[llvm] [DAGCombiner] Set shift flags during visit. (PR #91239)

[Matt Arsenault via llvm-commits]

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@@ -487,7 +487,8 @@ define amdgpu_kernel void @v_test_add_v2i16_inline_lo_zero_hi(ptr addrspace(1) %
 ; VI-NEXT:    s_waitcnt vmcnt(0)
 ; VI-NEXT:    v_mov_b32_e32 v0, s0
 ; VI-NEXT:    v_mov_b32_e32 v1, s1
-; VI-NEXT:    v_and_b32_e32 v3, 0xffff0000, v2
+; VI-NEXT:    v_lshrrev_b32_e32 v3, 16, v2
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arsenm wrote:

Everything here looks like a regression 

https://github.com/llvm/llvm-project/pull/91239