[clang] [clang] Add support for cluster sync scope (PR #162575)

[Shilei Tian via cfe-commits]

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@@ -223,14 +237,17 @@ class AtomicScopeHIPModel : public AtomicScopeModel {
 /// Defines the generic atomic scope model.
 class AtomicScopeGenericModel : public AtomicScopeModel {
 public:
-  /// The enum values match predefined built-in macros __ATOMIC_SCOPE_*.
+  /// The enum values match predefined built-in macros __MEMORY_SCOPE_*.
   enum ID {
     System = 0,
     Device = 1,
     Workgroup = 2,
     Wavefront = 3,
     Single = 4,
-    Last = Single
+    Cluster = 5,
+    End,
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shiltian wrote:

I'd remove it if it is not necessary.

https://github.com/llvm/llvm-project/pull/162575