[llvm] [SelectionDAG] Fold (icmp eq/ne (shift X, C), 0) -> (icmp eq/ne X, 0) (PR #88801)

[Simon Pilgrim via llvm-commits]

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@@ -586,6 +586,7 @@ define i1 @add_ultcmp_i32_i16(i32 %x) nounwind {
 ; RV64I-NEXT:    lui a1, 8
 ; RV64I-NEXT:    add a0, a0, a1
 ; RV64I-NEXT:    srliw a0, a0, 16
+; RV64I-NEXT:    slli a0, a0, 16
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RKSimon wrote:

shouldFoldConstantShiftPairToMask is enabled by default - is that affecting it?

https://github.com/llvm/llvm-project/pull/88801