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

[Fangrui Song via llvm-commits]

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@@ -111,6 +114,17 @@ bool Xtensa::checkRegister(MCRegister RegNo, const FeatureBitset &FeatureBits) {
   return true;
 }
 
+// Get Xtensa User Register by encoding value.
+MCRegister Xtensa::getUserRegister(unsigned Code) {
+  switch (Code) {
+  case 232:
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MaskRay wrote:

Where does the magic value come from?

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