[llvm] [Xtensa] Initial codegen support from IR (PR #78548)

[Sergei Barannikov via llvm-commits]

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@@ -0,0 +1,30 @@
+//===- Xtensa.h - Top-level interface for Xtensa representation -*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
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s-barannikov wrote:

Current license header template doesn't include this string. I don't know if this is important or not.

https://github.com/llvm/llvm-project/pull/78548