/* ____ ____ ____ ____ ______ *\
** / __// __ \/ __// __ \/ ____/ SOcos COmpiles Scala **
** __\_ \/ /_/ / /__/ /_/ /\_ \ (c) 2002, LAMP/EPFL **
** /_____/\____/\___/\____/____/ **
\* */
// $Id$
package scalac.transformer;
import scalac.*;
import scalac.util.*;
import scalac.parser.*;
import scalac.symtab.*;
import scalac.checkers.*;
import java.util.ArrayList;
public class LambdaLiftPhase extends Phase implements Kinds, Modifiers {
/** Initializes this instance. */
public LambdaLiftPhase(Global global, PhaseDescriptor descriptor) {
super(global, descriptor);
}
/** Applies this phase to the given compilation units. */
public void apply(Unit[] units) {
for (int i = 0; i < units.length; i++)
new LambdaLift(global, this).apply(units[i]);
}
public Type transformInfo(Symbol sym, Type tp) {
/*
if (global.debug)
global.log("transform info for " + sym + ":" + tp + sym.locationString());
*/
Type tp1 = tp;
if (sym != Symbol.NONE) {
switch (tp) {
case MethodType(_, _):
case PolyType(_, _):
tp1 = transform(tp, sym);
break;
default:
if (sym.kind == CLASS)
tp1 = transform(tp, sym);
else
tp1 = transform(tp, sym.owner());
}
}
if ((sym.flags & Modifiers.CAPTURED) != 0)
return global.definitions.refType(tp1);
else return tp1;
}
/** Add proxies as type arguments for propagated type parameters.
*/
Type transform(Type tp, Symbol owner) {
return transformTypeMap.setOwner(owner).apply(tp);
}
/** MapOnlyTypes => All symbols are mapped to themselves.
*/
private class TransformTypeMap extends Type.MapOnlyTypes {
Symbol owner;
// ArrayList/*<Symbol>*/ excluded = new ArrayList();
Type.Map setOwner(Symbol owner) { this.owner = owner; return this; }
public Type apply(Type tp) {
switch (tp) {
case TypeRef(Type pre, Symbol sym, Type[] targs):
if (sym.kind == CLASS) {
switch (pre) {
case ThisType(Symbol s):
if (s == Symbol.NONE) {
pre = sym.owner().enclClass().thisType();
tp = Type.TypeRef(pre, sym, targs);
}
}
}
switch (pre) {
case ThisType(_):
if (sym.kind == CLASS &&
sym.primaryConstructor().isUpdatedAt(LambdaLiftPhase.this)) {
Symbol[] tparams = sym.primaryConstructor().nextInfo().typeParams();
int i = tparams.length;
while (i > 0 && (tparams[i-1].flags & SYNTHETIC) != 0)
i--;
if (i < tparams.length) {
if (global.debug)
global.log("adding proxies for " + sym + ": " + ArrayApply.toString(tparams));
Type[] targs1 = new Type[tparams.length];
System.arraycopy(map(targs), 0, targs1, 0, targs.length);
while (i < tparams.length) {
targs1[i] = proxy(tparams[i], owner).type();
i++;
}
return Type.TypeRef(pre, sym, targs1);
}
} else if (LambdaLift.isLocal(sym, owner)) {
assert targs.length == 0;
return proxy(sym, owner).type();
}
}
break;
/*
case PolyType(Symbol[] tparams, _):
if (tparams.length != 0) {
int len = excluded.size();
for (int i = 0; i < tparams.length; i++)
excluded.add(tparams[i]);
Type tp1 = map(tp);
for (int i = 0; i < tparams.length; i++)
excluded.remove(excluded.size() - 1);
return tp1;
}
*/
}
return map(tp);
}
}
private TransformTypeMap transformTypeMap = new TransformTypeMap();
/** Return closest enclosing (type)parameter that has same name as `fv',
* or `fv' itself if this is the closest definition.
*/
Symbol proxy(Symbol fv, Symbol owner) {
if (global.debug)
global.log("proxy " + fv + " of " + fv.owner() + " in " + LambdaLift.enclFun(owner));
Symbol o = owner;
while (o.kind != NONE) {
if (global.debug)
global.log("looking in " + LambdaLift.enclFun(o) + " " +
ArrayApply.toString(o.typeParams()));
Symbol fowner = LambdaLift.enclFun(o);
if (fowner.isMethod()) {
if (LambdaLift.enclFun(fv.owner()) == fowner) return fv;
Type ft = (fowner.isUpdatedAt(this)) ? fowner.nextType()
: fowner.type();
Symbol[] ownerparams = fv.isType() ? ft.typeParams()
: ft.firstParams();
for (int i = 0; i < ownerparams.length; i++) {
if (ownerparams[i].name == fv.name)
return ownerparams[i];
}
}
assert o.owner() != o;
o = o.owner();
}
return fv;
//throw new ApplicationError("proxy " + fv + " in " + owner);
}
public Checker[] postCheckers(Global global) {
return new Checker[] {
new CheckSymbols(global),
new CheckTypes(global),
new CheckOwners(global),
new CheckNames(global)
};
}
}