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	/*
	* 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
	* questions.
	*/

	package sun.tools.tree;

	import sun.tools.java.*;
	import sun.tools.asm.Assembler;
	import sun.tools.asm.Label;
	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 ReturnStatement extends Statement {
	Expression expr;

	/**
	* Constructor
	*/
	public ReturnStatement(long where, Expression expr) {
	super(RETURN, where);
	this.expr = expr;
	}

	/**
	* Check statement
	*/
	Vset check(Environment env, Context ctx, Vset vset, Hashtable exp) {
	checkLabel(env, ctx);
	vset = reach(env, vset);
	if (expr != null) {
	vset = expr.checkValue(env, ctx, vset, exp);
	}

	// Make sure the return isn't inside a static initializer
	if (ctx.field.isInitializer()) {
	env.error(where, "return.inside.static.initializer");
	return DEAD_END;
	}
	// Check return type
	if (ctx.field.getType().getReturnType().isType(TC_VOID)) {
	if (expr != null) {
	if (ctx.field.isConstructor()) {
	env.error(where, "return.with.value.constr", ctx.field);
	} else {
	env.error(where, "return.with.value", ctx.field);
	}
	expr = null;
	}
	} else {
	if (expr == null) {
	env.error(where, "return.without.value", ctx.field);
	} else {
	expr = convert(env, ctx, ctx.field.getType().getReturnType(), expr);
	}
	}
	CheckContext mctx = ctx.getReturnContext();
	if (mctx != null) {
	mctx.vsBreak = mctx.vsBreak.join(vset);
	}
	CheckContext exitctx = ctx.getTryExitContext();
	if (exitctx != null) {
	exitctx.vsTryExit = exitctx.vsTryExit.join(vset);
	}
	if (expr != null) {
	// see if we are returning a value out of a try or synchronized
	// statement. If so, find the outermost one. . . .
	Node outerFinallyNode = null;
	for (Context c = ctx; c != null; c = c.prev) {
	if (c.node == null) {
	continue;
	}
	if (c.node.op == METHOD) {
	// Don't search outside current method. Fixes 4084230.
	break;
	}
	if (c.node.op == SYNCHRONIZED) {
	outerFinallyNode = c.node;
	break;
	} else if (c.node.op == FINALLY
	&& ((CheckContext)c).vsContinue != null) {
	outerFinallyNode = c.node;
	}
	}
	if (outerFinallyNode != null) {
	if (outerFinallyNode.op == FINALLY) {
	((FinallyStatement)outerFinallyNode).needReturnSlot = true;
	} else {
	((SynchronizedStatement)outerFinallyNode).needReturnSlot = true;
	}
	}
	}
	return DEAD_END;
	}


	/**
	* Inline
	*/
	public Statement inline(Environment env, Context ctx) {
	if (expr != null) {
	expr = expr.inlineValue(env, ctx);
	}
	return this;
	}

	/**
	* The cost of inlining this statement
	*/
	public int costInline(int thresh, Environment env, Context ctx) {
	return 1 + ((expr != null) ? expr.costInline(thresh, env, ctx) : 0);
	}

	/**
	* Create a copy of the statement for method inlining
	*/
	public Statement copyInline(Context ctx, boolean valNeeded) {
	Expression e = (expr != null) ? expr.copyInline(ctx) : null;
	if ((!valNeeded) && (e != null)) {
	Statement body[] = {
	new ExpressionStatement(where, e),
	new InlineReturnStatement(where, null)
	};
	return new CompoundStatement(where, body);
	}
	return new InlineReturnStatement(where, e);
	}

	/**
	* Code
	*/
	public void code(Environment env, Context ctx, Assembler asm) {
	if (expr == null) {
	codeFinally(env, ctx, asm, null, null);
	asm.add(where, opc_return);
	} else {
	expr.codeValue(env, ctx, asm);
	codeFinally(env, ctx, asm, null, expr.type);
	asm.add(where, opc_ireturn + expr.type.getTypeCodeOffset());
	}
	}

	/**
	* Print
	*/
	public void print(PrintStream out, int indent) {
	super.print(out, indent);
	out.print("return");
	if (expr != null) {
	out.print(" ");
	expr.print(out);
	}
	out.print(";");
	}
	}

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