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

[Matt Arsenault via llvm-commits]

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@@ -618,6 +618,7 @@ define <2 x i16> @v_bswap_v2i16(<2 x i16> %src) {
 ; SI-NEXT:    v_bfi_b32 v1, s4, v1, v3
 ; SI-NEXT:    v_lshrrev_b32_e32 v1, 16, v1
 ; SI-NEXT:    v_alignbit_b32 v0, v1, v0, 16
+; SI-NEXT:    v_bfe_u32 v1, v1, 0, 16
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arsenm wrote:

Regression 

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