[llvm] Allow more dead AND operations to be eliminated (PR #123686)

[Matt Arsenault via llvm-commits]

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@@ -201,9 +201,10 @@ define i16 @test_ctpop_i16(i16 %a) nounwind {
 ; LA32-NEXT:    add.w $a0, $a2, $a0
 ; LA32-NEXT:    srli.w $a1, $a0, 4
 ; LA32-NEXT:    add.w $a0, $a0, $a1
-; LA32-NEXT:    bstrpick.w $a1, $a0, 11, 8
-; LA32-NEXT:    andi $a0, $a0, 15
+; LA32-NEXT:    andi $a0, $a0, 3855
+; LA32-NEXT:    srli.w $a1, $a0, 8
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arsenm wrote:

Regression 

https://github.com/llvm/llvm-project/pull/123686