/*
* 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("{}");
}
}
}