[llvm] [X86][GlobalIsel] Reland G_ISFPCLASS (PR #165848)

[via llvm-commits]

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@@ -51,27 +50,16 @@ entry:
 }
 
 define i1 @issignaling_f(float %x) nounwind {
-; X86-LABEL: issignaling_f:
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mahesh-attarde wrote:

I chose minimal diff lines.

https://github.com/llvm/llvm-project/pull/165848