[llvm] [AMDGPU] Add regbankselect rules for G_ADD/SUB and variants (PR #159860)

[Petar Avramovic via llvm-commits]

================
@@ -72,7 +72,6 @@ body: |
     ; CHECK-NEXT: [[AND:%[0-9]+]]:sgpr(s32) = G_AND [[ICMP]], [[C]]
     ; CHECK-NEXT: [[C1:%[0-9]+]]:sgpr(s32) = G_CONSTANT i32 0
     ; CHECK-NEXT: [[SELECT:%[0-9]+]]:sgpr(s32) = G_SELECT [[AND]](s32), [[C]], [[C1]]
-    ; CHECK-NEXT: [[TRUNC:%[0-9]+]]:sgpr(s16) = G_TRUNC [[SELECT]](s32)
----------------
petar-avramovic wrote:

Need to see G_TRUNC in output, it is part of the lowering algorithm

https://github.com/llvm/llvm-project/pull/159860