[clang] [CIR] Add AtomicFenceOp and signal/thread fence builtins and required helpers (PR #168346)

[Hendrik Hübner via cfe-commits]

================
@@ -5122,6 +5122,41 @@ def CIR_AtomicClearOp : CIR_Op<"atomic.clear"> {
   }];
 }
 
+def CIR_SyncScopeKind : CIR_I32EnumAttr<"SyncScopeKind", "sync scope kind", [
----------------
HendrikHuebner wrote:

Looks I accidentally overwrote the changes by force pushing without the commit. Thanks for catching this.

https://github.com/llvm/llvm-project/pull/168346