[llvm] [SelectionDAG][RISCV] (add (vscale * C0), (vscale * C1)) to (vscale * (C0 + C1)) in getNode. (PR #144565)

[Philip Reames via llvm-commits]

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@@ -296,8 +294,9 @@ define <vscale x 16 x i8> @insert_nxv16i8_nxv1i8_2(<vscale x 16 x i8> %vec, <vsc
 ; CHECK:       # %bb.0:
 ; CHECK-NEXT:    csrr a0, vlenb
 ; CHECK-NEXT:    srli a1, a0, 3
+; CHECK-NEXT:    slli a2, a1, 1
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preames wrote:

It looks like maybe we have a missed fold here?  Or a wrap behavior difference?  

https://github.com/llvm/llvm-project/pull/144565