HFI1_S_AHG_CLEAR
qp->s_flags |= HFI1_S_AHG_CLEAR;
qp->s_flags &= ~(HFI1_S_AHG_VALID | HFI1_S_AHG_CLEAR);
if (unlikely(qp->s_flags & HFI1_S_AHG_CLEAR))