fully adapt the gebp kernel and optimize it for CPU with only 8 registers (transplanted from 2ed88ebbf1995be90b8d0c25ff10248c8f56d023)
fully adapt the gebp kernel and optimize it for CPU with only 8 registers
(transplanted from 2ed88ebbf1995be90b8d0c25ff10248c8f56d023)

--HG--
extra : transplant_source : .%D8%8E%BB%F1%99%5B%E9%0B%8D%0C%25%FF%10%24%8C%8FV%D0%23

rotorliu/eigen,madlib/eigen_backup,mjbshaw/Eigen,rotorliu/eigen,madlib/eigen_backup,madlib/eigen_backup,rotorliu/eigen,mjbshaw/Eigen,mjbshaw/Eigen,rotorliu/eigen,mjbshaw/Eigen,madlib/eigen_backup