4d96a6b7be
According to the N2 Software Optimization Guide, arithmetic ops with LSL ≤ 4, no flagset logical ops, and flagset logical ops with LSL = 0 have a latency of 1 and use pipeline group I. However, most of these ops were being modelled as having a latency of 2 and using pipeline M. The affected instructions include the "unshifted" versions of ADD/SUB, among others. Differential Revision: https://reviews.llvm.org/D145370