LValueVariant.java

package zinara.ast.expression;

import zinara.ast.type.Type;
import zinara.ast.type.DictType;
import zinara.ast.type.VariantType;
import zinara.ast.type.ListType;
import zinara.ast.type.IntType;
import zinara.ast.type.FloatType;
import zinara.ast.type.BoolType;
import zinara.exceptions.KeyErrorException;
import zinara.exceptions.TypeClashException;
import zinara.exceptions.InvalidCodeException;
import zinara.code_generator.Genx86;

import java.io.IOException;

public class LValueVariant extends LValue {
    private LValue constructor;
    private String identifier;

    // requires c.getType() be of VariantType
    public LValueVariant(LValue c, String i)
	throws KeyErrorException, TypeClashException {
	// check if i is in the dictionary
	((VariantType)c.getType().getType()).getOrDie(i);

	constructor = c;
	identifier = i;
    }

    public Type getType() throws TypeClashException {
	if (type != null) return type;
	type = ((VariantType)constructor.getType().getType()).get(identifier);
	return type;
    }

    public String toString() { return constructor + "." + identifier; }

    public void tox86(Genx86 generator)
	throws IOException,InvalidCodeException{
	constructor.register = register;
	String constructorReg = generator.addrRegName(constructor.register);
	String indexValue = generator.regName(constructor.register,type);

	//Deja en constructorReg la direccion del LValue
	currentDirection(generator);

	generator.write(generator.mov(indexValue,
				      "[" + constructorReg + "]",
				      type.getType()
				      )
			);
    }

    public void currentDirection(Genx86 generator)
	throws InvalidCodeException, IOException{
	constructor.register = register;
	String constructorReg = generator.addrRegName(constructor.register);

	constructor.currentDirection(generator);
	try {
	    Integer offset = ((VariantType)constructor.getType().getType()).getOffsetFor(identifier);
	    generator.write(generator.add(constructorReg, offset.toString()));
	} catch (TypeClashException e) {}
    }

    public boolean isStaticallyKnown() {
	// for now,
	return false;
    }

    public Object staticValue() { return null; };

    public boolean isConstant() { return constructor.isConstant(); }
}