SHMEM_ARRAY_MASK
SHMEM_ARRAY_MASK(eb))
a[SHMEM_ARRAY_ENTRY(i, eb)] &= ~(SHMEM_ARRAY_MASK(eb) << \
a[SHMEM_ARRAY_ENTRY(i, eb)] |= (((val) & SHMEM_ARRAY_MASK(eb)) << \