svm_range_new
*new = svm_range_new(svms, last + 1, old_last, false);
*new = svm_range_new(svms, old_start, start - 1, false);
new = svm_range_new(old->svms, old->start, old->last, false);
prange = svm_range_new(svms, start, l, true);
prange = svm_range_new(&p->svms, start, last, true);