cpuid_feature_extract_signed_field
feat = cpuid_feature_extract_signed_field(mmfr0,
feat = cpuid_feature_extract_signed_field(read_sysreg(id_aa64mmfr0_el1),
if (cpuid_feature_extract_signed_field(dfr0, ID_AA64DFR0_EL1_PMUVer_SHIFT) > 0)