IS_POW2           211 arch/xtensa/kernel/traps.c #define IS_POW2(v) (((v) & ((v) - 1)) == 0)
IS_POW2            54 drivers/staging/vc04_services/interface/vchiq_arm/vchiq_core.h #define IS_POW2(x) (x && ((x & (x - 1)) == 0))