[compiler-rt] [compiler-rt] Adds builtins support for xros. (PR #83484)

[via llvm-commits]

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@@ -162,6 +164,11 @@ if(APPLE)
       list(APPEND DARWIN_tvossim_BUILTIN_ALL_POSSIBLE_ARCHS arm64)
     endif()
   endif()
+  if(COMPILER_RT_ENABLE_XROS)
+    list(APPEND DARWIN_EMBEDDED_PLATFORMS xros)
+    set(DARWIN_xros_BUILTIN_ALL_POSSIBLE_ARCHS arm64)
+    set(DARWIN_xrossim_BUILTIN_ALL_POSSIBLE_ARCHS ${X86_64} arm64)
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rohit-rao wrote:

Per comment below, no x86_64 (I think there was in early betas). Removed.

https://github.com/llvm/llvm-project/pull/83484