Segmented stack

[Shucai via Digitalmars-d]

I am doing research on segmented stack mechanisms, and in 
addition to academic papers, I am surveying whether segmented 
stack mechanism is still useful on 64-bit machines. On 64 bit 
machines, why  they don’t just use a big enough stack, for 
example, 1GB or even larger?  Are segmented stacks only useful 
for 32 bit machines?  Are there other reasons for segmented 
stacks on 64 bit machines?

Any response is appreciated, thanks, Shucai