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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 sun.tools.asm.SwitchData;
	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 SwitchStatement extends Statement {
	Expression expr;
	Statement args[];

	/**
	* Constructor
	*/
	public SwitchStatement(long where, Expression expr, Statement args[]) {
	super(SWITCH, where);
	this.expr = expr;
	this.args = args;
	}

	/**
	* Check statement
	*/
	Vset check(Environment env, Context ctx, Vset vset, Hashtable exp) {
	checkLabel(env, ctx);
	CheckContext newctx = new CheckContext(ctx, this);
	vset = expr.checkValue(env, newctx, reach(env, vset), exp);
	Type switchType = expr.type;

	expr = convert(env, newctx, Type.tInt, expr);

	Hashtable tab = new Hashtable();
	boolean hasDefault = false;
	// Note that vs is reset to vset.copy() on every case label.
	// If the first substatement is not a case label, it is unreached.
	Vset vs = DEAD_END;

	for (int i = 0 ; i < args.length ; i++) {
	Statement s = args[i];

	if (s.op == CASE) {

	vs = s.check(env, newctx, vs.join(vset.copy()), exp);

	Expression lbl = ((CaseStatement)s).expr;
	if (lbl != null) {
	if (lbl instanceof IntegerExpression) {
	Integer Ivalue =
	(Integer)(((IntegerExpression)lbl).getValue());
	int ivalue = Ivalue.intValue();
	if (tab.get(lbl) != null) {
	env.error(s.where, "duplicate.label", Ivalue);
	} else {
	tab.put(lbl, s);
	boolean overflow;
	switch (switchType.getTypeCode()) {
	case TC_BYTE:
	overflow = (ivalue != (byte)ivalue); break;
	case TC_SHORT:
	overflow = (ivalue != (short)ivalue); break;
	case TC_CHAR:
	overflow = (ivalue != (char)ivalue); break;
	default:
	overflow = false;
	}
	if (overflow) {
	env.error(s.where, "switch.overflow",
	Ivalue, switchType);
	}
	}
	} else {
	// Suppose a class got an error early on during
	// checking. It will set all of its members to
	// have the status "ERROR". Now suppose that a
	// case label refers to one of this class's
	// fields. When we check the case label, the
	// compiler will try to inline the FieldExpression.
	// Since the expression has ERROR status, it doesn't
	// inline. This means that instead of the case
	// label being an IntegerExpression, it will still
	// be a FieldExpression, and we will end up in this
	// else block. So, before we just assume that
	// the expression isn't constant, do a check to
	// see if it was constant but unable to inline.
	// This eliminates some spurious error messages.
	// (Bug id 4067498).
	if (!lbl.isConstant() \|\|
	lbl.getType() != Type.tInt) {
	env.error(s.where, "const.expr.required");
	}
	}
	} else {
	if (hasDefault) {
	env.error(s.where, "duplicate.default");
	}
	hasDefault = true;
	}
	} else {
	vs = s.checkBlockStatement(env, newctx, vs, exp);
	}
	}
	if (!vs.isDeadEnd()) {
	newctx.vsBreak = newctx.vsBreak.join(vs);
	}
	if (hasDefault)
	vset = newctx.vsBreak;
	return ctx.removeAdditionalVars(vset);
	}

	/**
	* Inline
	*/
	public Statement inline(Environment env, Context ctx) {
	ctx = new Context(ctx, this);
	expr = expr.inlineValue(env, ctx);
	for (int i = 0 ; i < args.length ; i++) {
	if (args[i] != null) {
	args[i] = args[i].inline(env, ctx);
	}
	}
	return this;
	}

	/**
	* Create a copy of the statement for method inlining
	*/
	public Statement copyInline(Context ctx, boolean valNeeded) {
	SwitchStatement s = (SwitchStatement)clone();
	s.expr = expr.copyInline(ctx);
	s.args = new Statement[args.length];
	for (int i = 0 ; i < args.length ; i++) {
	if (args[i] != null) {
	s.args[i] = args[i].copyInline(ctx, valNeeded);
	}
	}
	return s;
	}

	/**
	* The cost of inlining this statement
	*/
	public int costInline(int thresh, Environment env, Context ctx) {
	int cost = expr.costInline(thresh, env, ctx);
	for (int i = 0 ; (i < args.length) && (cost < thresh) ; i++) {
	if (args[i] != null) {
	cost += args[i].costInline(thresh, env, ctx);
	}
	}
	return cost;
	}

	/**
	* Code
	*/
	public void code(Environment env, Context ctx, Assembler asm) {
	CodeContext newctx = new CodeContext(ctx, this);

	expr.codeValue(env, newctx, asm);

	SwitchData sw = new SwitchData();
	boolean hasDefault = false;

	for (int i = 0 ; i < args.length ; i++) {
	Statement s = args[i];
	if ((s != null) && (s.op == CASE)) {
	Expression e = ((CaseStatement)s).expr;
	if (e != null) {
	sw.add(((IntegerExpression)e).value, new Label());
	}
	// JCOV
	else {
	hasDefault = true;
	}
	// end JCOV
	}
	}

	// JCOV
	if (env.coverage())
	sw.initTableCase();
	// end JCOV
	asm.add(where, opc_tableswitch, sw);

	for (int i = 0 ; i < args.length ; i++) {
	Statement s = args[i];
	if (s != null) {
	if (s.op == CASE) {
	Expression e = ((CaseStatement)s).expr;
	if (e != null) {
	asm.add(sw.get(((IntegerExpression)e).value));
	// JCOV
	sw.addTableCase(((IntegerExpression)e).value, s.where);
	// end JCOV
	} else {
	asm.add(sw.getDefaultLabel());
	// JCOV
	sw.addTableDefault(s.where);
	// end JCOV
	/* JCOV hasDefault = true; end JCOV */
	}
	} else {
	s.code(env, newctx, asm);
	}
	}
	}

	if (!hasDefault) {
	asm.add(sw.getDefaultLabel());
	}
	asm.add(newctx.breakLabel);
	}

	/**
	* Print
	*/
	public void print(PrintStream out, int indent) {
	super.print(out, indent);
	out.print("switch (");
	expr.print(out);
	out.print(") {\n");
	for (int i = 0 ; i < args.length ; i++) {
	if (args[i] != null) {
	printIndent(out, indent + 1);
	args[i].print(out, indent + 1);
	out.print("\n");
	}
	}
	printIndent(out, indent);
	out.print("}");
	}
	}

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