Spill cost

[Rajkishore Barik]

Hi,
Does anyone know how to obtain the overall spill cost  for the old reg 
alloc of GCC (global.c)?
I would like to know the spill cost before reload and after the reload 
(assuming reload changes the allocation).
Are there any interface already available? 
By spill cost I mean: 
for each reg i, if it is spilled, spill_cost+=REG_N_REFS(i)*REG_FREQ(i);
regards,
Raj