[llvm] [SelectionDAG] Remove UnsafeFPMath check in `visitFADDForFMACombine` (PR #127770)

[Matt Arsenault via llvm-commits]

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@@ -3440,6 +3485,6 @@ declare half @llvm.amdgcn.rcp.f16(half) #1
 
 attributes #0 = { nounwind "denormal-fp-math-f32"="preserve-sign,preserve-sign" }
 attributes #1 = { nounwind readnone }
-attributes #2 = { nounwind "unsafe-fp-math"="true" }
+attributes #2 = { nounwind }
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arsenm wrote:

This is evidently relying on other properties, probably should leave this for now (or find the minimum set of attributes + flags to preserve the old codegen). I see this at least was using "no-signed-zeros-fp-math"

https://github.com/llvm/llvm-project/pull/127770