[llvm] [Xtensa] Implement Windowed Register Option. (PR #121118)

[Andrei Safronov via llvm-commits]

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@@ -18,9 +18,15 @@ include "llvm/Target/Target.td"
 // Subtarget Features.
 //===----------------------------------------------------------------------===//
 def FeatureDensity : SubtargetFeature<"density", "HasDensity", "true",
-                    "Enable Density instructions">;
+                                      "Enable Density instructions">;
 def HasDensity : Predicate<"Subtarget->hasDensity()">,
-                     AssemblerPredicate<(all_of FeatureDensity)>;
+                 AssemblerPredicate<(all_of FeatureDensity)>;
+
+def FeatureWindowed : SubtargetFeature<"windowed", "HasWindowed", "true",
+                                       "Enable Xtensa Windowed Register option">;
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andreisfr wrote:

I created special file XtensaFeatures.td for Xtensa ISA extensions/features.

https://github.com/llvm/llvm-project/pull/121118