ID_AA64DFR0_CTX_CMPS_SHIFT
#define ID_AA64DFR0_CTX_CMPS_MASK (0xfULL << ID_AA64DFR0_CTX_CMPS_SHIFT)
((((x) >> ID_AA64DFR0_CTX_CMPS_SHIFT) & 0xf) + 1)