[llvm] AMDGPU/GlobalISel: Add skeletons for new register bank select passes (PR #112862)

[Diana Picus via llvm-commits]

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@@ -0,0 +1,74 @@
+//===-- AMDGPURBLegalize.cpp ----------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+/// Lower G_ instructions that can't be inst-selected with register bank
+/// assignment given by RB-select based on machine uniformity info.
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rovka wrote:

Nit: Maybe mention explicitly that this is expected to run after RB-select? This might be surprising since the usual GISel pipeline has legalization first and then RB-select.

https://github.com/llvm/llvm-project/pull/112862