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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 ConditionalExpression extends BinaryExpression {
	Expression cond;

	/**
	* Constructor
	*/
	public ConditionalExpression(long where, Expression cond, Expression left, Expression right) {
	super(COND, where, Type.tError, left, right);
	this.cond = cond;
	}

	/**
	* Order the expression based on precedence
	*/
	public Expression order() {
	if (precedence() > cond.precedence()) {
	UnaryExpression e = (UnaryExpression)cond;
	cond = e.right;
	e.right = order();
	return e;
	}
	return this;
	}

	/**
	* Check the expression
	*/
	public Vset checkValue(Environment env, Context ctx, Vset vset, Hashtable exp) {
	ConditionVars cvars = cond.checkCondition(env, ctx, vset, exp);
	vset = left.checkValue(env, ctx, cvars.vsTrue, exp).join(
	right.checkValue(env, ctx, cvars.vsFalse, exp) );
	cond = convert(env, ctx, Type.tBoolean, cond);

	int tm = left.type.getTypeMask() \| right.type.getTypeMask();
	if ((tm & TM_ERROR) != 0) {
	type = Type.tError;
	return vset;
	}
	if (left.type.equals(right.type)) {
	type = left.type;
	} else if ((tm & TM_DOUBLE) != 0) {
	type = Type.tDouble;
	} else if ((tm & TM_FLOAT) != 0) {
	type = Type.tFloat;
	} else if ((tm & TM_LONG) != 0) {
	type = Type.tLong;
	} else if ((tm & TM_REFERENCE) != 0) {
	try {
	// This is wrong. We should be using their most common
	// ancestor, instead.
	type = env.implicitCast(right.type, left.type)
	? left.type : right.type;
	} catch (ClassNotFound e) {
	type = Type.tError;
	}
	} else if (((tm & TM_CHAR) != 0) && left.fitsType(env, ctx, Type.tChar) && right.fitsType(env, ctx, Type.tChar)) {
	type = Type.tChar;
	} else if (((tm & TM_SHORT) != 0) && left.fitsType(env, ctx, Type.tShort) && right.fitsType(env, ctx, Type.tShort)) {
	type = Type.tShort;
	} else if (((tm & TM_BYTE) != 0) && left.fitsType(env, ctx, Type.tByte) && right.fitsType(env, ctx, Type.tByte)) {
	type = Type.tByte;
	} else {
	type = Type.tInt;
	}

	left = convert(env, ctx, type, left);
	right = convert(env, ctx, type, right);
	return vset;
	}

	public Vset check(Environment env, Context ctx, Vset vset, Hashtable exp) {
	vset = cond.checkValue(env, ctx, vset, exp);
	cond = convert(env, ctx, Type.tBoolean, cond);
	return left.check(env, ctx, vset.copy(), exp).join(right.check(env, ctx, vset, exp));
	}

	/**
	* Check if constant
	*/
	public boolean isConstant() {
	return cond.isConstant() && left.isConstant() && right.isConstant();
	}

	/**
	* Simplify
	*/
	Expression simplify() {
	if (cond.equals(true)) {
	return left;
	}
	if (cond.equals(false)) {
	return right;
	}
	return this;
	}

	/**
	* Inline
	*/
	public Expression inline(Environment env, Context ctx) {
	left = left.inline(env, ctx);
	right = right.inline(env, ctx);
	if ((left == null) && (right == null)) {
	return cond.inline(env, ctx);
	}
	if (left == null) {
	left = right;
	right = null;
	cond = new NotExpression(where, cond);
	}
	cond = cond.inlineValue(env, ctx);
	return simplify();
	}

	public Expression inlineValue(Environment env, Context ctx) {
	cond = cond.inlineValue(env, ctx);
	left = left.inlineValue(env, ctx);
	right = right.inlineValue(env, ctx);
	return simplify();
	}

	/**
	* The cost of inlining this expression
	*/
	public int costInline(int thresh, Environment env, Context ctx) {
	// We need to check if right is null in case costInline()
	// is called after this expression has been inlined.
	// This call can happen, for example, in MemberDefinition#cleanup().
	// (Fix for 4069861).
	return 1 +
	cond.costInline(thresh, env, ctx) +
	left.costInline(thresh, env, ctx) +
	((right == null) ? 0 : right.costInline(thresh, env, ctx));
	}

	/**
	* Create a copy of the expression for method inlining
	*/
	public Expression copyInline(Context ctx) {
	ConditionalExpression e = (ConditionalExpression)clone();
	e.cond = cond.copyInline(ctx);
	e.left = left.copyInline(ctx);

	// If copyInline() is called after inlining is complete,
	// right could be null.
	e.right = (right == null) ? null : right.copyInline(ctx);

	return e;
	}

	/**
	* Code
	*/
	public void codeValue(Environment env, Context ctx, Assembler asm) {
	Label l1 = new Label();
	Label l2 = new Label();

	cond.codeBranch(env, ctx, asm, l1, false);
	left.codeValue(env, ctx, asm);
	asm.add(where, opc_goto, l2);
	asm.add(l1);
	right.codeValue(env, ctx, asm);
	asm.add(l2);
	}
	public void code(Environment env, Context ctx, Assembler asm) {
	Label l1 = new Label();
	cond.codeBranch(env, ctx, asm, l1, false);
	left.code(env, ctx, asm);
	if (right != null) {
	Label l2 = new Label();
	asm.add(where, opc_goto, l2);
	asm.add(l1);
	right.code(env, ctx, asm);
	asm.add(l2);
	} else {
	asm.add(l1);
	}
	}

	/**
	* Print
	*/
	public void print(PrintStream out) {
	out.print("(" + opNames[op] + " ");
	cond.print(out);
	out.print(" ");
	left.print(out);
	out.print(" ");
	if (right != null) {
	right.print(out);
	} else {
	out.print("<null>");
	}
	out.print(")");
	}
	}

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