[llvm] [Xtensa] Implement Xtensa Floating Point Option. (PR #136086)

[Matt Arsenault via llvm-commits]

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@@ -175,6 +184,103 @@ XtensaTargetLowering::XtensaTargetLowering(const TargetMachine &TM,
   setOperationAction(ISD::VACOPY, MVT::Other, Custom);
   setOperationAction(ISD::VAEND, MVT::Other, Expand);
 
+  // Handle floating-point types.
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arsenm wrote:

This is mostly reinventing the default logic based on legal types 

https://github.com/llvm/llvm-project/pull/136086