// events from file events/i386/arch_perfmon/events
    {0x3c, 0, 0, "CPU_CLK_UNHALTED",
     "Clock cycles when not halted"},
    {0x3c, 0, 1, "UNHALTED_REFERENCE_CYCLES",
     "Unhalted reference cycles"},
    {0xc0, 0, 0, "INST_RETIRED",
     "number of instructions retired"},
    {0x2e, 0, 0x41, "LLC_MISSES",
     "Last level cache demand requests from this core that missed the LLC"},
    {0x2e, 0, 0x4f, "LLC_REFS",
     "Last level cache demand requests from this core"},
    {0xc4, 0, 0, "BR_INST_RETIRED",
     "number of branch instructions retired"},
    {0xc5, 0, 0, "BR_MISS_PRED_RETIRED",
     "number of mispredicted branches retired (precise)"},