset = expr.checkValue(env, newctx, vset, exp);

        if (expr.type.equals(Type.tNull)) {

            env.error(expr.where, "synchronized.null");

        }

        expr = convert(env, newctx, Type.tClass(idJavaLangObject), expr);

        vset = body.check(env, newctx, vset, exp);

        return ctx.removeAdditionalVars(vset.join(newctx.vsBreak));

    }

    /**

     * Inline

     */

    public Statement inline(Environment env, Context ctx) {

        if (body != null) {

            body = body.inline(env, ctx);

        }

        expr = expr.inlineValue(env, ctx);

        return this;

    }

    /**

     * Create a copy of the statement for method inlining

     */

    public Statement copyInline(Context ctx, boolean valNeeded) {

        SynchronizedStatement s = (SynchronizedStatement)clone();

        s.expr = expr.copyInline(ctx);

        if (body != null) {

            s.body = body.copyInline(ctx, valNeeded);

        }

        return s;

    }

    /**

     * Compute cost of inlining this statement

     */

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

        int cost = 1;

        if (expr != null) {

            cost += expr.costInline(thresh, env,ctx);

            if (cost >= thresh) return cost;

        }

        if (body != null) {

            cost += body.costInline(thresh, env,ctx);

        }

        return cost;

    }

    /**

     * Code

     */

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

        ClassDefinition clazz = ctx.field.getClassDefinition();

        expr.codeValue(env, ctx, asm);

        ctx = new Context(ctx);

        if (needReturnSlot) {

            Type returnType = ctx.field.getType().getReturnType();

            LocalMember localfield = new LocalMember(0, clazz, 0, returnType,

                                                   idFinallyReturnValue);

            ctx.declare(env, localfield);

            env.debugOutput("Assigning return slot to " + localfield.number);

        }

        LocalMember f1 = new LocalMember(where, clazz, 0, Type.tObject, null);

        LocalMember f2 = new LocalMember(where, clazz, 0, Type.tInt, null);

        Integer num1 = new Integer(ctx.declare(env, f1));

        Integer num2 = new Integer(ctx.declare(env, f2));

        Label endLabel = new Label();

        TryData td = new TryData();

        td.add(null);

        // lock the object

        asm.add(where, opc_astore, num1);

        asm.add(where, opc_aload, num1);

        asm.add(where, opc_monitorenter);

        // Main body

        CodeContext bodyctx = new CodeContext(ctx, this);

        asm.add(where, opc_try, td);

        if (body != null) {

            body.code(env, bodyctx, asm);

        } else {

            asm.add(where, opc_nop);

        }

        asm.add(bodyctx.breakLabel);

        asm.add(td.getEndLabel());

        // Cleanup afer body

        asm.add(where, opc_aload, num1);

        asm.add(where, opc_monitorexit);

        asm.add(where, opc_goto, endLabel);

        // Catch code

        CatchData cd = td.getCatch(0);

        asm.add(cd.getLabel());

        asm.add(where, opc_aload, num1);

        asm.add(where, opc_monitorexit);

        asm.add(where, opc_athrow);

        // Final body

        asm.add(bodyctx.contLabel);

        asm.add(where, opc_astore, num2);

        asm.add(where, opc_aload, num1);

        asm.add(where, opc_monitorexit);

        asm.add(where, opc_ret, num2);

        asm.add(endLabel);

    }

    /**

     * Print

     */

    public void print(PrintStream out, int indent) {

        super.print(out, indent);

        out.print("synchronized ");

        expr.print(out);

        out.print(" ");

        if (body != null) {

            body.print(out, indent);

        } else {

            out.print("{}");

        }

    }

}