[llvm] [DAG] Fold SETCC against isKnownNeverZero (PR #184010)

[via llvm-commits]

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@@ -418,7 +418,7 @@ define void @test8(i32 signext %arg, i32 signext %arg1) nounwind {
 ; CHECK-NEXT:    # =>This Inner Loop Header: Depth=1
 ; CHECK-NEXT:    call foo
 ; CHECK-NEXT:    ori a0, a0, -256
-; CHECK-NEXT:    bnez a0, .LBB7_1
+; CHECK-NEXT:    j .LBB7_1
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sweiglbosker wrote:

Looks like a codegen improvement to me, and the unnecessary sext.w removal that is being tested still fires so seems fine

https://github.com/llvm/llvm-project/pull/184010