[llvm] [Xtensa] Implement Code Density Option. (PR #119639)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,64 @@
+# RUN: llvm-mc -triple=xtensa -mattr=+density -disassemble < %s | FileCheck -check-prefixes=CHECK-DENSITY %s
+# RUN: llvm-mc -triple=xtensa -disassemble %s &> %t
+# RUN: FileCheck -check-prefixes=CHECK-CORE < %t %s
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MaskRay wrote:

--implicit-check-not=warning: is useful to ensure that there are no additional warnings

https://github.com/llvm/llvm-project/pull/119639