typedef struct
{
 unsigned live_mask:16;
} node_header;

extern void bar(unsigned);

void foo(node_header *n)
{
    unsigned transfer_masks[4];
    unsigned i;
    unsigned mask = ((n)->live_mask);
    unsigned input_mask;
    
    if (mask)
    {
        input_mask = ((mask << 2) | (mask << 1) | (mask >> 1) | (mask >> 2)) & 7;
        transfer_masks[0] = input_mask;
        transfer_masks[1] = input_mask;
    }
    
    for(i=0; i < 4; i++)
        bar(transfer_masks[i]);
}