doubts in gimple code

[Virender Kashyap]

Hi,
     In GIMPLE IR, variables that need to live in memory are to be first 
loaded into temporaries and then used in expressions. The memory here 
referes here to data area i guess. Because for local variables which 
reside on stack , this rule does not apply, as an expression like
c = a + b ; where a,b are local variabes remain as it is in GIMPLE.
while same expression, if a, b are global variabes, becomes :
T1 = a ;
T2 = b ;
c = T1 + T2 ;
  thereby loading a, b first into temporaries and then using them in 
expressions.

  the assignments differ in global and local variables :
for a , b global :
a = b , become
  T1 = b ;
a = T1
while for a, b local
a = b , remains as
a = b

Also what exactly happens in a = b + c (b,c local) ?

-- 
Regards.
Virender