Looks like a single bit in the facility bit string is being used to reflect the presence of several of the new facilities; in the past, IBM generally used one bit to indicate the presence of each new facility; bit 45 in the facility bit string says this (page 4-68):
"The distinct-operands, fast-BCR-serialization, high-word, interlocked-access, load/store-on-condition, and population-count facilities are installed in the z/Architecture architectural mode." Mike Shaw MVS/QuickRef Support Group Chicago-Soft, Ltd.
