reg_bit
if (trashed_list & reg_bit(reg))
global_saved_list |= reg_bit(reg);
local_saved_list |= reg_bit(reg);
#define mark_reg_trashed(reg) trashed_list |= reg_bit((reg) & 0x1f)
#define have_global_reg(reg) (global_saved_list & reg_bit(reg))
#define have_local_reg(reg) (local_saved_list & reg_bit(reg))