func checkPointsToExpectation(e *expectation, ptr pointer.Pointer, lineMapping map[string]string, prog *ssa.Program) bool {
	expected := make(map[string]int)
	surplus := make(map[string]int)
	exact := true
	for _, g := range e.args {
		if g == "..." {
			exact = false
			continue
		}
		expected[g]++
	}
	// Find the set of labels that the probe's
	// argument (x in print(x)) may point to.
	for _, label := range ptr.PointsTo().Labels() {
		name := labelString(label, lineMapping, prog)
		if expected[name] > 0 {
			expected[name]--
		} else if exact {
			surplus[name]++
		}
	}
	// Report multiset difference:
	ok := true
	for _, count := range expected {
		if count > 0 {
			ok = false
			e.errorf("value does not alias these expected labels: %s", join(expected))
			break
		}
	}
	for _, count := range surplus {
		if count > 0 {
			ok = false
			e.errorf("value may additionally alias these labels: %s", join(surplus))
			break
		}
	}
	return ok
}
func checkTypesExpectation(e *expectation, ptr pointer.Pointer, typ types.Type) bool {
	var expected typemap.M
	var surplus typemap.M
	exact := true
	for _, g := range e.types {
		if g == types.Typ[types.Invalid] {
			exact = false
			continue
		}
		expected.Set(g, struct{}{})
	}

	if !pointer.CanHaveDynamicTypes(typ) {
		e.errorf("@types expectation requires an interface- or reflect.Value-typed operand, got %s", typ)
		return false
	}

	// Find the set of types that the probe's
	// argument (x in print(x)) may contain.
	for _, T := range ptr.PointsTo().DynamicTypes().Keys() {
		if expected.At(T) != nil {
			expected.Delete(T)
		} else if exact {
			surplus.Set(T, struct{}{})
		}
	}
	// Report set difference:
	ok := true
	if expected.Len() > 0 {
		ok = false
		e.errorf("interface cannot contain these types: %s", expected.KeysString())
	}
	if surplus.Len() > 0 {
		ok = false
		e.errorf("interface may additionally contain these types: %s", surplus.KeysString())
	}
	return ok
}