GPR uses argument registers as the first group of registers to allocate. This patch uses vector argument registers, v8 to v23, as the first group to allocate. Differential Revision: https://reviews.llvm.org/D111304
Summary: Add an initial GlobalISel skeleton for RISCV. It can only run ir translator for `ret void`. Patch by Andrew Wei Reviewers: asb, sabuasal, apazos, lenary, simoncook, lewis-revill, edward-jones, rogfer01, xiangzhai, rovka, Petar.Avramovic, mgorny, dsanders Reviewed By: dsanders Subscribers: pzheng, s.egerton, dsanders, hiraditya, rbar, johnrusso, niosHD, kito-cheng, shiva0217, jrtc27, MaskRay, zzheng, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, psnobl, benna, Jim, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D65219 llvm-svn: 369467
