Is gcc optimized for thread level parallelism?

[x z]

Is gcc optimized for thread level parallelism, in view of the recent 
development of SMT and multicore architectures?  Does gcc look for thread 
level parallelism given a single threaded program (that is, when the 
programmer does not parallelize the program using pthread etc.)?
And does gcc support any NUMA (non-uniform memory access) machines?  That 
is, does gcc
a) automatically parallelize the program for as many processors in the 
machine as possible?
b) take advantage of the non-uniform memory access (i.e. co-locate a thread 
and the data it needs on a particular processor)?