/** Prepend given list of elements to front of list, forming and returning a new list. */
public List<A> prependList(List<A> xs) {
if (this.isEmpty()) return xs;
if (xs.isEmpty()) return this;
if (xs.tail.isEmpty()) return prepend(xs.head);
// return this.prependList(xs.tail).prepend(xs.head);
List<A> result = this;
List<A> rev = xs.reverse();
Assert.check(rev != xs);
// since xs.reverse() returned a new list, we can reuse the
// individual List objects, instead of allocating new ones.
while (rev.nonEmpty()) {
List<A> h = rev;
rev = rev.tail;
h.setTail(result);
result = h;
}
return result;
}
/**
* Count trailing zero bits in an int. Algorithm from "Hacker's Delight" by Henry S. Warren Jr.
* (figure 5-13)
*/
private static int trailingZeroBits(int x) {
Assert.check(wordlen == 32);
if (x == 0) return 32;
int n = 1;
if ((x & 0xffff) == 0) {
n += 16;
x >>>= 16;
}
if ((x & 0x00ff) == 0) {
n += 8;
x >>>= 8;
}
if ((x & 0x000f) == 0) {
n += 4;
x >>>= 4;
}
if ((x & 0x0003) == 0) {
n += 2;
x >>>= 2;
}
return n - (x & 1);
}
@Override
public Void visitTypeVar(TypeVar t, Void ignored) {
if (indexOf(t, WhereClauseKind.TYPEVAR) == -1) {
// access the bound type and skip error types
Type bound = t.bound;
while ((bound instanceof ErrorType)) bound = ((ErrorType) bound).getOriginalType();
// retrieve the bound list - if the type variable
// has not been attributed the bound is not set
List<Type> bounds =
(bound != null && bound.tsym != null) ? types.getBounds(t) : List.<Type>nil();
nameSimplifier.addUsage(t.tsym);
boolean boundErroneous =
bounds.head == null || bounds.head.tag == NONE || bounds.head.tag == ERROR;
if ((t.tsym.flags() & SYNTHETIC) == 0) {
// this is a true typevar
JCDiagnostic d =
diags.fragment(
"where.typevar" + (boundErroneous ? ".1" : ""),
t,
bounds,
Kinds.kindName(t.tsym.location()),
t.tsym.location());
whereClauses.get(WhereClauseKind.TYPEVAR).put(t, d);
symbolPreprocessor.visit(t.tsym.location(), null);
visit(bounds);
} else {
Assert.check(!boundErroneous);
// this is a fresh (synthetic) tvar
JCDiagnostic d = diags.fragment("where.fresh.typevar", t, bounds);
whereClauses.get(WhereClauseKind.TYPEVAR).put(t, d);
visit(bounds);
}
}
return null;
}
/** Include x in this set. */
public void incl(int x) {
Assert.check(x >= 0);
sizeTo((x >>> wordshift) + 1);
bits[x >>> wordshift] = bits[x >>> wordshift] | (1 << (x & wordmask));
}
/**
* Replace the specified diagnostic handler with the handler that was current at the time this
* handler was created. The given handler must be the currently installed handler; it must be
* specified explicitly for clarity and consistency checking.
*/
public void popDiagnosticHandler(DiagnosticHandler h) {
Assert.check(diagnosticHandler == h);
diagnosticHandler = h.prev;
}
public String formatPosition(JCDiagnostic d, PositionKind pk, Locale l) {
Assert.check(d.getPosition() != Position.NOPOS);
return String.valueOf(getPosition(d, pk));
}