[llvm] [DAGCombiner] Remove NoSignedZerosFPMath in visitFNEG (PR #162052)

[Matt Arsenault via llvm-commits]

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@@ -5048,6 +5132,8 @@ declare <2 x half> @llvm.fmuladd.v2f16(<2 x half>, <2 x half>, <2 x half>) #0
 
 attributes #0 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }
 ;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
+; CI-NSZ: {{.*}}
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arsenm wrote:

Should this remove the flag from the run lines and merge them? 

https://github.com/llvm/llvm-project/pull/162052