[clang] Add clang atomic control options and attribute (PR #114841)

[Yaxun Liu via cfe-commits]

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@@ -1096,6 +1100,177 @@ inline void FPOptions::applyChanges(FPOptionsOverride FPO) {
   *this = FPO.applyOverrides(*this);
 }
 
+/// Atomic control options
+class AtomicOptionsOverride;
+class AtomicOptions {
+public:
+  using storage_type = uint16_t;
+
+  static constexpr unsigned StorageBitSize = 8 * sizeof(storage_type);
+
+  static constexpr storage_type FirstShift = 0, FirstWidth = 0;
+#define OPTION(NAME, STR, TYPE, WIDTH, PREVIOUS)                               \
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yxsamliu wrote:

will remove the macro-based design

https://github.com/llvm/llvm-project/pull/114841