/*
* Returns the least specific supertype of t that maintains the properties
* required by tc.
*/
Type relaxType(Type t, TypeConstraint tc) {
always_assert(t <= Type::Gen && t != Type::Bottom);
if (tc.category == DataTypeGeneric) return Type::Gen;
auto outerRelaxed = relaxOuter(t & Type::Cell, tc);
if (t.notBoxed()) return outerRelaxed;
auto innerType = (t & Type::BoxedCell).innerType();
auto innerRelaxed = tc.innerCat == DataTypeGeneric ? Type::Cell
: relaxOuter(innerType,
tc.inner());
// Only add outerRelax into the result type if t had a meaningful outer type
// coming in.
return (t.isBoxed() ? Type::Bottom : outerRelaxed) |
(innerRelaxed - Type::Uninit).box();
}
/*
* Returns true iff t is not boxed, or if tc.innerCat is satisfied by t's inner
* type.
*/
static bool typeFitsInnerConstraint(Type t, TypeConstraint tc) {
return tc.innerCat == DataTypeGeneric || t.notBoxed() ||
typeFitsOuterConstraint((t & Type::BoxedCell).innerType(), tc.inner());
}