bitset_andnot(pos_regs, ou->co->cenv->ignore_colors);
assert(bitset_popcnt(pos_regs) != 0 && "No register is allowed for this node !!?");
bitset_andnot(pos_regs, ou->co->cenv->ignore_colors);
assert(bitset_popcnt(pos_regs) != 0 && "No register is allowed for this node !!?");