/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* $Id: BinOpExpr.java 468650 2006-10-28 07:03:30Z minchau $
*/
package org.apache.xalan.xsltc.compiler;
import org.apache.bcel.generic.InstructionList;
import org.apache.xalan.xsltc.compiler.util.ClassGenerator;
import org.apache.xalan.xsltc.compiler.util.ErrorMsg;
import org.apache.xalan.xsltc.compiler.util.MethodGenerator;
import org.apache.xalan.xsltc.compiler.util.MethodType;
import org.apache.xalan.xsltc.compiler.util.Type;
import org.apache.xalan.xsltc.compiler.util.TypeCheckError;
/**
* @author Jacek Ambroziak
* @author Santiago Pericas-Geertsen
*/
final class BinOpExpr extends Expression {
public static final int PLUS = 0;
public static final int MINUS = 1;
public static final int TIMES = 2;
public static final int DIV = 3;
public static final int MOD = 4;
private static final String[] Ops = {
"+", "-", "*", "/", "%"
};
private int _op;
private Expression _left, _right;
public BinOpExpr(int op, Expression left, Expression right) {
_op = op;
(_left = left).setParent(this);
(_right = right).setParent(this);
}
/**
* Returns true if this expressions contains a call to position(). This is
* needed for context changes in node steps containing multiple predicates.
*/
public boolean hasPositionCall() {
if (_left.hasPositionCall()) return true;
if (_right.hasPositionCall()) return true;
return false;
}
/**
* Returns true if this expressions contains a call to last()
*/
public boolean hasLastCall() {
return (_left.hasLastCall() || _right.hasLastCall());
}
public void setParser(Parser parser) {
super.setParser(parser);
_left.setParser(parser);
_right.setParser(parser);
}
public Type typeCheck(SymbolTable stable) throws TypeCheckError {
final Type tleft = _left.typeCheck(stable);
final Type tright = _right.typeCheck(stable);
final MethodType ptype = lookupPrimop(stable, Ops[_op],
new MethodType(Type.Void,
tleft, tright));
if (ptype != null) {
final Type arg1 = (Type) ptype.argsType().elementAt(0);
if (!arg1.identicalTo(tleft)) {
_left = new CastExpr(_left, arg1);
}
final Type arg2 = (Type) ptype.argsType().elementAt(1);
if (!arg2.identicalTo(tright)) {
_right = new CastExpr(_right, arg1);
}
return _type = ptype.resultType();
}
throw new TypeCheckError(this);
}
public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
final InstructionList il = methodGen.getInstructionList();
_left.translate(classGen, methodGen);
_right.translate(classGen, methodGen);
switch (_op) {
case PLUS:
il.append(_type.ADD());
break;
case MINUS:
il.append(_type.SUB());
break;
case TIMES:
il.append(_type.MUL());
break;
case DIV:
il.append(_type.DIV());
break;
case MOD:
il.append(_type.REM());
break;
default:
ErrorMsg msg = new ErrorMsg(ErrorMsg.ILLEGAL_BINARY_OP_ERR, this);
getParser().reportError(Constants.ERROR, msg);
}
}
public String toString() {
return Ops[_op] + '(' + _left + ", " + _right + ')';
}
}