pipeline computation of gather_phase
pipeline computation of gather_phase

Change-Id: I0045326cffacf0355163188ca695da9c4471adc8

csail-csg/connectal,8l/connectal,chenm001/connectal,8l/connectal,csail-csg/connectal,cambridgehackers/connectal,hanw/connectal,hanw/connectal,hanw/connectal,chenm001/connectal,8l/connectal,chenm001/connectal,8l/connectal,cambridgehackers/connectal,csail-csg/connectal,hanw/connectal,csail-csg/connectal,cambridgehackers/connectal,chenm001/connectal,cambridgehackers/connectal,8l/connectal,csail-csg/connectal,chenm001/connectal,hanw/connectal,cambridgehackers/connectal