[llvm] [x86] Add tan intrinsic part 4 (PR #90503)

[Farzon Lotfi via llvm-commits]

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@@ -729,12 +731,14 @@ X86TargetLowering::X86TargetLowering(const X86TargetMachine &TM,
     setOperationAction(ISD::FSIN   , MVT::f32, Expand);
     setOperationAction(ISD::FCOS   , MVT::f32, Expand);
     setOperationAction(ISD::FSINCOS, MVT::f32, Expand);
+    setOperationAction(ISD::FTAN, MVT::f32, Expand);
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farzonl wrote:

A few questions. Firs if expand is default then why do we have so many Expands in this file? For example, in this block there is a sin\cos expand. 

Outside of the two cases you called out here there are other expands added in this file for tan.  Are you saying we should only be calling `setOperationAction` if we are doing `Action` or `LibCall`?

https://github.com/llvm/llvm-project/pull/90503